Preventing diabetic eye disease, or retinopathy, is an important goal of the NIH Research Clinic at Sacaton. Long-term diabetes can cause blood vessels in the retina of the eye to break down, leading to loss of vision and even blindness. Doctors don't know the cause.

There are two things people with diabetes can do to slow, and perhaps prevent that complication, according to Dr. William Knowler: with the help of their doctors, he advises, they should try to keep their blood sugar and blood pressure as close to normal as possible. Secondly, they should have regular eye exams with eye drops to detect any early signs of eye disease, such as small problems in the blood vessels of the retina.

These early signs, called "background retinopathy," usually do not affect eyesight by themselves, but they can lead to a more dangerous stage, called proliferative retinopathy. In this second stage, new blood vessels build up in the retina and branch out into the vitreous humor in the middle of the eye. These blood vessels break and bleed easily, causing a blood clot that steals sight.

The detailed eye exams that can help prevent blindness are available to all residents of the Gila River Indian Community at the NIH Clinic in Sacaton every two years. A patient with background retinopathy should have eye exams more often. The sooner retinopathy is found, the better, says Dr. Knowler.

If retinopathy advances and the changes are spotted soon enough, eye doctors do have treatments to prevent blindness in some cases. They can use lasers to seal damaged blood vessels, preventing them from forming the blood clots that can cause blindness. However, these treatments must be given at just the right time, before serious damage is done to the eye. Until researchers discover the causes of diabetic disease, Dr. Knowler says, "keeping appointments for eye exams can make the difference between keeping or losing eyesight."