The Blister That Can Blind

The first thing Dr. Ronald G. Michels tells any patient with a detached retina is that he or she has suffered "one of the most serious things that can happen to the eye," and that if surgery isn't performed promptly, total blindness can result. Michels, 38, an associate professor of ophthalmology at Johns Hopkins University's Wilmer Eye Institute who performed the retinal reattachment operation on Sugar Ray Leonard, is one of the nation's most renowned eye surgeons and an expert on diseases of the retina. Approximately 20,000 Americans annually develop detached retinas, a condition usually associated with aging. Most of Michels' patients are well into middle age. Those as young as the 26-year-old Leonard have usually been victims of some sort of trauma.

In explaining a detached retina to a patient, Michels asks him to think of the eye as a rubber ball. The inside of the ball is filled with a clear jellylike substance called the vitreous. If the ball were sliced in half, the retina would be the thin, delicate layer of tissue that lines the entire inside of the back half of the ball. "The best way to understand the retina function," says Michels, "is to think of it as the film in a camera. It is the part of the eye on which the image is actually focused and from which that image is transmitted to the brain."

A retinal detachment usually begins when the vitreous gel for one reason or another pulls on the retina, breaking or tearing the retinal tissue. Fluid then seeps through the tear and accumulates as a kind of blister beneath the retina, causing more of the retina to become detached from the wall of the eye. The blister can begin as a tiny one, depending upon the size of the tear, but it almost always grows larger, with more retina becoming detached—like paint blistering off a wall.

There are two different sets of symptoms. When the initial tear occurs, the patient will see light flashes, and then "floaters"—spots, cobwebs, dots or squiggly lines. Once retinal detachment begins, part of the visual field is lost. Shadows, clouds, veils or dark areas begin to appear. In its least serious manifestation, the detachment occurs on the outer sides or bottom of the eye, and vision impairment appears in the peripheral field. But if the detachment spreads to the center of the back of the eye—the macula, which controls the sharpest part of the vision—the damage can be much more serious.

In any case, prompt surgery is the only means of correction. If the condition is caught as soon as the tear in the retina occurs, before detachment has begun, the tear can be sealed off relatively simply either with a freezing treatment, called cryotherapy, or with a laser beam. But if detachment has already begun—as in Leonard's case, in which 40% of the retina was reported to have been detached—a more complex operation, called scleral buckling, is required. In this technique, the surgeon makes an incision through the clear membrane that covers the sclera, the white part on the outside of the eye. Then he indents the sclera by attaching pieces of silicone rubber so that the wall of the eye comes in contact once again with the torn part of the retina.

After such an operation the success rate for complete anatomical reattachment of the retina is better than 90%, although some cases require more than one operation. However, Michels points out that this high rate shouldn't be misinterpreted. "We're talking about reattachment, not restoration of normal vision," he says. "How much vision can be restored depends on how long the retina had been detached and how extensive the detachment was. If the retina was detached for a long time—and long can be only a matter of days—there can be irreversible damage done to the retina, and total restoration of sight is impossible to achieve."

In fact, 100% restoration of normal vision after reattachment is not possible in most cases. When the retina is detached from the wall of the eye, it's deprived of approximately half of its blood supply, and its cells begin to deteriorate. Reattachment can stop, and partially reverse, the deterioration. A patient may have an inherited weakness in the eye that makes him predisposed to retinal detachment, or it may occur as a result of aging. The other most common cause is trauma, either from a severe blow causing an immediate and acute retinal tear or from continued blows that cause deterioration of the vitreous gel.

Michels declines to discuss the specifics of Leonard's case beyond saying that the symptoms were caught "early" and the detachment was "partial." Had Leonard defended his title against Roger Stafford last Friday in Buffalo, the damage to his left eye almost certainly would have become much, much worse. As for Leonard's future, Michels stresses that that determination can't be made for at least six months.

Michels advises all postoperative patients to avoid activities like skydiving and diving into swimming pools, as well as contact sports. "Jogging, swimming, tennis or golf would be rigorous activities a patient could resume without danger," he says. "You certainly want to avoid a situation where you might get a major blow to the eye."

What, then, of the professional athlete? "I think each case has to be individualized," Michels says. Though no scientific data exist, Michels acknowledges that athletes in contact sports are at a much higher risk than the general populace. Dave Bing suffered a detached retina in 1972 while playing for the Detroit Pistons and after surgery resumed his All-Star level of play. But of all athletes, boxers, who receive countless blows to the eyes a week while training for a fight—not to mention the fight itself—are the most susceptible to retinal damage. Since 1979 three U.S. boxers besides Leonard have suffered serious retinal injuries. Two resumed their careers; one didn't.