Two‐point Dixon technique for water‐fat signal decomposition with B0 inhomogeneity correction

To separate water and lipid resonance signals by phase‐sensitive MRI, a two‐point Dixon (2PD) reconstruction is presented in which phase‐unwrapping is used to obtain an inhomogeneity map based on only in‐phase and out‐of‐phase image data. Two relaxation‐weighted images, a “water image” and a “fat image,” representing a two‐resonance peak model of proton density, are output. The method is designed for T1‐ or density‐weighted spin‐echo imaging; a double‐echo scheme is more appropriate for T2‐weighted spin‐echo imaging. The technique is more time‐efficient for clinical fat‐water imaging than 3PD schemes, while still correcting for field inhomogeneity.