title: Differentiation of glioblastoma multiforme and single brain metastasis by peak height and percentage of signal intensity recovery derived from dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging.
abstract: OBJECTIVE
  Glioblastoma multiforme (GBM) and single brain metastasis (MET) are the 2 most common malignant brain tumors that can appear similar on anatomic imaging but require vastly different treatment strategy. The purpose of our study was to determine whether the peak height and the percentage of signal intensity recovery derived from dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion MR imaging could differentiate GBM and MET.
  
  
  METHODS
  Forty-three patients with histopathologic diagnosis of GBM (n=27) or MET (n=16) underwent DSC perfusion MR imaging in addition to anatomic MR imaging before surgery. Regions of interest were drawn around the nonenhancing peritumoral T2 lesion (PTL) and the contrast-enhancing lesion (CEL). T2* signal intensity-time curves acquired during the first pass of gadolinium contrast material were converted to the changes in relaxation rate to yield T2* relaxivity (Delta R2*) curve. The peak height of maximal signal intensity drop and the percentage of signal intensity recovery at the end of first pass were measured for each voxel in the PTL and CEL regions of the tumor.
  
  
  RESULTS
  The average peak height for the PTL was significantly higher (P=.04) in GBM than in MET. The average percentage of signal intensity recovery was significantly reduced in PTL (78.4% versus 82.8%; P=.02) and in CEL (62.5% versus 80.9%, P<.01) regions of MET compared with those regions in the GBM group.
  
  
  CONCLUSIONS
  The findings of our study show that the peak height and the percentage of signal intensity recovery derived from the Delta R2* curve of DSC perfusion MR imaging can differentiate GBM and MET.
authors.affiliation: Department of Radiology, University of California, San Francisco Medical Center, San Francisco, CA 94143-0628, USA. soonmee.cha@radiology.ucsf.edu
authors.forename: S
authors.initials: S
authors.lastname: Cha
authors.forename: J M
authors.initials: JM
authors.lastname: Lupo
authors.forename: M-H
authors.initials: MH
authors.lastname: Chen
authors.forename: K R
authors.initials: KR
authors.lastname: Lamborn
authors.forename: M W
authors.initials: MW
authors.lastname: McDermott
authors.forename: M S
authors.initials: MS
authors.lastname: Berger
authors.forename: S J
authors.initials: SJ
authors.lastname: Nelson
authors.forename: W P
authors.initials: WP
authors.lastname: Dillon
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D002277:Carcinoma / Q000175:diagnosis* / Q000556:secondary*; D003937:Diagnosis, Differential; D005260:Female; D005909:Glioblastoma / Q000175:diagnosis*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010477:Perfusion / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity