U.S. patent application number 12/246071 was filed with the patent office on 2009-02-12 for methods, apparatuses, and systems for reducing intraocular pressure as a means of preventing or treating open-angle glaucoma.
This patent application is currently assigned to KOLIS SCIENTIFIC, INC.. Invention is credited to Beth Friedland, Keith Gausmann, Steve Grenon, John Jans, Donald R. Korb, Timothy R. Willis.
Application Number | 20090043365 12/246071 |
Document ID | / |
Family ID | 42100906 |
Filed Date | 2009-02-12 |
United States Patent
Application |
20090043365 |
Kind Code |
A1 |
Friedland; Beth ; et
al. |
February 12, 2009 |
METHODS, APPARATUSES, AND SYSTEMS FOR REDUCING INTRAOCULAR PRESSURE
AS A MEANS OF PREVENTING OR TREATING OPEN-ANGLE GLAUCOMA
Abstract
Embodiments include methods, apparatuses, and systems for
reducing elevated intraocular pressure (IOP) in a patient to either
prevent or treat open-angle glaucoma. Heat is applied to the
trabecular meshwork in the patient's eye without damaging proteins
in the trabecular meshwork. The application of heat to the
trabecular meshwork has the effect of relaxing or loosening protein
clogs or other inhibitors in the trabecular meshwork, which are
either reducing or obstructing of the outflow of aqueous humor,
thereby increasing the patient's IOP and causing ocular
hypertension (OHT). By loosening or relaxing clogs or other
inhibitors in the trabecular meshwork, the outflow path for aqueous
humor is increased or restored, which can lower IOP and either
prevent or treat glaucoma. Force may also be applied to the
patient's eye to apply pressure to the trabecular meshwork to
further assist in the loosening or relaxing of clogs or other
inhibitors in the trabecular meshwork.
Inventors: |
Friedland; Beth; (Raleigh,
NC) ; Korb; Donald R.; (Boston, MA) ; Grenon;
Steve; (Durham, NC) ; Jans; John;
(Hillsborough, NC) ; Gausmann; Keith; (Cary,
NC) ; Willis; Timothy R.; (Raleigh, NC) |
Correspondence
Address: |
WITHROW & TERRANOVA, P.L.L.C.
100 REGENCY FOREST DRIVE, SUITE 160
CARY
NC
27518
US
|
Assignee: |
KOLIS SCIENTIFIC, INC.
Morrisville
NC
|
Family ID: |
42100906 |
Appl. No.: |
12/246071 |
Filed: |
October 6, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11541291 |
Sep 29, 2006 |
|
|
|
12246071 |
|
|
|
|
11434033 |
May 15, 2006 |
|
|
|
11541291 |
|
|
|
|
11541308 |
Sep 29, 2006 |
|
|
|
11434033 |
|
|
|
|
11434054 |
May 15, 2006 |
|
|
|
11541308 |
|
|
|
|
12015558 |
Jan 17, 2008 |
|
|
|
11434054 |
|
|
|
|
60700233 |
Jul 18, 2005 |
|
|
|
60700233 |
Jul 18, 2005 |
|
|
|
60880850 |
Jan 17, 2007 |
|
|
|
Current U.S.
Class: |
607/108 |
Current CPC
Class: |
A61B 2018/00642
20130101; A61B 18/10 20130101; A61F 2007/0004 20130101; A61H 1/008
20130101; A61B 18/04 20130101; A61N 7/00 20130101; A61F 2007/0059
20130101; A61F 2007/0071 20130101; A61B 2018/00791 20130101; A61B
2018/048 20130101; A61F 9/00781 20130101; A61B 2018/046
20130101 |
Class at
Publication: |
607/108 |
International
Class: |
A61F 7/00 20060101
A61F007/00 |
Claims
1. A method of lowering a patient's intraocular pressure,
comprising the steps of: transferring heat to a trabecular meshwork
of a patient's eye to a temperature level to loosen or relax one or
more clogs in the trabecular meshwork to improve or restore an
outflow path for aqueous humor through the trabecular meshwork; and
maintaining the heat transfer to the trabecular meshwork for a
period of time.
2. The method of claim 1, wherein transferring heat to the
trabecular meshwork comprises transferring heat through a sclera
and cornea of the patient's eye and to the trabecular meshwork.
3. The method of claim 2, wherein transferring heat to the
trabecular meshwork comprises directing the heat in a direction in
line with the trabecular meshwork and out of line with an iris and
pupil of the patient's eye.
4. The method of claim 1, further comprising measuring an
intraocular pressure level of the patient's eye prior to performing
the steps of transferring heat and maintaining the heat.
5. The method of claim 2, further comprising measuring an
intraocular pressure level of the patient's eye after performing
the steps of transferring heat and maintaining the heat.
6. The method of claim 4, further comprising: diagnosing the
intraocular pressure level in the patient's eye; performing the
steps of transferring heat and maintaining the heat based on the
diagnosing of the intraocular pressure level in the patient's
eye.
7. The method of claim 1, further comprising measuring an
intraocular pressure level of the patient's eye after performing
the steps of transferring heat and maintaining the heat.
8. The method of claim 1, further comprising discontinuing the
transfer of heat to the trabecular meshwork.
9. The method of claim 8, further comprising, after the step of
discontinuing the transfer of heat to the trabecular meshwork:
measuring an intraocular pressure level of the patient's eye;
diagnosing the intraocular pressure level in the patient's eye; and
determining if the steps of transferring heat and maintaining heat
should be performed again based on the diagnosis.
10. The method of claim 1, wherein the period of time is between 10
and 120 minutes.
11. The method of claim 1, wherein the temperature of the heat
transferred is such that the heat reaching the trabecular meshwork
is above body temperature.
12. The method of claim 11, wherein the temperature of the heat
reaching the trabecular meshwork is between approximately 40 to 44
degrees Celsius.
13. The method of claim 1, wherein the transfer of heat further
comprises applying the heat to an outer eyelid of the patient's eye
such that the heat is transferred through the outer eyelid and
through a sclera and lens of the patient's eye to the trabecular
meshwork.
14. The method of claim 13, wherein the temperature of the heat
applied to the outer eyelid of the patient's eye is between
approximately 40 and 48 degrees Celsius.
15. The method of claim 1, wherein the transfer of heat further
comprises applying the heat to a sclera of the patient's eye such
that the heat is transferred through the sclera and cornea of the
patient's eye to the trabecular meshwork.
16. The method of claim 15, wherein the temperature of the heat
applied to the sclera of the patient's eye is between approximately
38 and 45 degrees Celsius.
17. The method of claim 1, further comprising transferring a force
to the trabecular meshwork to apply a pressure to the trabecular
meshwork to assist in loosening or relaxing one or more clogs in
the trabecular meshwork to improve or restore the outflow path for
aqueous humor through the trabecular meshwork.
18. The method of claim 17, further comprising maintaining the
transfer of the force to the trabecular meshwork for a period of
time.
19. The method of claim 18, wherein the period of time for
maintaining the transfer of the force to the trabecular meshwork is
between approximately 10 and 120 minutes.
20. The method of claim 17, wherein transferring the force to the
trabecular meshwork further comprises applying a force to the
outside of the patient's eyelid that is transferred to the
trabecular meshwork.
21. The method of claim 20, wherein the force applied to the outer
eyelid is between approximately 10 and 500 mmHg.
22. The method of claim 20, wherein the force applied to the
outside of the patient's eyelid is a massaging force.
23. The method of claim 17, wherein the force transferred to the
trabecular meshwork is transferred simultaneously with the heat
transfer.
24. The method of claim 17, wherein the force transferred to the
trabecular meshwork is transferred after discontinuing the transfer
of heat to the trabecular meshwork.
25. The method of claim 1, wherein transferring heat to the
trabecular meshwork comprises transferring diffuse heat to the
trabecular meshwork.
Description
RELATED APPLICATIONS
[0001] The present application is a continuation-in-part of U.S.
patent application Ser. No. 11/541,291 filed on Sep. 26, 2006 and
entitled "METHOD AND APPARATUS FOR TREATING MEIBOMIAN GLAND
DYSFUNCTION EMPLOYING FLUID JET," which is a continuation-in-part
of U.S. patent application Ser. No. 11/434,033 filed on May 15,
2006 and entitled "METHOD AND APPARATUS FOR TREATING GLAND
DYSFUNCTION EMPLOYING HEATED MEDIUM," which claims priority to U.S.
Provisional Patent Application No. 60/700,233 filed on Jul. 18,
2005 and entitled "METHOD AND APPARATUS FOR TREATING GLAND
DYSFUNCTION," all of which are incorporated herein by reference in
their entireties.
[0002] The present application is also a continuation-in-part of
U.S. patent application Ser. No. 11/541,308 filed on Sep. 29, 2006
and entitled "MELTING MEIBOMIAN GLAND OBSTRUCTIONS," which is a
continuation-in-part application of U.S. patent application Ser.
No. 11/434,054 filed on May 16, 2006 and entitled "METHOD AND
APPARATUS FOR TREATING MEIBOMIAN GLAND DYSFUNCTION," which claims
priority to U.S. Provisional Patent Application No. 60/700,233
filed on Jul. 18, 2005 and entitled "METHOD AND APPARATUS FOR
TREATING GLAND DYSFUNCTION," all of which are incorporated herein
by reference in their entireties.
[0003] The present application is also a continuation-in-part of
U.S. patent application Ser. No. 12/015,558 filed on Jan. 17, 2008
and entitled "INNER EYELID TREATMENT FOR TREATING MEIBOMIAN GLAND
DYSFUNCTION," which claims priority to U.S. Provisional Patent
Application No. 60/880,850 filed on Jan. 17, 2007 and entitled
"METHOD AND APPARATUS FOR TREATING MEIBOMIAN GLAND OBSTRUCTIVE
DISEASE," all of which are incorporated herein by reference in
their entireties.
FIELD OF THE INVENTION
[0004] The present invention relates to methods and apparatuses for
reducing intraocular pressure (IOP) as a means of preventing or
treating open-angle glaucoma. More particularly, the methods and
apparatuses sustainably reduce intraocular pressure (IOP), which
causes ocular hypertension (OHT) or glaucoma and which is widely
believed to be a leading cause of blindness.
BACKGROUND OF THE INVENTION
[0005] Glaucoma is the name given to a group of eye diseases in
which the optic nerve at the back of the eye is slowly destroyed.
In some people, the damage may be caused by poor blood supply to
the vital optic nerve fibers, a weakness in the structure of the
nerve, or a problem in the health of the nerve fibers themselves.
However in most people, this damage is the result of a reduction or
blockage of circulation of aqueous or its drainage, known as
open-angle glaucoma. As illustrated in FIG. 1, aqueous humor 10
flows through the inside of the eye 12 and nourishes the lens 14,
the iris 16, and the inside 18 of the cornea 20. The aqueous humor
10 leaves the cornea 20 and enters into the trabecular meshwork 22,
which is the eye's "drain." The trabecular meshwork 22 contains
tiny holes or passages 24 that surround the iris 16. Normally, the
aqueous 10 flows freely through the trabecular meshwork 22 and into
Schlemm's canal 26, where it then enters back into the bloodstream.
However in open-angle glaucoma, if the trabecular meshwork 22
becomes clogged, more aqueous humor 10 flows into the eye 12 than
can freely drain out. As a result, intraocular pressure (IOP) can
rise, causing ocular hypertension (OHT). OHT is an important risk
factor for glaucoma, although other risk factors can contribute to
glaucoma, including reduced blood flow to the affected area of the
optic nerve.
