臂丛节后神经的三维快速自旋回波-短时反转恢复序列成像

Three dimensional sampling perfection with application-optimized contrasts by using different flip angle evolutions-short time of the inversion recovery sequence for the post-ganglionic segments of the brachial plexus

目的探讨3D快速自旋回波一短时反转恢复序列（3DSPACE-STIR）增强成像在臂丛节后神经成像中的应用价值。方法43例可疑臂丛神经病变患者，同时接受了3DSPACE-STIR平扫及增强检查，对比臂丛节后神经的信噪比（SNR）、对比噪声比（CNR）以及根、干、股、束的显示效果。对比3DSPACE-STIR平扫和增强的SNR和CNR，采用配对样本t检验；对比3DSPACE-STIR平扫和增强对根、干、股、束的显示情况，采用非参数配对Wilcoxon符号秩检验。结果与3DSPACE．STIR平扫相比，增强扫描的神经SNR差异没有统计学意义（左侧分别为37．41±7．34、36．27±7．66，t=1．574，P=0．123；有侧分别为43．85±9．56、42．34±9．74，t=1．937，P=0．073），但神经．肌肉CNR（左侧分别为24．01±6．31、26．39±6．95，右侧分别为29．31±7．84、31．77±8．85，t值分别为-3．278、-3．278，P值均〈0．01）和神经-淋巴结CNR显著提高（左侧分别为-0．84±10．51、15．35±8．02，右侧分别为-8．47±10．85、19．30±10．35，t值分别为-15．984、-15．651，P值均〈0．01），差异有统计学意义。3DSPACE-STIR增强显示根和干明显优于平扫（z值分别为-3．606、-4．472，P值均〈0．001），但显示股和束的能力与平扫类似（z值分别为-1．732、-1．414，P值均〉0．05）。在3DSPACE-STIR增强中，肿瘤性病变倾向于信号明显下降，其显示效果差于平扫。结论3DSPACE-STIR增强对臂丛神经和非肿瘤性病变的显示有明显优势，但对肿瘤性病变则可能存在不足。

Objective To evaluate the contrast-enhanced 3D sampling perfection with application- optimized contrasts by using different flip angle evolutions-short TI inversion recovery sequence （SPACE- STIR） for the imaging of the post-ganglionic segments of the brachial plexus. Methods Forty-three patients with suspected braehial plexus lesions were examined with 3D SPACE-STIR and contrast-enhanced 3D SPACE-STIR prospectively. Signal-to-noise ratios （ SNR ） , contrast-to-noise ratios （ CNR ）, and the conspicuousness of roots, trunks, divisions and cords of the brachial plexus of the two 3D sequences were retrospectively compared. Statistical analysis was performed by using student t-test and Wilcoxon rank sum test. Results Compared with 3D SPACE-STIR, contrast-enhanced 3D SPACE-STIR provided the similar SNRs （left,37.41±7.34 vs 36.27 ±7.66,t = 1. 574,P =0. 123 ,right,43.85±9.56 vs 42. 34±9.74,t = 1. 937 ,P = 0. 073 ） , but significantly higher nerve-to-muscle CNRs （ left, 24. 01 ± 6. 31 vs 26. 39± 6. 95, right,29.31 ±7.84 vs 31.77±8.85,t = -3.278, -3.278,both P〈0.01） and nerve-to-lymph gland CNRs（left, -0.84±10.51 vs 15.35 ±8.02, right, -8.47±10.85 vs 19. 30 ±10.35,t = -15.984, - 15. 651, both P 〈 0. 01 ）. The conspicuousness of roots and trunks on contrast-enhanced 3D SPACE-STIR was significantly better than that on 3D SPACE-STIR （ Z = - 3. 606, - 4. 472, P 〈 0.01 ）, while the conspicuousness of divisions and cords was similar （Z = - 1. 732, - 1. 414,P = 0. 083,0. 157 ）. The signal intensity of neoplastic lesions on contrast-enhanced 3D SPACE-STIR tended to decrease rapidly, thus the lesion conspicuousness was worse than that on 3D SPACE-STIR. Condusions Contrast-enhanced 3D SPACE-STIR has obvious advantages in displaying normal brachial plexus and revealing non-neoplasticlesions of the brachial plexus, but may be insufficient for the diagnosis of neoplastic lesions of the brachial plexus.