NZ757562B2 - Patient interface - Google Patents

Abstract

seal-forming structure (3100) for a patient interface includes a patient-contacting surface (3114) configured to engage the patient's facial skin to form a seal; a posterior opening (3106) formed in the patient-contacting surface, the posterior opening configured to provide the flow of air at therapeutic pressure to the patient's nares; and a support structure (3110) extending from the patient contacting surface to an interior surface of the seal-forming structure, the support structure and the interior surface forming a continuous loop. 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 interface is configured to leave the patient's mouth uncovered. A superior and medialmost portion of the seal-forming structure is structured to engage the patient’s nose inferior to the patient’s nasal bone. apeutic pressure to the patient's nares; and a support structure (3110) extending from the patient contacting surface to an interior surface of the seal-forming structure, the support structure and the interior surface forming a continuous loop. 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 interface is configured to leave the patient's mouth uncovered. A superior and medialmost portion of the seal-forming structure is structured to engage the patient’s nose inferior to the patient’s nasal bone.

Description

James & Wells Ref: 506137NZ PATIENT ACE 1 CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 62/480,059, filed March 31, 2017, the entire contents of which are incorporated herein by reference. 2 BACKGROUND OF THE TECHNOLOGY 2.1 FIELD OF THE LOGY The present technology relates to one or more of the detection, diagnosis, treatment, prevention and amelioration of respiratory-related disorders. The present technology also relates to l devices or tus, 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 tates 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, r 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 d air into the venous blood and carbon dioxide to move in the opposite direction. The trachea divides into right and left main bronchi, which further divide eventually into terminal bronchioles. The bronchi make up the conducting 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 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 ers may be terised by particular events, e.g. apneas, hypopneas, and hyperpneas.

James & Wells Ref: 506137NZ es of respiratory disorders include Obstructive Sleep Apnea (OSA), Cheyne-Stokes Respiration (CSR), respiratory insufficiency, Obesity Hyperventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease (COPD), Neuromuscular Disease (NMD) and Chest wall disorders.

Obstructive Sleep Apnea (OSA), a form of Sleep ered Breathing (SDB), is characterised by events ing occlusion or obstruction of the upper air passage during sleep. It s from a combination of an abnormally small upper airway and the normal loss of muscle tone in the region of the tongue, soft palate and posterior oropharyngeal wall during sleep. The ion causes the affected patient to stop breathing for s typically of 30 to 120 seconds 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 er, particularly in middle aged ight 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 disorder of a patient's respiratory controller in which there are ic alternating periods of waxing and waning ation known as CSR .

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

Respiratory failure is an umbrella term for respiratory 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.

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

James & Wells Ref: NZ Obesity Hyperventilation Syndrome (OHS) is defined as the combination of severe obesity and awake chronic hypercapnia, in the e of other known causes for ntilation. Symptoms include dyspnea, morning headache and excessive daytime sleepiness. c Obstructive Pulmonary Disease (COPD) encompasses any of a group of lower airway diseases that have n characteristics in common. These include increased resistance to air movement, extended expiratory phase of respiration, and loss of the normal elasticity of the lung. Examples of COPD are emphysema and chronic bronchitis. COPD is caused by chronic tobacco smoking (primary risk factor), occupational exposures, air pollution and genetic factors.

Symptoms e: dyspnea on exertion, chronic cough and sputum production.

Neuromuscular Disease (NMD) is a broad term that encompasses 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 characterised by progressive muscular ment leading to loss of ambulation, being wheelchair-bound, swallowing difficulties, respiratory muscle weakness and, eventually, death from respiratory failure. Neuromuscular ers can be divided into y progressive and slowly progressive: (i) Rapidly progressive disorders: 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 ers); (ii) Variable or slowly progressive disorders: Characterised 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, gia, dyspnea on exertion and at rest, e, sleepiness, morning headache, and difficulties with concentration and mood changes.

Chest wall ers are a group of thoracic deformities that result in inefficient coupling n the respiratory muscles and the thoracic cage. The disorders are usually characterised by a restrictive defect and share the potential of long term hypercapnic respiratory failure. Scoliosis and/or kyphoscoliosis may cause James & Wells Ref: 506137NZ severe respiratory failure. Symptoms of respiratory e e: dyspnea on exertion, peripheral oedema, orthopnea, repeated chest infections, morning hes, fatigue, poor sleep quality and loss of appetite.

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

Furthermore, otherwise healthy individuals may take advantage of such therapies to prevent respiratory disorders from arising. r, these have a number of shortcomings. 2.2.2 Therapy Various therapies, such as Continuous Positive Airway re (CPAP) therapy, Non-invasive ventilation (NIV) and Invasive 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 ion, such as by pushing the soft palate and tongue forward and away from the posterior oropharyngeal wall. ent 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, expensive and aesthetically unappealing.

Non-invasive ventilation (NIV) provides ventilatory support to a patient through 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 ing. 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. ve ventilation (IV) provides ventilatory support to patients that are no longer able to effectively breathe themselves and may be provided using a James & Wells Ref: NZ tracheostomy tube. In some forms, the comfort and effectiveness of these therapies may be improved. 2.2.3 Treatment Systems These therapies may be ed by a treatment system or device. Such systems and devices may also be used to diagnose a condition without treating it.

A treatment system may se a Respiratory Pressure Therapy Device (RPT device), an air circuit, a humidifier, a patient ace, and data management.

Another form of treatment system is a mandibular repositioning device. 2.2.3.1 Patient Interface A patient interface may be used to interface respiratory equipment to its , for example 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 ostomy 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 variance with ambient pressure to effect therapy, e.g., at a positive re 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 tate delivery to the airways of a supply of gas at a ve pressure of about 10 cmH2O.

Certain other mask systems may be functionally unsuitable for the present field. For example, purely ntal masks may be unable to maintain a suitable pressure. Mask systems used for ater swimming or diving may be configured to guard against 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 unfavourable for the present technology e.g. if they block airflow via the nose and only allow it via the mouth.

James & Wells Ref: NZ Certain masks may be uncomfortable or impractical for the present logy if they require 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 patient interface presents a number of challenges. 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 , different regions of the face respond differently to mechanical forces. 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 g, difficult 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 t 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 ble 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 discomfort 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 effective 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 ended that a t 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 t compliance.

James & Wells Ref: 506137NZ While a mask for other applications (e.g. rs) 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 ations.

For these reasons, patient interfaces for delivery of CPAP during sleep form a distinct field. 2.2.3.1.1 Seal-forming structure t interfaces may include a seal-forming structure. Since it is in direct contact with the patient’s face, the shape and uration of the seal-forming structure can have a direct impact the effectiveness and comfort of the patient interface.

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 sub-portion to form a seal around the right naris. In one form of patient interface, a seal-forming structure may comprise a single element that surrounds 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 orming structure may se an element that surrounds a mouth region in use, e.g. by forming 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 nds both nares and a mouth region in use. These different types of patient interfaces may be known by a y 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, ure, variability and sensitivity regions of the patient’s face. For example, a seal on swimming goggles that overlays a patient’s forehead may not be appropriate to use on a patient’s nose.

James & Wells Ref: 506137NZ n seal-forming structures may be ed for mass manufacture such that one design fit and be comfortable and effective for a wide range of ent 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 structure of the mass-manufactured patient interface, one or both must adapt in order for a seal to form.

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 confronting engagement with the patient's face. The seal-forming structure may include an air or fluid filled n, or a moulded or formed surface of a resilient seal element made of an elastomer 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 periphery of the mask so as to provide a self-sealing action against the face of the patient when positive re 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 ed to achieve a seal, or the mask may leak. Furthermore, if the shape of the seal-forming ure does not match that of the patient, it may crease or buckle in use, giving rise to leaks.

Another type of seal-forming structure may comprise a friction-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.

James & Wells Ref: NZ A range of t interface seal-forming structure technologies are disclosed in the following patent applications, assigned to ResMed Limited: WO 1998/004,310; 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 ing products that incorporate nasal s: M nasal pillows mask, SWIFTTM II nasal pillows mask, SWIFTTM LT nasal pillows mask, SWIFTTM FX nasal pillows mask and MIRAGE YTM full-face mask. The following patent applications, assigned to ResMed Limited, describe examples of nasal pillows masks: International Patent Application WO2004/073,778 (describing amongst other things aspects of the ResMed Limited M nasal pillows), US Patent Application 2009/0044808 (describing amongst other things aspects of the ResMed Limited SWIFTTM LT nasal pillows); International Patent Applications (describing amongst other things aspects of the ResMed Limited MIRAGE YTM full-face mask); International Patent Application WO 52,560 (describing amongst other 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 pressure therapy is subject to the corresponding force of the air pressure to disrupt a seal. Thus a variety of techniques have been used to position the seal-forming ure, and to maintain it in sealing on with the appropriate portion 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.

James & Wells Ref: 506137NZ Another technique is the use of one or more straps and/or stabilising harnesses. Many such harnesses suffer from being one or more of ill-fitting, bulky, uncomfortable and awkward to use. 2.2.3.2 Respiratory Pressure Therapy (RPT) Device A atory re therapy (RPT) device may be used to deliver one or more of a number of therapies described above, such as by generating a flow of air for delivery to an entrance 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. rial-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 devices. In addition, even devices designed for medical treatment may suffer from shortcomings, pertaining to one or more of: t, noise, ease of use, cy, size, weight, manufacturability, cost, and reliability.

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

Table of noise output levels of prior RPT devices (one specimen only, measured using test method specified in ISO 3744 in CPAP mode at 10 cmH2O).

RPT Device name A-weighted sound Year (approx.) pressure level dB(A) C-Series TangoTM 31.9 2007 C-Series TangoTM with Humidifier 33.1 2007 S8 TM II 30.5 2005 S8 EscapeTM II with H4iTM Humidifier 31.1 2005 S9 AutoSetTM 26.5 2010 S9 AutoSetTM with H5i Humidifier 28.6 2010 James & Wells Ref: 506137NZ One known RPT device used for ng sleep ered breathing is the S9 Sleep Therapy System, manufactured by ResMed Limited. Another example of an RPT device is a ventilator. Ventilators such as the ResMed Stellar™ Series of Adult and Paediatric ators may provide support for invasive and non-invasive nondependent ventilation for a range of patients for treating a number of conditions such as but not limited to NMD, OHS and COPD.

