Philips Healthcare, Cleveland, Ohio, USA.
J Magn Reson Imaging. 2009 Nov;30(5):1027-33. doi: 10.1002/jmri.21939.
To assess the feasibility of TRacking Only Navigator echo (TRON) for diffusion-weighted magnetic resonance imaging (DWI) of the liver at 3.0T.
Ten volunteers underwent TRON, respiratory triggered, and free breathing DWI of the liver at 3.0 Tesla (T). Scan times were measured. Image sharpness, degree of stair-step and stripe artifacts for the three methods were assessed by two observers.
Mean scan times of TRON and respiratory triggered DWI relative to free breathing DWI were 34% and 145% longer respectively. In four of eight comparisons (two observers, two b-values, two slice orientations), TRON DWI image sharpness was significantly better than free breathing DWI, but inferior to respiratory triggered DWI. In two of four comparisons (two observers, two b-values), degree of stair-step artifacts in TRON DWI was significantly lower than in respiratory triggered DWI. Degree of stripe artifacts between the three methods was not significantly different.
DWI of the liver at 3.0T using TRON is feasible. Image sharpness in TRON DWI is superior to that in free breathing DWI. Although image sharpness of respiratory triggered DWI is still better, TRON DWI requires less scan time and reduces stair-step artifacts.
评估在 3.0T 下仅使用跟踪导航回波（TRON）进行肝脏弥散加权磁共振成像（DWI）的可行性。
10 名志愿者在 3.0 特斯拉（T）下接受了 TRON、呼吸触发和自由呼吸 DWI 检查。测量了扫描时间。由两名观察者评估三种方法的图像清晰度、阶梯状伪影和条纹状伪影的程度。
与自由呼吸 DWI 相比，TRON 和呼吸触发 DWI 的平均扫描时间分别延长了 34%和 145%。在四个比较中的四个（两名观察者，两个 b 值，两个层面方向）中，TRON DWI 的图像清晰度明显优于自由呼吸 DWI，但不如呼吸触发 DWI。在两个比较中的两个（两名观察者，两个 b 值）中，TRON DWI 的阶梯状伪影程度明显低于呼吸触发 DWI。三种方法之间的条纹状伪影程度没有显著差异。
在 3.0T 下使用 TRON 进行肝脏 DWI 是可行的。TRON DWI 的图像清晰度优于自由呼吸 DWI。虽然呼吸触发 DWI 的图像清晰度仍然更好，但 TRON DWI 需要的扫描时间更短，并减少了阶梯状伪影。
