Using fluorescein angiography, we studied the prevalence and characteristics of diabetic retinopathy in 40 patients with chronic pancreatitis complicated by diabetes and in 40 type 1 diabetics with comparable duration of diabetes. Retinopathy was found in 19 pancreatitis patients (47.5%) and in 20 type 1 diabetic patients (50%); it was background, minimal, or mild to moderate, without impairment of visual function, in all 19 pancreatitis patients and in 17 of the 20 type 1 diabetics. In the remaining three idiopathic diabetics, retinopathy was background of severe degree in two and proliferative, with impairment of vision, in one. No differences between patients with and without retinopathy were observed in fasting blood glucose, glycosylated hemoglobin, serum cholesterol, or triglyceride levels. The only significant difference (p less than 0.001) was the greater duration of diabetes in patients with retinopathy when compared with those without it (10.8 +/- 5.7 vs. 5.2 +/- 3.9 yr in pancreatitis patients; 11.2 +/- 5.0 vs. 5.1 +/- 3.5 yr in type 1 diabetics; mean +/- SD). Contrary to what is generally believed, the results indicate that the risk of retinopathy and the characteristics of this complication in patients with chronic pancreatitis and secondary diabetes are similar to those in patients with idiopathic diabetes.