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A L Benabid - One of the best experts on this subject based on the ideXlab platform.
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Effect of bilateral stimulation of the Subthalamic Nucleus on parkinsonian dysarthria
Brain and Language, 2003Co-Authors: Michèle Gentil, Pierre Pollak, Serge Pinto, A L BenabidAbstract:Never was the effect of bilateral stimulation of the Subthalamic Nucleus (STN) evaluated quantitatively on all the components of speech production, that is articulation, respiration and phonation, at the same time. It is the purpose of this study which uses force measurements of the articulatory organs and acoustic analysis in 16 parkinsonian patients. With STN stimulation, reaction and movement time of the articulatory organs decreased and their maximal strength, as well as their precision increased. We also noted a large beneficial effect on voice with a significant improvement in respiratory and phonatory functions.
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effect of high frequency stimulation of the Subthalamic Nucleus on the neuronal activities of the substantia nigra pars reticulata and ventrolateral Nucleus of the thalamus in the rat
Neuroscience, 2000Co-Authors: Abdelhamid Benazzouz, Brigitte Piallat, D M Gao, Rabia Boualibenazzouz, A L BenabidAbstract:Electrophysiological recordings were made in anaesthetized rats to investigate the mode of function of high-frequency stimulation of the Subthalamic Nucleus used as a therapeutic approach for Parkinson's disease. High-frequency electrical stimulation of the Subthalamic Nucleus (130 Hz) induced a net decrease in activity of all cells recorded around the site of stimulation in the Subthalamic Nucleus. It also caused an inhibition of the majority of neurons recorded in the substantia nigra pars reticulata in normal rats (94%) and in rats with 6-hydroxydopamine lesions of the substantia nigra pars compacta (90%) or with ibotenic acid lesions of the globus pallidus (79.5%). The majority of cells recorded in the ventrolateral Nucleus of the thalamus responded with an increase in their activity (84%). These results show that high-frequency stimulation of the Subthalamic Nucleus induces a reduction of the excitatory glutamatergic output from the Subthalamic Nucleus which results in deactivation of substantia nigra pars reticulata neurons. The reduction in tonic inhibitory drive of nigral neurons induces a disinhibition of activity in the ventrolateral motor thalamic Nucleus, which should result in activation of the motor cortical system.
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high frequency stimulation of the Subthalamic Nucleus suppresses experimental resting tremor in the monkey
Neuroscience, 1999Co-Authors: Dongming Gao, Abdelhamid Benazzouz, Brigitte Piallat, Karine Bressand, Igor A Ilinsky, Kristy Kultasilinsky, A L BenabidAbstract:The effect of high-frequency stimulation of the Subthalamic Nucleus on parkinsonian-like resting tremor was investigated in two monkeys (Macaca fascicularis). Unilateral tremor of the arm and leg was induced by electrical coagulation of the brainstem area including the substantia nigra and the red Nucleus. The tremor was only seen at rest condition with a very stable frequency of 4.46+/-0.59 Hz (mean+/-S.D.). Apomorphine (0.10-0.4 mg/kg, s.c.) completely blocked the tremor, suggesting that it was a dopaminergic-dependent symptom just like the parkinsonian tremor. When the stimulating frequency varied from 20 to 1000 Hz, both mono- and bipolar stimulation (square pulses, 0-5 mA, 0.06 ms) of the Subthalamic Nucleus suppressed resting tremor in a frequency-dependent manner but monopolar stimulation was more effective. These effects remained stable for more than two years. The present results suggest that the Subthalamic Nucleus is involved in the control and mechanism of resting tremor and that the high-frequency stimulation of the Subthalamic Nucleus can be used as an alternative therapy in parkinsonian patients with akinesia, rigidity and resting tremor.
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electrical stimulation of the Subthalamic Nucleus in advanced parkinson s disease
The New England Journal of Medicine, 1998Co-Authors: Patricia Limousin, Abdelhamid Benazzouz, Paul Krack, Pierre Pollak, Claire Ardouin, D Hoffmann, A L BenabidAbstract:Background In many patients with idiopathic Parkinson's disease, treatment with levodopa is complicated by fluctuations between an “off” period (also referred to as “off medication”), when the medication is not working and the motor symptoms of parkinsonism are present, and an “on” period, when the medication is causing improved mobility (also referred to as “on medication”), often accompanied by debilitating dyskinesias. In animal models of Parkinson's disease, there is overactivity in the Subthalamic Nucleus, and electrical stimulation of the Subthalamic Nucleus improves parkinsonism. We therefore sought to determine the efficacy and safety of electrical stimulation of the Subthalamic Nucleus in patients with Parkinson's disease. Methods We studied 24 patients with idiopathic Parkinson's disease in whom electrodes were implanted bilaterally in the Subthalamic Nucleus under stereotactic guidance with imaging and electrophysiologic testing of the location. Twenty were followed for at least 12 months. Clin...
