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H G Dieroff

Publications and source records attributed to H G Dieroff.

At least 19 recordsLinked to original sources
PubMed1992

[The definition of "selectivity" in reduced speech discrimination as a sequela of peripheral perceptual damage].

The term "selectivity" means the ability to correctly select speech in the presence of other kinds of noise. In the literature the term "selectivity" is used very differently with regard to the different levels of the hearing system. In actual practice a separation of this term is important for possible audiometric topodiagnosis study. The problems of selectivity in hearing are discussed and different terms are proposed regarding the different planes of hearing system: 1. for the interaural-external ear transfer function, the terms "stereophonic outer ear effect" or "stereophonic outer ear efficiency" are used; 2. for the power of the inner ear, the term "ability of analysis"; 3. for the central auditory pathways, the term "chiasmatic selectivity" or "meshing selectivity"; 4. for the cortical centre, "active selectivity." The audiometric test batteries used clinically for topodiagnosis are discussed and two examples shown to illustrate the usefulness of the distorted Freiburg Word Test for detecting "analytical ability" in cases of inner ear damage.

Attention↗
PubMed1991

[Experiences with high-frequency hearing tests in the selection of personnel for noise occupations].

A total of 181 persons aged between 16 and 18 were checked fully audiometrically (conventional and high-frequency audiogram). Dates of history about hereditary hearing damage, own ear diseases, noise exposure during frequent visits to discothecs or usage of Walkman etc. were ascertained by questionnaires. The evaluation of the results was carried out with the help of discrimination analysis allowing a multi-dimensional classification. As a result there could be made a sure discrimination analytic separation in persons with ear diseases during their childhood, when the high frequencies from 10 to 15 kHz were taken in. Thus the damage of the inner ear was to be found mainly on the base of the cochlea. Also in cases of hereditary influence there was to be seen a clear deminution in the high frequency area. The group of persons, who regularly went to discos (more than three times a month) as well as the group often using Walkman revealed a sure separation, when the high frequencies above 8 kHz were considered in the calculation. Altogether there could be seen an early damage more clearly in the high frequency area after ear diseases in childhood as well as a result of sound overloading than in conventional hearing area.

Adolescent↗
PubMed1990

[The accuracy of subjective determination of auditory threshold in the range of 0.5 to 18.0 kHz using different sound transducer systems].

This paper reports on the degree of accuracy of determinations of hearing threshold in the 0.5 to 18 kHz range. As far as possible, these hearing thresholds were compared with those of ISO 389. Furthermore, the study compared determinations of hearing thresholds measured on different days. Reproducibility was very good, particularly of the high-frequency thresholds. The two types of sound transducers used here (a quasi-free field system developed by the authors and a pair of professional headphones) showed an identical transmission of frequencies and good reproducibility of the results of measurements.

Adult↗
PubMed1989

High-frequency audiometry in the evaluation of critical noise intensity.

We investigated a total of 537 subjects (68 men, 469 women) working in the textile industry to ascertain their hearing level in the conventional hearing range as well as in the high-frequency (HF) range. The persons we tested work at three different noise-levels [80-84, 85-89, 90-94 dB (A), measured as leq). The differences in the hearing thresholds between this three groups mentioned were checked by means of discriminant analysis. The first hearing level changes at a noise-level below 90 dB (A) leq develop mainly in the HF range. In the conventional hearing range, however, the hearing levels remain unchanged even over long exposure times. Noise-induced hearing loss in the conventional range occurs only in the sound level group of 90 to 94 dB (A) leq without attaining any social importance. The tests show that, if the noise-level 90 dB (A) leq is not exceeded, no noise-induced hearing impairments involving social hearing loss are to be observed. Thus we assume that an auditory risk criterion of 85 dB (A) leq is sufficient to prevent hearing loss of any social importance.

Adult↗
PubMed1989

[Experiences with the distorted Freiburg Speech Test--diagnosis and rehabilitation of hearing disorders].

