Focused Update on Clinical Testing of Otolith Organs.

Sensing gravity through the otolith receptors is crucial for bipedal stability and gait. The overall contribution of the otolith organs to eye movements, postural control, and perceptual functions is the basis for clinical testing of otolith function. With such a wide range of contributions, it is important to recognize that the functional outcomes of these tests may vary depending on the specific method employed to stimulate the hair cells.

The effects of COVID-19 on the vestibular system.

Introduction: The symptoms and severity of SARS-CoV-2 infection vary greatly across the spectrum, from asymptomatic infection to severe pneumonia with acute respiratory distress syndrome and even death. Dizziness is a frequently reported symptom of SARS-CoV-2 viral infection. However, the extent to which this symptom results from the effect of SARS-CoV-2 on the vestibular system remains unclear.

Acute onset of tinnitus in patients with sudden deafness.

Objective: We made hypotheses that tinnitus will appear more likely in patients with sudden deafness with superior hearing in unaffected ear or with more severe acute hearing loss.

Methods: A retrospective cohort study was performed. Five hundred forty-one patients were identified with idiopathic sudden sensorineural hearing loss (ISSHL) from January 1995 to August 2006.

Menière's disease caused by CGRP - A new hypothesis explaining etiology and pathophysiology. Redirecting Menière's syndrome to Menière's disease.

This paper provides a new hypothetical explanation for the etiopathology and pathophysiology of Menière's Disease (MD), which to date remain unexplained, or incompletely understood. The suggested hypothesis will explain the close connection of MD and Migraine, the coexistence of endolymphatic hydrops (ELH) and Menière attacks and the signs of inflammation detected in the inner ears of MD patients. Although as yet unproven, the explanations provided appear highly plausible and could pave the way for the generation of the first animal model of MD - an invaluable asset for developing new treatment strategies.

Correction to: Constant severe imbalance following traumatic otoconial loss: a new explanation of residual dizziness.

The original article was updated.

Constant severe imbalance following traumatic otoconial loss: a new explanation of residual dizziness.

Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo, caused by otoconia falling from the utricle into a semicircular canal (SCC). After successful repositioning maneuvers residual dizziness (RD) has been described and several reasons are used to explain RD. It can last for only a few days or weeks, but also much longer.

A pilot study investigating the association between chronic bilateral vestibulopathy and components of a clinical functional assessment tool.

Background: This study aimed to analyze the association between prospectively assessed falls and functional abilities in patients with bilateral vestibulopathy (BVP).

Methods: Nineteen BVP patients had functional abilities assessed at baseline with the expanded timed get-up-and-go (ETGUG) test. Falls were prospectively recorded with a monthly "fall calendar" over a one-year period.

Diagnosis and Treatment of Vestibular Neuritis/Neuronitis or Peripheral Vestibulopathy (PVP)? Open Questions and Possible Answers.

: The acute vestibular syndrome is a clinically defined entity consisting of vertigo or dizziness that develops acutely over minutes to hours and is accompanied by nausea/vomiting, gait instability, head motion intolerance, and nystagmus, while persisting over a day or more. When it is caused by a peripheral vestibular lesion and is not associated with clinically manifest auditory deficits, it is mostly labeled vestibular neuritis/neuronitis/neuropathy or sometimes peripheral vestibulopathy. Here, we propose hypotheses and discuss current research advances on viral or vascular factors in the pathogenesis, the recurrence, the site of lesion, old and new treatment options, contraindicated measures, the differential diagnosis, and the prognosis of vestibular neuritis/neuronitis/neuropathy or vestibulopathy.

About the pathophysiology of acute unilateral vestibular deficit - vestibular neuritis (VN) or peripheral vestibulopathy (PVP)?

Objective: To determine whether patients with acute unilateral peripheral vestibulopathy (PVP), often called "vestibular neuritis/neuronitis or neuropathy" (VN) have a vestibular lesion pattern consistent with the distribution of the neurological afferents.

Background: Much is known about the clinical nature of PVP, however less so about its etiology and pathogenesis. Due to the frequency with which VN is used to describe the syndrome, an inflammation of the vestibular nerve or of one of its branches is often assumed to be the cause of PVP, though there is insufficient data so far to support this assumption.

Ethanol consumption impairs vestibulo-ocular reflex function measured by the video head impulse test and dynamic visual acuity.

Ethanol affects many parts of the nervous system, from the periphery to higher cognitive functions. Due to the established effects of ethanol on vestibular and oculomotor function, we wished to examine its effect on two new tests of the vestibulo-ocular reflex (VOR): the video head impulse test (vHIT) and dynamic visual acuity (DVA). We tested eight healthy subjects with no history of vestibular disease after consumption of standardized drinks of 40% ethanol.

Health-related quality of life and emotional distress in patients with dizziness: a cross-sectional approach to disentangle their relationship.

Background: Dizziness is frequently encountered in medical practice, often takes a chronic course and can impair the health related quality of life (HRQoL). However results on the extent of this impairment of HRQoL are mixed. Furthermore, the relationship between dizziness and the HRQoL is only partially understood.

Reliability and validity of the extended timed-get-up-and-go test in patients with bilateral vestibular loss.

Background: The aim of his study was to evaluate the reliability and validity of the Expanded Timed Get-up-and-Go (ETGUG) test in patients with bilateral vestibular loss (BVL).

Methods: 21 BVL patients (58 ± 14 years) were recruited and measured twice by two raters. After a one hour break ETGUG was repeated by the first rater.

The effect of alcohol on cervical and ocular vestibular evoked myogenic potentials in healthy volunteers.

Objective: We investigated the effect of alcohol on the cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs). As alcohol produces gaze-evoked nystagmus (GEN), we also tested the effect of nystagmus independent of alcohol by recording oVEMPs during optokinetic stimulation (OKS).

