骨桥在双侧先天性外中耳畸形中应用的初步研究

The implantation of Bonebridge in bilateral congenital malformation of external and middle ear

目的 对双侧先天性外中耳畸形患者骨桥植入术后的听力效果进行评估.方法 11例双侧先天性外中耳畸形患者均行单侧骨桥植入,其中男6例,女5例;年龄8 ～ 26岁,平均16.9岁.术后7～10d首次调试.分别测试在声场中裸耳与骨桥助听下的平均听阈（0.25、0.5、1、2、4 kHz）.＞12岁的植入者应用普通话测听词汇表（Mandarin Speech Test Materials,MSTM）,其余采取普通话儿童词汇相邻性测试词表（Mandarin Lexieal Neighborhood Test,MLNT）进行言语识别率（speech discrimination scores,SDS）测试.采用SPSS 17.0统计软件分析比较裸耳与骨桥植入听力效果的差异,评价骨桥对听力的增益程度.结果 骨桥植入后裸耳骨导听阈与术前相比无变化,声场中骨桥助听听阈较裸耳听阈改善了25 ～ 35 dB.言语测听,＞12岁组SDS改善50％左右;≤12岁组2例患者在骨桥助听下SDS亦较裸耳有所改善.统计学分析显示,裸耳与骨桥植入在声场听阈及SDS上差异均有统计学意义（P值均＜0.05）.结论 骨桥改善双侧先天性外中耳畸形患者听力效果显著,能为此类患者听力重建提供新的选择.

Objective To evaluate the auditory efficacy of Bonebridge implantation in patients with bilateral congenital malformation of external and middle ear.Methods Eleven cases （6 males and 5 females） had unilateral Bonebridge implantation.The age ranged from 8 to 26 and the average age was 16.9.Seven to ten days after operation,the first fitting was undergone.In acoustic sound field,the average auditory thresholds were respectively measured for unaided ears and Bonebridge implanted ears by pure tone auditory （PTA,0.25,0.5,1,2 and 4 kHz）.For the group over 12-year-old,MSTM was applied to evaluate speech discrimination score （SDS）.For the other cases,MLNT was used as the test material.The auditory efficacy post Bonebridge implantation would be analyzed and evaluated by comparing the differences between unaided ears and Bonebridge implanted ears.Results The bone conduction audibility threshold after Bonebridge implantation was as well as the preoperative.The auditory threshold with Bonebridge aided was improved to 25-35 dB HL,when compared to that of the unaided ears in the sound field.The SDS in the group over 12-year-old was improved about 50%;the efficacy was slightly limited for the other two cases （both less than 12 years old）.Statistical analysis showed that there were significant differences between unaided ears and Bonebridge implanted ears in the sound field and SDS （P 〈 0.05）.Conclusions The auditory efficacy of Bonebridge is significant and noticeable in patients with bilateral congenital malformation of external and middle ear.Bonebridge provides a new and effective way for patient with congenital malformation of external and middle ear to reconstruct hearing.