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)

Blepharospasm, the most frequent feature of cranial dystonia, and hemifacial spasm are two involuntary movement disorders that affect facial muscles. The cause of blepharospasm and other forms of cranial dystonia is not known. Hemifacial spasm is usually due to compression of the seventh cranial nerve at its exit from the brain stem. Cranial dystonia may result in severe disability. Hemifacial spasm tends to be much less disabling but may cause considerable distress and embarrassment. Patients affected with these disorders are often mistakenly considered to have psychiatric problems. Although the two disorders are quite distinct pathophysiologically, therapy with botulinum toxin has proven very effective in both. We review the clinical features, proposed pathophysiologic features, differential diagnosis and treatment, including the use of botulinum toxin, of cranial dystonia and hemifacial spasm.
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PMID:Cranial dystonia, blepharospasm and hemifacial spasm: clinical features and treatment, including the use of botulinum toxin. 305 71

We have studied the orbicularis oculi reflex to paired stimuli in patients with various forms of focal dystonia and in normal controls. In normals, the conditioning stimulus (CS) facilitated the test stimulus (TS) early response (R1), but markedly inhibited the TS polysynaptic late response (R2). In all types of dystonias studied the CS facilitated the TSR1 as in normals. However, in patients with blepharospasm (alone or associated with oromandibular dystonia), spasmodic torticollis, or spasmodic dysphonia, it inhibited the TSR2 significantly less than that of the controls, with marked enhancement of the recovery curve of the late response. The TSR2 recovery curve of patients with focal arm dystonia was normal. These results are indicative of increased brainstem interneuron excitability in the various dystonias mediated by the cranial nerves, but not in focal arm dystonias such as dystonic writer's cramp. This abnormality might be caused by an abnormal input possibly from the basal ganglia upon these brainstem cells. Our results also suggest that a similar pathophysiology underlies the various focal dystonias of the head and neck.
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PMID:Blink reflex studies in focal dystonias: enhanced excitability of brainstem interneurons in cranial dystonia and spasmodic torticollis. 1139 67

Secondary dystonias and experimental models of dystonia suggest that mechanisms responsible for primary dystonias may lie in the basal ganglia or brainstem. A histological study has been done in three patients with cranial dystonia (blepharospasm with oromandibular dystonia in two, blepharospasm alone in one), and one patient with craniocervical dystonia (oromandibular dystonia with retrocollis). In the patient with blepharospasm alone, an angioma, 0.5 mm in diameter, was found in the dorsal pons at the site of the central tegmental tract, confirming that some patients presenting with primary dystonias may have longstanding lesions in the brainstem. In the three other cases, the striatum, pallidum, thalamus, and brainstem were examined and cell populations in the putamen, substantia nigra, and inferior olives were compared with age-matched controls, but no significant abnormality was found.
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PMID:Pathological report of four patients presenting with cranial dystonias. 319 61

Four patients with severe Meige's disease (blepharospasm-oromandibular dystonia) have been treated, after having given an informed consent, by local injections of purified botulinum toxin type "A". Previous systemic therapy with anticholinergics, dopamine antagonists and other drugs had been unsuccessful in all these subjects. Each patient was treated by saline solution injected with the same method as botulinum toxin, just once. The self-evaluation of patients and the clinical evaluation that some of us- unaware of the kind of therapy which had been performed- gave to the symptoms on the basis of videotapes, for each session of injection, showed that the injections of botulinum toxin are effective in the treatment of such disorder. The duration of the beneficial effect was slightly shorter in these patients than in patients with blepharospasm treated by the same method.
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PMID:Use of botulinum toxin in Meige's disease. 324 65

The epidemiology of generalized and focal dystonias was investigated in the Rochester, Minnesota, population over the period 1950-1982. The crude incidence of generalized dystonia was 2 per million persons per year, and for all focal dystonias combined, 24 per million per year. The crude prevalence rate was 34 per million persons for generalized dystonia and 295 per million persons for all focal dystonias. Torticollis was the most common focal dystonia; essential blepharospasm, oromandibular dystonia, spasmodic dysphonia, and writer's cramp were less common and had roughly equal incidence and prevalence rates.
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PMID:Epidemiology of focal and generalized dystonia in Rochester, Minnesota. 326 51

