Ictal downbeat nystagmus in Ménière disease

Neurology ◽  
2020 ◽  
Vol 95 (17) ◽  
pp. e2409-e2417
Author(s):  
Sun-Uk Lee ◽  
Hyo-Jung Kim ◽  
Jeong-Yoon Choi ◽  
Ji-Soo Kim
Keyword(s):  
Semicircular Canals ◽  
Vestibular Evoked Myogenic Potentials ◽  
Slow Phase ◽  
Downbeat Nystagmus ◽  
Meniere Disease ◽  
Head Impulse ◽  
Slow Phase Velocity ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Menière Disease

ObjectiveTo determine the mechanism of ictal downbeat nystagmus in Ménière disease (MD), we compared the head impulse gain of the vestibulo-ocular reflex (VOR) for each semicircular canal between patients with (n = 7) and without (n = 70) downbeat nystagmus during attacks of MD.MethodsWe retrospectively analyzed the results of video-oculography, video head-impulse tests, and cervical vestibular-evoked myogenic potentials (VEMPs) in 77 patients with definite MD who were evaluated during an attack.ResultsPure or predominant downbeat nystagmus was observed in 7 patients (9%) with unilateral MD during the attacks. All 7 patients showed spontaneous downbeat nystagmus without visual fixation with a slow phase velocity ranging from 1.5 to 11.2°/s (median 5.4, interquartile range 3.7–8.5). All showed a transient decrease of the head impulse VOR gains for the posterior canals (PCs) in both ears (n = 4) or in the affected ear (n = 3). Cervical VEMPs were decreased in the affected (n = 2) or both ears (n = 2) when evaluated during the attacks. Downbeat nystagmus disappeared along with normalization of the VOR gains for PCs after the attacks in all patients. During the attacks, the head impulse VOR gains for the PC on the affected side were lower in the patients with ictal downbeat nystagmus than in those without (Mann-Whitney U test, p < 0.001), while the gains for other semicircular canals did not differ between the groups.ConclusionDownbeat nystagmus may be observed during attacks of MD due to an asymmetry in the vertical VOR or saccular dysfunction. MD should be considered in recurrent audiovestibulopathy and ictal downbeat nystagmus.

scholarly journals Unusual Vestibulo-Ocular Reflex Responses in Patients With Peripheral Vestibular Disorders Detected by the Caloric Step Stimulus Test

2020 ◽  
Vol 11 ◽  
Author(s):  
Motomu Honjo ◽  
Keiji Honda ◽  
Takeshi Tsutsumi
Keyword(s):  
Time Constant ◽  
Slow Phase ◽  
Vestibular Disorders ◽  
Rapid Rise ◽  
Meniere Disease ◽  
Time Constants ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Menière Disease ◽  
Normal Controls

The caloric step stimulus test consists of the changes in head position from the sitting to supine positions and continuous caloric irrigation. This test can provide a single labyrinth with a stimulus similar to constant head acceleration in rotational testing and, therefore, can evaluate vestibulo-ocular reflex (VOR) dynamics more precisely than can conventional methods. To assess the clinical utility of the test in the assessment of the VOR dynamics of diseases, we performed the test in patients with peripheral vestibular disorders, including sudden idiopathic hearing loss, vestibular neuritis, Meniere disease, vestibular Meniere disease, or chronic unilateral idiopathic vestibulopathy and normal controls. Slow-phase eye velocity (SPV) was measured with videonystagmography. We fitted the time course of SPV across 2 min to a mathematical model containing two exponential components and time constants: the caloric step VOR time constant (T1) and caloric step VOR adaptation time constant (T2). All responses of normal controls (n = 15 ears) were fit to the model. Several responses of the 101 ears of the patients differed from the time courses predicted by the model. We divided the data of 116 ears into four patterns based on SPV, T1, and T2. The thresholds for the classification were determined according to the lower limits of the capability of curve fitting for SPV and the upper limits of normal controls for T1 and T2. Seventy-eight ears followed pattern A (normal T1 and T2): the SPV trajectory formed a rapid rise with subsequent decay. Nineteen followed pattern B (normal T1 and prolonged T2): the SPV trajectory formed a rapid rise without decay. Six followed pattern C (prolonged T1 and T2): the SPV trajectory formed a slow rise. Thirteen ears followed pattern D: a low VOR response. There were no significant differences in time constants between the affected and healthy ears in patients with each disease. However, prolonged T1 and T2 were significantly more frequent in the affected ears than the healthy ears. In conclusion, the caloric step stimulus test can be potentially useful in detecting unusual VOR responses and thus reflect some pathological changes in the vestibular system.

