MACULAR THICKNESS CHANGES FOLLOWING PANRETINAL PHOTOCOAGULATION IN PATIENTS WITH SEVERE DIABETIC RETINOPATHY

BACKGROUND Diabetes is a metabolic disorder due to dysfunctional metabolism of glucose that arises out of the ineffective production or action of the glucose-regulating enzyme called insulin. Type I diabetes results due to ineffective production and type II results due to the in effective action of insulin. Diabetic retinopathy (DR) is a highly specific vascular complication of both type 1 and type 2 diabetes mellitus. Diabetic retinopathy predominantly is a microangiopathy in which small blood vessels are particularly vulnerable to damage from hyperglycaemia. The aim of this study was to evaluate macular thickness changes occurring following PRP among severe Diabetic Retinopathy patients. MATERIAL AND METHODS This prospective observational study was conducted in Sarojini Devi Eye Hospital over a period of 24 months from November 2015 to October 2017. Patients with severe diabetic retinopathy - severe and very severe NPDR or PDR with or without macular oedema, who required PRP, were included in the study. OCT was done in all the patients included in the study before PRP. After completion of PRP, patients were followed up at 1 week, 1 month and 3 months and OCT was done at every visit. RESULTS Mean macular thickness at 1st week, 1st month and 3rd month were compared to mean macular thickness before PRP and their variation were analysed. Patients with Macular Oedema-There is sudden increase in macular thickness at 1st week following PRP and thereafter gradually decreased. Patients without Macular Oedema-There is sudden increase in macular thickness at 1st week following PRP and thereafter gradually decreased. Mean macular thickness at 3rd month were compared to mean macular thickness 1st month after PRP and their changes were analysed. Macular thickness had further decreased at 3rd month when compared to that at 1st month and were highly significant. CONCLUSION PRP may cause transient changes in macular thickness in eyes with diabetic retinopathy associated with or without clinically significant macular oedema. The present study results suggest that macular oedema increased at 1 week in both the groups and decreased gradually at 1 month and 3 months. Greater rate of reduction of macular oedema was better appreciated in patients with clinically significant macular oedema.