Three-dimensional water/fat separation and T2* estimation based on whole-image optimization: application in breathhold liver imaging at 1.5 T
2012 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 67, no 6, 1684-1693 p.Article in journal (Refereed) Published
The chemical shift of water and fat resonances in proton MRI allows separation of water and fat signal from chemical shift encoded data. This work describes an automatic method that produces separate water and fat images as well as quantitative maps of fat signal fraction and T2* from complex multi-echo gradient recalled datasets. Accurate water and fat separation is challenging due to signal ambiguity at the voxel level. Whole-image optimization can resolve this ambiguity, but might be computationally demanding, especially for three-dimensional (3D) data. In this work, periodicity of the model ﬁt residual as a function of the oﬀ-resonance was utilized to modify a previously proposed formulation of the problem. This gives a smaller solution space and allows rapid optimization. Feasibility and accurate separation of water and fat signal was demonstrated in breathhold 3D liver imaging of ten volunteer subjects, with both acquisition and reconstruction times below 20 seconds.
Place, publisher, year, edition, pages
2012. Vol. 67, no 6, 1684-1693 p.
water and fat separation, chemical shift imaging, quantitative MRI, liver fat, T2* mapping, QPBO
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-158097DOI: 10.1002/mrm.23185ISI: 000304086000020PubMedID: 22189760OAI: oai:DiVA.org:uu-158097DiVA: diva2:437951