MED-EL Combi40+ cochlear implantation in adults

OBJECTIVE/HYPOTHESIS: Cochlear implantation is currently the treatment of choice for severe to profound sensorineural hearing loss. The MED-EL Combi40+ (Innsbruck, Austria) cochlear implant system was approved for use in the United States in 2001. This device employs a 31-mm-long electrode array, ceramic case, and continuous interleaved sampling with Hilbert transformation for envelope extraction. A single institution's experience with the Combi40+ implant in adult patients was reviewed. STUDY DESIGN: Retrospective chart review. METHODS: Medical-surgical and audiological data were collected from 112 patients who received a MED-EL Combi40+ cochlear implant between December 1998 and April 2004. RESULTS: The rate of surgical complications and speech perception testing results compared favorably with those of other cochlear implant systems. For postlingually deafened adults, mean CNC word, HINTQ, CUNY, and HINT + 10 dB signal-to-noise ratio scores after 1 year of implant usage were 54%, 87%, 96%, and 64%, respectively. Prelingually deafened adults also derived significant benefit, but plateau performance for these patients was well below that for patients with later onset of deafness and significant variability was seen in this group. Repeat implantation for suspected device malfunction was undertaken in seven cases (6% of devices) (mean duration of use, 28 +/- 12 mo) with ultimate resolution of the presenting problem. CONCLUSION: The study results support the safety and efficacy of cochlear implantation with the MED-EL Combi40+ cochlear implant system.     

Technical Note: minimal access surgery for cochlear implantation with MED-EL devices

BACKGROUND: Minimally invasive techniques have been described for cochlear implant surgery, but so far this had not been the case for Med-EL devices. OBJECTIVE: To describe a newly developed minimal access approach for the implantation of Med-EL devices and report our results after up to 1 year of follow-up in 52 patients. DISCUSSION: The use of a minimally invasive approach without raising a flap or extensive drilling of a bony well was feasible in all 52 patients of this series. It shortened the surgical time to an average of 45 min and there were no specific postoperative complications. The average follow-up of 8.4 months was uneventful with the implants well covered and fixed in their position. The described approach therefore appears to be a safe, time- and cost-effective alternative to the standard procedure in cochlear implant surgery using Med-EL devices.     

Willingness-to-pay for pediatric cochlear implantation

OBJECTIVE: This paper presents the results of the first willingness-to-pay (WTP) study to be undertaken on cochlear implantation. It aims to measure the values parents place on the UK having a pediatric cochlear implantation (PCI) programme. METHODS: Face-to-face semi-structured interviews were conducted with parents of children from the Nottingham Pediatric Cochlear Implant programme, whom had been implanted for a period ranging from 1 month to 13 years. Parents willingness-to-pay for the UK to have a pediatric cochlear implantation programme were elicited using a bidding process question format and via a discrete choice question. To see if income was a significant determinant of willingness-to-pay an analysis of variance (ANOVA) was undertaken in the statistical package SPSS version 10. RESULTS: Two hundred and sixteen parents were interviewed over the period July 2001-August 2002, representing over 130h of interviewing. The mean and median willingness-to-pay values elicited were UK pound 127 and 50 per month, respectively (UK pound 2001/2002). Willingness-to-pay was positively related to income (P<0.020). When the income constraint was removed, 99% of parents choose the implant over having the money the implant would cost to spend in some other way to benefit their child. CONCLUSIONS: Parents of implanted children were willing to pay substantial monthly amounts for pediatric cochlear implantation. Most parents saw no alternative to pediatric cochlear implantation that could improve their child's quality of life to the same extent. Willingness-to-pay was sensitive to income as expected suggesting that the values elicited are both valid and influenced by a respondent's budget constraint.     

Comparing eSRT and eCAP measurements in pediatric MED-EL cochlear implant users

Introduction: Electrically evoked compound action potentials (eCAP) and electrically evoked stapedius reflexes are the most frequently used objective measurements for programming a cochlear implant (CI) audio processor. Objective methods are particularly beneficial for children and CI users that encounter difficulties in providing feedback. In this study, we compared the threshold and the slope of the eCAP amplitude growth function with the electrically evoked stapedius reflex threshold (eSRT) in pediatric CI users. Furthermore, the duration times required to perform eCAP and eSRT recordings were compared.

