Diabetes is a disease that affects the body’s ability to produce or use insulin effectively to control blood sugar (glucose) levels. Although glucose is an important source of energy for the body’s cells, too much glucose in the blood for a long time can cause damage in many parts of the body, including the heart, kidneys, blood vessels and the small blood vessels in the eyes.
When the blood vessels in the eye’s retina (the light sensitive tissue lining the back of the eye) swell, leak or close off completely — or if abnormal new blood vessels grow on the surface of the retina — it is called Diabetic Retinopathy.
You may not know your eyes are harmed until the problem is very bad. Your doctor can catch problems early if you get regular eye exams. This is very important. The early stages of diabetic retinopathy don't cause changes in vision and you won't have symptoms. Only an eye exam can detect the problem, so that steps can be taken to prevent the retinopathy from getting worse.
Even if the doctor who takes care of your diabetes checks your eyes, you need an eye exam every 1 to 2 years by an eye doctor who takes care of people with diabetes. An eye doctor has equipment that can check the back of your eye much better than your regular doctor can. If you have eye problems because of diabetes, you will probably see your eye doctor more often. You may need special treatment to prevent your eye problems from getting worse.
The doctor will check your vision using a chart of random letters of different sizes. This is called the Snellen chart. You will then be given eye drops to widen (dilate) the pupils of your eyes so that the doctor can better see the back of the eye. You may feel stinging when the drops are first placed. You may have a metallic taste in your mouth. To see the back of your eye, the doctor looks through a special magnifying glass using a bright light.
However, even without Retinopathy, Something to remember: diabetes can cause vision in your eyes to change. If your blood sugar levels change quickly, it can affect the shape of your eye’s lens, causing blurry vision, which goes back to normal after your blood sugar stabilizes.