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1.
Transl Psychiatry ; 1: e5, 2011 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-22832400

RESUMO

Functional and connectivity changes in corticostriatal systems have been reported in the brains of patients with obsessive-compulsive disorder (OCD); however, the relationship between basal ganglia activity and OCD severity has never been adequately established. We recently showed that deep brain stimulation of the subthalamic nucleus (STN), a central basal ganglia nucleus, improves OCD. Here, single-unit subthalamic neuronal activity was analysed in 12 OCD patients, in relation to the severity of obsessions and compulsions and response to STN stimulation, and compared with that obtained in 12 patients with Parkinson's disease (PD). STN neurons in OCD patients had lower discharge frequency than those in PD patients, with a similar proportion of burst-type activity (69 vs 67%). Oscillatory activity was present in 46 and 68% of neurons in OCD and PD patients, respectively, predominantly in the low-frequency band (1-8 Hz). In OCD patients, the bursty and oscillatory subthalamic neuronal activity was mainly located in the associative-limbic part. Both OCD severity and clinical improvement following STN stimulation were related to the STN neuronal activity. In patients with the most severe OCD, STN neurons exhibited bursts with shorter duration and interburst interval, but higher intraburst frequency, and more oscillations in the low-frequency bands. In patients with best clinical outcome with STN stimulation, STN neurons displayed higher mean discharge, burst and intraburst frequencies, and lower interburst interval. These findings are consistent with the hypothesis of a dysfunction in the associative-limbic subdivision of the basal ganglia circuitry in OCD's pathophysiology.


Assuntos
Gânglios da Base/fisiopatologia , Estimulação Encefálica Profunda/métodos , Neurônios/patologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Doença de Parkinson/fisiopatologia , Índice de Gravidade de Doença , Adulto , Gânglios da Base/patologia , Gânglios da Base/cirurgia , Estimulação Encefálica Profunda/instrumentação , Eletrodos Implantados , Humanos , Transtorno Obsessivo-Compulsivo/patologia , Transtorno Obsessivo-Compulsivo/terapia , Doença de Parkinson/patologia , Doença de Parkinson/terapia , Resultado do Tratamento
2.
Rev Neurol (Paris) ; 165(1): 81-5, 2009 Jan.
Artigo em Francês | MEDLINE | ID: mdl-18808774

RESUMO

INTRODUCTION: Rest tremor, one of the main symptoms in Parkinson's disease (PD), is dramatically improved following subthalamic nucleus stimulation (STN). Results are often better than after l-dopa treatment. The occurrence of rest tremor after neurosurgery in patients without preoperative tremor is uncommon. AIM: The aim of this work was to investigate the role of subthalamic nucleus stimulation in the appearance of parkinsonian rest tremor. PATIENTS-RESULTS: Thirty PD patients (14%) out of 215 undergoing STN deep brain stimulation had an akinetorigid form of the disease, without preoperative tremor 11 years after onset of the disease. Six of them experienced the appearance of tremor six months after bilateral STN stimulation when the stimulator was switched off in the Off medication state. This de novo parkinsonian tremor was improved by l-dopa treatment and disappeared when the stimulator was turned on. CONCLUSION: This finding suggests that infraclinical parkinsonian tremor is probably present in all PD patients.


Assuntos
Tumor de Resto Suprarrenal/diagnóstico , Estimulação Encefálica Profunda , Doença de Parkinson/diagnóstico , Núcleo Subtalâmico/fisiologia , Antiparkinsonianos/uso terapêutico , Feminino , Humanos , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Rigidez Muscular/etiologia , Procedimentos Neurocirúrgicos , Tremor/etiologia
3.
Neurology ; 68(4): 267-71, 2007 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-17151341

