Macular recovery time recorded by nyctometry--a screening method for selection of patients who are at risk of developing proliferative diabetic retinopathy. Results of a 5-year follow-up.

A 5-year study on the predictive value of the macular recovery time, as recorded by nyctometry, in the development of proliferative diabetic retinopathy in insulin-dependent diabetes mellitus has been completed. Seventy-seven patients with a median age of 30,8 years and a median duration of the disease of 15,8 years participated. In the follow-up period, 16 out of 20 patients initially showing abnormally prolonged macular recovery time had developed proliferative diabetic retinopathy the median duration from the initial investigation to the diagnosis of retinal neovascularization being 34 months. Contrary to this finding, only 4 out of 57 patients initially showing normal macular recovery had advanced into proliferative retinopathy, and the median duration until diagnosis of this condition was 45 months. It is concluded that nyctometry can serve as an easily performed screening method in selecting those at risk of developing proliferative retinopathy within a few years.