Later, this was described as cerebellar ataxia and bilateral vestibulopathy (CABV) syndrome with a very characteristic clinical sign-positive visually enhanced vestibulo-ocular
reflex test (VVOR) .
(37) This may be multifactorial, with possible causes being cerebral visual impairment, imperfect vestibulo-ocular
reflex compensation and limited head control.
It is one of the most difficult balance problems to treat because nearly all patients experience long-term unsteadiness and oscillopsia due to disturbance of the bilateral vestibulo-ocular
Information from the vestibular system and their central pathways is integrated with visual and proprioceptive afferent nerve potentials to obtain gaze stabilization and postural stability via the vestibulo-ocular
and vestibulospinal reflexes, respectively.
In those cases where the prescription did not contain a specific diagnosis, an experienced physiotherapist evaluated each subject by means of a battery of clinical oculomotor (ocular alignment and tests of Skew, ocular range of motion, smooth pursuit, volitional saccades, and vergence) and vestibular tests (vestibulo-ocular
reflex cancellation test (VORc), head impulse test, head shaking test, or mastoid vibration test), thus ensuring that the disorder was primarily of the vestibular origin.
reflex (VOR) is a dynamic vestibular function, which helps humans to maintain balance and clear vision during head rotations or translations.
When the vestibulo-ocular
reflex (VOR) fails, head movements to the side of the lesion would initiate catch-up saccades to refixate the target on the retina.
Ocular vestibular evoked myogenic potential (oVEMP) reflect the excitatory utricular response and are used to evaluate the ascending vestibular pathway, as the crossed vestibulo-ocular
reflex (13) pointed to the shift of the contralateral eye to sound stimulation of the vestibular system (14), demonstrating that acoustic stimulation of the otoliths leads to oVEMP However, there still are doubts about whether oVEMP records changes exclusively in the utriculus or also in the sacculus (15).
In one study an enhanced vestibulo-ocular
reflex was observed in patients with Meniere's disease, compared to healthy individuals.
While c-VEMP mainly assesses saccular function and the vestibulo collic reflex, o-VEMP assesses utricular function and the vestibulo-ocular
Torsional eye movements consist of reflex movements driven by the vestibulo-ocular
system and cyclovergence movements driven by the vergence system.
Lasker, "Tonic and phasic contributions to the pathways mediating compensation and adaptation of the vestibulo-ocular
reflex," Journal of Vestibular Research: Equilibrium and Orientation, vol.