U.S. patent application number 16/358754 was filed with the patent office on 2019-09-19 for methods and apparatuses for treatment of meibomian glands.
The applicant listed for this patent is TearScience, Inc.. Invention is credited to Stephen M. Grenon, Donald R. Korb, Timothy R. Willis.
Application Number | 20190282251 16/358754 |
Document ID | / |
Family ID | 46326189 |
Filed Date | 2019-09-19 |
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United States Patent
Application |
20190282251 |
Kind Code |
A1 |
Korb; Donald R. ; et
al. |
September 19, 2019 |
METHODS AND APPARATUSES FOR TREATMENT OF MEIBOMIAN GLANDS
Abstract
Methods and apparatuses of treating meibomian glands are
disclosed. An apparatus suitable to treat meibomian glands
comprises a heat source, a controller, and a pressure applicator.
The heat source is configured to apply regulated heat to an eyelid
containing at least one meibomian gland to reach a temperature
adequate to melt at least one obstruction within the at least one
meibomian gland and place the at least one obstruction in a melted
state. The controller is configured to maintain the regulated heat
for a time period adequate to melt the at least one obstruction and
place the at least one obstruction in the melted state. The
pressure applicator is configured to be placed into direct contact
with the eyelid and apply a pressure over at least a portion of the
eyelid to express the at least one obstruction from the at least
one meibomian gland.
Inventors: |
Korb; Donald R.; (Boston,
MA) ; Willis; Timothy R.; (Raleigh, NC) ;
Grenon; Stephen M.; (Durham, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TearScience, Inc. |
Morrisville |
NC |
US |
|
|
Family ID: |
46326189 |
Appl. No.: |
16/358754 |
Filed: |
March 20, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14510863 |
Oct 9, 2014 |
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16358754 |
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13183901 |
Jul 15, 2011 |
9216028 |
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14510863 |
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11541418 |
Sep 29, 2006 |
7981145 |
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13183901 |
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11434054 |
May 15, 2006 |
8083787 |
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11541418 |
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11434033 |
May 15, 2006 |
8915253 |
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11541418 |
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11434446 |
May 15, 2006 |
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11434033 |
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60700233 |
Jul 18, 2005 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2007/0004 20130101;
A61F 2007/0059 20130101; A61F 9/00772 20130101; A61H 2015/0014
20130101; A61B 17/22004 20130101; A61F 7/02 20130101; A61B 18/12
20130101; A61H 7/00 20130101; A61B 2018/048 20130101; A61N 7/00
20130101; A61B 2018/046 20130101 |
International
Class: |
A61B 17/22 20060101
A61B017/22; A61F 9/007 20060101 A61F009/007; A61H 7/00 20060101
A61H007/00; A61F 7/02 20060101 A61F007/02 |
Claims
1. An apparatus for treating meibomian glands having a meibomian
gland channel and a meibomian gland orifice at a top of the
meibomian gland channel, comprising: a heat source configured to
apply regulated heat to an eyelid containing at least one meibomian
gland to reach a temperature adequate to melt at least one
obstruction within the at least one meibomian gland and place the
at least one obstruction in a melted state; a controller configured
to maintain the regulated heat for a time period adequate to melt
the at least one obstruction and place the at least one obstruction
in the melted state; and a pressure applicator configured to be
placed into direct contact with the eyelid and apply a pressure
over at least a portion of the eyelid to express the at least one
obstruction from the at least one meibomian gland.
2. The apparatus according to claim 1, wherein the at least one
obstruction is located within the meibomian gland channel, and the
heat source is configured to apply the regulated heat to reach a
temperature adequate to melt the at least one obstruction located
in the meibomian gland channel; the controller is configured to
maintain the regulated heat for the time period adequate to place
the at least one obstruction located in the meibomian gland channel
in the melted state; and the pressure applicator is configured to
apply a pressure to the meibomian gland channel to express the at
least one obstruction from within the meibomian gland channel
through the meibomain gland orifice.
3. The apparatus according to claim 1, wherein the time period
comprises approximately 10 to 60 minutes.
4. The apparatus according to claim 1, wherein the pressure
applicator is at least partially heated.
5. The apparatus according to claim 1, wherein the heat source is
configured to apply the regulated heat until the temperature
reaches approximately 45 degrees Celsius.
6. The apparatus according to claim 1, wherein the heat source is
configured to apply the regulated heat until the temperature
reaches between approximately 44 and 47 degrees Celsius.
7. The apparatus according to claim 1, wherein the heat source is
configured to apply the regulated heat until the temperature is at
least 37 degrees Celsius.
8. The apparatus according to claim 1, wherein the pressure
applicator is further configured to apply the pressure within 3
minutes after an end of the time period.
9. The apparatus according to claim 2, wherein the pressure
applicator is further configured to milkingly express the melted at
least one obstruction located within the meibomian gland channel
from within the meibomian gland channel through the meibomian gland
orifice of one or more of the meibomian glands.
10. The apparatus according to claim 1, wherein at least one of the
heat source and the controller is further configured to repeat the
applying and maintaining of the regulated heat after a time
interval to maintain flow of fluids from the meibomian glands.
11. The apparatus according to claim 10, wherein the pressure
applicator is further configured to repeat the applying of the
pressure at the time interval to maintain the flow of fluids from
the meibomian glands.
12. The apparatus according to claim 1, wherein the pressure
applicator is further configured to apply mechanical energy
stimulation to the eyelid.
13. The apparatus according to claim 1, wherein the pressure
applicator is further configured to squeeze the eyelid and apply a
constant compressive force to the eyelid.
14. The apparatus according to claim 1, wherein the pressure
applicator is further configured to apply vibratory stimulation to
the eyelid.
15. The apparatus according to claim 1, wherein the pressure
applicator is further configured to apply a pulsating compressive
force to the eyelid.
16. The apparatus according to claim 1, wherein at least one of the
heat source and the controller is configured to remove the applying
of the regulated heat from the eyelid to allow the pressure
applicator to apply the pressure to the meibomian glands.
17. The apparatus according to claim 1, wherein the heat source is
configured to apply the regulated heat to the meibomian gland
channel of one or more of the meibomian glands during the applying
of pressure to the one or more of the meibomian glands.
18. The apparatus according to claim 1, wherein the heat source
further comprises a heating element.
19. The apparatus according to claim 18, further comprising a
thermal heat sink coupled to the heating element in order to
transfer heat from the heating element to the eyelid.
20. The apparatus according to claim 18, wherein the heat source
further comprises an insulator coupled to the heating element in
order to reduce heat loss.
21. The apparatus according to claim 20, further comprising a back
plate that couples to the insulator.
22. The apparatus according to claim 1, wherein the heat source is
configured to apply light energy to the eyelid containing the at
least one meibomian gland to reach the temperature adequate to melt
the at least one obstruction within the at least one meibomian
gland and place the at least one obstruction in a melted state.
Description
CROSS REFERENCE TO RELATED DOCUMENTS
[0001] This application is a Divisional of co-pending U.S. patent
application Ser. No. 14/510,863, filed Oct. 9, 2014 and entitled
Methods and Apparatuses for Treatment of Meibomian Glands to Korb
et al., which is a Continuation of U.S. patent application Ser. No.
13/183,901, filed Jul. 15, 2011 and entitled Apparatuses for
Treatment of Meibomian Glands to Korb et al., issued as U.S. Pat.
No. 9,216,028, which is a Continuation of U.S. patent application
Ser. No. 11/541,418, filed Sep. 29, 2006 and entitled Treatment of
Meibomian Glands to Korb et al., issued as U.S. Pat. No. 7,981,145,
which in turn is a Continuation-in-Part of U.S. patent application
Ser. No. 11/434,054, filed May 15, 2006 and entitled Method and
Apparatus for Treating Meibomian Gland Dysfunction to Korb, et al.,
issued as U.S. Pat. No. 8,083,787, which claims priority benefit of
U.S. Provisional Application No. 60/700,233, filed Jul. 18, 2005;
and is further a Continuation-in-Part of U.S. patent application
Ser. No. 11/434,033, filed May 15, 2006 entitled Method and
Apparatus for Treating Gland Dysfunction Employing Heated Medium,
to Grenon et al., issued as U.S. Pat. No. 8,915,253; and is further
a Continuation-in-Part of U.S. patent application Ser. No.
11/434,446, filed May 15, 2006 entitled Method and Apparatus for
Treating Gland Dysfunction to Korb et al., now abandoned, each of
which is hereby incorporated by reference in its entirety.
