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)

The effect of chronic bilateral high-frequency stimulation of the subthalamic nucleus (STN) on levodopa-induced dyskinaesias was investigated in eight patients with fluctuating Parkinson's disease complicated by functionally disabling off-period dystonia. All of the patients also had severe diphasic and peak-dose chorea, so that it was possible to study the effect of high-frequency stimulation on the different types of levodopa-induced dyskinaesias. Off-period fixed dystonia was reduced by 90% and off-period pain by 66%. After acute levodopa challenge, high-frequency stimulation of the STN reduced diphasic mobile dystonia by 50% and peak-dose choreic dyskinaesias by 30%. The effect of bilateral high-frequency stimulation of the STN on the Unified Parkinson's Disease Rating Scale motor score had the same magnitude as the preoperative effect of levodopa. This allowed the levodopa dose to be reduced by 47%. The combination of reduced medication and continuous high-frequency stimulation of the STN reduced the duration of on-period diphasic and peak-dose dyskinaesias by 52% and the intensity by 68%. Acute high-frequency stimulation of the STN mimics an acute levodopa challenge, concerning both parkinsonism and dyskinaesias, and suppresses off-period dystonia. Increasing the voltage can induce repetitive dystonic dyskinaesias, mimicking diphasic levodopa-induced dyskinaesias. A further increase in voltage leads to a shift from a diphasic-pattern dystonia to a peak-dose pattern choreodystonia. Chronic high-frequency stimulation of the STN also mimics the benefit of levodopa on parkinsonism and improves all kinds of levodopa-induced dyskinaesias to varying degrees. Off-period dystonia, associated with neuronal hyperactivity in the STN is directly affected by stimulation and disappears immediately. The effect of chronic high-frequency stimulation of the STN on diphasic and peak-dose dyskinaesias is more complex and is related directly to the functional inhibition of the STN and indirectly to the replacement of the pulsatile dopaminergic stimulation by continuous functional inhibition of the STN. Chronic high-frequency stimulation of the STN allows a very gradual increase in stimulation parameters with increasing beneficial effect on parkinsonism while reducing the threshold for the elicitation of stimulation-induced dyskinaesias. In parallel with improvement of parkinsonism, the levodopa dose can be gradually decreased. As diphasic dystonic dyskinaesias are improved to a greater degree than peak-dose dyskinaesias, both direct and indirect mechanisms may be involved. Peak-dose choreatic dyskinaesias, associated with little evidence of parkinsonism and thus with low neuronal activity in the STN, are improved, mostly indirectly. Fixed off-period dystonia, mobile diphasic dystonia and peak-dose choreodystonia seem to represent a continuous clinical spectrum reflecting a continuous spectrum of underlying activity patterns of STN neurons.
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PMID:From off-period dystonia to peak-dose chorea. The clinical spectrum of varying subthalamic nucleus activity. 1035 65

Although botulinum toxin A was first introduced to treat strabismus and blepherospasm it is now used in an increasing number of conditions, many in the field of pediatrics. Its action results from a prevention of the release of acetylcholine from nerve terminals. A number of studies recording the effects of the toxin in the treatment of spastic cerebral palsy are reviewed, and although these can be criticized, there seems to be no doubt that it can be of benefit. It is few side effects, but it may reveal an underlying weakness. Other disadvantages are its cost and the need for repeated injections. It can be used for the relief of rigidity, although the effects in the extrapyramidal form of cerebral palsy are not so dramatic. Also it can be beneficial in some forms of dystonia, rarely if this is generalized, but certainly if it is focal, and especially if there is accompanying pain. There are several conditions seen in children, such as strabismus, blepherospasm and tremors, in which this form of treatment will rarely be indicated; but they will be mentioned. An exception may be spasmodic torticollis during adolescence if it does not respond to other therapy, as it is so disabling. Botulinum toxin can be used to block the discharges from cholinergic sympathetic and parasympathetic terminals. Focal hyperhidrosis can be very distressing among older children, and the use of the toxin should sometimes be considered in this and other autonomic disorders.
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PMID:The role of botulinus toxin type A in treatment--with special reference to children. 1037 98

In three selected patients with severe complex cervical dystonia, continuous bilateral stimulation of the globus pallidus internus was associated with improvement of cervical dystonia, dystonia-associated pain, and functional disability.
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PMID:Bilateral stimulation of globus pallidus internus for treatment of cervical dystonia. 1048 34

