Analysis of the effect of different patologies on the sound transmission through the middle ear by means of a finite-element model

Abstract

The middle ear is part of the human auditory system and its function is to transmit acoustical energy to the inner ear by means of mechanical vibrations. Finite-Element (FE) models of the human middle ear have been studied since 90s, making it possible to evaluate its dynamic behavior in different ways. In this work, an accurate FE model of the human middle ear is described and used for assessing the relationship between the reduction of sound transmission through the ossicular chain and hearing loss due to three different pathologies: tympanic membrane perforation, stapedial tendon ossification and stapes fracture. For these three pathologies, case studies from the literature with experimental hearing loss data are reviewed and clinical results are compared to the FE model predictions. In all cases a good relationship between sound transmission reduction predicted by the FE model and the hearing loss measured through audiometric tests were found. Results show that an accurate FE model of the human middle ear can be a powerful tool for clinical applications and research in otology, allowing to predict the effect of middle ear pathologies and to evaluate the results of corrective surgeries on hearing.