U.S. patent application number 12/702589 was filed with the patent office on 2010-06-10 for method and device for treatment of obstructive sleep apnea.
Invention is credited to Douglas C. Harrington.
Application Number | 20100139668 12/702589 |
Document ID | / |
Family ID | 40220492 |
Filed Date | 2010-06-10 |
United States Patent
Application |
20100139668 |
Kind Code |
A1 |
Harrington; Douglas C. |
June 10, 2010 |
Method and Device For Treatment Of Obstructive Sleep Apnea
Abstract
This invention relates to devices and methods for maintaining
upper airway patency during sleep for the treatment of sleeping
disorders, upper airway resistance syndrome, snoring and
obstructive sleep apnea.
Inventors: |
Harrington; Douglas C.; (San
Jose, CA) |
Correspondence
Address: |
CROCKETT & CROCKETT, P.C.
26020 ACERO, SUITE 200
MISSION VIEJO
CA
92691
US
|
Family ID: |
40220492 |
Appl. No.: |
12/702589 |
Filed: |
February 9, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11772910 |
Jul 3, 2007 |
7658192 |
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12702589 |
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Current U.S.
Class: |
128/848 |
Current CPC
Class: |
A61F 2/00 20130101; A61F
5/56 20130101 |
Class at
Publication: |
128/848 |
International
Class: |
A61F 5/44 20060101
A61F005/44 |
Claims
1. A method for maintaining a patient's tongue to prevent sleep
related breathing disorders comprising the steps of: forming a
lateral channel at the base of the patient's tongue; positioning a
restrainer, said restrainer being conformable into the tongue, and
said restrainer being sized and dimensioned to fit into the lateral
channel wherein the restrainer is capable of suspending the tongue
away from the patient's throat during sleep; and securing the
restrainer to the interior surface of the patient's mandible to
suspend the tongue away from the patient's throat during sleep such
that the restrainer suspends the tongue from the patient's throat
while the patient is in the supine position but the restrainer does
not suspend the tongue while the patient is upright.
2. The method of claim 1, wherein the securing step comprises
securing the restrainer to the medial interior surface of the
patient's mandible to suspend the tongue away from the patient's
throat during sleep.
3. The method of claim 1, wherein the securing step comprises
securing the restrainer to the interior surface of the patient's
mandible to suspend the tongue away from the patient's throat
during sleep such that the entire width of the tongue is suspended
away from the patient's throat during sleep.
4. The method of claim 2 wherein the securing step further
comprises securing the implant to the medial surface of the
mandible around the chin so that both ends of the restrainer are
attached at the same point.
5. The method of claim 1, wherein the step of forming the lateral
channel is performed through the patient's mouth.
6. The method of claim 1, wherein the step of forming the lateral
channel is performed from below the chin.
7. The method of claim 1, wherein only a portion of the restrainer
comprises an elastic material.
8. The method of claim 1, wherein the entire method is completed in
a single procedure.
9. The method of claim 1, wherein the steps of forming a lateral
channel and positioning the restrainer are performed in a single
procedure and the step of securing the restrainer is performed in a
separate procedure.
10. The method of claim 1, wherein the restrainer is secured with
bone screws.
11. The method of claim 1, wherein the restrainer is secured with
surgical staples.
12. The method of claim 1, wherein the restrainer is secured with
sutures.
Description
[0001] This application is a continuation application of U.S.
application Ser. No. 11/772,910, filed Jul. 3, 2007, now U.S. Pat.
No. 7,658,192.
FIELD OF THE INVENTIONS
[0002] The inventions described below relate the field of methods
and devices for treatment of sleeping disorders, upper airway
resistance syndrome, snoring and obstructive sleep apnea.
BACKGROUND OF THE INVENTIONS
[0003] According to a report published in the April 2004 Journal of
the American Medical Association, it is estimated that one in five
adults, or approximately 44 million people in the United States
suffers from mild obstructive sleep apnea (OSA) and that
approximately 15 million people in the United States suffer from
moderate or more severe OSA. In a separate report, the American
Association of Orthodontists estimates that 55 million people in
the United States suffer from habitual or socially disruptive
snoring.
[0004] Obstructive sleep apnea is caused by the closing of the
upper airway while a person is asleep. The uvula and soft pallet
collapses on the back wall of the upper airway. Then the tongue
falls backward, collapsing on the back wall of the upper airway,
the uvula and soft pallet forming a tight blockage, preventing any
air from entering the lungs. The effort of the diaphragm, the chest
and the abdomen only cause the blockage to seal tighter. In order
to breathe, the person must arouse or awaken. This creates tension
in the tongue thereby opening the airway, allowing air to pass into
the lungs.