Methods: During a regular fitting session, 52 pediatric CI users with recordable eSRTs having MED-EL devices (MED-EL GmbH, Innsbruck, Austria) were programmed using the eSRT fitting method. The eCAP thresholds and the slopes of the amplitude growth function were measured across one apical, one medial, and one basal electrode contact.

Results: There was a weak to medium correlation between eCAP thresholds and eSRTs. The eCAP threshold profile did not correlate with the eSRT profile. Typically ECAP thresholds were at a lower stimulation charge than eSRTs with only 4/152 being higher. An eCAP threshold was found on 152/156 electrode contacts with eSRTs. On average, the eCAP measurements took 4.2 times longer to record per electrode than eSRT measurements (median durations 35?s vs. 120?s).

Conclusion: eSRTs were significantly higher than eCAP thresholds and eSRT and eCAP profiles were generally different from each other reducing the clinical relevance of eCAP testing for setting MCLs across the array. Additionally, the eSRT measurements were faster to record than the eCAP threshold and slope determination measurements.     

Complications of pediatric cochlear implantation

Cochlear implantation has been established as a method of auditory rehabilitation for selected deaf children. However, as with any surgical procedure, complications can occur and may be particularly devastating in children. In this retrospective study, complications encountered in 100 consecutive cochlear implant surgeries in children were analyzed. Surgical problems were limited to one case of delayed, transient facial paresis and one cerebrospinal fluid gusher. These findings demonstrate that cochlear implantation can be performed safely with careful preoperative planning and meticulous surgical technique.Presented at the Meeting of the Middle Section of the American Laryngological, Rhinological and Otological Society, Omaha, Nebraska, 21 January 1995     

Development of a communicative performance scale for pediatric cochlear implantation

OBJECTIVE: Verbal communicative competence is the main objective after early cochlear implantation in deaf children. However, there are currently no validated instruments to assess a child's real-world communicative abilities. We adopted a rigorous methodological approach to systematically develop the Functioning after Pediatric Cochlear Implantation instrument (FAPCI), a family-centered communicative performance scale based on a conceptual model of functioning established by the World Health Organization. DESIGN: Qualitative instrument development was based on a systematic review of the literature, focus groups, and semistructured interviews with the parents of 2- to 5-yr-old children with cochlear implants and deafness experts. Further refinement and testing of the psychometric validity of the draft instrument was conducted using factor analysis and a cross-sectional sample of 75 parents of children with cochlear implants. Nonparametric and parametric regressions were then performed to investigate the association of FAPCI scores with duration of cochlear implant use to provide preliminary evidence for the instrument's nomological validity. RESULTS: The final 23-item, parent-proxy FAPCI instrument represents a unidimensional scale of the real-world communicative performance of 2- to 5-yr-old children with cochlear implants. The scale demonstrated excellent reliability (Cronbach's alpha >or=0.86), and there was strong evidence supporting the instrument's nomological validity. FAPCI scores were positively associated with duration of implant use (p < .001), and 4 yr of implant use were required before maximal FAPCI scores were achieved. CONCLUSIONS: Verbal communication is a critical developmental domain that allows for optimal future emotional, cognitive, and behavioral growth. The FAPCI instrument is the first validated instrument ever designed to assess real-world communicative performance of a child with a cochlear implant. The systematic approach taken to development may enable FAPCI to be sensitive to other communication-related disorders commonly seen in childhood or to serve as a model for the development of other disorder-specific instruments.     

Barriers to early pediatric cochlear implantation

Objectives

Universal newborn hearing screening has significantly improved the ability to identify patients with congenital sensorineural hearing loss (SNHL), which results in earlier treatment and better hearing and development outcomes. It is recommended that patients born with SNHL who meet criteria receive cochlear implants (CIs) by a target age of 12 months, however many children are being implanted at an older age. This study aims to describe populations of pre-lingual patients with SNHL that are at risk for delayed implantation and to identify and analyze barriers that cause this delay.