The ResMed Elisée™ 150 ventilator and ResMed VS III™ ventilator may provide support for invasive and non-invasive dependent ventilation suitable for adult or paediatric patients for treating a number of conditions. These ators provide tric and barometric ation modes with a single or double limb circuit.

RPT devices typically comprise a pressure generator, such as a motor-driven blower or a compressed gas reservoir, and are configured to supply a flow of air to the airway of a patient. In some cases, the flow of air may be supplied to the airway of the patient at positive pressure. The outlet of the RPT device is connected via an air circuit to a patient interface such as those described above.

The designer of a device may be presented with an infinite number of choices to make. Design criteria often conflict, meaning that certain design choices are far from routine or inevitable. Furthermore, the comfort and efficacy of certain aspects may be highly sensitive to small, subtle changes in one or more parameters. 2.2.3.3 fier Delivery of a flow of air without humidification may cause drying of airways. The use of a humidifier with an RPT device and the patient interface produces fied gas that minimizes drying of the nasal mucosa and increases patient airway comfort. In addition 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, r they may not fulfil the specialised requirements of a medical humidifier. l humidifiers are used to increase humidity and/or temperature of the flow of air in relation to ambient air when required, typically where the patient James & Wells Ref: 506137NZ may be asleep or g (e.g. at a hospital). A medical humidifier for bedside ent may be small. A medical humidifier may be configured to only humidify 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, r those systems would also humidify and/or heat the entire room, which may cause discomfort to the occupants. Furthermore medical humidifiers may have more ent safety constraints than industrial humidifiers While a number of medical humidifiers are known, they can suffer from one or more shortcomings. Some medical 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 "compliant", e.g. that the patient has used their RPT device according to certain a "compliance rule". One example of a ance rule for CPAP therapy is that a t, 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 patient's compliance, a provider of the RPT , such as a health care provider, may ly obtain data describing the patient's therapy using the RPT device, calculate the usage over a predetermined time , and compare with the ance rule. Once the health care provider has determined that the patient has used their RPT device according to the ance 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.

James & Wells Ref: 506137NZ 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 adjustable oral nce available from a dentist or other supplier that holds the lower jaw (mandible) in a d 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 , puts tension on the geal walls to reduce se 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 intended to engage with or fit over teeth on the upper jaw or mandible. The upper and lower splints are connected together laterally via a pair of connecting rods. The pair of connecting rods are fixed symmetrically 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 advanced position. The length of the connecting rods may be ed to change the level of protrusion of the mandible. A t may determine a level of protrusion for the mandible that will determine the length of the connecting rods.

Some MRDs are structured to push the mandible forward relative to the maxilla while other MADs, 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.

James & Wells Ref: 506137NZ 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 r, 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 thus provide insufficient washout. Some vents may be disruptive of the sleep of a bed partner 1100 of the patient 1000, e.g. h noise or focussed airflow.

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

International Patent ation 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 re at Mask name Mask type A-weighted A-weighted Year (approx.) sound power sound re level dB(A) dB(A) (uncertainty) (uncertainty) Glue-on (*) nasal 50.9 42.9 1981 ResCare nasal 31.5 23.5 1993 standard (*) 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 James & Wells Ref: 506137NZ ResMed nasal 29 (3) 22 (3) 2008 MirageTM SoftGel ResMed nasal 26 (3) 18 (3) 2010 MirageTM FX ResMed nasal pillows 37 29 2004 Mirage SwiftTM ResMed nasal pillows 28 (3) 20 (3) 2005 Mirage SwiftTM 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 Conversational speech 60 1m distance Average home 50 Quiet library 40 Quiet bedroom at night 30 Background in TV studio 20 2.2.4 Diagnosis and Monitoring Systems mnography (PSG) is a conventional system for diagnosis and monitoring of cardio-pulmonary disorders, and typically es expert clinical staff to apply the system. PSG typically involves the placement of 15 to 20 t sensors James & Wells Ref: 506137NZ on a patient in order to record s bodily signals such as electroencephalography (EEG), electrocardiography (ECG), electrooculograpy (EOG), electromyography (EMG), etc. PSG for sleep disordered ing has involved two nights of observation of a patient in a clinic, one night of pure diagnosis and a second night of titration of ent parameters by a clinician. PSG is therefore expensive and inconvenient. In particular it is unsuitable for home sleep g.

Clinical experts may be able to diagnose or monitor patients adequately based on visual observation of PSG signals. However, there are stances 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 al expert may apply a different standard at different times. 3 BRIEF SUMMARY OF THE TECHNOLOGY The present technology is directed towards providing l devices used in the diagnosis, ration, treatment, or prevention of respiratory disorders having one or more of improved comfort, cost, efficacy, ease of use and manufacturability.

A first aspect of the present technology relates to apparatus used in the diagnosis, amelioration, treatment or prevention of a respiratory disorder.

Another aspect of the present technology relates to methods used in the sis, amelioration, treatment or prevention 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.

An aspect of the present technology is ed to a seal-forming structure for a patient interface that is configured to form a seal with the patient’s nares and the seal-forming structure comprises a t structure forming a continuous loop with an interior surface of the seal-forming structure, the loop structure supporting a superior portion of a patient contacting surface of the orming structure, and the James & Wells Ref: 506137NZ superior portion of the patient contacting surface having a single layer that is not supported by an undercushion.

An aspect of the present logy is ed to a patient interface that comprises: a plenum chamber pressurisable to a eutic 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 arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways, the seal-forming structure constructed and arranged to maintain said eutic re in the plenum chamber throughout the patient’s respiratory cycle in use; a positioning and stabilising ure to provide a force to hold the sealforming structure in a therapeutically effective position on the patient’s head, the positioning and ising structure comprising a tie, the tie being constructed and arranged so that at least a portion overlies a region of the patient’s head superior to an otobasion superior of the t’s head in use; and a vent structure to allow a continuous flow of gases d by the t 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 ured 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 interface is configured to leave the patient’s mouth uncovered, wherein the seal-forming structure further comprises a patient-contacting surface configured to engage the patient’s facial skin to form a seal and a posterior opening formed in the patient-contacting surface, the posterior opening configured to provide the flow of air at said eutic pressure to the patient’s nares, and n the seal-forming structure includes a support structure extending from a first location on the t contacting surface to a second location on an interior surface of the seal-forming structure, the support structure and the interior surface forming a continuous loop.

In examples, (a) the seal-forming structure may comprise an anterior opening formed in a non-patient contacting surface and an anterior tie that spans the anterior opening, and a first end of the support structure may be connected to the James & Wells Ref: 506137NZ anterior tie, (b) the seal-forming structure may comprise an edge ng the posterior opening in the patient contacting surface, and a second end of the support ure may be connected to the t contacting surface at a superior region of the edge, (c) the seal-forming ure may comprise an undercushion that supports the patient contacting surface, (d) an inferior n of the seal-forming structure may include the undercushion and a superior portion of the seal-forming structure may not include the undercushion, (e) the support structure may have a length in an undeformed state that is greater than a linear ce from the first location to the second location, (f) the support structure may be configured to be positioned adjacent to or in contact with the patient’s columella during use, (g) the support ure may be curved along a longitudinal axis of the support structure in an undeformed state, (h) the support structure may have a different thickness than the patient-contacting surface, (i) the support structure may be thicker than the patient-contacting surface, (j) the support structure may not extend completely across the posterior opening, (k) the seal-forming structure may at least partly form a gas chamber, and in an undeformed state the support structure may s into the gas chamber, (l) the support structure may have a variable ess in a longitudinal direction, (n) the support structure may have an increased thickness adjacent the first location and/or the second location, (n) a portion of the support structure may be curved away from the patient’s nose along a longitudinal axis of the support structure in an undeformed state, and/or (o) the undercushion may be structured to only support the patient contacting surface against the patient’s lip superior.

An aspect of the present technology is directed to a seal-forming ure for a patient interface, the seal-forming structure ucted and arranged to form a seal with a region of the patient’s face surrounding an entrance to the t’s airways, the seal-forming structure constructed and arranged to maintain a therapeutic pressure of at least 6 cmH2O above ambient air pressure in a plenum chamber hout the patient’s respiratory cycle in use. The seal-forming structure comprises: a patient-contacting surface configured to engage the patient’s facial skin to form a seal; a posterior opening formed in the patient-contacting surface, the ior opening configured to provide the flow of air at said eutic pressure to the patient’s nares; and a support structure ing from a first location on the James & Wells Ref: 506137NZ patient contacting surface to a second location on an interior surface of the sealforming structure, the support structure and the interior surface forming a continuous loop, wherein the patient interface is ured to allow the patient to breath from ambient through their mouth in the absence of a flow of rised air through the plenum r inlet port, or the patient interface is configured to leave the patient’s mouth uncovered.

In es, (a) the seal-forming structure may comprise an or opening formed in a non-patient contacting surface and an anterior tie that spans the or opening, and a first end of the support structure may be connected to the anterior tie, (b) the seal-forming structure may se an edge bounding the posterior opening in the patient contacting e, and a second end of the support ure may be connected to the patient contacting surface at a superior region of the edge, (c) the seal-forming structure may comprise an undercushion that supports the patient contacting surface, (d) an inferior portion of the seal-forming structure may include the undercushion and a superior portion of the seal-forming structure may not include the undercushion, (e) the support structure may have a length in an undeformed state that is greater than a linear distance from the first location to the second on, (f) the support structure may be configured to be positioned adjacent to or in contact with the t’s columella during use, (g) the support structure may be curved along a longitudinal axis of the support structure in an rmed state, (h) the support structure may have a different thickness than the patient-contacting surface, (i) the support structure may be thicker than the patient-contacting e, (j) the support structure may not extend completely across the posterior opening, (k) the seal-forming structure may at least partly form a gas chamber, and in an undeformed state the support ure may extends into the gas chamber, (l) the support structure may have a variable thickness in a longitudinal direction, (n) the support structure may have an increased thickness adjacent the first location and/or the second location, (n) a portion of the support structure may be curved away from the patient’s nose along a longitudinal axis of the support structure in an undeformed state, and/or (o) the undercushion may be structured to only support the patient contacting surface against the patient’s lip superior.

