Cases reported "Parkinson Disease"

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11/78. Irregular jerky tremor, myoclonus, and thalamus: a study using low-frequency stimulation.

    High-frequency thalamic stimulation alleviates tremor in Parkinson's disease (PD) and essential tremor (ET). The origin of thalamic myoclonus is unexplained and the effects of low-frequency thalamic stimulation on movement control are still unknown. We studied the effects of stimulation at a low frequency of 15 Hz in five drug-free patients (3 PD, 2 ET) 6 months after thalamic implantation of quadripolar electrodes (unilateral in four patients, bilateral in one patient). Clinical, electrophysiological, and videotaped assessment, using a monopolar 15 Hz frequency (3 V, 90 micros) stimulation current applied simultaneously through two adjacent contacts of the electrode, was performed. We observed myoclonus and irregular jerky tremor in the upper limb contralateral to the site of stimulation. The jerks lasted less than 200 ms, were irregular and not synchronous with stimulation, were superimposed on rest or postural tremor, and increased in response to tactile, proprioceptive, or vibratory stimuli. The fact that this complex movement disorder can be induced by low-frequency stimulation in the ventral intermediate nucleus (Vim) of the thalamus suggests that it results, at least partly, from dysfunction of the Vim and possibly adjacent nuclei of the thalamus.
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12/78. levodopa motor complications in Parkinson's disease.

    Parkinson's disease (PD) is an age-related neurodegenerative disorder with an average onset age of 60 years. In the united states, approximately one million persons suffer from PD, and there are 60,000 newly diagnosed cases every year. The estimated cost of PD to society is $27 billion per year. Based on united states Census Bureau projections, it is estimated that the frequency of PD will increase fourfold by the year 2040, making it an even larger burden on patients, their families and society.
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13/78. Lacunar infarct during pallidotomy: case report.

    A symptomatic lacunar infarct is an unusual complication which may develop during stereotactically guided pallidotomy using radiofrequency thermoablation. We describe a 54-year-old man with Parkinson's disease involving predominantly the right side, progressively deteriorating under medical management. He underwent stereotactically guided radiofrequency thermoablation of the posteroventral globus pallidus interna. Despite intraoperative microelectrode recording and stimulation, the patient developed right facial weakness and pronator drift during the procedure. MRI showed a small lacunar infarct in the left internal capsule, in addition to the appropriately placed ablative lesion. We discuss the potential mechanisms for this type of injury.
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14/78. DBS and diathermy interaction induces severe CNS damage.

    pulse-modulated radiofrequency diathermy treatment to the maxilla produced permanent diencephalic and brainstem lesions and a vegetative state in a patient with PD with implanted subthalamic electrodes for deep brain stimulation.
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15/78. Contraversive eye deviation during deep brain stimulation of the globus pallidus internus.

    Clinical signs help determine correct electrode positioning during stereotactic implantation for chronic high-frequency pallidal stimulation in Parkinson's diease (PD). The authors describe a patient who had marked, sustained, contraversive eye deviation caused by stimulation during pallidal surgery. The underlying mechanism is probably an excitation of fibers in the internal capsule by volume-conducted current spread. Such conjugate eye deviation is thus not necessarily an indication of incorrect electrode placement.
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16/78. Deep brain stimulator electrodes used for lesioning: proof of principle.

    OBJECTIVE: patients with chronically implanted deep brain stimulator (DBS) electrodes can encounter complications requiring hardware removal. We assessed the safety and efficacy of using implanted DBS electrodes to create a therapeutic lesion before their removal. methods: Revision or removal of the DBS electrodes was required in two patients who had previously undergone DBS implantation. We conducted a series of in vitro experiments to confirm that the DBS electrodes could be used to generate radiofrequency lesions and to assess the relationship between radiofrequency parameters and lesion size. With this information, and with the approval of the hospital ethical review board, implanted electrodes were used to create incremental radiofrequency lesions in the thalamus in one patient and in the subthalamic nucleus in another. The procedures were performed under local anesthesia with contiguous contacts of the DBS lead connected to the active and reference sites of the RF generator to create a bipolar lesion. RESULTS: A 51-year-old man with essential tremor and a thalamic DBS required repeated battery changes secondary to tolerance and high voltage demands. Rather than replacing the battery, a radiofrequency thalamotomy was performed by using the existing left DBS electrode. At the 6-month follow-up examination, successful lesioning provided near complete tremor control. A second patient, a 50-year-old man with Parkinson's disease who had undergone bilateral subthalamic deep brain stimulation, developed skin erosion over the DBS hardware. A subthalamic nucleus lesion was made through the right DBS electrode. Lesion position and size were confirmed with magnetic resonance imaging. CONCLUSION: Lesions can be made through chronically implanted DBS electrodes in a safe, graded fashion and can produce therapeutic benefit.
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17/78. Quantitative assessment of Parkinson's disease deficits.

