title: Comparison of the Diagnostic Accuracy of DSC- and Dynamic Contrast-Enhanced MRI in the Preoperative Grading of Astrocytomas.
abstract: OBJECTIVE
  Dynamic contrast-enhanced MR imaging parameters can be biased by poor measurement of the vascular input function. We have compared the diagnostic accuracy of dynamic contrast-enhanced MR imaging by using a phase-derived vascular input function and "bookend" T1 measurements with DSC MR imaging for preoperative grading of astrocytomas.
  
  
  METHODS
  This prospective study included 48 patients with a new pathologic diagnosis of an astrocytoma. Preoperative MR imaging was performed at 3T, which included 2 injections of 5-mL gadobutrol for dynamic contrast-enhanced and DSC MR imaging. During dynamic contrast-enhanced MR imaging, both magnitude and phase images were acquired to estimate plasma volume obtained from phase-derived vascular input function (Vp_Φ) and volume transfer constant obtained from phase-derived vascular input function (K(trans)_Φ) as well as plasma volume obtained from magnitude-derived vascular input function (Vp_SI) and volume transfer constant obtained from magnitude-derived vascular input function (K(trans)_SI). From DSC MR imaging, corrected relative CBV was computed. Four ROIs were placed over the solid part of the tumor, and the highest value among the ROIs was recorded. A Mann-Whitney U test was used to test for difference between grades. Diagnostic accuracy was assessed by using receiver operating characteristic analysis.
  
  
  RESULTS
  Vp_ Φ and K(trans)_Φ values were lower for grade II compared with grade III astrocytomas (P < .05). Vp_SI and K(trans)_SI were not significantly different between grade II and grade III astrocytomas (P = .08-0.15). Relative CBV and dynamic contrast-enhanced MR imaging parameters except for K(trans)_SI were lower for grade III compared with grade IV (P ≤ .05). In differentiating low- and high-grade astrocytomas, we found no statistically significant difference in diagnostic accuracy between relative CBV and dynamic contrast-enhanced MR imaging parameters.
  
  
  CONCLUSIONS
  In the preoperative grading of astrocytomas, the diagnostic accuracy of dynamic contrast-enhanced MR imaging parameters is similar to that of relative CBV.
authors.affiliation: From the Departments of Radiology (T.B.N., G.O.C., C.H.T., R.E.T., I.G.C., S.C.) thnguyen@toh.on.ca.
authors.forename: T B
authors.initials: TB
authors.lastname: Nguyen
authors.affiliation: From the Departments of Radiology (T.B.N., G.O.C., C.H.T., R.E.T., I.G.C., S.C.).
authors.forename: G O
authors.initials: GO
authors.lastname: Cron
authors.affiliation: Internal Medicine (K.P.).
authors.forename: K
authors.initials: K
authors.lastname: Perdrizet
authors.affiliation: Faculty of Medicine (K.B.), Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Bezzina
authors.affiliation: From the Departments of Radiology (T.B.N., G.O.C., C.H.T., R.E.T., I.G.C., S.C.).
authors.forename: C H
authors.initials: CH
authors.lastname: Torres
authors.affiliation: From the Departments of Radiology (T.B.N., G.O.C., C.H.T., R.E.T., I.G.C., S.C.).
authors.forename: S
authors.initials: S
authors.lastname: Chakraborty
authors.affiliation: Pathology (G.H.J., J.W.).
authors.forename: J
authors.initials: J
authors.lastname: Woulfe
authors.affiliation: Pathology (G.H.J., J.W.).
authors.forename: G H
authors.initials: GH
authors.lastname: Jansen
authors.affiliation: Surgery, Division of Neurosurgery (J.S.).
authors.forename: J
authors.initials: J
authors.lastname: Sinclair
authors.affiliation: From the Departments of Radiology (T.B.N., G.O.C., C.H.T., R.E.T., I.G.C., S.C.).
authors.forename: R E
authors.initials: RE
authors.lastname: Thornhill
authors.affiliation: Medical Physics (C.F., I.G.C.).
authors.forename: C
authors.initials: C
authors.lastname: Foottit
authors.affiliation: Department of Medical Biophysics (B.Z.), University of Toronto, Toronto, Ontario, Canada.
authors.forename: B
authors.initials: B
authors.lastname: Zanette
authors.affiliation: From the Departments of Radiology (T.B.N., G.O.C., C.H.T., R.E.T., I.G.C., S.C.) Medical Physics (C.F., I.G.C.).
authors.forename: I G
authors.identifier: http://orcid.org/0000-0002-0464-8790
authors.initials: IG
authors.lastname: Cameron
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001254:Astrocytoma / Q000473:pathology*; D001932:Brain Neoplasms / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading / Q000379:methods*; D009942:Organometallic Compounds; D011300:Preoperative Care / Q000379:methods*; D011446:Prospective Studies; D012372:ROC Curve; D018709:Statistics, Nonparametric
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol