U.S. patent application number 14/305102 was filed with the patent office on 2015-03-12 for devices, systems, and methods to fixate tissue within the regions of body, such as the pharyngeal conduit.
The applicant listed for this patent is KONINKLIJKE PHILIPS N.V.. Invention is credited to Ryan P. BOUCHER, Eric N. DOELLING, Ronald G. LAX, Jinfang LIU, Lionel M. NELSON, Allan R. WILL.
Application Number | 20150073565 14/305102 |
Document ID | / |
Family ID | 34633214 |
Filed Date | 2015-03-12 |
United States Patent
Application |
20150073565 |
Kind Code |
A1 |
NELSON; Lionel M. ; et
al. |
March 12, 2015 |
DEVICES, SYSTEMS, AND METHODS TO FIXATE TISSUE WITHIN THE REGIONS
OF BODY, SUCH AS THE PHARYNGEAL CONDUIT
Abstract
Devices, systems and methods develop static and/or kinetic
and/or pressure forces to fixate or brace tissue in targeted
pharyngeal structures and individual anatomic components within the
pharyngeal conduit.
Inventors: |
NELSON; Lionel M.; (LOS
ALTOS, CA) ; DOELLING; Eric N.; (SUNNYVALE, CA)
; LAX; Ronald G.; (TARPON SPRINGS, FL) ; LIU;
Jinfang; (LANCASTER, PA) ; BOUCHER; Ryan P.;
(SAN FRANCISCO, CA) ; WILL; Allan R.; (ATHERTON,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KONINKLIJKE PHILIPS N.V. |
EINDHOVEN |
|
NL |
|
|
Family ID: |
34633214 |
Appl. No.: |
14/305102 |
Filed: |
June 16, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12148175 |
Apr 17, 2008 |
8752552 |
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14305102 |
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|
10718254 |
Nov 20, 2003 |
7360542 |
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12148175 |
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10656861 |
Sep 6, 2003 |
7188627 |
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10718254 |
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10236455 |
Sep 6, 2002 |
7216648 |
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10656861 |
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Current U.S.
Class: |
623/23.72 |
Current CPC
Class: |
A61F 2/04 20130101; A61F
2/00 20130101; A61F 5/56 20130101; A61F 2250/006 20130101 |
Class at
Publication: |
623/23.72 |
International
Class: |
A61F 2/04 20060101
A61F002/04; A61F 5/56 20060101 A61F005/56 |
Claims
1. An arrangement adapted to resist collapse of a portion of a
pharyngeal wall, the arrangement comprising: a plurality of
individual implants, each of the implants being sized and
configured for implantation in the portion of the pharyngeal wall
and once implanted, are sized and configured to be movable among: a
first arrangement in which the plurality of individual implants are
spaced a predetermined distance apart along an arc defined by a
radius, and a second arrangement in which one or both of the
distance or radius has decreased.
2. The arrangement of claim 1 wherein when disposed in the second
arrangement, one or more of the individual implants are disposed in
direct contact with another one or more of the individual
implants.
3. The arrangement of claim 1 wherein each of the individual
implants are linked together by a material.
4. The arrangement of claim 3 wherein the material comprises one or
more selected from the group consisting of: a plastic, a metal, a
fabric, a textile, and a ceramic.
5. The arrangement of claim 3 wherein the material is of a
negligible stiffness.
6. The arrangement of claim 3 wherein the material is of a
stiffness sufficient to impart a flexural resistance upon adjacent
implants linked thereby.
7. An implant sized and configured for implantation in a portion of
a pharyngeal wall and adapted to resist collapse of the portion of
the pharyngeal wall, the implant comprising: a body comprising a
plurality of segments, each segment being coupled to an adjacent
segment via a hinge point, wherein the body is flexible from among:
a first arrangement in which each of the hinge points are disposed
on an open position, and a second arrangement in which one or more
of the hinge points are disposed in a closed position such that the
one or more hinge points disposed in the closed position resist
further flex of the body such hinge points.
8. The implant of claim 7 wherein the body comprises one or more of
a plastic, metal, fabric, or ceramic material.
9. The implant of claim 7 wherein each hinge point is adapted to
delimit a spacing and a closure angle of the segments connected
thereby.
10. The implant of claim 9 wherein the spacing delimited by one
hinge point differs from the spacing delimited by another hinge
point.
11. The implant of claim 7 wherein closure angle delimited by one
hinge point differs from the closure angle delimited by another
hinge point.
12. The implant of claim 7 wherein each of the segments is formed
from a generally inelastic material.
13. The implant of claim 7 wherein each of the segments is formed
as a spring-like structure.
14. A method of bracing a portion of a pharyngeal wall, the method
comprising: surgically implanting a plurality of individual
implants at predetermined spacings along an arc-shaped arrangement
in the pharyngeal wall.
15. A method of bracing a portion of a pharyngeal wall, the method
comprising implanting the implant of claim 7 in a portion of a
pharyngeal wall.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No.
12/148,175, filed Apr. 17, 2008 which was co-pending at the time of
filing and subsequently issued as U.S. Pat. No. 8,752,552; which is
a divisional of application Ser. No. 10/718,254 filed Nov. 20, 2003
and issued as U.S. Pat. No. 7,360,542; which is a
continuation-in-part of U.S. patent application Ser. No.
10/656,861, filed Sep. 6, 2003 entitled "Magnetic Force Devices,
Systems, and Methods for Resisting Tissue Collapse within the
Pharyngeal Conduit", and issued as U.S. Pat. No. 7,188,627; which
claims the benefit of U.S. Provisional Patent Application Ser. No.
60/441,639, filed Jan. 22, 2003 and entitled "Magnetic Splint
Device and Method for the Treatment of Upper Airway Collapse in
Obstructive Sleep Apnea, and the benefit of U.S. Provisional Patent
Application Ser. No. 60/456,164, filed Mar. 20, 2003 and entitled
"Device and Method for Treatment of Sleep Related Breathing
Disorders Including Snoring and Sleep Apnea". The application Ser.
No. 10/718,254 is also a continuation-in-part of U.S. patent
application Ser. No. 10/236,455, filed Sep. 6, 2002 and entitled
"Systems and Methods for Moving and/or Restraining Tissue in the
Upper Respiratory System", and issued as U.S. Pat. No. 7,216,648.
Each of the aforementioned applications are incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The invention is directed to devices, systems, and methods
for the treatment of sleep disordered breathing including
obstructive sleep apnea.
BACKGROUND OF THE INVENTION
I. The Characteristics of Sleep Apnea
[0003] First described in 1965, sleep apnea is a breathing disorder
characterized by brief interruptions (10 seconds or more) of
breathing during sleep. Sleep apnea is a common but serious,
potentially life-threatening condition, affecting as many as 18
million Americans.
[0004] There are two types of sleep apnea: central and obstructive.
Central sleep apnea, which is relatively rare, occurs when the
brain fails to send the appropriate signal to the breathing muscles
to initiate respirations, e.g., as a result of brain stem injury or
damage. Mechanical ventilation is the only treatment available to
ensure continued breathing.
[0005] Obstructive sleep apnea (OSA) is far more common. It is one
of the several entities that make up the broader group of sleep
disordered breathing (SDB). This group of disorders ranges from
habitual snoring to OSA. Normally, the muscles of the upper part of
the throat keep the airway open to permit air flow into the lungs.
When the muscles of the upper airway relax and sag, the relaxed
tissues may vibrate as air flows past the tissues during breathing,
resulting in snoring. Snoring affects about half of men and 25
percent of women--most of whom are age 50 or older.
[0006] In more serious cases, the airway becomes blocked, making
breathing labored and noisy, or even stopping it altogether. In a
given night, the number of involuntary breathing pauses or "apneic
events" can be quite frequent. These breathing pauses are almost
always accompanied by snoring between apnea episodes, although not
everyone who snores has OSA.
[0007] Lack of air intake into the lungs results in lower levels of
oxygen and increased levels of carbon dioxide in the blood. The
altered levels of oxygen and carbon dioxide alert the brain to
resume breathing and cause arousal. The frequent interruptions of
deep, restorative sleep often lead to early morning headaches,
excessive daytime sleepiness, depression, irritability, and
learning and memory difficulties.
[0008] The medical community has become aware of the increased
incidence of heart attacks, hypertension and strokes in people with
moderate or severe obstructive sleep apnea. It is estimated that up
to 50 percent of sleep apnea patients have high blood pressure.
[0009] Upon an apneic event, the sleeping person is unable to
continue normal respiratory function and the level of oxygen
saturation in the blood is reduced. The brain will sense the
condition and cause the sleeper to struggle and gasp for air.
Breathing will then resume, often followed by continued apneic
events. There are potentially damaging effects to the heart and
blood vessels due to abrupt compensatory swings in blood pressure.
