A patient’s natural hearing is often lost after cochlear implantation, reducing the quality of their listening experience. We plan to unravel the cause of this hearing loss, which occurs in the months after cochlear implantation by using a novel imaging technique developed by the investigators: whole cochlear imaging. This imaging technique involves shining laser lights through the whole cochlea, which has been made transparent and labelled with antibodies, enabling a holistic investigation of most parts of the hearing system at once, with the cochlear implant left in place.
We will determine whether natural hearing is lost because of inner-ear scarring or alternatively, burn-out of the connection between the cochlea’s sensory cells and nerves. This will be achieved by giving experimental animals cochlear implants, monitoring their natural hearing, and then relating the hearing loss to changes within the cochlea seen on whole cochlear imaging. We will also explore how a drug that can be delivered by a cochlear implant, the steroid dexamethasone, reduces inner-ear scarring and whether it can prevent nerve burn-out. The work will guide efforts to prevent the loss of natural hearing.