脊髓型颈椎病手术中体表感觉诱发电位(SSEP)检测对术后疗效的预测作用

Value of SSEP(somatosensory evoked potentials) in predicting outcome of operation for cervical spondylotic myelopathy

[目的]探讨SSEP检测在颈椎病手术中对术后疗效的预测作用。[方法]回顾性分析61例颈椎病患者术中SSEP检测结果与术后疗效的关系。其中前路手术41例,后路手术20例。SSEP分别检测潜伏期和波幅,与基线对比,10%潜伏期或50%波幅变化分别定义为阳性结果。对于每个参数,病人分为3组:改善、无变化和加重。分别在术前、术后3 d、3个月和12个月对患者进行JOA评分,使用恢复率[(术后JOA评分-术前JOA评分)/(17-术前JOA评分)×100%]作为术后功能评测指标。[结果]31例(51%)波幅改善,术后3 d、3个月、1年JOA恢复率分别是(56.56±10.13)%,(58.45±11.67)%,(59.36±10.56)%;30例(49%)波幅无变化,术后3 d、3个月、1年JOA恢复率分别是(46.54±9.56)%,(49.26±9.67)%,(50.26±10.56)%,两组恢复率具有统计学意义(P<0.05),没有波幅减小者。10例(16%)发生潜伏期延长,20例(33%)潜伏期无变化,31例(51%)发生潜伏期减少,这三组患者术后3 d、3个月、1年JOA恢复率无统计学差异。[结论]SSEP波幅的变化对于颈椎病手术中脊髓减压的效果较为敏感,可以用来预测术后功能恢复程度;而潜伏期的变化影响因素较多,不能准确预测疗效。对于长期疗效的预测作用有待进一步观察。

[ Objective] To determine the utility of intraoperative SSEP monitoring in predicting outcome of operation for cervical spondylotic myelopathy. [ Methods ] Sixty - one cases of operation for cervical spondylotie myelopathy were retrospectively analyzed, including 41 cases of ACDF, 20 cases of posterior laminoplasty, SSEP monitoring was used during operation, 10% change of latency or 50% change of amplitude compared with baseline were defined as positive results, respectively. For each parameter, the patients were divided into 3 groups： improved, unchanged and aggravated group. JOA score was obtained for each group before operation and at 3 days, 3 months and 12 months after operation. Recovery rate [ 100 × （ postoperative JOA score - preoperative JOA score） / （ 17points - preoperative JOA score） ] was used to evaluate the outcome. [Results] The amplitude of 31 cases （51%） improved, recovery rate of JOA at 3 days, 3 months and 12 months after operation were （56. 56 ± 10. 13）% , （58.45± 11. 67）% , and （59. 36 ± 10. 56）% respectively. The amplitude of other 30 cases （49%） unchanged, recovery rate of JOA was （46. 54± 9.56） % , （49.26 ± 9. 67 ） % , and （ 50. 26±10. 56 ） % , the difference between these two groups was statistically significant （P 〈 0. 05 ） . There was no amplitude deteriorated. The latency of 10 （ 16% ） cases prolonged （aggravated）, 20 （33%） cases unchanged, 31 （51%） cases decreased （improved） . There is no significant difference with recovery rate of JOA among these 3 groups. [ Conclusion] The change of wave amplitude is sensitive to the decompression of spinal cord during operation for cervical spondylotic myelopathy, and is useful to predict the degree of postoperative recovery; while the latency of SSEP is not reliable to predict the outcome. The long term effect needs further investigation.