Concept, design and evaluation of a novel electrical auditory prosthesis for direct stimulation within the auditory nerve: the Auditory Nerve Implant (ANI).

Introduction In collaboration with several institutes and medical device companies, we are currently developing an intracranial electrical auditory prosthesis that stimulates directly within the auditory nerve: the Auditory Nerve Implant (ANI). Surgical techniques and the implant design will be evaluated in human preparations and intraoperative experiments. In addition, auditory brainstem responses will be verified by stimulating the human auditory nerve.

Materials & Methods In an iterative process between cadaver and intraoperative acute experiments, different approaches, array anchoring, insertion, and implant design were tested and verified. In patients who were undergoing acoustic neuroma removal, a surface electrode was placed on the auditory nerve, electrically stimulated, and derived from the scull surface.

Results The translabyrinthine approach was shown to be the most appropriate. Intraoperatively, auditory brainstem responses could be electrically derived in 2 patients without producing co-stimulation of the facial nerve. Selective electrical stimulation is thus possible. It should be noted that due to the tumors and their removal, the auditory nerves were already severely compromised in their functional integrity.

Discussion The ANI can potentially represent an alternative to the CI for patients in whom a CI is not possible but having a functional auditory nerve. In addition to the stimulation on the surface of the auditory nerve, the next step will be an acute stimulation with the penetrating electrode array. However, due to the new directive, Medical Device Regulation, the development of new medical devices is associated with considerable costs and time.

NIH UG3NS107688

Publication History

Article published online:
12 May 2023