Cochlear Implant Failure in the Pediatric Population

Hearing outcomes following reimplantation of functional legacy cochlear implants

OBJECTIVES

Recently, patients with certain legacy cochlear implants (CIs) have sought out reimplantation to enjoy the benefits offered by newer processor technology. This decision can be difficult, especially when the individual relies exclusively on the device for communication and scores at the ceiling of performance metrics. To date, most outcome data is derived from reimplantation of a non-functioning CI-a relatively easy decision. The aim of this study is to report hearing outcomes following reimplantation of legacy implants to guide surgeons and patients approaching this high-stakes clinical situation.

PATIENTS AND INTERVENTION

Four patients implanted with Advanced Bionics Clarion C1 devices over 20 years ago underwent reimplantation.

RESULTS

Three reimplanted patients demonstrated a maintenance or improvement in their audiometric performance with one patient experiencing only a 5 % decrease in AzBioQ score. Each patient expressed satisfaction with the expansion of technological capabilities including improved battery life, and device connectivity. There were no failed reimplantations or other adverse effects.

CONCLUSIONS

Reimplantation of a functioning legacy CI result in stability or improvement in auditory performance. All individuals in this series report that they enjoy the new connectivity and programming technologies. As the rate advancement in CI technology continues to increase and newer device architectures emerge, these data will help to inform the decision to reimplant functioning devices.

Cochlear Implant Revisions Over Three Decades of Experience

IMPORTANCE

The indications, technology, and surgical technique for cochlear implantation have evolved over the last three decades. Understanding the risk of cochlear implant revision (CIR) is important for patient counseling.

OBJECTIVE

The objective of this study was to analyze the rates, indications, and audiologic outcomes for CIR over three decades of experience at a single academic medical center.

DESIGN

A retrospective chart review was performed at a single academic medical center for individuals who underwent cochlear implantation between 1985 and 2022.

SETTING

Single academic medical center.

PARTICIPANTS

Three thousand twenty-five individuals who underwent 3,934 cochlear implant operations from 1985 to 2022.

EXPOSURE

Cochlear implantation.

MAIN OUTCOMES AND MEASURES

Rates, indications, risk factors, and audiologic outcomes for CIR.

RESULTS

There were 276 cases of CIR after primary implantation and an overall revision rate of 7.6% (95% confidence interval, 6.8-8.5%) over 37 years of follow-up with many cases of CIR secondary to Advanced Bionics vendor B and field action failure groups. CIR rates increased sharply through the early and mid-2000s and have since remained stable. Hard or soft device failure was the most common indication for CIR, accounting for 73% of cases. Pediatric patient status and previous CIR were associated with an increased risk of CIR. Audiologic outcomes after CIR were similar to those before device failure.

CONCLUSIONS AND RELEVANCE

CIR remains a common procedure most often performed for device failure. Pediatric patients and those who have undergone previous CIR are at the highest risk for future CIR. Audiologic outcomes remain stable after CIR, and these data will help providers counsel patients at the risk of future CIR and understand the risk factors associated with CIR.

Infected Cochlear Implant and Re-implantation in a Pediatric Case

Cochlear implant (CI) surgery is relatively safe, however reports of complications and failure following cochlear implant surgery are higher nowadays due to the increasing number of patients with CI. Herein, we report a case of infected cochlear implant 10 months after surgery. A three-year-six-month-old girl underwent right cochlear implantation for bilateral profound sensorineural hearing loss. From day one until six months after the surgery, it was uneventful and the wound healed well. However, at 10 months post-surgery, she presented with a chronic discharging wound over the previous surgical site. Despite being on IV antibiotics for six weeks and daily dressing, the wound over the implant site keep discharging and eventually the implant was removed two months later. She was later re-implanted with a cochlear implant on the same side at the age of five years 10 months old. Currently, she is showing good speech improvement with the right CI. Her aided hearing threshold is at 30-40 dB at all frequencies. Early diagnosis is crucial, and the proper course of action should be taken as soon as possible if implant failure is suspected. Prior to implant surgery, any potential risk factors that could lead to implant failure should be identified and addressed appropriately to reduce the risk of an infected cochlear implant.

Suitable Electrode Choice for Robotic-Assisted Cochlear Implant Surgery: A Systematic Literature Review of Manual Electrode Insertion Adverse Events

Background and Objective

The cochlear implant (CI) electrode insertion process is a key step in CI surgery. One of the aims of advances in robotic-assisted CI surgery (RACIS) is to realize better cochlear structure preservation and to precisely control insertion. The aim of this literature review is to gain insight into electrode selection for RACIS by acquiring a thorough knowledge of electrode insertion and related complications from classic CI surgery involving a manual electrode insertion process.

Methods

A systematic electronic search of the literature was carried out using PubMed, Scopus, Cochrane, and Web of Science to find relevant literature on electrode tip fold over (ETFO), electrode scalar deviation (ESD), and electrode migration (EM) from both pre-shaped and straight electrode types.

Results

A total of 82 studies that include 8,603 ears implanted with a CI, i.e., pre-shaped (4,869) and straight electrodes (3,734), were evaluated. The rate of ETFO (25 studies, 2,335 ears), ESD (39 studies, 3,073 ears), and EM (18 studies, 3,195 ears) was determined. An incidence rate (±95% CI) of 5.38% (4.4–6.6%) of ETFO, 28.6% (26.6–30.6%) of ESD, and 0.53% (0.2–1.1%) of EM is associated with pre-shaped electrodes, whereas with straight electrodes it was 0.51% (0.1–1.3%), 11% (9.2–13.0%), and 3.2% (2.5–3.95%), respectively. The differences between the pre-shaped and straight electrode types are highly significant (p < 0.001). Laboratory experiments show evidence that robotic insertions of electrodes are less traumatic than manual insertions. The influence of round window (RW) vs. cochleostomy (Coch) was not assessed.

Conclusion

Considering the current electrode designs available and the reported incidence of insertion complications, the use of straight electrodes in RACIS and conventional CI surgery (and manual insertion) appears to be less traumatic to intracochlear structures compared with pre-shaped electrodes. However, EM of straight electrodes should be anticipated. RACIS has the potential to reduce these complications.