Biomedical subjects

Niels Christian Stenklev

Publications and source records attributed to Niels Christian Stenklev.

4 recordsLinked to original sources

PubMed2004

The aging ear: an otomicroscopic and tympanometric study.

OBJECTIVES: To analyze changes in tympanometric measures with age and to study some otitis-related issues in the elderly (> or = 60 years) population. MATERIAL AND METHODS: The study was designed as a combination of a cross-sectional survey and a controlled study. We studied a random sample of 232 elderly subjects using an extended battery of audiological tests, including pure-tone audiometry. tympanometry with a probe frequency of 226 Hz, otomicroscopy and a standardized questionnaire. A sample of 60 otologically normal subjects were selected for comparative analysis with young healthy controls, and for description of age-related changes and gender differences. RESULTS: Using linear regression analyses of ear canal volume, middle ear pressure and tympanic membrane compliance on age, no consistently significant change in these parameters with age was found. When these measures were compared between the elderly and the controls, using parametric and non-parametric statistical tests, no significant differences were found for either gender. The only significant gender difference was found for ear canal volume, which was greater for elderly males than for elderly females In the unscreened elderly sample, the adjusted prevalence for reported previous or current otitis media was 15-27% of the population (95% CI). The adjusted prevalence for reported previous or current chronic otitis media (COM) or sequelae thereof was 1-7% (95% CI). With the exception of cerumen obstruction, the prevalence of outer ear canal-related complaints was 1-7% (95% CI). There were some discrepancies between these reported complaints and the findings at otomicroscopy. Although elderly subjects with COM were found to have poorer hearing at speech frequencies than normal elderly subjects. no such effect was found in subjects with scarring or atrophy of the tympanic membrane. The effect of pathological findings at otomicroscopy on tympanometric measures in the elderly sample was highly variable and no consistent association was found. CONCLUSIONS: No change in middle ear sound transmission, as assessed by tympanometry, occurs with normal aging. Ear canal volume is smaller in elderly females than elderly males, which is potentially relevant to the study of otoacoustic emissions in the elderly. The estimated prevalence of ear canal-related problems, excluding cerumen obstruction, is of such a magnitude that the introduction of partially implanted hearing aids may be warranted in our elderly population.

Acoustic Impedance Tests↗

PubMed2004

Presbyacusis-hearing thresholds and the ISO 7029.

The purpose of this study was to analyse the changes in pure-tone hearing thresholds with age. We studied a random sample of 232 elderly subjects with a battery of audiological tests, including pure-tone audiometry in the conventional and extended high-frequency range, using the normative distributions from the International Organization for Standardization (ISO) standard 7029 for comparison. Sixty otologically normal (ON) subjects were selected for comparative analysis with the unscreened (US) sample, and for description of gender and age group differences. With the use of a mathematical transformation of threshold data, it was found that the ISO 7029 normative alpha coefficient in females may be set too low compared to our sample in the lower frequencies, leading to an underestimation of hearing thresholds in ON females. In our ON sample, hearing thresholds deteriorated with age in the extended high-frequency audiometric range. No gender threshold differences were found, although the prevalence of unmeasurable responses was higher in males at some of these frequencies. The ON screening criteria in ISO 7029 may be unreliable in subjects over 60 years of age, as threshold differences between ON and US subjects were not consistent at any frequency.

Age Factors↗

PubMed2004

Cortical cognitive potentials in elderly persons.

The purpose of this study was to analyze the changes in the acoustically evoked cortical cognitive potentials N 200, P 300, and N 3 with age. There were 232 participants, who were 60 years or older, and each was examined using a battery of audiological tests including a questionnaire, otomicroscopy, pure-tone audiometry, and cortical cognitive potentials, measured at Fz using an auditory oddball paradigm. N 200 was elicited in 46.9%, P 300 in 45.1%, and N 3 in 52.2% of the elderly participants. The most significant predictors for presence of cortical responses were the participant's age and hearing level at target tone frequency. Monosyllabic speech recognition score was a less important predictor for presence of response. Response latency in the elderly sample increased steadily with age. Few changes in cortical response amplitude were found with age. We conclude that the speed of central auditory processing seems to be reduced with age.

Adult↗

PubMed2003

Transient evoked otoacoustic emissions in the elderly.

The purpose of this study was to analyse the changes in transient evoked otoacoustic emissions (TEOAEs) with age. We studied 232 subjects above 60 years of age with a battery of audiological tests, including TEOAEs Our criterion for the presence of TEOAEs was based on a cut-off at overall wave reproducibility 55% or overall response level 4 dB SPL. The prevalence of TEOAEs in left ears was 55.6%. No TEOAEs were found in subjects with a pure-tone average (PTA) above 40 dB HL. In the subgroup with TEOAEs, a significant decrease in overall wave reproducibility with age was found. We compared 45 normal-hearing elderly subjects with TEOAEs with a control group of 20 normal-hearing young adults The elderly had significantly lower mean overall response levels and mean overall wave reproducibility. Average hearing level was significantly higher in the elderly than in controls We conclude that the prevalence of TEOAEs decreases with age, and that the overall response level and overall reproducibility decrease with age. This decrease may not be seen in isolation from the increase in hearing threshold level.

Acoustic Stimulation↗