RESUMO

BACKGROUND: Stimulation of the subthalamic nucleus is an effective treatment for advanced Parkinson disease (PD) and is currently performed after a mean disease duration of 14 years, when severe motor complications have resulted in marked loss of quality of life. We examined whether surgery at an early stage would maintain quality of life as well as improve motor function. METHODS: Twenty patients with PD of short duration (time elapsed since first symptom +/- SD: 6.8 +/- 1.0 years) with mild to moderate motor signs (Unified Parkinson's Disease Rating Scale III "off" medication: 29 +/- 12) who responded well to levodopa treatment were included in pairs, matched for age, duration and severity of disease, and impairment in socioprofessional functioning. Patients were prospectively randomized to undergo bilateral subthalamic nucleus stimulation (n = 10) or receive optimized medical treatment (n = 10). Parkinsonian motor scores, quality of life, cognition, and psychiatric morbidity were assessed at inclusion and at 6, 12, and 18 months after randomization. RESULTS: Quality of life was improved by 24% in surgical and 0% in nonsurgical patients (p < 0.05). After 18 months, the severity of parkinsonian motor signs "off" medication, levodopa-induced motor complications, and daily levodopa dose were reduced by 69%, 83%, and 57% in operated patients and increased by 29%, 15%, and 12% in the group with medical treatment only (p < 0.001). Adverse events were mild or transient, and overall psychiatric morbidity and anxiety improved in the surgical group. CONCLUSIONS: Subthalamic nucleus stimulation should be considered a therapeutic option early in the course of Parkinson disease.


Assuntos
Procedimentos Neurocirúrgicos/métodos , Doença de Parkinson/terapia , Atividades Cotidianas/psicologia , Adulto , Antiparkinsonianos/uso terapêutico , Estimulação Encefálica Profunda , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Doença de Parkinson/psicologia , Estudos Prospectivos , Qualidade de Vida/psicologia , Núcleo Subtalâmico/fisiologia , Fatores de Tempo
4.
J Neurol Neurosurg Psychiatry ; 76(12): 1640-4, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16291886

RESUMO

BACKGROUND: The short term benefits of bilateral stimulation of the subthalamic nucleus (STN) in patients with advanced levodopa responsive Parkinson's disease (PD) are well documented, but long term benefits are still uncertain. OBJECTIVES: This study provides a 5 year follow up of PD patients treated with stimulation of the STN. METHODS: Thirty seven consecutive patients with PD treated with bilateral STN stimulation were assessed prospectively 6, 24, and 60 months after neurosurgery. Parkinsonian motor disability was evaluated with and without levodopa treatment, with and without bilateral STN stimulation. Neuropsychological and mood assessments included the Mattis Dementia Rating Scale, the frontal score, and the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: No severe peri- or immediate postoperative side effects were observed. Six patients died and one was lost to follow up. Five years after neurosurgery: (i) activity of daily living (Unified Parkinson Disease Rating Scale (UPDRS) II) was improved by stimulation of the STN by 40% ("off" drug) and 60% ("on" drug); (ii) parkinsonian motor disability (UPDRS III) was improved by 54% ("off" drug) and 73% ("on" drug); (iii) the severity of levodopa related motor complications was decreased by 67% and the levodopa daily doses were reduced by 58%. The MADRS was unchanged, but cognitive performance declined significantly. Persisting adverse effects included eyelid opening apraxia, weight gain, addiction to levodopa treatment, hypomania and disinhibition, depression, dysarthria, dyskinesias, and apathy. CONCLUSIONS: Despite moderate motor and cognitive decline, probably due to disease progression, the marked improvement in motor function observed postoperatively was sustained 5 years after neurosurgery.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson/terapia , Núcleo Subtalâmico , Atividades Cotidianas , Idoso , Antiparkinsonianos/uso terapêutico , Transtornos Cognitivos/etiologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Transtornos das Habilidades Motoras , Resultado do Tratamento
5.
Brain ; 128(Pt 10): 2240-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15975946

RESUMO

Deep brain stimulation (DBS) is associated with significant improvement of motor complications in patients with severe Parkinson's disease after some 6-12 months of treatment. Long-term results in a large number of patients have been reported only from a single study centre. We report 69 Parkinson's disease patients treated with bilateral DBS of the subthalamic nucleus (STN, n = 49) or globus pallidus internus (GPi, n = 20) included in a multicentre study. Patients were assessed preoperatively and at 1 year and 3-4 years after surgery. The primary outcome measure was the change in the 'off' medication score of the Unified Parkinson's Disease Rating Scale motor part (UPDRS-III) at 3-4 years. Stimulation of the STN or GPi induced a significant improvement (50 and 39%; P < 0.0001) of the 'off' medication UPDRS-III score at 3-4 years with respect to baseline. Stimulation improved cardinal features and activities of daily living (ADL) (P < 0.0001 and P < 0.02 for STN and GPi, respectively) and prolonged the 'on' time spent with good mobility without dyskinesias (P < 0.00001). Daily dosage of levodopa was significantly reduced (35%) in the STN-treated group only (P < 0.001). Comparison of the improvement induced by stimulation at 1 year with 3-4 years showed a significant worsening in the 'on' medication motor states of the UPDRS-III, ADL and gait in both STN and GPi groups, and speech and postural stability in the STN-treated group. Adverse events (AEs) included cognitive decline, speech difficulty, instability, gait disorders and depression. These were more common in patients treated with DBS of the STN. No patient abandoned treatment as a result of these side effects. This experience, which represents the first multicentre study assessing the long-term efficacy of either STN or GPi stimulation, shows a significant and substantial clinically important therapeutic benefit for at least 3-4 years in a large cohort of patients with severe Parkinson's disease.


