Cochlear implants in children

Acute mastoiditis in cochlear implanted children: A single-centre experience

BACKGROUND

Acute mastoiditis (AM) is the most common complication of acute otitis media and primarily affects children under the age of two; current data on its prevalence in paediatric patients with cochlear implant (CI) are still scant. Proper management of AM in CI children is crucial in order to avoid the implications (financial and emotional) of an explant. Aim of this paper is to describe the cases of AM occurred among young patients with CI in follow up at our department, also in order to evaluate its prevalence, potential predisposing factors, clinical course and therapeutic strategies.

PATIENTS AND METHODS

Retrospective study. Medical records of all paediatric patients with CI, who had at least one year of follow-up, were searched aiming to identify those who developed AM, from January 1st 2002 to January 31st 2022. The following data were collected and analysed: demographic features, implant type and side, interval between CI surgery and AM, treatment, laboratory tests, clinical course, vaccination history, associated diseases.

RESULTS

AM was developed by six (1.3%) of the 439 children with CI (541 implanted ears). In total, 9 episodes (2.05 %) were recorded, as three patients reported two consecutive infections. Average time interval between CI surgery, to the first or only AM diagnosis, was 13.8 months (range 3-30 months). Furthermore, 3/6 of patients had a history of recurrent acute otitis media; 2/6 an autism spectrum disorder, associated to a combined immune deficiency in one case. All patients were hospitalized and promptly treated by intravenous antibiotic therapy; 4/6 also underwent a mastoidectomy. CI was not explanted in any cases of this series.

CONCLUSIONS

Over a 20-year period, AM rate in CI children was 1.3%, which is consistent with the current literature rates of 1-4.7%. All cases were successfully treated, preserving the integrity of the device. In our experience, the early parenteral antibiotic therapy and, when necessary, surgical treatment were adequate to eradicate the infection.

Age and Incidence of Cochlear Implantation in the Pediatric Population With Congenital Bilateral Profound Hearing Loss

OBJECTIVES

The current study characterizes age and incidence of cochlear implantation among qualifying children with congenital bilateral profound hearing loss in the U.S.

STUDY DESIGN

Deidentified cochlear implantation data were acquired from prospectively collected patient registries from two cochlear implant (CI) manufacturers (Cochlear Americas and Advanced Bionics). Children <36 months old were assumed to have congenital bilateral profound sensorineural hearing loss.

SETTING

U.S. CI centers.

PATIENTS

Children <36 months old who received CIs.

INTERVENTIONS

Cochlear implantation.

MAIN OUTCOME MEASURES

Age at implantation and incidence.

RESULTS

A total of 4,236 children <36 months old underwent cochlear implantation from 2015 to 2019. The median age at implantation was 16 months (interquartile range, 12-24 mo) and did not change significantly during the 5-year study period (p = 0.09). Patients residing closer to CI centers (p = 0.03) and treated at higher-volume centers (p = 0.008) underwent implantation at a younger age. Bilateral simultaneous implantation increased from 38% to 53% of CI surgeries in 2015 and 2019, respectively. Children who received bilateral simultaneous CIs were younger compared with those receiving unilateral or bilateral sequential CIs (median, 14 versus 18 mo; p < 0.001). The incidence of cochlear implantation increased from 7,648 per 100,000 person-years in 2015 to 9,344 in 2019 (p < 0.001).

CONCLUSION

Although the incidence of pediatric CI recipients and the frequency of bilateral simultaneous implantation increased over the study period, age at implantation did not change significantly and far exceeded current Food and Drug Administration (9 mo) and American Academy of Otolaryngology and Head and Neck Surgery position statement (6-12 mo) guidelines.

Longitudinal outcomes for educational placement and quality of life in a prospectively recruited multinational cohort of children with cochlear implants

OBJECTIVES

The aim of this study was to report on the educational placement, quality of life and speech reception changes in a prospectively recruited group of children after they received a cochlear implant (CI).

METHOD

Data was collected on 1085 CI recipients of as part of a prospective, longitudinal, observational, international, multi-centre, paediatric registry, initiated by Cochlear Ltd (Sydney, NSW, Australia). Outcome data from children (≤10 years old) implanted in routine practice was voluntarily entered into a central, externally hosted, e-platform. Collection occurred prior to initial device activation (baseline) and at six monthly follow-up intervals up to 24 months and then at 3 years post activation. Clinician reported baseline and follow up questionnaires and Categories of Auditory Performance version II (CAP-II) outcomes were collated. Self-reported evaluation forms and patient information were provided by the parent/caregiver/patient via the implant recipient baseline and follow up, Children Using Hearing Implants Quality of Life (CuHIQoL) and Speech Spatial Qualities (SSQ-P) Parents Version questionnaires.

