Outcomes and Predictive Factors of Electroacoustic Stimulation Rehabilitation in Children With Limited Low-Frequency Hearing

Benefits of Cochlear Implantation and Hearing Preservation for Children With Preoperative Functional Hearing: A Prospective Clinical Trial

OBJECTIVES

This study was designed to (1) compare preactivation and postactivation performance with a cochlear implant for children with functional preoperative low-frequency hearing, (2) compare outcomes of electric-acoustic stimulation (EAS) versus electric-only stimulation (ES) for children with versus without hearing preservation to understand the benefits of low-frequency acoustic cues, and (3) to investigate the relationship between postoperative acoustic hearing thresholds and performance.

DESIGN

This was a prospective, 12-month between-subjects trial including 24 pediatric cochlear implant recipients with preoperative low-frequency functional hearing. Participant ages ranged from 5 to 17 years old. They were recruited at their device activation and fit with EAS or ES based on their postoperative thresholds. Group outcomes were compared for single-word recognition, masked sentence recognition, perceived hearing abilities, speech production, receptive language, expressive language, and prosodic identification.

RESULTS

Children experienced improvements in word recognition, subjective hearing, speech production, and expressive language with EAS or ES as compared with their preoperative abilities. Children using EAS performed better on a prosodic identification task and had higher subjective hearing scores postactivation as compared with children using ES. There was a significant relationship between postoperative thresholds at 125 Hz and prosodic identification.

CONCLUSIONS

The results of this study support cochlear implantation for children with normal-to-moderate low-frequency hearing thresholds and severe-to-profound high-frequency hearing loss. They also highlight the benefits of postoperative hearing preservation for language development.

Acceptance and Benefit of Electroacoustic Stimulation in Children

OBJECTIVE

Children with high-frequency severe-to-profound hearing loss and low-frequency residual hearing who do not derive significant benefit from hearing aids are now being considered for cochlear implantation. Previous research shows that hearing preservation is possible and may be desirable for the use of electroacoustic stimulation (EAS) in adults, but this topic remains underexplored in children. The goal of this study was to explore factors relating to hearing preservation, acceptance, and benefits of EAS for children.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary academic medical center.

PATIENTS

Forty children (48 ears) with preoperative low-frequency pure-tone averages of 75 dB HL or less at 250 and 500 Hz (n = 48).

INTERVENTION

All patients underwent cochlear implantation with a standard-length electrode.

MAIN OUTCOME MEASURE

Low-frequency audiometric thresholds, speech perception, and EAS usage were measured at initial stimulation, and 3 and 12 months postoperatively. Outcomes were compared between children with and without hearing preservation, and between EAS users and nonusers.

RESULTS

Hearing was preserved at similar rates as adults but worse for children with an enlarged vestibular aqueduct. Fewer than half of children who qualified to use EAS chose to do so, citing a variety of audiologic and nonaudiologic reasons. No differences were detected in speech perception scores across the groups for words, sentences, or sentences in noise tests.

CONCLUSIONS

Neither hearing preservation nor EAS use resulted in superior speech perception in children with preoperative residual hearing; rather, all children performed well after implantation.

The benefits of preserving residual hearing following cochlear implantation: a systematic review

OBJECTIVE

Systematically review the current literature for evidence on the "real-life" benefits of hearing preservation cochlear implantation (HPCI) for children and adults.

DESIGN

Systematic search of Pubmed, MEDLINE, EMBASE, CINHAL and Cochrane Library for MesH terms hearing¸ preservation and cochlear implantation. Inclusion criteria were the "real-life" benefit of HPCI i.e. other than pre- and post-operative pure tone thresholds. Exclusion criteria were non-English language, conference abstracts, reviews and animal and cadaveric studies. Risk of bias was assessed using the Evidence Project Tool.

STUDY SAMPLE

37 studies that matched criteria for review with 8/37 including children and 29/37 including adults.

RESULTS

HPCI was associated with better speech perception in noise in 18/26 papers and better music perception in 4/5 papers. There was no significant benefit reported in speech perception in quiet (14/20 papers) or binaural cues (3/4 papers), nor was there convincing evidence of HPCI outperforming bimodal users (5/7 papers). QoL scores were high amongst HPCI patients (2/2 papers). Interpretation of findings was hindered by small study groups and significant heterogeneity in various parameters.

CONCLUSION

Current literature on the "real-life" benefit of HPCI, although limited, supports the existence of meaningful benefit, especially in speech perception in noise and music perception.