title: Correlation of volume transfer coefficient Ktrans with histopathologic grades of gliomas.
abstract: OBJECTIVE
  To evaluate the roles of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and optimum tracer kinetic parameters in the noninvasive grading of the glial brain tumors with histopathological grades (I-IV).
  
  
  METHODS
  Twenty-eight patients with histopathologically graded gliomas were imaged. Images with five flip angles were acquired before injection of gadolinium-DTPA and were processed to calculate the T(1) value of each region of interest (ROI). All the DCE-MRI data acquired during the injection were processed based on the MRI signal and pharmacokinetic models to establish concentration-time curves in the ROIs drawn within the tumors, contralateral normal areas, and area of the individual artery input functions (iAIF) of each patient. A nonlinear least-square-fitting method was used to obtain tracer kinetic parameters. Kruskal-Wallis H-test and Mann-Whitney U-test were applied to these parameters in different histopathological grade groups for statistical differences (P < 0.05).
  
  
  RESULTS
  Volume transfer coefficient (K(trans) ) and extravascular extracellular space volume fraction (V(e) ) calculated using iAIFs can be used not only to distinguish the low (ie, I and II) from the high (ie, III and IV) grade gliomas (P( Ktrans) < 0.001 and P(Ve) < 0.001), but also grade II from III (P( Ktrans) = 0.016 and P(Ve) = 0.033).
  
  
  CONCLUSIONS
  K(trans) is the most sensitive and specific parameter in noninvasive grading, distinguishing the high (III and IV) from the low (I and II) grade and high grade III from low grade II gliomas.
authors.affiliation: Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Key laboratory for MRI, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.forename: Lijuan
authors.initials: L
authors.lastname: Zhang
authors.forename: Bensheng
authors.initials: B
authors.lastname: Qiu
authors.forename: Li
authors.initials: L
authors.lastname: Meng
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Wang
authors.forename: Bob L
authors.initials: BL
authors.lastname: Hou
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology*; D003287:Contrast Media / Q000493:pharmacokinetics; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D005910:Glioma / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D055815:Young Adult
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA