Diabetes and Your Vision

Diabetes is a leading cause of blindness in the United States, and the best means of early detection of vision problems is to have an ophthalmologist examine your eyes by dilating them and observing the retina. It is recommended that all people with type 1 diabetes have annual eye exams starting five years after the onset of their condition. Those with type 2 diabetes should have an examination soon after their diagnosis is made. Any visual changes that occur should be taken seriously; such changes warrant a complete eye exam by an ophthalmologist.

Diabetes affects the eyes by damaging the retina, which is referred to as diabetic retinopathy. The retina is the part of the eye that is responsible for sensing light. Retinal damage can occur in two ways. First, the blood vessels that supply nutrients to the cells of the retina can become damaged as a consequence of high glucose levels in the blood that in turn cause bleeding and the formation of blood clots in them. The blood from these vessels that leaks into the eye can obscure light from reaching the retina, causing blindness. And if the retina cannot receive nutrients and oxygen because of a lack of blood flow in the vessels, the cells will die, causing permanent loss of vision.

Sometimes when small blood vessels in the retina are damaged in this way the body will produce new vessels in this area to try to deliver oxygen to the retinal cells. This can lead to far too many new blood vessels being formed in the retina, which in turn block out light and cause blindness. This condition is called proliferative diabetic retinopathy. The current treatment of this condition involves the use of a special laser to slow or stop new vessel overgrowth.

Blurring of vision can also occur when the blood glucose is high. These symptoms can sometimes be resolved when the blood glucose is brought under control. However, it is also known that high glucose levels can lead to nerve damage that can affect the way your eye moves. This is often a permanent condition. If the nerves to your eye muscles do not work properly, blurring of vision will occur.