What is diabetic retinopathy?

One of the possible complications of diabetes is called diabetic retinopathy and involves damage to the retina at the back of the eye. Depending on the extent of damage, vision may be slightly or moderately impaired or can lead to blindness. Prevention includes keeping blood glucose, blood pressure and cholesterol at healthy levels, not smoking, and having regular diabetes eye checks so any changes can be detected. Early treatment can help slow or stabilise eye damage.

What happens in diabetic retinopathy?

Diabetic retinopathy is an abnormality of blood vessels which supply the retina, the layer lining the inside of the eye, which acts like a film in a camera. These blood vessels leak fluid which causes a loss of reading vision or abnormal blood vessels develop which can haemorrhage and lead to a more severe loss of vision.

Who is at risk?

All people with diabetes are at risk of the condition, which is largely related to the duration of the diabetes. In younger insulin-dependent people with diabetes, the onset of the condition is rapid, whereas, in older people with diabetes, it comes on more slowly and the exact onset is therefore more difficult to pinpoint. After 10 years of the disease all people with diabetes will have some degree of retinopathy and about 40% to 50% will develop complications which can cause an effect on vision.

Can it be prevented?

Good control of the blood sugars will reduce the incidence of retinopathy and control of hypertension (high blood pressure) is also important. Smoking is associated with greater risk of the condition. The most important preventive measure with regard to visual loss from diabetes is regular examinations by an eye specialist to detect the early changes of retinopathy. Special care needs to be taken in pregnant diabetic patients.

Laser treatment

Laser treatment before symptoms is very effective in preventing loss of vision and is imperative, although maybe less effective, once symptoms have developed. Therefore, regular checks by an eye specialist to detect the changes before symptoms is absolutely mandatory, and particularly so after 10 years of diabetes.

The laser treatment may need to be quite extensive and consists of multiple small burns on the surface of the retina. This is performed as an outpatient sitting in front of a laser machine. Following the laser treatment the vision is quite blurred for about a week and after that vision largely recovers. The eye, however, remains less able to adapt to changes of light, particularly when going from light to dark conditions.

Other treatment

If the retinopathy progresses to haemorrhages and more damage to the retina, vitreoretinal surgery may be required.

Related topics

See also: Diabetes and eye problems and Quitting smoking and High blood cholesterol

Original material provided by Auckland Eye, 2005. Reviewed by everybody, September 2011.