Orbital pseudotumour presenting as orbital cellulitis.

A 33-year-old woman presented to a community emergency department with a 4-day history of monocular orbital pain, photophobia and pain on extraocular movement. Findings included chemosis, conjunctival injection and restricted extraocular movements causing strabismus. She was diagnosed with orbital cellulitis during her initial emergency department visit and treated with intravenous antibiotics. On her second ED visit later the same day, a diagnosis of orbital pseudotumour was made after computed tomography revealed inflammation of the sclera, optic nerve, muscle and adipose tissue within the orbit. Antibiotics were discontinued and tapering steroids were initiated, with prompt resolution of symptoms.