Abstract
The ossicular chain, which consists of the malleus, the incus and the stapes, plays an important role in auditory mechanics. If the ossicles become fixed somewhere, hearing loss occurs. In order to improve the level of hearing, the fixed part of the ossicles must be replaced. It is important to evaluate the mobility of the stapes during the tympanoplasty surgery, because the ossicular mobility affects the prognosis for the improvement of the hearing level. However, an objective measurement of the stapes mobility has up to now been rarely performed during a surgery. In a previous study, we created a mechanism which consists of a force sensor and an actuator and pushes the ossicles during surgery. Then we evaluated the ossicular mobility based on the relationship between the force and the displacement. In this study, we propose a new mechanism. The probe of the measuring system consists of an ear-pick, an actuator with a strain gauge and a force sensor. We vibrate the ossicles with the ear-pick and measure the reaction force and displacement of the ossicles with the force sensor and the strain gauge. From the relationship between the reaction force and the displacement, the degree of the fixation of the ossicles is quantitatively evaluated.
