The characteristics of vHIT gain and PR score in peripheral vestibular disorders

The Role of Asymmetry Values, Gain, and Pathological Saccades of the Video Head Impulse Test (vHIT) in Sudden Sensorineural Hearing Loss

OBJECTIVE

The purpose of this study was to evaluate the value of asymmetry values, gain, and pathological saccades of the video head impulse test (vHIT) in sudden sensorineural hearing loss (SSNHL).

STUDY DESIGN

Retrospective study.

SETTING

Tertiary referral center.

PATIENTS

A total of 226 individuals diagnosed with unilateral definite SSNHL were hospitalized. The assessment included a comprehensive evaluation of medical history, pure-tone test, acoustic impedance, positional test, video nystagmography (VNG), vHIT, vestibular evoked myogenic potentials (VEMPs) and magnetic resonance.

INTERVENTIONS

vHIT, VNG, cVEMP, oVEMP. Statistical analysis was performed with SPSS version 22.0 for Windows.

MAIN OUTCOME MEASURES

The asymmetry values, gain, and pathological saccades of the vHIT.

RESULTS

The abnormal gain of vHIT in anterior, horizontal, and posterior canal in SSNHL patients with vertigo were revealed in 20 of 112 (17.9%), 24 of 112 (21.4%), and 60 of 112 (53.6%), respectively. The vHIT pathological saccades (overt + covert) of anterior, horizontal, and posterior canal in SSNHL patients with vertigo were observed in 5 of 112 (4.6%), 52 of 112 (46.4%), and 58 of 112 (51.8%), respectively. Multivariate analysis indicated that the prognosis of patients with vertigo was correlated with vHIT gain of posterior canal, pathological saccade in horizontal canal, asymmetric ratio of horizontal canal gain, asymmetric ratio of posterior canal gain, Canal paresis (%) on caloric test and spontaneous nystagmus.

CONCLUSION

In the vHIT of patients with SSNHL with vertigo, the posterior canal is most easily affected. Reduced gain of posterior canal, pathological saccade of horizontal canal, and larger asymmetric gain of posterior canal and horizontal canal may be negative prognostic factors.

Do high-risk head trauma sports athletes have impaired vestibular function?

PURPOSE

The primary aim of this study was to examine the vestibular function of athletes involved in high-risk head trauma sports by means of complete vHIT testing of all six semicircular canals (SCCs). The secondary objective was to investigate whether the vestibular function is significantly reduced among athletes within certain high-risk sports.

METHODS

A prospective cross-sectional study of 137 adult athletes in football, handball, boxing, horseback riding, and ice hockey with a minimum of one reported sports-related head injury within the past five years. All subjects underwent screening with a complete examination of all six SCCs with vHIT and fulfillment of the dizziness handicap inventory (DHI).

RESULTS

Two subjects (1.5 %) fulfilled the criteria of having a pathological vHIT. Some degree of impairment of the vestibular function was seen when data was divided into individual sports and time since the last head injury. Likewise, no subjective dizziness was seen in the group of athletes when evaluated by total DHI scores. This score did not differ significantly between groups when subgrouped into number of head injuries or time since the last head injury. When divided into type of sport, total DHI scores differed significantly between groups. These total DHI-scores did, however, all fall within the range of the "no dizziness handicap" classification.

CONCLUSION

The results suggest that the vestibular function of athletes in high-risk head trauma sports is unaffected by the practice of a high-risk head trauma sport. Therefore, vHIT has no clinical utility in the assessment of a sports-related concussion (SRC) in athletes with no subjective feeling of dizziness.

Do measures of gain asymmetry and catch-up saccades improve video head impulse test agreement with caloric results?

Objective

To investigate the relative sensitivity and agreement of caloric testing and video head impulse test (vHIT) across four groups of vestibular disorders.

Methods

Caloric and vHIT results of 118 patients with either Ménière's disease, vestibular neuritis/labyrinthitis, vestibular migraine, or vestibular schwannoma were retrospectively analyzed. vHIT gain, gain asymmetry, and catch-up-saccades (≥100°/sec) were compared with reference limits of 91 controls.

Results

Abnormal caloric results and vHIT gain were recorded in 57.6 % and 33.1 % of patients, respectively. Consideration of all three measures increased vHIT sensitivity to 43.2 %, and concordance with caloric results improved from 66.1 % to 70.3 %. A significant interaction effect confirmed the relationship between tests depended on the diagnosis (p = 0.013). Vestibular migraine and vestibular neuritis/labyrinthitis produced similar results on both tests, usually normal and abnormal respectively. Vestibular schwannoma produced more caloric abnormalities than vHIT gain but not compared with catch-up-saccades and gain asymmetry; Ménière's disease produced more caloric abnormalities than all vHIT measures. When vHIT was normal (all measures), a 37 % canal paresis was 90 % specific for Ménière's disease.

