Nucleus 24CA型人工耳蜗植入后电极阻抗及T/C值变化分析

Changes of Electrode Impedance and T/C levels in Nucleus 24CA Cochlear Implant after Implantation

目的观察Nucleus 24CA型人工耳蜗植入后电极阻抗、行为反应阈值(T-level,T级)及最大舒适级(C-level,C级)的变化规律,分析其内在联系,探讨其对术后调机的指导意义。方法对81例植入Nucleus 24CA型人工耳蜗患儿,分别在术中、术后1、2、6个月进行电极阻抗阈值测试,收集术后对应T、C值,并对其变化规律及相关性进行统计学分析。结果电极阻抗值术中检测最低,术后1月开机最高,此后逐渐减低(P<0.01);自蜗顶至蜗底各通道间电极阻抗值无显著差异(P>0.05)。各电极通道T值、C值随术后时间延长逐渐增高(P<0.05),并与电极阻抗值呈线性相关。结论测定电极阻抗值是评估人工耳蜗刺激电极状态的有效手段;术后2月应同时调试T值及C值,此后则应对C值进行重点调试。

Objective To investigate changes of electrode impedance in Nucleus 24CA Cochlear implant after Implantation. Methods Electrode impedance, T level and C level were measured during operation and at 1, 2 and 6 months after the operation. Patterns of changes and their correlations were analyzed. Results Electrode impedance was at its lowest during the operation and highest at the first stimulation 1 month after the operation, followed by a gradual decrease. Electrode impedance was not significantly different at different locations. A rectilinear correlation was found between T/C level changes and electrode impedance changes. Conclusion Measuring the electrode impedance is an efficient method to evaluate the working status of Nucleus 24CA Cochlear Implant. T level and C level should both be debugged 2 months after the operation. After that, the debugging C level will be more important.