[0006] It is important to reduce elevated IOP as quickly as
possible after diagnosis to either prevent the onset of glaucoma or
if glaucoma has already damaged the optic nerve and caused vision
loss, to prevent any further damage and vision loss. The importance
of lowering IOP to treat glaucoma is known. (See, Taban et al., The
Importance of Lowering Intraocular Pressure, Medscape
Ophthalmology, Feb. 20, 2008) Once IOP is lowered, a suitable
treatment is selected to keep IOP under control at normal levels.
Known treatments include medication, laser treatment, and surgery.
Patient factors such as age, general health, and stage of glaucoma,
as well as various socioeconomic and technologic factors may lead
to different recommendations for different patients. In the case of
medication, eyedrops and pills are the most comment treatments.
Both can be used to decrease the production of aqueous humor in the
eye, but side effects can occur, including headaches, eye
irritation, and/or blurred or dimmed vision. Further, the
effectiveness of medication diminish over time.
[0007] Laser treatment known as "trabeculoplasty" is another
accepted procedure for treatment of open-angle glaucoma if
medications inadequately control IOP levels. This procedure is
commonly performed using either a cw argon laser or a cw diode
laser. In this procedure, the laser energy is delivered
gonioscopically using a contact goniolens. As illustrated in FIG.
2, laser energy 28 emitted from a laser (not shown) is focused onto
a small diameter spot 30 on the trabecular meshwork 22. The laser
energy 28 heats the meshwork tissue 32 until a white spot (or laser
burn) is created. It is generally accepted that the laser burns
cause shrinkage in the trabecular meshwork tissue 32. This
shrinkage is believed to cause the meshwork tissue 32 disposed
between the laser burns to stretch and become more open, thereby
decreasing the resistance of the trabecular meshwork 22 to aqueous
humor outflow thus reducing IOP. If effective, trabeculoplasty may
reduce IOP by twenty to twenty-five percent. (See Taban et al., The
Importance of Lowering Intraocular Pressure, Medscape
Ophthalmology, Feb. 20, 2008)
[0008] Several issues can exist with laser trabeculoplasty. One
issue is that the IOP lowering effect tends to disappear over time.
IOP may only be adequately controlled for just a few years.
Successive treatment may be limited without risking coagulative
damage to the trabecular meshwork. Another issue that may be
encountered with laser trabeculoplasty is pressure spiking. In the
days following the trabeculoplasty procedure, the patient's IOP can
rise above pretreatment levels. This pressure spiking requires
careful monitoring and control. Other complications include iritis,
hyphema, and development of peripheral anterior synechiae.
[0009] Another accepted method for treatment of open-angle glaucoma
is invasive surgery. Trabeculectomy and tube shunts are the most
typical procedures performed. In trabeculectomy, the surgeon
removes a section of the limbal tissue underneath a scleral flap to
create a path for aqueous humor to drain out of the eye and into a
bleb formed by the conjunctiva to reduce IOP. Complications that
can occur from trabeculectomies including hypotony, flat chambers,
chorodial effusions, suprachoroidal hemorrhages, elevated IOP,
hyphema, cataract, and infection. Tube shunts are most commonly
used in open-angle glaucoma if trabeculectomy has failed. A tube is
placed in the anterior chamber that allows aqueous humor to flow to
an extraocular reservoir secured near the equator on the sclera to
reduce IOP. Complications of tube shunts include overfiltration,
tube-cornea touch, tube obstruction, tube erosion, tube migration,
and ocular motility disorders. Other less common surgical
interventions include ciliary body abalation,
endocyclophotocoagulation, or cyclecryotherapy.
[0010] There exists a need to provide a non-invasive method,
apparatus, and system for treating open-angle glaucoma which
results in longer term IOP control and without side effects or
issues that can arise from known methods, including medication,
laser treatment, and surgery.
SUMMARY OF THE EMBODIMENTS
[0011] Embodiments of the present invention include methods,
apparatuses, and systems for reducing intraocular pressure (IOP)
levels in a patient as a means of either preventing or treating
open-angle glaucoma. The breakthrough of the present invention is
that heat, when applied at a temperature above body temperature and
directed to the trabecular meshwork in the patient's eyes, can
sustainably reduce IOP. The application of heat to the trabecular
meshwork has the effect of loosening or relaxing protein clogs or
blockages or other inhibitors in the trabecular meshwork that may
either be reducing or obstructing of the outflow of aqueous humor
thereby increasing the patient's IOP as a result. Preferably, the
heat is directed to circumference area of the sclera in a line
towards the trabecular meshwork and outside or out of line with the
pupil and iris of the eye for safety reasons. This may also enable
higher temperatures of heat to be applied to compensate for any
heat transfer losses that may occur. The applied heat can be
diffuse and non-focused to direct heat energy to the trabecular
meshwork via intervening tissue.
[0012] Force can also applied to the patient's eye globe to apply
pressure to the trabecular meshwork. Pressure can further assist in
the loosening or relaxing of protein clogs or other inhibitors in
the trabecular meshwork. The force may be increased and decreased
continuously to provide a massaging force to the trabecular
meshwork. The relaxation of protein clogs or blockages or other
inhibitors has the effect of restoring the outflow of aqueous and
sustainably lowering IOP for treating open-angle glaucoma.
[0013] In one embodiment, a patient is checked for signs of ocular
hypertension (OHT) by first measuring the patient's IOP level. OHT
can lead to the development of glaucoma or be an indication that
glaucomatous eyes already exist in the patient. The patient's IOP
level is diagnosed to determine if the IOP level is elevated or at
an unsafe level. Normal IOP levels can vary with different patients
and can vary based on a variety of factors, such as time of day,
heart rate, respiration, exercise, fluid intake, systemic
medication, topical drugs, alcohol consumption, etc. IOP also
usually increases with age and thickness of their cornea, as
examples. The patient is then diagnosed to determine if their IOP
is elevated above their normal or expected IOP levels. If an
elevated IOP is determined to exist, treatment may be administered
in accordance with embodiments of the present invention. This
includes applying a combination of regulated heat and/or force,
including but not limited to a massaging force, to the patient's
eye globe such that the heat and massaging force is applied to the
trabecular meshwork. The temperature of the heat and/or the amount
of pressure generated by the force may be regulated according to
desired temperature and pressure profiles. Regulated heat and force
may be applied at the same time or in serial fashion. The regulated
heat and force may also be automatically applied by a device or
system, manually, or a combination of manual and automated
application. After heat and/or force are applied to the trabecular
meshwork for the prescribed amount of time, the heat and/or force
are removed from the trabecular meshwork. The patient's IOP is
subsequently measured. If the patient's IOP level has been reduced
to safe levels, treatment can end and a follow-up visit scheduled
to monitor the patient's IOP level. If the patient's IOP level is
not reduced to a safe level, treatment can be repeated during the
same session or at a later time, as prescribed by the attending
medical clinician or physician. Further, periodic follow-up visits
and treatments may be desired or required to maintain the patient's
IOP within safe levels.
[0014] A variety of devices may be used to apply heat and/or force
to trabelcular meshwork. A heating and force application device may
be employed that applies heat and force to the outside of the
patient's eyelid, wherein the heat and force are directed to and
applied to the trabecular meshwork. A heating and pressure
regulating device or system may be used to control heat and force
applied to the patient's eyelid. The heating and pressure
regulating device may be provided in the form of goggles or other
apparatus desired to fit over the patient's eye. A massaging force
may be provided in the form of a vibratory force or pressure, or
may be provided in the form of a gas or fluid jet that inflates and
deflates a bladder placed against the patient's eye to provide a
massaging force to the trabecular meshwork, as examples.
[0015] In another embodiment, a heat application device may be
provided in the form of a lens with an embedded heating element.
The heating element can be tightly regulated to prevent burning.
The lens is placed inside the patient's eyelid and over top the
sclera. The heating element contained inside the lens may be
located around the circumference of the lens such that heat is
applied proximate the trabecular meshwork but outside of the iris
and pupil. Directing heat directly into the area of the iris or
pupil may cause damage or may not allow the temperature of the heat
to be transferred at the most effective levels to the trabecular
meshwork. After heat is applied to the trabecular meshwork using
the lens, the lens may be removed such that a force, such as a
massaging force, can then be applied to the patient's eye to apply
a force to the trabecular meshwork. As discussed above, applying a
force to the trabecular meshwork can assist in the loosening or
relaxing of protein clogs or other inhibitors that are reducing or
preventing the outflow of aqueous humor through the trabecular
meshwork and through Schlemm's canal. Before force is applied, the
lens may be required to be removed since the lens structure may
obstruct an applied force from reaching the trabecular meshwork
when over top the patient's eye. Again, after treatment, the
patient's IOP is subsequently measured. If the patient's IOP level
has been reduced to safe levels, treatment can end and a follow-up
visit scheduled to monitor the patient's IOP level. If the
patient's IOP level is not reduced to a safe level, treatment can
be repeated during the same session or at a later time, as
prescribed by the attending medical clinician or physician.
Further, periodic follow-up visits and treatments may be desired or
required to maintain the patient's IOP within safe levels.
[0016] Those skilled in the art will appreciate the scope of the
present invention and realize additional aspects thereof after
reading the following detailed description of the preferred
embodiments in association with the accompanying drawing
figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The accompanying drawing figures incorporated in and forming
a part of this specification illustrate several aspects of the
invention, and together with the description serve to explain the
principles of the invention.
[0018] FIG. 1 is a close-up view of the lower front half of the eye
illustrating circulation and drainage of aqueous in the eye under
normal conditions;
[0019] FIG. 2 is a close-up view of the lower front half of the eye
illustrating opening drainage holes in the trabecular meshwork to
restore drainage and reduce intraocular pressure (IOP) in the
eye;
[0020] FIG. 3 is an exemplary eyelid temperature profile of an
inner and outer eyelid temperature versus time when heat is applied
to the exterior of the eyelid;
[0021] FIG. 4 is flow chart illustrating an exemplary process for
measuring, diagnosing, and treating elevated IOP levels to either
prevent or retard the further effect of open-angle glaucoma,
according to one embodiment;
[0022] FIG. 5 is block diagram of a trabecular meshwork heating and
force application device for treating open-angle glaucoma;
[0023] FIG. 6 is an expanded block diagram of a trabecular meshwork
heat and force application device of FIG. 5;
[0024] FIGS. 7-8 are block diagrams of a trabecular meshwork
heating control circuit that may be employed in the trabecular
meshwork heat and force application device of FIG. 6;
[0025] FIG. 9 is a goggle assembly for providing heat and massaging
force treatment to the trabecular meshwork to treat open-angle
glaucoma;
[0026] FIG. 10 is a close-up view of the goggle assembly of FIG.
9;
[0027] FIGS. 11-12 illustrate heating elements that may be used in
a trabecular meshwork heating application device;
[0028] FIG. 13 is a flow chart illustrating an embodiment of a
process for applying heat and vibratory force to the trabecular
meshwork to treat open-angle glaucoma;
[0029] FIGS. 14-16 illustrate various trabecular meshwork heat
application device assemblies that may be used to treat open-angle
glaucoma;
[0030] FIG. 17 is a perspective view of a trabecular meshwork heat
and force application device employing goggles, according to an
alternative embodiment;
[0031] FIGS. 18-19 are front and rear perspective views of the
goggles illustrated in FIG. 17;
[0032] FIG. 20 is a front perspective view taken from below and
showing the fluid delivery components of the trabecular meshwork
heat and massaging system illustrated in FIG. 17;
[0033] FIG. 21 is a rear perspective view of the fluid jet orifices
of the trabecular meshwork heat and force application device
illustrated in FIG. 17;
[0034] FIG. 22 is flow chart illustrating an alternative exemplary
process for measuring, diagnosing, and treating elevated IOP as a
symptom of open-angle glaucoma;
[0035] FIG. 23 is block diagram of a trabecular meshwork heating
control circuit for treating open-angle glaucoma according to the
exemplary process illustrated in FIG. 22;
[0036] FIG. 24 illustrates a trabecular meshwork heat application
device for treating open-angle glaucoma, according to an
alternative embodiment;
[0037] FIG. 25 illustrates a heating application component of the
trabecular meshwork heat application device illustrated in FIG.
