title: Contralateral ear occlusion for improving the reliability of otoacoustic emission screening tests.
abstract: Newborn hearing screening is an established healthcare standard in many countries and testing is feasible using otoacoustic emission (OAE) recording. It is well documented that OAEs can be suppressed by acoustic stimulation of the ear contralateral to the test ear. In clinical otoacoustic emission testing carried out in a sound attenuating booth, ambient noise levels are low such that the efferent system is not activated. However in newborn hearing screening, OAEs are often recorded in hospital or clinic environments, where ambient noise levels can be 60-70 dB SPL. Thus, results in the test ear can be influenced by ambient noise stimulating the opposite ear. Surprisingly, in hearing screening protocols there are no recommendations for avoiding contralateral suppression, that is, protecting the opposite ear from noise by blocking the ear canal. In the present study we have compared transient evoked and distortion product OAEs measured with and without contralateral ear plugging, in environmental settings with ambient noise levels <25 dB SPL, 45 dB SPL, and 55 dB SPL. We found out that without contralateral ear occlusion, ambient noise levels above 55 dB SPL can significantly attenuate OAE signals. We strongly suggest contralateral ear occlusion in OAE based hearing screening in noisy environments.
authors.affiliation: Auditory Science Laboratory, Neuroscience and Mental Health Program, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada M5G 1X8.
authors.forename: Emily
authors.initials: E
authors.lastname: Papsin
authors.affiliation: Auditory Science Laboratory, Neuroscience and Mental Health Program, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada M5G 1X8.
authors.forename: Adrienne L
authors.initials: AL
authors.lastname: Harrison
authors.affiliation: Auditory Science Laboratory, Neuroscience and Mental Health Program, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada M5G 1X8 ; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 1A1.
authors.forename: Mattia
authors.identifier: 0000-0002-2439-9904
authors.initials: M
authors.lastname: Carraro
authors.affiliation: Auditory Science Laboratory, Neuroscience and Mental Health Program, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada M5G 1X8 ; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 1A1 ; Department of Otolaryngology-Head and Neck Surgery, University of Toronto, 190 Elizabeth Street, Toronto, ON, Canada M5G 2N2.
authors.forename: Robert V
authors.initials: RV
authors.lastname: Harrison