SYSTEM AND METHOD FOR TREATMENT OF NON-VENTILATING MIDDLE EAR BY PROVIDING A GAS PATHWAY THROUGH THE NASOPHARYNX
Methods and devices for providing a gas pathway between the nasopharynx and the Eustachian tube are provided. One device may include a lumen with a valve. A portion of the valve may be tethered to adjacent muscle. Another portion of the valve may be tethered to adjacent cartilage. When the muscle contracts the valve may open through movement of the tethers, and provide a gas pathway between the nasopharynx and the Eustachian tube.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/165,448, filed Mar. 31, 2009, the full disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTIONThe present invention is related to methods and systems for accessing, diagnosing and/or treating target tissue regions within the middle ear and the Eustachian tube.
Referring to
The Eustachian tube 26 is a narrow, one-and-a-half inch long channel connecting the middle ear 14 with the nasopharynx 30, the upper throat area just above the palate, in back of the nose. The Eustachian tube 26 functions as a pressure equalizing valve for the middle ear 14 which is normally filled with air. When functioning properly, the Eustachian tube 26 opens for a fraction of a second periodically (about once every three minutes) in response to swallowing or yawning. In so doing, it allows air into the middle ear 14 to replace air that has been absorbed by the middle ear lining (mucous membrane) or to equalize pressure changes occurring on altitude changes. Anything that interferes with this periodic opening and closing of the Eustachian tube 26 may result in hearing impairment or other ear symptoms.
Obstruction or blockage of the Eustachian tube 26 results in a negative middle ear pressure 14, with retraction (sucking in) of the eardrum 22. In adults, this is usually accompanied by some ear discomfort, a fullness or pressure feeling and may result in a mild hearing impairment and head noise (tinnitus). There may be no symptoms in children. If the obstruction is prolonged, fluid may be drawn from the mucous membrane of the middle ear 14, creating a condition we call serous otitis media (fluid in the middle ear). This occurs frequently in children in connection with an upper respiratory infection and accounts for the hearing impairment associated with this condition.
A lining membrane (mucous membrane) of the middle ear 14 and Eustachian tube 26 is connected with, and is the same as, the membrane of the nose 42, sinuses 44 and throat 32. Infection of these areas results in mucous membrane swelling which in turn may result in obstruction of the Eustachian tube 26. This is referred to as serous otitis media, i.e., essentially a collection of fluid in the middle ear 14 that can be acute or chronic, usually the result of blockage of the distal opening 28 of the Eustachian tube 26 which allows fluid to accumulate in the middle ear 14. In the presence of bacteria, this fluid may become infected leading to an acute suppurative otitis media (infected or abscessed middle ear). When infection does not develop, the fluid remains until the Eustachian tube 26 again begins to function normally, at which time the fluid is absorbed or drains down the tube into the throat 32 through the Eustachian tube opening 28.
Chronic serous otitis media may result from longstanding Eustachian tube blockage, or from thickening of the fluids so that it cannot be absorbed or drained down the Eustachian tube 26. This chronic condition is usually associated with hearing impairment. There may be recurrent ear pain, especially when the individual catches a cold. Fortunately, serous otitis media may persist for many years without producing any permanent damage to the middle ear mechanism. The presence of fluid in the middle ear 14, however, makes it very susceptible to recurrent acute infections. These recurrent infections may result in middle ear damage.
When the Eustachian tube 26 contains a build-up of fluid, a number of things will occur. First, the body absorbs the air from the middle ear 14, causing a vacuum to form which tends to pull the lining membrane and ear drum 22 inward causing pain. Next, the body replaces the vacuum with more fluid which tends to relieve the pain, but the patient can experience a fullness sensation in the ear 10. Treatment of this condition with antihistamines and decongestants can take many weeks to be fully effective. Finally, the fluid can become infected which is painful and makes the patient feel ill and may not be able to hear well. If the inner ear 14 is affected, the patient may feel a spinning or turning sensation (vertigo). The infection is typically treated with antibiotics.
However, even if antihistamines, decongestants and antibiotics are used to treat an infection or other cause of fluid build-up in the middle ear 14, these treatments will typically not immediately resolve the pain and discomfort caused by the buildup of fluid in the middle ear 14, i.e., the most immediate relief will be felt by the patient if the fluid can be removed from the Eustachian tube 26.
