腘窝段腓总神经及其分支MR检查方案

MR examination plan of normal peroneal nerve and branches in popliteal fossa

目的探讨腘窝段腓总神经及其分支的MR检查方案。方法对30名志愿者腘窝段腓总神经及其分支行改良斜冠状位快速自旋回波(FSE-XL)T1W、FSE-XL T2W、FSE-XL T2W+迭代分解水和脂肪回声不对称与最小二乘法估计(IDEAL)、短时反转恢复(STIR)及矢状位三维快速扰相梯度回波(3D FSPGR)+IDEAL序列扫描。分别计算并比较不同序列斜冠状位图像中腓总神经/股二头肌的CNR,对比分析斜冠状位图像显示腓总神经及其分支的评分;分析矢状位3D FSPGR+IDEAL对腓总神经及其分支的显示率。结果斜冠状位FSE-XL T1W、FSE-XL T2W、STIR、FSE-XLT2W+IDEAL序列图像的CNR总体差异有统计学意义(F=123.57,P<0.01),FSE-XL T1W、FSE-XL T2W与STIR和FSE-XL T2W+IDEA序列图像CNR差异均有统计学意义(P均<0.01);4种序列斜冠状位图像显示腓总神经总体差异无统计学意义(χ^2=0.077,P=0.942),显示腓外侧皮神经、腓深神经和腓浅神经总体差异均有统计学意义(P均<0.05)。FSE-XL T2W+IDEAL与STIR序列图像显示腓外侧皮神经、腓深神经及腓浅神经差异均有统计学意义(P均<0.05)。3D FSPGR+IDEAL对腓总神经及其分支的显示率均为100%。结论MRI可较好地显示腘窝段腓总神经及其分支,推荐采用斜冠状位FSE-XL T2W+IDEAL及矢状位3D FSPGR+IDEAL序列。

Objective To explore MR examination scheme for common peroneal nerve and its branches in the popliteal fossa. Methods Oblique coronal improved fast spin echo (FSE-XL) T1W, FSE-XL T2W, FSE-XL T2W+iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL), short time inversion recovery (STIR) and sagittal three-dimensional fast spoiled gradient-recall echo (3D FSPGR)+IDEAL scanning were performed on 30 popliteal fossa of 30 volunteers. CNR of the peroneal nerve/femoral muscles in oblique coronal images of different sequences were calculated and compared. The displaying scores of the common peroneal nerve and its branches in oblique coronal images, of sagittal 3D FSPGR+IDEAL on common peroneal nerve and its branches were all analyzed. Results The overall differences of CNR in the oblique coronal FSE-XL T1W, FSE-XL T2W, STIR, FSE-XL T2W+IDEAL had statistical significance ( F =123.57, P <0.01), of CNR between FSE-XL T1W, FSE-XL T2W and STIR, FSE-XL T2W+IDEA were also statistical significance (all P <0.01). There was no significant difference in overall scores of common peroneal nerve (χ 2 =0.077, P =0.942) among FSE-XL T1W, FSE-XL T2W, STIR and FSE-XL T2W+IDEAL, while the overall differences of the scores of lateral peroneal cutaneous nerve, deep peroneal nerve and superficial peroneal nerve among the 4 sequence images were statistical significance (all P <0.05), FSE-XL T2W+IDEAL and STIR sequence images showed statistical significance differences of lateral peroneal cutaneous nerve, the deep peroneal nerve and superficial peroneal nerve (all P <0.05). The displaying rate of 3D FSPGR+IDEAL imaging for common peroneal nerve and its branch were all 100%. Conclusion MRI can well display common peroneal nerve and its branches in the popliteal fossa with recommended FSE-XL T2W+IDEAL and sagittal 3D FSPGR+IDEAL sequences.