人工耳蜗植入儿童1000 Hz探测音ESR测试刺激持续时间的研究

Study on Optimal Setting of Stimulus Duration in ESR Measurement with 1000 Hz Probe Tone for Cochlear Implant Users

目的探讨人工耳蜗植入术后1000 Hz探测音电诱发镫骨肌反射(electrically evoked stapedius reflex,ESR)测试中刺激持续时间的最佳设置,及其阈值(electrically evoked stapedius reflex threshold,ESRT)与最大舒适阈值(most comfortable level,MCL值)之间的关系。方法选取植入MED-EL SonataTi100型人工耳蜗的患儿21例(年龄2~11岁,平均7.80±2.21岁,人工耳蜗至少使用一年且效果良好)。对17例受试者进行刺激持续时间分别为300、500、800和1000 ms的1000 Hz探测音ESR测试,对其余4例受试者进行500 ms刺激持续时间的ESR测试,测试电极为2、6、11号电极,获取相应的ESRT,并记录相应电极的MCL值。对三个电极四种刺激持续时间的ESRT进行重复测量方差分析,对500 ms刺激持续时间的ESRT和MCL值进行相关性和线性回归分析。结果21例受试者500 ms刺激持续时间的ESR总引出率为90.48%(57/63)。17例受试者每个电极300 ms刺激持续时间的ESRT均显著高于500、800和1000 ms刺激持续时间的ESRT(P<0.05);而每个电极500、800及1000 ms刺激持续时间的ESRT之间均无显著差异(P>0.05);每种刺激持续时间的三个电极之间的ESRT差异有统计学意义(P<0.05),11号电极的ESRT最大,6号次之,2号最小。500 ms刺激持续时间的三个电极的ESRT与MCL值均显著相关(P<0.01)。结论人工耳蜗植入儿童1000 Hz探测音ESR测试中推荐使用≥500 ms的刺激持续时间,其阈值可指导MCL值的调试。

Objective To study the optimal setting of stimulus duration in electrically evoked stapedius reflex(ESR)measurement with high-frequency(1000 Hz)probe tone after cochlear implantation,and the relationship between electrically evoked stapedius reflex threshold(ESRT)and most comfortable level(MCL).Methods Twenty-one pediatric patients(implanted with a MED-EL SonataTi100 cochlear)participated in this study.They had been using the cochlear for at least a year with good results and considerable ability of communication,and could cooperate with subjective and objective tests.ESR measurements with high-frequency(1000 Hz)probe tone were performed on 17 participants,whose stimulus durations were setted at 300,500,800 and 1000 ms,respectively.The remaining 4 participants were tested for the stimulus duration of 500 ms.Three cochlear electrods of 2,6,11 were selected for the ESR measurement.The corresponding ESRT was Obtained after tests and the MCL of the corresponding electrod was recorded in the common program.Then repeated measurement analysis of ANOVA was performed for ESRTs of three tested electrods with four stimulus durations,and correlation and linear regression analysis were performed for ESRTs with 500 ms stimulus duration and MCLs.Results The total elicitation rate of ESR measurement was 90.48%(57/63)in 21 participants with 500 ms stimulus duration.The ESRTs of each tested electrode under the condition of 300 ms stimulus duration were significantly higher than those of under the conditions of 500 ms,800 ms and 1000 ms stimulus durations(P<0.05).There were no significant differences among ESRTs of each tested electrode under the conditions of 500,800 and 1000 ms stimulus durations(P>0.05).There were significant differences among ESRTs with electrodes of 2,6,11 under the condition of each stimulus duration(P<0.05).The ESRTs of electrode 11 were the largest and those of electrode 2 were the smallest.There were significant correlations between ESRTs with 500 ms stimulus duration and MCLs of three electrodes(P<0.01).Conclusion Stimulus durations≥500 ms are recommended for ESR measurement with high-frequency(1000 Hz)probe tone.ESRT with high-frequency(1000 Hz)probe tone could guide the setting of MCL after cochlear implantation.