NZ792149A - Headgear for a patient interface - Google Patents

Abstract

The present inventions seeks to address problems of the prior art relating to comfort, cost, efficacy, ease of use and manufacturability. A positioning and stabilising structure comprising at least one gas delivery tube to receive the flow of air from a connection port on top of the patient's head and to deliver the flow of air to the entrance of the patient's airways via the seal-forming structure, the at least one gas delivery tube comprising a tube wall having an extendable concertina structure comprising a plurality of folds in the tube wall alternatingly forming a plurality of ridges and a plurality of grooves, the folds able to be at least partially unfolded to increase a separation of the ridges to elongate the extendable concertina structure; and one or more ridge connecting portions provided to the tube wall, each of the one or more ridge connecting portions connecting two or more adjacent ridges of the plurality of ridges and being configured to resist the separation of the ridges. nd to deliver the flow of air to the entrance of the patient's airways via the seal-forming structure, the at least one gas delivery tube comprising a tube wall having an extendable concertina structure comprising a plurality of folds in the tube wall alternatingly forming a plurality of ridges and a plurality of grooves, the folds able to be at least partially unfolded to increase a separation of the ridges to elongate the extendable concertina structure; and one or more ridge connecting portions provided to the tube wall, each of the one or more ridge connecting portions connecting two or more adjacent ridges of the plurality of ridges and being configured to resist the separation of the ridges.

Description

The present inventions seeks to address problems of the prior art relating to comfort, cost, efficacy, ease of use and manufacturability. A positioning and stabilising structure comprising at least one gas delivery tube to receive the flow of air from a connection port on top of the patient's head and to deliver the flow of air to the entrance of the patient's s via the rming structure, the at least one gas delivery tube comprising a tube wall having an extendable concertina structure comprising a plurality of folds in the tube wall alternatingly forming a plurality of ridges and a plurality of grooves, the folds able to be at least partially unfolded to increase a separation of the ridges to elongate the extendable concertina ure; and one or more ridge connecting portions provided to the tube wall, each of the one or more ridge connecting portions connecting two or more adjacent ridges of the plurality of ridges and being configured to resist the separation of the ridges.

NZ 792149 P1415NZ7 / 506176NZDIV6 HEADGEAR FOR A PATIENT INTERFACE 1 CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. ional Application No. 62/764,995, filed August 20, 2018, the entire contents of which is incorporated herein by reference.

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it s in Patent Office patent files or records, but otherwise es all copyright rights whatsoever. 2 BACKGROUND OF THE TECHNOLOGY 2.1 FIELD OF THE LOGY The present logy relates to one or more of the screening, diagnosis, monitoring, treatment, prevention and amelioration of respiratory-related ers.

The present technology also relates to medical devices or apparatus, and their use. 2.2 DESCRIPTION OF THE RELATED ART 2.2.1 Human Respiratory System and its Disorders The respiratory system of the body facilitates gas exchange. The nose and mouth form the entrance to the airways of a patient.

The airways include a series of branching tubes, which become narrower, shorter and more numerous as they penetrate deeper into the lung. The prime function of the lung is gas exchange, allowing oxygen to move from the inhaled air into the venous blood and carbon e to move in the opposite direction. The trachea divides into right and left main bronchi, which r divide eventually into terminal bronchioles. The bronchi make up the ting airways, and do not take part in gas exchange. Further divisions of the airways lead to the respiratory bronchioles, and eventually to the alveoli. The alveolated region of the lung is where the gas exchange P1415NZ7 / 506176NZDIV6 takes place, and is referred to as the respiratory zone. See “Respiratory Physiology”, by John B. West, Lippincott Williams & Wilkins, 9th edition published 2012.

A range of respiratory disorders exist. Certain disorders may be characterised by particular events, e.g. apneas, hypopneas, and hyperpneas.

Examples of respiratory disorders e Obstructive Sleep Apnea (OSA), Cheyne-Stokes Respiration (CSR), atory insufficiency, Obesity Hyperventilation Syndrome (OHS), c Obstructive Pulmonary Disease (COPD), Neuromuscular e (NMD) and Chest wall disorders.

Obstructive Sleep Apnea (OSA), a form of Sleep Disordered Breathing (SDB), is characterised by events including occlusion or obstruction of the upper air passage during sleep. It results from a combination of an abnormally small upper airway and the normal loss of muscle tone in the region of the , soft palate and posterior oropharyngeal wall during sleep. The condition causes the affected patient to stop breathing for periods typically of 30 to 120 s in duration, sometimes 200 to 300 times per night. It often causes excessive daytime somnolence, and it may cause cardiovascular disease and brain damage. The syndrome is a common disorder, particularly in middle aged overweight males, although a person affected may have no awareness of the problem. See US Patent No. 4,944,310 (Sullivan).

Cheyne-Stokes Respiration (CSR) is another form of sleep disordered breathing. CSR is a er of a patient's respiratory controller in which there are rhythmic alternating s of waxing and waning ventilation known as CSR cycles.

CSR is characterised by repetitive de-oxygenation and re-oxygenation of the arterial blood. It is possible that CSR is l because of the repetitive hypoxia. In some ts CSR is associated with repetitive arousal from sleep, which causes severe sleep disruption, sed sympathetic activity, and increased afterload. See US Patent No. 6,532,959 (Berthon-Jones).

Respiratory failure is an umbrella term for atory disorders in which the lungs are unable to inspire sufficient oxygen or exhale sufficient CO2 to meet the patient’s needs. Respiratory failure may encompass some or all of the following disorders.

Z7 / 506176NZDIV6 A patient with respiratory insufficiency (a form of respiratory failure) may experience abnormal shortness of breath on exercise.

Obesity Hyperventilation Syndrome (OHS) is defined as the combination of severe obesity and awake chronic apnia, in the absence of other known causes for hypoventilation. Symptoms include a, morning headache and excessive daytime sleepiness.

Chronic Obstructive Pulmonary Disease (COPD) encompasses any of a group of lower airway diseases that have certain characteristics in common. These include increased resistance to air movement, ed expiratory phase of ation, and loss of the normal elasticity of the lung. Examples of COPD are emphysema and chronic bronchitis. COPD is caused by chronic tobacco smoking ry risk factor), occupational exposures, air pollution and genetic factors.

Symptoms include: dyspnea on exertion, chronic cough and sputum production. uscular Disease (NMD) is a broad term that asses many diseases and ailments that impair the oning of the muscles either directly via intrinsic muscle pathology, or indirectly via nerve pathology. Some NMD patients are terised by progressive muscular impairment leading to loss of ambulation, being wheelchair-bound, swallowing difficulties, respiratory muscle weakness and, eventually, death from respiratory failure. Neuromuscular disorders can be divided into rapidly progressive and slowly progressive: (i) Rapidly progressive ers: Characterised by muscle impairment that worsens over months and results in death within a few years (e.g. Amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy (DMD) in teenagers); (ii) le or slowly ssive disorders: terised by muscle impairment that worsens over years and only mildly reduces life expectancy (e.g. Limb girdle, Facioscapulohumeral and Myotonic muscular dystrophy). Symptoms of respiratory failure in NMD include: increasing generalised weakness, dysphagia, dyspnea on exertion and at rest, fatigue, sleepiness, morning headache, and difficulties with concentration and mood changes.

Chest wall disorders are a group of ic deformities that result in inefficient coupling between the respiratory muscles and the thoracic cage. The disorders are usually characterised by a restrictive defect and share the potential of P1415NZ7 / 506176NZDIV6 long term hypercapnic respiratory failure. Scoliosis and/or kyphoscoliosis may cause severe respiratory e. ms of respiratory failure include: dyspnea on exertion, peripheral oedema, orthopnea, repeated chest infections, morning headaches, fatigue, poor sleep y and loss of appetite.

A range of therapies have been used to treat or ameliorate such conditions.

Furthermore, otherwise healthy individuals may take advantage of such therapies to prevent atory disorders from arising. However, these have a number of shortcomings. 2.2.2 Therapy Various ies, such as Continuous Positive Airway Pressure (CPAP) therapy, Non-invasive ventilation (NIV) and ve ventilation (IV) have been used to treat one or more of the above respiratory disorders.

Continuous Positive Airway Pressure (CPAP) therapy has been used to treat Obstructive Sleep Apnea (OSA). The mechanism of action is that continuous positive airway pressure acts as a pneumatic splint and may prevent upper airway occlusion, such as by pushing the soft palate and tongue forward and away from the posterior ryngeal wall. Treatment of OSA by CPAP therapy may be voluntary, and hence patients may elect not to comply with y if they find devices used to provide such therapy one or more of: uncomfortable, difficult to use, ive and aesthetically unappealing.

Non-invasive ventilation (NIV) provides ventilatory support to a patient h the upper airways to assist the patient breathing and/or maintain adequate oxygen levels in the body by doing some or all of the work of breathing. The ventilatory support is provided via a non-invasive patient interface. NIV has been used to treat CSR and respiratory failure, in forms such as OHS, COPD, NMD and Chest Wall disorders. In some forms, the comfort and effectiveness of these therapies may be improved.

Invasive ventilation (IV) provides ventilatory support to patients that are no longer able to effectively breathe themselves and may be provided using a P1415NZ7 / 506176NZDIV6 tracheostomy tube. In some forms, the comfort and effectiveness of these ies may be improved. 2.2.3 Treatment Systems These therapies may be provided by a treatment system or device. Such systems and devices may also be used to screen, diagnose, or monitor a condition without treating it.

A ent system may comprise a Respiratory Pressure Therapy Device (RPT device), an air circuit, a humidifier, a patient interface, and data management.

Another form of treatment system is a mandibular repositioning device. 2.2.3.1 Patient Interface A patient ace may be used to interface atory equipment to its , for e by providing a flow of air to an entrance to the airways. The flow of air may be provided via a mask to the nose and/or mouth, a tube to the mouth or a tracheostomy tube to the trachea of a patient. Depending upon the therapy to be applied, the patient interface may form a seal, e.g., with a region of the patient's face, to facilitate the delivery of gas at a pressure at sufficient ce with ambient pressure to effect therapy, e.g., at a positive pressure of about 10 cmH2O relative to ambient pressure. For other forms of therapy, such as the delivery of oxygen, the patient interface may not include a seal sufficient to facilitate delivery to the airways of a supply of gas at a positive pressure of about 10 cmH2O.

Certain other mask s may be functionally unsuitable for the present field. For example, purely ornamental masks may be unable to maintain a suitable pressure. Mask systems used for underwater swimming or diving may be configured to guard t ingress of water from an external higher pressure, but not to maintain air internally at a higher pressure than ambient.

Certain masks may be clinically urable for the present technology e.g. if they block airflow via the nose and only allow it via the mouth.

P1415NZ7 / 506176NZDIV6 Certain masks may be uncomfortable or tical for the present technology if they e a patient to insert a portion of a mask structure in their mouth to create and maintain a seal via their lips.

Certain masks may be impractical for use while sleeping, e.g. for sleeping while lying on one’s side in bed with a head on a pillow.

The design of a t interface ts a number of nges. The face has a complex three-dimensional shape. The size and shape of noses and heads varies considerably between individuals. Since the head includes bone, cartilage and soft tissue, different regions of the face respond differently to ical . The jaw or mandible may move relative to other bones of the skull. The whole head may move during the course of a period of respiratory therapy.

As a consequence of these challenges, some masks suffer from being one or more of obtrusive, aesthetically undesirable, costly, poorly fitting, ult to use, and uncomfortable especially when worn for long periods of time or when a patient is unfamiliar with a system. Wrongly sized masks can give rise to reduced compliance, reduced comfort and poorer patient outcomes. Masks designed solely for aviators, masks designed as part of personal protection equipment (e.g. filter masks), SCUBA masks, or for the administration of anaesthetics may be tolerable for their original application, but nevertheless such masks may be undesirably uncomfortable to be worn for extended periods of time, e.g., several hours. This fort may lead to a reduction in patient compliance with therapy. This is even more so if the mask is to be worn during sleep.

CPAP therapy is highly ive to treat certain respiratory disorders, provided patients comply with therapy. If a mask is uncomfortable, or difficult to use a patient may not comply with therapy. Since it is often recommended that a patient regularly wash their mask, if a mask is difficult to clean (e.g., difficult to assemble or disassemble), patients may not clean their mask and this may impact on patient compliance.

While a mask for other ations (e.g. aviators) may not be suitable for use in treating sleep disordered breathing, a mask designed for use in treating sleep disordered breathing may be suitable for other applications.

Z7 / 506176NZDIV6 For these reasons, t aces for delivery of CPAP during sleep form a distinct field. 2.2.3.1.1 Seal-forming structure Patient interfaces may include a seal-forming structure. Since it is in direct contact with the patient’s face, the shape and configuration of the orming structure can have a direct impact the effectiveness and comfort of the patient A patient interface may be partly characterised according to the design intent of where the seal-forming structure is to engage with the face in use. In one form of patient interface, a seal-forming structure may comprise a first sub-portion to form a seal around the left naris and a second rtion to form a seal around the right naris. In one form of patient interface, a seal-forming structure may comprise a single element that nds both nares in use. Such single element may be designed to for example overlay an upper lip region and a nasal bridge region of a face. In one form of patient interface a seal-forming structure may comprise an element that surrounds a mouth region in use, e.g. by g a seal on a lower lip region of a face.

In one form of patient interface, a seal-forming structure may comprise a single element that surrounds both nares and a mouth region in use. These different types of patient interfaces may be known by a variety of names by their manufacturer including nasal masks, full-face masks, nasal pillows, nasal puffs and oro-nasal masks.

A seal-forming structure that may be effective in one region of a patient’s face may be inappropriate in another region, e.g. because of the different shape, structure, variability and sensitivity regions of the patient’s face. For example, a seal on swimming goggles that overlays a t’s forehead may not be appropriate to use on a patient’s nose.

Certain seal-forming structures may be designed for mass manufacture such that one design fits and is comfortable and effective for a wide range of different face shapes and sizes. To the extent to which there is a mismatch between the shape of the patient’s face, and the seal-forming ure of the mass-manufactured patient interface, one or both must adapt in order for a seal to form.

P1415NZ7 / 506176NZDIV6 One type of seal-forming structure extends around the periphery of the patient interface, and is intended to seal against the patient's face when force is applied to the patient interface with the seal-forming structure in nting engagement with the patient's face. The seal-forming structure may e an air or fluid filled cushion, or a moulded or formed surface of a resilient seal element made of an mer such as a rubber. With this type of seal-forming structure, if the fit is not adequate, there will be gaps between the seal-forming structure and the face, and additional force will be required to force the patient interface against the face in order to achieve a seal.

Another type of seal-forming structure incorporates a flap seal of thin material positioned about the ery of the mask so as to provide a self-sealing action against the face of the patient when positive pressure is applied within the mask. Like the previous style of seal forming portion, if the match between the face and the mask is not good, additional force may be required to achieve a seal, or the mask may leak. Furthermore, if the shape of the seal-forming structure does not match that of the patient, it may crease or buckle in use, giving rise to leaks.

Another type of orming structure may comprise a on-fit element, e.g. for insertion into a naris, however some patients find these uncomfortable.

Another form of seal-forming structure may use adhesive to e a seal. Some patients may find it inconvenient to constantly apply and remove an adhesive to their face.

A range of patient interface seal-forming structure technologies are sed in the ing patent ations, assigned to ResMed d: WO 1998/004310; One form of nasal pillow is found in the Adam Circuit manufactured by Puritan Bennett. Another nasal pillow, or nasal puff is the subject of US Patent 4,782,832 (Trimble et al.), assigned to Puritan-Bennett Corporation.

ResMed Limited has manufactured the following products that incorporate nasal pillows: SWIFTTM nasal pillows mask, M II nasal pillows P1415NZ7 / 506176NZDIV6 mask, SWIFTTM LT nasal pillows mask, SWIFTTM FX nasal pillows mask and MIRAGE LIBERTYTM full-face mask. The following patent applications, assigned to ResMed Limited, describe examples of nasal pillows masks: International Patent Application WO2004/073778 ibing amongst other things aspects of the ResMed Limited SWIFTTM nasal pillows), US Patent Application 2009/0044808 (describing amongst other things aspects of the ResMed Limited SWIFTTM LT nasal pillows); International Patent Applications amongst other things aspects of the ResMed Limited MIRAGE LIBERTYTM ace mask); International Patent Application things aspects of the ResMed Limited SWIFTTM FX nasal pillows). 2.2.3.1.2 Positioning and stabilising A seal-forming structure of a patient interface used for positive air re therapy is subject to the ponding force of the air pressure to disrupt a seal. Thus a variety of techniques have been used to position the seal-forming structure, and to maintain it in sealing relation with the appropriate n of the face.

One technique is the use of adhesives. See for example US Patent Application Publication No. US 2010/0000534. However, the use of adhesives may be uncomfortable for some.

Another technique is the use of one or more straps and/or stabilising harnesses. Many such harnesses suffer from being one or more of tting, bulky, uncomfortable and awkward to use. 2.2.3.1.3 Pressurised Air Conduit In one type of treatment system, a flow of pressurised air is provided to a patient interface through a conduit in an air circuit that fluidly connects to the patient interface so that, when the patient interface is positioned on the patient’s face during use, the conduit extends out of the t interface ds away from the t’s face. This may mes be referred to as an “elephant trunk” style of ace.

Some patients find such interfaces to be unsightly and are consequently deterred from wearing them, reducing patient compliance. onally, conduits P1415NZ7 / 506176NZDIV6 connecting to an interface at the front of a patient’s face may sometimes be vulnerable to becoming tangled up in bed clothes. 1.4 Pressurised Air Conduit used for Positioning / Stabilising the Seal- Forming Structure An alternative type of treatment system which seeks to address these ms comprises a patient ace in which a tube that delivers pressurised air to the patient’s airways also functions as part of the headgear to position and ise the seal-forming portion of the patient interface to the appropriate part of the patient’s face. This type of patient interface may be referred to as incorporating ‘headgear tubing’ or ‘conduit headgear’. Such patient interfaces allow the conduit in the air circuit providing the flow of rised air from a respiratory pressure therapy device to t to the patient ace in a position other than in front of the patient’s face.

One example of such a treatment system is disclosed in US Patent Publication No. 2007/0246043, the contents of which are incorporated herein by reference, in which the conduit connects to a tube in the t interface through a port positioned in use on top of the t’s head.

The Philips DreamWear™ mask includes such headgear tubing. The length of the DreamWear™ headgear tubes cannot be adjusted. Consequently, the DreamWear™ headgear is ed in three different sizes to cater for different sized patient faces. Providing a greater number of different sizes may increase the complexity and cost to manufacture the headgear and may result in larger packaging.

Additionally, a supply of discretely sized masks may limit the extent to which differently sized patient heads can be accommodated. There may be a greater chance of some patients being unable to achieve what they consider a “perfect” fit if forced to choose between discrete sizes that are not adjustable in length.

Patient interfaces incorporating ar tubing may e some advantages, for example avoiding a conduit connecting to the patient interface at the front of a patient’s face, which may be unsightly and obtrusive. r, it is desirable for patient aces incorporating headgear tubing to be comfortable for a patient to wear over a prolonged duration when the patient is asleep while forming an effective seal with the patient’s face.

P1415NZ7 / 506176NZDIV6 2.2.3.2 Respiratory Pressure Therapy (RPT) Device A respiratory re therapy (RPT) device may be used individually or as part of a system to deliver one or more of a number of therapies described above, such as by operating the device to generate a flow of air for delivery to an interface to the airways. The flow of air may be pressurised. Examples of RPT devices include a CPAP device and a ventilator.

Air pressure generators are known in a range of applications, e.g. industrial-scale ventilation systems. However, air pressure generators for medical applications have particular requirements not fulfilled by more generalised air pressure generators, such as the reliability, size and weight requirements of medical s. In addition, even s designed for medical treatment may suffer from shortcomings, pertaining to one or more of: comfort, noise, ease of use, efficacy, size, weight, manufacturability, cost, and reliability.

An example of the special requirements of certain RPT devices is acoustic noise.

The designer of a device may be presented with an infinite number of choices to make. Design ia often conflict, meaning that certain design choices are far from routine or inevitable. Furthermore, the t and efficacy of certain aspects may be highly sensitive to small, subtle changes in one or more parameters. 3 Humidifier Delivery of a flow of air without humidification may cause drying of s. The use of a humidifier with an RPT device and the t interface produces humidified gas that minimizes drying of the nasal mucosa and increases patient airway comfort. In on, in cooler climates, warm air applied generally to the face area in and about the patient interface is more comfortable than cold air.

A range of artificial humidification devices and systems are known, however they may not fulfil the specialised requirements of a medical fier.

Medical humidifiers are used to increase humidity and/or temperature of the flow of air in relation to ambient air when ed, typically where the t may be asleep or resting (e.g. at a hospital). A medical humidifier for bedside P1415NZ7 / 506176NZDIV6 ent may be small. A medical humidifier may be configured to only fy and/or heat the flow of air delivered to the patient without humidifying and/or heating the patient’s surroundings. Room-based systems (e.g. a sauna, an air conditioner, or an evaporative cooler), for example, may also humidify air that is breathed in by the patient, however those systems would also humidify and/or heat the entire room, which may cause discomfort to the nts. Furthermore medical humidifiers may have more stringent safety constraints than industrial humidifiers While a number of medical humidifiers are known, they can suffer from one or more shortcomings. Some l humidifiers may provide inadequate humidification, some are difficult or inconvenient to use by patients. 2.2.3.4 Data Management There may be clinical reasons to obtain data to determine whether the patient prescribed with respiratory therapy has been iant”, e.g. that the patient has used their RPT device according to one or more “compliance rules”. One example of a ance rule for CPAP therapy is that a patient, in order to be deemed compliant, is required to use the RPT device for at least four hours a night for at least 21 of 30 consecutive days. In order to determine a t's compliance, a provider of the RPT , such as a health care provider, may manually obtain data describing the patient's therapy using the RPT device, calculate the usage over a ermined time , and compare with the compliance rule. Once the health care provider has determined that the patient has used their RPT device according to the compliance rule, the health care provider may notify a third party that the patient is compliant.

There may be other aspects of a patient’s therapy that would benefit from communication of therapy data to a third party or external system.

Existing processes to communicate and manage such data can be one or more of costly, time-consuming, and error-prone. 2.2.3.5 Mandibular repositioning A mandibular repositioning device (MRD) or mandibular advancement device (MAD) is one of the treatment options for sleep apnea and snoring. It is an able oral appliance available from a dentist or other supplier that holds the P1415NZ7 / 506176NZDIV6 lower jaw (mandible) in a forward position during sleep. The MRD is a removable device that a t inserts into their mouth prior to going to sleep and removes following sleep. Thus, the MRD is not designed to be worn all of the time. The MRD may be custom made or produced in a standard form and includes a bite impression portion designed to allow fitting to a patient’s teeth. This mechanical protrusion of the lower jaw expands the space behind the tongue, puts tension on the pharyngeal walls to reduce collapse of the airway and diminishes palate vibration.

In certain examples a mandibular advancement device may comprise an upper splint that is intended to engage with or fit over teeth on the upper jaw or maxilla and a lower splint that is ed to engage with or fit over teeth on the upper jaw or mandible. The upper and lower s are connected together laterally via a pair of connecting rods. The pair of ting rods are fixed rically on the upper splint and on the lower splint.

In such a design the length of the connecting rods is selected such that when the MRD is placed in a patient’s mouth the mandible is held in an ed position. The length of the connecting rods may be ed to change the level of protrusion of the mandible. A dentist may determine a level of protrusion for the mandible that will determine the length of the connecting rods.

Some MRDs are ured to push the mandible forward relative to the maxilla while other MRDs, such as the ResMed Narval CC™ MRD are designed to retain the mandible in a forward position. This device also reduces or minimises dental and temporo-mandibular joint (TMJ) side effects. Thus, it is configured to minimises or prevent any movement of one or more of the teeth. 2.2.3.6 Vent logies Some forms of treatment systems may include a vent to allow the washout of exhaled carbon dioxide. The vent may allow a flow of gas from an interior space of a patient interface, e.g., the plenum chamber, to an exterior of the patient interface, e.g., to ambient.

The vent may comprise an orifice and gas may flow through the orifice in use of the mask. Many such vents are noisy. Others may become blocked in use and P1415NZ7 / 506176NZDIV6 thus provide insufficient washout. Some vents may be disruptive of the sleep of a bed partner 1100 of the patient 1000, e.g. through noise or focussed w.

ResMed Limited has developed a number of improved mask vent logies. See International Patent Application Publication No.

International Patent Application Publication No. 6,581,594; US Patent Application Publication No. US 2009/0050156; US Patent Application Publication No. 2009/0044808.

