Representative epidemiologic data on the average volume of the parotid gland in a large population-based MRI survey is non-existent. Within the Study of Health in Pomerania (SHIP), we examined the parotid gland in 1725 non-contrast MRI-scans in T1 weighted sequence of axial layers. Thus, a reliable standard operating procedure (Intraclass Correlation Coefficient > 0.8) could be established. In this study, we found an average, single sided parotid gland volume of 27.82 cm³ (95% confidence interval (CI) 27.15 to 28.50) in male and 21.60 cm³ (95% CI 21.16 to 22.05) in female subjects. We observed positive associations for age, body mass index (BMI), as well as male sex with parotid gland size in a multivariate model. The prevalence of incidental tumors within the parotid gland regardless of dignity was 3.94% in the Northeast German population, slightly higher than assumed. Further epidemiologic investigations regarding primary salivary gland diseases are necessary.

Background: By using outcome prediction scores, it is possible to distinguish between good and poor performers with cochlear implants (CI) after CI implantation. The reasons for poor performance, despite good basic conditions, can be manifold. On the one hand, the postoperative fitting may be inadequate; on the other, neurophysiological disease processes may impair speech understanding with a CI. These disease processes are not yet fully understood. In acoustics, it is known that the auditory brainstem responses (ABR) and their latencies and amplitudes allow differential diagnosis based on reference values for normal-hearing individuals. The aim of this study was to provide reference values for electrically evoked brainstem responses (EABRs) in terms of rate-dependent latencies and amplitudes. Methods: 20 ears of 18 experienced adult CI recipients with a predicted and measured good postoperative word recognition score were recruited from the clinic’s patient pool. In the same stimulation mode and intensity we measured latencies and interpeak-latencies of EABRs and electrically evoked compound action potentials (ECAPs). With a defined supra-threshold stimulation intensity above the individual ECAP threshold, we applied stimulation at several rates between 11 and 91 stimuli per second. Results: We found rate dependences for EABR latency t3 and t5 in the order of 0.19 ms and 0.37 ms, respectively, while ECAP was not affected by rate. Correspondingly, the interpeak intervals’ rate dependences for $\mathrm{t}5-\mathrm{t}1$, $\mathrm{t}5-\mathrm{t}3$ and $\mathrm{t}3-\mathrm{t}1$ were of the order of 0.37 ms, 0.18 ms and 0.19 ms. Comparing the EABR amplitudes between the stimulation rates 11/s and 81/s, we found that at 81/s the amplitudes were significantly reduced down: to 73% for A3 and 81% for A5. These rate dependences of latency and amplitude in EABR have characteristics comparable to those of acoustic ABR. Conclusions: These data may serve to provide reference values for EABR and ECAP latencies, interpeak intervals and amplitudes with respect to stimulation rate. Altered response patterns of ECAPs and EABRs to normalised stimulation modes could be used in the future to describe and classify neuropathological processes in a better-differentiated way.

Background/Objectives: Menière’s disease (MD) is a debilitating disorder with episodic and variable ear symptoms. Diagnosis can be challenging, and evidence for therapeutic approaches is low. Furthermore, patients show a unique and fluctuating configuration of audiovestibular impairment. As a psychometric instrument to assess hearing-specific disability is currently lacking, we evaluated a short form of the Speech, Spatial, and Qualities of Hearing Scale (SSQ) in a cohort of patients with MD. Methods: Data was collected in the context of a multicenter prospective patient registry intended for the long-term follow up of MD patients. Hearing was assessed by pure tone and speech audiometry. The SSQ was applied in the German language version with 17 items. Results: In total, 97 consecutive patients with unilateral MD with a mean age of 56.2 ± 5.0 years were included. A total of 55 individuals (57.3%) were female, and 72 (75.0%) were categorized as having definite MD. The average total score of the SSQ was 6.0 ± 2.1. Cronbach’s alpha for internal consistency was 0.960 for the total score. We did not observe undue floor or ceiling effects. SSQ values showed a statistically negative correlation with hearing thresholds and a statistically positive correlation with speech recognition scores of affected ears. Conclusions: The short form of the SSQ provides insight into hearing-specific disability in patients with MD. Therefore, it may be informative regarding disease stage and rehabilitation needs.

