Defects in macular‐retinal layer analysis of glaucoma patients compared to normative database

Abstract

AbstractPurpose High‐resolution optical coherence tomography (HR‐OCT) enables a quantitative analysis of the configuration of retinal layers. The aim of this study was to analyze the topographic distribution of pathologic thinning of specific macular retinal layers of glaucoma patients.Methods Macular 3D‐scans were recorded with HR‐OCT (Cirrus®, Carl Zeiss Meditec). Retinal layers, especially the retinal nerve fiber layer (RNFL) and the retinal ganglion cell plus inner plexiform layer (RGIPL), were automatically segmented with a custom made software (Matlab R2009b®, The Mathworks Inc.). A normative database for the thickness of the RNFL, the RGIPL and the retina was created using healthy subjects (n=84) taking into account for the effects of age. 18 glaucoma patients were compared to the 95% confidence interval of the normative database using the thickness values of RNFL, RGIPL and retina within 65 segments.Results On average the glaucoma patients showed for RNFL, RGIPL and retina 29.8, 49.4 and 53.9 pathologic segments within the macula. The minimum number of pathologic segments per patient was 5, 24 and 29. The average thickness values for healthy subjects were 32.95 µm (RNFL), 79.02 µm (GCIPL) and 321.46 µm (retina), for glaucoma patients 24.85 µm, 57.46 µm and 281.30 µm, respectively.Conclusion In our study quantitative analysis of retinal layer thickness based on macular HR‐OCT showed a decrease of RNFL, RGIPL and retinal thickness in glaucoma patients. Within our sample all patients had several pathologic segments for all of the analyzed retinal layers. In most of the cases those segments were clustered. Further studies including larger numbers of patients to confirm our findings are advisable.