儿童人工耳蜗植入术后神经反应遥测阈值的变化

目的:通过对儿童患者术后神经反应遥测 (NRT) 阈值的分析,总结其变化规律,为儿童人工耳蜗植入术后调试提供帮助.方法:测试40例接受Nucleus CI24R 型多导人工耳蜗单侧植入术的患儿.测试使用澳大利亚Cochlear公司提供的便携式调试系统及NRT3.1版本软件.采用削减算法提取NRT反应波形,分别测试每位患者的第1、5、10、15、20号电极,NRT阈值使用NRT软件计算.分别在开机时、开机3、6和12个月时进行测试.结果:在术后同一测试时间,位于耳蜗不同部位电极的NRT阈值存在差异.耳蜗底部和顶部电极的NRT阈值较低,而位于耳蜗中部的电极NRT阈值较高.经单因素方差分析,不同部位NRT阈值均差异有统计学意义.同一测试电极,随术后开机时间的增长,NRT阈值呈逐渐增加的趋势.经单因素方差分析,术后不同测试时间NRT阈值均差异有统计学意义.结论:术后开机1年内,NRT阈值呈逐渐增加的趋势.若人工耳蜗植入术后调试需要NRT进行辅助,每次均应测试NRT阈值,以便更准确估算患者的行为反应T、C级,尤其对植入术后1年内的儿童患者更为重要.

The change of neural response telemetry thresholds in children with cochlear implant

Objective:To investigate the change of neural response telemetry(NRT) thresholds in children with cochlear implant postoperatively and to summarize how to use NRT thresholds during the mapping sessions after cochlear implant.Method:Forty children implanted with the Nucleus CI24R multiple cochlear implant system from 2004 to 2005 were involved in this study.The hardware used in this study was portable programming system(PPS) provided by Cochlear Limited in Australia and the software was NRT 3.1.Subtraction method was used to record NRT responses and the software calculated the NRT thresholds automatically.No.1,5,10,15,20 electrodes were tested during the switch-on session and 3,6,12 month after the switch-on session.Result:There were variations in the NRT thresholds of different electrodes at the same session.The NRT thresholds of the basal and apical electrodes were lower than that of the middle electrodes.There were significant differences of the NRT thresholds among different electrodes.The NRT thresholds of the same electrode increased during subsequent mapping session.There were also significant differences of the NRT thresholds among different sessions.Conclusion:The results suggested that the NRT threshold changes occur in children within the first year after cochlear implant.It is better to test the NRT thresholds during the same mapping session rather than during the operation time or during the switch-on session to set T and/or C levels at later visits,especially for the children within the first year after operation.