Normal Vestibulo Ocular Reflex (VOR) gain Measured Using the Video Head Impulse Test (vHIT) in Healthy Young Adults

Introduction: Many new objective tests to assess the function of specific structures of the vestibular organ are currently adopted in vestibular clinics. One of the objective assessments include the video head impulse test (vHIT) where gain & velocity responses of eye relative to the head movements are recorded using an infrared camera. Methods: Thirty normal hearing subjects age between 18 to 25 years old participated in this study. At least ten Lateral, Left Anterior Right Posterior (LARP), and Right Anterior Left Posterior (RALP) responses were recorded for each participant by making small and rapid unpredictable head movements. Results: The average velocity gain for Lateral responses at 40 ms, 60 ms and 80 ms were 1.05 ± 0.003, 1.03 ± 0.002 and 1.01 ± 0.003 respectively. The LARP average velocity regression were 1.01 ± 0.24 for Left Anterior and 1.05 ± 0.25 for Right Posterior, with an average gain asymmetry of 5.13%. The RALP average velocity regression were 1.08 ± 0.31 for Right Anterior and 1.12 ± 0.30 for Left Posterior, with an average gain asymmetry of 5.87%. One sample T-test were conducted to compare Lateral responses to a previous study by Mossman et al. (2015) where significant differences in velocity gain at 60 ms and 80 ms between studies were found where, t (59) = 5.56, p <0.01 and t (59) = 2.86, p >< 0.01 respectively. Conclusion: This indicates the importance of establishing on-site norms for every clinical settings as techniques used and equipment differences could affect the results.

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Normal Saccadic Responses Using Video Head Impulse Test In Healthy Young Adults

IIUM Medical Journal Malaysia ◽

10.31436/imjm.v17i1.873 ◽

2018 ◽

Vol 17 (1) ◽

Author(s):

Nurul Amira Omar ◽

Saiful Adli bin Jamaluddin

Keyword(s):

Average Velocity ◽

Infrared Camera ◽

Head Movements ◽

Head Impulse Test ◽

Video Head Impulse Test ◽

Head Impulse ◽

Velocity Gain ◽

Left Posterior ◽

History Of

Introduction: Vertigo and dizziness are common symptoms reported in audiology and ENT clinics. One of the objective assessments includes the video head impulse test (vHIT) where gain & amp; velocity responses of eye movements relative to the head movements are recorded using an infrared camera. Materials and Methods: Thirty normal hearing subjects age between 18 to 25 years old participated in this study. Exclusion factors include those with the history of head or neck injury and vertigo. At least ten lateral, left anterior right posterior (LARP), and right anterior left posterior (RALP) responses were recorded for each participant by making small unpredictable head movements. Results: The average velocity gain for lateral responses at 40 ms, 60 ms and 80 ms were 1.05 ± 0.003, 1.03 ± 0.002 and 1.01 ± 0.003 respectively. The LARP and RALP average velocity regression were 1.01 ± 0.24 for left anterior and 1.05 ± 0.25 for right posterior, 1.08±0.31 for right anterior and 1.12 ± 0.30 for left posterior. One sample T-test was conducted to compare lateral responses to a previous study by Mossman et al. 2015. There were significant differences in velocity gain at 60 ms and 80 ms where, t (59) = 5.56, p < 0.01 and t (59) = 2.86, p < 0.01, respectively. Conclusion: This indicates the importance of establishing norms for clinics as various factors could affect the results such as techniques used and equipment differences. A follow-up study on subjects with vestibular disorders is required to validate this data as a normative reference.

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Viewing Target Distance Influences the Vestibulo-Ocular Reflex Gain when Assessed Using the Video Head Impulse Test

Audiology and Neurotology ◽

10.1159/000493845 ◽

2018 ◽

Vol 23 (5) ◽

pp. 285-289 ◽

Cited By ~ 2

Author(s):

Patricia Castro ◽

Sara Sena Esteves ◽

Florencia Lerchundi ◽

David Buckwell ◽

Michael A. Gresty ◽

...

