Abstract #4272

Chemical Shift Correction in Fat-Water Separation Using Two-Point Dixon SSFP

Yi Wang¹,², Glen Morrell², Dennis L. Parker²

¹Neurology, University of California, Los Angeles, Los Angeles, CA, United States; ²Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT, United States

SSFP sequences offer superior signal intensity in a relative short time. The potential of a dual-echo SSFP sequence has been investigated for breast imaging applications, where fat signal is separated from the water signal using the two-point Dixon technique [3]. Dual echo SSFP provides robust water-only and fat-only images in the presence of B0 and B1 inhomogeneity. Due to the sensitivity of SSFP to off resonance, short TR is needed to minimize the banding artifact. The two echoes required for the two-point Dixon fat-water separation can be acquired using a bipolar gradient. Compared to mono-polar readout, a bipolar gradient can reduce echo spacing and therefore result in more efficient readout. However, due to the opposite chemical shift, mis-registration between images from the two echoes using bipolar readouts exists. In this work, we improved the dual-echo 3D SSFP sequence by correcting the bi-directional chemical shift error in two-point Dixon fat/water separation.