Background: Hearing loss is a major, potentially modifiable risk factor for dementia and often co-occurs with tinnitus. Both conditions are prevalent and have been linked to cognitive decline and brain health. However, evidence from large population-based studies remains limited. Therefore, this study investigated associations of hearing loss and tinnitus with cognitive performance and brain structure in a large cohort from northeastern Germany.Methods: Data from the baseline investigation of 4420 participants (age 20-84 years) of the SHIP-TREND cohort was analysed. Thereof, 4400 completed a self-assessment for hearing and 3937 for tinnitus. Cognitive performance was assessed by tests on verbal memory and executive function. T1-weighted MRI yielded data on global and regional volumes and cortical thickness for 2144 participants. Multiple linear regression and mediation analyses were conducted, adjusted for age, sex, and further risk factors for dementia.Findings: A total of 1455 participants reported hearing loss, 679 thereof a clinically relevant degree and 874 participants reported tinnitus. Hearing loss was associated with worse memory performance and unfavourable brain measures, particularly along the central auditory pathway and in regions implicated in cognitive function and Alzheimer’s Disease. Notably, white matter hypointensity volume partially mediated (8.8%) the association of hearing loss with immediate recall performance. Hearing loss was associated with tinnitus (odds ratio 7.5 [95%CI 6.0 to 9.3]; p<0.001), but no relevant combined effects on cognitive performance or brain measures were observed, and tinnitus alone was not associated with cognition or adverse brain measures.Interpretation: This large cohort study not only confirmed independent associations of self-reported hearing loss with memory performance and structural brain measures but also suggested a pathophysiologic link between hearing loss and cerebrovascular disease. Our findings support hearing loss, but not tinnitus, as a modifiable contributor to cognitive decline and dementia, highlighting it as a key target for early prevention strategies.

BACKGROUND: Menière’s Disease (MD) is a debilitating disorder with episodic and variable ear symptoms. Diagnosis can be challenging and there is no current consensus regarding monitoring of disease progression. A psychometric instrument may aid the assessment of subjective hearing impairment and the associated burden in daily life over the course of the disease. However, evidence in this regard is lacking. OBJECTIVE: To evaluate a German-language short form of the Speech, Spatial and Qualities of Hearing Scale (SSQ) for hearing-related disability in MD. METHODS: Data was collected from a multicenter prospective patient registry for long-term follow up of MD patients. Hearing was assessed by pure tone and speech audiometry. The applied version of the SSQ contained 17 items. RESULTS: 97 consecutive patients with unilateral MD had a mean age of 56.2 ± 5.0 years. 55 individuals (57.3%) were female, 72 (75.0%) were categorized as definite MD. Average total score of the SSQ was 6.0 ± 2.1. Cronbach’s alpha for internal consistency was 0.960 for the total score. We did not observe undue floor or ceiling effects. SSQ values showed a negative correlation with hearing thresholds and a positive correlation with speech recognition scores. CONCLUSIONS: The short form of the SSQ provides insight into hearing-specific disability in patients with MD. Thereby, it may be informative regarding disease stage and rehabilitation needs.

Objectives The senses of hearing and balance are linked by a close anatomical and physiological relationship. A further pathophysiological interaction is supposed but the detailed mechanism and direction remains elusive. Further insight is required into the prevalence of the audiovestibular symptoms hearing loss, tinnitus and dizziness as only scarce information on the combined occurrence is available so far. Therefore, this was assessed in a population-based sample. Based on this, we studied the influence of risk factors from lifestyle habits as well as cardiovascular and metabolic conditions on the development of audiovestibular symptoms alone and in combination. Design This analysis evaluated the prevalence of self-reported hearing loss, tinnitus and dizziness in two separate population-based samples from West Pomerania, a rural region of north-eastern Germany. Datasets from 8134 individuals aged 20 to 79 years were available from the baseline investigations of the cohorts START and TREND of the Study of Health in Pomerania (SHIP). Audiovestibular symptoms were assessed by structured questionnaires. The cohorts were comprehensively characterized regarding modifiable lifestyle factors as well as cardiovascular and metabolic disorders, allowing the assessment of the role of those influencing factors. Results Audiovestibular symptoms were prevalent and overlapping in the investigated population. 2350 individuals (28.9%) reported at least one, 648 (8.1%) two and 111 (1.4%) all three audiovestibular symptoms. Thereby, we observed a weighted prevalence of 14.2% for hearing loss, 9.7% for tinnitus and 13.5% for dizziness in the population. The prevalences increased with age and differed among the sexes. The prevalence of hearing loss as well as tinnitus increased between the two cohorts. A moderate positive correlation was found between hearing loss and tinnitus (phi-coefficient 0.318). In multivariable regression analyses, only smoking was significantly associated with all three symptoms. Less education and several cardiovascular risk factors contributed to both hearing loss and dizziness. Conclusions Audiovestibular symptoms are highly prevalent in the general population and the occurrence overlaps. A considerable but complex influence of risk factors points towards a relation with neuronal as well as cardiovascular disease processes. Future studies should identify subgroups that are particularly at risk. Additionally, to clarify the underlying mechanisms the interaction between the senses of hearing and balance as well as the mode of action of the risk factors should be evaluated in more detail in the future.