CN115334982A

CN115334982A - Endoscope clearing system and method

Info

Publication number: CN115334982A
Application number: CN202180017112.6A
Authority: CN
Inventors: 库尔特·G·谢尔顿; 米切拉·C·弗里格特
Original assignee: Gyrus ACMI Inc
Current assignee: Gyrus ACMI Inc
Priority date: 2018-02-09
Filing date: 2021-02-25
Publication date: 2022-11-11
Also published as: JP2023515207A; EP3749167A1; US20200187761A1; CN111683580A; EP3749167A4; BR112020016161A2; DE112021001260T5; JP2021512721A; US20200405130A9; AU2019217992B2; AU2019217992A1; MX2020008318A; WO2019157406A1; US20200187768A1; US20210045812A1; US20210045811A1; WO2021173775A1; BR112020016159A2; AU2019216954B2; JP7498287B2

Abstract

Systems and methods for clearing a working channel in a medical device in situ during a procedure are disclosed. An exemplary deoccluding system comprises: a flow sensor sensing a flow rate through the working channel; and a control module that detects a channel condition indicative of a presence or absence of a blockage based on the flow rate. In the event of a channel blockage, the control module may control one or more of the irrigation or aspiration sources to provide irrigation fluid or aspiration pressure, respectively, to unblock the blocked channel. The control module may adjust one or more of an irrigation flow rate or an aspiration flow rate through the working channel during the procedure to maintain a desired pressure of the anatomical environment at the anatomical site or to maintain a desired flow condition in the working channel.

Description

Endoscope clearing system and method

Priority claim

This application claims priority to U.S. patent application serial No. 16/803,612, filed on 27/2/2020, the contents of which are incorporated herein by reference in their entirety.

Technical Field

The present disclosure relates generally to endoscopic systems, and more particularly to a deoccluding system for deoccluding an endoscope during an endoscopic procedure while maintaining in situ pressure of an anatomical environment at an anatomical site under control.

Background

Endoscopes are commonly used to provide access to internal locations of patients, thereby providing a visual access channel for physicians. Some endoscopes are used in minimally invasive surgery to remove unwanted tissue or foreign bodies from a patient. For example, endoscopic tissue removal devices are the following instruments: used by clinicians to remotely access necrotic, cancerous, damaged, infected, or otherwise unwanted soft tissue, bone, or other anatomical structures at an anatomical site, resect the unwanted material from adjacent anatomical structures, and transport them away from the anatomical site. Clinicians use nephroscopes to examine the renal system and perform various procedures under direct visual control. For example, percutaneous nephrolithotomy (PCNL) is a procedure that involves placing a nephroscope into the renal pelvis through the patient's flank. Stones or bumps from various regions of the body including, for example, the urinary system, gall bladder, nasal passages, gastrointestinal tract, stomach, or tonsils may be visualized and extracted. Larger sized stones may be ablated into smaller fragments using an oscillating force such as a shock wave, ultrasonic energy (via a dedicated device such as an ultrasonic lithotripter), or a laser.

Some endoscopes have a suction channel (also referred to as a suction channel) to deliver resected tissue, stones (e.g., stones or stone fragments in various stone-forming regions), and masses and other unwanted material. A flow of irrigant (e.g., saline solution) may be introduced to the anatomical site through an irrigation channel in the endoscope during surgery. The irrigation fluid may facilitate removal of tissue fragments, stone fragments, and other unwanted matter through the aspiration channel. The irrigation fluid may also help the clinician performing the procedure maintain clear visibility of the anatomical environment. In addition, the irrigation flow has a cooling effect on the endoscopic tissue removal device and may help dissipate heat generated during ablation of stones (e.g., kidney stones).

Unwanted material generated during endoscopic procedures may accumulate and clog the working channel (e.g., aspiration channel or irrigation channel) of the scope. Monitoring whether the channel is blocked and effectively dredging the blocked channel in time can shorten the operation time and improve the efficiency, safety and success rate of the endoscopic operation.

Disclosure of Invention

Systems and methods are described herein for in situ clearing of a working channel of an endoscope during endoscopic surgery while maintaining pressure at the anatomical site under control during endoscopic surgery. According to an aspect herein, a deoccluding system comprises: a flow sensor configured to sense a flow rate through a working channel of an endoscope; and a control module configured to detect a channel condition indicative of the presence or absence of a blockage in the working channel using the sensed flow rate. In response to the presence of an occlusion in the working channel, the control module may control one or more of the irrigation source or the aspiration source to provide irrigation fluid or aspiration pressure, respectively, to the working channel to unblock the working channel. The control module may automatically adjust one or more of an irrigation flow rate or an aspiration flow rate through the working channel during the endoscopic procedure to maintain a pressure of the anatomical environment at the anatomical site at a substantially desired pressure level (e.g., a predetermined or user-specified pressure level), or to achieve a desired flow condition corresponding to the desired pressure. Irrigation fluid or suction pressure may be applied as long as the channel blockage remains present.

Example 1 is a system for clearing at least one working channel of a medical device during a procedure on a patient. The system comprises: a flow sensor configured to sense a flow rate through at least one working channel of a medical device; and a control module configured to: detecting a channel condition using the sensed flow rate, the channel condition indicating the presence or absence of a blockage in the at least one working channel; and in response to the detected channel condition indicating the presence of an occlusion in the at least one working channel, controlling one or more of the irrigation source or the aspiration source to provide irrigation fluid or aspiration pressure, respectively, to unblock the at least one working channel.

In example 2, the subject matter of example 1 optionally includes a control module that can be configured to: one or more of the irrigation or aspiration sources are controlled to provide irrigation fluid or aspiration pressure, respectively, to unblock the at least one working channel whenever the detected channel condition indicates the presence of an occlusion in the at least one working channel.

In example 3, the subject matter of any of examples 1-2 optionally includes a control module that may be configured to: detecting a blockage in the at least one working channel in response to the sensed flow rate decreasing below a first threshold; and detecting an absence of a blockage in the at least one working channel in response to the sensed flow rate increasing above a second threshold.

In example 4, the subject matter of any one or more of examples 1-3 optionally includes a control module that can be configured to: unblocking the at least one working channel includes alternating between applying irrigation fluid and applying suction pressure to the at least one working channel.

In example 5, the subject matter of any one or more of examples 1-4 optionally includes a control module that can be configured to: controlling one or more of the irrigation source or the suction source to unblock the at least one working channel by adjusting a flow rate of the irrigation fluid or a flow rate of the suction pressure, respectively.

In example 6, the subject matter of any one or more of examples 3 to 5 optionally includes: a user input configured to receive a desired pressure from a user to be applied to an anatomical environment at an anatomical site of a patient; and a pressure sensor configured to sense a pressure of an anatomical environment at the anatomical site; and wherein the control module is configured to adjust one or more of an irrigation flow rate or an aspiration flow rate through the at least one working channel to maintain the sensed pressure at a substantially desired pressure level.

In example 7, the subject matter of example 6 can optionally include: a user input configured to receive a desired flow condition in at least one working channel, the desired flow condition corresponding to a desired pressure to be applied to an anatomical environment; and a control module configured to control one or more of an irrigation flow rate or an aspiration flow rate through at least one working channel of the medical device to maintain a desired flow condition.

In example 8, the subject matter of any one or more of examples 6 to 7 optionally includes: at least one working channel, which may include a suction channel and an irrigation channel; and a control module that may be configured to: fluidly coupling an irrigation source to one of the irrigation channel or the aspiration channel to provide irrigation fluid thereto at an adjustable irrigation flow rate; and fluidly coupling a suction source to the other of the irrigation channel or the suction channel to provide a suction pressure thereto at an adjustable suction flow rate.

In example 9, the subject matter of example 8 optionally includes a control module that can be configured to: controlling an irrigation source to provide irrigation to the aspiration channel in response to the presence of an occlusion in the aspiration channel; in response to a sensed increase in pressure of the anatomical environment at the anatomical site, controlling the suction source to apply suction pressure to the irrigation channel to maintain the sensed pressure at a substantially desired pressure level; and in response to the absence of an occlusion in the aspiration channel, controlling the aspiration source to apply aspiration pressure to the aspiration channel and controlling the irrigation source to provide irrigation fluid to the irrigation channel.

In example 10, the subject matter of example 8 optionally includes a control module that can be configured to: in response to the presence of an occlusion in the irrigation channel, controlling the suction source to apply suction pressure to the irrigation channel; in response to a sensed decrease in pressure of the anatomical environment at the anatomical site, controlling the irrigation source to provide irrigation fluid to the aspiration channel to maintain the sensed pressure at a substantially desired pressure level; and in response to the absence of an occlusion in the irrigation channel, controlling the suction source to apply suction pressure to the suction channel and controlling the irrigation source to provide irrigation fluid to the irrigation channel.

In example 11, the subject matter of example 9 can optionally include the desired pressure, which can be a substantially net zero pressure, and wherein the control module can be configured to: in response to the sensed increase in pressure, the suction source is controlled to apply suction pressure to the irrigation channel at a level that substantially neutralizes the sensed increase in pressure.

In example 12, the subject matter of example 10 can optionally include the desired pressure, which can be a substantially net zero pressure, and wherein the control module can be configured to: in response to the sensed decrease in pressure, the irrigation source is controlled to provide irrigation fluid to the aspiration channel at an irrigation flow rate that substantially neutralizes the sensed decrease in pressure.

In example 13, the subject matter of example 9 can optionally include the desired pressure, which can be a positive pressure, and wherein the control module can be configured to: in response to the sensed increase in pressure, the suction source is controlled to apply suction pressure to the irrigation channel at a level to maintain the sensed pressure at a substantially desired level of positive pressure.

In example 14, the subject matter of example 10 can optionally include the desired pressure, which can be a positive pressure, and wherein the control module can be configured to: in response to a decrease in the sensed pressure, the irrigation source is controlled to provide irrigation fluid to the aspiration channel at an irrigation flow rate such that the sensed pressure is maintained at a level of substantially the desired positive pressure.

In example 15, the subject matter of example 9 can optionally include the desired pressure, which can be a negative pressure, and wherein the control module can be configured to: in response to the increase in the sensed pressure, the suction source is controlled to apply suction pressure to the irrigation channel at a level to maintain the sensed pressure at substantially the desired level of negative pressure.

In example 16, the subject matter of example 10 can optionally include the desired pressure, which can be a negative pressure, and wherein the control module can be configured to: in response to a decrease in the sensed pressure, the irrigation source is controlled to provide irrigation fluid to the aspiration channel at an irrigation flow rate such that the sensed pressure is maintained at substantially the desired negative pressure level.

Example 17 is an endoscopic surgical system, comprising: an endoscope comprising an imaging module, a surgical module, and at least one working channel configured to conduct irrigation fluid or suction pressure; a user input configured to receive a desired pressure from a user to be applied to an anatomical environment at an anatomical site of a patient; a flow sensor configured to sense a flow rate through at least one working channel of the endoscope; a pressure sensor configured to sense a pressure of an anatomical environment at an anatomical site; and a control module configured to: detecting a channel condition using the sensed flow rate, the channel condition indicating the presence or absence of a blockage in the at least one working channel; controlling one or more of the irrigation source or the aspiration source to provide irrigation fluid or aspiration pressure, respectively, to unblock the at least one working channel in response to the detected channel condition indicating the presence of the occlusion in the at least one working channel and so long as the detected channel condition indicates the presence of the occlusion in the at least one working channel; and adjusting one or more of an irrigation flow rate or an aspiration flow rate through the at least one working channel to maintain the sensed pressure at a substantially desired pressure level.