24;
[0038] FIG. 26 illustrates the process of placing the heat
application component illustrated in FIG. 25 on the patient's eye
inside the eyelid to apply heat to the trabecular meshwork;
[0039] FIG. 27 illustrates a cross-sectional view of the heat
application component illustrated in FIGS. 25-26; and
[0040] FIG. 28 illustrates a system diagram of temperature control
and communication components of the trabecular meshwork heating
device illustrated in FIGS. 24-27.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] The embodiments set forth below represent the necessary
information to enable those skilled in the art to practice the
invention and illustrate the best mode of practicing the invention.
Upon reading the following description in light of the accompanying
drawing figures, those skilled in the art will understand the
concepts of the invention and will recognize applications of these
concepts not particularly addressed herein. It should be understood
that these concepts and applications fall within the scope of the
disclosure and the accompanying claims.
[0042] Embodiments of the present invention include methods,
apparatuses, and systems for reducing intraocular pressure (IOP)
levels in a patient as a means of either preventing or treating
open-angle glaucoma. The breakthrough of the present invention is
that heat, when applied at a temperature above body temperature and
directed to the trabecular meshwork in the patient's eyes, can
sustainably reduce IOP. The application of heat to the trabecular
meshwork has the effect of loosening or relaxing protein clogs or
blockages or other inhibitors in the trabecular meshwork that may
either be reducing or obstructing of the outflow of aqueous humor
thereby increasing the patient's IOP as a result. Preferably, the
heat is directed to circumference area of the sclera in a line
towards the trabecular meshwork and outside or out of line with the
pupil and iris of the eye for safety reasons. This may also enable
higher temperatures of heat to be applied to compensate for any
heat transfer losses that may occur. The applied heat can be
diffuse and non-focused to direct heat energy to the trabecular
meshwork via intervening tissue.
[0043] Force can also applied to the patient's eye globe to apply
pressure to the trabecular meshwork. Pressure can further assist in
the loosening or relaxing of protein clogs or other inhibitors in
the trabecular meshwork. The force may be increased and decreased
continuously to provide a massaging force to the trabecular
meshwork. The relaxation of protein clogs or blockages or other
inhibitors has the effect of restoring the outflow of aqueous and
sustainably lowering IOP for treating open-angle glaucoma.
[0044] In one embodiment, a patient is checked for signs of
glaucoma. Such signs can include ocular hypertension (OHT), which
can be measured by measuring the patient's IOP level, or other
factors such as reduced blood flow to the optic nerve area. OHT can
lead to the development of glaucoma or be an indication that
glaucomatous eyes already exist in the patient. The patient's IOP
level is diagnosed to determine if the IOP level is elevated or at
an unsafe level and/or if other glaucoma factors exist. Normal IOP
levels can vary with different patients and can vary based on a
variety of factors, such as time of day, heart rate, respiration,
exercise, fluid intake, systemic medication, topical drugs, alcohol
consumption, etc. IOP also usually increases with age and thickness
of their cornea, as examples. The patient is then diagnosed to
determine if their IOP is elevated above their normal or expected
IOP levels. If an elevated IOP and/or other glaucoma factors are
determined to exist, treatment may be administered in accordance
with embodiments of the present invention. This includes applying a
combination of regulated heat and/or force, including but not
limited to a massaging force, to the patient's eye globe such that
the heat and massaging force is applied to the trabecular meshwork.
The temperature of the heat and/or the amount of pressure generated
by the force may be regulated according to desired temperature and
pressure profiles. Regulated heat and force may be applied at the
same time or in serial fashion. The regulated heat and force may
also be automatically applied by a device or system, manually, or a
combination of manual and automated application. After heat and/or
force are applied to the trabecular meshwork for the prescribed
amount of time, the heat and/or force are removed from the
trabecular meshwork. The patient's IOP can be subsequently measured
as well as looking for other glaucoma factor signs. If the
patient's IOP level has been reduced to safe levels and/or other
glaucoma factors have been addressed to the satisfaction of the
physician or technician, treatment can end and a follow-up visit
scheduled to monitor the patient's IOP level and/or other glaucoma
factors. If the patient's IOP level is not reduced to a safe level
and/or other glaucoma factors are still of concern, treatment can
be repeated during the same session or at a later time, as
prescribed by the attending medical clinician or physician.
Further, periodic follow-up visits and treatments may be desired or
required to maintain the patient's IOP within safe levels.
[0045] The application of heat and/or massaging force to the
trabecular meshwork to lower IOP in a patient's eye in a sustained
manner was discovered as a result of conducting studies on
patients. The study consisted of approximately fifteen patients. In
the study, heat and pressure was applied to the patient's eye and
directed towards the trabecular meshwork. Because force was being
applied to the outside of the patient's eye globe as part of the
treatment, the treatment causing increased IOP levels was of
concern. Increased IOP levels can cause retinal damage thus
impacting the visual function of the eye. Thus, the patient's IOP
was measured before and after treatment to observe the results. The
inventors expected the patient's IOP to be the same or slightly
lower as a result of the treatment, because the massaging force was
applied for longer periods of time than, for example, the force
applied by a Honan balloon. A Honan balloon is a well-known device
that is applied for short periods of time to a patient's eyes to
reduce IOP just prior to surgery.
[0046] It was found that application of heat and massaging force to
the patient's eye did in some cases result in a reduced IOP
immediately following the procedure. It was then theorized that the
drop in IOP levels would be short lived, because for example, the
reduction in IOP levels as a result of employing the Honan balloon
on a patient only lasts for approximately 1 to 3 hours. However,
for some patients, the reduction in IOP levels lasted for several
months in some cases. This sustained reduction in IOP levels lead
the inventors to theorize that the patient may have been suffering
from abnormally elevated IOP levels that were either causing or
could cause glaucoma. An analysis was performed to determine the
reasons for the unexplained prolonged reduction in IOP levels as a
result of applying heat and massaging force to the patient's eye.
The analysis resulted as follows.
[0047] The application of heat and force to the patient's eye was
theorized to be applying heat and force to the trabecular meshwork.
FIG. 3 illustrates how the application of heat to the outside of
the patient's eyelid results in increased temperatures inside the
patient's eyelid at the actual eye, albeit with a temperature drop
occurring across the eyelid. FIG. 3 illustrates a treatment
temperature of 45 degrees Celsius applied to the outside of the
patient's eyelid, as indicated by curve 40. Curve 40 illustrates a
relatively constant 45 degrees Celsius treatment temperature for a
specified treatment time. The temperature at the inner surface of
the patient's eyelid, indicated by curve 41, also increased as a
result when heat was applied to the outside of the eyelid, albeit
with a heat loss drop due to the heat loss from the transfer of
heat from the outside of the eyelid to the eye. If heat is applied
to the inside of the eyelid and to the trabecular meshwork, FIG. 3
illustrates that temperature losses will be reduced and thus
requires either less heat and/or heat application for shorter
periods of time for the heat to be transferred to the trabecular
meshwork.
[0048] The application of heat and force to the trabecular meshwork
is believed to have the effect of loosening or relaxing proteins or
other inhibitors produced by and contained in the trabecular
meshwork that have formed inhibitors and clogged pores. Clogged
pores in the trabecular meshwork can reduce or obstruct secretion
in the outflow pathway of the trabecular meshwork and thus reduce
drainage of aqueous into Schlemm's canal. IOP rises as a result of
blocked or reduced drainage of aqueous through the trabecular
meshwork. By relaxing or loosening the proteins or other inhibitors
in the trabecular meshwork, proper aqueous outflow is restored and
elevated IOP levels as a result of the clogged drainage can
decrease as a result. Loosening or relaxing proteins without
damaging their physical cellular structure in trabecular meshwork
can be performed.
[0049] For example, studies were discovered by the inventors that
indicate the TIGR protein produced and located in the trabecular
meshwork has been predicted to possess characteristics that could
influence the outflow resistance in the trabecular meshwork. (see
Booth et al., TIGR and Stretch in the Trabecular Meshwork,
Investigative Ophthalmology and Visual Science, 40:1888-89, 1999)
Characteristics of the TIGR protein include its oligomerization,
specific binding to the trabecular meshwork cells, and potential
interactions with other extracellular matrix molecules in the
trabecular meshwork. Changes in TIGR protein properties due to
structural mutations and/or its increased expression could be
mechanisms involving outflow obstruction in the trabecular
meshwork. These mutations can be associated with glaucoma. Id.
[0050] In this regard, FIG. 4 is a flowchart illustrating the steps
of a basic embodiment of the present invention for diagnosing and
treating elevated IOP in a patient as a means of either preventing
or halting the effect of glaucoma to retard further vision loss.
The process starts by a physician or certified clinician measuring
the patient's IOP level to determine if IOP is at an elevated or
unsafe level in the patient's eye (step 52). Any technology or
methodology can be used to measure the IOP of the patient's eye.
This includes applanation tonometry, electronic indentation
tonometry, non-contact tonometry (pneumotonometry), and indentation
(Schiotz) tonometry, as well known. Next, the physician or
clinician diagnosing the patient determines if the measured IOP
level is at elevated or at unsafe level and/or if other glaucoma
factors exists, such as reduced blood flow for example (step 54).
It is generally agreed that normal IOP levels for a patient is
between 10 mmHg and 20 mmHg. The average value of IOP has been
observed to be approximately 15.5 mm Hg with fluctuations of about
2.75 mmHg.
[0051] With regard to IOP, IOP levels can vary from patient to
patient and based on a variety of conditions. For example, IOP can
vary throughout the day and night. The diurnal variation for normal
eyes is typically between 3 and 6 mmHg. This variation may increase
for glaucomatous eyes. During the night, IOP usually decreases due
to slower production of aqueous humor. IOP can vary with a number
of other factors, such as heart rate, respiration, exercise, fluid
intake, systemic medication, and topical drugs. Alcohol consumption
can also lead to a transient decrease in intraocular pressure and
caffeine intake may increase IOP. IOP may also become elevated due
to anatomical problems, inflammation of the eye, genetic factors,
as a side-effect from medication, or during exercise. IOP also
usually increases with age. Corneal thickness and rigidity can also
affect what is considered to be a normal IOP for a particular
patient. The thicker the patient's cornea, the higher IOP may be
and still be considered at a normal, safe level. Thus, when
diagnosing the patient, the physician or clinician must take into
account their experience and these wide range of factors to
determine if the patient's IOP is at elevated or unsafe levels such
that treatment should be administered.
[0052] If the patient's IOP level is determined to be at a safe
level and/or other glaucoma factors are such that treatment should
not be administered (decision 56), the process ends (step 57). If
on the other hand, the patient's IOP is determined to be at an
elevated or unsafe level and/or other glaucoma factors exist such
that treatment should be administered (decision 56), treatment
according to the non-invasive treatment process and apparatuses
according to the present invention may be used to lower IOP and
sustainably over other methods. The treatment process in general is
to apply regulated heat and/or force to the patient's trabecular
meshwork in order to loosen or relax protein clogs or other
inhibitors that are reducing or preventing normal outflow of
aqueous humor (step 58). The applied heat can be diffuse and
non-focused to direct heat energy to the trabelcular meshwork via
intervening tissue. For the purposes of this application, to
"loosen" or "relax" proteins or other inhibitors in the trabecular
meshwork means to lessen the rigidity of any inhibitors such that
outflow is increased. By sustainably, it is meant that IOP is
reduced for periods of time, such as up to three months for
example, although the present invention is not limited to any
specific amount of time.
