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

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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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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Vestibulo-ocular reflex gain values in the suppression head impulse test of healthy subjects

The Laryngoscope ◽

10.1002/lary.27107 ◽

2018 ◽

Vol 128 (10) ◽

pp. 2383-2389 ◽

Cited By ~ 9

Author(s):

Jorge Rey-Martinez ◽

Izaskun Thomas-Arrizabalaga ◽

Juan Manuel Espinosa-Sanchez ◽

Angel Batuecas-Caletrio ◽

Gabriel Trinidad-Ruiz ◽

...

Keyword(s):

Healthy Subjects ◽

Head Impulse Test ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain

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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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Normative values of vestibulo-ocular reflex gain obtained through Video Head Impulse Test: an integrative literature review

Revista CEFAC ◽

10.1590/1982-0216/20202264320 ◽

2020 ◽

Vol 22 (6) ◽

Author(s):

Patricia Oyarzún Díaz ◽

Sebastián Rivera Retamal ◽

Sergio Jiménez Cofré ◽

Hugo Segura Pujol

Keyword(s):

Cochrane Library ◽

Normative Values ◽

Head Impulse Test ◽

Original Research ◽

Video Head Impulse Test ◽

Head Impulse ◽

Ocular Reflex ◽

Object Distance ◽

Vestibulo Ocular Reflex ◽

Reflex Gain

ABSTRACT Purpose: to identify and analyze the available evidence on the reference values of the vestibulo-ocular reflex gain obtained with the video head impulse test. Methods: an integrative review based on the PRISMA protocol, searching the ProQuest, EBSCO, PubMed, ScienceDirect, Cochrane Library, LILACS, and SciELO databases with keywords. The studies included were original research articles, systematic reviews, and meta-analyses published since 2009, involving humans, written in English, Spanish and/or Portuguese. Results: 10,250 studies related to the keywords were found. Of these, 10 articles met the inclusion criteria and were analyzed following the CADE protocol. On the horizontal plane, the values ranged from 0.80 to 1.06, while on the right anterior/left posterior and on the left anterior/right posterior planes, the values ranged from 0.80 to 1.03. Other relevant data for obtaining the gain were analyzed, such as the number of impulses, the assessor’s experience, the patient-object distance, and the percentage of asymmetry. Conclusion: little research on the theme, recently developed and published, mostly in European countries, was found. This shows the need for a greater number of studies to strengthen the scientific evidence.

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Report of oscillopsia in ataxia patients correlates with activity, not vestibular ocular reflex gain

Journal of Vestibular Research ◽

10.3233/ves-210106 ◽

2021 ◽

pp. 1-9

Author(s):

Jennifer L. Millar ◽

Michael C. Schubert

Keyword(s):

Cerebellar Ataxia ◽

Head Rotation ◽

Gait Velocity ◽

Head Impulse Test ◽

Healthy Controls ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibular Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain

BACKGROUND: Patients with cerebellar ataxia report oscillopsia, “bouncy vision” during activity, yet little is known how this impacts daily function. The purpose of this study was to quantify the magnitude of oscillopsia and investigate its relation to vestibulo-ocular reflex (VOR) function and daily activity in cerebellar ataxia. METHODS: 19 patients diagnosed with cerebellar ataxia and reports of oscillopsia with activity were examined using the video head impulse test (vHIT), Oscillopsia Functional Index (OFI), and clinical gait measures. Video head impulse data was compared against 40 healthy controls. RESULTS: OFI scores in ataxia patients were severe and inversely correlated with gait velocity (r = –0.55, p < 0.05), but did not correlate with VOR gains. The mean VOR gain in the ataxic patients was significantly reduced and more varied compared with healthy controls. All patients had abnormal VOR gains and eye/head movement patterns in at least one semicircular canal during VHIT with passive head rotation. CONCLUSIONS: Patients with cerebellar ataxia and oscillopsia have impaired VOR gains, yet severity of oscillopsia and VOR gains are not correlated. Patients with cerebellar ataxia have abnormal oculomotor behavior during passive head rotation that is correlated with gait velocity, but not magnitude of oscillopsia.

