Application value of N9-N20 interpeak latency in cervical intraspinal tumors

WEI Liangfeng; WANG Shousen; ZHENG Zhaocong; TIAN Jun; XUE Liang

Abstract：Objective The changes of N9-N20 interpeak latency of median nerve short latency somatosensory evoked potential (MN-SLSEP) in patients with cervical intraspinal tumors are investigated , and its association with prognosis of spinal cord function is discussed.Methods Twenty-two patients suffering from cervical intraspinal tumors were enrolled into study group.Meanwhile, twenty-two age-matched volunteers were selected as control group. The somatosensory evoked potential ( SEP) detection was performed at pre-operative 3 d and post-operative one month, respectively.The difference of N9-N20 interpeak latency value between two groups was compared. Comparative analysis of discrepancy was made between pre-operative and post-operative value.Study group was further divided into delayed latency group (lat+group) and normal latency group (lat group), and the relationship was explored between N9-N20 interpeak latency and prognosis of spinal cord function .Results Pre-operative N9-N20 interpeak latency of study group was significantly longer than that of control group (P<0.05).Post-operative N9-N20 interpeak latency of study group was significantly shorter than that of pre-operative value ( P<0.05). Improvement rate of spinal cord function of lat group (100.0%) was significantly higher than that of lat +group (44.4%, P<0.05).Conclusion N9-N20 interpeak latency is a dependable index to MN-SLSEP and can be used to determine the prognosis of cervical intraspinal tumors .