Clinical significance of video head impulse test in benign paroxysmal positional vertigo: a meta-analysis

Vestibular function in cases of posterior semicircular canal canalolithiasis and cupulolithiasis

Objective

To analyze and compare the vestibular function of posterior canal cupulolithiasis and canalolithiasis.

Methods

The results of posterior cupulolithiasis in 45 cases, posterior canalolithiasis in 122 cases and 19 healthy controls were analyzed retrospectively.

Results

The abnormal rates of vHIT in the canalolithiasis group and the cupulolithiasis group were 42.6 and 37.8%, respectively, both higher than those in the control group (both p < 0.05); there was no statistically significant difference between two BPPV groups (p = 0.573). The abnormal vHIT in 76.9% of the canalolithiasis cases and 82.4% of the cupulolithiasis cases showed normal gain with saccades, with no difference between the groups (p = 0.859). The lesion location of vHIT in the two groups did not show a correlation with the affected side of BPPV (both p > 0.05). 84.4% of canalolithiasis and 65.0% of cupulolithiasis had abnormal VEMP results, with no significant differences in abnormality rates or sides (both p > 0.05). Abnormal results of VEMPs did not show any correlation with side (p > 0.05). The results of pc-ca and pc-cu were both abnormal in 14 cases and 7 cases, and there was no correlation between the site and side of the injury (all p > 0.05).

Conclusion

The results of vHIT and VEMP in pc-cu and pc-ca were partially abnormal, but they did not show any correlation with side of BPPV. It can be considered that there are scattered vestibular peripheral organ damage in both groups.

A Paradoxical Clinical Coincidence: Benign Paroxysmal Positional Vertigo and Bilateral Vestibulopathy

Benign paroxysmal positional vertigo (BPPV) and bilateral vestibulopathy (BVL) are two completely different forms of vestibular disorder that occasionally occur in the same patient. We conducted a retrospective review searching for that coincidence in our database of the patients seen over a 15-year period and found this disorder in 23 patients, that is 0.4%. More frequently they occurred sequentially (10/23) and BPPV was diagnosed first. Simultaneous presentation occurred in 9/23 patients. It was subsequently studied, but in a prospective manner, in patients with BPPV on all of whom a video head impulse test was performed to search for bilateral vestibular loss; we found it was slightly more frequent (6/405). Both disorders were treated accordingly, and it was found that the results follow the general trend in patients with only one of those disorders.

Spontaneous Nystagmus in Patients With Posterior Semicircular Canal Benign Paroxysmal Positional Vertigo

OBJECTIVE

This study aimed to investigate the incidence of spontaneous nystagmus (SN) in posterior semicircular canal (PSCC) benign paroxysmal positional vertigo (BPPV) and its effect on treatment outcomes.

STUDY DESIGN

Retrospective case series.

SETTING

Tertiary referral center.

METHODS

This study included 50 patients with idiopathic unilateral PSCC BPPV between July 2021 and May 2022. The presence of SN was investigated, and the results of the bithermal caloric test and video head impulse test (vHIT) were compared.

RESULTS

SN was observed in 13 (26%) of the 50 patients presenting PSCC BPPV. The direction of SN was mainly unidirectional and horizontal in 12 of the 13 patients with a slow-phase velocity ranging from 2 to 4°/s. One patient presented an upbeating torsional SN at the initial evaluation. The mean vHIT gain of the PSCC on the affected side was significantly lower in patients with SN than those without SN (p = .004, Mann-Whitney U test). The proportion of patients who recovered within 2 sessions of the repositioning maneuver was significantly higher in those without SN than that in those with SN (p < .001, Fisher's exact test).

CONCLUSION

This study demonstrated that the treatment outcomes of PSCC BPPV were significantly worse in patients with SN than those without SN. Examining the presence of SN in patients with PSCC BPPV may be helpful in counseling the patients on prognosis, and it is expected that more sessions of canalith repositioning maneuver may be required to treat PSCC BPPV in patients with SN than those without SN.

Assessment of semicircular canal function in benign paroxysmal positional vertigo using the video head impulse test and caloric test

Objective

To assess semicircular canal function in benign paroxysmal positional vertigo (BPPV) using the video head impulse test (vHIT) and caloric test.

Methods

We retrospectively reviewed 39 patients with idiopathic BPPV who underwent both vHIT and the caloric test. Twenty-one patients had posterior BPPV (p-BPPV) and eighteen had horizontal BPPV (h-BPPV). Vestibulo-ocular reflex (VOR) gain and corrective saccades (CS) were analyzed in vHIT and canal paresis (CP) was calculated in the caloric test.

Results

The mean VOR gain of the posterior canal in p-BPPV was 0.75 ± 0.28 on the affected side, which was significantly smaller than that on the contralateral side (0.93 ± 0.24, p = .00738). On the other hand, there were no significant differences in the VOR gain of the horizontal canal in h-BPPV between the affected and the contralateral sides (p = .769). The rates of the presence of CS were not significantly different between the affected canal and the contralateral canal either in p-BPPV (p = .111) or h-BPPV (p = .0599). The mean CP value in h-BPPV patients (43.5 ± 31.3%) was significantly higher than that in p-BPPV patients (22.2 ± 22.9%; p = .0184).

