The effect of air-bone gap observed at high frequencies on wide band tympanometry and dpoae responses in geriatrics

Some anatomical, histological, and physiological changes occur in the external and middle ear depending on aging. In this study, we investigated the wideband tympanometry results of elderly people and different old age groups and looked for the relationships of the wideband tympanometry results of elderly people with behavioral and electrophysiological (distortion-product otoacoustic emission) test results. In this context, 34 individuals over the age of 65 (60 old ears) were investigated in three subgroups according to the following age groups: Youngest-old (65-74 years), middle-old (75-84 years), and oldest-old (≥85 years). We found that there was a significant difference between the old and young groups for all assessment parameters of the wideband tympanometry measurements (p<0.05). Regarding the elderly subgroups, contrary to expectations, we determined a significant inverse correlation in high-frequency absorbance values in the oldest-old group (p<0.05). In elderly people, we found also a moderate positive correlation between the wideband tympanometry test results and behavioral audiometry and distortion-product otoacoustic emission tests in certain high-frequency fields. The findings obtained in this study showed that the middle-ear transfer of sound functions was more affected in the high-frequency range in the geriatric population and therefore we conclude that the high-frequency sound of transfer characteristics should be taken into consideration during the audiological examination. In addition, the study results indicated that the wideband tympanometry results and behavioral audiometry and DPOAE test results may be used to cross-check in the audiological assessments in elderly people.