Example 18 is a method of clearing at least one working channel of a medical device during a procedure of a patient. The method comprises the following steps: sensing a flow rate through at least one working channel of a medical device via a flow sensor; detecting, via the control module, a channel condition using the sensed flow rate, the channel condition indicating a presence or absence of a blockage in the at least one working channel; and in response to the detected channel condition indicating the presence of an occlusion in the at least one working channel, controlling one or more of the irrigation source or the aspiration source to provide irrigation fluid or aspiration pressure, respectively, to unblock the at least one working channel.

In example 19, the subject matter of example 18 optionally includes: the irrigation fluid or suction pressure may continue to be provided to unblock the at least one working channel as long as the detected channel condition indicates the presence of an occlusion in the at least one working channel.

In example 20, the subject matter of any one or more of examples 18 to 19 optionally includes detecting a channel state, which may include: detecting a blockage in the at least one working channel in response to the sensed flow rate decreasing below a first threshold; and detecting an absence of a blockage in the at least one working channel in response to the sensed flow rate increasing above a second threshold.

In example 21, the subject matter of any one or more of examples 18 to 20 optionally includes unclogging the at least one working channel, which can include alternating between applying irrigation fluid and applying suction pressure to the at least one working channel.

In example 22, the subject matter of any one or more of examples 18 to 21 optionally includes: receiving, via a user input, a desired pressure to be applied to an anatomical environment at an anatomical site of a patient; sensing, via a pressure sensor, a pressure of an anatomical environment at an anatomical site; and adjusting one or more of an irrigation flow rate or an aspiration flow rate through the at least one working channel to maintain the sensed pressure at a substantially desired pressure level.

In example 23, the subject matter of example 22 can optionally include the steps of: receiving a desired flow condition in at least one working channel, the desired flow condition corresponding to a desired pressure to be applied to an anatomical environment; and adjusting one or more of an irrigation flow rate or an aspiration flow rate through the at least one working channel to maintain a desired flow condition.

In example 24, the subject matter of example 22 can optionally include at least one working channel, which can include a suction channel and an irrigation channel. The method comprises the following steps: controlling an irrigation source to provide irrigation fluid to the aspiration channel in response to the presence of an occlusion in the aspiration channel; in response to a sensed increase in pressure of the anatomical environment at the anatomical site, controlling a suction source to apply suction pressure to the irrigation channel to maintain the sensed pressure at a substantially desired pressure level; and in response to the absence of an occlusion in the aspiration channel, controlling the aspiration source to apply aspiration pressure to the aspiration channel and controlling the irrigation source to provide irrigation fluid to the irrigation channel.

In example 25, the subject matter of example 22 can optionally include at least one working channel, which can include a suction channel and an irrigation channel. The method comprises the following steps: controlling a suction source to apply suction pressure to the irrigation channel in response to the presence of an occlusion in the irrigation channel; in response to a sensed decrease in pressure of the anatomical environment at the anatomical site, controlling the irrigation source to provide irrigation fluid to the aspiration channel to maintain the sensed pressure at a substantially desired pressure level; and in response to the absence of an occlusion in the irrigation channel, controlling the suction source to apply suction pressure to the suction channel and controlling the irrigation source to provide irrigation fluid to the irrigation channel.

This summary is an overview of some of the teachings of the present application and is not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details regarding the present subject matter may be found in the detailed description and appended claims. Other aspects of the disclosure will be apparent to those skilled in the art upon reading and understanding the following detailed description and viewing the drawings that form a part thereof, each of which is not to be taken in a limiting sense. The scope of the present disclosure is defined by the appended claims and their legal equivalents.

Drawings

Various embodiments are shown by way of example in the drawings. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present subject matter.

Fig. 1 is a block diagram illustrating an example of a system for in situ clearing a working channel of an endoscope and maintaining a pressure of an anatomical environment at an anatomical site at a substantially desired level during a minimally invasive procedure.

Fig. 2A-2B are diagrams illustrating a powered tissue removal device 200 that may be used in a system as described with reference to fig. 1.

Fig. 3A-3B are diagrams illustrating an endoscopic system for clearing an obstructed channel and maintaining the pressure of the anatomical environment at a substantially desired level during endoscopic surgery.

Fig. 4A illustrates an exemplary technique for unclogging an obstructed working channel of an endoscope, according to embodiments discussed herein.

Fig. 4B to 4C are graphs showing the flow rate change in the working channel in the presence of clogging and during the dredging process.

FIG. 5 is a diagram illustrating an exemplary feedback control pressure regulation system that regulates ambient pressure in the absence of channel blockage.

Fig. 6A is a diagram illustrating an exemplary feedback control pressure regulation system that regulates ambient pressure in the presence of an occlusion in the aspiration channel.

Fig. 6B is a timing diagram for enabling irrigation/aspiration in the aspiration channel during deocclusion of the occluded aspiration channel.

Fig. 6C is a timing diagram of enabling irrigation/aspiration in the irrigation channel to maintain a desired pressure at the anatomical site during deocclusion of the occluded aspiration channel.

FIG. 7A is a diagram illustrating an exemplary feedback control pressure regulation system that regulates ambient pressure in the presence of a blockage in the flush channel.

Fig. 7B is a timing diagram for enabling irrigation/aspiration in an irrigation channel during deocclusion of an obstructed irrigation channel.

Fig. 7C is a timing diagram for enabling irrigation/suction in the suction channel during clearing of an obstructed irrigation channel to maintain a desired pressure at the anatomical site.

FIG. 8 is a flow chart illustrating a method for in situ clearing of a working channel in a medical device during minimally invasive surgery.

Fig. 9 is a flow chart illustrating a method for clearing a working channel of a medical device in situ and maintaining a pressure of an anatomical environment at an anatomical site at a substantially desired level.

Detailed Description

Endoscopes include tubular sections that can be inserted into the interior of an organ or cavity of the body to aid in diagnosis or treatment. One or more working channels (e.g., aspiration channel and/or irrigation channel) may be disposed inside the tubular portion and extend along the length of the tubular portion. To reduce the risk of damaging unintended tissue, the insertable tubular portion may have a small diameter. Thus, the working channel also has a small lumen diameter. Since tissue fragments and foreign objects (e.g., stones and their debris) typically have dimensions of one to two lumen diameters in length, some tissue or stone particles may accumulate and clog the working channel.

Herein, "clogging" refers to the accumulation of tissue fragments, stones (e.g., kidney stones or stone debris), and other materials and the partial or complete occlusion of the passage lumen, and "clogging" refers to the partially or completely occluded state of the passage lumen. Any working channel of the endoscope may become blocked. Blockages in the aspiration channel may significantly reduce the efficiency of tissue debris and stone debris removal therethrough. Delaying or inefficiently removing unwanted material from the anatomical site may inhibit or prevent further treatment (e.g., debridement or stone ablation), contaminate the anatomical site, and expose the patient to increased risk. On the other hand, blockages in the irrigation channel may reduce the volume and/or flow rate of irrigation fluid flowing therethrough and supplied to the anatomical environment. A slow irrigation flow may be less effective in flushing unwanted material from the anatomical site and increases the likelihood of blockage in the aspiration channel. The reduced irrigation volume and flow rate may also affect its cooling effect on the surgical member and the anatomical environment and increase the chance of heat buildup at the anatomical site. Furthermore, any blockage in the working channel can block the lens of the endoscope, impairing the visibility of the object under examination and reducing the quality of the images taken in the anatomical environment, thereby increasing the difficulty and time of the procedure.

Suction and irrigation may cause negative and positive pressure changes, respectively, of the anatomical environment at the anatomical site. If not properly controlled, negative pressure variations and positive pressure variations may be detrimental to internal organs exposed to the anatomical site. For example, while the body may regulate some positive pressure changes, many organs are relatively immune to negative pressure changes. An occlusion in a working channel (e.g., a suction channel or an irrigation channel) may disrupt the pressure balance between the positive pressure associated with fluid flow and the negative pressure associated with suction, thereby exposing internal organs at the anatomical site to harmful excessive positive or negative pressures.

Various approaches have been attempted to prevent or address channel blockage in endoscopes. For example, breaking up unwanted material (e.g., tissue fragments or stone debris) into finer pieces can reduce the likelihood of clogging in the channel. However, this may consume more energy, take longer procedure time, and potentially increase patient risk due to increased procedure complexity and time. Fine particles or stone powder may reduce the visibility of the surgical field. Conventionally, the clearing is usually done externally, which requires the clinician to retract the scope from the body, flush the blocked scope to clear it, and insert the flushed scope back into the anatomy. This approach increases procedure time, adds inconvenience to the clinician, and may increase the surgical risk to the patient. While the endoscope remains inserted and in place, in situ clearing of the working channel typically requires high pressure irrigation, which may apply excessive positive pressure to the internal organs.

The present inventors have recognized an unmet need for an endoscopic system: a desired internal pressure can be automatically monitored and stabilized while enabling a user input flow rate (e.g., aspiration flow rate and/or irrigation flow rate) to protect internal organs from pressure-related hazards.

For at least the above reasons, the present inventors have recognized an unmet need for systems and methods: can detect the blocked state in the working channel, unblock the blocked channel, and increase the efficiency, safety and success rate of endoscopic surgery, while maintaining the pressure variations on the anatomical environment under control for the duration of the surgery.

Disclosed herein are systems and methods for in situ clearing of a working channel, such as an irrigation channel or aspiration channel, in an endoscope during endoscopic surgery. According to one aspect of this document, a deoccluding system can use flow information sensed by a flow sensor to detect a channel condition indicative of the presence or absence of an occlusion in a working channel, and unblock the occluded channel by, for example, applying irrigation fluid or suction pressure to the working channel in an alternating manner. The deoccluding system can adjust one or more of an irrigation flow rate or an aspiration flow rate through one or more channels inside the endoscope to keep the pressure of the anatomical environment under control for the duration of the procedure, e.g., to maintain a substantially net zero pressure, or a desired positive pressure or a desired negative pressure specified by the user.

The deoccluding systems and methods according to the various embodiments discussed in this document provide improved solutions for in situ deoccluding of an endoscope during endoscopic surgery. According to various aspects as described herein, the present systems and methods provide endoscopy for a user without the need for repeated insertion and removal of endoscopic accessories and fittings for external flushing and unclogging. In contrast to unclogging via high pressure irrigation, which may put the internal organ at risk of high positive pressure, controlled irrigation and suction, e.g. applied to the same occluded channel in an alternating manner, as discussed in this document, provides environmental stability of the internal organ. Various embodiments of the present deoccluding system can deocclude channels by effectively separating different sized occluding particles that accumulate and occlude the channels while avoiding or minimizing dangerous positive or negative pressure changes on the internal organs. Thus, unwanted material may be removed from the anatomical site safely and more efficiently, while in low-trauma surgery, the surgical time may be reduced, and patient safety and patient recovery time may be improved.

Fig. 1 is a block diagram illustrating an example of a system 100 for clearing a working channel of an endoscope in situ during minimally invasive surgery of a patient while maintaining a pressure of an anatomical environment 101 at an anatomical site at a substantially desired level. The system 100 may include a medical device 110 and optional components. Optional components may include any of the suction source 120, irrigation source 130, user interface 140, sensor circuit 150, or control module 160. In various examples, system 100 may have a modular design that provides enhanced flexibility to allow for easy configuration and replacement of individual components. In an example, the user interface 140, the sensor circuit 150, and the control module 160 may be included in a suction/irrigation control unit. The suction/irrigation control unit may be fluidly coupled to one or more of the device 110, the suction source 120, or the irrigation source 130. The suction/irrigation control unit can accommodate different types of medical devices and different types of irrigation and suction sources. An exemplary suction/irrigation control unit is discussed below with reference to fig. 3A-3B. The suction/irrigation control unit may selectively enable or disable irrigation and/or suction through the working channel 111 and adjust one or more of an irrigation flow rate, an irrigation fluid pressure, a suction flow rate, or a suction pressure. By controlling aspiration and/or irrigation according to various embodiments discussed herein, the obstructed passage may be unblocked and the pressure of the anatomical environment 101 may be maintained at a desired level during surgery.

