Floaters – Simple Test Predicts Health Risk
14 Apr 2002
Some people are prone to see pink elephants now and then for good reason. But others who never misbehave on Saturday night may suddenly start to notice spots, threads or cob-web like structures floating in front of their eyes. A few people find them terribly annoying. Others fret that they may herald the onset of a serious eye problem. Or even end in blindness. What causes these floaters? And when do they indicate an eye emergency has happened?
Many people are too embarrassed to admit they see floaters. The admission is more likely to set the stage for a joke than a helpful reply. Yet most people can see floaters, if they look for them, against a clear sky or a white wall.
Floaters are much like gray hair or wrinkled skin. The eye ages like any other organ in the body. But each part of the eye gets its wrinkles in a different way. For instance, the need to back away from the telephone book is the result of the lens becoming more rigid with age.
On the other hand floaters occur because of changes in the vitreous which fills most of the space inside the eye. During youth the vitreous of the eye is crystal-clear and easily transmits light to the retina.
But as we age this clear gelatinous vitreous starts to degenerate and dots and threads of various sizes appear. These moveable objects then cast shadows on the retina and patients seen them in front of their eyes.
Some people become compulsive about floaters and are constantly searching for them. The more they look the more they find floaters that had been present for some time.
The majority of floaters are of no importance. One famous Harvard professor always gave this sage advice to patients, "make them your friend". But there are times when a red light should flash on when you see floaters.
A sudden appearance of spots and threads in the vision may mean a retinal attachment has occurred. Other patients may suddenly see flashes of light, sparks or a curtain falling over part of their vision.
Retinal detachment is a serious complication and if left untreated can lead to loss of vision. It’s often caused when fibrous bands form in the vitreous jel and become attached to the back part of the eye. Constant traction on the retina may cause a detachment. But whatever the cause patients need immediate care. The sooner a retinal detachment is treated the better the result.
Some people are more prone to retinal detachment. For instance, people who are near-sighted are more likely to develop this problem. Diabetics are also more susceptible to another type of detachment caused by scar tissue.
Retinal detachment is also a serious complication of cataract surgery. The problem occurs in up to two percent of those who have this operation. And in 50 percent of cases this complication follows within a year of surgery
Several procedures are available to treat retinal attachments. Retinal surgeons often use laser therapy and cryosurgery (intense cold) to seal the tear and reattach the retina.
Another procedure called, "pneumatic retinopexy" can be performed. This involves injecting a gas bubble into the eye and placing it over the tear. This blocks further release of fluid and allows fluid underneath the retina to be absorbed.
"Scleral buckling" is the time-honoured procedure. The detachment is first treated with cryosurgery. Then a soft silicone band is placed around the eyeball. This helps to bring the retina closer to the back part of the eye and promotes healing.
Some patients with major problems are treated by "vitrectomy". In this procedure the vitreous is removed to stop it from tugging on the retina.The vitreous is then replaced with air or gas. Over a period of time the air or gas is replaced by the body’s own fluid.
Vitrectomy is normally used as a last resort. In part because 80 percent of patients who have never had a cataract develop one within six months of this procedure.
Improvement in vision may take weeks or months depending on the severity of the detachment. But fortunately the retina can be reattached in 95 percent of cases.