Upon each event, the sleeping person will be partially aroused from
sleep, resulting in a greatly reduced quality of sleep and
associated daytime fatigue.
[0010] Although some apneic events are normal in all humans, the
frequency of blockages will determine the seriousness of the
disease and opportunity for health damage. When the incidence of
blockage is frequent, corrective action should be taken.
II. Sleep and the Anatomy of the Upper Airway
[0011] As FIGS. 1A and 1B show, the upper airway consists of a
conduit that begins at the nasal valve, situated in the tip of the
nose, and extends to the larynx. Although all tissue along this
conduit is dynamic and responsive to the respiratory cycle, only
the pharyngeal conduit structures--the tissues in the region of the
airway that starts behind the nasal cavity and ends in its
connections to the supraglottic larynx--is totally collapsible. The
pharyngeal structures and individual anatomic components within
this region include the pharyngeal walls; the base of the tongue;
the vallecula; the hyoid bone and its attachments; the soft palate
with uvula, the palatine tonsils with associated pillar tissue; and
the epiglottis.
[0012] The cross sectional area of the upper airway varies with the
phases of the respiratory cycle. At the initiation of inspiration
(Phase I), the airway begins to dilate and then to remain
relatively constant through the remainder of inspiration (Phase
II). At the onset of expiration (Phase III) the airway begins to
enlarge, reaching maximum diameter and then diminishing in size so
that at the end of expiration (Phase IV), it is at its narrowest,
corresponding to the time when the upper airway dilator muscles are
least active, and positive intraluminal pressure is lowest. The
upper airway, therefore, has the greatest potential for collapse
and closure at end-expiration. Schwab R J, Goldberg A N. Upper
Airway Assessment: Radiographic and other Imaging Techniques.
Otolaryngol Clin North Am 1998; 31:931-968.
[0013] Sleep is characterized by a reduction in upper airway
dilator muscle activity. For the individual with obstructive sleep
apnea (OSA) and perhaps the other disorders which comprise much of
the group of entities called obstructive sleep-disordered breathing
(SDB), it is believed that this change in muscle function causes
pharyngeal narrowing and collapse. Two possible etiologies for this
phenomenon in OSA patients have been theorized. One is that these
individuals reduce the airway dilator muscle tone more than
non-apneics during sleep (the neural theory). The other is that all
individuals experience the same reduction in dilator activity in
sleep, but that the apneic has a pharynx that is structurally less
stable (the anatomic theory). Both theories may in fact be
contributors to OSA, but current studies seem to support that OSA
patients have an intrinsically structurally narrowed and more
collapsible pharynx. Isono S. Remmers J, Tanaka A Sho Y, Sato J,
Nishino T. Anatomy of Pharynx in Patients with Obstructive Sleep
Apnea and in Normal Subjects. J Appl Physiol 1997:
82:1319-1326.
[0014] Although anatomic closure is often accentuated at specific
sites, such as the velopharyngeal level [Isono, Ibid], studies of
closing pressures [Isono, Ibid] supports dynamic fast MRI imaging
that shows narrowing and collapse usually occurs along the entire
length of the pharynx. Shellock F G, Schatz C J, Julien P,
Silverman J M, Steinberg F, Foo TKF, Hopp M L, Westbrook P R.
Occlusion and Narrowing of the Pharyngeal Airway in Obstructive
Sleep Apnea: Evaluation by Ultrafast Spoiled GRASS M R Imaging. Am
J of Roentgenology 1992:158:1019-1024.
III. Prior Treatment Modalities
[0015] To date, the only modality that addresses collapse along the
entire upper airway is mechanical positive pressure breathing
devices, such as continuous positive airway pressure (CPAP)
machines. All other modalities, such as various surgical procedures
and oral appliances, by their nature, address specific sectors of
the airway (such as palate, tongue base and hyoid-vallecula
levels), but leave portions of pharyngeal wall untreated. This may
account for the considerably higher success rate of CPAP over
surgery and appliances in controlling OSA. Although CPAP, which in
essence acts as an airway splint for the respiratory cycle, is
highly successful, it has some very significant shortcomings. It
can be cumbersome to wear and travel with, difficult to accept on a
social level, and not tolerated by many (for reasons such as
claustrophobia, facial and nasal mask pressure sores, airway
irritation). These factors have lead to a relatively poor long-term
compliance rate. One study has shown that 65% of patients abandon
their CPAP treatment in 6 months.
[0016] The need remains for simple, cost-effective devices,
systems, and methods for reducing or preventing sleep disordered
breathing events.
SUMMARY OF THE INVENTION
[0017] One aspect of the invention provides devices, systems and
methods that employ static and/or kinetic force to fixate or brace
tissue in targeted pharyngeal structures and individual anatomic
components within the pharyngeal conduit, or within other anatomic
structures. When used in the pharyngeal conduit, the devices,
systems, and methods can serve to impede tissue collapse, when
imminent, to maintain patency of the pharyngeal conduit. When used
elsewhere, the devices, systems, and methods can serve different
purposes, e.g., to assist in closing anatomic pathways.
[0018] In one embodiment, the devices, systems, and methods include
at least one implanted structure. The implanted structure is sized
and configured to remodel native tissue conditions within the
targeted tissue region, by altering existing morphology and/or
motility and/or shape of tissue that, if not altered, could lead to
tissue collapse, particularly during the inspiration phase of the
respiratory cycle. The implanted structure establishes tissue
conditions that flexibly fixate or brace the tissue, to resist the
collapse of tissue along the pharyngeal conduit when imminent,
i.e., during sleep, but without significantly affecting the native
tissue at times when tissue collapse is not imminent. The fixation
or bracing function of the implanted structure can be accomplished
by either static means, or kinetic means, or a combination
thereof.
[0019] The targeted pharyngeal structures and individual anatomic
components within this region can include, e.g., the pharyngeal
walls; the base of the tongue; the vallecula; and the soft palate
with uvula.
[0020] Another aspect of the invention provides devices, systems,
and methods that brace or fixate tissue in targeted pharyngeal
structures and/or individual anatomic components within the
pharyngeal conduit by use of a pressure chamber, which is sized and
configured to be located outside of the pharyngeal conduit and to
hold a pressure that is less than atmospheric pressure. In one
embodiment, the pressure chamber is sized and configured to hold a
pressure that is less than a minimum pressure condition experienced
in the pharyngeal conduit during a respiration cycle. The pressure
chamber can be sized and configured, e.g., to be worn about a
neck.
[0021] The devices, systems, and methods can be used to treat
airway collapse and increased airway resistance associated with the
entire spectrum of obstructive sleep-disordered breathing. The
devices, systems, and methods can also be used to lend upper airway
support in neurological associated dystonic disorders.
[0022] Other features and advantages of the invention shall be
apparent based upon the accompanying description, drawings, and
claims.
DESCRIPTION OF THE DRAWINGS
[0023] FIGS. 1A and 13 are anatomic views of the upper airway in a
human, showing certain pharyngeal structures and individual
anatomic components within the pharyngeal conduit, FIG. 1A
comprising a lateral view and FIG. 13 is a superior view taken
generally along line 1B-1B in FIG. 1.
[0024] FIG. 2A shows in a diagrammatic way a force system that uses
implanted structures to fixate or brace tissue in targeted
pharyngeal structures and individual anatomic components within the
pharyngeal conduit.
[0025] FIG. 2B shows in a diagrammatic way a system that uses
pressure to fixate or brace tissue along the pharyngeal
conduit.
[0026] FIGS. 3A to 3C show an implanted static force structure of a
type shown in FIG. 2A that includes a material injected into a
targeted tissue region.
[0027] FIGS. 4A to 4D show an implanted static force structure of a
type shown in FIG. 2A that includes a material injected into an
expandable container implanted in a targeted tissue region.
[0028] FIGS. 5A and 5B show an implanted static force structure of
a type shown in FIG. 2A that is formed from a pre-shaped material,
FIG. 5B showing the structure implanted in the vallecula for
purposes of illustration.
[0029] FIGS. 6A to 6F show various embodiments of an implanted
static force structure of a type shown in FIG. 2A that is formed
from an array of individual, spaced apart implants that move
together as a result of tissue compression to resist tissue
collapse along the pharyngeal conduit.
[0030] FIGS. 7A and 7B show an implanted kinetic force structure of
a type shown in FIG. 2A that is formed from a spring-loaded
material, FIG. 5B showing the structure implanted in the pharyngeal
wall for purposes of illustration.
[0031] FIGS. 7C and 7D show an implanted kinetic force structure of
a type shown in FIG. 2A that is formed from an array of individual,
spring-loaded structures that are hinged together to resist tissue
collapse along the pharyngeal conduit.