[0005] Obstructive sleep apnea causes a drop in a person's blood
oxygen saturation (SaO.sub.2) and an increase in the blood's carbon
dioxide (CO.sub.2). When the SaO.sub.2 drops the heart will start
pumping more blood with each beat. If the SaO.sub.2 continues to
drop the heart will start beating faster and faster. As the
CO.sub.2 increases the brain will try to drive the person to
breathe. The effort and action of the abdomen and chest will
increase. Eventually that action will clear the upper airway
blockage, allowing the person to breathe. A cyclic process of
arousal and falling back to sleep will typically occur throughout
the person's sleep.
[0006] The American Academy of Sleep Medicine rates the average
number of OSA events per hour as your Respiratory Distress Index
(RDI). An RDI of 0 to 5 is normal; 5 to 20 is mild; 20 to 40 is
moderate; over 40 is considered severe. An apnea event must last at
least 10 seconds to be considered an event. It is not uncommon to
see RDIs well above the 40. In some cases RDIs were well above 100,
with events lasting as long as 90 to 120 seconds and SaO.sub.2s
going below 70% when normal is 95% to 100%.
[0007] Obstructive sleep apnea is a serious, potentially
life-threatening condition that is far more common than generally
understood. Recent studies have linked OSA with increased risks of
cardiovascular morbidity, high blood pressure, stroke, heart
attack, Type II diabetes and depression. OSA typically causes
excessive daytime sleepiness, resulting in memory loss, lack of
concentration, slower reaction time that can cause difficulty
driving or operating equipment and sexual dysfunction, such as
impotence and libido.
[0008] There are several methods, devices and surgical procedures
presently available for the treatment of OSA. The most frequently
prescribed and most common treatment is continuous positive airway
pressure, or CPAP. CPAP therapy requires that the patient wear a
nasal or facial mask during sleep that is connected by a tube to a
portable airflow generator, which delivers air at a predetermined
continuous positive pressure. The continuous positive pressure
forces air through the nasal passages and opens the back of the
throat, keeping the upper airway open and unobstructed during
sleep. CPAP prevents upper airway closure while in use, but apnea
or hypopnea episodes return when CPAP is stopped or used
improperly. CPAP is not a cure for OSA, but a lifelong therapy for
managing OSA that must be used on a nightly basis. Noncompliance
rates for CPAP are estimated to exceed 50% due to factors such as
physical discomfort and claustrophobia resulting from use of the
nasal or facial mask, nasal and facial irritation, uncomfortable
sleeping positions, lifestyle changes, social factors and
inconvenience.
[0009] Another mechanical therapy prescribed to treat OSA is a
custom fitted or prefabricated orthodontic like device or oral
appliance that is worn while sleeping. An oral appliance attempts
to reposition the jaw and/or the base of the tongue to prevent the
tongue from collapsing and obstructing the upper airway during
sleep.
[0010] When surgical therapy is indicated, conservative procedures
are attempted first. These procedures include uvulectomy, nasal
reconstruction, Aden tonsillectomy, uvulopalatopharyngoplasty (UPPP
or UP3) and laser assisted uvulopalatoplasty (LAUP). Second line
treatments for OSA are more complex and include genioglossal
advancement with or without hyoid myotomy, maxillary mandibular
advancement, bimaxillary advancement, and tongue base surgery. The
more invasive of these surgical procedures are very painful,
usually require post procedure prescription narcotics to manage
pain, often result in potentially serious post surgical
complications which can involve hospital readmission, usually
result in lengthy recovery periods and are expensive to
administer.
[0011] Uvulopalatopharyngoplasty, currently the most common palatal
surgical treatment for both OSA and snoring, uses a scalpel,
electrocautery, coblation or other cutting technology to remove
excess tissue at the back of the throat (tonsils, uvula, and part
of the soft palate) under general anesthesia. The UPPP procedure is
very painful, often requires an overnight hospital stay, sometimes
requires hospital readmission to resolve complications, and
typically involves lengthy recovery period of up to two weeks.
Surgical success rate is approximately 50% when surgical success is
defined as both 50% reduction in RDI and a postoperative RDI of
less than 20. This is despite preselection of patients where the
uvula and soft palate are identified as the cause of OSA.