[0053] Any number of methods and devices may be used to apply heat
and/or force to the trabecular meshwork. Examples of these methods
and devices will be described through the remainder of this
application. For example, the heat may be applied to the outside of
the patient's eyelid or inside the patient's eyelid on the eye. As
illustrated in FIG. 3 and previously discussed, the heat transfer
characteristics to the trabecular meshwork will be different
depending on which of these methods of heat transfer is employed.
If heat is applied to the outside of the patient's eyelid, a
greater temperature and/or duration of heat may be required due to
the heat loss across the patient's eyelid. One reason contributing
to heat loss is the intervening tissue of the eyelid between the
heat application device and the patient's eye. Also, it has been
found that blood flow through blood vessels in the patient's eyelid
tends to act as a heat sink carrying heat away from the eye. If
instead, heat is applied to the inside of the patient's eyelid on
the eye, temperature and/or duration may be reduced while still
attaining the same effective heat transfer to the trabecular
meshwork. Regardless of where heat is applied by the heat
application device, the temperature of the heat application device
should be regulated such that the resulting heat that reaches and
is applied to the trabecular meshwork is the desired temperature to
be effective in loosening or relaxing protein clogs or other
inhibitors in the trabecular meshwork.
[0054] It may only be required to increase the temperature at the
trabecular meshwork a few degrees above body temperature (e.g. 40
to 44 degrees Celsius) for a sufficient period of time (e.g., 20
minutes) to loosen or relax protein clogs or other inhibitors in
the trabecular meshwork. The goal is to apply heat sufficient to
loosen or relax protein clogs or other inhibitors, but to not raise
the temperature to a point where the proteins are damaged. Duration
of heat as well as the application of force can interplay with heat
transfer for an effective treatment. For example, a longer duration
of treatment (e.g., 60 minutes) may allow the temperature of heat
application to the patient's eye to be reduced (e.g., 42 degrees
Celsius) while still providing an effective lowering of the
patient's IOP, as opposed to a higher temperature of heat
application (e.g., 47 degrees Celsius) applied for a shorter period
of time (e.g., 45 minutes).
[0055] Further, the application of force may assist the application
of heat to sufficiently loosen or relax protein clogs or other
inhibitors and reduce IOP as a result. For example, a force may be
applied such that a pressure is applied to the trabecular meshwork.
The application may also allow the temperature of the heat
application and/or duration of application to be reduced from what
it would otherwise be, to sufficiently loosen or relax protein
clogs or other inhibitors and reduce IOP as a result. (e.g., 40-45
degrees Celsuis for a duration of thirty (30) to sixty (60)
minutes). The force may also be applied in the form of a vibratory
or massaging force, to assist in the loosening or relaxing of
protein clogs or other inhibitors. The force may also be applied
either simultaneously during heat application, for a portion of
heat application, or subsequent to heat application.
[0056] Turning back to FIG. 4, after the desired amount of heat
and/or force combination has been applied to the patient's eye and
thus the trabecular meshwork and for the desired duration, the heat
and/or force application is removed from the trabecular meshwork
(step 60). The physician or clinician then measures the patient's
IOP level and/or determines if the glaucoma factors remain (step
62). The patient or physician determines if treatment should be
reapplied or not during the same session based on the measured IOP
level and/or analysis of other glaucoma factors (decision 64). The
physician or clinician can check to determine if the patient's IOP
level has lowered. However, the IOP level measured may still not be
lowered to normal or safe levels to ensure the prevention of
glaucoma or to retard its continued effect. If IOP level remains
elevated beyond desired levels and/or other glaucoma factors exist
in an undesired or unsafe manner, the physician or clinician can
reapply treatment by repeating steps 58-62, as discussed above. If
treatment should not continue (decision 64), treatment ends and the
patient is scheduled for a follow-up visit in the future as part of
monitoring the patient's IOP (step 66). It is important to continue
to monitor the patient's IOP level over time to ensure that it
remains lowered. The present invention has been shown to
sustainably lower IOP, but inevitably, IOP levels may rise again
such that periodic and continued treatment should be
administered.
[0057] FIG. 5 illustrates a block diagram of one embodiment of a
heat and force application device 70 that may be employed with the
present invention to apply heat and/or force to the trabecular
meshwork to reduce IOP. In this embodiment, the heat and force
application device 70 applies heat and/or force to the outside of
the patient's eyelid and in a direction towards the trabecular
meshwork, such that heat and pressure is transferred and applied to
the trabecular meshwork. The heat and force application device 70
directs diffuse and non-focused heat energy to the trabecular
meshwork via intervening tissue in this embodiment. This may be
desirable so that heat energy is not directed directly onto the
trabecular meshwork risking damage to same, although the invention
is not limited to diffused, non-focused heat energy. It is noted
that this treatment (as well as the other treatments described and
apparatus described herein) can be utilized or adapted for either
the upper or lower eyelid, or both upper and lower eyelid for
either left or right eye, or both left and right eyes. In this
embodiment, a power supply 72 supplies power to a heat regulating
circuit 74, which may be of any suitable design to provide heat
regulation. This heat regulating circuit 74 applies an electrical
signal such as a current (AC, DC, pulsed, programmed or modulated)
to a heating element 76 (e.g., a flexible foil heater element that
produces heat by virtue of the heat produced when current passes
through a resistor, i.e., resistive heating) in order to produce a
regulated temperature transfer to the trabecular meshwork within
the therapeutic range (e.g. 40-45 degrees Celsius). This heating
element 76 is used to generate the heat which ultimately is
transferred to the trabecular meshwork for heat therapy.
[0058] In the present embodiment, a heat sink 84 is disposed
between the heating element 76 and eyelid 85 of eyeball 22. The
heat sink 84 is show in a cross-section view to illustrate that the
heat sink 84 is preferably in the shape of a ring with a void in
the center. Although not limiting, this is so heat is
preferentially directed to the circumference area of the sclera in
a line towards the trabecular meshwork and outside or out of line
with the pupil and iris of the eye for safety reasons. This may
also enable higher temperatures of heat to be applied to compensate
for any heat transfer losses that may occur. This heat sink 84 may
be either, for example, a flexible silicon member that flexes
(along with the heating element in some embodiments) to conform to
the shape of the eye being treated. In one embodiment, a flexible
silicone rubber pad that is relatively thermally conductive (e.g.,
one or two layers 1/16 inch thick) can be used. Alternatively, the
heat sink 84 may be a rigid or relatively rigid thermally
conductive member, which is pre-shaped to closely conform to the
outer surface of the eyelid 85. In this embodiment, one typical
size or multiple sizes may be provided to match the eyeball contour
and apply heat to both the upper an lower lids simultaneously,
which could then apply heat to the trabecular meshwork through a
single eyelid of a single eye or both eyelids of a single eye, or a
single eyelid of both eyes or both eyelids of both eyes.
[0059] In this embodiment, the heating element 76 is sandwiched
between the heat sink 84 and an insulator 78. Insulator 78 serves
to minimize heat loss from the back side of the heating element 76,
and thereby assists in channeling heat from the heating element 76
through the heat sink 84 to the eyelid 85. In certain embodiments,
a backing plate 82 is optionally applied to the outer surface of
the thermal insulator 78 in order to assist in attaching the
assembly to the eyelid or otherwise contacting and engaging the
eyelid 85, as will become clear later. In certain embodiments, a
slight force, illustrated by arrow 80, urges the heat sink 84 into
close contact with the eyelid 85 in order to more efficiently
transfer thermal energy to the trabecular meshwork while also
applying force to the trabecular meshwork to urge the loosening or
relaxing of protein clogs or other inhibitors in the trabecular
meshwork.
[0060] In accordance with certain embodiments, the heating element
76 is realized as a flexible foil resistive heating element. Such
elements comprise a flex-circuit having resistive pathways through
which electrical current is passed to cause generation of resistive
heat. In such heating elements, the temperature can often be
monitored by measurement of the resistance of the element, which
changes somewhat as the element heats up. Resistance can be
measured in a number of ways including indirectly by measuring the
current flow to the heating element and/or the voltage applied
across it. Hence, in such heating elements as used in this
particular embodiment, the primary or only mode of heat production
is via direct contact of the heating unit with heat provided by
resistive heating and production of potentially harmful infrared
light energy is minimal or non-existent. Additionally, the heating
element 76 may be realized as a collection or array of heating
elements without limitation. Each of these variables and others
will occur to those skilled in the art upon consideration of the
present teachings. Other types of resistive heating elements may
also be used without departing from embodiments consistent with the
present invention.
[0061] The circuit depicted in FIG. 5 is general in nature and may
utilize many variations consistent with embodiments of the present
invention. In one embodiment, a fixed temperature device, such as
that illustrated in FIG. 5, may be utilized in which the heat
regulating circuit 74 is factory calibrated to produce the desired
constant therapeutic temperature at heating element 76. This
constant therapeutic temperature can be factory calibrated by
measurement of the temperature and resistance of the heating
element 76 or heat sink 84 so that a safe and therapeutic level of
heat is obtained. A selection of heat settings can be provided for
use by the clinician or physician. The heat regulating circuit 74
may also incorporate a timer so that heat is applied for a
specified period of time once the heating cycle starts, and the
heat is terminated after the specified treatment time. In addition,
the heat regulating circuit 74 may trigger an alarm notifying the
user of an end of the treatment period when the specified treatment
time has expired. In general, a treatment time of about thirty
minutes has been found to be satisfactory, but a great deal of
variation and optimization may be possible without deviating from
the present invention. Generally, times ranging between about
thirty (30) and sixty (60) minutes are appropriate, depending upon
the severity of protein clogs or other inhibitors in the trabecular
meshwork and temperature, but this should not be considered
limiting.
[0062] For purposes of this document, the insulator 78 is suitably
insulative so as to tend to serve as a barrier to the escape of
heat from the rear of the heating element 76, whereas, the heat
sink 84 should be suitably conductive so as to tend to draw heat
from the heating element 76 toward the eyelid 85. In embodiments
where contact with the human eyelid is desired, it is often
desirable that the heat sink 84 or other element placed in contact
with the eyelid 85 be soft and comfortable. This may limit the
actual absolute thermal conductivity of that material. However, so
long as there is a reasonable tendency for heat to flow through the
material, it will be considered a heat sink. Similarly, the
insulator 78, due to similar restrictions as well as size, is
unlikely to resemble an ideal insulator, but keeping the heat
adequately directed toward the eye 12 with a reduction in heat loss
over the bare heating element 76 is adequate to be considered an
insulator. The relative thermal conductivity of the heat sink 84
can therefore be greater than the thermal conductivity of the
insulator 78, and preferably it should be much greater (e.g., a
factor of 10). That is, the insulator 78 should preferably be less
conductive of heat than the heat sink 84.
[0063] In prototypes, the insulator 78 had thermal conductivity of
approximately 0.10 W/mK (watt per meter-Kelvin), while the heat
sink had a thermal conductivity of approximately 1.3 W/mK. However,
these conductivity values should not be considered limiting. In
certain embodiments, the backing plate 82 may serve adequately to
provide the function of the insulator 78.
[0064] It will be appreciated by those skilled in the art that the
terms "heat sink" and "thermal insulator" are relative terms that
describe the tendency of a material, in any form, to either absorb
and transfer heat or inhibit the flow of heat. For example, the
insulator 78 can also be provided in the form of an air or other
gas pocket.
