Lu Jonathan, Pang Yong, Wang Chunsheng, Wu Bing, Vigneron Daniel B, Zhang Xiaoliang
Department of Electrical Engineering and Computer Science, University of California Berkeley, Berkeley, CA, USA.
Department of Radiology and Biomedical Imaging, University of California San Francisco (UCSF).
Int Symp Appl Sci Biomed Commun Technol. 2011;2011. doi: 10.1145/2093698.2093768.
This study is an evaluation of the ratio of electric field to magnetic field (E/B), specific absorption rate (SAR) and signal-to-noise ratio (SNR) generated by three different RF transceiver coil setups: surface coil, surface coil with shielding, and microstrip using a finite discrete time domain (FDTD) simulation in the presence of a head phantom. One of our main focuses in this study is to better understand coil designs that would improve patient safety at high fields by studying a coil type that may potentially minimize SAR while examining potential changes in SNR. In the presence of a human head load, the microstrip's E/B ratio was on average smallest while its SAR was also on average smallest of the three setups, suggesting the microstrip may be a better RF coil choice for MRI concerning patient safety and parallel excitation applications than the other two coils. In addition, the study suggests that the microstrip also has a higher SNR compared with the other two coils demonstrating the possibility that the microstrip could lead to higher quality MRI images.
本研究通过在头部模型存在的情况下使用有限离散时域(FDTD)模拟,对三种不同射频收发器线圈设置(表面线圈、带屏蔽的表面线圈和微带)产生的电场与磁场之比(E/B)、比吸收率(SAR)和信噪比(SNR)进行评估。本研究的主要重点之一是通过研究一种可能在检查SNR潜在变化的同时将SAR降至最低的线圈类型,更好地理解能够在高场提高患者安全性的线圈设计。在存在人体头部负载的情况下,微带的E/B比平均最小,其SAR在三种设置中也平均最小,这表明在患者安全和平行激发应用方面,微带可能是比其他两种线圈更好的MRI射频线圈选择。此外,该研究表明,与其他两种线圈相比,微带还具有更高的SNR,这表明微带可能会产生更高质量的MRI图像。