[An electromechanical model of the middle ear].
A dynamic model of the middle ear and mastoid system was designed in order to evaluate basic principles in tympanometry. The model allows controlled simulation of the exact changes in the ear drum's mass and in intratympanic volume and pressure. The contribution of each of these factors to acoustic impedance was measured. We found that the volume values of static, acoustic compliance were equal to the volume of air in a closed cell. There was good correlation between direct measurement of air pressure in the model cell and indirect pressure measurement by tympanometry. We also demonstrated a difference between mechanical displacement of the drum and its displacement by negative pressure. This demonstration of tympanometry using a middle-ear compatible model enables us to understand its principles and helps in the education of students.
Danino
J
J
ENT Dept., Rambam Medical Center, Haifa.
Nir
D
D
Golz
A
A
Joachims
H Z
HZ
D000158:Acoustic Impedance Tests; D004432:Ear, Middle; D006801:Humans; D008961:Models, Structural