[0065] For purposes of this document, the term "heat sink" will
suggest that the substance in question is a relatively good
conductor of heat (compared to the insulator utilized). For
materials such as thermally conductive silicon rubber, heat
conductivity is generally better than that which would be
considered a thermal insulator, even though it may not be as good
as a metal such as steel or aluminum. However, commercially
available materials that are designed for enhanced thermal
conductivity are available and are made of flexible material such
as silicon rubber. Similarly, most "thermal insulators" will
inherently conduct a certain amount of heat. This fact will not
preclude a material from being considered a thermal insulator for
purposes of this document. Thermally insulating materials such as
insulating foam rubber and plastics and the like are commercially
available.
[0066] One example of a thermally insulating material suitable for
use in embodiments of the present invention is neoprene rubber with
a thickness of approximately 1/8 to 1/4 inch, but these dimensions
should not be considered limiting. Thermally conductive silicone
rubber materials can be obtained commercially from a number of
sources including, for example, Stockwell Elastomerics, Inc. of
4749 Talbut Street, Philadelphia, Pa. 19136 as product T100.
[0067] The heat and force application device 70 may also include a
separate temperature sensor 86 adjacent to the heating element 76.
This temperature sensor 86 is shown for convenience as occupying a
separate layer in the structure, but this is merely for convenience
of illustration. Temperature sensor 86 could be placed anywhere
between the insulator 78 and the heat sink 84, between the heating
element 76 and the heat sink 84, between the heating element 78 and
the insulator 78, embedded within the heating element 76, embedded
within the heat sink 84, or at the surface of the eyelid 85,
without limitation, so as to read the temperature being generated
by the heating element 76 and/or delivered to the outer surface of
the eyelid 85, which is transferred to the trabecular meshwork. If
the heat sink 84 and insulator 78 properly do their job, any of
these points can be used to measure the temperature that is
ultimately delivered to the outer surface of the eyelid (or can be
calibrated to represent the final eyelid surface temperature) to a
reasonable degree of accuracy (after a settling time period).
[0068] The temperature sensor 86 may be realized as an array of
sensors in certain embodiments. Temperature sensor 86 sends an
electrical signal back to the heat regulating circuit 74 so that
the heat regulating circuit 74 can monitor the actual temperature
generated by heating element 76. Feedback control techniques can
then be utilized so that proper heating within a therapeutic range
is maintained at heating element 76. Temperature sensor 86 may be
realized in a number of ways including, but not limited to, a
thermocouple (e.g., the extremely small thermocouples available
from Physitemp Instruments Inc. of 154 Huron Avenue, Clifton, N.J.
07013) or a conventional miniature thermistor.
[0069] The heat and force application device 70 illustrated in FIG.
5 may also include a vibratory element 88. The vibratory element 84
generates a vibratory force towards the eyelid 85 and to the
trabecular meshwork to aid in the loosening or relaxing of protein
clogs or other inhibitors in the trabecular meshwork, as previously
described. The vibrating element 88 is show in a cross-section view
to illustrate that it is preferably in the shape of a ring with a
void in the center. Although not limiting, this is so vibratory
force is preferentially directed to the circumference area of the
sclera in a line towards the trabecular meshwork and outside or out
of line with the pupil and iris of the eye for safety reasons. The
vibratory element 88 is optional, and may or may not be activated
during heat application by the heating element 76. For example, the
vibratory element 88 may be activated after the heat regulating
circuit 74 is controlled to deactivate heating, such that the heat
and vibratory force are applied to the trabecular meshwork at
different times.
[0070] FIG. 6 illustrates a block diagram of the heat and force
application device 70 components consistent with FIG. 5 to further
illustrate this embodiment. A heater unit 96 incorporates (in
addition to a thermal heat sink 84, insulator 78, backing plate 82,
etc.) heating element 76, along with a separate or integral
temperature sensor 86 and the vibratory element 88, which all form
a part of the heater unit 96, which is placed in contact with the
eyelid. In this embodiment, a control processor 92 uses a
temperature regulator circuit 90 (such as those previously
described or other design) to form the heat regulating circuit 74.
Power supply 72 supplies power both to the heating element 76 and
the control processor 92, as well as being able to supply power to
the vibrating element 88 and an optional alarm 98. In this
embodiment, a user interface 94 (e.g., which may incorporate
display) may be supplied, in which the user may interact with the
control processor 92 in order to control various aspects of the
operation of the device 70. In one embodiment, for example, the
user interface 94 may be utilized to adjust the treatment time,
temperature, and application of force, including control of the
vibratory element 88. Elements of this and other embodiments may be
freely interchanged without departing from the invention.
[0071] For purposes of this document, it is useful to define
vibratory energy as mechanical motion having a frequency component
and an amplitude component. It is currently believed to be most
desirable that the frequency component be between approximately 0.1
Hz and 300 Hz and include random oscillations, and that the
amplitude component be defined as the amount of displacement in the
direction of the trabecular meshwork 22, which is preferably up to
about 3 mm, with a currently preferred deflection being about 0.5
mm. However, this should not be considered limiting since
optimization of these parameters and definition of a suitable
profile may be optimized by experimentation. In one embodiment, for
example, the temperature profile might be to establish a constant
temperature of 45 degrees Celsuis for thirty (30) minutes with
application of linearly increasing vibratory energy from 0.1 Hz to
300 Hz and over the last five (5) minutes the amplitude of the
vibratory energy decreasing from 3 mm to 0 mm linearly. The actual
profiles used can be optimized experimentally after considerations
of the teachings provided herein.
[0072] As noted earlier, the heating profile of the heating element
76 used in prototypes produced a temperature gradient of several
degrees Celsius across the eyelid. Prototypes utilized Minco
Thermofoil Heater HK5207R6.5L12A. While quite functional, this
heating element 76 did not have an ideal temperature profile and
thus only heated a portion of the eyelid.
[0073] FIGS. 7 and 8 illustrate further embodiments for controlling
the application of heat that may be employed in the heat regulating
circuit 74 illustrated in FIGS. 5 and 6. In the embodiment of FIG.
7, the heat regulating circuit 74 is implemented by use of the
control processor 92, which received feedback information from
temperature sensor 86 and utilizes this information to control a
temperature regulator circuit in the form of a switch 90' that
applies power to the heating element 76 in order to regulate the
temperature of the heating element 76. While this embodiment
depicts the heating element 76 and temperature sensor 86 as being
two separate devices, as previously indicated, the resistance of
the heating element 76 or other characteristics of the heating
element 76 can also be utilized for purposes of sensing the
operational temperature of the heating element(s). Control
processor 92 operates using an internal or external clock (not
shown) so that it may further provide control of the amount of time
in which the heating element 76 is activated and may provide an
alarm in the event of a malfunction or in the event of the end of
the specified treatment periods. Other functions may also be
carried out with control processor 92 without departing from the
present invention.
[0074] FIG. 8 depicts a further embodiment of a mechanism for
regulating the temperature of the heating element 76. In this
embodiment, the control processor 92 similarly controls the
operation of the heating element 76 based upon temperature sensed
by either a separate temperature sensor 86, or by the heating
element 76 itself. This information is used to control a heat
regulating circuit in the form of a pulse width modulator 90''. By
increasing the width of the pulses produced by pulse width
modulator 90'' (i.e., increasing the duty cycle), the heating
element 76 will produce more heat, and reducing the width of pulses
produced by pulse width modulator 90'' will reduce the temperature
of heat generated by heating element 76. Other modulation schemes,
including but not limited to a variable voltage and/or variable
current source may also be utilized to regulate the heating of the
heating element 76 without departing from the present invention.
Again, control processor 92 may also control other functions, as
will be discussed later.
[0075] FIG. 9 illustrates one embodiment of the heat and force
application device 70, consistent with embodiments of the present
invention is depicted in which a separate housing 99 is used to
house the power supply 72 and the temperature regulating circuit
90. This housing 99 can be attached by wiring 100 to the heater
unit 96 and by wiring 101 to the vibratory element 88, if present.
Alternatively, the power supply 72 and the heat regulating circuit
74 can be embedded within the goggle assembly or a helmet-like
assembly. Heater unit 96 incorporates some or all of the elements
described in FIGS. 5 and 6 (as well as variations described later)
with the outer surface of the heat sink 84 providing an interface
to the eyelid 85. Heater unit 96 could incorporate the heat sink
84, the heating element 76, possibly temperature sensor 86, as well
as insulator 78 and backing plate 82. One or two layers of a 1/16
inch thick silicon rubber heat sink can be used. The backing plate
82 in the present embodiment is utilized to affix a ball 104 to a
captivating socket in the backing plate 82 so that the heater unit
96 can be rotated and otherwise adjusted with respect to a holder
(e.g., goggles as will be described) to appropriately contact the
eyelid 85 to transfer heat to the trabecular meshwork. The ball 104
is in turn connected to a threaded shaft 106 which has a wing nut,
thumbscrew, or other conveniently manipulated termination 108 so
that the user, clinician, nurse, physician or clinician can screw
the shaft 106 in to adjust the contact with the eyelid 85 and
thereby adjust the initial pressure placed on the eyelid 85 by the
heater unit 96. In this embodiment, the shaft 106 is screwed
through a lenspiece 112 forming a part of a goggle 110 which the
user straps to the patient's head using adjustable straps 114 in a
more or less conventional manner.
[0076] In certain embodiments, the heat sink 84, or the entire
heater unit 96 or portions thereof may be made disposable so that
the regulator and other parts may be re-used with multiple
patients, while remaining sanitary.
[0077] For purposes of this document, goggles 110 are used as an
illustrative embodiment of a holder or interfacing mechanism that
keeps the heater unit 96 in place, but other mechanisms are also
possible. Thus, the use of the term "goggle" for descriptive
purposes shall be considered to be any type of goggle, frame,
headgear, goggle-like headgear, helmet, strap, or other device that
fits on a patient's head in any manner and can be utilized to hold
a heater unit, such as 96, in contact with a patient's eyelid 85
during treatment, as described herein. A goggle's lenspiece 112 as
discussed is defined as an element of the goggle 110 or other
device that is situated approximately where a lens would normally
reside in front of the eye 12, and does not necessarily imply the
presence of an actual optical lens.
[0078] In this embodiment, goggles similar to those used for
swimming can be adapted to carry the heater unit 96 and hold it in
proximity to the eyelid 85 being treated during the specified
treatment time. While the goggles 110 illustrated in FIG. 9 are
more or less conventional goggles, such as those used for covering
the eyes during swimming, any other suitable mechanism for holding
the heater unit 96 in place at one or more of the eyelids to be
treated can be utilized, including adhesives, tapes, straps,
helmets, clamps or any other suitable expedient. Each such
mechanism can be considered a suitable interfacing mechanism for
purposes of this document.
[0079] FIG. 10 illustrates a further embodiment of a heat and force
application device 70 depicted. An exemplary vibrating element 88
is incorporated within the apparatus. In this embodiment, a generic
vibrator 88 is depicted as embedded within an eyepiece 102.
Further, the eyepiece 102 is preferentially shaped in the form of a
ring 103 with a void 105 in the center so heat and force are
preferentially directed to the circumference area of the sclera in
a line towards the trabecular meshwork and outside or out of line
with the pupil and iris. However, this embodiment could include a
solid eyepiece 102 as well, if temperature and force are monitored
and controlled such that any heat or force reaching the iris or
pupil does not inflict damage. Such vibrating element 88 can be of
any suitable design. There are multiple mechanisms that can be
utilized to provide vibratory energy to the heated eyepiece 102.
Examples, which should not be considered limiting, are as
follows:
[0080] First, an offset motor can be used and attached to the outer
surface of the eyepiece heater unit 96 or shaft 106. Some such
offset motors operate by having an eccentric weight attached to the
shaft that causes vibration when the motor is powered. An offset
motor is used in cellular telephones and beepers to alert the user.