Assuntos
Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Atividades Cotidianas , Adulto , Idoso , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Encéfalo/fisiopatologia , Estimulação Encefálica Profunda/efeitos adversos , Discinesia Induzida por Medicamentos/fisiopatologia , Discinesia Induzida por Medicamentos/terapia , Eletrodos Implantados , Feminino , Seguimentos , Globo Pálido/fisiopatologia , Humanos , Levodopa/efeitos adversos , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
6.
J Neurol Neurosurg Psychiatry ; 76(7): 992-5, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15965209

RESUMO

In this prospective double blind randomised "N of 1" study, a patient with a severe form of Tourette's syndrome was treated with bilateral high frequency stimulation of the centromedian-parafascicular complex (Ce-Pf) of the thalamus, the internal part of the globus pallidus (GPi), or both. Stimulation of either target improved tic severity by 70%, markedly ameliorated coprolalia, and eliminated self injuries. Severe forms of Tourette's syndrome may benefit from stimulation of neuronal circuits within the basal ganglia, thus confirming the role of the dysfunction of limbic striato-pallido-thalamo-cortical systems in this disorder.


Assuntos
Terapia por Estimulação Elétrica , Globo Pálido/fisiopatologia , Núcleos Intralaminares do Tálamo/fisiopatologia , Síndrome de Tourette/terapia , Adulto , Dominância Cerebral/fisiologia , Eletrodos Implantados , Feminino , Seguimentos , Humanos , Exame Neurológico , Estudos Prospectivos , Comportamento Autodestrutivo/fisiopatologia , Comportamento Autodestrutivo/terapia , Transtornos do Comportamento Social/fisiopatologia , Transtornos do Comportamento Social/terapia , Síndrome de Tourette/fisiopatologia
7.
Neurology ; 64(9): 1598-604, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15883323

RESUMO

BACKGROUND: High-frequency stimulation of the subthalamic nucleus (STN) is an effective treatment for advanced Parkinson disease (PD). The clinical and preoperative predictive factors of the best postoperative outcome have been identified. Radiologic predictive factors were investigated. METHODS: Forty patients with PD underwent surgery for bilateral STN stimulation. MRI was performed in stereotactic conditions before surgery. Brain parenchyma, caudate nucleus, putamen, pallidum, and red nucleus volumes and the surface of the mesencephalon were measured and normalized as percentages of the intracranial volume. Clinical evaluation was performed 1 month before and 6 months after surgery. RESULTS: The normalized brain parenchyma volume was lower in patients who were older and had a longer disease duration or a lower frontal score and was not predictive of the postoperative outcome. The residual scores for activities of daily living and parkinsonian motor disability were higher in patients with a smaller normalized mesencephalon. The normalized caudate nucleus volume was predictive of the pre- and postoperative levodopa-equivalent dosage. CONCLUSIONS: Brain atrophy is not an exclusion criterion for neurosurgery, indicating that patients' neurologic, psychiatric, and neuropsychological characteristics are the best predictive factors for neurosurgery. The fact that a smaller normalized mesencephalon surface was associated with a lower beneficial effect of the subthalamic nucleus stimulation on the parkinsonian motor disability suggests that the normalized mesencephalon surface is a predictive factor of the postoperative outcome.


