Opto-electrical Cochlear Implants

NCT05110183 | Enrolling By Invitation FDA Device

• 2 other identifiers: STU00209027R01DC018666
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 2

Brief Summary

Neural stimulation with photons has been proposed for a next generation of cochlear implants (CIs). The potential benefit of photonic over electrical stimulation is its spatially selective activation of small populations of spiral ganglion neurons (SGNs). Stimulating smaller neuron populations along the cochlea provides a larger number of independent channels to encode acoustic information. Hearing could therefore be restored at a higher fidelity and performance in noisy listening environments as well as music appreciation are likely to improve . While it has been demonstrated that optical radiation evokes auditory responses in animal models, it is not clear whether the radiant exposures used in the animal experiments are sufficient to stimulate the auditory system of humans. The proposed tests are:

1. 1.to demonstrate that light delivery systems (LDSs) can be inserted and oriented optimally in the human cochlea.
2. 2.to show that the LDSs are able to deliver sufficient amount of energy to evoke a compound action potential of the auditory nerve.
3. 3.to validate that the fluence rate (energy / target area) required for stimulation is below the maximal fluence rate, which damaged the cochlea in animal experiments.
4. 4.to show that combined optical and electrical stimulation is able to significantly lower the threshold required for optical stimulation in humans.

Conditions

Hearing Loss

Keywords

deaf; neural stimulation with light; cochlear implant

Outcome Measures

Primary Outcomes (1)

• Compound Action Potential (CAP)

  Compound action potentials (CAPs) of the auditory nerve in response to electrical stimulation, optical stimulation, and combined optical and electrical stimulation will be recorded. Electrical stimulation alone is used to determine baseline cochlear function. Optical stimulation alone will then be used to determine a similar baseline for optical stimulation and test parameters such as optical pulse rate, pulse duration and radiant exposure.

  30 minutes

Study Arms (1)

electrical and optical hybrid stimulation stimulation

EXPERIMENTAL

Patients with large tumors of the skull base, requiring a translabyrinthine craniotomy with sacrifice of their cochlea and vestibular system during the tumor resection may participate. A recording electrode will be placed on the round window, a cochleostomy will be created, and different Light delivery systems (LDSs) will be inserted into the cochlea. LDSs include angle polished optical fibers to determine the accuracy of the orientation of the radiation beam, and hybrid arrays of small optical sources and electrical contacts to evaluate electric-alone stimulation as a reference, and compare it to optic-alone and combined electrical and optical stimulation. Compound action potentials (CAPs) of the auditory nerve will be recorded.

Device: electrical stimulation; Other: optical stimulation; Other: combined optical and electrical stimulation

Interventions

electrical stimulation DEVICE

A cochlear implant electrode will be inserted through a cochleostomy into scala tympani of the cochlear basal turn. Custom software on a laptop computer will be used to control the delivery of a sequence of charge balanced current pules.

electrical and optical hybrid stimulation stimulation

optical stimulation OTHER

Optical fibers will be inserted through a cochleostomy into scala tympani of the cochlear basal turn. Custom software will be used to control the delivery of a sequence of charge balanced current pules.

electrical and optical hybrid stimulation stimulation

combined optical and electrical stimulation OTHER

A short hybrid array consisting of optical sources and electrical contacts will be inserted through a cochleostomy into scala tympani of the cochlear basal turn. Biphasic electrical current pulse and optical pulse delivery will be controlled in amplitude and timing by a computer.

electrical and optical hybrid stimulation stimulation

Eligibility Criteria

• Age: 18 Years - 89 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• the tumor grows in the pontine angle and the facial nerve is at risk for damage during the surgery because the tumor is already large and in close proximity of the facial nerve AND
• the tumor is larger than 2.5 cm AND
• Pure tone hearing thresholds are elevated by at least 50 dB AND
• Speech discrimination scores are 50% or less

You may not qualify if:

• adults unable to consent.
• individuals who are not yet adults (infants, children, teenagers).
• pregnant women.
• prisoners.
• vulnerable populations

Sponsors & Collaborators

• Northwestern University: lead
• University of Miami: collaborator
• University of Missouri-Columbia: collaborator
• National Institute on Deafness and Other Communication Disorders (NIDCD): collaborator

Study Sites (2)

University of Miami

Coral Gables, Florida, 33146, United States

Location

University of Missouri

Columbia, Missouri, 65212, United States

Location

MeSH Terms

Conditions

Hearing Loss

Interventions

Electric Stimulation

Condition Hierarchy (Ancestors)

Hearing Disorders; Ear Diseases; Otorhinolaryngologic Diseases; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Physical Stimulation; Investigative Techniques

Study Officials

• Claus-Peter Richter, MD, PhD

  Northwestern University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DEVICE FEASIBILITY
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 26, 2021
• First Posted: November 5, 2021
• Study Start: April 20, 2025
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: May 6, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: At publication of the results.
• Access Criteria: With the publication the study, de-identified data will be uploaded to a data repository and are accessible through figshare.com.

Locations

US (2)