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electrical stimulation of the Subthalamic Nucleus in advanced parkinson s disease
The New England Journal of Medicine, 1998Co-Authors: Patricia Limousin, Abdelhamid Benazzouz, Paul Krack, Pierre Pollak, Claire Ardouin, D Hoffmann, A L BenabidAbstract:BACKGROUND: In many patients with idiopathic Parkinson's disease, treatment with levodopa is complicated by fluctuations between an "off" period, when the medication is not working and the motor symptoms of parkinsonism are present, and an "on" period, when the medication is causing improved mobility, often accompanied by debilitating dyskinesias. In animal models of Parkinson's disease, there is overactivity in the Subthalamic Nucleus, and electrical stimulation of the Subthalamic Nucleus improves parkinsonism. We therefore sought to determine the efficacy and safety of electrical stimulation of the Subthalamic Nucleus in patients with Parkinson's disease. METHODS: We studied 24 patients with idiopathic Parkinson's disease in whom electrodes were implanted bilaterally in the Subthalamic Nucleus under stereotactic guidance with imaging and electrophysiologic testing of the location. Twenty were followed for at least 12 months. Clinical evaluations included the Unified Parkinson's Disease Rating Scale, a dyskinesia scale, and timed tests conducted before and after surgery, when patients were off and on medications. RESULTS: After one year of electrical stimulation of the Subthalamic Nucleus, the patients' scores for activities of daily living and motor examination scores (Unified Parkinson's Disease Rating Scale parts II and III, respectively) off medication improved by 60 percent (P<0.001). The subscores improved for limb akinesia, rigidity, tremor, and gait. In the testing done on medication, the scores on part III improved by 10 percent (P<0.005). The mean dose of dopaminergic drugs was reduced by half. The cognitive-performance scores remained unchanged, but one patient had paralysis and aphasia after an intracerebral hematoma during the implantation procedure. CONCLUSIONS: Electrical stimulation of the Subthalamic Nucleus is an effective treatment for advanced Parkinson's disease. The severity of symptoms off medication decreases, and the dose of levodopa can be reduced with consequent reduction in dyskinesias.
Abdelhamid Benazzouz - One of the best experts on this subject based on the ideXlab platform.
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five year follow up of bilateral stimulation of the Subthalamic Nucleus in advanced parkinson s disease
The New England Journal of Medicine, 2003Co-Authors: Paul Krack, Patricia Limousin, Abdelhamid Benazzouz, Claire Ardouin, Alina Batir, Nadege Van Blercom, Stephan Chabardes, Valerie Fraix, Adnan Koudsie, J F LebasAbstract:background Although the short-term benefits of bilateral stimulation of the Subthalamic Nucleus in patients with advanced Parkinson’s disease have been well documented, the long-term outcomes of the procedure are unknown. methods We conducted a five-year prospective study of the first 49 consecutive patients whom we treated with bilateral stimulation of the Subthalamic Nucleus. Patients were assessed at one, three, and five years with levodopa (on medication) and without levodopa (off medication), with use of the Unified Parkinson’s Disease Rating Scale. Seven patients did not complete the study: three died, and four were lost to follow-up. results As compared with base line, the patients’ scores at five years for motor function while off medication improved by 54 percent (P<0.001) and those for activities of daily living improved by 49 percent (P<0.001). Speech was the only motor function for which offmedication scores did not improve. The scores for motor function on medication did not improve one year after surgery, except for the dyskinesia scores. On-medication akinesia, speech, postural stability, and freezing of gait worsened between year 1 and year 5 (P<0.001 for all comparisons). At five years, the dose of dopaminergic treatment and the duration and severity of levodopa-induced dyskinesia were reduced, as compared with base line (P<0.001 for each comparison). The average scores for cognitive performance remained unchanged, but dementia developed in three patients after three years. Mean depression scores remained unchanged. Severe adverse events included a large intracerebral hemorrhage in one patient. One patient committed suicide. conclusions Patients with advanced Parkinson’s disease who were treated with bilateral stimulation of the Subthalamic Nucleus had marked improvements over five years in motor function while off medication and in dyskinesia while on medication. There was no control group, but worsening of akinesia, speech, postural stability, freezing of gait, and cognitive function between the first and the fifth year is consistent with the natural history of Parkinson’s disease.
