title: Diffusion tensor and dynamic susceptibility contrast MRI in glioblastoma.
abstract: OBJECTIVE
  We prospectively investigated the correlation between diffusion tensor (DTI), dynamic susceptibility contrast (DSC) perfusion MRI metrics and Ki-67 labelling index in glioblastomas.
  
  
  METHODS
  We studied seventeen patients who were operated on for glioblastoma. DTI and DSC MRI were performed within a week prior to surgical excision. Lesion/normal ratios were calculated for the apparent diffusion coefficient (ADC), fractional anisotropy (FA), relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time (rMTT) ratio. In the excised tumour specimens Ki-67 antigen expression was evaluated by the MIB-1 immunostaining method.
  
  
  RESULTS
  A significant correlation was observed between Ki-67 index and ADC ratio (r = -0.528, p = 0.029) and FA ratio (r = 0.589, p = 0.012). rCBV and rMTT presented a trend towards significant correlation with Ki-67 index (r = 0.628, p = 0.07 and r = 0.644, p = 0.06 respectively). There was a trend towards better survival for patients with gross total tumour excision and FA values lower than 0.48 (p = 0.1 and p = 0.09 respectively). No significant correlation was found between ADC ratio, rCBV, rCBF, rMTT and overall survival.
  
  
  CONCLUSIONS
  ADC ratio, FA ratio, rCBV and rMTT tumour/normal tissue ratios may represent indicators of glioma proliferation. FA values may hold promise for predicting survival in patients with glioblastoma.
authors.affiliation: Department of Radiology, University Hospital of Ioannina, Ioannina, Greece.
authors.forename: Anastasia K
authors.initials: AK
authors.lastname: Zikou
authors.forename: George A
authors.initials: GA
authors.lastname: Alexiou
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Kosta
authors.forename: Ann
authors.initials: A
authors.lastname: Goussia
authors.forename: Loukas
authors.initials: L
authors.lastname: Astrakas
authors.forename: Periklis
authors.initials: P
authors.lastname: Tsekeris
authors.forename: Spyridon
authors.initials: S
authors.lastname: Voulgaris
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Malamou-Mitsi
authors.forename: Athanasios P
authors.initials: AP
authors.lastname: Kyritsis
authors.forename: Maria I
authors.initials: MI
authors.lastname: Argyropoulou
mesh_terms: D000368:Aged; D001932:Brain Neoplasms / Q000473:pathology* / Q000601:surgery; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D005909:Glioblastoma / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D019394:Ki-67 Antigen; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D016019:Survival Analysis
chemical_list: D019394:Ki-67 Antigen