各向同性的3D T2 SPAIR SPACE序列在正常人肘部神经显像的应用

An isotropic three-dimensional T2 SPAIR SPACE sequence for magnetic resonance neurography in volunteers with asymptomatic elbows

目的 :观察磁共振3D T2 SPAIR(spectral adiabatic inversion recovery)SPACE序列在正常人肘部神经的显示情况,并观察其在不同人群中的显示差异。方法:在3.0 T MR下对64例正常人的2D FS-T2WI序列及3D T2 SPAIR SPACE序列平扫。对每个志愿者的3D T2 SPAIR SPACE序列的原始数据进行尺神经、正中神经及桡神经的曲面重建及最大密度投影重建,分别重建出矢状位及冠状位图像。分别统计3根神经的两种重建方法在上臂、肘关节及前臂的显示率。统计3根神经在2D FST2WI序列及3D T2 SPAIR SPACE序列上相对周围肌肉信号增高的比率。结果:64例志愿者的尺神经、正中神经及桡神经在曲面重建上可以全部清晰显示。尺神经在上臂、肘关节及前臂的最大密度投影图像上的显示率分别为92%、83%、98%,正中神经在上臂、肘关节及前臂的最大密度投影图像上的显示率分别为81%、89%、80%,桡神经在上臂、肘关节的最大密度投影图像上的显示率分别为94%、95%。尺神经信号增高在2D FS-T2WI序列上为55%,而在3D T2 SPAIR SPACE序列上仅仅为30%。结论:3D T2 SPAIR SPACE序列对正常人的肘部神经显示效果好,对正常人尺神经信号增高显示更可靠。

Objective：To evaluate the 3D T2 spectral adiabatic inversion recovery（SPAIR） Sampling Perfection with Application optimized Contrasts using different flip angle Evolutions（SPACE） sequence of elbow nerves in asymptomatic subjects by magnetic resonance neurography（MRN）,and evaluate differences between different groups. Methods：MRN imaging was performed at 3.0 T MR. All 64 subjects underwent elbow nerve MRN covering the elbow region,including T2-weighted imaging with fat suppression and the isotropic 3D T2 SPAIR SPACE. For each volunteer,thin maximum intensity projection（MIP） and curved planar reconstruction（CPR） of coronal and sagittal position through the elbow nerves from proximal to distal were obtained from the same 3D dataset.Signal intensity（SI） and MRN images of elbow nerves were evaluated at three parts：upper arm,elbow joint and forearm. The increased SI of the three nerves on FS-T2 WI and 3D T2 SPACE sequences were statistically compared to the surrounding muscle signals. Results：Images of high quality for all 64 volunteers were obtained by CPR. The neurography ratios of ulnar nerve by MIP from proximal to distal location were 92%,83% and 98%,and neurography ratios of median nerve and radial nerve were 81%,89%and 80%,as well as 94% and 95%,respectively. The increased SI of ulnar nerve on 2D FS-T2 WI and 3D T2 SPACE sequences were55% and 30%,respectively. Conclusion：The 3D T2 SPAIR SPACE sequence essentially improves the MRN of elbow nerves. SI abnormality of the ulnar nerve is more reliable on 3D SPAIR SPACE sequence.