EYES, KIDNEYS and the FEET are the three most effected organs by diabetes.

Diabetic retinal disease is the most common cause of blindness in adults in the US. The changes in the retina are time sensitive, the longer the duration of diabetes the higher is the risk of having the diabetic retinal disease.

Both types of diabetes will cause vision problems if present for a long enough time (over 10 years). For instance, 90% of insulin-dependant diabetic patients will have diabetic changes in their eyes. Studies have shown that if the level of blood sugar, blood pressure, blood cholesterol and blood triglyceride are kept at normal levels, the risk of developing retinal disease will be much reduced.

Incidence of diabetes is on the rise and so it is for diabetic retinal disease as well. Frequent eye exams for diabetic patients is very essential in detecting early signs of retinal changes. Diabetes is generally a disease of very small blood vessels (microvasculature causing small aneurysms, abnormal fragile vessels and blockage of the very small vessels). These vascular damages lead to edema, bleeding and ischemia (low oxygen and nutrients in the tissue) in the retina and macula which eventually will blur vision.

The wall of the effected fine vessels turn into small pouches (aneurysm), which can leak blood into the retina or over the retina, become occluded to cut off blood supply to surrounding retina (ischemia, soft exudates). Leakage of blood causes edema and blood products accumulate inside the retina and can be seen as yellow hard exudates. An important feature of the changes is the development and proliferation of new fragile blood vessels due to a substance with angiogenesis properties. The existence of this substance has been the basis for research to develop medications that neutralizes it. Presence of these new vessels is indicative of the severity of the diabetic retinal effects. The bleeding over the retina will gradually start fibrous bands that pull on the retina and cause retinal detachment with severe effect on the vision.

Edema of the macula is also serious and will thicken the macular tissue and reduce visual acuity. The ischemic phenomenon progresses and becomes the stimulus for the development of new fragile vessels and further deterioration of the retinal diabetic condition. The ischemia, or in a sense the dead retina, is postulated to be the cause of new vessel growth, and it is theorized that the elimination of that dead tissue (ischemic retina) by laser will improve the condition and will allow the existing oxygen and blood supply to nurish the remaining normal parts of the retina.

In the early stage of diabetes, the retina looks normal under clinical methods of examination. But gradually signs of retinopathy appear as different types of bleeding (inside and/or over the retina, into vitreous), hard and soft exudates, macular edema and so on will be seen on dilated retina examination. Injecting a yellow dye (fluorscein dye ) into the vein of the patient’s arm and taking serial pictures of the retina which shows the blood vessels, any leakage and ischemic parts of the retina, are very helpful in the evaluation of the status and degree of the effects of diabetes on the retina.