Cochlear Implantation in Elderly Patients with Residual Hearing

Abstract

This retrospective study aimed to investigate the range of hearing levels in a cochlear implant (CI) elderly population receiving electric-acoustic-stimulation (EAS) or electric-stimulation (ES) alone. The investigation evaluates the degree of hearing preservation (HP) and the speech comprehension resulting from EAS or ES-only to identify audiometric factors that predict adequate EAS and ES use. We analyzed the pure tone audiometry and speech perception in quiet and noise preoperatively and 12-months after activation of 89 elderly adults (age of 65 years old or older), yielding in total 97 CIs. Thirty-two (33.1%) patients were potential EAS candidates preoperatively, of which 18 patients used EAS at the time of first fitting and the other 14 patients continued to use their residual hearing for EAS at 12-months. Post-treatment, patients with EAS system and ES-only users’ with longer electrodes showed better results in monosyllable word scores in quiet than ES-only users with shorter electrodes. A similar trend was revealed for the speech recognition in noise. Patients with an EAS system benefit from maintaining their natural residual hearing. Nevertheless, strict preoperative patient selection is warranted particularly in elderly patients, in whom the hearing thresholds for EAS indication differ slightly from that in younger adults.

Cochlear Implantation in Hearing-Impaired Elderly: Clinical Challenges and Opportunities to Optimize Outcome

“… Matin et al (2021) recommend a very careful selection of EAS use in the elderly. It is necessary to pay particular attention to the preoperative frequencies 250 and 500 Hz.…”

“…Speech comprehension also in the elderly is better in patients with deeper insertion angles and wider cochlear coverage. The results with only the longer electrode (FLEX 28) and electric stimulation show significantly better results than speech comprehension with only the shorter electrode (FLEX 20) and electric stimulation ( Matin et al, 2021 ). The hearing thresholds for the EAS indication differ by up to 20 dB between 125 and 500 Hz compared to younger adults.…”

“…Cochlear fragility can be caused by osteoporosis and increased fracture risk ( Singh et al, 2018 ). To date, to our knowledge, there has been only one study examining the extent of hearing preservation with various thin flexible lateral-wall electrodes and the outcome in speech comprehension 12 months after CI in 89 elderly patients over 65 years ( Matin et al, 2021 ). These results demonstrate as well that hearing preservation in elderly patients with CI is feasible 12 months after activation with shorter electrode arrays—despite concerns about increased susceptibility to trauma in these patients.…”

“…Compared to other studies, the loss of residual hearing was slightly greater in elderly patients, but after a period of 12 months, this difference was no longer observed ( Suhling et al, 2016 ). The authors suspect age-degenerative processes as the cause of the greater hearing loss in the low frequencies ( Matin et al, 2021 ). Speech comprehension also in the elderly is better in patients with deeper insertion angles and wider cochlear coverage.…”

“…It is calculated that the preoperative limit for EAS provision in elderly patients is 42.5 dB at 250 Hz and 52.5 dB at 500 Hz to achieve sufficient benefit. Therefore, the preoperative score for monosyllables (unaided) should not fall below 32.5% ( Matin et al, 2021 ).…”