title: Brain temperature and cerebral blood flow imaging in patients with severe subarachnoid hemorrhage: report of two cases.
abstract: BACKGROUND
  Temperature reversal, which is defined as observation of higher brain temperature than systemic temperature followed by lower brain temperature than systemic temperature, implies a poor prognosis in patients with severe subarachnoid hemorrhage (SAH). Serial regional cerebral blood flow (CBF) imaging using single-photon emission tomography (SPECT) was performed in 2 patients with severe SAH who showed temperature reversal.
  
  
  METHODS
  54-year-old woman and a 55-year-old man with severe SAH underwent ventricular drainage using a catheter that allowed monitoring of the brain temperature. SPECT imaging in these two patients showed that CBF was preserved before the occurrence of the temperature reversal and was exhausted afterwards. These patients died within 2 to 3 days.
  
  
  CONCLUSIONS
  Temperature reversal may indicate the exact time when absence of brain perfusion occurs, causing irreversible brain damage.
authors.affiliation: Department of Neurosurgery, Iwate Medical University, Morioka, Japan.
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Otawara
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Ogasawara
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Yukawa
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Tomitsuka
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kubo
authors.forename: Akira
authors.initials: A
authors.lastname: Ogawa
authors.forename: Michiyasu
authors.initials: M
authors.lastname: Suzuki
mesh_terms: D001831:Body Temperature / Q000502:physiology*; D001921:Brain / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015899:Tomography, Emission-Computed, Single-Photon