Table of noise of prior masks (ISO 17510-2:2007, 10 cmH2O pressure at Mask name Mask type hted A-weighted Year (approx.) sound power sound pressure level dB(A) dB(A) (uncertainty) (uncertainty) Glue-on (*) nasal 50.9 42.9 1981 ResCare nasal 31.5 23.5 1993 rd (*) ResMed nasal 29.5 21.5 1998 MirageTM (*) ResMed nasal 36 (3) 28 (3) 2000 UltraMirageTM ResMed nasal 32 (3) 24 (3) 2002 Mirage ActivaTM ResMed nasal 30 (3) 22 (3) 2008 Mirage MicroTM ResMed nasal 29 (3) 22 (3) 2008 MirageTM SoftGel ResMed nasal 26 (3) 18 (3) 2010 TM FX ResMed nasal pillows 37 29 2004 Mirage SwiftTM ResMed nasal pillows 28 (3) 20 (3) 2005 Mirage SwiftTM P1415NZ7 / 506176NZDIV6 ResMed nasal pillows 25 (3) 17 (3) 2008 Mirage SwiftTM ResMed AirFit nasal pillows 21 (3) 13 (3) 2014 (* one specimen only, measured using test method specified in ISO 3744 in CPAP mode at 10 cmH2O) Sound pressure values of a variety of objects are listed below Object A-weighted sound pressure dB(A) Notes Vacuum cleaner: Nilfisk 68 ISO 3744 at 1m Walter Broadly Litter Hog: B+ distance Grade sational speech 60 1m distance e home 50 Quiet library 40 Quiet bedroom at night 30 Background in TV studio 20 2.2.4 ing, Diagnosis, and Monitoring Systems Polysomnography (PSG) is a conventional system for sis and monitoring of cardio-pulmonary disorders, and typically involves expert clinical staff to apply the system. PSG typically involves the placement of 15 to 20 contact sensors on a patient in order to record various bodily signals such as electroencephalography (EEG), electrocardiography (ECG), electrooculograpy (EOG), omyography (EMG), etc. PSG for sleep disordered breathing has involved two nights of observation of a t in a clinic, one night of pure diagnosis and a second night of titration of treatment parameters by a clinician. PSG is therefore ive and inconvenient. In particular it is unsuitable for home screening / diagnosis / monitoring of sleep disordered breathing.

Screening and sis generally describe the identification of a condition from its signs and symptoms. Screening typically gives a true / false result indicating whether or not a patient’s SDB is severe enough to warrant further P1415NZ7 / 506176NZDIV6 investigation, while diagnosis may result in clinically actionable ation.

Screening and diagnosis tend to be one-off processes, whereas monitoring the progress of a condition can ue indefinitely. Some screening / diagnosis systems are suitable only for screening / sis, whereas some may also be used for monitoring.

Clinical experts may be able to screen, se, or monitor patients adequately based on visual ation of PSG signals. However, there are circumstances where a clinical expert may not be available, or a clinical expert may not be affordable. Different clinical experts may disagree on a patient’s condition. In addition, a given clinical expert may apply a different standard at different times. 3 BRIEF SUMMARY OF THE TECHNOLOGY The present technology is directed towards providing medical devices used in the screening, diagnosis, monitoring, amelioration, treatment, or prevention of respiratory disorders having one or more of improved comfort, cost, cy, ease of use and manufacturability.

A first aspect of the present technology relates to tus used in the screening, diagnosis, monitoring, amelioration, treatment or prevention of a atory disorder.

Another aspect of the present technology s to methods used in the screening, sis, monitoring, amelioration, treatment or tion of a respiratory disorder.

An aspect of certain forms of the present technology is to provide methods and/or apparatus that improve the compliance of patients with respiratory therapy.

One aspect of the present technology comprises a patient interface for delivery of a supply of pressurised breathable gas to an entrance of a patient’s airways.

Another aspect of the present technology is directed to a patient ace that may comprise: a plenum chamber; a seal-forming structure; and a oning and stabilising structure. The patient interface may further comprise a vent structure. The P1415NZ7 / 506176NZDIV6 patient may further be configured to leave the patient’s mouth uncovered, or if the orming structure is configured to seal around the patient’s nose and mouth, the patient interface may be further configured to allow the patient to breath from t in the absence of a flow of pressurised air through the plenum chamber inlet port.

Another aspect of the present technology is ed to a patient ace that includes: a plenum chamber; a seal-forming structure; a vent structure; and a oning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient’s head. The positioning and stabilising structure including at least one gas delivery tube to e the flow of air from a connection port and to deliver the flow of air to the ce of the patient’s airways via the seal-forming structure, the gas delivery tube being ucted and arranged to contact, in use, at least a region of the patient’s head superior to an otobasion superior of the patient’s head.

According to one aspect of the present technology there is provided a oning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically ive position on a patient’s head, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an ce to the patient’s airways for sealed delivery of a flow of air at a therapeutic re of at least 6 cmH2O above ambient air pressure throughout the patient’s respiratory cycle in use, the positioning and stabilising structure comprising: at least one gas delivery tube to receive the flow of air from a connection port on top of the patient’s head and to deliver the flow of air to the entrance of the patient’s airways via the seal-forming structure, the gas delivery tube being ucted and arranged to contact, in use, at least a region of the patient’s head superior to an otobasion superior of the patient’s head, the gas delivery tube comprising: a tube wall defining a hollow interior through which air is able to flow to the seal-forming structure, the tube wall having an extendable portion configured to be extended to vary a length of the gas delivery tube; wherein the extendable portion comprises an extension stiffness within the range of 0.2 to 0.35 N/mm.

P1415NZ7 / 506176NZDIV6 In examples of any of the aspects of any of the preceding paragraphs: (a) the extension stiffness of the extendable n is within the range of 0.25 to 0.3 N/mm; (b) the pair of gas ry tubes comprise a combined unextended length, measured along a centreline of a side of the pair of tubes configured to be patientfacing in use, within the range of 500 to 535 mm; (c) the combined unextended length is within the range of 510 to 525 mm;(d) the combined nded length is within the range of 512 to 522 mm; (e) the pair of gas delivery tubes comprise a combined unextended length, measured along a centreline of a side of the pair of tubes configured to be patient-facing in use, within the range of 460 to 500 mm; (f) the combined unextended length is within the range of 470 to 490 mm; (g) the combined unextended length is within the range of 475 to 485 mm; (h) the gas delivery tubes form a loop around the patient’s head together with a cushion module, the loop having an nded , measured along a centreline of a side of the gas delivery tubes and n module configured to be patient-facing in use, within the range of 510 to 610 mm; (i) the unextended length of the loop is within the range of 528 to 548 mm; (j), the unextended length of the loop is within the range of 535 to 541 mm; (k) the unextended length of the loop is within the range of 534 to 554 mm (l) the unextended length of the loop is within the range of 539 to 549 mm; (m) the unextended length of the loop is within the range of 541 to 561 mm; (n) the unextended length of the loop is within the range of 546 to 556 mm; (o) the unextended length of the loop is within the range of 564 to 584 mm; (p) the unextended length of the loop is within the range of 571 to 581 mm; (q) the unextended length of the loop is within the range of 577 to 597 mm; and/or (r) the unextended length of the loop is within the range of 582 to 592 ing to one aspect of the present technology there is provided a positioning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a t’s head, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways for sealed delivery of a flow of air at a therapeutic pressure of at least 6 cmH2O above ambient air pressure hout the patient’s respiratory cycle in use, the positioning and stabilising structure comprising: P1415NZ7 / 506176NZDIV6 at least one gas delivery tube to receive the flow of air from a connection port on top of the patient’s head and to deliver the flow of air to the entrance of the patient’s airways via the seal-forming structure, the at least one gas delivery tube being constructed and arranged to contact, in use, at least a region of the patient’s head superior to an ion superior of the patient’s head, the at least one gas delivery tube comprising: a superior tube portion configured, in use, to e a superior region of the patient’s head, the superior tube portion sing: a first end configured, in use, to overlie a superior n of the patient’s head at or proximate the sagittal plane of the patient’s head; a second end configured, in use, to overlie a side portion of the patient’s head; a stiffened portion between the first end and the second end configured to provide a higher resistance to relative movement between the first end and the second end in an anterior and/or posterior direction than in a superior and/or inferior direction in use; an inferior tube portion ted between the second end of the superior tube portion and the orming structure.

In examples of any of the aspects of any of the preceding aphs: (a) each or tube n comprises two stiffened portions; (b) the stiffened portions are provided to one or both of a side of the superior tube portion configured to be or in use and a side of the superior tube portion configured to be ior in use; (c) the superior tube portion comprises an extendable portion; (d) the extendable portion comprises an extendable concertina structure formed in a tube wall of the gas delivery tube; (e) the extendable tina structure comprises plurality of folds in the tube wall alternatingly forming a plurality of ridges and a plurality of grooves; (f) the stiffened portion comprises a plurality of connecting portions formed in the tube wall, each of the plurality of connecting portions connecting a pair of adjacent ridges; and/or (g) the stiffened portions are integrally formed with the superior tube portion.

P1415NZ7 / 506176NZDIV6 According to one aspect of the present technology there is provided a positioning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient’s head, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways for sealed delivery of a flow of air at a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient’s respiratory cycle in use, the positioning and stabilising structure sing: at least one gas delivery tube to receive the flow of air from a tion port on top of the patient’s head and to deliver the flow of air to the entrance of the patient’s s via the seal-forming structure, the at least one gas delivery tube being constructed and arranged to contact, in use, at least a region of the patient’s head superior to an otobasion or of the patient’s head, the at least one gas delivery tube sing a tube wall having an extendable concertina structure comprising: a plurality of folds in the tube wall alternatingly forming a plurality of ridges and a plurality of grooves, the folds able to be at least partially unfolded to increase a separation of the ridges to elongate the able concertina structure; and one or more ridge connecting ns provided to the tube wall, each of the one or more ridge ting portions connecting two or more adjacent ridges of the plurality of ridges and being configured to resist the tion of the ridges.

In es of any of the aspects of any of the preceding paragraphs: (a) each pair of nt ridges is ted by at least one ridge connecting portion of the one or more ridge connecting portions; (b) one or more pairs of adjacent ridges are connected by two ridge connecting portions; (c) each pair of adjacent ridges is connected by two ridge connecting portions; (d) one or more of the ridge connecting portions is located on a side of the gas delivery tube configured to be anterior-facing in use; (e) one or more of the ridge connecting portions is located on a side of the gas delivery tube configured to be posterior-facing in use; (f) each of the ridge connecting portions is spaced centrally between a side of the gas delivery tube configured to be P1415NZ7 / 506176NZDIV6 inferior-facing in use and a side of the gas delivery tube configured to be superiorfacing in use; (g) each pair of adjacent ridges is connected by one of the ridge connecting portion located on the side of the gas delivery tube configured to be anterior-facing in use; (h) each pair of adjacent ridges is connected by one of the ridge connecting portion located on the side of the gas ry tube configured to be posterior-facing; (i) the gas delivery tube comprises a non-extendable portion having an outer surface and each of the plurality of grooves is formed as a depression with respect to the outer surface of the non-extendable portion; (j) the gas delivery tube comprises a non-extendable n having an outer surface and each of the plurality of ridges is raised with respect to the outer surface of the non-extendable portion; (k) each of the plurality of grooves is located between a respective pair of ridge connecting portions, each ridge connecting portion of the pair of ridge connecting portions being located at a respective end of the respective ; (l) each of the plurality of grooves comprises a groove depth and each of the plurality of ridge ting portions ses a ridge connecting n height, the groove depth of each respective groove being equal to the ridge connecting portion height of each of the tive pair of ridge connecting portions located at the ends of the respective groove; (m) each ridge tion portion is an integrally formed portion of the tube wall; (n) the plurality of ridges, the plurality of grooves and the plurality of ridge connecting portions are integrally ; (o) each of the plurality of ridges comprises a curved ridge portion central to the tive ridge; (p) each of the plurality of grooves comprises a curved groove portion central to the respective groove; (q) each of the plurality of ridges comprises a pair of straight ridge portions provided at opposite ends of the respective ridge; (r) each of the plurality of ridge connecting portions connects the respective adjacent pair of ridges at the straight ridge portions of the ridge; (s) the gas delivery tube at the extendable concertina ure comprises a cross-section having a width and a height, the width being aligned in use substantially with the anterior-posterior directions, the width being larger than the height; (t) the width is at least twice as large as the height; and/or (u) the positioning and stabilising structure comprises two gas delivery tubes fluidly connected between the tion port and the seal-forming structure, each gas delivery tube extending, in use, across one of the patient’s cheek regions, the two gas delivery tubes being on different sides of the patient’s head.

P1415NZ7 / 506176NZDIV6 According to one aspect of the present technology there is provided a positioning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient’s head, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the t’s airways for sealed delivery of a flow of air at a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient’s respiratory cycle in use, the positioning and stabilising structure comprising: at least one gas delivery tube to receive the flow of air from a connection port on top of the t’s head and to deliver the flow of air to the entrance of the t’s airways via the seal-forming ure, the at least one gas delivery tube being constructed and arranged to t, in use, at least a region of the patient’s head or to an otobasion superior of the patient’s head, the at least one gas delivery tube comprising a tube wall having a hollow interior and having an extendable tina ure provided along a length of the gas delivery tube, the extendable concertina structure comprising: a plurality of folds in the tube wall forming a first alternating series of ridges and grooves along a non-patient-contacting side of the gas delivery tube and a second alternating series of ridges and grooves along a patientcontacting side of the gas delivery tube; wherein the first alternating series of ridges and grooves has a lesser extension stiffness than the second alternating series of ridges and grooves.

In examples: (a) the plurality of folds form, interior to the gas delivery tube, or ridges and interior grooves forming the first alternating series of ridges and grooves and the second alternating series of ridges and grooves; (b) each one of the interior s of the first alternating series is provided opposite a respective one of the interior grooves of the second alternating series across the interior of the gas delivery tube to form a plurality of opposing groove pairs, each opposing groove pair comprising: a first interior groove, being one interior groove of the first alternating series; and a second interior groove, being one or groove of the second alternating series; wherein the first interior groove comprises a greater groove depth than the second interior ; (c) the tube wall comprises a greater material P1415NZ7 / 506176NZDIV6 thickness at a base of the second interior groove of each opposing groove pair than at a base of the first interior groove of the respective opposing groove pair; (d) the material thickness of the tube wall at the base of each interior groove of the second alternating series reduces along the length of the gas delivery tube from a first end proximate the connection port to a second end; (e) the material thickness of the tube wall at the base of each interior groove of the first alternating series is substantially nt along the length of the gas delivery tube; (f) the groove depths of the interior s of the first and second alternating series of interior ridges and interior grooves reduce along the length of the gas delivery tube from a first end adjacent the connection port to a second end; and/or (g) the first interior groove of each d groove pair is joined to the second interior groove of the respective opposed groove pair at sides of the gas delivery tube between the non-patient-contacting side and the patient-contacting side.

According to one aspect of the t technology there is provided a positioning and stabilising structure to e a force to hold a seal-forming structure in a therapeutically ive position on a patient’s head, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways for sealed delivery of a flow of air at a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient’s respiratory cycle in use, the positioning and stabilising structure comprising: a pair of gas delivery tubes to receive the flow of air from a connection port on top of the patient’s head and to deliver the flow of air to the entrance of the t’s airways via the seal-forming structure, each of the pair of gas delivery tubes being constructed and ed to contact, in use, at least a region of the patient’s head superior to an ion or of the patient’s head, and each gas delivery tube comprising: a tube wall defining a hollow interior along the length of the gas delivery tube; a tab connected to the tube wall and configured, in use, to be located superior to the otobasion superior of the patient’s head; and P1415NZ7 / 506176NZDIV6 a slit formed in the tab, the slit spaced posteriorly in use from the tube wall, the slit comprising a superior end and an inferior end, wherein the superior end of the slit is spaced further from the tube wall than the inferior end of the slit; and a strap constructed and arranged to contact, in use, a region of the patient’s head inferior to or ying an occipital bone of the t’s head, the strap being configured to connect to and n the slits.

In examples of any of the aspects of any of the ing paragraphs: (a) each tab is integrally formed with a tive tube wall; (b) each tab has a superior edge and an inferior edge, the superior edge being longer than the inferior edge; (c) the inferior end of the slit is spaced from the tube wall by at least 5mm; (d) the inferior end of the slit is spaced from the tube wall at least 7mm; (e) the inferior end of the slit is spaced from the tube wall by 8mm or more; (f) the superior end of the slit is spaced from the tube wall by at least 8mm; (g) the superior end of the slit is spaced from the tube wall by at least 10mm; (h) the superior end of the slit is spaced from the tube wall by 12mm or more; (i) a midpoint along the slit is spaced from the tube wall by a spacing within the range of 5mm to 30mm; (j) the spacing is within the range of 7mm to 20mm; (k) the spacing is within the range of 8mm to 15mm; (l) the spacing is within the range of 9 to 11mm; (m) each gas delivery tube comprises an extendable tube n located superior in use to the tab of the respective gas delivery tube and a non-extendable tube section located inferior in use to the tab of the respective gas delivery tube; (n) each tab is joined to the tube wall of the respective gas delivery tube at the non-extendable tube section; (o) each slit is arcuate between the or end and the inferior end; (p) each slit is straight between the or end and the inferior end; and/or (q) each slit is ed perpendicular to the direction from the slit of a strap anchor region against which the strap is anchored around the patient’s head.

According to one aspect of the present technology there is provided a positioning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient’s head, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways for sealed delivery of a flow of air at a therapeutic P1415NZ7 / 506176NZDIV6 pressure of at least 6 cmH2O above ambient air pressure throughout the patient’s respiratory cycle in use, the positioning and stabilising structure comprising: a pair of gas delivery tubes to receive the flow of air from a connection port on top of the t’s head and to deliver the flow of air to the entrance of the patient’s s via the orming structure, each of the pair of gas delivery tubes being constructed and arranged to contact, in use, at least a region of the patient’s head superior to an otobasion superior of the patient’s head, and each gas delivery tube comprising: a tube wall configured, in use, to overlie the patient’s head along a path from a superior portion of the patient’s head to the seal forming ure passing between an eye and an ear of the patient; a tab connected to the tube wall and configured, in use, to be d superior to the otobasion superior of the patient’s head; and a slit formed in the tab and spaced posteriorly in use from a jacent portion of the path of the tube wall; wherein the slit has a posterosuperior-anteroinferior orientation in use and forms an oblique angle with a tangent of the path of the tube wall at the slit-adjacent portion; and a strap constructed and arranged to contact, in use, a region of the patient’s head inferior to or ying an occipital bone of the patient’s head, the strap being configured to connect to and between the slits.

In examples of any of the aspects of any of the preceding paragraphs: (a) each tab is integrally formed with a respective one of the tube walls; (b) each tab has a superior edge and an inferior edge in use, the superior edge being longer than the inferior edge; (c) each gas delivery tube comprises an extendable tube section superior to the tab of the respective gas delivery tube in use and a non-extendable tube n inferior to the tab of the respective gas delivery tube in use; (d) each tab is ted to the tube wall of the respective gas delivery tube at the non-extendable tube section; (e) each slit is arcuate n a superior end and an inferior end of the slit; (f) each P1415NZ7 / 506176NZDIV6 slit is straight between a superior end and an inferior end of the slit; (g) an inferior end of the slit is spaced from the tube wall by at least 5mm; (h) the inferior end of the slit is spaced from the tube wall at least 7mm (i) the inferior end of the slit is spaced from the tube wall by 8mm or more; (j) a superior end of the slit is spaced from the tube wall by at least 8mm; (k) the superior end of the slit is spaced from the tube wall by at least 10mm; (l) the superior end of the slit is spaced from the tube wall by 12mm or more; (m) the oblique angle is in the range of 10 to 20 degrees; (n) the oblique angle is in the range of 12 to 18 degrees; and/or (o) each slit is oriented perpendicular to the direction from the slit of a strap anchor region against which the strap is anchored around the t’s head.

According to one aspect of the present technology there is provided a positioning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient’s head, the seal-forming structure constructed and arranged to form a seal with a region of the t’s face surrounding an ce to the patient’s airways for sealed delivery of a flow of air at a therapeutic pressure of at least 6 cmH2O above ambient air pressure hout the patient’s respiratory cycle in use, the positioning and stabilising structure comprising: a pair of gas delivery tubes to receive the flow of air from a connection port on top of the patient’s head and to deliver the flow of air to the entrance of the patient’s airways via the orming structure, each of the pair of gas delivery tubes being constructed and arranged to contact, in use, at least a region of the patient’s head superior to an otobasion superior of the patient’s head, and each gas delivery tube comprising: a tube wall ured to overlie the patient’s head from a superior n of the t’s head to the seal forming structure passing between an eye and an ear of the t; and a tab connected to the tube wall and located superior to the otobasion superior of the patient’s head in use; an eyelet formed in the tab and located posteriorly to the tube wall in P1415NZ7 / 506176NZDIV6 a trough formed in the tab and located posteriorly to the eyelet; and a strap constructed and arranged to contact, in use, a region of the patient’s head inferior to or overlaying an occipital bone of the patient’s head, the strap being configured to connect to and between the eyelets of the pair of gas delivery tubes and to lie within the s formed in the tabs in use.

In es of any of the aspects of any of the preceding paragraphs: (a) the trough is formed in the tab between the eyelet and a posterior side of the tab; (b) the tab comprises an outwardly facing surface and the trough comprises a substantially planar surface formed as a depression with respect to the outwardly facing surface; (c) the trough is formed by a portion of the tab having a reduced material thickness in comparison to other portions of the tab; (d) the trough comprises a length approximately equal to the width of the strap; and/or (e) the eyelet is in the form of a slit.

According to one aspect of the present technology, there is provided a patient interface comprising: a plenum chamber pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum r including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient, a orming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways, said seal- forming ure having a hole therein such that the flow of air at said therapeutic pressure is delivered to at least an entrance to the patient’s nares, the seal-forming ure constructed and arranged to in said therapeutic pressure in the plenum r throughout the patient’s respiratory cycle in use; the positioning and stabilising structure according to any one of the above aspects; and P1415NZ7 / 506176NZDIV6 a vent ure to allow a uous flow of gases exhaled by the patient from an interior of the plenum chamber to ambient, said vent structure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use; wherein the patient interface is configured to allow the t to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient ace is configured to leave the patient’s mouth uncovered.

Another aspect of certain forms of the present technology is a system for treating a respiratory disorder comprising a patient interface according to any one or more of the other aspects of the present technology, an air circuit and a source of air at positive pressure.

Another aspect of one form of the present technology is a patient interface that is moulded or otherwise constructed with a perimeter shape which is complementary to that of an intended wearer.

Another aspect of certain forms of the present technology is a t interface comprising a seal-forming structure configured to leave the patient’s mouth uncovered in use.

Another aspect of n forms of the present technology is a patient interface comprising a seal-forming structure configured so that no part of the sealforming structure enters the mouth in use.

Another aspect of certain forms of the present technology is a patient interface comprising a orming structure configured so that the orming structure does not extend internally of the patient’s s.

Another aspect of certain forms of the present technology is a patient interface comprising a seal-forming structure configured so that the seal-forming ure does not extend below a mental protuberance region in use.

Another aspect of n forms of the t technology is a patient interface constructed and arranged to leave a patient’s eyes uncovered in use.

P1415NZ7 / 506176NZDIV6 Another aspect of certain forms of the present technology is a patient interface constructed and arranged to allow a patient to breathe ambient air in the event of a power failure.

Another aspect of certain forms of the present technology is a patient interface comprising a seal forming structure configured to form a seal on an underside of a patient’s nose without contacting a nasal bridge region of the t’s nose.

Another aspect of certain forms of the present technology is a patient interface comprising a vent and a plenum chamber, wherein the patient interface is constructed and arranged so that gases from an interior of the plenum chamber may pass to ambient via the vent.

Another aspect of certain forms of the present technology is a patient interface constructed and ed so that a t may lie comfortably in a side or lateral sleeping position, in use of the patient interface.

Another aspect of certain forms of the present technology is a patient interface ucted and arranged so that a patient may lie comfortably in a supine sleeping position, in use of the patient interface.

Another aspect of certain forms of the present technology is a t interface constructed and arranged so that a patient may lie comfortably in a prone ng position, in use of the patient interface.

An aspect of certain forms of the present technology is a medical device that is easy to use, e.g. by a person who does not have medical training, by a person who has limited dexterity, vision or by a person with limited ence in using this type of l .

An aspect of one form of the present technology is a patient interface that may be washed in a home of a patient, e.g., in soapy water, without requiring specialised cleaning ent.

Of course, portions of the aspects may form sub-aspects of the present technology. Also, various ones of the sub-aspects and/or s may be combined in P1415NZ7 / 506176NZDIV6 various manners and also constitute additional s or sub-aspects of the present technology.

Other features of the technology will be apparent from eration of the information contained in the ing detailed description, abstract, drawings and claims. 4 BRIEF PTION OF THE DRAWINGS The present technology is rated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements including: 4.1 TREATMENT SYSTEMS Fig. 1A shows a system including a patient 1000 wearing a patient interface 3000, in the form of nasal pillows, receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device 4000 is humidified in a humidifier 5000, and passes along an air circuit 4170 to the patient 1000. A bed partner 1100 is also shown. The patient is sleeping in a supine sleeping on.

Fig. 1B shows a system including a patient 1000 g a patient interface 3000, in the form of a nasal mask, receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device is humidified in a humidifier 5000, and passes along an air circuit 4170 to the patient 1000.

Fig. 1C shows a system including a patient 1000 wearing a patient interface 3000, in the form of a full-face mask, receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device is humidified in a fier 5000, and passes along an air circuit 4170 to the patient 1000. The patient is sleeping in a side sleeping on. 4.2 RESPIRATORY SYSTEM AND FACIAL ANATOMY Fig. 2A shows an overview of a human respiratory system including the nasal and oral cavities, the larynx, vocal folds, oesophagus, trachea, bronchus, lung, alveolar sacs, heart and diaphragm.

P1415NZ7 / 506176NZDIV6 Fig. 2B shows a view of a human upper airway ing the nasal cavity, nasal bone, lateral nasal cartilage, greater alar cartilage, nostril, lip superior, lip inferior, larynx, hard palate, soft palate, oropharynx, tongue, epiglottis, vocal folds, agus and trachea.

Fig. 2C is a front view of a face with several features of e y identified including the lip superior, upper vermilion, lower vermilion, lip inferior, mouth width, endocanthion, a nasal ala, nasolabial sulcus and cheilion. Also indicated are the directions superior, inferior, radially inward and ly outward.

Fig. 2D is a side view of a head with several features of e anatomy identified including glabella, sellion, pronasale, subnasale, lip superior, lip inferior, supramenton, nasal ridge, alar crest point, otobasion superior and otobasion inferior.

Also ted are the directions superior & inferior, and anterior & posterior.

Fig. 2E is a further side view of a head. The approximate locations of the Frankfort horizontal and nasolabial angle are indicated. The coronal plane is also indicated.

Fig. 2F shows a base view of a nose with several features identified ing naso-labial sulcus, lip inferior, upper Vermilion, naris, subnasale, columella, pronasale, the major axis of a naris and the ittal plane.

Fig. 2G shows a side view of the superficial features of a nose.

Fig. 2H shows subcutaneal structures of the nose, including lateral cartilage, septum cartilage, greater alar cartilage, lesser alar cartilage, sesamoid cartilage, nasal bone, mis, adipose tissue, frontal process of the maxilla and atty tissue.

Fig. 2I shows a medial dissection of a nose, approximately several millimeters from the midsagittal plane, amongst other things showing the septum cartilage and medial crus of greater alar cartilage.

Fig. 2J shows a front view of the bones of a skull including the frontal, nasal and zygomatic bones. Nasal concha are ted, as are the maxilla, and mandible.

P1415NZ7 / 506176NZDIV6 Fig. 2K shows a lateral view of a skull with the outline of the surface of a head, as well as l muscles. The following bones are shown: l, sphenoid, nasal, zygomatic, maxilla, mandible, parietal, temporal and occipital. The mental protuberance is indicated. The following muscles are shown: digastricus, masseter, sternocleidomastoid and trapezius.

Fig. 2L shows an anterolateral view of a nose. 4.3 PATIENT INTERFACE Fig. 3A shows a patient interface in the form of a nasal mask in accordance with one form of the present technology.

Fig. 3B shows a schematic of a cross-section through a ure at a point. An outward normal at the point is indicated. The curvature at the point has a positive sign, and a relatively large magnitude when compared to the magnitude of the curvature shown in Fig. 3C.

Fig. 3C shows a schematic of a section through a structure at a point. An outward normal at the point is indicated. The curvature at the point has a positive sign, and a relatively small ude when ed to the magnitude of the curvature shown in Fig. 3B.

Fig. 3D shows a schematic of a cross-section through a structure at a point. An outward normal at the point is indicated. The curvature at the point has a value of zero.

Fig. 3E shows a schematic of a cross-section through a structure at a point. An outward normal at the point is indicated. The curvature at the point has a negative sign, and a relatively small magnitude when compared to the magnitude of the curvature shown in Fig. 3F.

Fig. 3F shows a schematic of a cross-section through a structure at a point.

An outward normal at the point is indicated. The curvature at the point has a negative sign, and a relatively large magnitude when compared to the ude of the curvature shown in Fig. 3E.

Z7 / 506176NZDIV6 Fig. 3G shows a cushion for a mask that includes two pillows. An exterior surface of the cushion is indicated. An edge of the surface is indicated. Dome and saddle regions are indicated.

Fig. 3H shows a cushion for a mask. An exterior surface of the cushion is indicated. An edge of the surface is indicated. A path on the surface between points A and B is ted. A straight line distance between A and B is indicated. Two saddle regions and a dome region are indicated.

Fig. 3I shows the e of a structure, with a one dimensional hole in the surface. The illustrated plane curve forms the boundary of a one dimensional hole.

Fig. 3J shows a cross-section through the structure of Fig.3I. The illustrated surface bounds a two dimensional hole in the structure of Fig. 3I.

Fig. 3K shows a perspective view of the structure of Fig. 3I, including the two dimensional hole and the one ional hole. Also shown is the surface that bounds a two dimensional hole in the structure of Fig. 3I.

Fig. 3L shows a mask having an inflatable r as a cushion.

Fig. 3M shows a cross-section through the mask of Fig. 3L, and shows the interior surface of the bladder. The interior surface bounds the two dimensional hole in the mask.

Fig. 3N shows a further cross-section through the mask of Fig. 3L. The interior e is also indicated.

Fig. 3O illustrates a left-hand rule.

Fig. 3P illustrates a right-hand rule.

Fig. 3Q shows a left ear, including the left ear helix.

Fig. 3R shows a right ear, including the right ear helix.

Fig. 3S shows a right-hand helix.

P1415NZ7 / 506176NZDIV6 Fig. 3T shows a view of a mask, including the sign of the torsion of the space curve d by the edge of the sealing ne in different regions of the mask.

Fig. 3U shows a view of a plenum chamber 3200 showing a sagittal plane and a mid-contact plane.

Fig. 3V shows a view of a posterior of the plenum chamber of Fig. 3U.

The direction of the view is normal to the mid-contact plane. The sagittal plane in Fig. 3V bisects the plenum r into left-hand and right-hand sides.

Fig. 3W shows a cross-section through the plenum r of Fig. 3V, the cross-section being taken at the al plane shown in Fig. 3V. A ‘mid-contact’ plane is shown. The mid-contact plane is perpendicular to the sagittal plane. The orientation of the mid-contact plane corresponds to the orientation of a chord which lies on the sagittal plane and just touches the cushion of the plenum chamber at two points on the sagittal plane: a superior point and an inferior point. ing on the geometry of the cushion in this region, the mid-contact plane may be a tangent at both the superior and inferior points.

Fig. 3X shows the plenum chamber 3200 of Fig. 3U in position for use on a face. The sagittal plane of the plenum chamber 3200 generally coincides with the midsagittal plane of the face when the plenum chamber is in position for use. The mid-contact plane corresponds generally to the ‘plane of the face’ when the plenum chamber is in position for use. In Fig. 3X the plenum chamber 3200 is that of a nasal mask, and the superior point sits approximately on the sellion, while the inferior point sits on the lip superior. 4.4 RPT DEVICE Fig. 4A shows an RPT device in accordance with one form of the present technology.

Fig. 4B is a schematic diagram of the tic path of an RPT device in accordance with one form of the t technology. The directions of upstream and downstream are indicated with reference to the blower and the patient interface. The blower is defined to be upstream of the patient interface and the patient interface is P1415NZ7 / 506176NZDIV6 defined to be downstream of the blower, regardless of the actual flow direction at any particular moment. Items which are located within the pneumatic path between the blower and the patient interface are downstream of the blower and upstream of the patient interface. 4.5 FIER Fig. 5A shows an isometric view of a humidifier in accordance with one form of the present logy.

Fig. 5B shows an isometric view of a humidifier in accordance with one form of the present logy, showing a humidifier reservoir 5110 removed from the humidifier reservoir dock 5130. 4.6 BREATHING WAVEFORMS Fig. 6A shows a model typical breath waveform of a person while sleeping. 4.7 SCREENING, DIAGNOSIS AND MONITORING SYSTEMS Fig. 7A shows a patient undergoing polysomnography (PSG). The t is sleeping in a supine sleeping position.

Fig. 7B shows a monitoring apparatus for monitoring the condition of a patient. The patient is sleeping in a supine ng position. 4.8 ULAR EXAMPLES OF THE PRESENT TECHNOLOGY Fig. 8A is a perspective view illustration of a patient interface 3000 ing to one example of the present technology while worn by a patient 1000.

Fig. 8B is a front view illustration of the patient interface 3000 shown in Fig. 8A.

Fig. 8C is a side view illustration of the patient interface 3000 shown in Fig. 8A.

Fig. 8D is another side view illustration of the patient interface 3000 shown in Fig. 8A.

P1415NZ7 / 506176NZDIV6 Fig. 9A is a perspective view illustration of the patient interface 3000 of Fig. 8A in ion.

Fig. 9B is a rear perspective view illustration of the patient interface 3000 of Fig. 8A in isolation.

Fig. 9C is a top view illustration of the t interface 3000 of Fig. 8A in isolation.

Fig. 10A shows a plan view of components of a positioning and stabilising structure 3300 according to one example of the present technology.

Fig. 10B shows a cross section view B-B of a portion of the positioning and stabilising ure 3300 of Fig. 10A.

Fig. 10C shows a cross section view C-C of a non-extendable portion of the positioning and stabilising structure 3300 of Fig. 10A.

Fig. 10D shows a plan view of a portion of an extendable portion of the positioning and stabilising ure 3300 of Fig. 10A.

Fig. 10E shows a cross section view E-E of an extendable portion of the positioning and stabilising structure the 3300 of Fig. 10D.

Fig. 10F shows a front view of a portion of an extendable portion of the positioning and stabling structure 3300 of Fig. 10A.

Fig. 10G shows a front view of an extendable portion of the positioning and stabilising ure 3300 of Fig. 10A in a straightened uration.

Fig. 10H shows a front view of the extendable portion shown in Fig. 10G in a curved configuration.

Fig. 10I shows a perspective view of the extendable portion shown in Fig. 10G in a curved configuration.

Fig. 10J shows a top view of the extendable n shown in Fig. 10G in a curved configuration.

P1415NZ7 / 506176NZDIV6 Fig. 11A shows a side view of a tab of the positioning and stabilising structure 3300 of Fig. 10A.

Fig. 11B shows another side view of a tab of the positioning and stabilising structure 3300 of Fig. 10A Fig. 11C is a perspective view of the tab of Fig. 11A.

Fig. 12A is ctive view of a patient interface 3000 according to another e of the present technology while worn by a patient 1000.

Fig. 12B is a perspective view of the t interface 3000 of Fig. 12A in isolation.

Fig. 12C is a front view of the patient interface 3000 of Fig. 12A.

Fig. 12D is a rear view of the patient interface 3000 of Fig. 12A.

Fig. 12E is a plan view of the patient interface 3000 of Fig. 12A.

Fig. 12F is a side view of the patient interface 3000 of Fig. 12A.

Fig. 13 is a perspective view of a portion of a positioning and stabilising structure 3300 of a t ace according to another example of the present technology.

DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY Before the present technology is described in further , it is to be understood that the technology is not limited to the particular examples described herein, which may vary. It is also to be understood that the terminology used in this disclosure is for the purpose of describing only the particular examples discussed herein, and is not intended to be limiting.

The following ption is provided in relation to various examples which may share one or more common characteristics and/or features. It is to be understood that one or more features of any one e may be combinable with one or more features of another example or other examples. In addition, any single P1415NZ7 / 506176NZDIV6 feature or combination of features in any of the examples may constitute a further example. .1 THERAPY In one form as shown in Fig. 1A, the present technology comprises a method for treating a atory disorder comprising the step of ng positive pressure to the entrance of the s of a patient 1000.

In certain examples of the present technology, a supply of air at positive pressure is provided to the nasal passages of the patient via one or both nares.

In certain examples of the present technology, mouth breathing is limited, restricted or prevented. .2 TREATMENT SYSTEMS In one form, the present technology comprises an tus or device for treating a respiratory disorder. The apparatus or device may comprise an RPT device 4000 for supplying pressurised air to the patient 1000 via an air circuit 4170 to a patient interface 3000. Figs. 1A, 1B and 1C illustrate treatment systems that utilise patent interfaces 3000 with RPT devices 4000 and humidifiers 5000. .3 PATIENT INTERFACE With reference to Fig. 3A, a non-invasive patient interface 3000 in accordance with one aspect of the present technology comprises the following functional aspects: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilising structure 3300, a vent 3400, one form of connection port 3600 for connection to air circuit 4170, and a forehead support 3700. In some forms a functional aspect may be provided by one or more physical components. In some forms, one physical component may provide one or more functional aspects. In use the seal-forming structure 3100 is arranged to surround an entrance to the airways of the t so as to facilitate the supply of air at positive pressure to the airways.

As shown in Figs. 8A-9C, a non-invasive patient interface 3000 in ance with one aspect of the present technology comprises the following functional aspects: a seal-forming ure 3100, a plenum chamber 3200, a positioning and ising ure 3300, a vent 3400 and one form of connection P1415NZ7 / 506176NZDIV6 port 3600 for connection to an air t (e.g. the air circuit 4170 shown in Figs. 1A- 1C). In this e, the seal-forming structure 3100 and the plenum chamber 3200 are provided by a cushion module 3150.

If a patient ace is unable to comfortably deliver a minimum level of positive pressure to the airways, the patient interface may be unsuitable for respiratory pressure therapy.

The patient interface 3000 in accordance with one form of the present logy is constructed and arranged to be able to provide a supply of air at a positive pressure of at least 6 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the present technology is constructed and arranged to be able to provide a supply of air at a positive re of at least 10 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the present technology is constructed and arranged to be able to provide a supply of air at a positive pressure of at least 20 cmH2O with respect to ambient. .3.1 Seal-forming structure In one form of the present logy, a seal-forming structure 3100 provides a target seal-forming region, and may additionally provide a cushioning on. The target seal-forming region is a region on the orming structure 3100 where sealing may occur. The region where sealing actually occurs- the actual sealing surface- may change within a given treatment session, from day to day, and from t to patient, depending on a range of factors including for example, where the patient interface was placed on the face, tension in the oning and stabilising structure and the shape of a patient’s face.

In one form the target seal-forming region is located on an outside surface of the seal-forming structure 3100.

In certain forms of the present technology, the seal-forming structure 3100 is constructed from a biocompatible material, e.g. silicone rubber.

P1415NZ7 / 506176NZDIV6 A seal-forming ure 3100 in accordance with the present technology may be constructed from a soft, flexible, resilient material such as silicone.

In certain forms of the present technology, a system is provided comprising more than one a seal-forming structure 3100, each being configured to correspond to a different size and/or shape range. For example, the system may se one form of a orming structure 3100 suitable for a large sized head, but not a small sized head and another suitable for a small sized head, but not a large sized head. .3.1.1 g mechanisms In one form, the seal-forming structure 3100 includes a sealing flange utilizing a pressure ed sealing mechanism. In use, the sealing flange can readily respond to a system positive pressure in the interior of the plenum chamber 3200 acting on its underside to urge it into tight sealing engagement with the face. The pressure assisted mechanism may act in conjunction with elastic tension in the positioning and stabilising structure.

In one form, the orming structure 3100 comprises a sealing flange and a support flange. The sealing flange comprises a relatively thin member with a thickness of less than about 1mm, for example about 0.25mm to about 0.45mm, which extends around the ter of the plenum chamber 3200. Support flange may be relatively thicker than the sealing flange. The support flange is disposed between the sealing flange and the marginal edge of the plenum chamber 3200, and extends at least part of the way around the perimeter. The support flange is or includes a springlike element and ons to t the sealing flange from buckling in use.

In one form, the seal-forming structure may comprise a compression sealing portion or a gasket sealing portion. In use the compression sealing n, or the gasket sealing portion is constructed and arranged to be in compression, e.g. as a result of elastic tension in the positioning and stabilising structure.

In one form, the seal-forming structure comprises a tension portion. In use, the tension portion is held in n, e.g. by adjacent regions of the sealing flange.

P1415NZ7 / 506176NZDIV6 In one form, the seal-forming structure comprises a region having a tacky or adhesive surface, and/or having a higher coefficient of friction compared to other surfaces.

In certain forms of the t technology, a seal-forming structure may comprise one or more of a pressure-assisted sealing flange, a compression sealing portion, a gasket sealing portion, a tension portion, and a portion having a tacky or ve surface. .3.1.2 Nose bridge or nose ridge region In one form, the vasive patient interface 3000 comprises a sealforming structure that forms a seal in use on a nose bridge region or on a nose-ridge region of the t's face.

In one form, the seal-forming structure includes a saddle-shaped region constructed to form a seal in use on a nose bridge region or on a nose-ridge region of the patient's face. .3.1.3 Upper lip region In one form, the non-invasive patient interface 3000 comprises a sealforming structure that forms a seal in use on an upper lip region (that is, the lip superior) of the t's face.

In one form, the orming structure includes a saddle-shaped region constructed to form a seal in use on an upper lip region of the patient's face. .3.1.4 Chin-region In one form the non-invasive patient interface 3000 comprises a sealforming structure that forms a seal in use on a chin-region of the patient's face.

In one form, the seal-forming structure es a saddle-shaped region constructed to form a seal in use on a chin-region of the patient's face.

P1415NZ7 / 506176NZDIV6 Forehead region In one form, the seal-forming structure that forms a seal in use on a forehead region of the t's face. In such a form, the plenum r may cover the eyes in use. .3.1.6 Nasal pillows In one form the seal-forming structure 3100 of the non-invasive patient interface 3000 comprises a pair of nasal puffs, or nasal pillows, each nasal puff or nasal pillow being ucted and arranged to form a seal with a respective naris of the nose of a patient. Figs. 12A-F show a patient interface 3000 having a seal-forming structure 3100 provided by a pillows cushion module 3160. The pillows cushion module 3160 comprises a pair of nasal pillows 3165. In this example, the same positioning structure 3300 as shown in Figs. 8A-9C is used to hold the pillows n module 3160 in sealing contact with the patient’s nose. The same concepts and features of the positioning and stabilising structure 3300 described with reference to the cradle cushion module 3150 may be applied to a positioning and stabilising structure 3300 configured to be used with the pillows cushion module 3160 (or another type of cushion module such as a full face n module, oro-nasal cushion module, ultra-compact full face cushion module, nasal cushion module and the like).

Nasal pillows 3165 in accordance with an aspect of the present technology e: a frusto-cone, at least a portion of which forms a seal on an underside of the patient's nose, a stalk, a flexible region on the underside of the frusto-cone and connecting the frusto-cone to the stalk. In addition, the structure to which the nasal pillow of the present technology is connected includes a flexible region adjacent the base of the stalk. The le regions can act in concert to facilitate a universal joint structure that is accommodating of relative movement both displacement and angular of the frusto-cone and the structure to which the nasal pillow is connected. For example, the frusto-cone may be y displaced towards the structure to which the stalk is connected. .3.1.7 Nasal Cradle In one form, for example as shown in Figs. 8A-9C, the seal-forming structure 3100 is configured to form a seal in use with the underside of the nose P1415NZ7 / 506176NZDIV6 around the nares and optionally with the lip superior of the patient 1000. This type of orming structure may be ed to as a “cradle cushion” or asal mask”.

The shape of the seal-forming structure may be configured to match or y follow the underside of the patient’s nose, i.e. the profile and angle of the seal-forming structure may be substantially parallel to the patient’s naso-labial angle. In one form of nasal cradle cushion, the seal-forming structure ses a bridge portion defining two orifices, each of which, in use, supplies air or breathable gas to a different one of the t’s nares. The bridge portion may be configured to contact or seal against the patient’s lla in use. In some forms of the technology, the seal-forming structure 3100 is configured to form a seal on an underside of the patient’s nose without contacting a nasal bridge region of the patient’s nose. In some examples, patient ace may comprise a seal-forming structure 3100 in the form of a cradle cushion as described in PCT Application No. , filed March 29, 2018, the entire contents of which are incorporated herein by reference. .3.1.8 Nasal Mask Cushion In one form, the non-invasive patient interface 3000 comprises a sealforming portion that forms a seal in use on an upper lip region (that is, the lip superior), a nasal bridge region and a cheek region of the patient's face. This is the case, for e, with the patient interface 3000 shown in Fig. 1B. This seal-forming portion delivers a supply of air or breathable gas to both nares of t 1000 through a single orifice. This type of seal-forming structure may be referred to as a “nasal cushion” or “nasal mask”. In some examples of the present technology, the positioning and stabilising structure 3300 shown in Figs. 8A-9C may be utilised to hold a nasal cushion in sealing position on a patient’s face. .3.1.9 Full-face Mask Cushion In one form the patient interface 3000 comprises a seal-forming portion that forms a seal in use on a chin-region, a nasal bridge region and a cheek region of the patient's face. This is the case, for example, with the patient interface 3000 shown in Fig. 1C. This orming portion delivers a supply of air or breathable gas to both nares and mouth of patient 1000 through a single orifice. This type of seal-forming ure may be referred to as a “full-face mask”. In some examples of the present P1415NZ7 / 506176NZDIV6 technology, the positioning and stabilising structure 3300 shown in Figs. 8A-9C may be utilised to hold a full-face n in g position on a patient’s face. .3.1.10 Oronasal Mask Cushion In another form the patient ace 3000 comprises a nasal seal-forming structure in the manner of a nasal cushion or nasal cradle cushion and an oral sealforming structure that is configured to form a seal in use around the mouth of a patient (which may be ed to as a “mouth cushion” or “oral mask”). In such a mask air or able gas is supplied in use through separate orifices to the patient’s nares and the patient’s mouth. This type of seal-forming structure 3100 may be referred to as an “oronasal cushion” or “ultra-compact full face cushion”. In one form, the nasal seal- forming structure and oral seal-forming structure are integrally formed as a single component. In some examples, patient ace may se a seal-forming structure 3100 in the form of a cradle cushion as described in US Patent Application No. 62/649,376, the entire contents of which are incorporated herein by reference.

The plenum chamber 3200 has a perimeter that is shaped to be complementary to the surface contour of the face of an average person in the region where a seal will form in use. In use, a marginal edge of the plenum r 3200 is positioned in close proximity to an adjacent surface of the face. Actual contact with the face is provided by the seal-forming structure 3100. The seal-forming structure 3100 may extend in use about the entire perimeter of the plenum chamber 3200. In some forms, the plenum chamber 3200 and the seal-forming structure 3100 are formed from a single homogeneous piece of material.

In certain forms of the present logy, such as in the patient interface 3000 of Figs 8A-9C, the plenum chamber 3200 does not cover the eyes of the patient in use. In other words, the eyes are outside the pressurised volume defined by the plenum chamber. Such forms tend to be less obtrusive and / or more comfortable for the wearer, which can improve compliance with therapy.

In n forms of the present technology, the plenum chamber 3200 is constructed from a transparent material, e.g. a transparent polycarbonate. The use of a transparent material can reduce the iveness of the patient interface, and help P1415NZ7 / 506176NZDIV6 improve ance with therapy. The use of a transparent material can aid a clinician to observe how the patient interface is located and oning.

In certain forms of the present technology, the plenum chamber 3200 is constructed from a translucent material. The use of a translucent material can reduce the obtrusiveness of the patient interface, and help improve compliance with therapy. .3.2 Positioning and stabilising structure The seal-forming structure 3100 of the patient interface 3000 of the present technology may be held in sealing position in use by the positioning and stabilising structure 3300. oning and stabilising structure 3300 may be ed to as “headgear” since it engages the patient’s head in order to hold the t interface 3000 in a sealing position.

In one form the positioning and ising structure 3300 provides a retention force at least ient to overcome the effect of the positive pressure in the plenum chamber 3200 to lift off the face.

In one form the positioning and stabilising structure 3300 provides a retention force to overcome the effect of the gravitational force on the t interface 3000.

In one form the positioning and stabilising structure 3300 es a retention force as a safety margin to overcome the potential effect of disrupting forces on the patient interface 3000, such as from tube drag, or accidental erence with the patient interface.

In one form of the present technology, a positioning and stabilising structure 3300 is provided that is configured in a manner consistent with being worn by a patient while sleeping. In one example the positioning and stabilising structure 3300 has a low profile, or cross-sectional thickness, to reduce the ved or actual bulk of the apparatus. In one example, the positioning and stabilising structure 3300 comprises at least one strap having a rectangular cross-section. In one example the positioning and stabilising structure 3300 comprises at least one flat strap.

P1415NZ7 / 506176NZDIV6 In one form of the present technology, a positioning and stabilising structure 3300 is provided that is configured so as not to be too large and bulky to prevent the patient from lying in a supine sleeping position with a back region of the patient’s head on a pillow.

In one form of the present technology, a positioning and stabilising structure 3300 is provided that is configured so as not to be too large and bulky to prevent the patient from lying in a side sleeping position with a side region of the patient’s head on a pillow.

In one form of the present technology, a oning and stabilising structure 3300 is ed with a decoupling portion located n an or portion of the positioning and stabilising structure 3300, and a posterior portion of the positioning and stabilising structure 3300. The decoupling portion does not resist compression and may be, e.g. a flexible or floppy strap. The decoupling portion is constructed and arranged so that when the t lies with their head on a pillow, the presence of the decoupling portion prevents a force on the posterior n from being transmitted along the positioning and stabilising ure 3300 and disrupting the seal.

In one form of the present technology, a positioning and stabilising structure 3300 comprises a strap 3310 ucted from a laminate of a fabric tcontacting layer, a foam inner layer and a fabric outer layer. In one form, the foam is porous to allow moisture, (e.g., sweat), to pass h the strap 3310. The strap 3310 may be breathable to allow moisture vapour to be transmitted through the strap. In one form, the fabric outer layer comprises loop material to engage with a hook material portion.

In certain forms of the t technology, a positioning and stabilising structure 3300 comprises a strap that is extensible, e.g. resiliently extensible. For example the strap may be configured in use to be in tension, and to direct a force to draw a seal-forming structure into sealing contact with a portion of a patient’s face, in some examples in combination with other straps or other structures. In an example the strap may be configured as a tie.

P1415NZ7 / 506176NZDIV6 A tie will be understood to be a structure designed to resist tension. In use, a tie is part of the positioning and stabilising structure 3300 that is under tension.

Some ties will impart an elastic force as a result of this n, as will be described.

A tie may act to maintain the seal-forming structure 3100 in a therapeutically ive position on the patient’s head.

In one form of the present technology, the oning and stabilising structure comprises a first tie, the first tie being constructed and arranged so that in use at least a portion of an inferior edge thereof passes superior to an otobasion superior of the patient’s head and overlays a n of a parietal bone and/or l bone without overlaying the occipital bone. The first tie may be provided, for example, as part of a patient interface that comprises a cradle cushion, nasal pillows, nasal cushion, full-face cushion or an oronasal cushion. For example, as shown in Figs. 8A-9C, the positioning and stabilising structure 3300 ses a first tie in the form of tubes 3350 which lie over the top of the patient’s head.