James & Wells Ref: 506137NZ An aspect of the present technology is directed to a patient ace that comprises: a plenum r risable 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 arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways, the seal-forming 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 ure to provide a force to hold the rming structure in a therapeutically ive position on the patient’s head, the positioning and stabilising structure sing a tie, the tie being constructed and arranged so that at least a portion overlies a region of the patient’s head superior to an ion superior of the patient’s head in use; a decoupling structure; and a vent ure to allow a continuous flow of gases exhaled by the patient from an interior of the plenum r 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 interface is configured to leave the patient’s mouth uncovered, and wherein vent structure further comprises gs through the decoupling structure and openings through the plenum chamber.

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

An aspect of one form of the present technology is a method of manufacturing tus.

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 experience in using this type of medical device.

James & Wells Ref: 506137NZ 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 equipment. An aspect of one form of the present technology is a humidifier tank that may be washed in a home of a patient, e.g., in soapy water, without requiring lised cleaning equipment.

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

Other features of the technology will be apparent from consideration of the information contained in the following detailed description, abstract, drawings and claims. 4 BRIEF DESCRIPTION OF THE DRAWINGS The present technology is rated by way of example, and not by way of tion, in the figures of the accompanying drawings, in which like nce numerals refer to similar elements including: 4.1 TREATMENT SYSTEMS Fig. 1A shows a system including a patient 1000 wearing a patient ace 3000, in the form of nasal pillows, ing a supply of air at positive re from an RPT device 4000. Air from the RPT device 4000 is fied 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 position.

Fig. 1B shows a system including a patient 1000 wearing 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 fied 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 James & Wells Ref: 506137NZ 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. The patient is sleeping in a side sleeping position. 4.2 RESPIRATORY SYSTEM AND FACIAL ANATOMY Fig. 2A shows an overview of a human respiratory system including the nasal and oral es, the , vocal folds, oesophagus, trachea, us, lung, alveolar sacs, heart and agm.

Fig. 2B shows a view of a human upper airway including the nasal cavity, nasal bone, lateral nasal age, greater alar age, nostril, lip superior, lip inferior, , hard palate, soft palate, oropharynx, tongue, epiglottis, vocal folds, oesophagus and trachea.

Fig. 2C is a front view of a face with several features of surface anatomy fied 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 radially outward.

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

Also indicated 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 midsagittal plane.

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

James & Wells Ref: 506137NZ Fig. 2H shows subcutaneal structures of the nose, including lateral age, septum cartilage, greater alar cartilage, lesser alar cartilage, sesamoid age, nasal bone, epidermis, adipose tissue, frontal process of the a and fibrofatty tissue.

Fig. 2I shows a medial dissection of a nose, approximately several millimeters from the ittal plane, amongst other things showing the septum age 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 indicated, as are the maxilla, and mandible.

Fig. 2K shows a lateral view of a skull with the outline of the surface of a head, as well as several s. The following bones are shown: frontal, 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 ace 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 structure at a point. An outward normal at the point is ted. 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 cross-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 magnitude when compared to the magnitude of the curvature shown in Fig. 3B.

James & Wells Ref: 506137NZ 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 d normal at the point is indicated. The ure at the point has a negative sign, and a relatively small magnitude when ed 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 ted. The curvature at the point has a negative sign, and a relatively large magnitude when compared to the magnitude of the curvature shown in Fig. 3E.

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 or surface of the cushion is indicated. An edge of the surface is indicated. A path on the surface between points A and B is indicated. A straight line distance between A and B is indicated. Two saddle regions and a dome region are ted.

Fig. 3I shows the surface of a structure, with a one dimensional hole in the e. 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 ure of Fig. 3I, including the two dimensional hole and the one dimensional 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 bladder as a cushion.

James & Wells Ref: 506137NZ 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 ional hole in the mask.

Fig. 3N shows a further cross-section h the mask of Fig. 3L. The interior surface 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.

Fig. 3T shows a view of a mask, including the sign of the torsion of the space curve defined by the edge of the sealing membrane in different regions of the mask.

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

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

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

Fig. 3W shows a cross-section through the plenum chamber of Fig. 3V, the cross-section being taken at the sagittal 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 3210 which lies on the al plane and just touches the cushion of the plenum chamber at two points on the sagittal plane: a superior point 3220 and an inferior point 3230.

Depending on the geometry of the cushion in this region, the ntact plane may be a tangent at both the or and inferior points.

James & Wells Ref: 506137NZ 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 des 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 3220 sits approximately on the sellion, while the inferior point 3230 sits on the lip superior. 4.4 RPT DEVICE Fig. 4A shows an RPT device in ance with one form of the t technology.

Fig. 4B is a schematic diagram of the pneumatic path of an RPT device in accordance with one form of the present technology. The directions of am and downstream are indicated with nce to the blower and the patient interface. The blower is defined to be upstream of the patient interface and the patient interface is defined to be downstream of the blower, regardless of the actual flow direction at any particular . 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 HUMIDIFIER Fig. 5A shows an isometric view of a humidifier in ance with one form of the present technology.

Fig. 5B shows an isometric view of a humidifier in accordance with one form of the present technology, showing a humidifier reservoir 5110 removed from the humidifier reservoir dock 5130. 4.6 BREATHING WAVEFORMS Fig. 6 shows a model typical breath waveform of a person while sleeping.

James & Wells Ref: 506137NZ 4.7 PATIENT INTERFACE ACCORDING TO THE PRESENT TECHNOLOGY depicts an or perspective view of a seal-forming structure of a t interface according to an example of the present technology. depicts an anterior view of a seal-forming structure of a patient interface according to an example of the present technology. depicts a lateral view of a seal-forming structure of a patient interface ing to an example of the present technology. s a posterior view of a seal-forming structure of a patient interface according to an example of the t technology. depicts an inferior view of a seal-forming structure of a patient interface according to an example of the present technology. depicts a superior view of a seal-forming ure of a patient ace ing to an example of the present technology. depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7G-7G of according to an example of the present technology. depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7H-7H of according to an example of the present technology. depicts a cross-sectional view of a seal-forming ure of a patient interface taken through line 7I-7I of according to an example of the present technology. depicts a cross-sectional view of a seal-forming structure of a patient interface taken h line 7J-7J of according to an e of the present technology.

James & Wells Ref: 506137NZ depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7K-7K of according to an example of the present technology. depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7L-7L of according to an example of the present technology. depicts a sectional view of a orming structure of a patient interface taken through line 7M-7M of according to an example of the t technology. depicts a posterior perspective view of a decoupling structure of a patient interface according to an example of the present technology. depicts an anterior perspective view of a ling structure of a patient ace according to an e of the t technology. depicts a posterior perspective view of a decoupling structure of a patient interface according to an example of the present technology. depicts an anterior ctive view of a decoupling structure of a patient interface according to an example of the t technology.

A depicts a superior perspective view of a patient ace according to an example of the present technology.

B depicts an anterior perspective view of a patient interface according to an example of the present technology.

DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY Before the present technology is described in further detail, 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 tood that the terminology used in this James & Wells Ref: 506137NZ disclosure is for the purpose of describing only the particular examples discussed , and is not intended to be limiting.

The following description is provided in relation to various es which may share one or more common characteristics and/or features. It is to be understood that one or more features of any one example may be combinable with one or more features of another example or other examples. In addition, any single feature or combination of features in any of the examples may constitute a further example. .1 THERAPY In one form, the present technology comprises a method for treating a respiratory disorder comprising the step of applying positive pressure to the entrance of the airways of a patient 1000.

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

In certain es of the present technology, mouth breathing is limited, restricted or prevented. .2 TREATMENT SYSTEMS In one form, the present logy 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. .3 T INTERFACE 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 oning and stabilising structure 3300, a vent 3400, one form of connection port 3600 for connection to air circuit 4170, and a ad support 3700. In some forms a functional aspect may be ed by one or more physical ents. In some forms, one physical component may provide one James & Wells Ref: 506137NZ 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.

If a patient interface 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 ace 3000 in accordance with one form of the present technology is constructed and arranged to be able to e a supply of air at a positive pressure of at least 6 cmH2O with t to ambient.

The t ace 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 10 cmH2O with respect to ambient.

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 20 cmH2O with respect to ambient. .3.1 Seal-forming ure In one form of the present technology, a seal-forming structure 3100 provides a target seal-forming region, and may additionally provide a cushioning function. The target seal-forming region is a region on the seal-forming 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 patient to patient, depending on a range of factors including for example, where the patient interface was placed on the face, tension in the positioning and stabilising structure and the shape of a t’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.

James & Wells Ref: 506137NZ A orming structure 3100 in ance with the present technology may be ucted from a soft, flexible, resilient material such as silicone.

In certain forms of the present technology, a system is ed comprising more than one a seal-forming structure 3100, each being configured to correspond to a different size and/or shape range. For e the system may comprise one form of a seal-forming structure 3100 suitable for a large sized head, but not a small sized head and another le for a small sized head, but not a large sized head. .3.1.1 Sealing mechanisms In one form, the seal-forming structure includes a sealing flange utilizing a pressure assisted 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 t 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 s around the perimeter of the plenum chamber 3200. Support flange may be relatively thicker than the sealing . 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 functions to support the sealing flange from buckling in use.

In one form, the seal-forming structure may comprise a compression g portion or a gasket sealing portion. In use the compression sealing portion, 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.

James & Wells Ref: 506137NZ In one form, the seal-forming ure comprises a tension portion. In use, the tension portion is held in tension, e.g. by adjacent regions of the sealing flange.

In one form, the seal-forming structure comprises a region having a tacky or adhesive surface.

In n forms of the present technology, a seal-forming structure may comprise one or more of a pressure-assisted sealing flange, a compression sealing portion, a gasket sealing n, a tension portion, and a portion having a tacky or adhesive surface. .3.1.2 Nose bridge or nose ridge region In one form, the non-invasive 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 patient'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 rming 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 rming structure that forms a seal in use on a chin-region of the patient's face.

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

James & Wells Ref: 506137NZ .3.1.5 Forehead region In one form, the seal-forming structure that forms a seal in use on a forehead region of the patient's face. In such a form, the plenum chamber may cover the eyes in use. .3.1.6 Nasal pillows In one form the seal-forming structure of the non-invasive patient interface 3000 ses a pair of nasal puffs, or nasal pillows, each nasal puff or nasal pillow being constructed and arranged to form a seal with a respective naris of the nose of a patient.