Assuntos
Atrofia/patologia , Encéfalo/patologia , Estimulação Encefálica Profunda/normas , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/patologia , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiologia , Atividades Cotidianas , Idade de Início , Idoso , Antiparkinsonianos/administração & dosagem , Atrofia/etiologia , Atrofia/fisiopatologia , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Estimulação Encefálica Profunda/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Seleção de Pacientes , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Estatística como Assunto , Resultado do Tratamento
8.
Neurology ; 59(9): 1425-7, 2002 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-12427896

RESUMO

The authors report a patient with advanced PD, successfully treated by bilateral stimulation of the subthalamic nucleus, who developed acute transient aggressive behavior during intraoperative electrical test stimulation. The electrode responsible for this abnormal behavior was located within the lateral part of the posteromedial hypothalamic region (triangle of Sano). The authors suggest that affect can be dramatically modulated by the selective manipulation of deep brain structures.


Assuntos
Agressão , Terapia por Estimulação Elétrica/efeitos adversos , Hipotálamo Posterior/fisiologia , Complicações Intraoperatórias/etiologia , Doença de Parkinson/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/cirurgia
10.
J Neurol Neurosurg Psychiatry ; 72(6): 701-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12023409

RESUMO

OBJECTIVE: to analyse 24 parkinsonian patients successfully treated by bilateral STN stimulation for the presence of behavioural disorders. METHOD: patients were evaluated retrospectively for adjustment disorders (social adjustment scale, SAS), psychiatric disorders (comparison of the results of psychiatric interview and the mini international neuropsychiatric inventory) and personality changes (IOWA scale of personality changes). RESULTS: parkinsonian motor disability was improved by 69.5% and the levodopa equivalent daily dosage was reduced by 60.5%. Social adjustment (SAS) was considered good or excellent in nine patients, moderately (n=14), or severely (n=1) impaired in 15 patients. Psychiatric disorders consisted of amplification or decompensation of previously existing disorders that had sometimes passed unnoticed, such as depressive episodes (n=4), generalised anxiety (n=18), and behavioural disorders with drug dependence (n=2). Appearance of mild to moderate emotional hyperreactivity was reported in 15 patients. Personality traits (IOWA scale) were improved in eight patients, unchanged in seven, and aggravated in eight CONCLUSION: Improvement in parkinsonian motor disability induced by STN stimulation is not necessarily accompanied by improvement in psychic function and quality of life. Attention is drawn to the possible appearance of personality disorders and decompensation of previous psychiatric disorders in parkinsonian patients who are suitable candidates for neurosurgery. We suggest that a careful psychological and psychiatric interview be performed before surgery, and emphasise the need for psychological follow up to ensure the best possible outcome.


Assuntos
Terapia por Estimulação Elétrica , Transtornos das Habilidades Motoras/terapia , Doença de Parkinson/terapia , Comportamento Social , Núcleo Subtalâmico/fisiologia , Ansiedade/etiologia , Depressão/etiologia , Terapia por Estimulação Elétrica/efeitos adversos , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Transtornos das Habilidades Motoras/etiologia , Doença de Parkinson/patologia , Personalidade , Qualidade de Vida , Transtornos Relacionados ao Uso de Substâncias , Resultado do Tratamento
11.
J Neurol Neurosurg Psychiatry ; 72(4): 517-22, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11909914

RESUMO

OBJECTIVE: To describe a reversible neurological condition resembling a crossed midbrain syndrome resulting from high frequency stimulation (HFS) in the midbrain. METHODS: Postoperative evaluation of quadripolar electrodes implanted in the area of the subthalamic nucleus of 25 patients with Parkinson's disease (PD) successfully treated by HFS. RESULTS: Four of the 25 patients experienced reversible acute diplopia, with dystonic posture and tremor in the contralateral upper limb when the white matter between the red nucleus and the substantia nigra was stimulated. The motor signs resembled those caused by lesions of the red nucleus. The ipsilateral resting eye position was "in and down" (three patients) or "in" (one patient). Enophthalmos was seen. Abduction was impaired and vertical eye movements were limited, but adduction was spared. The movements of the controlateral eye were normal. The ocular signs could be best explained by sustained hyperactivity of the extrinsic oculomotor nerve. Simultaneous tonic contraction of the superior rectus, the inferior rectus, and inferior oblique may cause the enophthalmos and partial limitation of upward and downward eye movements. Antagonist tonic contraction of the ipsilateral medial rectus severely impairs abduction. CONCLUSION: This crossed midbrain syndrome, possibly resulting from simultaneous activation of oculomotor nerve and lesion-like inhibition of the red nucleus suggests that high frequency stimulation has opposite effects on grey and white matter.


