1/36. Disorders in cerebellar ocular motor control. II. Macrosaccadic oscillation. An oculographic, control system and clinico-anatomical analysis.A distinctive cerebellar ocular motor disorder, macrosaccadic oscillation, evolved simultaneously with an acute cerebellar syndrome in 4 patients, 2 with haemorrhagic metastatic melanoma deep in the vermis, a third with a presumed cerebellar haematoma and a fourth with focal demyelinating disease. Ocular oscillations were conjugate, horizontal, symmetrical, occurred in bursts of several seconds duration, had amplitudes of 30 degrees to 50 degrees, and were evoked whenever the patient attempted to shift visual fixation or pursue a moving target. Photo-electric recordings in one patient with tumour defined features of this disorder of saccadic eye movement: (i) oscillation was composed of saccades, (ii) frequency was 2 Hz, (iii) bursts occurred with amplitude first increasing and then decreasing, (iv) intervals between beginnings of saccades averaged 260 ms and (v) eye position did not exhibit systematic drift during the intersaccadic period. These features documented the inreased gain and instability of the visually guided saccadic system. By using increased feed-forward gain in a sampled-data control model we simulated the pattern of macrosaccadic oscillation. We belive that the acute loss of the calibrator function of the cerebellum accounts for the gain abnormality underlying macrosaccadic oscillation.- - - - - - - - - - ranking = 1keywords = horizontal (Clic here for more details about this article) |
2/36. Acquired convergence-evoked pendular nystagmus in multiple sclerosis.Nystagmus seen only with convergence is unusual. We describe four cases of acquired convergence-evoked pendular nystagmus in patients with multiple sclerosis. The nystagmus was horizontal and asymmetric in all patients. Eye movement recordings in one subject showed a conjugate rather than a convergent-divergent relationship of the phase of movement between the two eyes. All patients had evidence of optic neuropathy and cerebellar dysfunction. Occlusion of either eye during fixation of near targets led to divergent drift of the covered eye and a decrease in nystagmus. Intravenous scopolamine reduced nystagmus in one patient. Base-in prisms alleviated symptoms of oscillopsia at near and improving reading visual acuity. Convergence-evoked pendular nystagmus may be more common than currently appreciated, particularly among patients with multiple sclerosis.- - - - - - - - - - ranking = 22021.296361639keywords = pendular nystagmus, nystagmus, pendular, horizontal (Clic here for more details about this article) |
3/36. Complete bilateral horizontal gaze paralysis disclosing multiple sclerosis.Two women presented with bilateral internuclear ophthalmoplegia evolving in a few days to complete bilateral horizontal gaze paralysis. Convergence and vertical eye movements were normal. Cerebral MRI showed a few small white matter lesions in the lateral ventricle regions, and, at the brainstem level, a single, small, bilateral lesion affecting the posterior part of the medial pontine tegmentum and responsible for the clinical syndrome. The condition gradually improved in both patients, following a similar progression as at the onset: improvement first involved the adduction movements in both eyes, whereas bilateral abduction paresis still persisted for a few weeks, before complete recovery of eye movements. Bilateral damage to the medial longitudinal fasciculus and subsequent lateral extent of damage to the region of the two abducens emerging fibres may explain the clinical findings. In both cases, the cause was probably multiple sclerosis.- - - - - - - - - - ranking = 5.0582027458775keywords = horizontal, vertical (Clic here for more details about this article) |
4/36. Ocular contrapulsion in multiple sclerosis: clinical features and pathophysiological mechanisms.The objective was to describe in multiple sclerosis, a cerebellar eye movement syndrome that resulted from an acute episode of inflammatory demyelination. Contrapulsion is an ocular motor disturbance characterised by a triad of (1) hypermetric saccadic eye movements in a direction opposite from a precisely localised lesion within a specific white matter pathway, the uncinate fasciculus, at the level of the superior cerebellar peduncle (SCP); (2) hypometric saccades towards the side of the lesion; (3) oblique saccades directed away from the side of the lesion on attempted vertical saccades. Infrared oculography was used to demonstrate the characteristic features of contrapulsion in two patients with multiple sclerosis. brain MRI showed lesions within the region of the uncinate fasciculus and superior cerebellar peduncle in both patients. Eye movement recordings showed saccadic hypermetria away from the side of the lesion and saccadic hypometria towards the side of the lesion. The hypometria decomposed into a series of stepwise movements as the eye approached the target. Oblique saccades directed away from the side of the lesion were seen on attempted vertical saccades.In conclusion, ocular contrapulsion can be seen in patients with multiple sclerosis and results from a lesion in the region of the SCP, involving the uncinate fasciculus.- - - - - - - - - - ranking = 0.116405491755keywords = vertical (Clic here for more details about this article) |
