Anatomical outcomes of patients receiving 50 or more intravitreal anti-VEGF injections for neovascular age-related macular degeneration

Abstract

Purpose : The aim of this study was to analyze optical coherence tomography (OCT) scans of patients receiving long-term anti-vascular endothelial growth factor (VEGF) therapy for neovascular age-related macular degeneration (nAMD) by comparing anatomical features at start of treatment to the time of their 50^thinjection.

Methods : This is a retrospective cohort study with data extracted from the Moorfields Eye Hospital Electronic Medical Record system with inclusion criteria being eyes receiving ≥ 50 injections for choroidal neovascularization secondary to nAMD between 2008-2017. Either ranibizumab or aflibercept was used as anti-VEGF therapy. Both baseline and the 50^thinjection OCT were analyzed. Morphometric analysis was performed manually to obtain central retinal thickness (CRT), measured from inner retinal surface to Bruch’s membrane. Comparative analyses of paired, non-parametric data and categorical data were carried out with Wilcoxon Signed Rank test and Chi-squared proportional testing, respectively. Distribution of data was tested for normality using the Shapiro-Wilk test and level of statistical significance set at 0.05.

Results : One-hundred eyes had ≥ 50 anti-VEGF injections. Of these, 33% had central intraretinal fluid (IRF) and 75% had central subretinal fluid (SRF) at presentation. At the 50^thinjection, these values decreased to 27% (p-value 0.396) and 42% (p<0.001), respectively. Both drusen (88% at both time points) and pigment epithelial detachment (PED) (88% at baseline and 87% at 50^thinjection) persisted in the majority of eyes. Ill-defined subretinal hyperreflective material (SHRM) was detected in 20% of the eyes at baseline and 3% at 50^thinjections (p-value 0.002). In contrast, well-defined SHRM was detected in 7 and 6 eyes at the two time points, respectively. Presence of vitreomacular adhesion causing central deformation was similar at presentation and at 50^th injections, while epiretinal membrane increased from 3% to 8% of eyes. Mean CRT decreased from 372.2±220.68μm (standard deviation) at baseline to 283.96±154.6μm at 50^thinjections (p<0.001).

Conclusions : Characterizing long-term morphological sequelae is crucial to understand treatment efficacy and response. Repeated anti-VEGF injections for nAMD induces significant reduction in SRF and overall central retinal thickness. IRF and PED were comparable at baseline and at the 50^thinjection.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.