Methods

Charts of patients receiving a CI between January 2008 and June 2012 at a tertiary care cochlear implant center were reviewed retrospectively. We looked at patient demographics, age at hearing loss diagnosis, age at implantation, and etiology of hearing loss. Barriers to implantation were identified through surveys completed by team members.

Results

Fifty-seven CI recipients were identified of which 42 were in patients with pre-lingual SNHL. SNHL etiology included: cochlear dysplasia (18%), GJB2/GJB6 (17%), acquired (10%) extreme prematurity (9%), and idiopathic (46%). The median age of SNHL diagnosis for pre-lingual patients was 15 months. Compared to private insurance, public insurance status was associated with SNHL diagnosis at a significantly later median age (20.0 vs. 4.0 months, p = 0.024), and with a significantly longer median interval from diagnosis to implantation (25.5 vs. 11.0 months, p = 0.029). While cochlear implant team members identified delayed insurance approval and medical comorbidities as reasons for delayed implantation, the most significant factor identified was parental, with delayed/missed appointments or reluctance for evaluations or surgery.

Conclusion

52% of patients with pre-lingual SNHL that met criteria for CI were implanted more than 12 months after diagnosis. Having public or no insurance was significantly associated with delayed implantation. Parental barriers were most common factors cited for delays in implantation. Overcoming these delays necessitates appropriate identification of at risk patients and creating a system to educate families and chaperone them through the process.     

A cost-utility analysis of pediatric cochlear implantation

OBJECTIVE/HYPOTHESIS: The aim of this study was to explore the cost-utility of pediatric cochlear implantation, incorporating savings associated with education into the analysis. METHODS: The costs of pediatric cochlear implantation were based on the full costs levied to purchasers, inclusive of complications and maintenance, by a large pediatric cochlear implant program in the United Kingdom. After implantation, profoundly hearing-impaired children have been found to develop hearing threshold levels equivalent to severely hearing-impaired children who wear hearing aids. An independent study calculated the educational costs for severely hearing-impaired and profoundly hearing-impaired children. From this study, savings in educational costs that would result from enabling the profoundly hearing-impaired to function as severely hearing-impaired were determined. Cost-utility was established conservatively by applying to children the known gains in utility reported by adults with cochlear implants. RESULTS: The discounted costs of creating a pediatric cochlear implant user and of maintaining the child over the first 12 years were 48,757 pound silver($78,011). The discounted difference in education costs associated with a profoundly hearing-impaired child (HL >95 dB) as compared with a severely hearing-impaired child (HL 70-95 dB) over the same period was 26,781 pound silver($42,850). These represent the potential savings in educational costs associated with pediatric cochlear implantation. Assuming implantation at age 4 years, the discounted net average cost of pediatric cochlear implantation over compulsory school years (ages 4-16) was 21,976 pound silver ($35,162). Cochlear implants have been shown to improve the quality of life in adults by 0.23 points per annum (where quality of life is rated on a scale from 0 to 1). Applying this weight to children receiving implantation at age 4 years, and assuming a life expectancy of 74 years, the quality-adjusted life-year (QALY) gain is calculated to be 16.33. The cost per undiscounted QALY gain was estimated to be 1,345.70 pound silver ($2153.12) and per discounted QALY gain to be 10,341 pound silver ($16,545.60). CONCLUSION: This study provides evidence, based on conservative assumptions, to support the view that pediatric cochlear implantation is a cost-effective health care intervention in profoundly hearing-impaired young children.     