[0032] FIGS. 8A(1)-8A(3) and 8B to 8D show an implanted kinetic
force structure of a type shown in FIG. 2A that is shaped due to
magnetic forces, FIGS. 8C and 8D showing the structure implanted in
the pharyngeal wall for purposes of illustration, and FIG. 8D
showing the structure juxtaposed with another magnetic structure
implanted in the base of the tongue.
[0033] FIGS. 9A and 9B show an implanted kinetic force structure of
a type shown in FIG. 2A that includes a shape-memory material that
assumes a predetermined shape in response to an applied activation
energy, FIG. 9A showing the structure before shape activation, and
FIG. 9B showing the structure after shape activation.
[0034] FIGS. 10A to 10D show an implanted kinetic structure of the
type shown in FIGS. 9A and 9B implanted, for the purpose of
illustration in a pharyngeal wall, FIG. 10C showing the structure
being shape activated by use of an external collar, and FIG. 10D
showing the structure being shape activated by use of a wand
inserted in the oral cavity.
[0035] FIGS. 11A and 11B show an implanted kinetic force structure
of a type shown in FIG. 2A that includes a shape-memory
ferromagnetic alloy that assumes a predetermined shape in response
to an applied magnetic field, FIG. 11A showing the structure before
shape activation, and FIG. 11B showing the structure after shape
activation.
[0036] FIGS. 12A to 12E show an implanted kinetic force structure
of a type shown in FIG. 2A that includes an array of soft
ferromagnetic materials that, when magnetized, assumes a
predetermined shape.
[0037] FIG. 13 shows an implanted static and/or kinetic force
structure of a type shown in FIG. 2A that carries a protective
material.
[0038] FIGS. 14A and 14B show an implanted static and/or kinetic
force structure of a type shown in FIG. 2A that is fixed to a
vertebra.
[0039] FIG. 15 show an implanted static and/or kinetic force
structure of a type shown in FIG. 2A that carries a tissue
in-growth surface.
[0040] FIGS. 16A and 16B and FIGS. 17A to 17C show static and/or
kinetic force structures of a type shown in FIG. 2A implanted in
horizontal arrays in targeted pharyngeal structures and individual
anatomic components within the pharyngeal conduit.
[0041] FIGS. 18A to 18C show static and/or kinetic force structures
of a type shown in FIG. 2A implanted in vertical arrays in targeted
pharyngeal structures and individual anatomic components within the
pharyngeal conduit.
[0042] FIGS. 19A and 19B show static and/or kinetic force
structures of a type shown in FIG. 2A implanted in mixed vertical
and horizontal arrays and in mixed non-horizontal and non-vertical
arrays in targeted pharyngeal structures and individual anatomic
components within the pharyngeal conduit, with fixation to a
vertebra.
[0043] FIGS. 20A and 20B show an implanted static and/or kinetic
force structure of a type shown in FIG. 2A that is fixed to a
vertebra.
[0044] FIG. 21 shows an illustrative embodiment of a system of the
type shown in FIG. 2A that includes static and/or kinetic force
structures implanted in the pharyngeal wall and adjacent anatomic
structures such as the tongue, vallecula, and soft palate.
[0045] FIGS. 22A to 22E shows an illustrative embodiment of a
system of the type shown in FIG. 2A that includes static and/or
kinetic force structures implanted in the tongue and adjacent
anatomic structures.
[0046] FIGS. 23A and 23B show a pressure chamber system of a type
shown in FIG. 2B.
[0047] FIGS. 24A to 24C show an illustrative surgical procedure for
the implantation of a static and/or kinetic structure of the type
shown in FIGS. 14A and 14B and FIGS. 19A and 19B, during which the
structure is fixed to a vertebra.
DETAILED DESCRIPTION
[0048] Although the disclosure hereof is detailed and exact to
enable those skilled in the art to practice the invention, the
physical embodiments herein disclosed merely exemplify the
invention, which may be embodied in other specific structure. While
the preferred embodiment has been described, the details may be
changed without departing from the invention, which is defined by
the claims.
I. Systems to Fixate or Brace Tissue
[0049] A. Implanted Force Systems
[0050] FIG. 2A shows in a diagrammatic way a force system 10 that,
in use, fixates or braces tissue in targeted pharyngeal structures
and individual anatomic components within the pharyngeal conduit
using one or more implanted structures 12. The force system 10
thereby impedes tissue collapse, when imminent, to maintain patency
of the conduit. The system 10 can be used to treat airway collapse
and increased airway resistance associated with the entire spectrum
of obstructive sleep-disordered breathing. The system 10 can also
be used to lend upper airway support in neurological associated
dystonic disorders.
[0051] In one basic form, the force system 10 comprises at least
one fixation or bracing structure 12 (shown in FIG. 2A), which is
sized and configured to be implanted in a targeted tissue region
within the pharyngeal conduit. The size and configuration of the
implanted structure 12 are selected to remodel native tissue
conditions within the targeted tissue region, by altering existing
morphology and/or motility and/or shape of tissue that, if not
altered, could lead to tissue collapse, particularly during the
respiratory cycle. The implanted structure 12 establishes tissue
conditions that fixate or brace the tissue, to resist collapse
along the pharyngeal conduit when imminent, i.e., during sleep, but
without significantly stiffening the native tissue at times when
tissue collapse is not imminent.
[0052] The targeted pharyngeal structures and individual anatomic
components within this region can include the pharyngeal walls; the
base of the tongue; the vallecula; the soft palate with uvula; the
palatine tonsils with associated pillar tissue; and the epiglottis.
These anatomic regions are shown in FIGS. 1A and 1B. Representative
examples of embodiments of magnetic force systems 10 in certain
targeted pharyngeal structures and individual anatomic components
within the pharyngeal conduit will be described in greater detail
later.
[0053] The fixation or bracing function of the implanted structure
12 can be accomplished by static means. The static means conditions
the tissue by virtue of inherent material properties and shape of
the structure 12. For example, a given static implanted structure
12 can take the form of a fluid or slurry that is injected into
tissue to form a gel or a solid matrix having a shape and/or
material properties that apply the static fixation or bracing force
to adjacent tissue. A static implanted structure 12 can also take
the form of a pre-shaped metal and/or polymer and fabric and/or
textile and/or ceramic structure having inherent material
properties and shape that, once implanted, conditions the tissue.
In either situation, the static conditioning remodels the
morphology and/or motility and/or shape of adjacent tissue.
Representative embodiments of force systems 10 comprising implanted
static structures 12 will be described in greater detail later.
[0054] The fixation or bracing function of the implanted structure
12 can also be accomplished by kinetic means. The kinetic means
exerts dynamic forces that react to kinetic forces within tissue.
The reactive dynamic forces can be generated, e.g., by magnetic
field forces and/or spring-like mechanical properties and/or
elastic mechanical properties. The reactive dynamic forces not only
impart a desired shape to the implant, but also imparting a dynamic
resistance to or bias against a change in the shape. In this
arrangement, for example, the implanted kinetic structure 12 can
comprise a metal and/or plastic and/or fabric and/or textile and/or
ceramic material that possesses a desired spring constant or
elastic loading to continuously exert a dynamic reactive force,
e.g., like a mechanical spring. Implanted kinetic structures 12 can
also be made from a metal and/or plastic and/or fabric and/or
ceramic material, which selectively assumes a shaped, elastically
loaded condition in response to an activating force, for example,
magnetism or temperature conditions or electrical energy or
electromagnetic force. The reactive dynamic forces exerted impart a
desired new morphology and/or motility and/or shape to adjacent
tissue, and also resist a change in these conditions.
Representative embodiments of force systems 10 comprising kinetic
implanted structures 12 will be described in greater detail
later.
[0055] The fixation or bracing function of the implanted structure
12 imparts improved comfort, tolerance, and bio-acceptance to the
implanted structure for the patient. The fixation or bracing
function is achieved without indiscriminate dampening (i.e.,
stiffening) the spring constant of native tissue in the pharyngeal
conduit (which is not desirable). The fixation or bracing function
is achieved due to the controlled application of static and/or
kinetic forces that push or pull on tissue, without themselves
imparting stiffness to the tissue in the pharyngeal conduit. The
size and configuration of the implanted structures are selected
with the ease and bio-comfort of implantation in mind, while at the
same time providing sufficient static and/or kinetic forces to
resist tissue collapse when collapse is imminent, taking into
account the anatomy of the region of implantation and orientation
of other components of the system 10. The implanted structures 12
thereby provide conformability, tolerance, and comfort for the
patient, without significantly dampening the spring constant of
native tissue.
[0056] Prior to implanting a given structure 12, tissue in the
targeted tissue region may be dilated, e.g., by use of a trocar or
expandable structure, e.g., a balloon or inflatable structure, to
open a tissue space to receive the structure. During dilation, the
tissue space may be deliberately sized and shaped, so that the
resulting implanted structure best conforms to the size, shape, and
physical characteristics to bring about the desired physiologic
response.
