Isolated Congenital Incus Anomaly: Report of a Case

單獨發生的先天性砧骨異常：病例報告

鄭富城(Fuh-Cherng Jeng) ； 姚程豐(Cheng-Feng Yao) ； 蔡銘修(Ming-Hsui Tsai)

《Mid-Taiwan Journal of Medicine》 6卷4期 (2001/12) Pp. 244-248

https://doi.org/10.6558/MTJM.2001.6(4).8

摘要

綜觀國內外文獻，先天性聽小骨異常並不多見，而單獨發生於砧骨的先天性異常更為罕見。先天性砧骨異常常伴隨有外耳的異常，臨床上的表現為傳音性聽力受損，在沒有合併外耳異常的情況下常被忽略，確定診斷需仰賴鼓室探查術。本院於2000年6月間經歷-主訴右耳聽力受損多年之13歲女性病例，理學檢查發現耳殼及外耳道正常，耳鏡檢查發現耳膜無下陷、紅腫等異常情形，聽力檢查呈現右耳42分貝傳音性聽力受損，氣骨導間距為33分貝，鼓室圖呈現A型。患者於2000年7月接受右耳鼓室探查術，術中發現耐骨呈短小棒狀與鐙骨相連，鐙骨活動良好但與槌骨各自分離，此外並無肉芽組織、中耳積液或其他可見之中耳病變。在移除異常之砧骨後，將部份人工聽小骨(Xomed 11-56362)置於鐙骨之上，並放置一片薄的耳珠軟骨於耳膜與人工聽小骨之間。術後6個月追蹤聽力情況，氣導閾值為22分貝，氣骨導間距為18分貝。氣導閾值較術前進步20分貝，氣骨導間距進步15分貝。因屬罕見病例，特此提出報告。

關鍵字

傳音性聽力受損,先天性聽小骨異常,鼓室探查術,聽小骨成型術

並列摘要

Congenital ossicular anomalies are often encountered in patients with congenital aural atresia and less frequently in patients with normal external ears. The most common site of isolated congenital ossicular anomalies is the stapes. Isolated congenital incus anomalies are rare. In June 2000, a thirteen-year-old girl visited our department complaining of hearing loss in the right ear since childhood. The external ears were normal. The pure tone audiometry showed 42 dB hearing loss with a 33 dB air-bone gap in the right ear. As the tympanic membrane was elevated during exploratory tympanotomy, the incus was found to be anomalous and resembled a small bar with one end attached to the head of the stapes while the other end was free. Both the malleus and the stapes were normal and mobile. We placed a piece of partial ossicular replacement prosthesis (Xomed 11-56362) onto the head of the stapes. We also inserted a piece of tragal cartilage between the eardrum and the prosthesis in order to prevent early protrusion of the prosthesis. The postoperative hearing gain was 15dB, and there has been no evidence of hearing deterioration over the last 12 months of follow-up.

並列關鍵字

conductive hearing loss,congenital ossicular anomaly,exploratory tympanotomy,ossiculoplasty