Nasal pillows in accordance with an aspect of the present technology include: 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 ide of the frusto-cone and connecting the frusto-cone to the stalk. In addition, the structure to which the nasal pillow of the t technology is ted includes a flexible region adjacent the base of the stalk. The flexible s can act in concert to facilitate a universal joint structure that is accommodating of ve nt 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 axially displaced towards the structure to which the stalk is connected. 7 Seal-Forming Structure With Support Structure FIGS. 7A to 7M depict a seal-forming structure 3100 according to an example of the present technology. The seal-forming structure 3100 may be characterized as a nasal cradle cushion. The seal-forming structure 3100 may be structured to seal with the patient’s face around the patient’s nares to provide the pressurized, breathable air to the patient’s nasal airways while not ng the patient’s mouth.

An inferior portion of the seal-forming structure 3100 may engage the patient’s lip superior to form a seal, and the seal-forming structure 3100 may not extend beyond the lip superior to the patient’s upper vermilion. In an example, a James & Wells Ref: 506137NZ superior portion of the orming structure 3100 may be structured to engage the patient’s nose inferior to the patient’s nasal bone to form a seal. In another example, a superior portion of the seal-forming structure 3100 may be structured to engage the patient’s nose inferior to the patient’s pronasale to form a seal. Lateral portions of the seal-forming structure 3100 may be structured to engage the patient’s face n the patient’s nasal alar and the patient’s cheeks to form a seal. The lateral portions of the seal-forming structure 3100 may be structured to extend beyond the alar crest point to engage the patient’s face and form a seal.

The seal-forming structure 3100 according to the present technology may include attributes of nasal cradle cushions disclosed in International Application ation Nos. filed November 14, 2014, each of which is incorporated herein by reference in its entirety.

The seal-forming structure 3100 according to the example depicted in FIGS. 7A to 7M includes a connection region 3102 at an anterior side thereof. The connection region 3102 is structured to t the seal-forming structure 3100 to the plenum chamber 3200. The connection region 3102 provides an interface for engagement with the plenum chamber 3102. The connection region 3102 may connect with the plenum chamber 3200 via a ical connection such as a on fit, a snap fit, or a mechanical interlock of corresponding overhanging portions. The connection region 3102 may provide a removable tion to the plenum r 3200. The removable connection allows the seal-forming structure 3100 to be removed for ng or replacement.

The connection region 3102 of this example surrounds an anterior opening 3104 or hole. The anterior opening 3104 may be in fluid communication with the plenum chamber 3200 to receive the flow of pressurized, breathable gas and exhaled gas from the patient may pass through the anterior opening 3104 to the plenum chamber 3200 to be exhausted by the vent 3400. The anterior opening 3104 in this example is also d by an anterior tie 3108 that spans the anterior opening 3104 in James & Wells Ref: 506137NZ a superior-inferior direction between an inferior n of the connection region 3102 and a or portion of the connection region 3102.

The seal-forming structure 3100 of this example also includes a nonpatient contacting surface 3116 surrounding the connection region 3102. The non- patient contacting surface 3116 faces away from the patient’s face and does not contact the patient’s face in use. The non-patient contacting surface 3116 may also at least partly contact the plenum chamber 3200.

The seal-forming ure 3100 of this e also includes a patientcontacting e 3114. The t-contacting surface 3114 faces the patient’s face in use. The patient-contacting surface 3114 may at least partially seal against the patient’s facial skin in use. The patient-contacting surface 3114 is arranged such that the patient’s facial skin contacts the patient-contacting surface 3114 in use. The patient’s facial skin may contact only parts of the patient-contacting surface 3114 or the patient’s facial skin may contact all of the patient-contacting surface 3114 in use.

The patient-contacting e 3114 may be adjacent to the non-patient ting surface 3116. The patient-contacting surface 3114 may also be contiguous with the non-patient contacting surface 3116.

The seal-forming structure 3100 of this example also includes a gas chamber 3120 bounded at least partially by an interior surface 3112 of the sealforming structure 3100. The gas chamber 3120 may be pressurized up to 30 cmH2O by the rized, breathable gas received from the plenum chamber 3200 during As can be seen in the ior view of Fig. 7D, a posterior opening 3106 or hole is formed in the patient-contacting surface 3114. rized, breathable gas in the gas chamber 3120 of the seal-forming structure 3100 is communicated to the patient’s nares through the posterior opening 3106. Gas exhaled from the patient’s nares is communicated through the posterior opening 3106 to the gas chamber 3120 to be ted via the vent 3400. The posterior opening 3106 may be a single opening formed in the patient-contacting surface 3114 or the posterior opening 3106 may be divided into two separate openings that each communicates with a corresponding James & Wells Ref: 506137NZ naris of the patient. The posterior opening 3106 may be bounded by an edge 3118 of the t-contacting surface 3114.

The seal-forming ure 3100 of this example also includes a support structure 3110 that can be seen in FIGS. 7C, 7J, and 7M. The t structure 3110 is connected to the anterior tie 3108 at one end, and the connection is with the surface of the anterior tie 3108 that faces the or of the gas chamber 3120 or faces in a posterior direction relative to the seal-forming structure 3100. The other end of the support structure 3110 is connected to the patient-contacting e 3114 at the edge 3118. As can be seen in the cross-sectional views of FIGS. 7G to 7K and 7M, a superior portion of the patient-contacting surface 3114 of the seal-forming structure 3100 is not supported by an undercushion. The patient-contacting surface 3114 of the seal-forming structure 3100 may be a single layer that engages the patient’s nose ate to the pronasale. The single layer of the seal-forming ure 3100 in this region may be more flexible as compared to a dual-wall ement, i.e., an arrangement with an undercushion, which may provide a more comfortable and effective seal for a wider range of nose . However, such a single layer arrangement may be more prone to blowout, e.g., where the pressurized, breathable gas causes the patient-contacting surface 3114 of the seal-forming structure 3100 to disengage from the patient’s nose. The support structure 3110 counteracts this effect by tying the edge 3118 of the patient-contacting surface 3114 to another portion of the seal-forming structure 3100.

The support structure 3110 may be adjacent to or partially contact the patient’s columella to t the patient’s nose from protruding into the gas chamber 3120 of the orming structure 3100. Depending on the size and shape of an individual patient’s nose, the support structure 3110 may be near but not in direct contact with the patient’s columella. The support structure 3110 may also support the patient-contacting surface 3114 and urge the patient-contacting surface 3114 into engagement with the patient’s nose proximate to the pronasale to ensure effective sealing. , for example, also shows that the support structure 3110 does not span the posterior g 3106 and does not extend between a superior portion and an inferior portion of the edge 3118.

James & Wells Ref: 506137NZ The support ure 3110 may have a different thickness than the patient-contacting surface 3114. The support structure 3110 may be thicker than the patient-contacting surface 3114. The support structure 3110 may have a variable thickness in a longitudinal direction. The t structure 3110 may have an increased thickness adjacent the one or both of the locations at which the support structure 3110 is joined to the seal-forming ure 3100.

The support structure 3110 may, along with the interior surface 3112 and the anterior tie 3108 of the seal-forming structure 3100, form a continuous loop, as can be seen in . In an alternative example, the t ure 3110 may be connected to the interior surface 3112 of the seal-forming structure 3100 and not to the anterior tie 3108. In such an ative example, the anterior tie 3108 may be omitted. The support ure 3110 may have a length in an undeformed state that is greater than a linear distance from the two locations at which the support structure 3110 connects to the seal-forming structure 3110 to provide a degree of slack in the support structure. also shows that the support structure 3110 is curved ly inward into the gas chamber 3120 in an undeformed state. This ure may allow the support structure 3110 to better accommodate the patient’s nose, including the pronasale. atively, the support structure 3110 may be straight in an undeformed state of another example. Additionally, shows that the patient-contacting e 3114 is contiguous with an external or posterior surface of the support structure 3110. In an alternative example, the support ure 3110 may be connected to the interior surface 3112 of the seal-forming structure 3100 opposite the patient-contacting surface 3114 such that the edge 3118 separates the patientcontacting surface 3114 and the support structure 3110.

The seal-forming structure 3100, particularly the support structure 3110, may include attributes of the tie 3110 disclosed by International Application Publication No. by reference in its entirety.

James & Wells Ref: 506137NZ The seal-forming structure 3100 may also include an undercushion 3122 that ts a portion of the patient-contacting surface 3114, as can be seen in FIGS. 7G to 7M. The undercushion 3122 may only support an inferior portion of the undercushion 3122. The undercushion 3122 may be provided to only the lower half of the seal-forming structure 3100. The undercushion 3122 of these examples may be configured to support the patient-contacting e 3114 against the patient’s lip superior to ensure an ive seal. A similar undercushion layer 3105 is disclosed by U.S. Provisional Application No. 62/328,988, filed April 28, 2016, which is incorporated herein by reference in its entirety.

The connection region 3102 of the seal-forming structure 3100 may have a shape that resembles an infinity loop (∞) or the number eight (8). It may also be described as having an "hour-glass" shape. The connection region 3102 may be shaped such that its narrowest point is at the line of the seal-forming structure 3100. The connection region 3102 may then widen in the superior-inferior direction in either lateral ion away from the centreline, e.g., as shown in . .3.2 Plenum chamber The plenum chamber 3200 has a ter 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 chamber 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 n forms of the present technology, the plenum chamber 3200 does not cover the eyes of the t 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.

James & Wells Ref: 506137NZ 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 obtrusiveness of the patient interface, and help improve compliance with therapy. The use of a transparent al can aid a ian to observe how the patient interface is located and functioning.

In certain forms of the present technology, the plenum chamber 3200 is constructed from a translucent material. The use of a translucent al can reduce the obtrusiveness of the patient ace, and help e compliance with therapy. .3.3 Positioning and stabilising structure The orming structure 3100 of the patient interface 3000 of the present technology may be held in sealing position in use by the positioning and ising structure 3300.

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

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

In one form the positioning and stabilising structure 3300 provides a ion 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 interference 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 t while sleeping. In one example the positioning and stabilising structure 3300 has a low profile, or cross-sectional thickness, to reduce the perceived or actual bulk of the apparatus. In one example, the positioning and stabilising structure 3300 James & Wells Ref: 506137NZ comprises at least one strap having a rectangular section. In one example the positioning and stabilising structure 3300 comprises at least one flat strap.

In one form of the present technology, a oning and stabilising ure 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 t’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 positioning and stabilising structure 3300 is provided with a decoupling portion located between an anterior 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 patient lies with their head on a pillow, the presence of the decoupling portion prevents a force on the posterior portion from being transmitted along the positioning and stabilising structure 3300 and disrupting the seal.

