Prevalence of vestibular symptoms in individuals with auditory neuropathy spectrum disorder - A retrospective study

Importance of Vestibulo-ocular Reflex Gain and Refixation Saccade Analysis in Individuals with Auditory Neuropathy Spectrum Disorder

Introduction  Auditory neuropathy spectrum disorder (ANSD) features the presence of otoacoustic emissions, poor speech identification score and absent auditory brainstem response. Objective  The present study was designed to evaluate the functioning of all six semicircular canals in individuals with ANSD and to compare it with those of normal-hearing individuals. Methods  A total of 50 individuals participated in the present study, in which Group I comprised 25 normal-hearing individuals, and Group II comprised 25 individuals with ANSD. All of the participants underwent case history, pure tone audiometry, immittance, otoacoustic emissions, auditory evoked response and video head impulse test (vHIT). Results  The independent sample t-test revealed significantly lower vestibulo-ocular reflex gain values in individuals with ANSD. A presence of 100% corrective refixation saccades was observed in the same group. The Pearson correlation test revealed no significant correlation between vestibulo-ocular reflex (VOR) gain with duration of hearing loss and pure tone thresholds for any of the three orthogonal planes. The chi-squared test revealed no association between the VOR gain values and the presence or absence of saccades in any of the semicircular canals ( p  > 0.05). Conclusion  Huge percentages of individuals with ANSD have been found to have associated vestibular dysfunction as well. Therefore, the vHIT can be used as one of the important tests of the vestibular test battery to evaluate all six semicircular canals in individuals with ANSD.

Is Asymmetric Hearing Loss a Risk Factor for Vestibular Dysfunction? Lesson From Big Data Analysis Based on the Korean National Health and Nutrition Survey

OBJECTIVE

The purpose of this study was to investigate whether asymmetric hearing loss affects vestibular function.

STUDY DESIGN

Retrospective cross-sectional study.

PATIENTS

Data from the 2010 Korean National Health and Nutrition Survey for adults aged 40 years or more were used.

INTERVENTIONS

The modified Romberg test and pure-tone audiometry were performed. Data were analyzed using a complex sample χ test of independence and complex sample logistic regression analysis.

MAIN OUTCOME MEASURES

Vestibular dysfunction and hearing thresholds.

RESULTS

The overall prevalence of vestibular dysfunction was 3.3% (95% confidence interval [CI], 2.5-4.3%). In adults more than 40 years of age, multivariate linear regression analyses showed that the odds ratio (OR) of vestibular dysfunction was 3.067 times higher than the reference for a 30-dB difference in hearing thresholds between both ears (CI, 1.481-6.351; p = 0.007) after adjusting for factors associated with vestibular dysfunction. Among these individuals, the risk of equilibrium disturbance was higher in the presence of low-frequency asymmetric hearing loss (OR, 2.148; CI, 1.216-3.793; p = 0.009); on the other hand, high-frequency asymmetry did not lead to a higher risk.

CONCLUSIONS

As low-frequency asymmetric hearing thresholds tend to coexist with vestibular dysfunction in adults, those with asymmetric hearing loss should be closely monitored.

Is tinnitus a major concern in individuals with auditory neuropathy spectrum disorder? - Questionnaire based study

Objective

Our study attempted to determine if tinnitus is a major concern in individuals with auditory neuropathy spectrum disorder (ANSD). The study also attempted to determine if pure tone average (PTA), speech identification scores (SIS), or reported duration of hearing loss could predict the tinnitus severity and functional handicap in adults with ANSD.

Methods

Tinnitus functional index (TFI) and tinnitus severity index (TSI) were administered on all the 40 participants diagnosed with ANSD.

Results

The mean TFI score was 44.3, which suggested moderate degree of tinnitus related functional impairment. The mean TSI score was found to be 33.3, which suggested moderate degree of severity in individuals with ANSD. The study also showed that tinnitus causes functional impairment that leading to sleep disturbances, emotional problems, and affecting the quality of life. There was no significant correlation (P > 0.05) between PTA, SIS, reported onset of hearing loss and scores of TFI or TSI.

Conclusion

Tinnitus in individuals with ANSD should also be given priority during assessment and provide appropriate tinnitus management.