Near-Infrared Autofluorescence in Non-Infectious Uveitis: A Review

This review offers a comprehensive synthesis of current evidence on near-infrared autofluorescence (NIR-AF) in non-infectious uveitis, highlighting its strengths, limitations, and role in diagnosis, monitoring, and understanding disease mechanisms. Unlike blue-light autofluorescence, which mainly detects lipofuscin, NIR-AF visualizes melanin and related compounds in the retinal pigment epithelium (RPE) and choroid, providing deeper penetration, reduced phototoxicity, and greater comfort. Across entities like Vogt-Koyanagi-Harada disease, MEWDS, punctate inner choroidopathy, APMPPE, and Fuchs' heterochromic iridocyclitis, NIR-AF reveals patterns often invisible on conventional imaging-detecting subclinical lesions, differentiating active from inactive disease, and tracking RPE changes over time. Its persistence in showing hypoautofluorescent or hyperautofluorescent lesions after clinical resolution offers unique insight into residual or subclinical inflammation. The technique complements OCT, fluorescein, and indocyanine green angiography, adding a melanin-specific layer to multimodal imaging. Limitations include a weaker signal compared to BL-AF, susceptibility to media opacities, equipment-dependent variability, and lack of standardized interpretation criteria. While it cannot quantify choroidal melanin loss directly and image acquisition can be challenging, its non-invasive, repeatable nature and diagnostic yield make it a promising tool for longitudinal uveitis care. Further prospective studies, standardization, and AI-driven analysis could expand its clinical impact, potentially cementing NIR-AF as an essential component in uveitis imaging strategies.