They are readily commercially available in different sizes and can
operate to produce vibrations at various different frequencies and
amplitudes. An appropriate frequency and amplitude can be
determined by experimentation upon consideration of this
teaching.
[0081] Button type vibration motors can be embedded within the
eyepiece 102 or otherwise attached in a manner operative to induce
vibration. A small motor can also be placed on the threaded shaft
106 which attaches to the goggle/mask 110 and heater unit 96. The
motor can then be used to rotate a figure eight screw causing it to
move in and out. The amount of displacement in this case is fixed
but the speed (frequency) can be controlled with a micro-processor
unit. Further, a small piezoelectric motor can be used to move the
threaded shaft 106 which attaches to the goggle 110 and heater unit
96. The amount of displacement and frequency of operation can be
controlled with a microprocessor unit.
[0082] The threaded shaft 106 between the lenspiece 112 and the
heater unit 96 can be removed and replaced with a diaphragm. The
diaphragm can be placed between the goggles 110 and the heater unit
96, attached to both. A simple pulsating gas (e.g., air) or fluid
pump can be used to inflate and deflate the diaphragm thus
providing mechanical motion to the heater unit 96. The amount of
gas or fluid and frequency of pulses can be controlled by a
microprocessor unit.
[0083] Other embodiments wherein mechanical energy, where
mechanical energy is defined as any form of mechanical pressure on
the trabecular meshwork to assist in loosening or relaxing protein
clogs or other inhibitors is applied using any suitable mechanism
can be devised upon consideration of the present teachings. Once
the heating element 76 has served to loosen or relax protein clogs
or other inhibitors in the trabecular meshwork, application of
mechanical energy such as pulsing, vibratory energy, milking, etc.
action to the eyelid can further assist in stimulating the protein
clogs or other inhibitors to assist in loosening or relaxing
protein clogs or other inhibitors in the trabecular meshwork to
restore the flow path for aqueous humor.
[0084] FIG. 11 depicts one example of a heating unit 96' employing
a heating element 76' that is customized for heating the eyelid 85
and transferring heat to the trabecular meshwork. Such heater
element design 76' can be fabricated by foil heater companies such
as Minco of 7300 Commerce Lane, Minneapolis, Minn., 55432. In this
embodiment, the outside profile of the heater element is designed
to fit the contour of the lower eyelid 85, but other designs can be
devised to treat the upper eyelid or both eyelids 85
simultaneously. One typical set of working dimensions for such a
heater design is approximately 1.8 inches for dimension 124
approximately 1.015 inches for dimension 126 and approximately
0.375 inches for the tab 120 at dimensions 128 and 130. Of course,
these dimensions should not be considered limiting, but are
believed to be suitable for an average sized human eyelid. This
design provides tab 120 that is bent back at about 90 degrees away
from the eyelid 85 and provides for attachment of wires 118.
Additionally, tab 120 and the shape of the foil heater reduces the
unevenness of heating across the eyelid noted in standard
commercial foil heaters that were tested.
[0085] In accordance with certain embodiments, a heater unit 96''
(e.g. as in FIG. 12) may be attached with wires 118 coupled to the
heating element 76'' and a plug connection to the temperature
regulator circuit 90, so that the heater unit 96'' may be detached
for cleaning, or for disposal of a portion of (e.g., the heat
sink), or the entire heater unit 96. In this manner, sanitation can
be maintained while portions of the apparatus can be reused, and
speed of treatment enhanced.
[0086] The heating is resistive heating produced by the resistance
of the conductive path between the conductors that terminate at tab
120. In this embodiment, the heating path meanders left to right
and right to left to provide the resistive path producing the heat.
In other embodiments, the resistive path can meander up and down
and down and up to produce the resistive path as depicted in FIG.
12. Many other patterns can also be used. The dimensions and
precise layout of the paths are designed to maintain distance
between conductors, line width and resistance appropriate to
generate the required heat with an even heating profile, utilizing
conventional design principles for foil heater or other resistive
heater designs. Moreover, other heating technologies other than
foil heaters and other than resistive heating can be used without
departing from the present invention.
[0087] Those skilled in the art will appreciate upon consideration
of the present teachings that many variations in the embodiments
depicted are possible without departing from the present invention.
For example, the heating element 76 should preferably provide heat
to the eyelid 85 that is directed to the trabecular meshwork 22
preferably without being directly directed to the iris or pupil,
and this may be accomplished using an array of heating elements
rather than a single heating element. The heating element 76 is
preferably a flexible heating element, such as a foil heating
element, to assist with conforming to the shape of the eyelid 85.
However, the heating element 76 may also be rigid and provided in
preformed shapes to conform with one average or a variety of eyelid
shapes and sizes. Alternatively, a rigid heating element 76 may be
accompanied by a soft heat sink 84 which would conform to the
eyelid 85. As discussed earlier, this heat sink 84 can be made of a
thermally conductive rubber, a fluid, gel or gas filled diaphragm,
a damp cloth, or any number of materials which would be thermally
conductive and readily conformable.
[0088] The heat sink 84 may be made of thermally conductive rubber
or silicon or can be an encapsulated fluid or gelatin. In other
embodiments, the heat sink 84 can be a solid thermally conductive
material which is appropriately shaped to conform to the eyelid
geometry (i.e., conform to a surface that is approximately a
section of an oblique spheroid). The insulator 78 can be made from
a nonconductive rubber or foam material (where nonconductive is
intended to mean low thermal conductivity) or may be made from a
low thermal conductivity solid material. The heating element 76 may
be used in conjunction with a thermal conductive gel, liquid, or
cream to fill gaps between the heat sink 84 and eyelid 85 in order
to provide a more uniform conductive boundary between the eyelid 85
and the heater unit 96. Alternatively, sweat produced from heating
the lids inherently assists in increasing heat transfer and is a
byproduct of using a nonabsorbent heat sink like thermally
conductive silicon rubber. The layers depicted can be integrated
together in any suitable manner and may take any other form
suitable to the end purpose of providing relatively uniform
regulated heating of the eyelid.
[0089] The temperature regulating circuit 90, which regulates
temperature of the heating element 76, and if present the vibratory
element 88, may be operated under computer control and may have
temperature set points and vibratory set points including amplitude
and frequency that are adjustable by the user. Additionally, if
desirable, a variety of temperature profiles and/or mechanical
energy profiles can be implemented under computer control where the
temperature and vibratory energy can be ramped up and/or down over
time if this is deemed to be a desirable control feature. The
temperature regulator 90 and/or mechanical energy element can also
operate on a timer to limit the time limit of the treatment. While
pulse width modulation and simple on/off switching have been
disclosed for regulating the temperature of the heating element,
other embodiments will occur to those skilled in the art upon
consideration of the present teaching. In accordance with certain
embodiments, this heat regulation and/or mechanical energy
regulation may be carried out under control of a computer, such as
a microprocessor operating under control of a computer program
stored as instructions in an electronic computer readable storage
medium, such as a read only memory (ROM) or other suitable storage
medium.
[0090] The power supply 72 may utilize batteries which may be
replaceable or rechargeable, or the power source may utilize AC
power which may be converted to DC as needed for implementation of
the device.
[0091] Any suitable mechanism can be utilized for attaching the
heater unit 96 to the eyelid 85. As disclosed above, this can be
done with double sided medical tape or with a head piece, such as
goggles 110, to hold the heater unit 96 in place. In other
embodiments, the heater unit 96 may be strapped in place, held in
place by the bridge of the nose, swiveled into place, screwed into
place by means of a goggle mechanism, latched into placed, or
utilizing any other suitable adjustment mechanism from goggles or
other head gear. Such mechanism serves to adjust the amount of
force placed on the eyelid from the heater unit 96. In other
embodiments, a mechanism may also be devised which automatically
adjusts the force placed on the eyelid 85, and the mechanism may be
included either within the heater unit 96 or otherwise coupled to
the heater unit 96 (for example, in the goggles 110) to transmit
mechanical energy to the heater unit 96.
[0092] With reference to FIG. 13, one can envision any number of
treatment regimens that can be carried out using the various
embodiments disclosed. This flow chart depicts the general process
one would go through to carry out a treatment in accordance with
certain embodiments, and to perform step 58 in FIG. 4, for example.
First, the heater unit 96 is installed onto the patient (e.g.,
using the goggle 110 arrangement or adhesive arrangements depicted)
(step 142). In those embodiments in which force can be applied, the
pressure is adjusted to urge the heater unit 96 into contact with
the eye 12 or eyelids 85 to be treated with a selected measure of
gentle force. The heater unit 96 can then be turned on and the
treatment cycle begins according to a manual or automated process
(step 144).
[0093] Once the heater unit 96 reaches an appropriate treatment
temperature (e.g., 45 degrees Celsius), feedback control is
utilized to maintain the heat at a constant level or to achieve a
desired heat treatment profile (step 146). Similarly, at a desired
timing of the treatment profile, mechanical energy can be added (if
the embodiment of the heater unit 96 is so equipped) (step 148). It
currently appears that best results can be achieved when mechanical
energy is applied when the therapeutic temperature is reached and
discontinued shortly after the heat therapy is completed. This
process proceeds according to the selected treatment profile
(either selected by an operator or pre-programmed) until the
treatment profile is complete (decision 150). The treatment then
either ends or additional treatment is resumed (step 152).
[0094] Thus, a method of treating at least one of a patient's
eyelids with a regulated heat in a manner consistent with certain
embodiments involves: placing a heating unit 96 having a heating
element 76 in contact with the patient's eyelid to transfer heat to
the trabecular meshwork; and applying a control signal to the
heating element 76 to generate heat at the heating element 76 and
transfer the generated heat to the trabecular meshwork for a
prescribed time period.
[0095] Referring now to FIG. 14, a heating unit 96 consistent with
certain embodiments is depicted in which again a layered sandwich
style assembly is depicted with an insulator 78 providing a
rearmost layer, the heating element 76 providing a central layer,
and the thermal heat sink 84 providing a front layer, which will be
placed in contact with the eyelid 85. The heating unit 96 is also a
diffuse and non-focused heat source. In this embodiment, an
adhesive 160 is applied to the outer surface of the heat sink 84 in
order to affix the heater unit 96 to the eyelid 85. In this
example, the adhesive 160 may be in the form of a double-sided
adhesive tape, which has a cover that is peeled off to reveal the
adhesive in order to affix the heater unit 96 to the eyelid 85. In
the example depicted, the thermal heat sink 84 may be flexible or
pliable so that when pressed in place it conforms to the shape of
the eyelid 85 to provide close contact between the thermal heat
sink 84 and the eyelid 85. However, in other embodiments, the
surface carrying the adhesive 160 may be shaped in a manner that
conforms with the up and down, as well as top left and right
curvature of the eyelid to be treated. In this example, thermal
heat sink 84 can be rigid rather than pliable. A somewhat half-moon
shape is depicted for ease of illustration, but the shape is
preferably one which closely conforms to the shape of an eyelid or
pair or eyelids 85. In particular, since the lower eyelid is
generally most problematic, a suitable shape to conform to the
lower eyelid 85 is desirable.
[0096] When using any adhesive mechanism to attach the heater unit
96, it is desirable to clean and dry the surfaces to which the
adhesive is applied in order to remove all body oils and the like
to assure that the adhesive will firm affix to the eyelid 85
properly. Failure to do so may result in separation of the heater
unit near the edges rather than conforming with the eyes.
