Association of Ellipsoid Zone, External Limiting Membrane Disruption and Disorganization of Retinal Inner Layers as Retinal Imaging Biomarkers by Spectral Domain Optical Coherence Tomography (SD-OCT) in Diabetic Macular Edema

Context: There are several spectral domain optical coherence tomography biomarkers in diabetic macular edema. These are disorganization of the retinal inner layers (DRIL), ellipsoid zone and external limiting membrane disruption. Further studies are required to evaluate these retinal imaging biomarkers. Aims: To determine the role and advantages of these biomarkers and their association with visual outcome after treatment or normal follow up in patients of diabetic macular edema. Settings and Design: Prospective and interventional study was conducted from January 2021 to December 2021. Methods and Material: Optical coherence tomography scan was carried out in 50 eyes of 50 patients of diabetic macular edema out of which disorganization of retinal inner layers were found in eyes 28 eyes (56%) and ellipsoid zone and external limiting membrane disruption was found in 35 eyes(70%) and they were given 0.05 ml of ranibizumab monthly injection for consecutive 3 months. Statistical analysis: IBM.SPSS statistics software 23/0 version was used. To find the significance in categorical data Chi-square test was used and in the multivariate analysis the one way ANOVA with Tukey's Post-Hoc test was used. Results: In our study we found that ellipsoid zone , external limiting membrane disruption and horizontal extent of disorganisation of retinal inner layers directly proportional to the decrease in visual acuity(p=0.001less than0.05) , (p=0.012less than0.05), (p=0.006less than0.05) respectively also the horizontal extent of disruption had decreased after injecting 3 monthly intravitreal ranibizumab . In statistics probability value 0.05 is considered as significant level. Conclusion: Final visual outcome depends on these imaging biomarkers.