DR MAXWELL ADEYEMI

The diagnosis of diabetes comes with the possibilities of certain complications, one of them an eye disease known as diabetic retinopathy. As the name suggests, retinopathy affects the retina, a thin layer of light-sensitive tissue that lines the back of the eye. It can lead to blindness.

With diabetic retinopathy the blood vessels in the retina become damaged and begin to swell and leak. The vessels may also close down so that blood doesn't pass through. Sometimes, abnormal new blood vessels begin to grow on the retina. All of these changes can affect your vision adversely.

Diabetic retinopathy can occur in both type 1 and type 2 diabetes, as well as gestational diabetes (diabetes occurring during pregnancy). It is the most common cause of irreversible blindness. It occurs in more than half of the people who develop diabetes.

For those with type 1 diabetes, the average age of onset for diabetic retinopathy is five to 14 years, while for those with type 2 diabetes it is ages 40 to 60.

Along with retinopathy, a condition called macular edema can occur. This involves a swelling of the macula, an area near the central part of the retina that has the keenest vision. About half of people with diabetic retinopathy develop macular edema.

Causes

The primary cause of diabetic retinopathy is sustained high blood sugar, which over time can harm the blood vessels in the retina. Diabetes damages the tiny blood vessels that nourish the retina. The condition can sneak up on patients but regular eye exams can detect early changes that might be worrisome. The key, is identifying retinal changes before a patient has vision loss. Glucose control and regular follow-up with a retina specialist is essential.

Risk factors

Besides high blood sugar, several factors increase the risk that a person with diabetes will develop diabetic retinopathy. These include:

• High cholesterol levels

• High blood pressure

• Smoking

• Being of African, Hispanics, or Indian descent.

People in these groups who have diabetes have a higher likelihood of developing retinopathy than people of other races with diabetes.

Signs and symptoms

It's very possible to have diabetic retinopathy without knowing it. In early stages there are often no symptoms. As the condition progresses, however, you will likely notice a variety of symptoms, such as:

• An increasing number of ''floaters," those specks that float across your line of vision

• Blurry vision

• Seeing flashes

• Having distorted vision

• Seeing a blank or dark area in your visual field (blind spots)

• Seeing dark spots across your field of vision

• Having poor vision at night

• Noticing that colours appear faded or washed out

• Difficulty reading or doing detail work

• Losing vision

Diagnosis

Regular eye exams are crucial to detect diabetic retinopathy and, if it is diagnosed, to monitor the condition. If you are diagnosed with type 2 diabetes, you should get an initial eye exam as soon as possible and then annua