COPYRIGHT NOTICE
[0002] A portion of the disclosure of this patent document contains
material which is subject to copyright protection. The copyright
owner has no objection to the facsimile reproduction of the patent
document or the patent disclosure, as it appears in the Patent and
Trademark Office patent file or records, but otherwise reserves all
copyright rights whatsoever.
FIELD
[0003] This invention relates generally to treatment of mammalian
eyes. More particularly, this invention relates treatments of
obstruction of meibomian glands by use of various combinations of
heat to melt certain obstructions (or melt material binding solid
particles forming an obstruction), mechanical action to clear the
obstruction and pharmaceutical treatment once the obstruction has
been cleared.
BACKGROUND
[0004] The human body contains a number of glands including the
lacrimal and meibomian glands of the eye, the sebaceous or
pilo-sebaceous hair glands on the face and underarms, and the
mammary glands in the breasts. These glands may malfunction due to
age, irritation, environmental conditions, cellular debris,
inflammation, hormonal imbalance and other causes. One common
disease state of the eyelid glands is the restriction or stoppage
of the natural flow of fluid out of the gland caused by an
obstruction.
[0005] In the human eye, the tear film covering the ocular surfaces
is composed of three layers. The innermost layer in contact with
the ocular surface is the mucus layer comprised of many mucins. The
middle layer comprising the bulk of the tear film is the aqueous
layer, and the outermost layer is a thin (less than 250 nm) layer
comprised of many lipids known as "meibum" or "sebum". The sebum is
secreted by the meibomian glands, enlarged specialized
sebaceous-type glands (hence, the use of "sebum" to describe the
secretion) located within both the upper and lower eye lids, with
orifices designed to discharge the lipid secretions onto the lid
margins, thus forming the lipid layer of the tear film. The typical
upper eyelid has about 25 meibomian glands and the lower eyelid has
about 20 meibomian glands, which are somewhat larger than those
located in the upper lid. The meibomian gland comprises various
sac-like acini which discharge the secretion into the main central
duct of the gland. The secretion then passes into the orifices
which are surrounded by smooth muscle tissue and the muscle of
Riolan which are presumed to aid in the expression of sebum. The
meibomian gland orifices open onto the lid margin at and around the
junction of the inner mucous membrane and the outer skin of the
eyelids termed the mucocutaneous junction.
[0006] Specifically, as illustrated in the above patent
applications, each meibomian gland has a straight long central duct
lined with four epithelial layers on the inner surface of the duct.
Along the length of the central duct there are multiple lateral
out-pouching structures, termed acini where the secretion of the
gland is manufactured. The inner lining of each acinus differs from
the main central duct in that these specialized cells provide the
secretions of the meibomian gland. The secretions flow from each
acinus to the duct. While it has not been established with
certainty, there appears to be a valve system between each acinus
and the central duct to retain the secretion until it is required,
at which time it is discharged in to the central duct. The
meibomian secretion is then stored in the central duct and is
released through the orifice of each gland onto the lid margin.
Blinking and the squeezing action of the muscle of Riolan
surrounding the meibomian glands are thought to be the primary
mechanism to open the orifice for the release of secretion from the
meibomian gland.
[0007] The upward phase of blinking causes the upper lid to pull a
sheet of the lipids secreted by the meibomian glands upward and
over the other two layers of the tear film, thus forming a type of
protective coating which limits the rate at which the underlying
layers evaporate. Thus, it will be seen that a defective lipid
layer or an incorrect quantity of such lipids can result in
accelerated evaporation of the aqueous layer which, in turn, causes
symptoms such as itchiness, burning, irritation, and dryness, which
are collectively referred to as "dry eye".
[0008] Dry eye states have many etiologies. A common cause of
common dry eye states is a disorder where the glands are obstructed
or occluded, usually referred to as "meibomian gland dysfunction"
(MOD). As employed herein the terms "occluded" and "obstruction" as
they relate to meibomian gland dysfunction are defined as partially
or completely blocked or plugged meibomian glands, or any component
thereof, having a solid, semi-solid or thickened congealed
secretion and/or plug, leading to a compromise, or more
specifically, a decrease or cessation of secretion. Also with a
reduced or limited secretion the meibomian gland may be compromised
by the occluded or obstructive condition as evidenced by a
yellowish color indicating a possible infection state, or may be
otherwise compromised so that the resulting protective lipid
protective film is not adequate.
[0009] Meibomitis, an inflammation of the meibomian glands leading
to their dysfunction, is usually accompanied by blepharitis
(inflammation of the lids). Meibomian gland dysfunction may
accompany meibomitis, or meibomian gland dysfunction may be present
without obvious lid inflammation. Meibomian gland dysfunction is
frequently the result of keratotic obstructions which partially or
completely block the meibomian gland orifices and/or the central
duct (canal) of the gland, or possibly the acini or acini valves
(assuming they do in fact exist) or the acini's junction with the
central duct. Such obstructions compromise the secretory functions
of the individual meibomian glands. More particularly, these
keratotic obstructions can comprise combination of bacteria,
sebaceous ground substance, dead, and/or desquamated epithelial
cells, see, Korb et al., Meibomian Gland Dysfunction and Contact
Lens Intolerance, Journal of the Optometric Association, Vol. 51,
Number 3, (1980), pp. 243-251. While meibomitis is obvious by
inspection of the external lids, meibomian gland dysfunction may
not be obvious even when examined with the magnification of the
slit-lamp biomicroscope, since there may not be external signs, or
the external signs may be so minimal that they are overlooked. The
external signs of meibomian gland dysfunction without obvious lid
inflammation may be limited to subtle alterations of the meibomian
gland orifices, overgrowth of epithelium over the orifices, and
pouting of the orifices of the glands with congealed material
acting as obstructions. In severe instances of meibomian gland
dysfunction without obvious lid inflammation the changes may be
obvious, including serrated or undulated lid margins, orifice
recession and more obvious overgrowth of epithelium over the
orifices, and pouting of the orifices.
[0010] Hormonal changes, which occur during menopause, and
particularly changing estrogen levels, can result in thickening of
the oils secreted by the meibomian glands which results in clogged
gland orifices. Further, decreased estrogen levels may also enhance
conditions under which staphylococcal bacteria can proliferate.
This can cause migration of the bacteria into the glands, thus
resulting in a decreased secretion rate.
[0011] When the flow of secretions from the meibomian gland is
restricted due to the existence of an obstruction, cells on the
eyelid margin have been observed to grow over the gland orifice
thus further restricting sebum flow and exacerbating the dry eye
condition. Additional factors which may cause or exacerbate
meibomian gland dysfunction include, age, disorders of blinking,
activities such as computer use which compromise normal blinking,
contact lens wear and hygiene, cosmetic use, or other illness,
particularly diabetes.
[0012] The state of an individual meibomian gland can vary from
optimal, where clear meibomian fluid is produced; to mild or
moderate meibomian gland dysfunction where milky fluid or
inspissated or creamy secretion is produced; to total blockage
where no secretion of any sort can be obtained (see Korb, et al.,
"Increase in Tear Film Lipid Layer Thickness Following Treatment of
Meibomian Gland Dysfunction", Lacrimal Gland, tear Film, and Dry
Eye Syndromes, pp. 293-298, Edited by D. A. Sullivan, Plenum Press,
New York (1994)). Significant chemical changes of the meibomian
gland secretions occur with meibomian gland dysfunction and
consequently, the composition of the naturally occurring tear film
is altered, which in turn, contributes to ocular disease which is
generally known as "dry eye".
[0013] While the tear film operates as a singular entity and all of
the layers thereof are important, the lipid layer, which is
secreted from the meibomian glands, is of particular significance
as it functions to slow the evaporation of the underlying layers
and to lubricate the eyelid during blinking which prevents dry
eye.
[0014] Thus, to summarize, the meibomian glands of mammalian (e.g.,
human) eyelids secrete oils that prevent evaporation of the tear
film and provide lubrication to the eye and eyelids. These glands
can become blocked or plugged by various mechanisms leading to
so-called "dry eye syndrome". While not the only cause, meibomian
gland dysfunction (MGD) is known to be a major cause of dry eye
syndrome. The disorder is characterized by a blockage of some sort
within the meibomian glands or at their surface preventing normal
lipid secretions from flowing from the meibomian glands to form the
lipid layer of the tear film.
[0015] Such secretions serve to prevent evaporation of the tear
film and lubricate the eye and eyelids, hence their absence can
cause dry eye syndrome. Obstructions or occlusions of the meibomian
glands may be present over or at the orifice of the gland in the
main channel of the gland which may be narrowed or blocked, or
possibly in other locations including the passages from the acini
to the main channel.
