CTM诊断臂丛神经损伤的临床研究

The clinical study of computerized tomography myelography in diagnosing root avulsion of brachial plexus

目的观察脊髓造影计算机断层扫描(computerized tomography myelography,CTM)诊断臂丛神经节前与节后损伤的准确性.方法对2001年5月～2002年3月间资料完整的25例臂丛神经损伤患者行CTM检查和臂丛神经探查术,男21例,女4例;年龄4～45岁,平均24岁.所有患者腰椎穿刺成功后注入伊索显(Isovist),成人10 ml、儿童3～5 ml,1～2h后行螺旋CT检查.仰卧、颈椎伸直位,双肩向远端牵引.扫描部位为C4椎体上缘至T2椎体上缘,层厚2 am,扫描平面与远端成75°～80°角或与椎间盘平行.通过观察椎管内相应神经根前、后支的充盈缺损消失与否作为神经节前与节后损伤的判定标准,同时与臂丛神经探查术及术后随访结果进行综合分析,以确定CTM诊断的准确性.结果25例臂丛神经损伤患者,经CTM检查95个神经根,其中90个诊断准确,准确率为94.7%;电生理检测13例臂丛神经损伤患者,共检查48个神经根,41个诊断准确,准确率为85.4%,经卡方检验两者间差异无显著性意义(X2=3.48,P＞0.05).结论CTM可清晰显示椎管内臂丛神经前、后支,尤其是C5-8神经.椎管内神经前、后支充盈缺损的消失是判定臂丛神经节前与节后损伤的可靠指标.CTM是目前诊断臂丛神经节前与节后损伤的最佳方法之一.

Objective To analyze the accuracy of computerized tomography my elography (CTM) to distinguish preganglionic injury of brachial plexus from post ganglionic as compared to the supraclavicular exploration of brachial plexus, an d evalute the outcome of follow up after operation. Methods From May 2001 to Mar ch 2003, 25 patients were admitted to our hospital, which included 21 males and 4 females aging from 4 to 45 years (mean, 24 years). Nineteen patients were take n preoperative CTM and then performed nerve exploration, release or repair opera tion, which were followed up 10 to 18 months; the other 6 patients with total br achial plexus injury were taken CTM after the first operation with partial recov ery, which were followed up 15 to 36 months. Spiral computerized tomography myel ography was examined 1-2 hours after intrathecal injection of 10 ml Isovist in a dult or 3-5 ml in children into the lumbar spine. CTM was obtained from C4 to T2 with 2 mm axial slices, and the scaning angle was parallel to the cervical disc s with the patient on supine position and the cervical spine unbent, while the b oth upper limbs were drawn distally. The criteria of CTM to identify preganglion ic or postganglionic injury depended on the absence or presence of dorsal and ve ntral rootlets intradually. Results Ninty-five cervical nerve roots (C5-T1) were evaluated by CTM preoperatively in these patients with brachial plexus injury, 90 of which cervical nerve roots were correctly diagnosed, and the accuracy rate was 94.7%. However, 48 cervical roots (C5-T1) were evaluated by electrophysiolo gy detecting in 13 patients with brachial plexus injury, 41 of which cervical ne rve roots were correctly diagnosed, and the accuracy rate was 85.4%, there was n o statistically significant difference between the two methods through chi-squar e test (÷2=3.48,P >0.05). Conclusion The ventral and dorsal rootlets of brach ial plexus especially the intradual C5~8 can be demonstrated clearly by CTM. The disappearance of ventral and dorsal rootlet of C5-T1 on CTM is a reliable index to determine the avulsion of cervical nerve roots. The results suggest that CTM is one of the best method to diagnose the preganglionic or postganglionic injur y of brachial plexus.