The medical device 110 may be used for diagnostic, analytical, or therapeutic applications, including, for example, minimally invasive surgical procedures such as endoscopic procedures. By way of example and not limitation, medical device 110 may be used in joint surgery, orthopedic surgery, various ear-nose-throat surgeries including, but not limited to, sinus surgery and tonsillectomy, or combinations thereof. The medical device 110 may be controlled by a user to perform a procedure in an organ in the anatomical environment 101 or to remove organ tissue. Controls of the medical device 110 may include a handpiece or indirect controls, such as via a robotic surgical console or user interface.

Examples of medical device 100 may include a tissue removal device including a blade assembly configured to rotate and/or reciprocate to resect unwanted tissue from a target anatomy. The blade assembly may be driven by a motor that is powered by an energy source internal to the handpiece or alternatively external to the handpiece. The energy source may also perform other functions, such as providing powered irrigation and aspiration to the medical device 110, as will be discussed below. Various blade assemblies may be used including, for example, shavers, debriders, blades, bone drills, or the like. Depending on the blade assembly used, the tissue removal device may be used to shave, cut, abrade, or otherwise remove necrotic, cancerous, damaged, infected, or other unwanted soft tissue, bone, or other anatomical features or objects at or from the target anatomy. An exemplary tissue removal device is discussed below with reference to fig. 2A-2B.

Another example of the medical device 110 may include an endoscope. Examples of endoscopes may include: cystoscopes for examining the bladder; a nephroscope for examining the kidney; a bronchoscope for examining the bronchi; an arthroscope for examining the joint; a colonoscope for examining the colon; a choledochoscope for examining a biliary tract region (e.g., bile duct); a duodenoscope for examining a gastrointestinal region; or laparoscopes for examining the abdomen or pelvis, etc. The endoscope may include a light source for illuminating an anatomical environment at an anatomical site, and an imaging module for generating images or video of the anatomical environment during an endoscopic procedure. Some endoscopes, such as endoscopic tissue removal devices, may include a tissue resection member configured to shave, cut, abrade, or otherwise remove unwanted portions of tissue from a target anatomy. The excised tissue fragments may then be extracted from the anatomical site. Some endoscopes may include an ablation member configured to break up or remove foreign objects, such as crystalline mineral structures, from the anatomical environment. For example, a nephroscope may be at least partially inserted into a kidney. Ultrasonic energy, electromagnetic shock waves or lasers, and other forms of energy may be delivered to the kidney stones to break them into debris or "stone powder," which may then be extracted from the anatomical site. An exemplary endoscope is discussed below with reference to fig. 3A-3B.

The medical device 110 may include one or more working channels 111 for delivering shaved, cut, resected, abraded, or removed tissue, bone or other anatomical features or objects, stones and debris of matter, bodily fluids at the anatomical site, and irrigation fluids, collectively referred to herein as "unwanted matter. The working channel 111 may be selectively coupled to one or more of the suction source 120 (e.g., via a suction port on the medical device 110) or the irrigation source 130 (e.g., via an irrigation port on the medical device 110).

The suction source 120 may be used to aspirate, draw, suck, suction, or otherwise move or remove unwanted material from the anatomical site. The unwanted material may be moved into a receptacle located at the proximal end of the medical device 110, inside the handpiece, or at a location remote from the medical device 110. In an example, the handpiece may contain a container or reservoir for at least temporarily collecting unwanted material before the handpiece is cleaned and the collected material is removed. The suction source 120 may perform the aforementioned functions by generating and applying a vacuum, suction, or negative pressure to the working channel 111 of the medical device 110. In an example, the suction source 120 may be separate from the medical device 110 and connected to the medical device 110 via one or more tubes, wires, or hoses. In another example, the suction source 120 may be included in the medical device 110 or attached to the medical device 110. For example, the suction source 120 may be contained within a tissue removal device or a handpiece of an endoscope. The suction source may be powered by an energy source that also powers the medical device, or may be powered by its own energy source.

The irrigation source 130 may be used to provide irrigation fluid to the working channel 111 to assist in removing unwanted material (e.g., tissue fragments or stone debris) through the working channel 111. The irrigation fluid may also cool the tissue removal device or the cutting element during rotational or reciprocating debridement or resection and help dissipate heat generated during stone fragmentation. The flushing fluid may be gravity fed or pressurized. In an example, the irrigation source may comprise a bag that is elevated relative to the medical device 111 and the anatomical site to produce a gravity-fed irrigation fluid. In another example, the pump may generate a pressurized flushing flow. Irrigation fluid may be provided to and through the external fluid supply tube from an irrigation source 130 or location containing irrigation fluid and drawn into the working channel 111. Under the suction pressure provided by the suction source 120, irrigation fluid may flow with the unwanted material in the proximal direction of the working channel 111 and be removed from the anatomical site.

In an example, a single working channel 111 may be used for both irrigation and aspiration. The control module 160 may controllably enable irrigation and aspiration through the working channel 111 at different times. In another example, the medical device 110 may include two or more separate working channels, such as a suction channel 112 and an irrigation channel 114, as shown in fig. 1. The suction channel 112 may be controllably connected to a suction source 120 to direct suction of unwanted material therethrough. The irrigation channel 114 may be controllably connected to an irrigation source 130 to direct irrigation fluid therethrough. In an example, the aspiration channel 112 can be controllably connected to the irrigation source 130. In an example, the irrigation channel 114 can be controllably connected to a suction source 120. Irrigation and aspiration according to various examples discussed herein may be used to help remove unwanted material, clear one or more working channels, transfer heat generated at an operative field of a tissue site, maintain pressure of an anatomical environment at a desired level, and maintain a desired flow condition in a working channel corresponding to a desired pressure, among other things.

In an example, the aspiration channel 112 and the irrigation channel 114 may be disposed in a parallel orientation along the length of a tubular portion of a handpiece of the medical device 110. In an example, the aspiration channel 112 and the irrigation channel 114 may be disposed coaxially with a common axis, e.g., in a nested configuration. In an example, the medical device 110 includes an outer member and an inner member positioned within the outer member. The suction channel 112 may be located inside the inner member. The irrigation channel 114 may be located on the exterior of the outer member. In some configurations, in addition to or instead of supplying irrigation fluid through irrigation channel 114, irrigation fluid may be supplied through a gap defined between inner and outer members of medical device 110 (hereinafter referred to as an "irrigation gap"). One of the irrigation channel 114 or the irrigation gap may be selectively activated to supply irrigation fluid to the medical device 110. In some examples, both the irrigation channel 114 and the irrigation gap may be enabled to supply irrigation fluid simultaneously. This may advantageously allow the clinician to adjust how much irrigation fluid is used during the procedure. For example, when more tissue fragments or stone debris is produced, or in the event that an occlusion is detected in the channel, both the flush channel 114 and the flush gap may be enabled to provide a greater volume of fluid to the medical device 110.

The control module 160 may be configured to control operation of the medical device 110, including one or more of tissue resection or stone ablation, illumination, imaging, irrigation, and aspiration functions during endoscopic surgery. In an example, the control module 160 may be implemented as part of a microprocessor circuit, such as a special purpose processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other type of processor for processing information, generating control signals to enable, disable, or change the operation of components of the system 100. Alternatively, the microprocessor circuit may be a processor that can receive and execute instructions for performing the functions, methods, or techniques described herein.

The control module 160 may be at least partially implemented in a unit separate from the medical device 110, such as shown in fig. 3A-3B. Alternatively, portions of control module 160 may be integrated into medical device 110 or otherwise attached to medical device 110. In some examples, the control module 160 may include a set of circuits that, alone or in combination, perform the functions, methods, or techniques described herein. In an example, the hardware of a circuit group may include invariantly connected components designed to perform a particular operation (e.g., hard-wired). In an example, the hardware of the circuit group may include variably connected physical components (e.g., execution units, transistors, simple circuits, etc.) to encode instructions for a particular operation, including physically modified (e.g., a magnetically and electrically movable placement of invariant aggregated particles, etc.) computer-readable media. When connecting physical components, the basic electrical characteristics of the hardware components are changed, for example, from an insulator to a conductor or from a conductor to an insulator. The instructions enable embedded hardware (e.g., an execution unit or a loading mechanism) to create members of a circuit group in the hardware via a variable connection to perform portions of a particular operation when operating. Thus, the computer readable medium is communicatively coupled to other components of the circuit group member when the apparatus is operating. In an example, any of the physical components may be used in more than one member of more than one circuit group. For example, in operation, the execution unit may be used in a first circuit of a first circuit group at one point in time and reused by a second circuit in the first circuit group or by a third circuit in the second circuit group at a different time.

As shown in fig. 1, control module 160 may be coupled to user interface 140 and receive user commands from user interface 140 for activating, deactivating, or adjusting one or more functions of medical device 110. The user interface 140 may be at least partially integrated into the medical device 110 or otherwise attached to the medical device 110. Alternatively, the user interface 140 may be separate from the medical device 110, such as the exemplary system shown in fig. 3A-3B. The user interface 140 may be mobile and may be attached to the medical device 110 and the fluid system (e.g., pump, irrigation). In an example, the user interface 140 may include one or more user controls that allow a user (e.g., a clinician) to turn suction on or off, or to adjust the suction flow rate or suction pressure. The user controls may be located on a mobile user interface separate from the medical device 110. Alternatively, the user controls may be located on a medical device 110, such as a tissue removal device, e.g., the device shown in fig. 2A or a handpiece of an endoscope. In response to a user command, the control module 160 may enable or disable suction flow from the suction source 120, or increase or decrease the suction pressure applied to the working channel 111 to achieve a desired suction flow rate. Similarly, the user interface 140 may include one or more user controls that allow a user to turn the flush on or off, or to adjust the flush flow rate or flush fluid pressure (e.g., via a pump). In response to a user command, the control module 160 may enable or disable the irrigation flow from the irrigation source 130, or increase or decrease the irrigation flow rate through the working channel 111.

In some examples, the user controls on the user interface 140 may include depressible flush control buttons that, when repeatedly depressed, cycle through one or more flush water and/or suction levels before flushing and suction are turned off. In some examples, irrigation and aspiration may be controlled together with a single control. Other suitable control elements may also be used, such as a positionable slide, a positionable lever, or a positionable dial that may specify flush water and/or suction levels. In some examples, the user interface 140 may allow the user to select from one of a plurality of specified discrete irrigation or aspiration levels, or alternatively to specify irrigation or aspiration levels in a continuous (e.g., non-discrete) manner.

In addition to or instead of independent control of aspiration and irrigation, the control module 160 may automatically control one of irrigation or aspiration based on the condition of the other of irrigation or aspiration. In an example, control module 160 may automatically turn suction on when the medical device is powered on or when irrigation source 130 supplies irrigation fluid to medical device 110; and control module 160 may automatically turn off suction when the medical device is not powered or when irrigation source 130 stops supplying irrigation fluid to medical device 110. In an example, the control module 160 may automatically adjust the irrigation flow rate or fluid volume in response to the aspiration flow rate (e.g., by activating or deactivating flow in an irrigation gap defined between the inner and outer members). For example, at increased suction (e.g., due to a large amount of unwanted material to be removed), the control module 160 may automatically increase the irrigation flow rate, or supply irrigation fluid via both the irrigation channel 114 and the irrigation gap. Conversely, at reduced suction (e.g., due to small amounts of unwanted material to be removed), the control module 160 may automatically reduce the irrigation flow rate or supply irrigation fluid via only one of the irrigation channel 114 or the irrigation gap, but not both the irrigation channel 114 or the irrigation gap.

