Diabetes-Related Eye Conditions

People with diabetes are at 25 times greater risk for blindness.²⁰ People with diabetes who smoke, have poor nutrition, and do not control their diabetes have an even greater risk of developing eye complications. Because many people with diabetes have slower healing time, eye injuries - even minor corneal scratches - should not be taken lightly.

Retinopathy

Retinopathy is a common eye complication in people with diabetes. Poor glycemic control and longer duration of diabetes lead to increased rates of retinopathy in people with type 1 and type 2 diabetes. Retinopathy is the term used that describes the damage to the blood vessels in the back of the eye. The condition affects the retina's macula (the area responsible for fine visual acuity), causing vision reduction and potentially leading to blindness. It can also lead to the development of abnormal new blood vessels, which are fragile and can bleed into the center of the eye. This can lead to sudden loss of vision. Diabetic retinopathy, however, is treatable, and one of the most preventable causes of vision loss and blindness.

Early detection and treatment can prevent or delay blindness due to diabetic retinopathy in 90 percent of people with diabetes. Good glycemic control has been shown to reduce or delay by 76 percent the development of retinopathy in people with diabetes.²¹ Intensive therapy reduces the first appearance of any retinopathy by 27 percent. Retinal laser photocoagulation surgery can reduce the risk of severe vision loss from proliferative diabetic retinopathy (PDR) to 4 percent or less.²²

Optometrists and ophthalmologists can provide low-vision aids - from simple hand magnifiers to innovative optical devices - to help persons who have experienced un-correctable severe vision loss due to diabetic retinopathy. These eye care providers also can provide the care and services that allow people with diabetes to maintain good vision, which they need to maintain their quality of life and help control their diabetes (e.g., to read instructions, take medication, and drive to medical appointments).

Other Eye Complications

Other eye complications include diplopia (double vision) and frequent visual fluctuations. These complications tend to be more prevalent in people with type 2 diabetes.

Double vision. People with diabetes may complain about sudden onset of double images. Because this can be due to damage to the nerves leading from the brain directly to the eye it is important to see a doctor immediately. This may be due to mononeuropathy - damage to a single nerve - usually cranial nerves III, IV, and VI. The sixth and third nerves are most frequently affected. Third-nerve palsies occur with pupillary sparing in 80 percent of cases. Most diabetic third-nerve palsies usually resolve spontaneously within 2 to 3 months.

Vision fluctuation. Poor control of blood glucose levels may lead to a fluctuation in vision. These temporary visual fluctuations can occur because of fluid imbalance in the crystalline lens. When the glucose level is elevated, the lens thickens, causing the eye to become nearsighted. When the glucose level returns to normal, the lens can shrink back to its normal state. For those persons who need glasses, this constant state of flux can make it difficult to determine the best lenses for the glasses if the glucose level is poorly controlled.