[0057] B. Pressure Chamber Systems
[0058] FIG. 2B shows in a diagrammatic way a pressure chamber
system 14 that, in use, fixates or braces tissue in targeted
pharyngeal structures and individual anatomic components within the
pharyngeal conduit by altering the differential between internal
pressure existing within the pharyngeal conduit (P1 in FIG. 2B) and
external pressure existing outside the pharyngeal conduit (P2 in
FIG. 2B). More particularly, the pressure chamber system 14 lowers,
in a localized region surrounding all or a portion of the
pharyngeal conduit, the external pressure to a pressure condition
(P2) that is less than atmospheric pressure and desirably less than
the minimum expected pharyngeal pressure (P1), which typically
occurs during the inhalation phase of the respiratory cycle. The
pressure chamber system 14 desirably creates in this localized
region a pressure differential that impedes tissue collapse to
maintain patency of the conduit. The purpose of the pressure
chamber system 14 is to desirably nullify the vector sum of the
extralumenal forces on the conduit, to make it de-compressive.
These forces are created by atmospheric pressure, gravity,
contractive forces caused by upper airway muscle activity, and
inward forces caused by subatmospheric luminal pressure generated
during inhalation.
[0059] Like the force system 10, the pressure chamber system 14 can
be used to treat airway collapse and increased airway resistance
associated with the entire spectrum of obstructive sleep-disordered
breathing. The pressure chamber system 14 can also be used to lend
upper airway support in neurological associated dystonic
disorders.
[0060] In one basic form, the pressure chamber system 14 comprises
at least one external pressure chamber 16 (shown in FIG. 2B), which
is sized and configured to be worn by an individual, when desired,
about a targeted tissue region or regions within the pharyngeal
conduit. The targeted pharyngeal structures and individual anatomic
components within this region can include the pharyngeal walls; the
base of the tongue; the vallecula; the soft palate with uvula; the
palatine tonsils with associated pillar tissue; and the
epiglottis.
[0061] The pressure chamber 16 establishes a localized pressure
condition (P2) about the targeted tissue region that is less than
atmospheric pressure and desirably less than the minimum-expected
pressure condition present in the pharyngeal conduit (P1). Exposed
to a localized pressure differential that is more negative than
ambient conditions, tissue along the pharyngeal conduit resists
collapse when collapse is imminent, i.e., upon inhalation during
sleep. The pressure chamber 16 can be removed during waking
hours.
[0062] Illustrative embodiments of implanted force systems 10 and
external pressure chamber systems 14 will now be described.
II. Illustrative Implanted Static Structures Useable with the Force
System
[0063] A. Injected Fluids and/or Slurries
[0064] As FIGS. 3A to 3C show, an implanted static structure 12 can
include an injected material 18 comprising one or more
biocompatible liquid components, or one or more solid biocompatible
components carried in one or more liquid biocompatible components.
The material 18 can be injected as a liquid or slurry into a
targeted tissue region, e.g., by a syringe 22 or the like (as FIG.
3B shows), which can comprise, e.g., the tongue, the vallecula, a
pharyngeal wall, or the soft palate/uvula. In one arrangement, upon
mixing, the components cross-link, polymerize, or otherwise
chemically react to create an in situ biocompatible, non-liquid,
static mechanical implant structure 12 (as FIG. 3C shows).
Implanted static structures 12 formed in situ from injected
materials 18 are well suited for implantation in targeted
pharyngeal structures and other anatomic components within the
pharyngeal conduit.
[0065] Prior to injection of the material, tissue in the targeted
tissue region may be dilated (see FIG. 3A), e.g., by use of a
trocar or expandable structure, to open a tissue space TS to
receive the in situ-setting fluid or slurry material 18. During
dilation, the tissue space TS may be deliberately sized and shaped,
so that the resulting implant material 18 injected into it will
possess the size, shape, and physical characteristics to bring
about the desired physiologic response.
[0066] The biocompatible liquid component may comprise, e.g., an
Elastin.TM. media. Alternatively, the liquid component may comprise
an oil or low viscosity liquid that is biocompatible to impart the
desired new morphology and/or motility and/or shape to surrounding
tissue. The solid component may be a polyvinyl acetate (PVA) or
foam that is appropriately sealed to provide biocompatibility.
Other materials such as silicone rubber, elastomeric polymers and
polytetrafluoroethylene (Teflon.RTM. Material, from DuPont) may
also be selected. Alternatively, a powder, small beads, or shavings
of solid material can be mixed with a slurry or liquid.
[0067] As FIG. 3C shows, the injected liquid or slurry may be
formulated to set in situ, to form an implanted static implant 12,
possessing the shape, position and mechanical properties to impart
the desired new morphology and/or motility and/or shape to
surrounding tissue.
[0068] Alternatively (see FIGS. 4A to 4D), the fluid or slurry
material 18 may be injected into an expandable container 20 (FIG.
4A) that is itself implanted in a targeted tissue region (FIG. 4B).
As FIG. 4A shows, the container is desirably pre-shaped, to assume
the desired inflated shape, position, and mechanical
properties.
[0069] Once suitably implanted, the container 20 is inflated by
infusion of the fluid or slurry material 18, which is dispensed,
e.g., from a syringe 22 or the like (see FIG. 4C). In one
arrangement, the injected liquid or slurry material 18 may be
formulated to set in situ within the container 20 (see FIG. 4D),
the container and its contents serve as an implanted static implant
12, possessing the shape, position and mechanical properties to
impart the desired new morphology and/or motility and/or shape to
surrounding tissue, or to otherwise achieve the desired physiologic
response. It should be appreciated that, when an implanted
container 20 is used to house the injected material 18, saline or a
fluid or slurry that does not set or cure in situ may be used to
form an implanted kinetic structure 12. Furthermore, the fluid or
slurry material 18 may be formulated to be injected as a gel that
need not set or cure to perform its intended function.
[0070] The container 20 may comprise a bioresorbable material, such
as polyglycolic acid, a polymer used for resorbable sutures and
other devices within the body. In this arrangement, once the
container 20 is resorbed, only the in situ-setting fluid of slurry
material 18 will remain to serve as the implanted kinetic structure
12.
[0071] B. Shaped Static Structures
[0072] As FIG. 5A shows, an implanted static structure 12 can be
formed--e.g., by bending, shaping, joining, machining, molding,
braiding, assembly, or extrusion--from a biocompatible metallic
and/or polymer and/or fabric and/or textile and/or ceramic
material, or a metallic and/or polymer and/or fabric and/or textile
and/or ceramic material that is suitably coated, impregnated, or
otherwise treated with a material to impart biocompatibility, or a
combination of such materials. For example, pre-shaped, static
structures 12 can be formed from acetal resins (Delrin.RTM.
material, Celcon.RTM. material), Teflon.RTM. material, and/or
silicone rubber compounds.
[0073] Implanted static structures 12 formed from pre-shaped
metallic and/or polymeric and/or fabric and/or textile and/or
ceramic materials are well suited for implantation in the tongue,
the vallecula, or soft palate, as well as other targeted pharyngeal
structures and other anatomic components within the pharyngeal
conduit. FIG. 5B shows the pre-shaped static structure 12
implanted, for the purpose of illustration in the vallecula. Once
suitably implanted in a targeted tissue region, the static implant
12 possesses the shape, position and mechanical properties to
impart the desired new morphology and/or motility and/or shape to
surrounding tissue, or to otherwise achieve the desired physiologic
response.
[0074] C. Bending Structures
[0075] As FIG. 6A shows, an implanted static structure 12 can be
formed by an array of individual implants 24 sized and configured
to be spaced-apart along an arc. The radius of the arc and the
spacing between the individual implants 24 along the arc are
predetermined, so that individual implants 24 will move
successively closer together as the tissue develops the morphology
and/or motility and/or shape conducive to collapse. The radius of
the arc and spacing distance are pre-selected so that, before
tissue collapse occurs (see FIG. 6B), spacing between the
individual implants 24 will diminish, compressing tissue between
them. The spacing between individual implants 24 may disappear, as
the implants 24 come into contact with or abutment against each
other. When tissue compression occurs, the array of implants 24
possesses a composite shape, position and mechanical properties to
impart a desired new morphology and/or motility and/or shape to
surrounding tissue, to resist tissue collapse. Still, when collapse
of the tissue is not imminent (see FIG. 6A), the implants 24 occupy
a spaced-apart, non-contiguous relationship, which does not
compress tissue or significantly affect the morphology and/or
motility and/or shape to surrounding tissue.
