Retinal Morphology Changes Following Intravitreal Aflibercept for Treatment-Resistant Neovascular Age-Related Macular Degeneration

Abstract

Purpose: To describe changes in retinal morphology in patients with persistent retinal exudation secondary to treatment-resistant exudative AMD following intravitreal aflibercept treatment.

Methods: 49 patients participating in a prospective clinical trial of intravitreal aflibercept for treatment-resistant neovascular AMD were assessed over 12 months. Participants received 3 loading doses of aflibercept monthly followed by further treatment every 2 months, and were reviewed monthly. Ophthalmic examinations included best-corrected visual acuity (BCVA) in Early Treatment of Diabetic Retinopathy Study (ETDRS) letters and spectral-domain optical coherence tomography (SD-OCT) to measure central macular thickness (CMT) and dimensions of intraretinal fluid (IRF) and subretinal fluid (SRF). Changes were assessed at each examination and compared to baseline.

Results: Mean BCVA at baseline was 60.5 letters, and a mean improvement of 4.7 was observed letters by month 12(p<0.001). Mean CMT at baseline was 439.5µm, and decreased by an average of 85.7µm by month 12 (p<0.001). Aflibercept achieved IRF resolution in 4 patients by month 12 with an average reduction in maximal IRF cyst diameter of 222.8µm compared to baseline (p<0.01). There was an average reduction in maximal SRF height of 53.7µm and maximal SRF width of 823.9µm at month 12 compared to baseline (p<0.001 for both), with SRF resolution occurring in 16 patients by month 12. When injection frequency was spaced from monthly to every 2 months, SRF recurred in between 11 and 16 patients, with an average increase of 50.3µm and 856.4µm for SRF height and width respectively when fluid recurred. IRF cyst diameter did not consistently increase with less frequent injections.

Conclusions: Intravitreal aflibercept was effective in improving both visual and anatomical outcomes in patients with previously treatment resistant neovascular AMD. Complete resolution of SRF occurred in a number of patients following treatment, and aflibercept therapy achieved improvements in morphological parameters relating to IRF and SRF. Spacing of injection frequency appears to be associated with an increase in SRF, however corresponding changes were not seen in IRF.

Keywords: 412 age-related macular degeneration • 466 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)