Assuntos
Terapia por Estimulação Elétrica/efeitos adversos , Mesencéfalo/fisiologia , Nervo Oculomotor/fisiologia , Doença de Parkinson/terapia , Terapia por Estimulação Elétrica/métodos , Eletrodos , Movimentos Oculares/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Subtalâmico/fisiologia , Síndrome
12.
Brain ; 125(Pt 3): 575-83, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11872614

RESUMO

High-frequency stimulation of the subthalamic nucleus (STN) constitutes one of the most effective treatments for advanced forms of Parkinson's disease. The cost and potential risks of this procedure encourage the determination of clinical characteristics of patients that will have the best postoperative outcome. Forty-one Parkinson's disease patients underwent surgery for bilateral STN stimulation. The selection criteria were severe parkinsonian motor disability, clear response of symptoms to levodopa, occurrence of disabling levodopa-related motor complications and the absence of dementia and significant abnormalities on brain MRI. Clinical evaluation was performed 1 month before and 6 months after surgery. The improvement in the activities of daily living subscale of the Unified Parkinson's Disease Rating Scale, Part II (UPDRS II) and parkinsonian motor disability (UPDRS III) was greater when the preoperative scores for activities of daily living and parkinsonian motor disability, in particular axial symptoms, such as gait disorders and postural instability assessed at the time of maximal clinical improvement (on drug), were lower. Age and disease duration were not predictive, but parkinsonian motor disability tended to be more improved in patients with younger age and shorter disease duration. The severity of levodopa-related motor complications was not a predictive factor. The outcome of STN stimulation was excellent in levodopa-responsive forms of Parkinson's disease, i.e. in patients with selective brain dopaminergic lesions, and moderate in patients with axial motor symptoms and cognitive impairment known to be less responsive or unresponsive to levodopa treatment, i.e. when brain non-dopaminergic lesions develop in addition to the degeneration of the nigrostriatal dopaminergic system. The results are consistent with the classical inclusion criteria for STN stimulation, but imply that the decision to operate on the oldest patients and/or patients with gait and postural disorders, who are poorly responsive to levodopa, should be weighed carefully.


Assuntos
Doença de Parkinson/terapia , Núcleo Subtalâmico/cirurgia , Fatores Etários , Idade de Início , Idoso , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Causalidade , Progressão da Doença , Discinesia Induzida por Medicamentos/complicações , Terapia por Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Seleção de Pacientes , Valor Preditivo dos Testes , Núcleo Subtalâmico/fisiopatologia , Resultado do Tratamento
13.
Eur J Neurosci ; 14(3): 554-60, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11553305

RESUMO

Saccade adaptation can be experimentally induced by systematically displacing a visual cue during a targeting saccade. Non-human primate studies have highlighted the crucial role of the cerebellum for saccade adaptation, but its neural substrates in humans are poorly understood. Recent physiological experiments suggest that, in addition to cerebellar structures, cortical areas may be involved as well. We have therefore hypothesized that saccade adaptation may rely on a cerebello-cerebral network, in which the cerebellar thalamus may link cerebellar and cerebral structures. To test this hypothesis, we studied saccade adaptation in a group of four patients with a thalamic lesion, with (n = 2) or without (n = 2) involvement of the cerebellar thalamus. Compared to healthy subjects, saccade adaptation was reduced in patients with associated cerebellar syndrome, but normal in patients without cerebellar syndrome. These results are consistent with the hypothesis that cerebello-thalamic pathways contribute to saccade adaptation in humans and suggest that the thalamus relays adaptation-related information from the cerebellum to cerebral cortical oculomotor areas.


Assuntos
Adaptação Fisiológica/fisiologia , Cerebelo/fisiologia , Movimentos Sacádicos/fisiologia , Tálamo/fisiologia , Adulto , Idoso , Doenças Cerebelares/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiologia , Estimulação Luminosa , Doenças Talâmicas/fisiopatologia
14.
Am J Gastroenterol ; 96(2): 515-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11232699

RESUMO

OBJECTIVES: Focal neurological signs have been poorly documented in the course of hepatic encephalopathy in cirrhotic patients because they are not mentioned in any textbooks of liver diseases. Having the opportunity to observe such cases, we underwent a prospective study to determine incidence, characteristics, associated factors, prognostic significance, and outcome of this rare form of hepatic encephalopathy. METHODS: Over a 12-month period, all cirrhotic patients hospitalized in the intensive care unit of our department for hepatic encephalopathy were prospectively studied. Patients with clinical and electroencephalogram evidences of hepatic encephalopathy were examined by a senior physician and, in cases of focal neurological signs, underwent examination by a neurologist, CT scan, lumbar punction, and cerebral magnetic resonance imaging and echo Doppler examination of neck and head vessels. Clinical and biological parameters were compared in patients during episodes with and without focal neurological signs, and outcome was noted. RESULTS: Thirty-four cirrhotic patients were hospitalized for 48 episodes of hepatic encephalopathy; two of these patients with cerebral hematoma were excluded. Twenty-four patients exhibited 38 hepatic encephalopathy episodes without focal neurological signs (82.6%), and eight patients exhibited eight hepatic encephalopathy episodes with focal neurological signs (17.4%) that were hemiplegia and hemiparesia in six patients (75%). In all patients, cerebral CT scan and cerebrospinal fluid examination disclosed no abnormalities, as neither did cerebral magnetic resonance imaging (n = 5) and echo Doppler examination of neck and head vessels (n = 5). Except for female sex, which was more often encountered in patients with focal neurological signs (p < 0.05), there were no differences between episodes with and without focal neurological signs for any of the parameters studied. In surviving patients who recovered from hepatic encephalopathy (7/8), focal neurological signs disappeared without recurrences after follow up of 6 months (3-12). CONCLUSIONS: Hepatic encephalopathy with focal neurological signs when carefully searched is not uncommon. It could be more frequent in cirrhotic females, is reversible, and has no prognostic significance.


Assuntos
Hemiplegia/etiologia , Encefalopatia Hepática/complicações , Cirrose Hepática/complicações , Estudos de Casos e Controles , Feminino , Seguimentos , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/epidemiologia , Encefalopatia Hepática/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Prognóstico , Estudos Prospectivos , Fatores Sexuais , Fatores de Tempo
15.
Neuroscience ; 101(1): 77-87, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11068138

RESUMO

Our objective was to elaborate a functional map of the globus pallidus by correlating the intrapallidal localization of quadripolar electrodes implanted in parkinsonian patients with the clinical effect of the stimulation of each contact. Five patients with L-DOPA-responsive Parkinson's disease presenting severe motor fluctuations and L-DOPA-induced dyskinesias were treated by continuous bilateral high-frequency stimulation of the globus pallidus. The effects of stimulation on parkinsonian disability were tested through each of the four stimulating contacts of each electrode. The anatomical localization of each of the stimulating contacts was determined by confronting the pre- and post-operative magnetic resonance imaging with the anatomical atlas of Schaltenbrand and Wharen.(34) The registration procedure comprised digitization of the atlas, the use of deformation tools to fit atlas sections with magnetic resonance imaging sections, and three-dimensional reconstruction of both the atlas and the magnetic resonance imaging sections. Analysis of the 32 stimulating contacts tested did not reveal a somatotopic organization in the pallidal region investigated but demonstrated that high-frequency stimulation had contrasting effects depending on whether it was applied to the external or the internal pallidum. Akinesia was improved by stimulation of the external pallidum but worsened by stimulation of the internal pallidum. In contrast, parkinsonian rigidity was improved by stimulation of either part of the pallidum. The areas in the internal pallidum where stimulation worsened akinesia were those in which stimulation reduced or suppressed L-DOPA-induced dyskinesias. Conversely, stimulation applied to the external pallidum induced dyskinesias. The fact that rigidity was improved by stimulation of the internal and external pallidum suggests that the neuronal bases of parkinsonian rigidity are different from those of akinesia and dyskinesias. The effect on akinesia and dyskinesias is in agreement with the current model of basal ganglia circuitry(10) if high-frequency stimulation activates rather than inhibits pallidal neurons, a possibility which is very likely since there are marked anatomical, biochemical and electrophysiological differences between the globus pallidus and the subthalamic nucleus. This study demonstrates that high-frequency stimulation of the globus pallidus in parkinsonian patients has contrasting effects depending on whether it is applied to the external or the internal part of this nucleus. The effect on akinesia and dyskinesias suggests that stimulation activates pallidal neurons, a result which challenges the generally accepted concept that high-frequency stimulation inactivates neurons in the region stimulated.


