A childhood cavernous conundrum.

A 9-year-old boy presented with a left-sided "tooth ache." Subsequently, he developed new onset vertical diplopia. He was found to have a left cranial nerve three palsy. Cranial magnetic resonance imaging showed bilateral cavernous sinus lesions that were initially interpreted as possible "cavernous sinus thrombosis." Subsequent blood smear and bone marrow biopsy disclosed Burkitt lymphoma. He was treated with chemotherapy and made a dramatic recovery. Burkitt lymphoma rarely presents with a third nerve palsy but should be considered in the differential diagnosis of childhood cavernous sinus syndrome.