VOR gain of lateral semicircular canal using video head impulse test in acute unilateral vestibular hypofunction: A systematic review

Vestibulo-Ocular Reflex Function and Its Impact on Postural Stability and Quality of Life in Cochlear Implant Recipients: A Cross-Sectional Study

BACKGROUND/OBJECTIVES

Vestibulo-ocular reflex (VOR) function, measured by the video head impulse test (vHIT) gains, plays a crucial role in postural stability and quality of life. Cochlear implant recipients often experience vestibular dysfunction, but its relationship with balance and patient-reported outcomes remains underexplored. This study aimed to (1) evaluate the relationship between vHIT gains and postural stability in cochlear implant recipients; (2) assess the impact of vHIT gains on quality-of-life metrics; and (3) identify key predictors of postural stability, including vHIT gains and demographic/clinical characteristics.

METHODS

This cross-sectional study was conducted between August 2023 and February 2024 and included 46 participants that comprised cochlear implant recipients and age-matched normal hearers who underwent the vHIT for lateral, anterior, and posterior semicircular canal function. Postural stability was assessed using dynamic posturography, and quality of life was measured using the Short Form-36 (SF-36). Multiple linear regression and correlation analyses were performed.

RESULTS

The vHIT gains demonstrated significant positive correlations with postural stability, with the lateral canal showing the strongest association (r = 0.742, p = 0.001), followed by the posterior (r = 0.701, p = 0.003) and anterior canals (r = 0.684, p = 0.005). A multiple regression analysis identified the lateral canal as the most significant predictor of postural stability (β = 0.512, p = 0.001, adjusted R2 = 0.47). Quality-of-life metrics were inversely correlated with the vHIT gains, particularly in the posterior canal (r = -0.712, p = 0.002), which explained 43-51% of the variance.

CONCLUSIONS

This study highlighted the lateral semicircular canal as the primary determinant of postural stability in cochlear implant recipients, underscoring the importance of vestibular assessments in optimizing balance and functional outcomes.

Video head impulse test in subacute and chronic stroke survivors: new perspectives for implementation of assessment in rehabilitation

INTRODUCTION

The Video Head Impulse Test (vHIT) is a safe and reliable assessment of peripheral vestibular function. Many studies tested its accuracy in clinical settings for differential diagnosis and quantification of the vestibulo-oculomotor reflex (VOR) in various disorders. However, the results of its application after lesions of the CNS are discordant and have never been studied in rehabilitation. This study aims to assess the VOR performance in a sample of stroke survivors.

METHODS

This is a cross-sectional study on 36 subacute and chronic stroke survivors; only persons with first-ever stroke and able to walk independently, even with supervision, were included. We performed VOR assessments for each semicircular canal by vHIT and balance assessments by the Berg Balance Scale and the MiniBESTest scale.

RESULTS

Two hundred and sixteen semicircular canals were assessed using the Head Impulse paradigm (in both the vertical and horizontal planes), while 72 semicircular canals were assessed using the Suppressed Head Impulse paradigm (horizontal plane). There was a high prevalence of participants with dysfunctional canals, particularly for the left anterior and right posterior canals, which were each prevalent in more than one-third of our sample. Furthermore, 16 persons showed an isolated canal dysfunction. The mean VOR gain for the vertical canals had confidence intervals out of the normal values (0.74-0.91 right anterior; 0.74-0.82 right posterior; 0.73-0.87 left anterior).

CONCLUSION

Our findings suggest that peripheral vestibular function may be impaired in people with stroke; a systematic assessment in a rehabilitation setting could allow a more personalized and patient-centred approach.

Compensatory strategies after an acute unilateral vestibulopathy: a prospective observational study

PURPOSE

In case of an acute unilateral vestibulopathy (UVP), compensatory strategies such as restoration and adaptation will lead to a decrease in intensity of the symptoms. Although measurements of compensatory strategies are available, currently, an overview taking the different strategies into account is lacking. The objectives of this study are to explore compensatory strategies and to investigate the association between compensatory strategies and patient characteristics.

METHODS

Restoration was objectified by the vestibulo-ocular reflex (VOR) gain on the video head impulse test, and adaptation-consisting of visual, multisensory, and behavioral substitution-was objectified by the Visual Vertigo Analog Scale (VVAS), Antwerp Vestibular Compensation Index (AVeCI), and Perez and Rey score (PR score), respectively. Adequate restoration and adaptation levels were interpreted as follows: VOR gain > 0.80, VVAS ≤ 40%, AVeCI > 0 and PR score ≤ 55.

RESULTS

Sixty-two UVP patients, 34 men and 28 women, were included with an average age of 52.1 ± 17.3 years. At 10.5 ± 1.4 weeks after onset, 41.9% of the UVP patients reached adequate restoration levels and 58.1-86.9% reached adequate adaptation levels. Furthermore, significant associations were found between (1) restoration status and UVP etiology [Odds Ratio (OR) with 95% CI: 4.167 {1.353;12.828}] and balance performance (OR: 4.400 {1.258;15.386}), (2) visual sensory substitution status and perceived handicap (OR: 8.144 {1.644;40.395}), anxiety (OR: 10.000 {1.579;63.316}) and depression (OR: 16.667 {2.726;101.896}), and (3) behavioral substitution status and balance performance (OR: 4.143 {1.341;12.798}).

CONCLUSION

UVP patients with adequate compensatory strategies presented with better balance performance, lower perceived handicap, and lower anxiety and depression scores.

Comparative utility of vestibular function tests in patients with peripheral and central vestibular dysfunction

Background

Bithermal caloric irrigation, video head impulse test (vHIT), and rotational testing are commonly used to assess peripheral vestibular function, but the relative clinical utility of each test in differentiating patients with peripheral vestibulopathy is debated.

Objectives

To determine whether (1) the combination of two or more vestibular tests enhances diagnostic utility over a single test; (2) abnormal test results on vestibular tests correlate with one another.

Methods

Retrospective analysis of data collected from multidisciplinary vestibular clinics at two academic medical centers from 2016 to 2022.

Results

150 patients (54.10 ± 15.09 years, 88 females) were included. No individual test was significantly better at predicting the presence of peripheral vestibular damage (p > 0.05). vHIT test results improved significantly when combined with either the caloric test (p = 0.007) or rotary chair test (p = 0.039). Caloric and rotational testing had high sensitivity (74.65% and 76.06%, respectively) and specificity (83.54% and 78.48%, respectively). vHIT demonstrated excellent specificity (89.87%) but poor sensitivity (47.89%). Caloric, vHIT, and rotary chair tests results did not correlate with one another (p > 0.05).

Conclusions

Vestibular function tests have comparable diagnostic utility, yet each offers unique advantages. Caloric and rotational testing may be best suited for screening peripheral damage and vHIT may function ideally as a confirmatory test.