Nucleus24型人工耳蜗植入后的电极有效性

目的：随访耳蜗植入后出现蜗外电极或坏损电极的情况，评价人工耳蜗植入后电极的有效性。方法：1998年6月至2002年8月53例Nucleus CI24M型耳蜗植入者，在术中及术后映射调图时进行电极阻抗测试，确定有无电极坏损及其坏损时间。开机时拍摄耳蜗位X线平片，确定电极是否完全植入。分析手术过程和术者经验对电极有效性的影响。结果：电极出现坏损的比例为13．2％，电极在术中插拔两次以上而造成电极坏损的危险度为0．4656。4年累积生存率达96．2％。不完全植入的比例为15．1％，其中又以耳蜗形态异常者居多(7／11)。结论：Nucleus CI24M型植入体在开机1～4年内的可靠性较高。电极序列在术中插拔两次以上，是导致电极坏损的主要原因。患者耳蜗的纤维化、畸形以及术者经验等因素可能导致电极不完全插入。

Efficiency of electrodes of Nucleus CI24M cochlear implant

Objective:To evaluate the efficiency of the electrodes of Nucleus CI24M through half year fellow up observation about the impaired and extra cochlear electrodes Methods: 53 patients implanted with Nucleus CI24M between June 1998 and August 2002 participated in this study The impedances of electrodes were measured intra operatively and at each mapping visits The impedance test detected the short or open circuit electrodes in the arrays The first detection time of these problem electrodes since surgery were used to calculate the cumulative survival percentage Postoperative cochlear view radiography at initial stimulation was used to determine part insertion or full insertion of the electrode array The influence of surgical procedure and surgeon's implant experiences were analyzed Results: Percentage of cases with even one impaired electrode was 13 2%; the risk ratio of re insertion for electrode impairment was 0 4656 Part implantation occurred in 15 1% patients, most of them (7/11) showed cochlea malformation The cumulative survival percentage after 4 years use was 96 2% Conclusion: Nucleus CI24M achieves a very high reliability in 1 4 years device use The re insertion during the surgery would like to cause the impairment of the electrodes The cochlea's fibrosis, malformation, and surgeon's implant experience are the main reasons of the part insertion of the electrode array