Monitoring mild impact iatrogenic spinal cord injury by using somatosensory-evoked potential: an experimental study

Abstract

：Objective To investigatethe changes of somatosensory-evoked potential(SEP)during an mild impact spinal cord injuryin rats 80 as to evaluate its potential value in prevention of such iatrogenic damage.Methods Twenty-four SD rats weighing(340±28)g were randomly divided into twogroups,ie,sham control group(only exposure without impact at C6)and injury group(mildimpact spihal cord injury at C6).SEP wss recorded in both groups.The changes of SEP inwaveform,amplitude and latency were observed and compared between groups and betweenoperations.The gross dissection and histologic analysis were performed after surgery forcomparative study. Results SEP waveforms,amplitude and latency showed no significantchange in the sham control group.In contrast,the SEP waveform and amplitude animals showedsignificant changes in the injury group after impact spinal cord injury and the amplitudewas decreased from pre-injury(1.3±0.7)μV to post-injury(0.5±0.4)μV(P 0.05).However,this abnormal change appeared in a temporary period at(5.7±3.2)minutesafter impact and lasted for about(7.1±3.3)minutes.Diffused hemorrhagic nidus could beseen in the injured cord,which was not found in the sham control group. Condusions Mildimpact spinal cord injury may induce transient abnormalities of SEP in waveform andamplitude,which requires careful monitoring in clinical practice.The sudden change in SEPmay be associated with impact and vibration damage to the spinal cord,suggesting timelyuse of protection measures for spinal cord. Key words: Spinal cord injuries; Evokedpotentials,somatosensory; Rats,Sprague-Dawley