Comparison of Outcomes in Unilateral and Bilateral Pediatric Cochlear Implants: Our Experience

The aim of our study is to compare the outcomes in unilateral and bilateral cochlear implants in pediatric age and also between simultaneous and sequential cochlear implant surgery. This retrospective study was carried out with 83 children aged between 12 months to 2.5 years which included 41 children with bilateral Cochlear implants and 42 with unilateral implants. Out of these 41 children, 21 were simultaneous and 20 were sequential cochlear implant. All the children were operated at civil hospital Gandhinagar, Gujarat, India. CAP, SIR, localization, traffic noise and speech in noise scores were assessed at regular intervals over the period of 4 years. Also the drug administration time, surgical time, operating room time were assessed for simultaneous and sequential cochlear implant surgery. Children with bilateral simultaneous implants fared significantly better with CAP, SIR, localization, speech noise and traffic noise scores than sequential bilateral implants and unilateral implants with a significant difference of means t tests between the two groups. Simultaneous cochlear implant surgery is associated with reduced surgical time, operating room time, it shortens the total in patient stay. There is less of drug administration and bilateral ones are stimulated simultaneously. Bilateral cochlear implants perform better with respect to auditory perception skills and spontaneous speech when compared with unilateral implants, but simultaneous surgery is better and safe option for pediatric cochlear implantation.

Hearing and speech benefits of cochlear implantation in children: A review of the literature

Cochlear implantation is a safe and reliable treatment for children with severe to profound hearing loss. The primary benefit of these medical devices in children is the acquisition of hearing, which promotes development of spoken language. The present paper reviews published literature demonstrating predictive effects of a number of factors on acquisition of hearing development and speech recognition. Of the many variables that contribute to an individual child's development after implantation, age at implantation, the presence of medical comorbidities, social determinants of health, and the provision of bilateral versus unilateral hearing are those that can vary widely and have consistently shown clear impacts. Specifically, age of implantation is crucial to reduce effects of deafness on the developing auditory system and capture the remarkable plasticity of early development. Language development after cochlear implantation requires therapy emphasizing hearing and oral communication, education, and other support which can be influenced by known social determinants of health; specifically, outcomes in children decline with reductions in socioeconomic status and levels of parental education. Medical co-morbidities also slow rates of progress after cochlear implantation. On the other hand, benefits of implantation increase in children who are provided with access to hearing from both ears. In sum, cochlear implants promote development of hearing in children and the best outcomes are achieved by providing early access to sound in both ears. These benefits can be limited by known social determinants of health which restrict access to needed support and medical comorbidities which add further complexity in care and outcome.

Speech Production Quality of Cochlear Implant Users with Respect to Duration and Onset of Hearing Loss

PURPOSE

To assess whether postlingual onset and shorter duration of deafness before cochlear implant (CI) provision predict higher speech intelligibility results of CI users.

METHODS

For an objective judgement of speech intelligibility, we used an automatic speech recognition system computing the word recognition rate (WR) of 50 adult CI users and 50 age-matched control individuals. All subjects were recorded reading a standardized text. Subjects were divided into three groups: pre- or perilingual deafness (A), both >2 years before implantation, postlingual deafness <2 years before implantation (B), or postlingual deafness >2 years before implantation (C).

RESULTS

CI users with short duration of postlingual deafness (B) had a significantly higher WR (median 74%) than CI users with long duration of postlingual deafness (C; 68%, p < 0.001) or pre-/perilingual onset (A; 56%, p < 0.001). Compared to their control groups only CI users with short duration of postlingual deafness reached similar WR, others showed significantly lower WR. Other factors such as hearing loss onset, duration of CI use, or duration of amplified hearing showed no consistent influence on speech quality.

CONCLUSIONS

The speech production quality of adult CI users shows dependencies on the onset and duration of deafness. These features need to be considered while planning rehabilitation.

Bilateral cochlear implants in children: Effects of auditory experience and deprivation on auditory perception

Spatial hearing skills are essential for children as they grow, learn and play. These skills provide critical cues for determining the locations of sources in the environment, and enable segregation of important sounds, such as speech, from background maskers or interferers. Spatial hearing depends on availability of monaural cues and binaural cues. The latter result from integration of inputs arriving at the two ears from sounds that vary in location. The binaural system has exquisite mechanisms for capturing differences between the ears in both time of arrival and intensity. The major cues that are thus referred to as being vital for binaural hearing are: interaural differences in time (ITDs) and interaural differences in levels (ILDs). In children with normal hearing (NH), spatial hearing abilities are fairly well developed by age 4-5 years. In contrast, most children who are deaf and hear through cochlear implants (CIs) do not have an opportunity to experience normal, binaural acoustic hearing early in life. These children may function by having to utilize auditory cues that are degraded with regard to numerous stimulus features. In recent years there has been a notable increase in the number of children receiving bilateral CIs, and evidence suggests that while having two CIs helps them function better than when listening through a single CI, these children generally perform worse than their NH peers. This paper reviews some of the recent work on bilaterally implanted children. The focus is on measures of spatial hearing, including sound localization, release from masking for speech understanding in noise and binaural sensitivity using research processors. Data from behavioral and electrophysiological studies are included, with a focus on the recent work of the authors and their collaborators. The effects of auditory plasticity and deprivation on the emergence of binaural and spatial hearing are discussed along with evidence for reorganized processing from both behavioral and electrophysiological studies. The consequences of both unilateral and bilateral auditory deprivation during development suggest that the relevant set of issues is highly complex with regard to successes and the limitations experienced by children receiving bilateral cochlear implants. This article is part of a Special Issue entitled .

