1/22. Adverse effect of dopamine agonist therapy in a patient with motor-intentional neglect.Studies in animals and humans report dopamine agonists can improve neglect. Because dopamine deficit reduces intention to act, it has been suspected the dopamine agonist bromocriptine would improve deficient hemispatial intention. Thus, the effect of bromocriptine on line bisection was examined in a patient with neglect and failure of the action-intention system. The 58-year-old patient had left-sided neglect from a right cerebral infarction involving both cortical and subcortical (striatal) structures. It was determined that neglect on a line bisection task was attributable to a motor-intentional bias by testing under congruous and incongruous video monitoring. Testing sessions were held before starting bromocriptine, on 20 mg/d, and after stopping bromocriptine. The patient's ipsilesional bias increased on bromocriptine, and improved when bromocriptine was stopped. bromocriptine may worsen neglect if putamenal receptors are damaged. dopamine agonists may activate the normal hemisphere, increasing an intentional bias. Clinicians using dopaminergic pharmacotherapy should assess patients for this possible adverse effect.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
2/22. Cerebral arteriovenous malformations and movement disorders.A series of six patients with movement disorders associated with cerebral arteriovenous malformations (AVM) is reported. The AVMs were classified according to the Spetzler-Martin classification as grade V (one patient), grade IV (four patients), and as grade III (one patient). One patient had action-induced hemidystonia caused by a contralateral frontoparietal AVM which compressed the putamen and was supplied partially by enlarged lenticulostriate arteries. Two patients presented with unilateral cortical tremor associated with contralateral high-frontal cortical/subcortical AVMs sparing the basal ganglia. Another patient developed hemidystonia and hemichorea-hemiballism after bleeding of a contralateral temporooccipital AVM and subsequent ischemia. Two patients had focal dystonia after thalamic and basal ganglia hemorrhage from AVMs. Five patients were operated on. The movement disorder was abolished in one patient postoperatively. Different mechanisms were identified that are relevant for the development of AVM-related movement disorders: mass effect, diaschisis, local parenchymal altered cerebral blood flow, and hemorrhagic or ischemic structural lesions.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
3/22. Delayed encephalopathy after strangling.An 11-year-old boy who had been the victim of a strangling attempt was asymptomatic for one week whereupon involuntary movements involving the trunk and limbs developed, along with repetitive episodes of opisthotonos and autonomic dysfunction. Meanwhile, he remained alert and appeared to be mentally intact. An electroencephalogram was normal. He died 13 weeks after the onset of the neurological disorder. The neuropathological examination showed cavitating lesions in the caudate nucleus, putamen, and globus pallidus bilaterally, with sparing of the white matter. The delayed onset of a progressively evolving neurological disorder has been noted in various forms of hypoxicischemic insult, including previously reported cases of strangling, but its occurrence cannot be predicted from the preceding clinical state or course. In the cases in which abnormal movements have been predominant, the pathological findings have been similar despite diversity in the preceding circumstances. We suggest the underlying metabolic disorder common to these cases may be lactic acidosis, and that they should be studied for evidence of a biochemical defect.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
4/22. Unilateral asterixis.We describe three patients with unilateral asterixis. One diabetic patient with a moderately-sized haematoma in the left putamen initially developed bilateral and symmetrical asterixis, which became confined to the right side as his diabetes mellitus was controlled. Two patients showed unilateral asterixis due to haematomas in the contralateral basal ganglia and thalamus, respectively. The present findings indicate that not only lesions of the thalamus but also those of the basal ganglia can cause unilateral asterixis, and bilateral and symmetrical asterixis does not necessarily exclude the presence of a focal mass lesion in the cerebrum.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
