The patient is admitted to one of the participating clinical centers because of a brain tumor, which requires surgery to be removed. As discussed in detail with the treating surgeon, the tumor is large, and an approach will be used that accesses the tumor from the side through the temporal bone. This approach passes by the balance and hearing organ, and the partial or complete removal of the organ responsible for balance and hearing on this side is necessary. Participation in the study will extend the time of surgery by 30 minutes. There is no special preparation and no follow-up required for the study.
In this study, a cochlear implant system that uses light to stimulate the cochlea will be tested. It is a small light delivery system consisting of optical fibers and light sources the size of a human hair. This light delivery system will be inserted into the hearing organ, the cochlea before it is damaged or removed during the tumor surgery. After insertion into the cochlea, pulses of infrared light will be delivered to the cochlea, and auditory responses will be measured with a small electrode placed at the cochlea.
If possible, after completion of the measurements and during the continuation of the tumor surgery, the tissue of the hearing organ, which is typically destroyed through the drilling, will be harvested for histological evaluation.