1/78. 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 = ocular (Clic here for more details about this article) |
2/78. Immunoadsorption--a new therapeutic possibility for multiple sclerosis?A 46 year old woman suffers from chronic progressive multiple sclerosis. She was diagnosed in 1993. Because of many complications seen in conservative treatment, plasma exchange was started. The expanded disability status scale by Kurtzke could be improved but the interval between the treatments became shorter and shorter. It was therefore decided to commence protein A immunoadsorption treatment. With this treatment the patient shows good and stable improvement in neurological and functional status with an acceptable treatment frequency of once every 3 weeks.- - - - - - - - - - ranking = 751.69759334421keywords = chronic progressive (Clic here for more details about this article) |
3/78. Ankylosing spondylitis and multiple sclerosis.Ankylosing spondylitis can be associated with extra-articular involvement. Besides internal and ocular complications, neurological manifestations such as single root lesions, compression of the myelum or the cauda equina syndrome have also been described. We present a patient with ankylosing spondylitis who developed a monophasic myelopathy resembling multiple sclerosis. literature data show no conclusive evidence for an increased association of ankylosing spondylitis and multiple sclerosis. However, a monophasic myelopathy may be a separate neurological manifestation associated with ankylosing spondylitis.- - - - - - - - - - ranking = 0.2keywords = ocular (Clic here for more details about this article) |
4/78. Impairment of depth perception in multiple sclerosis is improved by treatment with AC pulsed electromagnetic fields.multiple sclerosis (MS) is associated with postural instability and an increased risk of falling which is facilitated by a variety of factors including diminished visual acuity, diplopia, ataxia, apraxia of gait, and peripheral neuropathy. Deficient binocular depth perception may also contribute to a higher incidence of postural instability and falling in these patients who, for example, find it an extremely difficult task to walk on uneven ground, over curbs, or up and down steps. I report a 51 year old woman with secondary progressive MS who experienced difficulties with binocular depth perception resulting in frequent falls and injuries. Deficient depth perception was demonstrated also on spontaneous drawing of a cube. Following a series of transcranial treatments with AC pulsed electromagnetic fields (EMFs) of 7,5 picotesla flux density, the patient experienced a major improvement in depth perception which was evident particularly on ascending and descending stairs. These clinical changes were associated with an improvement in spatial organization and depth perception on drawing a cube. These findings suggest that in MS impairment of depth perception, which is encoded in the primary visual cortex (area 17) and visual association cortex (areas 18 and 19), may be improved by administration of AC pulsed EMFs of picotesla flux density. The primary visual cortex is densely innervated by serotonergic neurons which modulate visual information processing. Cerebral serotonin concentrations are diminished in MS patients and at least some aspects of deficient depth perception in MS may be related to dysfunction of serotonergic transmission in the primary visual cortex. It is suggested that transcranial AC pulsed applications of EMFs improve depth perception partly by augmenting serotonergic transmission in the visual cortex.- - - - - - - - - - ranking = 0.4keywords = ocular (Clic here for more details about this article) |
5/78. A common mechanism for the control of eye and head movements in humans.How the human brain controls the subtle coupling between eye and head movements is still debated. The brain could either coordinate two separate (eye and head) networks or use a single system involved in gaze (eye head) control. In a recent report, a total transfer from eye to head movements was observed in a patient with congenital ophthalmoplegia. This led the authors to hypothesize that such transfer resulted from a long-term adaptation between oculomotor and head movement systems. We report on a patient in whom a similar transfer was observed but at the acute stage of an acquired ophthalmoplegia. This case demonstrates that the transfer between head and eye movements does not necessarily require long-term adaptation and supports the hypothesis of a common unique gaze motor command in which eye and head movements would be rapidly exchangeable.- - - - - - - - - - ranking = 4.2823613692779keywords = ophthalmoplegia (Clic here for more details about this article) |
6/78. 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 = 2.1411806846389keywords = ophthalmoplegia (Clic here for more details about this article) |
7/78. 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 = 0.4keywords = ocular (Clic here for more details about this article) |
8/78. Postoperative inflammation in a patient with multiple sclerosis.We report a 51-year old white woman with a history of relapsing episodes of multiple sclerosis (MS) who developed acute anterior uveitis 11 days after having uneventful phacoemulsification with posterior chamber intraocular lens implantation. Topical corticosteroids relieved the pain and inflammation within hours. A week after the episode of anterior uveitis, the patient had a severe systemic relapse of MS. Acute inflammation in MS patients during the postoperative period may be noninfectious and could be a prodrome for a relapse of MS.- - - - - - - - - - ranking = 0.2keywords = ocular (Clic here for more details about this article) |
9/78. 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 = 0.2keywords = ocular (Clic here for more details about this article) |
10/78. 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 = 0.2keywords = ocular (Clic here for more details about this article) |
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