151 - 175 of 234
Number of results to display per page
TitleDescriptionType
151 Prolonged lid twitch in myasthenia gravisThis 50-yo-woman with ocular MG demonstrated a spontaneous and particularly prolonged eyelid twitch.Image/MovingImage
152 Provocative maneuvers (removal of fixation, vibration, head-shaking) to accentuate peripheral vestibular nystagmus)With an acute destructive process like vestibular neuritis that causes significant unilateral vestibular loss, spontaneous nystagmus is always present. However, over days to months, spontaneous nystagmus should resolve completely. In a patient with vestibular neuritis involving the right side, left-...
153 Pseudo-INOs in myasthenia gravisThis is a 55-yo-woman with an intermittent exotropia who had normal adduction OU, but clear lag of adducting saccades OD>OS with rapid horizontal saccades. This was much more apparent after repeat testing (ie, it was fatigable), and she wound up having ocular MG.Image/MovingImage
154 Pseudo-spontaneous nystagmus and bow and lean test in horizontal canal BPPVThis is a 70-year-old woman presenting to the Emergency Department with positional vertigo that was determined to be due to the apogeotropic variant of right horizontal canal (HC) benign paroxysmal positional vertigo (BPPV). When her head is in a neutral position with the head in axis with the trunk...
155 Range of Eye Movements and Evaluation for NystagmusRange: Assesses for motility deficit due to an ocular motor palsy, particularly if a posterior fossa localization is being considered; Nystagmus: Spontaneous nystagmus may or may not be noted and gaze-evoked nystagmus is common with posterior fossa lesions; nystagmus that is unidirectional in all di...Image/MovingImage
156 Rebound nystagmusThis is a 50-yo-man who presented for dizziness and imbalance. His exam demonstrated choppy smooth pursuit and VOR suppression as well as mild gait ataxia. There was mild right-beating nystagmus in right gaze and left-beating nystagmus in left gaze without vertical gaze-evoked nystagmus. Occasionall...Image/MovingImage
157 Relationship between semicircular canals and extraocular musclesFigure 1: When stimulated, each of the 6 angular acceleration detecting semicircular canals (3 on the right and 3 on the left) responds with a conjugate eye movement, with the vector(s) indicated below. PC=posterior canal; HC=horizontal (also known as lateral) canal; AC=anterior (also known as super...
158 Reversal of vertical nystagmus with convergence in anti-DPPX encephalitisThis is a man who initially presented with spontaneous upbeat and torsional nystagmus, which led to the diagnosis of anti-DPPX encephalitis (for further details on this patient's course and for a video of his nystagmus, see reference 1). Over 6-12 months, his spontaneous (mainly) upbeat nystagmus (U...
159 riMLF Syndrome from Artery of Percheron StrokeThis is a 65-yo-man who suffered the abrupt onset of loss of consciousness followed by difficulty looking down. MRI showed bilateral rostral midbrain strokes in the distribution of the artery of Percheron. He could not initiate downward saccades and had fair upward saccades. However, downward vestib...Image/MovingImage
160 Rotary Chair TestingRotary chair testing includes rotation around a vertical axis, and evaluates the horizontal semicircular canal vestibulo-ocular reflex (VOR). The patient sits in a mechanized chair with the head secured in a neutral position or in 30 degree forward flexion (to better isolate the horizontal canals)....
161 SaccadesThe examiner should note: conjugacy (a lag of the adducting eye may be seen with an INO); accuracy (posterior fossa lesions commonly produce dysmetria (overshooting or undershooting); velocity (if slow, may suggest a lesion of the burst neurons in the pons [PPRF - horizontally] or midbrain [riMLF - ...Image/MovingImage
162 Saccadic dysmetria and ocular lateropulsion in lateral medullary strokeThis is a 30-yo-man who suffered a right lateral medullary stroke. Examination showed saccadic hypermetria to the right (ipsilesional), hypometria to the left (contralesional)and rightward ocular lateropulsion (ipsilesional), common ocular motor features of the lateral medullary syndrome. Saccadic h...Image/MovingImage
163 Saccadic hypermetria and ipsipulsion (behind closed eyelids and with vertical saccades)This is a 40-year-old woman who experienced oscillopsia and vertical diplopia, due to spontaneous torsional nystagmus and a skew deviation (right hypotropia), respectively. The symptom onset was 7 months prior to these videos. MRI demonstrated ill-defined T2 and FLAIR hyperintensity signal changes i...