Antibiotic treatment of middle ear infections typically results in normal middle ear function within three to four weeks. During the healing period, the patient can experience varying degrees of ear pressure, popping, clicking and fluctuation of hearing, occasionally with shooting pain in the ear. Resolution of the infection occasionally leaves the patient with uninfected fluid in the middle ear 14, localized in the Eustachian tube 26.
Fluid build-up caused by these types of infections has been treated surgically in the past. The primary objective of surgical treatment of chronic serous otitis media is to reestablish ventilation of the middle ear, keeping the hearing at a normal level and preventing recurrent infection that might damage the eardrum membrane and middle ear bones.
For example, as shown in
Another method of relieving the pressure in the middle ear 14 is shown in
The methods of
In connection with the above surgical treatments of
Another method for clearing the middle ear 14 (at least temporarily) is referred to as the “valsalva” maneuver accomplished by forcibly blowing air into the middle ear 14 while holding the nose, often called popping the ear. This method is also good for opening the Eustachian tube 26 but it does not clear the accumulated fluid away either.
Typical disorders associated with the middle ear and the Eustachian tube include perforated ear drums, tympanosclerosis, incus erosion, otitis media, cholesteotoma, mastoiditis, patulous Eustachian tube, and conductive hearing loss. To treat some of these disorders, ear surgery may be performed. Most ear surgery is microsurgery, performed with an operating microscope. Types of ear surgery include stapedectomy, tympanoplasty, myringotomy and ear tube surgery.
One of the simplest ear surgeries is the myringotomy or the incision of the ear drum. However, ear surgery can also require the removal of the tympanic membrane for the visualization of the middle ear space. Often surgeons will try to preserve the integrity of the membrane by making incisions in the skin of the ear canal and removing the tympanic membrane as a complete unit. Alternatively, middle ear access is achieved via the mastoids. This method approaches the middle ear space from behind the ears and drills through the mastoid air cells to the middle ear. Whether the bony partition between the external ear canal and the mastoid is removed or not depends on the extent of the disease. Canal-wall-down refers to the removal of this bony partition. Canal-wall-up refers to keeping this bony partition intact. The term modified radical mastoidectomy refers to an operation where this bony partition is removed and the eardrum and ossicles are reconstructed. A radical mastoidectomy is an operation where this bony partition is removed and the ear drum, malleus and incus bones are permanently removed so that the inner lining of the large cholesteatoma sac can be safely cleaned. This operation is done when an extensive cholesteatoma is encountered or one that is adherent to the inner ear or facial nerve.
Afflictions of the middle ear and Eustachian tubes are very prevalent and a serious medical problem, afflicting millions of people and causing pain, discomfort and even hearing loss or permanent ear damage. Although a number of treatments have been developed, as described above each of them has shortcomings. Therefore, a need exists for improved methods and systems for accessing, diagnosing and treating target tissue regions within the middle ear and the Eustachian tube. Ideally, such methods and systems would be minimally invasive and pose very little risk of damage to healthy ear tissue.
BRIEF SUMMARY OF THE INVENTIONThe embodiments of the present invention are directed toward methods and systems for accessing, diagnosing and/or treating target tissue regions within the middle ear and the Eustachian tube. The healthy Eustachian tube opens naturally when adjacent muscles contract to vent the middle ear and provide a gas pathway. Devices may be implanted within or along the Eustachian tube to help intermittently open the Eustachian tube. One type of device utilizes a valve tethered or otherwise operatively coupled to muscles adjacent to the Eustachian tube, and particularly to muscles responsible for opening the Eustachian tube. Such devices may ameliorate disorders which prevent the Eustachian tube from opening, including those caused by thickening of mucosal wall tissue or the like. In some embodiments, when the muscles contract the tethers will move and cause the valve to open and vent the middle ear. Another type of device utilizes compressive tethers on a portion of the mucosa and adjacent cartilage, to compress and shrink the mucosa and help the Eustachian tube open. Another device comprises an elongated spring, which can be implanted within or along the Eustachian tube to aid in opening of the Eustachian tube.
In one embodiment of the invention, a method for providing a gas pathway in the middle ear region of a patient is provided. A guide wire is advanced into the Eustachian tube (ET) of the patient via the patient's nasopharynx. An endoluminal ET ventilating implant is introduced via the patient's nasopharynx along the guide wire into the Eustachian tube of the patient. The implant is advanced into the ET adjacent the cartilage and tensor villi palatine or the levator villi palatine muscles. The implant is dimensioned for insertion into the ET adjacent the nasopharynx. The implant is tethered to the ET cartilage using a first connector. The implant is tethered to the tensor villi palatine or the levator villi palatine muscles using a second connector. A gas pathway is provided between the ET lumen and the nasopharynx using the implant, the implant being dimensioned and configured to modulate an opening in a gas pathway in communication with the ET lumen and the nasopharynx.
