pathological ocular tilt reaction

PURPOSE: Intra-ocular pressure (IOP) increases to double that of its normal level under full-body inversion, in part simulating high IOPs found in glaucoma and ocular hypertension. Inversion also simulates negative g-forces experienced in aerobatic maneuvers such as those produced during aerial combat. Studies using achromatic pattern-reversal visual evoked potentials (VEPs) have shown losses in response amplitude when subjects are inverted and IOP is increased. In other studies, chromatic, pattern-onset VEPs have been shown to be a sensitive and objective indicator of ocular and systemic pathology...

Internuclear ophthalmoplegia (INO) is a complex ocular motility disorder caused by damage to the medial longitudinal fasciculus. The occurrence of hemi-seesaw nystagmus in an INO patient has been reported rarely. This nystagmus may be caused by damage to the pathway from the contralateral vertical semicircular canal. The ocular tilt reaction is characterized by ipsilateral head and neck tilt, skew deviation, and ocular torsion. We report a patient who presented with hemi-seesaw nystagmus, ocular tilt reaction, and limb ataxia combined with an INO from a right focal pontine infarction...

BACKGROUND: To elucidate the mechanisms of paroxysmal ocular tilt reaction (OTR) from mesodiencephalic lesions by analyzing the associated ocular motor findings. METHODS: Two patients with paroxysmal ipsiversive OTR due to mesodiencephalic lesions underwent evaluation of associated ocular motor abnormalities and one of them had three-dimensional recording of eye motion. We also reviewed previously reported six patients with paroxysmal OTR. RESULTS: One patient showed contraversive torsional nystagmus during the paroxysms in association with vertical gaze limitation and vertical gaze-evoked nystagmus, which are consistent with baseline dysfunction and paroxysmal irritation of the interstitial nucleus of Cajal (INC) during the attacks...

The aim of the study was evaluation of central vestibular disorders in the scope of vestibular ocular reflexes disturbances in three planes: roll, pitch and yaw. The topo-diagnostic value of ocular tilt reaction, vertical nystagmus, rotational and horizontal nystagmus in central lesions was discussed.

In 20 consecutive patients with isolated medial medullary infarction, abnormal ocular motor findings included nystagmus (n = 8), ocular contrapulsion (n = 5), and contralesional ocular tilt reaction (n = 2). The nystagmus was ipsilesional (n = 4), gaze-evoked (n = 5), upbeating (n = 4), and hemiseesaw (n = 1). The ocular motor abnormalities may be explained by involvements of the nucleus prepositus hypoglossi, medial longitudinal fasciculus or efferent fibers from the vestibular nuclei, climbing fibers, and cells of the paramedian tracts...

PURPOSE: To describe a case of ocular tilt reaction caused by vasculitic lesions in the midbrain in a child with polyarteritis nodosa. DESIGN: Observational case report. METHODS: A 5-year-old girl with a chronic illness developed diplopia associated with a left head tilt, right hypertropia, torsional nystagmus, slowed vertical saccades and poor convergence. Fundoscopic examination demonstrated conjugate leftward torsion of the eyes consistent with a sustained ocular tilt reaction...

Single-neuron recording and electrical microstimulation suggest three roles for the mesencephalic reticular formation (MRF) in oculomotor control: 1) saccade triggering, 2) computation of the horizontal component of saccade amplitude (a feed-forward function), and 3) feedback of an eye velocity signal from the paramedian zone of the pontine reticular formation (PPRF) to higher structures. These ideas were tested using reversible inactivation of the MRF with pressure microinjection of muscimol, a GABA(A) agonist, in four rhesus monkeys prepared for chronic single-neuron and eye movement recording...

The delta 2 subunit of ionotropic glutamate receptors is expressed only in the cerebellar Purkinje cell. In mutant mice deficient in the delta 2 protein, cerebellar long-term depression and motor coordination are impaired. We examined behavioural plasticity in these mutant mice after unilateral vestibular destruction. After intratympanic injection of sodium arsanilate, the mice showed roll head tilt and their righting response under a rotation load was impaired. These symptoms improved with time. However, compensation of the righting response was retarded in the mutant mice...

