| Otoacoustic Emissions (OAEs) are sounds generated by an active process in the auditory system's cochlea. It has been widely accepted that the generation of OAEs is a precursor for healthy hearing. The measurement of evoked OAEs can be used to determine the general health of the cochlea and basilar membrane's response and sound transmission forward and backwards through the inner ear. OAEs are commonly used for newborn infant hearing screening where many middle ear pathologies are first detected. In most cases, secondary screening tests such as tympanometry are not conducted unless the patient has failed the OAE screening first. Increases in ear canal pressure have an almost identical effect on OAE recordings when compared to naturally occurring negative middle ear pressures (NMEPs) (Sun & Shaver, 2009). Thus arises the need for pressure compensated OAE screening. This study aims at reviewing the design of a self-compensating pressure system capable of generating steady meatal pressures during OAE subject screening. Facets of system design including patient safety, software interaction, and initial test results will be presented. We will also present the results of a volunteer study which collected the TEOAE and meatal responses of 20 individual ears during multiple pressure criteria. Testing and analysis of signals in both the time and frequency domains will be reviewed. |
