Live Imaging of the Dehydration Effect of Isosorbide on the Normal and Hydropic Guinea Pig Cochleae Using Optical Coherence Tomography.

Objective: To investigate the isosorbide-induced dehydration effect on the endolymphatic space by intratympanic administration of isosorbide.

Background: Isosorbide, an osmotic diuretic, is used orally as a typical conservative therapy for Menière's disease (MD) in Japan. The dehydration effect occurs 6 hours after isosorbide ingestion.

Live imaging and functional changes of the inner ear in an animal model of Meniere's disease.

The symptoms of Meniere's disease (MD) are generally considered to be related to endolymphatic hydrops (EH). There are many recent reports supporting the possibility that vasopressin (VP) is closely linked to the formation of EH in Meniere's disease. Based on this, we developed a clinically relevant animal model of Meniere's disease in which a VP type 2 receptor agonist was administered after electrocauterization of the endolymphatic sac.

Noisy galvanic vestibular stimulation has a greater ameliorating effect on posture in unstable subjects: a feasibility study.

Ameliorating effect of noisy galvanic vestibular stimulation (nGVS) on posture varies among subjects. In this feasibility study, we investigated the association between original postural instability and the ameliorating effect of nGVS on posture. Data were collected in a previously published study.

Noisy Galvanic Vestibular Stimulation Sustainably Improves Posture in Bilateral Vestibulopathy.

Patients with bilateral vestibulopathy (BV) suffer from persistent postural imbalance, leading to a marked decrease in quality of life and a higher risk of falls. However, so far, the effective treatments for BV are very limited. We examined whether long-term noisy galvanic vestibular stimulation (nGVS) keeps improving body balance after the cessation of the stimulus in BV patients.

Noisy vestibular stimulation increases gait speed in normals and in bilateral vestibulopathy.

Background: Galvanic vestibular stimulation delivered as zero-mean current noise (noisy GVS) has been shown to improve static and dynamic postural stability probably by enhancing vestibular information.

Objective: /Hypothesis: To examine the effect of an imperceptible level of noisy GVS on dynamic locomotion in normal subjects as well as in patients with bilateral vestibulopathy.

Methods: Walking performance of 19 healthy subjects and 12 patients with bilateral vestibulopathy at their preferred speed was examined during application of noisy GVS with an amplitude ranging from 0 to 1000 μA.

Clinical features of otolith organ-specific vestibular dysfunction.

Objective: To elucidate the clinical features and vestibular symptoms of patients with otolith organ dysfunction in the presence of normal function of the semicircular canals.

Methods: We reviewed the clinical records of 277 consecutive new patients with balance disorders who underwent testing of cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs) as well as caloric testing and video head impulse testing (vHIT).

Results: We identified 76 patients who showed normal caloric responses and normal vHIT findings in each SCC plane, but abnormal responses in cVEMP and/or oVEMP testing.

Effects of Peripheral Vestibular Dysfunction on Dynamic Postural Stability Measured by the Functional Reach Test and Timed Up and Go Test.

Objective: To investigate the influence of vestibular function on dynamic postural stability assessed by the functional reach test (FRT) and the timed up and go test (TUG).

Study Design: Retrospective study.

Setting: Tertiary referral center.

Tumor-induced Osteomalacia Caused by a Parotid Tumor.

A 77-year-old man was suspected of having tumor-induced osteomalacia (TIO) because of hypophosphatemia (1.9 mg/dL) and elevated serum fibroblast growth factor 23 (FGF23) level (186.9 pg/mL).

Noisy galvanic vestibular stimulation induces a sustained improvement in body balance in elderly adults.

Vestibular dysfunction causes postural instability, which is prevalent in the elderly. We previously showed that an imperceptible level of noisy galvanic vestibular stimulation (nGVS) can improve postural stability in patients with bilateral vestibulopathy during the stimulus, presumably by enhancing vestibular information processing. In this study, we investigated the after-effects of an imperceptible long-duration nGVS on body balance in elderly adults.