In one form of the present technology suitable for a nasal-only mask or for a full-face mask, the positioning and stabilising structure 3300 includes a second tie, the second tie being constructed and arranged so that in use at least a portion of a superior edge thereof passes inferior to an otobasion inferior of the patient’s head and overlays or lies inferior to the occipital bone of the patient’s head. The second tie may be provided, for example, as part of a patient interface that comprises a cradle cushion, nasal pillows, full-face cushion, nasal cushion or an oronasal cushion. As shown in Figures 8A-9C, the positioning and stabilising structure 3300 comprises a second tie in the form of a strap 3310 that lies against ior surfaces of the patient’s head.

In one form of the present technology suitable for a nasal-only mask or for a full-face mask or oronasal mask, the positioning and stabilising structure 3300 includes a third tie that is configured to anchor against ior surfaces of the patient’s neck. Additionally, in some forms the positioning and ising ure comprises a fourth tie that is constructed and arranged to onnect the second tie and the third tie to reduce a tendency of the second tie and the third tie to move apart from one another.

P1415NZ7 / 506176NZDIV6 In certain forms of the present technology, a positioning and stabilising structure 3300 comprises a strap that is bendable and e.g. non-rigid. An advantage of this aspect is that the strap is more comfortable for a patient to lie upon while the patient is sleeping. As shown in Figs. 8A-9C, the positioning and stabilising structure 3300 comprises a strap 3310 that is bendable. The strap 3310 may be considered a backstrap. The strap 3310 is sufficiently flexible to pass around the back of the patient’s head and lie comfortably against the patient’s head, even when under tension in use.

In certain forms of the present technology, a system is provided comprising more than one positioning and stabilizing ure 3300, each being configured to provide a retaining force to correspond to a different size and/or shape range. For example, the system may comprise one form of positioning and izing structure 3300 suitable for a large sized head, but not a small sized head, and another suitable for a small sized head, but not a large sized head. .3.2.1 Headgear tubing In some forms of the present technology, the positioning and stabilising structure 3300 comprises one or more tubes 3350 that r pressurised air received from a conduit forming part of the air circuit 4170 from the RPT device to the patient’s airways, for e h the plenum chamber 3200 and seal-forming structure 3100. In the form of the present technology illustrated in Figs. 8A-9C, the positioning and stabilising structure 3300 ses two tubes 3350 that deliver air to the orming structure 3100 from the air circuit 4170. The tubes 3350 are an integral part of the positioning and stabilising structure 3300 of patient interface 3000 to position and stabilise the seal-forming structure 3100 of the patient ace to the appropriate part of the patient’s face (for example, the nose and/or mouth). This allows the conduit of air circuit 4170 providing the flow of pressurised air to connect to a tion port 3600 of the t interface in a position other than in front of the patient’s face which may be unsightly to some . While a pair of tubes 3350 have some advantages (described below), in some examples, the positioning and stabilising structure 3300 comprises only a single tube 3350 configured to overlie the patient’s head on one side. A strap or other stabilising ent may be provided to the other side of the patient’s head between the top end of the single tube 3350 and P1415NZ7 / NZDIV6 the seal-forming structure 3100, to provide balanced forces on the orming structure 3100.

Since air can be contained and passed through ar tubing 3350 in order to deliver pressurised air from the air circuit 4170 to the patient’s airways, the positioning and stabilising structure 3300 may be described as being able. It will be understood that an inflatable positioning and stabilising structure 3300 does not require all components of the positioning and stabilising structure 3300 to be inflatable. For example, in the example shown in Figs. 8A-9C and 12A-F, the positioning and stabilising structure 3300 comprises the headgear tubing 3350, which is inflatable, and the strap 3310, which is not inflatable.

In certain forms of the present technology, the patient interface 3000 may comprise a connection port 3600 located proximal a top, side or rear portion of a patient’s head. For example, in the form of the present technology rated in Figs. 8A-9C, the connection port 3600 is located on top of the patient’s head. In this example the t interface 3000 comprises an elbow 3610 to which the connection port 3600 is provided. The elbow 3610 may swivel with t to the positioning and stabilising structure 3300 and order to decouple movement of a t connected to the connection port 3600 from the positioning and stabilising structure 3300.

Additionally, or alternatively, a conduit connected to the connection port 3600 may swivel with respect to the elbow 3610. In the illustrated example, elbow 3610 comprises a ling conduit connector to which a conduit of the air circuit 4170 is able to connect such that the conduit can rotate about its longitudinal axis with respect to the elbow 3610. The connection port 3600 may comprise fluid connection opening 3390, for example as shown in Fig. 10A and 10B. In some examples the air t 4170 may connect to the fluid connection opening 3390. The elbow 3610 may bly connect to the fluid connection opening or to a ring ed in the fluid connection opening.

Patient interfaces in which the connection port is not positioned in front of the patient’s face may be advantageous as some ts find a conduit that connects to a patient interface in front of the face to be unsightly and obtrusive. For example, a conduit connecting to a patient interface in front of the face may be prone to being tangled up in bedclothes or bed linen, particularly if the conduit extends downwardly P1415NZ7 / 506176NZDIV6 from the t interface in use. Forms of the technology with a patient interface with a connection port oned proximate the top of the patient’s head in use may make it easier or more comfortable for a patient to lie or sleep in one or more of the following positions: in a side or l position; in a supine position (i.e. on their back, facing generally upwards); and in a prone position (i.e. on their front, facing generally rds). Moreover, connecting a conduit to the front of a patient interface may exacerbate a problem known as tube drag, wherein the conduit may provide an undesired drag force upon the patient interface thereby causing dislodgement away from the face.

In the form of the present technology illustrated in Figs. 8A-9C and 12AF , the positioning and stabilising structure 3300 ses two tubes 3350, each tube 3350 being positioned in use on a different side of the patient’s head and extending across the respective cheek region, above the tive ear (superior to the otobasion superior on the patient’s head) to the elbow 3610 on top of the head of the patient 1000. This form of technology may be advantageous because, if a patient sleeps with their head on its side and one of the tubes is compressed to block or partially block the flow of gas along the tube, the other tube remains open to supply pressurised gas to the patient. In other examples of the technology, the patient interface 3000 may se a different number of tubes, for example one tube, or three or more tubes. In one example in which the patient interface has one tube 3350, the single tube 3350 is positioned on one side of the patient’s head in use (e.g. across one cheek region) and a strap forms part of the positioning and stabilising structure 3300 and is positioned on the other side of the patient’s head in use (e.g. across the other region) to assist in ng the patient interface 3000 on the patient’s head.

In the form of the technology shown in Figs. 8A-9C and 12A-F the two tubes 3350 are y connected at their upper ends to each other and to connection port 3600. In one embodiment, the two tubes are ally formed while in other embodiments the tubes are separate components that are connected together in use and may be disconnected, for example for cleaning or storage. Where te tubes are used they may be indirectly connected together, for example each may be connected to a T-shaped conduit having two conduit arms each fluidly connectable to the tubes 3350 and a third conduit arm or opening acting as the connection port 3600 P1415NZ7 / 506176NZDIV6 and connectable in use to the air circuit 4170. The connection port 3600 may comprise an elbow 3610 received in fluid connection opening 3390 at the centre of two integrally formed tubes 3350. The elbow 3610 may be received in a ring in the fluid connection opening 3390 and may be configured to swivel within the ring. The fluid tion opening 3390 may be also considered a tion port 3600 .

The tubes 3350 may be formed of a semi-rigid material such as an elastomeric al, e.g. silicone. For example, the tubes 3350, from the left-side non-extendable tube section 3363 to the right side non-extendable tube section 3363, may be formed (e.g., by molding) from a single neous piece of al, such as silicone, as can be seen in Fig. 10A. The tubes may have a natural, preformed shape and be able to be bent or moved into another shape if a force is applied to the tubes. For example, the tubes may be generally arcuate or curved in a shape approximating the contours of a patient’s head between the top of the head and the nasal or oral .

The positioning and stabilising structure 3300 in some es may comprise sleeves 3364 around the tubes 3350. For example, as shown in Figs. 8A to 8D, sleeves 3364 are provided to the non-extendable tube sections 3363. In some examples, the patient interface 3000 may not comprise sleeves 3364 and in other examples the patient interface 3000 may comprise sleeves 3364 that cover more, or all, of the tubes 3350. The sleeves 3364 may be formed to fit to the curved shape of the tubes 3350. In some examples, the sleeves 3364 are formed from a smooth fabric.

The sleeves 3364 may be more comfortable against the patient’s face than the tube 3350 without any covering.

As described in US Patent no. 6,044,844, the contents of which are orated herein, the tubes 3350 may be crush resistant to avoid the flow of breathable gas through the tubes if either is crushed during use, for example if it is squashed between a patient’s face and pillow. Crush resistant tubes may not be necessary in all cases as the pressurised gas in the tubes may act as a splint to prevent or at least restrict crushing of the tubes 3350 during use. A crush resistant tube may be ageous where only a single tube 3350 is present as if the single tube becomes blocked during use the flow of gas would be restricted and therapy will stop or reduce in efficacy.

P1415NZ7 / 506176NZDIV6 In certain forms of the technology, one or more portions of the tubes 3350 may be rigidised by one or more rigidising or stiffening elements. Examples of rigidising elements include: sections of the tubes 3350 that are atively thicker than other sections; sections of the tubes 3350 that are formed from a material that is comparatively more rigid that the material g other sections; and a rigid member attached to the inside, outside or embedded in a section of tube. The use of such sing elements helps to control how the positioning and stabilising structure 3300 will function in use, for example where the tubes 3350 is more likely to deform if forces are applied to them and where the shape of the tubes 3350 is more likely to be maintained if forces are applied. The selection of where such rigidising elements are positioned in the tubes 3350 can therefore help to promote comfort when the patient interface 3000 is worn and can help to maintain a good seal at the seal-forming structure 3100 during use. Rigidising or stiffening elements may be in positioning and stabilising structures 3300 which are configured to t relatively heavy sealforming structures such as full face or oro-nasal n assemblies.

The tubes 3350 in the form of the technology shown in Figs. 8A-9C and 12A-F have a length of between 15 and 30cm each, for example between 20 and 27cm each. In one e each of the tubes are around 26cm long. In another e each of the tubes is around 23cm long. The length of the tubes is selected to be appropriate for the dimensions of the heads of typical patients, for example the distance between the region proximate the top of the head where the upper end of the tubes 3350 are situated, and the region proximate the openings to the patient’s airways at which the lower end of the tubes 3350 connect to the cradle cushion module 3150 (or pillows cushion module 3160) when following a generally arcuate path down the sides of the heads and across the patient’s cheek region such as is shown in Figs. 8A- 9C or 12A-F. As described in more detail below, the patient interface 3000 is configured so that the length of the tubes 3350 can be varied in some forms of the technology and the above s may apply to the tube in a contracted, stretched or l state. It will be appreciated that the length of the tubes 3350 will depend on the length of other components in the patient interface 3000, for example the length of arms of a T-shaped conduit to which the upper ends of tubes 3350 t and/or the size of the plenum chamber 3200.

P1415NZ7 / 506176NZDIV6 .3.2.1.1 Positioning of Headgear ents Each tube 3350 may be configured to receive a flow of air from the tion port 3600 on top of the patient’s head and to deliver the flow of air to the seal-forming structure at the ce of the patient’s airways. In the example of Figs. 8A-9C and 12A-F, the at least one tube 3350 extends between the seal-forming structure 3100 and the connection port 3600 across the patient’s cheek region and above the patient’s ear, i.e. a portion of tube 3350 that connects to the n module overlays a maxilla region of the patient’s head in use and a portion of tube 3350 overlays a region of the patient’s head superior to the otobasion superior on the patient’s head. Each of the one or more tubes 3350 may also lie over the patient’s sphenoid bone and/or temporal bone and either or both of the patient’s l bone and parietal bone. The connection port 3600 and elbow 3610 may be located in use over the patient’s parietal bone, frontal bone or the junction therebetween.

The ary form of the technology illustrated in Figs. 8A-9C and 12A-F has tubes 3350 which curve around the upper part of the patient’s head from the upper end of the tubes 3350 that t to elbow 3610 on top of the head to the point at which the strap 3310 connects to the tubes 3350 with relatively little curvature in the al plane. In between the point at which the rear headgear strap 3310 connects to the tubes 3350 and the lower ends of the tubes 3350 at which they connect with the cradle cushion module 3150 in front of the patient’s s under the nose, the tubes 3350 curve forwards between the patient’s ears and eyes and across the cheek region. The radius of curvature of this section of the tubes 3350 may be in the range 60-100mm, for example 70-90mm, for example 80mm. The lower end of the tubes 3350 and the section of the tubes 3350 at which the rear headgear strap 3310 connects to the tubes 3350 may subtend an angle in the range 65-90°, for example 75-80°. The actual curvature present in the portions of the tubes 3350 superior to the strap 3310, and the actual ure in the portions of the tubes 3350 inferior to the strap 3310, depends on patient setup and in practice will vary depending on the shape and size of the patient’s head and the patient’s preferences.

The degree to which the patient interface 3000 fits an individual patient can be d by varying the length of the tubes 3350 and, alternatively or additionally, by altering the position of the patient interface 3000 or portions thereof P1415NZ7 / 506176NZDIV6 on the patient’s head. For example, a patient interface 3000 having tubes 3350 of a certain length can be ed to better fit a patient by moving portions of the positioning and stabilising structure 3300 in the posterior or anterior direction on the patient’s head. For example, positioning the junction of the tubes 3350 above the patient’s head r forward (i.e. in the anterior direction) enables a patient interface 3000 having tubes 3350 of a certain length to fit a larger head than if the junction of the tubes 3350 is positioned further rd (i.e. in the posterior direction). In most patient, if the junction of the tubes 3350 is positioned forwardly, the superior portions of the tubes 3350 lie over a r portion of the patient’s head than if the junction of the tube 3350 is positioned rearwardly.

In certain forms of the present technology the patient interface 3000 is configured such that the connection port 3600 can be positioned in a range of positions across the top of the patient’s head so that the patient interface 3000 can be oned as appropriate for the comfort or fit of an individual t. One way this can be achieved so that the seal-forming structure 3100 forms an effective seal with the patient’s face irrespective of the position of the connection port 3600 on the t’s head is to de-couple movement of the upper portion of the patient interface 3000 from the lower portion of the t interface 3000. Such de-coupling can be achieved using, for example, mechanisms that allow parts of the headgear tubes 3350 to easily move or flex relative to other parts of the patient interface 3000. Such mechanisms will be described below.

In a certain form of the present logy, the patient interface 3000 is configured such that the connection port 3600 is oned approximately at a top point of the patient’s head. The connection port 3600 may be positioned in the sagittal plane and aligned with the ion superior points in a plane parallel to the coronal plane. The otobasion or points are identified in Fig. 2D. As will be described below, in some forms of the logy, the positioning and ising structure 3300 is configured to be worn in different positions, with the effect that the connection port 3600 may be positioned proximate the top of the patient’s head in the sagittal plane up to around 20mm forward or 20mm rearward of the otobasion superior points.

In some examples of the present technology, the connection port 3600 may be positioned in the sagittal plane and aligned with a junction between the frontal P1415NZ7 / 506176NZDIV6 bone and the parietal bones. The connection port 3600 may be positioned approximately over the junction of the coronal suture and the sagittal suture. In this configuration, the superior portions of the tubes 3350 may lie over and/or along a portion of the coronal suture. r, as mentioned above the patient has the y to move the connection port 3600 anteriorly or posteriorly in order to adjust the fit of the patient ace 3000.

An advantage provided by the tubes 3350 overlying the patient’s head slightly anterior to the superior-most point (e.g. at or proximate the coronal suture) is that the risk of the tubes 3350 riding in a posterior direction in use may be reduced. In many patients there may be a recess or “divot” where the coronal suture meets the sagittal suture. The positioning and stabilising structure 3300 may be particularly stable when tubes 3350 lie within this divot. Accordingly, in some examples the tubes 3350 are configured with appropriate curvature and/or ability to curve in order to lie over the coronal .

As described above, in some examples of the present technology the patient interface 3000 comprises a seal-forming ure 3100 in the form of a cradle cushion which lies generally under the nose and seals to an inferior periphery of the nose. The positioning and stabilising structure 3300 may be ured and arranged to pull the seal-forming structure 3100 into the t’s face under the nose with a sealing force vector that has a posterior and superior direction (e.g. a posterosuperior direction). A g force vector with a posterosuperior direction may facilitate the orming structure 3100 forming a good seal to both the inferior periphery of the patient’s nose and the anterior-facing surfaces of the patient’s face on either side of the patient’s nose and the upper lip.

In some examples, the positioning and stabilising ure 3300 may in use apply a sealing force vector having a osuperior direction at an angle of approximately 35° with respect to the patient’s Frankfort horizontal. The superior portions of the tubes 3350 (e.g. the portions of the tubes 3350 superior to the strap 3310) may be oriented vertically, and the rear headgear strap 3310 may extend from the tubes 3350 in a posteroinferior direction at an angle of approximately 35° with respect to the t’s Frankfort horizontal. In this particular setup, there is an angle P1415NZ7 / 506176NZDIV6 of 125° formed n the strap 3310 and the superior portions of the tubes 3350 where the strap 3310 connects to the tubes 3350.

Fig. 8D shows a side view of a patient wearing the patient interface 3000.

Certain forces acting on a point 3308 above each of the patient’s ears proximate where the strap 3310 connects to the tubes 3350 are identified in Fig. 8D. The superior portions of the tubes 3350 may apply a force 3301 on the point 3308 resulting from headgear tension. The force 3301 may have a substantially vertical direction. The inferior portions of the tubes 3350 (e.g., between the seal-forming structure 3100 and the connection to the rear headgear strap 3310) may apply a force 3303 on this point 3308 in an anterior or direction at an angle of approximately 125° to the vertical force 3301 applied by the superior portions of the tubes 3350. The force 3303 may be equal in ude and opposite in direction to the sealing force at which the seal-forming structure 3100 is pulled into the patient’s face under the nose.

To balance the forces, the strap 3310 applies a force 3302 in a posteroinferior direction at an angle of approximately 125° to the vertical force 3301 applied by the superior portions of the tubes 3350. Accordingly, there is an angle of approximately 110° between the anteroinferior force 3303 applied to the point 3308 along each tube 3350 above the t’s ear and the posteroinferior force 3302 applied by the strap 3310.

A sealing force vector of 35° may be considered optimal for many ts when the positioning and stabilising structure 3300 is used with a cradle cushion. Additionally, the directions of the forces described above applied by each n of the positioning and stabilising structure 3300 may be considered ideal.

However, it will be appreciated that that, in ce, the actual directions of the forces applied by each n of the headgear will vary to accommodate the particular anatomy and preferences of each patient.

For example, in many examples the positioning and stabilising structure 3300 may be ured such that the superior portions of the tubes 3350 lie across the patient’s head slightly anterior to a superior-most point. For some patients this may result in the tubes 3350 being angled slightly anteriorly rather than aligned vertically (e.g. in the coronal plane) in order to lie within a slight recess at or proximate the coronal suture of the skull. In such an e, the tension in the strap P1415NZ7 / 506176NZDIV6 3310 could be ed by the patient to balance the forces and e the l sealing force vector.

In some examples, the positioning and stabilising structure 3300 may be configured to apply a force on the seal-forming structure 3100 in a posterosuperior direction at an angle that bisects an angle formed n the upper lip and the columella (e.g. the surfaces forming the nasolabial angle).

In certain examples of the present technology, the tubes 3350 are configured to receive the strap 3310 at the locations or to and proximate the patient’s ears. If the strap 3310 connects to the tubes 3350 to high with respect to the patient’s head, the strap 3310 may have a tendency to ride up the back of the patient’s head. Additionally, the strap 3310 could form too large of an angle with respect to the superior portions of the headgear tubes 3350, ing in the necessity for the patient to tighten the strap 3310 excessively, which could result in both excessive tension in the positioning and stabilising ure 3300 and make the strap 3310 more likely to ride up the back of the patient’s head. Accordingly, it is advantageous for the connection between the strap 3310 and the tubes 3350 to be provided as low as le but spaced from the top of the patient’s ear sufficiently that upon tightening of the strap 3310, the tubes 3350 are not pulled into contact with the patient’s ears. .3.2.1.2 Headgear Tube Fluid Connections The two tubes 3350 are fluidly connected at their inferior ends to the plenum chamber 3200. In the examples of Figs. 8A-9C and 12A-F, the tubes 3350 form a fluid connection with the cradle cushion module 3150 and seal-forming structure 3100. In certain forms of the technology, the connection between the tubes 3350 and the cradle cushion module 3150 is achieved by connection of two rigid components so that the patient can easily connect the two components together in a reliable manner. The e feedback of a ‘re-assuring click’ or like sound may be easy for a patient to use or for a patient to know that the tube has been correctly connected to the cradle cushion module 3150. In one form, the tubes 3350 are formed from silicone and the lower end of each of the ne tubes 3350 is overmolded to a rigid tor made, for example, from polypropylene, polycarbonate, nylon or the like. The rigid connector may comprise a male mating feature configured to connect to a female mating feature on the cradle cushion module 3150. Alternatively, the rigid P1415NZ7 / 506176NZDIV6 tor may comprise a female mating feature configured to connect to a male mating feature on the cradle cushion module 3150. The same manner of connection by which the tubes 3350 are connected to the cradle cushion module 3150 may also be applied to the tion between the tubes 3350 and the nasal cushion module 3150, or another plenum chamber 3200 or seal-forming structure 3100.

In another embodiment a compression seal is used to connect each tube 3350 to the cradle cushion module 3150. For example, a resiliently flexible (e.g. silicone) tube 3350 without the rigid connector may need to be squeezed ly to reduce its er so that it can be jammed into a port in the plenum chamber 3200 and the inherent ence of the ne pushes the tube 3350 outwards to seal the tube 3350 in the port in an air-tight manner. In a hard-to-hard type engagement between the tube 3350 and port, a pressure activated seal such as a peripheral g flange may be used. When pressurised gas is supplied through the tubes 3350 the sealing flange is urged against the join between the tubes and the inner circumferential surface of the port of the plenum chamber 3200 to enhance the seal n them. If the port is soft and a rigid connector is provided to the tube 3350, the pressure ted seal as described earlier may also be used to ensure the connection is air-tight. In another example, each tube 3350 is formed from a resiliently flexible (e.g. silicone) material which is over moulded to a rigid connector such that the resiliently flexible material fits over the rigid connector and itself functions as a gasket to seal the connection between the tube 3350 and the cradle cushion module 3150 around a periphery of an air flow passage from the tube 3350 into the plenum chamber 3200 of the cradle cushion module 3150.

Similar connection mechanisms may be used to fluidly connect the tubes 3350 with a T-shaped top member defining the connection port 3600 or connectable to the connection port 3600 in some forms of the technology. In one embodiment, a swivel elbow connected at the connection port 3600 is rotatable in order to drive a port size adjustment mechanism that decreases or ses the size of the ports into which tubes 3350 are inserted in order to improve the fit of the tubes through an increase or decrease of ssive forces and to reduce unintended leakage.

Z7 / 506176NZDIV6 1.3 Extendable concertina structure The patient interface 3000 may comprise one or more extendable tube sections. In some examples, an extendable tube section comprises an extendable concertina structure 3362. The patient interface 3000 may comprise a positioning and stabilising structure 3300 including at least one gas delivery tube comprising a tube wall 3352 having an extendable concertina structure 3362. For example, the patient ace 3000 shown in Figs. 8A-9C and 12A-F comprises tubes 3350, the superior portions of which comprise extendable tube sections each in the form of an extendable concertina structure 3362.

Each extendable concertina structure 3362 may comprise a portion of the tube 3350 having one or more folding portions, pleats, corrugations or bellows to form an extendable portion of the tube 3350. In the example shown in Figs. 8A-9C, the extendable concertina structures 3362 each take the form of an extendable concertina structure. The able concertina structures 3362 are separated by the elbow 3610 and connection port 3600. The extendable tina structures 3362 are able to change in length. In particular, each extendable concertina structure 3362 is able to extend or contract in order to change the length of the respective tube 3350.

In some examples, each gas delivery tube 3350 at the extendable tina structure 3362 may comprise a cross-section having a width and a height, where the width is larger than the height and is aligned in use substantially with the anterior-posterior directions. For example, the t interface 3000 illustrated in Figs. 8A-8C comprises extendable concertina structures 3362 each having a crosssectional width greater than a cross-sectional height, the width being the dimension aligned with the anterior and posterior directions of the rated patient 1000. In this example, the width is about twice as large as the height. That said, in this example the width reduces along the length of the able concertina structure 3362. At a superior, or medial, end of each able concertina structure 3362, the width of the tube wall forming the able concertina structure 3362 is relatively larger and is a similar size to a ring in which the swivel elbow 3610 is received in the tube 3350. At an inferior, or lateral, end of each extendable concertina ure 3362, the width of the tube wall is relatively smaller and is a similar size to the width of the nonextendable tube section 3363. An extendable concertina structure 3362 that changes in Z7 / 506176NZDIV6 width between the larger tube size of the connection to the elbow 3610 and the smaller tube size of the non-extendable tube sections 3363 may provide for a sleek and contiguous tube 3350 that may be more comfortable and/or aesthetically appealing (which may improve patient compliance with therapy). .3.2.1.3.1 Bendability In some examples of the present technology, portions of the positioning and stabilising structure 3300 are configured to be more resistant to g in or about some directions or axes than in or about others.

