三维快速自旋回波序列3.0 T磁共振成像在大鼠脊髓全截断模型中的应用

Application of 3.0 T magnetic resonance imaging with three-dimensional fast-spinecho sequence in a rat model of complete spinal cord transection

目的:探讨三维快速自旋回波序列(即CUBE序列)3.0 T磁共振成像(MRI)在大鼠脊髓全截断模型中的成像效果。方法:选取6只Sprague Dawley(SD)大鼠构建T9脊髓全截断实验动物模型,监测术后运动功能,术后第1周和第8周在3.0 T场强下采用快速自旋回波(FSE)序列和CUBE序列对脊髓截断部位进行扫描,比较两者成像效果,同时计算脊髓缺损体积,并基于CUBE序列进行脊髓三维重建。结果:与FSE序列(层厚1.00 mm)相比,CUBE序列的层厚更薄(0.20 mm),可在14~18层图像上显示脊髓截断部位及中央管、神经根等邻近正常脊髓等结构。基于超薄层厚的CUBE序列实现了对脊髓截断节段的三维重建。功能恢复方面,脊髓缺损体积变化与大鼠术后运动功能恢复情况一致。结论:CUBE序列3.0 T MRI较FSE序列更适用于大鼠脊髓全截断模型的高分辨率超薄层厚成像和三维重建。

Objective:To investigate the imaging efficacy of three-dimensional(3D)fast-spin-echo sequence(CUBE sequence)of 3.0Tesla magnetic resonance imaging(3.0 T MRI)in a rat model of complete spinal cord transection.Methods:Six Sprague-Dawley rats were used to establish a T9 complete spinal cord transection model.Postoperative motor recovery was monitored,and a 3.0 T MRI imaging was implemented at the transection site using the fast-spin-echo(FSE)and CUBE sequences at the first and eighth weeks after surgery.The imaging outcomes of the two sequences were compared,the volumes of injured spinal cord segments were calculated,and 3D reconstruction of the spinal cord was conducted based on CUBE sequences.Results:Compared with FSE sequences(slice thickness 1.00 mm),CUBE sequences offered a thinner slice thickness(0.20 mm),enabling visualization of the transected areas and adjacent normal myeloid structures such as central canals and neural roots in 14 to 18 slices.Besides,the CUBE sequence with ultrathin slices enabled 3D reconstruction of the transected spinal cord segments.In terms of functional recovery,the volume changes of the defective spinal cord were consistent with the recovery of motor function in rats postoperatively.Conclusions:The 3.0 T MRI of the CUBE sequence is superior to the FSE sequence for high-resolution ultra-thin imaging and 3D reconstruction in a rat model of complete spinal cord transection.