Diabetic retinopathy is a complication of diabetes that affects the eyes. The length of time a patient has diabetes determines the likelihood of developing diabetic retinopathy. Over 40 percent of patients in the United States who are diagnosed with diabetes have some form of the disorder.
The most common diabetic eye complication, diabetic retinopathy is a leading cause of blindness in American adults. Diabetic retinopathy causes the blood vessels that supply nourishment to the retina, the light-sensitive lining in the back of the eye where vision is focused, to weaken, swell and leak, causing a loss of vision.
Symptoms of Diabetic Retinopathy
In the early stages of diabetic retinopathy, patients usually do not show symptoms. Treatment is not always required. Patients have to monitor their blood sugar level to prevent the disease from progressing. If the disease does progress, prompt treatment is necessary to preserve vision.
Patients who develop diabetic retinopathy may not notice any changes to their vision at first. In its earliest stages, this condition causes tiny areas of swelling in the small blood vessels of the retina. Once symptoms are present, they may include:
- Blurred or double vision
- Seeing flashing lights, blank spots, or dark floaters
- Pain or pressure in either or both eyes
- Problems with peripheral vision
In its advanced stages, diabetic retinopathy can cause blindness. This damage is irreversible.
During any stage of diabetic retinopathy, a condition known as macular edema can develop. Macular edema is the buildup of fluid in the macula, the light-sensitive part of the retina that allows us to see objects with great detail. As the macula swells, vision becomes blurred. About half of the people with proliferative retinopathy are diagnosed with macular edema.
Stages of Diabetic Retinopathy
Diabetic retinopathy is considered to have four stages, each one increasingly serious. These stages are:
- Mild nonproliferative retinopathy
- Moderate nonproliferative retinopathy
- Severe nonproliferative retinopathy
- Proliferative retinopathy
As the disorder worsens, more and more blood vessels are affected. By the time a patient has proliferative retinopathy, the body is creating new blood vessels to replace the ones that are blocked. The problem is that the newly created blood vessels have very thin walls. If they leak blood, the patient may suffer severe vision loss or blindness.
Diagnosis of Diabetic Retinopathy
Diagnosis of diabetic retinopathy requires a thorough eye examination and some of the following tests:
- Visual acuity test
- Dilated eye examination
- Tonometry test
- Retinal exam
- Fluorescein angiogram
Prior to some of these tests, eye drops containing a stain are administered so that the doctor can see delineated areas more clearly.
Treatment of Diabetic Retinopathy
Other than controlling blood pressure, blood cholesterol and the levels of blood sugar, treatment is not needed during the first three stages of diabetic retinopathy. The fourth stage, proliferative retinopathy, is treated with a laser surgery known as scatter laser treatment. During the procedure, the abnormal blood vessels are ablated causing them to shrink. This procedure works best once the blood vessels begin to bleed. Severe blood vessel bleeding may need to be surgically corrected with a vitrectomy procedure to remove the blood from the eye.
Treatment for macular edema usually includes a laser procedure called focal laser treatment. During this procedure, several hundred small laser burns are made in the areas of retinal leakage to reduce the amount of fluid in the retina. This helps reduce the risk of vision loss and may improve lost vision in a small number of cases. Focal laser treatment is performed in the doctor's office and can usually be completed in just one session.
Reducing the Risk of Diabetic Retinopathy
Patients with diabetes should have an annual comprehensive dilated eye exam. Over 40 percent of patients with diabetes in the United States have some form of diabetic retinopathy.
The risks of developing diabetic eye disease can be minimized by:
- Monitoring changes in vision
- Keeping blood glucose levels low
- Monitoring and managing blood pressure levels
- Eating a healthy diet
- Participating in a regular exercise routine
- Monitoring and managing cholesterol levels
Patients with proliferative retinopathy can reduce their risk of blindness by 95 percent by keeping up with their medical examinations and getting any necessary treatment promptly.