For example, a superior portion of each tube 3350 of the positioning and stabilising structure 3300 shown in Figs. 8A-9C may be more bendable in a particular direction in comparison to an orthogonal direction. Each gas delivery tube 3350 of the oning and stabilising structure 3300 may comprise a or tube portion 3304 configured to overlie a superior region of the patient’s head in use (as illustrated in Figs. 8A-C). In the illustrated example, the superior tube portion 3304 includes the extendable concertina structure 3362. In other examples of the present technology, the superior tube portion 3304 may comprise an alternative extendable tube structure (such as one of the options disclosed in PCT Patent Publication No. WO 2017/124155, the entire ts of which are orated herein by reference) or may be non-extendable.

The superior tube portion 3304 comprises a first end 3305 and a second end 3306. In this e the first end 3305 is configured to overlie or lie against a superior portion of the patient’s head, at imately sagittal plane of the t’s head (e.g. approximately top and centre of the patient’s head). The second end 3306 is configured to overlie the patient’s head laterally from the first end 3305 (e.g. closer to the side of the patient’s head). In some examples, if the superior tube portion 3304 is not particularly long, the second end 3306 may lie laterally with t to the first end 3305 but may not lie particularly inferior to the first end 3305. In other examples, if the superior tube portion 3304 is longer, the second end 3306 may lie both laterally and inferiorly to the first end 3305. Fig. 13 shows a portion of another example of a positioning and stabilising ure 3300. The positioning and stabilising structures of Figs. 8A-9C and also Fig. 13 are able to bend about le axes. For example, the positioning and stabilising structure 3300 in Fig. 13 is able to drape down over the P1415NZ7 / 506176NZDIV6 patient’s head and also curve in the anterior and posterior directions. As illustrated in Fig. 13, the superior tube portion 3304 is bent about two axes.

The superior tube portion 3304 may also comprise one or more stiffened portions between the first end 3305 and the second end 3306. The stiffened portion(s) may be configured to provide a higher resistance to relative movement between the first end 3305 and a second end 3306 in an anterior and/or posterior direction than in a superior and/or inferior direction.

When the patient dons the positioning and stabilising structure 3300, the superior tube portion 3304 may have a relatively low ance to bending in the vertical directions such that the second end 3306 is able to move inferiorly with respect to the first end 3305. This advantageously enables the superior tube n 3304 to “drape” downwardly over the top of the patient’s head to the side of the patient’s head. A relatively high degree of bendability and the superior/inferior directions may be advantageous in enabling the or tube portion 3304 to conform to the curvature of the patient’s head.

Additionally, the superior tube portion 3304 may have a relatively higher resistance to bending in the ntal directions such that the first end 3305 does not unintentionally move anteriorly and/or posteriorly with respect to the second end 3306. This advantageously enables the superior tube portion 3304 to remain in a d position across the top of the patient’s head. With a lower resistance to bending towards the anterior and/or posterior directions, the superior tube portion 3304, and in ular the connection port 3600, may be less likely to ride d or rd along the top of the patient’s head in use. This resistance to a forward or backward movement of the or tube n 3304 is particularly advantageous for the patient interface 3000 given the connection to the air circuit 4170 is provided atop the patient’s head, meaning tube drag forces may act directly on the superior tube portion 3304.

In some examples, the or tube n 3304 may comprise a shape which inherently provides the advantageous resistance to bending. For example, the superior tube portion 3304 may comprise a rectangular cross-section one of the parallel long sides configured to lie t the surfaces of the patient’s head. The Z7 / 506176NZDIV6 long sides of the gular cross section provide a relatively large ance to bending of the superior tube portion in directions parallel to the long sides (e.g. the anterior and/or posterior directions in use). However, the short sides of the rectangular cross section may not e such a large ance to g of the superior tube portion 3304 and directions parallel to the short sides (e.g. the inferior and/or superior directions in use). It will be appreciated that the cross-section of the superior tube portion 3304 may not be perfectly rectangular. For example, the corners and/or short sides may be rounded.

The stiffened portion may be formed by one or more rigidising structures formed by or provided to the tube wall of the tube 3350. In the examples shown in Figs. 8A-10J, the stiffened portion is formed by a plurality of ridge connecting portions 3370 that are configured to resist separation of nt ridges formed by folds in the tube wall. In particular, the stiffened portion is formed by a series of ridge connecting ns 3370 along both the anterior side of the superior tube portion 3304 and the posterior side of the superior tube portion 3304. A tube 3350 that comprises stiffened portions on both the anterior and posterior sides of the tube 3350 may advantageously have a higher resistance to bending towards both the or and posterior sides of the tube 3350. However, in some examples a stiffened portion is provided to only one of the anterior or posterior sides of the tube 3350 since, depending on the stiffness, a stiffened portion on one side only may provide a sufficient resistance to bending towards both directions.

In some examples the ned portion of a tube 3350 may be provided to an extendable portion of the superior tube portion 3304. In the example illustrated in Figs. 8A-10J, the extendable portion comprises an extendable concertina structure 3362 formed in a tube wall of the tube 3350, the extendable concertina ure 3362 comprising a plurality of ridges 3372 and a plurality of grooves 3373, as will be bed in more detail below. In this example, the stiffened portion comprises a plurality of ridge connecting portions 3370 formed in the tube wall, each of the plurality of ridge connecting portions 3370 connecting a pair of adjacent ridges 3372.

The stiffening effects of the ridge connecting ns 3370 are described in more detail below.

P1415NZ7 / 506176NZDIV6 In other examples of the present technology, the t interface 3000 may comprise tubes 3350 having stiffened portions formed by structures other than ridge connecting portions. In some examples, portions of the tubes 3350 (e.g. anterior and/or posterior portions) may comprise stiffened portions being stiffened with one or more rigidising elements. The tubes 3350 may be rigidised with one or more rigidising components having a higher stiffness than the tube 3350 embedded within the tube wall. For example, the tube wall may be overmoulded to an elongate bar or rod formed from a material stiffer than the tube wall. In other examples, a stiffened portion of the tube wall may be provided by further features of the geometry of the tube wall. In one example the tube wall may comprise a r material thickness at the anterior and/or posterior sides of the tube 3350. In another example, the tube wall may comprise a reduced groove depth (or ridge height) at stiffened portions of the tubes 3350. .3.2.1.3.2 Ridges and s The extendable concertina ure 3362 forming each able tube section ses a plurality of ridges 3372 and a plurality of s 3373, as shown in Figs. 10D-10J. The ridges 3372 and grooves 3373 are alternatingly formed into the wall of each tube 3350 to form a concertina structure. An alternating series of ridges and grooves will be understood to refer to a series in which a groove is provided between each pair of ridges and a ridge is provided between each pair of grooves (e.g. ridge, groove, ridge, groove and so on).

The alternating ridges 3372 and grooves 3373 may function like folds or bellows able to fold and unfold independently or in concert to shorten or lengthen the extendable concertina structure 3362 and hence the respective tube 3350. A large groove depth (or ridge height) may e for a more extendable tube 3350. When tension is applied to the tubes 3350, the ridges 3372 and grooves 3373 of the extendable concertina ures 3362 may be pulled away from each other which straightens out the tube wall, lengthening the tubes 3350. In this example, the extendable concertina ure 3362 is biased to an original (e.g. unextended) length.

Upon release of ar tension the ridges 3372 and grooves 3373 are biased back to an original uration in which each extendable concertina structure 3362 and the tubes 3350 have original lengths.

P1415NZ7 / 506176NZDIV6 In addition to facilitating a change in the length, the ridges 3372 and grooves 3373 may also facilitate a change in shape of the extendable concertina structure 3362 of each tube 3350. In some examples of the present logy, a first series of alternating ridges 3372 and grooves 3373 is provided to a first side of the tube 3350 in the extendable concertina structure 3362 (e.g. a patient-contacting side), while a second series of ating ridges 3372 and grooves 3373 is provided to a , opposite, side of the tube 3350 (e.g. a non-patient-contacting side). The extendable concertina structure 3362 may facilitate bending of the tube 3350 as the ridges 3372 and grooves 3373 are able to move with respect to each other by differing degrees on the different sides of the tube 3350. For example, on the first side of the tube 3350 the ridges 3372 and grooves 3373 may contract while on the second side of the tube 3350 the ridges 3372 and grooves 3373 may expand, with the result being that the tube 3350 bends in the extendable concertina structure 3362. Alternatively, the ridges 3372 and grooves 3373 on both the first side and the second side may expand, in use, but the ridges 3372 and groove 3373 on the first side may expand less to enable to tube 3350 to bend (e.g. curve) in the direction of the first side, for example to conform or wrap to (e.g. drape over) the patient’s head while extending in length.

In some examples, the first alternating series of ridges 3372 and grooves 3373 may have a lesser extension stiffness (e.g. a lesser force required to e a change in unit length) than the second alternating series of ridges 3372 and grooves 3373. The reduced extension stiffness in the non-patient-contacting side of the extendable concertina structure 3362 may ageously facilitate bending/curvature in the tubes 3350 in use by enabling the rd side of the tube 3350 to extend to cover a greater arc length then the d side of the tubes 3350 in the extendable concertina structure 3362. While the extension stiffness of both the first and the second alternating series of ridges 3372 and s 3373 may differ from one another, the extension stiffnesses of each may be selected to achieve a desired overall extension stiffness of the extendable concertina structure 3362.

The ridges 3372 and grooves 3373 may each be formed along a portion of the tube wall around a ty of a longitudinal axis of the tube 3350, such as on all, or almost all, of the sides of the tube 3350. This may enable the able concertina P1415NZ7 / 506176NZDIV6 structure 3362 to bend about multiple axes. As shown in Figs. 10H-10J and Fig. 13, extendable concertina structures 3362 ing to examples of the present technology may enable the tubes 3350 in multiple axes. Figs. 10H and 10I show an extendable concertina structure 3362 bending in the superior-inferior directions (e.g. to drape over a patient’s head), Fig. 10J shows the extendable concertina structure 3362 g in the anterior-posterior directions (e.g. to enable the tubes 3350 to lie over the top of the patient’s head at different ons) and Fig. 13 shows an extendable concertina structure 10J bending in both the superior-inferior and anteriorposterior directions at the same time.

In some examples, each of the ridges 3372 and grooves 3373 are substantially straight. In other examples, the ridges 3372 and/or grooves 3373 may comprise one or more arcuate portions.

As shown in Figure 10D, each ridge 3372 comprises a central curved ridge portion 3374. That is, each ridge 3372 comprises an accurate n in the centre thereof. However, at the ends of each ridge 3372 are straight ridge portions 3375. Accordingly, each of the ridges 3372 comprises a pair of straight ridge ns 3375 provided at opposite ends of the ridge 3372.

Similarly, each groove 3373 comprises a curved groove portion 3376 l the tive groove. The centre of each groove 3373 is therefore accurate.

Additionally, at the end of each groove 3373 is a straight groove portion 3377. Each of the grooves 3373 comprises a pair of straight groove portions 3377 ed at te ends of the groove 3373. Each of the curved groove portions 3376 may comprise curvature ng or defined by the curvature of the pair of adjacent ridges 3372, in particular the curvature of the curved ridge portions 3374.

Each of the ridge connecting portions 3370 connects a respective adjacent pair of ridges 3372 at the straight ridge portions 3375 of the pair of ridges 3372. The ht groove portions 3377 may each be defined between adjacent straight ridge portions 3375 on either side along the length of the tube 3350 and a ridge connecting portion 3370 either superior or inferior to the straight groove portion 3377 (as the case may be for each straight groove portion 3377, depending on whether it is on a superior or inferior side of the tube 3350).

P1415NZ7 / 506176NZDIV6 While the extendable concertina structure 3362 comprises ridges 3372 and grooves 3373 on an exterior of the gas delivery tube 3350, the folds forming the extendable tina structure 3362 may also form ridges and grooves interior to the gas delivery tube 3350 (e.g. as a result of the folds forming a wavelike shape in the tube wall, such as a sinusoidal shape, square wave or other waveform). Fig. 10B shows the particular wavelike shape formed in the tube walls. As shown in Fig 10B, the able concertina structure 3362 comprises folds g interior ridges 3382 and interior grooves 3383. In particular, the folds in the tube wall form, interior to the tubes 3350, a first alternating series of interior ridges 3382a and interior grooves 3383a along the non-patient-contacting side of the tube 3350. Additionally, the folds form a second alternating series of interior ridges 3382b and interior grooves 3383b along the patient-contacting side of the tubes 3350.

Each interior groove 3383a of the first alternating series may be provided opposite a respective interior groove 3383b of the second ating series across the interior of the tube 3350 to form a plurality of opposing groove pairs. That is, each interior groove 3383a on the non-patient-contacting side of the tube 3350 may be paired with an ng interior groove 3383b on the patient-contacting side. As illustrated in Fig. 10B, each ng groove pair comprises a first interior groove 3383a and a second interior groove 3383b. In this example, the first interior groove 3383a comprises a greater groove depth than the second interior groove 3383b. The greater groove depth of the first interior groove 3383a in each opposing groove pair results in the first alternating series of ridges and grooves having a lower extension stiffness than the second alternating . In other examples of the t technology, the relatively lower stiffness of the ridges and grooves forming the first alternating series may be provided by stiffening the second alternating series of ridges and grooves. In one example, ridge connecting ns 3370 (described tely below) are provided to the tube wall to connect pairs of adjacent ridges. In another example, the second alternating series of ridges and grooves are formed by a stiffer material than the first alternating series (e.g. a different material having a higher ess or, in the case of the tube being formed from silicone, a region of silicone having a higher Durometer, etc.). In a further example, the second alternating series of ridges and grooves may be stiffened with a rigidising component.

P1415NZ7 / 506176NZDIV6 In the illustrated example, the tube wall of the tube 3350 comprises a greater material thickness at a base of the second interior groove 3383b of each opposing groove pair than at a base of the first interior groove 3383a of the respective groove pair. The greater material thickness forming the basis of the second interior groove 3383b of each of those in groove pair reduces the groove depth of the second interior groove 3383b. The reduced groove depth reduces the ibility of the extendable concertina structure 3362 on the side having the second alternating series of ridges and grooves.

As shown in Fig. 10B, the material thickness of the tube wall at the base of each interior groove 3383b of the second alternating series reduces along the length of the tube 3350 from the first end proximate the connection port 3600 to a second end. Additionally, the material thickness of the tube wall at the base of each interior groove 3383a of the first alternating series is substantially nt along the length of the tube 3350. The groove depth of the interior grooves 3383a and 3383b of the first and second alternating series of interior ridges 3382 and interior grooves 3383 reduces along the length of the gas ry tube 3350 from the first end nt the tion port 3600 to the second end. The reduction in groove depth on both sides of the tube 3350 along the length of the extendable concertina structure 3362 facilitate a change in size of the tube 3350 n the larger connection port 3600 and the r non-extendable tube section 3363. While the groove depth is generally lesser at the second end in ison to the first end, for each opposing groove pair, the second interior groove 3383b on the second, patient-contacting side, of the extendable concertina structure 3362 has a lesser groove depth then the opposing first interior groove 3383a on the first, non-patient-contacting side.

In this example, the first interior groove 3383a of each opposed groove pair is joined to the second interior groove 3383b of the respective opposed groove pair at sides of the tube 3350 between the non-patient-contacting side and the patientcontacting side. That is, tube 3350 is grooved all of the way around the interior of the tube wall. The first interior groove 3383a and second interior groove 3383b of each opposed groove pair are therefore contiguous. Similarly, each interior ridge 3382a of the first alternating series of interior ridges 3382a and interior grooves 3383a P1415NZ7 / 506176NZDIV6 uous with an opposing interior ridge 3382b of the second alternating series interior ridges 3382b and interior grooves 3383b. .3.2.1.3.3 Ridge Connecting Portions As shown in Figs. J, the able tina structures 3362 also comprise a plurality of ridge connecting portions 3370 ed to the tube wall of the gas delivery tube 3350. Each of the ridge connecting portions 3370 connects a pair of adjacent ridges 3372. The ridge connection portions 3370 may each comprise an integrally formed portion of the tube wall. Each ridge connection portion 3370 may be formed into the tube wall. Each ridge connection portion 3370 connects two or more adjacent ridges 3372 and is configured to resist separation of the ridges 3372. The ridge connection portions 3370 may not prevent separation of the ridges 3372 but may increase the stiffness of the extendable concertina structure 3362.

One function of the ridge ting portions 3370 is to reduce the ability of the extendable concertina structures 3362 to extend. While the extendable concertina structures 3362 are intended to extend, and there are be advantages associated with tubes 3350 that are extendable in length, an excessively extendable tube 3350 may be difficult for a patient to use comfortably and securely. The ridge connecting portions 3370 therefore temper the ability of the extendable concertina structure 3362 to increase in length but do not prevent it from extending at all. In the illustrated example, the ridge connecting portions 3370 in combination with the ridges 3372 and grooves 3373 form extendable concertina structures 3362 that facilitate sufficient extension to the lengths of the tubes 3350 to improve the ability of the positioning and stabilising structure 3300 to fit to a range of t head sizes without being so flexible that sufficient tension and g force cannot be achieved.

Each pair of adjacent ridges 3372 of an extendable concertina structure 3362 may be connected by at least one ridge connecting n 3370. Alternatively, or additionally, one or more pairs of adjacent ridges 3372 may be connected by two ridge connecting ns 3370. As shown in Figs. 10D-10J, each pair of adjacent ridges 3372 of the able concertina structure 3362 is ted by two ridge connecting portions 3370. Each of the ridge connecting portions 3370 may be spaced centrally between an inferior side of the gas delivery tube 3350 (e.g. a patient P1415NZ7 / NZDIV6 contacting side) and a or side of the gas delivery tube 3350 (e.g. an upwardly and/or outwardly facing side).

Another function of the ridge connecting portions 3370 is that they provide sed stiffening to the extendable concertina structures 3362. Localised stiffening provided to the extendable concertina structure 3362 may be advantageous for headgear tubes 3350 that are intended to easily bend about one axis while having a particular resistance to bending about a different axis.

In some examples, ridge connecting portions 3370 are provided between ridges 3372 and grooves 3373 on sides of the tube 3350 configured to bend less than other sides of the tube 3350. One or more ridge connecting ns 3370 may be located on an anterior-facing side of the gas delivery tube 3350. Alternatively, or additionally, one or more ridge connecting portions 3370 may be located on a posterior-facing side of the gas delivery tube 3350.

In the illustrated example, as shown in Figs. 10D-10J, ridge connecting portions 3370 are provided to the positioning and stabilising structure 3300 between ridges 3372 on the or and posterior sides of the able concertina structures 3362. That is, each pair of adjacent ridges 3372 is connected by a ridge connecting portion 3370 d on the anterior-facing side of the gas delivery tube 3350.

Additionally, each pair of adjacent ridges 3372 is connected by a ridge connecting portion 3370 located on the ior-facing side of the gas delivery tube 3350.

Since the ridge connecting portions 3370 are located on the anterior and posterior sides in this example, the ridge ting portions 3370 provide greater resistance to the extendable concertina structures 3362 bending towards the anterior and posterior directions than towards the superior and inferior directions. This is advantageous since the extendable concertina structures 3362 maintain the ability to bend to fit to the superior and lateral surfaces of the patient’s head. This ability to bend results in the tubes 3350 being able to drape down over the patient’s head and fit comfortably. Meanwhile, the reduced ability of the extendable concertina structure 3362 to bend towards the anterior and posterior ions may reduce the tendency of the or-most portion of the positioning and ising structure 3300 to move or P1415NZ7 / 506176NZDIV6 ride anteriorly or iorly in use, which may compromise stability of the t interface 3000.

The provision of ridge connecting portions 3370 may be advantageous in limiting the extendibility of the extendable concertina structures 3362 without excessively compromising the ability of the extendable concertina ures 3362 to bend about particular axes in which it is advantageous for the extendable tube sections to do so.

Another function provided by the ridge connecting portions 3370 in some es of the present technology is added ance to twisting of the extendable concertina structures 3362. As the connection port 3600 is provided between the extendable concertina structures 3362, tube drag forces in some circumstances could act on the tubes 3350 to induce twisting in the extendable concertina structures 3362.

The low-profile shape of the tubes 3350 (e.g. the approximately rectangular cross section) may provide resistance to twisting, however the ridge connecting portions 3370 advantageously provide further twisting resistance. The ridge connecting portions 3370 may stiffen the or and posterior sides of the extendable concertina structures 3362, functioning as ning portions, to reduce the possibility of the tubes 3350 twisting.

In some examples of the present technology, the grooves 3373 of an extendable concertina structure 3362 may be formed as depressions with respect to outer es of the gas delivery tube 3350. In other examples, the ridges 3372 of the able concertina structure 3362 may be raised with respect to outwardly facing surfaces of the tube wall and the grooves 3373 may be formed by the spaces between the raised ridges 3372. As shown in Figs. 10D-10J, the s 3373 are formed as depressions with respect to outer surfaces of the tube 3350. The outer surfaces of the tube 3350 from which the grooves 3373 recessed may be contiguous with an outer surface of the non-extendable tube section 3363. An advantage of forming the s 3373 as depressions with respect to an outer surface of the tubes 3350 is that the ridges 3372 do not protrude outwardly from beyond the outer surface of the nonextendable tube section 3363. dly protruding ridges may be uncomfortable for the patient.

P1415NZ7 / 506176NZDIV6 Also as shown in Figs. 10D-10J, dly facing surfaces of the ridge ting portions 3370 do not protrude outwardly with respect to a longitudinal axis of the tube further than the ridges 3372. Additionally, each of the ridge connecting portions 3370 comprises an outwardly facing surface contiguous with outwardly facing surfaces of adjacent ridges 3372. It may be less aesthetically ng for the ridge connecting portions 3370 to protrude outwardly with t to the longitudinal axis of the tube 3350 further than the ridges 3372, although they may do so in some examples of the present logy, for example to provide increased bending and/or twisting resistance.

Furthermore, as shown in Figs 10D-10J, each of the plurality of grooves 3373 is located between a respective pair of ridge connecting portions 3370. Each respective ridge connecting portion 3370 is located at a respective end of a respective groove 3373. onally, each of the plurality of grooves 3373 comprises a groove depth and each of the plurality of ridge connecting portions 3370 comprises a ridge connecting portion height. For each respective set of ridge ting portions 3370 and grooves 3373, the groove depth is equal to the ridge connecting portion height.

That is, the groove depth of each groove 3373 is equal to the ridge tion portion height of each ridge connecting portion 3370 of the respective pair of ridge connecting portions 3370 d at the end of the respective groove 3373.

Accordingly, the grooves 3373 are formed as depressions with respect to outer es of the ridge connection portions 3370, ridges 3372 and tube wall of the tube 3350.

The ridge connection portions 3370 may be relatively narrow and rib-like, as shown in the illustrated example. Alternatively, the ridge connection portions 3370 may be thicker (e.g. such that they occupy a larger portion of the anterior and posterior sides of the extendable portions of the tubes 3350).

In the illustrated examples, the ridge connecting portions 3370 are provided on an exterior side of the tubes 3350. That is, the ridge connecting portions 3370 connect ridges 3372 on the outside of the tube wall, rather than on the inside which defines the hollow or within the tubes 3350. In other examples, the ridge ting portions 3370 may be provided to an interior side of the tube wall of the tubes 3350. The folds in the tube wall forming the extendable concertina structure P1415NZ7 / 506176NZDIV6 3362 may form, on an interior side of the tube wall, a series of alternating ridges and s inverse to the series of ridges 3372 and grooves 3373 formed on the exterior side of the tube wall. That is, the folds g a ridge 3372 on the exterior of the tube wall may form a groove around an interior of the tube wall. Similarly, the folds forming a groove 3373 on the exterior of the tube wall may form a ridge on the interior of the tube wall.

Ridge connecting portions 3370 may connect between adjacent ridges on either the or or the interior of the tube 3350 to resist separation of the ridges. In an example of a oning and stabilising structure 3300 with ridge connecting portions 3370 on the exterior of the tube 3350, the ridges 3372 on the or of the tube are connected and would require greater tension to be separated, while the ridges on the interior of the tube would be more freely separable. Similarly, in an alternatively e of a positioning and stabilising structure 3300 with ridge connecting portions 3370 connecting ridges on the interior of the tube 3350, the ridges on the interior of the tube wall require a r force to be separated, while the ridges on the exterior of the tube are more freely separable. In some es, ridge connection portions 3370 connect a combination of interior and exterior rides.

In some examples of the present technology, a single ridge connection portion 3370 connects multiple ridges 3372. In other examples, each ridge connection portion 3370 connects only a single pair of adjacent ridges 3372. In some examples, one or more ridge connection portions 3370 may connect non-adjacent ridges 3372 (e.g. first and last ridges, every second ridge, etc.). .3.2.1.4 Non-extendable headgear tubing The t interface 3000 may comprise one or more non-extendable tube ns 3363. For example, the patient ace 3000 shown in Figs. 8A-9C comprises tubes 3350, the inferior portions of which comprise non-extendable tube sections 3363. The non-extendable tube sections 3363 are configured to overlie the patient’s cheeks and may be configured to contact the patient’s face inferior to the patient’s cheekbones. Each non-extendable tube section 3363 may lie on a curve extending inferiorly from the connection between the respective headgear tube 3350 and then extending in a partially or and partially medial direction towards the seal-forming structure 3100 in order to avoid the patient’s cheek bones.

P1415NZ7 / 506176NZDIV6 It is advantageous that the positioning and stabilising structure to 3300 of the patient interface 3000 does not lie over the patient’s cheek bones. The regions of a patient’s face inferior to the cheekbones are generally more fleshy and a patient may find it more tolerable for the headgear tubes 3350 to lie over these regions of the face.

