Murakami Hirohisa, Tsukube Takuro, Kawanishi Yujiro, Okita Yutaka
Division of Cardiovascular, Thoracic, and Pediatric Surgery, Department of Cardio-pulmonary and Vascular Medicine, Kobe University Graduate School of Medicine, 7-4-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.
J Vasc Surg. 2004 Jan;39(1):207-13. doi: 10.1016/s0741-5214(03)01050-4.
Myogenic transcranial motor-evoked potentials (tc-MEPs) were applied to monitor spinal cord ischemia in the repairs of thoracoabdominal aortic aneurysms. We investigated whether tc-MEPs after spinal cord ischemia/reperfusion could be used to predict neurologic outcome in leporine model.
Tc-MEPs were measured at 30-second intervals before, during, and after spinal cord ischemia (SCI) induced by balloon occlusion of the infrarenal aorta. Twenty rabbits were divided into five groups. Four groups (n = 4 animals in each group) had transient ischemia induced for 10, 15, 20, or 30 minutes. In fifth group, the terminal aorta at the aortic bifurcation was occluded for 30 minutes. All animals were evaluated neurologically 48 hours later, and their spinal cords were removed for histologic examination.
The tc-MEPs in each SCI group rapidly disappeared after SCI. After reperfusion, the recovery of tc-MEPs amplitude was inversely correlated to duration of SCI. Tc-MEPs amplitude at one hour after reperfusion was correlated with both neurologic score and number of neuron cells in the spinal cord 48 hours later. Logistic regression analysis demonstrated that the neurologic deficits differed significantly between animals with tc-MEPs amplitude of less than 75% of the baseline and those with an amplitude of more than 75%.
The amplitude of tc-MEPs after ischemia /reperfusion of the spinal cord showed a high correlation with durations of SCI, with neurologic deficits, and with pathologic findings of the spinal cord. Tc-MEPs, therefore, could be used to predict neurologic outcome. In particular, tc-MEPs whose amplitude recovered by less than 75% indicated a risk of paraplegia.
应用肌源性经颅运动诱发电位（tc-MEPs）监测胸腹主动脉瘤修复术中的脊髓缺血情况。我们研究了脊髓缺血/再灌注后的tc-MEPs是否可用于预测兔模型中的神经功能结局。
在肾下腹主动脉球囊闭塞诱导脊髓缺血（SCI）之前、期间和之后，每隔30秒测量一次tc-MEPs。20只兔子分为五组。四组（每组n = 4只动物）进行10、15、20或30分钟的短暂缺血。在第五组中，主动脉分叉处的终末主动脉闭塞30分钟。48小时后对所有动物进行神经功能评估，并取出脊髓进行组织学检查。
每个SCI组的tc-MEPs在SCI后迅速消失。再灌注后，tc-MEPs振幅的恢复与SCI持续时间呈负相关。再灌注后1小时的tc-MEPs振幅与48小时后的神经功能评分和脊髓神经元细胞数量均相关。逻辑回归分析表明，tc-MEPs振幅小于基线75%的动物与振幅大于75%的动物之间神经功能缺损有显著差异。
脊髓缺血/再灌注后的tc-MEPs振幅与SCI持续时间、神经功能缺损以及脊髓病理结果高度相关。因此，tc-MEPs可用于预测神经功能结局。特别是，振幅恢复小于75%的tc-MEPs表明有截瘫风险。