Cochlear implants in Belgium: Prevalence in paediatric and adult cochlear implantation

OBJECTIVES

Belgium, and especially the northern region called Flanders, has been a centre of expertise in cochlear implants and early hearing screening for many years. Cochlear implants are reimbursed by the Belgian National Institute for Health and Disability (BNIHD) Insurance in adults and in children since October 1994. More than 20 years later, we would like to measure the prevalence of cochlear implants in adults and in children till now.

MATERIALS AND METHODS

Based on scientific research data on the prevalence of severe to profound hearing loss in adults and in children and on the number of implantations from the data of the BNIHD, we could measure the percentages of paediatric and adult CI users in comparing to the number of CI candidates.

RESULTS

The degree of utilisation of cochlear implantation varies considerably between the paediatric and the adult population. On average, 78% of deaf children are receiving cochlear implants, but in adults only 6.6% of CI candidates are receiving one.

CONCLUSION

There are big differences in Belgium in utilisation of cochlear implants between adults and children. Because of the underutilisation of cochlear implants, especially in adults, we have to work on raising the general awareness of the benefits of cochlear implants, and its improvement in quality of life, based on cost-effectiveness data and on guidelines for good clinical practice.

Simultaneous bilateral cochlear implantation in a five-month-old child with Usher syndrome

OBJECTIVE

To report a rare case of simultaneous bilateral cochlear implantation in a five-month-old child with Usher syndrome.

METHOD

Case report.

RESULTS

A five-month-old boy with Usher syndrome and congenital profound bilateral deafness underwent simultaneous bilateral cochlear implantation. The decision to perform implantation in such a young child was based on his having a supportive family and the desire to foster his audiological development before his vision deteriorated. The subject experienced easily resolvable intra- and post-operative adverse events, and was first fitted with an externally worn audio processor four weeks after implantation. At 14 months of age, his audiological development was age-appropriate.

CONCLUSION

Simultaneous bilateral cochlear implantation is possible, and even advisable, in children as young as five months old when performed by an experienced implantation team.

Parental perspectives of children using cochlear implant

PURPOSE: To evaluate the parents' perspective with regard to evolution of their child with cochlear implant (CI). METHODS: This was a cross-sectional prospective study conducted at the Centro de Pesquisas Audiológicas of Hospital de Reabilitação de Anomalias Craniofaciais of Universidade de São Paulo. The selection of the sample was performed from the spontaneous demand, among the months from July to December 2011. The final sample comprised 50 parents or guardians of children using CI, with minimum 1 year and maximum of 3 years of device use. The translated and adapted to Brazilian Portuguese version of the questionnaire "Perspectives of parents of children with cochlear implants" was applied. This instrument consists of 74 questions and allows quantification of the parents' perspective on subscales that illustrate the situation of the child and family. Each question has five options scored from one to five responses. The Spearman test for comparison of results between the subscales was applied. RESULTS: The social relationships, self-sufficiency, and communication subscales showed the highest mean score, whereas the worst score was for child support subscale, reflecting the independence and autonomy of the patients. The correlation between the child subscales was realized, and the results showed themselves significant and positive for communication subscale of communication with all others subscales. The family subscales also had a positive correlation with the communication, education, and self-sufficiency. CONCLUSION: These results demonstrate that parents have good expectations regarding communication, independence, and social participation of children after CI surgery, and this questionnaire is a useful tool for use in clinical practice.

Accessibility to cochlear implants in Belgium: state of the art on selection, reimbursement, habilitation, and outcomes in children and adults

Belgium, and especially the northern region called Flanders, has been a center of expertise in cochlear implants and early hearing screening for many years. Some of their surgeons and engineers were pioneers in the development of cochlear implants and in 1998 Flanders was the first region in Europe to implement a universal hearing screening program for all neonates. The Belgian National Institute for Health and Disability Insurance has reimbursed cochlear implants in children and adults since 1994 and bilateral implantation in children under the age of 12 years since February 2010. These deaf children, screened and implanted early, achieve higher auditory, speech and language outcomes and increasing numbers are going to regular schools using fewer interpreters. In 2010, 93% of severe-to-profound deaf preschool children in Flanders had received cochlear implants and 25% had bilateral implants. Although on average twice as many adults as children are implanted a year in Belgium, we have less research data available from this adult population. Also very little is published about the growth curves and minimal rehabilitation requirements (intensity, duration etc.) after implantation for both children and adults. So, there still remain many challenges for the future.

Outcomes in cochlear implantation: variables affecting performance in adults and children

This article highlights variables that affect cochlear implant performance, emerging factors warranting consideration, and variables shown not to affect performance. Research on the outcomes following cochlear implantation has identified a wide spectrum of variables known to affect pos0timplantation performance. These variables relate to the device itself as well as individual patient characteristics. Factors believed to affect spiral ganglion cell survival and function have been shown to influence postoperative performance. Binaural hearing affects performance. Social and educational factors also affect postoperative performance. Novel variables capable of affecting performance continue to emerge with increased understanding of auditory pathway development and neural plasticity.

Cochlear implants: current status and future potential

This article reviews the current status of cochlear implantation in both adults and children, including expanding candidacy groups, bilateral implantation, advances in speech processing software, internal and external device hardware, surgical techniques and outcomes. Promising advances, novel therapies and evolving concepts are also highlighted in terms of their future impact on clinical outcomes.