Brain temperature and cerebral blood flow imaging in patients with severe subarachnoid hemorrhage: Report of two cases

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. CASE DESCRIPTION 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. (C) 2003 Elsevier Inc. All rights reserved.