title: Simultaneous assessment of cerebral blood volume and diffusion heterogeneity using hybrid IVIM and DK MR imaging: initial experience with brain tumors.
abstract: OBJECTIVE
  To investigate the feasibility of simultaneously assessing cerebral blood volume and diffusion heterogeneity using hybrid diffusion-kurtosis (DK) and intravoxel-incoherent-motion (IVIM) MR imaging.
  
  
  METHODS
  Fifteen healthy volunteers and 30 patients with histologically proven brain tumours (25 WHO grade II-IV gliomas and five metastases) were recruited. On a 3-T system, diffusion-weighted imaging was performed with six b-values ranging from 0 to 1,700 s/mm2. Nonlinear least-squares fitting was employed to extract diffusion coefficient (D), diffusion kurtosis coefficient (K, a measure of the degree of non-Gaussian and heterogeneous diffusion) and intravascular volume fraction (f, a measure proportional to cerebral blood volume). Repeated-measures multivariate analysis of variance and receiver operating characteristic analysis were performed to assess the ability of D/K/f in differentiating contrast-enhanced tumour from peritumoral oedema and normal-appearing white matter.
  
  
  RESULTS
  Based on our imaging setting (baseline signal-to-noise ratio = 32-128), coefficient of variation was 14-20 % for K, ~6 % for D and 26-44 % for f. The indexes were able to differentiate contrast-enhanced tumour (Wilks' λ = 0.026, p < 10-3), and performance was greatest with K, followed by f and D.
  
  
  CONCLUSIONS
  Hybrid DK IVIM imaging is capable of simultaneously measuring cerebral perfusion and diffusion indexes that together may improve brain tumour diagnosis.
  
  
  CONCLUSIONS
  • Hybrid DK-IVIM imaging allows simultaneous measurement of K, D and f. • Combined K/D/f better demarcates contrast-enhanced tumour than they do separately. • f correlates better with contrast-leakage-corrected CBVDSCthan with uncorrected CBVDSC.
authors.affiliation: Graduate Institute of Oncology, National Taiwan University, No. 1, Sec. 1, Ren-Ai Road, Taipei, 100, Taiwan. wenchau@ntu.edu.tw.|Graduate Institute of Clinical Medicine, National Taiwan University, Taipei, Taiwan. wenchau@ntu.edu.tw.|Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan. wenchau@ntu.edu.tw.|Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan. wenchau@ntu.edu.tw.
authors.forename: Wen-Chau
authors.initials: WC
authors.lastname: Wu
authors.affiliation: Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Shun-Chung
authors.initials: SC
authors.lastname: Yang
authors.affiliation: Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ya-Fang
authors.initials: YF
authors.lastname: Chen
authors.affiliation: Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Han-Min
authors.initials: HM
authors.lastname: Tseng
authors.affiliation: Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Pei-Chi
authors.initials: PC
authors.lastname: My
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D000071937:Cerebral Blood Volume / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D005910:Glioma / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009038:Motion; D064847:Multimodal Imaging; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D055815:Young Adult
keywords: Brain tumour; Cerebral blood volume; Diffusion; Diffusion imaging; Magnetic resonance imaging