In accordance with the description of an extended technique of distorted speech at different values - 15 dB, - 10 dB, - 5 dB and 0 dB with the plotted frequency characteristic, we used the procedure with different kinds of sensorineural hearing loss. The method analyse the peripheral hearing system very simply. In cases of acoustic tumours the quotient is very large and it is better to reduce the degree of distortion (-10, -5 and 0 dB). Generally, it is possible to detect the phase of degeneration of the inner hair-cells and afferent nerve fibres in all cases of sensorineural hearing loss. The test is also of very good help in fitting hearing aids because method picks out the hard hearing persons with very disturbed discrimination of speech.

Adult↗
PubMed1989

[Manifestations of inactivity in unilateral hearing aid management of patients with a high degree of hearing loss].

Concluding from audiometrical practice using hearing aids unilaterally we could find an inactivity of the unused contralateral ear. We have investigated if it is possible to measure this inactivity by common psychoacoustic methods. We tested 92 persons with advanced combined hearing loss. We had to state that the inactivity is not measurable by mean tone hearing loss according to HAIC (0.5, 1 and 2 kHz), the percentage hearing loss according to Fowler-Sabine, the percentage of hearing loss calculated by speech-audiogram according to Boenninghaus and Röser 1973 and the value of hearing loss for speech (a1). It is only a big discrimination loss that points to the presence of inactivity. The discrimination loss was compared in two groups concerning "used" and "unused" ears. We could clearly measure the biggest discrimination loss in the group of unused ears. The clinical consequences were discussed.

Attention↗
PubMed1989

[High-frequency audiometry for the early diagnosis of occupational acoustic trauma].

We investigated a total of 537 patients (68 men, 469 women) working in the textile industry to ascertain their hearing level in the conventional hearing range as well as in the HF range. The persons tested work at 3 different noise levels (80-84, 85-89 and 90-94 dB [A] Leq). The differences in the hearing thresholds of the three sound level groups mentioned above were checked by means of discrimination analysis. The first hearing level changes noise levels below 90 dB develop mainly in the HF range; in the conventional hearing range, however, the hearing levels remain unchanged even during long exposure times. Hearing level impairment in the conventional range occurs only in the sound level group of 90-94 dB (A) Leq without attaining any social importance. The tests clearly show that if the noise level damage risk criterion of 85 dB (A) Leq at which hearing is impaired, is not exceeded any hearing lesions involving social hearing loss are definitely avoided.

Adult↗
PubMed1987

[Assessment of social hearing with a questionnaire in relation to average hearing loss].

In 86 patients with sensorineural hearing loss we checked if the measuring results obtained by conventional audiometric procedures correlate with the subjective impression of hard hearing ascertained via a special questionnaire. For this purpose we compared the average hearing loss (500, 1000, 2000 Hz) of the puretone audiogram with the results obtained via the questionnaire developed by v. Wedel and Tegtmeier for assessing the social hearing handicap (SHH). We can see that there is good correlation between the SHH index values and the average hearing loss with frequencies of 0.5, 1.2 kHz in pancochlear perception hearing loss, whereas in patients with basocochlear perception hearing loss the SHHI cannot be calculated with the help of the puretone audiogram, nor will a widening of the frequency range up to 6 kHz lead to a better correlation between the average hearing loss and SHHI.

Aged↗
PubMed1986

Influence of different kinds of noise on the ear and some physiological and psychological parameters.

The reactions of the human organism to noise are complicated and difficult to separate from other stressors, with the exception of hearing damage. After thorough experimental planning and a rigorous selection of sample persons, the reaction to noise of varying structures was studied by reactions of heart rate, blood pressure, reaction time, the temporary threshold shift (TTS) of hearing and the psychological parameters "Mood" (in German "Befinden"). We found a special kind of TTS dependent on the structure o noise and no effect of physiological parameters. The psychological parameter tended to have a significant influence on individual factors.

Audiometry↗
PubMed1986

High frequency hearing following otitis media with effusion in childhood.

78 children had been treated for secretory otitis media at the age of 4.4, on the average. At the age of 18.6, their hearing was checked by means of conventional and high frequency (HF) audiometry. In the conventional range, the average hearing level was nearly normal and no air-bone gap could be found. In HF-range, the average hearing level decreased clearly but the HF-hearing level was significantly affected only in cases in which an air-bone gap exceeding 40 dB and more had existed during the active secretory otitis.

