Treating Diabetic Retinopathy - Diabetic Retinopathy: The Aging Eye Preventing And Treating Eye Disease

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Treating diabetic retinopathy

So far, there is no cure for diabetic retinopathy. But you can take steps to prevent vision loss — or at least to slow its progression.

Laser photocoagulation is the most effective treatment for diabetic retinopathy. When the problem is detected before the retina is severely damaged, this type of laser treatment can seal or destroy leaking blood vessels in the retina. There are two versions of the procedure. Both are typically performed in a doctor's office or eye clinic under local anesthesia.

Focal photocoagulation enables an ophthalmologist to identify individual blood vessels and seal them off with the laser. This method is often used to treat macular edema. The doctor uses a laser to make 20–50 tiny burns to seal the leaking blood vessels, which slows the leakage and reduces the amount of fluid in the retina. Local anesthetics prevent any discomfort during the procedure, and the surgery is usually completed in a single session.

If macular edema affects both eyes, only one is operated on at a time. A second session — usually a week or so later — will be needed to operate on the second eye. The procedure can cut the risk of further vision loss in half, and in a small number of people, it actually restores vision.

The second version of laser photocoagulation, called panretinal photocoagulation (PRP), is used in cases where the problem has advanced to proliferative retinopathy. The doctor makes 1,000–2,000 laser burns in peripheral areas of the retina, away from the macula (located at the center). Because so many laser burns are needed, treatment typically requires at least a couple of sessions. PRP decreases the stimulus for new blood vessel growth, causing the vessels to stop proliferating or regress and lowering the risk of hemorrhage or detachment. Peripheral vision, color vision, and night vision may become slightly impaired.

In situations where bleeding has become severe, the doctor may need to perform a vitrectomy before performing laser surgery (see "Vitrectomy").

In spite of all of the excitement about laser photocoagulation for diabetic retinopathy, the procedure isn't completely perfect. It won't prevent visual loss in everyone who suffers from diabetic retinopathy. However, studies have found it has a substantial success rate. One study from the American Diabetes Association involved 1,758 people who suffered from diabetic retinopathy. By the end of two years, severe visual loss had occurred in 16% of untreated eyes and only 6% of treated eyes. High-risk patients experienced the greatest benefit: Severe visual loss occurred in only 11% of the eyes treated with laser surgery, but in 26% of the untreated eyes.

Although the treatments available for diabetic retinopathy may not be perfect — that is, some people who are treated will still go blind — the chance that someone can benefit is great enough that surgery is typically recommended.

Last updated:	June 19, 2007