title: Case report: acute subdural hematoma due to angiographically unvisualized ruptured aneurysm.
abstract: BACKGROUND
  We report a case of acute subdural hematoma (SDH) due to angiographically unvisualized ruptured aneurysm.
  
  
  METHODS
  A 57-year-old man presented with sudden-onset headache and nausea. Computed tomography revealed right acute SDH and cerebral angiography revealed no abnormal vessels, but at operation, we found an aneurysm arising from the precentral artery causing an acute SDH.
  
  
  CONCLUSIONS
  In a case of spontaneous acute SDH, the possibility of a cortical artery aneurysm should be considered even if no aneurysm is recognized at angiography.
authors.affiliation: Department of Neurosurgery, Toyama Medical and Pharmaceutical University, Toyama 930-0194, Japan. ehori-tym@umin.ac.jp
authors.forename: Emiko
authors.initials: E
authors.lastname: Hori
authors.forename: Tsuneaki
authors.initials: T
authors.lastname: Ogiichi
authors.forename: Nakamasa
authors.initials: N
authors.lastname: Hayashi
authors.forename: Naoya
authors.initials: N
authors.lastname: Kuwayama
authors.forename: Shunro
authors.initials: S
authors.lastname: Endo
mesh_terms: D000208:Acute Disease; D017542:Aneurysm, Ruptured / Q000150:complications*; D002533:Cerebral Angiography; D005188:False Negative Reactions; D006408:Hematoma, Subdural / Q000209:etiology*; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications*; D008297:Male; D008875:Middle Aged