[Examination of the retinal nerve fiber layer in diabetic retinopathy treated by argon laser panphotocoagulation].

PURPOSE To evaluate the alterations in the retinal nerve fiber layer in diabetic retinopathy treated by argon laser panphotocoagulation. METHODS Prospective study of patients with diabetic retinopathy submitted to retinal panphotocoagulation. Initially, complete ophthalmologic examination and optical coherence tomography were performed. All patients were submitted to panphotocoagulation with argon laser in one of the eyes. The retinal fiber layer was evaluated by means of optical coherence tomography in the first week, in the first, third and sixth months after treatment. RESULTS The sample was composed of 27 patients (27 eyes) with type 2 diabetes mellitus. The age varied from 41 to 64 years (mean of 53.7 +/- 6.2 years), with 10 (37%) males and 17 (63%) females. Regarding the retinopathy, 22.2% presented proliferative DR and 77.8% very severe non proliferative DR. There was a significant increase in the fiber layer thickness measurements, remaining in the temporal sectors, 3 and 4 hours, after 6 months of follow-up. Reduction of thickness was not observed in any of the analyzed parameters. CONCLUSIONS Reduction of the fiber layer thickness, identifiable by means of optical coherence tomography, in short and average term, was not observed in patients with diabetic retinopathy treated with panphotocoagulation. On the other hand, some sectors showed thickness increase during the follow-up.