The control module 160 may include an occlusion controller 161 configured to detect a channel condition indicative of the presence or absence of an occlusion in the working channel 111 and control one or more of the suction source 120 or irrigation source 130 to provide suction pressure or irrigation fluid, respectively, to unblock the occluded working channel. In an example, the blockage controller 161 can monitor channel conditions and detect channel blockage based on flow information in the working channel 111. The sensor circuitry 150 may include circuitry coupled to a flow sensor positioned inside the working channel 111 and configured to sense a flow rate or volume of liquid moving therein. Flow sensors, such as micro-electromechanical system (MEMS) sensors, may employ various flow measurement techniques. By way of example, and not limitation, a flow sensor may include: a hot air anemometer that measures a transfer rate of heat generated from the heat source; a differential pressure sensor that measures pressure drops across a series of locations; an ultrasonic flow sensor that measures frequency shift or doppler effect of travel/time of flight; electromagnetic sensors that measure changes in the conductance of the fluid indicative of the flow rate, and the like.

The occlusion controller 161 may use flow information sensed by the flow sensor to detect channel occlusions. In an example, the blockage controller 161 may detect a channel blockage in response to a sensed flow rate decreasing below, for example, a first flow rate threshold; and if the sensed flow rate increases and exceeds a second flow rate threshold, the occlusion controller 161 may detect that there is no occlusion or that the occluded working channel was successfully unblocked. In another example, flow rate stability inside a channel may be used to detect channel blockage, for example, when variability in flow rate measurements exceeds a threshold. In some examples, the occlusion controller 161 may detect a channel occlusion by comparing the inflow rate of fluid into the channel and the outflow rate of fluid out of the channel. A mismatch between the inflow and outflow rates, e.g., the outflow rate being significantly lower than the inflow rate (beyond a specified tolerance), indicates that a channel blockage is present.

In the event of a channel occlusion, the occlusion controller 161 may automatically switch from the standard mode of irrigation/aspiration operation discussed above (e.g., where the aspiration source 120 provides aspiration pressure to the aspiration channel 112 and the irrigation source 130 provides a flow of irrigation fluid to the irrigation channel 114) to the unclogging mode of irrigation/aspiration operation. To unblock an obstructed channel, the occlusion controller 161 may alternate between applying irrigation fluid and applying suction pressure to the obstructed channel. Referring now to FIG. 4A, a diagram illustrates a channel clearing technique according to embodiments discussed in this document. Diagram 410 shows fluid-filled channel 411 blocked by obstruction 412 during a standard mode of flushing enabled by flushing source 140. The plugs 412 include different sizes of tissue fragments or stone debris. As shown in diagram 410, smaller particles, such as particle 412A, are located at the proximal end, while larger particles, such as particle 412B, are located at the distal end. Graph 420 illustrates a switch from the standard mode to the deoccluding mode, wherein the occlusion controller 161 fluidly couples the suction source 120 to the proximal portion of the channel 411, activates the suction source 120, and applies suction pressure to the channel 411 for a specified suction duration. The user may adjust the suction pressure and suction duration via the user interface 140. Different sized (and therefore different masses) of occluding particles may respond differently to the applied suction pressure. For example, the smaller particles 412A may move toward the proximal end of the channel and travel a longer distance at a faster speed during (and after) application of suction than the larger particles 412B. Thus, some particles may be removed from the plug 412 and separated from larger particles.

Diagram 430 shows fluid filling channel 411 blocked by obstruction 413 during a standard mode of suction enabled by suction source 120. The particles of plug 413 accumulate differently than plug 412, with smaller particles, such as particles 413A, at the distal end and larger particles, such as particles 413B, at the proximal end. The diagram 440 illustrates a switch from the standard mode to the deoccluding mode, wherein the occlusion controller 161 fluidly couples the irrigation source 140 to the proximal portion of the passage 411, activates the irrigation source 140, and applies irrigation fluid for a specified irrigation duration to flush the passage 411. The user may adjust the flush flow rate or pressure used to pump the flush fluid and the flush duration. Clogging particles of different sizes (and therefore different masses) may respond differently to the flushing fluid. For example, the smaller particles 413A may move toward the distal end of the channel and travel a longer distance at a faster rate during (and after) the application of the rinse than the larger particles 413B. Thus, some particles may be removed from the plug 413 and separated from larger particles.

Additional irrigation and/or suction may be used to extract the separated particles along working channel 411. In an example, one or more of the suction pressure, suction flow rate, irrigation flow rate, or pump pressure used to pressurize the irrigation fluid may be varied (e.g., via the user interface 140) to separate out particles by size. For example, a higher flow rate may be applied to remove larger particles, and a lower flow rate may be applied to remove smaller particles through channel 411.

Fig. 4B to 4C are graphs showing the change of flow in the working channel in the presence of clogging and during the dredging process. Fig. 4B illustrates the flow change in a blocked flush channel, as shown in fig. 4A,

graphs

410 and 420. A flow sensor disposed in the flush channel may be used to measure a flow parameter, such as flow rate. The flow measurement (on the y-axis) has a value between-1 and 1. A positive flow value represents the direction of flow towards the distal end of the suction channel (or towards the anatomical environment 101, see diagram 410 of fig. 4A). A negative flow value represents flow in the opposite direction, i.e., toward the proximal end of the aspiration channel (or away from the anatomical environment 101, see diagram 420 of fig. 4A). The value of the flow measurement is related to the clear flow through the flushing channel. That is, a flow value of "1" represents flow during irrigation of the open channel, and a flow value of "-1" represents flow during aspiration of the open channel.

During the standard mode of flushing of the unblocked flushing passage, the flow sensor can detect a positive flow F0 with a value of approximately "1". As shown, the flow F0 includes fluctuations superimposed on a constant flow, indicating that small debris is aspirated. At T1, the flow rate is reduced to F1 (less than F0). If the drop F0-F1 exceeds the occlusion detection threshold, then occlusion is detected. In this example, F1 is at a level greater than zero, indicating that the channel is not completely blocked, and flushing continues. The particles continue to build up until the flow rate drops to F2 at T2. F2 is approximately zero indicating a primary channel blockage (as shown in graph 410 of fig. 4A). The deocclusion mode can be enabled at T2 or at a time corresponding to a particular (e.g., user-specified) flow condition. Suction may be applied to the occluded passageway, drawing the fluid and substance therein toward the proximal end of the suction passageway (as shown in figure 4A, diagram 420). The flow sensor may sense the negative flow F3. As discussed above with reference to diagram 420 of fig. 4A, suction may break up the obstruction such that smaller sized particles may be separated from the rest of the obstruction and travel a longer distance toward the proximal end of the channel. When the passage is unblocked, suction can continue so that the negative flow F3 can reach an approximate maximum value at T3 ("-1", indicating a substantially unblocked flow). After applying suction for a specified suction period and extracting the dislodged particles from the channel, suction may be stopped at T4. The negative flow rate may then be reduced to a flow F4 of substantially zero. At T5, the standard flush mode is resumed by applying flush fluid to the unblocked passage. When the passage is successfully unblocked and particles are removed from the passage, the flow sensor may sense a positive flow F5 having a value of approximately "1".

Fig. 4C illustrates the flow change in the occluded aspiration channel, as shown in fig. 430 and 440 of fig. 4A. A flow sensor disposed in the aspiration channel may be used to measure a flow parameter, such as flow rate. The flow measurement (on the y-axis) has a value between-1 and 1. A positive flow value represents a flow direction towards the proximal end of the suction channel (or away from the anatomical environment 101, see diagram 430 of fig. 4A). A negative flow value represents flow in the opposite direction, i.e. towards the distal end of the aspiration channel (or towards the anatomical environment 101, see table 440 of fig. 4A). The value of the flow measurement is related to the unobstructed flow through the suction channel. That is, a flow value of "1" represents flow during aspiration of the open channel, and a flow value of "-1" represents flow during irrigation of the open channel.

During the standard mode of suction applied to the unblocked suction channel, the flow sensor may detect a positive flow F0 with a value of approximately "1". As shown, the flow F0 includes fluctuations superimposed on a constant flow, indicating that small debris is aspirated. At T1, the flow rate is reduced to F1 (less than F0). If the drop F0-F1 exceeds the occlusion detection threshold, then occlusion is detected. In this example, F1 is at a level greater than zero, indicating that the channel is not completely blocked, and suction continues. The particles continue to build up until the flow rate drops to F2 at T2. F2 is approximately zero indicating a basic channel blockage (as shown in graph 430 of fig. 4A). The deoccluding mode can be enabled at T2 or at a time corresponding to a particular (e.g., user-specified) flow condition. Irrigation fluid may be injected into the blocked channel toward the distal end of the aspiration channel and toward the anatomical environment (as shown in fig. 4A, diagram 440). The flow sensor may sense the negative flow F3. As discussed above with reference to diagram 440 of fig. 4A, the flushing fluid may break up the obstruction such that smaller sized particles may be separated from the rest of the obstruction and travel a longer distance toward the distal end of the channel. While the channel is unblocked, flushing continues so that the negative flow F3 can reach an approximate maximum value ("-1" indicating a substantially unimpeded flow) at T3. After the flush is applied for the specified flush period, the flush may be stopped at T4. The negative flow rate may then be reduced to a substantially zero flow F4 as the separated particles settle in the channel. At T5, the standard suction mode is restored by applying additional suction to extract the separated particles from the channel. When the passage is successfully unblocked and particles are removed from the passage, the flow sensor may sense a positive flow F5 having a value of approximately "1".

In some examples, suction pressure and irrigation fluid may be repeatedly applied to channel 411 in an alternating manner. This allows for more efficient separation of the particles of the plugs without prior knowledge or determination of the structure of the plugs 412. Furthermore, continuous application of suction and then occasional irrigation can help reduce the incidence of obstruction formation. The sensor circuit 150 can monitor the flow rate while repeatedly applying alternating aspirations and aspirations. The clearing operation may continue as long as the channel blockage remains, including applying irrigation fluid or suction pressure to the blocked channel. When the monitored flow rate increases and exceeds a threshold, the blocked channel is deemed successfully unblocked. The occlusion controller 161 may switch from the deocclusion mode of operation back to the standard mode of irrigation/aspiration operation.

Referring back to fig. 1, the control module 160 may include a pressure controller 162, the pressure controller 162 configured to maintain a pressure of the anatomical environment (also referred to as "ambient pressure") under control, such as to maintain the ambient pressure at a substantially desired pressure level (e.g., a predetermined level, or specified by a user via the user interface 140). In an example, the ambient pressure is considered to be maintained at the desired pressure level if the difference between the ambient pressure measurement (e.g., measured by the pressure sensor) and the desired pressure falls within a tolerance range, such as ± 5% to 10% as a non-limiting example. A desired pressure level to be maintained at an anatomical site of the anatomical environment 101 may be received from the user interface 140. As previously described, suction may cause negative pressure changes at the anatomical site, while irrigation may cause positive pressure changes at the anatomical site. Negative and positive pressure changes may adversely affect internal organs exposed to the anatomical site. Maintaining ambient pressure at a controlled pressure level may improve patient safety and effectively reduce surgical time. In some examples, a desired flow condition may be received, for example, from user interface 140, in addition to or instead of receiving a desired pressure level. The desired flow condition includes information about inflow (e.g., a flow rate of irrigation fluid applied to the anatomical environment) versus outflow (e.g., a flow rate of suction applied to the anatomical environment). The desired flow condition corresponds to a desired pressure to be applied to the anatomical environment. For example, a desired flow condition where the inflow and outflow rates are substantially equal corresponds to a substantially net zero ambient pressure, a desired flow condition where the inflow rate is higher than the outflow rate corresponds to a positive ambient pressure, and a desired flow condition where the inflow rate is lower than the outflow rate corresponds to a negative ambient pressure. The pressure controller 162 may control one or more of the irrigation flow rate or the aspiration flow rate through the one or more working channels to maintain desired flow conditions during the procedure.

