Clinical Utility of Residual Hearing in the Cochlear Implant Ear

Overview

About this study

The primary objective of this study is to determine the hearing preservation advantage, defined as the increased chance of preservation of residual hearing (i.e., low frequency pure tone average ≤ 80 dB HL), of ECochG-guided CI electrode insertions in EAS candidates.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Provision of signed and dated informed consent form.
  • Adults, males and females, ages 18 -79 who have a bilateral sensorineural hearing loss with postlingual onset.
  • Minimum of 30 days experience with appropriately fit binaural amplification (standardized NAL fitting method) verified with real ear measurements within 5 dB SPL of targets.
  • Limited benefit from conventional amplification in the best aided condition as defined by test scores of:
    • The ear to implanted: CNC words ≤ 60% or AzBio sentences (+10, +5 dB SNR ≤ 60% correct);
    • Contralateral ear: ≤ 80% on CNC words or AzBio sentences (+10, +5 dB SNR ≤ 80% correct);
    • Low frequency Pure Tone Average (PTA- 125, 250, 500 Hz) ≤ 55 dB HL in the ear to be implanted;
    • Severe to profound mid to high-frequency sensorineural hearing loss (threshold average of 1000, 2000, 3000, and 4000 Hz ≥75 dB HL) in the ear to be implanted;
    • Low frequency PTA ≤ 55 dB HL sloping to moderately severe to profound mid-to high frequency sensorineural hearing loss (threshold average of 1000, 2000, 3000, 4000 Hz ≥ 60 dB) in the contralateral ear.
  • Proficient in English.
  • Undergoing implantation with a current generation cochlear implant device from either Cochlear Limited or Advanced Bionics AG.
  • Cochlear Limited devices include: Nucleus CI612, CI622, CI632, CI624.
  • Advanced Bionics AG devices include:  HiFocus SlimJ, Mid-Scala.
  • Stated willingness and ability to complete testing and all associated study visits.

Exclusion Criteria:

  • An individual who meets any of the following criteria will be excluded from participation in this study:
    • Previous cochlear implantation;
    • Prelingual onset of hearing loss;
    • Abnormal inner ear anatomy on CT imaging;
    • Auditory neuropathy spectrum disorder;
    • Retrocochlear pathology such as a vestibular schwannoma or stroke.
  • Unwillingness or inability to comply with all investigational requirements including the randomization process.
  • Additional medical, or social barriers that would prevent completion of all study requirements.
  • Medical condition contraindicated for surgery.
  • Device selection of Med El cochlear implant (per the patient’s selection).

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Aniket Saoji, Ph.D.

Open for enrollment

Contact information:

