Multicentric study on surgical information and early safety and performance results with the Bonebridge BCI 602: an active transcutaneous bone conduction hearing implant.

AIM: This European multicentric study aimed to prove safety and performance of the Bonebridge BCI 602 in children and adults suffering from either conductive hearing loss (CHL), mixed hearing loss (MHL), or single-sided sensorineural deafness (SSD). METHODS: 33 patients (13 adults and 10 children with either CHL or MHL and 10 patients with SSD) in three study groups were included. Patients were their own controls (single-subject repeated measures), comparing the unaided or pre-operative to the 3-month post-operative outcomes. Performance was evaluated by sound field thresholds (SF), word recognition scores (WRS) and/or speech reception thresholds in quiet (SRT) and in noise (SNR). Safety was demonstrated with a device-specific surgical questionnaire, adverse event reporting and stable pure-tone measurements. RESULTS: The Bonebridge BCI 602 significantly improved SF thresholds (+ 25.5 dB CHL/MHL/SSD), speech intelligibility in WRS (+ 68.0% CHL/MHL) and SRT in quiet (- 16.5 dB C/MHL) and in noise (- 3.51 dB SNR SSD). Air conduction (AC) and bone conduction (BC) thresholds remained stable over time. All adverse events were resolved, with none unanticipated. Mean audio processor wearing times in hours [h] per day for the CHL/MHL group were ~ 13 h for adults, ~ 11 h for paediatrics and ~ 6 h for the SSD group. The average surgical length was 57 min for the CHL/MHL group and 42 min for the SSD group. The versatility of the BCI 602 (reduced drilling depth and ability to bend the transition for optimal placement) allows for treatment of normal, pre-operated and malformed anatomies. All audiological endpoints were reached. CONCLUSIONS: The Bonebridge BCI 602 significantly improved hearing thresholds and speech understanding. Since implant placement follows the patient's anatomy instead of the shape of the device and the duration of surgery is shorter than with its predecessor, implantation is easier with the BCI 602. Performance and safety were proven for adults and children as well as for the CHL/MHL and SSD indications 3 months post-operatively.

Evaluating the effectiveness and reliability of the Vibrant Soundbridge and Bonebridge auditory implants in clinical practice: Study design and methods for a multi-centre longitudinal observational study.

BACKGROUND: The Vibrant Soundbridge middle ear implant and the Bonebridge bone conducting hearing device are hearing implants that use radio frequency transmission to send information from the sound processor to the internal transducer. This reduces the risk of skin problems and infection but requires a more involved surgical procedure than competitor skin penetrating devices. It is not known whether more complex surgery will lead to additional complications. There is little information available on the reliability of these systems and adverse medical or surgical events. The primary research question is to determine the reliability and complication rate for the Vibrant Soundbridge and Bonebridge. The secondary research question explores changes in quality of life following implantation of the devices. The tertiary research question looks at effectiveness via changes in auditory performance. METHOD: The study was designed based on a combination of a literature search, two clinician focus groups and expert review.A multi-centre longitudinal observational study was designed. There are three study groups, two will have been implanted prior to the start of the study and one group, the prospective group, will be implanted after initiation of the study. Outcomes are surgical questionnaires, measures of quality of life, user satisfaction and speech perception tests in quiet and in noise. CONCLUSION: This is the first multi-centre study to look at these interventions and includes follow up over time to understand effectiveness, reliability, quality of life and complications.

Balance in children following cochlear implantation.

OBJECTIVES: To assess the vestibular function of children who had unilateral and bilateral cochlear implants compared with a control group of otherwise healthy children who had not been implanted. STUDY DESIGN: Observational case-control study. METHODS: Posturography was carried out in the form of a Modified Clinical Test of Sensory Interaction on Balance using a Wii Balance Board and the Vestio App on an iPod Touch. Thirty children in total were tested, 10 children in each cohort. Results in the form of root mean square calculations were available for each child. RESULTS: Results showed a significant difference in the vestibular function of implanted children and the non-implanted control group (P < 0.05). As expected, children in all groups had more difficulty maintaining posture with their eyes closed on a compliant surface (P < 0.05). Thirty per cent of children with bilateral and 10% with unilateral cochlear implants were unable to complete testing. CONCLUSIONS: Our study demonstrates posturography as an inexpensive, easily operated tool that can be used to assess paediatric vestibular function. It showed a significant difference between the control group and the implanted groups. Further work prompted by this study will include interval post-operative testing to more accurately assess the effect that implantation has on vestibular function.

How we do it: Local anaesthetic cochlear implantation.

OBJECTIVES: To review a patient series of 16 cochlear implantations performed under local anaesthetic (LA), including a description of the centre's technique for this procedure. We also describe the application of a method for calculation of the potential morbidity/mortality avoided by using this technique. METHODS: Chart review of 16 patients' pre-operative medical and anaesthetic notes and calculation of predicted individual P-POSSUM Scores for operative morbidity/mortality. RESULTS: All 16 patients were implanted successfully with no significant complications. Age range was 26-92 years, with an average of 68 years. The patients' average predicted mortality score associated with a general anaesthetic (GA) was 8.6% and morbidity score was 58%. CONCLUSIONS: Our experience shows LA cochlear implantation to be a safe and effective procedure. It has the benefit of avoiding the operative mortality risk predicted by P-POSSUM Scores. Cochlear implantation is known to significantly improve quality of life for users. Our findings suggest a potential group of cochlear implant recipients considered 'unfit' for GA may be being denied access to this intervention or being exposed to additional risk.