The pressure controller 162 may achieve a controlled pressure by automatically activating, deactivating, or adjusting one or more of aspiration or irrigation. The sensor circuit 150 can monitor the pressure of the anatomical environment ("ambient pressure") during endoscopic surgery. In an example, the sensor circuit 150 may be coupled to a pressure sensor to sense ambient pressure or to sense a signal indicative or otherwise related to ambient pressure. Examples of pressure sensors may include resistive pressure sensors, capacitive pressure sensors, piezoelectric pressure sensors, optical pressure sensors, or micro-electromechanical system (MEMS) pressure sensors. In an example, the pressure sensor may be attached to or integrated into a distal end portion of the medical device 110, such as a distal tip of an insertable tubular portion of an endoscope, such that the pressure sensor is in contact with the anatomical environment 101. In an example, the pressure sensor may be positioned at a proximal end location inside the tubular portion of the endoscope, distal from the anatomical environment 101. The control module 160 may receive a desired ambient pressure from the user interface 140 to be maintained during the procedure. The control module 160 may compare the sensed ambient pressure to a desired ambient pressure and adjust one or more of the irrigation flow rate or the aspiration flow rate to drive the ambient pressure toward the desired ambient pressure level.

The pressure controller 162 may maintain a controlled ambient pressure when the system 100 is operating in a standard mode of irrigation/aspiration (when no occlusion is detected in any working channel) and in a deocclusion mode of irrigation/aspiration (when at least one, but not all, of the working channels are occluded). Exemplary systems for regulating ambient pressure via automatic adjustment of aspiration flow rate and/or irrigation flow rate are discussed below with reference to fig. 5 (in the absence of channel blockage) and fig. 6-7 (in the presence of channel blockage).

The user interface 140 may include an output unit, such as a display, to present information collected during endoscopic procedures, including, for example: images of the surgical area (including live video); the operational status of the medical device 110, including the status of the working channel 111; information about the status of the channel, such as blocked channel or successful clearing; as well as ambient pressure as sensed by sensor circuit 150, etc.

Fig. 2A shows a perspective view of a powered tissue removal device 200 as an example of a medical device 110. The powered tissue removal device 200 may include a handpiece 210 and a tubular assembly 222 extending from the handpiece 210. The tubular assembly 222 includes a proximal portion 226 at the handpiece 210 and an opposite distal portion 228. Although the distal portion 228 is shown as a "straight axis" aligned with the remainder of the tubular assembly 222, in some examples, the distal portion 228 may be curved or angled relative to the remainder of the tubular assembly 222 (including the proximal portion 226).

An exemplary configuration of the distal portion 228 is shown in fig. 2B. The tubular assembly 222 includes an outer tubular member 252 and an inner tubular member 254 positioned inside the outer tubular member 252. The outer member 252 includes an outer member window 262. The inner member 254 includes a cutting portion 264 and a suction channel 274 defined within the inner member 254. The inner member 254 or cutting portion 264 includes an inner member window 266 in communication with the suction passage 274.

Powered tissue removal device 200 includes irrigation channel 272 located outside outer member 252 or outside outer member 252. The irrigation channel 272 extends along the length of the outer member 252. The proximal end of the irrigation channel 272 includes a proximal irrigation port 282 in fluid communication with the irrigation source 230, and the distal end of the irrigation channel 272 includes a distal irrigation port 284 attached to the powered tissue removal device 200 or the outer member 252.

The powered tissue removal device 200 may be coupled to an energy source 240, a suction source 220, and an irrigation source 230. The energy source 240 is configured to power the powered tissue removal device 200, the suction source 220, the irrigation source 230, or a combination thereof. The suction source 220, which is an embodiment of the suction source 120, may be in fluid communication with a suction channel 274 defined within the interior of the inner member 254. The suction source 220 is configured to apply suction to or draw a vacuum from the powered tissue removal device 200 via the suction channel 274. The irrigation source 230, which is an embodiment of the irrigation source 130, may be in fluid communication with an irrigation channel 272 located outside of the outer member 252 or outside of the outer member 252. Alternatively or additionally, the irrigation source 230 may be in fluid communication with the gap between the inner and

outer members

254, 252.

The powered tissue removal device 200 includes one or more user controls 224 for operating the powered tissue removal device 200, the energy source 214, the suction source 220, the irrigation source 230, or a combination thereof. By way of example and not limitation, user controls 224, which are embodiments of the user interface 140, may be located at the handpiece 210 to allow easy access and manipulation by the user during surgery. In an example, the user controls 224 may allow the user to manually control one or more of debridement, enable, disable, or adjust irrigation flow rate or aspiration flow, and other irrigation or aspiration parameters.

The powered tissue removal device 200 includes a control module (not shown) located at least partially within the handpiece 210. The control module, which may be an embodiment of the control module 160, may be configured to: operation of powered tissue removal device 200, including one or more of tissue debridement, irrigation, aspiration, and other functions, is controlled in response to user commands from user controls 240. In an example, the control module may detect an occlusion in the working channel (e.g., an integrated irrigation/aspiration channel, or a separate irrigation channel or a separate aspiration channel) based on the sensed flow rate from the working channel and unblock the occluded channel, for example, by alternating between applying irrigation fluid and applying aspiration pressure to the occluded channel. The control module may enable and adjust one or more of the irrigation flow parameters or one or more of the aspiration flow parameters to maintain the pressure of the anatomical environment ("ambient pressure") under control, e.g., to maintain the ambient pressure at substantially the user-specified desired pressure during surgery, as discussed above with reference to fig. 1.

Fig. 3A-3B show, by way of example,

endoscopic systems

300A and 300B, respectively, for use in endoscopic procedures.

Endoscope systems

300A and 300B are embodiments of system 100. Referring to fig. 3A, the system 300A includes an endoscope 310A, a suction source 320, an irrigation source 330, and a suction/irrigation control unit 340. An endoscope 310A, which is an example of a medical device 110, may extend into the sheath, including a tube 311 extending from the distal end to a hub 312. Hub 312 terminates at a proximal end. The endoscope 310 may include an optical port 314 and a visualization port 315. The light port 314 may be used to provide light into the endoscope and out of the tube 311 of the endoscope so that features of interest in the anatomical environment (e.g., excised tissue or stones and materials) are illuminated. For example, the optical port is useful for enhancing visibility when the feature of interest is in low light conditions. The visual port 315 may be used to provide a viewing window that enables a user to view a feature of interest. In an example, the visualization port 315 may be an optical window at the proximal end that provides visual access to a viewing lens at the distal end. In another example, the visual portion 315 can provide a connection point to a camera to capture images or video of the feature of interest and the anatomical environment. The image or video may be output and displayed on a monitor.

The endoscope 310A may include an irrigation/aspiration port 313 for receiving aspiration or irrigation fluid. The irrigation/aspiration port 313 may be located external to the hub 312 or elsewhere on the endoscope 310A, such as at the proximal end of the endoscope 310A. Irrigation/aspiration port 313 opens to a working channel (not shown) inside tube 311. The working channel may be sized, shaped, and configured to deliver irrigation fluid and/or for aspiration. In an example, the same working channel may be used for irrigation and aspiration (also referred to as a unitary irrigation/aspiration channel). In another example, the irrigation channel and the aspiration channel are each disposed within the tube 311.

In an example, the endoscope 310 may be a nephroscope. During use, the flexible distal end portion of the tube 311 may be surgically inserted into the patient's kidney. The proximal portion of the tube 311 may be left outside the patient's body. The interior of tube 311 may include optical fibers that extend along the length of endoscope 310. The optical fiber may be a multimode optical fiber or a single mode optical fiber. A laser external to the nephroscope may generate the laser beam. The laser beam may be coupled into the proximal end of the optical fiber via a suitable connector. The optical fiber can deliver a laser beam to the kidney stone to ablate the kidney stone into fragments. In some examples, the laser beam may have a wavelength corresponding to an absorption spectrum peak of human blood and saline, e.g., 2100nm, 1942nm, etc. In general, it would be beneficial to deliver a laser beam that has significant absorption in blood and saline because such a laser beam can be minimally invasive to surrounding tissue, which can reduce or eliminate damage to tissue at or near the kidney stone. The laser controller may be located on a graspable proximal portion of the endoscope 310. Similar to the user controls 224 that enable manual control of debridement as shown in fig. 2A, the laser controller may enable the user to switch the state of the laser beam between an operational state ("on") and a non-operational state ("off"). In some examples, a user may adjust one or more settings of the laser, such as output power, on the housing of the laser rather than via the laser controller.

The suction/irrigation control unit 340 can provide suction and irrigation to the endoscope 310 during endoscopic surgery while maintaining the pressure of the anatomical environment under control, e.g., maintaining the pressure at substantially a user-specified pressure level (e.g., a user-specified pressure with a tolerance of, e.g., ± 5% to ± 10%). The suction/irrigation control unit 340 may include a pressure monitor (as an embodiment of the sensor circuit 150), a control module (as an embodiment of the control module 160), a pump, a power source. The control module may communicate with a user interface 341 (as an embodiment of the user interface 140) located, for example, outside of the suction/irrigation control unit 340 to control the control module.

The suction source 320 may be connected to a suction/irrigation control unit 340 via an external suction line 326. The suction/irrigation control unit 340 includes a control valve 342, the control valve 342 being configured to control suction between the suction source 320 and the endoscope 310 such that suction may be turned off during all or a portion of the application cycle of irrigation fluid. The irrigation source 330 may be connected to a suction/irrigation control unit 340 via an external irrigation line 336. A pump included in the suction/irrigation control unit 340 may pressurize the irrigation fluid prior to the irrigation fluid entering the endoscope 310 via the irrigation line 336. As shown in fig. 3A, the external suction line 326 and the external irrigation line 336 may be connected together at a common fitting 350, which common fitting 350 may be coupled to a common line 356 for supplying fluid or suction to the endoscope 310 via the irrigation/aspiration port 313.

A control module in the suction/irrigation control unit 340 may be configured to control the operation of the endoscope 310 in response to user commands from the user interface 341. In an example, the control module may detect an occlusion in the working channel (e.g., an integrated irrigation/aspiration channel, a separate irrigation channel, or a separate aspiration channel) based on the sensed flow rate from the working channel and unblock the occluded channel, e.g., by alternating application of irrigation fluid and aspiration pressure. The control module may automatically enable and adjust one or more of the irrigation flow parameters or one or more aspiration flow parameters to maintain the pressure of the anatomical environment ("ambient pressure") under control, e.g., to maintain the ambient pressure at a substantially user-specified pressure level, as discussed above with reference to fig. 1.

The system 330B as shown in fig. 3B is similar to the system 330A and includes an endoscope 310B, a suction source 320, an irrigation source 330, and a control suction/irrigation control unit 340. Similar to endoscope 310A, endoscope 310B may include a tube 311, a hub 312, an optical port 314, and a visualization port 315. However, rather than a single irrigation/aspiration port 313, endoscope 310B includes a separate aspiration port 313A adapted to be in fluid communication with aspiration source 320 and a separate irrigation port 313B adapted to be in fluid communication with irrigation source 330, respectively. The suction source 320 is fluidly coupled to the suction port 313A via an external suction line 326. The flush source 330 is fluidly coupled to the flush port 313B via an external flush line 336. Suction port 313A and irrigation port 313B may each be open to one or more working channels inside tube 311. In the example, the irrigation channel and the aspiration channel are each disposed inside the tube 311. The suction port 313A may be selectively opened to a suction channel or an irrigation channel. Similarly, irrigation port 313B may be selectively open to a suction channel or an irrigation channel inside tube 311.

