Evidence of Vestibular and Balance Dysfunction in Patients With Mild Cognitive Impairment and Alzheimer's Disease.

OBJECTIVES: Given the expected rise in dementia prevalence, early diagnosis is vital. As a growing body of literature has identified a potential association between vestibular function and cognition, vestibular assessment may aid in early screening. The aim of the study was to better comprehend the proposed association between vestibular function and Alzheimer's disease (AD) by comparing vestibular parameters (vestibular function testing and clinical balance measures) between a group with mild cognitive impairment (MCI), AD, and healthy controls with age-normal cognition. DESIGN: Cross-sectional analysis of the GECkO study, an ongoing prospective single-center longitudinal cohort study. This study included 100 older adults (55 to 84 years). A total of 33 participants with MCI, 17 participants with AD, and 50 participants of age, sex, and hearing-matched healthy controls were included. RESULTS: Participants with AD demonstrated a delayed latency of the p13 component measured by cervical vestibular-evoked myogenic potentials (cVEMP) compared with healthy controls and participants with MCI. Other measures including n23 latency, presence of intact responses, rectified amplitude, mean rectified voltage (measured by cVEMP) and lateral vestibulo-ocular reflex gain (measured by video Head Impulse Test [vHIT]) did not differ between groups. The Timed Up and Go (TUG), Performance-Oriented Mobility Assessment-Balance subscale (POMA-B), and Functional Gait Assessment (FGA) differed significantly between the three groups. Here, more cognitively impaired groups were associated with worse clinical balance scores. CONCLUSIONS: Vestibular and balance deficits were more prevalent in groups with increasing cognitive decline. Regarding vestibular function testing, p13 latency as measured by cVEMP was delayed in participants with AD. Other cVEMP or vHIT measures did not differ between groups. All three clinical balance assessments (TUG, POMA-B, and FGA) resulted in worse scores along the AD continuum. Future research integrating vestibular parameters that add value (including otolith function testing, balance, and spatial navigation) is recommended to validate the association between vestibular function and cognition while avoiding redundant testing.

International Consensus Statements on Intraoperative Testing for Cochlear Implantation Surgery.

OBJECTIVES: A wide variety of intraoperative tests are available in cochlear implantation. However, no consensus exists on which tests constitute the minimum necessary battery. We assembled an international panel of clinical experts to develop, refine, and vote upon a set of core consensus statements. DESIGN: A literature review was used to identify intraoperative tests currently used in the field and draft a set of provisional statements. For statement evaluation and refinement, we used a modified Delphi consensus panel structure. Multiple interactive rounds of voting, evaluation, and feedback were conducted to achieve convergence. RESULTS: Twenty-nine provisional statements were included in the original draft. In the first voting round, consensus was reached on 15 statements. Of the 14 statements that did not reach consensus, 12 were revised based on feedback provided by the expert practitioners, and 2 were eliminated. In the second voting round, 10 of the 12 revised statements reached a consensus. The two statements which did not achieve consensus were further revised and subjected to a third voting round. However, both statements failed to achieve consensus in the third round. In addition, during the final revision, one more statement was decided to be deleted due to overlap with another modified statement. CONCLUSIONS: A final core set of 24 consensus statements was generated, covering wide areas of intraoperative testing during CI surgery. These statements may provide utility as evidence-based guidelines to improve quality and achieve uniformity of surgical practice.

The effect of anxiety and depression on cognition in older adults with severe-to-profound hearing loss.

PURPOSE: To evaluate the effect of anxiety and/or depression on cognition in older adults with severe-to-profound hearing loss. METHODOLOGY: In total, 83 older subjects (age of 55 years or older) with post-lingual, bilateral, severe-to-profound hearing loss were enrolled in this study between April 2014 and March 2021. The Repeatable Battery for Assessment of Neuropsychological Status for Hearing-impaired individuals (RBANS-H) and the Hospital Anxiety and Depression Scale (HADS) were used to measure cognition and anxiety/depression. RESULTS: A multiple linear regression was used to predict the total RBANS-H score based on the total HADS score, years of education and age of the participants. These variables statistically significantly predicted RBANS-H, F(3, 79) = 12.604, p = 0.010, R2 = 0.324. All three variables added statistically significantly to the prediction, p < 0.05. A higher HADS-score resulted in a significantly lower RBANS-H score with an estimated effect size b1 of - 0.486. In addition, a multiple linear regression was executed for each subdomain of the RBANS-H and its relation to the total HADS-score, age and years of education of the participants. These variables statistically significantly predicted RBANS-H immediate memory F(3, 79) = 16.858, p = 0.003, R2 = 0.390. All three variables added statistically significantly to the prediction, p < 0.05. In the other four subdomains no statistical significance was observed. CONCLUSIONS: Anxiety and/or depression have a significantly negative impact on cognition in individuals with severe-to-profound hearing loss. This negative correlation was mainly attributable to the significantly lower score in the immediate memory subdomain.

