脊髓前动脉损伤后运动诱发电位变化与病理学对照研究

Relating Motor Evoked Potentials to Pathological Outcomes after Ischemic Stroke of Anterior Spinal Artery:An Experiment in Canines

目的 :观察脊髓前动脉损伤后运动诱发电位 (MEP)变化规律 ,以及相应的病理演变。方法 :以家犬为实验动物 ,采用颈前路手术入路 ,损伤脊髓前动脉。肉眼、镜下观察脊髓病理演变过程 ,测定脊髓前动脉损伤前、后MEP潜伏期 ,同时按Tarlov法测定肌力。结果 :脊髓前动脉损伤后出现轴索断裂 ,髓鞘呈气球样空泡 ,脊髓水肿、出血 ,运动神经元变性坏死等病理性变化 ,脊髓前动脉损伤后立即出现不完全性肢体瘫痪 ,MEP潜伏期明显延长 ,3d后MEP的潜伏期有所恢复。结论 :MEP对脊髓缺血性损伤后病理变化较敏感 ,MEP能准确地反映脊髓缺血性损伤后运动功能的变化。

Objective:To observe spinal cord function changes and Pathological outcomes of spinal cord ischemia.Methods:The model of spinal cord ischemia caused by cervical anterior spinal artery injury was established in canines.The pathology of corresponding segment of each cord was observed grossly and under light microscope.All canines myodynamia in this study were evaluated according to the Tarlov's criteria.Estimated spinal cord function by the latency of the motor evoked potential (MEP).Results:After cervical anterior spinal artery injury,the spinal cord underwent sequential pathological changes including hematomyelia,edema,axonal and motor neurons degeneration or necrosis,and demyelination.Those canines with cervical anterior spinal artery injury showed incomplete paraplegia of the hind legs postoperatively,but the myodynamia restored to I degree within 3 days.The latency of the MEP delayed after cervical anterior spinal artery injury,but came back incompletly within 3 days.Conclusions:MEP could be beneficial to diagnosis of spinal cord ischemia in clinical practices.