DRY EYE UPDATE
DRY EYE UPDATE
Part I of this two-part series
highlights new research and products.
By Barbara Caffery, O.D. Toronto, Canada
As eyecare practitioners, you
probably know that an estimated 59 million Americans suffer from
dry eye. You're also most likely aware that dry eye syndrome has
many causes, ranging from the normal aging process to
environmental conditions to computer work and contact lens wear.
In fact, because so many people experience dry eye symptoms and
because so many factors come into play with this syndrome, it's
one of the most common problems you treat.
With this in mind, it's only
logical that you need to become aware of all the treatment
options available. In this update, we'll let you know what's
going on around you in the area of dry eye. First we'll take a
look at some areas of research from the past year, then we'll
review some of the newer products on the market.
We'll come back again in April
with Part II, which will include punctal occlusion questions
answered by an expert, an interesting proposed method to treat
dry eye, highlights from the first clinical conference on Sj�gren's
syndrome and much more.
Dry Eye Research
A look at some exciting new
research from the past year.
Dry eye is an area of interest for
a growing number of researchers. Let's look at some of the more
interesting research findings reported in 2000.
Although many of these concepts
are unproven, it's important to keep abreast of the latest
thinking in this area. They'll change our concepts of many
diseases and improve our treatment tactics.
- The neurological
control of conjunctival goblet cells in rats.
Darlene Dartt, Ph.D., presented this paper at last year's
Association for Research in Vision and Ophthalmology (ARVO)
meeting. Goblet cells manufacture mucin sacs that travel
to the cell membrane and explode into the tear film,
releasing all the granules from the cell. Dr. Dartt
explored the role of the nervous system in controlling
goblet cell function. She theorized that when the cornea
is irritated by dry eye, sensory information to the
central nervous system produces efferent messages to the
ocular surface goblet cells in a form of feedback loop.
Dr. Dartt demonstrated the proximity of muscarinic and
vasoactive intestinal peptide (VIP), parasympathetic
nerve endings around the goblet cells of the rat.
In normal states, minimal stimulation of the cornea and
conjunctiva produces mild parasympathetic stimuli for
regular goblet cell secretions. Corneal damage associated
with severe or prolonged dry eye results in decreased
With lessened stimulation, the eyes become drier, which
causes more damage and further reduced sensitivity.
Severe Sj�gren's syndrome is an example of this extreme.
Also, with giant papillary conjunctivitis (GPC), the
cornea is continually irritated, which in turn causes
more mucus secretion.
- A lacrimal gland
and tear film conference was held in Hawaii in November.
The Dry Eye Investigations (DREI) group reported on their
research questioning subjects about their ocular surface
symptoms. They asked the volunteers, "When it comes
to the feelings on the surface of your eye, what do you
feel, how badly do you feel it and when do you feel it
The most common feeling of both contact lens wearers and
non-wearers was discomfort. Contact lens wearers felt the
symptom of dryness more often and more intensely than the
non-lens wearers. Most subjects with symptoms felt the
sensations more intensely in the evening.
This diurnal variation is important for clinicians to
note as they may wish to see their patients later in the
day or ask them about their symptoms later in the day to
weed out those who have true dry eye.
- At last year's
ARVO meeting, Michael Stern, Ph.D., of Allergan
Pharmaceuticals, described dry eye disease as a local
inflammatory process. Levels of androgens,
steroid hormones that protect the ocular surface from
inflammation, decrease with age. When the level is
reduced as in menopause, ocular cells make more cytokines
that attract T cells to the conjunctiva, producing
surface damage and increased symptoms of dry eye disease.
Dysfunction occurs in the salivary and lacrimal glands
early in Sj�gren's syndrome. Programmed cell death
occurs, allowing an influx of lymphocytes into these
glands, resulting in damage and reduced function.
- Also at last year's
ARVO meeting, Stephen Pfluegfelder, M.D., discussed
inflammatory changes on the ocular surfaces of dry eye
patients. Compounds in normal tear film,
including lactoferrin, TLMP IL-1 and TGBF, reduce
inflammation. Lactoferrin was significantly reduced in
the tear film of Sjogren's syndrome subjects.
- Restasis study.
Another lecture at ARVO discussed the use of cyclosporin
as a topical anti-inflammatory in dry eye disease. Using
impression cytology, various inflammatory markers, such
as HLA, CD40 and FAS were found in the cells of the
ocular surface. Treatment with cyclosporin reduced
inflammatory markers and symptoms.
- The European research
results on the Restasis (cyclo-sporine 0.05%)
study showed decreased symptoms and improved
ocular surface conditions in patients using the
topical cyclosporine. Interestingly, the vehicle
alone improved many sit- uations, suggesting that
both the placebo effect and rigorous use of drops
can help many patients.
Final FDA clearance for Restasis awaits
additional information from the manufacturer and
further FDA review because the company needs to
conduct another confirmatory study. Allergan, Inc.,
manufacturer of the drug, is seeking an
indication for the topical treatment of moderate
to severe dry eye.
- Risk factors.
The September 2000 issue of Archives of Ophthalmology
reported the study findings of researchers from the
University of Wisconsin Medical School in Madison. In the
study of 3,703 individuals ages 48 to 91, 534 of them
reported symptoms of dry eye syndrome in the past 3
months or longer.
