Biomaterial Database

Distortion product otoacoustic emissions. The influence of the middle ear transmission. 1993

P A Osterhammel, and L H Nielsen, and A N Rasmussen

Department of Otolaryngology, Head and Neck Surgery, University Hospital, Copenhagen, Denmark.

Distortion product otoacoustic emissions (DPOEs) were recorded in 8 normal hearing subjects (16 ears, mean age 37) in order to evaluate the sensitivity of the DPOE amplitudes as a function of pneumatic changes (-400 to +200 daPa) in the external ear canal. The responses were collected using time averaging and subsequent FFT-analysis of the collected data. Distortion products were measured at the following geometric mean frequencies: 1,000, 2,000, 4,000, 6,000 and 8,000 Hz. The results show that the amplitudes of the distortion products depend on an optimal transmission through the middle ear, and that measurements of DPOEs should always be preceded by determination of the middle ear pressure. The present findings are in good agreement with investigations based on evoked otoacoustic emissions published by other researchers.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D012022	Reflex, Acoustic	Intra-aural contraction of tensor tympani and stapedius in response to sound.	Acoustic Reflex
D003051	Cochlea	The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.	Cochleas
D004424	Ear Canal	The narrow passage way that conducts the sound collected by the EAR AURICLE to the TYMPANIC MEMBRANE.	Auditory Canal, External,External Acoustic Canal,External Acoustic Meatus,External Auditory Canal,External Ear Canal,Acoustic Canal, External,Acoustic Canals, External,Acoustic Meatus, External,Auditory Canals, External,Canal, Ear,Canal, External Ear,Canals, Ear,Canals, External Ear,Ear Canal, External,Ear Canals,Ear Canals, External,External Acoustic Canals,External Auditory Canals,External Ear Canals
D004432	Ear, Middle	The space and structures directly internal to the TYMPANIC MEMBRANE and external to the inner ear (LABYRINTH). Its major components include the AUDITORY OSSICLES and the EUSTACHIAN TUBE that connects the cavity of middle ear (tympanic cavity) to the upper part of the throat.	Tympanic Cavity,Tympanum,Middle Ear,Cavities, Tympanic,Cavity, Tympanic,Ears, Middle,Middle Ears,Tympanic Cavities,Tympanums
D005260	Female		Females
D006309	Hearing	The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.	Audition
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000158	Acoustic Impedance Tests	Objective tests of middle ear function based on the difficulty (impedance) or ease (admittance) of sound flow through the middle ear. These include static impedance and dynamic impedance (i.e., tympanometry and impedance tests in conjunction with intra-aural muscle reflex elicitation). This term is used also for various components of impedance and admittance (e.g., compliance, conductance, reactance, resistance, susceptance).	Audiometry, Impedance,Electroacoustic Impedance Tests,Impedance Tests, Acoustic,Tympanometry,Acoustic Impedance Test,Electroacoustic Impedance Test,Impedance Audiometry,Impedance Test, Acoustic,Impedance Test, Electroacoustic,Impedance Tests, Electroacoustic,Test, Acoustic Impedance,Test, Electroacoustic Impedance,Tests, Acoustic Impedance,Tests, Electroacoustic Impedance