Investigation of cochlear disturbance induced during surgical intervention

Abstract

Hearing loss is a common impairment or disability for human beings, and is impacting an increasing amount of people, augmented by the growing aging population around the globe. Cochlear implantation, as one of the most effective ways to restore hearing, can only applied to profoundly deaf patients at the moment. In order to expand the group of people who can benefit from cochlear implantation to those with less severe hearing loss, endeavours need to be made to best preserve residual hearing and minimise trauma induced during cochlear implantation surgery. In this thesis, the disturbance induced in the cochlea, i.e. the acoustic and mechanical energy transmitted into the cochlea, during cochleostomy drilling is studied – as well as establishing a comparison between a manually guided conventional technique and a manually supported tissue guided robotic drilling technique. The results show that by changing surgical techniques and how they are applied can have a significant impact on levels of disturbance induced – robotic-aided approach induced lower level of equivalent SPL for up to 86% of the time and can be as much as 39 dB lower than that generated by conventional surgical drilling. This work is timely because trauma is an important consideration to clinicians and health care providers. Cochleostomy is one of the major and most disruptive surgical process during cochlear implantation. With the increasing amount of cochlear implant electrode array designs that are shorter and less intrusive, and the increasing demand of electric-acoustic stimulation via cochlear implant to better resemble the human auditory system, the approach to reduce disruption during cochleostomy drilling is highly relevant to the progression in the hearing care industry and the benefits of the growing hearing impairment community.