discovering dry eye

The Future of Dry Eye Treatments

BY BARBARA CAFFERY, OD
DECEMBER 1999

Because the treatments currently available for all levels of dry eye are insufficient, managing dry eye patients can be severely frustrating. The chronic discomfort and pain is poorly understood, and rather than trying to change the main cause of the pain, practitioners are attempting to utilize palliative treatments. The research community is making every effort to change the status quo and their proposals sound exciting. Two main areas of treatment now being tested are topical anti-inflammatories and topical hormones.

Anti-inflammatory Treatments

Allergan Pharmaceuticals has been experimenting with using topical cyclosporine to treat dry eye. Cyclosporine is an anti-rejection drug that is used systemically in transplant patients. It reduces inflammation by a different mechanism than steroids and is not associated with glaucoma or cataracts. This drug may work on the lacrimal gland, and has been shown to change the internal inflammatory activity of the conjunctival epithelium.

The concept of using topical anti-inflammatories was pioneered by Stephen Pfluegfelder, M.D., and his research team in Miami. Pfluegfelder and his colleagues used low dose topical steroids in dry eye patients and found positive results. Many patients experienced a reduction of symptoms and their ocular surfaces appeared healthier with reductions in staining. Although the side effects of long-term steroid use in the eye prevent this treatment from becoming commonplace, the effort has prompted others to pursue the use of anti-inflammatories.

By looking at the pathophysiology of two known causes of dry eye, we can better understand the proposed methodology of treatment. Because the lacrimal gland is invaded by inflammatory cells in Sj�gren's Syndrome and in senile degeneration, the use of these topical agents is relevant. In more common dry eye states, the poor quality tear film may induce a secondary inflammatory response in the epithelium of the conjunctiva and cornea, which may be what is affected by the topical steroids.

Trial by Hormone

Hormones affect the eye in many ways. In the past, topical estrogen has been used on dry eye patients in research done by Virginia Lubkin, M.D., in New York in 1995. Her hope was that topical estrogen would increase the wetness of the ocular surface. Unfortunately, the ointment only helped for up to three months and then wore off.

New research at UCLA in California and at Harvard University in Boston has demonstrated the strong association of testosterone with the lacrimal gland and the flow of the meibomian glands. Lacrimal gland dysfunction in dry eye disease may be related to a relative shortage of testosterone at the level of the lacrimal gland. Therefore, topical testosterone is now being researched at the clinical level to determine its effect on these surface structures.

As we struggle to maintain the ocular comfort of our dry eye patients, other professionals in the industry are working diligently to develop treatments that will change the course of this disease, and perhaps even eradicate it.

Dr. Caffery has practiced optometry in Toronto, Canada, in a group setting dedicated to contact lens and tear film research since 1977.