Assuntos
Globo Pálido/fisiopatologia , Vias Neurais/fisiopatologia , Doença de Parkinson/terapia , Adulto , Idoso , Mapeamento Encefálico , Discinesias/patologia , Discinesias/fisiopatologia , Discinesias/terapia , Terapia por Estimulação Elétrica , Globo Pálido/patologia , Humanos , Pessoa de Meia-Idade , Vias Neurais/patologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Resultado do Tratamento
16.
Mov Disord ; 15(5): 919-24, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11009200

RESUMO

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.


Assuntos
Estimulação Elétrica/efeitos adversos , Mioclonia/etiologia , Doença de Parkinson/fisiopatologia , Tálamo/fisiopatologia , Tremor/etiologia , Núcleos Ventrais do Tálamo/fisiopatologia , Idoso , Braço , Eletrodos Implantados , Lateralidade Funcional , Humanos , Pessoa de Meia-Idade , Mioclonia/fisiopatologia , Doença de Parkinson/terapia , Tálamo/cirurgia , Tremor/fisiopatologia
17.
Neurology ; 55(5): 728-30, 2000 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-10980748

RESUMO

Bilateral high-frequency continuous stimulation of the internal globus pallidus or subthalamic nucleus constitutes a new therapeutic approach for the treatment of patients with severe PD. The authors report two patients in whom stimulation of the globus pallidus failed to give long-term relief and was successfully replaced by bilateral subthalamic stimulation. The results emphasize the reversibility of deep brain stimulation therapy and suggest that the subthalamic target is preferable to the pallidal target.


Assuntos
Globo Pálido/fisiopatologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiopatologia , Estimulação Elétrica , Feminino , Globo Pálido/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Fatores de Tempo
18.
J Neurosurg ; 92(4): 589-98, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10761647

RESUMO

OBJECT: The goal of this study was to determine the somatotopical structure-function relationships of the primary motor cortex in individual patients by using functional magnetic resonance (fMR) imaging. This was done to assess whether there is a displacement of functional areas compared with anatomical landmarks in patients harboring brain tumors close to the central region, and to validate these findings with intraoperative cortical stimulation. METHODS: One hundred twenty hemispheres in 60 patients were studied by obtaining blood oxygen level-dependent fMR images in patients while they performed movements of the foot, hand, and face on both sides. There was a good correspondence between anatomical landmarks in the deep portion of the central sulcus on axial slices and the somatotopical organization of primary motor areas. Pixels activated during hand movements were centered on a small characteristic digitation; those activated during movements in the face and foot areas were located in the lower portion of the central sulcus (lateral to the hand area) and around the termination of the central sulcus, respectively. In diseased hemispheres, signal-intensity changes were still observed in the projection of the expected anatomical area. The fMR imaging data mapped intraoperative electrical stimulation in 92% of positive sites. CONCLUSIONS: There was a high correspondence between the somatotopical anatomy and function in the central sulcus, which was similar in normal and diseased hemispheres. The fMR imaging and electrical stimulation data were highly concordant. These findings may enable the neurosurgeon to locate primary motor areas more easily during surgery.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Estimulação Elétrica , Imageamento por Ressonância Magnética , Monitorização Intraoperatória , Córtex Motor/fisiopatologia , Adulto , Idoso , Astrocitoma/patologia , Astrocitoma/fisiopatologia , Astrocitoma/cirurgia , Mapeamento Encefálico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Face/fisiologia , Pé/fisiologia , Mãos/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Córtex Motor/patologia , Oligodendroglioma/patologia , Oligodendroglioma/fisiopatologia , Oligodendroglioma/cirurgia , Oxigênio/sangue , Estudos Retrospectivos
19.
J Neurosurg ; 92(4): 615-25, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10761650

