Anti-Vegf therapy leads to an improvement in grade of retinal pigment epithelium alterations on single layer retinal pigment epithelium map in diabetic macular edema

Abstract

Purpose In bovine retinal pigment epithelium (RPE) cells, increased secretion of vascular endothelial growth factor (VEGF) has a positive linear association with proliferation of RPE. Spectral domain optical coherence tomography (SD-OCT) based improvement in grades of topographic retinal pigment epithelium alterations (RPE-A), were evaluated after intravitreal anti-VEGF therapy, in diabetic macular edema (DME), for the first time. Methods A tertiary care center-based, prospective study. Forty-four consecutive patients, 40–65 years of age with type 2 diabetes mellitus (DM) with DME, were administered three doses of anti-VEGF therapy at monthly intervals. Pre- and post-intervention SD-OCT was done and central sub field thickness (CST), cube average thickness (CAT) and topographic grades of RPE-A were assessed using single layer RPE map (SL-RPE) as; Grade 0: No alterations, Grade 1: Alteration in two quadrants, Grade 2: Alteration in more than two quadrants. Results CST decreased from 354.2 ± 16.0 µm pre-intervention to 233.2 ± 7.9 µm post-intervention. CAT reduced from 340.6 ± 6.5 µm pre-intervention to 274.1 ± 5.1 µm post-intervention. Significant improvement in grades of RPE-A pre- v/s post-intervention were observed. (Grade 0: 0 v/s 39; Grade 1: 17 v/s 3; Grade 2: 27 v/s 2) (p < 0.001). Conclusion Anti-VEGF therapy is associated with an improvement in grades of RPE-A in DME. The study was registered with the Clinical Trial Registry of India (CTRI/2019/03/018135).