The authors describe a technique for performing partial sectioning and myectomy of the trapezius muscle in patients with severe cervical dystonia that is unresponsive to conservative treatment. Asleep-awake-asleep anesthesia allows intraoperative control of the sectioning procedure to avoid causing postoperative weakness of arm elevation above the horizontal plane. The procedure has been performed successfully in three patients. In all cases the dystonic posture of the shoulder and local pain were improved postoperatively. There were no new deficits. This technique can be used as an adjunct to other peripheral surgical procedures in patients with marked laterocollis and dystonic elevation and ante-version of the shoulder.
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PMID:Partial myotomy/myectomy of the trapezius muscle with an asleep-awake-asleep anesthetic technique for treatment of cervical dystonia. Technical note. 1054 Dec 53

Indirect evidence suggests that the thalamus contributes to abnormal movements occurring in patients with dystonia (dystonia patients). The present study tested the hypothesis that thalamic activity contributes to the dystonic movements that occur in such patients. During these movements, spectral analysis of electromyographic (EMG) signals in flexor and extensor muscles of the wrist and elbow exhibited peak EMG power in the lowest frequency band [0-0.78 Hz (mean: 0.39 Hz) dystonia frequency] for 60-85% of epochs studied during a pointing task. Normal controls showed low-frequency peaks for <16% of epochs during pointing. Among dystonia patients, simultaneous contraction of antagonistic muscles (cocontraction) at dystonia frequency during pointing was observed for muscles acting about the wrist (63% of epochs) and elbow (39%), but cocontraction was not observed among normal controls during pointing. Thalamic neuronal signals were recorded during thalamotomy for treatment of dystonia and were compared with those of control patients without motor abnormality who were undergoing thalamic procedures for treatment of chronic pain. Presumed nuclear boundaries of a human thalamic cerebellar relay nucleus (ventral intermediate, Vim) and a pallidal relay nucleus (ventral oral posterior, Vop) were estimated by aligning the anterior border of the principal sensory nucleus (ventral caudal, Vc) with the region where the majority of cells have cutaneous receptive fields (RFs). The ratio of power at dystonia frequency to average spectral power was >2 (P < 0.001) for cells in presumed Vop often for dystonia patients (81%) but never for control patients. The percentage of such cells in presumed Vim of dystonia patients (32%) was not significantly different from that of controls (31%). Many cells in presumed Vop exhibited dystonia frequency activity that was correlated with and phase-advanced on EMG activity during dystonia, suggesting that this activity was related to dystonia. Thalamic somatic sensory activity also differed between dystonia patients and controls. The percentage of cells responding to passive joint movement or to manipulation of subcutaneous structures (deep sensory cells) in presumed Vim was significantly greater in patients with dystonia than in control patients undergoing surgery for treatment of pain or tremor. Dystonia patients had a significantly higher proportion of deep sensory cells responding to movement of more than one joint (26%, 13/52) than did "control" patients (8%, 4/49). Deep sensory cells in patients with dystonia were located in thalamic maps that demonstrated increased representations of parts of the body affected by dystonia. Thus dystonia patients showed increased receptive fields and an increased thalamic representation of dystonic body parts. The motor activity of an individual sensory cell was related to the sensory activity of that cell by identification of the muscle apparently involved in the cell's receptive field. Specifically, we defined the effector muscle as the muscle that, by contraction, produced the joint movement associated with a thalamic neuronal sensory discharge, when the examiner passively moved the joint. Spike X EMG correlation functions during dystonia indicated that thalamic cellular activity less often was related to EMG in effector muscles (52%) than in other muscles (86%). Thus there is a mismatch between the effector muscle for a thalamic cell and the muscles with EMG correlated with activity of that cell during dystonia. This mismatch may result from the reorganization of sensory maps and may contribute to the simultaneous activation of multiple muscles observed in dystonia. Microstimulation in presumed Vim in dystonia patients produced simultaneous contraction of multiple forearm muscles, similar to the simultaneous muscle contractions observed in dystonia. (ABSTRACT TRUNCATED)
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PMID:Thalamic single neuron activity in patients with dystonia: dystonia-related activity and somatic sensory reorganization. 1056 12

After cervical sprain not only pain and neuropsychological disturbances may occur, but also the following sequelae: cervical dystonia, and torticollis, dizziness, hearing loss for low frequencies, dysphonia and globus. Except for dystonia the symptoms often respond to manipulation of a blocked articulation between occiput and atlas or axis and the third cervical vertebra.
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PMID:[Little known sequelae of sprains of the cervical spine]. 1061 1

