Abstract (EN):
The auditory system consists of the external ear, Middle Ear (ME) and inner ear. The ME consists of the ossicular chain (malleus, incus and stapes), ligaments, muscles and tendons. The sound energy perceived by the ear passes through the external auditory canal to the Tympanic Membrane (TM), where it is transformed into mechanical energy being transmitted to the ossicles. The objective of this study is to analyze the fibers directions effects of central layer of the TM in the dynamic analysis of the human ME. A digital model was constructed based on images extracted from Computed Tomography (CT). The discretization of the model was based on the Finite Element Method (FEM), using the ABAQUS software. The material properties were based on previous work. Distinct properties for each layer of the TM were considered, since they have different performance. The central layer was considered orthotropic (because of the concentration of fibers) while the others two were considered isotropic. The simulation was conducted focusing on the TM sound pressure level of 130 dB SPL, since this is the highest level of intensity of a sound wave that the human ear can perceive and interpret. The results were compared in the dynamic analysis of the ME for a frequency range of 100 Hz to 10 kHz. This led to the displacement of the four quadrants of the pars tensa of the TM. Varying only the predominance of the circular fibers, it is possible to verify the differences of the movements of the TM.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
5