Current smokers were 82% more likely than nonsmokers to
have dry eyes and former smokers were 22% more likely to
have dry eyes than nonsmokers.
Participants who consumed caffeine, mostly through coffee,
were found to be 25% less likely to have dry eyes. The
researchers noted that compounds known as xanthines (caffeine
is one of them) have been shown to stimulate tear
production when applied topically. However, it's not
known whether ingested caffeine has a similar stimulatory
The study results suggest that several factors, such as
smoking, caffeine use and multivitamin use, could be
studied for preventative or therapeutic efficacy.
Dr. Caffery practices in a
group setting in Toronto, Canada. Her practice is dedicated to
contact lenses and dry eye research.
New Product Overview
Here's a quick look at some of
the new dry eye products that are available and those that are on
Here's a way to help your
patients with moderate to severe dry eyes retain the available
moisture on their eyes. Curtailing the rate of moisture
evaporation is of particular value when the patient lives in arid
or windy areas. EagleVision Moist Eye Moisture Panels can be
fitted to most any configuration of eyewear, between the lens and
frame, to create a moisture chamber around each eye.
For additional information,
contact the company at (800) 222-7584 or visit www.eaglevis.com.
- You know that many
patients suffer from dry eyes following laser vision
correction surgery. Well, ScienceBased Health has
unveiled a new approach to alleviate side effects and
speed healing of post-surgical dry eye. KeraCaps Complex
is an oral nutritional product that combines omega fatty
acids to help restore natural eye moisture and other
specific eye health factors.
KeraCaps Complex is a combination of the formulations
HydroEye and OcularEssentials by ScienceBased Health.
- ScienceBased Health's
HydroEye is a proprietary blend of omega-6 fatty acids,
mucin complex and nutrient cofactors that addresses the
root causes of dry eye syndrome. According to the makers,
HydroEye helps prevent drying and atrophy of the tear
glands while supporting proper tear secretion by
promoting the normal structure and function of the
lacrimal glands, conjunctival goblet cells and the mucin
For additional information on either of these products,
contact ScienceBased Health at (888) 433-4726 or
- Carlson Laboratories, Inc.
has a product called Moistur-Eyes. It contains the
nutrients documented to be helpful in improving tear
quality, including Vitamins A, C, B6
and the essential fatty acids EPA, DHA and GLA.
Call (888) 234-5656 or visit www.carlsonlabs.com for
Touch Scientific, Inc.
manufactures the Touch Tear MicroAssay System, an in-office
method of molecular tear analysis. The information is helpful for
separating dry eye into specific etiologies.
Specific tests include
lactoferrin (reimbursed under CPT code 83520) and IgE (reimbursed
under CPT code 82785) for determining "at risk"
patients for giant papillary conjunctivitis and other allergic
The average test reimbursement
is $25, and it costs you less than $10. The system is designed to
use all future tests, including Gram-positive and negative, HSV
Adenovirus and long-term hypoxia. You can lease it for about $299
For more information, call (919)
872-4445 or visit www.touchscientific.com.
introduced Tears Again Gel-Drops, a lower viscosity alternative
to the company's Tears Again Night & Day Lubricant Gel. It's
the same water-based formula as the Night & Day version, but
the Gel-Drops have half the viscosity. It comes in a 15-ml
dropper bottle and lasts 4 to 6 hours. Patients use one drop in
the morning and one in the evening.
For samples or more
information, call (800) 233-5469 or visit www.ocusoft.com.
In the pipeline
Inspire Pharmaceuticals, Inc.
has initiated the Phase III clinical program for the P2Y (2)
receptor agonist INS365 Ophthalmic for the treatment of dry eye
in the United States.
INS365 Ophthalmic is a small-molecule
drug that stimulates the P2Y (2) receptor, a key mediator of
mucosal-surface hydration and lubrication.
Based on the results from the
Phase II program, the company expects this new approach to
enhance the eye's natural cleansing and protective systems by
stimulating the release of salt, water, mucus and other natural
tear components, providing hydration and lubrication of the
The Phase III program consists
of two pivotal clinical trials designed to enroll a total of
approximately 1,000 patients with dry eye in 60 ophthalmology
Both studies are double-masked
comparisons of two concentrations of INS365 Ophthalmic and a
placebo to evaluate the efficacy of the product on a chronic
basis. Both objective ocular-surface measurements and subjective
assessments have been incorporated into the study design, based
on discussions with the FDA.
The company has target dates
for its new drug, but they aren't set in stone. It hopes to
finish the Phase III program in the first half of 2002 and to
file a new drug application (NDA) in the second half of 2002. It's
also looking to launch INS365 Ophthalmic in mid-2003.
The company has entered into a
development and commercialization alliance with Santen
Pharmaceutical Co. Ltd. for this product.
For more information, call (919)
941-9777 or visit www.inspirepharm.com.
Are you aware that the
periocular skin significantly contributes to the health and
function of the eye and influences a patient's ability to see?
Well, it does. It even acts as a barrier against evaporative tear
loss. Periocular skin care is an important aspect of
comprehensive eye care.
To learn more about this topic,
see this month's continuing education article, "Ophthalmic
Management of the Periocular Skin Leads to Better Patient Care,"
in this month's issue.
Optometric Management, Issue: February 2001