Vestibular Activation In Benign Paroxysmal Positional Vertigo And Superior Semicircular Canal Dehiscence
Funder
National Health and Medical Research Council
Funding Amount
$340,350.00
Summary
Vestibular Activation in Benign Paroxysmal Positional Vertigo and Superior Semicircular Canal Dehiscence The aim of this project is to study the pathological activation of the vestibular system in benign paroxysmal positional vertigo and superior canal dehiscence in order to achieve an improved diagnosis in both conditions and a more effective treatment for benign paroxysmal positional vertigo. These diseases provide unique opportunities to study unilateral activation of an otherwise normal huma ....Vestibular Activation in Benign Paroxysmal Positional Vertigo and Superior Semicircular Canal Dehiscence The aim of this project is to study the pathological activation of the vestibular system in benign paroxysmal positional vertigo and superior canal dehiscence in order to achieve an improved diagnosis in both conditions and a more effective treatment for benign paroxysmal positional vertigo. These diseases provide unique opportunities to study unilateral activation of an otherwise normal human vestibular system. Benign paroxysmal positional vertigo and its variants is prevalent, especially amongst the elderly, as a major cause of dizziness and imbalance. These conditions describe a variety of vestibular lithiasis where free-floating otoconia misplaced in a semicircular canal cause abnormal deflection of the cupula, resulting in activation of the semicircular canal in a vestibular system during changes in gravitational head position. This study endeavours to develop a scientific basis for accurate diagnosis of benign paroxysmal positional vertigo and its variants. Online real-time 3-D recording and vector analysis of the nystagmus could be adapted to a 3-D video-oculography system for a more systematic approach to diagnosis and treatment. Thus, we aim to develop and trial a suitable particle repositioning manoeuvre using a mechanical device as treatment for patients who did not respond to the clinical Epley or Semont manoeuvre. Superior semicircular canal dehiscence permits sound or pressure to abnormally activate the vestibular system. In the superior canal dehiscence study, we seek to develop a more sensitive diagnostic test. If the click-evoked 3-D VOR is due to direct activation of the otoliths, then it offers an avenue to examine otolithic function. Understanding the mechanism of unilateral activation of a normal human vestibular system is important for the development of implantable vestibular prosthesis.Read moreRead less
Comprehensive Clinical Tests Of Vestibular Function To Track Vestibular Compensation And Meniere’s Disease
Funder
National Health and Medical Research Council
Funding Amount
$390,625.00
Summary
This Project will apply new, fast, safe, comprehensive, balance tests we have developed to measure the function of the balance receptors of the inner ear. We will track changes in balance function during disease and recovery in the many, and increasing, number of Australian patients with balance disorders. These tests will give us insight into changes in the inner ear associated with severe attacks of vertigo and why some patients recover so poorly after damage to inner ear balance receptors.
Combined linear and angular head movements are integral components of our natural head movements. The vestibular sensory apparatus in the labyrinth of the inner ear, which comprises three semicircular canals and two otoliths acts as an inertial guidance system during head motion. The vestibular sensors mediate the angular and linear vestibulo-ocular reflexive eye movements imperative to stabilise vision during the head motions. However, it is unclear how these responses to sudden linear and angu ....Combined linear and angular head movements are integral components of our natural head movements. The vestibular sensory apparatus in the labyrinth of the inner ear, which comprises three semicircular canals and two otoliths acts as an inertial guidance system during head motion. The vestibular sensors mediate the angular and linear vestibulo-ocular reflexive eye movements imperative to stabilise vision during the head motions. However, it is unclear how these responses to sudden linear and angular motion in three dimensions are combined and processed. Diseases of the inner ear can produce incapacitating visual and balance disturbances, yet the normal function of some of the inner ears receptors, in particular the otoliths, cannot be easily tested. Clinical evidence has shown that patients with incapacitating attacks of vertigo can have impairment of either or both the semicircular canals and the otoliths. The aim of this project is to measure quantitatively the semicircular canal-otolith response to transient, high-acceleration combined linear-angular head movements to find a reliable way to test the otolith function. Based on physiological principles and my preliminary experiment, we plan to use an off-axis head rotation procedure, a three-dimensional eye movement recordings and vector analysis technique to assess the linear and angular vestibulo-ocular reflex response from the otoliths and semicircular canals in the labyrinth. The practical significance of answers to these questions is that they will characterise the combined linear and angular vestibulo-ocular reflex responses that stabilise vision during transient head movements. It will provide us with a greater understanding of the visual disturbance that patients experienced during these kinds of head movements following vestibular disease or surgery. Measurement of the linear vestibulo-ocular reflex may also provide a diagnostic test of otolith function clinically in disease states.Read moreRead less