Comparison of a Mid Scala and a Perimodiolar Electrode in Adults: Performance, Impedances, and Psychophysics

Abstract

Objectives: The HiFocus Mid-Scala electrode array (HFms) is designed to sit within the scala tympani without touching either the lateral wall or the modiolus. The aim of this study was to compare the HFms to the Helix perimodiolar electrode array. Method: Two groups of recipients with Helix (n = 22 ears) and HFms (n = 29 ears) electrode arrays were retrospectively identified and matched by age at implantation and duration of severe to profound deafness. Most comfortable listening levels (M), impedances, Freiburger Monosyllables in quiet, and Oldenburg sentences in adaptive noise were compared at 3, 6, and 12 months postimplant. Results: Median scores for monosyllables in quiet for the HFms group were significantly better than the Helix group at each test interval (p < 0.05). Speech perception in quiet also significantly improved from 3 to 12 months for both groups (p < 0.001). There was no significant difference between the groups for speech in noise. Impedances were significantly lower for the HFms group at 12 months (p < 0.05) except at the basal end and M levels were generally higher. Conclusions: The HFms group had better median performance for monosyllables in quiet than the Helix group at each test interval, although performance in noise was similar. For speech in noise, the HFms group appear to reach optimum performance quicker than the Helix group. Impedances were lower in the HFms group across the array, other than at the most basal end, and support our hypothesis that the HFms assumes a more lateral position within the cochlea than the Helix electrode, although our article did not include imaging data.

A Multicenter Comparison of 1-yr Functional Outcomes and Programming Differences Between the Advanced Bionics Mid-Scala and SlimJ Electrode Arrays

“…This aligns with recent studies reporting no significant difference on sentence or disyllabic tests between modern precurved and straight arrays (13,50–55). However, some studies have reported better performance for PM arrays on electrode discrimination (13), listening effort (13), and consonant nucleus consonant tests (47,51,55,56).…”

Functional Outcomes and Quality of Life after Cochlear Implantation in Patients with Long-Term Deafness

“…Additionally, MSE achieved a more consistent insertion depth than HiFocus 1J [ 39 , 41 ]. Battmer et al compared the MSE with the Helix perimodiolar electrode array and they found that cochlear implantation with MSE led to significantly better postoperative SIM in quiet at each control interval from 3 to 12 months, at the same time, performance of both electrodes was in noise similar [ 42 ]. However, the biggest study to date with n = 328 participants comparing the outcome of MSE, lateral wall (LW) and perimodiolar (PM) electrodes showed no significant differences in hearing results [ 43 ].…”

Comparison of speech perception in bimodal cochlear implant patients with respect to the cochlear coverage

“…Paramount for the success of cochlear implants (CI) is the individualized care of each patient The CI team takes into account the diverse (patho)physioanatomical characteristics of each patient, including inner ear malformations [ 1 ], residual hearing [ 2 , 3 ], prevention of vertigo [ 4 ], and the wide range of cochlear duct lengths (CDL; [ 5 – 7 ]). Different CI manufacturers offer a selection of electrodes with carrying lengths and locations within the cochlea [ 8 – 11 ]. The modality should also be considered when fitting both ears.…”