Keyword(s):

Head Movements ◽

Target Distance ◽

Head Impulse Test ◽

Video Head Impulse Test ◽

Gaze Stabilization ◽

Head Impulse ◽

Ocular Reflex ◽

Significant Difference ◽

Vestibulo Ocular Reflex ◽

Reflex Gain

Gaze stabilization during head movements is provided by the vestibulo-ocular reflex (VOR). Clinical assessment of this reflex is performed using the video Head Impulse Test (vHIT). To date, the influence of different fixation distances on VOR gain using the vHIT has not been explored. We assessed the effect of target proximity on the horizontal VOR using the vHIT. Firstly, we assessed the VOR gain in 18 healthy subjects with 5 viewing target distances (150, 40, 30, 20, and 10 cm). The gain increased significantly as the viewing target distance decreased. A second experiment on 10 subjects was performed in darkness whilst the subjects were imagining targets at different distances. There were significant inverse relationships between gain and distance for both the real and the imaginary targets. There was a statistically significant difference between light and dark gains for the 20- and 40-cm distances, but not for the 150-cm distance. Theoretical VOR gains for different target distances were calculated and compared with those found in light and darkness. The increase in gain observed for near targets was lower than predicted by geometrical calculations, implying a physiological ceiling effect on the VOR. The VOR gain in the dark, as assessed with the vHIT, demonstrates an enhancement associated with a reduced target distance.

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Evaluation of Interexaminer Variability in Video Head Impulse Test Results

Journal of the American Academy of Audiology ◽

10.1055/s-0040-1717124 ◽

2020 ◽

Vol 31 (08) ◽

pp. 613-619

Author(s):

Başak Mutlu ◽

Sıdıka Cesur ◽

Merve Torun Topçu ◽

Cennet Reyyan Geçici ◽

Öyküm Esra Aşkın ◽

...

Keyword(s):

Repeated Measures ◽

Semicircular Canals ◽

Head Impulse Test ◽

Video Head Impulse Test ◽

Head Impulse ◽

Lateral Canal ◽

Ocular Reflex ◽

Left Posterior ◽

Vestibulo Ocular Reflex ◽

The Right

Abstract Objective The video head impulse test (vHIT) is a diagnostic tool to assess the function of the semicircular canals and branches of the vestibular nerve. The aim of this study was to analyze the interexaminer variability of vHIT results in healthy subjects. Materials and Methods A total of 21 healthy participants were included in the study. vHIT responses were collected by four clinicians. Variability of the vHIT results between examiners was analyzed statistically. Results The vestibulo-ocular reflex (VOR) velocity regression values were from 0.99 to 1.09 degrees per second for the lateral canals. For the vertical canals, VOR velocity regression values were from 0.87 to 1.21 degrees per second. According to repeated measures analysis of variance, the normality assumptions for the velocity regression of the left lateral canal (p = 0.002) and the right anterior canal (p < 0.01) were met and the differences were statistically significant. The normality assumptions were not met for 40, 60, and 80 ms median gain of the right lateral canal (p = 0.016, p = 0.038, and p = 0.001, respectively); 40 and 60 ms median gain of the left lateral canal (p < 0.001 and p = 0.008, respectively); and the velocity regression of the left posterior canal (p < 0.00). These differences were found to be statistically significant by using the Friedman test. Conclusion The interexaminer differences of the VOR gain values for the vHIT were statistically significant. Serial vHIT testing should be performed by the same examiner to reduce the effects of interexaminer variability.

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Vestibular semicircular canal function as detected by video Head Impulse Test (vHIT) is essentially unchanged in people with Parkinson’s disease compared to healthy controls

Journal of Vestibular Research ◽

10.3233/ves-201626 ◽

2021 ◽

pp. 1-9

Author(s):

Kim E. Hawkins ◽

Elodie Chiarovano ◽

Serene S. Paul ◽

Ann M Burgess ◽

Hamish G. MacDougall ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Semicircular Canal ◽

Neurodegenerative Disorder ◽

Vestibular Function ◽

Head Impulse Test ◽

Healthy Controls ◽

Video Head Impulse Test ◽

Head Impulse ◽

Vestibulo Ocular Reflex

BACKGROUND: Parkinson’s disease (PD) is a common multi-system neurodegenerative disorder with possible vestibular system dysfunction, but prior vestibular function test findings are equivocal. OBJECTIVE: To report and compare vestibulo-ocular reflex (VOR) gain as measured by the video head impulse test (vHIT) in participants with PD, including tremor dominant and postural instability/gait dysfunction phenotypes, with healthy controls (HC). METHODS: Forty participants with PD and 40 age- and gender-matched HC had their vestibular function assessed. Lateral and vertical semicircular canal VOR gains were measured with vHIT. VOR canal gains between PD participants and HC were compared with independent samples t-tests. Two distinct PD phenotypes were compared to HC using Tukey’s ANOVA. The relationship of VOR gain with PD duration, phenotype, severity and age were investigated using logistic regression. RESULTS: There were no significant differences between groups in vHIT VOR gain for lateral or vertical canals. There was no evidence of an effect of PD severity, phenotype or age on VOR gains in the PD group. CONCLUSION: The impulsive angular VOR pathways are not significantly affected by the pathophysiological changes associated with mild to moderate PD.