Tinnitus suppression by means of cochlear implantation: does it affect cognition?

PURPOSE: Recent literature suggests that tinnitus can impact cognition, but results were varied due to a diversity in investigated aspects of cognition and utilized tests, as well as the possible influence of confounding factors. The purpose of this study was to assess the impact of tinnitus loudness on cognition by use of a within-subjects design in patients with a cochlear implant (CI). In this population, tinnitus loudness can be modulated by switching the CI on or off as CI is known to highly suppress tinnitus. METHODS: A total of 18 CI users completed two versions of the Repeatable Battery for Assessment of Neuropsychological Status for Hearing Impaired individuals (RBANS-H), once in unaided condition and once in best aided condition. Tinnitus suppression was defined as a difference in score on a visual-analogue scale (VAS) of at least one point out of ten between these two conditions. RESULTS: No significant differences in RBANS-H scores were found between the suppression and no suppression group, nor for the suppression group alone. No significant correlations between tinnitus loudness and RBANS-H were found, neither for the suppression group alone, nor for the group as a whole. CONCLUSION: The current study shows no significant effect of tinnitus loudness on cognition, which contradicts previous literature. This discrepancy could be explained by the use of a within-subjects design, which controls for confounding factors. Future research should include a larger and more diverse study sample to draw definitive conclusions on this topic.

Holistic assessment of cochlear implant outcomes using the international classification of functioning disability and health model: data analysis of a longitudinal prospective multicenter study.

PURPOSE: To study outcome after cochlear implantation using the Cochlear Implant (CI) outcome assessment protocol based on the International Classification of Functioning, Disability and Health (ICF) model (CI-ICF). METHODS: Raw data of a prospective, longitudinal, multicenter study was analyzed. Seventy-two CI candidates were assessed preoperatively and six months postoperatively using the CI-ICF protocol. Following tools were used: (1) Work Rehabilitation Questionnaire (WORQ), (2) Abbreviated Profile of Hearing Aid Benefit (APHAB), (3) Audio Processor Satisfaction Questionnaire (APSQ), (4) Speech, Spatial, and Qualities of Hearing Scale (SSQ12), (5) Hearing Implant Sound Quality Index (HISQUI19), (6) Nijmegen CI Questionnaire (NCIQ) (7) pure tone audiometry, (8) speech audiometry, (9) sound localization. RESULTS: There was a significant improvement of speech discrimination in quiet (p = 0.015; p < 0.001) and in noise (p = 0.041; p < 0.001), sound detection (p < 0.001), tinnitus (p = 0.026), listening (p < 0.001), communicating with-receiving-spoken messages (p < 0.001), conversation (p < 0.001), family relationships (p < 0.001), community life (p = 0.019), NCIQ total score and all subdomain scores (p < 0.001). Subjective sound localization significantly improved (p < 0.001), while psychometric sound localization did not. There was no significant subjective deterioration of vestibular functioning and no substantial change in sound aversiveness. CI users reported a high level of implant satisfaction postoperatively. CONCLUSION: This study highlights the positive impact of cochlear implantation on auditory performance, communication, and subjective well-being. The CI-ICF protocol provides a holistic and comprehensive view of the evolution of CI outcomes.

Dual-site transcranial direct current stimulation to treat tinnitus: a randomized controlled trial.

