title: Hemodynamic studies on brain CT perfusion imaging with varied injection rates.
abstract: OBJECTIVE
  This study aimed to determine a contrast medium injection rate that ensures both accuracy for data and safety for operation by comparing hemodynamic parameters of brain CT perfusion imaging with varied injection rates.
  
  
  METHODS
  Twenty-four healthy volunteers were divided into three groups based on contrast medium injection rates (4.5, 6.0, and 7.5 ml/s). For all subjects, CT perfusion scanning was started at 4 s after antecubital venous bolus of contrast media injection. A perfusion-analyzing software package was used to produce a time-density curve in the anterior cerebral artery and the superior sagittal sinus and calculate the regional cerebral blood flow (rCBF) in the gray matter and the white matter. The hemodynamic indices were compared among the three groups, and statistical analysis was carried out using the F test.
  
  
  RESULTS
  The time for the arterial rise to reach the peak value for the 7.5-ml/s group was only 0.2 s ahead of the initiation time for the rise of the superior sagittal sinus. The differences of rCBF in the gray matter and the white matter among the three groups were statistically significant. rCBF in the gray matter and the white matter for the 7.5-ml/s group was 52.8 ml x min(-1) 100 g(-1) . (+/-3.1) and 21.9 ml x min(-1) . 100 g(-1) (+/-2.4), respectively.
  
  
  CONCLUSIONS
  The use of the 7.5-ml/s injection rate can meet the prerequisite of the maximum slope model, and the resulting rCBF can be very close to that measured by positron emission tomography. Therefore, 7.5 ml/s was an ideal contrast medium injection rate.
authors: Imaging Center, the First Affiliated Hospital of Soochow University, Suzhou City, Jiangsu Province 215006, China. hch5305@163.com
authors: Chun-Hong
authors: CH
authors: Hu
authors: Qing-De
authors: QD
authors: Wu
authors: Xiao-Yun
authors: XY
authors: Hu
authors: Xiang-Ming
authors: XM
authors: Fang
authors: Tong-Hua
authors: TH
authors: Zhang
authors: Yi
authors: Y
authors: Ding
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging* / Q000502:physiology*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media