[0016] It has been theorized that the acini of the glands may have
valves at their junction with the main channel of the gland. The
inventors theorize that if these valves exist, they may also become
obstructed in some instances leading to reduced or blocked flow
from the acini. These obstructions or occlusions may have various
compositions.
[0017] In response to the foregoing, various treatment modalities
have been developed in order to treat the dry eye condition,
including drops which are intended to replicate and replace the
natural tear film, pharmaceuticals which are intended to stimulate
the tear producing cells, and various heating devices which are
designed to assist in unclogging the meibomian glands. Other
techniques involve manual expression of the glands.
[0018] Eye drops such as Refresh.RTM., Soothe.RTM. and Systane.RTM.
brand eye drops are designed to closely replicate the naturally
occurring healthy tear film. However, their use and administration
is merely a treatment of symptoms and not of the underlying cause.
Further, the use of drops is generally for an indefinite length of
time and consequently, extended use can become burdensome and
costly.
[0019] Pharmaceutical modalities such as the use of tetracycline
have also been suggested to treat meibomian gland dysfunction and
one such treatment is disclosed in United States Patent Publication
no. US2003/011426 titled "Method for Treating Meibomian Gland
Disease", U.S. Pat. No. 6,455,583 titled "Method for Treating
Meibomian Gland Disease" to Pflugfelder et al. and PCT Publication
No. WO 99/58131 titled "Use of Tetracyclines for Treating Meibomian
Gland Disease". However, this treatment has not proven to be
universally clinically effective, and it may be unnecessary in
cases where meibomian gland dysfunction is the result of
obstruction of the gland without infection. The use of
corticosteroids have also been proposed to treat meibomian gland
dysfunction as disclosed in U.S. Pat. No. 6,153,607 titled
"Non-preserved Topical Corticosteroid for Treatment of Dry Eye,
filamentary Keratitis, and Delayed Tear Clearance (or Turnover) to
Pflugfelder et al. Again, this proposed treatment appears to treat
the symptom of dry eye, as opposed to treatment of the underlying
cause. Additionally, the use of topically applied androgens or
androgen analogues have also been used to treat acute dry eye signs
and symptoms in Keratoconjuctivitis Sicca as disclosed in U.S. Pat.
Nos. 5,958,912 and 6,107,289 both titled "Ocular Therapy in
Keratoconjunctivitis Sicca Using Topically Applied Androgens or
TGF-.beta." and both issued to Sullivan.
[0020] Most knowledgeable doctors agree that heat is beneficial in
treating MGD. Depending upon the nature of the obstruction, heat
may be beneficial in actually melting or loosening the obstructing
material, permitting the gland to begin production and excretion of
lipids and other fluids more freely.
[0021] One modality for the heat treatment of meibomian gland
dysfunction is disclosed in European Patent Application serial no.
PCT/GB2003/004782 titled "Eyelid Margin Wipes Comprising Chemical
Means for Temperature Adjustment". As disclosed in this patent
application, a wipe is provided wherein prior to use, a chemical
agent is activated that will heat the wipe to about 32.degree. C.
to about 40.degree. C. The hot wipe is then applied to the lids and
manual expression can then be used to unclog the ducts. This method
is not without its drawbacks in that lid irritation can be
exacerbated by non-specific heating.
[0022] Another method of heating the eyelids and meibomian glands
uses near infrared (NIR) radiation. More specifically, two hard eye
patches were attached to an eye mask according to the pupillary
distance of the subject. The eye mask was held in place by an
elastic headband. Each patch employed 19 light emitting diodes,
emitting near infrared radiation from 850 nm to 1050 nm, with a
peak at 940 nm. The device produced 10 mW/cm.sup.2 of energy
operating on electrical power. Goto, E., et al., Treatment of
Non-Inflamed Obstructive Meibomian Gland dysfunction by an Infrared
Warm Compression Device, British Journal of Ophthalmology, Vol. 86
(2002), pp. 1403-1407. This device is designed as a non-contact
infrared heating mask using IR light emitting diodes. However,
there are many potential problems with use of an IR heating
mechanism. For example, the IR Heat can penetrate beyond the eyelid
into the cornea which is undesirable, and could ultimately cause
cataracts or other damage. Additionally, the IR mask heater places
no pressure whatsoever on the eyelid (despite the description as a
compression device) which we have determined is useful to expel the
blockage. Moreover, tests conducted on a sample of this mask
revealed that in spite of the potential dangers, the mask produced
very little actual heat.
[0023] United States Patent Publication US2004/0237969 titled
"Therapeutic Eye and Eye Lid Cover" comprises a pair of goggles
that are adapted to deliver heated saturated air to the eyelids and
particularly to the meibomian glands, again to heat the gland. Heat
treatment of the eyes is also discussed in the article titled "Tear
Film Lipid Layer Thickness and Ocular Comfort after Meibomian
Therapy via Latent Heat with a Novel Device in Normal Subjects by
Mitra et al, published in Eye, (2004) at pages 1-4.
[0024] United States Patent Publication US2003/0233135 titled
"Method and Apparatus for Preventing and Treating Eyelid Problems"
to Yee attempts to clear the plugged meibomian glands by means of
electrical stimulation of the muscle of Riolan which the invention
presumed to aid in the expression of the meibomian gland
secretion.
SUMMARY OF CERTAIN EMBODIMENTS
[0025] It is an object of certain embodiments consistent with the
present invention to provide a method for treatment of mammalian
eyelids.
[0026] It is another object of certain embodiments consistent with
the present invention to provide a method of treatment that first
produces a flow of lipids from the meibomian glands of the upper
and/or lower eyelids of either or both eyes in order to aid in the
clearing of certain types of obstructions that may be present in or
about the meibomian glands, followed by pharmacological treatment
to assist in maintaining the flow of lipids or otherwise assist in
the promoting lubrication of the eyes.
[0027] In one embodiment consistent with the present invention a
method of treating mammalian meibomian glands involves clearing the
glands by applying a regulated heat to an eyelid containing the
meibomian glands to a temperature adequate to melt obstructions in
the meibomian glands, thereby placing the obstruction in a fluid or
suspension (melted) state, and maintaining the heat for a time
period adequate to melt the obstructions and place the obstructions
in the fluid or suspension (melted) state. The glands can then be
mechanically treated to express fluid from the glands, wherein the
treating is carried out either during the time period or after the
time period but while the obstruction remains in the fluid or
suspension state. In most instances, this should be carried out
within about 90 seconds of the end of the time period. Subsequent
pharmacological treatment of the glands by use a pharmacological
agent (topical or systemic) can then be used to assist in
maintaining proper flow of lipids from the glands or otherwise
assist in the promoting lubrication of the eyes.
[0028] In accordance with certain embodiments, the time period can
be approximately 10 to 60 minutes, and approximately 15 minutes is
generally suitable for mild to moderate cases of MGD. In more
severe cases, treatments of 30-45 minutes may be required, and for
very severe cases, up to and beyond 60 minutes of heat treatment
may be needed. These times assume a target temperature of 44-47
degrees with 45 degrees C. being preferred, and may possibly be
reduced somewhat for higher temperatures or extended 30 somewhat
for lower temperatures. Temperatures can range from 37 degrees
Celsius and up.
[0029] In certain embodiments, the mechanical treatment is carried
out by at least one of application of constant pressure, vibratory
energy, mechanical energy, pulsating mechanical stimulation,
squeezing, milkingly expressing the fluid from one or more of the
glands while simultaneously applying heat, or applying vibratory
stimulation to the eyelid while simultaneously applying heat.
[0030] In another embodiment, a method of treating meibomian gland
dysfunction in a mammal wherein an occlusion blocks at least a
portion of the flow of naturally occurring secretions out of a
gland channel orifice involves applying a regulated heat source
proximate to the gland channel orifice for a selected time and at a
selected temperature adequate to soften or liquefy at least a
portion of the occlusion; mechanically treating the gland channel
orifice while the at least a portion of the occlusion remains
softened or liquefied such that at least a portion of the occlusion
is removed; subsequently treating the mammal with a pharmacological
agent which promotes the free flow of lipids from the meibomian
gland or otherwise assist in the promoting lubrication of the
eyes.
[0031] In another embodiment, a method of treating meibomian gland
dysfunction in a mammal wherein an occlusion blocks at least a
portion of the flow of naturally occurring secretions out of a
gland channel orifice involves applying a regulated heat source
proximate to the gland channel orifice for a selected time and at a
selected temperature adequate to loosen, breakup, fracture, soften
or liquefy at least a portion of the occlusion; mechanically
treating the gland channel orifice prior to reversal of the effects
of the application of the regulated heat source such that at least
a portion of the occlusion is removed; subsequently treating the
mammal with a pharmacological agent which promotes the free flow of
lipids from the meibomian gland or otherwise assist in the
promoting lubrication of the eyes.