The ocular tilt reaction (OTR) is a triad of head-eye synkinesis composed of head tilt, conjugate ocular torsion in the direction of head tilt, and skew deviation. The OTR represents a normal compensatory response to lateral head tilts and is produced by activation of the utricle of the lowermost ear. A pathological OTR results when otolith activity is unopposed as the result of injury to the opposite utricle or its nerve. Vertical diplopia may be the only symptom of OTR in patients who have undergone surgery involving the vestibuloacoustic nerve...

The fundamental pattern of coordinated eye-head roll motion is based upon utricular/saccular as well as vertical canal input, and mediated by the graviceptive pathways from the labyrinths via pontomedullary vestibular nuclei to the rostral midbrain tegmentum. The tonic bilateral graviceptive input stabilizes the eyes and head in the normal upright position. A unilateral lesion causes imbalance in vestibular tone in the roll plane which results in a tonic ipsiversive ocular tilt reaction (OTR). OTR, the triad of ipsilateral head tilt, skew deviation and ocular torsion, occurred as a tonic response (nonparoxysmal) persisting over months to years and was presumed to be due to upper brainstem lesions in 3 patients...

An otolith disorder is described in a patient with a subluxed stapes footplate. Otoneurological examination, including tympanoscopy, showed that nonphysiological mechanical stimulation of the otoliths by a (pathologically) hypermobile stapes footplate typically manifests with a pattern of sound-induced paroxysms of ocular tilt reaction (OTR), oscillopsia and postural imbalance (otolith Tullio phenomenon). The rare condition of sound-induced otolithic stimulation in an otherwise healthy young man offered a unique opportunity to investigate otolith reflex control of the eye, head and posture in man...

Midbrain lesions may give rise to the most complex eye movement disorders observed in clinical neurology. Three main types of dysfunction may be delineated, which may be combined: 1) intra-axial fascicular syndromes of the third and fourth cranial nerves; 2) nuclear syndromes of the third and fourth cranial nerves; 3) prenuclear and supranuclear syndromes, in which vertical gaze dysfunction is the main abnormality, but frequently with associated horizontal gaze dysfunction. The fascicular syndromes of the third nerve may be diagnosed when the oculomotor palsy is associated with some specific neurologic disturbances (syndromes of Weber, Benedikt, Claude-Nothnagel-Raymond-Cestan, Achard-Levi)...

Evidence is presented for a preliminary and speculative classification of central vestibular disorders of the brain stem according to the three major planes of action of the vestibuloocular reflex (VOR). 1. Disorders of the VOR in horizontal (yaw) plane: horizontal nystagmus-vertigo; 2. Disorders of the VOR in sagittal (pitch) plane: downbeat or upbeat nystagmus-vertigo; 3. Disorders of the VOR in frontal (roll) plane: ocular tilt reaction and lateropulsion.

The ocular motor abnormalities that commonly occur in Wallenberg's lateral medullary syndrome are often unappreciated. These abnormalities include signs of dysfunction of ocular alignment (skew deviation, ocular tilt reaction, and environmental tilt), various types of nystagmus, smooth pursuit and gaze-holding abnormalities (eye deviation, ipsipulsion or lateropulsion, and impaired contralateral pursuit), and saccadic abnormalities (ipsipulsion and torsipulsion). These impairments of ocular motor control and their proposed mechanisms are discussed...

The ocular tilt reaction, a synkinesis of ocular torsion, skew deviation, and head tilting, was a paroxysmal disorder in a patient with multiple sclerosis. In this distinctive pattern of eye and head motion, the 12 o'clock corneal meridians of both eyes are rotated conjugately in the direction of the lower skewed eye and the head is inclined laterally in the same direction. Paroxysmal activation of brain stem otolithic vestibular projections is proposed responsible for the dyskinesia. Coincident attacks of vertical and horizontal low amplitude pendular oscillation of the eyes produced elliptical nystagmus...