RESUMO

OBJECT: Several methods are used for stereotactically guided implantation of electrodes into the subthalamic nucleus (STN) for continuous high-frequency stimulation in the treatment of Parkinson's disease (PD). The authors present a stereotactic magnetic resonance (MR) method relying on three-dimensional (3D) T1-weighted images for surgical planning and multiplanar T2-weighted images for direct visualization of the STN, coupled with electrophysiological recording and stimulation guidance. METHODS: Twelve patients with advanced PD were enrolled in this study of bilateral STN implantation. Both STNs were visible as 3D ovoid biconvex hypointense structures located in the upper mesencephalon. The coordinates of the centers of the STNs were determined with reference to the patient's anterior commissure-posterior commissure line by using a new landmark, the anterior border of the red nucleus. Electrophysiological monitoring through five parallel tracks was performed simultaneously to define the functional target accurately. Microelectrode recording identified high-frequency, spontaneous, movement-related activity and tremor-related cells within the STNs. Acute STN macrostimulation improved contralateral rigidity and akinesia, suppressed tremor when present, and could induce dyskinesias. The central track, which was directed at the predetermined target by using MR imaging, was selected for implantation of 19 of 24 electrodes. No surgical complications were noted. CONCLUSIONS: At evaluation 6 months after surgery, continuous STN stimulation was shown to have improved parkinsonian motor disability by 64% and 78% in the "off' and "on" medication states, respectively. Antiparkinsonian drug treatment was reduced by 70% in 10 patients and withdrawn in two patients. The severity of levodopa-induced dyskinesias was reduced by 83% and motor fluctuations by 88%. Continuous high-frequency stimulation of the STN applied through electrodes implanted with the aid of 3D MR imaging and electrophysiological guidance is a safe and effective therapy for patients suffering from severe, advanced levodopa-responsive PD.


Assuntos
Terapia por Estimulação Elétrica/métodos , Eletroencefalografia , Imageamento por Ressonância Magnética , Doença de Parkinson/terapia , Radiologia Intervencionista , Técnicas Estereotáxicas , Núcleo Subtalâmico , Idoso , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Discinesia Induzida por Medicamentos/prevenção & controle , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados , Feminino , Seguimentos , Humanos , Levodopa/efeitos adversos , Masculino , Mesencéfalo/patologia , Pessoa de Meia-Idade , Monitorização Intraoperatória , Movimento , Doença de Parkinson/tratamento farmacológico , Planejamento de Assistência ao Paciente , Núcleo Rubro/patologia , Segurança , Núcleo Subtalâmico/patologia , Tremor/fisiopatologia , Tremor/terapia
20.
Arch Neurol ; 57(4): 461-5, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10768618

RESUMO

BACKGROUND: High-frequency stimulation of the subthalamic nucleus constitutes a therapeutic advance for severely disabled patients with Parkinson disease. OBJECTIVE: To evaluate the efficacy and safety of continuous bilateral high-frequency stimulation of the subthalamic nucleus in patients with Parkinson disease. DESIGN: A prospective study of patients with Parkinson disease treated at a university hospital. PATIENTS AND METHODS: Electrodes were implanted bilaterally in the subthalamic nucleus of 23 consecutive patients with Parkinson disease who responded well to levodopa but had severe motor complications. There were 16 men and 7 women (mean +/- SEM age, 53 +/- 2 years) who had a mean +/- SEM disease duration of 14.7 +/- 1.0 years. Targets were determined by 3-dimensional magnetic resonance imaging, combined with intraoperative electrophysiologic recordings and stimulation. RESULTS: Six months after surgery, motor disability, levodopa-induced motor fluctuations, dyskinesias, and the daily dose of levodopa equivalent decreased significantly by 67%, 78%, 77%, and 61%, respectively, compared with the preoperative state. No significant morbidity was observed, except transient depression in 4 patients. CONCLUSIONS: The beneficial effects of subthalamic stimulation depend on (1) the criteria used for patient selection, (2) the precision with which the subthalamic nucleus is targeted (dependent on the 3-dimensional magnetic resonance imaging and the intraoperative electrophysiologic and clinical assessments), and (3) the long-term postoperative adjustment of stimulation variables.


Assuntos
Terapia por Estimulação Elétrica/métodos , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiopatologia , Núcleo Subtalâmico/cirurgia , Atividades Cotidianas , Terapia por Estimulação Elétrica/efeitos adversos , Eletrodos Implantados , Feminino , Humanos , Levodopa/efeitos adversos , Levodopa/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/cirurgia , Estudos Prospectivos , Perfil de Impacto da Doença , Técnicas Estereotáxicas , Resultado do Tratamento
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