Transcranial direct current stimulation (tDCS) has been proposed as a potential intervention for subjective tinnitus, but supporting evidence remains limited. We aimed to investigate the effect of anodal high-definition tDCS of the left temporal area and right dorsolateral prefrontal cortex on tinnitus severity. This double-blind randomized controlled trial included 77 patients (age range 18-79, 43 male) with chronic subjective tinnitus as their primary complaint. Thirty-eight subjects received six consecutive sessions of dual-site sequential high-definition-tDCS with electrodes positioned over the left temporal area and right dorsolateral prefrontal cortex. Both areas were stimulated for 15 min per session, with total stimulation time amounting to 30 min. Thirty-nine subjects received sham stimulation. The primary outcome measure was the change in tinnitus severity, as evaluated by the Tinnitus Functional Index, from baseline to a follow-up visit at 8 ± 2 weeks after treatment completion. Secondary outcomes included changes in perceived tinnitus loudness, as measured with a visual analogue scale and a tinnitus matching procedure, as well as scores on the Hospital Anxiety and Depression Scale, and the Hyperacusis Questionnaire. No differences in Tinnitus Functional Index change scores were identified between the active treatment and sham control groups (linear regression: P = 0.86). The Tinnitus Functional Index scores decreased significantly over time in both groups (P = 0.0012), indicating the presence of a considerable placebo effect. These change scores were significantly influenced by sex (linear regression: P = 0.037) and baseline symptoms of anxiety (linear regression: P = 0.049) in both groups. In general, Tinnitus Functional Index scores decreased more profoundly in males and in subjects with a higher degree of anxiety at baseline. None of the included secondary measures differed significantly between experimental arms. Our results suggest that dual-site sequential high-definition-tDCS of the left temporal area and right dorsolateral prefrontal cortex does not alleviate tinnitus severity. Interestingly, in our study population, fluctuations in tinnitus severity were influenced by gender and concurrent mental condition. It is therefore important to take these factors into account when conducting or planning randomized controlled trials in tinnitus populations.

Accelerated Cognitive Decline Associated With Hearing Loss and Bilateral Vestibulopathy: Insights From a Prospective Cross-Sectional Study Using the Repeatable Battery for the Assessment of Neuropsychological Status Adjusted for the Hearing Impaired in the DFNA9 Population.

BACKGROUND: DeaFNess Autosomal dominant 9 (DFNA9) is a hereditary disorder known to affect both hearing and vestibular function in its carriers. Its phenotype is characterized by progressive sensorineural hearing loss (SNHL) and vestibular dysfunction evolving towards bilateral vestibulopathy (BV) by the 3rd to 5th life decade. Recent studies have identified the impact of hearing loss and vestibular dysfunction on cognitive functioning. OBJECTIVE: The main objective of this study was to investigate how the cognitive functioning of carriers of the p.Pro51Ser variant in the COCH gene is affected by the disease and compare these results with a matched healthy control group. STUDY DESIGN: Forty-six carriers of the pathogenic p.Pro51Ser variant in the COCH gene were included in this study, of which 38 met the Bárány Society criteria and were thus diagnosed with BV. All subjects were between the age of 22 and 72 years old. Each control was individually matched based on age, gender, and education level. A cognitive, vestibular, and hearing assessment was performed in all subjects. All participants completed the Repeatable Battery for the Assessment of Neuropsychological Status, adjusted for the Hearing Impaired (RBANS-H), a cognitive test battery that includes subtests probing Immediate and Delayed Memory, Visuospatial/Constructional, Language, and Attention. RESULTS: Overall, the DFNA9 patients demonstrated significantly lower scores on the Immediate Memory subscale and lower Total Scale scores than their healthy matched controls. The total sample was divided into two groups: age <55 years old and age ≥55 years old. The DFNA9 group aged ≥55 years old obtained significantly lower scores on the Attention subscale and lower Total Scale scores than their matched controls. Cognition of DFNA9 patients aged <55 years old no longer differed significantly from their matched controls. CONCLUSION: This cross-sectional study found that DFNA9 patients demonstrated cognitive deficits in comparison with their healthy matched controls. The DFNA9 group aged ≥ 55 years old obtained significantly lower scores on the Total Scale and Attention subscale. This finding; however, was not observed for the age group younger than 55 years old. Further research is needed on the individual trajectory of SNHL and vestibular function, and how hearing rehabilitation affects cognitive functioning.

Audiological outcomes of robot-assisted cochlear implant surgery.

