Diabetes is a systemic disease of faulty metabolism of sugar in the blood leading to damage to the small blood vessels throughout the body. Over 25 million people in the United States have diabetes. Seven million of those are undiagnosed.
Diabetes causes damage to the retina, the thin layer of light-sensitive tissue that lines the back of the eye. Light rays are focused onto the retina, where they are transmitted to the brain and interpreted as the images you see.
Diabetes causes damage to the small blood vessels within the retina causing these vessels to swell and leak fluid and blood or even close off completely. In some cases, abnormal new blood vessels grow on the surface of the retina. Diabetic retinopathy usually affects both eyes. People who have diabetic retinopathy often don’t notice changes in their vision in the disease’s early stages. But as it progresses, diabetic retinopathy usually causes vision loss that, in many cases, cannot be reversed.
Vision loss from diabetes occurs in several ways. When the blood vessels swell and leak fluid causing swelling in the retinal tissue, vision becomes distorted or blurred. If the swelling is not located in the center of the retina, the macula, vision may not be affected. Treatment at this stage involves preservation of vision. The macula is the portion of the retina that is responsible for our pinpoint vision, allowing us to read, see road signs, recognize a face, or anything requiring distinct vision. If the swelling is in the macula, vision will be significantly reduced. These damaged, small blood vessels may also close off preventing blood and nutrients from reaching that portion of the retina. That retinal tissue then dies and vision is not perceived in that area. If enough blood vessels close off, the eye responds by producing new blood vessels; however, these blood vessels are abnormal and lead to other problems. These new blood vessels leak and cause bleeding within the eye significantly affecting the vision. They can also cause scarring in the eye that leads to traction on the retina and eventually causes the retina to detach.
The best treatment for diabetic eye disease is prevention. To prevent problems from diabetes, it is essential to maintain tight blood glucose control. Equally important is to maintain normal blood pressure. Doing so may not cure diabetic retinopathy or restore normal vision, but it will slow the progression of the disease. Laser surgery uses a very bright, finely focused light to treat abnormal, leaking blood vessels, reducing the amount of fluid in the retina, allowing the swelling to resolve and vision to stabilize and possibly improve.
Laser treatments can also cause any new blood vessels to regress. This procedure can be done in the office with minimal discomfort. Some patients may need surgical intervention involving removing the vitreous, the clear gel that fills the eye, as well as any membranes, scar tissue, and blood caused by abnormal blood vessel growth and bleeding. Depending on the damage to the retina, sometimes laser treatment, gas injections, and oil are used at the time of surgery. These procedures are usually done in an outpatient surgery center. Medications can also be injected into the eye to treat the swelling and the new blood vessel growth. Medication injections can be given once or as a series of injections at regular intervals, usually around every four to six weeks or as determined by your doctor until the disease process is under control.
You should see your eye care specialist at least once a year if you have been diagnosed with diabetes. For those with Type I (juvenile onset) diabetes, your first diabetic eye exam should be around puberty or about 5 years after your diagnosis, which ever is sooner. For those with Type II (adult onset) diabetes, your first eye exam should be soon after your initial diagnosis as about 50 percent of these patients have some diabetic retinopathy at the time of their diagnosis. Your diabetic doctor can use the report of your eye exam to help monitor your diabetes. The blood vessels that diabetes damages are in every part of your body. The eye is the only place where we can examine these vessels and determine their health. By evaluating these vessels through a dilated eye exam, we can assess the health of the blood vessels throughout the entire body.