The longer a person has diabetes, the higher the chance of developing diabetic retinopathy.
Prolonged periods of high blood sugar levels cause damage to the small blood vessels in the retina at the back of the eye. The retina is the light-sensitive film at the back of the eye that sends electrical impulses to your brain, allowing you to see. A healthy retina is essential for good vision.
With diabetic retinopathy, the blood vessels become leaky and then may close off.
The leaky vessels can lead to hemorrhages (spots of bleeding), clear fluid (serum) and exudates (blood fats and proteins) within the retina. This may also cause significant swelling, known as edema of the retina.
The blocked vessels can starve the retina of oxygen, leading to the growth of new, abnormal vessels as well as damage to the retina from lack of oxygen. Good control of diabetes, including blood glucose, blood pressure and blood cholesterol helps reduce the chances of developing retinopathy or having it progress to more serious stages.