title: Non-parametric intravoxel incoherent motion analysis in patients with intracranial lesions: Test-retest reliability and correlation with arterial spin labeling.
abstract: Intravoxel incoherent motion (IVIM) analysis of diffusion imaging data provides biomarkers of true passive water diffusion and perfusion properties. A new IVIM algorithm with variable adjustment of the b-value threshold separating diffusion and perfusion effects was applied for cerebral tissue characterization in healthy volunteers, computation of test-retest reliability, correlation with arterial spin labeling, and assessment of applicability in a small cohort of patients with malignant intracranial masses. The main results of this study are threefold: (i) accounting for regional differences in the separation of the perfusion and the diffusion components improves the reliability of the model parameters; (ii) if differences in the b-value threshold are not accounted for, a significant tissue-dependent systematic bias of the IVIM parameters occurs; (iii) accounting for voxel-wise differences in the b-value threshold improves the correlation with CBF measurements in healthy volunteers and patients. The proposed algorithm provides a robust characterization of regional micro-vascularization and cellularity without a priori assumptions on tissue diffusion properties. The glioblastoma multiforme with its inherently high variability of tumor vascularization and tumor cell density may benefit from a non-invasive clinical characterization of diffusion and perfusion properties.
authors.affiliation: Department of Radiation Oncology, University Hospital Zurich and University of Zurich, Switzerland; Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland.
authors.forename: Sonja
authors.initials: S
authors.lastname: Stieb
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich and University of Zurich, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Boss
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich and University of Zurich, Switzerland.
authors.forename: Moritz C
authors.initials: MC
authors.lastname: Wurnig
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich and University of Zurich, Switzerland; Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Switzerland.
authors.forename: Pinar S
authors.initials: PS
authors.lastname: Özbay
authors.affiliation: Department of Neurology, University Hospital Zurich and University of Zurich, Switzerland.
authors.forename: Tobias
authors.initials: T
authors.lastname: Weiss
authors.affiliation: Department of Radiation Oncology, University Hospital Zurich and University of Zurich, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Guckenberger
authors.affiliation: Department of Radiation Oncology, University Hospital Zurich and University of Zurich, Switzerland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Riesterer
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich and University of Zurich, Switzerland. Electronic address: cristina.rossi@usz.ch.
authors.forename: Cristina
authors.initials: C
authors.lastname: Rossi
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001930:Brain Injuries / Q000000981:diagnostic imaging*; D002555:Cerebrospinal Fluid / Q000502:physiology*; D015331:Cohort Studies; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009038:Motion; D055420:Perfusion Imaging; D013113:Spin Labels; D018709:Statistics, Nonparametric; D055815:Young Adult
chemical_list: D013113:Spin Labels
keywords: ASL; Arterial spin labeling; Glioblastoma multiforme; IVIM; Intravoxel incoherent motion; Test-retest reliability