ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Abstract:The case of an elderly female with Parkinson's disease and severe refractory dyskinesias induced by medication is presented. The patient underwent surgical treatment with pallidotomy resulting in significant improvement in symptoms and quality of life. The indications for surgery, technique, and follow up are described.

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Abstract:During stereotaxy in nonanesthetized patients with Parkinson's disease or essential tremor, tremor was suppressed by test stimulation of the thalamic ventralis intermedius nucleus (Vim) at high frequency (130 Hz). Based on this finding, the authors have used chronic stimulation of the Vim as a permanent treatment of tremor for the past 10 years in 134 patients with movement disorders (Parkinson's disease, 91; essential tremor, 23; various dyskinesias and dystonias, 20). Based on experimental data, this method has been extended in the past 4 years to two other targets, the subthalamic nucleus (STN) (51 patients) and the internal pallidum (GPi) (12 patients). Stereotactically implanted chronic electrodes were connected to a programmable stimulator. Results depended on the indication and on the target. Parkinson's disease was the best indication, and, depending on the accurate placement of the electrode, tremor was totally controlled by Vim stimulation (which has no effect on akinesia and rigidity) in 85% of patients. Stimulation of the GPi was extremely effective on levodopa-induced dyskinesias but only moderately effective on the other symptoms. Stimulation of the STN, however, controlled all three symptoms and allowed the decrease or suppression of levodopa, which then alleviated dyskinesias. In other types of movement disorders, including dystonia, these targets were not thoroughly evaluated for deep brain stimulation. The stimulation of any of the three targets induced minor side effects, which were well tolerated, adjustable, and immediately reversible. There was no operative mortality, and permanent morbidity was observed in 3 of 197 patients, including all targets. The mechanisms of action of stimulation are not fully understood and are probably different depending on the target. In all cases, however, inhibition of cellular activity or of neural network function could be induced by jamming a retroactive loop in the Vim or by shutting down neurotransmitter release in the STN and the GPi. Mechanisms within the same target also are probably different for suppression of tremor or other symptoms. Chronic stimulation of these three targets, which is reversible, adaptable, and well tolerated even in bilaterally operated (119 of 197) and elderly patients, has been validated by several years' use in hundreds of patients around the world and should replace ablative methods in the regular surgical treatment of Parkinson's disease and essential tremor. The low rate of permanent complications, the minor side effects (when any) and their immediate reversibility, the possibility of bilateral implantation in the same session, and the long-term persistence of symptom relief support the use of chronic stimulation of the Vim, the STN, or the GPi when surgery is indicated for the treatment of Parkinson's disease and essential tremor, and even more so when a bilateral procedure is necessary. STN stimulation, however, is likely to become the first choice because of its efficacy in treating all major symptoms of Parkinson's disease.

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Abstract:Pallidotomy, the surgical destruction of portions of the globus pallidus, is now frequently performed to treat patients with Parkinson's disease. As a consequence of dopamine loss in the brain of a patient with Parkinson's disease, the globus pallidus internal segment (GPi) is overactive. A lesion in the GPi compensates for this and partially alleviates most of the motor signs of Parkinson's disease, as well as levodopa-induced dyskinesias. The goal in pallidotomy is to produce a lesion of the whole sensorimotor (posterolateral) region of the GPi without producing a lesion in the external pallidum, nonmotor areas of the GPi, optic tract, or corticospinal tract. To achieve this goal, magnetic resonance imaging (MRI)-based stereotactic localization, microelectrode recording, and macrostimulation are used in concert for precise localization of the GPi and surrounding structures. Based on the known patterns of neuronal activity and receptive fields in the basal ganglia, microelectrode recording is used to construct a detailed three-dimensional map of the GPi and to identify the motor-controlling subdivision of this nucleus. Multiple microelectrode tracks, rather than a single track, are used to maximize accuracy. Pallidotomy is performed with a radiofrequency thermocoagulation probe, at multiple depths along multiple parallel tracks, to contour the lesion according to the microelectrode derived map. Precise lesion placement is important for the best long-term outcome.

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Abstract:The historical development of the use of microelectrode recording to guide functional stereotactic procedures is briefly reviewed and the technique described in detail as used during pallidal or thalamic surgery for movement disorders.

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Abstract:Thalamotomy is the procedure in functional stereotactic neurosurgery that has the longest continuous track record, a better-defined target site, or more information about clinical outcomes. It has evolved with and been influenced by new neuroscientific knowledge and technologies: thalamic anatomy and physiology, microelectrode recording, electrical stimulation and evoked potentials, computerized tomography and magnetic resonance imaging, and even focused radiation. Depsite the controversy regarding what combination of techniques is necessary to obtain the best clinical outcomes, there is agreement that in properly selected patients with disabling, refractory tremor, thalamotomy can provide excellent long-term tremor control. The technique used by the authors and the rationale for using thalamotomy is described in detail.

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Abstract:Parkinson's disease is characterized by loss of dopaminergic neurons in the substantia nigra that innervate the caudate and putamen. Primate and rodent models indicate that, after transplantation, fetal mesencephalic tissue is capable of surviving and establishing synaptic reconnectivity with subsequent functional neurologic improvement. Since the late 1980s, fetal tissue transplantation has been performed at selected centers in the United States. This article focuses on patient selection, fetal tissue viability, surgical technique, and postoperative management for patients undergoing fetal tissue transplantation for treatment of Parkinson's disease.

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1077-2855    

出版商:OVID    

年代:1999

数据来源: OVID