Introduction: Non-specific orbital inflammation (NSOI), formerly known as idiopathic orbital inflammatory disease (IOID), is a rare, exclusion-based orbital disorder with diverse clinical manifestations. This study evaluates the demographic patterns, clinical features, histopathological profiles, and treatment outcomes of NSOI cases managed at a tertiary referral centre in Malaysia.
Materials and methods: A six-year retrospective review was conducted at a tertiary referral centre in northern Malaysia, involving 36 patients diagnosed with NSOI between January 2018 and December 2023. Diagnosis was based on clinical features, exclusion of systemic and infectious causes through serology, and supportive imaging or biopsy findings. Only cases with histopathological confirmation and immunohistochemical staining negative for lymphoma, carcinoma, and other malignancies were included. Data included demographics, clinical presentation, imaging and histopathological findings, serologic evaluations, and treatment modalities. Outcomes were assessed based on symptom resolution, radiologic improvement, recurrence, and treatment response.
Results: Most patients were male (61.1%), with a mean age of 43.6 years. Unilateral involvement predominated (77.8%). Common presentations included periorbital swelling (69.4%), ophthalmoplegia (22.2%), conjunctival mass (22.2%), and proptosis (19.4%). Imaging revealed frequent involvement of the lacrimal gland (45.8%), extraocular muscles (37.5%), and conjunctiva (37.5%). The main histopathological findings included reactive lymphoid hyperplasia (40%), granulomatous inflammation (20%), and chronic inflammation (23.3%). Of the 36 patients, 19 received medical treatment, with 84.2% given systemic corticosteroids, while the remaining 17 patients were managed conservatively without any medical treatment, and they remained clinically stable throughout follow-up with no evidence of disease progression. Among treated cases, recurrence occurred in 25%, predominantly in males.
Conclusion: NSOI shows varied clinical and anatomical patterns. Corticosteroids remain the mainstay of treatment, but conservative management is appropriate in stable, nonprogressive cases when close monitoring and diagnostic exclusion are assured. These findings support individualised therapeutic strategies and long-term followup.