In one form of the t technology, a positioning and stabilising structure 3300 comprises a strap constructed from a laminate of a fabric patientcontacting 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. In one form, the fabric outer layer comprises loop material to engage with a hook material portion.

In certain forms of the present technology, a positioning and ising structure 3300 comprises a strap that is extensible, e.g. ently extensible. For example the strap may be configured in use to be in tension, and to direct a force to draw a seal-forming ure into sealing t with a portion of a patient’s face. In an example the strap may be configured as a tie.

James & Wells Ref: 506137NZ In one form of the present logy, the positioning 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 portion of the parietal bone without overlaying the tal bone.

In one form of the present technology suitable for a nasal-only mask or for a full-face mask, the positioning and stabilising structure includes a second tie, the second tie being ucted 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.

In one form of the present logy suitable for a nasal-only mask or for a full-face mask, the positioning and stabilising structure includes a third tie that is constructed and arranged to interconnect the first tie and the second tie to reduce a tendency of the first tie and the second tie to move apart from one another.

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.

In certain forms of the present technology, a positioning and stabilising structure 3300 comprises a strap constructed to be breathable to allow moisture vapour to be transmitted h the strap, In certain forms of the present technology, a system is ed sing 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 stabilizing structure 3300 suitable for a large sized head, but not a small sized head, and r. suitable for a small sized head, but not a large sized head.

James & Wells Ref: 506137NZ .3.4 Vent In one form, the patient interface 3000 includes a vent 3400 constructed and arranged to allow for the t 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 r 3200 to ambient whilst the pressure within the plenum chamber is positive with respect to ambient. The vent 3400 is configured 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.

One form of vent 3400 in accordance with the present logy ses 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 d in a ling structure, e.g., a swivel.

The vent 3400 provided to the plenum chamber 3200 may include a plurality of openings 3402. The openings 3402 may be arranged in two groups that are symmetrical relative to the centreline of the plenum chamber 3200. The ity of openings 3402 may reduce noise and diffuse the vent flow concentration.

The openings 3402 may be located sufficiently close to the centreline of the plenum chamber 3200 such that the openings 3402 are not blocked when the patient is sleeping on their side. To avoid weakening the chassis at a relatively narrow portion, the openings 3402 may be spaced from the centreline.

The openings 3402 may have a circular profile. .3.5 Decoupling structure(s) In one form the patient interface 3000 includes at least one decoupling structure 3500, for example, a swivel or a ball and socket. FIGS. 8A, 8B, 9A, and 9B depict examples of decoupling structures 3500 ing to es of the present technology. The decoupling structures 3500 may be in the form of an elbow. The James & Wells Ref: NZ decoupling structures 3500 may include a swivel 3501 that connects to the air t 4170 and a patient interface connector 3502 that connects to the t interface 3000. The patient interface connector 3502 may permit the tube 3503 of the decoupling structure 3500 to rotate relative to the patient interface 3500. The decoupling structure 3500 may also e a vent 3400. The vent 3400 of the decoupling structure 3500 may e at least one opening 3401 through a portion of the tube 3503 and/or through a portion of the patient interface connector 3502. .3.6 Connection port Connection port 3600 allows for connection to the air t 4170. .3.7 Forehead support In one form, the patient interface 3000 includes a ad support 3700. .3.8 Anti-asphyxia valve In one form, the patient interface 3000 includes an anti-asphyxia valve. .3.9 Ports In one form of the present technology, a patient interface 3000 includes 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. .3.10 Patient Interface of the Present Technology FIGS. 10 and 11 depict a patient interface 3000 according to an example of the present technology. The patient interface 3000 includes the orming structure 3100 according to the examples described in section 4.3.1 above. The sealforming structure 3100 may be connected to the plenum chamber 3200 as described above as well. The plenum chamber 3200 may be provided with one or more vents 3400.

James & Wells Ref: NZ The patient interface 3000 may include a positioning and stabilising structure 3300 that includes ts 3301. The ts 3301 serve two purposes: 1) to position and stabilize the patient interface 3000 on the patient’s head in a therapeutically ive position during use and 2) to provide the pressurized, breathable gas to the plenum chamber 3200. As such, the conduits 3301 may be constructed of a flexible, biocompatible material and may also form a hollow structure. The conduits 3301 may be connected to the plenum chamber 3200 with clips 3303 to provide a pneumatic connection therebetween. The conduits 3301 may also include strap connectors 3302 to connect to a strap (not shown) that passes behind the patient’s head in use. The conduits 3301 may also include flexible portions 3304 that e flexibility to the conduits 3301 to accommodate different sizes and shapes of patient heads. An elbow connector 3305 .4 RPT DEVICE An RPT device 4000 in accordance with one aspect of the present technology comprises mechanical, pneumatic, and/or electrical components and is configured to execute one or more algorithms . The RPT device 4000 may be configured to generate a flow of air for delivery to a t’s airways, such as to treat one or more of the respiratory conditions described elsewhere in the t document.

In one form, the RPT device 4000 is constructed and arranged to be e 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.

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 ents of the RPT device 4000.

The RPT device 4000 may include a handle 4018.

James & Wells Ref: 506137NZ 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 d 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 l controller , a y device controller , a pressure generator 4140, one or more protection circuits , memory , transducers 4270, data ication interface and one or more output devices . Electrical components 4200 may be mounted 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 & pneumatic components An RPT device may comprise one or more of the following components in an integral unit. In an alternative form, one or more of the following components may be located as respective te units. .4.1.1 Air filter(s) An RPT device in accordance 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 beginning of the tic path upstream of a pressure generator 4140.

In one form, an outlet air filter 4114, for example an antibacterial filter, is located between an outlet of the tic block 4020 and a patient interface 3000.

James & Wells Ref: 506137NZ .4.1.2 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 r 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 d in the pneumatic path n the pressure generator 4140 and a t 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 llable blower 4142.

For example the blower 4142 may e a brushless DC motor 4144 with one or more impellers housed in a volute. The blower may be capable of delivering a supply of air, for example 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 ing patents or patent applications the contents of which are incorporated 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 ation No.

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

In other forms, a pressure generator 4140 may be a piston-driven pump, a pressure regulator connected to a high pressure source (e.g. compressed air reservoir), or a bellows. .4.1.4 Transducer(s) Transducers may be internal of the RPT device, or external of the RPT device. External transducers may be located for example on or form part of the air t, e.g., the patient interface. External transducers may be in the form of non- James & Wells Ref: 506137NZ contact sensors such as a Doppler radar movement sensor that it or transfer data to the RPT device.

In one form of the present technology, one or more transducers 4270 are located upstream and/or downstream of the re generator 4140. The one or more transducers 4270 may be constructed and arranged to generate s representing properties of the flow of air such as a flow rate, a pressure or a temperature at that point in the pneumatic path.

In one form of the present technology, one or more transducers 4270 may be located ate to the t interface 3000.

In one form, a signal from a ucer 4270 may be filtered, such as by low-pass, high-pass or band-pass filtering. .4.1.4.1 Flow rate sensor A flow rate sensor in accordance with the present technology may be based on a differential pressure transducer, for example, an SDP600 Series differential pressure transducer from SENSIRION.

In one form, a signal representing a flow rate from the flow rate sensor is received by the central controller . .4.1.4.2 Pressure sensor A pressure sensor in accordance with the present logy is located in fluid communication with the pneumatic path. An e of a suitable pressure sensor is a transducer from the HONEYWELL ASDX series. An alternative suitable pressure sensor is a transducer from the NPA Series from GENERAL ELECTRIC.

In one form, a signal from the pressure sensor is received by the central controller . .4.1.4.3 Motor speed transducer In one form of the present technology a motor speed transducer is used to determine a rotational velocity of the motor 4144 and/or the blower 4142. A motor James & Wells Ref: 506137NZ speed signal from the motor speed transducer may be provided to the therapy device controller . The motor speed transducer may, for example, be a speed sensor, such as a Hall effect sensor. .4.1.5 Anti-spill back valve In one form of the present technology, an pill back valve 4160 is located between the humidifier 5000 and the pneumatic block 4020. The anti-spill back valve is constructed 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 electrical components .4.2.1 Power supply A power supply 4210 may be located internal or external of the external housing 4010 of the RPT device 4000.

In one form of the present technology, power supply 4210 es ical power to the RPT device 4000 only. In another form of the present technology, power supply 4210 provides ical power to both RPT device 4000 and humidifier 5000. .4.2.2 Input devices In one form of the present technology, an RPT device 4000 es one or more input devices 4220 in the form of buttons, switches or dials to allow a person to interact with the device. The buttons, switches or dials may be physical devices, or software devices ible via a touch screen. The buttons, es or dials may, in one form, be physically connected to the external housing 4010, or may, in another form, be in wireless communication with a receiver that is in electrical connection to the central controller .

In one form, the input device 4220 may be constructed and arranged to allow a person to select a value and/or a menu option.

James & Wells Ref: NZ .4.2.3 Central controller In one form of the present technology, the central controller is one or a plurality of sors suitable to control an RPT device 4000.

Suitable processors may include an x86 INTEL processor, a processor based on ARM® Cortex®-M processor from ARM Holdings such as an STM32 series microcontroller from ST MICROELECTRONIC. In certain alternative forms of the t technology, a 32-bit RISC CPU, such as an STR9 series microcontroller from ST MICROELECTRONICS or a 16-bit RISC CPU such as a sor from the MSP430 family of microcontrollers, manufactured by TEXAS INSTRUMENTS may also be suitable.

In one form of the present logy, the central controller is a dedicated electronic circuit.

In one form, the central controller is an application-specific integrated circuit. In another form, the central ller comprises discrete electronic components.

The central controller may be configured to receive input signal(s) from one or more transducers 4270, one or more input devices 4220, and the humidifier 5000.

The central controller may be configured to provide output signal(s) to one or more of an output device , a therapy device controller , a data communication ace , and the humidifier 5000.

In some forms of the present logy, the central controller is configured to implement the one or more methodologies described herein, such as the one or more algorithms expressed as computer programs stored in a non-transitory computer readable storage medium, such as memory . In some forms of the present technology, the central controller may be integrated with an RPT device 4000.

