title: Noninvasive quantitation of human liver steatosis using magnetic resonance and bioassay methods.
abstract: The purpose was to evaluate the ability of three magnetic resonance (MR) techniques to detect liver steatosis and to determine which noninvasive technique (MR, bioassays) or combination of techniques is optimal for the quantification of hepatic fat using histopathology as a reference. Twenty patients with histopathologically proven steatosis and 24 control subjects underwent single-voxel proton MR spectroscopy (MRS; 3 voxels), dual-echo in phase/out of phase MR imaging (DEI) and diffusion-weighted MR imaging (DWI) examinations of the liver. Blood or urine bioassays were also performed for steatosis patients. Both MRS and DEI data allowed to detect steatosis with a high sensitivity (0.95 for MRS; 1 for DEI) and specificity (1 for MRS; 0.875 for DEI) but not DWI. Strong correlations were found between fat fraction (FF) measured by MRS, DEI and histopathology segmentation as well as with low density lipoprotein (LDL) and cholesterol concentrations. A Bland-Altman analysis showed a good agreement between the FF measured by MRS and DEI. Partial correlation analyses failed to improve the correlation with segmentation FF when MRS or DEI data were combined with bioassay results. Therefore, FF from MRS or DEI appear to be the best parameters to both detect steatosis and accurately quantify fat liver noninvasively.
authors.affiliation: Département de radiologie, Centre hospitalier de l'Université de Montréal, Montréal, Québec, Canada.
authors.forename: Gaspard
authors.initials: G
authors.lastname: d'Assignies
authors.forename: Martin
authors.initials: M
authors.lastname: Ruel
authors.forename: Abdesslem
authors.initials: A
authors.lastname: Khiat
authors.forename: Luigi
authors.initials: L
authors.lastname: Lepanto
authors.forename: Miguel
authors.initials: M
authors.lastname: Chagnon
authors.forename: Claude
authors.initials: C
authors.lastname: Kauffmann
authors.forename: An
authors.initials: A
authors.lastname: Tang
authors.forename: Louis
authors.initials: L
authors.lastname: Gaboury
authors.forename: Yvan
authors.initials: Y
authors.lastname: Boulanger
mesh_terms: D000328:Adult; D000368:Aged; D001681:Biological Assay / Q000379:methods*; D015415:Biomarkers / Q000032:analysis*; D005234:Fatty Liver / Q000175:diagnosis* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D015415:Biomarkers