Pathways to Patchy Atrophy in High Myopia: Precursor Patterns, Structural Characteristics, and Long-Term Outcomes

ABSTRACT Introduction To characterize distinct precursor patterns associated with the development of patchy atrophy (PA) in highly myopic eyes and to describe their structural evolution and clinical outcomes over time. Design Retrospective multicenter cohort study. Participants Highly myopic patients with documented onset of PAs and at least 3 months of multimodal imaging (MMI) prior to the PA development. Methods Clinical, demographic, and MMI findings were retrospectively collected from three tertiary referral centers. Based on MMI findings preceding PA onset, eyes were categorized into three patterns: 1) inflammatory PAs in the context of punctate inner choroidopathy (PIC); 2) neovascular PAs, associated with extrafoveal macular neovascularization (MNV); and 3) idiopathic PAs, in the absence of identifiable inflammatory or neovascular precursor lesions. Main Outcome Measures Precursor patterns, clinical and MMI characteristics, clinical complication profile, and atrophy growth rate (AGR). Results The study included 103 eyes (84 patients; 28 [27%] men) with a mean (SD) age of 62 (13.4) years and mean refractive error of –13.2 (5.8) diopters at PA onset. Median observation periods prior to PA onset and post-PA follow-up were 2.1 years (IQR 5.20) and 3.44 years (IQR 7.23), respectively. Inflammatory PAs were detected in 33 (32%) eyes, neovascular PAs in 9 (9%) eyes, and 61 eyes (59%) had idiopathic PAs. Number of pre-existing PAs at baseline was highest in inflammatory PAs (6.1±6.4), followed by neovascular PAs (1.6±1.1) and idiopathic PAs (1.5±1.1; p<0.001). Late-stage complications, including MNV (p<0.001), subretinal fibrosis (p<0.001), and macular atrophy (p=0.01), occurred more frequently in inflammatory and neovascular PA than in idiopathic PA. Exploratory tree-based analysis identified baseline lesion number as a key feature distinguishing inflammatory PAs from idiopathic PAs. Mean AGR in the overall cohort was 0.73±1.06 mm²/year (95% CI, 0.52–0.94), with progression fastest in inflammatory PAs (1.3±1.4 mm²/year), followed by neovascular PAs (0.7±0.7 mm²/year) and slowest in idiopathic PAs (0.4±0.7 mm²/year; p<0.001). Higher baseline lesion number was associated with faster AGR (p=0.005). Conclusions PAs in highly myopic eyes develop with three precursor patterns (inflammatory, neovascular and idiopathic) and differ in structural characteristics, atrophy progression, and complication profile. Recognition of PA patterns may improve clinical assessment of highly myopic eyes.