title: Contralateral suppression of transient evoked otoacoustic emissions: normative data for a clinical test set-up.
abstract: OBJECTIVE
  Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) can be used in a clinical set-up using a procedure based on a unique and robust parameter to quantify the magnitude of suppression for a subject.
  
  
  BACKGROUND
  TEOAEs can be suppressed by delivering contralateral white noise (WN). This suppression is thought to be mediated via the efferent nerve fibers that innervate the outer hair cells. The ipsilateral TEOAE-eliciting click stimulus level and the contralateral WN level have a strong impact on the recorded level of suppression.
  
  
  METHODS
  TEOAEs were recorded using the nonlinear stimulation mode in two conditions (with and without contralateral WN). An optimal TEOAE-eliciting click stimulus level and contralateral WN level were defined to obtain a unique and robust parameter to quantify the magnitude of suppression.
  
  
  RESULTS
  Suppression of TEOAEs with contralateral WN can be measured in a clinical set-up using nonlinear stimulation, and the level of suppression is of the same order of magnitude as measures using the linear stimulation recording mode. The level of suppression appears to be "locked" to the interaural difference between ipsilateral TEOAE-eliciting broadband click stimulus level and the contralateral WN level.
  
  
  CONCLUSIONS
  A procedure is proposed to record contralateral suppression in a clinical set-up, and normative data are given for a normal-hearing population (n = 60).
authors.affiliation: University Department of Otolaryngology, St. Augustinus Hospital, Antwerp-Wilrijk, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: De Ceulaer
authors.forename: M
authors.initials: M
authors.lastname: Yperman
authors.forename: K
authors.initials: K
authors.lastname: Daemers
authors.forename: K
authors.initials: K
authors.lastname: Van Driessche
authors.forename: T
authors.initials: T
authors.lastname: Somers
authors.forename: F E
authors.initials: FE
authors.lastname: Offeciers
authors.forename: P J
authors.initials: PJ
authors.lastname: Govaerts
mesh_terms: D000293:Adolescent; D000328:Adult; D001309:Auditory Threshold / Q000502:physiology; D001696:Biomechanical Phenomena; D002648:Child; D003051:Cochlea / Q000502:physiology; D005260:Female; D018072:Hair Cells, Auditory, Outer / Q000502:physiology; D006320:Hearing Tests / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D012016:Reference Values