Abstract
Purpose :
Treating neovascular age-related macular degeneration (nAMD) often starts with intensive therapy with anti-vascular endothelial growth factor (VEGF) injections. In prior post-hoc studies, early residual fluid (ERF), defined as intraretinal fluid (IRF) and/ or subretinal fluid (SRF) after the loading dose, was associated with poorer long-term visual acuity. This retrospective study examined the impact of ERF on visual acuity using a machine learning (ML) algorithm to quantify fluid on optical coherence tomography (OCT) in routine clinical practice.
Methods :
286 treatment naïve patients with nAMD were identified from a retrospective analysis. Only one eye was included per patient. Best visual acuity (BVA) (ETDRS letters) and OCT data were collected every 3 months from baseline to 12 months. OCTs were analyzed by the Notal OCT analyzer ML algorithm, quantifying IRF, SRF, and total retinal fluid (TRF). The ERF group was defined as those with fluid at week (W) 12. Fluid type at W12 was stratified and volumes were divided into quartiles to see their predictive value for W52 BVA. Paired t-tests and ANOVA compared BVA and fluid changes within and between fluid subgroups.
Results :
At W12, 58.4% of patients had ERF. The breakdown of subgroups at W12 were no fluid (41.6%), IRF-only (21.6%), SRF-only (45.5%), and IRF & SRF (32.9%). When comparing long term BVA outcomes according to W12 fluid status, ERF and ERF-free groups had similar mean BVA gains from baseline to W52 (+5.70±15.44 vs. +4.89±17.95; p= 0.69). There was also no significant difference in mean BVA gains from baseline to W52 when comparing the W12 fluid subgroups of no fluid (+4.89±17.95), IRF-only (+4.56±16.36 ), SRF-only (+5.55±12.49), and IRF & SRF (+6.61±18.45), p=0.93. Quartile analysis of W12 IRF, SRF, and TRF quantities revealed no predictive pattern for W52 BVA.
Conclusions :
These results from routine clinical practice diverge from prior post-hoc studies, since there was no significant difference in long-term BVA gains between W12 ERF and ERF-free cohorts, as well as between the various fluid subgroups. In addition, fluid quantifications of ERF did not appear clinically relevant when predicting long term BVA. Thus, the clinical utility of a ML algorithm for predicting visual outcomes of ERF cohorts in nAMD warrants further exploration.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.