Click evoked otoacoustic emissions (CEOEs) from the human ear were first reported by Kemp in 1978. The CEOEs is a release of audiofrequency energy into the external ear canal from the cochlea transmitted through the ossicular chain and the tympanum. Otoacoustic emission is now a routine audiologic procedures. As an objective, easy, rapid and noninvasive audiologic procedure, the click evoked otoacoustic emission recording is considered a useful screening technique for neonates. The CEOEs were recorded from 73 ears of 42 full term newborns, ranging in age from 9 hours to 18 days after birth. They were normal in development and health status. All the tested ears showed positive CEOEs, but 6 ears required a repeat of the test because of negative results in the initial test. The mean threshold of click stimulus was 68.1dB peak SPL(-11.4dB Test gain) and the peak frequency in echo response was 2.5kHz(1-4kHz range) in average.
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