However, in some forms of the present technology, some ologies may be performed by a remotely located device. For example, the ly located device James & Wells Ref: 506137NZ may determine control settings for a ventilator or detect respiratory related events by is of stored data such as from any of the sensors described herein. .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 t may be referred to as an air delivery 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 t 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 heating element may be in a form of a heated wire t, and may comprise one or more ucers, such as temperature s. In one form, the heated wire circuit may be helically wound around the axis of the air circuit 4170.

The heating element may be in communication 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 pneumatic path, such as upstream of the pneumatic block 4020, to the air circuit 4170 and/or to the patient interface 3000. .6 HUMIDIFIER .6.1 Humidifier overview In one form of the t technology there is provided a humidifier 5000 (e.g. as shown in Fig. 5A) to change the te humidity of air or gas for delivery to a patient relative to ambient air. Typically, the humidifier 5000 is used to increase the James & Wells Ref: 506137NZ absolute humidity and increase the temperature of the flow of air ive to t air) before delivery to the patient’s airways.

The humidifier 5000 may comprise a humidifier oir 5110, a humidifier inlet 5002 to receive a flow of air, and a fier outlet 5004 to deliver a humidified 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. .6.2 Humidifier components .6.2.1 Water reservoir According to one arrangement, the humidifier 5000 may comprise a water reservoir 5110 configured to hold, or retain, a volume of liquid (e.g. water) to be evaporated for humidification of the flow of air. The water reservoir 5110 may be configured to hold a predetermined maximum volume of water in order to provide adequate humidification for at least the duration of a respiratory therapy session, such as one evening of sleep. Typically, the reservoir 5110 is configured to hold several hundred itres of water, e.g. 300 millilitres (ml), 325 ml, 350 ml or 400 ml. In other forms, the fier 5000 may be configured to receive a supply of water from an external water source such as a building’s water supply .

According to one aspect, the water reservoir 5110 is configured to add ty to a flow of air from the RPT device 4000 as the flow of air travels therethrough. In one form, the water reservoir 5110 may be configured to encourage the flow of air to travel in a tortuous path through the reservoir 5110 while in contact with the volume of water therein.

According to one form, the reservoir 5110 may be removable from the fier 5000, for example in a lateral direction as shown in Fig. 5A and Fig. 5B.

James & Wells Ref: 506137NZ The reservoir 5110 may also be configured to discourage egress of liquid rom, such as when the reservoir 5110 is displaced and/or rotated from its normal, working orientation, such as through any apertures and/or in between its ponents.

As the flow of air to be humidified by the humidifier 5000 is typically pressurised, the reservoir 5110 may also be configured to prevent losses in pneumatic pressure h leak and/or flow impedance. .6.2.2 tive portion According to one arrangement, the reservoir 5110 comprises a conductive n 5120 configured to allow efficient transfer of heat from the heating 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 le.

All or a part of the conductive portion 5120 may be made of a thermally conductive 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 conductive materials of suitable geometry. .6.2.3 fier reservoir dock In one form, the humidifier 5000 may comprise a fier reservoir dock 5130 (as shown in Fig. 5B) configured to receive the humidifier reservoir 5110.

In some arrangements, 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. .6.2.4 Water level indicator The humidifier reservoir 5110 may comprise a water level tor 5150 as shown in Fig. 5A-5B. In some forms, the water level indicator 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 ed 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 volumes such as 200 ml, 300 ml or 400ml.

James & Wells Ref: 506137NZ .6.2.5 Heating element A heating element 5240 may be provided to the humidifier 5000 in some cases to e a heat input to one or more of the volume of water in the fier reservoir 5110 and/or to the flow of air. The heating element 5240 may comprise a heat generating component such as an electrically resistive heating track. One suitable example of a heating element 5240 is a layered heating element such as one described in the PCT Patent Application Publication No. incorporated herewith by nce in its entirety.

In some forms, the heating element 5240 may be provided in the humidifier base 5006 where heat may be provided to the humidifier reservoir 5110 primarily by conduction as shown in Fig. 5B. .7 BREATHING WAVEFORMS Fig. 6 shows a model typical breath waveform of a person while sleeping.

The horizontal axis is time, and the vertical axis is respiratory flow rate. While the parameter values may vary, a typical breath may have the ing approximate values: tidal , Vt, 0.5L, tion time, Ti, 1.6s, peak inspiratory flow rate, Qpeak, 0.4 L/s, exhalation time, Te, 2.4s, peak expiratory flow rate, Qpeak, -0.5 L/s.

The total duration of the breath, Ttot, is about 4s. The person typically breathes at a rate of about 15 breaths per minute (BPM), with Ventilation, Vent, about 7.5 L/min. A typical duty cycle, the ratio of Ti to Ttot, is about 40%. .8 GLOSSARY For the purposes of the present technology disclosure, in certain forms of the present technology, one or more of the following definitions may apply. In other forms of the present technology, alternative tions may apply. .8.1 General Air: In certain forms of the t technology, air may be taken to mean atmospheric air, and in other forms of the present technology air may be taken to mean some other combination of breathable gases, e.g. atmospheric air enriched with oxygen.

James & Wells Ref: 506137NZ t: 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 surrounding the ent system or patient.

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 ambient humidity may be different to the ty 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., ic) noise may be considered to be the background noise level in the room where a patient is d, other than for example, noise generated by an RPT device or emanating from a mask or patient interface. Ambient noise may be generated by sources outside the room.

Automatic Positive Airway Pressure (APAP) therapy: CPAP therapy in which the ent pressure is automatically adjustable, e.g. from breath to breath, between minimum and maximum limits, depending on the ce or absence of indications of SDB events.

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

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

Flow rate: The volume (or mass) of air delivered 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 quantity, namely a James & Wells Ref: 506137NZ quantity having both magnitude and direction. Flow rate may be given the symbol Q.

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

In the example of patient respiration, a flow rate may be nominally positive for the inspiratory portion of a breathing cycle of a t, 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 d 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 tus constructed and arranged, or configured with a physical structure to be e of providing a therapeutically beneficial amount of water (H2O) vapour to a flow of air to ameliorate a medical respiratory condition of a patient.

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 n a mask and a patient's face. In another example leak may occur in a swivel elbow to the ambient.

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

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

Noise, vent tic): 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.

James & Wells Ref: 506137NZ Patient: A person, whether or not they are suffering from a respiratory condition.

Pressure: Force per unit area. re 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 ascal. In this specification, unless otherwise stated, pressure is given in units of cmH2O.

The pressure in the patient interface is given the symbol Pm, while the treatment pressure, 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 y (RPT): The application of a supply of air to an entrance to the airways at a treatment pressure that is typically positive with respect to atmosphere.

Ventilator: A mechanical device that provides pressure support to a patient to perform some or all of the work of breathing. 1 Materials Silicone or Silicone Elastomer: A tic rubber. In this ication, 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 SILASTIC (included in the range of products sold under this trademark), manufactured by Dow Corning. r manufacturer of LSR is Wacker. Unless otherwise ied 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. (Year? Required?) Polycarbonate: a thermoplastic r of Bisphenol-A Carbonate. .8.1.2 Mechanical properties Resilience: Ability of a al to absorb energy when deformed elastically and to release the energy upon unloading.

James & Wells Ref: 506137NZ Resilient: Will release substantially all of the energy when unloaded.

Includes e.g. certain silicones, and thermoplastic elastomers. ss: The ability of a material per se to resist deformation (e.g. described by a s Modulus, or an indentation hardness 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 e polycarbonate, polypropylene, steel or aluminium, and may not e.g. readily deform under finger pressure.

Stiffness (or rigidity) of a ure 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 torsion. The structure 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.

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

As an example, an I-beam may comprise a different bending stiffness (resistance to a bending load) in a first direction in comparison to a second, orthogonal ion. In another example, a structure or component may be floppy in a first direction and rigid in a second direction. .8.2 Respiratory 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 James & Wells Ref: 506137NZ 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 occurred when an apnea is detected that is due to a reduction in breathing effort, or the absence of breathing effort, despite the airway being patent. A mixed apnea occurs when a reduction or absence of breathing effort coincides with an obstructed airway.

Breathing rate: The rate of spontaneous respiration of a patient, usually measured in breaths per minute.

Duty cycle: The ratio of inhalation time, Ti to total breath time, Ttot.

Effort (breathing): The work done by a spontaneously breathing person attempting to breathe. tory n of a breathing cycle: The period from the start of tory flow to the start of inspiratory flow.

Flow limitation: Flow limitation will be taken to be the state of s in a patient's respiration where an increase in effort by the patient does not give rise to a corresponding increase in flow. Where flow limitation occurs during an inspiratory n of the breathing cycle it may be described as inspiratory flow limitation.

Where flow limitation occurs during an tory portion of the breathing cycle it may be described as expiratory flow limitation.

Types of flow limited atory waveforms: (i) Flattened: Having a rise followed by a relatively flat portion, followed by a fall. (ii) M-shaped: Having two local peaks, one at the leading edge, and one at the trailing edge, and a relatively flat portion between the two peaks. (iii) Chair-shaped: Having a single local peak, the peak being at the leading edge, followed by a relatively flat portion.

James & Wells Ref: 506137NZ (iv) Reverse-chair shaped: Having a relatively flat portion followed by single local peak, the peak being at the trailing edge.

Hypopnea: According to some definitions, a hypopnea is taken to be a reduction in flow, but not a cessation of flow. In one form, a hypopnea may be said to have occurred when there is a reduction in flow below a threshold rate for a duration.

A central hypopnea will be said to have occurred when a hypopnea is detected that is due to a reduction in breathing . In one form in adults, either of the following may be regarded as being hypopneas: (i) a 30% reduction in patient breathing for at least 10 seconds plus an associated 4% desaturation; or (ii) a reduction in patient breathing (but less than 50%) for at least 10 seconds, with an associated ration of at least 3% or an arousal.

Hyperpnea: An increase in flow to a level higher than normal.

Inspiratory portion of a breathing cycle: The period from the start of inspiratory flow to the start of expiratory flow will be taken to be the inspiratory portion of a breathing cycle.

Patency (airway): The degree of the airway being open, or the extent to which the airway is open. A patent airway is open. Airway y may be quantified, for example with a value of one (1) being , and a value of zero (0), being closed (obstructed).

Positive End-Expiratory re (PEEP): The pressure above atmosphere in the lungs that exists at the end of expiration.