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

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.

scholarly journals Cervical vestibular evoked myogenic potentials and video head impulse test in Ménière disease

2020 ◽  
Vol 86 (5) ◽  
pp. 534-544 ◽  
Author(s):  
Thaís Alvares de Abreu e Silva Grigol ◽  
Karen de Carvalho Lopes ◽  
Fernando Freitas Ganança
Keyword(s):  
Vestibular Evoked Myogenic Potentials ◽  
Head Impulse Test ◽  
Video Head Impulse Test ◽  
Meniere Disease ◽  
Head Impulse ◽  
Menière Disease

Asymmetry of Vestibulo-Ocular Reflex in the Cat

1985 ◽  
Vol 93 (5) ◽  
pp. 597-600 ◽  
Author(s):  
John H. Anderson ◽  
Stephen L. Liston
Keyword(s):  
Eye Movements ◽  
Semicircular Canals ◽  
Whole Body ◽  
Slow Phase ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Vertical Semicircular Canals

Vertical eye movements were recorded in alert, restrained cats that were subjected to whole-body rotations which stimulated the vertical semicircular canals. The results showed a significant asymmetry between the upward and downward slow-phase eye movements, which suggests differences in the CNS processing of vertical canal inputs vis-à-vis the vestibulo-ocular reflex.

Impaired vestibular responses in internuclear ophthalmoplegia

Neurology ◽  
2017 ◽  
Vol 89 (24) ◽  
pp. 2476-2480 ◽  
Author(s):  
Seo-Young Choi ◽  
Hyo-Jung Kim ◽  
Ji-Soo Kim
Keyword(s):  
Vestibular Evoked Myogenic Potentials ◽  
Medial Longitudinal Fasciculus ◽  
Subjective Visual Vertical ◽  
Internuclear Ophthalmoplegia ◽  
Horizontal Canal ◽  
Head Impulse ◽  
Ocular Tilt Reaction ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Visual Vertical

Objective:To determine the role of the medial longitudinal fasciculus (MLF) in conveying vestibular signals.Methods:In 10 patients with isolated acute unilateral internuclear ophthalmoplegia (INO) due to an acute stroke, we performed comprehensive vestibular evaluation using video-oculography, head impulse tests with a magnetic search coil technique, bithermal caloric tests, tests for the ocular tilt reaction, and measurements of subjective visual vertical and cervical and ocular vestibular evoked myogenic potentials (VEMPs).Results:The head impulse gain of the vestibulo-ocular reflex (VOR) was decreased invariably for the contralesional posterior canal (PC) (n = 9; 90%) and usually for the ipsilesional horizontal canal (n = 5; 50%). At least one component of contraversive ocular tilt reaction (n = 9) or contraversive tilt of the subjective visual vertical (n = 7) were common along with ipsitorsional nystagmus (n = 5). Cervical or ocular VEMPs were abnormal in 5 patients.Conclusions:The MLF serves as the main passage for the high-acceleration VOR from the contralateral PC. The associations and dissociations of the vestibular dysfunction in our patients indicate variable combinations of damage to the vestibular fibers ascending or descending in the MLF even in strokes causing isolated unilateral INO.

scholarly journals Evaluation of Interexaminer Variability in Video Head Impulse Test Results

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.

