Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances--principally iron--that delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in signal secondary to the T2* effect. Movement disorders are associated with either increased or decreased signal or both in these structures, depending on the pathologic process. In the initial evaluation of 113 patients with a variety of movement disorders, good correlation of imaging abnormalities can be made with a simplified schema of the extrapyramidal pathways and a system of classification of abnormal movements, parkinsonism/tremor, dystonia, chorea, myoclonus, and hemiballismus. Parkinsonisms are characterized by abnormalities of the cortico-ponto-cerebello-dentato-rubro-thalamo-cortico-spinal tract or the nigrostriatal tract. Dystonias are characterized by abnormalities of the neostriatum predominantly affecting the putamen. Choreas are also characterized by abnormalities of the neostriatum but predominantly affecting the caudate nucleus. Hemiballismus is characterized by lesions affecting the subthalamic nucleus or associated pathway.
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PMID:Study of movement disorders and brain iron by MR. 244 Feb 91

Chronic electrical subthalamic nucleus (STN) stimulation is under investigation for alleviating parkinsonian symptoms. STN alterations may carry the risk of provoking abnormal involuntary movements (AIMs). We took advantage of the reversibility of the stimulation technique to assess the possibility of inducing AIMs, using different electrical variables with or without concomitant levodopa intake. Above a given threshold voltage, stimulation could induce contralateral distal mobile AIMs or hemiballism in the off-drug condition in two patients. AIMs occurred after a latency that varied from a few minutes up to several hours after switching on the stimulator. Hemiballism immediately disappeared upon switching off the stimulator. In these patients, levodopa had never provoked that type of AIMs before surgery. Levodopa-induced AIMs were not modified by electrical stimulation, but off-phase dystonia disappeared in one patient. Stimulation of the STN induced AIMs that resembled both those observed following spontaneous lesions of the STN and levodopa-induced diphasic AIMs in parkinsonian patients. As electrical stimulation provoked AIMs and antiparkinsonian benefit occurred with different electrical variables and different timing, the mechanisms responsible for these two effects could be distinct.
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PMID:Abnormal involuntary movements induced by subthalamic nucleus stimulation in parkinsonian patients. 872 37

The symptomatic and functional outcomes of a series of 14 patients with disabling and medically refractory hemiballism who were treated with functional stereotactic surgery are reported. Seven (50%) of the 14 patients had concomitant hemichorea. To relieve the hyperkinesia, the 14 patients underwent a total of 15 stereotactic operations (one patient had a second stereotactic procedure). Combined lesions in the contralateral zona incerta and the base of the ventrolateral (oroventral) thalamus were applied in 13 instances. The zona incerta was reached by means of a movable chord electrode to obviate the need for repeated puncture. In two instances the medial pallidum was used as the stereotactic target. Hemiballism was abolished or considerably improved in 13 (93%) of 14 patients in the immediate postoperative phase. Residual dyskinesia was evaluated using the hemiballism/hemichorea outcome rating scale. Long-term follow-up review was available for 13 of the 14 patients (mean follow-up period 11 years). Persistent improvement in the hemiballism was found in 12 of these 13 patients: seven patients (54%) were free of any hyperkinesia and five patients (39%) had minor residual and predominantly hemichoreic hyperkinesia. One of the 13 patients presented with a probable psychogenic movement disorder at long-term follow-up examination. Persistent morbidity, most likely related to the operative intervention, was detected in three of the 13 patients; this included mild hemiparesis and dystonia. Functional disability was assessed using the Huntington's Disease Activities of Daily Living scale. The patients' preoperative mean value of 83% of maximum disability was reduced to a mean of 30% observed at long-term follow-up review (p < 0.001). The residual disability exhibited in most older patients was associated with cardiovascular disease. The authors compare their findings with the results of 44 cases reported previously. The authors contend that functional stereotactic surgery should be considered in patients with persistent, medically refractory hemiballism.
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PMID:Functional stereotactic surgery for hemiballism. 875 57

Clinically relevant movement disorders are identified in 3% of patients with HIV infection seen at tertiary referral centres. In the same setting, prospective follow-up shows that 50% of patients with AIDS develop tremor, parkinsonism or other extrapyramidal features. Hemiballism-hemichorea and tremor are the most common hyperkinesias seen in patients who are HIV positive, but other movement disorders diagnosed in these patients include dystonia, chorea, myoclonus, tics, paroxysmal dyskinesias and parkinsonism. Patients with movement disorders usually present with other clinical features such as peripheral neuropathy, seizures, myelopathy and dementia. In the vast majority of patients, hyperkinesias result from lesions caused by opportunistic infections, particularly toxoplasmosis, which damage the basal ganglia connections. On the other hand, parkinsonism and tremor can result from dopaminergic dysfunction resulting from HIV itself or the use of antidopaminergic drugs. The management of patients who are HIV positive who present with movement disorders involves recognition and treatment of opportunistic infections, symptomatic treatment of the movement disorder and the use of highly active antiretroviral therapy (HAART). The most effective treatment of cerebral toxoplasmosis in patients with HIV infection is the combination of sulfadiazine and pyrimethamine. Symptomatic treatment of the movement disorder is often disappointing: hemiballism improves with antipsychotics, but tremor, parkinsonism and other phenomena usually fail to respond to available therapies. Preliminary data suggest that HAART may be helpful in the symptomatic control as well as prevention of movement disorders in patients who are HIV positive.
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PMID:HIV-related movement disorders: epidemiology, pathogenesis and management. 1226 60

Hypocalcaemia is an established cause of neurological and psychiatric disease with numerous clinical manifestations. The aim of the study was to determine the outcome of severe neuropsychiatric manifestations of chronic hypocalcaemia after correction of calcium levels. Clinical and laboratory data of 22 patients seen between 1999 and 2009 were retrospectively analysed. Calcium, magnesium, phosphorus, albumin and parathormone values were measured in all cases. All patients except infants under one year of age had computed tomography (CT) scans of the head. Most patients (n = 19; 86%) presented with generalised tonic clonic convulsions while three had seizures with psychiatric manifestations. Movement disorders were present in 4 patients and one had candida meningitis. Nineteen of the 22 patients had primary hypoparathyroidism of which one had associated mucocutaneous candidiasis. One had pseudohypoparathyroidism and two had vitamin D deficiency. All patients improved with calcitriol and calcium treatment. Twelve of the 14 patients with convulsions could be taken off anticonvulsants. Hemiballismus disappeared in one patient and choreiform movements disappeared in one patient and dystonia in two patients. Psychiatric manifestations improved but did not disappear in the three patients who had them. Adult patients with seizures or neuropsychiatric manifestations should have calcium levels checked. Seizure disorders due to chronic hypocalcaemia had excellent prognosis on correction of serum calcium levels. Movement disorders improved markedly. Psychiatric manifestations did not improve substantially on correction of serum calcium levels.
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PMID:Neuropsychiatric manifestations and their outcomes in chronic hypocalcaemia. 2459 58