Diabetic retinopathy

Overview

Diabetic retinopathy is one of the most severe complication of diabetes mellitus. This condition is considered a major cause of blindness, particularly among working-age adults.

First time diabetic retinopathy may cause no symptoms. However, without timely medical assistance it can cause blindness.

Symptoms

The following symptoms can point to diabetic retinopathy:

• Blurred vision
• Floaters (black spots) or flashing lights in the field of vision
• Sudden and painless vision loss

Diabetic retinopathy usually affects both eyes.

When to see a doctor

Careful management of diabetes is the best way to prevent vision problems. If you have diabetes, see your doctor for a yearly ophthalmic examination which will help to identify complications in a timely manner.

Contact your doctor immediately if you have any noticeable symptoms.

Classification and pathogenesis

There are two types of diabetic retinopathy: early diabetic retinopathy or nonproliferative diabetic retinopathy and advanced diabetic retinopathy known as proliferative diabetic retinopathy.

Nonproliferative retinopathy develops first and causes increased capillary permeability, microaneurysms, hemorrhages, exudates and macular edema.

Proliferative retinopathy develops after nonproliferative retinopathy and is more severe; it may lead to vitreous hemorrhage and traction retinal detachment. Proliferative retinopathy is characterized by abnormal new vessel formation (neovascularization), which occurs on the inner surface of the retina and may extend into the vitreous cavity and cause vitreous hemorrhage.

Clinically significant macular edema can occur with nonproliferative or proliferative retinopathy and is the most common cause of vision loss due to diabetic retinopathy.

Risk factors

Anyone who has diabetes can be exposed to diabetic retinopathy. Risk of developing diabetic retinopathy can increase as a result of poor control of blood sugar level, high blood pressure, high cholesterol and smoking.

Diagnosis

Diagnosis of diabetic retinopathy includes several stages:

• Funduscopy
• Color fundus photography
• Fluorescein angiography
• Optical coherence tomography

Diagnosis is by funduscopy. Color fundus photography helps grade the level of retinopathy. Fluorescein angiography is used to determine the extent of retinopathy, to develop a treatment plan, and to monitor the results of treatment. Optical coherence tomography is also useful to assess severity of macular edema and treatment response.

Treatment

Treatment depends largely on the type of diabetic retinopathy and how severe it is. If you have nonproliferative diabetic retinopathy, you may not need treatment right away. It will suffice to see your ophthalmologist constantly and keep blood sugar level under control to slow the disease progression.

• Proliferative diabetic retinopathy requires surgical treatment. Depending on the specific problems with your retina, options may include:
• This laser surgery can stop or slow the leakage of blood and fluid in the eye. During the procedure, leaks from abnormal blood vessels are treated with laser burns.
• Photocoagulation is usually done in your doctor’s office or eye clinic in a single session. If you had blurred vision from macular edema before surgery, the treatment might not return your vision to normal, but it’s likely to reduce the chance the macular edema may worsen.
• Panretinal photocoagulation. This laser surgery can shrink the abnormal blood vessels. During the procedure, the areas of the retina away from the macula are treated with scattered laser burns. The burns cause the abnormal new blood vessels to shrink and scar. It’s usually done in several sessions.
• This procedure uses a tiny incision in your eye to remove blood from the middle of the vitreous body as well as scar tissue that’s tugging on the retina.
• Anti-VEGF intravitreal injection treatment. Your doctor may suggest injecting medication into the vitreous body. These medications, called vascular endothelial growth factor (VEGF) inhibitors, may help stop growth of new blood vessels by blocking the effects of growth signals the body sends to generate new blood vessels.

Surgery often slows or stops the progression of diabetic retinopathy, but it’s not a cure. Because diabetes is a lifelong condition, future retinal damage and vision loss are still possible.

Prevention

You cannot always prevent diabetic retinopathy. However, regular ophthalmic examination and careful control of blood sugar level and blood pressure can help prevent severe vision problems.

If you have diabetes, you could reduce your risk of getting diabetic retinopathy by implementing the following recommendations:

• Manage your diabetes. Make healthy eating and physical activity part of your daily routine. Try to get at least three hours of moderate aerobic activity, such as walking, each week.
• Monitor your blood sugar level. You may need to check and record your blood sugar level several times a day.
• Keep your blood pressure and cholesterol under control.
• Quit smoking. Smoking increases your risk of various diabetes complications, including diabetic retinopathy.
• Pay attention to vision changes. See a doctor right away if you experience sudden vision changes.