[0097] A similar embodiment to FIG. 14 is depicted in FIG. 15. In
this embodiment, a temperature sensor 86 is embedded in a layer
prior to or forming a part of the thermal heat sink 84. While
depicted as a layer 80, the temperature sensor may be a single
element temperature sensor or may be an array of temperature
sensors, which detects temperature across the various segments or
regions of the heating element 76. Additionally, while a single
foil heating element 76 has been discussed heretofore, the heating
element 76 may be realized as an array of heating elements which
may be individually controlled in order to provide uniform heating
to the point on the eyelid 85 where heat is directed to transfer
heat to the trabecular meshwork.
[0098] FIG. 16 depicts another embodiment consistent with
embodiments of the present invention in which is a heater unit,
such as any of those described heretofore 96, can be attached to
the eyelid by use of a strip of adhesive tape, such as a single
side adhesive medical adhesive tape 162, in order to hold the
heater unit 96 in contact with the eyelid for treatment. Again, the
heater unit 96 is depicted as having a relatively flat but flexible
contact surface which conforms to the shape of the eyelid 85 being
treated in the example illustrated. However, an eyelid conformal
shape using a more rigid heat sink 84 may also be utilized without
departing from embodiments consistent with the present
invention.
[0099] Embodiments of the heat and force application device 70 can
also be executed using a variety of other energy transfer devices,
such as pumpable mediums, including for gases (i.e., air), other
fluids or liquids (glycerin, oils, and the like), and creams. One
such alternative heat and force application device 70' is
illustrated in FIG. 17. As illustrated in FIGS. 17-22, the heat and
force application device 70' comprises a means for applying a jet
of a heated fluid to the exterior surface of the eyelid 85 towards
the trabecular meshwork. The means comprises broadly a pump 170,
goggles 180, and means for delivering a fluid jet to the patient's
eyelid to transfer heat and force to the trabecular meshwork.
[0100] As illustrated in FIG. 17, the apparatus 70' comprises a
pump 170, which may be either AC (wall plug) or DC (battery)
powered (not shown). The pump 170 can be between 1/32 hp and 1/8
hp, with 1/16 hp being preferred based upon currently available
data. One such pump is model STQP with pump head Q3CKC manufactured
by Fluid Metering, Inc. of Syosset, N.Y. The pump 170 has
respective fluid inlet and outlet ports 172, 174. Attached to the
respective inlet and outlet ports 172, 174 is a conduit such as
Polyesters tubing which connects to a goggle-type mask generally
indicated at 180. Further, the pump 170 may be equipped with a
heater (not shown) that heats the medium to the desired
temperature. It will be noted that the preferred temperature of 40
degrees Celsius to 47 degrees Celsius is not the fluid temperature
at the pump exit, but rather is the temperature of the fluid at the
exit of a fluid delivery means 186. Thus, should the heater be
located proximate the pump 170, the temperature may have to be
higher in order to account for a temperature drop as the fluid
travels to the goggles 180. Alternatively, the heater may be
positioned on the tubing proximate the fluid inlet of goggles or
mask 180 where the temperature drop would be minimal. Depending
upon the type of heated medium employed and the location of the
heater itself, heat may be supplied by means of conduction,
convection, or radiation, as appropriate.
[0101] Mask 180 includes a headband 182, which is connected to the
outer edges of mask eyepieces 184. Headband 182 should be
fabricated from a flexible material such as rubber, but should
maintain the eyepieces 184 firmly in place against the orbit and
cheek areas surrounding the eye. The respective eyepieces 184 are
substantially identical in structure and function and for ease of
description reference will be made to "an eyepiece" or a component
thereof. Turning to FIGS. 18 and 19, the eyepiece 184 comprises an
oval annulus or ring 188 of a flexible material such as rubber,
plastic or neoprene of a size sufficient to cover the orbit of the
eye and the eyelids and to create a seal there around. Again,
although not limiting, this ring design may be preferential so that
heat and/or force is directed to the circumference area of the
sclera in a line towards the trabecular meshwork and outside or out
of line with the pupil and iris of the eye. The respective
eyepieces are connected together with a nose piece or bridge 190,
which in the preferred embodiment is integrally molded with the
eyepieces 184. Similarly, the nose bridge 190 may be a separately
attached component, such as in conventional swim goggles. One side
of the ring 188 is adapted to lie flush with the skin of the user
and the opposite side is adapted to mount a lens 192 via
conventional means (such as adhesive bonding or overmolding) to
form a water tight seal. The techniques for lens mounting are well
known to those skilled in the art. The lens 192 is integrally
molded as a single clear unit and has a bottom wall 200, side walls
202, top wall 194, and front wall 208 which together define a
cavity. Drain opening 204 is molded into the bottom wall 200 and
front wall 208 has a slit opening 206 which mounts the means for
delivering a jet of a heated medium or jet means 186, as described
in greater detail herein below.
[0102] Turning to FIGS. 20 and 21, the jet means or rotary
distributor valve 186 comprises a cylindrical manifold 214 having a
bore (not shown) extending along its length. A spiral pattern of
jet orifices 212 are positioned along a portion of the length of
manifold 214 and each of respective orifices 212 is in fluid
communication with the bore. The manifold 214 may also be equipped
with a "neutral" position in which no fluid is permitted to exit
the orifices 212. At one end of manifold 214 is an integrally
molded gear 216 and a nipple 210 at each end. The manifold 214 is
mounted for rotation between the nipples 210. One nipple 210 serves
as the fluid inlet and the other serves as the fluid outlet. A
housing 218 having a bore surrounds the manifold 214, which is
snugly mounted for rotation therein. The housing 218 has a
longitudinal slit 220, which allows fluid from the respective jet
orifices 212 to pass there through such that upon rotation of the
manifold, 214 the jet orifices 212 are sequentially exposed to the
slit 220 and fluid is directed at the eyelid 85. A small electric
or water driven motor 222 is attached to the goggles 180 such that
the drive shaft thereof rotates gear 216.
[0103] In another aspect of the invention, a thin flexible membrane
188 (shown in one eyepiece in FIG. 19, such as a plastic membrane
(not shown) can be located within the goggle cavity and positioned
such that when in place on the eye 12 of the patient, the membrane
is substantially in contact with and covers the eyelid 85. The
membrane operates to define a closed chamber into which the fluid
jet is directed and which strikes the membrane. The force of the
fluid jet is then transmitted through the intervening membrane and
the eyelid into the trabecular meshwork to assist in loosening or
relaxing protein clogs or other inhibitors to reduce IOP.
[0104] In operation, the physician or clinician would position the
device, i.e., the goggles 180 over their eyes with the headband 182
extending around the head to hold the goggles 182 in place such
that when the jet of the heated medium is delivered, it is applied
to the exterior surface of the eyelid 85, proximate the trabecular
meshwork to be treated. As previously mentioned, the goggles 180
should be firmly, but comfortably in place so as to not to move
upon actuation of the apparatus. Alternatively, the device may be
manually held in place against the patient's head. Upon activation
of the pump 170, the heated fluid begins to move through the
conduits 172, 174. During the initial start up period of the
apparatus, the fluid is circulated by pump 170 and is heated to the
required temperature. Once the preferred operating temperature has
been reached, the motor 222 is activated and gear 216 begins to
rotate, which in turn rotates the manifold 214. As the manifold 214
rotates, the jets 212 line up sequentially with the slit 220 and
the fluid jet is directed to the exterior surface of the eyelid.
Further, the fluid jet may also be pulsatory in nature wherein the
fluid jet is intermittent. This intermittency may help to disclose
some of the proteins in the trabecular meshwork 22. Other pulsatory
configurations are also possible. As the manifold 214 rotates, a
continuous side to side scan of the eyelid 85 with warm water jets
and by allowing only one jet on each eye to be active at any
instant in time, effective massage pressure is maximized, while
discomfort is minimized. After the fluid has impacted the eyelid,
it is collected in drain opening 204 and is drained out of the
system loop.
[0105] It is believed that jet pulse frequencies of less than 300
Hz are effective. Depending upon the composition of the protein
clog or other inhibitors, repeated application of the heated fluid
to the trabecular meshwork may be required. The jet of the heated
medium should be maintained for sufficient time to loosen or relax
protein clogs or other inhibitors in the trabecular meshwork to
restore the aqueous humor flow path to reduce IOP.
[0106] FIG. 22 is a flowchart illustrating the steps of an
alternate embodiment of the present invention for diagnosing and
treating elevated IOP in a patient as a means of either preventing
or halting the effect of glaucoma to retard further vision loss. In
this embodiment, regulated heat is applied to the trabecular
meshwork initially without any force (other than may be caused
inherently by application of a heat application device) to apply
pressure to the trabecular meshwork. Instead, heat is applied, and
force is applied subsequently, either manually or with a force
generating device.
[0107] The process starts by a physician or certified clinician
measuring the patient's IOP level to determine if an elevated or
unsafe IOP exist in the patient's eye (step 232). As previously
discussed with respect to FIG. 4, any technology or methodology can
be used to measure IOP of a patient's eye. Next, the physician or
clinician diagnoses the patient to determine if the measured IOP
level is at an elevated or unsafe levels and/or other glaucoma
factors exists (step 234) as previously discussed in FIG. 4.
[0108] If the patient's IOP level is determined to be at a safe
level and/or other glaucoma factors exist such that treatment
should not be administered (decision 236), the process ends (step
237). If, on the other hand, the patient's IOP is determined to be
at an elevated or unsafe level and/or other glaucoma factors are to
the satisfaction of the attending physician or technician such that
treatment should be administered (decision 236), treatment
according to the non-invasive treatment process and apparatuses may
be used to lower IOP. In this embodiment, the treatment process
applies a regulated heat to the patient's trabecular meshwork in
order to loosen or relax protein clogs or other inhibitors that are
reducing or preventing normal outflow of aqueous humor (step 238).
Any number of methods and devices may be used to apply heat to the
trabecular meshwork as previously discussed and as will be
discussed throughout this application. The temperature of the heat
and duration of application may be applied as previously
discussed.
[0109] After the desired amount of heat has been applied to the
trabecular meshwork and for the desired duration, the heat
application is removed from the trabecular meshwork (step 240).
Thereafter, a manual application of force is applied to the eye to
apply pressure to the trabecular meshwork to assist in the
loosening or relaxing protein clogs or other inhibitors and
reduction IOP as a result. For example, a cyclical force may be
applied such that a pressure of 5 psi is applied to the trabecular
meshwork. The application may also allow the temperature of the
heat application and/or duration of application to be reduced from
what it would otherwise be, to sufficiently loosen or relax protein
clogs or other inhibitors and reduce IOP as a result. (e.g., 48
degrees Celsius temperature, at pressure of 3 psi, for duration of
30 minutes). The force may also be applied in the form of a
vibratory or massaging force, to assist in the loosening or
relaxing of protein clogs or other inhibitors.
[0110] The physician or clinician then measures the patient's IOP
level and/or determines if glaucoma factors still exist that are
unsatisfactory (step 244). The patient or physician determines if
treatment should be reapplied or not during the same session based
on the measured IOP level and/or these glaucoma factors (decision
246). The physician or clinician will check to see if the patient's
IOP level has lowered. However, the IOP level measured still may
not be low enough to be at safe levels to prevent the developed
glaucoma or to retard its continued effect. If IOP level remains
elevated beyond desired levels and/or other glaucoma factors are
not to the satisfaction of the physician or clinician, the
physician or clinician can reapply treatment by repeating steps
238-244, as discussed above. If treatment should not continue
(decision 246), treatment ends and the patient is scheduled for a
follow-up visit in the future as part of monitoring the patient's
IOP (step 248). It is important to continue to monitor the
patient's IOP level over time to ensure that it remains lowered
and/or to monitor other glaucoma factors in the patient. The
present invention has been shown to sustainably lower IOP, but
inevitably, IOP levels may rise again such that periodic and
continued treatment should be administered.
