Nonspecific Idiopathic Orbital Inflammation Update

胡佩欣 Pei-Shin HuTaiwan Speaker Nonspecific Orbital Inflammation UpdateNonspecific orbital inflammation (NSOI) remains one of the most challenging diagnostic entities in orbital disease due to its heterogeneous presentation and overlap with infectious, autoimmune, and neoplastic conditions. Traditionally considered a diagnosis of exclusion, NSOI now benefits from emerging imaging criteria, structured diagnostic algorithms, and increasing evidence supporting individualized management. This presentation integrates data from recent guideline development and a large evidence-based clinical cohort to provide a concise and practical framework for clinicians. Key components include updated classification systems, the role of MRI with diffusion-weighted imaging in differentiating NSOI from lymphoma or IgG4-related disease, and indications for biopsy when clinical or radiologic features are atypical or treatment response is inconsistent. Treatment strategies emphasize corticosteroid response patterns, recurrence predictors, and escalation pathways incorporating immunosuppressants, biologics such as rituximab, and selective radiotherapy. By combining high-level evidence with annotated imaging examples and treatment algorithms, this lecture aims to support accurate diagnosis, avoid misclassification, and improve long-term outcomes in patients with NSOI, especially those with recurrent or steroid-dependent disease.