Patent ID: 10151814

Abstract:
A method for improving image homogeneity of image data acquired from balanced Steady-State Free Precision (bSSFP) sequences in magnetic resonance imaging. Multiple bSSFP sequences are performed with different radio frequency phase increments to create multiple bSSFP image volumes with different phase offsets ϕ. Each image has voxels whose intensity M is a function of a nuclear resonance signal (or magnetization) measured by the MR imaging apparatus. Per-voxel fitting of a mathematical signal model onto the measured magnetization of the field of view in function of the phase offsets Φ. Then the spin density M0, the relaxation time ratio Λ and the local phase offset ΔΦ are determined from the fit for each voxel. A homogeneous image of the object is generated by calculating the signal intensity in each voxel, using the spin density M0 and the relaxation time ratio Λ, wherein ΔΦ is chosen such that Φ−ΔΦ=0°.