Patterns of Retinopathy Progression in a Five–Year Follow–Up of Mild Nonproliferative Retinopathy in Diabetes Type 2: Development of Clinically Significant Macular Edema

Abstract

Abstract: : Purpose: To characterize retinopathy progression and development of clinically significant macular edema (CSME) in the initial stages of retinal disease in diabetes type 2. Methods: Fifty seven eyes of 57 patients with type 2 diabetes mellitus and mild nonproliferative retinopathy were classified in three different retinopathy progression phenotypes (A, B and C) after an initial two year follow–up period, involving eye examinations every 6 months. Thereafter, they were examined at yearly intervals for another 3 years, completing a five–year follow–up period. All patients were examined by fundus photography, fluorescein angiography and had retinal leakage and retinal thickness measurements performed. Results: Of the 37 eyes (65% of the total) showing progression pattern A, in the initial two–year period of follow–up, only 1 developed CSME (3%) at the last examination of the five year follow–up. Of the 12 eyes (21%) showing pattern B, 4 eyes (30%) developed CSME, 2 at the three–year examination and the other 2 at the five–year examination. Of the 8 eyes (14%) identified with pattern C, 4 eyes (50%) developed CSME; 3, at the three–year examination and 1 at the four–year examination. Increases in leakage and thickness are prominent in pattern B whereas increases in capillary closure characterize pattern C. Conclusions: The development of CSME over a five–year period of follow–up in eyes with mild nonproliferative retinopathy and diabetes type 2 is rare in the more common progression pattern A. This is in contrast with progression patterns B and C where there is frequent development of CSME.

Keywords: clinical (human) or epidemiologic studies: natural history • diabetic retinopathy • imaging/image analysis: clinical