FIG. 5 is a diagram illustrating an exemplary feedback control pressure regulation system 500 as an embodiment of an ambient pressure control portion of the system 100. The system 500 may be configured to: ambient pressure at the anatomical site is regulated when no channel blockage is indicated, and when the system 500 is operating in a standard mode of irrigation/aspiration (e.g., controlling the aspiration source 120 to provide aspiration pressure to the aspiration channel 112, and controlling the irrigation source 130 to provide a flow of irrigation fluid to the irrigation channel 114). The system 500 may regulate ambient pressure via automatic adjustment of aspiration and/or irrigation flow rates in the respective aspiration and

irrigation channels

112, 114. In an example, the longitudinal axis of the aspiration channel 112 and the longitudinal axis of the irrigation channel 114 may be parallel to each other. In an example, the aspiration channel 112 and the irrigation channel 114 may be coaxially disposed using a common axis, e.g., in a nested configuration. In an example, irrigation and aspiration may be applied at different times through the same working channel, e.g., an integrated irrigation/aspiration channel. Pressure monitor 550 may monitor the pressure of anatomical environment 101 via pressure sensor 352. By way of example and not limitation, the control module 160 may include a Proportional Integral (PI) controller or a Proportional Integral Derivative (PID) controller, among other feedback controllers. The difference, also referred to as an "error", between the sensed pressure (at pressure monitor 550) and the desired pressure may be used to determine the P, I, or D term in the feedback controller.

Depending on the desired pressure (or desired flow condition) provided by the user, the system 500 may operate in a stable pressure mode when the desired pressure is substantially net zero (corresponding to a desired flow condition in which the inflow rate of irrigation fluid applied to the anatomical environment and the outflow rate of suction applied to the anatomical environment are substantially equal); or when the desired pressure is positive or negative (corresponding to an unbalanced desired flow condition between the inflow and outflow rates), the system 500 may operate in a pressure control mode. When operating in the steady pressure mode, the irrigation flow rate or the aspiration flow rate may be manually adjusted by a user, for example, via respective user controls on the user interface 140. During endoscopic surgery, an increase in irrigation flow rate may result in an increase in ambient pressure at the anatomical site, which may be sensed by pressure monitor 550. The control module 160 may responsively enable suction by applying suction pressure to the suction channel 112. Suction may create a negative pressure to counteract the increased pressure created by irrigation. The control module 160 may adjust the aspiration flow rate or aspiration pressure until the pressure increase (due to increased irrigation) is substantially neutralized by the aspiration flow. The ambient pressure may then be driven towards substantially zero and maintained at substantially zero.

Also, an increase in aspiration flow rate may result in a decrease in ambient pressure at the anatomical site. The control module 160 may responsively enable flushing by providing a flow of flushing fluid to the flush channel 114. Irrigation may create positive pressure to counteract the reduced pressure created by aspiration. The control module 160 may adjust the irrigation flow rate until the pressure drop (due to increased suction) is substantially neutralized by the irrigation flow. The ambient pressure may then be driven toward substantially zero and maintained at substantially zero.

In some cases, it is desirable to maintain a positive or negative ambient pressure at the anatomical site. A controlled positive pressure within a safe range may help dilate an anatomical structure (e.g., ureter, kidney, uterus, or other organ) during endoscopic surgery to allow better visualization of the anatomical structure via a scope without tissue damage due to excessive positive pressure. The positive pressure may also prevent tissue or stone debris from becoming lodged in the anatomical structure and may assist in its removal from the anatomical structure. In some cases, maintaining a controlled negative pressure within a safe range during endoscopic surgery may also facilitate the extraction of debris from the anatomy without exposing internal organs to the risk of excessive negative pressure.

When a positive desired ambient pressure is provided by a user, for example, via user interface 140, system 400 may operate in a pressure control mode. The control module 160 may automatically increase the irrigation flow rate through the irrigation channel 114 to increase the positive ambient pressure at the anatomical site. Additionally or alternatively, the control module 160 may automatically decrease the aspiration flow rate through the aspiration channel 112 to reduce negative pressure at the anatomical site. The automatic adjustment of irrigation and/or aspiration may continue until the sensed ambient pressure reaches a level substantially equal to the desired positive pressure.

Likewise, when a negative desired ambient pressure is provided by a user, for example, via the user interface 140, the system 400 may operate in a pressure control mode. The control module 160 may automatically increase the aspiration flow rate through the aspiration channel 112 to increase the negative ambient pressure at the anatomical site. Additionally or alternatively, the control module 160 may automatically decrease the irrigation flow rate through the irrigation channel 114 to reduce positive pressure at the anatomical site. The automatic adjustment of irrigation and/or aspiration may continue until the sensed ambient pressure reaches a level that is substantially the desired negative pressure.

The control module 160 may include a safety mechanism to maintain the pressure of the anatomical environment within a safety range defined by a negative pressure lower limit and a positive pressure upper limit. If the sensed ambient pressure reaches an upper limit of positive pressure, the control module 160 may automatically shut down, reduce, or maintain the current rate of flushing flow to prevent further increases in ambient pressure. Likewise, if the sensed ambient pressure reaches a lower limit of negative pressure, the control module 160 may automatically turn off, decrease, or maintain the current suction flow rate to prevent further reduction in ambient pressure. When the system is operating in pressure control mode, the desired positive pressure and the desired negative pressure received from the user are checked to ensure that they fall within a safe range. In a non-limiting example, the desired positive pressure is 5 pounds force per square inch (psi) (or about 34.5 kilopascals (kPa)), the desired negative pressure is-5 psi (or about-34.5 kPa), and the safety range is between a lower limit of-6 psi (or about 41.4 kPa) and an upper limit of 6psi (or about 41.4 kPa). In an example, if the desired positive pressure received from the user exceeds an upper limit of the positive pressure, or if the desired negative pressure is below a safety limit of the negative pressure, a warning may be issued (e.g., from the user interface 140). With such safety mechanisms, the control module 160 may maintain the ambient pressure at a user-specified level while preventing or minimizing excessive positive or negative pressure exerted on the anatomical environment during surgery.

FIG. 6A is a diagram illustrating an exemplary feedback control pressure regulation system 600 as an embodiment of the system 100. The system 600 may be configured to regulate the pressure of the anatomical environment 101 ("ambient pressure") in the presence of an occlusion in the aspiration channel 112. As discussed above with reference to fig. 4A, when an occlusion in the aspiration channel 112 is detected, the occlusion controller 161 of the controller module 160 may switch from a standard mode (see fig. 5) in which aspiration pressure is applied to the aspiration channel 112 to a deocclusion mode in which the irrigation source 130 is fluidly coupled to the aspiration channel 112 to provide irrigation flow to the aspiration channel 112.

The irrigation flow applied to the suction channel 112 may cause an increase in anatomical pressure at the anatomical site. The pressure controller 162 of the control module 160 may regulate the ambient pressure via automatically adjusting the aspiration flow rate and/or the irrigation flow rate through the aspiration channel 112 and the irrigation channel 114. For example, in response to an increase in ambient pressure (e.g., as sensed by pressure monitor 550), pressure controller 162 may automatically apply suction pressure to irrigation channel 114. If the irrigation channel 114 is not occluded, the applied suction in the irrigation channel 114 can create a negative pressure to the anatomical environment 101 to counteract the pressure increase created by the irrigation through the suction channel 112. In an example, pressure monitor 550 may continuously or periodically monitor the ambient pressure, and pressure controller 162 may adjust the suction flow rate or suction pressure to drive the ambient pressure to a level of the desired pressure.

In an example, the desired pressure is substantially a net zero pressure. The pressure controller 162 may adjust the suction flow rate or suction pressure in the irrigation channel 114 to substantially neutralize the increase in sensed ambient pressure. Thereby, the ambient pressure may be driven towards substantially zero and maintained at substantially zero. In another example, the desired pressure is a positive pressure. The pressure controller 162 may adjust the suction flow rate or suction pressure in the irrigation channel 114 to a level that drives the sensed ambient pressure toward a desired positive pressure level. An example of a desired positive pressure is 5 pounds force per square inch (psi), or about 34.5kPa. In yet another example, the desired pressure is a negative pressure, and the pressure controller 162 may adjust the suction flow rate or suction pressure in the irrigation channel 114 to a level that drives the sensed ambient pressure toward the desired negative pressure level. An example of a desired negative pressure is-5 psi, or equivalently about-34.5 kPa.

As discussed above with reference to fig. 3A-3B, unclogging may involve alternating between applying suction and applying irrigation to the obstructed passage. Fig. 6B is a timing diagram for enabling irrigation/aspiration in the aspiration channel (as shown in fig. 7A) when an occlusion occurs in the aspiration channel 112. To unblock the suction channel, an irrigation is applied to the suction channel for a duration t1 ("irrigation duration"). In a transition period t _d Thereafter, suction pressure is applied to the suction channel for a duration t2 ("suction duration"). Transition period t _d Enabling clogging particles of different sizes and masses to travel different distances along the suction channel facilitates particle separation and channel clearing. Irrigation may induce a positive anatomical pressure (+ PA) 661 at the anatomical site, while aspiration may induce a negative pressure (-PA) 662 at the anatomical site.

Fig. 6C is a timing diagram for enabling irrigation/suction in the irrigation channel during the clearing process to achieve pressure control at the anatomical site, e.g., to maintain a desired anatomical pressure. During t1, the pressure controller 162 may enable suction of the irrigation channel 114, which may generate a negative dissection pressure (-PA) 671 to counteract the positive dissection pressure (+ PA) 661 at the dissection site. During t2, the pressure controller 162 may enable flushing of the flush channel 114, which may generate a positive anatomical pressure (+ PA) 672 to counteract a negative anatomical pressure (-PA) 662 at the anatomical site. Thereby, the pressure of the anatomical environment may be maintained at a desired level while unclogging the obstructed suction channel.

When the flow monitor 650 senses an increase in flow rate through the aspiration channel 112 via the flow sensor 652, it is determined that the occluded channel was successfully unblocked. The occlusion controller 161 may switch back to the standard mode of irrigation/aspiration operation (e.g., control the aspiration source to apply aspiration pressure to the aspiration channel and control the irrigation source to provide irrigation fluid to the irrigation channel). The pressure controller 162 may operate suction and irrigation to maintain ambient pressure under control, as discussed above with reference to fig. 5.

FIG. 7A is a diagram illustrating an exemplary feedback control pressure regulation system 700 as an embodiment of the system 100. The system 700 may be configured to adjust the pressure exerted on the anatomical environment 101 ("ambient pressure") in the presence of an occlusion in the irrigation channel 114. As discussed above with reference to fig. 4A, when an occlusion in the irrigation channel 112 is detected, the occlusion controller 161 of the controller module 160 may switch from a standard mode of providing irrigation fluid to the irrigation channel 114 to a deoccluding mode in which the suction source 120 may be fluidly coupled to the irrigation channel 114 to suction the occluded irrigation channel 114 or to draw a vacuum on the occluded irrigation channel 114.

The suction pressure applied to the irrigation channel 114 may cause a pressure reduction at the anatomical site of the anatomical environment 101. The pressure controller 162 of the control module 160 may regulate the ambient pressure via automatically adjusting the suction and/or irrigation flow rates through the suction channel 112 and the irrigation channel 114. For example, in response to a decrease in ambient pressure (which may be sensed by pressure monitor 550), pressure controller 162 may automatically enable irrigation fluid to flow into aspiration channel 112. If the aspiration channel 112 is not occluded, the application of irrigation fluid in the aspiration channel 112 can create a positive pressure to counteract the pressure drop at the anatomical environment 101 created by the aspiration through the irrigation channel 114. In an example, the pressure monitor 550 may continuously or periodically monitor the ambient pressure, and the pressure controller 162 may adjust the irrigation flow rate to drive the ambient pressure toward a level of the desired pressure.