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electrophysiological and metabolic evidence that high frequency stimulation of the Subthalamic Nucleus bridles neuronal activity in the Subthalamic Nucleus and the substantia nigra reticulata
The FASEB Journal, 2003Co-Authors: Thomas Boraud, Bernard Bioulac, Christian E Gross, Erwan Bezard, Abdelhamid BenazzouzAbstract:High-frequency stimulation (HFS) of the Subthalamic Nucleus (STN) has been shown to produce a dramatic alleviation of motor symptoms in patients with advanced Parkinson’s disease. Its functional me...
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effect of high frequency stimulation of the Subthalamic Nucleus on the neuronal activities of the substantia nigra pars reticulata and ventrolateral Nucleus of the thalamus in the rat
Neuroscience, 2000Co-Authors: Abdelhamid Benazzouz, Brigitte Piallat, D M Gao, Rabia Boualibenazzouz, A L BenabidAbstract:Electrophysiological recordings were made in anaesthetized rats to investigate the mode of function of high-frequency stimulation of the Subthalamic Nucleus used as a therapeutic approach for Parkinson's disease. High-frequency electrical stimulation of the Subthalamic Nucleus (130 Hz) induced a net decrease in activity of all cells recorded around the site of stimulation in the Subthalamic Nucleus. It also caused an inhibition of the majority of neurons recorded in the substantia nigra pars reticulata in normal rats (94%) and in rats with 6-hydroxydopamine lesions of the substantia nigra pars compacta (90%) or with ibotenic acid lesions of the globus pallidus (79.5%). The majority of cells recorded in the ventrolateral Nucleus of the thalamus responded with an increase in their activity (84%). These results show that high-frequency stimulation of the Subthalamic Nucleus induces a reduction of the excitatory glutamatergic output from the Subthalamic Nucleus which results in deactivation of substantia nigra pars reticulata neurons. The reduction in tonic inhibitory drive of nigral neurons induces a disinhibition of activity in the ventrolateral motor thalamic Nucleus, which should result in activation of the motor cortical system.
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high frequency stimulation of the Subthalamic Nucleus suppresses experimental resting tremor in the monkey
Neuroscience, 1999Co-Authors: Dongming Gao, Abdelhamid Benazzouz, Brigitte Piallat, Karine Bressand, Igor A Ilinsky, Kristy Kultasilinsky, A L BenabidAbstract:The effect of high-frequency stimulation of the Subthalamic Nucleus on parkinsonian-like resting tremor was investigated in two monkeys (Macaca fascicularis). Unilateral tremor of the arm and leg was induced by electrical coagulation of the brainstem area including the substantia nigra and the red Nucleus. The tremor was only seen at rest condition with a very stable frequency of 4.46+/-0.59 Hz (mean+/-S.D.). Apomorphine (0.10-0.4 mg/kg, s.c.) completely blocked the tremor, suggesting that it was a dopaminergic-dependent symptom just like the parkinsonian tremor. When the stimulating frequency varied from 20 to 1000 Hz, both mono- and bipolar stimulation (square pulses, 0-5 mA, 0.06 ms) of the Subthalamic Nucleus suppressed resting tremor in a frequency-dependent manner but monopolar stimulation was more effective. These effects remained stable for more than two years. The present results suggest that the Subthalamic Nucleus is involved in the control and mechanism of resting tremor and that the high-frequency stimulation of the Subthalamic Nucleus can be used as an alternative therapy in parkinsonian patients with akinesia, rigidity and resting tremor.
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electrical stimulation of the Subthalamic Nucleus in advanced parkinson s disease
The New England Journal of Medicine, 1998Co-Authors: Patricia Limousin, Abdelhamid Benazzouz, Paul Krack, Pierre Pollak, Claire Ardouin, D Hoffmann, A L BenabidAbstract:Background In many patients with idiopathic Parkinson's disease, treatment with levodopa is complicated by fluctuations between an “off” period (also referred to as “off medication”), when the medication is not working and the motor symptoms of parkinsonism are present, and an “on” period, when the medication is causing improved mobility (also referred to as “on medication”), often accompanied by debilitating dyskinesias. In animal models of Parkinson's disease, there is overactivity in the Subthalamic Nucleus, and electrical stimulation of the Subthalamic Nucleus improves parkinsonism. We therefore sought to determine the efficacy and safety of electrical stimulation of the Subthalamic Nucleus in patients with Parkinson's disease. Methods We studied 24 patients with idiopathic Parkinson's disease in whom electrodes were implanted bilaterally in the Subthalamic Nucleus under stereotactic guidance with imaging and electrophysiologic testing of the location. Twenty were followed for at least 12 months. Clin...
Francisco Grandas - One of the best experts on this subject based on the ideXlab platform.
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dopamine dysregulation syndrome after deep brain stimulation of the Subthalamic Nucleus in parkinson s disease
Journal of the Neurological Sciences, 2012Co-Authors: Beatriz De La Casafages, Francisco GrandasAbstract:Dopamine dysregulation syndrome is a complication of the dopaminergic treatment for Parkinson's disease, probably related to sensitization of the mesolimbic dopamine system. The relationship between dopamine dysregulation syndrome and deep brain stimulation of the Subthalamic Nucleus remains unclear. We report three patients with Parkinson's disease who developed de novo dopamine dysregulation syndrome after deep brain stimulation of the Subthalamic Nucleus. We hypothesized that the combined effect of dopaminergic replacement therapy and deep brain stimulation on the limbic territory of the Subthalamic Nucleus could have precipitated the dopamine dysregulation syndrome in these patients, by inducing hyperstimulation of the mesolimbic dopamine system. The outcome of postoperative dopamine dysregulation syndrome is poor despite deep brain stimulation adjustments, attempts to reduce the dose of dopaminergic drugs and the addition of quetiapine or antidepressants.
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dopamine dysregulation syndrome and deep brain stimulation of the Subthalamic Nucleus in parkinson s disease
Neurology Research International, 2011Co-Authors: Beatriz De La Casafages, Francisco GrandasAbstract:Dopamine dysregulation syndrome is a complication of the dopaminergic treatment in Parkinson's disease that may be very disabling due to the negative impact that compulsive medication use may have on patients' social, psychological, and physical functioning. The relationship between Subthalamic Nucleus deep brain stimulation and dopamine dysregulation syndrome in patients with Parkinson's disease remains unclear. Deep brain stimulation may improve, worsen, or have no effect on preoperative dopamine dysregulation syndrome. Moreover, dopamine dysregulation syndrome may appear for the first time after deep brain stimulation of the Subthalamic Nucleus. The outcome of postoperative dopamine dysregulation syndrome is poor despite stimulation and medication adjustments. Here we review the phenomenology and neurobiology of this disorder, discuss possible mechanisms that may underlie the diverse outcomes of dopamine dysregulation syndrome after Subthalamic Nucleus deep brain stimulation, and propose management strategies.
Albert Gjedde - One of the best experts on this subject based on the ideXlab platform.
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stimulation of Subthalamic Nucleus inhibits emotional activation of fusiform gyrus
NeuroImage, 2006Co-Authors: Jacob Geday, Karen Ostergaard, Albert GjeddeAbstract:Abstract In patients with Parkinson’s disease, deep brain stimulation of the Subthalamic Nucleus is known to impair their ability to correctly identify facial expressions of negative emotions. This difficulty exists only when the stimulator is active. The reason for the impairment is unknown. To test the hypothesis that the stimulation itself is responsible, we used positron emission tomography to compare functional activations of brain regions in nine patients with Parkinson’s disease treated with surgically implanted electrodes into both Subthalamic nuclei, and 22 healthy volunteers. Both groups viewed images with neutral or emotional content from Aarhus University’s standard Empathy Picture System ( www.geday.net/eps ) with 360 images of people in pleasant, unpleasant or neutral real-life situations, presenting either the situations or close-ups of the facial expressions of the people involved. Both groups, the patients with stimulation OFF and the healthy volunteers, had raised regional blood flow rates (rCBF) in the right fusiform gyrus when they viewed emotionally expressive faces compared to neutral faces. With stimulation turned on, this response was significantly inhibited in the patients because of a raised rCBF at baseline during the neutral faces. Stimulation of the STN did not alter fusiform reaction to emotionally pregnant scenes; nor did healthy volunteers and patients react differently to these stimuli regardless of stimulation status. Also, STN stimulation raised the emotional activation of the anterior cingulate and lowered the activity of the putamen. The findings suggest that the stimulation of the Subthalamic Nucleus interferes with the integration of specific neocortical networks involved in the recognition of facial expressions.