PURPOSE: The main objective of this study is to evaluate the short-term and long-term audiological outcomes in patients who underwent cochlear implantation with a robot-assisted system to enable access to the cochlea, and to compare outcomes with a matched control group of patients who underwent cochlear implantation with conventional access to the cochlea. METHODS: In total, 23 patients were implanted by robot-assisted cochlear implant surgery (RACIS). To evaluate the effectiveness of robotic surgery in terms of audiological outcomes, a statistically balanced control group of conventionally implanted patients was created. Minimal outcome measures (MOM), consisting of pure-tone audiometry, speech understanding in quiet and speech understanding in noise were performed pre-operatively and at 3 months, 6 months, 12 months and 2 years post-activation of the audioprocessor. RESULTS: There was no statistically significant difference in pure-tone audiometry, speech perception in quiet and speech perception in noise between robotically implanted and conventionally implanted patients pre-operatively, 3 months, 6 months, 12 months and 2 years post-activation. A significant improvement in pure-tone hearing thresholds, speech understanding in quiet and speech understanding in noise with the cochlear implant has been quantified as of the first measurements at 3 months and this significant improvement remained stable over a time period of 2 years for HEARO implanted patients. CONCLUSION: Clinical outcomes in robot-assisted cochlear implant surgery are comparable to conventional cochlear implantation. CLINICALTRAILS. GOV TRAIL REGISTRATION NUMBERS: NCT03746613 (date of registration: 19/11/2018), NCT04102215 (date of registration: 25/09/2019).

Contralateral hearing aid use in adult cochlear implant recipients: retrospective analysis of auditory outcomes.

OBJECTIVE: To investigate retrospectively the frequency of usage of bimodal stimulation among cochlear implant (CI) users, as well its clinical benefit relative to unilateral use. DESIGN: All subjects had been monitored with the clinical Minimal Outcome Measurements test battery. STUDY SAMPLES: 103 adults with bilateral postlingual profound sensorineural hearing loss and unilateral CI use were extracted from the local database. These were divided into two groups: those who only used a CI and those who used bimodal stimulation. RESULTS: The preoperative contralateral residual hearing in the bimodal group was significantly better than that of the CI-only group. In both groups, speech perception in quiet and in noise improved after CI, with no significant difference between postoperative unimodal conditions. For the bimodal group, an additional significant improvement was found for the bimodal condition compared to the unimodal. CONCLUSION: Given the observed auditory benefit of bimodal stimulation in comparison to unimodal stimulation and given the finding that degree of residual hearing is not correlated with bimodal benefits, it is recommended to encourage CI recipients to continue contralateral HA use after CI. As a result of expanding CI criteria worldwide, the population of bimodal users is expected to grow in the near future.

Random Forest Classification to Predict Response to High-Definition Transcranial Direct Current Stimulation for Tinnitus Relief: A Preliminary Feasibility Study.

OBJECTIVES: Transcranial direct current stimulation (tDCS) of the right dorsolateral prefrontal cortex has been hypothesized to reduce tinnitus severity by modifying cortical activity in brain regions associated with the perception of tinnitus. However, individual response to tDCS has proven to be variable. We investigated the feasibility of using random forest classification to predict the response to high-definition (HD) tDCS for tinnitus relief. DESIGN: A retrospective analysis was performed on a dataset consisting of 99 patients with subjective tinnitus receiving six consecutive sessions of HD-tDCS at the Antwerp University Hospital. A baseline assessment consisted of pure-tone audiometry and a set of questionnaires including the Tinnitus Functional Index (TFI), Hospital Anxiety and Depression Scale, and Edinburgh Handedness Inventory. Random forest classification was applied to predict, based on baseline questionnaire scores and hearing levels, whether each individual responded positively to the treatment (defined as a decrease of at least 13 points on the TFI). Further testing of the model was performed on an independent cohort of 32 patients obtained from the tinnitus center at the University of Regensburg. RESULTS: Twenty-four participants responded positively to the HD-tDCS treatment. The random forest classifier predicted treatment response with an accuracy of 85.71% (100% sensitivity, 81.48% specificity), significantly outperforming a more traditional logistic regression approach. Performance of the classifier on an independent cohort was slightly but not significantly above chance level (71.88% accuracy, 66.67% sensitivity, 73.08% specificity). Feature importance analyses revealed that baseline tinnitus severity, co-occurrence of depressive symptoms and handedness were the most important predictors of treatment response. Baseline TFI scores were significantly higher in responders than in nonresponders. CONCLUSIONS: The proposed random forest classifier predicted treatment response with a high accuracy, significantly outperforming a more traditional statistical approach. Machine learning methods to predict treatment response might ultimately be used in a clinical setting to guide targeted treatment recommendations for individual tinnitus patients.