Evaluation of bilaterally implanted adult subjects with the nucleus 24 cochlear implant system.

OBJECTIVE: To evaluate the speech perception benefits of bilateral implantation for subjects who already have one implant. STUDY DESIGN: Repeated measures. PATIENTS: Thirty adult cochlear implant users who received their second implant from 1 to 7 years with a mean of 3 years after their first device. Ages ranged from 29 to 82 years with a mean of 57 years. SETTING: Tertiary referral centers across the United Kingdom. MAIN OUTCOME MEASURES: Monosyllabic consonant-nucleus-consonant words and City University of New York sentences in quiet with coincident speech and noise and with the noise spatially separated from the speech by +/-90 degrees . RESULTS: At 9 months, results showed the second ear in noise was 13.9 +/- 5.9% worse than the first ear (p < 0.001); a significant binaural advantage of 12.6 +/- 5.4% (p < 0.001) over the first ear alone for speech and noise from the front; a 21 +/- 6% (p < 0.001) binaural advantage over the first ear alone when noise was ipsilateral to the first ear; no binaural advantage when noise was contralateral to the first ear. CONCLUSIONS: There is a significant bilateral advantage of adding a second ear for this group. We were unable to predict when the second ear would be the better performing ear, and by implanting both ears, we guarantee implanting the better ear. Sequential implantation with long delays between ears has resulted in poor second ear performance for some subjects and has limited the degree of bilateral benefit that can be obtained by these users. The dual microphone does not provide equivalent benefit to bilateral implants.

Auditory perception and speech discrimination after cochlear implantation in patients with connexin 26 (GJB2) gene-related deafness.

HYPOTHESIS: Auditory perception and speech discrimination among pediatric cochlear implantees may vary because of underlying deafness etiology, including connexin 26 (GJB2) gene-related deafness. BACKGROUND: Preliminary data suggest pathologic changes due to GJB2 mutations do not affect the spiral ganglion cells, which are stimulated by the cochlear implant. The survival of the spiral ganglion cells is believed to be an important determinant of outcome after surgery. Patients with GJB2-related deafness may therefore have enhanced prospects for good speech discrimination after implantation. METHODS: In an observational cohort study, GJB2 mutation analysis was performed using polymerase chain reaction amplification and direct sequencing on 31 prelingually deaf pediatric cochlear implantees, of which there were 30 with nonsyndromic deafness of unknown etiology, and one with keratitis-ichthyosis-deafness syndrome. Speech discrmination was assessed prospectively when they had reached postoperative year 3 using the IOWA Matrix Level B Sentences test and Glendonald Auditory Screening Procedure (GASP), with both patients and assessors blind to GJB2 status. RESULTS: Eleven patients had GJB2-related deafness and 20 patients had GJB2-unrelated deafness. IOWA Matrix scores were higher in patients with GJB2-related deafness but did not reach statistical significance. However, GASP scores were statistically significantly higher in patients with GJB2-related deafness (median word score, 92%; median sentence score, 80%), compared with those of patients with GJB2-unrelated deafness (median word score, 63%; median sentence score, 45%; word score, p = 0.037; sentence score, p = 0.045). Ordinal logistic regression analysis on IOWA Matrix and GASP sentence scores found better statistically significant scores in patients with GJB2-related deafness (p < 0.05) after adjustment for confounding variables. CONCLUSION: Pediatric cochlear implantees with GJB2-related deafness appear to have equal or better speech discrimination compared with a group of prelingually deaf children with deafness of unknown etiology.

Connexin 26 (GJB2) gene-related deafness and speech intelligibility after cochlear implantation.

HYPOTHESIS: Speech intelligibility in children after cochlear implantation may depend on their deafness cause, including connexin 26 (GJB2) gene-related deafness. BACKGROUND: There is significant variability in the degree of intelligibility, or clarity, of children's speech after cochlear implantation. GJB2 gene-related deafness may be a factor, as preliminary data suggest that pathologic changes do not affect the spiral ganglion cells, which are the neural elements stimulated by the implant, thus favoring better results. METHODS: In an observational retrospective cohort study of pediatric cochlear implantees, 38 patients with nonsyndromic deafness of unknown cause and 1 with keratitisichthyosis-deafness syndrome underwent GJB2 mutation analysis using polymerase chain reaction amplification and direct sequencing. The primary outcome measure assessed was Speech Intelligibility Rating score from postoperative Year 1 (n = 39) to Year 5 (n = 17). Educational setting was considered as a secondary outcome measure. Statistical analysis was double-blinded, with patients and assessors of outcome unaware of GJB2 status. RESULTS: Fourteen patients had GJB2-related deafness and 25 had GJB2-unrelated deafness. Comparisons at Year 3 (n = 31) revealed intelligible speech achieved by 9 of 11 with GJB2-related deafness, compared with only 6 of 20 with GJB2-unrelated deafness (p = 0.017). Ordinal logistic regression analysis on Speech Intelligibility Rating scores found statistically significantly better scores in children with GJB2-related deafness (p < 0.05) both before and after adjustment for confounding variables. A larger proportion with GJB2-related deafness also attended mainstream school (p = 0.01). CONCLUSION: In pediatric cochlear implantees, GJB2-related deafness is a predictor of good speech intelligibility.