开放式和完壁式乳突根治鼓室成形术后听力学效果分析

The hearing outcomes of modified canal wall down and canal wall up mastoidectomy and tympanoplasty

目的探讨开放式和完壁式乳突根治鼓室成形术患者术后听力改善效果。方法回顾性分析2014—2017年在北京大学第三医院行开放式或完壁式乳突根治鼓室成形术且随访资料完整的88例患者,其中男45例,女43例,年龄12~68岁,术后平均随访12.3个月。88例患者中行开放式乳突根治鼓室成形术(开放式组)42例,行完壁式乳突根治鼓室成形术(完壁式组)46例。其中开放术式在临床实践中行以下改进:(1)适当扩大手术适应证,包括病变局限但属于硬化型乳突、鼓窦狭小的病例;(2)手术中严格形成碟形术腔,保留适当的面神经嵴高度;(3)术后避免乳突腔的清理,有效缩窄术腔;(4)气化型乳突转移颞肌瓣缩小术腔。观察患者术后干耳情况以及术腔大小,记录并比较二组病例术前和术后的平均纯音听阈(average pure tone threshold,PTA)及各个频率的阈值变化,应用SPSS 19.0软件对数据进行统计学分析。结果开放式组患者术后乳突腔缩窄明显,外耳道宽度接近完壁式组。开放式组与完壁式组术后PTA较术前分别降低11.4 dB和10.4 dB,差异无统计学意义(t=0.290,P=0.770);术后骨导平均值较术前分别降低1.8 dB和1.9 dB,差异无统计学意义(t=-0.076,P=0.940);术后平均气骨导差较术前分别缩短9.6 dB和8.4 dB,差异无统计学意义(t=-0.370,P=0.712)。完壁式对于1000 Hz听力的提高程度略好于开放式,其余各频率听力提高程度开放式均略好于完壁式,但差异均无统计学意义(P值均>0.05)。结论通过对适应证的调整和一系列术中、术后操作的改进,开放式乳突根治鼓室成形术可以获得与完壁术式相同的术后听力改善效果。

Objective To compare the effect of hearing improvement after canal wall down mastoidectomy and tympanoplasty(CWDM)and canal wall up mastoidectomy and tympanoplasty(CWUM).Methods 88 patients who underwent CWDM or CWUM in 2014-2017 with complete follow-up data were retrospectively studied.There were 45 males and 43 females,aged 12-68 years old,and the average follow-up time was 12.3 months.Among them,42 cases underwent CWDM and 46 cases underwent CWUM.A series of improvements were made in the clinical practice of CWDM:(1)to expand the indications properly,including limited lesions with sclerotic mastoid and narrow tympanic sinus;(2)to form disciform cavity strictly during operation in order to retain the appropriate height of facial nerve crest;(3)to avoid the cleaning of mastoid cavity in the post-operation follow up,thus the operative cavity was effectively constricted;and(4)to transfer the temporal muscle flap in pneumatic mastoid to reduce the cavity.The condition of dry ear and the size of cavity were observed after operation.The average pure tone threshold(PTA)before/after operation and threshold changes of each frequency were compared between the two groups.SPSS 19.0 software was used to analyze the data.Results The mastoid cavity of CWDM was significantly narrowed after operation and the width of the external auditory canal was close to the CWUM group.The postoperative PTA of the CWDM and CWUM group was reduced by 11.4 dB and 10.4 dB respectively,with no significant difference(t=0.290,P=0.770).The average value of bone conduction threshold after operation was reduced by 1.8 dB and 1.9 dB respectively,with no significant difference(t=-0.076,P=0.940).The mean value of ABG after operation was shortened by 9.6 dB and 8.4 dB respectively,with no significant difference(t=-0.370,P=0.712).The threshold decrease of 1000 Hz of CWUM was slightly better than that of CWDM,and the threshold decreases of the other frequencies of CWDM were slightly better than those of CWUM,however,the differences were not statistically significant(P>0.05).Conclusion Through the adjustment of indications and a series of intraoperative and postoperative improvements,CWDM can achieve the same effect of postoperative hearing improvement as CWUM.