title: Assessment of diagnostic accuracy of perfusion MR imaging in primary and metastatic solitary malignant brain tumors.
abstract: OBJECTIVE
  The purpose of this study was to estimate the diagnostic accuracy of relative cerebral blood volume (rCBV) measurement in preoperative grading and differentiation of solitary intra-axial malignant brain tumors.
  
  
  METHODS
  Thirty-six low-grade glial tumors (LGGTs), 22 high-grade glial tumors (HGGTs), and 17 metastases (METs) were prospectively evaluated by MR imaging and standard dynamic susceptibility contrast-enhanced gradient echo, echoplanar imaging during first pass of a bolus injection of contrast material. Normalized rCBV values from tumoral (rCBV(T)) and peritumoral (rCBV(P)) areas were calculated by standard software and statistically tested independently.
  
  
  RESULTS
  The mean differences of rCBV(T) and rCBV(P) values between LGGT (2.30 +/- 1.12 and 1.18 +/- 0.24) and HGGT (5.42 +/- 1.52 and 2.17 +/- 0.82) (P < .001); HGGTs and METs (3.21 +/- 0.98 and 0.97 +/- 0.09) (P < .001); and LGGTs and METs (P < .05 and P < .001, respectively) were significant. No clear cutoff value was present. A clear rCBV(T) cutoff value of 2.6 was detected for differentiation of low- (1.75 +/- 0.38; LGA) versus high-grade (4.78 +/- 0.99; HGA) astrocytomas when nonastrocytic glial tumors were excluded. The rCBV(T) values were linearly correlated with degree of malignancy (r = 0.869; P < .001). Cutoff rCBV(P) values of 1.1 and 1.2 were quite effective in differentiation of METs from LGGTs and HGGTs, respectively. The overall efficacy of rCBV was higher in grading than in differentiation.
  
  
  CONCLUSIONS
  The diagnostic accuracy of rCBV measurement is higher in grading of glial brain tumors than in differentiation of HGGTs from solitary intra-axial METs. The astrocytic and nonastrocytic glial tumors have to be evaluated separately for precise grading.
authors.affiliation: Department of Radiology, Gulhane Military Medical School, Ankara, Turkey.
authors.forename: Nail
authors.initials: N
authors.lastname: Bulakbasi
authors.forename: Murat
authors.initials: M
authors.lastname: Kocaoglu
authors.forename: Anar
authors.initials: A
authors.lastname: Farzaliyev
authors.forename: Cem
authors.initials: C
authors.lastname: Tayfun
authors.forename: Taner
authors.initials: T
authors.lastname: Ucoz
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Somuncu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001810:Blood Volume; D001932:Brain Neoplasms / Q000098:blood supply* / Q000473:pathology / Q000556:secondary; D002560:Cerebrovascular Circulation; D002648:Child; D003287:Contrast Media; D017352:Echo-Planar Imaging; D005910:Glioma / Q000098:blood supply / Q000473:pathology; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged
chemical_list: D003287:Contrast Media