Additionally, since the cheek bone regions of the patient’s face are relatively unable to move or deform, the non-extendable tube sections 3363 lie firmly against the fleshy cheek regions. Further, the patient’s cheek bones can assist in preventing the inferior portions of the headgear tubes 3350 from riding up over the cheekbones towards the t’s eyes. When the non-extendable tube ns 3363 fit snugly against the patient’s cheeks below the cheekbones, the ss and ence of the patient’s cheekbones may provide a barrier to the headgear tubes 3350 riding up towards the patient’s eyes (which could affect stability and/or may obscure the patient’s vision).

The cross-sectional shape of the non-extendable tube sections 3363 of the tubes 3350 may be circular, ical, oval, D-shaped or a rounded rectangle, for example as bed in US Patent No. 6,044,844. A cross-sectional shape that presents a ned surface of tube on the side that faces and contacts the patient’s face or other part of the head may be more comfortable to wear than, for example a tube with a circular cross-section.

The cross-sectional width and/or height of the tubes 3350 may be in the range 8-25mm, for example 10-20mm. In some forms in which the tubes have a D- shaped cross-section, for example in the case of the longitudinal section of headgear tubing 3350 shown in Fig. 10C, the tubes have a width in the range 15-25mm, for example 20mm, and a height in the range 8-15mm, for example 10mm. The height may be considered to be the dimension of the tube extending away from the t’s face in use, i.e. the distance between the patient contacting side 3348 and the outermost part of the non-patient contacting side 3349, while the width may be considered to be the dimension across the surface of the t’s head. The cross- sectional thickness of the material forming the tubes 3350 may be in the range 0.8- 1.6mm, for example 1.0-1.5mm, for example 1.3mm.

The D-shaped cross-sectional tube 3350 has rounded edges 3347 flanking the patient ting side 3348. Rounded edges in contact with, or proximate to, the patient’s skin help the patient interface 3000 to be more comfortable to wear and to P1415NZ7 / 506176NZDIV6 avoid leaving marks on, or irritating, the patient’s skin. A tube with a D-shaped crosssectional profile is also more ant to buckling than other shaped profiles.

A further advantage of the D-shaped cross section of the non-extendable tube sections 3363 of the tubes 3350 is that the non-extendable tube sections 3363 that lie in front of the patient’s face in use are more ant to bending in the vertical directions than in the horizontal ions. The D-shaped cross-section makes the non-extendable tube sections 3363 more resistant to bending parallel to the long axis of the D-shape than to bending dicular to the long axis of the D-shape. This is advantageous as the non-extendable tube sections 3363 are more readily able to bend to curve inwardly around the front of the patient’s face to the seal-forming structure 3100, yet retain stiffness and the vertical direction to enable the vertical forces applied on the non-extendable tube section 3363 from the extendable concertina structure 3362 to be transferred to the seal-forming structure 3100 in order to provide the necessary sealing force to the seal-forming structure 3100.

The ability to bend inwardly around the front of the t’s face s the non-extendable tube section 3363 to fit snugly against the t’s cheeks inferior to the t’s cheekbones. As described above in more detail, non-extendable tube sections 3363 that lie snugly under the patient’s cheekbones may provide for a more stable seal than tendable tube sections 3363 that lie loosely over the patient’s cheeks or lie high over the patient’s cheekbones.

In other examples, the non-extendable tube sections 3363 may comprise a rectangular shaped cross-section. A rectangular cross-section may provide similar ages to a D-shaped cross-section. In particular, a rectangular cross-section may provide the non-extendable tube section 3363 with a greater resistance to bending in a direction parallel to the short sides of the rectangular cross section. In other examples, the non-extendable tube sections 3363 may comprise an elliptical or oval-shaped cross-section which would provide similar advantages.

In some examples of the present technology, the non-extendable tube sections 3363 connect to a cradle cushion module 3150 from a low angle. As described above, the headgear tubes 3350 may extend and orly down the sides of the patient’s head and then curve anteriorly and ly to connect to a cradle P1415NZ7 / 506176NZDIV6 cushion module 3150 in front of the patient’s face. The tubes 3350, before ting to the cradle cushion module 3150, may extend to a location at the same al position as or, in some examples, inferior to the connection with the cradle cushion module 3150. That is, the tubes 3350 may project in an at least partially or direction before connecting with the cradle cushion module 3150. A portion of the tubes 3350 may be located inferior to the cradle cushion module 3150 and/or the seal- forming structure 3100. The low position of the tubes 3350 in front of the patient’s face facilitates t with the patient’s face below the patient’s ones. .3.2.2 Headgear Sizing and Stiffness Positioning and stabilising ures 3300 may vary in size between different examples of the present technology. Providing different size options for the patient interface 3000 may enable more patients to be accommodated. A loop around the patient’s head may be formed by the pair of headgear tubes 3350 and the cradle cushion module 3150 (or the pillows cushion module 3160 or other seal-forming structure 3100) connected between the or ends of the tubes 3350. The size of this loop may be varied in order to provide for different size patient interfaces 3000.

In one example, the nded length of the loop formed by the tubes 3350 and the cradle cushion module 3150, measured along the centreline of the patient-facing side of the loop, may be within the range of 510-610 mm. In some examples, the unextended length of this loop may be within the range of 525-600 mm.

In some examples the length of this loop may be within the range of 535-590 mm.

In some particular examples, the unextended length of the loop referred to above may be within the range of 528-548 mm, such as within the range of 535-541 mm, for example about 538 mm. In further particular examples, the length of this loop may be within the range of 534-554 mm, such as within the range of 9 mm, such as about 544 mm or about 547 mm, in examples. In further particular examples, the unextended length of this loop may be within the range of 541-561 mm, such as within the range of 546-556 mm, for e about 551 mm.

In other particular examples, the unextended length of the loop referred to above may be within the range of 564-584 mm, such as within the range of 571-581 mm, such as about 574 or about 579 mm, in examples. In further examples, the Z7 / 506176NZDIV6 unextended length of this loop may be within the range of 577-597 mm, such as within the range of 582-592 mm, such as about 583 mm or about 587 mm, in examples.

The length of the gas delivery tubes 3350, in particular, may be varied in order to provide different sizes of the positioning and stabilising structure 3300. In some examples, the unextended length of the tubes 3350 measured along the centreline of the t-facing side of the tubes 3350 may be within the range of 500- 535 mm, such as between 510-525 mm, such as within the range of 2 mm, for example about 517 mm. In further examples, the unextended length of the tubes 3350 may be within the range of 460-500 mm, such as between 470-490 mm, such as within the range of 475-485 mm, for example about 481 mm.

As described in more detail above, in some examples of the present technology, the headgear tubes 3350 comprise extendable ns (e.g. extendable concertina structures 3362). In some examples of the present technology, the extendable portion of a gas delivery tube 3350 (e.g. a single concertina n on one side of the positioning and stabilising structure 3300) may comprise a stiffness (for extension) within a range of 2-3.5N/10mm (e.g. 0.2-0.35 N/mm). In particular examples, the extendable portion may comprise a stiffness within a range of 2.5- 3N/10mm (e.g. 0.25-0.3 N/mm). In one example, the extendable n may comprise a stiffness of approximately 2.75N/10mm (e.g. 0.275 N/mm). In further examples of the present technology, the extendable portion of a tube 3350 may require between 2.5N and 3N of tension to extend in length by 10mm and may require between 5N and 5.5N of tension to extend in length by 20mm. It will be appreciated that, in various examples of patient interfaces 3000 according to the present technology, any of these disclosed stiffnesses may be provided to tubes 3350 having any of the sizes (e.g. lengths) described above. 3 Headgear straps In certain forms of the t technology, the positioning and stabilising structure 3300 comprises at least one ar strap acting in addition to the tubes 3350 to position and stabilise the seal-forming structure 3100 in g position at the entrance to the patient’s airways. As shown in Figs, 8A-9C, the patient interface 3000 comprises a strap 3310 forming part of the positioning and stabilising structure 3300.

P1415NZ7 / 506176NZDIV6 The strap 3310 may be known as a back strap or a rear headgear strap, for example. In other examples of the present technology, one or more r straps may be provided.

For e, a patient interface 3000 according to an example of the t technology having a full face or oro-nasal n module may have a second, lower, strap configured to overlie the back of the patient’s neck. 3.1 Strap In the example shown in Figs. 8A-9C, strap 3310 of the positioning and stabilising ure 3300 is connected between the two tubes 3350 positioned on each side of the patient’s head and passing around the back of the patient’s head, for example overlying or lying inferior to the occipital bone of the patient’s head in use.

The strap 3310 connects to each tube above the patient’s ears. In other embodiments, for example as part of an oro-nasal patient interface, the positioning and stabilising structure 3300 comprises an upper strap similar to strap 3310 and at least one additional lower headgear strap that connects between the tubes and/or cushion module and passes below the patient’s ears and around the back of the patient’s head.

Such a lower ar strap may also be connected to an upper strap (e.g. a similar to strap 3310).

In certain forms of the technology, the positioning and stabilising ure 3300 comprises a mechanism for connecting a headgear strap to the headgear tubes 3350. The headgear strap may be connected directly or indirectly to the headgear tubes 3350. In the case of the patient interface 3000 shown in Figs. 8A- 9C, for example, a tab 3320 configured to connect to strap 3310 projects outwardly from each headgear tube 3350 in a generally posterior direction. The tabs 3320 have holes in them to receive the ends of strap 3310.

In some forms of the t technology, the strap 3310 is adjustable. For example, in the case of the patient interface shown in Figs. 8A-9C the strap 3310 is, in use, threaded through a hole in the form of an eyelet in each tab 3320. The length of the strap 3310 between the tabs 3320 may be adjusted by pulling more or less of the strap 3310 through one or both of the tabs 3320. The strap 3310 may be secured to itself after passing through the eyelets in the tabs 3320, for e, with ndloop fastening means. The strap 3310 therefore is able to be adjusted to fit around different head sizes. In some forms of the technology the angle of the strap 3310 P1415NZ7 / 506176NZDIV6 relative to the headgear tubes 3350 or patient’s head is able to be adjusted to fit around the patient’s head at different locations. This adjustability assists the positioning and stabilising structure 3300 to accommodate different head shapes and sizes.

In some forms of the technology, the strap 3310 exerts a force on the headgear tubes 3350 to pull them in an at least partially posterior (e.g. rearwards) direction at the locations of the tabs 3320. The strap 3310 may also exert a force on the headgear tubes 3350 to pull them in an at least partially inferior (e.g. downwards) direction. The magnitude of this force may be adjusted by altering the length of the strap 3310 between the tabs 3320.

In some forms of the technology, such as the example shown in Fig. 8A- 9C, the direction of the force applied to the headgear tubes 3350 by the strap 3310 may also be altered. This direction may be altered by adjusting the angle of the strap 3310 relative to the headgear tubes 3350 or patient’s head. In some forms of the technology the location at which the strap 3310 exerts a force on the headgear tubes 3350 may be d by adjusting the location at which the strap 3310 is secured to the headgear tubes 3350.

The adjustability of the magnitude and direction of the force applied to the headgear tubes 3350 by the strap 3310 may advantageously enable the positioning and stabilising structure 3300 to accommodate a range of head sizes and head shapes. The strap 3310 may balance forces in the headgear tubes 3350 which may assist the headgear to in its shape and an effective seal to the patient’s face, while remaining comfortable.

In some forms of the technology, when worn by a patient, a point on the ar tubes 3350 near the tab 3320 will receive a generally upward (e.g. or) force from the upper portion of the headgear tubes 3350 due to n in the headgear tubes 3350 and, in some examples, due to a biasing mechanism ibed in further detail below) acting to keep the headgear secured to the patient’s head.

Additionally, the point on the ar tubes 3350 near the tab 3320 may e a generally forward (e.g. anterior) and downward (e.g. or) force caused by a biasing mechanism acting to urge the seal-forming ure 3100 upwards and into P1415NZ7 / 506176NZDIV6 the patient’s nose. The directions and magnitudes of the forces required for a secure fit and effective seal may vary between ts based on the on of the positioning and stabilising structure 3300 on the head, which may vary due to, for example, differences in head shapes and sizes. In some forms of the technology, the adjustability of the rear headgear strap 3310 enables the forces to be balanced for a range of head shapes and sizes to hold the positioning and stabilising structure 3300 in a comfortable position while maintaining an effective seal.

For example, to provide a larger force acting in the posterior (e.g. rearward) ion on the portions of the headgear tubes 3350 proximate the tabs 3320, the strap 3310 may be adjusted by pulling more of the strap 3310 through the slots in the tabs 3320. Doing so will cause the strap 3310 to shorten in length and, especially if the strap 3310 is c, to apply a larger force on the ar tubes 3350 in the posterior (e.g. rearward) direction. Similarly, the angle of the strap 3310 may be adjusted as required to balance both the vertical and horizontal components of the forces acting on the portions of the headgear tubes 3350 proximate the tabs 3320, across a range of head shapes and sizes.

The strap 3310 may comprise a rectangular cross-section along some or all of its length. Additionally, the strap 3310 may have a profile with one or more d edges to provide greater comfort and to reduce the risk of headgear straps marking or irritating the t. In certain forms of the present technology, a positioning and stabilising structure 3300 comprises a strap 3310 that is le and e.g. non-rigid. An advantage of this aspect is that the strap 3310 is more comfortable for a patient to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning and stabilising structure 3300 comprises a strap 3310 that comprises two or more strap bands separated by a split. For example, as shown in Figs. 8A-9C and 12A-F, the strap 3310 comprises a split 3313 configured in use to be located against the ior of the patient’s head. A split strap 3310 may anchor the patient interface 3000 on the patient’s head in a particularly stable fashion in the case of some t interface designs. The posterior of the patient’s head may have complex geometry and the presence of a split 3313 in the strap 3310 may assist the strap to better conform to the back of the patient’s head.

P1415NZ7 / 506176NZDIV6 .3.2.3.2 Eyelets As noted above, each of the gas delivery tubes may comprise an eyelet for tion with a strap. In some examples, the eyelet may be ar. In other examples, the eyelets may be te. Alternatively, the eyelets may have a round side and a straight side. The eyelets may be D-shaped, for example. The s in the exemplary patient interface 3000 shown in Figs. 8A-9C are in the form of slits 3322.

In this example, the pair of gas delivery tubes 3350 provide a pair of slits 3322 to which a strap 3310 is able to be connected. That is, the strap 3310 may connect between the eyelets. The strap 3310 may be constructed and ed to contact, in use, a region of the t’s head or to or ying an occipital bone of the patient’s head. In this example, the slits 3322 are formed in tabs 3320 connected to the tube walls of the tubes 3350.

In some examples of the present technology, the eyelets may be located on each tube 3350 each between 70mm and 150 mm along the tube 3350 from the centre of the pair of tubes 3350 (e.g. the connection port 3600). In further examples, each eyelet may be located between about 110mm and 130mm along each tube 3350 from the centre of the pair of tubes 3350. In particular examples the eyelets may be located between around 120mm and 125mm along each tube 3350 from the connection port 3600. In the case of the illustrated positioning and stabilising structure 3300, having slits 3322, the midpoints of the slits are located around 120- 125mm from the centre of the pair of gas delivery tubes 3350.

The exemplary patient interface 3000 shown in Figs. 8A-9C includes a single rear headgear strap 3310 passing between the slits 3322 and which will typically need to apply a force on the tubes 3350 in a partially inferior and partially posterior direction. To apply a force on the tubes 3350 in the necessary ion, the strap 3310 should wrap low around the back of the patient’s head. Typically, the back of the patient’s head will generally curve inferiorly and anteriorly over the occipital bone of the skull s where the head joins the patient’s neck.

If the strap 3310 does not lie low enough around the back of the patient’s head (e.g. not inferior to the posterior-most point of the patient’s head, where the posterior surfaces of the patient’s head curve towards the anterior direction and faith partially in an inferior direction) there is a risk that the strap 3310 may ride up the P1415NZ7 / 506176NZDIV6 back of the patient’s head in use. If the strap 3310 rides up superior to the iormost point of the patient’s head, the strap 3310 may lie on a region of the patient’s head that faces in a partially superior direction. If this occurs, it is possible that tension in the strap 3310 could pull the strap up further, which could result in failure of the positioning and stabilising structure 3300 to provide the necessary g force vector to the seal-forming structure 3100 (after which the seal to the patient’s face could be compromised and the patient would need to re-don the patient interface 3000).

As illustrated in Figs. 11A-11C, each of the gas delivery tubes 3350 may se a tube wall 3352 defining a hollow interior along the length of the tube 3350 (e.g. forming a conduit). The pressurised flow of air is able to travel from the connection port 3600, through the hollow interior within the tube wall 3352 for delivery to the seal-forming structure 3100.

In the example illustrated in Figs. 11A-11C, the tube 3350 comprises a tab 3320. In this example the tabs 3320 of the positioning and stabilising structure 3300 are each integrally formed with a respective tube wall 3352 of the tubes 3350.

Alternatively, the tabs 3320 may be separate parts assembled with the tube 3350. For example, the tabs 3320 may comprise separate components that movably connect to the tubes 3350 to enable adjustment of the position and/or angle of the tabs 3320. ally forming the tabs 3320 with the tube walls 3352 may improve the ity of the positioning and stabilising structure 3300 by reducing the assembly required.

Additionally, integrally formed tabs 3320 may enable a seamless tion between tabs 3320 and tube walls 3352, reducing the possibility of the connection causing discomfort to the patient.

In the illustrated example, each of the tubes 3350 comprises an able tube section in the form of an able concertina structure 3362. Each tab 3320 is joined to the tube wall 3352 of the gas delivery tube 3350 inferior to the extendable tube section. In ular, each tab 3320 is joined to the tube wall 3352 of the gas delivery tube 3350 at a non-extendable tube section 3363 inferior to the extendable tube section. In some examples the tabs 3320 may each have a or edge 3331 spaced along the length of the tube 3350 from an end of the extendable tube section.

P1415NZ7 / 506176NZDIV6 In other examples the tabs 3320 may have superior edges 3331 which meet the tube wall 3352 at or proximate an inferior end of the extendable tube section.

In the examples illustrated in Figs. C, the slits 3322 of the tubes 3350 are formed in the tabs 3320. In other es, slits 3322 may be formed directly into the tube wall 3352 or may be formed into another portion of the oning and stabilising structure 3300 or a separate component configured to connect to the positioning and stabilising structure 3300.

The slits 3322 may each be spaced posteriorly in use from the tube wall of the respective tube 3350. In particular, each slit 3322 may be spaced posteriorly from djacent portion 3355 of the tube wall 3352 alongside the respective slit 3322.

The slit-adjacent portion 3355 of the tube wall 3352 may be the n of the tube wall 3352 to which the tab 3320 is connected. More particularly, the slit-adjacent portion 3355 of the tube wall 3352 may be the portion of the tube wall 3352 that is most adjacent to the slit 3322. In some examples, the slit 3322 may be spaced posteriorly with respect to the entire length of the tube wall 3352. The slit 3322 may be located superior to the otobasion superior of the patient’s head in use.

In the manner illustrated in Figs. 8A-8C, each of the tube walls 3352 are configured to overlie the patient’s head along a path 3353 passing between an eye and an ear of the patient. A portion of the path 3353 is illustrated in Figs. 11A and 11B. In some examples, the path 3353 is generally the path on the surfaces of the patient’s head over and along which the tube walls 3350 lie. Additionally, the path 3353 may be the path along which gas flowing through the tubes 3350 s from the top of the patient’s head to the seal-forming structure 3100. In practice, the path 3353 may comprise a curve in three-dimensional space (e.g. a space curve), since in some examples the path 3353 may not be confined to a plane. In the rated examples, the tubes 3350 track laterally and inferiorly over the sides of the patient’s head and then inferiorly, anteriorly and medially to connect with the cradle cushion module 3150.

As illustrated in Figs. 11A-11C, each of the slits 3322 comprises a superior end 3326 and an inferior end 3327. The superior end 3326 and or end 3327 may also be considered first and second ends, respectively. In this example, the P1415NZ7 / 506176NZDIV6 or end 3326 is spaced further from the slit-adjacent portion 3355 of the tube wall 3352 than the inferior end 3327. As shown in Fig. 11A, the superior end 3326 of the slit 3322 is spaced from the tube wall 3352 by a spacing identified with SE in the illustration. The inferior and 3327 of the slit 3322 is spaced from the tube wall 3352 by a spacing identified with IE. As illustrated, the g SE is larger than the spacing IE and, ingly, the or end 3326 is spaced further from the tube wall 3352 than the inferior end 3327. When a patient has donned a patient interface 3000 including the positioning and stabilising structure 3300, the superior end 3326 is spaced posteriorly with respect to the inferior end 3327. Unless the context clearly requires otherwise, if an end of a slit or eyelet is described as being spaced further from a tube wall than r end of the slit or eyelet, the spacing referred to is to be understood to be with respect to a generally adjacent or t portion of the tube wall to the slit or eyelet (e.g. a slit-adjacent or eyelet-adjacent portion).

As illustrated in Fig. 11B, the slit 3322 is oriented at an angle with respect to the orientation of the tube 3350 at a djacent portion 3355 of the tube wall 3352. The slit 3322 is also oriented at an angle with t to the path 3353 at the slit-adjacent portion 3355 of the tube wall 3352. In this e, the slit 3322 is arcuate between the superior end 3326 and the inferior end 3327. The slits 3322 each have a curved elongate shape. In other examples, each slit 3322 may be straight between the superior end 3326 and the inferior end 3327. The curved, arcuate shape of the slits 3322 may advantageously enable a strap 3310 passing through the slit to centre within the slit 3322 and may also allow the slit 3322 to tolerate some variation in the angle of the strap 3310 passing through the slit 3322, without causing the strap 3310 to bunch up towards one end of the slit 3322.

Illustrated in Fig. 11B is a length axis 3323 of the slit 3322. The length axis 3323 in this example is d along the general length of the slit 3322 as the slit is elongate. An arcuate slit 3322, such as the slit 3322 shown in Figs 11A-C may still comprise a length axis as it is elongate. It will be appreciated that in the case of an arcuate slit 3322, the length axis 3323 may not be parallel with every portion of the sides of the slit 3322 but may be defined by the general direction from one end of the slit 3322 to the other. Alternatively, the length axis 3323 of an arcuate slit 3322 may P1415NZ7 / 506176NZDIV6 be defined by a tangent to the curvature of the slit 3322 at a central portion of the slit 3322.

The slit 3322 may have a osuperior-anteroinferior orientation in use.

That is, the length of the slit 3322 (e.g. the length axis 3323) may be aligned parallel to a line extending n a posterosuperior direction and an anteroinferior direction. With this orientation, the superior end 3326 of the slit 3322 is spaced posteriorly with t to the inferior end 3327 of the slit 3322. Illustrated in Fig. 11B is a tangent 3354 to the path 3353 at the slit-adjacent n 3355 of the tube 3350. As shown, the length axis 3323 of the slit 3322 forms a slit angle 3321 with the t 3354 of the path 3353. In this example, the slit angle 3321 is an oblique angle.

The oblique angle may be in the range of 5 to 30 degrees. In some examples, the oblique angle may be within the range of 10 to 20 degrees. For example, the oblique angle may be within the range of 12 to 18 degrees. In specific examples, the e angle may be about 13 degrees, 15 degrees or 17 degrees. In some examples, the slit 3322 may angled with respect to a longitudinal axis along the length of the able concertina structure 3362. In particular, the slit 3322 may be oriented at an angle of between 15 and 45 degrees with respect to a longitudinal axis of the extendable concertina structure 3362 when straightened. For example, this angle may be within the range of 20 and 40 degrees, such as within the range of 22 and 35 degrees. In particular examples, the angle may be about 25 degrees or 31 s with respect to the longitudinal axis of the extendable concertina structure 3362 when straightened.

A slit 3322 that is angled posteriorly with respect to the tube wall 3352 or path 3353 (e.g. with the superior end 3326 being spaced further from the tube wall 3352 or path 3353 than the inferior end 3327) may advantageously be better suited to receive the strap 3310 from a lower position around the back of the patient’s head. In an ideal set up, the strap 3310 extends from the slit 3322 in a direction perpendicular to the length axis 3323 of the slit 3322. Therefore, a more iorly angled slit 3322 will better accommodate a strap 3310 that lies low around the back of the patient’s head, since it will be angled to receive the strap 3310 from the lower angle. In contrast, a slit 3322 that is oriented closer to a vertical orientation will be angled to receive the strap 3310 from a higher position on the patient’s head. Accordingly, a slit 3322 oriented at a larger angle with t to an adjacent portion of the tube wall P1415NZ7 / 506176NZDIV6 3352 and/or path 3353 may provide some resistance to the strap 3310 riding up the back of the patient’s head (e.g. sliding superiorly).

While other methods may be used to reduce the tendency of the strap 3310 to ride up the back of the patient’s head (e.g. ing a split in the strap 3310, enabling the patient to tighten the strap 3310 and/or providing the slit 3322 at a low position) ing the slit 3322 at a posteriorly rotated angle to the tube 3350 may provide further resistance to the strap 3310 riding up. In some examples, each slit 3322 may be angled to receive the strap 3310 from a direction in which the strap 3310 lies across a region of the patient’s head overlaying an inferior portion of the occipital bone. In further examples, the slit 3322 may be angled to receive the strap 3310 from the direction which the strap 3310 overlays a central or superior portion of the patient’s occipital bone.

Each slit 3322 may be oriented perpendicular to the direction from the slit of a strap anchor region t which the strap is anchored around the t’s head.

The strap anchor region may be a region overlaying the patient’s occipital bone, for example an inferior n of the occipital bone. In some examples the strap anchor region may be a region of the patient’s neck lying inferior to the t’s occipital bone. In some examples, in some examples the strap 3310 may y a superior n of the patient’s trapezius muscles or a portion of the patient’s neck or head inferior to the occipital bone and the slit 3322 may be angled to receive the strap 3310 from a corresponding direction.

For example, as shown in Fig. 8C, the slit 3322 is angled sufficiently rearward to receive the strap 3310 from a direction in which the strap 3310 lies across a posterior region of the patient’s head or to an inferior-most portion of the patient’s head. The strap 3310 may lie across posterior surfaces of the t’s head that face in an at least partially inferior direction and the slit 3322 may be angled sufficiently posteriorly to receive the strap 3310 from this location. It is advantageous for the strap 3310 to lie across posterior surfaces of the patient’s head that face in an at least partially inferior direction since the eyelets are located superior to the ior-most portion of the strap 3310. Once tension is applied to the strap 3310, the tubes 3350 will exert a partially superior force on the strap 3310, meaning the strap P1415NZ7 / 506176NZDIV6 3310 may be less likely to ride up if anchored against posterior surfaces of the patient’s head that face inferiorly.

With reference to Figs. 11A-11C, the tab 3320 comprises a superior edge 3331 and an inferior edge 3332. In this example, the superior edge 3331 is longer than the inferior edge 3332. The longer superior edge 3331 gives the tab 3320 an trical shape pointing in more of an inferior direction than the tab 3320 would point if the superior edge 3331 was of an equal length to the inferior edge 3332. The slit 3322 is substantially centred between the superior edge 3331 and an inferior edge 3332. Thus, the asymmetrical shape of the tab 3320 result in the slit 3322 being presented s more of an inferior direction. This inferior pointing of the tab 3320 may advantageously reduce the tendency of the strap 3310 from riding up the back of the patient’s head.

In addition to having an e slit angle 3321, the slit 3322 may also be spaced from the tube wall 3352 by a spacing ient to further reduce a cy of the strap 3310 to ride up the back of the patient’s head. A generous spacing between a slit or other eyelet and the tube wall 3352 advantageously may reduce the distance between the eyelet and the back of the patient’s head. A relatively short ce between the eyelet and the back of the patient’s head may reduce the length of the strap 3310 that lies laterally alongside the t’s head extending between the slit 3322 and the posteriorly facing the forces of the patient’s head. This reduced distance and strap length may ageously inhibit pivoting of the strap 3310 with respect to the eyelet, thereby reducing the tendency of the strap 3310 to ride upwardly or downwardly in use.

In some examples, the inferior end 3327 of the slit 3322 may be spaced from the tube wall 3352 by at least 5 mm. In further examples, the inferior end 3327 of the slit 3322 may be spaced from the tube wall 3352 by at least 7 mm. For example, the inferior end 3327 of the slit 3322 may be spaced from the tube wall 3352 by about 8 mm, or more.

The superior end 3326 of the slit 3322 may be spaced from the tube wall 3352 by at least 8 mm. In some examples, the superior end 3326 of the slit 3322 may P1415NZ7 / 506176NZDIV6 be spaced from the tube wall 3352 by at least 10 mm. For example, the superior end 3326 of the slit 3322 may be spaced from the tube wall 3352 by 12 mm, or more.

In some examples, a midpoint along the slit 3322 may be spaced from the tube wall 3352 by a g within a range of approximately 5mm to 30mm. A very large spacing between the eyelet and the tube wall 3352, while advantageous in sing stability of the strap 3310, may introduce challenges/problems in manufacturability, weight, comfort and aesthetic appear due to the sed size of the tabs 3320. A spacing within the 5-30mm range, such as with a range of 7mm to 20mm, may provide the benefits of stability to prevent the rear headgear strap 3310 riding up, which ng or minimising issues caused by the increased size of the tabs 3320. In r examples this spacing may be within a range of 8mm to 15mm, such as within the range of 9mm to 13mm. In some particular examples the spacing may be around 9mm to 11mm, such as about 9.5mm or 9.75mm. .3.2.3.3 Trough Fig. 11C shows a close-up perspective view of one of the tabs 3320 of the positioning and stabilising structure 3300. As illustrated, in some examples, the tab 3320 of the positioning and stabilising structure 3300 may comprise a trough 3324 formed in the tab and located posteriorly to the slit 3322. The trough 3324 may be formed into the body of the tab 3320 in a location underneath the strap 3310. The trough 3324, in this example, is provided between the slit 3322 and a ior side 3329 of the tab 3320. The tab 3320 may comprise an outwardly facing tab surface 3328 on the side of the tab 3320 facing away from the patient (e.g. in a lateral direction). The tab surface 3328 may be substantially planar in the vicinity of the slit 3322. The trough 3324 may be formed by a portion of the tab 3320 at the trough 3324 having a lesser material thickness than other portions of the tab 3320. The trough 3324 is therefore recessed with respect to the tab surface 3328 in this example.

The trough 3324 may have substantially the same width as the length of the slit 3322. That is, the trough 3324 may have a superior end ate the superior end 3326 of the slit and may have an inferior end proximate the inferior end 3327 of the slit 3322. In this example, the trough 3324 has substantially the same width as the strap 3310. The trough 3324 is configured to receive the strap 3310. The trough 3324 reduces the total thickness of the strap 3310 and tab 3320. At the location of the P1415NZ7 / 506176NZDIV6 trough 3324, the tab 3320 is sandwiched between two layers of the strap 3310 (since the strap is threaded through the slit and looped back on itself). The bulk and/or thickness of the strap 3310 and tab 3320 at this location may create a pressure point or point of discomfort for the patient when sleeping on their side. The trough 3324 may advantageously reduce the layered thickness of ents at this location which may reduce the pressure applied to the patient’s head at this location during side sleeping.

Additionally, in this example, the trough 3324 has sides which are adjacent to sides of the strap 3310. The width of the trough 3324 therefore s the width of the strap 3310. This advantageously may help keep the strap 3310 aligned and centred within the trough 3324. It may also provide a visual guide for the user ing alignment of the strap 3310. .3.3 Vent In one form, the patient interface 3000 includes a vent 3400 constructed and arranged to allow for the washout of exhaled gases, e.g. carbon dioxide.

In certain forms the vent 3400 is configured to allow a continuous vent flow from an interior of the plenum chamber 3200 to ambient whilst the re within the plenum chamber is positive with respect to t. The vent 3400 is ured such that the vent flow rate has a magnitude sufficient to reduce rebreathing of exhaled CO2 by the patient while maintaining the therapeutic pressure in the plenum chamber in use. The vent 3400 may e a continuous vent flow of gas from the interior of the plenum chamber 3200 to ambient throughout the patient’s respiratory cycle.

One form of vent 3400 in accordance with the present technology comprises a plurality of holes, for example, about 20 to about 80 holes, or about 40 to about 60 holes, or about 45 to about 55 holes.

The vent 3400 may be located in the plenum chamber 3200. Alternatively, the vent 3400 is located in a decoupling structure, e.g., a swivel such as elbow 3610.

In the example shown in Figs. 8A-9C, the t interface 3000 comprises a plurality of vents 3400. In particular, the patient interface 3000 comprises at least one vent P1415NZ7 / 506176NZDIV6 3400 in the plenum chamber 3200 and at least one vent in the elbow 3610. More particularly, the plenum chamber 3200 comprises two vents 3400. Each vent 3400 on the plenum chamber 3200 comprises an array of holes. The vent 3400 on the elbow 3610 also comprises an array of holes. The vent 3400 of the patient interface 3000 are sized and configured to provide sufficient gas washout throughout a range of therapeutic pressures.

The patient interface 3000 may comprise a er configured to diffuse the flow of air though the vent to reduce vent noise and reduce jetting of air out of the vent holes. The diffuser may be provided to a cover over the vent holes. In some examples, the vent 3400 may comprise a vent module configured to be removed from the plenum chamber 3200. The vent module may comprise a er. .3.4 Decoupling structure(s) In one form the patient interface 3000 includes at least one ling structure, for example, a swivel or a ball and . For example, the patient ace 3000 shown in Figs. 8A-9C ses an elbow 3610 configured the swivel with respect to the positioning and stabilising structure 3300. In this example the elbow 3610 is configured to swivel about an axis concentric with a circular opening in the oning and stabilising structure 3300. In some examples of the present technology, the elbow 3610 may form part of a ball and socket joint to the positioning and stabilising structure 3300. For example, a ring having a partially spherical inner surface may be provided to the positioning and stabilising structure 3300 and may be configured to receive the elbow 3610. The elbow 3610 may have partially spherical outer surface mentary to the partially spherical inner surface of the ring, thereby enabling the elbow 3610 to swivel with respect to the ring in a plurality of axes. .3.5 Connection port Connection port 3600 allows for connection to the air circuit 4170. In the ary patient ace 3000 shown in Figs. 8A-9C, the elbow 3610 forms part of the connection port 3600. The elbow 3610, as a decoupling structure, decouples movement of the air circuit 4170 from the positioning and stabilising structure 3300 in order to reduce tube drag on the positioning and stabilising structure 3300.

P1415NZ7 / 506176NZDIV6 .3.6 Forehead support In one form, the patient interface 3000 includes a forehead support 3700.

In other forms, the patient interface 3000 does not include a forehead support.

Advantageously, the exemplary patient interface 3000 shown in Figs. 8A-9C comprises a oning and ising structure 3300 that is able to hold the sealforming structure 3100 in sealing position without connection to a forehead support or any frame or strap members that lie in front of the patient’s face at eye level. .3.7 Anti-asphyxia valve In one form, the patient interface 3000 includes an anti-asphyxia valve. In some es, the patient interface 3000 es a plurality of anti-asphyxia valves.

For example, where airflow is provided to a seal-forming structure 3100 via two fluid connections, two anti-asphyxia valves may be provided to the patient interface 3000, one at each fluid connection to the seal-forming structure 3100. .3.8 Ports In one form of the t technology, a patient interface 3000 es one or more ports that allow access to the volume within the plenum chamber 3200.

In one form this allows a clinician to supply supplemental oxygen. In one form, this allows for the direct measurement of a property of gases within the plenum chamber 3200, such as the pressure. .4 RPT DEVICE An RPT device 4000 in accordance with one aspect of the present technology ses mechanical, pneumatic, and/or electrical components and is configured to execute one or more algorithms 4300, such as any of the methods, in whole or in part, described herein. The RPT device 4000 may be configured to generate a flow of air for delivery to a patient’s airways, such as to treat one or more of the respiratory conditions bed elsewhere in the t document.

In one form, the RPT device 4000 is constructed and arranged to be capable of delivering a flow of air in a range of -20 L/min to +150 L/min while maintaining a positive pressure of at least 6 cmH2O, or at least 10cmH2O, or at least cmH2O.

P1415NZ7 / 506176NZDIV6 The RPT device may have an external housing 4010, formed in two parts, an upper portion 4012 and a lower portion 4014. Furthermore, the external housing 4010 may include one or more panel(s) 4015. The RPT device 4000 comprises a chassis 4016 that supports one or more internal components of the RPT device 4000.

The RPT device 4000 may include a handle 4018.

The pneumatic path of the RPT device 4000 may comprise one or more air path items, e.g., an inlet air filter 4112, an inlet muffler 4122, a pressure generator 4140 capable of supplying air at positive pressure (e.g., a blower 4142), an outlet muffler 4124 and one or more transducers 4270, such as pressure sensors and flow rate s.

One or more of the air path items may be located within a removable unitary structure which will be referred to as a pneumatic block 4020. The pneumatic block 4020 may be located within the external housing 4010. In one form a pneumatic block 4020 is supported by, or formed as part of the chassis 4016.

The RPT device 4000 may have an electrical power supply 4210, one or more input devices 4220, a central controller, a therapy device controller, a pressure generator 4140, one or more tion circuits, memory, transducers 4270, data communication interface and one or more output devices. Electrical components 4200 may be d on a single Printed Circuit Board Assembly (PCBA) 4202. In an alternative form, the RPT device 4000 may include more than one PCBA 4202. .4.1 RPT device mechanical & tic components An RPT device may comprise one or more of the following components, including tic components 4100, in an integral unit. In an alternative form, one or more of the following ents may be located as respective separate units. .4.1.1 Air filter(s) An RPT device in ance with one form of the present technology may include an air filter 4110, or a plurality of air filters 4110.

In one form, an inlet air filter 4112 is located at the ing of the pneumatic path am of a pressure generator 4140.

P1415NZ7 / NZDIV6 In one form, an outlet air filter 4114, for example an antibacterial filter, is located between an outlet of the pneumatic block 4020 and a patient interface 3000. 2 Muffler(s) An RPT device in accordance with one form of the present technology may include a muffler 4120, or a plurality of mufflers 4120.

In one form of the present technology, an inlet muffler 4122 is located in the pneumatic path upstream of a pressure generator 4140.

In one form of the present technology, an outlet muffler 4124 is located in the pneumatic path n the re generator 4140 and a patient interface 3000. .4.1.3 Pressure generator In one form of the present technology, a pressure generator 4140 for producing a flow, or a supply, of air at positive pressure is a controllable blower 4142.

For example the blower 4142 may include a brushless DC motor 4144 with one or more impellers. The impellers may be located in a volute. The blower may be capable of delivering a supply of air, for e at a rate of up to about 120 litres/minute, at a positive pressure in a range from about 4 cmH2O to about 20 cmH2O, or in other forms up to about 30 cmH2O. The blower may be as described in any one of the following patents or patent applications the contents of which are orated herein by reference in their entirety: U.S. Patent No. 7,866,944; U.S. Patent No. 8,638,014; U.S. Patent No. 8,636,479; and PCT Patent Application Publication No. WO 2013/020167.

The pressure generator 4140 is under the control of the therapy device controller 4240.

In other forms, a pressure generator 4140 may be a piston-driven pump, a pressure tor ted to a high pressure source (e.g. compressed air reservoir), or a bellows. .4.1.4 Anti-spill back valve In one form of the present technology, an anti-spill back valve 4160 is located n the humidifier 5000 and the pneumatic block 4020. The anti-spill P1415NZ7 / 506176NZDIV6 back valve is ucted and arranged to reduce the risk that water will flow upstream from the humidifier 5000, for example to the motor 4144. .4.2 RPT device algorithms As mentioned above, in some forms of the present technology, the central controller may be configured to implement one or more algorithms expressed as computer programs stored in a non-transitory computer readable storage medium, such as memory. The algorithms are generally grouped into groups ed to as .5 AIR CIRCUIT An air circuit 4170 in accordance with an aspect of the present technology is a conduit or a tube constructed and arranged to allow, in use, a flow of air to travel between two components such as RPT device 4000 and the patient interface 3000.

In particular, the air circuit 4170 may be in fluid connection with the outlet of the pneumatic block 4020 and the patient interface. The air circuit may be referred to as an air ry tube. In some cases there may be separate limbs of the circuit for inhalation and exhalation. In other cases a single limb is used.

In some forms, the air circuit 4170 may comprise one or more heating elements configured to heat air in the air circuit, for example to maintain or raise the temperature of the air. The g element may be in a form of a heated wire t, and may comprise one or more transducers, such as ature sensors. In one form, the heated wire circuit may be lly wound around the axis of the air circuit 4170.

The heating element may be in ication with a controller such as a central controller. One example of an air circuit 4170 comprising a heated wire circuit is described in United States Patent 8,733,349, which is incorporated herewithin in its entirety by reference. .5.1 Oxygen delivery In one form of the present technology, supplemental oxygen 4180 is delivered to one or more points in the tic path, such as upstream of the pneumatic block 4020, to the air circuit 4170 and/or to the patient interface 3000.

P1415NZ7 / 506176NZDIV6 .6 HUMIDIFIER .6.1 Humidifier overview In one form of the present technology there is provided a humidifier 5000 (e.g. as shown in Fig. 5A) to change the absolute humidity of air or gas for delivery to a t relative to ambient air. Typically, the humidifier 5000 is used to increase the absolute humidity and increase the temperature of the flow of air (relative to ambient air) before delivery to the patient’s airways.

The humidifier 5000 may comprise a humidifier reservoir 5110, a humidifier inlet 5002 to receive a flow of air, and a humidifier outlet 5004 to deliver a fied flow of air. In some forms, as shown in Fig. 5A and Fig. 5B, an inlet and an outlet of the humidifier reservoir 5110 may be the humidifier inlet 5002 and the humidifier outlet 5004 respectively. The humidifier 5000 may further comprise a humidifier base 5006, which may be adapted to receive the humidifier reservoir 5110 and comprise a heating element 5240. .6.1.1 Conductive n According to one arrangement, the reservoir 5110 comprises a conductive portion 5120 ured to allow efficient transfer of heat from the g element 5240 to the volume of liquid in the reservoir 5110. In one form, the conductive portion 5120 may be arranged as a plate, although other shapes may also be suitable.

All or a part of the conductive portion 5120 may be made of a thermally tive material such as aluminium (e.g. approximately 2 mm thick, such as 1 mm, 1.5 mm, 2.5 mm or 3 mm), another heat conducting metal or some plastics. In some cases, suitable heat conductivity may be achieved with less tive materials of suitable geometry. 2 Humidifier reservoir dock In one form, the fier 5000 may comprise a humidifier reservoir dock 5130 (as shown in Fig. 5B) configured to receive the fier reservoir 5110.

In some ements, the humidifier reservoir dock 5130 may comprise a locking feature such as a locking lever 5135 configured to retain the reservoir 5110 in the humidifier reservoir dock 5130.

P1415NZ7 / 506176NZDIV6 .6.1.3 Water level indicator The humidifier reservoir 5110 may comprise a water level indicator 5150 as shown in Fig. 5A-5B. In some forms, the water level tor 5150 may provide one or more indications to a user such as the patient 1000 or a care giver regarding a quantity of the volume of water in the humidifier reservoir 5110. The one or more indications provided by the water level indicator 5150 may include an indication of a maximum, predetermined volume of water, any portions thereof, such as 25%, 50% or 75% or s such as 200 ml, 300 ml or 400ml. .7 GLOSSARY For the purposes of the present technology disclosure, in n forms of the present technology, one or more of the ing tions may apply. In other forms of the present technology, alternative definitions may apply. .7.1 General Air: In certain forms of the present technology, air may be taken to mean atmospheric air, and in other forms of the t technology air may be taken to mean some other combination of breathable gases, e.g. atmospheric air enriched with oxygen.

Ambient: In certain forms of the present technology, the term ambient will be taken to mean (i) external of the treatment system or patient, and (ii) immediately nding the treatment system or t.

For example, ambient humidity with respect to a humidifier may be the humidity of air immediately surrounding the humidifier, e.g. the humidity in the room where a patient is sleeping. Such t humidity may be different to the humidity outside the room where a patient is sleeping.

In another example, ambient pressure may be the pressure immediately surrounding or external to the body.

In certain forms, ambient (e.g., acoustic) noise may be considered to be the background noise level in the room where a patient is located, other than for example, noise ted by an RPT device or emanating from a mask or patient interface. Ambient noise may be generated by sources outside the room.

P1415NZ7 / 506176NZDIV6 Automatic Positive Airway Pressure (APAP) therapy: CPAP therapy in which the treatment pressure is automatically able, e.g. from breath to , between minimum and maximum , ing on the presence or absence of indications of SDB events.

Continuous Positive Airway Pressure (CPAP) therapy: Respiratory pressure therapy in which the ent pressure is approximately constant through a respiratory cycle of a patient. In some forms, the pressure at the entrance to the airways will be slightly higher during exhalation, and ly lower during inhalation.

In some forms, the pressure will vary n different respiratory cycles of the patient, for example, being increased in se to detection of indications of partial upper airway obstruction, and decreased in the absence of indications of partial upper airway obstruction.

Flow rate: The volume (or mass) of air red per unit time. Flow rate may refer to an instantaneous quantity. In some cases, a reference to flow rate will be a reference to a scalar quantity, namely a quantity having magnitude only. In other cases, a reference to flow rate will be a reference to a vector ty, namely a quantity having both magnitude and direction. Flow rate may be given the symbol Q.

‘Flow rate’ is sometimes shortened to simply ‘flow’ or ow’.

In the example of patient respiration, a flow rate may be nominally positive for the inspiratory portion of a breathing cycle of a patient, and hence negative for the expiratory portion of the breathing cycle of a patient. Total flow rate, Qt, is the flow rate of air leaving the RPT device. Vent flow rate, Qv, is the flow rate of air leaving a vent to allow washout of exhaled gases. Leak flow rate, Ql, is the flow rate of leak from a patient interface system or elsewhere. Respiratory flow rate, Qr, is the flow rate of air that is received into the patient's respiratory system.

Humidifier: The word humidifier will be taken to mean a humidifying apparatus constructed and arranged, or configured with a physical structure to be capable of providing a therapeutically beneficial amount of water (H2O) vapour to a flow of air to ameliorate a medical respiratory ion of a patient.

P1415NZ7 / 506176NZDIV6 Leak: The word leak will be taken to be an unintended flow of air. In one example, leak may occur as the result of an incomplete seal between a mask and a patient's face. In another e leak may occur in a swivel elbow to the ambient.

Noise, conducted (acoustic): Conduc ted noise in the t document refers to noise which is carried to the patient by the pneumatic path, such as the air t and the patient interface as well as the air therein. In one form, conducted noise may be quantified by measuring sound re levels at the end of an air circuit.

Noise, radiated (acoustic): Radiated noise in the present document refers to noise which is carried to the patient by the ambient air. In one form, radiated noise may be fied by measuring sound power/pressure levels of the object in question according to ISO 3744.

Noise, vent (acoustic): Vent noise in the present document refers to noise which is generated by the flow of air through any vents such as vent holes of the patient interface.

Patient: A person, whether or not they are suffering from a respiratory condition.

Pressure: Force per unit area. Pressure may be expressed in a range of units, including cmH2O, g-f/cm2 and hectopascal. 1 cmH2O is equal to 1 g-f/cm2 and is approximately 0.98 hectopascal. In this ication, unless otherwise stated, pressure is given in units of cmH2O.

The pressure in the patient interface is given the symbol Pm, while the treatment re, which represents a target value to be achieved by the mask pressure Pm at the current instant of time, is given the symbol Pt.

Respiratory Pressure Therapy (RPT): The application of a supply of air to an entrance to the airways at a treatment pressure that is typically ve with respect to atmosphere.

Ventilator: A mechanical device that es pressure support to a patient to perform some or all of the work of breathing.

P1415NZ7 / 506176NZDIV6 .7.1.1 als Silicone or Silicone Elastomer: A synthetic rubber. In this specification, a reference to silicone is a reference to liquid silicone rubber (LSR) or a compression moulded silicone rubber (CMSR). One form of commercially available LSR is IC (included in the range of products sold under this trademark), ctured by Dow Corning. Another cturer of LSR is . Unless otherwise specified to the contrary, an exemplary form of LSR has a Shore A (or Type A) indentation hardness in the range of about 35 to about 45 as measured using ASTM D2240.

Polycarbonate: a thermoplastic polymer of Bisphenol-A Carbonate. .7.1.2 Mechanical ties Resilience: Ability of a material to absorb energy when deformed elastically and to release the energy upon unloading.

Resilient: Will release substantially all of the energy when unloaded.

Includes e.g. certain silicones, and thermoplastic elastomers.

Hardness: The y of a material per se to resist deformation (e.g. described by a Young’s Modulus, or an indentation ss scale measured on a standardised sample size).

• ‘Soft’ materials may include silicone or thermo-plastic elastomer (TPE), and may, e.g. readily deform under finger pressure.

• ‘Hard’ materials may include rbonate, polypropylene, steel or aluminium, and may not e.g. readily deform under finger pressure.

Stiffness (or rigidity) of a structure or component: The ability of the structure or component to resist deformation in response to an applied load. The load may be a force or a moment, e.g. compression, tension, bending or n. The ure or component may offer different resistances in different directions.

Floppy structure or component: A structure or component that will change shape, e.g. bend, when caused to support its own weight, within a relatively short period of time such as 1 second.

P1415NZ7 / 506176NZDIV6 Rigid structure or component: A structure or component that will not substantially change shape when subject to the loads typically encountered in use. An example of such a use may be setting up and maintaining a patient interface in sealing relationship with an entrance to a patient's airways, e.g. at a load of approximately 20 to 30 cmH2O pressure.

As an e, an I-beam may comprise a different bending stiffness (resistance to a g load) in a first direction in comparison to a second, orthogonal direction. In another example, a structure or component may be floppy in a first direction and rigid in a second direction. .7.2 atory cycle Apnea: According to some definitions, an apnea is said to have occurred when flow falls below a predetermined threshold for a duration, e.g. 10 seconds. An obstructive apnea will be said to have occurred when, despite patient effort, some obstruction of the airway does not allow air to flow. A central apnea will be said to have ed when an apnea is detected that is due to a reduction in breathing effort, or the e of breathing , e the airway being patent. A mixed apnea occurs when a reduction or absence of breathing effort coincides with an obstructed airway. .7.3 Anatomy 1 Anatomy of the face Ala: the external outer wall or "wing" of each nostril (plural: alar) Alare: The most lateral point on the nasal ala.

Alar curvature (or alar crest) point: The most posterior point in the curved base line of each ala, found in the crease formed by the union of the ala with the cheek.

Auricle: The whole al visible part of the ear. (nose) Bony framework: The bony framework of the nose comprises the nasal bones, the frontal process of the maxillae and the nasal part of the frontal bone.

P1415NZ7 / 506176NZDIV6 (nose) Cartilaginous framework: The cartilaginous framework of the nose comprises the septal, lateral, major and minor cartilages.

Columella: the strip of skin that separates the nares and which runs from the pronasale to the upper lip.

Columella angle: The angle between the line drawn through the midpoint of the nostril aperture and a line drawn dicular to the Frankfort horizontal while intersecting subnasale.

Frankfort ntal plane: A line extending from the most inferior point of the orbital margin to the left tragion. The tragion is the deepest point in the notch superior to the tragus of the auricle.

Glabella: Located on the soft tissue, the most prominent point in the midsagittal plane of the ad.