Child, Preschool↗
PubMed1986

[The problem of critical intensity].

We investigated a total of 537 patients (68 men, 469 women) working in the textile industry to ascertain their hearing level in the conventional hearing range as well as in the HF range. The persons tested work at 3 different noise levels (80-84, 85-89 and 90-94 dB (A) Leq. The differences in the hearing thresholds of the three sound level groups mentioned above were checked by means of discrimination analysis. The first hearing level changes noise levels below 90 dB develop mainly in the HF range; in the conventional hearing range, however, the hearing levels remain unchanged even during long exposure times. Hearing level impairment in the conventional range occurs only in the sound level group of 90-94 dB (A) Leq without attaining any social importance. The tests clearly show that if the noise level damage risk criterion of 85 dB (A) Leq at which hearing is impaired, is not exceeded any hearing lesions involving social hearing loss are definitely avoided.

Adolescent↗
PubMed1985

[Distorted Freiburg Speech Test].

In 107 patients with different types of hearing loss (air conduction, sensorineural and combined) we ascertained the monaural discrimination loss of monosyllables with the help of the normal and distorted Freiburg speech test. It was evident that the quotient obtained from the measured discrimination is a very good and useful measure to characterise the ability to analyse the peripheral hearing system. Compared with normal hearing individuals and patients with air conduction hearing loss or combined loss of hearing, persons with perception hearing loss show a much greater and more divergent quotient. The discrimination of distorted speech depends more on age than that of normal speech; however, it is considerably reduced from the sixth decade of life onwards. The distortion test offers the expertising the possibility of improved assessment of speech discrimination by workers in a noisy environment in case of unfavourable hearing conditions, but it is also of considerable importance in fitting hearing aids and in the diagnosis of acoustic tumours.

Adolescent↗
PubMed1977

[The reliability of audiometry based on conscious orientation of the hearing impaired child (author's transl)].

The authors present the audiometric procedure for hearing impaired children, which has been developed and performed routinely for some years by the Department of Audiology in the ENT-Clinic of the Friedrich-Schiller-University Jena. Problems of children's audiometry are discussed. The procedure developed, is based on the children's conscious orientation to the source of sound which can regularly be registered especially in children of the age from 5 or 6 months to 3 or 4 years. The threshold provoking orientation is 45 to 50 dB (absolute). The results gained by the method described are compaired with those which were obtained 4 to 9 years later in 41 subjects suffering from heredodegenerative hearing loss. A coefficient of correlation r = 0.77 was found, indication a very near correlation of results for both procedures. When compaired to ERA, the test presented is simple to perform and is though to be very valuable for praxis. The orientation audiometry is more exact than the test of subjective audiometry and various procedures based on acoustical reflexes, too.

Age Factors↗
PubMed1976

Possibilities of improving the diagnosis of noise-induced hearing damage by means of directional audiometry, the dichotic speech discrimination test, and the EEG1.

Several audiometric tests were made of 85 noise workers exposed to an intensive impulse noise during pressing and punching. These tests aimed at finding out noise-induced central hearing damages (directional audiometry, dichotic speech discrimination test according to Feldmann and checking of the induction of the impedance jump). In addition, a clinical EEG was taken from each subject. Having obtained the necessary norms with series of tests in subjects with normal hearing abilities for their respective ages, the following results have been obtained: (1) directional hearing has hardly been affected by noise-induced hearing damage. It behaves like age changes in the group compared with it; (2) the dichotic speech discrimination test shows increasingly pathological values with progressive noise-induced hearing damage; this was already obvious in the age group 41-50. The impedance jump is less and less produced with progressive noise-induced hearing damage and finally disappears at a noise intensity of up to 110 dB. Because of these findings a progressive degeneration of the spiral ganglion and hearing nerve in noise-induced hearing damage is discussed as a cause of a deteriorated speech discrimination and the absence of the impedance jump. The EEG findings show changes in the alpha-rhythm in about 50% of the cases at an exposure time of 10 years onwards which may be possibly due to damage to the reticular formation, once increasing noise-induced hearing damage no longer exists.

Adult↗