Peak flow rate (Qpeak): The maximum value of flow rate during the inspiratory portion of the respiratory flow waveform.

Respiratory flow rate, patient airflow rate, respiratory w rate (Qr): These terms may be understood to refer to the RPT device’s estimate of respiratory flow rate, as opposed to "true respiratory flow rate" or "true respiratory flow rate", James & Wells Ref: 506137NZ which is the actual respiratory flow rate experienced by the patient, usually expressed in litres per minute.

Tidal volume (Vt): The volume of air inhaled or exhaled during normal breathing, when extra effort is not applied. (inhalation) Time (Ti): The on of the inspiratory portion of the atory flow rate rm. (exhalation) Time (Te): The duration of the expiratory portion of the respiratory flow rate waveform. (total) Time (Ttot): The total duration between the start of one inspiratory portion of a respiratory flow rate waveform and the start of the following inspiratory portion of the respiratory flow rate waveform.

Typical recent ventilation: The value of ventilation around which recent values of ventilation Vent over some predetermined timescale tend to cluster, that is, a measure of the central tendency of the recent values of ventilation.

Upper airway obstruction (UAO): includes both partial and total upper airway obstruction. This may be associated with a state of flow limitation, in which the flow rate increases only slightly or may even decrease as the pressure difference across the upper airway increases (Starling resistor behaviour). ation : A measure of a rate of gas being exchanged by the patient’s respiratory system. Measures of ventilation may include one or both of inspiratory and expiratory flow, per unit time. When expressed as a volume per minute, this quantity is often referred to as e ventilation". Minute ation is sometimes given simply as a volume, understood to be the volume per minute. .8.3 Ventilation Adaptive Servo-Ventilator (ASV): A ventilator that has a changeable, rather than fixed target ventilation. The able target ventilation may James & Wells Ref: 506137NZ be learned from some characteristic of the patient, for example, a respiratory characteristic of the patient.

Backup rate: A parameter of a ventilator that establishes the minimum breathing rate (typically in number of s per minute) that the ventilator will deliver to the t, if not triggered by spontaneous respiratory effort.

Cycled: The termination of a ventilator's inspiratory phase. When a ventilator delivers a breath to a spontaneously breathing patient, at the end of the inspiratory portion of the breathing cycle, the ventilator is said to be cycled to stop delivering the breath.

Expiratory positive airway re : a base pressure, to which a pressure varying within the breath is added to produce the desired mask pressure which the ator will attempt to achieve at a given time.

End expiratory pressure (EEP): Desired mask pressure which the ator will attempt to achieve at the end of the expiratory portion of the breath. If the pressure waveform template () is zero-valued at the end of expiration, i.e. () = 0 when  = 1, the EEP is equal to the EPAP.

Inspiratory positive airway pressure (IPAP): Maximum desired mask re which the ventilator will attempt to achieve during the atory portion of the breath.

Pressure support: A number that is indicative of the increase in pressure during ventilator ation over that during ventilator expiration, and generally means the ence in pressure between the maximum value during inspiration and the base pressure (e.g., PS = IPAP – EPAP). In some contexts pressure support means the difference which the ventilator aims to achieve, rather than what it actually achieves.

Servo-ventilator: A ventilator that measures patient ventilation, has a target ventilation, and which adjusts the level of re support to bring the patient ventilation towards the target ventilation.

James & Wells Ref: 506137NZ Spontaneous/Timed (S/T): A mode of a ventilator or other device that attempts to detect the initiation of a breath of a neously breathing patient. If however, the device is unable to detect a breath within a predetermined period of time, the device will automatically initiate delivery of the breath.

Swing: Equivalent term to pressure support.

Triggered: When a ventilator delivers a breath of air to a neously breathing patient, it is said to be triggered to do so at the initiation of the respiratory portion of the breathing cycle by the patient's efforts.

Typical recent ventilation: The typical recent ation Vtyp is the value around which recent measures of ventilation over some predetermined timescale tend to cluster. For example, a e of the central tendency of the measures of ventilation over recent history may be a suitable value of a typical recent ventilation. .8.4 Anatomy .8.4.1 Anatomy of the face Ala: the external outer wall or "wing" of each nostril l: alar) Alar angle: 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 external 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. (nose) Cartilaginous framework: The cartilaginous framework of the nose comprises the septal, lateral, major and minor cartilages.

James & Wells Ref: 506137NZ Columella: the strip of skin that separates the nares and which runs from the pronasale to the upper lip. lla angle: The angle between the line drawn through the midpoint of the nostril aperture and a line drawn perpendicular 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 forehead.

Lateral nasal cartilage: A generally triangular plate of age. Its superior margin is attached to the nasal bone and frontal process of the maxilla, and its inferior margin is ted to the greater alar age.

Lip, lower (labrale inferius): Lip, upper (labrale superius): Greater alar cartilage: A plate of cartilage 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 maxilla by a tough fibrous membrane containing three or four minor cartilages of the ala.

Nares ils): Approximately oidal 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.

James & Wells Ref: 506137NZ Naso-labial angle: The angle between the lla and the upper lip, while intersecting subnasale. ion inferior: The lowest point of attachment 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.

Pronasale: the most protruded point or tip of the nose, which can be identified in lateral view of the rest of the n 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: Located 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.

Midsagittal plane: A vertical plane that passes from anterior (front) to posterior (rear) dividing the body into right and left .

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

Septal cartilage (nasal): The nasal septal cartilage 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.

James & Wells Ref: 506137NZ Supramenton: The point of greatest concavity in the midline of the lower lip between labrale inferius and soft tissue pogonion .8.4.2 Anatomy of the skull Frontal bone: The l bone includes a large vertical portion, the squama frontalis, corresponding to the region known as the forehead.

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 . The frontal process of the a 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 cranial 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 parietal bones are the bones that, when joined together, form the roof and sides of the cranium.

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

Zygomatic bones: The face es two zygomatic bones, located in the upper and lateral parts of the face and forming the prominence of the cheek.

James & Wells Ref: 506137NZ 3 Anatomy of the respiratory system agm: A sheet of muscle that extends across the bottom of the rib cage. The diaphragm separates the ic cavity, containing the heart, lungs and ribs, from the abdominal cavity. As the agm contracts the volume of the ic 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 trachea.

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

The atory 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 conchae (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 cavity, 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). .8.5 Patient 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 excessive CO2 rebreathing by a patient.

Elbow: An elbow is an example of a structure that directs an axis of flow of air ling therethrough to change direction through an angle. In one form, the James & Wells Ref: 506137NZ 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 cross-section. In certain forms an elbow may be rotatable with respect to a mating component, e.g. about 360 degrees. In certain forms an elbow may be removable from a mating component, e.g. via a snap connection. In certain forms, an elbow may be led to a mating component via a one-time snap during cture, 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 ure in the mask. However, some forms of mask frame may also be air-tight.

Functional dead space: (description to be inserted here) Headgear: Headgear will be taken to mean a form of positioning and izing structure designed for use on a head. For example the ar may comprise a collection of one or more struts, ties and stiffeners configured to locate and retain a patient interface in on on a patient’s face for delivery of respiratory therapy. Some ties are formed of a soft, flexible, elastic material such as a laminated composite of foam and fabric.

Membrane: Membrane will be taken to mean a typically thin element that has, preferably, substantially no resistance to bending, but has resistance to being stretched.

Plenum chamber: a mask plenum chamber will be taken to mean a portion of a t 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 ed to ‘seal’ or to effect ‘sealing’ therebetween t requiring a separate ‘seal’ element per se.

James & Wells Ref: 506137NZ Shell: A shell will be taken to mean a curved, vely thin structure having g, tensile and compressive stiffness. For example, 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. ner: A stiffener will be taken to mean a structural component designed to increase the bending resistance 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 direction.

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 s. In another form, the swivel may be ucted to rotate through an angle less than 360 degrees. When used in the t of an air delivery t, the sub-assembly of components preferably comprises a matched 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 ure that allows a flow of air from an interior of the mask, or conduit, to ambient air for clinically effective washout of exhaled gases. For example, a clinically effective washout may e a flow rate of about 10 litres per minute to about 100 litres per minute, depending on the mask design and treatment pressure. .8.6 Shape of structures Products in accordance with the present technology may comprise one or more three-dimensional mechanical structures, for example a mask cushion or an impeller. The three-dimensional structures may be bounded by two-dimensional surfaces. These surfaces may be distinguished using a label to describe an associated surface orientation, location, function, or some other characteristic. For example a James & Wells Ref: 506137NZ 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 e, a ure may comprise a first e and a second surface.

To facilitate describing the shape of the three-dimensional structures and the surfaces, we first consider a section through a surface of the structure at a point, p. See Fig. 3B to Fig. 3F, which illustrate es 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. .8.6.1 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 curvature 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 ed to Fig. 3C) and Fig. 3C ively small positive curvature compared to Fig. 3B). Such curves are often referred to as concave.

Zero ure: If the curve at p is a straight line, the curvature 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 ure compared to Fig. 3F) and Fig. 3F (relatively large negative ure compared to Fig. 3E). Such curves are often referred to as convex.

James & Wells Ref: 506137NZ .8.6.2 Curvature of two dimensional surfaces A description of the shape at a given point on a two-dimensional surface in accordance with the present technology may include multiple normal crosssections.

The multiple cross-sections may cut the surface in a plane that includes the outward normal (a l plane"), and each cross-section may be taken in a different direction. Each cross-section results in a plane curve with a corresponding curvature.

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

Each of the curvatures at that point has a magnitude, e.g. relatively 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 ure of the curve takes its maximum and minimum values are called the pal directions. In the examples of Fig. 3B to Fig. 3F, the m curvature occurs in Fig. 3B, and the m occurs in Fig. 3F, hence Fig. 3B and Fig. 3F are cross sections in the principal 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 ures have the same sign, e.g. both positive (a ve dome") or both negative (a "convex 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.

James & Wells Ref: 506137NZ Planar region: A region of a surface where both of the principal ures are zero (or, for example, zero within manufacturing tolerances).

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

Path: In certain forms of the present technology, ‘path’ will be taken to mean a path in the mathematical – topological sense, e.g. a uous space curve from f(0) to f(1) on a surface. In n 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 for the imaginary person is where they walk on the e, 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 e. There may be more than one path between two points on a surface and such paths may have different 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 n 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 person, the straight-line ce would correspond to the distance ‘as the crow flies’.) .8.6.3 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 nts. 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 typical 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 James & Wells Ref: 506137NZ 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 l, a space curve may be described by a curvature and a torsion at each point on the space curve. n is a measure of how the curve turns out of a plane. Torsion has a sign and a magnitude.