Conclusions

Rates of vHIT catch-up-saccades and gain asymmetry can improve sensitivity and concordance with caloric testing, but this is disease-dependent.

Significance

vHIT outcome measures are complementary to the caloric test and each other.

Saccades of video head impulse test in Meniere's disease and Vestibular Migraine: What can we learn from?

Background

Saccades are often observed on video head impulse tests (vHIT) in patients with Meniere's Disease (MD) and Vestibular Migraine (VM). However, their saccadic features are not fully described.

Objective

This study aims to identify the saccades characteristics of MD and VM.

Methods

75 VM patients and 103 definite unilateral MD patients were enrolled in this study. First raw saccades were exported and analyzed. The VM patients were divided into left and right based on their ears, while the MD patients were separated into affected and unaffected subgroups based on their audiograms and symptoms.

Results

The MD patients have more saccades on the affected side (85% vs. 69%), and saccade velocity is more consistent than the contralateral side (shown by the coefficient of variation). The saccades occurrence rates on both sides are similar in VM (77% vs. 76%), as are other saccadic parameters. The MD patients have more significant inter-aural differences than the VM patients, manifested in higher velocity (p-value 0.000), earlier arriving (p-value 0.010), and more time-domain gathered (p-value 0.003) on the affected side.

Conclusions

Bilateral saccades are commonly observed in MD and VM. In contrast to MD, saccades on VM are subtle, scattered, and late-arrived. Furthermore, the MD patients showed inconsistent saccadic distribution with more velocity-uniform saccades on the affected side.

[Correlation between video head impulse test parameters and DHI score in patients with vestibular neuritis]

Objective:To explore the correlation between the parameters of video head impulse test （vHIT）and dizziness handicap inventory （DHI） score in patients with vestibular neuritis. Methods:Clinical data of 46 patients with vestibular neuritis were retrospectively analyzed. All the patients underwent DHI evaluation and vHIT examination. They were divided into mild handicap group, moderate handicap group and severe handicap group according to DHI score. The correlations between the parameters of vHIT and DHI score were compared among the three groups. The important parameters of vHIT were compared including vestibulo-ocular reflex （VOR） gain, gain asymmetry ratio （GA）, abnormal saccade dispersion （PR%）. Results:Of the 46 patients, 10 were in the mild handicap group, 21 in the moderate handicap group, and 15 in the severe handicap group. ①In the comparison of the mean value of lateral semicircular canal VOR gain, the vHIT gain of patients with mild, moderate and severe handicap were 0.64±0.06, 0.53±0.11 and 0.37±0.10, respectively, the mean value of VOR gain was negatively correlated with DHI score among the three groups（r=-0.545, P<0.001）, and the pairwise comparisons among the three groups was statistically significant（P<0.05）. In comparison of the mean values of lateral semicircular canal GA, the GA values of mild, moderate and severe handicap groups were 46.40±21.81, 47.59±15.17 and 56.57±17.39, respectively, there was no significant linear correlation between GA values and DHI scores among the three groups（r=0.246, P>0.05）, there was no significant difference between the three groups（P>0.05）. In comparison of the mean PR% of the lateral semicircular canal, the mean PR% of patients with mild, moderate and severe handicap group were 32.00±10.62, 53.82±17.09 and 76.00±10.01, respectively, PR% was positively correlated with DHI score（r=0.726, P<0.001）, and the comparison among the three groups was statistically significant（P<0.05）. ②The vertical semicircular canal vHIT gain of patients with mild, moderate and severe handicap was 0.63±0.06, 0.52±0.15 and 0.38±0.16, respectively, the mean of VOR gain was negatively correlated with DHI score among the three groups（r=-0.487, P<0.01）, the comparison of mild-severe and moderate-severe group was statistically significant（P<0.05）, while there was no significant difference between the mild and moderate group（P>0.05）. In the comparison of the mean values of vertical semicircular canal GA, the GA values of mild, moderate and severe handicap groups were 40.40±15.31, 46.10±19.59 and 47.87±18.05, respectively, there was no significant linear correlation between GA values and DHI scores among the three groups（r=0.047, P>0.05）, there was no significant difference in GA among the three groups（P>0.05）. The PR% of patients with mild, moderate and severe handicap were 42.40±15.39, 54.14±17.60 and 64.93±10.95, respectively, there was a positive significant correlation between PR% and DHI score（r=0.454, P<0.05）, there was statistically significant in the comparison of mild-severe group（P<0.05）, while there was no statistical significance between the other groups（P>0.05）. Conclusion:The VOR gain and PR% value of vHIT in patients with vestibular neuritis are closely related to the DHI score, which can evaluate the vestibular function and the degree of vertigo.

