Huanzhou Yu1, Ann Shimakawa1, Diego Hernando2, Catherine D. G. Hines3, Charles A. McKenzie4, Scott B. Reeder5, Jean H. Brittain6
1Global Applied Science Laboratory, GE Healthcare, Menlo Park, CA, United States; 2Departments of Radiology, University of Wisconsin, Madison, WI, United States; 3Departments of Radiology, Biomedical Engineering, University of Wisconsin, Madison, WI, United States; 4Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada; 5Departments of Radiology, Medical Physics, Biomedical Engineering, University of Wisconsin, Madison, WI, United States; 6Global Applied Science Laboratory, GE Healthcare, Madison, WI, United States
Accurate fat-fraction quantification using chemical shift based water-fat separation methods requires correction of eddy-current induced phase errors that can lead to substantial errors at low fat-fraction estimates. The undesired phase modulation can be removed by magnitude-signal based water-fat separation methods. We show that noise performance of the magnitude-based reconstruction is sensitive to echo times. Some combinations of echo times may result in poor noise performance, demonstrated by both simulations and in-vivo scans. As a result, careful design of the acquisition is required to avoid poor SNR that may lead to inaccurate fat-fraction measurement when using magnitude-based methods.