Conclusion

The VOR gain of vHIT in the affected canal was significantly smaller than that in the contralateral canal in p-BPPV, but not in h-BPPV. The caloric responses of the affected canal are reduced to a significantly larger extent in h-BPPV compared to p-BPPV. These results suggest that BPPV affects the semicircular canal function differently depending on which semicircular canal is involved.

Correlation between nystagmus intensity and vestibular-ocular reflex gain in benign paroxysmal positional vertigo: A prospective, clinical study

BACKGROUND

Video head impulse test (vHIT) and videonystagmography (VNG) provide significant benefits in evaluating benign paroxysmal positional vertigo (BPPV) and determining the semicircular canal localization of the otoconia.

OBJECTIVE

This study aimed to investigate the relationship between vestibular-ocular reflex (VOR) gains measured via vHIT and the slow-phase velocity (SPV) of nystagmus in patients with the posterior semicircular canal (PSCC)-BPPV.

METHODS

Sixty-two patients were included in this study and divided into the study (n = 32, patients with isolated PSCC-BPPV) and control (n = 30, age- and sex-matched healthy individuals) groups. While VOR gains were measured with vHIT in both groups and compared between groups, the SPV values of nystagmus observed during the Dix-Hallpike maneuver in the study group were recorded using VNG and compared with the VOR gains of the study group.

RESULTS

There were significant differences in posterior canal VOR gains between the study and control groups (p < 0.001 and p < 0.01, respectively). Although the affected PSCC had decreased VOR gains versus the control group, it was still within the normal range. However, there was no significant relationship between the VOR gains of the affected PSCC and the SPV of the nystagmus.

CONCLUSIONS

vHIT can help detect semicircular canal dysfunction in patients with PSCC-BPPV. The SPV values of nystagmus on VNG during the Dix-Hallpike maneuver do not correlate with the level of VOR gain.

Video Head Impulse Test Findings in Patients With Benign Paroxysmal Positional Vertigo Secondary to Idiopathic Sudden Sensorineural Hearing Loss

Benign paroxysmal positional vertigo (BPPV) is amongst the most common causes of episodic vestibular syndrome. It can be classified as idiopathic and secondary types according to the causative factors, and the underlying mechanism between idiopathic (i-BPPV) and secondary BPPV (s-BPPV) may differ. Idiopathic sudden sensorineural hearing loss (ISSNHL) has been considered as a common inner ear disease that precipitates s-BPPV. Yet, few studies have addressed the functional impairment of the semicircular canal (SCC) system in patients with s-BPPV associated with ISSNHL. Our purpose was to explore the pathophysiological mechanism and investigate the clinical implications of video head impulse test (vHIT) in these patients. Here, the clinical and laboratory data of patients with BPPV secondary to ISSNHL, including the results of vHIT, were retrospectively reviewed, and compared with those of patients with i-BPPV. Pathological vHIT findings (low vestibulo-ocular reflex gain and re-fixation saccade), which mainly affected the posterior SCC, were more common in the s-BPPV group than in the i-BPPV group (41.9 and 0%, respectively). The incidence of horizontal SCC involvement was also higher in the s-BPPV group (45.16 and 16.67%, respectively). Furthermore, patients with s-BPPV showed lower vHIT gains of the posterior and horizontal SCCs in affected ears than in unaffected ears. Compared to i-BPPV, posterior SCC paresis detected by vHIT is more prevalent in BPPV secondary to ISSNHL. This dysfunction may be associated mainly with vestibular impairments caused by ISSNHL, and not with BPPV per se.

Vestibular function testing in the 21st century: video head impulse test, vestibular evoked myogenic potential, video nystagmography; which tests will provide answers?

PURPOSE OF REVIEW

To most neurologists, assessing the patient with vertigo is an unpleasant and worrisome task. A structured history and focused examination can be complemented by carefully selected laboratory tests, to reach an early and accurate diagnosis. We provide evidence-based recommendations for vestibular test selection.

RECENT FINDINGS

The video head impulse test (vHIT), cervical and ocular vestibular evoked myogenic potential (VEMP) and home-video nystagmography are four modern, noninvasive methods of assessing vestibular function, which are equally applicable in the hospital and office-practice. Collectively, they enable assessment of all five vestibular end-organs. The prevalence and patterns of test abnormalities are distinct for each vestibular disorder. We summarize typical abnormalities encountered in four common vestibular syndromes.

SUMMARY

In the context of acute vestibular syndrome, an abnormal vHIT with low gain and large amplitude refixation saccades and an asymmetric oVEMP separates innocuous vestibular neuritis from stroke. In episodic spontaneous vertigo, high-velocity ictal nystagmus and asymmetric cVEMP help separate Ménière's disease from vestibular migraine. In chronic imbalance, all three tests help detect unilateral or bilateral vestibular loss as the root cause. Recurrent positional vertigo requires no laboratory test and can be diagnosed and treated at the bedside, guided by video nystagmography.