These pages are best viewed with Netscape version 3.0 or higher or Internet Explorer version 3.0 or higher. When viewed with other browsers, some characters or attributes may not be rendered correctly. The prevalence of retinopathy is strongly related to the duration of diabetes.
Diabetic retinopathy poses a serious threat to vision.
Screening strategies depend on the rates of appearance and progression of diabetic retinopathy and on risk factors that alter these rates. Vision-threatening retinopathy usually does not appear in type I patients in the first 5 years of diabetes, nor before puberty. Over the subsequent two decades, nearly all type I patients develop retinopathy. Vision loss with diabetic retinopathy results from several mechanisms. First, central vision may be impaired by macular edema or capillary nonperfusion.