[0012] Laser assisted uvulopalatoplasty is similar to UPPP, but
uses heat from a laser to destroy tissue of the soft palate. The
LAUP procedure requires the use of expensive laser capital
equipment and often involves multiple treatments. The clinical and
economic benefits of using LAUP over UPPP have not been well
established and as a result, LAUP procedures are now performed
infrequently.
[0013] A vast majority of people with OSA have tongue base
narrowing or posterior displacement of the tongue into the airway.
Several highly invasive surgical procedures with concomitant high
morbidity but significantly improved clinical results compared to
UPPP and LAUP have been used to address this issue. Genioglossal
(primary muscle of the tongue) advancement involves performing a
mandibular osteotomy (reconstruction of the lower jaw) with
anterior repositioning of the genioglossus attached segment of the
mandible, which results in anterior displacement of the tongue.
This procedure is painful and requires long recovery and sometimes
results in permanent numbness of the lower front teeth.
[0014] Maxillomandibular advancement is the most invasive and
effective surgical treatment for OSA. The procedure involves moving
both the maxilla (upper jaw) and the mandible forward to establish
an open airway. Success rates of 90% to 100% with maxillomandibular
advancement surgery as the primary procedure have been reported.
While speech and swallowing are typically not affected, this
procedure is painful, requires a long recovery and sometimes it
causes numbness of the lower lip and some changes in facial
appearance. Chewing is not allowed for 4 weeks and typically,
patients will not return to work in less than one month post
procedure.
SUMMARY
[0015] The present invention relates to a system and method for
restraining a patient's tongue from falling back into the throat
when sleeping to prevent sleep related breathing disorders. A
portion of the patient's tongue tissue is wounded and a silicone
tongue restrainer is inserted into the tongue tissue and secured to
the patient tissue or bone. The restrainer is sized and dimensioned
to fit within the patient's mouth into the wounded tongue tissue
and the restrainer comprises pores that are sized and dimensioned
to support growth of vascularized tissue within the restrainer and
capable of suspending the tongue away from the patient's throat
during sleep.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a partial sectional view through the head and neck
of an individual;
[0017] FIG. 2 is a view illustrating occlusion of the oropharynx
that occurs during obstructive sleep apnea;
[0018] FIGS. 3a through 3d are views of various configurations of
planar tongue restrainers for use in preventing the tongue from
collapsing;
[0019] FIGS. 4a through 4d are views of various configurations of
cylindrical tongue restrainers for use in preventing the tongue
from collapsing;
[0020] FIG. 5 is a view of the mandible bone with one of the tongue
restrainers in place; and
[0021] FIG. 6 is a view through the head and neck with a tongue
restrainer in place.
DETAILED DESCRIPTION OF THE INVENTIONS
[0022] FIG. 1 illustrates the normal anatomy of the human upper
respiratory system consisting of the nasal cavity 10, pharynx and
larynx 11, 12 which communicates with the trachea 14 (or windpipe).
The nasal cavity is located inside the external nose and joins the
pharynx 11. The floor of the nasal cavity is composed of the hard
palate 16, a bony plate covered by mucosa that separates the oral
cavity 18 from the nasal cavity. Posterior to the hard palate is a
non-bony segment of tissue, the soft palate 20, which consists of
skeletal muscle and connective tissue. The uvula 22 is a soft
process that extends downwardly from the posterior edge of the soft
palate.
[0023] The pharynx is divided into three regions, the nasopharynx
24, the oropharynx 26, and the laryngopharynx 28. The nasopharynx
is the superior portion of the pharynx, which extends from the
nasal cavity to the level of the uvula. The oral cavity opens into
the oropharynx, which extends from the uvula to the epiglottis 30.
The laryngopharynx extends from the tip of the epiglottis to the
openings of the larynx and the esophagus 32.
[0024] The tongue 34 consists of a mass of intrinsic muscles, which
are involved in changing the shape of the tongue, and extrinsic
muscles, which help change the shape and move the tongue. The major
extrinsic muscles include the hyoglossus, styloglossus,
palatoglossus and genioglossus. The genioglussus' primary function
is depression and protrusion of the tongue.