RESULTS

Children were mainly bilaterally profoundly deaf, unilaterally implanted and used a contralateral hearing aid. Prior to implant 60% used signing or total communication as their main mode of communication. Mean age at implant was 3.2 ± 2.2 years (range 0-10 years). At baseline 8.6% were in mainstream education with no additional support and 82% had not yet entered school. After three years of implant use, 52% had entered mainstream education with no additional support and 38% had not yet entered school. In the sub-group of 141 children who were implanted at or after three years of age and were thus old enough to be in mainstream school at the three-year follow up, an even higher proportion (73%) were in mainstream education with no support. Quality of life scores for the child improved statistically significantly post implant compared to baseline and continued to improve significantly at each interval up to 3 years (p < 0.001). Parental expectation scores reduced statistically significantly from baseline compared to all intervals (p < 0.028) and then increased significantly at 3 years compared to all post baseline follow-up intervals (p < 0.006). The impact on family life was reduced post implant compared to baseline and continued to reduce between annual intervals (p < 0.001). At three years post follow up median CAP II scores were 7 (IQR 6-7) and mean SSQ-P scores were 6.8 (SD1.9) 6.0 (SD1.9) and 7.4 (SD 2.3) for speech spatial and qualities scales respectively. SSQ-P and CAP II scores improved statistically and clinically significantly compared to baseline by one year post implantation. CAP II scores continued to improve at each test interval up to three years post implant. Speech and Qualities scores improved significantly between years 1 and 2 (p < 0.001), but only the Speech scores improved significantly between years 2 and 3 (p = 0.004).

CONCLUSIONS

Mainstream educational placement was achievable for most of the children, including those implanted at an older age. Quality of life for the child and the wider family improved. Future research could focus on the impact of mainstream school placement on children's academic progress, including measures of academic attainment and social functioning.

From Bench to Booth: Examining Hair-Cell Regeneration Through an Audiologist's Scope

Damage to auditory hair cells is a key feature of sensorineural hearing loss due to aging, noise exposure, or ototoxic drugs. Though hair-cell loss is permanent in humans, research in bird species led to the discovery that analogous hair cells of the avian basilar papilla are able to regenerate after being damaged by ototoxic agents. Regeneration appears to occur through a combination of the mitotic expansion of a precursor population of supporting cells and direct transdifferentiation of supporting cells into functioning hair cells. This review will synthesize the relevant anatomy and pathophysiology of sensorineural hearing loss, the historical observations that led to the genesis of the hair-cell regeneration field, and perspectives on initial human hair-cell regeneration trials.

Prevalence of Surgical, Anesthetic, and Device-related Complications Among Infants Implanted Before 9 and 12 Months of Age Versus Older Children: Evidence for the Continued Expansion of Pediatric Cochlear Implant Candidacy Criteria

OBJECTIVE

To compare the prevalence of surgical, anesthetic, and device-related complications among infants and older children receiving cochlear implantation (CI).

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary academic referral center.

PATIENTS

Pediatric patients who underwent CI from November 1990 to January 2020.

INTERVENTION

CI.

MAIN OUTCOME MEASURES

Surgical, anesthetic, and device-related complication rates were compared by age group (<12 versus 12-23 versus 24+ months with subset analysis of <9 versus 9-11 months).

RESULTS

A total of 406 primary pediatric CI surgeries encompassing 482 ears were analyzed, including 45 ears in 23 patients implanted less than 9 months and 89 ears in 49 patients less than 12 months. No anesthetic complications occurred. Postoperative surgical and device-related complication rates were not significantly different among the less than 12, 12 to 23, and 24+ month groups (16% versus 16% versus 12%; p = 0.23) or between the less than 9 and 9 to 11 month groups (22% versus 9%; p = 0.09). Thirty-day readmission was significantly higher for patients less than 12 months compared with patients 24+ months (6% versus <1%; p = 0.011), but was not significantly higher compared with patients 12 to 23 months (6% versus 3%; p = 0.65). Reoperation rates did not differ significantly among the less than 12, 12 to 23, and 24+ month groups (10% versus 7% versus 6%; p = 0.31).

CONCLUSIONS

The prevalence of surgical, anesthetic, and device related complications was not significantly different among infants implanted less than 9 or less than 12 months of age when compared with older children. These data provide evidence for the continued expansion of pediatric cochlear implant candidacy criteria to include appropriately selected infants less than 9 months of age.

Achieving optimal vaccine administration in a pediatric cochlear implant program after implementation of a Quality Improvement Project

OBJECTIVES

To maximize vaccination compliance in children undergoing cochlear implantation and thus minimize meningitis-related complications. To present a Quality Improvement (QI) Project for 23-valent pneumococcal polysaccharide vaccine (PPSV-23) administration within a pediatric cochlear implant program.

