023 Effect of malleus handle fracture on middle ear sound transmission: Laser Doppler vibrometry measurements and finite element simulations

Malleus handle fractures are rare but can cause tremendous hearing loss. Due to the small number of known clinical malleus fracture cases, little is known about the mechanics of middle ears with a malleus fracture. Laser Doppler vibrometry and finite element simulations are used to gain more knowledge about malleus fractures. The experimental measurements show remarkably that at low frequencies an increase in sound transmission can occur and minimal hearing loss occurs below the intact middle ear resonance frequency due to a resonance shift. The simulations do not show these observations when only a fracture is introduced. The addition of other features possibly related to malleus fractures to the models such as the post-fracture eardrum prestress release improve the simulation results. However, features such as post-fracture eardrum deformation could play an important role too.