Cochlear Implants for Adults With Single-sided Deafness (SSD)

Cochlear Implantation for Single-Sided Deafness

The purpose of this investigation is to determine the safety and preliminary efficacy of implanting a cochlear implant (CI) in the profoundly deaf ear of an adult with one normal hearing (NH) ear (termed "single-sided deaf" person, or SSD). The potential subjects will have been deafened post-lingually, thus, at one point the now deafened ear did conduct sound from the periphery. The MED-EL CI system will be implanted in ten (10) SSD patients.The long-term goal of this research program is to determine whether the CI, in combination with the NH ear, may provide improved localization ability and better speech understanding in noise, relative to performance before cochlear implantation (i.e., with the NH ear alone). A secondary long-term goal is to determine whether CI stimulation may reduce tinnitus severity, compared to tinnitus experienced prior to cochlear implantation or when the CI is turned off, after implantation.

Study Overview

• Status: Unknown
• Conditions: Single-sided Deafness
• Intervention / Treatment: Device: MED-EL Maestro Cochlear Implant

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90057
      • House Clinic
    • Los Angeles, California, United States, 90007
      • Keck School of Medicine of USC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Is an adult (18 years of age or older)
• English as the primary language
• Able to undergo general anesthesia, as determined by physical examination and written report from the physician
• Receives pneumovax vaccine within 2 weeks of surgery and provides documentation to the principal investigator

• Profoundly/severely deaf in one ear ("implant ear"), as defined by:

  • 3-frequency pure-tone average≥70 dB Hearing Loss
  • Bone conduction thresholds consistent with air conduction thresholds (i.e., no conductive component to the hearing loss)
  • HINT sentence recognition score ≤40% correct, 60 dBA presentation level
  • Post-lingual onset of hearing loss, i.e., after age 6 years of age
  • Hearing loss occurred <10 years prior, as obtained by history

• Normal hearing in one ear ("non-implant ear"), as defined by:

  • 3-frequency PTA ≤25 dB HL
  • No tested frequency air conduction threshold >35 dB HL
  • Bone conduction thresholds consistent with air conduction thresholds
  • Word recognition score ≥80% correct, 60 dBA presentation level
  • HINT sentence recognition score ≥ 80%, 60 dBA presentation level
• Provides informed consent
• Willing and able to follow the study protocol

Exclusion Criteria:

• Retrocochlear pathology resulting from Neurofibromatosis 2, or other types of cranial nerve/brainstem tumors
• Co-existing medical conditions that require radiotherapy of the brainstem and/or auditory cortex

• Any medical contraindication precluding safe administration of general anesthesia, e.g.,

  • Cardiopulmonary disease
  • Renal disease

• Otologic conditions which contraindicate surgery

  • Active middle ear infection
  • Tympanic membrane perforation
• Anatomic abnormalities detected on CT preventing appropriate placement of the stimulator housing in the bone of the skull or placement of the electrode array in the cochlea (e.g., ossification)
• Psychological conditions contraindicating surgery
• Skin or scalp conditions that may preclude attachment of the coil or that may interfere with the use of the coil
• Chronic pain in or around the head
• Current or previous use of an active hearing implant (e.g., bone-anchored hearing aids, cochlear implant, etc.)
• Developmental delays or organic brain dysfunction

Study Plan

How is the study designed?

Design Details

• Primary Purpose: DEVICE_FEASIBILITY
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Open-label; Cochlear Implant	Device: MED-EL Maestro Cochlear Implant; cochlear implant

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pure-tone threshold average (dB)	Change in 3-frequency pure-tone threshold average (dB) in the normal hearing ear.	6 months post-activation
Hearing in Noise Test (signal-to-noise ratio)	Change in Hearing in Noise Test signal-to-noise ratio in the normal hearing ear.	6 months post-activation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse Events	Number of unexpected serious adverse events across all 10 subjects.	1-month post-implantation

Collaborators and Investigators

• Sponsor: Robert Shannon
• Collaborators: University of California, Los Angeles; House Clinic, Inc.; Med-El Corporation
• Investigators: Principal Investigator: Robert Shannon, PhD, Keck School of Medicine of USC

Study record dates

Study Major Dates

• Study Start: September 1, 2014
• Primary Completion (ANTICIPATED): June 1, 2019
• Study Completion (ANTICIPATED): September 1, 2019

Study Registration Dates

• First Submitted: September 26, 2014
• First Submitted That Met QC Criteria: October 3, 2014
• First Posted (ESTIMATE): October 8, 2014

Study Record Updates

• Last Update Posted (ACTUAL): April 20, 2017
• Last Update Submitted That Met QC Criteria: April 18, 2017
• Last Verified: April 1, 2017

More Information

Terms related to this study

• Keywords: cochlear implant; deaf adult; single-sided
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Otorhinolaryngologic Diseases; Ear Diseases; Sensation Disorders; Hearing Disorders; Hearing Loss; Deafness
• Other Study ID Numbers: CI for SSD adults