Diabetes elevates glucose levels in the blood. These high blood sugar levels cause weakening of the blood vessels in the body, including the small blood vessels in the retina. (The retina is the part of eye that senses light and helps to send images to the brain.) This damage involving the retina blood vessels is called diabetic retinopathy.
Types of Diabetic Retinopathy
There are two types of diabetic retinopathy:
nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR).
NPDR is also commonly known as background retinopathy. It is an early stage of diabetic changes in the retina. In this stage, tiny blood vessels within the retina leak blood or fluid. This leakage causes swelling of the retina or the formation of deposits in the retina called exudates. The mild forms of NPDR usually do not affect vision.
PDR occurs when abnormal blood vessels begin growing on the surface of the retina or optic nerve. (The optic nerve sends the image information from the eye to the brain.) PDR usually occurs due to closure or failure of existing blood vessels which signals the retina to grow new ones in an attempt to restore blood flow in those areas. These new blood vessels, however, do not restore normal blood flow to the retina. Instead, the new vessels are fragile and increase the risk of bleeding as well as formation of scar tissue. Formation of scar tissue can than result in wrinkling or even detachment of the retina. The new blood vessel growth can also occur in other areas of the eye and can lead to neovascular glaucoma. The complications from PDR can be very serious and result in severe vision loss, including complete blindness.
How Should You Take Care of Your Eyes?
A medical eye examination is the only way to detect changes inside your eye. An ophthalmologist can often diagnose and treat serious retinopathy before you are even aware of any vision problems. Eye exams are especially important if you are pregnant and a diabetic. Pregnancy can cause you to start developing diabetic retinopathy or it can make existing changes worse.
Maintaining strict control of your blood sugar levels can significantly lower your risk of vision loss due to diabetic retinopathy.
When Should You Schedule an Eye Exam?
Diabetics should have an eye exam at least once a year. More frequent exams may be necessary depending on the type and severity of diabetic retinopathy present.
In addition, you should have your eyes checked promptly if you experience visual changes that affect only one eye, last more than a few days, or are not associated with a change in blood sugar. Rapid changes or fluctuations in blood sugar levels can cause blurred vision in both eyes.