title: Multislice continuous arterial spin-labeled perfusion MRI in patients with chronic occlusive cerebrovascular disease: a correlative study with CO2 PET validation.
abstract: OBJECTIVE
  To compare the use of multislice continuous arterial spin labeling (CASL) and CO(2) positron emission tomography (PET) to assess CBF in patients with chronic occlusive cerebrovascular disease for the validation of quantitative CASL perfusion in an altered hemodynamic state.
  
  
  METHODS
  Eleven patients with occlusive carotid artery disease were studied with CASL and conventional MRI. Cerebral blood flow (CBF) was also measured with O(15)-labeled CO(2) gas using a whole-body PET scanner. The average values within region of interests (ROIs) drawn on coregistered CASL and PET images were used for the linear regression analysis and to assess the effect of transit time on the quantification using CASL.
  
  
  RESULTS
  In all patients there was a significant correlation between the CBF values from CASL and PET (r = 0.71 +/- 0.07, P < 0.001). The slope of regression lines varied widely among patients (0.54-1.77). Longer transit times were estimated in four of 11 patients in the hypoperfusion region.
  
  
  CONCLUSIONS
  Quantification of CBF using CASL is feasible and reasonable, even when employed in a routine clinical setting. However, the long transit time may lead to underestimation of the affected side in occlusive cerebrovascular disease.
authors: Department of Radiology, Faculty of Medical Science, University of Fukui, 23 Shimoaizuki, Yoshida-gun, Katsukoa-cho, Fukui 910-1193, Japan. kimura@fmsrsa.fukui-med.ac.jp
authors: Hirohiko
authors: H
authors: Kimura
authors: Hirotsugu
authors: H
authors: Kado
authors: Yoshio
authors: Y
authors: Koshimoto
authors: Tatsurou
authors: T
authors: Tsuchida
authors: Yoshiharu
authors: Y
authors: Yonekura
authors: Harumi
authors: H
authors: Itoh
mesh_terms: D000368:Aged; D001784:Blood Gas Analysis; D002545:Brain Ischemia / Q000175:diagnosis*; D016893:Carotid Stenosis / Q000175:diagnosis*; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000175:diagnosis*; D015331:Cohort Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014655:Vascular Resistance