Biomaterial Database

Tympanic membrane retraction and middle-ear pressure. 1982

H R Cable, and S Tadros

MHA assessment and LR observation are poor indicators of MEP. Clinical assessment of the MHA in normal living ears, within the range 30 degrees to 75 degrees, correlates poorly with MEP measured by impedance tympanometry, within the range of -300 to +160 mm H2O. Variation of MEP in fresh temporal bones demonstrated that MHA, LR and postero-superior segment retraction remained unchanged between -50 and -400 mm H2O and between +50 and +400 mm H2O. The change in position of the TM over the range +50 to -50 mm H2O corresponded to the maximum compliance change on the tympanogram i.e. the width of the tympanometric notch.

UI	MeSH Term	Description	Entries
D008307	Malleus	The largest of the auditory ossicles, and the one attached to the membrana tympani (TYMPANIC MEMBRANE). Its club-shaped head articulates with the INCUS.
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
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
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
D014432	Tympanic Membrane	An oval semitransparent membrane separating the external EAR CANAL from the tympanic cavity (EAR, MIDDLE). It contains three layers: the skin of the external ear canal; the core of radially and circularly arranged collagen fibers; and the MUCOSA of the middle ear.	Eardrum,Eardrums,Membrane, Tympanic,Membranes, Tympanic,Tympanic Membranes