The Natural Vibration Characteristics of Human Ossicles

Background: Recently, a model of the ossicular chain for finite element analysis has beendeveloped. However, the natural vibration characteristics of human ossicleshave never been studied. Herein, we investigated the dynamic characteristicsof the coupling of in-vivo ossicles using finite element analysis.Methods: The geometry of the ossicular chain was obtained by high-resolution computedtomography of the temporal bone, and a 3D model of the ossicularchain was reconstructed by the medical imaging software, Amira . The filewas then imported into the finite element analysis software, ANSYS . Thenatural vibration characteristics of human ossicles were measured by finiteelement analysis.Results: The characteristic dimensions of the model were measured and comparedwith previously published data. The malleus resonated to sound stimuli at 3kHz and 4 kHz; the incus and stapes did not resonate to sound stimuli at anyfrequency. A coupling of the incus and malleus easily resonated to soundstimuli at 5 kHz. A coupling of the incus and stapes easily resonated tosound stimuli at 3 kHz. The coupling of the ossicular chain easily resonatedto sound stimuli at 5 kHz, 6 kHz and 8 kHz.Conclusion: The dynamic characteristics of the ossicular chain were analyzed by finiteelement analysis method. The characteristics of a free vibration model of theossicles could be determined, which would be helpful in evaluation and consultationfor ossicular prosthesis development.