[0032] The above overviews are intended to illustrate exemplary
embodiments which will be best understood in conjunction with the
detailed description to follow, and are not intended to limit the
scope or meaning of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Certain illustrative embodiments illustrating organization
and method of operation, together with objects and advantages may
be best understood by reference detailed description that follows
taken in conjunction with the accompanying drawings in which:
[0034] FIG. 1 depicts upper and lower human eyelids showing the
meibomian glands.
[0035] FIG. 2 is a cutaway view of an illustrative meibomian gland
20.
[0036] FIG. 3 is a cutaway view meibomian gland 20 illustrating
several obstructed areas.
[0037] FIG. 4 is a graph of inner and outer surface temperatures of
a patient's eyelid while the outer surface of the eyelid is heated
to about 45 degrees C.
[0038] FIG. 5 is a flow chart depicting a treatment process
consistent with certain embodiments of the present invention.
[0039] FIG. 6 is a flow chart depicting another treatment process
consistent with certain embodiments of the present invention.
[0040] FIG. 7A is a perspective view of a system for clearing
obstructed meibomian glands.
[0041] FIG. 7B is a broken away side view of the probe tip employed
in the embodiment of FIG. 7A.
[0042] FIG. 8A is a perspective view of a second embodiment of the
probe tip according to the present invention.
[0043] FIG. 8B is a broken away side view of the probe tip of FIG.
8A.
[0044] FIG. 8C is a broken away side view of the probe tip of FIGS.
7A and 8A in place on an eye lid.
[0045] FIG. 9 is broken away side view of an alternate for clearing
obstructed meibomian glands according to the present invention.
[0046] FIG. 10A is a side view of an alternate embodiment of the
probe tip having rollers for clearing obstructed meibomian glands
according to the present invention.
[0047] FIG. 10B is a side view of another alternate embodiment of
the probe tip having rollers for clearing obstructed meibomian
glands according to the present invention.
[0048] FIG. 11 is a side view of another alternate embodiment of
the probe tip having rollers for clearing obstructed meibomian
glands according to the present invention.
[0049] FIG. 12 is a perspective view of a suction device for
clearing glands according to the present invention.
[0050] FIG. 13 is a side view of another embodiment of the
apparatus for clearing meibomian glands according to the present
invention.
[0051] FIG. 14A is a schematic view of another embodiment of the
apparatus for clearing meibomian glands according to the present
invention.
[0052] FIG. 14B is an exploded view of the hand-held probe of the
embodiment of FIG. 14A.
[0053] FIG. 14C is a side view of the hand-held probe of FIGS. 14A
and 14B applying force to an eyelid.
[0054] FIG. 15A is a perspective view of another embodiment of the
meibomian gland treatment apparatus in the form of the
hydro-oculator according to the present invention.
[0055] FIG. 15B is a side view of the hydro-oculator of FIG.
15A.
[0056] FIG. 15C is a schematic side view of the hydro-oculator
according to the present invention in place against the lower
eyelid.
[0057] FIG. 15D is a schematic side view of the hydro-oculator
according to the present invention in place against the lower
eyelid and showing the fluid filled bladder beginning to
expand.
[0058] FIG. 15E is a schematic side view of the hydro-oculator
according to the present invention in place against the lower
eyelid and showing the fluid filled bladder in a further expanded
state.
DETAILED DESCRIPTION
[0059] While this invention is susceptible of embodiment in many
different forms, there is shown in the drawings and will herein be
described in detail specific embodiments, with the understanding
that the present disclosure of such embodiments is to be considered
as an example of the principles and not intended to limit the
invention to the specific embodiments shown and described. In the
description below, like reference numerals are used to describe the
same, similar or corresponding parts in the several views of the
drawings.
[0060] The terms "a" or "an", as used herein, are defined as one or
more than one. The term "plurality", as used herein, is defined as
two or more than two. The term "another", as used herein, is
defined as at least a second or more. The terms "including" and/or
"having", as used herein, are defined as comprising (i.e., open
language). The term "coupled", as used herein, is defined as
connected, although not necessarily directly, and not necessarily
mechanically. The term "program" or "computer program" or similar
terms, as used herein, is defined as a sequence of instructions
designed for execution on a computer system. A "program", or
"computer program", may include a subroutine, a function, a
procedure, an object method, an object implementation, in an
executable application, an applet, a servlet, a source code, an
object code, a shared library/dynamic load library and/or other
sequence of instructions designed for execution on a computer
system.
[0061] Reference throughout this document to "one embodiment",
"certain embodiments", "an embodiment" or similar terms means that
a particular feature, structure, or characteristic described in
connection with the embodiment is included in at least one
embodiment of the present invention. Thus, the appearances of such
phrases or in various places throughout this specification are not
necessarily all referring to the same embodiment. Furthermore, the
particular features, structures, or characteristics may be combined
in any suitable manner in one or more embodiments without
limitation.
[0062] The term "or" as used herein is to be interpreted as an
inclusive or meaning any one or any combination. Therefore, "A, B
or C" means "any of the following: A; B; C; A and B; A and C; Band
C; A, B and C". An exception to this definition will occur only
when a combination of elements, functions, steps or acts are in
some way inherently mutually exclusive.
[0063] As noted above, meibomian gland dysfunction (MGD) is known
to be a major cause of dry eye syndrome. The disorder is
characterized by a blockage of some sort within the meibomian
glands preventing normal lipid secretions from flowing through the
orifices and out of the glands to the tear film. Obstructions or
occlusions of the meibomian glands may be present at the orifice of
the gland, the main channel of the gland, or possibly in other
locations including the main channel of the gland which may be
narrowed or blocked. It has been theorized that the acini of the
glands may have valves at their junction with the main channel of
the gland, and that these valves may be obstructed in some
instances-leading to reduced or blocked flow from the acini. These
obstructions or occlusions may have various compositions.
[0064] Referring now to FIG. 1, the location of the meibomian
glands 10 are shown on the upper and lower eyelids 12 and 14
respectively. As briefly stated herein above, the upper lid
contains about 25 meibomian glands and the lower lid contains about
20 meibomian glands, with significant variation. As shown in
cross-sectional view of one gland 10 in FIG. 2, each gland includes
a central duct or channel 18 into which the secretion flows from
acini 19 and an orifice 20 which opens on to the eyelid margin and
through which the secretion flows in order to be added to the tear
film upon blinking. It will be seen that the glands are of
different size, depending upon the location in the eyelid and that
the orifice 20 is narrower than the central duct 18.
[0065] Obstruction composition will vary with the etiology which
produced it. However, the obstruction will, in most cases observed
to the present, be a combination of, dead cells, bacteria,
desquamated cells, and desquamated cells aggregating in keratotic
clusters, milky fluid, inspissated or creamy secretions, or any
combination of the foregoing in solid, semi-solid and thickened
forms. Referring to FIG. 3, a simplified view of exemplary
obstructions to gland 10 are depicted. In this example, which is by
no means necessarily representative' of all meibomian gland
obstructions, as explained above, a solid or semi-solid or
thickened plug 24 is depicted which is fully occluding the orifice
20 of gland 10. Another obstruction 26 is shown at a junction from
one of the acini with the central duct. As previously noted, this
may be the site of a valve in the gland structure, but embodiments
consistent with the present invention should not be limited by
theories of the actual meibomian gland structure.
[0066] A number of treatment techniques have been proposed to
restore these glands to normal functionality, but most doctors
agree that heat is beneficial in treating MGD. Depending upon the
nature of the obstruction, heat may be beneficial in actually
melting or loosening the obstructing material or material binding
solid particles to form the obstruction, permitting the gland to
begin production and excretion of lipids and other fluids more
freely. While the heat treatment methods described in the
Background section hereof have been found to have many drawbacks,
the heating techniques described in the above referenced copending
applications have been found effective and beneficial. Generally
speaking, these devices produce a regulated heating of the eyelid
(as measured at the outer surface thereof) by direct contact with
the eyelids to a therapeutic temperature of greater than 37 degrees
Celsius, and more preferably between about 44 and 47 degrees
Celsius with a target temperature of 45 degrees Celsius. However,
other devices may be used which are placed proximate to the eyelids
to provide heat to the meibomian glands.