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stimulation of Subthalamic Nucleus inhibits emotional activation of fusiform gyrus
NeuroImage, 2006Co-Authors: Jacob Geday, Karen Ostergaard, Albert GjeddeAbstract:Abstract In patients with Parkinson’s disease, deep brain stimulation of the Subthalamic Nucleus is known to impair their ability to correctly identify facial expressions of negative emotions. This difficulty exists only when the stimulator is active. The reason for the impairment is unknown. To test the hypothesis that the stimulation itself is responsible, we used positron emission tomography to compare functional activations of brain regions in nine patients with Parkinson’s disease treated with surgically implanted electrodes into both Subthalamic nuclei, and 22 healthy volunteers. Both groups viewed images with neutral or emotional content from Aarhus University’s standard Empathy Picture System ( www.geday.net/eps ) with 360 images of people in pleasant, unpleasant or neutral real-life situations, presenting either the situations or close-ups of the facial expressions of the people involved. Both groups, the patients with stimulation OFF and the healthy volunteers, had raised regional blood flow rates (rCBF) in the right fusiform gyrus when they viewed emotionally expressive faces compared to neutral faces. With stimulation turned on, this response was significantly inhibited in the patients because of a raised rCBF at baseline during the neutral faces. Stimulation of the STN did not alter fusiform reaction to emotionally pregnant scenes; nor did healthy volunteers and patients react differently to these stimuli regardless of stimulation status. Also, STN stimulation raised the emotional activation of the anterior cingulate and lowered the activity of the putamen. The findings suggest that the stimulation of the Subthalamic Nucleus interferes with the integration of specific neocortical networks involved in the recognition of facial expressions.
Patricia Limousin - One of the best experts on this subject based on the ideXlab platform.
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localization of beta and high frequency oscillations within the Subthalamic Nucleus region
NeuroImage: Clinical, 2017Co-Authors: Thomas Foltynie, Marwan Hariz, Patricia Limousin, B C M Van Wijk, Alek Pogosyan, Harith Akram, Andreas HornAbstract:Parkinsonian bradykinesia and rigidity are typically associated with excessive beta band oscillations in the Subthalamic Nucleus. Recently another spectral peak has been identified that might be im ...
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Subthalamic Nucleus phase amplitude coupling correlates with motor impairment in parkinson s disease
Clinical Neurophysiology, 2016Co-Authors: Bernadette C M Van Wijk, Martijn Beudel, Ashwani Jha, Ashwini Oswal, Thomas Foltynie, Marwan Hariz, Patricia LimousinAbstract:Abstract Objective High-amplitude beta band oscillations within the Subthalamic Nucleus are frequently associated with Parkinson’s disease but it is unclear how they might lead to motor impairments. Here we investigate a likely pathological coupling between the phase of beta band oscillations and the amplitude of high-frequency oscillations around 300 Hz. Methods We analysed an extensive data set comprising resting-state recordings obtained from deep brain stimulation electrodes in 33 patients before and/or after taking dopaminergic medication. We correlated mean values of spectral power and phase–amplitude coupling with severity of hemibody bradykinesia/rigidity. In addition, we used simultaneously recorded magnetoencephalography to look at functional interactions between the Subthalamic Nucleus and ipsilateral motor cortex. Results Beta band power and phase–amplitude coupling within the Subthalamic Nucleus correlated positively with severity of motor impairment. This effect was more pronounced within the low-beta range, whilst coherence between Subthalamic Nucleus and motor cortex was dominant in the high-beta range. Conclusions We speculate that the beta band might impede pro-kinetic high-frequency activity patterns when phase–amplitude coupling is prominent. Furthermore, results provide evidence for a functional subdivision of the beta band into low and high frequencies. Significance Our findings contribute to the interpretation of oscillatory activity within the cortico-basal ganglia circuit.
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Event-related beta desynchronization in human Subthalamic Nucleus correlates with motor performance.
