Burgess R E, Yu Y, Abduljalil A M, Kangarlu A, Robitaille P M
Department of Radiology, The Ohio State University, Columbus 43210, USA.
Magn Reson Imaging. 1999 Oct;17(8):1099-103. doi: 10.1016/s0730-725x(99)00072-7.
A radio frequency (RF) and gradient spoiled fast low angle shot technique was used to acquire images from the human brain at 8 Tesla. The resulting FLASH images, obtained with a 17 degrees nutation, a 70 ms repetition time, and a 17 ms echo time, displayed an average signal-to-noise ratio (SNR) of 220:1 (slice thickness 2.2 mm, field-of-view 24 cm, matrix 256 x 128). These images were compared with images obtained at 1.5 Tesla using identical parameters yielding a signal-to-noise of less than 10:1. As such, the 8 Tesla images display a remarkable improvement in SNR with increasing field strength. The images also show little evidence of susceptibility distortion, chemical shift, or RF penetration limitations.
采用射频（RF）和梯度扰相快速低角度激发技术在8特斯拉场强下采集人脑图像。通过17度的章动角、70毫秒的重复时间和17毫秒的回波时间获得的快速低角度激发（FLASH）图像，其平均信噪比（SNR）为220:1（层厚2.2毫米，视野24厘米，矩阵256×128）。将这些图像与使用相同参数在1.5特斯拉场强下获得的图像进行比较，后者的信噪比小于10:1。因此，随着场强增加，8特斯拉场强下的图像在信噪比方面有显著改善。这些图像也几乎没有显示出易感性畸变、化学位移或射频穿透限制的迹象。
