title: Solitary metastases and high-grade gliomas: radiological differentiation by morphometric analysis and perfusion-weighted MRI.
abstract: OBJECTIVE
  To evaluate the value of morphometric analysis and perfusion-weighted magnetic resonance imaging (MRI) in differentiating solitary metastases from high-grade gliomas.
  
  
  METHODS
  Forty-eight tumours (22 high-grade gliomas and 26 solitary hemispheric metastases) were evaluated using conventional and perfusion-weighted MRI. T2-weighted, gradient-echo, echo-planar sequences were used for perfusion-weighted MRI. Relative cerebral blood volume (rCBV) ratios were calculated by dividing the rCBV of the intratumoural and peritumoural areas with the average CBV value of the normal white matter areas. Morphometric analysis was carried out by proportioning the area of peritumoural oedema to the mass area. Mann-Whitney U test and ROC curve analysis were applied for statistical analysis. P<0.05 was accepted as statistically significant.
  
  
  RESULTS
  Mean rCBV ratios of intratumoural areas of high-grade gliomas and metastases were 5.02+/-2.47 and 4.62+/-2.46, respectively. No statistically significant difference was found (p=0.515). rCBV ratios of peritumoural oedema were 0.89+/-0.51 in high-grade gliomas and 0.31+/-0.12 in metastases. The difference was statistically significant (p<0.001). According to the results of morphometric analysis, a statistically significant difference was present between the two tumour types (p<0.001).
  
  
  CONCLUSIONS
  Measuring the oedema: mass and rCBV ratios of the oedema surrounding the tumour prior to operation in solitary masses proved to be useful for differentiating metastases from high-grade gliomas.
authors.affiliation: Department of Radiology, Division of Neuroradiology, Uludag University School of Medicine, Bursa, Turkey. bahattinh@hotmail.com
authors.forename: B
authors.initials: B
authors.lastname: Hakyemez
authors.forename: C
authors.initials: C
authors.lastname: Erdogan
authors.forename: G
authors.initials: G
authors.lastname: Gokalp
authors.forename: A
authors.initials: A
authors.lastname: Dusak
authors.forename: M
authors.initials: M
authors.lastname: Parlak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001929:Brain Edema / Q000175:diagnosis; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000556:secondary*; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000556:secondary; D002560:Cerebrovascular Circulation; D003937:Diagnosis, Differential; D005260:Female; D005909:Glioblastoma / Q000175:diagnosis; D005910:Glioma / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult