OBJECTIVES: New signal processing technologies have recently become available for Baha(R) sound processors. These technologies have led to an increase in power and to the implementation of directional microphones. For any new technology, it is important to evaluate the degree of benefit under different listening situations. METHODS: Twenty wearers of the Baha osseointegrated hearing system participated in the investigation. The control sound processor was the Baha Intenso and the test sound processor was the Cochlear(TM) Baha(R) BP110power. Performance was evaluated in terms of free-field audibility with narrow band noise stimuli. Speech recognition of monosyllabic phonetically balanced (PB) words in quiet was performed at three intensity settings (50, 65, and 80 dB sound pressure level [SPL]) with materials presented at 0 degrees azimuth. Speech recognition of sentences in noise using the Hearing in Noise Test (HINT) in an adaptive framework was performed with speech from 0 degrees and noise held constant at 65 dB SPL from 180 degrees. Testing was performed in both the omni and directional microphone settings. Loudness growth was assessed in randomly presented 10 dB steps between 30 and 90 dB SPL to narrow band noise stimuli at 500 Hz and 3,000 Hz. RESULTS: The test sound processor had significantly improved high frequency audibility (3,000-8,000 Hz). Speech recognition of PB words in quiet at three different intensity levels (50, 65, and 80 dB SPL) indicated a significant difference in terms of level (P<0.0001) but not for sound processor type (P>0.05). Speech recognition of sentences in noise demonstrated a 2.5 dB signal-to-noise ratio (SNR) improvement in performance for the test sound processor. The directional microphone provided an additional 2.3 dB SNR improvement in speech recognition (P<0.0001). Loudness growth functions demonstrated similar performance, indicating that both sound processors had sufficient headroom and amplification for the required hearing loss. CONCLUSION: The test sound processor demonstrated significant improvements in the most challenging listening situation (speech recognition in noise). The implementation of a directional microphone demonstrated a further potential improvement in hearing performance. Both the control and test sound processors demonstrated good performance in terms of audibility, word recognition in quiet and loudness growth.
Bone Conduction ; Hearing ; Hearing Aids ; Hearing Loss, Mixed Conductive-Sensorineural ; Humans ; Noise ; Osseointegration ; Sensory Aids ; Signal-To-Noise Ratio

OBJECTIVES: Variability in Baha(R) sound processor fittings may arise from the nature of the implant-to-bone transmission as well as transcranial attenuation for patients with single-sided sensorineural deafness (SSD). One method of improving the predictability of Baha fittings is to measure the individual patient's actual bone conduction thresholds, thereby removing the influences of skin thickness and/or the implant location site. METHODS: Twenty adult wearers of the Baha bone conduction implant system participated in the study. Direct bone conduction thresholds were obtained through the BC Direct function of the Baha Fitting Software combined with the Cochlear Baha BP100 sound processor. For comparison, the masked and unmasked bone conduction responses of the patients were collected through standard audiometric testing techniques. Test-retest reliability measurement was performed for all participants. Data for each frequency and frequency range were analyzed separately. RESULTS: The results confirm the improved transmission of sound through the implant rather than transcutaneously through the skin. On average, the BC Direct thresholds were closer to the patient's unmasked thresholds than the masked values. In subjects with SSD, BC Direct results were poorer than contra-lateral bone conduction thresholds, most likely due to transcranial attenuation. The test-retest reliability for the BC Direct measurements was within +/-5 dB. The comparison of preferred amplification, based on direct bone conduction or bone conduction audiometry, found higher agreement for fittings based on direct bone conduction measurements. CONCLUSION: While the transfer function between the implant and the skin can be predicted on average, there are a number of patients for whom measurement is essential to determine the required amplification. These were patients with: 1) SSD, 2) asymmetrical hearing loss, 3) unusual implant location or skull formation, and 4) users of Testband or Softband. The result for the clinician is that a fitting can take place with less fine-tuning and a greater understanding of the variability of bone conducted sound transmission.
Adult ; Audiometry ; Bone Conduction ; Deafness ; Hearing Aids ; Hearing Loss ; Humans ; Hypogonadism ; Masks ; Mitochondrial Diseases ; Ophthalmoplegia ; Osseointegration ; Sensory Aids ; Silver Sulfadiazine ; Skin ; Skull

Between one and three of every 1,000 neonates have sensorineural hearing loss (SNHL). It is of utmost importance to minimize the duration of auditory deprivation between the onset of bilateral deafness and intervention using hearing devices such as hearing aids and cochlear implants for achieving the best speech percpetion ability. To fit amplification accurately for children with SNHL, hearing thresholds for frequencies in the range of human communication should be evaluated. However, infants and young children are difficult to test using conventional behavioral tests, and hearing thresholds of them can be predicted using auditory brainstem response (ABR) and auditory steady-state response (ASSR). ABR is best evoked by applying a click stimulus, which allows an estimate over a broad range of high frequencies. ABR elicited by tone burst stimulus provides frequency-specific audiometric information. However, it can be difficult to record and observe at near-threshold levels, especially at lower frequencies. ABR thresholds for click and tone burst stimuli are highly correlated with behavioral thresholds, and often give an idea of the shape of an audiogram. ASSR is an auditory evoked potential, elicited with modulated tones. It provides frequency-specific hearing thresholds across the audiometric frequencies, which are well correlated with behavioral thresholds. However, the accuracy of threshold prediction decreases directly with the decrease of degree of hearing loss, and hearing thresholds cannot be predicted for auditory neuropathy. ASSR is most useful for estimating auditory thresholds for patients with no evidence of auditory neuropathy by the click ABR and OAEs, and who have an ABR only at high intensities or no ABR at a maximum stimulus level. Even if hearing thresholds are predicted through ABR and ASSR, behavioral testing including behavioral observation audiometry, visual reinforcement audiometry, or play audiometry should be employed repeatedly to verify the predicted thresholds, becasue the thresholds of ABR and ASSR are not true measure of hearing acuity but just responses generated at the brainstem.
Audiometry ; Auditory Threshold ; Brain Stem ; Child ; Cochlear Implants ; Deafness ; Evoked Potentials, Auditory ; Evoked Potentials, Auditory, Brain Stem ; Hearing ; Hearing Aids ; Hearing Loss ; Hearing Loss, Central ; Hearing Loss, Sensorineural ; Humans ; Infant ; Infant, Newborn ; Reinforcement (Psychology)

Visually impaired people face many inconveniences because of the loss of vision. Therefore, scientists are trying to design various guidance systems for improving the lives of the blind. Based on sensory substitution, auditory guidance has become an interesting topic in the field of biomedical engineering. In this paper, we made a state-of-technique review of the auditory guidance system. Although there have been many technical challenges, the auditory guidance system would be a useful alternative for the visually impaired people.
Acoustics ; Auditory Perception ; Biomedical Engineering ; Equipment Design ; Humans ; Sensory Aids ; Software ; Sound Localization ; Visual Perception ; Visually Impaired Persons ; rehabilitation

