title: Giant intracranial aneurysm presenting as a posterior fossa mass.
abstract: A patient with signs of brainstem compression and hydrocephalus is reported. The clinical picture suggested a posterior fossa neoplasm. Computed tomography, however, proved highly accurate in making the diagnosis of a giant, partially thrombosed vertebrobasilar aneurysm. The radiographic appearance of this entity is summarized and pathologic correlation is offered.
mesh_terms: D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000473:pathology; D001932:Brain Neoplasms / Q000000981:diagnostic imaging*; D003388:Cranial Fossa, Posterior; D003937:Diagnosis, Differential; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000473:pathology