The Spectrum of Choroiditis: Clinical Phenotypes, Multimodal Imaging, and Etiologies

Choroiditis represents a heterogeneous group of posterior uveitic disorders primarily affecting the choroid. Historically, its terminology has been inconsistent due to overlapping clinical phenotypes and evolving understanding from multimodal imaging. With the advent of indocyanine green angiography (ICGA), choroiditis is now broadly classified into choriocapillaritis and stromal choroiditis, each encompassing distinct clinical entities of infectious and non-infectious etiologies.

Recent literature was reviewed to summarize advances in the diagnosis, imaging features, etiological classification, and management of choroiditis. The review focuses on the clinical and imaging characteristics of major entities-serpiginous choroiditis (SC), serpiginous-like choroiditis (SLC), multifocal choroiditis (MFC), punctate inner choroiditis, Vogt-Koyanagi-Harada disease (VKH), sympathetic ophthalmia (SO), birdshot chorioretinopathy, sarcoid choroiditis, and tubercular choroiditis-with emphasis on the role of ICGA in differentiating choriocapillaritis from stromal choroiditis.

Clinical presentations vary according to etiology, ranging from painless visual disturbances in autoimmune SC to inflammatory foci in infectious SLC and multifocal serpiginoid choroiditis (MSC). ICGA remains the cornerstone in assessing choroidal involvement and detecting subclinical lesions. Laboratory investigations should be phenotype-driven and directed toward ruling out tuberculosis and sarcoidosis in endemic regions. Management is disease-specific. Corticosteroids remain the mainstay for most entities, while immunosuppressants and biologics are used for refractory or recurrent cases. Infectious choroiditis such as tubercular or fungal etiologies requires targeted antimicrobial therapy, often combined with corticosteroids. Early introduction of immunosuppressive therapy in chronic entities like VKH and SO significantly improves visual outcomes.

Choroiditis encompasses a spectrum of inflammatory disorders with overlapping clinical features but distinct pathogenetic mechanisms. Accurate diagnosis requires integration of clinical phenotype, imaging, and systemic evaluation. Tailored treatment strategies-guided by underlying etiology-are crucial for disease control and vision preservation. Maintaining a high index of suspicion for infectious causes remains essential, particularly in tuberculosis-endemic settings.