Diabetic retinopathy

Retinopathy is the medical term for damage to the tiny blood vessels (capillaries) that nourish the retina, the tissue at the back of your eye that captures light and relays information to your brain. These blood vessels are often affected by the high blood sugar levels associated with diabetes.

When to seek medical advice

A common misconception among people with diabetes is, "If I can see well, there's nothing wrong with my eyes." That's false confidence. If you have diabetes, you're at risk of diabetic retinopathy, even if you don't have any vision problems. The early detection of diabetic retinopathy is your best protection against vision loss. For this reason regular eye examinations are essential.

The National Eye Institute recommends that if you have diabetes you should receive a comprehensive dilated eye exam at least once a year. In addition, if you have diabetes and become pregnant, you should have a comprehensive dilated eye exam as soon as possible. Additional exams may be recommended throughout your pregnancy.

See your eye doctor promptly if your vision becomes blurry, spotty or hazy. If diabetic retinopathy is found, the course of treatment depends on the severity of the condition and whether your vision is currently impaired or threatened by the retinal changes.

Screening and diagnosis

Your eye doctor will likely diagnose diabetic retinopathy, either nonproliferative or proliferative, if an eye examination reveals any of the following:

• Leaking blood vessels

• Retinal hemorrhage

• Swollen retina

• Fatty deposits (exudates) in the retina

• Areas of nerve fiber damage (cotton-wool spots)

• Changes in blood vessels, such as closures, beading or loops

• Microaneurysms

• Formation of new blood vessels (neovascularization)

• Vitreous hemorrhage

• Scar tissue formation with retinal detachment

As part of an eye examination, your doctor may include a diagnostic procedure called fluorescein angiography to identify leaking blood vessels.

In fluorescein angiography, your doctor injects a dye into a vein in your arm. As the dye circulates through your eyes, the blood vessels in your retina stand out as bright yellow when observed with a blue light. A camera takes flash pictures every few seconds for several minutes, providing your doctor with useful images.