Lateral nasal cartilage: A generally triangular plate of cartilage. Its superior margin is ed to the nasal bone and frontal process of the maxilla, and its inferior margin is connected to the greater alar cartilage. r alar cartilage: A plate of age lying below the lateral nasal cartilage. It is curved around the anterior part of the naris. Its posterior end is connected to the frontal process of the a by a tough fibrous membrane containing three or four minor cartilages of the ala.

Nares (Nostrils): imately ellipsoidal apertures forming the entrance to the nasal cavity. The singular form of nares is naris (nostril). The nares are separated by the nasal septum.

Naso-labial sulcus or Naso-labial fold: The skin fold or groove that runs from each side of the nose to the corners of the mouth, separating the cheeks from the upper lip.

Naso-labial angle: The angle between the columella and the upper lip, while intersecting subnasale.

P1415NZ7 / 506176NZDIV6 Otobasion inferior: The lowest point of ment of the auricle to the skin of the face.

Otobasion superior: The highest point of attachment of the auricle to the skin of the face. ale: the most protruded point or tip of the nose, which can be identified in lateral view of the rest of the portion of the head. um: the midline groove that runs from lower border of the nasal septum to the top of the lip in the upper lip region.

Pogonion: d on the soft tissue, the most anterior midpoint of the chin.

Ridge (nasal): The nasal ridge is the midline prominence of the nose, extending from the Sellion to the Pronasale.

Sagittal plane: A vertical plane that passes from anterior (front) to posterior (rear). The midsagittal plane is a sagittal plane that divides the body into right and left halves.

Sellion: Located on the soft tissue, the most concave point overlying the area of the frontonasal suture.

Septal cartilage (nasal): The nasal septal age forms part of the septum and divides the front part of the nasal cavity.

Subalare: The point at the lower margin of the alar base, where the alar base joins with the skin of the superior (upper) lip.

Subnasal point: Located on the soft tissue, the point at which the columella merges with the upper lip in the midsagittal plane.

Supramenton: The point of st concavity in the midline of the lower lip between labrale inferius and soft tissue pogonion P1415NZ7 / 506176NZDIV6 .7.3.2 Anatomy of the skull l bone: The frontal bone includes a large vertical portion, the squama frontalis, corresponding to the region known as the ad.

Mandible: The mandible forms the lower jaw. The mental protuberance is the bony protuberance of the jaw that forms the chin.

Maxilla: The maxilla forms the upper jaw and is located above the mandible and below the orbits. The frontal process of the maxilla projects upwards by the side of the nose, and forms part of its lateral boundary.

Nasal bones: The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face, and form, by their junction, the "bridge" of the nose.

Nasion: The intersection of the frontal bone and the two nasal bones, a depressed area directly between the eyes and superior to the bridge of the nose.

Occipital bone: The occipital bone is situated at the back and lower part of the cranium. It includes an oval aperture, the foramen magnum, h which the l cavity communicates with the vertebral canal. The curved plate behind the foramen magnum is the squama occipitalis.

Orbit: The bony cavity in the skull to contain the eyeball.

Parietal bones: The al bones are the bones that, when joined together, form the roof and sides of the cranium.

Temporal bones: The al bones are situated on the bases and sides of the skull, and support that part of the face known as the temple.

Zygomatic bones: The face includes two zygomatic bones, d in the upper and lateral parts of the face and forming the prominence of the cheek. .7.3.3 y of the respiratory system Diaphragm: A sheet of muscle that extends across the bottom of the rib cage. The diaphragm separates the thoracic cavity, containing the heart, lungs and P1415NZ7 / 506176NZDIV6 ribs, from the abdominal cavity. As the diaphragm contracts the volume of the thoracic cavity increases and air is drawn into the lungs.

Larynx: The larynx, or voice box houses the vocal folds and connects the inferior part of the pharynx (hypopharynx) with the a.

Lungs: The organs of respiration in humans. The conducting zone of the lungs ns the trachea, the bronchi, the bronchioles, and the terminal bronchioles.

The respiratory zone contains the respiratory bronchioles, the alveolar ducts, and the alveoli.

Nasal cavity: The nasal cavity (or nasal fossa) is a large air filled space above and behind the nose in the middle of the face. The nasal cavity is divided in two by a vertical fin called the nasal septum. On the sides of the nasal cavity are three horizontal outgrowths called nasal e (singular "concha") or turbinates. To the front of the nasal cavity is the nose, while the back blends, via the choanae, into the nasopharynx.

Pharynx: The part of the throat situated immediately inferior to (below) the nasal , and superior to the oesophagus and larynx. The pharynx is conventionally divided into three sections: the nasopharynx (epipharynx) (the nasal part of the pharynx), the oropharynx (mesopharynx) (the oral part of the pharynx), and the laryngopharynx (hypopharynx). .7.4 t interface Anti-asphyxia valve (AAV): The component or sub-assembly of a mask system that, by opening to atmosphere in a failsafe manner, reduces the risk of ive CO2 rebreathing by a patient.

Elbow: An elbow is an e of a structure that directs an axis of flow of air travelling therethrough to change direction h an angle. In one form, the angle may be approximately 90 degrees. In another form, the angle may be more, or less than 90 degrees. The elbow may have an approximately circular cross-section. In another form the elbow may have an oval or a rectangular section. In certain forms an elbow may be rotatable with t to a mating component, e.g. about 360 degrees. In certain forms an elbow may be removable from a mating component, e.g.

P1415NZ7 / 506176NZDIV6 via a snap connection. In certain forms, an elbow may be assembled to a mating component via a me snap during manufacture, but not removable by a patient.

Frame: Frame will be taken to mean a mask structure that bears the load of tension between two or more points of connection with a headgear. A mask frame may be a non-airtight load bearing structure in the mask. However, some forms of mask frame may also be air-tight.

Headgear: Headgear will be taken to mean a form of positioning and izing structure designed for use on a head. For example the headgear may comprise a collection of one or more struts, ties and stiffeners configured to locate and retain a patient interface in position on a patient’s face for delivery of respiratory y. Some ties are formed of a soft, le, c material such as a laminated composite of foam and fabric.

Membrane: ne will be taken to mean a typically thin element that has, preferably, substantially no resistance to bending, but has resistance to being Plenum chamber: a mask plenum chamber will be taken to mean a portion of a patient interface having walls at least partially enclosing a volume of space, the volume having air therein pressurised above atmospheric pressure in use. A shell may form part of the walls of a mask plenum chamber.

Seal: May be a noun form ("a seal") which refers to a structure, or a verb form (“to seal”) which refers to the effect. Two elements may be constructed and/or arranged to ‘seal’ or to effect ‘sealing’ therebetween without requiring a separate ‘seal’ element per se.

Shell: A shell will be taken to mean a curved, relatively thin structure having bending, tensile and compressive ess. For e, a curved structural wall of a mask may be a shell. In some forms, a shell may be faceted. In some forms a shell may be airtight. In some forms a shell may not be airtight.

P1415NZ7 / 506176NZDIV6 Stiffener: A stiffener will be taken to mean a structural component designed to increase the bending ance of another component in at least one direction.

Strut: A strut will be taken to be a ural component designed to increase the compression resistance of another component in at least one ion.

Swivel (noun): A subassembly of components configured to rotate about a common axis, preferably independently, preferably under low torque. In one form, the swivel may be constructed to rotate through an angle of at least 360 degrees. In another form, the swivel may be constructed to rotate through an angle less than 360 degrees. When used in the context of an air delivery conduit, the sub-assembly of components preferably comprises a d pair of cylindrical conduits. There may be little or no leak flow of air from the swivel in use.

Tie (noun): A structure designed to resist tension.

Vent: (noun): A structure that allows a flow of air from an interior of the mask, or conduit, to ambient air for clinically effective washout of d gases. For example, a clinically effective washout may involve a flow rate of about 10 litres per minute to about 100 litres per minute, depending on the mask design and treatment pressure. .7.5 Shape of structures Products in accordance with the present logy may comprise one or more three-dimensional ical structures, for e a mask n or an er. The three-dimensional structures may be bounded by two-dimensional surfaces. These surfaces may be distinguished using a label to describe an associated surface ation, location, function, or some other characteristic. For example a structure may comprise one or more of an anterior surface, a posterior surface, an interior surface and an exterior surface. In another example, a seal-forming structure may comprise a face-contacting (e.g. outer) surface, and a separate non-facecontacting (e.g. underside or inner) surface. In another example, a structure may se a first surface and a second surface.

Z7 / 506176NZDIV6 To facilitate describing the shape of the three-dimensional structures and the surfaces, we first consider a cross-section through a surface of the structure at a point, p. See Fig. 3B to Fig. 3F, which illustrate examples of cross-sections at point p on a surface, and the resulting plane curves. Figs. 3B to 3F also illustrate an outward normal vector at p. The outward normal vector at p points away from the surface. In some examples we describe the surface from the point of view of an imaginary small person standing upright on the surface. .7.5.1 Curvature in one dimension The curvature of a plane curve at p may be described as having a sign (e.g. positive, negative) and a magnitude (e.g. 1/radius of a circle that just touches the curve at p).

Positive curvature: If the curve at p turns towards the outward normal, the ure at that point will be taken to be positive (if the imaginary small person leaves the point p they must walk uphill). See Fig. 3B (relatively large positive curvature compared to Fig. 3C) and Fig. 3C (relatively small positive ure compared to Fig. 3B). Such curves are often referred to as concave.

Zero curvature: If the curve at p is a straight line, the ure will be taken to be zero (if the imaginary small person leaves the point p, they can walk on a level, neither up nor down). See Fig. 3D.

Negative curvature: If the curve at p turns away from the outward normal, the curvature in that direction at that point will be taken to be negative (if the imaginary small person leaves the point p they must walk downhill). See Fig. 3E (relatively small negative curvature compared to Fig. 3F) and Fig. 3F ively large negative curvature compared to Fig. 3E). Such curves are often referred to as convex. .7.5.2 Curvature of two dimensional surfaces A description of the shape at a given point on a two-dimensional surface in accordance with the present logy may include multiple normal crosssections.

The multiple cross-sections may cut the surface in a plane that includes the outward normal (a “normal plane”), and each cross-section may be taken in a different direction. Each cross-section s in a plane curve with a ponding curvature.

P1415NZ7 / NZDIV6 The different curvatures at that point may have the same sign, or a different sign.

Each of the curvatures at that point has a ude, e.g. vely small. The plane curves in Figs. 3B to 3F could be examples of such multiple cross-sections at a particular point.

Principal curvatures and directions: The directions of the normal planes where the curvature of the curve takes its maximum and minimum values are called the principal directions. In the examples of Fig. 3B to Fig. 3F, the maximum ure occurs in Fig. 3B, and the minimum occurs in Fig. 3F, hence Fig. 3B and Fig. 3F are cross sections in the pal directions. The principal curvatures at p are the curvatures in the principal directions.

Region of a surface: A connected set of points on a surface. The set of points in a region may have similar characteristics, e.g. curvatures or signs.

Saddle region: A region where at each point, the principal curvatures have opposite signs, that is, one is positive, and the other is negative (depending on the direction to which the imaginary person turns, they may walk uphill or downhill).

Dome region: A region where at each point the principal curvatures have the same sign, e.g. both positive (a “concave dome”) or both negative (a “convex dome”). rical region: A region where one principal curvature is zero (or, for example, zero within manufacturing tolerances) and the other principal curvature is non-zero.

Planar : A region of a surface where both of the principal curvatures are zero (or, for example, zero within cturing nces).

Edge of a surface: A boundary or limit of a surface or region.

Path: In certain forms of the present technology, ‘path’ will be taken to mean a path in the mathematical – topological sense, e.g. a continuous space curve from f(0) to f(1) on a surface. In certain forms of the present technology, a ‘path’ may be described as a route or course, including e.g. a set of points on a surface. (The path P1415NZ7 / 506176NZDIV6 for the imaginary person is where they walk on the surface, and is analogous to a garden path).

Path length: In certain forms of the present technology, ‘path length’ will be taken to mean the distance along the surface from f(0) to f(1), that is, the distance along the path on the surface. There may be more than one path between two points on a surface and such paths may have ent path lengths. (The path length for the imaginary person would be the distance they have to walk on the surface along the path).

Straight-line distance: The straight-line distance is the distance between two points on a surface, but without regard to the surface. On planar regions, there would be a path on the surface having the same path length as the straight-line distance between two points on the surface. On non-planar surfaces, there may be no paths having the same path length as the straight-line distance between two points.

(For the imaginary , the ht-line distance would correspond to the distance ‘as the crow flies’.) .7.5.3 Space curves Space curves: Unlike a plane curve, a space curve does not necessarily lie in any particular plane. A space curve may be closed, that is, having no endpoints. A space curve may be considered to be a one-dimensional piece of three-dimensional space. An imaginary person walking on a strand of the DNA helix walks along a space curve. A l human left ear comprises a helix, which is a left-hand helix, see Fig. 3Q. A typical human right ear comprises a helix, which is a right-hand helix, see Fig. 3R. Fig. 3S shows a right-hand helix. The edge of a structure, e.g. the edge of a membrane or impeller, may follow a space curve. In general, a space curve may be described by a curvature and a torsion at each point on the space curve. Torsion is a measure of how the curve turns out of a plane. Torsion has a sign and a ude.

The torsion at a point on a space curve may be characterised with reference to the t, normal and binormal vectors at that point.

Tangent unit vector (or unit tangent vector): For each point on a curve, a vector at the point specifies a ion from that point, as well as a ude. A tangent unit vector is a unit vector pointing in the same direction as the curve at that P1415NZ7 / NZDIV6 point. If an imaginary person were flying along the curve and fell off her vehicle at a particular point, the direction of the tangent vector is the direction she would be travelling.

Unit normal vector: As the imaginary person moves along the curve, this tangent vector itself changes. The unit vector pointing in the same ion that the tangent vector is changing is called the unit principal normal vector. It is perpendicular to the tangent vector.

Binormal unit vector: The binormal unit vector is perpendicular to both the tangent vector and the principal normal vector. Its direction may be determined by a hand rule (see e.g. Fig. 3P), or alternatively by a left-hand rule (Fig. 3O).

Osculating plane: The plane containing the unit tangent vector and the unit pal normal vector. See s 3O and 3P.

Torsion of a space curve: The torsion at a point of a space curve is the magnitude of the rate of change of the binormal unit vector at that point. It measures how much the curve es from the osculating plane. A space curve which lies in a plane has zero n. A space curve which deviates a relatively small amount from the osculating plane will have a relatively small magnitude of torsion (e.g. a gently sloping helical path). A space curve which deviates a relatively large amount from the osculating plane will have a relatively large magnitude of torsion (e.g. a steeply sloping l path). With reference to Fig. 3S, since T2>T1, the magnitude of the torsion near the top coils of the helix of Fig. 3S is greater than the magnitude of the torsion of the bottom coils of the helix of Fig. 3S With reference to the right-hand rule of Fig. 3P, a space curve turning towards the direction of the hand binormal may be considered as having a righthand positive torsion (e.g. a right-hand helix as shown in Fig. 3S). A space curve turning away from the ion of the right-hand binormal may be considered as having a right-hand negative torsion (e.g. a left-hand helix).

Equivalently, and with reference to a left-hand rule (see Fig. 3O), a space curve turning towards the direction of the left-hand binormal may be considered as P1415NZ7 / 506176NZDIV6 having a and positive torsion (e.g. a and . Hence left-hand positive is equivalent to right-hand negative. See Fig. 3T. .7.5.4 Holes A surface may have a one-dimensional hole, e.g. a hole bounded by a plane curve or by a space curve. Thin structures (e.g. a membrane) with a hole, may be described as having a one-dimensional hole. See for example the one dimensional hole in the surface of structure shown in Fig. 3I, d by a plane curve.

A structure may have a two-dimensional hole, e.g. a hole bounded by a surface. For example, an inflatable tyre has a two dimensional hole bounded by the interior surface of the tyre. In another example, a bladder with a cavity for air or gel could have a two-dimensional hole. See for example the cushion of Fig. 3L and the example cross-sections therethrough in Fig. 3M and Fig. 3N, with the or surface bounding a two dimensional hole indicated. In a yet another example, a conduit may comprise a one-dimension hole (e.g. at its entrance or at its exit), and a mension hole bounded by the inside surface of the conduit. See also the two dimensional hole h the structure shown in Fig. 3K, bounded by a surface as shown. .8 OTHER REMARKS Unless the context clearly dictates otherwise and where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit, between the upper and lower limit of that range, and any other stated or intervening value in that stated range is encompassed within the technology. The upper and lower limits of these intervening ranges, which may be independently included in the intervening ranges, are also encompassed within the technology, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the technology.

Furthermore, where a value or values are stated herein as being implemented as part of the technology, it is understood that such values may be imated, unless otherwise stated, and such values may be ed to any suitable significant digit to the extent that a practical technical implementation may permit or require it.

P1415NZ7 / 506176NZDIV6 Unless defined ise, all technical and ific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology belongs. Although any methods and materials r or equivalent to those described herein can also be used in the practice or g of the present logy, a limited number of the exemplary methods and materials are described herein.

When a particular material is identified as being used to construct a component, obvious alternative materials with similar properties may be used as a substitute. Furthermore, unless specified to the ry, any and all components herein described are understood to be capable of being manufactured and, as such, may be manufactured together or separately.

It must be noted that as used herein and in the ed claims, the singular forms "a", "an", and "the" include their plural equivalents, unless the context clearly dictates otherwise.

All ations mentioned herein are incorporated herein by reference in their entirety to disclose and describe the methods and/or materials which are the subject of those publications. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present technology is not entitled to antedate such publication by virtue of prior ion. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.

The terms "comprises" and "comprising" should be interpreted as referring to ts, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or ed with other elements, components, or steps that are not expressly referenced.

The subject headings used in the detailed description are included only for the ease of reference of the reader and should not be used to limit the subject matter found throughout the disclosure or the claims. The subject headings should not be used in construing the scope of the claims or the claim limitations.

P1415NZ7 / 506176NZDIV6 Although the technology herein has been described with reference to particular examples, it is to be understood that these examples are merely illustrative of the principles and applications of the technology. In some instances, the terminology and symbols may imply specific details that are not required to practice the technology. For example, although the terms "first" and "second" may be used, unless otherwise specified, they are not intended to indicate any order but may be utilised to distinguish between distinct ts. Furthermore, although process steps in the methodologies may be described or illustrated in an order, such an ordering is not required. Those skilled in the art will recognize that such ng may be modified and/or aspects f may be conducted rently or even synchronously.

It is therefore to be understood that numerous modifications may be made to the illustrative examples and that other arrangements may be devised without departing from the spirit and scope of the technology.

P1415NZ7 / 506176NZDIV6 .9 REFERENCE SIGNS LIST 1000 Patient 1100 Bed partner 3000 Patient interface 3100 Sealing or seal-forming structure 3150 Cradle cushion module 3160 Pillows cushion module 3165 Nasal pillow 3200 Plenum chamber 3300 Positioning and stabilising structure / headgear 3301 Force from upper ns of tubes 3302 Force from strap 3303 Sealing force tension 3304 Superior tube portion 3305 First end of the superior tube portion 3306 Second end of the superior tube portion 3308 Point alongside tab 3310 Strap 3313 Split 3320 Tab 3321 Slit angle 3322 Slit 3323 Length axis of the slit 3324 Trough 3325 Point along tubes proximate strap 3326 Superior end of slit 3327 Inferior end of slit 3328 Tab surface 3329 Posterior side 3331 Superior edge of tab 3332 Inferior edge of tab 3347 Rounded edges 3348 Patient contacting side 3349 Non-patient ting side 3350 Gas delivery tubes 3352 Tube wall 3353 Path 3354 Tangent to the path 3355 Slit-adjacent portion 3362 Extendable concertina structure 3363 Non-extendable tube n 3364 Sleeve 3370 Ridge ting portions 3372 Ridge 3373 Groove 3374 Curved ridge portion 3375 ht ridge portion 3376 Curved groove portion Z7 / 506176NZDIV6 3377 Straight groove portion 3382 Interior Ridge 3383 Interior Groove 3390 Fluid tion opening 3400 Vent 3600 Connection port 3610 Elbow 4000 RPT device 4010 External housing 4012 Upper portion 4014 Lower Portion 4015 Panel 4016 Chassis 4018 Handle 4020 Pneumatic block 4100 Pneumatic components 4110 Air filter 4112 Inlet air filter 4114 Outlet air filter 4122 Inlet muffler 4124 Outlet muffler 4140 Pressure generator 4142 Controllable blower 4144 Brushless DC motor 4170 Air t 4200 Electrical components 4202 Printed Circuit Board Assembly (PCBA) 4210 Electrical power supply 4220 Input devices 4270 Transducers 5000 Humidifier 5002 Humidifier inlet 5004 Humidifier outlet 5006 Humidifier base 5110 Humidifier oir 5130 Humidifier reservoir dock 5240 Heating element P1415NZ7 / 506176NZDIV6 6

Claims (19)

1. A patient ace comprising: a plenum r pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient; a seal-forming structure constructed and ed to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways for sealed delivery of a flow of air at a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient’s respiratory cycle in use, said seal-forming structure having a hole therein such that the flow of air at said therapeutic pressure is delivered to at least an entrance to the patient’s nares, the orming structure constructed and arranged to maintain said therapeutic pressure in the plenum chamber throughout the patient’s respiratory cycle in use; a positioning and stabilising structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient’s head, the positioning and stabilising structure comprising: at least one gas ry tube to receive the flow of air from a connection port on top of the patient’s head and to deliver the flow of air to the ce of the t’s airways via the seal-forming structure, the gas delivery tube being constructed and arranged to t, in use, at least a region of the patient’s head superior to an otobasion superior of the patient’s head, the gas ry tube comprising: a tube wall defining a hollow interior through which air is able to flow to the seal-forming structure, the tube wall having an extendable portion configured to be extended to vary a length of the gas delivery tube, n the extendable portion comprises an extension stiffness within the range of 0.2 to 0.35 N/mm; and P1415NZ7 / 506176NZDIV6 a vent structure to allow a continuous flow of gases d by the patient from an interior of the plenum chamber to ambient, said vent structure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use, wherein the patient interface is configured to allow the patient to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient ace is configured to leave the patient’s mouth uncovered.

2. The patient interface of claim 1, wherein the extension stiffness of the extendable portion is within the range of 0.25 to 0.3 N/mm.

3. The patient interface of claim 1 or claim 2, wherein the pair of gas delivery tubes comprise a combined unextended length, measured along a centreline of a side of the pair of tubes configured to be patient-facing in use, within the range of 500 to 535 mm.

4. The patient interface of claim 3, wherein the combined nded length is within the range of 510 to 525 mm.

5. The patient interface of claim 3 or 4, wherein the combined unextended length is within the range of 512 to 522 mm.

6. The patient interface of claim 1 or claim 2, wherein the pair of gas delivery tubes comprise a combined unextended length, measured along a centreline of a side of the pair of tubes configured to be patient-facing in use, within the range of 460 to 500 mm.

7. The patient interface of claim 6, wherein the combined unextended length is within the range of 470 to 490 mm.

8. The patient ace of claim 7, wherein the combined nded length is within the range of 475 to 485 mm.

9. The patient ace of claim 1, n the gas delivery tubes form a loop around the patient’s head together with a n module, the loop having an unextended length measured along a centreline of a side of the gas delivery tubes and Z7 / 506176NZDIV6 cushion module ured to be patient-facing in use, the unextended length of the loop being within the range of 510 to 610 mm.

10. The patient interface of claim 9, wherein the unextended length of the loop is within the range of 528 to 548 mm.

11. The patient interface of claim 10, wherein the unextended length of the loop is within the range of 535 to 541 mm.

12. The t interface of claim 11, wherein the unextended length of the loop is within the range of 534 to 554 mm.

13. The patient interface of claim 12, wherein the unextended length of the loop is within the range of 539 to 549 mm.

14. The t interface of claim 9, wherein the unextended length of the loop is within the range of 541 to 561 mm.

15. The patient interface of claim 14, wherein the unextended length of the loop is within the range of 546 to 556 mm.

16. The patient interface of claim 9, wherein the unextended length of the loop is within the range of 564 to 584 mm.

17. The patient interface of claim 16, wherein the unextended length of the loop is within the range of 571 to 581 mm.

18. The patient interface of claim 25, wherein the unextended length of the loop is within the range of 577 to 597 mm.

19. The patient interface of claim 18, wherein the unextended length of the loop is within the range of 582 to 592 mm. 4000 5000 4170 3000 1000 1100 1000 3000 4170 5000 4000 4000 5000 4170 Nasal cavity Oral cavity Larynx Vocal folds Alveolar sacs Oesophagus Trachea Bronchus Heart Copyright 2012 ResMed Limited Nasal cavity Nasal bone Lateral nasal cartilage Greater alar age Hard palate Nostril Soft palate Lip superior Lip inferior Oropharynx Tongue Epiglottis Vocal folds Larynx Esophagus Trachea Copyright 2012 ResMed Limited Sagittal plane Superior Right Left Endocanthion Nasal ala Lip Superior Nasolabial sulcus Upper Vermillion Lower Vermillion Cheilion Lip Inferior Mouth width radially inward radially outward Copyright 2012 ResMed Limited Otobasion superior Otobasion inferior Alar crest point Sellion Subnasale Glabella Posterior Ridge Lip superior Lip Inferior Supramenton Superior Inferior Pronasale Anterior ght 2012 ResMed Limited Coronal plane Frankfort horizontal Nasolabial angle Posterior Superior or Anterior Copyright 2012 ResMed Limited Saggital plane columella Subnasale Naris Major axis of naris Upper vermillion Lip inferior Naso-labial sulcus Copyright 2012 ResMed Limited