Identifying electrode migration post cochlear implantation in children and its correlation with speech outcome.

OBJECTIVE

This study aims to identify early electrode migration after cochlear implant (CI) surgery using imaging, mapping, and postoperative auditory and speech scores in order to enhance the performance of the implant and its outcome. STUDY

DESIGN

A prospective study involving the bilaterally profound hearing-impaired children who underwent cochlear implantation from January 2021 to February 2024.

SETTING

Patients who attended the paediatric hearing clinic in a tertiary care hospital for follow-up after 6 months to 1 year were recruited.

METHODS

After a minimum of 6 months of cochlear implantation surgery, a ‘modified Stenver’s view’ and a ‘cochlear view’ mastoid x-ray was done to determine the electrode position, insertion depth and degree of insertion and compared with the x-ray taken on post-operative day one. The electrode position was then correlated with electrically evoked compound action potential (ECAP), impedance, CAP-12 (Categories of auditory performance) score and speech intelligibility rating (SIR).

RESULTS

Out of 35 patients who enrolled for the study, 3 patients were found to have electrode migration, of which one patient had poor speech and auditory outcome. The cochlear view was found to be superior to modified Stenver’s view.

CONCLUSIONS

Electrode migration is a rare but not uncommon complication that may not be easily picked up with ECAP and impedance monitoring in the post-operative period, warranting regular imaging such as cochlear view x-ray that is fast, cheap and has low radiation exposure to children. It also gives good electrode visibility and can determine the electrode position, angular insertion depth and electrode migration.