置换部分听骨赝复物后对人耳听力恢复的影响

Effect of partial ossicular prosthesis replacement on hearing restoration of human

目的探讨听骨部分置换术中不同的置换方式对患者术后听力的影响。方法根据人体正常右耳CT扫描结果,用自编程序将CT扫描数值化并导入PATRAN重建人耳三维有限元模型,对其进行声音传导动力分析,并与试验数据对比。结果通过正常人耳结构动力响应分析结果与实验数据吻合,验证了模型的正确性;在0.1～10 kHz频率下保留部分锤骨柄置换人工听骨比不保留锤骨柄术后听力恢复更好,听力恢复值在11.56～28.91 dB之间;保留部分锤骨柄时鼓膜处的最大应力值比不保留锤骨柄时更小;厚2.0 mm软骨片在0.1～0.6 kHz,2～10 kHz频率上听力恢复较好;厚0.1 mm软骨片在0.6～2 kHz频率上听力恢复较好。结论在听骨部分置换术中,保留部分锤骨柄比不保留锤骨柄听力恢复效果更好;鼓膜与人工听骨的接触面上垫置的软骨片厚度在0.1～2.0 mm之间对人耳听力恢复效果较好。

Objective To study the postoperative effects on hearing restoration after different types of ossicular reconstruction with partial ossicular replacement prosthesis（PORP）.Methods CT data of the right ear from a healthy volunteer were digitalized and imported into PATRAN software to reconstruct the 3D finite element model of the ear by a self-compiling program.Dynamic analysis was conducted on the sound transmission to make comparison between the calculated results and experimental data.Results Results of the dynamic analysis for normal human ear were in good agreement with the experiment data,which confirmed the validity of the FE model.At the frequency between 0.1-10 kHz,hearing restoration with partial retaining the handle of malleus was better than that without retention after the replacement of PORP,and the value of hearing restoration was between 11.56-28.91 dB.The maximum stress of tympanic membrane with partial retaining the handle of malleus was less than that without retaining.At the frequency between 0.1-0.6 kHz as well as between 2-10 kHz,better hearing restoration was obtained when the thickness of the cartilage slice was 2.0 mm.At the frequency between 0.6-2 kHz,better hearing restoration was obtained when the thickness of the cartilage slice was 0.1 mm.Conclusions For ossicular reconstruction with PORP,the effect of retaining the handle of malleus was much better than that without retaining.The effect of hearing restoration was better when the thickness of the cartilage placed between the tympanic membrane and the contact surface of the PORP was within the range of 0.1-2.0 mm.