title: Contrast Leakage Patterns from Dynamic Susceptibility Contrast Perfusion MRI in the Grading of Primary Pediatric Brain Tumors.
abstract: OBJECTIVE
  The pattern of contrast leakage from DSC tissue signal intensity time curves have shown utility in distinguishing adult brain neoplasms, but has limited description in the literature for pediatric brain tumors. The purpose of this study is to evaluate the utility of grading pediatric brain tumors with this technique.
  
  
  METHODS
  A retrospective review of tissue signal-intensity time curves from 63 pediatric brain tumors with preoperative DSC perfusion MR imaging was performed independently by 2 neuroradiologists. Tissue signal-intensity time curves were generated from ROIs placed in the highest perceived tumor relative CBV. The postbolus portion of the curve was independently classified as returning to baseline, continuing above baseline (T1-dominant contrast leakage), or failing to return to baseline (T2*-dominant contrast leakage). Interobserver agreement of curve classification was evaluated by using the Cohen κ. A consensus classification of curve type was obtained in discrepant cases, and the consensus classification was compared with tumor histology and World Health Organization grade.
  
  
  RESULTS
  Tissue signal-intensity time curve classification concordance was 0.69 (95% CI, 0.54-0.84) overall and 0.79 (95% CI, 0.59-0.91) for a T1-dominant contrast leakage pattern. Twenty-five of 25 tumors with consensus T1-dominant contrast leakage were low-grade (positive predictive value, 1.0; 95% CI, 0.83-1.00). By comparison, tumors with consensus T2*-dominant contrast leakage or return to baseline were predominantly high-grade (10/15 and 15/23, respectively) with a high negative predictive value (1.0; 95% CI, 0.83-1.0). For pilomyxoid or pilocytic astrocytomas, a T1-dominant leak demonstrated high sensitivity (0.91; 95% CI, 0.70-0.98) and specificity (0.90, 95% CI, 0.75-0.97).
  
  
  CONCLUSIONS
  There was good interobserver agreement in the classification of DSC perfusion tissue signal-intensity time curves for pediatric brain tumors, particularly for T1-dominant leakage. Among patients with pediatric brain tumors, a T1-dominant leakage pattern is highly specific for a low-grade tumor and demonstrates high sensitivity and specificity for pilocytic or pilomyxoid astrocytomas.
authors.affiliation: From the Department of Radiology, Indiana University School of Medicine, Indianapolis, Indiana. cyho@iupui.edu.
authors.forename: C Y
authors.identifier: http://orcid.org/0000-0002-2358-1851
authors.initials: CY
authors.lastname: Ho
authors.affiliation: From the Department of Radiology, Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: J S
authors.identifier: http://orcid.org/0000-0002-6293-2036
authors.initials: JS
authors.lastname: Cardinal
authors.affiliation: From the Department of Radiology, Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: A P
authors.identifier: http://orcid.org/0000-0003-0898-7623
authors.initials: AP
authors.lastname: Kamer
authors.affiliation: From the Department of Radiology, Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: C
authors.identifier: http://orcid.org/0000-0002-6146-7347
authors.initials: C
authors.lastname: Lin
authors.affiliation: From the Department of Radiology, Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: S F
authors.identifier: http://orcid.org/0000-0001-7213-1761
authors.initials: SF
authors.lastname: Kralik
mesh_terms: D000328:Adult; D001254:Astrocytoma / Q000473:pathology*; D001932:Brain Neoplasms / Q000473:pathology*; D002648:Child; D003287:Contrast Media; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D060787:Neoplasm Grading / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media