164 Saccadic intrusions with an intersaccadic intervalSeen here are patients with saccadic intrusions that have preserved intersaccadic intervals. Although square wave jerks (SWJ) are present in everyone to some degree at times, when prominent or when they interfere with vision, neurodegenerative conditions should be considered, mainly those involving ...Image/MovingImage
165 Saccadic pathways in the brainstem and cerebellum & mechanism for saccadic dysmetria in Wallenberg syndrome - Abnormal function of the brainstem/cerebellar saccadic pathways with a left Wallenberg syndromeThe end result of a lesion involving the climbing fibers within the left lateral medulla is deficient rightward saccades (contralesional hypometric saccades), and over-active leftward saccades (ipsilesional hypermetric saccades), and ipsilesional ocular lateropulsion given this baseline imbalance. M...
166 Saccadic pathways in the brainstem and cerebellum & mechanism for saccadic dysmetria in Wallenberg syndrome - Normal function of the brainstem/cerebellar saccadic pathwaysThe inferior cerebellar peduncle (ICP) carries climbing fibers to the dorsal vermis, and these fibers have an inhibitory influence over the Purkinje cells. These Purkinje cells normally inhibit the ipsilateral fastigial nucleus, and the fastigial nucleus projects to the contralateral inhibitory burs...
167 Saccadic smooth pursuit and vestibulo-ocular reflex suppression (VORS)This is a 20-yo-man who suffered a left MCA stroke years prior. Upon evaluation of his eye movements, saccades and all classes of eye movements were normal, although his smooth pursuit and VORS were choppy to the left (ipsilesional) and normal to the right. When pursuit and VORS (which are usually e...Image/MovingImage
168 Sagging eye syndrome and cerebellar disease in divergence insufficiencyThis is a 70-year-old woman who presented with diplopia at distance. Her exam demonstrated orthophoria at near with a fairly comitant 8-10 PD esotropia at distance without abduction paresis, consistent with divergence insufficiency (DI). With age, patients may develop an esodeviation greater at dist...
169 Sagittal section of the brainstem showing structures related to normal eyelid functionSeen here is a sagittal view of the brainstem, with the structures relevant to normal eyelid function highlighted. The M-group, which can be found medial to the riMLF (coordinates eye and lid movements), has (weak) projections to the facial nucleus for frontalis muscle contraction, and (strong) proj...
170 Sagittal section of the midbrain showing structures related to normal eyelid functionDuring a vertical saccade, the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF) is activated, which excites the superior rectus (SR) and inferior oblique (IO) (IIIrd nerve) subnuclei. Additionally, the riMLF activates the nearby M-group. The M-group's primary excitatory out...
171 Semicircular pathwaysOnce the semicircular canal fibers leave the peripheral labyrinth, they synapse in the ipsilateral vestibular nucleus, and then ascend to the ocular motor nuclei. This enables the vestibulo-ocular reflex to respond to head movements in the plane of any canal or combination of canals.
172 Sequelae of cerebellar hemorrhage - gaze-evoked nystagmus, alternating skew deviation and palatal tremorThis is a 75-yo-woman presenting with a gait disorder. Two years prior, she suffered a cerebellar hemorrhage. On examination, there were typical cerebellar ocular motor signs including gaze-evoked nystagmus, choppy smooth pursuit and VOR suppression, and saccadic dysmetria. There was also an alterna...Image/MovingImage
173 Sequential vasculopathic 3rd nerve palsies with preserved 4th nerve function65-yo-man with uncontrolled diabetes who developed sequential vasculopathic 3rd nerve palsies. In attempted downgaze, there's clear incyclotorsion OU suggestive of preserved 4th nerve function on both sides. There was complete recovery over months. Video shows bilateral 3rd nerve palsies with intact...Image/MovingImage
174 Skew deviation and spontaneous nystagmus due to posterior fossa lesionsThis is a 50-year-old woman who reported the abrupt onset of imbalance, right upper extremity incoordination and binocular vertical diplopia several months prior to her presentation to our clinic. On examination, she had a left hypertropia that was fairly comitant (measuring 5 prism diopters) assoc...
175 Slow abducting saccade in 6th nerve palsy40-yo-man with a right fascicular 6th nerve palsy due to stroke. There was improvement and only a minimal residual right abduction paresis OD by this visit, but still a relatively slow right abducting saccade seen in the video, especially apparent in the slow motion segment. Video shows slow abduct...Image/MovingImage
151 - 175 of 234