兔坐骨神经急性挤压伤的MRI成像序列优选

MRI Sequence Optimizing for Acute Sciatic Crush Injury in Rabbits

目的:探讨兔坐骨神经急性挤压伤的MR I成像最佳序列及其可行性,为MR I研究动物外周神经损伤提供客观基础。方法:24只新西兰白兔左下肢作为损伤侧,建立坐骨神经急性挤压伤模型,右下肢为假手术侧,于损伤后1周对所有动物坐骨神经进行MR I扫描,扫描序列包括:T1W I、3DT2W、IT2W I/SPIR、STIR、T2W I/SPAIR,观察各序列对损伤侧坐骨神经近、远段显示情况。结果:损伤侧坐骨神经术后1周在T1W I上未见异常变化,3DT2W I、T2W I/SPIR、STIR、T2W I/SPAIR上挤压伤远段神经明显增粗,信号增高,挤压伤近段所有序列未见异常改变。3DT2W、IT2W I/SPIR、STIR、T2W I/SPAIR对损伤神经远段的显示分别为95.65%(23/24)、60%(15/24)、70.83%(17/24)、60%(15/24),提示3DT2W I对损伤神经的显示明显高于其他三序列(P<0.05),其他三序列对损伤神经的显示无统计学差异(P>0.05),但STIR序列的图像较SPIR、T2W I/SPAIR清晰。结论:3DT2W I对损伤神经显示率明显高于其他三个序列,常规MR I可以清晰显示兔坐骨神经损伤,3DT2W I及STIR序列是显示外周神经损伤最好的序列。

Objective：To evaluate the feasibility of MRI sequence optimising for detection of acute sciatic crush injury in rabbits and to provide evidence for using MRI in studies of animal peripheral nerve injuries. Methods： Twenty-four rabbits were rendered acute sciatic crush injury on the left lower limb, with the right sciatic nerve serving as a sham - operation control. At 1 week after injury, MRI imaging of all sciatic nerves were performed in T1WI, 3DT2WI, T2WI/SPIR, STIR and T2WI/SPAIR sequences. Visualization of these sequences for distal and proximal segments of the sciatic lesion was also evaluated. Results ： At 1 week after injury, T1WI did not show any abnormalities on the crushed side, while 3DT2WI, T2WI/SPIR, STIR and T2WI/SPAIR revealed significant, hyperechoic thickening distal to the lesion. Unremarkable changes were found at the proximal segments with all sequences. The rates of distal visualization with 3DT2WI, T2WI/SPIR, STIR and T2WI/SPAIR were 95.65% （23/24）, 60% （ 15/ 24）, 70. 83% （17/24） and 60% （15/24）, respectively, suggesting higher performance of display by 3DT2WI compared with the others （ P 〈 0.05 ）. On the other hand, there was no difference in lesion visualization among T2WI/ SPIR, STIR and T2WI/SPAIR （ P 〉 0.05 ）, except that STIR imaging appeared clearer than with SPIR and T2WI/ SPAIR. Conclusion： 3DT2WI may provide better display for nerve injury than other sequences. While routine MRI appears suitable to clearly show sciatic injury in rabbits, 3DT2WI and STIR may be the optimal choice of sequences for this purpose .