title: [Measurement of cerebrovascular reserve of patients with symptomatic middle cerebral artery ischemia by perfusion CT and combined with CO2 test].
abstract: OBJECTIVE
  To investigate the feasibility of assessment of the cerebrovascular reserve (CVR) by perfusion CT combined with CO(2) test in patients with symptomatic middle cerebral artery ischemia.
  
  
  METHODS
  38 healthy volunteers and 32 symptomatic middle artery ischemia inhaled mixed gas of 5% CO(2) and 95% O(2), and the changes of CO(2) concentration by the end of inhalation were measured among as pretest. Ten-row CT was with round area 24 mm in diameter at bilateral blood supply areas of middle cerebral artery as ROI. Forty patients with symptomatic middle cerebral artery ischemia underwent perfusion CT with 5% carbon dioxide and 95% oxygen. The end-expiratory CO(2) content after inhalation of mixture gas was tested in 36 volunteers and 32 patients with symptomatic middle cerebral artery ischemia.
  
  
  RESULTS
  After inhalation of a gas mixture with 5% CO(2) and 95% oxygen the end-expiratory CO(2) content increased by 0.93% +/- 0.31% in the volunteers and 0.89% +/- 0.23% in the patients with symptomatic middle cerebral artery ischemia (P < 0.05). The CVR of the patients with symptomatic middle cerebral artery ischemia could be bigger than 20%. The CVR of middle cerebral artery supply area was correlated with the collateral circulation number and scale, but not with the stenosis degree of M1 segment of middle cerebral artery.
  
  
  CONCLUSIONS
  It is safe and feasible to assess CVR with dynamic computer tomography and gas mixture with 5% CO(2) and 95% oxygen in the patients with symptomatic middle cerebral artery ischemia.
authors: Department of Neurology, Chaoyang Hospital (Jingxi Campus), Beijing 100043, China. liumingyong71@yahoo.com.cn
authors: Ming-Yong
authors: MY
authors: Liu
authors: Li-Chun
authors: LC
authors: Zhou
authors: Yong-Jun
authors: YJ
authors: Wang
authors: Jing
authors: J
authors: Lei
mesh_terms: D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D002245:Carbon Dioxide / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000378:metabolism / Q000503:physiopathology*; D010100:Oxygen / Q000378:metabolism; D012039:Regional Blood Flow; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen