神经反应遥测技术在人工耳蜗植入术中的监测应用

目的探讨在人工耳蜗植入术中能快速、准确地判断人工耳蜗装置的完好性和患者客观听觉反应的监测方法.方法在40例患儿人工耳蜗植入术中先测定电极阻抗,然后使用神经反应遥测技术(neuralresponsetelemetry,NRT)监测6个电极的电诱发听神经复合动作电位(electricallyevokedauditorynervecompoundactionpotentials,ECAP).结果患儿所有电极阻抗正常,ECAP的检出率分别为97.5%(39例/40例)和92.1%(221个电极/240个电极).其中33例内耳无畸形的患儿所有198个测试电极中有195个电极测出清晰的ECAP波形(98.5%).7例内耳Mondini畸形患者共42个测试电极中有26个电极测得ECAP波形(61.9%),两组之间差异有极显著性.靠近耳蜗底回(高频区)的电极比靠近蜗尖(低频区)的电极具有较高的ECAP反应阈值和较高的ECAP饱和阈值.结论NRT技术可以简便、快速和准确地判断患者的听神经反应,可望成为术中常规监测方法,内耳Mondini畸形是影响ECAP检出的重要因素.

The intraoperative application of neural response telemetry with the Nucleus CI24M cochlear implant

Objective To test device integrity and objective auditory reaction for cochlear implant patients intraoperatively. Methods Our protocol for intraoperative testing of the implant device includes device electrode impedance test and neural response telemetry (NRT), which measures the electrically evoked auditory nerve compound action potentials (ECAP). Results We completed electrode integrity tests and NRT intraoperatively on 40 patients with the Nucleus CI24M cochlear implant. We have measured normal implant function on all 40 patients and obtained ECAP results from 39 patients. Out of 33 patients with normal inner ear, typical ECAPs were recorded in 195 electrodes in all 198 testing electrodes(98.5%). In 7 patients with inner ear Mondini dysphasia, affirmative ECAP waveforms were recorded in 26 electrodes in all 42 testing electrodes. The basal electrode ECAP threshold was higher than that of the epical one. Conclusions The intraoperative measurements of device function and NRT are quite simple, quick and with high accuracy. Inner ear malformation is an important factor that may affect NRT results.