Diabetes mellitus (DM) is a set of metabolic diseases in which the body cannot regulate the amount of sugar (glucose) in the blood. Whether you have type 1 or type 2 diabetes, uncontrolled sugar levels can cause serious visual impairment and blindness.
Many times, diabetes is seen in the eyes often times before the patient is even aware they have the disease. The retinal blood vasculature is abundant, so we can easily see the blood vessels and get a glimpse of what may be happening within the body. If diabetes is seen in the eye, it is known as diabetic retinopathy and treatment is required.
Treatment is done either with a laser or via drug injections (Avastin or Lucentis). The misconception is that treatment always improves vision; treatment simply slows or stops the progression of the bleeding. It will not reverse any damage that has already taken place, and it will only improve vision in some cases. Hence, the best way to preserve your eyesight if you are a diabetic is to control your blood sugar levels and be examined regularly by your eye care practitioner.