METHODS

We identified children from birth through 21 years of age with cochlear implants or cochlear implant candidates who were seen at Children's Health Medical Center/UT Southwestern Medical Center, Dallas between 12/2018 and 01/2020. Protocols were developed for physicians and nurses using electronic medical record (EMR) smart phrases with prompts to review and document vaccine status and plan. Charts were reviewed for six consecutive cycles of 6-12 weeks for vaccine documentation and plan compliance. Regular feedback was provided to physicians and nurses. A cochlear implant EMR registry was developed for increased surveillance of vaccine administration.

RESULTS

Physicians and nurses showed an improvement in vaccine documentation from the start of the project to the first data cycle review (61%-90% and 20%-91% for physicians and nurses respectively). This was followed by a regression in the third to fourth review cycles (decrease to 67% and 80% compliance). Vaccine documentation compliance improved after subsequent review and feedback, and peaked during the final cycle of the review (83% and 100% compliance). During the year-long QI project, one child with a cochlear implant missed the PPSV-23 vaccine but was identified during cycle review and vaccinated. This occurred during the third cycle, and for the remaining three cycles there were no missed vaccinations. On completion of the QI project, a formal vaccination oversight program was introduced with a physician/nurse team that reviews the cochlear implant EMR registry monthly for children who have not been vaccinated. In the 13 months since the completion of the QI project there has been 100% compliance with no children who missed vaccination.

CONCLUSION

We present a vaccination program with oversight to address missed vaccinations. Implementation of a QI project followed by transition to a formal vaccination oversight program eliminated missed PPSV-23 vaccinations in children with cochlear implants. We recommend that cochlear implant programs use similar approaches to ultimately minimize potential meningitis-related complications in patients with cochlear implants.

Language and Audiological Outcomes Among Infants Implanted Before 9 and 12 Months of Age Versus Older Children: A Continuum of Benefit Associated With Cochlear Implantation at Successively Younger Ages

OBJECTIVE

To compare language and audiological outcomes among infants (<9 and <12 mo) and older children receiving cochlear implantation (CI).

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary academic referral center.

PATIENTS

Pediatric patients receiving CI between October 1995 and October 2019.

INTERVENTION

Cochlear implantation.

MAIN OUTCOME MEASURES

Most recent language and audiological assessment scores were evaluated by age group.

RESULTS

A total of 118 children were studied, including 19 who were implanted <9 months of age, 19 implanted 9 to <12 months of age, and 80 implanted 12 to <36 months of age. The mean duration of follow-up was 7.4 ± 5.0 years. Most recent REEL-3 receptive (88 ± 12 vs. 73 ± 15; p = 0.020) and expressive (95 ± 13 vs. 79 ± 12; p = 0.013) communication scores were significantly higher in the <9 months group compared to the 9 to <12 months group. PLS and OWLS auditory comprehension and oral expression scores were significantly higher in the <12 months group compared to the 12 to <36 months group. The difference in NU-CHIPS scores between <12 and 12 to <36 months was statistically significant (89% ± 6 vs. 83% ± 12; p = 0.009). LNT scores differed significantly between <9 and 9 to <12 months (94% ± 4 vs. 86% ± 10; p = 0.028).

CONCLUSIONS

The recent FDA expansion of pediatric CI eligibility criteria to include infants as young as 9 months of age should not serve as a strict clinical cutoff. Rather, CI can be pursued in appropriately selected younger infants to optimize language and audiological outcomes.

Molecular investigation in children candidates and submitted to cochlear implantation

Aim

recent progresses in molecular biology have been made in the diagnosis of sensorineural hearing loss. The high prevalence of a connexin 26 gene mutation, and its easy identification have made the diagnosis possible. The most frequent gene mutation is called 35delG. The purpose of this study was to evaluate the prevalence of 35delG mutation in children submitted to cochlear implantation who had severe and profound hearing loss previously diagnosed as idiopathic.

Method

The study was done at the Cochlear Implantation Clinic of the Otolaryngology Department and at the Laboratório Genética Humana-CBMEG, UNICAMP-SP. 32 children with severe to profound sensorineural hearing loss were evaluated. The detection of the 35delG mutation was made by a allele - specific PCR, using primers and polymerase chain reaction.

Results

69% had a normal exam, 12% were homozygous for the mutation, 19% of the cases were heterozygous. The 35delG mutation in heterozygousity is not a cause of hearing loss.