In many embodiments, the implant comprises a tube located in the ET lumen. In many embodiments, the implant further comprises a valve in fluid communication with the lumen, the valve having a first valve portion and a second valve portion, the first valve portion being connected with said first connector, and said second valve portion being connected with said second connector. The valve can be configured to modulate the opening during swallowing due to movement of the tensor villi palatine or the levator villi palatine muscles.
In many embodiments, the guide wire includes at least one marking and the method further comprises viewing a location of the marking relative to anatomy of the patient during the advancing method to determine how far to advance the guide wire into the ET.
In another embodiment of the invention, an endoluminal implant for providing a gas pathway between the nasopharynx and the Eustachian tube (ET) is provided. The implant comprises a lumen dimensioned for insertion into the ET at an end adjacent the nasopharynx, through the patient's nasopharynx. A valve is in fluid communication with the lumen. The valve has a first valve portion and a second valve portion. A first connector portion is connected with the first valve portion to tether the implant to the cartilage adjacent the ET. A second connector portion is connected with the second valve portion to tether the implant to the adjacent tensor villi palatine or the levator villi palatine muscles.
In many embodiments, the first connector portion comprises a first tether configured to span across the cartilage and compress the mucosa of the ET lumen to secure the first valve portion with the cartilage. The proximal end of said first connector portion can have a T-shaped member to secure against the cartilage.
In many embodiments, the valve is configured to modulate opening of the ET during swallowing. The valve can be configured to modulate opening of the ET in response to the movement of the tensor muscles.
In yet another embodiment of the invention, another method for providing a gas pathway in the middle ear region of a patient is provided. An endoluminal ET ventilating implant is introduced via the patient's nasopharynx into a Eustachian tube (ET) of a patient. A gas pathway is provided between the ET lumen and the nasopharynx using the implant. The implant is dimensioned and configured to modulate an opening in a gas pathway in communication with the ET lumen and the nasopharynx. In many embodiments, the implant comprises an elongated spring member which applies a constant force against the ET.
In yet another embodiment of the invention, another endoluminal implant for providing a gas pathway between the nasopharynx and the Eustachian tube (ET) is provided. The implant comprises an elongated spring member dimensioned for insertion into the ET at an end adjacent the nasopharynx, through the patient's nasopharynx. The elongated spring member applies a force to modulate an opening in a gas pathway in communication with the ET lumen and the nasopharynx. In many embodiments, the implant is configured to cause tissue ingrowth.
In yet another embodiment of the invention, another method for providing a gas pathway in the middle ear region of a patient is provided. An implant is introduced via the patient's nasopharynx into a Eustachian tube (ET) of a patient. The implant is coupled to adjacent cartilage to compress a wall of the ET. A gas pathway is provided between the ET lumen and the nasopharynx using the tethering implant.
In yet another embodiment of the invention, another endoluminal implant for providing a gas pathway between the nasopharynx and the Eustachian tube (ET) is provided. The implant comprises a first connector portion, and a member with a first end and a second end. The first end is connected to the first connector portion. A second connector portion is configured to attach to the second end of the member. The member is of a suitable length, so that the member compresses a portion of the ET wall between the first and second ends.
For a further understanding of the nature and advantages of the invention, reference should be made to the following description taken in conjunction with the accompanying figures. Each of the figures is provided for the purpose of illustration and description only and is not intended to limit the scope of the embodiments of the present invention.
The embodiments of the present invention are directed toward methods and systems for accessing, diagnosing and treating target tissue regions within the middle ear and the Eustachian tube.
