Speech understanding in noise for cochlear implant recipients using a spatial noise reduction setting in an off the ear sound processor with directional microphones.

PURPOSE: Cochlear implant (CI) recipients struggle to hear in competing background noise. ForwardFocus is a spatial noise reduction setting from Cochlear Ltd. (Sydney) that can simultaneously attenuate noise from multiple sources behind the listener. This study assessed hearing performance with ForwardFocus in an off-the-ear (OTE) sound processor. METHOD: Twenty-two experienced adult CI recipients participated. Speech reception data was collected in fixed noise acutely in the clinic. After three to five weeks take home experience, subjective impressions were recorded, and evaluations were conducted for speech reception in quiet and roving noise. RESULTS: Group mean speech reception thresholds (SRT) were below 0 dB in two spatially-separated noise test conditions when using ForwardFocus in the OTE sound processor. SRT were -8.5 dB (SD 2.9) in 4-talker babble roving in a rear hemi-field (S0Nrearhemi) and -3.9 dB (SD 3.3) in 12-talker babble presented laterally and behind (S0N3). Results in S0N3 were significantly better with ForwardFocus On (p = 0.0018). Subjective ratings with the OTE were comparable to, or better than, with their walk-in BTE or OTE sound processor. CONCLUSIONS: ForwardFocus provides significant benefits for speech recognition in competing background noise in an OTE sound processor. These results support clinicians in counselling CI recipients on potential sound processor options to consider.

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.

Factors contributing to clinically important health utility gains in cochlear implant recipients.

PURPOSE: Cochlear implantation can restore access to sound and speech understanding in subjects with substantial hearing loss. The Health Utilities Index Mark III (HUI3) measures the impact of an intervention on the patient's quality of life and is sensitive to changes in hearing. In the current study we used factor analysis to predict a clinically important gain in HUI3 scores in adult cochlear implant recipients. METHODS: Data were collected in an observational study for 137 adult recipients from a single center who had at least 1-year HUI3 follow-up. Demographic and other baseline parameters were retrospectively analyzed for their association with a clinically important HUI3 scale gain, defined as at least 0.1 points. Data were also collected for the speech spatial qualities (SSQ) scale. RESULTS: Baseline telephone use and HUI3 hearing, speech and emotion attribute levels were significantly associated with clinically important gains in HUI3 scores. However, SSQ scores increased significantly with or without clinically important HUI3 gains. CONCLUSION: Those subjects who were unhappy or experienced difficulties communicating with strangers or in a group were twice as likely to obtain a clinically important gain in health utility compared to those who were happy or had less difficulty communicating. Subjects who were unable to use the telephone prior to cochlear implantation were one and a half times more likely to obtain a clinically important gain. The SSQ scale was more sensitive to hearing improvements due to cochlear implantation. An inability to use the telephone is an easy to assess biomarker for candidacy for cochlear implantation.

Outcomes for a clinically representative cohort of hearing-impaired adults using the Nucleus® CI532 cochlear implant.

PURPOSE: Hearing performance data was collected from a large heterogeneous group of subjects implanted with the Cochlear™ Nucleus® CI532 with Slim Modiolar Electrode, for the purposes of postmarket clinical follow-up. Data was analysed for factors which may predict postoperative speech recognition scores. METHODS: Data was collected retrospectively from five German clinics for 159 subjects from March 2017 to August 2018. Hearing thresholds and recognition scores for monosyllabic words in quiet and sentences in noise were measured preoperatively and at 3 and 6 months postoperatively. RESULTS: There was a mean gain of 44% points (95% CI 39-49%) at 6 months in monosyllable scores in quiet for implanted ears. Preoperative hearing thresholds in implant ears increased systematically with decreasing age; however, younger subjects had better baseline monosyllable scores with hearing aids compared with older subjects. Baseline performance alone explained 14% of the variation in postoperative scores. Residual hearing was preserved on average to within 22 dB at 250 Hz and 30 dB at 500 Hz of preoperative levels. CONCLUSIONS: In a large and varied cohort of routinely treated hearing-impaired adults, speech recognition with the CI532 for German monosyllabic words in quiet at 6 months was equivalent to performance reported at one year or more in other published studies. Although younger subjects had poorer preoperative pure-tone thresholds, they had better preoperative word recognition scores compared with older subjects, and also had higher post implant scores. Further research is required to identify if this phenomenon is just applicable to German health system assessment and referral practices.

Auditory localization abilities in bilateral cochlear implant recipients.

OBJECTIVE: To quantify binaural advantage for auditory localization in the horizontal plane by bilateral cochlear implant (CI) recipients. Also, to determine whether the use of dual microphones with one implant improves localization. METHODS: Twenty subjects from the UK multicenter trial of bilateral cochlear implantation with Nucleus 24 K/M device were recruited. Sound localization was assessed in an anechoic room with an 11-loudspeaker array under four test conditions: right CI, left CI, binaural CI, and dual microphone. Two runs were undertaken for each of five stimuli (speech, tones, noise, transients, and reverberant speech). Order of conditions was counterbalanced across subjects. RESULTS: Mean localization error with bilateral implants was 24 degrees compared with 67 degrees for monaural implant and dual microphone conditions (chance performance is 65 degrees). Normal controls average 2 to 3 degrees in similar conditions. Binaural performance was significantly better than monaural performance for all subjects, for all stimulus types, and for different sound sources. Only small differences in performance with different stimuli were observed. CONCLUSIONS: Bilateral cochlear implantation with the Nucleus 24 device provides marked improvement in horizontal plane localization abilities compared with unilateral CI use for a range of stimuli having different spectral and temporal characteristics. Benefit was obtained by all subjects, for all stimulus types, and for all sound directions. However, binaural performance was still worse than that obtained by normal hearing listeners and hearing aid users with the same methodology. Monaural localization performance was at chance. There is no benefit for localization with dual microphones.

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.