The smaller the frequency-to-place mismatch the better the hearing outcomes in cochlear implant recipients?

OBJECTIVE: To investigate the effect of frequency-to-place mismatch, i.e. the mismatch between the tonotopic frequency map in the cochlea and the frequency band that is assigned to an electrode contact of a cochlear implant (CI) at the same cochlear location on speech perception outcomes, using postoperative CT images. STUDY DESIGN: Retrospective observational single-centre study. METHODS: Retrospective pre- and postoperative clinical CT data of 39 CI recipients with normal cochlear anatomy were analysed in an otological surgical planning software. The tonotopic frequency at each electrode position was estimated using the Greenwood function. For each patient, frequency-to-place mismatch between the tonotopic frequency and the fitted centre frequency for each electrode contact was calculated. The influence of frequency-to-place mismatch on speech perception in noise at 6 and 12 months after CI activation was studied. RESULTS: A significant linear correlation was found between the frequency-to-place mismatch and speech perception in noise 6 months after cochlear implantation (p < 0.05). The smaller the frequency-to-place mismatch, the better the initial speech perception in noise results of the CI recipients. The significant effect disappeared after 12 months CI experience. CONCLUSION: The study findings support the idea of minimizing the frequency-to-place mismatch in CI recipients in order to pursue better initial speech perception in noise. Further research is needed to investigate the prospect of tonotopic fitting strategies based upon postoperative CT images of the exact locations of the electrode contacts.

The impact of cochlear implantation on health-related quality of life in older adults, measured with the Health Utilities Index Mark 2 and Mark 3.

PURPOSE: To determine the usefulness of the Health Utilities Index (HUI) in older cochlear implant (CI) recipients, the primary aims were: (1) to assess health-related quality of life (HRQoL), measured with HUI, in older CI candidates while comparing with age- and gender-matched normal-hearing controls; (2) to compare HRQoL after CI with the pre-operative situation, using HUI and the Nijmegen cochlear implant questionnaire (NCIQ). The difference between pre- and postoperative speech intelligibility in noise (SPIN) and in quiet (SPIQ) and the influence of pre-operative vestibular function on HRQoL in CI users were also studied. METHODS: Twenty CI users aged 55 years and older with bilateral severe-to-profound postlingual sensorineural hearing loss and an age- and gender-matched normal-hearing control group were included. HRQoL was assessed with HUI Mark 2 (HUI2), HUI Mark 3 (HUI3) and NCIQ. The CI recipients were evaluated pre-operatively and 12 months postoperatively. RESULTS: HUI3 Hearing (p = 0.02), SPIQ (p < 0.001), SPIN (p < 0.001) and NCIQ (p = 0.001) scores improved significantly comparing pre- and postoperative measurements in the CI group. No significant improvement was found comparing pre- and postoperative HUI3 Multi-Attribute scores (p = 0.07). The HUI3 Multi-Attribute score after CI remained significantly worse (p < 0.001) than those of the control group. Vestibular loss was significantly related to a decrease in HUI3 Multi-Attribute (p = 0.037) and HUI3 Emotion (p = 0.021) scores. CONCLUSION: The HUI is suitable to detect differences between normal-hearing controls and CI users, but might underestimate HRQoL changes after CI in CI users over 55.

Audiological practice and COVID-19: recommendations that audiological centers can use to maintain the safety and quality of service-expert opinion.

PURPOSE: Audiology is an essential service for some patient groups and some interventions. This article sets forth experience-based recommendations for how audiological centers can continue to safely and effectively function during COVID-19. METHODS: The recommendations are the result of panel discussion and are based on the clinical experience of the panelists/authors. RESULTS: The recommendations cover which patient groups and which interventions should be treated when and whether this can be performed in the clinic or remotely; how to maintain the safety of workplace via optimizing patient flow within the clinic and the sanitation of rooms and equipment; and overcoming communication challenges that COVID-19 intensifies. CONCLUSION: For essential audiological services to continue under COVID-19, safety measures must be implemented and maintained, and treatment and communication strategies must be adapted to offset communication difficulties due to personal protective equipment (PPE) and social distancing and to bolster patient confidence. In short, it is vital that staff feel safe, that patients either feel the clinic is safe enough to visit or that remote treatment may be an option, and that clinics and patients have a broad agreement on the urgency of any needed service. We hope that these recommendations help clinics effectively accomplish these goals.

