PROSET序列对腰骶神经根变异的显示价值:与MRM序列对照分析

Value of the PROSET sequence in the detection of lumbosacral nerve root anomalies:compare with the MRM sequence

目的:观察和探讨磁共振脊髓造影(MRM)和选择性激励技术(PROSET)序列对腰骶神经根变异(LSNRA)的显示价值及其影像表现。方法:采用常规MRI序列、3DMRM及3DPROSET序列扫描108例腰腿痛患者,MRM及PROSET序列所得图像均行3D最大密度投影重建(3D-MIP);结合原始图像及3D-MIP图像观察双侧腰骶神经根的解剖形态及走行方向。结果:在获得优良图像的105例病例中,MRM、PROSET序列分别发现LSNRA7例和14例,发现率分别为6.67%和13.33%,两者差异具有显著性(χ2=5.143,P=0.016);而常规MRI序列仅发现LSNRA3例,发现率仅为2.86%。所发现的14例变异中,Ⅱ型变异10例,占71.43%,其中Ⅱ-1型4例,占28.57%,Ⅱ-2、Ⅱ-3、Ⅱ-4型各2例,各占14.29%;Ⅲ型及Ⅵ型变异各2例,各占14.29%。结论:PROSET序列对硬膜外神经根变异的显示明显优于MRM序列,为硬膜外LSNRA的诊断提供了一种全新的方法。

Objective： To explore the application value and findings of MR myelogram （MRM） sequence and PROSET se- quence in the detection of lumbosacral nerve root anomalies （LSNRA）. Materials and Methods： Conventional MRI, 3D MRM and 3D PROSET sequences were performed in lumbosacral nerve roots of 108 cases with low back pain. 3D maximum inten- sity projection （3D-MIP） reconstruction was used in PROSET and MRM sequences. The lumbosacral nerve roots were observed in the raw images and 3D-MIP images. Results： In the 105 cases with high-quality images, LSNRA were found in the 7, 14 cases with MRM and PROSET sequence. The detection rate was 6.67% and 13.33% respectively. There were statistically sig- nificant differences between MRM and PROSET sequence （X2=5.143, P=0.016）. LSNRA were found in only 3 cases with the conventional MRI sequence. Among the 14 cases with variation, there were 10 cases of type Ⅱ （71.43%）, which was composed of 4 cases of type Ⅱ-1（28.57%） and each of the type Ⅱ-2, Ⅱ-3 and Ⅱ-4 had 2 cases（14.29% each）. There were 2 cases of type Ⅲ, 2 cases of type Ⅳ（14.29% each）. Conclusion： PROSET sequence was superior to the MRM sequence in the detection of extradural LSNRA. So it is a good method for the diagnosis of extradural LSNRA.