In an example, the desired pressure is substantially a net zero pressure. The pressure controller 162 may adjust the irrigation flow rate through the aspiration channel 112 to a level that substantially neutralizes the reduction in sensed ambient pressure. The ambient pressure, as sensed by the pressure sensor 550, may then be driven toward substantially zero, or maintained at substantially zero. In another example, the desired pressure is a positive pressure. The pressure controller 162 may adjust the irrigation flow rate through the aspiration channel 112 to a level that drives the sensed ambient pressure toward a desired positive pressure level. In yet another example, the desired pressure is a negative pressure, and the pressure controller 162 may adjust the irrigation flow rate through the aspiration channel 112 to a level that drives the sensed ambient pressure toward the desired negative pressure level.

Fig. 7B is a timing diagram for enabling irrigation/aspiration in the irrigation channel (as shown in fig. 7A) when an occlusion occurs in the irrigation channel 114. To unblock the irrigation channel, suction is applied to the irrigation channel for a duration t3 ("suction duration"). In a transition period t _d Thereafter, a flushing pressure is applied to the flushing channel for a duration t4 ("flushing duration"). Transition period t _d Enabling different sizes and masses of clogging particles to travel different distances along the flushing path, which aids in particle separation and channel clearing. Suction may induce a negative anatomical pressure (-PA) 761 at the anatomical site, while irrigation may induce a positive anatomical pressure (+ PA) 762 at the anatomical site.

Fig. 7C is a timing diagram for enabling irrigation/suction in the suction channel during the deoccluding procedure to achieve pressure control at the anatomical site, e.g., to maintain a desired anatomical pressure. During t3, the pressure controller 162 may enable irrigation of the aspiration channel 112, which may generate a positive anatomical pressure (+ PA) 771 to counteract the negative anatomical pressure (-PA) 761 at the anatomical site. During t4, the pressure controller 162 may enable suction to the suction channel 112, which may generate a negative anatomical pressure (-PA) 772 to counteract the positive anatomical pressure (+ PA) 762 at the anatomical site. Thereby, the pressure of the anatomical environment may be maintained at a desired level while unclogging the obstructed irrigation channel.

When the flow monitor 650 senses an increase in flow rate through the aspiration channel 112 via the flow sensor 652, it is determined that the occluded channel was successfully unblocked. The occlusion controller 161 may switch back to the standard mode of irrigation/aspiration operation (e.g., control the aspiration source to apply aspiration pressure to the aspiration channel and control the irrigation source to provide irrigation fluid to the irrigation channel). The pressure controller 162 may operate the aspiration and irrigation to maintain the ambient pressure under control, as discussed above with reference to fig. 5.

Fig. 8 is a flow chart illustrating a method 800 for clearing a working channel in a medical device in situ during minimally invasive surgery, such as endoscopic surgery. Medical devices include tubular sections that can be inserted inside hollow organs or body cavities to assist in medical diagnosis or surgical treatment. Examples of medical devices may include tissue removal devices such as shown in fig. 2A-2B or endoscopes such as shown in fig. 3A-3B, and the like. The medical device may include one or more working channels configured to provide irrigation fluid to the anatomical site and to transport tissue fragments, stones or masses, bodily fluids, and irrigation fluid (collectively referred to herein as unwanted matter) away from the anatomical site. The working channel may be at least partially located inside the tubular portion of the medical device. In an example, the working channel is an integrated irrigation/aspiration channel that is controllably (e.g., at different times) used for irrigation and aspiration. In another example, the working channel may comprise separate irrigation and aspiration channels disposed within the tubular portion of the medical device. According to various embodiments discussed in this document, the irrigation channel and the aspiration channel may each receive irrigation fluid or aspiration pressure, for example under automatic control by a controller unit, to perform different tasks or to achieve different functions during endoscopic surgery.

The method 800 includes one or more processes of operating a deoccluding system, such as the system 100 or a variation thereof (e.g., one of the

systems

200, 300A or 300B). Although the processes of method 800 are depicted in a flowchart, they need not be performed in a particular order. In various examples, some of the processes may be performed in a different order than that shown herein.

At 810, a flow rate through the working channel can be sensed using a flow sensor, which can be positioned inside the working channel of the medical device. Examples of flow sensors may include a hot air anemometer that measures the rate of transfer of heat generated from a heat source, a differential pressure sensor that measures the pressure drop across a series of locations, an ultrasonic flow sensor that measures the doppler effect or travel/time-of-flight of a frequency shift, an electromagnetic sensor that measures the conductance change of a fluid indicative of flow rate, and so forth. At 820, a channel condition indicative of the presence or absence of an occlusion in the working channel may be detected based on the sensed flow rate, for example using the occlusion controller 161. In an example, a channel blockage may be detected in response to a flow rate decrease, e.g., below a first flow rate threshold. If the sensed flow rate increases and exceeds the second flow rate threshold, successful clearing of the working channel absent clogging or blockage may be detected. In an example, the first flow rate threshold or the second flow rate threshold may each be relative to (e.g., be a particular percentage of) a reference flow rate, such as a reference flow rate measured in an unplugged channel.

If the flow rate sensed at 830 indicates an occlusion in the working channel, a unclogging mode of irrigation/aspiration operation is enabled at 840 to unclog the occluded working channel. When separate irrigation and aspiration channels are used in the medical device, the deoccluding mode includes applying a flow of irrigation fluid to the aspiration channel, and/or applying aspiration pressure to the irrigation channel. This is in contrast to the standard mode of irrigation/aspiration operation, in which the aspiration source provides aspiration pressure to the aspiration channel and the irrigation source provides a flow of irrigation fluid to the irrigation channel. In an example, at 840, the deoccluding mode can include alternating between flushing the occluded channel and suctioning. As discussed above with reference to fig. 4A, the occlusion controller 161 may controllably activate a suction source (e.g., suction source 120) to provide a suction pressure to the occluded working channel for a specified suction duration (as shown in block 420 of fig. 4A). Alternatively or additionally, the occlusion controller 161 may activate the irrigation source (e.g., irrigation source 140) to apply a flow of irrigation fluid to the blocked working channel for a specified irrigation duration (as shown in block 440 of fig. 4A). The suction pressure, suction flow rate, irrigation flow rate, or pump pressure for pressurizing the irrigation fluid may be adjusted by the user.

Different sized (and therefore different masses) of occluding particles may respond differently to aspiration or flushing of irrigation fluid. As shown in fig. 4A, suctioning, rinsing, or alternating between suctioning and rinsing can help to remove smaller particles from the occluding block and separate from the rest of the occlusion, because smaller particles can move at a faster rate and travel a longer distance along the suction or fluid flow direction than larger particles. By applying an additional suction or flushing flow to the working channel, the separated particles can be extracted along the working channel more easily and efficiently. In an example, one or more of the aspiration pressure, aspiration flow rate, irrigation flow rate, or pump pressure may be varied to separate out particles by size. For example, a higher flow rate may be applied to remove larger particles, and a lower flow rate may be applied to remove smaller particles through the channel.

The flow rate may be continuously or periodically monitored 810 during the deoccluding process. When the monitored flow rate increases and exceeds the threshold at 830, the blocked channel is deemed to be successfully unblocked. The unclogging mode of operation may then be switched back to the standard mode of irrigation/aspiration operation.

Fig. 9 is a flow diagram illustrating a method 900 for clearing a working channel of a medical device in situ while maintaining a pressure of the anatomical environment ("ambient pressure") under control, such as maintaining the ambient pressure at a substantially user-specified pressure level. The process of controlling ambient pressure may be implemented in and performed by a pressure controller, such as pressure controller 162. The processes of method 900 need not be performed in a particular order. For example, some steps may be performed in a different order than that shown herein.

Method 900 includes steps 910 through 940 for detecting blockages in working channels and clearing the blocked channels, similar to steps 810 through 840 of method 800. Method 900 also includes steps 950-980 to adjust ambient pressure during a procedure (e.g., endoscopic procedure) with or without channel blockage. As previously described, aspiration may result in negative pressure changes at the anatomical site, while irrigation may result in positive pressure changes at the anatomical site. Negative pressure variations and positive pressure variations may adversely affect internal organs exposed to the anatomical site. Maintaining ambient pressure at a controlled pressure level can increase patient safety and effectively shorten procedure time.

The regulation of the ambient pressure may be achieved by automatically adjusting the suction flow rate and/or the irrigation flow rate in one or more working channels. Specifically, at 950, ambient pressure may be sensed using a pressure sensor. The pressure sensor may be attached to or integrated into a distal portion of the medical device such that the sensor is in contact with the anatomical environment. Examples of pressure sensors may include resistive pressure sensors, capacitive pressure sensors, piezoelectric pressure sensors, optical pressure sensors, or micro-electromechanical system (MEMS) pressure sensors.

At 960, the sensed tissue pressure may be compared to a desired pressure, for example, provided by a user via the user interface 140. The desired pressure represents the pressure to be maintained at the anatomical environment during surgery. In one example, the desired pressure is substantially a net zero pressure. In another example, the desired pressure is a positive pressure. In yet another example, the desired pressure is a negative pressure. Maintaining a controlled positive pressure within a safe range may help dilate an anatomical structure (e.g., ureter, kidney, or other organ) during endoscopic surgery to allow better visualization of the anatomical structure through a scope without tissue damage due to excessive positive pressure. The positive pressure may also prevent tissue or stone debris from becoming lodged in the anatomical structure and assist in their removal from the anatomical structure. In some cases, maintaining a controlled negative pressure within a safe range during endoscopic surgery may also facilitate the extraction of debris from the anatomy without risking excessive negative pressure on internal organs.

If the sensed pressure does not reach a level that is substantially the desired pressure (i.e., within a tolerance range, such as ± 5% to 10% of the desired pressure) at 960, one or more of an irrigation flow rate or an aspiration flow rate through one or more working channels may be adjusted, such as using the pressure controller 162, at 970 to drive the ambient pressure toward the level of the desired pressure. In some examples, a desired flow condition may be received, for example, from user interface 140, in addition to or instead of a desired pressure level. The desired flow condition includes information about inflow (e.g., a flow rate of irrigation fluid applied to the anatomical environment) versus outflow (e.g., a flow rate of suction applied to the anatomical environment) and corresponds to a desired pressure to be applied to the anatomical environment. One or more of the irrigation flow rate or the aspiration flow rate through the one or more working channels may be varied to maintain a desired flow condition during the procedure.

When no blockage is detected in any of the working channels, or the blocked channel has been successfully unblocked, the pressure control process at 970 can be performed by the standard mode of irrigation/aspiration operation. As described above with reference to fig. 5, suction applied to the suction channel may create a negative pressure of the anatomical environment, which may offset the increase in ambient pressure created by the increased irrigation flow rate. The aspiration flow rate or aspiration pressure may be adjusted until the sensed increase in pressure (e.g., caused by increased irrigation) is substantially neutralized by the aspiration flow, thereby producing a desired substantially net zero pressure; or until the sensed ambient pressure reaches a level substantially equal to the desired positive pressure or the desired negative pressure. Similarly, the flow of irrigation fluid provided to the irrigation channel may generate a positive pressure of the anatomical environment, which may offset the reduction in ambient pressure generated by the aspiration. The irrigation flow rate may be adjusted until the sensed decrease in pressure (e.g., caused by increased suction) is substantially neutralized by the irrigation flow, thereby producing a desired substantially net zero pressure; or until the sensed ambient pressure reaches a level substantially equal to the desired positive pressure or the desired negative pressure.

The pressure control process at 970 may be performed by a deoccluding mode of irrigation/aspiration operation when at least one, but not all, of the working channels are occluded. Fig. 6A shows an example where the suction channel is occluded and the irrigation channel is not occluded. As discussed therein, a flow of irrigation fluid may be applied to the aspiration channel to unblock the occluded aspiration channel. This may produce an increase in ambient pressure as may be detected by the pressure sensor. Suction pressure may be applied to the irrigation channels, which may create a negative pressure to counteract the pressure increase at the anatomical environment. The aspiration flow rate or aspiration pressure in the irrigation channel may be adjusted until the sensed increase in pressure (caused by increased irrigation in the occluded aspiration channel) is substantially neutralized by the aspiration flow, thereby producing a desired substantially net zero pressure; or until the sensed ambient pressure reaches a level substantially equal to the desired positive pressure or the desired negative pressure.