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Vestibulo-ocular reflex assessed with Video Head Impulse Test in children with Vestibular Migraine: Our experience

International Journal of Pediatric Otorhinolaryngology ◽

10.1016/j.ijporl.2020.110161 ◽

2020 ◽

Vol 137 ◽

pp. 110161

Author(s):

Rosana Rodríguez-Villalba ◽

Miguel Caballero-Borrego ◽

Vanessa Villarraga ◽

Victoria Rivero de Jesús ◽

Maria Antonia Claveria ◽

...

Keyword(s):

Vestibular Migraine ◽

Head Impulse Test ◽

Video Head Impulse Test ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex

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Vestibulo-ocular reflex gain and compensatory saccades in three semicircular canals by video head impulse test

Auditory and Vestibular Research ◽

10.18502/avr.v28i1.415 ◽

2019 ◽

Author(s):

Homa Zarrinkoob ◽

Hadi Behzad ◽

Seyed Mehdi Tabatabaee

Keyword(s):

High Velocity ◽

Semicircular Canals ◽

Head Impulse Test ◽

Video Head Impulse Test ◽

Low Velocity ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain ◽

The Right

Background and Aim: One of the tools for assessing the vestibulo-ocular reflex (VOR) is using video head impulse test (vHIT). In this test by placing the head at different angles and shaking the head, three semicircular canals of the vestibular system in each ear can be examined separately. The purpose of this study was to investigate the relationship between the low and high velocities of the vHIT test with VOR and its compensatory saccades. Methods: The vHIT test was performed by an examiner in 49 normal individuals aged 23–39 at low and high velocities. All participants had normal hearing, visual, and vestibular systems. Results: Mean gains in the horizontal, anterior and posterior semicircular canals in the right ear respectively were 0.92, 1 and 0.90 and in the left ear 0.93, 0.99 and 0.95 for low velocity and 0.78, 0.92 and 0.79 in the right ear and 0.80, 0.85 and 0.86 in the left ear for high velocity. Also, the number of compensatory saccade at high velocity was higher than those at the low velocity and the latency of compensatory saccade was lower at the higher velocity. Conclusion: In the vHIT test, VOR gain decreases at high velocity that is statistically significant. Also, compensatory saccades are more likely to occur at high velocity with smaller delay. Therefore, high-velocity vHIT test is not recommended for the purpose of examining the VOR gain and compensatory saccade.

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The Effect of Different Head Movement Paradigms on Vestibulo-Ocular Reflex Gain and Saccadic Eye Responses in the Suppression Head Impulse Test in Healthy Adult Volunteers

Frontiers in Neurology ◽

10.3389/fneur.2021.729081 ◽

2021 ◽

Vol 12 ◽

Author(s):

Dmitrii Starkov ◽

Bernd Vermorken ◽

T. S. Van Dooren ◽

Lisa Van Stiphout ◽

Miranda Janssen ◽

...

Keyword(s):

Healthy Subjects ◽

Healthy Adult ◽

Head Movements ◽

Head Impulse Test ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain ◽

Head Impulses ◽

Adult Volunteers

Objective: This study aimed to identify differences in vestibulo-ocular reflex gain (VOR gain) and saccadic response in the suppression head impulse paradigm (SHIMP) between predictable and less predictable head movements, in a group of healthy subjects. It was hypothesized that higher prediction could lead to a lower VOR gain, a shorter saccadic latency, and higher grouping of saccades.Methods: Sixty-two healthy subjects were tested using the video head impulse test and SHIMPs in four conditions: active and passive head movements for both inward and outward directions. VOR gain, latency of the first saccade, and the level of saccade grouping (PR-score) were compared among conditions. Inward and active head movements were considered to be more predictable than outward and passive head movements.Results: After validation, results of 57 tested subjects were analyzed. Mean VOR gain was significantly lower for inward passive compared with outward passive head impulses (p < 0.001), and it was higher for active compared with passive head impulses (both inward and outward) (p ≤ 0.024). Mean latency of the first saccade was significantly shorter for inward active compared with inward passive (p ≤ 0.001) and for inward passive compared with outward passive head impulses (p = 0.012). Mean PR-score was only significantly higher in active outward than in active inward head impulses (p = 0.004).Conclusion: For SHIMP, a higher predictability in head movements lowered gain only in passive impulses and shortened latencies of compensatory saccades overall. For active impulses, gain calculation was affected by short-latency compensatory saccades, hindering reliable comparison with gains of passive impulses. Predictability did not substantially influence grouping of compensatory saccades.

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