Sound localization in patients with bilateral vestibulopathy.

PURPOSE: The goal of this study was to evaluate if bilaterally (partially) absent vestibular function during static sound localization testing, would have a negative impact on sound localization skills. Therefore, this study compared horizontal static sound localization skills of normal-hearing patients with bilateral vestibulopathy (BV) and healthy controls. METHODS: Thirteen normal-hearing patients with BV and thirteen age-matched healthy controls were included. Sound localization skills were tested using seven loudspeakers in a frontal semicircle, ranging from - 90° to + 90°. Sound location accuracy was analyzed using the root-mean-square error (RMSE) and the mean absolute error (MAE). To evaluate the severity of the BV symptoms, the following questionnaires were used: Dizziness Handicap Inventory (DHI), Oscillopsia severity questionnaire (OSQ), 12-item Spatial, Speech, and Qualities Questionnaire (SSQ12), and Health Utilities Index Mark 3 (HUI3). RESULTS: The RMSE and MAE were significantly larger (worse) in the BV group than in the healthy control group, with respective median RMSE of 4.6° and 0°, and a median MAE of 0.7° and 0°. The subjective reporting of speech perception, spatial hearing, and quality of life only demonstrated a moderate correlation between DHI (positive correlation) and HUI total score (negative correlation), and localization scores. CONCLUSION: Static sound localization skills of patients with BV were only mildly worse compared to healthy controls. However, this difference was very small and therefore most likely due to impaired cognitive function. The vestibular system does not seem to have a modulating role in sound localization during static conditions, and its impact is negligible in contrast to the impact of hearing impairment. Furthermore, the subjective reporting of speech perception, spatial hearing, and quality of life was not strongly correlated with localization scores.

Systematic Review of Quality of Life Assessments after Cochlear Implantation in Older Adults.

Cochlear implants (CI) have increasingly been adopted in older adults with severe to profound sensorineural hearing loss as a result of the growing and aging world population. Consequently, researchers have recently shown great interest in the cost-effectiveness of cochlear implantation and its effect on quality of life (QoL) in older CI users. Therefore, a systematic review and critical evaluation of the available literature on QoL in older adult CI users was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were selected by searching MEDLINE (PubMed) and the Cochrane Library and by checking the reference lists of relevant articles. Inclusion criteria were as follows: (1) the study sample were adults aged 50 years and older with postlingual onset of bilateral severe to profound hearing loss, (2) all subjects received a multi-electrode CI, and (3) QoL was assessed before and after implantation. Out of 1,093 records, 18 articles were accepted for review. Several studies demonstrated significant positive effects of cochlear implantation on QoL in older adults, but high-level evidence-based medicine is lacking. An improvement of QoL was generally reported when using disease-specific instruments, which are designed to detect treatment-specific changes, whereas the outcomes of generic QoL questionnaires, assessing general health states, were rather ambiguous. However, only generic questionnaires would be able to provide calculations of the cost-effectiveness of CI and comparisons across patient populations, diseases, or interventions. Hence, generic and disease-specific QoL instruments are complementary rather than contradictory. In general, older CI users' QoL was assessed using a variety of methods and instruments, which complicated comparisons between studies. There is a need for a standardized, multidimensional, and comprehensive QoL study protocol including all relevant generic and disease-specific instruments to measure and compare QoL, utility, and/or daily life performance in CI users.

Vestibular Function in Older Adults With Cognitive Impairment: A Systematic Review.

