Abstract
Purpose: :
To characterize diabetic retinopathy progression and risk markers for the development of severe macular edema prompting laser photocoagulation in cohort seven–year longitudinal study.
Methods: :
Fifty seven eyes in the mild nonproliferative retinopathy (NPDR) of 57 patients with type 2 diabetes mellitus were followed by performing eye examinations every 6 months on the first 2 years, and then at 2 years, and then at 2 years intervals, for the total period of follow–up of seven years . The eye examinations included fundus photography, fluorescein angiography, retinal leakage and retinal thickness measurements. Stable metabolic and blood pressure control was maintained during the initial two–year period with a mean HbA1c value of 8.2% ± 0.6 (mean ± SD), a mean systolic blood pressure of 140mmHg ± 12 (mean ± SD) and mean dyastolic blood pressure of 80mmHg ± 8.4 (mean ± SD).
Results: :
Thirty five eyes (61,4% of the total) showed an increase in the number of red dots in field 2 of less than 3/year, low leakage levels and normal foveal avascular zones (FAZ), indicating a slow progression patter. No eye from this group received photocoagulation during the 7 year follow–up. Twelve eyes (21%) showed characterised by a rapidly increasing number of red dots (>3/year) and high leakage levels (B). Five of these 12 eyes (41,5%) developed macular edema needing photocoagulation. Finally, ten eyes (17,6%) were identified by rapidly increasing number of red dots (> 3/ year) and clear abnormalities in the FAZ, representing an ischemic pattern of progression (c). Five of these 10 eyes (50%) developed macular edema needing photocoagulation.
Conclusions: :
Eyes with NPDR in type 2 diabetes showing rapidly increasing number of red dots in the posterior pole and either high leakage levels or FAZ abnormalities indicating disease progression are at greatest risk of developing severe macular edema needing photocoagulation.
Keywords: diabetic retinopathy • macula/fovea • retina