title: Early diagnosis of cerebral ischemia in cerebral vasospasm by oxygen-pulse near-infrared optical topography.
abstract: OBJECTIVE
  Early diagnosis of vasospasm is a key factor in the choice of treatment after subarachnoid hemorrhage (SAH). However, a noninvasive method of diagnosing delayed ischemic neurological deficit (DIND) has not been established. We therefore propose a new method of diagnosing cerebral ischemia using near-infrared optical topography (OT) with oxygen inhalation.
  
  
  METHODS
  We used a 44-channel OT system that covers the bilateral front otemporoparietal areas to assess 29 patients who underwent surgery within 72 h of the onset of SAH. The patients inhaled room air followed by oxygen for 2 min, and then peripheral oxygen saturation (SpO₂) was continuously monitored at the index fingertip. The patients were assessed by N-isopropyl-p-[¹²³I]iodoamphetamine (IMP)-SPECT and OT on the same day. Ischemic findings were confirmed using principal component analysis with reference to the systemic SpO₂value.
  
  
  RESULTS
  Seven of 29 patients developed DIND. Evidence of ischemia was identified by OT in all seven of these patients before the onset of DIND. The OT and SPECT findings agreed in 27 (93 %) of the 29 patients.
  
  
  CONCLUSIONS
  Our method might detect cerebral ischemia before the onset of DIND and thus be clinically useful for assessing cerebral ischemia with vasospasm.
authors.affiliation: Department of Neurosurgery, Jichi Medical University Saitama Medical Center, Saitama-Ken, Japan, chinu@jichi.ac.jp.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Akira
authors.initials: A
authors.lastname: Ebihara
authors.forename: Masashi
authors.initials: M
authors.lastname: Ikota
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Yamaguro
authors.forename: Haruna
authors.initials: H
authors.lastname: Kamochi
authors.forename: Gen
authors.initials: G
authors.lastname: Kusaka
authors.forename: Mami
authors.initials: M
authors.lastname: Ishikawa
authors.forename: Takehiko
authors.initials: T
authors.lastname: Konno
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Mashiko
authors.forename: Eiju
authors.initials: E
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D010092:Oximetry / Q000379:methods*; D010100:Oxygen / Q000097:blood; D012189:Retrospective Studies; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon; D020301:Vasospasm, Intracranial / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes; D010100:Oxygen