Symptoms of diabetic retinopathy

Many people with mild diabetic retinopathy have no synptoms. In more advanced cases however, blurred vision, floaters or sudden catastrophic loss of vision can occur in one or both eyes.

Who gets diabetic retinopathy?

The chances of a diabetic developing diabetic retinopathy depends on a number of things:

• The duration of diabetes. The longer diabetes has been present, the more likely it is that there will be some diabetic retinopathy. Once it is present it tends to worsen as time passes. It is unusual to see much diabetic retinopathy in people who have been diabetic for less than five years. It is possible however. Some patients have been diabetic for longer than they realise, so it is even possible for diabetic retinopathy to be present at the time of diagnosis of diabetes.
• Control of blood sugar levels. The poorer the control of blood sugar levels, the more likely it is that diabetic retinopathy will develop and the more likely it is that it will worsen.   
• Control of other vascular risk factors. Poor control of other vascular risk factors can worsen or accelerate the progress of diabetic retinopathy. This particularly applies to blood pressure control. Other risk factors such as poor exercise patterns, obesity, tobacco smoking and poor control of abnormal blood lipids (cholesterol and triglycerides) also contribute to worsening of the condition.

Can it be prevented or slowed?

Yes. Attention to the issues described above can prevent or at least slow the progress of the condition.

Unfortunately, even with scrupulous attention to these things, diabetic retinopathy can still occur and can still cause blindness.

It is therefore important for diabetics to have a regular eye examination by a skilled eyecare practitioner.

Diabetics should have an eye examination at or around the time their diabetes is diagnosed and at regular intervals thereafter as advised by their general doctor or as per the national guidelines applicable in the area where they live. This is the single most important measure in the prevention of diabetic blindness.

Can diabetic retinopathy be treated?

Yes. Apart from the preventative measures above, diabetic retinopathy can be treated quite effectively as long as it is diagnosed and treated early enough.

Laser treatment

The mainstay of treatment is laser. Laser treatment is usually applied through a special contact lens in an outpatient setting and the patient can go home after having it. The treatment is not usually painful. Areas of the retina are treated with tiny laser burns if there is significant leakage of fluid, especially at or near the macula, or if there are areas where the retina is affected severely by poor circulation causing ischaemia (lack of adequate oxygen supply).

The aim of treatment is to help prevent further leakage, to promote reabsorption of fluid from the retina and reduce the stimulus to new vessel growth. In cases of severe ischaemia or when new blood vessels are already present, the aim is to apply a sufficient number of retinal laser burns, often thousands, to cause the new vessels to regress and prevent any further vessels from developing.

Repeated treatments are usually needed. If diabetic retinopathy is too advanced before laser treatment is undertaken, it may fail to improve significantly and may continue to progress, even to the point of blindness in both eyes.

This fact underlines the importance of regular screening to detect diabetic retinopathy early and then start laser treatment as soon as it is needed.

Surgical treatment

Surgical treatment may be possible for very advanced cases of the condition where there has been severe bleeding in the eye, scar formation or retinal detachment. Surgery however is normally reserved as an attempt to rescue desperate cases of advanced diabetic retinopathy from blindness.

Other treatment

New forms of treatment include injecting drugs into the eye to reduce swelling in the retina and suppress new vessel growth. These are similar drugs to those used in the treatment of wet macular degeneration.

Can diabetes affect the eye in other ways?

Yes. Diabetes is a known risk factor for cataract and can contribute as a general vascular risk factor to other vascular diseases of the eye.

Note: This information is general in nature and is not a substitute for specialist medical advice. Have your eyes checked regularly every two years, even if you have not noticed any symptoms or changes.