Access
One embodiment of the present invention is directed toward using minimally invasive techniques to gain trans-Eustachian tube access to the middle ear. A middle ear space may be accessed via a Eustachian tube (ET). To obtain this access to the Eustachian tube orifice, a guide catheter having a bend on its distal tip greater than about 30 degrees and less than about 90 degrees may be used. Once accessed, diagnostic or interventional devices may be introduced into the Eustachian tube. Optionally, to prevent damage to the delicate middle ear structures, a safety mechanism may be employed. In one embodiment, the safety mechanism may include a probe and/or a sensor introduced into the middle ear via the tympanic membrane as shown in
Diagnosis
Another embodiment of the present invention is directed to diagnosis of the condition of the middle ear and its structure. In one embodiment, diagnosis may include use of an endoscope that has been advanced into position through the guide catheter 100. The design of the endoscope will allow for a 90 degree or more Y axis visualization and a 360 degree rotation. Such an endoscope may be used for assessment of cholesteotomas, ossicle function and/or condition, and the surgical follow-up. An exemplary endoscope that may be adapted as described above may use the IntroSpicio 115 1.8 mm camera developed by Medigus. Such a camera measures approximately 1.8 mm×1.8 mm and its small rigid portion allows for the maximum flexibility at the endoscope tip.
Alternatively, ultrasound may be used by injecting a fluid into the middle ear space and the ET and scanning the middle ear and the ET and its structure ultrasonically. Post-procedure the fluid may be aspirated or left to drain through the Eustachian tube. An ultrasound tipped catheter may be advanced up the ET to a position at the middle ear cavity. The ultrasound catheter may then be pulled down the ET and the physician may use an external video monitor to view the structure in and adjacent the ET.
Functional diagnosis of the Eustachian tube may be achieved via direct or indirect assessment. In one embodiment, for direct assessment, the diagnostic system may allow for the dynamic monitoring of the Eustachian tube during swallowing via a diagnostic probe inserted via the nasopharynx. Since such a diagnostic system may be used dynamically during swallowing, the probe may be made of a flexible and durable material configured to be atraumatic. In one embodiment, the guide catheter(s) 100 used in the nasopharynx approach may be removed once the diagnostic probe is in or near the ET region and prior to the swallowing.
In one embodiment, the diagnostic probe may comprise an endoscope to visualize the ET structure and function. Alternatively, the diagnostic probe may include a pressure transducer located on a catheter or a wire. When a pressure transducer is used, the pressure within the ET may be monitored during swallowing and the pressure measurements may be interpreted for ET opening function. Alternatively, an ultrasound probe may be inserted in the ET lumen to scan the ET region's structure. Fluid may be introduced into the ET to facilitate ultrasound diagnosis. For any of the above diagnostic systems, a single short length transducer that is repositioned after each swallow may be used. Alternatively, an array of transducers may be used to facilitate mapping of all or a portion of an ET.
The techniques described above may be used to directly access and diagnose a Eustachian tube of a patient. In one embodiment, a method for accessing a Eustachian tube of a patient may include inserting a guide catheter into a nasal passage of the patient, the guide catheter having a distal tip with a bend having an angle between about 30 and about 90 degrees; and advancing the guide catheter in the nasal passage toward an opening of the Eustachian tube in the nasopharynx to place the distal tip adjacent the Eustachian tube opening. Additionally, the method may also include advancing a diagnostic device through the guide catheter to place a distal tip of the diagnostic device adjacent the Eustachian tube opening. The diagnostic device may include a diagnostic catheter. The diagnostic device may include an endoscope, a pressure transducer, or an ultrasound catheter.
Additionally, the method may also include introducing a diagnostic probe into the Eustachian tube to directly assess Eustachian tube function. It is preferred that the diagnostic probe is made from a flexible and Eustachian tube compatible material. Alternatively, the diagnostic probe may comprise a pressure transducer located on a guide wire, and whereby the method also includes monitoring pressure within the Eustachian tube while the patient is swallowing; and assessing an opening function of the patient's Eustachian tube using the monitoring. The method may also include removing the guide catheter after the diagnostic probe is placed into the Eustachian tube. Additionally, or alternatively, the diagnostic probe may comprise an ultrasound probe.
For indirect functional diagnosis of a Eustachian tube, in some embodiments, an external energy source may be used to assess opening of the Eustachian tube. For example, possible energy sources may include, but are not limited to, pressure, sound, light or other electromagnetic energy. In one embodiment of indirect assessment, an emitter may be positioned in the nasopharynx and a receiver may be placed at the tympanic membrane. Correlation between the emitted signal and the received signal may be translated into the physical characteristics of the ET during swallowing.