In another example where the irrigation channel is occluded and the suction channel is not occluded, suction pressure may be applied to the irrigation channel to unblock the occluded irrigation channel. This may produce a reduction in ambient pressure. As discussed above with reference to fig. 7A, a flow of irrigation fluid may be applied to the aspiration channel, which may create a positive pressure to counteract the negative increase at the anatomical environment. The irrigation flow rate may be adjusted until the sensed decrease in pressure (caused by increased suction in the obstructed irrigation channel) is substantially neutralized by the irrigation flow, thereby producing a desired substantially net zero pressure; or until the sensed ambient pressure reaches a level substantially equal to the desired positive pressure or the desired negative pressure.

At 980, it is checked whether the procedure is complete. If the procedure is not complete, the flow rate sensing and venting processes 910 through 940 and the pressure control processes 950 through 980 may continue.

As described in

methods

800 and 900, controlled irrigation and aspiration, including alternating between applying irrigation fluid and applying aspiration pressure to the same occluded channel, can effectively unblock the channel by separating the different sized debris that accumulate to occlude the channel. As described in method 900, pressure control by applying irrigation and/or suction in one or more working channels may effectively avoid or minimize excessive positive or negative pressure exerted on an internal organ during endoscopic surgery in the presence and absence of channel blockage. Thus, the total surgical time may be shortened and patient safety may be improved.

Additional notes

The foregoing detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are also referred to herein as "examples. Such examples may include elements in addition to those shown or described. However, the inventors also contemplate examples providing only those elements shown or described. Moreover, the inventors also contemplate examples using any combination or permutation of those elements (or one or more aspects thereof) shown or described with respect to a particular example (or one or more aspects thereof) shown or described herein or with respect to other examples (or one or more aspects thereof).

In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independently of any other instances or usages of "at least one" or "one or more". In this document, unless otherwise indicated, the term "or" is used to refer to a non-exclusive or, such that "a or B" includes "a but not B," B but not a, "and" a and B. In this document, the terms "including" and "in which" are used as the plain chinese equivalents of the respective terms "comprising" and "in which". Also, in the appended claims, the terms "comprising" and "including" are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements other than those listed after such term in a claim is still considered to fall within the scope of that claim. Furthermore, in the appended claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

The above description is intended to be illustrative and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments may be used, for example, by one of ordinary skill in the art in view of the above description. The abstract is provided to comply with 37c.f.r. § 1.72 (b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Furthermore, in the foregoing detailed description, various features may be combined together to organize the disclosure. This should not be construed as an intention: the features of the disclosure that are not claimed are essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the detailed description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments may be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

1. A system for clearing at least one working channel of a medical device during a procedure on a patient, the system comprising:

a flow sensor configured to sense a flow rate through at least one working channel of the medical device; and

a control module configured to:

detecting a channel condition indicative of the presence or absence of a blockage in the at least one working channel based on the sensed flow rate; and

in response to the detected channel status indicating the presence of an occlusion in the at least one working channel, alternating between applying a flushing flow and applying a suction flow to the at least one working channel, the application of the flushing flow and the application of the suction flow being separated by a specified or adjustably specifiable time interval to allow separation of the occluding particles by movement.

2. The system of claim 1, wherein the control module is configured to: alternating between the application of the rinsing flow and the application of the suction flow as long as the detected channel status indicates the presence of a blockage in the at least one working channel.

3. The system of any one of claims 1-2, wherein the control module is configured to: applying the irrigation flow to the at least one working channel using a first adjustable pressure or a first adjustable restriction, and applying suction to the at least one working channel at a second adjustable pressure or a second adjustable restriction.

4. The system of any one of claims 1 to 3, wherein the control module is configured to: the irrigation flow is applied to the at least one working channel for a first specified or adjustably specifiable duration and suction is applied to the at least one working channel for a second specified or adjustably specifiable duration.

5. The system of any of claims 1-4, wherein the control module is configured to:

detecting a blockage in the at least one working channel in response to the sensed flow rate decreasing below a first threshold; and

detecting an absence of a blockage in the at least one working channel in response to the sensed flow rate increasing above a second threshold.

6. The system of any one of claims 3 to 5, further comprising a pressure sensor configured to sense a pressure of an anatomical environment at the anatomical site of the patient, wherein the control module is configured to:

receiving a desired pressure to be applied to an anatomical environment at an anatomical site in the patient; and

adjusting one or more of the irrigation flow or the aspiration flow to maintain the sensed pressure of the anatomical environment at a level substantially at the desired pressure.

7. The system of any one of claims 3 to 5, further comprising a pressure sensor configured to sense a pressure of an anatomical environment at the anatomical site of the patient, wherein the control module is configured to:

receiving a desired flow condition in the at least one working channel, the desired flow condition being indicative of a relative condition between the irrigation flow and the aspiration flow and corresponding to a desired pressure to be applied to the anatomical environment; and

adjusting one or more of a flushing flow or a suction flow to maintain the desired flow conditions in the at least one working channel.

8. The system of any one of claims 6 to 7, wherein the at least one working channel comprises a suction channel and an irrigation channel, and wherein the control module is configured to:

fluidly coupling an irrigation source to one of the irrigation channel or the aspiration channel to provide the irrigation flow to the one of the irrigation channel or the aspiration channel at an adjustable pressure or an adjustable flow rate; and

fluidly coupling a suction source to the other of the irrigation channel or the suction channel to provide the suction flow to the other of the irrigation channel or the suction channel at an adjustable pressure or an adjustable flow rate.

9. The system of claim 8, wherein the control module is configured to:

controlling the irrigation source to provide an irrigation flow to the aspiration channel in response to the presence of an occlusion in the aspiration channel;

in response to a sensed increase in pressure of the anatomical environment, controlling the suction source to apply suction flow to the irrigation channel to maintain the sensed pressure at substantially the desired pressure level; and

in response to an absence of an occlusion in the aspiration channel, controlling the aspiration source to apply an aspiration flow to the aspiration channel, and controlling the irrigation source to provide an irrigation flow to the irrigation channel.

10. The system of claim 8, wherein the control module is configured to:

controlling the suction source to apply a suction flow to the irrigation channel in response to a presence of an occlusion in the irrigation channel;

in response to a sensed decrease in pressure of the anatomical environment at the anatomical site, controlling the irrigation source to provide irrigation flow to the aspiration channel to maintain the sensed pressure at substantially the desired pressure level; and

in response to an absence of an occlusion in the irrigation channel, controlling the suction source to apply a suction flow to the suction channel and controlling the irrigation source to provide an irrigation flow to the irrigation channel.

11. The system of claim 9, wherein the desired pressure is a substantially net zero pressure, and wherein the control module is configured to: in response to a sensed increase in pressure, controlling the suction source to apply suction flow to the irrigation channel at an adjustable flow rate to substantially neutralize the sensed increase in pressure.

12. The system of claim 10, wherein the desired pressure is a substantially net zero pressure, and wherein the control module is configured to: in response to a sensed decrease in pressure, controlling the irrigation source to provide irrigation flow to the aspiration channel at an adjustable flow rate to substantially neutralize the sensed decrease in pressure.

13. The system of claim 9, wherein the desired pressure is a positive pressure, and wherein the control module is configured to: in response to the increase in sensed pressure, controlling the suction source to apply suction to the irrigation channel at an adjustable flow rate to maintain the sensed pressure at substantially a desired level of positive pressure.

14. The system of claim 10, wherein the desired pressure is a positive pressure, and wherein the control module is configured to: in response to a decrease in the sensed pressure, controlling the irrigation source to provide irrigation flow to the aspiration channel at an adjustable flow rate to maintain the sensed pressure at substantially a desired level of positive pressure.

15. The system of claim 9, wherein the desired pressure is a negative pressure, and wherein the control module is configured to: in response to the increase in sensed pressure, controlling the suction source to apply suction to the irrigation channel at an adjustable flow rate to maintain the sensed pressure at substantially the desired level of negative pressure.

16. The system of claim 10, wherein the desired pressure is a negative pressure, and wherein the control module is configured to: in response to a decrease in the sensed pressure, controlling the irrigation source to provide irrigation flow to the aspiration channel at an adjustable flow rate to maintain the sensed pressure at substantially a desired level of negative pressure.

17. An endoscopic surgical system, comprising:

an endoscope comprising an imaging module, a surgical module, and at least one working channel configured to pass an irrigation or aspiration flow;

a user input configured to receive a desired pressure from a user to be applied to an anatomical environment at an anatomical site of a patient;

a flow sensor configured to sense a flow rate through at least one working channel of the endoscope;

a pressure sensor configured to sense a pressure of an anatomical environment at the anatomical site; and

a control module configured to:

detecting a channel condition using the sensed flow rate, the channel condition indicating the presence or absence of a blockage in the at least one working channel;

alternating between applying a flushing flow and applying a suction flow to the at least one working channel in response to the detected channel status indicating the presence of an occlusion in the at least one working channel and as long as the detected channel status indicates the presence of an occlusion in the at least one working channel, the applying of the flushing flow and the applying of the suction flow being separated by a specified or adjustably specifiable time interval to allow separation of the occluding particles by movement; and

adjusting one or more of a flushing flow or a suction flow through the at least one working channel to maintain the sensed pressure at a level substantially at the desired pressure.

18. A method of clearing at least one working channel of a medical device during a procedure on a patient, the method comprising:

sensing a flow rate through at least one working channel of the medical device via a flow sensor;

detecting, via a control module, a channel condition using the sensed flow rate, the channel condition indicating a presence or absence of a blockage in the at least one working channel; and

19. The method of claim 18, wherein alternating between the application of the irrigation flow and the application of the aspiration flow continues as long as the detected channel condition indicates a blockage in the at least one working channel.

20. The method of any of claims 18 to 19, wherein detecting the channel state comprises:

21. The method of any of claims 18 to 20, comprising:

receiving, via a user input, a desired pressure to be applied to an anatomical environment at an anatomical site in the patient;

sensing, via a pressure sensor, a pressure of an anatomical environment at the anatomical site; and

adjusting one or more of the irrigation flow or the aspiration flow through the at least one working channel to maintain the sensed pressure at substantially the desired pressure level.

22. The method of claim 21, comprising:

receiving a desired flow condition in the at least one working channel, the desired flow condition being indicative of a relative condition between the irrigation flow and the aspiration flow and corresponding to the desired pressure to be applied to the anatomical environment; and

adjusting one or more of the irrigation flow or the aspiration flow through the at least one working channel to maintain the desired flow condition in the at least one working channel.

23. The method of any one of claims 21 to 22, wherein the at least one working channel comprises a suction channel and an irrigation channel, the method comprising:

controlling an irrigation source to provide an irrigation flow to the aspiration channel in response to the presence of an occlusion in the aspiration channel;

in response to a sensed increase in pressure of the anatomical environment at the anatomical site, controlling a suction source to apply suction flow to the irrigation channel to maintain the sensed pressure at substantially the desired pressure level; and

in response to an absence of an occlusion in the aspiration channel, controlling the aspiration source to apply an aspiration flow to the aspiration channel and controlling the irrigation source to provide an irrigation flow to the irrigation channel.

24. The method of any one of claims 21 to 23, wherein the at least one working channel comprises a suction channel and an irrigation channel, the method comprising:

controlling a suction source to apply a suction flow to the irrigation channel in response to the presence of an occlusion in the irrigation channel;

in response to a sensed decrease in pressure of the anatomical environment at the anatomical site, controlling an irrigation source to provide irrigation flow to the aspiration channel to maintain the sensed pressure at substantially the desired pressure level; and