The torsion at a point on a space curve may be characterised with reference to the tangent, 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 direction 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 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 direction that the tangent vector is changing is called the unit principal normal . It is perpendicular to the tangent vector.

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

Osculating plane: The plane ning the unit tangent vector and the unit principal normal vector. See Figures 3O and 3P.

Torsion of a space curve: The torsion at a point of a space curve is the ude of the rate of change of the binormal unit vector at that point. It measures how much the curve deviates from the ting plane. A space curve which lies in a plane has zero torsion. 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 l 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 helical path). With reference to Fig. 3S, since T2>T1, the magnitude of the James & Wells Ref: 506137NZ torsion near the top coils of the helix of Fig. 3S is greater than the magnitude of the n of the bottom coils of the helix of Fig. 3S With nce to the right-hand rule of Fig. 3P, a space curve turning towards the direction of the right-hand binormal may be considered as having a righthand positive torsion (e.g. a hand helix as shown in Fig. 3S). A space curve turning away from the direction 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 ion of the left-hand binormal may be considered as having a and positive torsion (e.g. a left-hand helix). Hence left-hand positive is equivalent to right-hand ve. See Fig. 3T. .8.6.4 Holes A surface may have a mensional 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 ure shown in Fig. 3I, bounded 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 interior surface bounding a two dimensional hole indicated. In a yet another example, a t may comprise a one-dimension hole (e.g. at its entrance or at its exit), and a two-dimension hole bounded by the inside surface of the conduit. See also the two ional hole through the structure shown in Fig. 3K, bounded by a surface as shown. .9 OTHER REMARKS A portion of the disclosure of this patent nt 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 James & Wells Ref: 506137NZ appears in Patent Office patent files or records, but otherwise reserves all copyright rights whatsoever.

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 logy. 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 ed limit in the stated range. Where the stated range includes one or both of the , 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 approximated, unless ise stated, and such values may be utilized to any suitable significant digit to the extent that a practical technical implementation may permit or require it.

Unless defined ise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology s. gh any methods and materials r or equivalent to those described herein can also be used in the practice or testing of the present technology, a limited number of the exemplary methods and als 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 contrary, any and all components herein described are understood to be capable of being manufactured and, as such, may be manufactured together or separately.

James & Wells Ref: 506137NZ It must be noted that as used herein and in the appended claims, the singular forms "a", "an", and "the" include their plural equivalents, unless the context clearly dictates otherwise.

All publications mentioned herein are incorporated herein by reference in their entirety to disclose and describe the s and/or materials which are the subject of those publications. The publications discussed herein are ed 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 ed to antedate such ation 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, ting 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 tions.

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 elements. Furthermore, gh process steps in the methodologies may be described or rated in an order, such an ordering is not required. Those skilled in the art will recognize that such ordering may be modified and/or aspects thereof may be conducted concurrently or even synchronously.

James & Wells Ref: 506137NZ It is therefore to be tood 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. .10 REFERENCE SIGNS LIST t 1000 bed partner 1100 patient interface 3000 seal - forming structure 3100 connection region 3102 anterior opening 3104 posterior opening 3106 anterior tie 3108 support structure 3110 interior surface 3112 patient contacting surface 3114 tient contacting surface 3116 edge 3118 gas chamber 3120 undercushion 3122 plenum chamber 3200 chord 3210 James & Wells Ref: 506137NZ superior point 3220 inferior point 3230 oning and stabilising structure 3300 conduit 3301 strap connector 3302 clip 3303 flexible portion 3304 elbow connector 3305 vent 3400 opening 3401 opening 3402 decoupling structure 3500 swivel 3501 patient interface connector 3502 tube 3503 connection port 3600 forehead support 3700 RPT device 4000 al housing 4010 upper portion 4012 James & Wells Ref: NZ portion 4014 panel 4015 chassis 4016 handle 4018 pneumatic block 4020 air filter 4110 inlet air filter 4112 outlet air filter 4114 muffler 4120 inlet muffler 4122 outlet muffler 4124 pressure generator 4140 blower 4142 motor 4144 anti - spill back valve 4160 air circuit 4170 supplemental oxygen 4180 electrical components 4200 PCBA 4202 power supply 4210 James & Wells Ref: 506137NZ input device 4220 transducer 4270 fier 5000 humidifier inlet 5002 humidifier outlet 5004 humidifier base 5006 reservoir 5110 conductive portion 5120 humidifier reservoir dock 5130 locking lever 5135 water level indicator 5150 heating element 5240 James & Wells Ref: 506137NZ

Claims (19)

1. A seal-forming structure for a patient interface, the seal-forming structure constructed and arranged to form a seal with a region of the patient’s face nding an entrance to the patient’s airways, the seal-forming structure constructed and arranged to maintain a therapeutic re of at least 6 cmH2O above ambient air pressure in a plenum chamber throughout the patient’s respiratory cycle in use, the orming structure comprising: a patient-contacting surface configured to engage the patient’s facial skin to form a seal; a posterior opening formed in the patient-contacting surface, the posterior opening ured to provide the flow of air at said therapeutic pressure to the patient’s nares; and a support structure extending from a first location on the patient contacting surface to a second location on an interior surface of the seal-forming structure, the support structure and the interior surface g a uous loop, 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 interface is configured to leave the patient’s mouth uncovered, and n a superior and medialmost portion of the seal-forming structure is structured to engage the patient’s nose inferior to the patient’s nasal bone.

2. The seal-forming structure of claim 1, further comprising an anterior g formed in a tient contacting surface and an anterior tie that spans the anterior opening, and wherein a first end of the support structure is connected to the anterior tie. James & Wells Ref: 506137NZ

3. The seal-forming ure of claim 2, further comprising an edge bounding the posterior opening in the patient contacting surface, and wherein a second end of the support structure is connected to the patient contacting surface at a or region of the edge.

4. The orming structure of any one of claims 1 to 3, wherein the support ure has a length in an rmed state that is greater than a linear distance from the first location to the second location.

5. The seal-forming structure of any one of claims 1 to 4, wherein the support structure is ured to be positioned adjacent to or in contact with the patient’s columella during use.

6. The seal-forming structure of any one of claims 1 to 5, wherein the support structure is curved along a longitudinal axis of the support structure in an undeformed state.

7. The seal-forming structure of any one of claims 1 to 6, wherein the support structure has a different thickness than the patient-contacting surface.

8. The seal-forming structure of any one of claims 1 to 7, wherein the support structure is thicker than the patient-contacting surface.

9. The seal-forming structure of any one of claims 1 to 8, wherein the support ure does not extend completely across the ior opening.

10. The seal-forming structure of any one of claims 1 to 9, wherein the sealforming structure at least partly forms a gas r, and wherein in an undeformed state the support structure extends into the gas chamber.

11. The seal-forming structure of any one of claims 1 to 10, wherein the support structure has a variable thickness in a longitudinal direction. James & Wells Ref: 506137NZ

12. The seal-forming structure of any one of claims 1 to 11, n the support structure has an increased thickness adjacent the first on and/or the second location.

13. The seal-forming structure of any one of claims 1 to 11, wherein a portion of the support structure is curved away from the t’s nose along a longitudinal axis of the support structure in an undeformed state.

14. The seal-forming structure of any one of claims 1 to 13, r comprising an undercushion that supports the patient contacting surface.

15. The seal-forming structure of claim 14, n an inferior portion of the seal-forming structure includes the undercushion and a or portion of the sealforming structure does not include the undercushion.

16. The orming structure of claim 15, wherein the undercushion is ured to only support the patient contacting surface against the patient’s lip

17. The seal-forming structure of any one of claims 1 to 16, wherein the superior and medialmost portion of the seal-forming structure is structured to engage the patient’s nose inferior to the patient’s pronasale.

18. The seal-forming structure of any one of claims 1 to 17, wherein an inferior portion of the seal-forming structure is structured to engage the patient’s lip superior such that the seal-forming structure does not extend beyond the lip superior to the patient’s upper vermilion.

19. A patient interface comprising: a plenum chamber 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 re for breathing by a patient, a seal-forming structure as claimed in any one of the claims 1 to 18; James & Wells Ref: 506137NZ a positioning and ising structure to provide a force to hold the seal-forming structure in a therapeutically effective position on the patient’s head, the positioning and stabilising structure sing a tie, the tie being constructed and arranged so that at least a portion overlies a region of the patient’s head superior to an ion superior of the patient’s head in use; and a vent ure to allow a continuous 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 interface is configured to leave the patient’s mouth uncovered. James & Wells Ref: NZ 4000 5000 4170 3000 1000 1100 James & Wells Ref: NZ 1000 3000 4170 5000 4000 James & Wells Ref: NZ 4000 5000 4170 James & Wells Ref: 506137NZ Nasal cavity Oral cavity Larynx Vocal folds Alveolar sacs Oesophagus Trachea Bronchus Heart Diaphragm ght 2012 ResMed Limited James & Wells Ref: 506137NZ Nasal cavity Nasal bone Lateral nasal Greater alar cartilage Hard palate Nostril Soft palate Lip superior Lip inferior Oropharynx Tongue Epiglottis Vocal folds Larynx Esophagus Trachea Copyright 2012 ResMed Limited James & Wells Ref: 506137NZ Sagittal plane Superior Inferior Right Left Endocanthion Nasal ala Lip Superior Nasolabial sulcus Upper Vermillion Lower Vermillion Cheilion Lip or Mouth width radially inward radially outward Copyright 2012 ResMed Limited James & Wells Ref: 506137NZ Otobasion superior Otobasion inferior Alar crest point Glabella Pronasale Subnasale Sellion Posterior Ridge Lip or Lip Inferior Supramenton Superior Inferior Anterior Copyright 2012 ResMed Limited James & Wells Ref: 506137NZ Coronal plane Frankfort ntal Nasolabial angle Posterior Superior Inferior Anterior Copyright 2012 ResMed Limited James & Wells Ref: 506137NZ Sagittal plane Pronasale columella Subnasale Naris Major axis FIG . 2F of naris Upper vermilion Lip inferior abial sulcus Copyright 2012 ResMed Limited James & Wells Ref: 506137NZ