by Poppy Sundeen

According to a national survey, blindness is the disability people dread most. It’s a fear that all too often turns into reality for the 11 million Americans who suffer from macular degeneration.

Soon those numbers are expected to rise as macular degeneration, the leading cause of blindness among Americans ages 55 and older, hits the baby boom generation. For that reason, Carl Kupfer, M.D., formerly of the National Institutes of Health, expects macular degeneration to reach epidemic proportions in the years to come.

But along with the grim projections comes hope in the form of experimental treatments for macular degeneration.

Currently, studies are under way to evaluate new treatment options for macular degeneration patients. Several of the clinical trials are taking place right here in Arlington at Texas Retina Associates.

Wayne Solley, M.D., a vitreoretinal disease specialist on the staff of Arlington Memorial, is one of Texas Retina Associates’ partner physicians.“My interest in research goes back to my ophthalmology residency and fellowship at Emory University,” says Dr. Solley. “My partners and I have maintained our relationships with academic institutions and welcomed opportunities to participate in clinical trials.We’re one of a relatively small number of private practices involved in this kind of research.”

Among the clinical trials under way at Texas Retina Associates are a number of studies involving “wet”macular degeneration. Actually, dry is the more common form of macular degeneration,” Dr. Solley notes. Unfortunately, there’s been no real treatment progress on that front. The good news is that we have new hopes for treating wet macular degeneration, the form that brings about the most rapid and profound vision loss.”

Macular degeneration is the deterioration of a part of the retina known as the macula. The macula is located in the central portion of the retina and is critical to the central vision required for reading, driving and recognizing objects. As macular degeneration progresses, patients have increasing difficulty seeing whatever is directly ahead in the center of the visual field.

In the case of wet macular degeneration, the damage to the macula is complicated by abnormal blood vessel development under the retina. As the blood vessels grow, they leak, causing swelling and fibrous scar tissue formation. Eventually, the scar tissue damages the eye’s rods and cones, disrupting the transfer of visual information from the eye to the brain.

Currently, the most widely used treatment for wet macular degeneration is photodynamic therapy, a procedure Dr. Solley performs at his office on the Arlington Memorial campus. Dye-marked fibrous tissue is treated with a cold laser beam. The treatment has been moderately successful in slowing or stopping visual deterioration. In fact, 15 percent of patients note some degree of improvement.

Two of the trials under way at Texas Retina Associates involve injections with a new product developed by Genentech. “It’s an antibody fragment that works by binding a specific kind of growth hormone in the eye,” Dr. Solley explains. “The antibody impedes the hormone’s function, so the abnormal blood vessel growth is slowed or stopped. As the blood vessels become less active, the leakage subsides along with the swelling and scar tissue formation.”

In one of the two studies, patients receive injections of the Genentech product as their sole treatment. The other study uses the Genentech product in concert with photodynamic therapy. The studies are scheduled for completion in 2005.

“The Genentech product is just one of several new treatments under evaluation,” says Dr. Solley. “Of course, we always hope for a home run,” he adds, “but even when we don’t have an overwhelming success, we gain knowledge — knowledge that could lead to yet another promising discovery.”