[0067] The outside skin surface of the human eyelid has been
observed to be approximately 1-2 degrees Celsius cooler than body
temperature, with some variation. Increasing the temperature to at
least 37 can begin to provide therapeutic effect for milder cases
of MGD. One preferred range for treatment is 44 to 47 degrees
Celsius, with a target of 45 degrees Celsius has been found
effective and comfortable to the patient. In certain embodiments,
the mechanical energy treating is carried out during or immediately
after the end of the time period, and preferably with a heated
instrument so as to maintain the more fluid state of the
obstruction. Mechanical energy treatment can be carried out by any
mechanism that induces mechanical pressures, including but not
limited to vibratory, milking, mechanical pulsing pressure,
squeezing and other actions to express fluids from the glands
and/or dilate the duct or orifice of the meibomian gland. The
mechanical energy can take any form that applies mechanical
pressure on the meibomian glands to assist in pushing the blockage
or obstruction out of the gland while the obstruction is softened
by heat. Even higher temperatures (e.g., 50-55 degrees Celsius) can
be used (or pulsed for short periods), especially if the eyelid has
been anesthetized, in which case much hotter treatment for shorter
time can be used without permanent injury to the patient.
Generally, higher temperatures can be used for shorter periods of
time. Moreover, the temperature and time used should be
individualized based on the severity of the condition and the
tolerance of the patient. It has been found that lighter skinned
patients can generally tolerate less heat than darker skinned
patients, and darker skinned patients tend to exhibit less
inflammation as a result of exposure to the heat. Treatment times
and/or temperature can be adjusted to account for these
differences. Each of the above temperatures refers to the
temperature as measured at the outer surface of the eyelid.
[0068] Also, in certain embodiments, the patient is more
comfortable when the treatment begins at a lower temperature and
the temperature is raised over time. Hence, the temperature should
be regulated, where regulation should be interpreted to mean that
the actual temperature applied at the outer surface of the eyelid
is controlled or regulated in a manner that is repeatable. The
temperature profile for heat application may be a constant
temperature, or may have ramp-ups, ramp-downs, peaks, valleys, can
be pulsed, or can be modulated with various characteristics, etc.,
but such profile should be regulated so as to be repeatable. It has
also been found that modulating the temperature can result in a
higher average temperature than a constant temperature, and may be
useful in some applications.
[0069] This temperature can be maintained at a therapeutic
temperature for a treatment period of approximately 10-60 minutes
(or even beyond have been found safe and useful for some patients).
Either during or after such treatment by controlled heat,
mechanical expression of lipids and other fluids from the meibomian
glands has been found to clear obstructions which have essentially
melted or been placed in a suspension state (by virtue of melting
materials binding solids together). The above applications disclose
devices which generally apply a milking action to the eyelid to
express the fluids or suspensions or to otherwise mechanically
stimulate the movement of fluids from the glands--such fluid now
including melted or suspended materials causing the obstructions or
occlusions. In some instances, just gentle continuous force applied
to the eyelid will assist in expression of the fluids and
suspensions, while in others vibration can be used simultaneously
or immediately after the heating. For purposes of this document,
the term "melted" is to be interpreted to be inclusive of states in
which solid particles remain suspended within a liquid fluid.
[0070] In certain embodiments, such devices that apply regulated
heating of the eyelids are disclosed in U.S. patent application
Ser. No. 11/434,054, filed May 15, 2006 and entitled Method and
Apparatus for Treating Meibomian Gland Dysfunction to Korb, et al
and U.S. patent application Ser. No. 11/434,033, filed May 15, 2006
entitled "Melting Meibomian Gland Obstructions", to Steve Grenon,
et al. which are hereby incorporated by reference. In certain
embodiments, that device utilizes a heater unit having a heating
element that produces heat when an electrical signal is applied
thereto. A temperature regulator applies the electrical signal to
the heating element in order to achieve heating of the heating
element to a specified temperature range. An eyelid interfacing
mechanism couples the heater unit to the eyelid to achieve
regulated heating of the eyelid within the specified temperature
range.
[0071] Such a device provides regulated heating to a therapeutic
temperature. Conventional hot compresses and the IR heating
mechanisms described above background do not provide regulated
controlled heating at a therapeutic temperature and are less
effective than the regulated heat applied using the devices
described in the above-referenced patent applications that are
incorporated herein.
[0072] In another embodiment disclosed in this patent application,
an apparatus that provides controlled heat to at least one of a
patient's eyelids has a heater unit, and the heater unit having: a
heating element having first and second surfaces that produces heat
when an electrical signal is applied thereto; a thermal heat sink,
coupled to the first surface of the heating element in order to
transfer heat from the heating element to the eyelid; an insulator
coupled to the second surface of the heating element in order to
reduce heat loss from the second surface; and a back plate that
couples to the insulator. A temperature regulator applies the
electrical signal to the heating element in order to achieve
heating of the heating elements to a specified temperature range.
Goggles suitable for attaching to the patient's head and covering
the eyelid of the patient with a lenspiece are provided with the
lenspiece having a threaded aperture therein. A threaded shaft
passes through the threaded lenspiece and coupled to the heater
unit at the back plate so that the heater unit can be moved into
contact with the eyelid by screwing the shaft into the aperture
until contact with the eyelid is achieved.
[0073] Many variations in these embodiments are possible including,
but not limited to, providing a sensor that senses temperature and
provides temperature information to the temperature regulator. In
certain embodiment the eyelid interfacing mechanism comprises
goggles that are adjustably coupled to the heater unit in order to
move the heater unit to achieve contact with the eyelid. The
goggles may be adjustably coupled to the heater unit by a threaded
connection so that a position of the heater unit can be adjusted by
a threading action. In certain embodiments, the heater unit has a
thermal heat sink, coupled to a surface of the heating element in
order to transfer heat from the heating element to the eyelid. The
thermal heat sink may be, for example, at least one of a thermally
conductive rubber member, a thermally conductive silicon member, an
encapsulated fluid containing member, and a solid conductive
member. A thermally conductive gel, cream or liquid can be placed
between the heat sink and the eyelid to enhance thermal conduction
from the thermal heat sink to the eyelid.
[0074] In certain embodiments, the heater unit may have an
insulator coupled to a surface of the heating element in order to
reduce heat loss from the heating unit in a direction other than a
direction toward the eyelid. The thermal insulator may be one of a
non-thermally conductive foam element, a non-thermally conductive
rubber element, and a non-thermally conductive solid element in
certain embodiments. The temperature regulator may apply a pulse
width modulated electrical signal to the heating element in order
to regulate the heat produced thereby, and the pulse width
modulated electrical signal may be produced under control of the
control processor.
[0075] In certain embodiments, the temperature regulator may
incorporate a switch that selectively applies the electrical signal
to the heating element in order to regulate the heat produced
thereby. The electrical signal may be at least one of a current and
a voltage that is selectively applied to the heating element under
control of a control processor. The heater unit may have a flexible
portion that contacts the eyelid in order to conform to the eyelid
or may have a rigid portion that contacts the eyelid, and wherein
the rigid portion is shaped to conform to the shape of the eyelid,
or a combination thereof. The heater unit may have an adhesive for
attaching the heater unit directly to the eyelid or may be attached
to the eyelid by use of adhesive tape.
[0076] In certain embodiments, a user interface permits a user to
establish at least one of a time and a temperature for the
treatment. In certain embodiments, a vibration generator generates
vibration of the eyelid to stimulate secretion from the meibomian
glands, wherein the vibration generator may impart mechanical
energy to the eyelid having both an amplitude and frequency.
[0077] Other heating and/or pressure inducing devices are disclosed
in the above-referenced patent applications which are incorporated
herein by reference.
[0078] Hence, in view of the above, either immediately after
treatment with heat, or during such heat treatment, mechanical
treatment using, for example, constant force, squeezing (e.g., by
manual expression or otherwise), milking action or vibration can be
applied to the eyelid to stimulate clearing of the fluids or
suspensions from the meibomian glands. If mechanical treatment is
carried out after heat treatment, it should be carried out
immediately thereafter while the obstructive material of the
meibomian gland is in a melted state.
[0079] Referring now to FIG. 4, a graph depicts the inner surface
of an eyelid and an outer surface of an eyelid when a source of
constant heat at about 45 degrees C. was applied to an example
subject patient. It should be noted that the circulatory system
attempts to regulate the temperature of the eyelid, and blood flow
increases with the application of heat. For this patient, it took
approximately 4 minutes for the eyelid's outer surface to reach
about 45 degrees Celsius, and the inner surface of the eyelid never
reached this temperature--presumably because of the body's heat
regulatory mechanisms. Hence, if a 45 degree constant heat source
is used, it may take at least about 4 minutes to stabilize eyelid
temperature and reach a therapeutic temperature.
