title: Hemorrhage and abnormal veins in acoustic neurinoma: MR findings.
abstract: We reviewed the MR imaging findings of 57 acoustic neurinomas which were verified at surgery or diagnosed on the basis of neuroradiological and neurootological data. Two uncommon MR findings of acoustic neurinoma were found. First, hypointense areas were observed on T2-weighted images in five of the 12 tumors larger than 25 mm in diameter. These hypointense areas represented hemosiderin deposition secondary to occult intratumoral hemorrhage. Second, curvilinear or round signal voids were noted at the periphery of 11 large or medium-sized tumors, and these corresponded to "abnormal veins" seen on angiographic studies.
authors.affiliation: Department of Radiology, Tohoku University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ishii
authors.forename: S
authors.initials: S
authors.lastname: Takahashi
authors.forename: K
authors.initials: K
authors.lastname: Matsumoto
authors.forename: T
authors.initials: T
authors.lastname: Ishibashi
authors.forename: K
authors.initials: K
authors.lastname: Sakamoto
authors.forename: S
authors.initials: S
authors.lastname: Hashimoto
authors.forename: R
authors.initials: R
authors.lastname: Katakura
authors.forename: A
authors.initials: A
authors.lastname: Ogawa
authors.forename: R
authors.initials: R
authors.lastname: Yuasa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004428:Ear Neoplasms / Q000098:blood supply / Q000150:complications / Q000175:diagnosis*; D006470:Hemorrhage / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000098:blood supply / Q000150:complications / Q000175:diagnosis*; D010690:Phlebography; D014680:Veins / Q000002:abnormalities; D000159:Vestibulocochlear Nerve / Q000473:pathology*