Auditory neuropathy is a hearing disorder characterized by an absent or severely abnormal auditory brainstem response, with preservation of the cochlear microphonics and otoacoustic emissions. This suggests that outer hair cell (OHC) function is normal but that auditory function proximal to the OHCs is impaired. These patients demonstrate mild to severe hearing loss for pure tones and impaired word discrimination out of proportion to pure tone loss. Hearing aid alone is of little or no benefit in patients with auditory neuropathy. Visual support via cued speech or signed language can be a fail-safe method for insuring language development. Recently, there are some reports that cochlear implantation is highly successful in patients with auditory neuropathy. We report three cases (two children and one woman) with auditory neuropathy. Each patient was tested with cochlear microphonics, otoacoustic emissions, auditory brainstem response and middle latency response, etc. All three patients had normal cochlear microphonics or otoacoustic emissions with absent auditory brainstem response. Two of them had evidence of a peripheral neuropathy. We should be aware of auditory neuropathy and implications for its management, which differs from treatment of sensorineural hearing loss. Auditory neuropathy also raises a concern about the risk of false-negative findings when newborn hearing screening is restricted to otoacoustic emissions.
Child ; Cochlear Implantation ; Cochlear Implants ; Discrimination (Psychology) ; Evoked Potentials, Auditory, Brain Stem ; Hair ; Hearing ; Hearing Aids ; Hearing Disorders ; Hearing Loss ; Hearing Loss, Sensorineural ; Humans ; Infant, Newborn ; Language Development ; Mass Screening ; Peripheral Nervous System Diseases

Hearing loss in newborns is the most frequently occurring birth defect. If hearing impaired children are not identified and managed early, it is difficult for many of them to acquire the fundamental language, social and cognitive skills that provide the foundation for later schooling and success in society. All newborns, both high and low risk, should be screened for hearing loss in the birth hospital prior discharge (Universal Newborn Heaing Screening, UNHS). Objective physiologic measures must be used to detect newborns and very young infants with hearing loss. Recent technological developments have produced screening methods and both evoked otoacoustic emission (EOAE) and auditory brainstem response (ABR) have been successfully implemented for UNHS. Audiologic evaluation should be carried out before 3 months of age and infants with confirmed hearing loss should receive intervention before 6 months of age. All infants who pass newborn hearing screening but who have risk indicators for other auditory disorders and/or speech and language delay receive ongoing audiologic surveillance and monitoring for communication development. Infants with sensorineural hearing loss are managed with hearing aids and receive auditory and speech-language rehabilitation therapies. Cochlear implants can be an outstanding option for certain children aged 12 months and older with severe to profound hearing loss who show limited benefit from conventional amplifications.
Child ; Cochlear Implants ; Congenital Abnormalities ; Evoked Potentials, Auditory, Brain Stem ; Hearing Aids ; Hearing Loss ; Hearing Loss, Sensorineural ; Hearing* ; Humans ; Infant ; Infant, Newborn* ; Language Development Disorders ; Mass Screening* ; Parturition ; Rehabilitation

BACKGROUND AND OBJECTIVES: Given that only a few studies have focused on the bimodal benefits on objective and subjective outcomes and emphasized the importance of individual data, the present study aimed to measure the bimodal benefits on the objective and subjective outcomes for adults with cochlear implant. SUBJECTS AND METHODS: Fourteen listeners with bimodal devices were tested on the localization and recognition abilities using environmental sounds, 1-talker, and 2-talker speech materials. The localization ability was measured through an 8-loudspeaker array. For the recognition measures, listeners were asked to repeat the sentences or say the environmental sounds the listeners heard. As a subjective questionnaire, three domains of Korean-version of Speech, Spatial, Qualities of Hearing scale (K-SSQ) were used to explore any relationships between objective and subjective outcomes. RESULTS: Based on the group-mean data, the bimodal hearing enhanced both localization and recognition regardless of test material. However, the inter- and intra-subject variability appeared to be large across test materials for both localization and recognition abilities. Correlation analyses revealed that the relationships were not always consistent between the objective outcomes and the subjective self-reports with bimodal devices. CONCLUSIONS: Overall, this study supports significant bimodal advantages on localization and recognition measures, yet the large individual variability in bimodal benefits should be considered carefully for the clinical assessment as well as counseling. The discrepant relations between objective and subjective results suggest that the bimodal benefits in traditional localization or recognition measures might not necessarily correspond to the self-reported subjective advantages in everyday listening environments.
Adult ; Cochlear Implants ; Counseling ; Hearing ; Hearing Aids ; Humans

