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The
Functional and Stereotactic Neurosurgery Center provides comprehensive
evaluation and care for patients with movement disorders, epilepsy, obsessive-compulsive
disorder, and certain chronic pain syndromes. The center works closely
with the Partners
Parkinson and Movement Disorders Treatment Center, and the MGH
Epilepsy Unit. |
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Pallidotomy Bibliography
Referrals
| Stereotactic Surgery | Parkinson's
Disease | Intractable
Epilepsy | Movement Disorder
Surgery
09136035 95066035 Pharmacotherapy with levodopa for Parkinson's disease provides symptomatic benefit, but fluctuations in (or loss of) response may eventually occur. Dopamine agonists are also helpful and, when taken with low doses of levodopa, often provide sustained benefit with fewer side effects; novel agonists and new methods for their administration are therefore under study. Other therapeutic strategies are being explored, including the use of type B monoamine oxidase inhibitors to reduce the metabolic breakdown of dopamine, catechol-O-methyltransferase inhibitors to retard the breakdown of levodopa, norepinephrine precursors to compensate for deficiency of this neurotransmitter, glutamate antagonists to counteract the effects of the subthalamic nucleus, and various neurotrophic factors to influence dopaminergic nigrostriatal cells. Surgical procedures involving pallidotomy are sometimes helpful. Those involving cerebral transplantation of adrenal medullary or fetal mesencephalic tissue have yielded mixed results; benefits may relate to the presence of growth factors in the transplanted tissue. The transplantation of genetically engineered cell lines will probably become the optimal transplantation procedure. The cause of Parkinson's disease may relate to oxidant stress and the generation of free radicals. It is not clear whether treatment with selegiline hydrochloride (a type B monoamine oxidase inhibitor) delays the progression of Parkinson's disease, because the drug also exerts a mild symptomatic effect. Daily treatment with vitamin E (a scavenger of free radicals) does not influence disease progression, perhaps because of limited penetration into the brain. (57 Refs.)
09109958 95039958 This article reviews new medical and surgical treatments for Parkinson's disease (PD). Catechol-O-methyl-transferase (COMT) inhibitors supplement the variety of antiparkinsonian drugs interacting with the dopaminergic system. Clinical studies show that COMT inhibitors prolong the action of levodopa in patients with the "wearing off" phenomenon. The atypical antipsychotic drug clozapine is the treatment of choice for the alleviation of levodopa-induced psychosis. Clozapine also has beneficial effects on tremor and levodopa-induced dyskinesias. Thus, COMT inhibitors and clozapine provide new opportunities for the treatment of patients with longstanding PD and fluctuating responses to levodopa. Experimental evidence in animals suggests that glutamate antagonists have symptomatic and neuroprotective actions in PD. At present, however, only weak antiglutamatergic drugs that have low specificity, such as memantine, amantadine, and budipine are available for clinical studies. Neurotrophic factors, in particular ciliary neurotrophic factor and glial cell line-derived neurotrophic factor, are among the most promising new approaches for neuroprotection in PD. Problems of bioavailability, however, thus far preclude their use in patients. An improved understanding of the pathophysiology of parkinsonism has led to a renaissance of stereotaxic surgery. The subthalamic nucleus is a potential new target for surgical intervention. Ventroposterior pallidotomy has been shown to improve not only rigidity and tremor, but also akinesia. The techniques for thalamic interventions have been refined by introducing chronic thalamic stimulation. Future transplantation approaches to PD will focus on the use of genetically modified cells carrying genes for dopamine-synthesizing enzymes or neurotrophic factors. Animal studies show the feasibility of in vivo gene transfer for the treatment of PD. (53 Refs.)
09100649 95030649 Fetal graft research and renewed interest in Leksell's postero-ventral pallidotomy (PVP) stimulated reconsideration of surgical therapy for Parkinson's disease (PD), particularly with regard to improving akinetic symptoms previously thought resistant to surgical lesions. Review of our series and other published results of PVP and fetal graft show that PVP has beneficial effects on both akinetic and hyperkinetic symptoms that better the results reported for fetal graft implantation and other conventional stereotactics. Presented are the results of 60 consecutive patients, 55 of whom underwent PVP, and 5 who underwent fetal graft implantation. Using the Unified Parkinson's Disease Rating Scale (UPDRS), we found that PVP gave significant (P < 0.05) reductions in akinetic symptomatology including freezing, arising from a chair, posture, gait, postural instability, and bradykinesia. Fetal graft patients had significant reductions in two akinetic symptoms: bradykinesia and postural instability. PVP's dramatic therapeutic effects on akinesia may be explained by interruption of amplified collateral inhibitory output from the pallidum to brain stem locomotor centers such as the pedunculopontine nucleus, whereas interruption of collaterals to ventral lateral thalamus by PVP may account for the elimination of hyperkinesia. The excellent results of PVP represent a significant advance in the surgical treatment of PD. (33 Refs.)
08845021 94160021 The Leksell Gamma Knife is a useful and safe method to perform thalamotomy and pallidotomy in selected older patients with Parkinson's disease and related movement disorders. In this preliminary report, 2 of 3 patients with severe intention tremor were relieved of their symptoms by thalamotomy, as were 4 of 7 patients with Parkinson's tremor. Four of 8 patients had significant improvement of contralateral rigidity following pallidotomy.
