title: Evaluation of different cerebral mass lesions by perfusion-weighted MR imaging.
abstract: OBJECTIVE
  To investigate the contribution of perfusion-weighted MR imaging (PWI) by using the relative cerebral blood volume (rCBV) ratio in the differential diagnosis of various intracranial space-occupying lesions.
  
  
  METHODS
  This study involved 105 patients with lesions (high-grade glioma (N=26), low-grade glioma (N=11), meningioma (N=23), metastasis (N=25), hemangioblastoma (N=6), pyogenic abscess (N=4), schwannoma (N=5), and lymphoma (N=5)). The patients were examined with a T2*-weighted (T2*W) gradient-echo single-shot EPI sequence. The rCBV ratios of the lesions were obtained by dividing the values obtained from the normal white matter. Statistical analysis was performed with the Mann-Whitney U-test. A P-value less than 0.05 was considered statistically significant.
  
  
  RESULTS
  The rCBV ratio was 5.76+/-3.35 in high-grade gliomas, 1.69+/-0.51 in low-grade gliomas, 8.02+/-3.89 in meningiomas, 5.27+/-3.22 in metastases, 11.36+/-4.41 in hemangioblastomas, 0.76+/-0.12 in abscesses, 1.10+/-0.32 in lymphomas, and 3.23+/-0.81 in schwannomas. The rCBV ratios were used to discriminate between 1) high- and low-grade gliomas (P<0.001), 2) hemangioblastomas and metastases (P<0.05), 3) abscesses from high-grade gliomas and metastases (P<0.001), 4) schwannomas and meningiomas (P<0.001), 5) lymphomas from high-grade gliomas and metastases (P<0.001), and 6) typical meningiomas and atypical meningiomas (P<0.01).
  
  
  CONCLUSIONS
  rCBV ratios can help discriminate intracranial space-occupying lesions by demonstrating lesion vascularity. It is possible to discriminate between 1) high- and low-grade gliomas, 2) hemangioblastomas and other intracranial posterior fossa masses, 3) abscesses from high-grade gliomas and metastases, 4) schwannomas and meningiomas, 5) lymphomas and high-grade gliomas and metastases, and 6) typical and atypical meningiomas.
authors.affiliation: Department of Radiology, Uludag University Medical School, and Bursa State Hospital, Bursa, Turkey. bhakyemez@uludag.edu.tr
authors.forename: Bahattin
authors.initials: B
authors.lastname: Hakyemez
authors.forename: Cuneyt
authors.initials: C
authors.lastname: Erdogan
authors.forename: Naile
authors.initials: N
authors.lastname: Bolca
authors.forename: Nalan
authors.initials: N
authors.lastname: Yildirim
authors.forename: Gokhan
authors.initials: G
authors.lastname: Gokalp
authors.forename: Mufit
authors.initials: M
authors.lastname: Parlak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001810:Blood Volume; D001932:Brain Neoplasms / Q000175:diagnosis*; D002560:Cerebrovascular Circulation; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric