Search results for "VESTIBULAR"

Diagnosis and therapy of vestibular schwannoma.

2009

MRI studies are of paramount importance for diagnosis and follow-up measurements during conservative and postinterventional management of vestibular schwannomas (VS). MRI findings that convey important information for hearing-preservation VS surgery are: length of tumor-cochlear nerve contact, involvement of the internal auditory canal, incomplete filling of internal auditory canal, tumor size less than 15 mm and the intralabyrinthine signal intensity on 3DFT-CISS gradient-echo images. Functional neuro-otologic studies of facial nerve function, hearing and vestibular/balance function provide a valuable means of assessment of the actual impairment of the functional status of the VS patient. …

�ber ein Paraganglion vestibulare bei der Maus

1972

Im Ganglion vestibulare der Maus recht inkonstant vorkommende besondere Zellknotchen wurden licht- und elektronenmikroskopisch untersucht. Es wird angenommen, das die disseminiert auftretenden Zellgruppen ein nicht-chromaffines, parasympathogenes Paraganglion vestibulare darstellen, das den aus der Pars intermedia des N. facialis abgehenden Rr. communicantes cum N. statoacustico angehort. Diesem Paraganglion vestibulare wird eine (neuro-)sekretorische Funktion unterstellt und die Bedeutung der Paraganglien allgemein erortert.

On the Function of the Spiral Prominence

1967

The suppression of hematic circulation of the internal auditory artery of a guinea-pig causes the necrosis of all anatomic formations of the cochlear duct, with the exception of the organ of Corti of the vestibular segment. The author confirms his hypothesis about the origin of the cochlear endolymph and thinks that the prominence provides the vegetative life of the organ of Corti.

Sensorimotor aspects of high-speed artificial gravity: I. Sensory conflict in vestibular adaptation

2003

Short-radius centrifugation offers a promising and affordable countermeasure to the adverse effects of prolonged weightlessness. However, head movements made in a fast rotating environment elicit Coriolis effects, which seriously compromise sensory and motor processes. We found that participants can adapt to these Coriolis effects when exposed intermittently to high rotation rates and, at the same time, can maintain their perceptual-motor coordination in stationary environments. In this paper, we explore the role of inter-sensory conflict in this adaptation process. Different measures (vertical nystagmus, illusory body tilt, motion sickness) react differently to visual-vestibular conflict a…

A MODEL FOR VESTIBULAR FUNCTION IN ALTERED GRAVITATIONAL STATES

1979

ABSTRACT During evolution, the vestibular organ was made to serve mainly two purposes: 1) to guide eye movements during sharp turns, so that the point of fixation in the visual field can be kept steady, a function accomplished by the semicircular canal system and 2) to indicate the terrestrial vertical, so that upright posture and gait can be maintained even in the dark. The otolith system serves the latter purpose. Since the function of the semicircular canal system does not depend on gravity, it is not grossly disturbed by gravitational levels different from 1 g . The proper function of the otolith system depends entirely on the presence of a gravitational force vector of 9.8/m/sec2 direc…

Distribution of HSV-1 in Human Geniculate and Vestibular Ganglia: Implications for Vestibular Neuritis

2003

Influence of nerve of origin and tumor size of vestibular schwannoma on dynamic posturography findings.

2006

Condition 5-score (C5S) and vestibular ratio (VER) correlate, but condition-6-score (C6S) and mean overall balance score (MOBS) do not, with the size of an inferior vestibular nerve (IVN) vestibular schwannoma (VS). In IVN VS patients the visual system plays a major role in the maintenance of postural stability.To test whether the size of a superior vestibular nerve (SVN) or IVN VS, as measured on MRI scans, correlates with computerized dynamic platform posturography (CDPP) findings and whether CDPP findings could preoperatively predict the nerve of origin of the VS.This was a retrospective study. Seventy-five consecutive VS patients were evaluated. C5S, C6S, VER, and MOBS were evaluated. S…

Development and evolution of inner ear sensory epithelia and their innervation

2002

The development and evolution of the inner ear sensory patches and their innervation is reviewed. Recent molecular developmental data suggest that development of these sensory patches is a developmental recapitulation of the evolutionary history. These data suggest that the ear generates multiple, functionally diverse sensory epithelia by dividing a single sensory primordium. Those epithelia will establish distinct identities through the overlapping expression of genes of which only a few are currently known. One of these distinctions is the unique pattern of hair cell polarity. A hypothesis is presented on how the hair cell polarity may relate to the progressive segregation of the six sens…

Imaging of Vestibular Schwannoma With Prevalent Cystic Component

2009

Not available

A suggested role for secondary flow in the stimulation of the cochlear hair cell

1985

The mammalian Corti organ and the reptilian basilar papilla are structures with a curved surface, which vibrate in a fluid medium. This paper is concerned with the role played by the geometric shape of these organs in cochlear hydrodynamics. In association with vibrating structures such as these organs, it can be expected that a stationary current will be initiated due to a nonlinear phenomenon in the boundary layer known as secondary flow. This phenomenon may explain the source of the mechanical nonlinearity in the cochlea.