IMPORTANCE: Given the rising prevalence of patients with dementia and those at risk for it, early identification is prioritized. As vestibular dysfunction is associated with Alzheimer's disease (AD) and may contribute to its onset, vestibular assessment may yield an opportunity in early dementia screening. OBJECTIVE: This systematic review structures and compares the different raw outcome measures used to assess vestibular function while comparing older adults with preserved cognition to individuals with cognitive impairment, either suffering from mild cognitive impairment (MCI) or AD. DESIGN: Two investigators independently and systematically searched publications performing objectively measured vestibular testing in a patient population consisting of either MCI or AD, compared with a control group of older adults with preserved cognition. No limitations regarding language or publication date were applied. References of the retrieved articles were hand searched for relevant articles. RESULTS: Seven articles were included for analysis. A total of 235 older adults with impaired cognition (150 AD, 85 MCI) were compared with a control group of 481 older adults with preserved cognition. Evaluation of the peripheral vestibular function included video head impulse test (vHIT), videonystagmography (VNG), electronystagmography (ENG) including bithermal caloric irrigation and vestibular evoked myogenic potentials (VEMP). The VEMP test, assessing otolith function and the elicited vestibulocollic reflex (VCR), was able to differentiate subjects with AD and its prodromal stage from healthy controls, with p13 latency (p < 0.05) and amplitude (p < 0.05) having the most discriminating power.No correlation between cognitive decline and vestibulo-ocular reflex measurements in different frequency ranges of the semicircular canals (using vHIT, rotatory chair testing, and caloric irrigation) was found. Because of the limited number of available studies and the large heterogeneity in outcome measures, these results have to be interpreted with caution. CONCLUSIONS: Measurements of the VCR, as evoked by the VEMP test, discriminate between patients with cognitive impairment (MCI and AD) and older adults with preserved cognition, whereas measurements of the vestibulo-ocular reflex do not. More studies are needed to further elaborate on these findings.

Cognitive Improvement After Cochlear Implantation in Older Adults With Severe or Profound Hearing Impairment: A Prospective, Longitudinal, Controlled, Multicenter Study.

OBJECTIVE: To compare the cognitive evolution of older adults with severe or profound hearing impairment after cochlear implantation with that of a matched group of older adults with severe hearing impairment who do not receive a cochlear implant (CI). DESIGN: In this prospective, longitudinal, controlled, and multicenter study, 24 older CI users were included in the intervention group and 24 adults without a CI in the control group. The control group matched the intervention group in terms of gender, age, formal education, cognitive functioning, and residual hearing. Assessments were made at baseline and 14 months later. Primary outcome measurements included the change in the total score on the Repeatable Battery for the Assessment of Neuropsychological Status for Hearing impaired individuals score and on its subdomain score to assess cognitive evolution in both groups. Secondary outcome measurements included self-reported changes in sound quality (Hearing Implant Sound Quality Index), self-perceived hearing disability (Speech, Spatial, and Qualities of Hearing Scale), states of anxiety and depression (Hospital Anxiety and Depression Scale), and level of negative affectivity and social inhibition (Type D questionnaire). RESULTS: Improvements of the overall cognitive functioning (p = 0.05) and the subdomain "Attention" (p = 0.02) were observed after cochlear implantation in the intervention group; their scores were compared to the corresponding scores in the control group. Significant positive effects of cochlear implantation on sound quality and self-perceived hearing outcomes were found in the intervention group. Notably, 20% fewer traits of Type D personalities were measured in the intervention group after cochlear implantation. In the control group, traits of Type D personalities increased by 13%. CONCLUSION: Intervention with a CI improved cognitive functioning (domain Attention in particular) in older adults with severe hearing impairment compared to that of the matched controls with hearing impairment without a CI. However, older CI users did not, in terms of cognition, bridge the performance gap with adults with normal hearing after 1 year of CI use. The fact that experienced, older CI users still present subnormal cognitive functioning may highlight the need for additional cognitive rehabilitation in the long term after implantation.

Two-phase survey on the frequency of use and safety of MRI for hearing implant recipients.

PURPOSE: Magnetic resonance imaging (MRI) is often used to visualize and diagnose soft tissues. Hearing implant (HI) recipients are likely to require at least one MRI scan during their lifetime. However, the MRI scanner can interact with the implant magnet, resulting in complications for the HI recipient. This survey, which was conducted in two phases, aimed to evaluate the safety and performance of MRI scans for individuals with a HI manufactured by MED-EL (MED-EL GmbH, Innsbruck, Austria). METHODS: A survey was developed and distributed in two phases to HEARRING clinics to obtain information about the use of MRI for recipients of MED-EL devices. Phase 1 focused on how often MRI is used in diagnostic imaging of the head region of the cochlear implant (CI) recipients. Phase 2 collected safety information about MRI scans performed on HI recipients. RESULTS: 106 of the 126 MRI scans reported in this survey were performed at a field strength of 1.5 T, on HI recipients who wore the SYNCHRONY CI or SYNCHRONY ABI. The head and spine were the most frequently imaged regions. 123 of the 126 scans were performed without any complications; two HI recipients experienced discomfort/pain. One recipient required reimplantation after an MRI was performed using a scanner that had not been approved for that implant. There was only one case that required surgical removal of the implant to reduce the imaging artefact. CONCLUSION: Individuals with either a SYNCHRONY CI or SYNCHRONY ABI from MED-EL can safely undergo a 1.5 T MRI when it is performed according to the manufacturer's safety policies and procedures.

