A 15-year-old boy had temporary hypertropia, supraduction deficit, ipsilateral mydriasis, and accommodative paresis after bilateral endoscopic ethmoidectomy, bilateral partial inferior turbinectomy, septoplasty, and Caldwell-Luc procedures for chronic sinusitis. Postoperative imaging did not disclose any intra-orbital abnormalities. The patient was treated with oral prednisolone 70 mg/day on a tapering schedule. Within two months, the ophthalmic abnormalities had resolved. This is the second report to describe such findings., which are attributed to damage of the inferior division of the third cranial nerve secondary to manipulation of adjacent ethmoid tissues.