[0025] FIG. 2 is a view illustrating occlusion of the oropharynx 26
that occurs during obstructive sleep apnea. Obstructive sleep apnea
is caused by repetitive airway obstruction during sleep as a result
of narrowing of the respiratory passages. The base of the tongue 34
is the most common site of obstruction in sleep apnea. The
obstruction or collapse of the passageway occurs when the base of
the tongue abuts the posterior wall and soft palate 20. Decreased
airway muscle tone during sleep and the pull of gravity in the
supine position can further decrease airway size, further impeding
airflow during respiration.
[0026] FIGS. 3a through 4d are views of various configurations of
tongue restrainers 36 for use in preventing the tongue from
collapsing into the throat when sleeping. The device shown in the
figures comprises a silicone restrainer that is capable of being
positioned into the base of the tongue or posterior portion of the
tongue of a patient to restrain or prevent the tongue from
collapsing posteriorly or back towards the throat during sleep. The
restrainer can be variously shaped and may be a strip, sheet, rod
or string of material and is sized and dimensioned to fit within a
patient's mouth. The restrainer contains pores that are sized and
dimensioned to support growth of vascularized tongue tissue within
the pores. The restrainer can be secured into the tongue muscle or
placed just below the mucosal tissues.
[0027] The restrainer can be attached to adjacent tissues or bones
to assist supporting the tongue base or alternatively implanted
into the tongue base without further attachment. Attachment of the
restrainer to tissues and bone can be accomplished in various ways
including use of bone screws, surgical staples, sutures or any
other suitable means for anchoring the restrainer in place.
[0028] FIGS. 3a through 3d illustrate various planar restrainer
configurations. FIG. 3a is a view of a planar restrainer 36 made of
silicone. The restrainer can be a sheet that is either solid or
porous throughout. FIG. 3b is a view of a planar restrainer
consisting of a sheet of silicone with a solid portion 38
sandwiched in between two porous sections 40. FIG. 3c is a view of
a planar restrainer consisting of individual sections, two outer
sections 42 and an inner section 44. The two outer sections can be
made of a different silicone than the inner section allowing for
variations of hardness and porosity along the restrainer. FIG. 3d
is a view of a planar restrainer that is a combination of the
restrainer of FIGS. 3b and 3c. This configuration is a planar sheet
of silicone with solid sections of silicone 38 sandwiched in
between two outer porous sections 40 located at both ends.
Alternatively, the restrainer can be a porous sheet with
reinforcing materials such as fibers and meshes located at the
ends. The pores contained on the restrainer are sized and
dimensioned to support growth of vascularized tongue tissue within
the restrainer. The planar restrainers are approximately 2 to 16
centimeters in length, 2 to 30 millimeters in width and 0.5 to 5
millimeters in thickness. One example of a planar restrainer
configuration would be approximately 10 centimeters in length, 1
centimeter in width and 2 millimeters in thickness.
[0029] FIGS. 4a through 4d illustrate various cylindrical
restrainer configurations. FIG. 4a is a view of a cylindrical
restrainer made of silicone. The restrainer can be either solid or
porous throughout. FIG. 4b is a view of a cylindrical restrainer
consisting of a solid center section 46 throughout the length of
the cylinder. The solid section may also contain reinforcing
materials such as filaments and fibers. FIG. 4c is a view of a
cylindrical restrainer consisting of two solid center end sections
50 to allow for variable properties along the cylindrical
restrainer. FIG. 4d is a view of a cylindrical restrainer with a
solid central section 52 allowing for variable properties along the
cylindrical restrainer. The cylindrical restrainers are
approximately 2 to 16 centimeters in length, 1 to 10 millimeters in
diameter. One example of a cylindrical restrainer configuration
would be approximately 10 centimeters in length and 3 millimeters
in diameter.
[0030] The restrainers 36 can be made of various types of silicones
possessing different properties. For example, the material could be
elastic in nature so that during mastication (chewing and
swallowing) the tongue is allowed to move posteriorly and in
natural motions. In this way, the restrainer would only create
enough muscle resistance or support to restrain or prevent the
tongue from falling back into the larynx during muscle relaxation
that occurs during deep sleep. The restrainer is not used to pull
the tongue forward, only to restrain or prevent the tongue from
falling back into the throat when sleeping, particularly when lying
on your back. This elastic characteristic could also prevent
erosion or extrusion of the restrainer during repetitive motion
that would most likely occur if only simple non-compliant,
inelastic surgical suture was employed for this application.