[0076] As FIGS. 6C and 6D show, individual, spaced-apart implants
24 within the array may be linked together, e.g., by plastic and/or
metal and/or fabric and/or textile and/or ceramic material 26, to
help keep the implants 24 in a desired spatial relationship. The
mechanical properties of the linking material 26 also affects the
mechanical properties of the array prior to tissue compression.
[0077] As FIGS. 6E and 6F show, the implant 12 can comprise a body
28 having one or more preformed hinge points 30. When collapse of
the tissue is not imminent (see FIG. 6E), the hinge points 30 are
open, and the body 28 does not significantly affect the morphology
and/or motility and/or shape to surrounding tissue. However (see
FIG. 6F), the hinge points 30 close as the tissue develops the
morphology and/or motility and/or shape conducive to collapse. With
the hinge points 30 closed, the body 28 possesses the shape,
position and mechanical properties to impart a desired new
morphology and/or motility and/or shape to surrounding tissue, to
resist tissue collapse.
[0078] When the hinge points 30 are closed, the mechanical
properties of the material of the body 28 determine the magnitude
of the resistance to tissue collapse. The material of the hinged
body 28 (which can comprise plastic and/or metal and/or fabric
and/or textile and/or ceramic) can be stiff or flexible, or elastic
or in-elastic, or combinations thereof. If elastic, the hinged body
28 can function, when the hinge points 30 are closed, as a kinetic
implant structure 12, as will be described below. The hinge points
30 can also be varied in terms of closure angle and spacing, to
provide along the length of the hinged body 28, regions of
differing resistance to closure. The hinged body 28 can also be
made of materials having different mechanical properties, to
provide along the length of the hinged body regions of differing
flexibility and/or elasticity.
III. Illustrative Implanted Kinetic Structures Useable with the
Force System
[0079] A. Continuously Kinetic
[0080] 1. Shaped Springs
[0081] As FIG. 7A shows, an implanted kinetic structure 12 can
exert a dynamic reactive force by virtue of elasticity or spring
bias. The elasticity or spring bias places the kinetic structure
under normal compression, which imparts a desired shape to the
structure and also provides an elastic resistance to a change in
that shape.
[0082] Spring-biased kinetic structures 12 formed from pre-shaped
metallic and/or polymeric and/or fabric and/or textile and/or
ceramic materials are well suited for implantation in the tongue,
the vallecula, soft palate, a pharyngeal wall, as well as other
targeted pharyngeal structures and other anatomic components within
the pharyngeal conduit. FIG. 6B shows an illustrative spring-biased
kinetic structure implanted, for purposes of illustration, in a
pharyngeal wall.
[0083] The structure 12 is formed, e.g., from a shaped elastic or
super-elastic plastic or metal or alloy material 32. The structure
12 includes a preformed biased toward a desired shape, which, in
the illustrated embodiment is shown to be a curved configuration
conducive to bracing the tissue in the pharyngeal wall against
collapse into the airway. Movement of the tissue into the airway is
kinetically resisted by the spring-biased elasticity of the
structure 12. The structure 12 is shown in FIGS. 7A and 7B to be a
flat strip. However, the structure can be wire-formed, or tubular,
or possess virtually any other cross sectional configuration.
[0084] As FIGS. 7C and 7D show, individual spring-like structures
36 exerting dynamic reactive force by virtue of elasticity or
spring bias can be joined by hinge points 34. When collapse of the
tissue is not imminent (see FIG. 7C), the hinge points 34 are open,
and the hinged bodies 36 do not significantly affect the morphology
and/or motility and/or shape to surrounding tissue. However (see
FIG. 7D), the hinge points 34 close as the tissue develops the
morphology and/or motility and/or shape conducive to collapse. With
the hinge points 34 closed, and the bodies 35 collectively assume a
spring-loaded condition to impart a desired new morphology and/or
motility and/or shape to surrounding tissue, to resist tissue
collapse. When the hinge points 34 are closed, the collective
elastic or spring-biased mechanical properties of the individual
spring-loaded bodies 36 kinetically resist tissue collapse. As
previously discussed with respect to the hinged body 28 shown in
FIGS. 6E and 6F, the hinge points 34 can be varied in terms of
closure angle and spacing, to provide along the length of the
hinged body 36, regions of differing resistance to closure. The
individual spring-like structures 36 linked by the hinges 34 can
also be made of materials having different elastic or spring-biased
properties, to provide along the length of the hinged body regions
of differing kinetic resistance to tissue collapse.
[0085] 2. Shaped Magnetic Arrays
[0086] An implanted kinetic structure 12 can also exert a dynamic
force by virtue of magnetic forces. The magnetic forces impart a
desired shape to the implant 12, while also providing a magnetic
field resistance to or bias against shape change. FIGS. 8A(1), (2),
and (3) and 8B show an illustrative magnetically shaped array of
permanent magnets 38 mounted on a flexible, inelastic carrier 40.
The carrier 40 may carry one or more rows of magnets 38.
[0087] The permanent magnets 38 on the carrier 40 are characterized
as showing resistance to external demagnetizing forces once being
magnetized. Examples of known permanent magnet materials include
alloys of Neodymium-Iron-Boron (NdFeB), alloys of
Aluminum-Nickel-Cobalt (AlNiCo), and Samarium Cobalt (SmCo). These
materials are typically coated with Nickel. An electromagnet
(current flowing through a coil of wire) can be substituted for a
permanent magnet.
[0088] The permanent magnets 38 on the carrier 40 each generate an
external magnetic field. As FIG. 8A(1) shows in diagrammatically,
the permanent magnets 38 are arranged on the carrier 40 with like
magnetic poles facing each other (North-North or South-South).
According to physical laws, poles of like polarity repel each other
with a magnetic force. The force of magnetic repulsion depends on
the strength of the magnets and the distance between the poles. The
permanent magnets 38 on the carrier 40 can also be arranged with
the same poles facing the carrier 40, as shown in FIGS. 8A(2) and
8A(3). According to magnetic force calculations and finite element
analysis, permanent magnets 38 like that shown in FIG. 8A(1), (2),
or (3)--having the same poles facing the same direction--will repel
each other if they are arranged in close proximity.
[0089] As FIG. 8B shows, the magnetic repulsion between neighboring
magnets 38 bends the flexible carrier 40. Furthermore, the
repelling force between neighboring magnets 38 gets stronger as
distance between the poles decreases, and it is this continuous,
dynamic force that resists straightening of the carrier 40 out of
its magnetically set shape. This dynamic, magnetically induced
resistance to shape change, in turn, exerts a dynamic force on
neighboring tissue, to impart a desired new morphology and/or
motility and/or shape to the tissue, together with a corresponding
resistance to change in this condition, to achieve the desired
physiologic response.
[0090] The carrier 40 is desirably made from a material that
imparts biocompatibility, durability, and flexibility to the
magnetic array. The carrier 40 may be made, e.g., of a flexible or
semi-rigid material such as polycarbonate, silicone rubber,
polyurethane, etc, or a flexible or semi-rigid plastic and/or metal
and/or fabric and/or textile and/or ceramic material. The material
of the carrier 40 can enclose the magnets 38, or the magnets 38 can
be carried on the surface of the carrier 40. The spacing between
the magnets 38 on or within the carrier 40 provides the requisite
flexibility desired. The individual magnets 38 can have various
geometries--rectangular, cylindrical, spherical, oval, etc.--as
long as the desired physiologic response is achieved.
[0091] Flexible magnetically shaped structures 12 are well suited
for implantation in targeted pharyngeal structures and other
anatomic components within the pharyngeal conduit, e.g., the
tongue, vallecula, soft palate/uvula, and a pharyngeal wall. FIG.
8C shows magnetically shaped structures 12 implanted, for the
purpose of illustration, in pharyngeal walls. A magnetically shaped
structure 12 can implanted alone, e.g., in a pharyngeal wall, or in
conjunction with other magnetically shaped structures, as FIG. 8C
shows.
[0092] As FIG. 8D shows, one or more magnetically shaped structures
12 in the pharyngeal wall can be juxtaposed to one or more
permanent magnet structures 42 implanted in the posterior of the
tongue. The magnets in the structures 12 and the magnet structures
42 in the tongue possess the same magnetic orientation. The
repelling force between the opposing tongue magnet(s) and
pharyngeal wall structures shape the pharyngeal wall structures in
the manner described above. This juxtaposition of magnets resists
collapse of the airway as the tissue relaxes and comes into
proximity, particularly during Phase IV of the respiratory cycle.
Other arrangements are possible, as will be described in greater
detail later.
[0093] B. Selectively Kinetic
[0094] 1. Shape Memory Structures
[0095] An implanted kinetic structure 12 (see FIG. 9A) can exert a
dynamic force by virtue of a selectively activated shape memory. In
this arrangement, the implanted kinetic structure 12 is made from a
class of materials 44 that have the ability to return to remembered
shapes when activated by an external stimulus (see FIG. 9B). The
structures 12 can be made from, e.g., shape memory alloys, shape
memory polymers, or ferromagnetic shape memory alloys. Illustrative
embodiments follow.
