耳聲傳射之臨床應用

Clinical Application of Otoacoustic Emissions

林鴻清(Hung-Ching Lin) ； 徐銘燦(Min-Tsan Shu) ； 張克昌(Ke-Chang Chang)

《聽語會刊》 13期 (1998/06) Pp. 14-23

https://doi.org/10.6143/JSLHAT.1998.06.02

摘要

耳聲傳射(OAEs)係耳蝸(Cochlea)釋放的能量，經由中耳傳送至外耳。而內耳柯氏器(Organ of Corti)內有一放大機制；負責耳聲傳射之產生。據信外毛細胞(Outer hair cells)係負責此一放大機制。因此耳聲傳射係可以由外耳偵測內耳外毛細胞之功能。另外耳聲傳射具有頻率專一性(frequency specific)及頻率選擇性(frequency selective)。即言之，耳聲傳射之產生即表示外毛細胞(OHCs)之功能正常；且能量傳送出外耳之途徑也尚良好。且不同的耳聲傳射頻率可以顯現不同耳蝸部位之功能。短暫誘發耳聲傳射(transient evoked otoacoustic emissions)係以短暫刺激(如：click, tone burst)予以誘發。它幾乎百分之百存在於正常聽力耳。約25-30分貝之感音神經聽力損失，即會令它消失。當然這必須同時考慮中耳之狀況，據信約25-30分貝之氣導骨導間距(Air-Bone gap)時，也會令它消失。其主要之臨床應用有：一、用於嬰幼兒之聽力篩檢，二、鑑識詐聾者(Malinger)。三、鑑別耳蝸及耳蝸後的聽力損失，四、偵測耳毒性藥物及噪音對耳蝸的傷害。

並列摘要

Otoacoustic emissions are a release of vibrational energy at audiofrequency into the ear canal form the cochlea, transmitted through the ossicular chain and tympanum. It has been proposed that a biomechanical amplifier within the organ of Corti underlies OAEs. It is also believed that the outer hair cells are most likely to effect this amplification process. Thus, otoacoustic emissions can offer a method of probing certain functional aspects of the cochlea from the canal. Moreover, otoacoustic emissions are frequency specific and selective. In other word, the presence of OAEs indicates the function of OHCs is normal and the transmission of energy from the cochlea to the canal is satisfactory. Different OAE frequencies may give information about functional status at different parts of cochlea. Transient evoked otoacoustic emissions is stimulared by click or tone burst. It is present nearly in all normal hearing ears﹒The presence of TEOAEs indicates peripheral hearing sensitivity of 25 to 30 dB HL or better. However, the condition of middle ear must be evaluated simultaneously. It is believed that TEOAEs will be attenuated when Air-bone gap is larger then 25-30 dB. The clinical application of otoacoustic emissions arc as follows:(1). Infant hearing screening (2). To assess malinger (3). To assess cochlear and retrocochlear hearing loss (4). To probe cochlear damage due to noise and ototoxic drugs.