Although a referral bias may have resulted in a higher proportion of atypical cases and consequently an overestimation of dystonia, asymmetric limb dystonia particularly affecting one arm initially was observed in 92% of all our CBD cases. Predominant leg dystonia is uncommon, and head, neck, or axial dystonia is rare. Dystonia is often associated with myoclonus, rigidity, apraxia, alien hand phenomenon, and sensory cortical signs in the affected limb, and there are no significant differences between the occurrence of these or other features, between patients with or without dystonia. There is no effective treatment for this relentless disorder except for temporary relief of dystonia and pain with local botulinum toxin injections. Further clinicopathologic studies are needed to elucidate the anatomical and physiologic substrates of dystonia in this disorder.
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PMID:Dystonia in corticobasal degeneration. 1062 71

The authors report the first case of chronic globus pallidus internus (GPi) stimulation for treatment of medically intractable hemidystonia for which long-term follow-up data are available. The patient had developed left-sided low-frequency tremor and hemidystonia after a severe head trauma sustained at 15 years of age. He experienced relief of the tremor but not of the hemidystonia after a thalamotomy was performed in the right hemisphere 3 years postinjury. When the patient was 24 years old, the authors performed a magnetic resonance-guided stereotactic implantation of a monopolar electrode in the right-sided posteroventral GPi. Chronic deep brain stimulation resulted in remarkable improvement of dystonia-associated pain, phasic dystonic movements, and dystonic posture, which was accompanied by functional gain. Postoperative improvement was sustained after 4 years of follow up. Chronic GPi stimulation appears to be a valuable treatment option for posttraumatic dystonia.
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PMID:Long-term follow-up study of chronic globus pallidus internus stimulation for posttraumatic hemidystonia. 1070 34

Early diagnosis is a prerequisite for a successful treatment of complex regional pain syndrome (CRPS). In order to describe neurological symptoms which characterize CRPS, we evaluated 145 patients prospectively. Two-thirds of these were women, the mean age at time of investigation was 50.4 years. CRPS followed limb trauma, surgery and nerve lesion. Employing the current IASP criteria 122 patients were classified as CRPS I and 23 as CRPS II. All patients were assessed clinically pain was quantified using the McGill pain questionnaire, skin temperature was measured by an infrared thermometer and a subgroup of 57 patients was retested in order to determine thermal thresholds (QST). Of our patients 42% reported stressful life events in a close relationship to the onset of CRPS and 41% had a history of chronic pain before CRPS. The latter group of patients gave a higher rating of CRPS pain (P<0.05). The major symptoms were pain at rest in 77% and hyperalgesia in 94%. Typical pain was deep in the limb having a tearing character. Patients getting physical therapy had significantly less pain than those without (P<0.04). Autonomic signs were frequent (98%) and often changed with the duration of CRPS. Skin temperature was warmer in acute and colder in chronic stages (P<0.001). Likewise edema had a higher incidence in acute stages (P<0.001). We found no correlation between pain and autonomic dysfunction. Motor dysfunction (present in 97%) included weakness, tremor, exaggerated tendon reflexes, dystonia or myoclonic jerks. QST revealed increased warm perception thresholds (P<0.02) and decreased cold pain thresholds (P<0.03) of the affected limb. The detailed knowledge of clinical features of CRPS could help physicians early to recognize the disease and thus to improve therapy outcome.
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PMID:Neurological findings in complex regional pain syndromes--analysis of 145 cases. 1077 May 24

Pain, defined as an unpleasant or distressing sensory experience, has been recognized as feature of Parkinson's disease (PD) since the first descriptions of the disorder. Pain is estimated to occur in approximately 40% of patients with PD, and in a minority of individuals becomes severe enough to overshadow the motor symptoms of the disorder. Recent studies based on patients' descriptions of pain have enabled a classification of painful sensations into 1 or more of 5 categories: musculoskeletal pain, neuritic or radicular pain, dystonia-associated pain, primary or central pain, and akathitic discomfort. The existence of a central pain syndrome, intrinsic to PD, finds support in a collection of case reports, but the precise mechanism is unknown, and a correlation with pathology has not been made. This review describes the clinical features of the pain syndromes in PD, and provides a framework for evaluating, classifying, and treating painful symptoms in PD.
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PMID:Pain in Parkinson's disease. 1078 30


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