Measurements of Diffusion and Perfusion in Vertebral Bone Marrow Using Intravoxel Incoherent Motion (IVIM) With Multishot, Readout-Segmented (RESOLVE) Echo-Planar Imaging

BackgroundA limited number of studies have used the intravoxel incoherent motion (IVIM) approach on bone marrow. In none of the previous studies were the effects of fat suppression on the IVIM parameters investigated. PurposeTo measure the water diffusion coefficient and the perfusion fraction in vertebral bone marrow using IVIM with multishot, readout-segmented (RESOLVE) echo-planar imaging and to assess the effects of different fat suppression techniques on the measurement of the IVIM parameters. Study TypeProspective. Population/SubjectsSix healthy volunteers (24.24.3 years). Field Strength/Sequence1.5T, RESOLVE. AssessmentFour experiments were performed: 1) RESOLVE imaging without fat suppression, 2) with fat saturation (FS), 3) with spectral attenuated inversion recovery (SPAIR), and 4) with short-tau inversion recovery (STIR). The water diffusion coefficient D, pseudo-diffusion coefficient D*, and the perfusion fraction f were assessed in the vertebral bodies of the lumbar vertebrae. Statistical TestsOne-way repeated-measures analysis of variance (ANOVA) followed by Bonferroni's multiple comparison test. ResultsThe RESOLVE IVIM protocol allowed for measurement of D, D*, and f in all volunteers. The signal of lipid protons affected the quantification of the IVIM diffusion coefficient: D=0.240.10 (x10(-3) mm(2)/s), no FS; D=0.430.07 (x10(-3) mm(2)/s), FS; D=0.420.07 (x10(-3) mm(2)/s), SPAIR; D=0.35 +/- 0.10 (x10(-3) mm(2)/s), STIR; and IVIM perfusion fraction f=7.5 +/- 1.9% no FS, f=14.5 +/- 5.4%, FS; f=12.5 +/- 2.6%, SPAIR; f=18.1 +/- 6.1%, STIR. No significant effect (P=0.36) was found on the quantification of D*. Data ConclusionAn IVIM-MRI protocol using the RESOLVE sequence was implemented for measurements of vertebral bone marrow diffusion and the perfusion. The comparison between the protocols with and without fat suppression indicates that the lipid signal results in an underestimation of both D and f.Level of Evidence: Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;49:768-776.