Cochlear Implants ; Congresses as Topic ; Hearing ; Hearing Aids ; Humans

OBJECTIVES: Speech intelligibility is severely affected in children with congenital profound hearing loss. Hypernasality is a problem commonly encountered in their speech. Auditory information received from cochlear implants is expected to be far superior to that from hearing aids. Our study aimed at comparing the percentages of nasality in the speech of the cochlear implantees with hearing aid users and also with children with normal hearing. METHODS: Three groups of subjects took part in the study. Groups I and II comprised 12 children each, in the age range of 4-10 years, with prelingual bilateral profound hearing loss, using multichannel cochlear implants and digital hearing aids respectively. Both groups had received at least one year of speech therapy intervention since cochlear implant surgery and hearing aid fitting respectively. The third group consisted of age-matched and sex-matched children with normal hearing. The subjects were asked to say a sentence which consisted of only oral sounds and no nasal sounds ("Buy baby a bib"). The nasalance score as a percentage was calculated. RESULTS: Statistical analysis revealed that the children using hearing aids showed a high percentage of nasalance in their speech. The cochlear implantees showed a lower percentage of nasalance compared to children using hearing aids, but did not match with their normal hearing peers. CONCLUSION: The quality of speech of the cochlear implantees was superior to that of the hearing aid users, but did not match with the normal controls. The study suggests that acoustic variables still exist after cochlear implantation in children, with hearing impairments at deviant levels, which needs attention. Further research needs to be carried out to explore the effect of the age at implantation as a variable in reducing nasality in the speech and attaining normative values in cochlear implantees, and also between unilateral versus bilateral implantees.
Acoustics ; Child ; Cochlear Implantation ; Cochlear Implants ; Hearing ; Hearing Aids ; Hearing Loss ; Humans ; Speech Intelligibility ; Speech Therapy

BACKGROUND AND OBJECTIVES: In this study, we compared the postoperative open-set speech perception abilities of children using implants against their preoperative residual hearing abilities and also compared the performance of cochlear implant users with that of age-matched hearing aid users. SUBJECTS AND METHOD: Ninety-nine prelingually deaf children who have used implants over 1 year were grouped based on the unaided pure tone audiometry (PTA) thresholds into 3 groups: CI91-100(91-100 dB HL), CI101-110 (101-110 dB HL) and CI>111 (over 111 dB HL). Ninety-eight prelingually deaf children with hearing aids were divided into 4 groups also based on the unaided PTA thresholds: HA71-80 (71-80 dB HL), HA81-90 (81-90 dB HL), HA91-100 (91-100 dB HL) and HA101-110 (101-110 dB HL). Children with implants were tested by open-set speech perception tests (Monosyllabic Word, Common Phrases) before implantation and at 6, 12, 18, 24, 36, 48, and 60 months after implantation. Children with hearing aids were tested once or more times using open-set speech perception tests. The open-set speech perception abilities of children with implants and hearing aids were compared before implantation and at 30 months after implantation. RESULTS: The speech perception scores of CI91-100 were higher than those of CI101-110 and CI>111 for the first 2 years of implant use (p<0.05), and were higher than those of CI>111 at 3 years after implantation (p<0.01). Speech-perception scores of CI91-100 were lower than those of HA71-80, HA81-90 and HA91-100 before implantation, but were superior to those of HA91-100 and HA101-110 at 30 months after implantation (p<0.05). Performance of CI101-110 and CI>111 were poorer than that of HA71-80, HA81-90 and HA91-100 before implantation, but exceeded that of HA101-110 at 30 months after implantation (p<0.05). CONCLUSION: Open-set speech perception performance of children with cochlear implants was better than that of hearing aid users of the corresponding hearing level and was similar to at least that of hearing aid users with PTAs of 81-90 dB HL. Therefore, some of children with severe hearing loss may become good candidates for cochlear implantation.
Audiometry ; Child* ; Cochlear Implantation ; Cochlear Implants* ; Hearing Aids* ; Hearing Loss ; Hearing* ; Humans ; Speech Perception*