The techniques described above may be used to implement procedures for indirectly accessing and diagnosing the Eustachian tube of a patient. The indirect assessment method includes positioning an energy emitter in the nasopharynx adjacent a Eustachian tube, positioning an energy receiver adjacent the tympanic membrane via the external ear canal; directing energy from the emitter toward the receiver; generating an emitter signal representative of the energy from the emitter; generating a receiver signal representative of the energy received by the emitter; forming a comparison between the emitter signal and the receiver signal; and indirectly assessing function of the Eustachian tube during swallowing, using the comparison. The energy emitter can be a device that emits energy in the form of a pressure wave or electromagnetic energy. The indirect assessment may also include estimating the physical characteristics of Eustachian tube.
Treatment
An embodiment of the present invention is directed toward the treatment of Eustachian tube disorders. In some cases, for example, Eustachian tube disorders may be related to the Eustachian tube being unable to open or close. In some cases mucosal tissue of the Eustachian tube may thicken, such that the adjacent muscles become ineffective in opening the Eustachian tube in order to provide a gas pathway between the Eustachian tube and the nasopharynx.
The valve 904 is shown to include a first valve portion 906 and a second valve portion 908. The valve 904 is normally in a closed configuration when implanted, with the first and second valve portions sealingly engaging each other, as the Eustachian tube is also normally closed. The first and second valve portions are configured to open and close with physiological movement of tissues near the Eustachian tube, typically with movement of the tensor villi palatine or the levator villi palatine muscles (depending on which ear the device 900 is placed in), for example, during swallowing. The first and second valve portions can include tethers 910 or other tension members. The members or tethers can (but need not) comprise laterally flexible tension members. One side of the tethers 910A can be connected to the tensor villi palatine or the levator villi palatine muscles. Another side of the tethers 910B can be connected to cartilage adjacent to the Eustachian tube. Accordingly, movement of the tensor villi palatine or the levator villi palatine muscles will cause the tethers 910A to move and in turn cause the second valve portion 908 to separate from the first valve portion 906, and cause the Eustachian tube to open.
The tethers 910A are intended to be able to move with the tensor villi palatine or the levator villi palatine muscles, and are configured to pass through the Eustachian tube wall. The tethers 910A may incorporate outer sleeves (not shown) for tissue to adhere to, but still allow movement of the tethers 910. The tethers 910B are intended to pass through the Eustachian tube wall and connect to adjacent cartilage. The tethers 910B are not required to move. The tethers 910B can be of appropriate length to compress surrounding mucosa and thus reduce the effective inner diameter of the Eustachian tube. The tethers 910 are connected to the appropriate muscles or cartilage through anchoring members 912 which anchor to tissue. The valve 903 is shown to occupy a portion of the lumen 902, however, in some embodiments the valve may occupy the entirety of the lumen when in the closed configuration. In some embodiments, a plurality of valves 904 may occupy the lumen 902.
As shown, the anchoring member 912 includes a first portion 84 which at one end defines a cylindrical structure and at the other a partial cylindrical structure. When unconstrained, this first portion 84 forms a T-bar or top of the anchoring member 82. A complementary partial cylindrical structure forms a mid-section or second portion 86 of the anchoring member 82 and operates as a spring to accomplish the flipping of the first portion 84 between constrained and unconstrained configurations. When the component is in its constrained, straight form, the second portion is positioned adjacent the first portion 84. A third portion 88 is also cylindrical in shape and extends from the second portion 86 away from the first portion 84. The third portion 88 can attach to one end of a tether 910. Another anchoring member can attach to the other end of the tether. One commonly skilled in the art would recognize that other types of anchoring devices may be used or adapted, and devices for implanting such anchoring devices, for example, as shown and described in U.S. patent application Ser. No. 11/492,690, Publication No. 2007/0049929A1, the entirety of which is incorporated herein in its entirety.
The present invention may be embodied in other specific forms without departing from the essential characteristics thereof. For example, devices and methods for accessing the Eustachian tube as disclosed in co-assigned U.S. patent application Ser. No. 12/340,226, the entirety of which is incorporated by reference herein, may be used in conjunction with the instant disclosure. These other embodiments are intended to be included within the scope of the present invention, which is set forth in the following claims.
Claims
1-16. (canceled)
17. A method of providing a gas pathway between a Eustachian tube (ET) and a nasopharynx of a patient, comprising:
- (a) providing an endoluminal implant within the ET such that a first body portion of the endoluminal implant is secured relative to a posterior wall of the ET and a second body portion of the endoluminal implant is secured relative to an anterior wall of the ET;
- (b) assuming a closed position with the endoluminal implant in which the first body portion confronts the second body portion to thereby inhibit passage of gas through an implant lumen of the endoluminal implant; and
- (c) in response to movement of tissue in the region of the ET, transitioning to an open position with the endoluminal implant in which the first and second body portions are spaced apart from one another to thereby permit passage of gas through the implant lumen and between the ET and the nasopharynx.
