title: Massive subependymal hemorrhage caused by an occult vascular malformation--two case reports.
abstract: Two patients presented with massive subependymal hemorrhage caused by vascular anomalies occult to angiography, computed tomography (CT) scanning, and magnetic resonance (MR) imaging. A 47-year-old male initially presented with a headache and became comatose 3 weeks later. CT and MR imaging demonstrated a massive hematoma in the right caudate head projecting into the lateral ventricle. A 60-year-old male sustained heaviness of his left extremities 8 days prior to admission and his condition gradually deteriorated. Neuroimaging revealed a right thalamic hematoma adjacent to the lateral ventricle. Cerebral angiography, CT, and MR imaging failed to detect any vascular anomaly. The hematomas increased in size gradually and were surgically explored. The histological diagnosis was arteriovenous malformation for the first case and cavernous angioma for the second case that had ruptured repeatedly. These cases were unique in the unusual location in the subependyma, and diagnostic neuroimaging modalities could not disclose the vascular anomalies, and the hematomas enlarged progressively to become critically symptomatic. Surgical intervention is mandatory for mass reduction and correct diagnosis of such lesions, with favorable outcome as long as the surgery is not delayed until too late.
authors.affiliation: Department of Neurosurgery, Kitano Medical Research Institute and Hospital, Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kobata
authors.forename: A
authors.initials: A
authors.lastname: Kondo
authors.forename: K
authors.initials: K
authors.lastname: Iwasaki
authors.forename: I
authors.initials: I
authors.lastname: Hattori
mesh_terms: D002421:Caudate Nucleus / Q000098:blood supply* / Q000000981:diagnostic imaging; D002533:Cerebral Angiography; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging / Q000209:etiology*; D002908:Chronic Disease; D006392:Hemangioma, Cavernous / Q000150:complications* / Q000175:diagnosis*; D006406:Hematoma / Q000000981:diagnostic imaging; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000150:complications* / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome