Quantitative chemical shift-encoded MRI is an accurate method to quantify marrow fat / 实用放射学杂志

ABSTRACT

Objective To validate a chemical shift-encoded MRI(CSE-MRI)water-fat imaging for quantifying vertebral marrow fat content using MRS as the reference standard.Methods MRS and CSE-MRI were performed to calculate proton density fat fraction(PDFF) in 83 subjects,including 41 normal bone mass,26 osteopenia and 16 osteoporosis.Eight participants were scanned three times with repositioning to assess the repeatability of CSE-MRI PDFF measurements.Agreements of intra-observer and inter-observer were evaluated by intraclass correlation coefficient(ICC).Linear regression,Bland-Altman 95% limit of agreement and Lin's concordance correlation coefficient were calculated.Results The repeatability for CSE-MRI PDFF measurements expressed as absolute precision error was 1.45%.PDFF was 62.1%±11.1% by MRS and 60.4%±10.1% by CSE-MRI in 83 subjects.There were significant differences in PDFF among the normal bone mass,osteopenia and osteoporosis groups after adjusting for age,years since menopause and body mass index (all P<0.001).The intra-and inter-rater reliability for duplicate measurements at CSE-MRI PDFF were more than 0.993.Pearson correlation coefficient was 0.979 and Lin's concordance correlation coefficient was 0.962.All data points calculated using the Bland-Altman method were within the limits of agreement.Inverse associations were observed between BMD (r=-0.560--0.710)and CSE-MRI-based PDFF,and between BMD (r=-0.539--0.706)and MRS-based PDFF in various groups.Conclusion CSE-MRI with multiple lipids peak model and T2?-correction is equally accurate in characterizing marrow fat content as MRS.