More than one million Australians are living with diabetes, and eye disease is one of the most common resulting complications. It’s even possible that some people unknowingly have severe diabetic eye disease before ‘suddenly’ going blind. In fact, diabetes is the leading cause of blindness in working-age adults.
Fortunately, most cases of blindness related to diabetes can be prevented with proper blood sugar, blood pressure and cholesterol management and avoidance of smoking.
Types of diabetic eye disease
The earlier these conditions are diagnosed and treatment initiated, the better.
This affects around 15% of people with diabetes. Persistently high blood sugar levels can damage the small blood vessels (capillaries) that deliver oxygen and nutrients to the light-sensing retina at the back of the eye.
There are three main types of diabetic retinopathy, which can vary in its degree of severity:
Non-proliferative diabetic retinopathy
This is can range from mild to severe. Capillary damage results in leakage of blood or fluid, causing the retina to swell. Although this stage of diabetic retinopathy usually causes minimal or no changes on vision, if the changes are severe, left untreated they can progress to proliferative diabetic retinopathy.
Proliferative diabetic retinopathy
This is the advanced stage of the disease, with growth of new but fragile blood vessels that bleed and can form scar tissue. Symptoms include blurred vision (which can occur suddenly). If these new vessels bleed or a retinal detachment occurs, the person can lose all vision.
Diabetic macular oedema
This occurs if swelling extends to the macula, which is the part of the retina responsible for central vision. Vision can become blurred and colours appear faded, resulting in trouble reading, recognising faces and driving. With good control of blood sugars, blood pressure, cholesterol and by not smoking, diabetic retinopathy can be reversible if it is in the mild to moderate stages. In more advanced cases, with new treatments for diabetic retinopathy, vision can often be at least partially recovered. Treatment options include intravitreal injections (injections into the eye), laser treatment and surgery.