Synchronized refixation saccades in enhanced VVOR test. A new application for PR score

OBJECTIVE

Main objectives for this study were to develop a quantification method to obtain a Perez-Rey (PR) score adapted to the VVOR test and to evaluate the correlation of the PR score obtained with quantified VVOR with the PR score of the vHIT test.

METHODS

A new PR score calculation method for quantified VVOR test was developed using the MATLAB computational software based on saccadic response time latency variability between each head oscillation cycle of the VVOR test. Retrospective correlation between PR scores in VVOR and vHIT tests, performed in the same vHIT testing session for patients with vestibular neuritis and vestibular neurectomy, was performed to correlate new PR (VVOR) score with the classic PR (vHIT) score.

RESULTS

Thirty patients were included: 11 post-neurectomy and 19 subacute vestibular neuritis. Pearson's correlation coefficient (R2) for the overall sample was 0.92 (p < 0.001) and 95% confidence interval was 0.85 -0.96. In the linear mixed-effects statistical model developed, only PRVHIT and PRVVOR scores showed statistical association in Wald X2 test (p = 0.008).

CONCLUSION

The new developed PR score for synchronization measurement of saccadic responses in VVOR testing is a valid method that outputs synchronization values and highly correlates with PR score in vHIT test.

Group Vestibular Rehabilitation Program: A Cost-Effective Outpatient Management Option for Dizzy Patients

OBJECTIVES

This study was performed to evaluate the effectiveness of our novel group vestibular rehabilitation therapy (G-VRT) and to analyze the factors affecting outcomes.

STUDY DESIGN

Retrospective case series.

SETTING

Tertiary referral center.

PATIENTS

Patients with chronic dizziness who received G-VRT between December 2019 and July 2020.

INTERVENTION

The G-VRT program consisted of a 1-hour physical therapy session by an otologist in a small group setting.

MAIN OUTCOME MEASURES

Dizziness Handicap Inventory, visual analog scale, functional level scales, and video head impulse test, as well as the compliance to the program, were evaluated.

RESULTS

All scores of dizziness questionnaires were significantly improved after G-VRT ( p < 0.001). The overall vestibule-ocular reflex gain calculated by video head impulse test increased compared to the initial scores, whereas the average PR scores of all three semicircular canals significantly decreased from the initial scores, indicating enhanced vestibular compensation ( p < 0.05). Enrolled patients showed high compliance to the program.

CONCLUSION

G-VRT program is a cost-effective and efficient way to provide relief for chronic dizzy patients. Further case-control studies in a larger group, as well as comparative studies with generic or customized vestibular exercise, will be needed to validate the clinical value of G-VRT.

The Relationship between Meniere's Disease and Acute Low-Tone Sensorineural Hearing Loss

Objective

To analyse the vestibular function characteristics of patients with Meniere's disease and acute hypophonic sensorineural hearing loss in order to find more reliable and objective ancillary tests that will reduce misdiagnosis and missed diagnoses.

Methods

From January 2021 to December 2021, 60 healthy adults who underwent physical examination in our hospital were included in the control group, 60 patients with Meniere's disease were included in Study Group A, and 60 patients with acute low-tone sensorineural hearing loss were recruited in Study Group B. All participants underwent the caloric test (CT), video-head impulse test (vHIT), headshaking test (HST), and vestibular-evoked myogenic potential (VEMP) testing, which includes ocular vestibular-evoked myogenic potential (oVEMP) and cervical vestibular-evoked myogenic potential (cVEMP).

Results

Statistical analyses of unilateral weakness and directional preponderance (DP) in the two groups of patients found no significant differences between the two groups (P > 0.05). There was no statistically significant difference in the abnormal rate of vHIT and HST results between the two study groups (P > 0.05). There was no significant difference in the wave latencies, interwave intervals, and amplitudes of cVEMP and oVEMP, among the three groups (P > 0.05).

Conclusion

This study found that factors affecting CT, vHIT, HST, and VEMP results included age, head posture and position during testing, stimulus type, manipulation method, and control of muscle tone, and also those that are related to the testing instrument, statistical software, and manipulation procedures, resulting in different excitation rates and testing parameters. The small sample size prevented a comprehensive assessment of the differences in vestibular function between patients with Meniere's disease and acute hypotonic sensorineural hearing loss, and a larger sample size will be investigated in the future to provide useful insight into the diagnosis, treatment and differentiation of Meniere's disease, and acute hypotonic sensorineural hearing loss.

