title: Perfusion-sensitive MR imaging of gliomas: comparison between gradient-echo and spin-echo echo-planar imaging techniques.
abstract: OBJECTIVE
  The different sensitivities to vessel size of gradient-echo echo-planar imaging (GE-EPI) and spin-echo EPI (SE-EPI) might indicate the relative cerebral blood volumes (rCBVs) of different tumor sizes. The techniques of GE-EPI and SE-EPI were compared for detecting low- versus high-grade gliomas.
  
  
  METHODS
  Six patients with low-grade gliomas and 19 patients with high-grade gliomas underwent two perfusion-sensitive MR procedures, one produced by a GE- and the other by an SE-EPI technique. Maximum rCBV ratios normalized with rCBV of contralateral white matter were calculated for evaluation. P <.05 was considered statistically significant.
  
  
  RESULTS
  Maximum rCBV ratios of high-grade gliomas obtained with the GE-EPI technique (mean, 5.0 +/- 2.9) were significantly higher than those obtained with the SE-EPI technique (mean, 2.9 +/- 2.3) (P =.02). Maximum rCBV ratios of low-grade gliomas obtained with the GE-EPI technique (mean, 1.2 +/- 0.7) were almost equal to those obtained with the SE-EPI technique (mean, 1.2 +/- 0.6), and there was no significant difference (P =.66). The difference in the maximum rCBV ratios between the low- and high-grade gliomas reached significance when obtained with the GE-EPI technique (P =.01).
  
  
  CONCLUSIONS
  The GE-EPI technique seems more useful for detecting low- versus high-grade gliomas than the SE-EPI technique.
authors.affiliation: Department of Radiology, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sugahara
authors.forename: Y
authors.initials: Y
authors.lastname: Korogi
authors.forename: M
authors.initials: M
authors.lastname: Kochi
authors.forename: Y
authors.initials: Y
authors.lastname: Ushio
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001810:Blood Volume / Q000502:physiology*; D001921:Brain / Q000098:blood supply / Q000473:pathology; D001932:Brain Neoplasms / Q000098:blood supply* / Q000175:diagnosis; D020295:Brain Stem Neoplasms / Q000098:blood supply / Q000175:diagnosis; D017352:Echo-Planar Imaging; D005260:Female; D005910:Glioma / Q000098:blood supply* / Q000175:diagnosis; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011149:Pons / Q000098:blood supply / Q000473:pathology; D011446:Prospective Studies; D012039:Regional Blood Flow / Q000502:physiology; D012680:Sensitivity and Specificity