Conclusion

The data confirm the high prevalence of the 35delG mutation in nonsyndromic bilateral profound sensorineural hearing loss. It was also possible to diagnose the cause of hearing loss as genetic in a significant percentage of patients. That stresses the importance of the molecular investigation in those cases formerly classified as idiopathic.

Longitudinal improvements in communication and socialization of deaf children with cochlear implants and hearing aids: evidence from parental reports

BACKGROUND

Research has shown that the cochlear implant may improve deaf children's speech and communication skills. However, little is known about its effect on children's ability to socialize with hearing peers.

METHODS

Using a standardized psychological measure completed by parents and a longitudinal design, this study examined the development of communication, socialization, and daily living skills of children who used hearing aids or cochlear implants for an average of 11 and 6 years, respectively.

RESULTS

Results show that children with cochlear implants, who were more delayed than children with hearing aids at the outset, made significant progress over time. Children with both devices achieved age-appropriate development after years of hearing aid or cochlear implant use.

CONCLUSIONS

The pattern of results suggests that cochlear implants may be effective in improving deaf children's communication and social skills.

Does exogenous GM1 ganglioside enhance the effects of electrical stimulation in ameliorating degeneration after neonatal deafness?

This study examined the combined effects of administration of exogenous GM1 ganglioside and electrical stimulation on the cochlear nucleus (CN) of cats deafened neonatally by ototoxic drugs. Five normal hearing adult cats served as controls. Another 12 cats were deafened bilaterally by daily injections of neomycin sulfate (60 mg/kg) for 17-21 days after birth until auditory brainstem testing demonstrated profound hearing loss. Six of the deaf animals comprised the GM1 group, which received daily injections of GM1 ganglioside (30 mg/kg) for 28-38 days during the period after profound deafness was confirmed, and prior to receiving a cochlear implant. The non-GM1 group (n=6) received no treatment during this interim period. All the deafened animals underwent unilateral cochlear implantation at 6-9 weeks postnatal and received several months (mean duration, 32 weeks) of chronic electrical stimulation (4 h/day, 5 days/week). Stimulation was delivered by intracochlear bipolar electrodes, using electrical signals that were designed to be temporally challenging to the central auditory system. Results showed that in the neonatally deafened animals, both the GM1 and non-GM1 groups, the volume of the CN was markedly reduced (to 76% of normal), but there was no difference between the animals that received GM1 and those that did not. The cross sectional areas of spherical cell somata in both GM1 and non-GM1 groups also showed a highly significant reduction in size, to < or =75% of normal after neonatal deafening. Moreover, in both the GM1 and non-GM1 groups, the spherical cells in the CN ipsilateral to the implanted cochlea were significantly larger (6%) than cells in the control, unstimulated CN. Again, however, there was no significant difference between the GM1 group and the non-GM1 group in spherical cell size. These results contrast sharply with previous reports that exogenous GM1 prevents CN degeneration after neonatal conductive hearing loss and partially prevents spiral ganglion cell degeneration when administered immediately after ototoxic drug deafening in adult animals. Taken together, findings to date suggest that GM1 may be effective in preventing degeneration only if the GM1 is administered immediately at the time hearing loss occurs.

Plasticity in central representations in the inferior colliculus induced by chronic single- vs. two-channel electrical stimulation by a cochlear implant after neonatal deafness

The goal of this research is to examine the functional consequences of patterned electrical stimulation delivered by a cochlear implant in the deafened developing auditory system. In previous electrophysiological experiments conducted in the inferior colliculus (IC), we have demonstrated that the precise cochleotopic organization of the central nucleus (ICC) develops normally in neonatally deafened unstimulated cats and is unaltered despite the lack of normal auditory input during development. However, these studies also showed that chronic electrical stimulation delivered at a single intracochlear location by one bipolar channel of a cochlear implant induces significant expansion of the central representation of the stimulated cochlear sector and degrades the cochleotopic organization of the IC. This report presents additional data from a new experimental series of neonatally deafened cats that received chronic stimulation on two adjacent bipolar intracochlear channels of a cochlear implant. Results suggest that competing inputs elicited by electrical stimulation delivered by two adjacent channels can maintain the selective representations of each activated cochlear sector within the central auditory system and prevent the expansion seen after single-channel stimulation. Alternating stimulation of two channels and use of highly controlled electrical signals may be particularly effective in maintaining or even sharpening selectivity of central representations of stimulated cochlear sectors. In contrast, simultaneous stimulation using two channels of a model analog cochlear implant processor in one experimental animal failed to maintain channel selectivity and resulted in marked expansion and fusion of the central representations of the stimulated channels. This potentially important preliminary result suggests that under some conditions the central auditory system may be unable to discriminate simultaneous, overlapping inputs from adjacent cochlear implant channels as distinct.