5/36. A pilot study of gabapentin as treatment for acquired nystagmus.The effects of the anticonvulsant gabapentin were measured on vision and eve movements in three patients with acquired pendular nystagmus. In two patients, the nystagmus was associated with multiple sclerosis and, in the other, it followed brainstem stroke. A single oral 600 mg dose of gabapentin produced improvement of vision due to changes in ocular oscillations in all three patients. The effect was sustained after five weeks of treatment in two patients who elected to continue taking gabapentin 900-1500 mg/day. The results of this pilot study suggest that a controlled trial of gabapentin should be conducted to evaluate its role in the treatment of acquired forms of nystagmus.- - - - - - - - - - ranking = 6387.5533630642keywords = pendular nystagmus, nystagmus, pendular (Clic here for more details about this article) |
6/36. Perverted head-shaking nystagmus: a possible mechanism.The authors describe a patient with acute MS who developed vertigo (tumbling) and downbeat nystagmus upon horizontal head oscillation (perverted head-shaking nystagmus). The only abnormality on brain MRI was a hyperintense signal in the caudal medulla that contains the nucleus Roller and nucleus intercalatus. These nuclei project to structures involved in the velocity storage system for horizontal vestibulocular reflex (VOR) and vertical VOR, and also to the vestibular cerebellum. The authors offer possible mechanisms for perverted nystagmus in this patient.- - - - - - - - - - ranking = 3460.6996184193keywords = nystagmus, horizontal, vertical (Clic here for more details about this article) |
7/36. Divergence insufficiency and demyelinating disorder.PURPOSE: To describe a divergence insufficiency in a young woman. methods: Case report. RESULTS: A 38-year-old woman presented with a episode of homonymus horizontal diplopia at distance. She was orthophoric at near but had esotropia at distance. Neurological evaluation was normal but multiple demyelinating lesions were shown in the magnetic resonance scan, with increased intrathecal Ig G production. Double vision improved after corticosteroid mega-doses. CONCLUSIONS: An acute onset of diplopia due to divergence insufficiency in a young adult may be associated with a demyelinating disorder.- - - - - - - - - - ranking = 1keywords = horizontal (Clic here for more details about this article) |
8/36. Combined pharmacologic and surgical approach to acquired nystagmus due to multiple sclerosis.PURPOSE: To describe a combined pharmacological and surgical approach to treating acquired nystagmus in a patient with multiple sclerosis. DESIGN: Interventional case report. methods: A 40-year-old patient with acquired horizontal and vertical nystagmus and severe oscillopsia secondary to multiple sclerosis had combined treatment with gabapentin and a vertical Kestenbaum-type procedure. RESULTS: After gabapentin treatment (3,000 mg orally daily) the horizontal nystagmus was significantly reduced, and the patient developed a marked chin-up position. The vertical nystagmus remained unchanged, dampening on downgaze. A recession of both inferior rectus muscles reduced the nystagmus significantly in primary position, the abnormal head position disappeared, and oscillopsia completely resolved. Treatment increased visual acuity from 6/24 in the right eye and 6/60 in the left eye to 6/9 in both eyes. CONCLUSIONS: Acquired nystagmus in multiple sclerosis can be significantly improved by using a combined pharmacological and surgical approach.- - - - - - - - - - ranking = 4943.0909163425keywords = nystagmus, horizontal, vertical (Clic here for more details about this article) |
9/36. Improvement of acquired pendular nystagmus by gabapentin: case report.Acquired Pendular Nystagmus (APN) may cause distressing visual symptoms in patients who are already suffering a severe general disease. Averbuch-Heller et al. conducted the first double-blind controlled study on treatment for APN. They showed that gabapentin substantially reduces pendular nystagmus and significantly increases visual acuity in the majority of patients. We present a patient with APN due to multiple sclerosis who suffered severe oscillopsy and reduction of visual acuity and who substantially benefited from a trial treatment with this agent.- - - - - - - - - - ranking = 17115.017891006keywords = pendular nystagmus, nystagmus, pendular (Clic here for more details about this article) |
10/36. Familial multiple sclerosis: case study of three affected siblings.We report on three sisters with new-onset multiple sclerosis (MS). The symptoms of the eldest sister began in 1993 with lower-limb weakness and paraesthesia. In 1998, she had limb weakness, nystagmus and ataxia. magnetic resonance imaging (MRI) of the brain, the cerebrospinal fluid (CSF) examinations, and evoked potentials verified MS. The middle sister exhibited left-side optic neuritis in 1998. All findings pointed to MS. The third sister had subjective complaints such as paraesthesias and vertigo. MRI and CSF results supported the diagnosis. Both parents and all four grandparents are without neurological signs; the brain MRI examinations on the parents were negative. The prevalence of familial MS in first-degree relatives is 5-10%, while that in twins is 20-30%. In this case, environmental factors seem to play the crucial role. Although the anamnesis as concerns MS proved negative in the other family members examined here, further genetic examination of the sisters is needed.- - - - - - - - - - ranking = 494.09163081049keywords = nystagmus (Clic here for more details about this article) |
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