PROGRESSION OF RETINOPATHY AND ALTERATION SF THE BLOOD-RETINAL BARRIER IN PATIENTS WITH TYPE-2 DIABETES - A 7-YEAR PROSPECTIVE FOLLOW-UP-STUDY

Background:The study was carried out to evaluate the correlation betwe en blood-retinal barrier (BRB) permeability and the progression of dia betic retinopathy (DR), defined by development of ''need for photocoag ulation'', over a 7-year period by means of vitreous fluorometry (VF). Methods: Forty type 2 diabetic patients with minimal or no retinopath y, aged 40-65 years (mean 53.9 + 7.3 years), were followed up prospect ively for 7 years. Investigations including standard ophthalmological examination, fundus photography, fluorescein angiography and VF were p erformed at entry and 1, 4, 5 and 7 years later. Only one eye per pati ent was included in the study. Need for photocoagulation was based on Early Treatment Diabetic Retinopathy Study protocols and decided by th e attending ophthalmologist Results: After 7 years of follow-up a tota l of 22 of the 40 eyes bad received photocoagulation. The eyes that ne eded photocoagulation were those that had higher VF values at the entr y of the study and showed higher rates of deterioration (initial value s 5.1 + 1.9 vs 2.8 + 1.5x10(-6) min(-1), P<0.001; annual increase in l eakage for the first year, 1.5 + 0.8 vs 0.5 + 1.0x10(-6) min(-1): P<0. 001,). The eyes that did not need photocoagulation during the 7 years of follow-up showed stable VF readings (-0.1 + 1.2x10(-6) min(-1), dif ference between initial values and 7 years later). Conclusions: Abnorm ally high VF values and their rapid increase over time are good indica tors of progression and worsening of the retinopathy in diabetes type 2.