A large expansile lesion is noted in the right petrous apex, hyperintense on both T1- and T2-weighted scans, without diffusion restriction or internal contrast enhancement. The imaging findings are characteristic, with one exception – that a peripheral hemosiderin rim is not present. The lesion was resected through a transnasal, transclival route.

Part of the on-line supplement to Neuroradiology – The Essentials with MR and CT (© 2015)