Schindera Sebastian T, Merkle Elmar M, Dale Brian M, Delong David M, Nelson Rendon C
Department of Radiology, Duke University Medical Center, Duke North-Room 1417, Erwin Road, Durham, NC 27710, USA.
Acad Radiol. 2006 Oct;13(10):1236-43. doi: 10.1016/j.acra.2006.06.018.
The purpose of this study was to calculate the gain in signal-to-noise ratio (SNR) of four human abdominal tissues at 3.0 Tesla (T) compared with standard 1.5 T and to validate this calculation in vivo.
The expected gain in SNR at 3.0 T in the liver, pancreas, spleen, and kidney compared with standard 1.5 T was approximated theoretically for a T2-weighted HASTE (half-Fourier acquisition single-shot turbo spin-echo) and a T1-weighted gradient-echo in- and opposed-phase sequence. Fifteen healthy male subjects underwent abdominal MR imaging using a 1.5 T and 3.0 T scanner. Coronal T2-weighted HASTE images and axial T1-weighted gradient-echo in- and opposed-phase images were acquired using the sequence parameters optimized by the vendor.
Except for opposed-phased imaging of pancreatic tissue, in vivo adjusted SNR values of all abdominal tissues were significantly higher at 3.0 T for all sequences (P < .05). The highest overall gain in SNR was achieved with the HASTE sequence ranging from 3.8-fold for renal imaging to 7.4-fold for hepatic imaging. The theoretical calculation of SNR gain was in good agreement with the experimentally measured gain in SNR for the HASTE and the in-phase sequence.
High-field abdominal MR imaging at 3.0 T offers significantly higher SNR compared with standard 1.5 T MR imaging.
本研究的目的是计算与标准1.5T相比，四种人体腹部组织在3.0特斯拉（T）时的信噪比（SNR）增益，并在体内验证该计算结果。
对于T2加权HASTE（半傅里叶采集单次激发快速自旋回波）和T1加权梯度回波同相和反相序列，理论上近似计算了与标准1.5T相比，肝脏、胰腺、脾脏和肾脏在3.0T时的预期SNR增益。15名健康男性受试者使用1.5T和3.0T扫描仪进行腹部磁共振成像。使用供应商优化的序列参数采集冠状位T2加权HASTE图像和轴位T1加权梯度回波同相和反相图像。
除胰腺组织的反相成像外，所有序列在3.0T时所有腹部组织的体内调整后SNR值均显著更高（P < 0.05）。HASTE序列实现了最高的总体SNR增益，范围从肾脏成像的3.8倍到肝脏成像的7.4倍。SNR增益的理论计算与HASTE和同相序列的实验测量的SNR增益高度一致。
与标准1.5T磁共振成像相比，3.0T的高场腹部磁共振成像提供了显著更高的SNR。