Suitable materials with these characteristics include silicone
polymers, natural rubbers, thermoplastic elastomers such as
thermoplastic polyurethane (Pellethane.TM., Tecoflex.TM.,
Tecothane.TM. Versaflex.TM.), polyetheramide (Pebax.TM.), styrene
block copolymers (Kraton.TM., Dynaflex.TM.), thermoplastic
vulcanizate (Versaflex.TM.) and others. The porous sections of the
restrainer can be reticulated, meaning that the pores communicate
with other pores, rather than existing as discrete and isolated
voids within the material.
[0031] The restrainer may also be fabricated from expanded
Polytetrafluoroethylene, commonly referred to as ePTFE. The
restrainer could also just be covered with ePTFE or placed only on
specific sections of the restrainer. One method of manufacturing
ePTFE starts with a PTFE rod or sheet, the rod is stretched to
expand the PTFE to form the system of nodes and fibrils
characteristic of ePTFE.
[0032] Where nonporous sections are incorporated into the
restrainer, the sections can either be solid material with or
without reinforcing members such as polyester or polyethylene or
propylene or Kevlar fibers, threads and/or meshes. Incorporation of
reinforcing components at the ends of the restrainer assists in
attachment to tissues such as the mandible bone by a bone screw and
prevents the restrainer from tearing once in place. Placement of
reinforcement in the middle and other sections controls the amount
of stretch or elasticity desired within the restrainer.
[0033] In use, the restrainer can be implanted into the tongue
tissues by various methods. To place a restrainer, a surgeon forms
a lateral channel at the base of a patient's tongue. The surgeon
then places a strap into the lateral channel and secures the ends
of the strap to the interior surface of the mandible. The surgeon
can also form the lateral channel at the same time that he places
the strap into the channel by using a needle passer that pulls the
strap implant through the tissue as it simultaneously tunnels
through the tissue. This method is similar to the various
techniques employed for placement of devices used for the treatment
of female urinary stress incontinence. Alternatively, the surgeon
can perform tissue incision and dissection with a scalpel or
electrosurgical devices. The surgeon can dissect the tissue from a
superior approach and tissue pockets or chambers can be created
within the tissue. The surgeon may also pre-treat the patient
tissue with an energy source such as thermal energy, radiofrequency
energy, cryogenic energy and the like to stimulate an inflammatory
response to assist with tissue ingrowth into the restrainer.
[0034] FIG. 5 is a view of the mandible bone with one of the tongue
restrainers 36 in place. The restrainer is positioned into a
channel within the patient's mouth. The restrainer is capable of
being positioned into the base of the tongue or posterior portion
of the tongue of the patient to prevent the tongue from collapsing
posteriorly while the patient is sleeping.
[0035] FIG. 6 is a view through the head and neck with a tongue
restrainer in place. The restrainer is positioned within the
lateral channel formed by the surgeon and secured to the inner
surface of the mandible. The restrainer is positioned between the
nasopharynx 24 and the laryngopharynx 28 within the channel so that
the restrainer prevents occlusion of the oropharynx 26.
[0036] Placement of a restrainer having suitable flexibility,
architecture and pore size into the excised tissue encourages
healing tissue to grow into the restrainer. Ingrowth of healthy
vascularized tissue into the restrainer prevents or discourages
formation of scar tissue around the restrainer and minimizes the
potential for restrainer migration and extrusion. Where the pore
size is large relative to the cell size, in the range of 40-200
microns, and of a specific architecture, the body will heal by
forming a vascularized tissue within the pores of the restrainer. A
porous restrainer in its final form will comprise numerous
filaments of the foam superstructure, which form a network of
communicating pores, with vascular tissue occupying the pores.
Large pore size materials can be manufactured in various ways
including sintering and molding. For example, porous silicone can
be made by injecting polydimethylsiloxane into a form packed with
granules. The silicone is cured and the particles are dissolved in
a suitable solvent (water, where sugar or salt is used) to form the
porous restrainer with communicating pores. Pore size is determined
by the size of the dissolved particles. The porous silicone implant
can have a durometer value between 20-100 Shore A.
[0037] The restrainer can be implanted during one surgical
procedure and affixed to the anchor points (e.g. bone) during a
second procedure. This would allow tissue to sufficiently grow into
the implant before fixation of the implant. A second procedure may
be performed from several days to months from the first.
[0038] While the preferred embodiments of the devices and methods
have been described in reference to the environment in which they
were developed, they are merely illustrative of the principles of
the inventions. Other embodiments and configurations may be devised
without departing from the spirit of the inventions and the scope
of the appended claims.
* * * * *