目的 分析腰骶神经MRI三维双向 波稳态水激发序列成像结果。方法 2017 年4月选择健康体检者30名为研究对象。 行常规MRI及三维双向波稳态水激发序列 对腰骶段脊椎进行冠状位扫描。将三维双 向波稳态水激发序列原始图像进行薄层最 大强度投影以及多平面重组。对图像进行 重建。评价左侧与右侧神经显示评分， 显示神经长度，神经节长度及宽度。结 果 所有研究对象均完成检查，未发现器 质性病变。三维双向波稳态水激发序列结 果中，腰骶神经，脊神经节，脑脊液为高 信号，骨骼肌为中等信号，骨质，脂肪， 大血管为低信号。左侧与右侧神经显示评 分、神经长度、神经节长度及宽度比较差 异无统计学意义(P＞0.05)。L5神经长度 最长，其次为S1，L4、S2。从T12到S2， 神经节宽度呈逐渐增加的趋势，自T12-S1 神经节呈长度呈增加趋势，S2有所下降。 结论 MRI三维双向波稳态水激发序列用于 腰骶神经检查能清晰显示神经主干、神经 节等情况。

Objective To analyze 3D double-echo steady-state with water excitation MRI in lumbosacral nerves. Methods 30 cases for physical examination in April 2017 were selected as subjects. All cases received 3D double-echo steady-state with water excitation MRI in lumbosacral nerves. The maximum intensity projection of the thin layer and the multiplanar reconstruction of the original image of the two-dimensional bi-directional steady state water excitation sequence are carried out. Image was reconstructed. The left and right nerve display scores, the nerve length, length and width of the ganglion were evaluated. Results All the subjects were examined and no organic lesions were found. 3D double-echo steady-state with water excitation MRI showed that the lumbosacral nerves, spinal ganglia, and cerebrospinal fluid are high signals, skeletal muscle is medium signal, and bone, fat, and large vessels are low signals. The score of nerve, length of nerve, length and width of nerve between the right and the left nerve were not statistically different(P ＞0.05). The length of L5 nerve was the longest, followed by S1, L4 and S2. From T12 to S2, the ganglion width showed a gradually increasing trend, and from T12 to S1, the ganglion length showed a gradually increasing trend, and S2 has declined. Conclusion 3D double-echo steady-state with water excitation MRI in lumbosacral nerves can clearly show the nerve trunk, ganglia and so on.