Methods: The effect of alcohol was tested in 14 subjects over multiple rounds of alcohol consumption up to a maximum breath alcohol concentration (BrAC) of 1.

Vestibular stimulation attenuates unrealistic optimism.

Introduction: Unrealistic optimism refers to the pervasive tendency of healthy individuals to underestimate their likelihood of future misfortune, including illness. The phenomenon shares a qualitative resemblance with anosognosia, a neurological disorder characterized by a deficient appreciation of manifest current illness or impairment. Unrealistic optimism and anosognosia have been independently associated with a region of right inferior frontal gyrus, the pars opercularis.

Effectiveness of systemic high-dose dexamethasone therapy for idiopathic sudden sensorineural hearing loss.

Objective: To evaluate the effectiveness of systemic high-dose dexamethasone therapy for sudden sensorineural hearing loss in comparison to the previous treatment regimen at our clinic with systemic prednisone 100 mg daily for 7 days analyzed in a previous study.

Methods: We conducted a retrospective review of an electronic patient data base of 79 patients with idiopathic sudden sensorineural hearing loss. The standard treatment was orally applied dexamethasone (1st to 3rd day: 40 mg daily, 4th to 6th day: 10 mg daily) in an ambulant setting.

Eye position dependency of nystagmus during constant vestibular stimulation.

Alexander's law, the eye position dependency of nystagmus due to peripheral vestibular lesions, has been hypothesized to occur due to adaptive changes in the brainstem velocity-to-position neural integrator in response to non-reciprocal vestibular stimulation. We investigated whether it develops during passive head rotations that produce constant nystagmus for >35 s. The yaw rotation stimulus consisted of a 1-s acceleration (100°/s(2)), followed by a lower acceleration ramp (starting at 7.

A re-examination of the time constant of the oculomotor neural integrator in human.

We studied the horizontal oculomotor neural integrator in healthy human subjects during gaze holding in darkness. We found large variability among subjects with respect to the estimated time constants and the integrator's null position. We also found that individual subjects could demonstrate significantly nonlinear drift velocities as a function of eye position.

A mechanism for eye position effects on spontaneous nystagmus.

In acute stages of unilateral vestibular deficit, the imbalanced tonic activity on vestibular afferents evokes spontaneous nystagmus. The slow-phase velocity of this nystagmus varies with eye position, such that it is smaller when looking in the direction of slow-phases. The neural mechanism for this behavior is still not understood.

Development of eye position dependency of slow phase velocity during caloric stimulation.

The nystagmus in patients with vestibular disorders often has an eye position dependency, called Alexander's law, where the slow phase velocity is higher with gaze in the fast phase direction compared with gaze in the slow phase direction. Alexander's law has been hypothesized to arise either due to adaptive changes in the velocity-to-position neural integrator, or as a consequence of processing of the vestibular-ocular reflex. We tested whether Alexander's law arises only as a consequence of non-physiologic vestibular stimulation.

A dynamic model for eye-position-dependence of spontaneous nystagmus in acute unilateral vestibular deficit (Alexander's Law).

Spontaneous nystagmus (SN) is a symptom of acute vestibular tone asymmetry. Alexander's Law (AL) states that slow-phase velocity of SN is higher when looking in the direction of fast-phases of nystagmus and lower in the slow-phase direction. Earlier explanations for AL predict that during SN, slow-phase eye velocity is a linear function of eye position, increasing linearly as eye deviates towards the fast-phase direction.

Mutation analysis of Netrin 1 and HMX3 genes in patients with superior semicircular canal dehiscence syndrome.

Conclusion: In spite of its absence in the control population, there is questionable evidence for the alteration c.114C->T in the HMX3 gene being implicated in the development of superior semicircular canal dehiscence (SSCD). However, the concept of a complex disease is valid for SSCD and a possible molecular origin can neither be confirmed nor excluded by the results of this study.

Gaze strategies for avoiding obstacles: Differences between young and elderly subjects.

Visual input is highly relevant for safely stepping over obstacles. In this study, gaze-behaviour was investigated in elderly, middle-aged and young subjects as they walked on a treadmill repeatedly stepping over obstacles, which approached either on the right or left side. In between obstacle-steps, subjects visually fixated a target N or F located two or four steps ahead on the floor, respectively.

Is superior canal dehiscence congenital or acquired? A case report and review of the literature.

This article presents a detailed case report of a patient who was diagnosed with superior canal dehiscence at 37 years of age, but who had a suspicious history for that syndrome from at least 10 years of age. The authors hypothesize several reasons for this late diagnosis, with the goal of helping pediatricians, otolaryngologists, and neurologists consider this syndrome in their differential diagnosis of children, adolescents, or adults experiencing dizziness.

Relative diagnostic value of ocular vestibular evoked potentials and the subjective visual vertical during tilt and eccentric rotation.

Objective: We compared vibration-induced ocular vestibular evoked myogenic potentials (OVEMPs) with the visual vertical during whole-body roll tilt and eccentric rotation in healthy subjects and patients with unilateral vestibular loss, to determine which test was most sensitive in discriminating impaired utricle function.

Methods: OVEMPs and the visual vertical were measured in 11 patients and 11 healthy subjects. Visual vertical was measured during roll tilts between -9.

A new dynamic visual acuity test to assess peripheral vestibular function.

Objective: To evaluate a novel test for dynamic visual acuity (DVA) that uses an adaptive algorithm for changing the size of Landolt rings presented during active or passive head impulses, and to compare the results with search-coil head impulse testing.

Design: Prospective study in healthy individuals and patients with peripheral vestibular deficits.

Setting: Tertiary academic center.