18. The method of claim 17, wherein the first body portion is anchored to at least one of the tensor villi palatine muscle or the levator villi palatine muscle with a first coupling feature, wherein the second body portion is anchored to cartilage in the region of the ET with a second coupling feature.
19. The method of claim 18, wherein the first coupling feature extends through the posterior wall of the ET, wherein the second coupling feature extends through the anterior wall of the ET.
20. The method of claim 18, wherein the first coupling feature includes a first tether, wherein the second coupling feature includes a second tether.
21. The method of claim 18, wherein at least one of the first coupling feature or the second coupling feature includes a plurality of tethers.
22. The method of claim 17, wherein the endoluminal implant includes a valve, wherein assuming the closed position with the endoluminal implant includes assuming a closed position with the valve, wherein transitioning to the open position with the endoluminal implant includes assuming an open position with the valve.
23. The method of claim 22, wherein the first body portion includes a first valve portion of the valve, wherein the second body portion includes a second valve portion of the valve.
24. The method of claim 23, wherein the first and second valve portions sealingly engage one another in the closed position.
25. The method of claim 22, wherein the valve is arranged within the implant lumen.
26. The method of claim 17, further comprising exerting an outwardly directed force on the ET with the endoluminal implant to thereby bias the ET toward an open state.
27. The method of claim 26, wherein exerting an outwardly directed force on the ET with the endoluminal implant includes exerting a resilient bias force on the posterior wall of the ET with the first body portion and simultaneously exerting a resilient bias force on the anterior wall of the ET with the second body portion.
28. The method of claim 27, wherein the first and second body portions are resiliently biased relative to one another.
29. The method of claim 28, wherein the first and second body portions are coupled together in an elongate clamshell configuration.
30. The method of claim 17, wherein the first body portion is positioned within or behind the posterior wall of the ET, wherein the second body portion is positioned within or behind the anterior wall of the ET.
31. The method of claim 17, further comprising eluting a therapeutic substance from the endoluminal implant.
32. A method of providing a gas pathway between a Eustachian tube (ET) and a nasopharynx of a patient, comprising:
- (a) providing an endoluminal implant within the ET, wherein the endoluminal implant includes an implant lumen and a valve arranged within the implant lumen;
- (b) assuming a closed position with the valve to inhibit passage of gas through the implant lumen; and
- (c) in response to movement of tissue in the region of the ET, transitioning to an open position with the valve to thereby permit passage of gas through the implant lumen and between the ET and the nasopharynx.
33. The method of claim 32, wherein a first valve portion of the valve is anchored relative to a first side of the ET, wherein a second valve portion of the valve is anchored relative to a second side of the ET.
34. The method of claim 33, wherein assuming the closed position with the valve includes sealingly engaging the first valve portion with the second valve portion, wherein assuming the open position with the valve includes disengaging the first valve portion from the second valve portion.
35. A method of providing a gas pathway between a Eustachian tube (ET) and a nasopharynx of a patient, comprising:
- (a) providing an endoluminal implant within the ET such that a first body portion of the endoluminal implant is positioned within or behind a posterior wall of the ET and a second body portion of the endoluminal implant is positioned within or behind an anterior wall of the ET; and
- (b) exerting a resilient bias force on the posterior wall with the first body portion and simultaneously exerting a resilient bias force on the anterior wall with the second body portion to thereby urge the ET toward an open state to permit passage of gas between the ET and the nasopharynx.
36. The method of claim 35, wherein the first and second body portions are resiliently biased away from one another.
Type: Application
Filed: Jul 2, 2019
Publication Date: Dec 26, 2019
Inventors: Anton G. Clifford (Mountain View, CA), Joshua Makower (Los Altos, CA), John Y. Chang (Los Altos, CA), John H. Morriss (Emerald Hills, CA), Earl A. Bright, II (Los Altos, CA), Eric Goldfarb (Belmont, CA), Julia D. Vrany (Los Altos, CA), Ketan P. Muni (San Jose, CA), William E. Bolger (Bethesda, MD), Joseph Roberson (Palo Alto, CA)
Application Number: 16/459,690