Vestibular Evoked Myogenic Potentials in Vestibular Migraine: Do They Help Differentiating From Menière's Disease?

Objective: To investigate whether both cervical and ocular vestibular myogenic potentials (cVEMPs and oVEMPs) to air-conducted sound (ACS) and bone-conducted vibration (BCV) can help to differentiate vestibular migraine (VM) and Menière's disease (MD).

Study Design: Retrospective study.

Settings: A tertiary referral center.

Dehydration effects of a V2 antagonist on endolymphatic hydrops in guinea pigs.

We investigated the influence of vasopressin type 2 receptor antagonist (OPC-41061; Tolvaptan) on experimentally induced endolymphatic hydrops (EH) in guinea pigs. In the first series, the endolymphatic sac (ES) of the left ear of all animals was electrocauterized. Four weeks after surgery, the animals were allocated to four groups: three systemic applications groups (saline, OPC 10 and 100 mg/kg) and a local round window (RW) OPC 1 mg/body application group.

Characteristics of vertigo and the affected vestibular nerve systems in idiopathic bilateral vestibulopathy.

Conclusion: Vertigo attacks in IBV patients involving both the superior and inferior vestibular nerve systems were significantly more severe than vertigo attacks in patients with selective involvement of the inferior vestibular nerve system alone.

Objective: To investigate the relationship between the frequency and duration of vertigo and the affected vestibular nerve system in idiopathic bilateral vestibulopathy (IBV).

Methods: This study categorized 44 IBV patients into the following three sub-groups according to the affected vestibular nerve system: superior, inferior, and mixed type.

Clinical characteristics of patients with abnormal ocular/cervical vestibular evoked myogenic potentials in the presence of normal caloric responses.

Objective: To investigate the clinical features and vestibular symptoms of patients with abnormal ocular vestibular evoked myogenic potentials (oVEMPs) and/or cervical VEMPs (cVEMPs) in the presence of normal caloric responses.

Study Design: Retrospective chart review.

Setting: Tertiary referral center.

The effect of aging on the center-of-pressure power spectrum in foam posturography.

To assess age-related frequency-domain characteristics of the sway of center of pressure (COP) in foam posturography, two-legged stance tasks were performed by 163 controls in 4 conditions: eyes open with and without foam rubber, and eyes closed with and without foam rubber. The areas under the curve (AUCs) of power spectral density of the COP were calculated across low frequency (≥0.02 Hz and <0.

Involvement of vestibular organs in idiopathic sudden hearing loss with vertigo: an analysis using oVEMP and cVEMP testing.

Objective: To investigate the extent of vestibular lesions in idiopathic sudden hearing loss (ISHL) with vertigo.

Method: We reviewed the clinical records of 25 consecutive new patients with ISHL with vertigo. We classified patients based on their pattern of vestibular dysfunction.

Power spectral analysis of postural sway during foam posturography in patients with peripheral vestibular dysfunction.

Objective: To assess the frequency-domain characteristics of postural instability caused by peripheral vestibular dysfunction by performing a power spectral analysis of the center of pressure (COP) sway during foam posturography.

Methods: Data were obtained from 78 patients and 163 controls. Two-legged stance tasks were performed in 4 conditions: eyes open with and without foam rubber, and eyes closed with and without foam rubber.

Type 1 allergy-induced endolymphatic hydrops and the suppressive effect of H1-receptor antagonist (olopatadine hydrochloride).

Objective: To investigate whether endolymphatic hydrops (EH) is experimentally induced by type 1 (or immediate) hypersensitivity allergic reaction and to investigate the inhibitory action of a histamine H(1)-receptor antagonist (olopatadine hydrochloride [OLO-Hy]) on allergic EH induced by systemic immune challenge with 2,4-dinitrophenylated-Ascaris (DNP-As).

Methods: The experimental animals were actively sensitized with DNP-As twice at a 4-week interval and were provoked by an injection of DNP-BSA including DNP-As 1 week after the second sensitization. The OLO-Hy (+) group received oral administration of OLO-Hy (30 mg/kg) 1 hour before the provocation, whereas the OLO-Hy (-) group received distilled water.

