Efficacy of Periocular and Orbital Steroid Injection in Active Thyroid Eye Disease Affecting Extraocular Muscles: A Systematic Review

Introduction: Thyroid eye disease (TED) is an autoimmune inflammatory orbital disorder in which extraocular muscle involvement commonly leads to motility restriction and diplopia. Systemic corticosteroids are effective but often limited by adverse effects, prompting interest in localized steroid delivery. Objective: To systematically review the clinical outcomes of periocular and orbital steroid injection in patients with active TED and extraocular muscle involvement. Methods: A systematic search of PubMed, the Cochrane Library, and ScienceDirect was conducted in accordance with PRISMA guidelines. Studies evaluating periocular or orbital steroid injection in active TED with extraocular muscle involvement were included. Outcomes of interest were Clinical Activity Score, proptosis, extraocular muscle motility, and diplopia. Due to clinical and methodological heterogeneity, a qualitative narrative synthesis was performed. Results: Eight studies were included in the qualitative synthesis. Periocular and orbital steroid injection consistently reduced inflammatory activity across studies. Improvements in proptosis were modest and inconsistently reported. Extraocular muscle motility and diplopia outcomes were heterogeneous, with partial improvement or stabilization observed in a subset of patients, particularly those with shorter disease duration. Discussion: Local steroid injection provides effective suppression of orbital inflammation but demonstrates variable impact on structural and functional outcomes. The degree of response appears influenced by disease stage, assessment methods, and treatment protocols. Conclusion: Periocular and orbital steroid injection is a viable local treatment option for active TED with extraocular muscle involvement, offering reliable inflammation control and potential functional benefit in selected patients.