[0080] It is also noted from this graph, that when the heat source
is removed from the eyelid, the temperature drops very quickly to
body temperature. In virtually all cases, this temperature will
drop within 2-3 minutes, but more commonly, only about 30 seconds
to 90 seconds are required for the patient's eyelid temperature to
drop. In this example, the temperature dropped in temperature very
quickly over the first thirty seconds after removal of the heat.
During this short time period, some or all of the melted
obstruction may re-solidify. Hence, if manual expression techniques
are to be carried out subsequent to application of heat, the manual
expression should follow immediately, or within about 90
seconds--with shorter intervals being preferred, e.g., within 30
seconds, or in any event, prior to reversal of the effects of the
application of the regulated heat source such that at least a
portion of the occlusion is removed. It will thus be clear from
this graph that prior techniques of using warm compresses may be
substantially less effective if manual expression does not follow
within an extremely short period of time. Moreover, if the
compresses cool below a therapeutic level prior to manual
expression, they may provide minimal benefit to a patient suffering
from substantial obstruction.
[0081] It has been discovered that the problem with most
pharmacological treatment modalities for dry eye syndrome is that
the pharmacological agent is unable to affect MGD when the disorder
involves obstructions of the gland. That is, the currently known
pharmaceutical treatments simply cannot unclog the meibomian glands
to permit flow of lipids. While antibiotic treatment, steroid
treatment, or other pharmacological treatments may be useful for
other causes of dry eye, they have been found ineffective (or at
most, to provide temporary symptomatic relief) when obstruction of
the meibomian glands is involved. While many pharmacological agents
may be useful in promoting lipid production and flow of the
meibomian glands, such lipid production is not effective, and may
be counterproductive if the secretion cannot get out of the gland.
In fact, promoting lipid production may cause more meibomian
difficulties and inflammation of the glands.
[0082] Other pharmacological agents may assist in promoting tear
production or otherwise assisting in the lubricating function of
the eye by promoting an improvement in the tear film. Used alone,
such treatments may be ineffective or only partially effective,
whereas, used after clearing of the meibomian glands may restore
normal or near normal production of all components of the tear
film. Hence, many pharmacological agents may be appropriate for
further enhancement of the tear film and may be extremely
beneficial once the meibomian glands are returned to more normal
function.
[0083] Hence, once flow has been restored to the meibomian glands
by heat and manual treatment (e.g., pressure during or after
treatment, vibration, pulsation, manual expression, etc.),
treatment with various pharmacological agents can be beneficial to
maintaining the flow of lipids from the glands. Hence, with
reference to FIG. 5, a treatment regimen is described starting at
100, after which a controlled heat such as produced by the various
apparatus described in the above-referenced and incorporated by
reference patent applications is applied to the eyelids at 104. The
preferred heat is greater than 37 degrees Celsius, with a preferred
range of heat between approximately 44-47 degrees Celsius, with a
target of 45 degrees Celsius. However, greater temperatures Celsius
for shorter periods of time will provide therapeutic benefit, with
the possible side effect of minor skin burns that do not cause
lasting damage. Below this temperature range, treatment tends to be
less effective or ineffective. Temperatures above this range can
cause substantial patient discomfort, injury to the eyelids and
possibly the eye. At higher temperatures within the range, the
patient may find the heat to be somewhat uncomfortable, but the
treatment time can be reduced and the discomfort can be moderated
with anesthetic. Lower temperatures in the range are effective but
generally take a longer heating period.
[0084] As a rule of thumb starting point, fifteen minutes at a
relatively constant 45 degrees generally works well for many
patients with mild to moderate MGD without undue patient
discomfort. Time ranges from about 10-60 minutes or even beyond may
be used depending upon the severity of the MGD condition, the
temperature, anesthetic used and patient tolerance. In experiments,
times beyond one hour were used without apparent adverse
effects.
[0085] Once the heat treatment is completed (and/or during the heat
treatment), mechanical force can be applied at 108 in any of the
above mechanical modalities discussed to express the fluids or
suspensions from the meibomian glands while the obstructions are in
the melted state. When expression of the glands is used, it is
preferable that any instrument used in the expression process be
heated so as to simultaneously apply or assist in maintaining heat
to the glands at the time of expression.
[0086] While manual expression of the gland can be painful and is
invasive with inconsistent results when used alone due to
variations in manual control and/or manipulation, and while this
method of treating MGD can also be quite uncomfortable to the
patient because it requires the physician to squeeze the glands,
this technique may prove useful as a step in the process used
selectively in difficult cases. There are about 45-50 glands
between the upper and lower lid, therefore, it is very time
consuming to squeeze each gland and therefore inefficient for the
physician and uncomfortable for the patient to endure. However as
noted, it may be beneficial in combination with automated
expression devices to assist in further clearing severely
obstructed glands to enhance the normal flow of lipids flowing
through the orifices and out of the glands to the tear film. After
heat treatment, the expression of secretions from an obstructed
gland is generally dramatically more effective with less patient
discomfort and better results, than if used alone. As noted
previously, when expression of the glands is used, it is preferable
that any instrument used in the expression process be heated so as
to simultaneously apply heat or assist in maintaining heat to the
glands at the time of expression.
[0087] Once the occlusions and other foreign substances have been
cleared from the meibomian glands at 104 and 108 and lipid flow is
restored, the meibomian glands can be treated with any of a variety
of pharmacological agents, either topical or systemic, in order to
minimize inflammation of the glands, clear infections, prevent
further blockages, thin the lipids, promote production of tears,
enhance the composition of the tear film, or any other
pharmacological modality that promotes the free flow of the lipids
or enhanced lubrication of the eye at 112. Pharmacological
treatment may be carried out either for a short duration (e.g., to
clear an infection or inflammatory condition), or for ongoing
therapy (e.g., as in pharmacological agents that thin the lipids,
reduce inflammation or treat other modalities of dry eye syndrome).
This process ends at 116.
[0088] Many pharmacological agents have been proposed for treatment
of dry eye syndrome, any of which may be effective or more
effective upon clearing of obstructions within the meibomian
glands. Some of the pharmacological agents that may be utilized
include, but are not limited to: antibiotics such as topical or
oral tetracycline and chemically modified tetracycline,
testosterone, topical or oral corticosteroids; topical androgens or
androgen analogues, omega 3 fatty acid compounds such as fish oils,
laennec, enzymes that promote lipid production, agents that
stimulate production of enzymes that promote lipid production, and
any agent which acts as a secretagogue to enhance meibomian gland
secretion or secretion of other tear components. Androgen and
androgen analogues and TGF-.beta. have been reported to act as a
secretagogue to enhance meibomian gland secretion, agents that
replace or promote production of any tear component, and there are
likely many others. These compounds are illustrative examples of
appropriate pharmacological agents, but those skilled in the art
will appreciate that other pharmacological compounds may be
utilized upon consideration of the present teachings. It is further
noted that multiple modalities may be involved in causing dry eye
syndrome, but treatment of only one modality may not result in full
resolution. Hence, the restoration of normal or near normal lipid
flow from the meibomian glands may be only a part of the
solution--with pharmacological treatment of the other modality or
modalities of the disease restoring a normal tear film. However,
when significant MG dysfunction is involved, treatment of the other
modalities alone is likely to be less than satisfactory.
[0089] A variation of the above treatment is described in
connection with FIG. 6 starting at 130, after which a controlled
heat such as produced by the various apparatus described in the
above-referenced and incorporated by reference patent applications
is applied to the eyelids at 104 as in the prior treatment method.
The preferred range of such heat is again between approximately
44-47 degrees Celsius, with a target of 45 degrees Celsius. Again,
time ranges from about 10 to 60 minutes and beyond may be used,
depending upon severity of the condition, the treatment temperature
and patient tolerance.
[0090] In this embodiment, during the heat treatment, mechanical
force can be applied at 138 in any of the above mechanical
modalities discussed, including those referenced and incorporated
by reference, to express the fluids or suspensions from the
meibomian glands while the obstructions are in a liquid or
suspension state during application of the heat.
[0091] Depending upon the patient response to heat in combination
with simultaneous mechanical force at 138, additional force can be
applied immediately subsequent to removal of the heat at 142. In
this case, it is also preferred that heat be maintained during the
time of expression or force being applied as described. That is, it
is preferred that any probe or other instrument used during the
expression be heated to help maintain the obstruction in a liquid
or suspension state. Such force can be manually applied by
squeezing the eyelids at appropriate locations where obstructions
appear to remain, or automated mechanical means may be employed if
available.