Age at implantation: its importance in pediatric cochlear implantation

OBJECTIVE: To assess the influence of age at implantation on speech perception and speech intelligibility following pediatric cochlear implantation. STUDY DESIGN: A prospective study was undertaken on a consecutive group of 126 congenital and prelingually deaf children up to 4 years after implantation. The study group was confined to prelingually deaf children less than 7 years of age at the time of implantation. All had implantation with the same multichannel cochlear implant system. No child was lost to follow-up, and there were no exclusions from the study. METHODS: The Iowa Matrix Closed Set Sentence test, connected discourse tracking, categories of auditory performance, and speech intelligibility rating were used to assess the speech perception (closed and open set) and speech intelligibility of the children with implants. Regression analysis and Spearman rank correlation coefficients were used to assess the correlation between the outcome measures with age at implantation. The setting was a tertiary referral pediatric cochlear implant center in the United Kingdom. RESULTS: Age at implantation positively correlated with preimplantation assessment performance and with most of the outcome measures up to 24 months following implantation. However, at the 3-and 4-year intervals following implantation, age at implantation was found to be a strong negative predictor of all the outcomes studied (correlation coefficients ranging from -0.44 to -0.58, all statistically significant [P<.05]). CONCLUSIONS: The results of the present study provide strong evidence that prelingually deaf children should receive implants as early as possible to facilitate the later development of speech perception skills and speech intelligibility and thus maximize the health gain from the intervention. However, because of the wide variation in individual outcomes, age alone should not be used as a criterion to decide implant candidacy.     

The role of age in pediatric cochlear implantation

OBJECTIVE: To document progress, benefit and importance of age in paediatric cochlear implantation. DESIGN: The EARS (Evaluation of Auditory Responses to Speech) test battery was performed on 33 prelingually deaf children at regular intervals up to 36 months following implantation. All children participated in individually tailored intensive audiological rehabilitation programs after receiving their implants. In this respect, it was attempted to evaluate speech perception scores in children implanted before and after the age of 3 in a homogenous group. RESULTS: All children demonstrated encouraging improvements over time in their speech recognition abilities. Furthermore, it was observed that the children who were implanted under the age of 3 achieved higher levels of speech perception performance. CONCLUSION: In order to shorten the process of central maturation of the auditory system, it is desirable to implant the children as young as possible. Early intervention seems to be the ideal strategy in enabling prelingually deaf children to derive maximum benefit from cochlear implantation.     

儿童人工耳蜗手术的并发症与处理

通过复习国内外文献、内部交流及根据我院临床病例经验，回顾、总结儿童人工耳蜗手术常见并发症的发病率、临床表现、诊断和处理方法，其中包括国内外有关手术并发症的最新进展。本文着重讨论的是临床经常遇到而且较难处理的并发症，包括皮瓣感染及坏死，植入体硅橡胶过敏，面神经损伤，面神经刺激和开机后无听性反应等。认真做好术前诊断，完善手术细节，提高手术经验，手术并发症是可以避免和减少的。     

Revision pediatric cochlear implantation in a large tertiary center since 1986

Objective: To identify the rate of cochlear implantation (CI) re-implantation and assess audiologic outcomes.

Methods: Demographic, audiometric, radiographic, and clinical data were collected from the medical records of the first 834 pediatric patients (age < 18) who underwent CI at a tertiary-care center.

Results: Reviewing the first 834 pediatric patients who underwent CI between 1986 and 2013, 33 (4%) children have required re-implantation. Seven (0.8%) of these required a second re-implantation, for a total of 40 total revision surgeries (4.8%) and 21.1% of patients who underwent revision required multiple re-implantations. The mean age at initial CI was 3.5 years old, with identification of the failure an average of 2.7 years later (range, 0.1–10.1 years). The most common indications for re-implantation CI were unknown etiology (58%), vendor recall (18%), and trauma (9%). Twenty-three (88.5%) of the 26 patients who underwent only one re-implantation surgery achieved a complete insertion with both procedures. Eleven (91.7%) of 12 patients who had open set speech after their initial procedure maintained this after re-implantation surgery. Eight (38.1%) of 21 patients who did not have open-set speech after their initial implantation achieved open set speech with CI re-implantation.

Conclusion: CI re-implantation is not common in the pediatric population. However, given the time-sensitive nature of speech/language development in children, with the right indications, CI re-implantation can be performed safely without compromising audiologic outcomes. However, re-implanted patients have an increased risk they will require re-implantation again in the future.