Reduced Field of View Imaging for Twice-Refocused Diffusion EPI using a Perpendicular Refocusing Slab
نویسندگان
چکیده
Introduction: Imaging with a reduced field of view (rFOV) is a way to reduce distortion in EPI by acquiring fewer phase-encode lines. However in cases in which regions of signal lie outside the phase field of view, aliasing will occur. This problem has been addressed by suppressing the volume outside the reduced field of view [1] and also by 2D selective excitation [2]. The latter is limited by the number of slices that can be used and both methods require lengthy preparation periods. Another approach is ZOOMEPI [3,4] which uses a tilted refocusing slice, however this requires a large gap between slices. The approach presented here is similar to ZOOM-EPI, however the 180-degree pulses are titled by 90 degrees, which assures a very sharp profile of the selected band.
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