健康新生兒之歪成份耳聲傳射

Distortion Product Otoacoustic Emission in Healthy Newborns

我們對30名（60耳）健康的新生兒進行歪成份耳聲傳射檢查，以建立正常值分佈資料。他們的平均耳聲傳射圖顯示在高頻部份(fl>1000 Hz)與正常成年人相似，皆呈中間凹陷之雙高原型，峰值在f1=1593 Hz和4000 Hz處。低頻部份(fl<1000 Hz)的背景嗓音則相當高，甚至超越該頻率之歪成份耳聲傳射，顯示在研究新生兒的低頻聽力時（約為耳蝸基底膜上相對應頻率小於1 kHz的部份），歪成份耳聲傳射仍有相當大的限制。

Distortion product otoacoustic emission (DPOAE) can be used as a screening technique for hearing in newborns, and may also provide frequency-specific information about the functional state of the cochlea. We recorded DPOAEs of 30 healthy newborns to establish the distortion product-gram (DP-gram) in this population. The fl/f2 ratio was fixed at 1.2 and the stimulus intensity was 70 dB SPL (L1=L2). The DP-grams were quite similar to those observed in adults, with two sharp peaks of maximum amplitude at fl frequencies of 1593 Hz and 4000 Hz, and a decline in DPOAE in mid-frequencies. The background noise was very high at low frequencies (fl