Diabetes mellitus is a common condition that has a significant effect on the eye. In the early stages of diabetes, fluctuating blood sugar levels can cause changes in the refractive error of the eyes, and patients may complain that they need new glasses. Later, after patients have had diabetes for a number of years, changes that can affect vision begin to develop in the retina.

Laser treatment can be a very effective means to prevent diabetes from threatening a person's vision. It is important that patients with diabetes be seen yearly to assess the progression of retinal changes and promptly begin any required treatment.

The photographs below show an example of a normal retina and one that has changes characteristic of a patient with moderately advanced diabetes mellitus. Laser treatment, as shown in the last photograph, closes leaking blood vessels and helps prevent growth of abnormal blood vessels.