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I Can See Clearly Now... |
Diabetes ran in Bill's family: both of his paternal great-grandparents and his paternal grandfather developed diabetes as adults. For Bill the onset of the disease occurred before he was 3 years old. At the age of 8, he took over administering his own insulin shots, beginning a lifetime of strict adherence to a routine vital to his health. This discipline probably delayed the onset of diabetic retinopathy, the insidious and vision-threatening complication that affects nearly all patients with younger-onset diabetes, by the age of 15 or 20. Bill didn't have vision problems until he was about 30, and because he had regular eye exams, doctors caught it early. Laser photocoagulation--making a number of small laser burns around the periphery of the retina--sealed off the abnormal blood vessel growth that can lead to blindness if left untreated. In 1992 Bill had the surgery on both eyes, a procedure that can be done in a doctor's office simply by beaming laser light through the dilated pupil. "I go in four times a year now," Bill reported a few years later, adding that his doctors are very pleased with the results.
In the fall of 1997, a 57-year-old entrepreneur named John woke up one morning seeing flashes of light and spots, or floaters, in front of his eyes. When they persisted the next day, he went to an ophthalmologist, who diagnosed the problem as posterior vitreous detachment and a small retinal tear. The vitreous, a clear, jelly-like fluid that fills the inside of the eye, tends to degenerate during middle age, shrinking and pulling away from the retina. This detachment is common in nearsighted people; John had worn glasses for nearsightedness since the age of 13. Occasionally, the retina is torn when the vitreous pulls away, causing a small amount of bleeding that appears as a sudden onset of floaters. To prevent the tear in John's retina from developing into a retinal detachment, the doctor used a laser to seal it--in effect, spot welding the tear. The procedure took only minutes.
The ease and brevity of these two operations underscore the revolution that lasers have brought to the field of eye care. As recently as the 1950s, almost any eye surgery required a patient to be bedridden for weeks. Today, thousands of people each year have their vision restored or sharpened in procedures that are often virtually painless, owing to the laser's precision and the fact that it operates not with a blade but with a beam of light. By sending a focused laser beam through a patient's pupil, a surgeon can reach the interior of the eye without having to cut into the eye itself. The actual surgery causes little or no discomfort, there are no incisions to heal and no damage to other areas of the eye, and recovery time is minimal.
For all their high-tech wizardry, the application of lasers and other modern surgical techniques in ophthalmology would not have come about were it not for the researchers who first painstakingly figured out how the eye works and identified the causes of various defects in vision.
One long-held belief was that the lens, which lies just behind the pupil and helps to focus light on the retina, was the seat of vision and that removing it would result in blindness. The ancients had no notion of the retina and its crucial role.
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