Analysis of video head impulse test saccades data in patients with vestibular migraine or probable vestibular migraine

Objective

Saccades accompanied by normal gain in video head impulse tests (vHIT) are often observed in patients with vestibular migraine (VM). However, they are not considered as an independent indicator, reducing their utility in diagnosing VM. To better understand clinical features of VM, it is necessary to understand raw saccades data.

Methods

Fourteen patients with confirmed VM, 45 patients with probable VM (p-VM) and 14 age-matched healthy volunteers were included in this study. Clinical findings related to spontaneous nystagmus (SN), positional nystagmus (PN), head-shaking nystagmus (HSN), caloric test and vHIT were recorded. Raw saccades data were exported and numbered by their sequences, and their features analyzed.

Results

VM patients showed no SN, PN or HSN, and less than half of them showed unilateral weakness (UW) on caloric test. The first saccades from lateral semicircular canal stimulation were the most predominant for both left and right sides. Neither velocity nor time parameters were significantly different when compared between the two sides. Most VM patients (86%) exhibited small saccades, around 35% of the head peak velocity, with a latency of 200–400 ms. Characteristics of saccades were similar in patients with p-VM. Only four normal subjects showed saccades, all unilateral and seemingly random.

Conclusions

Small saccades involving bilateral semicircular canals with a scattered distribution pattern are common in patients with VM and p-VM.

Machine learning method intervention: Determine proper screening tests for vestibular disorders

OBJECTIVE

To evaluate the performance of different vestibular indicators in disease classification based on machine learning method.

METHODS

This study use retrospective analysis of the vertigo outpatient database from a tertiary care general hospital. 1491 patients with definite clinical diagnoses were enrolled in this study. Spontaneous nystagmus, head-shaking nystagmus, positional nystagmus, unilateral weakness in caloric test, and gain and saccade in video head impulse test (vHIT) were recorded as variables. Diagnoses were mainly reorganized as acute vestibular syndrome, episodic vestibular syndrome, and chronic vestibular syndrome. The trained random forest model was applied based on exploratory data analysis results.

RESULTS

Random forest accuracies on acute, episodic, and chronic vestibular syndrome are 90%, 81.74%, and 91.3%, respectively. The most important features in acute vestibular syndrome are spontaneous nystagmus, and vHIT variables. In episodic vestibular syndrome, unilateral weakness in caloric test, gain and saccades on lateral semicircular canal are the top three parameters. Lateral vHIT gain, head-shaking nystagmus, and unilateral weakness in caloric test are the main parameters on chronic vestibular syndrome. In acute vestibular syndrome, spontaneous nystagmus and vHIT make major contributions in vestibular disorders distinction. When the disease course prolongation, unilateral weakness and head-shaking nystagmus become increasingly important.

CONCLUSION

Fast clinical test sets including spontaneous nystagmus, head shaking nystagmus, and vHIT should be the first consideration in screening vestibular disorders.

Exploratory saccades data analysis of video head impulse test in Different Meniere's Disease Stages

BACKGROUND

Unapparent saccades in video head impulse test (vHIT) are usually present in MD patients but tend to be ignored by the clinician. The result of vHIT is constantly questioned in MD patients due to a lack of uniform metrics. A more effective indicator is needed for indicating MD's pathological progress.

OBJECTIVES

To get a comprehensive understanding of the nature and usability of saccades in different MD stages.

METHODS

118 patients diagnosed with unilateral MD were recruited in this study. Patient history, audiological examination, caloric test, vHIT were performed. We proposed 'raw saccades' to represent all showed wave peaks behind the head peak and named saccades by their appearance sequence: 1st saccade, 2nd saccade and 3rd saccade. An exploratory saccade analysis was executed to investigate the effectiveness of saccade attributes in identifying MD stages.

RESULTS

MD patients have greater detectable 1st saccade than PR score as well as 2nd saccade. The time and velocity of the 1st saccade show high interaural variability (p = 0.028, p = 0.000 respectively). No statistical difference concerning the vHIT gain, PR score and 2nd saccade among stages could be recognized on both affected and contralateral sides. Multiple comparisons show the affected 1st saccade velocity and affected 1st saccade absolute velocity have stage-difference. At late stages (3&4), the affected 1st saccade is manifested as a speed increase, and this measure shows a relatively high correlation with MD stages compared to other vestibular indicators.

CONCLUSION

The 1st saccade velocity on the affected side could indicate the MD disease process and severity.