Abstract
Abstract: :
Purpose: To evaluate peripapillary retinal nerve fiber layer (RNFL) in diabetic patients with and without diabetic retinopathy (DR) . Methods: 120 diabetic patients were enrolled in this prospective study. Each patient underwent: visual acuity quantification (ETDRS chart, logMAR notation), seven standard fundus photographs to grade diabetic retinopathy, and RNFL thickness measured with optical coherence tomography (OCT Model 3000, Zeiss, Jena, Germany). Ocular hypertension, glaucoma, previous retinal photocoagulation, pathologic myopia, and central nervous system disorders were exclusion criteria. Forty normal subjects were used as controls. Results: Out of 120 diabetic patients, 90 had diabetic retinopathy (75 non proliferative and 15 proliferative DR) and 30 were free of retinopathy. RNFL progressively decreased in thickness from no retinopathy level toward proliferative DR (92.6 ± 34.6 µ vs 62.3 ± 30.8, p< .002). RNFL thickness homogeneously decreased around the optic nerve. Conclusions: Diabetes affects not only retinal vasculature, but also retinal neuronal and glial cells. This study demonstrates that retinal neuronal cells, more precisely retinal ganglion cells, decrease in diabetes. This pathologic process is present even when retinopathy, when considered a pure retinal vascular disorder, is still absent.
Keywords: diabetic retinopathy • ganglion cells • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)