单侧人工耳蜗植入术前后双耳残余听力变化的初步研究

目的 通过观察单侧人工耳蜗植入术后儿童双耳残余听力情况,分析其变化趋势,探讨各种可能的影响因素。 方法 将29例单侧人工耳蜗植入的重度极重度感音神经性耳聋儿童纳入研究,根据术前颞骨CT分为A组(有大前庭导水管综合征)和B组(非大前庭导水管综合征),分别于术前、术后1周、开机时、术后半年定期进行裸耳纯音测听,比较植入耳残余听力保存情况及非植入耳残余听力的变化。 结果 患儿术前双耳均不同程度存在残余听力,术后均定期行纯音测听或行为测听,各频率仍部分存有残余听力,主要分布在低频区,且随频率升高其残余听力保留率逐渐下降,各频率残余听力保留率之间差异有统计学意义(Wald χ2=16.980, P=0.001);植入耳与非植入耳各频率残余听力保留率之间差异有统计学意义(Wald χ2=10.031, P=0.002);术前后各时间节点残余听力保留率之间差异无统计学意义(Wald χ2=3.384, P=0.336); AB两组之间残余听力保留率之间差异无统计学意义(Wald χ2=0.906, P=0.341)。 结论 人工耳蜗植入对植入耳残余听力的保留主要分布在低频区;随着植入时间的延长,残余听力可以基本保持;少部分患儿行单侧植入后对非植入耳残余听力有影响;前庭导水管扩大症患儿行单侧耳蜗植入术后,非植入耳残余听力在短期内可有波动。

A preliminary study on the bilateral residual hearing after unilateral cochlear implants

Objective To investigate the influence of unilateral cochlear implantation on bilateral residual hearing.Methods A total of 29 children with severe to profound hearing loss participated in this study and were divided into two groups on the basis of pre-implantation computed tomography findings: Group A,with large vestibular aqueduct syndrome,and Group B,without large vestibular aqueduct syndrome.Pure tone audiometry and behavioral audiometry were performed pre-and post-operatively.Thresholds at 250;500;1 000;and 2 000 Hz were analyzed.Results Bilat-eral residual hearing,mainly in the low frequency region,was observed at different frequencies before and after cochlear implantation.The retention rate was decreased with the increase of frequency,and the retention rate at 2000Hz was sig-nificantly lower than that of the other frequencies.The pre-operative retention rate was statistically significant with the post-operative retention rate,but the post-operative retention rate of each time node had no statistically significant differ-ence(Wald χ2=3.384,P=0.336),the residual hearing retention rate in each time node in the implanted ear and the non-implanted ear was statistically significant(Wald χ2=0.031,P=0.002),and there was no significant difference in residual hearing between Groups A and B.Conclusion Partial residual hearing may be preserved after cochlear implan-tation in pediatric patients with severe to profound hearing loss.Residual hearing at lower frequencies was less affected than that at higher frequencies.After a prolonged period following cochlear implantation,residua l hearing remains rela-tively sta ble.Unilateral implantation had little effect on residual hearing in the non-implanted ear.Residual hearing in children with large vestibular aqueduct syndrome can fluctuate in the short term after cochlear implantation.