5/22. Hypoxic-ischemic damage of the basal ganglia. case reports and a review of the literature.Three cases of movement disorders secondary to hypoxic-ischemic encephalopathy are reported. Despite similarities among the clinical events, the neurological syndromes produced were dissimilar. Cerebral hypoxia-ischemia typically produces lesions of the globus pallidus that may result in an akinetic rigid syndrome. Due to its unique blood supply, vascular insufficiency is found to be a major factor. Lesions in the putamen also occur, and these tend to be associated with dystonia. Recent evidence supports a specific neuronal sensitivity in the striatum, possibly due to afferent excitatory amino acid connections. These two components and changes in the levels of neurotransmitters during hypoxia-ischemia may interact to produce varied clinical outcomes. These factors must also be considered when planning therapeutic interventions.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
6/22. Spontaneous hemiballism and disappearance of parksinsonism following contralateral lenticular lacunar infarct.Hemiballism was observed in a 77-year-old woman with Parksinson disease after a contralateral lenticular infarct without apparent involvement of the subthalamic nucleus. Parkinsonian signs ipsilateral to the hemiballism remained abolished despite subsequent nearly complete recovery from the hyperkinesias. It is argued that clinical events were due to a single ischemic lesion of the putamen-pallidum complex.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
7/22. Regional brain glucose metabolism in neuroacanthocytosis.Two brothers with neuroacanthocytosis had [18F]-2-fluoro-2-deoxyglucose PET scans showing marked glucose hypometabolism of the caudate and putamen. MRIs showed no evidence of atrophy or modification of signal intensity in these structures. Decreased glucose utilization of the striatum can underlie hyperkinetic movement disorders of various etiologies.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
8/22. Hemiballismus: study of a case using positron emission tomography with 18fluoro-2-deoxyglucose.A 64-year-old man had right-sided persistent hemiballismus. Cerebral computed tomography (CT) and 0.5-T magnetic resonance imaging (MRI) showed no abnormalities, but 1.5-T MRI showed decreased signal intensity of the putamina, greater on the left than on the right. The subthalamic area was normal on CT and MRI. Positron emission tomography with 18fluoro2-deoxyglucose showed marked hypometabolism of the left putamen (60% of the right) and hypermetabolism of the left parietal lobe (138% of the right). The decreased metabolism of the left putamen may indicate a reduction in neuronal firing. The pathophysiology of the hemiballismus in this case may be loss of tonic inhibition of the lateral globus pallidus from the putamen, leading in turn to greater inhibition of the subthalamic nucleus, less excitation of the medial globus pallidus, and less inhibition of the thalamus and motor cortex, and thus allowing expression of the ballistic movements.- - - - - - - - - - ranking = 3keywords = putamen (Clic here for more details about this article) |
9/22. Positron emission tomographic study of D2 dopamine receptor binding and CSF biogenic amine metabolites in rett syndrome.We report on the first positron emission tomographic study of dopamine receptor binding in rett syndrome. The patient is a 25 year old Austrian woman diagnosed at age 2 and followed since then by Rett. A computed axial tomogram (CT scan) showed cortical atrophy, and enlarged ventricles but normal structure of the caudate/putamen. Following the CT scan 20 mCi of 11 C N-methyl spiperone, a butyrophenone with a high affinity for dopamine D2 receptors was administered intravenously. The patient was found to have dopamine D2 receptor binding activity in the low normal range. The caudate/cerebellar activity ratio was below the mean regression line (p = 0.10) that relates the CA/CB ratio as a function of age. Levels of cerebrospinal fluid neurotransmitter metabolites were normal.- - - - - - - - - - ranking = 1keywords = putamen (Clic here for more details about this article) |
10/22. Preliminary brain autopsy findings in progredient rett syndrome.Postmortem human brain analyses have been performed to further evaluate pathogenetic aspects of the rett syndrome. While there are no significant abnormalities with respect to amino acid concentrations in putamen, caudate nucleus, red nucleus and thalamus, the concentration of kynurenine is increased in putamen, caudate nucleus, gl. pallidus, raphe and amygdaloid n. In contrast, serotonin and its metabolite 5-hydroxyindole acetic acid are below normal levels. D2-receptor number is decreased and there is a significant drop in the concentration of the iron-binding protein ferritin. It can be concluded, that reduction of D2-receptors is due to loss of cholinergic and GABA-ergic cell bodies in the striatum or may be a response to iron deficiency. Low serotonergic and high kynurenergic activity may be of pathogenetic importance in the frequently observed cerebral seizures in rett syndrome.- - - - - - - - - - ranking = 2keywords = putamen (Clic here for more details about this article) |
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