[0096] a. Shape Memory Materials
[0097] An implanted kinetic structure 12 can comprise a shape
memory metal material 44 that assumes a predetermined, remembered
shape in response to an applied activation energy 46 (see FIG. 9B).
The activation energy 46 can comprise, e.g., electrical energy,
mechanical energy, thermal energy, electromagnetic energy, acoustic
energy, or light energy.
[0098] The shape memory material 44 can comprise an alloy, e.g.,
Nitinol.RTM. alloy (an alloy consisting of nickel and titanium),
and copper based alloys, most commonly Cu--Zn--Al and Cu--Al--Ni.
The shape memory material 44 can also comprise a shape memory
polymer.
[0099] FIG. 10A shows an implanted kinetic structure 12 made, e.g.,
of a Nitinol.RTM. shape memory alloy. Shape memory kinetic
structures 12 are well suited for implantation in the tongue, the
vallecula, or the soft palate, as well as other targeted pharyngeal
structures and other anatomic components within the pharyngeal
conduit. In FIG. 10A, the structure 12 is implanted, for the
purposes of illustration, in the pharyngeal wall. As shown in FIG.
10A, the structure 12 possesses relatively compliant mechanical
properties at certain temperature conditions, which is sometimes
called the soft martensitic phase. In response to increased
temperature conditions, the structure 12 assumes less compliant
mechanical properties (see FIG. 10B), accompanied by accelerated
shape change. This is sometimes called the hard austenitic phase.
In this phase (as shown in FIG. 10B), the structure 12 provides a
dynamic resistance to shape change. In the illustrated embodiment,
the change in temperature conditions is brought about by an
external activation energy source 46 that is used when activation
is desired. The activation energy source 46 can be worn by the
individual (see FIGS. 10B and 10C), e.g., carried by a collar 48
secured about the neck of the individual. The activation source 46
(see FIG. 10D) can also be carried on a wand 50 that is placed in
the oral cavity when activation is desired. The activation source
46 can comprise a source of heat. Alternatively, the activation
source 46 can comprise an electrical field source to resistively
heat the structure, or a mechanical energy source. Alternatively,
magnetic alloys could be used that heat up when exposed to an
external alternating magnetic field. As FIG. 10A shows, the
relatively compliant mechanical properties of the structure return
when the structure 12 is cooled sufficiently to return to the soft
martensitic phase. For example, the individual could drink a
sufficiently cool or cold liquid, or use the wand 50 set at a
sufficiently cool temperature to return the structure to a
relatively compliant condition.
[0100] b. Shape Memory Ferromagnetic Alloys
[0101] An implanted kinetic structure 12 can comprise a shape
memory ferromagnetic alloy 52 that assumes a predetermined,
remembered shape in response to a magnetic field 54. The alloy 52
can comprise, e.g., Ni--Mn--Ga alloys close to the stoichiometric
composition Ni.sub.2MnGa.
[0102] Shape memory ferromagnetic kinetic structures 12 are well
suited for implantation in the tongue, the vallecula, the soft
palate, or a pharyngeal wall, as well as other targeted pharyngeal
structures and other anatomic components within the pharyngeal
conduit. FIG. 11A shows an implanted kinetic structure 12 made of a
shape memory ferromagnetic memory alloy 52 implanted, for the
purposes of illustration, in the base of the tongue. As FIG. 11A
shows, the structure 12 possesses relatively compliant mechanical
properties in the absence of an external magnetic field 54. In
response to exposure to an external magnetic field 54 (see FIG.
11B), the structure 12 assumes less compliant mechanical
properties, accompanied by pronounced shape change. In this phase,
the structure 12 provides a stiffening resistance to shape change.
In the illustrated embodiment, the external magnetic field 54 is
brought about permanent magnets or an electro-magnet worn by the
individual, e.g., carried by a collar 48 secured about the neck of
the individual, in the manner shown in FIG. 10C. The source of the
magnetic field 54 can also be carried on a wand 50 in the manner
shown in FIG. 10D. In the absence of the external magnetic field 54
(as FIG. 11A shows), the relatively compliant mechanical properties
of the structure 12 return.
[0103] 2. Selective Magnetic Activation
[0104] As FIGS. 12A and 12B show, an implanted kinetic structure 12
can comprise an array of soft ferromagnetic materials 58 mounted on
a flexible carrier 56. A soft ferromagnetic material 58 is a
material that can be demagnetized very easily, once having been
magnetized. In other words, a soft ferromagnetic material 58
retains almost no residual magnetism after the magnetizing force is
removed. Soft ferromagnetic materials 58 have very high
permeability and saturation magnetization, but very low intrinsic
coercivity. Soft magnetic materials 58 can be attracted by a
permanent magnet or an electromagnet.
[0105] Examples of known soft ferromagnetic materials 58 include
Iron (Fe); Nickel (Ni); Permendur; MuMetal, low-carbon steels,
Iron-Cobalt alloys (Fe--Co); silicon steels; and amorphous
alloys.
[0106] The soft ferromagnetic materials 58 can be machined, laser
cut, chemically etched, or EDM manufactured into magnetic blocks
and encased, packaged, or otherwise arranged on the flexible
carrier 56 to form a magnetic array structure 12, as FIGS. 12A and
12B show. In the absence of a magnetic force 60, the array
structure 12 possesses compliant mechanical properties.
[0107] In this arrangement (see FIG. 12C), when activation of the
soft ferromagnetic array structure 12 is desired, an external
source of magnetic force 60 (which can comprise, e.g., a second
array with permanent magnets, or a single permanent magnet, or an
electromagnet) can be donned by the individual (e.g., in the collar
48 shown in FIG. 10C or wand 50 shown in FIG. 10D). Exposure of the
soft ferromagnetic array structure 12 to the source of magnetism 60
causes the array to become magnetic. The external magnetic force 60
is sized and configured to make adjacent surfaces of soft magnetic
blocks 58 have unlike poles, and are thereby attracted to one
another. This attraction will case the carrier 56 to bend (as FIG.
12C shows), until the magnetic blocks 58 come into contact with
each other. This attraction and contact will be maintained until
the source of magnetism 60 is removed or reduced in intensity. This
continuous, dynamic magnetic force will resists straightening of
the carrier 56. This dynamic, magnetically induced resistance to
shape change, in turn, exerts a dynamic force on neighboring
tissue, to impart a desired new morphology and/or motility and/or
shape to the tissue, together with a corresponding resistance to
change in this condition, to achieve the desired physiologic
response. Selectively magnetically shaped structures 12 are well
suited for implantation in the tongue, vallecula, soft palate, a
pharyngeal wall, as well as in other targeted pharyngeal structures
and other anatomic components within the pharyngeal conduit. FIG.
12E shows a magnetically shaped structure 12 of the type shown in
FIGS. 12A and 12B implanted, for the purpose of illustration, in
the soft palate. Exposure of the structure 12 to a source of
magnetism 60 bends the structure 12 in the manner shown in FIG.
12C, pulling the soft palate forward.
[0108] As FIG. 12D shows, the soft ferromagnetic material 58 can be
mounted to the carrier 56 to cause serpentine bending. Serpentine
bending can be achieved by affixing similar ferrous blocks 58 on
the opposite surface of the flexible carrier 56, displaced axially
from the blocks on the first surface. The flexible carrier 58 may
be produced with an offset between the two areas if it is desirable
to maintain a thin overall thickness of the assembly.
IV. Biocompatibility
[0109] As FIG. 13 shows, a given implanted static or kinetic
structure 12 of whatever form or configuration can be coated,
plated, encapsulated, or deposited with a selected protective
material 62. The protective material 62 is selected to provide a
corrosion resistant and biocompatible interface, to prevent
interaction between the structure and tissues/fluids of the body.
The protective material 62 is also desirably selected to form a
durable tissue interface, to provide longevity to the structure,
and thereby provide resistance to structural fatigue and/or
failure. The protective material 62 can be selected among various
types of materials known to provide the desired biocompatibility,
resistance to corrosion, and durability. For example, the
protective material 62 can comprise gold and/or titanium material
plated, deposited, or otherwise coated upon the structure. As
another example, the protective material 62 can comprise a parylene
coating. As other examples, the protective material 62 can comprise
a silicone polymer, a non-toxic epoxy, a medical grade
polyurethane, or a U.V. curable medical acrylic co-polymer.
[0110] The protective material 62 may also incorporate
anticoagulants and/or antibiotics.
