Abstract
Purpose :
In nAMD, SHRM is considered an important optical coherence tomography (OCT) biomarker, and full SHRM resolution under antiangiogenic treatment has been associated with improved visual outcome compared to persistent SHRM. This post hoc study aims to identify baseline OCT features associated with SHRM resolution by month 6.
Methods :
97-line OCT volume scans (Heidelberg Spectralis) of 108 nAMD study eyes from the Day 1 (treatment-naive) and month 6 (after Aflibercept treatment) visits of the biomarker study LONGITUDE (EudraCT number: 2020-003515-10) were retrieved post hoc and all available volumes were manually graded into SHRM resolution vs. persistence (see examples in Fig. 1). All Day 1 scans were automatically segmented with a DL segmentation model (published previously), generating 104 OCT features. The medians of selected baseline OCT features of SHRM, pigment epithelial detachment (PED), subretinal fluid (SRF) and intraretinal fluid (IRF), measured in the ETDRS 3 mm diameter area, were compared. A decision tree model was fitted on all segmentation data using majority voting at each split (rpart maxsurrogate=0), with hyperparameters selected by 10-fold cross-validation.
Results :
Of the 108 eyes included, 70 had SHRM at baseline. 22 of those showed full SHRM resolution by month 6 and tended to have a lower baseline SHRM median volume (112 nl), area (1.5 mm2), maximum width (1520 μm) and maximum height (250 μm), compared to the 48 eyes with persistent SHRM (226 nl, 2.6 mm2, 2125 μm and 292 μm, respectively); moreover, those 22 eyes had a lower baseline IRF mean volume (0.1 vs. 0.3 nl), and higher PED (244 vs. 162 nl) and SRF (94 vs. 37 nl) mean volumes. The selected decision tree model had a sensitivity of 0.917, specificity of 0.636 and AUROC of 0.795 on the training set, and showed that SHRM resolution was most likely in eyes with a SHRM volume < 204 nl and a maximum PED height ≥ 174 μm at baseline (Fig. 2).
Conclusions :
SHRM that fully resolves tends to be smaller and associated with higher volumes of PED and SRF, and with lower volumes of IRF at baseline. Also according to the decision tree model, SHRM resolution seems to be more likely in eyes with lower SHRM volume and a larger maximum PED height. These findings may reflect that SHRM resolves more often in macular neovascularization type 1 and 3 than in type 2.
This abstract was presented at the 2024 ARVO Imaging in the Eye Conference, held in Seattle, WA, May 4, 2024.