Orbital myositis as the cause of palsy of the extraocular rectus muscle is reported in 7 children presenting with acute ocular pain at the Scottish Rite Children’s Hospital, Atlanta, GA. All had chemosis and erythema of the conjunctiva restricted to the quadrant overlying the involved muscle. All had ocular pain and some had redness and swelling of the lids with ptosis. All were afebrile. The diagnosis was confirmed by CT demonstration of an enlarged lateral rectus muscle. All had a benign course and were immediately responsive to corticosteroids. A recurrence in 2 patients was attributed to abrupt withdrawal of steroids. 
COMMENT. The differential diagnosis includes orbital cellulitis which is distinguished by fever and response to antibiotics. Reported isolated causes of orbital myositis include Lyme disease, cysticercosis, and a paraneoplastic syndrome.