TITLE:
iShim and Water Excitation Improves the Signal-to-Noise Ratio on q-Space Imaging: A Single-Center Clinical Study
AUTHORS:
Yoshifumi Sone, Junichi Hata, Yasushi Sera, Katsuya Maruyama, Thomas Benkert, Zhouchen Lu, Jun Kasahara, Hideyuki Okano, Morio Matsumoto, Masaya Nakamura, Daisuke Nakashima, Takeo Nagura
KEYWORDS:
iShim, Fat Suppression, Water Excitation, Diffusion-Weighted Imaging, q-Space Imaging (qsi)
JOURNAL NAME:
Open Journal of Radiology,
Vol.8 No.4,
November
23,
2018
ABSTRACT: Purpose: This study aimed to examine whether the signal-to-noise ratio (SNR) could be increased by combining integrated slice-by-slice shimming (iShim) with a fat suppression (FS) method other than short-tau inversion recovery (STIR) in diffusion-weighted imaging (DWI) and q-space imaging (qsi). Methods: We acquired DWI images (b-values: 0 and nine steps from 400 to 10,000 s/mm2 for six axes) using a prototypical single-shot echo planar imaging sequence by combining two types of shimming (3D Shim and iShim) and two types of FS (STIR and water excitation [WE]) in 10 volunteers. In the DWI study, the SNR for each b-value, FS effect in the b0 image, and distortion in the added image (b0 - b10,000) were evaluated for the above-mentioned four imaging methods. qsi involved original DWI images. In the qsi study, the SNR was evaluated. Results: With regard to both 3D Shim and iShim, the SNRs were significantly higher when using WE than when using STIR in b0 - b900 images (p Conclusion: The combination of iShim and WE has a high SNR on qsi.