Clinial Application Of Monitering By Using Somatosensory Evoked Potentials During Lumbar Spondylolisthesis Surgery

[objective]To discuss whether it is effective to monitor the internal fixation lumbar spondy lolisthesis surgery by using the somatosensory evoked potentials (SSEP) technique of segmental dermonerve stimulation.[Methods]82 patient involving the lumbar spondylolisthesis had been surgically treated and assisted by using the SEP index of preanaesthetization. The inspection had been proceeded at pre and intra operation; a long term follow up period had been taken after operation; the retrospectivel study on the intraoperational potential changes had been performed among patients, whose function had been improved after operation. As a whole the effective assess ment index of intraoperational monitor had been established, providing reference for the lumbar spondylolisthesis surgery.[Results]Taking the SEP index value of postanesthetic patients before operation as the standard, the changes of intraoperational potential may indicate the following status: The latency period decreasing in 10%-15% or the amplitudes increasing in 40% indicated that the outlook of recovery was good enough and the prognosis was favoured.The latency period decreasing in less than 10% or the amplitudes increasing in less than 30% indicated that part of the function could be reduced.The latency period extending over 5%, and the amplitudes increasing more than 10% together with the dispersion of wave, indicated that the pain would be appeared and the dysfunction of motion would be occurred after operation. The accuracy of index may arrain to 93.75%.[Conclusions]The SSEP is a kide of quantitative and objective electrophysiological assessment for lumbar spondylolisthesis surgery, and its exact veracity and high sensitivity. The SSEP intraoperational guardianship of segmental dermonerve stimulation is the objective and effective method in lumbar in lumbar spondylolisthesis surgery.