    OBJECTIVE: To quantitatively analyze the tremor and rigidity due to Parkinson's disease. methods: 38 patients with Parkinson's disease (PD) ranging in age from 45 to 72 years and 211 normal subjects aged from 16 to 76 years were investigated. The frequency and range of tremor, the muscle tone of the upper limbs in elbow were detected by a computerized video motion detecting system and a new invented apparatus which can detects skeletal muscle tone. RESULTS: For the PD patients, the frequency of resting tremors was detected in 4 to 6 per second. For extensor and flexor in the PD patients, the value of muscle tone was higher than that of normal subjects and the value of muscle tone in flexor was higher than that of extensor. The rigidity increased gradually with repeat passive movement. The curves of rigidity were shown on computer screen or printed out. The data of rigidity were compared with the M-A Scale. A patient who was suspected to suffer from PD above by the equipments and found the muscle tone was higher than normal. In another PD patient the rigidity was obvious at one side and the muscle tone in "normal side" was also high. These equipments were used to record changes of rigidity and tremor in one more PD patient taking with different drugs in order to see the drug effect. CONCLUSION: Quantitative methods are useful to analyse the motion disorders due to PD.
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18/78. Complications of gamma knife surgery for parkinson disease.

    BACKGROUND: Many medical centers throughout the world offer radiosurgery with the gamma knife (GK) for pallidotomy and thalamotomy as a safe and effective alternative to radiofrequency ablative surgery and deep brain stimulation for parkinson disease (PD). The reported incidence of significant complications varies considerably, and the long-term complication rate remains unknown. DESIGN: We describe 8 patients seen during an 8-month period referred for complications of GK surgery for PD. RESULTS: Of the 8 patients, 1 died as a result of complications, including dysphagia and aspiration pneumonia. Other complications included hemiplegia, homonymous visual field deficit, hand weakness, dysarthria, hypophonia, aphasia, arm and face numbness, and pseudobulbar laughter. In all patients, lesions were significantly off target. CONCLUSIONS: The 8 patients with PD seen in referral at our center for complications of GK surgery highlight a spectrum of potential problems associated with this procedure. These include lesion accuracy and size and the delayed development of neurological complications secondary to radiation necrosis. Gamma knife surgery may have a higher complication rate than has been previously appreciated due to delayed onset and underreporting. We believe that the risk-benefit ratio of the GK will require further scrutiny when considering pallidotomy or thalamotomy in patients with PD. physicians using this technique should carefully follow up patients postoperatively for delayed complications, and fully inform patients of these potential risks.
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19/78. Mirthful laughter induced by subthalamic nucleus stimulation.

    High-frequency stimulation of the subthalamic nucleus (STN) improves the motor signs of Parkinson's disease (PD). The three main components (motor, associative, and limbic) of the cortical-basal ganglia-cortical circuits pass through the STN. It is not known whether STN stimulation can influence the limbic loop. We present two PD patients in whom acute stimulation of an electrode located in the STN using high stimulation parameters (50% higher than therapeutic) induced funny associations, leading to infectious laughter and hilarity, whereas the therapeutic parameters induced a hypomanic behavior and marked improvement of akinesia. Our report suggests that the STN, with its sensorimotor, cognitive, and limbic parts is not only involved in motor, but also in psychomotor regulation.
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20/78. Fast orthostatic tremor in Parkinson's disease mimicking primary orthostatic tremor.

    Leg tremor during standing is a rare feature in idiopathic Parkinson's disease (PD). Tremor during standing usually has a low frequency (range, 4-6 Hz), similar to PD rest tremor frequency, and is improved by levodopa. We describe three cases of fast orthostatic tremor (FoT) of legs and trunk mimicking primary orthostatic tremor (OT) in patients treated with levodopa for PD. Asymmetrical akinetorigid syndrome was accompanied by a rest tremor in two cases. We obtained electrophysiological parameters by electromyographic (EMG) polygraphic recording after 16 hours withdrawal of antiparkinsonian treatment and at the maximal effect of levodopa in order to investigate the effect of dopaminergic stimulation upon such cases of orthostatic tremor in PD. Electrophysiological parameters of orthostatic tremor, especially frequency (range 14-18 Hz), were similar to that seen in POT. Severity of tremor was independent of seriousness and duration of PD. levodopa had no effect either on the handicap due to OT or on the amplitude and frequency of the EMG OT activity. In contrast, mild improvement of OT was obtained with benzodiazepines in two cases and parkinsonian syndrome was levodopa-sensitive. These findings suggest that FoT in PD would not be directly controlled by the dopaminergic system. However, increased rhythmicities in basal ganglia or in cerebello-thalamic loops at the rapid frequencies range seen in PD could favor the emergence of a primary orthostatic tremor-like tremor in PD patients.
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