Prosthetic Implantation of the Human Vestibular System

Abstract

Hypothesis A functional vestibular prosthesis can be implanted in human such that electrical stimulation of each semicircular canal produces canal-specific eye movements while preserving vestibular and auditory function. Background A number of vestibular disorders could be treated with prosthetic stimulation of the vestibular end organs. We have previously demonstrated in rhesus monkeys that a vestibular neurostimulator, based on the Nucleus Freedom cochlear implant, can produce canal-specific electrically evoked eye movements while preserving auditory and vestibular function. An investigational device exemption has been obtained from the FDA to study the feasibility of treating uncontrolled Ménière’s disease with the device. Methods The UW/Nucleus vestibular implant was implanted in the perilymphatic space adjacent to the three semicircular canal ampullae of a human subject with uncontrolled Ménière’s disease. Pre and postoperative vestibular and auditory function were assessed. Electrically evoked eye movements were measured at two time points postoperatively. Results Implantation of all semicircular canals was technically feasible. Horizontal canal and auditory function were largely, but not totally, lost. Electrode stimulation in two of three canals resulted in canal-appropriate eye movements. Over time, stimulation thresholds increased. Conclusions Prosthetic implantation of the semicircular canals in humans is technically feasible. Electrical stimulation resulted in canal-specific eye movements, although thresholds increased over time. Preservation of native auditory and vestibular function, previously observed in animals, was not demonstrated in a single subject with advanced Ménière’s disease.

Characterization of pulse amplitude and pulse rate modulation for a human vestibular implant during acute electrical stimulation

“…Identifying the more effective modulation paradigm has become increasingly relevant, as the concept of using modified cochlear implants has shown promise (Guyot et al 2011a(Guyot et al , 2011b and is being adopted also by other groups (Valentin et al 2013, Golub et al 2014, Phillips et al 2015. Cochlear implants use PAM per default for speech encoding.…”

“…A systematic comparison of PAM and PRM has recently become increasingly necessary and urgent with the more widespread adoption of modified cochlear implants for vestibular stimulation (Valentin et al 2013, Golub et al 2014, Guinand et al 2015. The study herein is the first systematic comparison of both modulation paradigms in patients.…”

“…Our group further demonstrated with PAM single-axis VOR restoration (Perez Fornos et al 2014) and VOR dependency on modulation frequency (Van De Berg et al 2015b). A second group also performed VI instrumentation in patients (Golub et al 2014). They then recorded eye movement responses to different pulse amplitudes and pulse rates at regular intervals over the course of a year or longer.…”

Bilateral Vestibular Hypofunction: Challenges in Establishing the Diagnosis in Adults

“…Once established, BVH could be classified according to severity, taking not only objective measures but also functional impairment into account. A classification according to severity could be important, since much progress has been made in developing a vestibular implant [144,166,167,168] and such a classification could facilitate patient selection. If necessary, a subdivision into probability groups (e.g.…”

Vestibular Implants: 8 Years of Experience with Electrical Stimulation of the Vestibular Nerve in 11 Patients with Bilateral Vestibular Loss

“…In humans, extralabyrinthine and intralabyrinthine surgical routes to the lateral (LAN), posterior (PAN) and superior (SAN) ampullary branches of the vestibular nerve have been described and validated in peroperative stimulation trials [38,39,40,41,42,43]. Our group has reported on the results of the first chronic implantations of a vestibular implant prototype in human subjects [44], followed by a group at the University of Washington [45]. Our most recent results demonstrated that it is possible to elicit an artificial, motion-controlled vestibulo-ocular reflex in implanted patients [46].…”