[0092] Once the occlusions and foreign substances have been cleared
from some or all of the meibomian glands at 104, 138 and 142, the
meibomian glands can be treated with any of a variety of
pharmacological agents, either topical or systemic, in order to
minimize inflammation of the glands, clear infections, prevent
further blockages, thin the lipids or any other pharmacological
modality that promotes the free flow of the lipids or otherwise
promote an improved tear film at 112 as before. As noted,
pharmacological treatment may be carried out either for a short
duration (e.g., to clear an infection or inflammatory condition),
or for ongoing therapy (e.g., as in pharmacological agents that
thin the lipids, improve the tear composition, or reduce
inflammation). This process ends at 150.
[0093] The above processes, whether involving the process of FIG. 5
or FIG. 6, may be repeated or interchanged at time intervals as
needed to create or maintain proper flow from the meibomian glands.
Such treatments, or portions thereof, may need to be periodically
repeated for some patients in order to keep the lipids flowing from
the meibomian glands.
[0094] Thus, in accordance with certain embodiments consistent with
the present invention, a method of treating mammalian meibomian
glands involves clearing the glands by applying a regulated heat to
an eyelid containing the meibomian glands to reach a temperature
adequate to melt obstructions in the meibomian glands and
maintaining the heat for a time period adequate to melt the
obstructions and place the obstructions in a fluid or suspension
(melted) state. The glands can then be mechanically treated to
express fluid or suspension from the glands, wherein the mechanical
treatment is carried out either during the time period or after the
time period but while the obstruction remains in the melted state.
The process may be enhanced by a heated treatment device for
applying the force to maintain the temperature and the melted state
of the obstructive material. Subsequent pharmacological treatment
of the glands by use of a pharmacological agent (topical or
systemic) can then be used to assist in maintaining proper flow of
lipids from the glands.
[0095] In accordance with certain embodiments, the time period can
be approximately 10 to 60 minutes, and approximately 15 minutes is
generally suitable for mild to moderate cases. The temperature
should be greater than 37 degrees Celsius and the preferred range
is approximately 44 to 47 degrees Celsius with a target of 45
degrees Celsius at the eyelid's outer surface has been found
effective and comfortable to the patient. In certain embodiments,
the mechanical treating is carried out as soon as possible after
the heating, and preferably within about 30-90 seconds, so that the
obstruction will remain in a melted state during the expression
process. In other embodiments, the mechanical treatment is carried
out by at least one of application of constant pressure, squeezing,
milkingly expressing the fluid or suspension from one or more of
the glands while simultaneously applying heat, or applying
vibratory stimulation to the eyelid while simultaneously applying
heat. Many variations and alternative embodiments will occur to
those skilled in the art upon consideration of the present
teaching.
[0096] An apparatus for unplugging the obstructed gland channel C
is schematically illustrated in FIG. 7A. The apparatus comprises a
power source 160 which may be direct current (battery powered) or
alternating current (wall socket) as desired. The power source 160
is connected to a controller, generally indicated at 200, which
includes a power on/power off switch 210. The controller 200
includes a means 220 for applying an external force to the gland to
loosen the obstruction. The means 220 includes a probe 230, which
is adapted to vibrate at a preselected frequency at preselected
amplitude. The probe 230 may vibrate at sonic or ultrasonic
frequencies as needed. In addition, means for varying the frequency
240 and amplitude 250 of the probe output, well known to those
skilled in the art, are provided. The means 220 for applying the
regulated external force or regulated energy to the obstruction may
also include fluid jet, air fluid, water fluid, microwave energy,
needles, micro-needles, laser energy, RF energy, aspiration,
suction, vacuum, pressure, piezoelectric, and compression.
[0097] Turning now to FIG. 7B, a small ultrasonic probe 230 (and
specifically the probe tip) is illustrated in FIG. 8C in place on
the eyelid. The probe 230 is adapted to deliver ultrasonic
vibrational energy through the skin into the obstruction P in order
to loosen, liquefy, and/or fracture the obstruction. More
specifically, by tuning the probe output so that the obstruction P
resonates (by adjusting the frequency and amplitude of the signal)
energy is efficiently transferred to the obstruction and
sympathetic vibration of the obstruction P occurs with minimal
energy transfer to the surrounding tissues. In some instances,
vibration alone may be sufficient to change the characteristics of
the obstruction P such that vigorous blinking may express the
obstruction remnants.
[0098] In addition to vibration alternative force, energy,
aspiration and/or chemical/pharmacological agents can be used to
open up the channel C. The probe may be further equipped with
aspiration means 260 (best illustrated in FIG. 8C for introducing
aspiration, suction or vacuum into the gland channel C to evacuate
the obstruction remnants. Alternatively, heat and aspiration may be
employed in lieu of or in addition vibration.
[0099] In another aspect of the invention, the probe 230 may be
equipped with a means for heating 270 such as a solid state heating
element which may be regulated to provide relatively precise
amounts of energy in the previously mentioned ranges that assists
in softening, liquifying or melting the obstruction P via heat
transfer through the tissue when the probe is placed against the
tissue.
[0100] A second embodiment of the invention (FIG. 9) employs
microdermabraision or exfoliation to remove any cells or cellular
material that may have overgrown the gland opening.
Microdermabraision is a process that was developed for use in
dermatology to remove dead skin cells. As shown in FIG. 9 a probe
or tip 330 is equipped with an abrasive surface 310 that is adapted
to scrape the skin. The abrasive employed is usually a diamond
power or other suitable material, well known to those skilled in
the art. An inner tube 320 having a central bore 325 includes holes
defining openings 330 through which a fluid such as air is pumped.
An outer covering 335 surrounds the tube 320, but at its lower edge
extends slightly lower and is spaced from the abrasive surface 310
and a space is defined between the lower ends of the respective
tubes 320, 335. The outer covering is connected to aspiration,
vacuum, and/or suction that operates as described herein below.
[0101] In operation, the clinician would place the abrasive tip 310
in contact over the gland orifice creating a seal between the tip
and the skin. Movement of the probe 330 would cause the abrasive
310 on the bottom of the tip to separate the cells from the skin
and the aspiration, suction or vacuum would extract the cellular
material from the vicinity of the gland opening. In addition,
depending upon the obstruction, aspiration, suction and/or vacuum
alone may be sufficient to extract the obstruction.
[0102] Additional features may also be providing to the
microdermabraision tip such as a heating element 340 which could be
placed in the outer covering 335 near the tip. In addition, the
inner tube 320 could be equipped such that ultrasonic energy could
be delivered to the obstruction as discussed herein above.
[0103] Another embodiment of the invention may employ a chemical
agent to clean the gland margin and to remove or exfoliate cells
from the meibomian gland orifice. For example Ophthaine.RTM. or a
similar pharmacological agent may be employed to assist in removing
epithelial cells from over the gland orifice. A probe similar to
that shown in FIG. 9 may be employed, except that the inner tube
will deliver the chemical agent and the suction applied by the
outer covering will be used to evacuate the used chemical agent and
cellular material mixture away from the gland margin. Similarly,
the heating and vibrational features discussed above may also be
included.
[0104] A further embodiment of the invention may deliver
vibrational and/or thermal energy to the obstruction P without
contacting the gland. One potential energy source is laser light
supplied by titanium, argon, krypton or microwave energy.
Extraction of the obstruction would be accomplished by the means
described herein above.
[0105] A third embodiment of the invention employs pressure applied
to the tissue as shown in FIGS. 10A, 10B, and 11 by rollers (or
drums) 375 which are placed in front of and/or behind the meibomian
gland with the rollers applying constant regulated pressure to the
meibomian glands to apply a "milking" type force to expel the
obstruction to return the gland to normal secretion levels. The
rollers can be connected to heat, aspiration, vacuum, and/or
suction that operate as described herein.
[0106] In operation, the physician would place the rollers 375 in
contact with the eyelid, either inside, outside or both. Lateral
movement of the rollers 375 would cause pressure to be applied to
the gland to remove the obstruction. Alternatively, aspiration,
suction and/or vacuum could be applied to extract the obstruction
and material from the vicinity of the gland opening. In addition,
depending upon the obstruction, aspiration, suction and/or vacuum
alone may be sufficient to extract the obstruction.
[0107] Additional features may also be provided to the rollers such
as a regulated heating element (not shown) which could be placed in
the outer covering near the tip as shown in FIG. 10A. In addition,
the roller 375 could be equipped such that ultrasonic energy could
be delivered to the obstruction as discussed herein above.
