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Seeing straight

Blurred, distorted vision in old age might be able to be arrested

Blurred, distorted vision in old age might be able to be arrested

July 22, 2002|by KEVIN CLAPP

kevinc@herald-mail.com

Ah, sweet vision. The ability to view the beauty of a forest, to put a face with a name, to watch your children grow.

The eyes have it. But for how long?

This is the question an aging population is asking about an affliction almost as inevitable as changing seasons.

Macular degeneration is the name of the disease. If the term sounds foreign, the consequence won't: It results in a gradual loss of sight. And it affects roughly 8.5 million Americans.

"People think they can go blind, which is not true," says John W. Cable Jr., OD (optometrist), with Eye Specialists of Central Pennsylvania in Chambersburg, Pa. "It hurts your vision, no doubt. But people don't go black blind. But (vision) gets blurred, distorted centrally."

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So picture a favorite painting. Now imagine it with a grayish hole burned through the center. This is what macular degeneration does; the peripheral edges of the painting are OK, but the central portion is lost.

With macular degeneration, reading becomes difficult if not impossible. In severe cases, driving is out of the question. Hobbyists accustomed to performing tasks with precision movements, such as painting or model building, are unable to see what they are doing.

The macula is a small area accounting for perhaps 10 percent of the retina. But it allows an individual to see fine details clearly.

Before symptoms can be detected, yellow spots called drusen can form on the macula. An early sign of macular degeneration is when straight lines on a grid appear wavy or distorted. See this and you should go to a doctor.

Macular degeneration can be broken into two subsets:

Dry - Causes a generally slow deterioration to central vision, and sight is not as clear as it could be. According to Cable, 90 percent of all macular degeneration diagnoses are dry.

Wet - More problematic. Blood vessels under the retina grow into a section of the eye where they don't belong, leading to blood leakage that impairs vision. Unlike the gradual vision loss associated with dry macular degeneration, wet can cause a rapid and severe loss of sight.

Cases of wet macular degeneration may be less common, but physicians warn that dry can progress to wet.

"As people are living longer and older we are seeing things that we have never seen," says Martinsburg, W.Va., ophthalmologist Mark Promersberger, M.D. "Statistically, you didn't have enough people living long enough for it to be a big issue. Now Granny's 90 and can't see well enough to get around in the house she's lived in for 50 years."

No one is really sure why macular degeneration happens, says Dara Tash, M.D., an ophthalmologist and retina specialist at Retina Center of Western Maryland in Hagerstown. Some signs point to genetics, others to environment and diet.

According to a 2002 Vision Problems in the U.S. report by Prevent Blindness in America, roughly 1.65 million people ages 50 or older have age-related late-stage macular degeneration. Incidence rates are expected to rise as the nation ages.

For ages 55 and older, Cable recommends yearly eye exams. Depending on the form and severity of macular degeneration, check ups should be scheduled every six months, or more often.

Treatments include using a laser to burn the affected area out of existence. The problem with that treatment is it is non-discriminating and decimates the healthy area of the eye as well.

A newer treatment is called ocular photodynamic therapy - medication is injected that will stick to the blood vessels in the eye. A non-burning laser is then focused on the eye at a frequency that triggers the medication.

Theoretically, the blood vessels will inflame and clot, halting the progress of wet macular degeneration.

"It's still not perfect," Tash says. "It's not a panacea by any stretch but it's an improvement."

Still another treatment involves taking daily megadoses of vitamins, a powerful cocktail consisting of 452 mg of vitamin C; 400 international units (IUs) of vitamin E; 28,640 IUs of vitamin A as beta carotene; 69.6 mg of zinc; and 1.6 mg of copper.

Why?

"Antioxidants," Tash says. "The theory is that the yellow in drusen is fat tissue oxidized and not cleared from the back of the eye."

The thought is that the vitamins will prevent more fat tissue from accumulating.

"It's not going to make it better," Cable says. "It tries to halt and prolong any damaging effects."

Often, lack of understanding leads patients to ask whether new glasses can help their vision.

If only the solution were that simple.

Promersberger and Tash return to the example of a camera. Glasses are used to help focus an image that is already there. In macular degeneration, part of the image has disappeared, and it can be a difficult situation to come to terms with.

"If the film in the camera is bad," Tash says, "no matter how much you try to focus the camera, it's not going to take a good picture."




Eye-yi-yi



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