Bone Conduction Trial Device to Eliminate the Effect of Transcranial Attenuation: A Prospective Observational Study in Single-Sided Deaf Subjects.

OBJECTIVES: The contact miniTM (CM) is a nonimplantable, digital bone conduction device (BCD) consisting of 2 isolated units: an electronic housing, including the microphone, and a vibrator housing. The study investigated whether the CM can be used as an alternative test device for a BCD trial in single-sided deaf (SSD) adults with the microphone placed at the SSD ear and the vibrator at the normal-hearing (NH) ear (i.e., cross position). METHODS: Twenty SSD adults (mean age: 50 [±13.2] years) participated in a 2-week BCD trial with the CM on the headband in cross position. Prior to the trial, the subjects performed adaptive speech-in-noise tests in an unaided condition. After the trial, speech-in-noise tests were performed with the CM in cross position (CMcross) and ipsilateral position, i.e., both units at the SSD ear (CMipsi). Five different speech-in-noise configurations were used (S0N0; S0NNH; S0NSSD; S0°NNH+SSD; and SSSDNNH). Speech reception thresholds (SRT) were analyzed comparing the unaided, the CMcross condition, and the CMipsi condition. RESULTS: Friedman's test revealed no significant differences in SRTs between the CMcross, CMipsi, and the unaided condition for the S0N0, S0NNH, S0NSSD, and S0°NNH+SSD configuration. However, in the SSSDNNH configuration, a significant effect was found (p < 0.001). Wilcoxon pairwise comparisons with Bonferroni correction indicated that SRTs in the CMcross condition were significantly lower (i.e., better speech understanding) than those in the unaided (p < 0.001) and the CMipsi condition (p < 0.05). CONCLUSION: The CM may be a good alternative for patients with SSD, resulting in significantly better speech recognition when noise is presented to the NH ear and speech to the SSD ear. As the speech recognition results are better in the cross than the ipsilateral position, the CMcross might help to overcome the negative effect of transcranial attenuation during BCD trials.

Impact of Bilateral Vestibulopathy on Spatial and Nonspatial Cognition: A Systematic Review.

OBJECTIVES: Hearing loss is considered an independent risk factor for dementia. Growing evidence in animal and human studies suggest that not only hearing loss but also vestibular loss might result in cognitive deficits. The objective of this study is to evaluate the presence of spatial and nonspatial cognitive deficits in patients with bilateral vestibulopathy. As different causes of bilateral vestibulopathy are associated with hearing loss, the objective is to evaluate if these cognitive deficits are due to the vestibular loss of the patients with bilateral vestibulopathy, or to their hearing loss, or both. DESIGN: We performed a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. (1) Data sources: MEDLINE and the Cochrane Library. (2) Study selection: Cross-sectional studies investigating cognitive performances in human patients with bilateral vestibulopathy confirmed by quantitative vestibular testing. (3) Data extraction: Independent extraction of articles by three authors using predefined data fields, including patient- and control characteristics and cognitive outcomes. RESULTS: Ten studies reporting on 126 patients with bilateral vestibulopathy matched the inclusion criteria. Cognitive domains evaluated in patients with bilateral vestibulopathy included visuospatial abilities, memory, language, attention, and executive function. In only three studies, hearing performance of the included patients was briefly described. Nearly all studies demonstrated a significant impairment of spatial cognition in patients with bilateral vestibulopathy. In the few papers investigating nonspatial cognition, worse outcome was demonstrated in patients with bilateral vestibular loss performing cognitive tasks assessing attentional performance, memory, and executive function. CONCLUSIONS: Strong evidence exists that patients with bilateral vestibulopathy suffer from impaired spatial cognition. Recent studies even suggest impairment in other cognitive domains than spatial cognition. However, in all previous studies, conclusions on the link between cognitive performance and vestibular loss were drawn without taken hearing loss into consideration as a possible cause of the cognitive impairment.