Repair and re-use of hearing instruments.

Norwegian hearing-impaired persons, since 1 May 1986, have been entitled to free hearing instruments (HI), and also to free repair of defective HIs. In order to reduce the community's expense, national regulation recommends that HIs not in use should be returned to a hearing centre for re-use. To achieve a further reduction of expense, the National Health Insurance (NHI) decided that from 1 January 1989, only persons under 18 years of age could have their HIs repaired free of charge. The NHI supposed that some users of HIs would be unwilling to pay for repair of defective instruments, and realized that this would lead to an increased number of defective HIs remaining among the users. A pilot study performed in 1990 supported this assumption. A further consequence of this change of regulation was that clients, entitled to free HIs, could not be given used instruments with or without reduced guarantee--when they had to pay for repair of the instruments themselves. Therefore, the NHI saved expense through user-paid repair of HIs, yet on the other hand had increased costs by buying new HIs instead of giving some of the clients used instruments. The aim of this investigation was to evaluate whether the NHI could pay for the repair of HIs and have these costs covered by savings from the re-use of HIs. During 1992, 1993 and 1994, the cost for repair of the 5150 HIs was 176,560 pounds. During the same period, 2105 HIs were re-used, representing a saving of 445,712 pounds. This repair/re-use system unburdens the users of HIs of expense, and in turn saves money for the community. For approximately 10% of all HIs sent for repair, the main problem was not that the instruments were defective.

Factors to consider when in-the-canal hearing instruments are used in aural rehabilitation.

The purpose of this investigation was to determine what subjective factors may influence the success of fitting in-the-canal hearing instruments (ITCs). Four different types of ITC were fitted to four matched groups of 20 experienced ITC users. In addition to the subjective experiences of the users, the results were checked using insertion gain (IG) measurements. The results indicate that too sharp sound quality from paper rustle, from running water and from use of kitchen utensils is a common problem that it is important to be aware of. The possibility of maximal venting is of special importance in order to avoid autophony. Feedback may be a problem, especially when maximal venting is necessary. However, for several models of ITC, feedback is, in reality, a minor problem. High cost of batteries may be a problem for persons with ITC using 10/230 batteries. IG measurements indicated that a gain of approximately 0.3 in relation to the hearing losses was preferred. It may be advantageous to choose a model of ITC that has extensive flexibility.

Assistive devices for hard-of-hearing persons--distribution system and costs.

A system to provide hearing-impaired persons with adequate assistive devices is described. Investigation of 100 persons' recommended devices in 1985 shows that the system functions reasonably well. To secure provision of adequate devices, a system must be established to take care of all practical tasks. The mean expense to supply a hearing-impaired person with the assistive devices needed was found to be 764 pounds. Supplying elderly hearing-impaired persons with assistive devices may enable them to stay at home longer. The cost of the required assistive devices for a hearing-impaired person is on average approximately the same as for 8 days' stay in a nursing home.

Hearing instruments for the elderly hearing impaired. A comparison of in-the-canal and behind-the-ear hearing instruments in first-time users.

The purpose of this investigation was to compare negative and positive experiences between two matched groups of elderly first-time users of hearing instruments (HI). One group had been supplied with behind-the-ear hearing instruments (BTE), the other with in-the-canal hearing instruments (ITC). There were 20 persons in each group. All were visited in their homes. Those who needed extra help were offered follow-up at the Hearing Centre. ITC were found to be superior to BTE as regards time-of-use, operational difficulties and undesirable sound experiences. ITC were also used in more difficult listening situations. Successful instruction and follow-up was more easily achieved with ITC users than with BTE users. ITC are recommended as the preferred instrument for elderly first-time HI users, at least for hearing losses not exceeding 60 dB PTA, provided the subject's dexterity and anatomical conditions permit fitting of ITC.

In-the-canal hearing instruments. Benefits and problems for inexperienced users given minimal instruction.

