Patterns of retinal nerve fiber layer loss in patients with glaucoma identified by deep archetypal analysis

Glaucoma is a complex eye disorder characterized by an optic neuropathy usually leading to typical patterns of structural and functional loss. Current classification of glaucoma damage is predominantly subjective and qualitative. Determining precise glaucoma-induced patterns of structural and functional loss is clinically significant because different patterns of loss could differentially impact patient quality of life. Here, we develop and apply deep archetypal analysis (DAA) to over 2,500 samples of optical coherence tomography (OCT) images around the optic disc of about 278 eyes with glaucoma to discover patterns of structural loss. We show that deep DAA is an appropriate approach for discovering patterns on the convex hull that encloses data points in a high-dimensional space, and that this approach is resistant to outliers. We also present a novel visualization with potential utility in clinical applications for assessing structural damage in patients with glaucoma. Compared to classical archetypal matrix decomposition, DAA discovers outlier-resistant patterns. Unlike deep learning models, DAA generates interpretable outcomes with clinical relevance. Finally, 16 discovered patterns of RNFL loss are visualized and clinically validated by glaucoma experts. Such patterns may serve as basic elements to quantify high-dimensional RNFL data in different applications.