title: Robust estimation of the cerebral blood flow in arterial spin labelling.
abstract: The introduction of arterial spin labelling (ASL) techniques in magnetic resonance imaging (MRI) has made feasible a non-invasive measurement of the cerebral blood flow (CBF). However, to date, the low signal-to-noise ratio of ASL gives us no option but to repeat the acquisition to accumulate enough data in order to get a reliable signal. The perfusion signal is then usually extracted by averaging across the repetitions. But the sample mean is very sensitive to outliers. A single incorrect observation can therefore be the source of strong detrimental effects on the perfusion-weighted image estimated with the sample mean. We propose to estimate robust ASL CBF maps with M-estimators to overcome the deleterious effects of outliers. The behavior of this method is compared to z-score thresholding as recommended in Tan et al. (Journal of Magnetic Resonance Imaging 2009;29(5):1134-9.). Validation on simulated and real data is provided. Quantitative validation is undertaken by measuring the correlation with the most widespread technique to measure perfusion with MRI: dynamic susceptibility weighted contrast imaging.
authors.affiliation: University of Rennes 1, Faculty of medecine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; Inria, VISAGES project-team, F-35042 Rennes, France. Electronic address: contact@camillemaumet.com.
authors.forename: Camille
authors.initials: C
authors.lastname: Maumet
authors.affiliation: University of Rennes 1, Faculty of medecine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; Inria, VISAGES project-team, F-35042 Rennes, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Maurel
authors.affiliation: University of Rennes 1, Faculty of medecine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; Inria, VISAGES project-team, F-35042 Rennes, France; CHU Rennes, Department of Neuroradiology, F-35033 Rennes, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Ferré
authors.affiliation: University of Rennes 1, Faculty of medecine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; Inria, VISAGES project-team, F-35042 Rennes, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Barillot
mesh_terms: D001783:Blood Flow Velocity; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000503:physiopathology*; D002536:Cerebral Arteries / Q000473:pathology / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009389:Neovascularization, Pathologic / Q000175:diagnosis* / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013113:Spin Labels
chemical_list: D013113:Spin Labels
keywords: Arterial spin labelling; M-estimators; Robust statistics