PASTA++: B1- and T1-robust fat suppression at 3T
نویسنده
چکیده
To demonstrate the PASTA++ technique, sagittal and axial slices of the lower lumbar of a female volunteer was scanned under IRB protocol on a Toshiba 3T whole-body research system. Second order shims were used to improve B0 homogeneity. We used PASTA++ with FSE readout with the following parameters: TE/TR = 92/3000 ms, echo space = 7.0 ms, ETL = 23, matrix = 256 x 256, FOV = 25.6 x 25.6 cm, 5 slices, readout BW = 434 Hz/pixel, and 2 averages. Slice thickness was 4 mm in sagittal and 5 mm in axial images. The initial echo space was 8.0 ms to accommodate the longer excitation pulse as described above. For comparison, analogous CHESS images were acquired with identical parameters except TE = 91 ms, the slight difference due to regular echo spacing. SNR was measured in ROI at several locations in each image set. Fig 1. Slice displacement of fat excitation selection [blue hash] and refocus selection [orange hash] relative to water selection [gray] for PASTA and PASTA++. Center of water selection is marked by 0 on slice-select [SS] axis. PASTA++: B1and T1-robust fat suppression at 3T
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