Brain, 2004Co-Authors: Andrea A. Kühn, Marwan Hariz, Patricia Limousin, David Williams, Andreas Kupsch, Gerd-helge Schneider, Kielan Yarrow, Peter BrownAbstract:Summary Although the basal ganglia play an important role in self-generated movement, their involvement in externally paced voluntary movement is less clear. We recorded local field potentials (LFPs) from the region of the Subthalamic nuclei of eight patients with Parkinson’s disease during the performance of a warned reaction time task in which an imperative cue instructed the subject to move or not to move. In ‘go’ trials, LFP activity in the beta frequency band (~20 Hz) decreased prior to movement, with an onset latency that strongly correlated with mean reaction time across patients. This was followed by a late post-movement increase in beta power. In contrast, in ‘nogo’ trials the beta power drop following imperative signals was prematurely terminated compared with go trials and reversed into an early beta power increase. These differences were manifest as power increases when go trials were subtracted from nogo trials. In six patients these relative beta power increases in nogo‐go difference trials were of shorter latency than the respective reaction time. The findings suggest that, firstly, the Subthalamic Nucleus is involved in the preparation of externally paced voluntary movements in humans and, secondly, the degree of synchronization of Subthalamic Nucleus activity in the beta band may be an important determinant of whether motor programming and movement initiation is favoured or suppressed.
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five year follow up of bilateral stimulation of the Subthalamic Nucleus in advanced parkinson s disease
The New England Journal of Medicine, 2003Co-Authors: Paul Krack, Patricia Limousin, Abdelhamid Benazzouz, Claire Ardouin, Alina Batir, Nadege Van Blercom, Stephan Chabardes, Valerie Fraix, Adnan Koudsie, J F LebasAbstract:background Although the short-term benefits of bilateral stimulation of the Subthalamic Nucleus in patients with advanced Parkinson’s disease have been well documented, the long-term outcomes of the procedure are unknown. methods We conducted a five-year prospective study of the first 49 consecutive patients whom we treated with bilateral stimulation of the Subthalamic Nucleus. Patients were assessed at one, three, and five years with levodopa (on medication) and without levodopa (off medication), with use of the Unified Parkinson’s Disease Rating Scale. Seven patients did not complete the study: three died, and four were lost to follow-up. results As compared with base line, the patients’ scores at five years for motor function while off medication improved by 54 percent (P<0.001) and those for activities of daily living improved by 49 percent (P<0.001). Speech was the only motor function for which offmedication scores did not improve. The scores for motor function on medication did not improve one year after surgery, except for the dyskinesia scores. On-medication akinesia, speech, postural stability, and freezing of gait worsened between year 1 and year 5 (P<0.001 for all comparisons). At five years, the dose of dopaminergic treatment and the duration and severity of levodopa-induced dyskinesia were reduced, as compared with base line (P<0.001 for each comparison). The average scores for cognitive performance remained unchanged, but dementia developed in three patients after three years. Mean depression scores remained unchanged. Severe adverse events included a large intracerebral hemorrhage in one patient. One patient committed suicide. conclusions Patients with advanced Parkinson’s disease who were treated with bilateral stimulation of the Subthalamic Nucleus had marked improvements over five years in motor function while off medication and in dyskinesia while on medication. There was no control group, but worsening of akinesia, speech, postural stability, freezing of gait, and cognitive function between the first and the fifth year is consistent with the natural history of Parkinson’s disease.
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electrical stimulation of the Subthalamic Nucleus in advanced parkinson s disease
The New England Journal of Medicine, 1998Co-Authors: Patricia Limousin, Abdelhamid Benazzouz, Paul Krack, Pierre Pollak, Claire Ardouin, D Hoffmann, A L BenabidAbstract:Background In many patients with idiopathic Parkinson's disease, treatment with levodopa is complicated by fluctuations between an “off” period (also referred to as “off medication”), when the medication is not working and the motor symptoms of parkinsonism are present, and an “on” period, when the medication is causing improved mobility (also referred to as “on medication”), often accompanied by debilitating dyskinesias. In animal models of Parkinson's disease, there is overactivity in the Subthalamic Nucleus, and electrical stimulation of the Subthalamic Nucleus improves parkinsonism. We therefore sought to determine the efficacy and safety of electrical stimulation of the Subthalamic Nucleus in patients with Parkinson's disease. Methods We studied 24 patients with idiopathic Parkinson's disease in whom electrodes were implanted bilaterally in the Subthalamic Nucleus under stereotactic guidance with imaging and electrophysiologic testing of the location. Twenty were followed for at least 12 months. Clin...