Alexander's Law Revisited

2008 ◽  
Vol 100 (1) ◽  
pp. 154-159 ◽  
Author(s):  
Benjamin Jeffcoat ◽  
Alexander Shelukhin ◽  
Alex Fong ◽  
William Mustain ◽  
Wu Zhou
Keyword(s):  
Cold Water ◽  
Warm Water ◽  
Slow Phase ◽  
Neural Integrator ◽  
The Gaze ◽  
Slow Phase Velocity ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Alexander’S Law ◽  
Peripheral Inhibition

Alexander's Law states that the slow-phase velocity of the nystagmus caused by unilateral vestibular lesion increases with gaze in the beat direction. Two studies have shown that this gaze effect is generalized to the nystagmus caused by unilateral cold water irrigation. This indicates that the gaze effect is not the result of central changes associated with a peripheral lesion but rather because of unilateral vestibular peripheral inhibition. In this study, we show that there is a similar gaze effect on the nystagmus produced by unilateral warm water ear irrigation. Furthermore, we examined the two hypotheses of Alexander's Law proposed in the two studies. One hypothesis is based on the gaze-dependent modulation of the vestibulo-ocular reflex (VOR) response to unbalanced canal input. The other hypothesis, however, is based on the leaky neural integrator caused by unilateral vestibular peripheral inhibition. These two hypotheses predict the same gaze effect on the nystagmus produced by cold water irrigation, but opposite gaze effects on the nystagmus produced by warm water irrigation. Our results support the first hypothesis and suggest that the second hypothesis needs to be modified.

A review of the effects of space flight on the asymmetry of vertical optokinetic and vestibulo-ocular reflexes

2003 ◽  
Vol 13 (4-6) ◽  
pp. 255-263
Author(s):  
Gilles Clément
Keyword(s):  
Phase Velocity ◽  
Optokinetic Nystagmus ◽  
Visual Stimulation ◽  
Head Movements ◽  
Slow Phase ◽  
Eye Position ◽  
Slow Phase Velocity ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Eye Velocity

Prolonged microgravity during orbital flight is a unique way to modify the otolith inputs and to determine the extent of their contribution to the vertical vestibulo-ocular reflex (VOR) and optokinetic nystagmus (OKN). This paper reviews the data collected on 10 astronauts during several space missions and focuses on the changes in the up-down asymmetry. Both the OKN elicited by vertical visual stimulation and the active VOR elicited by voluntary pitch head movements showed an asymmetry before flight, with upward slow phase velocity higher than downward slow phase velocity. Early in-flight, this asymmetry was inverted, and a symmetry of both responses was later observed. An upward shift in the vertical mean eye position in both OKN and VOR suggests that these effects may be related to otolith-dependent changes in eye position which, in themselves, affect slow phase eye velocity.

scholarly journals Oculomotor Abnormalities in Friedreich's Ataxia

1979 ◽  
Vol 6 (2) ◽  
pp. 167-172 ◽  
Author(s):  
T.H. Kirkham ◽  
D. Guitton ◽  
A. Katsarkas ◽  
L.B. Kline ◽  
E. Andermann
Keyword(s):  
Phase Velocity ◽  
Friedreich’S Ataxia ◽  
Friedreich's Ataxia ◽  
Motor Deficits ◽  
Slow Phase ◽  
Stimulus Velocity ◽  
Slow Phase Velocity ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Caloric Nystagmus

SummaryA clinical neuro-opthalmo-logical and electro-oculographic study was made on fourteen patients with Friedreich's ataxia. None had evidence of optic nerve dysfunction. No patient complained of oscillopsia although all had ocular motor deficits of varying degrees, which appeared to be related to the severity of the general manifestations of the disease. The defects comprised square wave jerks, jerky pursuit with inability to maintain eccentric gaze resulting in gaze paretic nystagmus and rebound nystagmus. There was failure to suppress by fixation the vestíbulo-ocular reflex. The slow phase velocity of caloric nystagmus was always of reduced velocity. There was inability to augment the slow phase velocity of optokinetic nystagmus with increasing stimulus velocity. Abnormalities of the saccadic system were manifest particularly as hypermetria. These signs in combination are suggestive of disease involving the cere be I lar flocculus and vermis or their brain stem connections. No abnormalities were found in 17 parents or siblings.

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