Recovery of otolith function in patients with benign paroxysmal positional vertigo evaluated by sinusoidal off-vertical axis rotation

Lee

et al. 2021

JCM

Off-vertical axis rotation (OVAR) is a laboratory test to assess the otolith function. This study aimed to analyze the parameters of OVAR in patients with unilateral vestibular hypofunction (UVH) and bilateral vestibulopathy (BVP), and to correlate the parameters of OVAR with those of VEMPs. Ten healthy volunteers, 41 UVH, and 13 BVP patients performed OVAR. Bias component (BIC) and modulation component (MOC) of UVH and BVP patients were compared with those of healthy controls. BIC and MOC were correlated with amplitude and interaural difference (IAD) of cervical VEMP (cVEMP) and ocular VEMP (oVEMP). In UVH patients, the direction of BICs to affected side rotation were reversed and the absolute value of BICs were decreased when they were compared to healthy controls. In BVP patients, BICs were markedly attenuated. MOCs were not changed in UVH and BVP patients. There was no statistically significant correlation between VEMPs and OVAR.

Section: Discussioncontrasting

confidence: 75%

Parameters of Off-Vertical Axis Rotation in Unilateral and Bilateral Vestibulopathy and Their Correlation with Vestibular Evoked Myogenic Potentials

Lee

et al. 2021

JCM

“…Several studies have attempted to determine utricular (otolithic) abnormalities in BPPV, but they have produced inconsistent results 39-42. Patients with BPPV may exhibit abnormalities in vestibular evoked myogenic potentials, subjective visual horizontal, and gain during off-vertical axis rotation 40-42…”

Section: Pathomechanismmentioning

confidence: 99%

“…Patients with BPPV may exhibit abnormalities in vestibular evoked myogenic potentials, subjective visual horizontal, and gain during off-vertical axis rotation 40-42…”

Section: Pathomechanismmentioning

confidence: 99%

Benign Paroxysmal Positional Vertigo

2010

Benign paroxysmal positional vertigo (BPPV) is characterized by brief recurrent episodes of vertigo triggered by changes in head position. BPPV is the most common etiology of recurrent vertigo and is caused by abnormal stimulation of the cupula by free-floating otoliths (canalolithiasis) or otoliths that have adhered to the cupula (cupulolithiasis) within any of the three semicircular canals. Typical symptoms and signs of BPPV are evoked when the head is positioned so that the plane of the affected semicircular canal is spatially vertical and thus aligned with gravity. Paroxysm of vertigo and nystagmus develops after a brief latency during the Dix-Hallpike maneuver in posterior-canal BPPV, and during the supine roll test in horizontal-canal BPPV. Positioning the head in the opposite direction usually reverses the direction of the nystagmus. The duration, frequency, and symptom intensity of BPPV vary depending on the involved canals and the location of otolithic debris. Spontaneous recovery may be expected even with conservative treatments. However, canalithrepositioning maneuvers usually provide an immediate resolution of symptoms by clearing the canaliths from the semicircular canal into the vestibule.

“…The following could be plausible reasons for this finding. During OVAR, which induces eye movements by a combination of ScOR and OOR, the OOR moves the eyes in the direction opposite to that of gravity in the nose-up position, leading to an increase in the gain [7]. In contrast, in the nose-down position, the OOR moves the eyes in the direction of gravity, leading to a decrease in the gain [12].…”

Section: Discussionmentioning

confidence: 99%

“…Japan), the obtained eye velocity waveforms were smoothed. The relative amplitude of the eye and chair velocity were determined by fast Fourier transformation, and then the VOR gain was determined by the ratio of the eyer velocity to that of the chair [6,7]. A paired t-test was used for statistical analysis, and a P value less than 0.05 was considered significant.…”

Section: Global Journal Of Otolaryngologymentioning

confidence: 99%

Influence of Somatosensory Inputs to the Shoulder on the Semicircular-Ocular Reflex and Otolith-Ocular Reflex

Sasano¹

2021

GJO

Background: Visual, somatic, and vestibular sensations play an important role in maintaining body balance and stabilizing visual images.Objective: To clarify the influence of somatosensory input on the vestibulo-ocular reflex (VOR) using earth vertical axis rotation (EVAR) and off-vertical axis rotation (OVAR).Material and methods: The participants were 25 healthy adult volunteers. EVAR and OVAR (0.16 Hz with a maximal angular velocity of 60°/s) were performed both when they grasped a bar fixed to the rotating chair and when they did not.Results: The VOR gain was significantly higher in both the EVAR and OVAR groups when the bar was grasped than when it was not. There was a significant difference between VOR gain in OVAR (nose-up) and OVAR (nose-down) when the bar was not grasped; however, there was no difference between them when the bar was grasped.Conclusions: Somatosensory inputs have a stronger influence on VOR than otolith inputs. Therefore, vestibular rehabilitation using joint movements as somatosensory input may be an effective exercise method.