Clinical Balance Testing to Screen for Patients With Vestibular Disorders: A Retrospective Case-control Study

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.

The reliability of the Dutch version of the vestibular activities avoidance instrument in persons with and without dizziness

BACKGROUND

Avoidance of activities that trigger dizziness in persons with vestibular disorders may inhibit dynamic vestibular compensation mechanisms.

OBJECTIVE

To determine the reliability of the Vestibular Activities Avoidance Instrument (VAAI) 81 and 9 item tool and to compare the VAAI scores in Dutch-speaking healthy adults and in patients with vestibular disorders.

METHODS

A prospective cohort study was conducted including 151 healthy participants and 106 participants with dizziness. All participants completed the 81-item VAAI. Within 7 days, the VAAI was completed a second time by 102 healthy adults and 43 persons with dizziness.

RESULTS

The average 81-item VAAI scores [54.8(47.1) vs. 228.1(78.3)] and 9-item VAAI scores [2.4(5.9) vs. 28.1(12)] were significantly different between healthy adults and participants with dizziness (p < 0.001). In participants with dizziness the ICC for the 81-item VAAI was 0.95 (95% CI: 0.91, 0.97) and for the 9-item VAAI was 0.92 (95% CI: 0.85, 0.95). Cronbach's alpha for the 81-item VAAI was 0.97 and 0.85 for the 9-item VAAI. The minimal detectable change was 47.8 for the 81-item VAAI and 8.9 for the 9-item VAAI.

CONCLUSIONS

Persons with dizziness have a greater tendency to avoid movements. Both test-retest reliability and internal consistency of the Dutch version of the VAAI were excellent.

Subjective perception of activity level: A prognostic factor for developing chronic dizziness after vestibular schwannoma resection?

Introduction

A vestibular schwannoma (VS) resection causes an acute unilateral vestibular deafferentation resulting in acute postoperative symptoms. Despite the expected resolution of most of the symptoms, due to central vestibular compensation, more than one out of four patients develop chronic dizziness. Several predictive factors, such as age and tumor size, have been suggested. Despite its potential effect on the process of central vestibular compensation, the level of physical activity after VS resection was not yet considered. Therefore, the association between the level of physical activity and chronic dizziness after VS resection will be investigated.

Methods

This retrospective cohort study included 66 patients who underwent a retro-sigmoid VS resection between October 2001 and February 2007. Patients were assessed before surgery and at 9 weeks and 6 months postoperatively. At 9 weeks, patients were asked to report their level of physical activity (PA) during the past week by using a visual analogue scale and their balance performance was assessed by four standing balance conditions with eyes closed and the Timed Up and Go test (TUG). Based on the Dizziness Handicap Inventory (DHI) score at 6 months, patients were divided in a chronic dizziness group (DHI > 30) and non-chronic dizziness group (DHI-score ≤ 30). Age, sex, Koos classification, preoperative vestibular function, treatment group, balance performance, and level of PA were compared between both groups and used as independent variables in linear regression analyses with the DHI score at 6 months as dependent variable.

Results

The chronic dizzy patients revealed to have significantly lower levels of PA (p < 0.001) and worse static and dynamic balance performance (p = 0.023 and p = 0.041, respectively) 9 weeks after surgery. After elimination, the multiple regression analysis resulted in a model with two variables (PA level, TUG) which significantly predicted the DHI score (F_2,42 = 6.581; R² = 0.239; p = 0.003).

Conclusion

This study revealed associations between (1) the level of PA and balance performance in the subacute phase and (2) chronic dizziness after VS resection. Assessment of the level of PA and balance performance during the subacute phase, which can be performed in a non-invasive and non-time-consuming way, might therefore provide prognostic information after VS resection.