[0111] FIG. 23 illustrates a block diagram of a heat application
device 251 components that may be used in this embodiment. The
block diagram is similar to the block diagram of FIG. 2, but the
vibratory element 88 is not present, since a massaging force, if
applied, is applied manually after the heat application device 251
is removed. All of the discussion regarding the heat generation and
control aspects of the heat and force application device 70
illustrated in FIGS. 5-12 and discussed above is equally applicable
to this heat application device 251 and thus will not be
repeated.
[0112] Not only can heat be applied to the outside of the eyelid to
transfer heat to the trabecular meshwork, but heat can also be
applied to the inside of the eyelid on to the patient's eye globe
to transfer heat to the trabecular meshwork. As discussed in
co-pending application Ser. No. 12/015,558, it was previously
unknown to apply heat to the inside of the eyelid and proximate the
eye globe for other treatments not relating to glaucoma. Medical
professionals would have thought it counterintuitive to apply heat
to the sclera. It was thought that applying heat to the sclera
would risk damage to the eyelid or the eyeball itself. Previous
studies of heat application to skin showed that damage could occur
for temperatures at or above 45 degrees Celsius. These studies were
conducted on external keratinized skin. The tissue on the inner
eyelids is non-keratinized epithelium, and as such, is not as well
protected from heat as keratinized skin. Thus, one would naturally
believe that applying heat to the inside of the eyelid would
produce a pain response at lower temperatures than on the outer
eyelid surface. However, it has been surprisingly discovered that
applying heat to the inside of the eyelid and the eye globe is safe
if the heat is regulated, and if preferentially, the heat is
applied outside the iris and pupil.
[0113] Applying heat to the eye globe outside the iris and pupil
and proximate the trabecular meshwork may provide a more efficient
conductive heat transfer to the trabecular meshwork. Attaining a
more efficient heat transfer may allow higher temperatures to be
attained at the trabecular meshwork and/or in a more efficient time
to loosen or relax protein clogs. For example, it was determined
that most patients can tolerate a surface temperature of 43-44.5
degrees Celsius without anesthesia and without significant pain. It
was found that some patients could tolerate temperatures over 44.5
degrees Celsius without anesthesia.
[0114] In this regard, FIG. 24 illustrates an embodiment of a heat
application device 270 that is adapted to apply heat directly to
the eye globe as opposed to the patient's outer eyelid for treating
elevated IOP levels. Preferably, the heating element, which will be
discussed below, is designed to direct heat outside of the
proximity of the patient's iris and pupil and to the sclera
proximate the trabecular meshwork to direct the heat transfer
primarily to the trabecular meshwork. In this embodiment, a heat
application device 270 consists of a hand-held, battery-operated
controller 272 that contains heat generating and regulation
components. The controller 272 can also be a non hand-held device
that is either mounted or rests on a table top, for example. The
controller 272, as described herein, is intended to describe and
encompass any device, including but not limited to electronic and
pneumatic controls and supporting components, that is adapted to
allow and control the application of heat to the patient's eye
globe proximate the trabecular meshwork. The controller 272 is
connected to a disposable component 274 to generate heat on the eye
globe proximate the trabecular meshwork, as illustrated in FIG. 9.
The disposable component 274 consists of a lid warmer 290 provided
in the form of a lens (illustrated in FIGS. 25-27) that applies
heat to the eye globe. The interface 76 wiring can be wrapped
around the patient's ear 277 with any excess clipped to the
patient's clothing.
[0115] The controller 272 may contain a user interface 280 to allow
a physician or clinician to control the heat application device
270. Temperature being applied to the patient's eye globe can be
seen on a temperature display 282. By observing temperature display
282, the physician can determine when a therapeutic temperature has
been reached. For example, the temperature display 282 may be
segment bar graph so that temperature level and the increasing or
decreasing nature of the temperature level can be seen. The
temperature level to be reached at the patient's eyelid can either
be set to a static level within the controller 272, or controllable
by a physician or clinician. A timer display 288 can be provided on
the controller 272 to display the amount of time that heat has been
applied to the patient's eye globe. The timer display 288 can
display a cumulative amount of time passed or provide a countdown
timer if an initial duration is set. For example, the timer display
288 may be comprised of a number of seven segment displays.
[0116] FIG. 25 illustrates the disposable component 274 in more
detail. The disposable component 274 consists of a lid warmer 290
that includes a lens in the disclosed embodiment. The lens 290
contains a heating element (illustrated in FIG. 27) to apply heat
to a patient's eye globe. Preferably, the heating element is
positioned in the lens 290 such that when the lens 290 is
installed, the heating element is outside of the proximity of the
patient's iris and pupil to direct heat transfer to the trabecular
meshwork and away from the iris and pupil. An insulator (shown in
FIG. 27) may be included to insulate the heating element from
inside of the patient's eyelid. As illustrated in FIG. 26, the lens
290 is placed on the patient's eye globe with the patient's upper
and lower eyelids 291A, 291B resting on the outside surface of the
lens 290. Before installation, the scleral side of lens 290 may be
lubricated with saline, or equivalent lubricating drops. The lens
290 is then inserted onto the patient's eye under the eyelids 291A,
291B. The heating element 306 (illustrated in FIG. 27) is contained
within the lens 290 that can apply heat to the patient's eye globe
to be transferred to the trabecular meshwork when installed. The
material used to construct the lens 290 is not electrically
conductive, but is thermally conductive to allow heat from the
heating element inside to be transferred to the patient's eyelid.
The lens 290 can be constructed out of a plastic, including a clear
plastic such as LEXAN HPS2 for example. Further, the lens 290 can
be constructed from a biocompatible material, such as
polymethylmethacrylate (PMMA), epoxy, or other materials well known
to those skilled in the art. The lens 290 may be flexible, but
ideally should be only minimally compressible to fit against the
patient's eyeball.
[0117] The lens 290 also contains a lid warmer platform or tab 294
that is attached to the lens 290. The lid warmer platform 294 may
be connected perpendicularly to the lens 290 such that it extends
away from the patient's eye when installed. The lid warmer platform
294 provides a handle for insertion and movement or adjustment of
the lens 290 and its heating element. It can also support a lens
electrical interface 296 to allow the lens 290 to electrically
connect the heating element inside the lens 290 to the controller
272 via the interface 276. The controller 272 can then apply
electrical energy to the heating element to generate heat within
the lens 290 and thus to the inside of the patient's eyelid when
installed. Second, it provides a support structure for interface
circuitry 298. The interface circuitry 298 provides electrical
connections for energizing the heating element and communicating
temperature measured at the lens 290 back to the controller 272 for
heat regulation. A heat regulating circuit like that previously
illustrated and discussed may be employed.
[0118] FIG. 27 illustrates a cross-sectional view of the lid warmer
employing the lens 290 illustrated in FIGS. 24-26 to further
illustrate heat delivery components and features of the lid warmer,
according to this embodiment. The lens 290 is formed by a
donut-shaped scleral side 293 being attached to an eyelid side 292.
The scleral side 293 contains an orifice 295 so that the heating
element 306 is located around the perimeter of the eye away from
the cornea and towards the trabecular meshwork 22 The scleral side
293 of the lens 290 contains a bend 300 around its circumference
edge to provide an attachment edge 302 to support attachment of the
eyelid side 292. Because of the bend 300, a hollow chamber 304 is
formed inside the lens 290. The heating element 306 abuts against
the scleral side 293 of the lens 290 so that the heat is generated
adjacent the eye globe to transfer the heat to the trabecular
meshwork 22. The hollow chamber 304 insulates the cornea from the
heating element 306 contained inside the lens 290. The heating
element 306 is attached to the interface circuitry 298 via a fused
link 308, which is then attached to the controller 272 via the lid
warmer platform 294 being attached to the controller interface 276.
In this manner, the controller 272 can cause the heating element
306 inside the lens 290 to generate heat by applying an electrical
signal to the interface circuitry 298, which is connected to the
heating element 306. If the temperature exceeds the threshold
temperature level of the fused link 308, the link 308 would melt
and create an open circuit to disable the heating element 306 for
safety reasons. Alternatively, the fused link 308 could be a
thermal link provided as an integrated part of the heating element
306 such that the fused link 308 would melt and create an open
circuit at a given threshold temperature.
[0119] The heating element 306 may be provided in any form or
material. The heating element 306 may be a resistive type heater, a
thick film heater, or any one of a number of other types, such as a
"flex circuit" (etched metal on flexible substrate) well known to
those skilled in the art. The heating element 306 can be formed to
the shape of the lens 290. In the illustrated example, the heating
element 306 is a material that is both electrically and thermally
conductive. This may be important. The electrical conductivity
characteristic allows current to be applied to the heating element
306 to generate resistive heat. The thermal conductivity
characteristic serves to evenly distribute the resistive heat over
the entire heating element 306 to more evenly distribute the heat
to the patient's eyelid. Without these characteristics, it may be
more difficult to regulate heat generated by the heating element to
efficiently and effectively loosen or relax protein clogs or other
inhibitors in the trabecular meshwork. Examples include the E5101
carbon-loaded polyphenylene sulfide and the E2 liquid crystal
polymer, both manufactured by Cool Polymers, Inc.
[0120] The size of the lens 290 may also play a part in the heating
element 306 selection and the amount of heat it must generate to be
effective. The lens 290 distributes heat generated by the heating
element 306. A larger lens 290 may distribute the heat generated by
the heating element 306 more uniformly and over a larger surface
area. Also note that the application of heat to the patient's eye
globe does not necessarily have to include an embedded heating
element 306 in the lens 290. Heat application may be provided as
part of the environment, such as air for example. The amount of
heat applied, the temperature reached at the trabecular meshwork as
a result, where the heat is applied on the patient's eyelid or
surrounding tissue, and the duration of heat applied can control
the selection of the heating source.
[0121] In addition to the insulation provided by the material used
to construct the lens 290, the lens 290 may also contain an
integrated insulator inside the chamber 304 as an additional
measure of insulation. Insulation prevents substantial heat from
reaching the inner cornea. As employed herein, the term "insulate"
or "insulation" is intended to include any component or material
and/or specific geometries of components or materials, wherein
there is greater resistance to thermal conduction or radiation
towards the surface of the eye than towards the eyelid. Stated
alternatively, in the insulator thermal energy radiates more easily
towards the eye globe that the eyelids 291A, 291B. Although not
necessary, this may assist in greater comfort to the patient during
treatment. In the lens 290 example of FIG. 27, the integrated
insulator is air and is formed by the hollow chamber 304 that
exists by the space left by the heating element 306 not filling up
the entire volume of the hollowchamber 304. Further, the hollow
chamber 304 may be provided in the form a biocompatible material
such as polymethylmethacrylate (PMMA), epoxy, or other materials
well known to those skilled in the art. The hollow chamber 304 may
be flexible, but ideally should be only minimally compressible, as
will become clear from the discussion that follows. The heating
element 306 is biased according to its location in the lens 290,
and in particular to be located behind the integrated insulator, to
produce heat towards the eye globe the trabecular meshwork.
[0122] FIG. 28 supplements FIG. 27 to illustrate the interface
components between the controller 272 and the disposable component
274 at a system level. The controller 272 of the heat and force
application device 270 contains a temperature control system 322,
which is wired via wiring 316 to the disposable component 274. The
temperature control system 322 is the control component within the
controller 272 that controls the heat applied to the patient's eye
via the lens 290. The temperature control system 322 may operate
similarly or just as the heating regulating circuit 74, previously
described above.
[0123] Those skilled in the art will recognize improvements and
modifications to the preferred embodiments of the present
invention. All such improvements and modifications are considered
within the scope of the concepts disclosed herein and the claims
that follow.
* * * * *