The number of in-the-canal hearing instruments (ITC) distributed annually in our region is increasing. The purpose of this investigation, which included 300 persons, was to evaluate the problems and benefits reported by ITC users who had received a minimum of counselling. Another aim was to decide which factors to concentrate on when teaching local health personnel how to assist hard-of-hearing equipped with ITC. The results showed that 38% had operational difficulties, 63% had experienced untoward sound reception. However, almost 90% reported positive experiences and the overall result for more than 80% was good. Operational difficulties resulted mainly from insufficient instruction. A moderate degree of instruction at the check-up was both essential and beneficial. Untoward sound experiences were caused mainly by inadequate venting and/or inaccurately adjusted instruments, faults that could be easily dealt with. It is therefore essential to teach local health service personnel that clients initially reporting problems in using their ITC can in most cases have their problems solved, mainly by simple instruction and/or an adjustment of the ITC. Only when these measures have failed should other types of hearing instruments (HI) be tried. Local health service personnel should therefore be instructed not to accept initial rejection of ITC merely because of the small size of the instrument until further instruction has been given, and not proved successful.

Unilateral sensorineural hearing loss in children less than 15 years of age.

1-10 years after the first examination, 56 children below 15 years of age with unilateral sensorineural hearing loss were re-examined with a test-battery consisting of puretone and speech audiometry, stapedius reflex tests, caloric tests, brainstem response audiometry and otoneurological tests. In no case was an acoustic tumour suspected on the basis of the test results. A small progression of the hearing loss occurred in only one ear. In no case did the healthy ears develop hearing loss during the observation period. Diagnostic procedures can in most of such cases be limited to pure-tone audiometry. Follow-up is indicated because some patients require advice considering education and evaluation regarding fitting of a hearing aid.

Ventilating tubes in the middle ear. Long-term observations.

This follow-up study is of the same patients we studied in 1976. Then we thought the results were unsatisfactory in 20.9% of the ears treated with ventilating tubes. The hearing losses varied from 25 to 60 dB and chronic otitis media developed in 7.7% of the cases. We think the results of treatment with ventilating tubes in chronic serous otitis media are not good enough. This study shows that there has been an increase in the number of patients with permanent hearing loss and chronic otitis media than in the first study.

Evaluation of hearing aid fitting based on the patients' experiences from everyday listening conditions.

We found that a relationship existed between degree of sensorineural hearing loss and discrimination score obtained in free field with convenient hearing aids against background noise. However, the standard deviation was so great that we could not elaborate a diagram from which, with any reasonable degree of accuracy the expected discrimination score with suitable hearing aids could be predicted for each individual patient. Then 20 patients with sensorineural hearing losses tried different hearing aids under everyday listening conditions, and simplified speech audiometry against background noise was performed. We found that none of the patients achieved better discrimination scores with aids they rejected under everyday listening conditions than with aids they preferred. This indicates that we need to pay attention to the patient's experience with hearing aids under everyday listening conditions in each individual case, when a hearing aid is to be selected.

The reliability of level-diagnostic examinations in acute, peripheral facial palsy.

In acute non-traumatic peripheral facial palsy where the cause is not known, it does not seem to be justified to draw conclusions as to how far to the centre in the course of the nerve the lesion may be located, based on an examination of tear secretion, stapedial reflex, and taste. This is demonstrated in two cases.

Ventilating tubes in the middle ear.

One hundred children from 1 to 14 years of age had serous otitis media, the manifestations of which were bilateral in all but four patients. Thus, 196 ears were treated with aeration of the middle ear by means of a short transmyringeal tube. The mean duration of the treatment was 3.4 years, and the mean observation time was 7.3 years. Of the ears treated, 79.1% regained normal hearing, though scarring of the tympanic membrane and smaller adhesions were observed. The result was not satisfactory in 20.9% of the ears treated, the hearing losses varying from 25 to 60 dB. In 7.7% (15 ears) chronic otitis media developed; in 5.6% (11 of the 15 ears) cholesteatoma was confirmed surgically. Adhesive processes were present in 11.2%.

Auditory localization and its clinical applications.

Factors of significance in the localization of sound are considered. The ability of hearing-impaired subjects to localize noise in the horizontal plane was examined with and without hearing aids, and also compared with the results for normally hearing subjects. The directional hearing was not found to be improved by the hearing aids used. The ability to localize sound has been used by several investigators as a diagnostic tool: poor directional hearing may be expected in patients with lesions of the cochlear nerve or the pontine region. However, other factors are also of significance and may impair the localization of sound. These problems are discussed.