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Efficacy of vestibulo-ocular reflex gain and refixation saccades of video head impulse test in identifying vestibular pathologies

Indian Journal of Otology ◽

10.4103/indianjotol.indianjotol_76_17 ◽

2017 ◽

Vol 23 (4) ◽

pp. 247 ◽

Cited By ~ 1

Author(s):

NirajKumar Singh ◽

Rajeshwari Govindaswamy ◽

Nirmala Jagadish

Keyword(s):

Head Impulse Test ◽

Video Head Impulse Test ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain

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Episodic Vestibulocerebellar Ataxia Associated with a CACNA1G Missense Variant

Case Reports in Neurology ◽

10.1159/000515974 ◽

2021 ◽

pp. 347-354

Author(s):

José Gazulla ◽

Silvia Izquierdo-Alvarez ◽

Emilio Ruiz-Fernández ◽

Alba Lázaro-Romero ◽

José Berciano

Keyword(s):

Missense Variant ◽

Absence Epilepsy ◽

Head Movements ◽

Spinocerebellar Ataxia Type ◽

Head Impulse Test ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain ◽

Disease Variant ◽

Successive Generations

Episodic vestibulocerebellar ataxias are rare diseases, frequently linked to mutations in different ion channels. Our objective in this work was to describe a kindred with episodic vestibular dysfunction and ataxia, associated with a novel CACNA1G variant. Two individuals from successive generations developed episodes of transient dizziness, gait unsteadiness, a sensation of fall triggered by head movements, headache, and cheek numbness. These were suppressed by carbamazepine (CBZ) administration in the proband, although acetazolamide and topiramate worsened instability, and amitriptyline and flunarizine did not prevent headache spells. On examination, the horizontal head impulse test (HIT) yielded saccadic responses bilaterally and was accompanied by cerebellar signs. Two additional family members were asymptomatic, with normal neurological examinations. Reduced vestibulo-ocular reflex gain values, overt and covert saccades were shown by video-assisted HIT in affected subjects. Hearing acuity was normal. Whole-exome sequencing demonstrated the heterozygous CACNA1G missense variant c.6958G>T (p.Gly2320Cys) in symptomatic individuals. It was absent in 1 unaffected member (not tested in the other asymptomatic individual) and should be considered likely pathogenic. CACNA1G encodes for the pore-forming, α1G subunit of the T-type voltage-gated calcium channel (VGCC), in which currents are transient owing to fast inactivation, and tiny, due to small conductance. Mutations in CACNA1G cause generalized absence epilepsy and adult-onset, dominantly inherited, spinocerebellar ataxia type 42. In this kindred, the aforementioned CACNA1G variant segregated with disease, which was consistent with episodic vestibulocerebellar ataxia. CBZ proved successful in bout prevention and provided symptomatic benefit in the proband, probably as a result of interaction of this drug with VGCC. Further studies are needed to fully determine the vestibular and neurological manifestations of this form of episodic vestibulocerebellar ataxia. This novel disease variant could be designated episodic vestibulocerebellar ataxia type 10.

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Vestibulo-ocular reflex and the head impulse test

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2012001200008 ◽

2012 ◽

Vol 70 (12) ◽

pp. 942-944 ◽

Cited By ~ 4

Author(s):

Eliana T. Maranhão ◽

Péricles Maranhão-Filho

Keyword(s):

Diagnostic Method ◽

Vestibular Dysfunction ◽

Head Impulse Test ◽

Emergency Rooms ◽

Brainstem Infarction ◽

Head Impulse ◽

Ocular Reflex ◽

Peripheral Vestibulopathy ◽

Vestibulo Ocular Reflex

The authors highlights the importance of the vestibulo-ocular reflex examination through the head impulse test as a diagnostic method for vestibular dysfunction as well as, and primarily, a bedside semiotic resource capable of differentiating between acute peripheral vestibulopathy and a cerebellar or brainstem infarction in emergency rooms.

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