New surgery and headset may boost vision.

A surgical technique may one day benefit people suffering from a blinding eye disease known as macular degeneration, according to a preliminary study of monkeys. If that approach doesn't work, another might: Researchers are working on a futuristic headset that would help people with impaired vision see the world on a personal television-like monitor.

Henry J. Kaplan and his colleagues at the Washington University School of Medicine in St. Louis wanted to find a way to correct age-related macular degeneration. In the so-called wet form of this disease, an abnormal growth of leaky blood vessels leads to injury of the macula -- the center ofthe retina that distinguishes details. This process, which usually strikes older people, gradually causes blurring of central vision and, in severe cases, blindness.

Kaplan's team began by operating on three healthy macaque monkeys. First, the surgeons made an incision in the retina. Then they used a pair of small, tweezer-like instruments to remove retinal pigment epithelial cells, the part of the macula damaged by scar tissue.

One hour after surgery, they sacrificed and examined one of the monkeys. As expected, they found a bare spot where they had removed part of the retina. However, three weeks later, they found the beginnings of a repair process in a second monkey. Nine months later, examination of the third monkey revealed new retinal pigment epithelial growth in areas that had been stripped during the operation. In addition, photoreceptor cells that had been disrupted by surgery had healed, suggesting that the blurry vision caused by the surgery had improved. Kaplan described the new findings last week at the annual meeting of the Association for Research in Vision and Ophthalmology, held in Sarasota, Fla.

While the surgeons couldn't test the monkey's vision, they did make another surprising observation at about the same time. An 80-year-old woman with macular degeneration, who had received a similar experimental operation at Washington University, came in for a checkup. Just before surgery, she had 20/400 vision, which made her legally blind in one eye. To make sure her vision didn't get any worse, Kaplan's group removed the scar-damaged retinal pigment epithelial cells. About a year later, her vision had improved to 20/60.

Kaplan believes the same repair process observed in the monkeys helped the woman see better, although he admits that further studies with a large number of human patients are needed to test this theory. Lee Jampol, a retinal expert at Northwestern University Medical School in Chicago, warns against jumping to conclusions based on a very preliminary monkey study. "So far, this is not a wonder procedure," Jampol says. "It's not going to mean the end of macular degeneration," he adds, noting that other researchers have tried a similar technique on human patients, with disappointing results so far.

Surgery isn't the only approach. This week, scientists at NASA and the Wilmer Eye Institute of John Hopkins University in Baltimore unveiled a prototype device that may one day help people suffering from macular degeneration or other eye disorders. More than 80 percent of people who are legally blind retain some vision and would be candidates for the new device, the researchers note.

Using computer technology developed by NASA for processing satellite images, the scientists designed a device that looks like a wraparound headset. A tiny camera mounted on the device records the scene in front of the wearer and displays it on two video screens, says Robert W. Massof, director of the Wilmer Eye Institute. By turning a knob on the headset, the wearer can adjust the contrast of the video image or magnify it.

"A large part of the consumer market for this will be senior citizens," Massof says. "The number of senior citizens is growing, and many of them will develop vision problems that this device will solve."

While the new headset is expected to be available within the next 18 months, a more ambitious device is expected to remain in the laboratory for a few more years. In that version, the headset is connected to a computer that corrects for the patient's visual defect and then displays the corrected image on the video screens, says Doug Rickman, low-vision project manager at NASA's Stennis Space Center in Mississippi. Rickman has tested such a device in the laboratory, but since it relies on a massive supercomputer, a portable version may take five years to develop, he says.