Ashlee Kirtz

(507) 284-1231

Kirtz.Ashlee@mayo.edu

More information

Publications

  • To report the use of multi-frequency intra-cochlear electrocochleography (ECOG) in monitoring and optimizing electrode placement during cochlear implant surgery. An acoustic pure tone complex comprising of 250, 500, 1000, and 2000 Hz was used to elicit ECOG, or more specifically cochlear microphonics (CMs), responses from various locations in the cochlea. The most apical cochlear implant electrode was used as the recording electrode. Read More on PubMed
  • The preservation of residual hearing is becoming increasingly important in cochlear implant surgery. Conserving residual hearing is a positive prognostic indicator for improved hearing abilities. Read More on PubMed
  • To demonstrate the safety and effectiveness of the MED-EL Electric-Acoustic Stimulation (EAS) System, for adults with residual low-frequency hearing and severe-to-profound hearing loss in the mid to high frequencies. Read More on PubMed
  • Intraoperative, intracochlear electrocochleography (ECochG) will provide a means to monitor cochlear hair cell and neural response during cochlear implant (CI) electrode insertion. Distinct patterns in the insertion track can be characterized. Read More on PubMed
  • This retrospective review explores delayed-onset hearing loss in 85 individuals receiving cochlear implants designed to preserve acoustic hearing at the University of Iowa Hospitals and Clinics between 2001 and 2015. Repeated measures of unaided behavioral audiometric thresholds, electrode impedance, and electrically evoked compound action potential (ECAP) amplitude growth functions were used to characterize longitudinal changes in auditory status. Participants were grouped into two primary categories according to changes in unaided behavioral thresholds: (1) stable hearing or symmetrical hearing loss and (2) delayed loss of hearing in the implanted ear. Thirty-eight percent of this sample presented with delayed-onset hearing loss of various degrees and rates of change. Neither array type nor insertion approach (round window or cochleostomy) had a significant effect on prevalence. Electrode impedance increased abruptly for many individuals exhibiting precipitous hearing loss; the increase was often transient. The impedance increases were significantly larger than the impedance changes observed for individuals with stable or symmetrical hearing loss. Moreover, the impedance changes were associated with changes in behavioral thresholds for individuals with a precipitous drop in behavioral thresholds. These findings suggest a change in the electrode environment coincident with the change in auditory status. Changes in ECAP thresholds, growth function slopes, and suprathreshold amplitudes were not correlated with changes in behavioral thresholds, suggesting that neural responsiveness in the region excited by the implant is relatively stable. Further exploration into etiology of delayed-onset hearing loss post implantation is needed, with particular interest in mechanisms associated with changes in the intracochlear environment. Read More on PubMed
  • To determine whether electrocochleography (ECoG) thresholds, especially cochlear microphonic and auditory nerve neurophonic thresholds, measured using an intracochlear electrode, can be used to predict pure-tone audiometric thresholds following cochlear implantation in ears with residual hearing. Read More on PubMed
  • Before 1964, electrocochleography (ECochG) was a surgical procedure carried out in the operating theatre. Currently, the newest application is also an intra-operative one, often carried out in conjunction with cochlear implant surgery. Starting in 1967, the recording methods became either minimal- or not-invasive, i.e., trans-tympanic (TT) or extra tympanic (ET), and included extensive studies of the arguments pro and con. I will review several valuable applications of ECochG, from a historical point of view, but covering all 75 years if applicable. The main topics will be: (1) comparing human and animal cochlear electrophysiology; (2) the use in objective audiometry involving tone pip stimulation-currently mostly pre cochlear implantation but otherwise replaced by auditory brainstem response (ABR) recordings; (3) attempts to diagnose Ménière's disease and the role of the summating potential (SP); (4) early use in diagnosing vestibular schwannomas-now taken over by ABR screening and MRI confirmation; (5) relating human electrophysiology to the effects of genes as in auditory neuropathy; and (6) intracochlear recording using the cochlear implant electrodes. The last two applications are the most recently added ones. The "historical aspects" of this review article will highlight the founding years prior to 1980 when relevant. A survey of articles on Pubmed shows several ups and downs in the clinical interest as reflected in the publication counts over the last 75 years. Read More on PubMed
  • The concept of expanding electrical speech processing to those with more residual acoustic hearing with a less-invasive shorter cochlear implant (CI) has been ongoing since 1999. A multicenter study of the Nucleus Hybrid S8 CI took place between 2002 and 2011. This report describes the final outcomes of this clinical trial. Read More on PubMed
  • To monitor cochlear function during cochlear implantation and determine correlations with postoperative acoustic hearing. Read More on PubMed
  • The primary objective of this study was to determine whether a revision and/or expansion of current audiologic cochlear implant candidacy criteria is warranted. Read More on PubMed
  • A so far unattained high rate (100%) of residual hearing preservation in cochlear implantation for electric-acoustic stimulation could be achieved using sophisticated surgical techniques in combination with the MedEl Flex EAS electrode. Read More on PubMed
  • Acoustic plus electric (electric-acoustic) speech processing has been successful in highlighting the important role of articulation information in consonant recognition in those adults that have profound high-frequency hearing loss at frequencies greater than 1500 Hz and less than 60% discrimination scores. Eighty-seven subjects were enrolled in an adult Hybrid multicenter Food and Drug Administration clinical trial. Immediate hearing preservation was accomplished in 85/87 subjects. Over time (3 months to 5 years), some hearing preservation was maintained in 91% of the group. Combined electric-acoustic processing enabled most of this group of volunteers to gain improved speech understanding, compared to their preoperative hearing, with bilateral hearing aids. Most have preservation of low-frequency acoustic hearing within 15 dB of their preoperative pure tone levels. Those with greater losses (>30 dB) also benefited from the combination of electric-acoustic speech processing. Postoperatively, in the electric-acoustic processing condition, loss of low-frequency hearing did not correlate with improvements in speech perception scores in quiet. Sixteen subjects were identified as poor performers in that they did not achieve a significant improvement through electric-acoustic processing. A multiple regression analysis determined that 91% of the variance in the poorly performing group can be explained by the preoperative speech recognition score and duration of deafness. Signal-to-noise ratios for speech understanding in noise improved more than 9 dB in some individuals in the electric-acoustic processing condition. The relation between speech understanding in noise thresholds and residual low-frequency acoustic hearing is significant (r = 0.62; p < 0.05). The data suggest that, in general, the advantages gained for speech recognition in noise by preserving residual hearing exist, unless the hearing loss approaches profound levels. Preservation of residual low-frequency hearing should be considered when expanding candidate selection criteria for standard cochlear implants. Duration of profound high-frequency hearing loss appears to be an important variable when determining selection criteria for the Hybrid implant. Read More on PubMed
  • A new technique for determining the position of each electrode in the cochlea is described and applied to spiral computed tomography data from 15 patients implanted with Advanced Bionics HiFocus I, Ij, or Helix arrays. Read More on PubMed
  • The goals of this work were (a) to review the pre- and postsurgical auditory thresholds in a consecutive sample of cochlear implant recipients to determine the fate of residual hearing, and (b) to obtain preliminary indication of the value of a multicenter longitudinal study of residual hearing in implant patients. Read More on PubMed
  • In clinical trial data monitoring, one can either introduce a discrete sequential boundary for a set of specified decision times or adopt a use function and then derive the boundary when data are monitored. If the use function approach is employed, one can adjust the frequency of data monitoring as long as the decision is not data-dependent. However, if the frequency of future data monitoring is affected by the observed data, then the probability of Type I error will no longer be preserved exactly. But the effect on the significance level and power is very small, perhaps negligible, as indicated by simulation results. Read More on PubMed