V. Fixation of Static or Kinetic Implants
[0111] A. Use of Mechanical Fixation Materials
[0112] The position of implanted structures 12 can be fixed against
migration in a targeted tissue region within the pharyngeal conduit
using conventional mechanical fixation materials and techniques
known in the surgical arts, e.g., non-resorbable sutures, screws,
staples, adhesives, or cements such as polymethyl methacrylate
(PMMA) cement. For example, the structures 12 can include preformed
apertures 64 to accommodate the fixation material, i.e., sutures,
screws or staples. Fixation to tissue enhances the fixation or
bracing function of the implanted static or kinetic structure.
[0113] The tissue to which a given implant is fixed can include
soft tissue in the pharyngeal walls, the base of the tongue; the
vallecula; the soft palate with uvula; the palatine tonsils with
associated pillar tissue, and the epiglottis.
[0114] The tissue can also include bone within the pharyngeal
conduit, e.g., a hyoid bone or a vertebra, as will be next
described.
[0115] B. Fixation to a Vertebra
[0116] In some cases, implantation of one or more structures 12,
with fixation to bone, may be desirable. As FIG. 14A shows, one or
more given implanted static or kinetic structures 12 may be fixed
to one or more vertebrae with fixation elements 66 such as bone
screws and/or adhesives and/or bone cements. As FIG. 20A also
shows, such structures 12 can be fixed, e.g., at or near the
pedicles. Alternatively (as FIG. 14B shows), one or more implanted
static or kinetic structures 12 may be fixed with a fixation
element 66 such as a bone screw to other regions of the vertebra. A
single fixation point may be used to secure multiple implanted
static or kinetic structures.
[0117] With vertebra fixation, several static or kinetic structures
12 may be oriented horizontally in a single row or in a fan or in a
vertically stacked relationship along the pharyngeal conduit (as
shown in FIG. 20B), in an angular path within a lateral pharyngeal
wall (as shown in FIG. 20A).
[0118] In this way, fixation or bracing of the lateral pharyngeal
wall can be achieved by using implanted static or kinetic structure
or structures 12 that are stabilized with a vertebral column bone
anchor. Fastening to bone enhances the fixation or bracing function
of the implanted static or kinetic structure 12.
[0119] In representative procedure for implanting a pharyngeal wall
implant 12 or other pharyngeal wall device that is fixed to a
vertebral body (see FIGS. 24A to 24C): (1) a patient is positioned
in the Rose tonsillectomy position (supine, head extended), and
with the pharynx exposed using a Crowe Davis, or similar
tonsillectomy mouth retractor; (2) the anterior aspect of the
cervical vertebra is identified along the posterior pharyngeal
wall; (3) a small transverse incision (see FIG. 24A) is made just
lateral to midline, and deepened to the body of a cervical
vertebra, exposing bone; (4) the implant 12 can be inserted through
this incision (as FIG. 24A shows) and tunneled submucosally along
the lateral pharyngeal wall, using manual palpation along the
mucosa for guidance; (5) when proper placement is established, the
implant 12 is released; (6) a new implant 12 (see FIG. 24B) is then
loaded through the same small incision, angling the placement
downward. In this fashion, an array of implants 12 can be placed
within the submucosal space along the pharyngeal wall. The proximal
ends of all the implants 12 placed are configured with a rounded
ring (like a flat washer). All of these rings are then placed on
the shaft of a self tapping screw (see FIG. 24C) which is then
secured to the vertebral column as the bone anchor. The area is
irrigated with antibacterial solution and the small incision is
closed in two layers (periosteum, then mucosa). An identical
procedure is then carried out on the contralateral pharyngeal side,
establishing two separate sets of arrayed submucosal wall
implants.
[0120] C. Tissue in-Growth Surfaces
[0121] In addition to any of the just-described tissue fixation
methodologies, the implanted static or kinetic structure can
include a tissue in-growth surface 68 (see FIG. 15). The surface 68
provides an environment that encourages the in-growth of
neighboring tissue on the implanted structure. Tissue in-growth is
defined as the filing of pores in an implanted material with
cellular material. As in-growth occurs, the implanted structure 12
will become securely anchored, resisting migration or extrusion
from the tissue. The tissue in-growth surface 68 thus enhances
tissue adhesion and stabilization, and thereby further stabilizes
and fixes the position of the implanted structure 12 in the
targeted implantation site.
[0122] The tissue in-growth surface 68 can be formed in various
ways. For example, the surface can comprise an open cellular or
fibrous structure, biologically inert in nature and known to
support in-growth by body tissue. One material that exhibits this
characteristic is expanded PTFE (polytetrafluoroethylene or
Teflon.RTM.--DuPont). This material may be prepared by radiation
bombardment to cause the structure of the material to become
fractured and fibrous in nature. The resulting material is open and
porous, providing fissures into which fluids may enter and to which
body tissue can attach and grow. Other such inert polymers and even
metals (such as nickel titanium--Nitinol.RTM.) when treated or
coated to provide a granular or fibrous surface, may offer a
substrate for tissue in-growth. An alternative form of the
in-growth matrix may be an open celled polymeric foam (e.g., PVA
foam) in place of a material that must be irradiated to attain the
open fibrous or granular nature.
[0123] The in-growth surface 68 can also comprise, e.g., woven or
knitted Dacron.RTM. (PET) fabric placed on a substrate of
polydimethylsiloxane (PDMS) or polyurethane (PU); metallic surface
structures created by electroform processing; a sintered metal
surface (e.g., stainless steel, platinum, iridium, or alloys
thereof); parylene coatings; or diffusion limited aggregated
silicones. The in-growth surface can also comprise mechanical
structures, such as spike, staples, times, coils, or perforations
of appropriate dimensions associated with the implant. The implant
may also include compounds to promote coagulation and/or
antibiotics to prevent infection, used alone or in combination with
the in-growth surface 68.
[0124] It may be desirable to mechanically anchor the implant 12
while allowing in-growth to occur. Temporary anchoring may be
accomplished by use of resorbable sutures, screws or other
mechanical fasteners made of resorbable materials such as
polyglycolic acid or other similar compounds. Tissue adhesives
and/or tissue cements such as PMMA may also be used to provide
tissue adhesion, fixation, and stabilization.
[0125] Complete tissue in-growth is determined by the percentage of
the material that has been infiltrated by the cellular material.
With pore sizes from 100 micrometers to 500 micrometers, blood
vessels can be formed. With pore sizes of 10 micrometers to 100
micrometers, cells to small capillaries can form.
VI. Orienting Implanted Static or Kinetic Structures
[0126] The orientation of the static or kinetic structures can vary
according to the particular anatomy of the targeted tissue region
and its environs.
[0127] A. Horizontal Orientation
[0128] For example, the particular anatomy and tissue mass of the
targeted tissue region may lend itself to the implantation of the
static or kinetic structures 12 in a generally horizontal plane.
With respect to anatomic landmarks, horizontal arrays extend either
laterally (from side to side) or anterior-to-posterior (front to
back), following the natural morphology of the tissue.
[0129] For example (see FIG. 16A), the anatomy and the tissue mass
of the tongue accommodates implantation of a horizontal array of
static or kinetic structures 12, either laterally in the base of
the tongue, or anterior-to-posterior along one or both sides of the
tongue, or both. As FIG. 16B shows, horizontal arrays of static or
kinetic structures 12 can be implanted in stacked or staggered
fashion on the posterior of the tongue, at different elevations
along the pharyngeal conduit.
[0130] As another example (see FIG. 17A), the anatomy and the
tissue mass of the lateral pharyngeal wall accommodates
implantation of a horizontal array of multiple static or kinetic
structures 12 following the morphology of the posterior and lateral
pharyngeal walls. In the pharyngeal wall (see FIG. 17B), one or
more shaped static or kinetic structures 12 can remodel tissue
along a substantial portion of the airway, from the spinal column
to the base of the tongue.
[0131] As FIG. 17C shows, horizontal arrays of multiple static or
kinetic structures 12 can be implanted in stacked or staggered
fashion within the lateral pharyngeal wall. The structures may be
discontinuous or form concentric bands about the pharyngeal wall at
different elevations along the pharyngeal conduit.
[0132] B. Vertical Orientation
[0133] The particular anatomy and tissue mass of the targeted
tissue region may lend itself to the implantation of multiple
static or kinetic structures 12 in a generally vertical plane. With
respect to anatomic landmarks, vertical arrays extend in a superior
(cephalad)-to-inferior (caudal) direction, following the natural
morphology of the tissue mass.
[0134] For example (see FIG. 18A), the anatomy and the tissue mass
of the pharyngeal wall accommodates implantation of a vertical
array of multiple static or kinetic structures 12 following the
morphology of opposite lateral pharyngeal walls.
[0135] As FIG. 18B shows, vertical arrays of multiple static or
kinetic structures 12 can be implanted either end-to-end or side-by
side within the lateral pharyngeal wall.
