David C. Newitt1,
Ek T. Tan2, Thomas L. Chenevert3, Lisa J. Wilmes1,
Suchandrima Banerjee4, Luca Marinelli2, Nola M. Hylton5
1Radiology
and Biomedical Imaging, University of California, San Francisco, San
Francisco, CA, United States; 2Diagnostics and Biomedical
Technologies, GE Global Research, Niskayuna, NY, United States; 3Radiology
MRI, University of Michigan, Ann Arbor, MI, United States; 4Applied
Science Lab, GE Healthcare, Menlo Park, CA, United States; 5Radiology
and Biomedical Imaging, University of California San Francisco, San
Francisco, CA, United States
Gradient nonlinearity (GN) is a significant source of error for quantitative diffusion MRI, and the extent of GN varies with the scanner used. This confounds results from multi-center and longitudinal studies required in clinical trials. GN effects are of particular concern in breast imaging, where the anatomy has large offsets from magnet isocenter. Retrospective GN correction (GNC) was evaluated in a multi-center setting with phantoms and in normal and breast cancer subjects. GNC significantly reduced the spatial-dependence of ADC values and improved quantitative accuracy of ADC, which could in turn improve the sensitivity of cancer-detection and cancer-monitoring in diffusion MRI.