Emine Ulku Saritas1, Ajit Shankaranarayanan2,
Greg Zaharchuk3, Dwight G. Nishimura4
1Department of
Bioengineering, University of California, Berkeley, CA, United States; 2Applied
Science Laboratory, GE Healthcare, Menlo Park, CA, United States; 3Department
of Radiology, Stanford University, Stanford, CA, United States; 4Department
of Electrical Engineering, Stanford University, Stanford, CA, United States
The use of a 2D echo-planar RF excitation has recently been proposed for high-resolution diffusion-weighted imaging (DWI) of targeted regions. This method excites only the region of interest, while providing inherent fat suppression and contiguous multi-slice imaging. However, the number of slices that can be acquired in a single TR is limited due to the periodicity of the excitation profile. In this work, we propose significant improvements in RF pulse design to overcome this limitation, and specifically demonstrate that the coverage can be doubled without any SNR or scan time penalty. We validate the proposed method with in vivo high-resolution axial DWI of the spinal cord.