[0136] As FIG. 18C shows, the anatomy and the tissue mass of the
base of the tongue and the vallecula accommodate implantation of a
vertical array of multiple static or kinetic structures 12
following the morphology of these anatomic components within the
pharyngeal conduit.
[0137] C. Other Orientations
[0138] The particular anatomy and tissue mass of the targeted
tissue region may lend itself to the implantation of multiple
static or kinetic structures 12 in both a generally horizontal
plane and a generally vertical plane.
[0139] For example (see FIG. 19A), the anatomy and the tissue mass
of the pharyngeal wall accommodates implantation of vertical arrays
of multiple static or kinetic structures 12 with horizontal arrays
of static or kinetic structures 12 along the elevation of the
pharyngeal conduit. This implantation pattern makes possible the
formation of dynamic bracing or fixation forces that facilitate the
physiologic objective of resisting tissue collapse along the
pharyngeal conduit.
[0140] The particular anatomy and tissue mass of the targeted
tissue region may lend itself to the implantation of multiple
static or kinetic structures 12 in angular planes (i.e., not
horizontal or not vertical planes).
[0141] For example (see FIG. 19B), the anatomy and the tissue mass
of the pharyngeal wall accommodates implantation of angular,
non-horizontal and non-vertical arrays of multiple static or
kinetic structures 12. This complex implantation pattern makes
possible the formation of dynamic bracing or fixation forces that
facilitate the physiologic objective of resisting tissue collapse
along the pharyngeal conduit.
VII. Illustrative Implanted Force Systems
[0142] Based upon the foregoing discussions, a practitioner can
select and assemble static and/or kinetic structures 12 in various
ways to create systems 10 of different configurations to achieve
the desired physiologic response. The static and/or kinetic
structures 12 are well suited for implantation within the
pharyngeal walls (with or without fixation to a vertebral body);
the base of the tongue; the vallecula; and the soft palate/uvula.
Representative examples of embodiments of magnetic force systems 10
in certain targeted pharyngeal structures and individual anatomic
components within the pharyngeal conduit will be described in
greater detail now.
A. Implants within the Pharyngeal Wall and Adjacent Structures
[0143] FIG. 21 shows an illustrative embodiment of a system 10 that
includes static and/or kinetic structures 12 that are implanted in
a vertical arrays on opposite lateral sides of the pharyngeal wall
(with or without fixation to a vertebral body), the base of the
tongue, the vallecula, and the soft palate/uvula. The structures 12
can be selected among the various static and kinetic types
previously discussed. It should be appreciated that stacked
horizontal arrays, or a combination of horizontal and vertical
arrays, or angular arrays could be used. Each structure remodels
tissue in its vicinity, providing bracing or fixation forces that
facilitate the physiologic objective of resisting tissue collapse
along the pharyngeal conduit, when imminent. It should be
appreciated that static and/or kinetic structures 12 need not be
implanted precisely in the manner shown or at every anatomic site
shown to achieve the desired physiologic objective.
[0144] B. Implants within the Tongue and Adjacent Structures
[0145] FIG. 22A shows another illustrative embodiment of a system
10 that includes static and/or kinetic structures 12 that are
implanted on opposite lateral sides in the base of tongue as well
as in the soft palate. The structures 12 can be selected among the
various static and kinetic types previously discussed. It should be
appreciated that other arrays, or a combination of arrays arrays
could be used. Each structure 12 remodels tissue in its vicinity,
providing bracing or fixation forces that facilitate the
physiologic objective of resisting tissue collapse along the
pharyngeal conduit. It should be appreciated that static and/or
kinetic structures 12 need not be implanted precisely in the manner
shown or at every anatomic site shown to achieve the desired
physiologic objective.
[0146] FIGS. 22B and 22C show another illustrative embodiment of a
system 10 that includes one or more selectively kinetic structures
12 that are implanted across the base of the tongue. In FIG. 22B,
the implanted structure 12 is shown in a non-activated
configuration. In FIG. 22C, the selectively kinetic structure 12 is
subject to a suitable activation force (as previously described),
causing the implanted structure to assume a desired activated
configuration. In this configuration, the implanted structure
remodels the base of the tongue. The configuration shown in FIG.
22C includes a depression in the middle of the tongue base, which
resists closure of the airway during sleep, and a prominence 72 on
the right and left lateral sides of the tongue base, which serve to
press against the lateral oropharyngeal tissue, holding the tongue
in an anterior position.
[0147] FIGS. 22D and 22E show another illustrative embodiment of a
system 10 that includes one or more selectively kinetic structures
12 that are implanted in the posterior of the tongue and vallecula.
In FIG. 22D, the implanted structures 12 are shown in a
non-activated configuration, extending horizontally along the
posterior of the tongue and the vallecula. In FIG. 22E, the
selectively kinetic structures 12 are subject to a suitable
activation force (as previously described), causing the implanted
structures to assume a desired activated configuration. In this
configuration shown in FIG. 22E, the implanted structures remodel
the posterior of the tongue and vallecula, creating a depression 70
that runs vertically down the posterior surface of the tongue and
the vallecula.
VIII. Illustrative Structures Useable with the Pressure Chamber
System
[0148] FIGS. 23A and 23B show an illustrative embodiment of a
pressure chamber system 14. The system 14 includes a collar 74 that
is sized and configured to be removably worn about the neck of an
individual when the desired physiologic effect is desired, e.g.,
during sleep (as FIG. 23A shows).
[0149] The collar 74 carries a pressure-retaining chamber 16. When
the collar 74 is worn, the chamber 16 encircles all or a portion of
the pharyngeal conduit (see FIG. 23B). The chamber 16 may comprise
an elastic material for comfort.
[0150] An air pump 76 has an inlet that communicates with the
chamber 16 and an outlet that communicates with the ambient
environment. The air pump 76 can be carried by the collar 74 (as
shown), or it can be located remote from the collar, e.g., bedside,
and coupled by tubing to the air chamber 16. The air pump 76 can
comprise, e.g., a diaphragm pumping mechanism, or a reciprocating
piston mechanism, or a centrifugal (turbine) air-moving
mechanism.
[0151] The air pump 76 may be manually operated, or a power source
78 may drive the air pump 76. The power source 78 can be, e.g., an
electric motor that can be plugged into a conventional electrical
receptacle, or be battery-powered, or both (in which case the
battery can be rechargeable). When driven, the air pump 76 draws
air from the chamber 16, to establish within the chamber 16 a
pressure condition that is less than atmospheric.
[0152] A regulator 80 may be coupled to govern operation of the air
pump 76 to establish and maintain a desired subatmospheric pressure
condition within the chamber 16. The desired pressure condition is
selected to be less than atmospheric pressure and is desirably less
the minimum pressure condition expected experienced in the
pharyngeal conduit, which is typically encountered during the
inhalation phase of the respiration cycle. The pressure selected
desirably nullifies the vector sum of the extralumenal forces,
which are created by the interaction of atmospheric pressure,
gravity, the contractive forces within the tissue due to upper
airway muscle activity, and the inward forces generated by
subatmospheric luminal pressure generated during inhalation. It is
believed that the pressure condition established within the chamber
16 should be at least -1 cm H.sub.2O and desirable at least -10 cm
H.sub.2O. The pressure created by the system 14 desirably also
takes into account different anatomical structural differences of
individual airways.
[0153] The system 14 can also include some form of physiologic
feedback control for the air pump. In this arrangement, the system
includes a monitor or sensor 82 to sense fluctuations of pharyngeal
pressure during the respiration cycle. When the pharyngeal pressure
meets or exceeds a selected threshold minimum pressure, the monitor
82 sends a control signal to the pump 76, to activate the pump 76.
The pump 76, when activated, operates to maintain a desired
pressure condition within the chamber 16 while sensed pharyngeal
pressure is below the threshold. The pump 76, when activated, could
also operate to maintain a desired pressured differential between
pressure in the chamber 16 and the sensed pharyngeal pressure while
sensed pharyngeal pressure is below the threshold. Once pharyngeal
pressure exceeds the threshold, the monitor 82 sends a control
signal to deactivate the pump 76. In this way, the system 14
conditions tissue to resist collapse when respiratory conditions
are most conducive to collapse, but otherwise does not affect the
tissue morphology and/or motility and/or shape. The pressure
chamber 16 can also serve to reduce tissue vibration and be used in
the treatment of snoring.
[0154] Other forms of physiologic feedback control can be used. For
example, airflow can be measured during the respiratory cycle,
and/or the expansion/contraction of the chest can be monitored
during the cycle. Chamber pressure can be varied to response to
requirements dictated by the respiratory cycle.
[0155] The above-described embodiments of this invention are merely
descriptive of its principles and are not to be limited. The scope
of this invention instead shall be determined from the scope of the
following claims, including their equivalents.
* * * * *