[0108] FIG. 12 illustrates a prototype hand held suction system
generally indicated at 400 that was constructed. The system
comprised an AC power supply 410 which powered a suction pump 420
to which tubing 430 was connected. At the opposite end of tubing
430 a probe 440 was connected. A tip 450 having a 1 mm diameter and
a 200 micron orifice was attached to the end of the probe 440. The
probe end 460 was curved for ergonomic access to the gland orifice.
In use, the tip 450 is placed on or proximate the gland orifice and
the applied vacuum is used to collect the obstruction as it exits
the orifice or may alternatively be employed to assist in
expression of the obstruction.
[0109] FIG. 13 illustrates another prototype of a hand held
apparatus generally indicated at 500 that was constructed. The
system comprised a power supply 510 which powered an electromagnet
(not shown) which was encased in a handle 530 that may be easily
held by the clinician in one hand. A rod 540 is mounted for
reciprocating motion to the output of the electromagnet. The throw
or amount of movement of the rod 540 is 0.5 mm. At the end of rod
540 is mounted a back plate 550 which is substantially
perpendicular to the axis of rod 540. Further, a lever 560 is
pivotally mounted to rod 540 and operates to actuate a roller 570.
A heating means or heater 580 was mounted in backplate 550. The
heater 580 was also provided with an appropriate power source. In
operation, the device is positioned such that the back plate 550 is
positioned between the cornea and the back surface of the eye lid.
The lever 560 is actuated such that the roller 570 comes into
contact with the front surface of the eye lid. The arc of the
roller is such that the eye lid is squeezed between the foregoing
The clinician may elect to maintain the back plate and the roller
under tension for a preselected period of time to soften the
obstruction. Once the desired temperature has been reached, further
pressure on the lever 560 will cause the roller to move from the
bottom of the meibomian gland (the end away from the orifice) to
the top of the gland to express the obstruction from the gland in a
"milking type" motion. Thus, a repeatable regulated method for
opening obstructed meibomian glands is provided.
[0110] The embodiment illustrated in FIGS. 14A through 14C, the
present invention prototype is a hand held apparatus generally
indicated at 600. The apparatus comprises a power source 610 which
may be a DC source such as a battery or an AC source similar to
those discussed herein above. The power source 610 resides within a
housing 620. The power source 610 provides electrical current to a
wave form generator 625 which powers an acoustic amplifier 630 (for
example, a small audio speaker) also located within housing 620 and
mounted at an ergonomic angle therein. The acoustic amplifier 630
is programmed to vibrate in a wave format at a frequency of 0 to
200 Hz at an amplitude in the range of 0.25 mm to 5 mm. Initial
experiments indicate that free air amplitude of 3-4 mm at a
frequency of 60 Hz to 125 Hz is well tolerated and after 10-30
seconds of application seems to impart a natural numbing effect to
the eyelid/gland. Mounted in operative association atop the
acoustic amplifier 630 is an annulus 635 that floats thereon and
includes a cone shaped housing 640 extending perpendicularly away
from the amplifier 625 that encloses the amplifier 625 The end of
the housing 640 is adapted to mount a variety of tips 650. For
example, the tip may comprise a roller 655 mounted for rotation in
a cradle 665. Further, the tip 650 may be modified to include a
regulated heating element (not shown) that acts to soften the
obstruction. Other tip configurations may include a vacuum for
collecting the obstruction after expression thereof from the gland
and different tip configurations to apply various contact areas and
resulting forces. Thus, it will be seen that the obstruction is
actually subjected to a pair of forces, the first being the weight
of the device itself on the gland which may be combined with
additional pressure by the health care provider pressing on the
gland plus the additional intermittent force delivered to the gland
by the vibratory or pulsatory force of the tip 650. The first force
may be a fixed constantly applied force or one that increases to a
preselected maximum. Testing has indicated that use of the
foregoing method, i.e., applying a first force to the meibomian
gland and a second pulsatile force to the meibomian gland allows
delivery of a greater quantity of energy to the obstruction while
lowering the perceived pain level to the patient. It is believed
that this is the result of an overall lower degree of localized
nerve stimulation about the orbit. Heating the gland is also
beneficial in the event softening of the obstruction is needed
prior to expression thereof.
[0111] Another embodiment of the invention is shown in FIGS. 15A
through 15E wherein the treatment apparatus is incorporated into a
goggle-like device, termed herein as the "hydro-oculator" which is
a head borne device that locates the treatment mechanism proximate
the eyelids, generally indicated at 700. The hydro-oculator 700
comprises a flexible frame 705 having a headband 710 (which may be
elastic) connected thereto at each end. Connected to the bottom of
the frame 705 is a molded housing 720 which has an angled leg 725
which is adapted to overlie the cheek bone when the apparatus is in
use. Further, an expandable fluid or gas impermeable container
referred to herein as a bladder 730 is positioned within the cavity
defined by the space between the housing and the lower eye lid. A
pumping mechanism is provided that facilitates movement of a fluid
or gas, collectively referred to herein as a "medium" (not shown)
into and out of each of the respective bladders 730. According to
the invention, the patient would position the hydo-oclulator 700 on
his or her head such that the leg 725 of molded housing 730 rests
on the upper cheek bone as best shown in FIGS. 15C through 15E. The
regulated heated medium is pumped into the bladders 730 causing
partial expansion thereof in order to apply a pressure to the
eyelids in the range of from zero to fifty pounds per square inch
(50 psi). The bladder containing the heated medium (a water based
solution being preferred) is positioned on the eyelids over the
meibomian glands for a preselected period of time (up to thirty
minutes) to soften the obstruction. It is desirable to place the
heat source in direct contact with the eyelids which thereby
transmits thermal energy to the meibomian glands, in contrast to
the prior art which heats a confined space in front of the open eye
where heat could be transmitted to the ocular bulbi structures such
as the crystalline lens which introduces the possibility of
cataract formation. Thereafter, the bladder is slowly expanded to a
preselected maximum such that the force on the gland increases from
the bottom up to the top or orifice end of the gland such that the
obstruction is expressed therefrom in a "milking" type of action.
Milking may be applied at a preselected frequency between zero and
five hertz (0-5 Hz) and for a preselected period of time, usually
not more than thirty minutes. In addition, the medium may be
"pulsed", i.e., milkingly moved into and out of the bladder to
further facilitate expression of the obstruction from the gland.
Pulsing may also be achieved by providing an external force to the
bladder and transmitting the force through the fluid into the
gland. Pulsing may be applied at a preselected frequency between
zero and one hundred hertz (0-100 Hz) for a preselected period
time, usually not more than thirty (30) minutes. A chemical or
pharmacological agent may be inserted into the meibomian gland to
assist in softening the obstruction and any of the extraction
modalities mentioned above may be further employed to assist in
removing the obstruction.
[0112] Another embodiment of the invention may employ a chemical
agent or compound to clean the glandular margin to remove or
exfoliate cells from the gland orifice. A probe similar to that
shown in FIG. 9 may be employed, except that the outer drum or
roller will deliver the chemical agent and the suction applied by
the outer covering will be used to evacuate the used chemical agent
and cellular material mixture away from the gland margin.
Similarly, the heating and vibrational features discussed above may
also be included.
[0113] A further embodiment of the invention may deliver
vibrational and/or thermal energy to the obstruction P without
contacting the gland. One potential energy source is laser light
supplied by a titanium-sapphire, argon, krypton, RF energy or
microwave energy. Extraction of the obstruction would be
accomplished by the means described herein above.
[0114] Another embodiment of the invention employs the use of
chemical or pharmacological agents to open or dilate the gland and
gland orifice wherein the obstruction naturally is expressed and
returns the normal secretions of the gland. Alternatively, the
chemical or pharmaceutical agent would be used to soften or breakup
the obstruction with such obstruction being expressed with the use
of devices as defined above or combinations thereof. Chemical or
pharmacological agents may also be used in connection with the
device for post treatment. Once the glands have been opened then
chemical or pharmacological agents may be used to enhance the
normal production or secretion to maintain the glands in its
unblocked state.
[0115] Dilation of the meibomian gland channel and orifice may also
be employed to loosen or free the obstruction from the gland walls.
Dilation may be accomplished by chemical, pharmacological, or
mechanical means.
[0116] Stimulation of the meibomian gland may also be employed in
conjunction with the other modalities discussed above to loosen or
fracture the obstruction.
[0117] While certain illustrative embodiments have been described,
it is evident that many alternatives, modifications, permutations
and variations will become apparent to those skilled in the art in
light of the foregoing description.
* * * * *