The French National Cochlear Implant Registry (EPIIC): Bilateral cochlear implantation

Bilateral simultaneous cochlear implants in children: Best timing of surgery and long-term auditory outcomes

PURPOSE

Evaluate the hearing outcomes of bilateral deaf children implanted simultaneously and define the most appropriate timing for surgery.

MATERIALS AND METHODS

Audiological CI results were retrieved in both the short-term and long-term period and compared by stratifying the patients into different subcohorts according to their age at surgery. Additional data collected were age at implant activation, etiology and timing of onset of deafness, presence of psychomotor delay.

RESULTS

fifty-six bilaterally implanted children were included. The short-term outcomes differed significantly when comparing groups of different ages at implantation: younger patients achieved better aided pure tone audiometry results. Considering long-term follow-up, a significant correlation was identified between an early age at implantation and the hearing outcome at ages 2 to 5 years. Perceptive levels were better at 4 years of age in the younger group. No significant differences were found between children implanted at before 12 months and between 12 and 16 months of age.

CONCLUSIONS

The results of the analyzed follow-up data support the hypothesis that children implanted at before 24 months are expected to have better hearing performances. Nevertheless, these results are referred to a widely heterogeneous group of patients and the duration of auditory deprivation should be considered.

Validation of the Swedish Quality Register for Ear Surgery - SwedEar

BACKGROUND

The Swedish Quality Register for Ear Surgery (SwedEar) is a national register monitoring surgical procedures and outcomes of ear surgery to facilitate quality improvement. The value of the register is dependent on the quality of its data. SwedEar has never been validated regarding data quality or missing entries. Therefor, the purpose of this study was to assess coverage, completeness and response rate in the register and validate the physicians' reported data accuracy.

METHODS

In this validation study, the completeness, response rate and missing registrations were analysed. Data in SwedEar were compared with the yearly collected statistics of otosurgical procedures in The Swedish Otosurgical Society and the comparison of rates between groups was calculated with Fisher's exact test. Validation of registered data accuracy was performed on every 20th registered case during a five-year period. Data were reabstracted from medical records and compared with the original registration. Interrater agreement, reliability measures, Cohen's kappa, Gwet's AC1 and positive predictive value were calculated.

RESULTS

SwedEar has a coverage of 100%. The completeness of registered cases was 84% and the response rate was 74%. The validation of data accuracy assessed 13 530 variables, including audiograms. Less than 3% of incorrect or missing variables were identified. For most of the pre- and postoperative variables the Kappa and Gwet´s AC1 results show an almost perfect agreement (> 0.80). For audiogram data the ICC shows an excellent reliability (> 0.9) for all but one value.

CONCLUSION

This validation shows that SwedEar has excellent coverage, high completeness, and that the data in the register have almost perfect reliability. The data are suitable for both clinical and research purposes. Further efforts to improve completeness are warranted.

Bilateral cochlear implantation

Binaural hearing has certain benefits while listening in noisy environments. It provides the listeners with access to time, level and spectral differences between sound signals, perceived by the two ears. However, single sided deaf (SSD) or unilateral cochlear implant (CI) users cannot experience these binaural benefits due to the acoustic input coming from a single ear. The translational research on bilateral CIs started in the year 1998, initiated by J. Müller and J. Helms from Würzburg, Germany in association with MED-EL. Since then, several clinical studies were conducted by different research groups from across the world either independently or in collaboration with MED-EL. As a result, the bilateral CI has become the standard of care in many countries along with reimbursement by the health care systems. Recent data shows that children particularly, are given high priority for the bilateral CI implantation, most often performed simultaneously in a single surgery, as the binaural hearing has a positive effect on their language development. This article covers the milestones of translational research from the first concept to the widespread clinical use of bilateral CI.