[Hearing loss caused by leisure noise]

[Pyroban on New Year's Eve 2020 & 2021 - Analysis of firework-related injuries over the last 12 years]

There is an increase of firework-related injuries in Germany at the turn of the year. With regard to hearing, a distinction is made between blast (BT) and explosion trauma (ET). The study examines the prevalence and characteristics of firework-related injuries and the impact of the COVID-19-pandemic pyrotechnic ban on New Year's Eve 2020/21 and 2021/22 compared to the 10-year period prior to the pandemic.A retrospective chart review of all patients who presented themselves with the diagnosis blast trauma (H 83.3) or explosion trauma (T 70.8) at the Charité emergency service in the last 12 years from Dezember 28 to January 5 was performed.276 patients were recorded, 77% of whom were male. 1/3 each were assigned to the age group 10-19 and 20-29 years. 21% of the patients were admitted to the hospital. There was an isolated BT of the ear in 67%, hand injuries in 11%, head injuries in 8% and eye injuries in 4%. 87% had ear involvement with hearing loss; 5% of these with ET.8% of the patients underwent surgical interventions. The treatment of a tympanic membrane perforation was carried out by: 54% splinting, 38% tympanoplasty. Therapy with a glucocorticoid was administered i.v. in 48%. and initiated orally in 20%. Overall, there was a nearly 75% decrease in injuries in 2020 and 2021 compared to the previous 10-year period.The use of fireworks leads to increased utilization of health care resources. The ban on the sale of pyrotechnics as well as the introduction of pyro ban zones in 2020 and 2021 led to a relevant decrease in injuries. 2020 and 2021 were the only years in which there were no injuries in children. The BT of the ear is the most common firework-related injury.

Exposure to leisure noise and intermittent tinnitus among young adults in Bavaria: longitudinal data from a prospective cohort study

OBJECTIVES

To investigate the association between total leisure noise exposure and intermittent tinnitus among young adults.

DESIGN

Data were obtained from the Ohrkan study, an ongoing prospective cohort study conducted in South Germany since 2009. Information about exposure to impulse and leisure noise, tinnitus occurrences, sociodemographic variables, and self-rated hearing ability were analysed at four time points over a period of seven and a half years.

STUDY SAMPLE

Participants of the Ohrkan cohort study, who provided data about the occurrence of tinnitus for all surveys (n = 1028).

RESULTS

Intermittent tinnitus was reported in the majority of the sample (60%). The risk for intermittent tinnitus increased with higher sound pressure levels from exposure to leisure noise (full model (Odds Ratio, 95%CI): 80-<85dB(A): 1.41 [1.13-1.78], 85-<90dB(A): 1.73 [1.38-2.16], >90dB(A): 2.04 [1.59-2.61]). Visiting nightclubs was a major contributor to this relationship. Of the considered covariables, self-rated hearing as "poor", and growing up in a single-parent household were significantly associated with intermittent tinnitus.

CONCLUSION

Intermittent tinnitus is very frequent among young adults and is associated with high levels of leisure noise exposure. To prevent intermittent tinnitus, reduced sound pressure levels and the use of hearing protection are necessary.

Effects of a hearing protection campaign on the discotheque attendance habits of high-school students: Efectos de una campaña de protección auditiva en los hábitos de asistencia a discotecas de estudiantes de educación media

This study investigated whether a hearing education campaign would prompt adolescents to display hearing-protective behaviour when attending a discotheque. A sample of 169 high-school students participated in the campaign. A questionnaire was administered to them before and 1 year after the campaign, asking for the frequency of discotheque attendance within the past 6 months, and whether they used earplugs in the discotheque. The percentage of subjects who went to discotheques more than 10 times within 6 months decreased from 34% to 24% after the campaign. The overall difference between pre- and post-campaign frequencies of discotheque attendance, however, was not significant. The percentage of subjects using earplugs in the discotheque rose from 0% before to 3.7% after the campaign. In essence, the campaign had little effect in inducing hearing-protective behaviour in adolescents when attending discotheques. The need for sound level limitations in discotheques is highlighted.

A model of peripherally developing hearing loss and tinnitus based on the role of hypoxia and ischemia

The incidence of sensorineural hearing loss often caused by direct damage to the cochlear hair cells is by far more frequent and more serious than disorders affecting the external ear or the middle ear. Mechanisms that are discussed to be relevant for the genesis of tinnitus and acquired hearing impairment are hair cell loss, signal transduction disturbances in the region of the outer and inner hair cells and the spiral ganglion, impairment of cochlear blood flow, mechanical disturbance, and hypoxia and ischemia. The present model surveys the possible cellular and molecular biological causes of peripherally developing hearing loss and tinnitus. In particular, the paper discusses the roles of hypoxia and ischemia in the cochlea and in the etiology of the neurosensory types of tinnitus. Peripheral origins of hearing disturbances and tinnitus may be: (a) damage to the stereocilia and the tip links, (b) dysfunction of potassium channels or (c) modification of the glutamate release. Moreover, the hypoxia inducible factor-1 may have an important role to play as a key transcription factor in the cells' adaptation to hypoxia and ischemia. An impairment of the cochlear blood flow may be induced by the expression of target genes like nitrogen monoxide synthase and endothelin-1 resulting in tinnitus. The paper discusses consequences resulting from the present model for the medical treatment of peripherally developing tinnitus and hearing loss.

Führt eine Schallpegelabsenkung in Diskotheken zu einem Rückgang der Besucher?

BACKGROUND

This study investigated whether adolescents are likely to decrease their frequency of discotheque attendance if the sound levels are lowered moderately.

METHODS

A sample of 1,213 high school students aged between 13 and 20 years (mean: 15.8 years) were given a questionnaire and asked their views on the current sound levels at discotheques, and whether they would change their attendance if the levels were somewhat lower.

RESULTS

Some 53.7% of the respondents wished to keep the current sound levels, while only 2.5% preferred a raise, and 43.8% a decrease. In the case of a moderate decrease, 85% of respondents would not change their frequency of discotheque attendance, while 5% would reduce it, and 10% would increase it.

CONCLUSIONS

The results of this study contradict the fears of discotheque operators that adolescents would visit the discotheque less frequently if the sound levels are lowered moderately. To prove the effects of a sound level reduction, however, separate studies are needed.

[Factors influencing rehabilitation of sensorineural hearing loss with hearing aids]

BACKGROUND

A large proportion of older as well as younger patients do not use their hearing aids. Of the younger hearing impaired population, this occurs in the majority of those who do not benefit sufficiently from their hearing aids and, consequently, they face difficulties in their working and social life.

SCIENTIFIC QUESTION

Our aim was to evaluate whether a classical hearing aid adjustment is of sufficient predictive value to determine whether adequate rehabilitation in everyday and professional life will occur.

METHODS AND RESULTS

A questionnaire was returned by 197 adult hearing impaired patients. Only 108 were using their hearing aids all the time; 57 rarely and 32 never. The main reason for this low rehabilitation rate proved to be inadequate amplification. At the workplace, insufficient speech discrimination came into play. Another important factor was dysacusis induced by specific noise signals. There was an intolerable acoustic feedback in 40% which could not be sufficiently alleviated. Taking these results into account, only about a third of patients were sufficiently rehabilitated.

CONCLUSIONS

Proof of effectiveness in a typical audiological testing situation is an important but not a fully reliable predictor for effectiveness in everyday life. Even when hearing aids are shown to be effective with such testing, their application in particular everyday or work situations may be insufficient of even impossible.

Influence of environmental factors on the evolution of industrial noise-induced hearing loss

The aim of the study is to investigate how environmental factors, associated with exposure to industrial noise, affect the development of chronic noise-induced hearing loss. The study was conducted on 186 male subjects working in two bottling plants, situated respectively in a small farming community, and in a medium-sized city with significant levels of noise pollution. Levels of occupational exposure were the same for the two groups. The subjects were selected by means of a preliminary medical examination, and exposed to tonal hearing tests and acoustic impedance tests. Statistical analysis was performed on hearing threshold values obtained at the frequencies of 500, 1000, 2000 and 4000 Hz. The comparison between the thresholds obtained in the two groups showed a statistically significant difference, especially at the frequency of 4000 Hz and for occupational exposure exceeding 17 yr. The results led us to conclude that environmental factors, and urban noise in particular, influence the onset and development of occupational acoustic trauma, and that those working in the country are significantly less affected than those in the city. Since occupational exposure was the same for both groups, their different responses must therefore be interpreted as due to differences in non-occupational exposure, in turn dependent on different opportunities for rest from noise and different levels of exposure to noise pollution.

[Inner ear damage due to leisure and broadband noise. An experimental study on initial and permanent functional and morphological damage]

The initial and permanent effects of leisure noise (toy pistols, rock music) compared to broadband noise were examined in 68 guinea pigs. Auditory threshold shifts at 1.5, 2, 3, 4, 6, 8, 12 und 16 kHz were registered before and immediately after exposure as well as on days 1, 2, 3, 5,7 and 21 post-exposure using the auditory brain stem response (ABR) technique. In order to examine cilia and hair cell damage in eight cochlear frequency regions (<0,4 kHz, 0,4-0,8 kHz, 0,8-1.5 kHz, 1.5-3 kHz, 3-5 kHz, 5-11.5 kHz, 11.5-26 kHz und >26 kHz), cytocochleograms were performed immediately after exposure and on days 1, 7 and 21.Frequency dependent functional or morphological damage was found which depended on the type of trauma tested. All results were highly significant ( P<0.001). The results show that partial recovery of hearing occurred within 3 days of acute acoustic trauma induced by toy pistols and within 1 day after exposure to rock music or broadband noise. There was no further recovery of hearing within the following 18 and 20 days, respectively. Furthermore, permanent threshold shifts after exposure to rock music or broadband noise were not associated with cilia and/or hair cell damage.

Rapid recovery from acoustic trauma: chicken soup, potato knish, or drug interaction?

OBJECTIVES

To describe the phenomenology and consider possible mechanisms mediating rapid and unexpected recovery from acoustic trauma after ingestion of a food substance (potato knish).

STUDY DESIGN

Single subject with repeated test measures.

SETTING

Regional Veteran's Administration Medical Center, tertiary care medical center.

METHODS

Pure-tone audiometry and distortion product otoacoustic emissions (DPOAEs) performed at 6 days, 21 days, and 1 year postexposure.

RESULTS

Medical treatment with corticosteriods and a diuretic alone failed to improve auditory function and related symptoms (tinnitus and aural fullness) over a 2-week period. Rapid recovery of auditory function (dramatic improvement in pure tone thresholds; reappearance of DPOAEs) and abatement of related symptoms directly followed physiologic reactions from ingesting a food substance.

CONCLUSIONS

Rapid recovery from acoustic trauma was temporally correlated with urodynamic and cardiovascular reactions from ingesting food containing sulfite preservative, a substance to which the individual was allergic. Factors that may have contributed to recovery of function include massive diuresis, increased heart rate, release of biochemical mediators, mediator-induced vasodilatation, and changes in vascular or cell membrane permeability. Establishing relationships that lead to recovery of function from acoustic trauma may facilitate research and aid in the development of new treatment options for this condition.