Search results for "Labyrinth"
showing 10 items of 54 documents
Preserved visual-vestibular interaction in patients with bilateral vestibular failure
2004
Background: During caloric vestibular stimulation, subjects showed bilateral activation of the vestibular cortex in the posterior insula and retroinsular region as well as concurrent deactivation of visual cortex areas bilaterally. This finding was the basis for the concept of a reciprocal inhibitory interaction between the vestibular and the visual systems. Objective: To analyze the modulations of this activation and deactivation pattern in patients with loss of vestibular input, that is, in patients with bilateral vestibular failure (BVF). Methods: Modulations of regional cerebral blood flow (rCBF) in PET were measured in nine patients with BVF and compared with those in healthy volunteer…
Diagnostic performance of reformatted isotropic thin-section helical CT images in the detection of superior semicircular canal dehiscence
2017
Purpose The purpose of this article is to assess the diagnostic performance of computed tomography (CT) reformatted images for detection of superior semicircular canal (SSC) dehiscence. Material and methods Forty-two patients, with sound- and/or pressure-induced vestibular symptoms, and 42 control participants underwent helical CT examination with a highly collimated beam (0.5 mm). Reformatted images of the vestibular labyrinth were obtained in the standard axial and coronal planes (group A images), and in a plane parallel and perpendicular to the SSC (group B images). Diagnostic performance obtained by evaluating the group A images alone and the group B images alone was analyzed by using t…
Vestibular evoked myogenic potential findings in multiple sclerosis.
2013
Abstract Introduction Multiple sclerosis is an inflammatory disease involving the occurrence of demyelinating, chronic neurodegenerative lesions in the central nervous system. We studied vestibular evoked myogenic potentials (VEMPs) in this pathology, to allow us to evaluate the saccule, inferior vestibular nerve and vestibular-spinal pathway non-invasively. Methods There were 23 patients diagnosed with multiple sclerosis who underwent VEMP recordings, comparing our results with a control group consisting of 35 healthy subjects. We registered p13 and n23 wave latencies, interaural amplitude difference and asymmetry ratio between both ears. Subjects also underwent an otoscopy and audiometric…
Pontine lesions mimicking acute peripheral vestibulopathy
1999
OBJECTIVES Clinical signs of acute peripheral vestibulopathy (APV) were repeatedly reported with pontine lesions. The clinical relevance of such a mechanism is not known, as most studies were biased by patients with additional clinical signs of brainstem dysfunction. METHODS Masseter reflex (MassR), blink reflex (BlinkR), brainstem auditory evoked potentials (BAEPs), and DC electro-oculography (EOG) were tested in 232 consecutive patients with clinical signs of unilateral APV. RESULTS Forty five of the 232 patients (19.4%) had at least one electrophysiological abnormality suggesting pontine dysfunction mainly due to possible vertebrobasilar ischaemia (22 patients) and multiple sclerosis (ei…
Vestibular-evoked myogenic potentials in "vestibular migraine" and Menière's disease: a sign of an electrophysiological link?
2009
Characterizations of the signs and symptoms of "vestibular migraine" and of Meniere's disease seem to overlap, suggesting that both diseases might be due to a common peripheral vestibular dysfunction. Thus, the aim of the present study was to assess vestibular-evoked myogenic potentials (VEMPs) in both disorders to determine whether there might be an electrophysiological link between the two disorders. The amplitude and latency of VEMPs were measured from the sternocleidomastoid muscle in 63 patients with vestibular migraine (median age 47 years, range 24-70 years) and in 16 patients with Meniere's disease (median age 52 years, range 36-72 years), and compared with those of 63 sex- and age-…
Vestibular impairment in Charcot-Marie-Tooth disease type 4C.
2014
Charcot-Marie-Tooth disease type 4C (CMT4C) is a hereditary neuropathy with prominent unsteadiness. The objective of the current study is to determine whether the imbalance in CMT4C is caused only by reduced proprioceptive input or if vestibular nerve involvement is an additional factor. We selected 10 CMT4C patients and 10 age-matched and sex-matched controls. We performed a comprehensive evaluation of the vestibular system, including video Head Impulse Test, bithermal caloric test, galvanic stimulation test and skull vibration-induced nystagmus test. None of the patients experienced dizziness, spontaneous or gaze-evoked nystagmus, but all had significant vestibular impairment when tested …
Influence of nerve branch of origin and extracanalicular extension of the tumor on hearing after middle fossa removal of vestibular schwannoma
2007
Neither nerve branch of origin nor extracanalicular (up to 1 cm) extension of a vestibular schwannoma (VS) influence the postoperative hearing outcome in patients operated via a middle cranial fossa (MCF) approach.To test whether the nerve branch of tumor origin and an extracanalicular, up to 1 cm, tumor extension influences hearing outcome after MCF VS surgery.This was a retrospective case review of 50 patients with postoperative pure-tone audiogram (PTA) performed later than 90 days after surgery. Twenty patients had a superior vestibular nerve (SVN) tumor and 27 patients had an inferior vestibular nerve (IVN) tumor. In three patients the nerve branch of origin of the VS could not be uneq…
Perdre le fil: labyrinthes de la littérature française moderne
2009
From the day when Theseus killed the Minotaur, the Maze turned into a form in search of meaning, and became useless. As a result, one was enjoined to ascribe nw meanings to the empty strcuture. Modern writers, when confronted with such a void, will have explored all its possibilities: while some of them, like Michel Butor, dismiss the sacred dimensions, others, like Serge Doubrovsky, see in it the image of the self (the body, the psyche...), and others still, like Raymond Roussel, Alain Robbe-Grillet or Georges Pererc, make of the pure geometrical structure of the labyrinth an aesthetic model, and thus a mirror of the work of art. However, one still have to ask whether the labrinth is a val…
A Case Study on Vestibular Sensations in Driving Simulators.
2022
Motion platforms have been used in simulators of all types for several decades. Since it is impossible to reproduce the accelerations of a vehicle without limitations through a physically limited system (platform), it is common to use washout filters and motion cueing algorithms (MCA) to select which accelerations are reproduced and which are not. Despite the time that has passed since their development, most of these algorithms still use the classical washout algorithm. In the use of these MCAs, there is always information that is lost and, if that information is important for the purpose of the simulator (the training simulators), the result obtained by the users of that simulator will no…
Absorption And Transferring Of The Coghlear Fluids
1968
The perilymph is absorbed in the loose connective tissue of the modio-lum, the endolymph is absorbed in the planum limbi and the interstitial liquid of the organ of Corti in the inner spiral sulcus. The basin of the vein of the aqueduct of the cochlea in a fetal phase transfers almost only perilymph. When fully developed, many veins of the above-said basin are obliterated and the remaining ones transfer more blood than perilymph. From the interstitial spaces of the limbus the endolymph flows into the capillaries towards the inner auditory veins and the interstitial liquid of the organ of Corti flows towards the same veins by means of short lymphatic vessels.