title: Extra-axial posterior fossa lesions simulating intra-axial lesions on computed tomography.
abstract: Differentiation of extra- from intra-axial posterior fossa lesions is sometimes not possible on computed tomography. Six cases are presented wherein the lesion appeared to be intra-axial on computed tomograms yet angiographically and surgically proved to be extra-axial. False localization on computed tomography occurs with slowly growing masses which burrow into brain parenchyma.
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000000981:diagnostic imaging*; D003388:Cranial Fossa, Posterior; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed