The relationship between round window and ear canal Cochlear microphonic

Abstract

Hypothesis: Cochlear microphonic recorded at ear canal (CM-EC) can be a substitute for the one recorded at round window (CM-RW).Background: Almost all clinics do not measure tone-burst evoked CM due to technical difficulty although it can provide more information than click evoked CM. Moreover, clinicians like the CM-EC more than that measured at CM-RW because CM-EC is non-invasive. There is difference between CM-RW and CM-EC, for example, CM-EC is less prominent than CM-RW, therefore, studying tone-burst evoked CM-EC and its relationship with CM-RW are highly significant and can promote the clinical application of CM-EC.Method: Nine guinea pigs were randomly allocated into three groups, group 1 was not exposed to noise, called normal control. group 2 and group 3 were exposed to the low-(0.5-2 kHz) and high-frequency band-noise (6-8 kHz) at 120 dB SPL for 1 h, respectively. It was difficulty to record low-frequency CM due to severe environmental interruption, in current study the recording technology of tone-burst evoked CM