Thyroid-related orbitopathy. (A) 35-year-old male developed bilateral acute orbital cellulitis as initial onset of thyroid-related orbitopathy. Lateral cantholysis and pulsed intravenous corticosteroids compromised initial therapy. (B) Axial CT demonstrates proptosis and moderate enlargement of medial rectus muscle belly. (C) After 1 week of corticosteroid therapy, inflammation decreased significantly. Corticosteroids were tapered over a 3-month period. (D) 1 year later, well after corticosteroids were discontinued, patient demonstrates minimal inflammation; no surgery was required.