Diabetic retinopathy: Diabetes is a problem where the body loses the ability to control the amount of glucose, or sugar, in the blood. It is a disease that has become increasingly prevalent throughout the world and is now approaching a worldwide health crisis. Glucose is the fuel that your brain and nervous system use to keep running, but when the sugar levels are too high, it damages the small blood vessels and capillaries in all the body’s tissues. In the eye, the tissue most susceptible to damage is the retina. The retina acts like the film in the back of the eye that is responsible for picking up the visual image and sending it back to the brain.
The retina is very delicate and has more blood vessels in it per unit weight than any other tissue in the body. Therefore it is very sensitive to damage from high glucose levels, and damage to the retina, or diabetic retinopathy, eventually leads to damage to vision. A significant amount of damage may occur to the retina before the vision is affected, but once it occurs, the damage is permanent. This is why it is essential to prevent the problem through strict control of blood sugar with diet exercise medication and, if necessary, insulin. Periodic dilated eye exams are also essential to enable the ophthalmologist to diagnose retinopathy at an early stage when it can be effectively treated. Waiting until the vision is affected makes treatment more difficult and less effective.
Treatment for diabetic retinopathy often involves the use of a laser in the doctor’s office. These treatments generally last less than fifteen minutes and involve little, if any discomfort. Patients will note brilliant flashes of light, and a special contact lens may be used during the procedure to focus the laser and keep the eye open. The laser treatment may be directed at the macula, the central portion of the retina, in order to treat areas of swelling, or edema, which can lead to blurred vision if allowed to progress. When retinal damage reaches a severe level, new abnormal blood vessels will start to grow within the eye causing hemorrhaging and eventually scar tissue formation, retinal detachment and permanent total loss of vision. If new blood vessels or hemorrhage is diagnosed, the laser may be used to treat the peripheral portion of the retina in a procedure called Panretinal Photocoagulation. This treatment is a little more intense and is often broken up into two or more sessions. It rarely requires anesthesia, but occasionally an injected anesthetic may be used.
The goal of this treatment is to cause abnormal vessels to shrink up and stop bleeding. Any blood that is already present, which the patient may note as floating spots in the vision, will need to slowly absorb on its own or, if severe, be removed surgically in an operating room. Sometimes, certain medications may be injected directly into the eye in a procedure called intravitreal injection. This is a quick procedure that is performed in the office and has few side effects.
Many patients initially find the idea of these injections quite disturbing, which is a natural reaction. The reality, however, is that the procedure is usually very well tolerated and most patients who undergo it are surprised and relieved at how relatively painless and easy it is. These medications are often effective in shrinking up new blood vessel growth and improving macular swelling, but they may need to be repeated periodically. If the retinopathy becomes very advanced, either because it is diagnosed at a late stage, or because it does not respond well to treatment in the office, surgery in an operating room is sometimes necessary. This will usually involve removing the gel from within the eye in a procedure called vitrectomy, and removing any blood and scar tissue membranes that may be growing. This can be very effective in restoring vision, but at times, when the problems are too advanced, even surgery fails to restore vision and the eye will become blind.
Diabetic retinopathy is an example of a disease for which prevention, early diagnosis, and timely treatment make all the difference. Patients who maintain strict control over their blood sugar, who keep regular appointments with their ophthalmologist, and who undergo appropriate treatment early, ideally while they still have perfect vision, are much more likely to keep good vision throughout their lives.