Original publications on speech audiometry published during the past 10 years were analyzed to survey study trends in speech audiometry. The journal names, study objectives, subjects, study methods, and terms in the report titles were examined. The analysis showed that speech audiometry has been mostly used to evaluate hearing aids and cochlear implants. The second most common purpose was to record the results of speech audiometry in case reports. A few papers used speech audiometry to analyze confused speech perception or as part of a differential diagnosis of hearing impairment. Compared with study trends in speech audiometry for 30 years ago, the present investigation revealed a reduction in the importance of speech audiometry as a tool for the differential diagnosis of hearing impairment. Considering the increasing number of hearing-impaired people in today's aging society, speech audiometry might become a more important method for evaluating speech perception ability.
The purpose of this study was to evaluate the benefit of cochlear implants (CI) and hearing abilities in post-lingual hearing impaired adults with CI. Twelve recipients with CI underwent the speech perception test and the Self-Assessment Scale for the Japanese hearing impaired. The recipients and their family also filled out a questionnaire about their CI and hearing in daily life, and the total hearing image of the recipients was assessed on a visual analog scale (VAS). The results showed that the large majority of the recipients and their families were satisfied with CI, especially during face to face conversation. An improvement in the social skills and the quality of life (QOL) was also recognized. Speech perception abilities correlated with the period of deafness but not the total score of the Self-Assessment Scale. The VAS score of the total hearing image of the CI recipients assessed by the family was significantly higher than that by the recipients in the good hearing group. In conclusion, this study showed that CI contributed to the better hearing and QOL of the recipients. Because of the discrepancy between the evaluations of the recipients and their families, careful support was deemed necessary not only for patients with CIs but also for their families.
We examined the status of twenty-eight infants with hearing loss who had not undergone auditory screening when newborns to identify problems. Of thirteen infants with severe or advanced hearing loss who showed no risk factor, the parents of only three infants noticed their hearing problem and consulted a physician before their child's first birthday. Since it is very difficult to identify hearing loss in infants who do not undergo screening, it is important to recommend to their parents to utilize a checklist for hearing development. During the 1.5- and 3-year-old checkups, some parents who had been worried about a delay in their children's language development were advised to have them undergo an auditory test. Therefore, auditory tests in these checkups are very important. Hearing loss in eight children with risk factors was identified at an early stage since they had undergone auditory tests regularly at the recommendation of a pediatrician. Of these eight infants, three with congenital diaphragmatic hernia were diagnosed as having progressive hearing loss during a regular auditory examination. It is important for infants with risk factors to undergo auditory tests on a regular basis because they are likely to develop delayed or progressive hearing loss.
In order to assess the usefulness of 10 items selected from “The Questionnaire on Hearing 2002” as a tool of subjective validation of hearing aid fitting, it was administered to hearing impaired patients and the results were analyzed. The results of 232 cases with hearing aids suggested that the median of scores is a proper criterion for the validation of hearing aid fitting. Furthermore, the decrease in scores observed in the results of 82 cases suggested that the decrease in one score from before to after the hearing aid fitting can be another criterion. To validate the hearing aid fitting based on those criteria, a trial form for recording the scores of the 10-item questionnaire was developed.
Asymmetric bilateral directional fitting (ABDF) has been reported by Bentler et al8) in 2004, in which the hearing aid in one side was on directional microphone mode while the contralateral side was on omnidirectional mode. The authors reported that there was no significant difference in speech recognition thresholds (SRT) using HINT or word recognition scores between the conditions of asymmetric fitting and symmetric fitting. On the other hand, Hornsby et al.9) reported that there was a significant difference between the two conditions and concluded that symmetric bilateral directional fitting (SBDF) was better. In this study, the SRTs in 28 normal hearing and 13 hearing impaired participants were measured to find the directional benefit of ABDF. As predicted, SRTs in noise and directional benefit were the best in SBDF, ABDF, and bilateral omnidirectional in that order. SBDF had a 1-1.5 dB directional advantage on average compared to ABDF. However, ABDF was still approximately 3dB better than bilateral omnidirectional fitting. There was no significant difference between asymmetric and symmetric directional in terms of directional benefit in the hearing impaired group only. The findings suggested that asymmetric fitting would still be beneficial in the order of 3 dB compared to bilateral omnidirectional, and certainly it can be considered as an option for those who want to receive the advantage of directional microphone mode yet do not want to miss hearing sounds in their environment from all directions.
We followed the developmental progress over the long-term of 4 children wearing cochlear implants (C.I.) and also, for comparison, that of a child wearing a hearing aid, and made the following observations. The articulation development level of children who had started wearing a C.I. before or at the age of 2 years was similar to that of children with normal hearing; children who started wearing a C.I. at the age of 6 years also showed improvement of the articulation ability, although they showed variations in the development rate of the articulation ability. Children who started wearing a C.I. after the age of 7 years showed slow improvement of articulation, although there remained the fear of residual difficulties in articulation. It was found that both a young age at the start of wearing of a C.I. and a long duration of wearing of a C.I. had beneficial effects on the acquisition of the ability to articulate. It was considered that the articulation ability developed based on that of the language ability, and the level of acquisition varied according to the developmental condition of the children at the age of 6 to 7 years, at which acquisition of articulation ability is completed in children with normal hearing.