title: Automated Processing of Dynamic Contrast-Enhanced MRI: Correlation of Advanced Pharmacokinetic Metrics with Tumor Grade in Pediatric Brain Tumors.
abstract: Pharmacokinetic parameters from dynamic contrast-enhanced MR imaging have proved useful for differentiating brain tumor grades in adults. In this study, we retrospectively reviewed dynamic contrast-enhanced perfusion data from children with newly diagnosed brain tumors and analyzed the pharmacokinetic parameters correlating with tumor grade.
  
  
  
  Dynamic contrast-enhanced MR imaging data from 38 patients were analyzed by using commercially available software. Subjects were categorized into 2 groups based on pathologic analyses consisting of low-grade (World Health Organization I and II) and high-grade (World Health Organization III and IV) tumors. Pharmacokinetic parameters were compared between the 2 groups by using linear regression models. For parameters that were statistically distinct between the 2 groups, sensitivity and specificity were also estimated.
  
  
  
  Eighteen tumors were classified as low-grade, and 20, as high-grade. Transfer constant from the blood plasma into the extracellular extravascular space (Ktrans), rate constant from extracellular extravascular space back into blood plasma (Kep), and extracellular extravascular volume fraction (Ve) were all significantly correlated with tumor grade; high-grade tumors showed higher Ktrans, higher Kep, and lower Ve. Although all 3 parameters had high specificity (range, 82%-100%), Kephad the highest specificity for both grades. Optimal sensitivity was achieved for Ve, with a combined sensitivity of 76% (compared with 71% for Ktransand Kep).
  
  
  
  Pharmacokinetic parameters derived from dynamic contrast-enhanced MR imaging can effectively discriminate low- and high-grade pediatric brain tumors.
authors.affiliation: From the Departments of Radiology (S.V., C.S., T.Y.P.) sridhar.vajapeyam@childrens.harvard.edu.|Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts.
authors.forename: S
authors.identifier: 0000-0002-1782-1919
authors.initials: S
authors.lastname: Vajapeyam
authors.affiliation: From the Departments of Radiology (S.V., C.S., T.Y.P.).|Neurology (C.S.), Boston Children's Hospital, Boston, Massachusetts.|Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts.
authors.forename: C
authors.identifier: 0000-0001-9814-1802
authors.initials: C
authors.lastname: Stamoulis
authors.affiliation: Cancer Center (K.R.), Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: K
authors.identifier: 0000-0002-7662-1220
authors.initials: K
authors.lastname: Ricci
authors.affiliation: Department of Pediatric Oncology (M.K.), Dana-Farber Cancer Center, Boston, Massachusetts.|Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts.
authors.forename: M
authors.identifier: 0000-0003-2184-7692
authors.initials: M
authors.lastname: Kieran
authors.affiliation: From the Departments of Radiology (S.V., C.S., T.Y.P.).|Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts.
authors.forename: T Young
authors.identifier: 0000-0002-0814-0791
authors.initials: TY
authors.lastname: Poussaint
mesh_terms: D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D002648:Child; D003287:Contrast Media / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008962:Models, Theoretical; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media