Luca De Simone, Anna Byszewska, Abdulrahman F Albloushi, Riccardo Genovese, Ioannis Papasavvas, Carl P Jr Herbort
Indocyanine green angiography (ICGA) represents an indispensable imaging modality for the precise evaluation and management of posterior uveitis by allowing to explore the choroidal compartment. ICGA leverages near-infrared fluorescence and extensive protein binding to provide an unhindered, dynamic assessment of the choriocapillaris and choroidal stroma. This review explores the principles, standard protocols, and clinical applications of ICGA in posterior uveitis. It details ICGA's critical role in classifying and diagnosing primary inflammatory choriocapillaropathies, like multiple evanescent white dot syndrome or serpiginous-like choroiditis, and stromal choroiditis, including Vogt-Koyanagi-Harada disease, birdshot chorioretinitis, and sarcoidosis. Furthermore, its utility in infectious uveitis, such as presumed intraocular tuberculosis and syphilitic chorioretinitis, is discussed. ICGA uniquely reveals subclinical choroidal lesions, such as hypofluorescent dark dots and geographic nonperfusion, which frequently exceed clinical or fluorescein angiography findings. By mapping the true extent of choroidal inflammatory activity, ICGA decisively guides the initiation and escalation or safe tapering of systemic corticosteroid and immunosuppressive therapies. Despite emerging noninvasive alternatives, ICGA cannot be fully replaced; it must be integrated into a multimodal imaging approach to optimize long-term visual outcomes and prevent irreversible structural damage in patients with complex chorioretinal inflammation.