Auditory brainstem implantation (ABI) in children without neurofibromatosis type II (NF2): communication performance and safety after 24 months of use

Auditory performance and language skills in children with auditory brainstem implants and cochlear implants

PURPOSE

This study aims to evaluate school-age language skills and auditory performance in different listening situations in children with cochlear implants and auditory brainstem implants.

METHOD

The study included 60 children between the ages of 5 and 9 years with cochlear implants (CI) and auditory brainstem implants (ABI). The volunteer children were divided into two groups: bimodal CI-ABI and bilateral CI users. Test of Language Development: Primary (TOLD-P:4), which assesses components of language such as phonology, morphology, syntax and semantics, was used to evaluate school-age language skills. Children's Auditory Performance Scale (CHAPS) was used to measure their listening performance in quiet, noisy, multi-stimulus environments and their auditory attention and memory skills in daily life. The correlations between language and auditory performance were analyzed and compared between the two groups.

RESULTS

Children with ABI showed poorer performance in school-age language skills and auditory performance in different listening environments (p < 0.05). Significant correlations were between school-age language skills and auditory performance (p < 0.05).

CONCLUSION

Improved auditory performance is crucial for the development of school-age language skills. To improve auditory performance in children with ABI in different listening environments, assistive listening devices, acoustic environmental arrangements, informative activities, etc., should be used.

Auditory Brainstem Implant Outcomes in Tumor and Nontumor Patients: A Systematic Review

OBJECTIVE

To elucidate the differences in auditory performance between auditory brainstem implant (ABI) patients with tumor or nontumor etiologies.

DATA SOURCES

PubMed, Embase, and Web of Science Core Collection from 1990 to 2021.

REVIEW METHODS

We included published studies with 5 or more pediatric or adult ABI users. Auditory outcomes and side effects were analyzed with weighted means for closed-set, open-set speech, and categories of auditory performance (CAP) scores. Overall performance was compared using an Adult Pediatric Ranked Order Speech Perception (APROSPER) scale created for this study.

RESULTS

Thirty-six studies were included and underwent full-text review. Data were extracted for 662 tumor and 267 nontumor patients. 83% were postlingually deafened and 17% were prelingually deafened. Studies that included tumor ABI patients had a weighted mean speech recognition of 39.2% (range: 19.6%-83.3%) for closed-set words, 23.4% (range: 17.2%-37.5%) for open-set words, 21.5% (range: 2.7%-48.4%) for open-set sentences, and 3.1 (range: 1.0-3.2) for CAP scores. Studies including nontumor ABI patients had a weighted mean speech recognition of 79.8% (range: 31.7%-84.4%) for closed-set words, 53.0% (range: 14.6%-72.5%) for open-set sentences, and 2.30 (range: 2.0-4.7) for CAP scores. Mean APROSPER results indicate better auditory performance among nontumor versus tumor patients (3.5 vs 3.0, P = .04). Differences in most common side effects were also observed between tumor and nontumor ABI patients.

CONCLUSION

Auditory performance is similar for tumor and nontumor patients for standardized auditory test scores. However, the APROSPER scale demonstrates better ABI performance for nontumor compared to tumor patients.

Auditory Brainstem Implants in Children with Inner Ear Anomalies: An Indian Perspective

Auditory brainstem implantation (ABI) is a viable option for individuals with inner ear anomalies, or other retro-cochlear pathologies, where cochlear implantation is not a suitable option. Although ABI has its advantages in those populations, most often, ABI is not recommended or accepted by the patients because of its limitations and shortcoming such as open-set word recognition in auditory mode, limited infrastructures for carrying out ABI surgery, and the high cost of implantation. This review highlights the benefits in non-tumor patients with ABI surgery and possible reasons for the limited acceptance of the ABI device from an Indian perspective.

Hearing and language development in children with brainstem implants: a systematic review

OBJECTIVE

To present scientific evidence, based on a systematic review of the literature, on the benefit of brainstem implants in auditory rehabilitation and language development in children.

METHODS

A systematic search was used to identify studies that contain information about the benefit of brainstem implants in the auditory rehabilitation and language development of children. The review was conducted based on a structured literature search, following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) checklist. The search was carried out in the PubMed, Web of Science and Scopus databases, using the combination "Auditory brainstem implants" AND "Pediatric", without restriction of language, period, and location. The quality assessment of the articles was performed using the Study Quality Assessment Tools.

RESULTS

Regarding hearing, children with brainstem implants showed sound detection, access to most speech sounds, basic auditory perception skills, recognition of ambient sounds, recognition of some frequently used words and phrases, in addition to some closed-set word discrimination capability. Expressive and comprehensive language were identified in children using auditory brainstem implants, increasing significantly in the short and long terms in most cases; however, in some of the children, such skills remained stable.

CONCLUSION

The auditory brainstem implant can be considered an effective alternative for children with cochlear malformation and/or auditory nerve deficiency and for those who cannot benefit from cochlear implant surgery.

Cochlear implantation versus auditory brainstem implantation in children with auditory nerve deficiencies

BACKGROUND

Cochlear nerve deficiency is one of the known causes of congenital sensorineural hearing loss. Management of hearing loss in children with cochlear nerve deficiency poses a multidimensional challenge. The absent or hypoplastic cochlear nerve may prevent electrical stimulation from reaching the brainstem and the auditory cortex. A deficient cochlear nerve can be associated with other inner ear malformations, which may diminish the success of cochlear implantation in those children. Promising results in adults after auditory brainstem implantation led to the expansion of candidacy to include the pediatric populations who were contraindicated for CIs.

OBJECTIVE

To review the outcomes of cochlear implantation versus that of auditory brainstem implantation in children with various conditions of the auditory nerve.

METHODS

This retrospective chart review study comprised two pediatric groups. The first group consisted of seven ABI recipients with cochlear nerve aplasia and the second group consisted of another seven children with cochlear nerve deficiencies who underwent CI surgery. The participants' auditory skills and speech outcomes were assessed using different tests selected from the Evaluation of Auditory Responses to Speech (EARS) test battery.

RESULTS

There were some individual variations in outcomes depending on the status of the auditory nerve. The mean CAP score of the ABI group was 2.87, while the mean SIR score was 0.62. On the other hand, the mean CAP score of the CI group was 1.29, while the mean SIR score was 0.42.

CONCLUSION

Our results are in good agreement with the reported auditory perception and speech and language development outcomes of pediatric auditory brainstem implantation. We added to the growing body of literature on the importance of verifying and identifying the status of the cochlear nerve in the decision-making process of the surgical management of those pediatric groups.

ABI-auditory brainstem implant

The Auditory Brainstem Implant (ABI) is based on the classic cochlear implant (CI) but uses a different stimulation electrode. At MED-EL, the early development activities on ABI started in the year 1994, with the suggestion coming from J. Helms and J. Müller from Würzburg, Germany in collaboration with the Univ. of Innsbruck Austria. The first ABI surgery in a neuro-fibromatosis (NF2) patient with the MED-EL device took place in the year 1997. Later, the indication of ABI was expanded to non-NF2 patients with severe inner-ear malformation, for whom a regular CI will not be beneficial. Key translational research activities at MED-EL in collaboration with numerous clinics investigating the factors that affect the hearing performance amongst ABI patients, importance of early ABI implantation in children, tools in pre-operative assessment of ABI candidates and new concepts that were pursued with the MED-EL ABI device. The CE-mark for the MED-EL ABI to be used in adults and children down to the age of 12 months without NF-2 was granted in 2017 mainly based on two long-term clinical studies in the pediatric population. This article covers the milestones of translational research from the first concept to the widespread clinical use of ABI in association with MED-EL.