Meige's syndrome is a form of cranial dystonia characterized by the presence of bilateral dystonic spasms of the facial muscles and frequently of other cranial muscles as well. Its most common and disabling manifestation is blepharospasm which can render the patient functionally blind. Several types of orbicularis oculi spasms occur in Meige's syndrome: brief clonic spasms, prolonged dystonic spasms, constant tonic contraction, and "apraxia" of lid opening. In the completed form of the syndrome, blepharospasm is typically associated with lower facial or oromandibular dystonia. Spasms of the neck and limb muscles, generally mild, and action tremor not uncommonly accompany the cranial dystonia. In most patients the cause of the spasms is unknown. This so-called idiopathic or primary form of Meige's syndrome is considered an adult form of adult onset dystonia. Secondary Meige's syndrome can be encountered in the context of several neurodegenerative disorders, chronic administration of neuroleptics, levodopa, or other drugs, and in patients with focal brain lesions. These secondary cases of Meige's syndrome suggest that a dysfunction of the basal ganglia or of the mesencephalic/diencephalic region plays an important role in the pathophysiology of this dystonic syndrome. Recent neurophysiologic studies and postmortem findings in some patients also support the notion that disease of the brain stem contributes to the pathophysiology of orofacial dystonia.
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PMID:Blepharospasm-oromandibular dystonia syndrome (Meige's syndrome): clinical aspects. 327 55

Objective quantification of the symptoms of Meige's syndrome is difficult and has not been performed in the majority of pharmacological studies of Meige's syndrome published so far. The aim of the present study was to reexamine the therapeutic potential of biperiden, clonazepam, haloperidol, and lisuride using an objective method of quantification of the symptoms. Eleven patients received daily i.v. injections of biperiden, 5.0 mg; clonazepam, 1.0 mg; haloperidol, 2.5 mg; lisuride, 0.05 mg; and placebo in randomized order. The symptoms of the patients [idiopathic blepharospasm (IB), in 11 patients, oromandibular dystonia (OMD) in four patients] were quantified by a blind observer counting the frequencies and recording the cumulative duration of sustained spasms of IB and OMD over periods of 4 min before, and 15, 30, 60, 90, and 120 min after the i.v. challenges. Baseline quantification of IB and OMD was performed at identical intervals on randomized days of the trial. Significant improvement of the IB scores was found in response to biperiden and clonazepam and a trend toward improvement in response to lisuride (Wilcoxon test). Evaluation of the individual IB scores of each patient following the various drug challenges failed to predict the therapeutic potential of these drugs for subsequent oral treatment.
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PMID:Pharmacological study in Meige's syndrome with predominant blepharospasm. 328 Jan 28

Dystonia is mysterious and its pathophysiology is uncertain. The fundamental motor abnormality is an abnormality of muscle command signals, such that the wrong agonists may be activated for too long, there is abnormal co-contraction of agonist and antagonists, and there is excessive and misdirected action of synergists and postural fixators. The result is action dystonia. In addition, muscle spasms may occur spontaneously. The peripheral motor apparatus, the corticomotoneurone pathway, and (as far as is known) the proprioceptive feedback machinery, are all intact in primary dystonia. However, a defect of interneuronal machinery has been identified in both the brainstem and spinal cord. In blepharospasm there is hyperexcitability of the lower brainstem interneurones responsible for the R2 component of the blink reflex. In the dystonic arm there is loss of the later phases of Ia reciprocal inhibition from extensors to flexors. Both deficits may be due to loss of normal basal ganglia inputs onto interneurones. The known sites of focal lesions that may cause symptomatic dystonia all impair basal ganglia output. However, whether such abnormal interneuronal function is sufficient to explain dystonia is not known. Among many unanswered questions are 1) are the cortical instructions for movement specified correctly, and 2) what is responsible for the spontaneous dystonic spasms?
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PMID:The physiology of idiopathic dystonia. 331 55

Meige's disease is a distressing complaint, the treatment of which often poses a challenge to the neurologist. The patient described here had blepharospasm-oromandibular dystonia, which responded transiently to oral lisuride. On three occasions, drug holidays successfully restored efficacy but thereafter further trials proved fruitless. Continuous subcutaneous lisuride administration in 0.35 mg doses per day, by means of a portable infusion pump, led to sustained improvement for 7 months. No major side effects were observed. Our findings suggest that this treatment deserves further trials.
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PMID:Continuous dopaminergic stimulation in cranial dystonia. 340 58

The natural history and response to different treatments have been evaluated in 264 patients with blepharospasm. The mean age of onset was 55.8 years and there was a female preponderance of 1.8 to 1. Dystonia elsewhere was found in 78% of patients, usually in the cranial-cervical region, and appeared to follow a somatotopic progression. A family history of blepharospasm or dystonia elsewhere was found in 9.5% of cases, which suggests a genetic predisposition. Ocular lesions preceded the onset of blepharospasm in 12.1% of cases. The response to drugs was inconsistent, although initial improvement was experienced by one fifth of patients treated with anticholinergics. Twenty-nine bilateral facial nerve avulsion operations were performed with benefit in 27 cases; but recurrences appeared in 22, on average one year after surgery. Botulinum toxin injections were performed in 151 patients. Significant improvement was achieved in 118 cases. Mean duration of benefit was 9.2 weeks. Transient ptosis and diplopia were the commonest side effects.
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PMID:Blepharospasm: a review of 264 patients. 340 84


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