The neck-eye reflex in patients with reduced vestibular and
optokinetic function.
The team was particularly interested in the brain regions involved in the
optokinetic reflex.
The test protocol included saccadic, tracking and
optokinetic eye movement evaluations, and recordings of gaze and spontaneous nystagmus, as well as head-shaking nystagmus, bithermal caloric, and positional tests.
Therefore, this study aims to describe and compare the results of ocular tests (saccadic movement, pendular tracking, and
optokinetic nystagmus) among the groups with dyslexia, learning disorders and control group.
A VNG battery of gaze, saccade, tracking,
optokinetic, static, and dynamic positional tests were performed followed by the Dix-Hallpike test.
The pendular calibration also tests the
optokinetic function of smooth pendular stimulus tracking (vide infra).
Asymmetric
optokinetic after-nystagmus induced by active or passive sustained head rotations.
This evaluation included tests for oculomotor systems integrity (saccadic, gaze,
optokinetic, and pursuit systems); tests for spontaneous, positional, and positioning nystagmus (Dix-Hallpike maneuver); and an ABBT.
In the study was investigated the effects of the menstrual cycle on visual-vestibular interaction by measuring
optokinetic function and postural stability at different phases of the cycle.
Other treatments for visual inattention include video feedback during treatment, training in visual imagery, diplopia, and vestibular, somatosensory, and
optokinetic stimulation.
Voluntary saccadic, smooth pursuit, visual (
optokinetic) input, or cervical input, can all control eye movements, and in order to test semicircular canal function specifically, the contribution of these additional sources of control must be excluded [2].
There are several different types of pathological, acquired nystagmus, of which the most common are spontaneous nystagmus (with or without fixation), positional or positioning nystagmus (occurring with or after head or body movement), gaze-evoked nystagmus (only present in specific eccentric eye gaze positions),
optokinetic nystagmus (only abnormal with lowered velocity of eye movements), pendular nystagmus (independent eyeball motion with vertical, horizontal and torsional nystagmus), seesaw nystagmus (alternating elevation and intorsion of one eye and simultaneous depression and extorsion of the other), and periodic alternating nystagmus, which is a strictly horizontal nystagmus that predictably oscillates in direction, amplitude and frequency.