Idiopathic latent vestibulopathy: a clinical entity as a cause of chronic postural instability.

The objective of this study is to describe a new clinical entity of idiopathic latent vestibulopathy (ILV), in which patients have unilateral or bilateral vestibulopathy combined with unsteadiness but without episodic vertigo, auditory disturbance, or a medical history suggesting the presence of vestibulopathy. A retrospective study of 1,233 consecutive new outpatients was conducted. Two-legged stance tasks were performed by 11 patients identified as having ILV in four conditions: eyes open with and without foam rubber, and eyes closed with and without foam rubber.

The diagnostic value of vestibular evoked myogenic potentials in patients with Meniere's disease.

Objective: To estimate the sensitivity and specificity of vestibular evoked myogenic potentials (VEMPs) in comparison with caloric test in diagnosing Meniere's disease (MD) among patients with dizziness.

Methods: Data were retrospectively collected from 1,170 consecutive patients who underwent vestibular tests. Among them, 114 patients were diagnosed as having unilateral definite MD.

Evaluation of the internal structure of normal and pathological Guinea pig cochleae using optical coherence tomography.

Optical coherence tomography (OCT) makes it possible to visualize the internal structures of several organs, such as the eye, in vivo. Although visualization of the internal structures of the inner ear has been used to try and identify certain pathological conditions, attempts have failed mainly due to the thick bony capsule surrounding this end organ. After decalcifying the bony wall of the cochlea with ethylenediamine tetraacetic acid, we could clearly visualize its internal structures by using OCT.

Factors affecting postural instability in Meniere's disease.

Objective: To assess the influence of factors that can affect the postural instability of Ménière's disease (MD) patients.

Study Design: Case-control study.

Setting: Outpatient clinic in a university hospital.

Ocular vestibular evoked myogenic potentials in response to air-conducted sound and bone-conducted vibration in vestibular schwannoma.

Objective: To clarify the origin and pathways of ocular vestibular evoked myogenic potentials (oVEMPs) to air-conducted sound (ACS), we compared the results of oVEMPs with ACS, with oVEMPs with bone-conducted vibration (BCV), cervical VEMPs (cVEMPs) with ACS, and the caloric test in patients with unilateral vestibular schwannoma (VS).

Study Design: Retrospective review.

Setting: Tertiary referral center.

Postural stability in vestibular neuritis: age, disease duration, and residual vestibular function.

Objectives/hypothesis: To assess the influence of factors that can affect postural instability in vestibular neuritis (VN).

Study Design: Retrospective data collection study.

Methods: Foam posturography was performed in 58 VN patients.

Morphological and functional changes in a new animal model of Ménière's disease.

The purpose of this study was to clarify the underlying mechanism of vertiginous attacks in Ménière's disease (MD) while obtaining insight into water homeostasis in the inner ear using a new animal model. We conducted both histopathological and functional assessment of the vestibular system in the guinea-pig. In the first experiment, all animals were maintained 1 or 4 weeks after electrocauterization of the endolymphatic sac of the left ear and were given either saline or desmopressin (vasopressin type 2 receptor agonist).

Ocular vestibular evoked myogenic potential elicited from binaural air-conducted stimulations: clinical feasibility in patients with peripheral vestibular dysfunction.

Conclusion: Ocular vestibular evoked myogenic potentials (oVEMPs) to binaural air-conducted stimulation (ACS) may provide a convenient way of assessing the crossed vestibulo-ocular reflex in patients with vestibular dysfunction as well as in healthy subjects.

Objective: To investigate the clinical feasibility of using oVEMPs in response to binaural ACS to assess normal subjects and patients with vestibular dysfunction.

Methods: The study investigated 24 normal subjects (14 men and 10 women, aged from 23 to 60 years) and 14 patients with unilateral peripheral vestibular dysfunction.