先天性外耳道異常之治療

Treatment of Congenital Anomalies of the External Auditory Canal

徐銘燦(Min-Tsan Shu) ； 林鴻清(Hung-Ching Lin) ； 陳昱君(Yu-Chun Chen)

《台灣耳鼻喉頭頸外科雜誌》 39卷3期 (2004/06) Pp. 98-103

https://doi.org/10.6286/2004.39.3.98

摘要

背景：先天性外耳道狹窄或閉鎖，常伴有中耳構造及顏面神經走向異常的問題，手術時可能造成顏面神經的損傷和感音性的聽力傷害，因此手術對手術的醫師來說是一大的挑戰。國內對此種手術的經驗報告不多，我們主要就此類病人的手術結果作一探討。
方法：用回顧性的方式，從1986年11月至2002年8月，以先天性外耳道狹窄或閉鎖的手術病例為研究對象，我們經歷了34例36耳的手術經驗。手術方法包括耳道成形術、鼓室成形術、聽小骨重建術、開放腔乳突鑿開術和耳道封閉手術。手術的第1種情形是因伴有膽魯瘤並產生併發症，以手術去除膽脂瘤來控制發炎為目的，共有5耳。第2種情形是為矯正聽力而接受耳道成形手術，共有29例31耳。
結果：接受第1種情形手術的5例中，有1耳是耳道術，3耳是開放腔乳突鑿開術，1耳是耳道封閉手術。第2種情形是接受耳道成形手術的29例31耳，年紀從4歲到32歲，中位數之年齡為11歲，主要分佈在4到10歲共有15耳佔48％。有2耳在術中發現有膽脂瘤。術後有2例追蹤失敗。術後聽力沒改善的有4耳，改善的有25耳。平均氣導從術前的61.7dB，變為術後的33.5dB，改善了28.2dB。術後氣導有10耳在25dB內，有12耳介於26dB和40dB之間。大約71%（22／31）的患者術後變得更差。全部病例的聽小骨有多重不同程度的異常，包括槌骨側突、前突和閉鎖板（atretic plate）相固著、槌骨柄變短、槌骨砧骨關節固著、砧骨長突較細、豆狀突消失、鐙骨上部構造變細、變形及足板固著。術後追蹤的併發症，有耳道口因疤痕而變窄、外耳道肉芽組織、鼓膜外移、耳垢堆積和耳道口不規則的新生骨。全部的患者術後都沒發生顏面神經麻痺。
結論：先天性耳道異常的手術，對醫師來是充滿挑戰，對患者術後也有一些併發症，但從聽力改善程度來看，約71％的患者從中度、中重度重聽變成輕度重聽或更好。因此只要條件夠，有明顯的氣導骨導差（air-bone gap）和乳突氣化良好，手術是應考慮的。

關鍵字

先天性閉鎖 ； 耳道成形術 ； 膽脂瘤

並列摘要

BACKGROUND: Congenital aural atresia and stenosis often result from anomalies of the middle ear structures and facial nerve. Surgical intervention to reestablish sound perception is a challenge in these kinds of cases.
METHODS: Recently, We have performed thirty six otologic surgeries on congenital anomalies of the external auditory canal. Five of the patients suffered from cholesteatoma with complications and the purpose of these operations was to eliminate the infection. Amongst these patients, one received canalplasty, three mastoidectomies, and one canal obliteration. The remaining 31 ears from 29 patients had surgery performed on them to improve their hearing.
RESULTS: The patients who had surgery to improve hearing were aged from 4 years to 32 years, with a median age of 11. Two cases of ear surgery were lost during follow-up. Four ears did not show any change in their audiogram. Twenty-five ears showed an improvement in hearing, from an average hearing threshold of 61.7dB preoperatively to 33.5dB postoperatively. Twelve ears displayed conductive hearing over the range 26dB and 40dB, and ten ears showed an even better conductive hearing at below 25dB. Approximately 71% of the patients had an outcome of better hearing after the operation was performed. In general, there was very little change to bone conductive hearing, but four ears became worse at 4KHz. In all four cases, there were anomalies of the ossicles, including attachment of malleus lateral process and atretic plate, shortening of malleus handle, malleus-incus joint fixation, thinning of long process of incus, stapes malformation, and fixation of foot plate. Post operative complications were external ear canal stricture from scarring, Granulation in the canal, lateralization of the ear drum, cerumen impaction, and abnormal osteogenesis of the canal.
CONCLUSION: Surgery of congenital anomalies of external ear canal is a challenging operation and does give rise to some risk of complications. However, from the results presented here, 71%of patients had a better hearing after the operation and therefore surgical intervention is a worthwhile appropriate approach.

並列關鍵字

congential atresia ； canalplasty ； cholesteatoma