BACKGROUND The vertical vestibulo-ocular reflex (VOR) may be impaired in internuclear ophthalmoplegia (INO) as the medial longitudinal fasciculus (MLF) conveys VOR-signals from the vertical semicircular canals. It has been proposed that signals from the contralesional posterior semicircular canal (PSC) are exclusively transmitted through the MLF, while for the contralesional anterior canal othe...

OBJECTIVES/HYPOTHESIS To aid in diagnosis of Meniere's disease (MD) during the attacks using caloric and head-impulse tests (HITs). STUDY DESIGN Retrospective case series review. METHODS We analyzed the results of bithermal caloric and HITs during the attacks in 16 patients with MD. Quantitative analyses of HITs were conducted using a magnetic search coil technique. RESULTS In unilateral ...

The semicircular canals (SCC) are fluid-filled inner ear structures designed to detect circular or angular motion. In this study we modeled three-dimensional biomechanical model of SCC and compared results with real patient case for the Benign Paroxysmal Positional Vertigo (BPPV) disease. The model consists of full 3D fluid-structure interaction incorporating particles, wall, cupula deformation...

This study aimed to define the acute electrophysiological effects of the perilymphatic perfusion of streptomycin in the sensory apparatus of the semicircular canals of the frog. The ampullary DC potential, the vestibular nerve multiunit discharge, the nerve DC potential and the unitary EPSP activity were recorded in isolated semicircular canals of the frog (Rana esculenta L). The results demons...

Hair cells are specialized sensory epithelial cells found in the inner ear (Figure1a). Inmammals, the inner ear contains the coiled cochlea as well as the vestibular apparatus, which includes two otolith organs (the utricle and the saccule) and three semicircular canals. The cochlea and the components of the vestibular apparatus are interconnected by fluid-filled tubes that are circular and con...

INTRODUCTION Oscillating the head about a spatial horizontal axis activates both the vertical semicircular canals (VC) and the otolith organs. It is generally assumed that in-phase modulation of unit firing rate (FR) with head position indicates convergent otolith input, while in-phase modulation with head velocity indicates VC input. The amplitude of FR modulation depends on head orientation i...

Introduction: vHIT test to assess the functioning of three semicircular canals. Objective: This study was designed to objectively assess the functioning of the three semicircular canals in individual with severe to profound sensorineural hearing loss using vHIT respectively. Methods: Twenty adult participants (40 ears) having severe to profound hearing loss ranging in age from 15-40 years in gr...

BACKGROUND Vibration to the head or neck excites vestibular and neck muscle spindle afferents. Can such vibrations improve the sensitivity of the subjective visual horizontal (SVH) test to chronic unilateral deficit of the vestibular system? DESIGN Controlled experimental study. SETTING Tertiary referral center. PATIENTS AND CONTROLS Thirteen healthy subjects and 23 patients with chronic ...

Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. ...