A Finite Element Analysis of a Healthy Middle-Ear and a Middle-Ear Reconstructed With Prostheses

Abstract The human car is a complex biomechanical arrangement of bones and soft-tissues. To sense a sound, the pressure wave enters the ear canal (a curved tube) and is transformed as it travels towards the tympanic membrane (or ear drum). The tympanic membrane vibrates causing motion of the three bones of the middle-ear: the malleus, incus, and stapes (commonly called the hammer, anvil, and stirrup). The stapes motion stimulates the perilymph fluid of the inner-ear leading to an electrical pulse to the brain allowing us to perceive sounds. The there bones (called the ossicles) are suspended from the surrounding bone by various ligaments. Replacement of the ossicles with a prosthesis is a common surgical procedure, though it is not entirely satisfactory because the prosthesis can loosen or even extrude out from the middle-ear. In this study, we have developed an FE model of the healthy middle-ear and compared its vibro-acoustic response with the middle-ear reconstructed with two types of prosthesis — a partial ossicular replacement prosthesis (PORP) and a total ossicular replacement prosthesis (TORP).