Assessment of Choroidal Topographic Changes by Swept-Source Optical Coherence Tomography After Intravitreal Ranibizumab for Exudative Age-Related Macular Degeneration

Abstract

To investigate choroidal topographic changes by swept-source optical coherence tomography (Swept-OCT) in patients undergoing intravitreal injections of anti-vascular endothelial growth factor (VEGF) for exudative age-related macular degeneration (AMD). Prospective interventional study. Consecutive patients with unilateral treatment-naïve exudative AMD were entered into the study over 6 months. Changes in choroidal thickness after intravitreal ranibizumab injections, overall in the macula and in neovascular and non-neovascular areas, from baseline to month 3 (loading phase) and month 6 (pro re nata phase), were investigated by means of Swept-OCT maps. Forty-one eyes of 41 patients (mean age: 79.4 ± 7.3 years) were analyzed. Choroidal thickness at study entry was significantly thicker in the study eyes as compared to fellow eyes (P < .05). Analysis of sectorial choroidal thickness over time in study eyes revealed a significant reduction in both neovascular and non-neovascular areas from baseline to month 3 and month 6 (P < .0001 for all). Central choroidal thickness revealed significant variation between treated and fellow eyes from baseline to month 3 (P = .017) and month 6 (P = .045). The visual gain was significantly higher (P = .02) in patients with a larger choroidal thickness reduction (≥29 μm, n = 11) vs the others (n = 30). The thinning of the macular choroid (affected or not by choroidal neovascularization), along with the significantly thicker choroid in exudative AMD eyes before treatment initiation compared to fellow eyes, allows the hypothesis that anti-VEGF treatment may favorably influence the choroidal exudation by reducing choroidal vascular hyperpermeability.