[Iris angiography studies in patients with diabetes mellitus]

Fluorescence angiography of the iris was performed on 75 patients with diabetes mellitus. The changes in the iris were classified as iridopathia diabetica simplex (ID-s) and iridopathia diabetica proliferans (ID-p), corresponding to similar changes in diabetic retinopathy. Thus punctate leakage of dye, especially around the pupillary margin, was classified as ID-s, whereas additional, angiographically verified new vessel formation was described as ID-p. 69 of the 75 patients (92%) showed diabetic changes of the iris. Of these, 50 (67%) had ID-s changes and 19 (25%) had ID-p changes. The incidence of diabetic iris changes appeared unrelated to age but appeared to increase with duration of the diabetes. A correlation between the onset of diabetic vascular changes of the iris and that of the retina could not be confirmed: the diabetic changes in the iris vessels can precede those of the retina whereas, on the other hand, almost all patients with a diabetic retinopathia also show an iridopathy. The clinical value of iris angiography lies therein that the first findings of diabetic vascular damage can be seen in the iris earlier than in the retina, the iris appearing normal on slit-lamp microscopy.