Giving Sight to the Blind

Scientists working on cures for blindness tend to focus on the obvious tar-get--the eye. That's what researchers at Johns Hopkins, whose computer-chip-in-the-eye treatment raised Stevie Wonder's hope of seeing, did. But such chips promise to help only people whose blindness results from damage to the retina. This week, biophysicist William Dobelle of the Dobelle Institute in New York reports, in ASAIO Journal, a system to help any of the 1.1 million Americans who are legally blind, regardless of the cause. A mini-camera mounted on sunglasses captures images that are processed by a 10-pound computer; the signals then run through a cable to 68 electrodes implanted in the visual cortex. The electrodes stimulate the brain, producing an array of bright spots good enough for 20/400 vision--and for navigating sidewalks. Dobelle plans to make it commercially available this year. The expected price if the procedure becomes routine: $50,000. More than a Seeing Eye dog (some $40,000), but electrodes don't eat.