January / 2004
Your Health

Guard against blindness
by: Jennifer Bonck

January is a time of new beginnings and resolutions, many involving health. It also happens to be Glaucoma Awareness Month.

Glaucoma, the second leading cause of blindness in the United States, is certainly something Americans should consider in evaluating their health. Many may be at risk for the disease simply because they don’t know that they have it.

What is glaucoma?
Glaucoma is a group of diseases typically associated with elevated pressure in the eye. Like blood, the eye has pressure, and when this pressure, termed intraocular pressure, increases to dangerous levels, it damages the optic nerve, which carries visual impulses to the brain. This can result in decreased peripheral vision (what you see at the outside edges) and, eventually, blindness.

Early detection is key
There are no early symptoms of glaucoma, so by the time symptoms develop, the disease may have progressed to a highly serious stage, resulting in vision loss. Because of this, the American Academy of Ophthalmology urges Americans to get an eye exam regularly. The earlier the disease is detected, the earlier it may be treated, and the better the chance that vision will be retained.

Groups at a higher risk for developing glaucoma include African-Americans, senior citizens, diabetics, and people taking steroidal medications for extended periods. Also, anyone with a family history of the disease is at risk.

Diagnosis and treatment
“The best way to prevent vision loss from glaucoma is early diagnosis and treatment. See your ophthalmologist at least every two years for a complete examination, including an intraocular pressure check,” says Sheila Sanders, M.D., associate professor of ophthalmology, University of Kentucky College of Medicine. “People at high risk for glaucoma due to high intraocular pressure, family history, ethnic background, or age may need more frequent visits to the eye doctor.”

A test called a visual field may be performed to detect loss of side vision. This test involves staring straight ahead into a machine and clicking a button when a blinking light in peripheral vision is noticed. The visual field test may be repeated regularly to determine the extent of vision loss.

“Treatment for glaucoma involves decreasing the production of fluid in the eye, increasing fluid drainage, or a combination of the two,” says Sanders. “These treatments will not restore any vision already lost to glaucoma, but may prevent further vision loss.”

Generally, glaucoma is first treated with beta-blocker eye drops, which lower fluid production in the eye. These drops may not be used in people with heart conditions because they can affect heart or lung function. There are other pressure-lowering drops besides beta-blockers, called alpha-2 agonists and prostaglandin analogs. Many of the drugs used for glaucoma interact with common medications. Patients should discuss these issues with both their family physician and ophthalmologist.

“Most cases of glaucoma can be controlled with a single drug or drug combinations, but some patients may require or select surgery,” says Sanders. “About 70 percent of patients need new or extra medications within two years after the start of drug treatment.”

Surgical options
Surgical options include a procedure called trabeculoplasty, in which a laser is used to create tiny holes where the cornea and iris meet, to increase fluid drainage. Another procedure called trabeculectomy creates an artificial drainage area; this procedure is used in cases of advanced glaucoma where there is optic nerve damage and the intraocular pressure continues to soar. A third option is a drainage device, which a surgeon implants in the eye to improve fluid drainage.

Sanders emphasizes that timely detection and treatment are key. “The key to treatment is early diagnosis,” says Sanders. “Vision is a precious gift and we must be vigilant in preserving our sight. Regular eye exams are crucial in retaining vision.”

Jennifer Bonck is an information specialist with the University of Kentucky Chandler Medical Center, Office of Public Relations.