Hearing Preservation in Pediatric Recipients of Cochlear Implants

Abstract

Objective: To determine factors that influence low-frequency hearing preservation following pediatric cochlear implantation and compare hearing preservation outcomes between 20 and 24 mm depth lateral wall electrodes. Study Design: Retrospective chart review. Setting: Tertiary academic referral center. Patients: Pediatric cochlear implant recipients (under the age of 18) who presented preoperatively with a low-frequency pure tone average (LFPTA; 125, 250 and 500 Hz) ≤ 70 dB HL. Intervention: Cochlear implantation Main Outcome Measures: Multiple logistic regression evaluating the influence of variables on change in LFPTA including preoperative low-frequency hearing, lateral wall or perimodiolar electrode, progressive vs stable hearing, side, time from surgery, and the presence or the absence of enlarged vestibular aqueduct. A second analysis reviews the 12-month postactivation hearing preservation of a subset of subjects implanted with modern lateral wall electrodes. Results: A total of 105 subjects were included from the last 10 years for our multiple logistic regression analysis. This demonstrated a significant correlation of poorer preoperative low-frequency hearing with change in LFPTA. A significant negative effect of electrode type, specifically perimodiolar electrodes was also seen. Forty-five subjects from the last 3 years undergoing cochlear implantation with a lateral wall electrode demonstrated an overall 12-month preservation rate (LFPTA < 90 dB) of 82%. Differences in preservation rates existed between different electrodes. Conclusion: Preservation of low-frequency hearing following cochlear implantation is predicted both by preoperative low-frequency hearing as well as type of electrode implanted. Consistent low-frequency hearing preservation is possible in pediatric subjects receiving lateral wall electrodes, although differences exist between electrode types.

Timing of Acoustic Hearing Changes After Cochlear Implantation

“…Two hundred and eleven subjects were used for the study-L24 (80), S8 (24), S12 (14), 422/522 (47), SRW (6), Flex (19), and SLIM J (21). Of these 211 subjects, 84 were omitted from the modeling analyses due to inadequate data (lack of audiometric test score for either 125, 250, and/or 500 Hz).…”

“…Better preoperative hearing has also been correlated with improved rates of long-term hearing preservation. 9,24 However, other studies have failed to support a correlation between these variables and degree of hearing loss after CI. 4,8,13,[25][26][27][28] A better understanding of how patient factors influence hearing outcomes could lead to improvements in CI candidate selection and provide further direction regarding choice of device type and insertion depth in specific populations.…”

“…Previous studies have suggested that individual patient factors, including age at implantation, 10,18–21 gender, 22 etiology of preoperative hearing loss, 22,23 and type of hearing loss 23 could impact long‐term hearing preservation rates. Better preoperative hearing has also been correlated with improved rates of long‐term hearing preservation 9,24 . However, other studies have failed to support a correlation between these variables and degree of hearing loss after CI 4,8,13,25–28 …”

Benefits of Cochlear Implantation in Childhood Unilateral Hearing Loss (CUHL Trial)

“…The benefit of combined electric and acoustic hearing has also been well‐demonstrated in children in whom low‐frequency hearing is preserved. 38 , 39 , 40 In addition, the benefit of the combination of acoustic hearing and a cochlear implant has also been well‐demonstrated with bimodal hearing in which patients with a cochlear implant benefit from a hearing aid in the contralateral, poor hearing ear. 41 , 42 Together these data suggest that auditory processing centers can integrate both electric and acoustic signals for an overall greater benefit for speech perception in both adults and children.…”

Acceptance and Benefit of Electroacoustic Stimulation in Children

“…Although not limited to children, Causon et al (39) found that individuals with stable hearing loss (as opposed to progressive loss) had a tendency toward higher rates of hearing preservation, which may in part explain the worse outcomes in children with EVA in our cohort, because EVA is typically associated with progressive loss. On the contrary, Selleck et al (17) did not find that progressive hearing loss was predictive of the ability to preserve hearing. Overall, although rates of hearing preservation may be less predictable than for idiopathic hearing loss, the current evidence suggests that hearing preservation is certainly a possibility in children with EVA, even in cases where a perilymphatic gusher is encountered (38).…”