脊髓损伤后早期减压对诱发电位影响的实验研究

目的]观察脊髓损伤后早期减压对体感诱发电位及经颅磁刺激运动诱发电位的影响，以探讨诱发电位在判断手术时机及预后中的应用价值。方法]日本大耳兔32只随机分4组。A组为对照组，不造成脊髓损伤。B、C、D组为脊髓损伤组。对每组动物于不同时间分别检测SEP、MEP。分析波形的潜伏期、峰问波幅。用后肢的Tarlov分级法作伤后运动功能评分。取脊髓标本，行组织学观察。结果]随着脊髓压迫时间的延长，SEP、MEP的潜伏期逐渐延长，波幅逐渐减小．波幅变化较潜伏期更为敏感。在恢复过程中，脊髓受压时间越短，诱发电位恢复越早。潜伏期恢复早于波幅，而且SEP恢复早于MEP，MEP的恢复早于功能评分。结论]SEP与TMS-MEP对脊髓损伤十分敏感，能较早反映脊髓损伤程度，可用于指导临床手术治疗和判断预后。

Experimental study of motor and somatosensory evoked potentials on spinal cord injury

Objective]To evaluate the validity and feasibility of somatosensory evoked potentials(SEP) and transcranial magnetic stimulation motor evoked potential(TMS-MEP) in early decompression of spinal cord injury(SCI). Method]Thirty-two rabbits fell into four groups randomly. The static load model were used to simulate human SCI. According to the compression time, the animals were divided into 4 groups (control,5min, 15min,30min). In this study, somatosensory evoked potentials (SEP) and transcranial magnetic stimulation motor evoked potential (TMS-MEP) were used to assess neurologic function. The EPs were recorded at 5min, 15min, 30min, 60min, 6 hours, 24 hours, 3 days, 7 days post-decompression and before spinal cord injury in injury groups. Latency and amplitude were measured for each wave. Tarlov behaviour score was performed before surgery and after surgery at 1,3,7 days. Histologic studies were performed on part of animals. Result]Spinal cord compression resulted in a gradual increment in the peak latency and significant decrement in the peak amplitude. After decompression, the recovery of the latency was more obvious than the amplitude in all injury groups, EPs recovered earlier than Tarlov score. Conclusion]EPs may evaluate the neurologic function of SCI models sensitively and impartially. Dcompression early may promote SCI recovery.