08818819 94133819
08789104 94104104 Surgical treatment for Parkinson's disease began by blocking of the pyramidal system in early part of this era. In 1942, Meyers performed Ansotomy for the treatment of Parkinsonism without leaving hemiplegia, leading subsequent operating target to blocking of pallidofugal fiber. Then, the development of stereotaxy in 1947 caused an operative progress to Pallidotomy and further to Thalamotomy. Although the spread of levodopa therapy gradually brought about decline of surgical treatment, Thalamotomy became to be reexamined in view of not a little problems about and side effects of levodopa therapy. With the development of CT, MRI and the like, Thalamotomy via MRI-stereotaxy was developed, making operations safer and surer. Besides, transplantation of dopamine neurons into the striatum was tried as an essential treatment and is in clinical application via animal experiments. Fetal ventral mesencephalic tissue and adrenal medullary tissue are available therefore, but demerits are such that the former poses some ethical problem and the latter is poor and short-lived response. The transplantation of stellate ganglion into the striatum, which we have recently developed is safe and more effective than the adrenal medullary tissue. The respective one thirds of the cases did without levodopa following transplantation, needed half as much as the preoperative levodopa dose and needed the same as the latter. Although Horner's syndrome was noted in all cases following transplantation, no Parkinson syndrome became aggravated in any one of the cases. (15 Refs.)
08573757 93283757 Neurosurgical attempts to correct parkinsonism use strategies aimed either at alleviating the underlying dopamine deficiency or at correcting abnormal compensatory effects in neural circuits within the basal ganglia. During the review period, clinical trials of four different neurosurgical approaches were reported. These approaches are intracerebral transplantation of fetal dopamine neurons, intracerebral transplantation of adrenal medullary tissue, tremor-reducing surgical lesions in the ventrolateral thalamus, and ventroposterior pallidotomy aimed at reducing akinesia and rigidity. Experimental studies in rats and monkeys designed to explore mechanisms of graft actions were also reported. (33 Refs.)
08430974 93140974 Based on recent neuroanatomic and physiologic discoveries, neurosurgical therapies may increasingly complement and extend pharmacologic management of Parkinson's disease. Procedures showing promise include subthalamotomy and pallidotomy; thalamic electrical stimulation may also offer application for tremor control. Transplantation of adrenal chromaffin cells has not been associated with consistent long-term improvement in most patients, and fetal mesencephalic transplantation remains controversial. Trophic factors that may be pivotal to cellular repair and survival of transplanted tissue have potential therapeutic roles when purified and perfused centrally or when the cells that produce the factors are transplanted. (92 Refs.)
08357680 93067680 Stereotactic ventroposterolateral pallidotomy in 46 parkinsonian patients resulted in a complete or almost complete and long-lasting relief of rigidity and hypokinesia in 91% of the patients. Good tremor effect was obtained in 80% of them. The L-dopa-induced dyskinesias, gait and speech improved in most patients. Complications were observed in 7 cases after 51 pallidotomies, i.e. 14% (partial homonymous hemianopia in 6 and transient dysphasia and facial weakness in 1). We believe that the good effect of surgery is based on interruption of some striopallidal or subthalamopallidal pathways.
08238679 92376679 Hyperkinetic movement disorders may develop as a complication of stereotactic thalamotomy or pallidotomy. However, such movement disorders are uncommon after nonsterotactic intracranial operations. The authors report three cases of involuntary movement disorders unexpectedly developing after intracranial operations. The patients had undergone clipping of an internal carotid aneurysm, removal of an intracerebral hematoma, and resection of a tentorial meningioma. Two patients developed choreic movements and a dystonic posture of the unilateral upper extremity. One patient showed a tremor that had features of both parkinsonism and essential tremor. The symptoms of these patients were medically uncontrollable, and they were successfully treated with stereotactic ventrolateral thalamotomy.
07941042 92079042 Between 1985 and 1990, the authors performed stereotactic posteroventral pallidotomies on 38 patients with Parkinson's disease whose main complaint was hypokinesia. Upon re-examination 2 to 71 months after surgery (mean 28 months), complete or almost complete relief of rigidity and hypokinesia was observed in 92% of the patients. Of the 32 patients who before surgery also suffered from tremor, 26 (81%) had complete or almost complete relief of tremor. The L-dopa-induced dyskinesias and muscle pain had greatly improved or disappeared in most patients, and gait and speech volume also showed remarkable improvement. Complications were observed in seven patients: six had a permanent partial homonymous hemianopsia (one also had transient dysphasia and facial weakness) and one developed transitory hemiparesis 1 week after pallidotomy. The results presented here confirm the 1960 findings of Svennilson, et al., that parkinsonian tremor, rigidity, and hypokinesia can be effectively abolished by posteroventral pallidotomy, an approach developed in 1956 and 1957 by Lars Leksell. The positive effect of posteroventral pallidotomy is believed to be based on the interruption of some striopallidal or subthalamopallidal pathways, which results in disinhibition of medial pallidal activity necessary for movement control.
07661491 91180491 Fourteen thalamotomies and five pallidotomies were performed in 19 patients with hereditary intention tremor or Parkinson's disease. The target coordinates were determined by a stereotactic computed tomography study using the Laitinen noninvasive stereoadapter. Surgery was done without ventriculography. The patients were assessed 3-12 months later. In a postoperative stereotactic computed tomography study, the positions of the thalamic and pallidal targets were marked, and the coordinates of the center of the lesion were measured in relation to these targets. The volume of the lesion was calculated. In 3 thalamic lesion patients, no lesion could be visualized. The size of the eleven visible thalamic lesions ranged from 4 to 75 mm3 (mean 26), and the size of the 5 pallidal lesions ranged from 28 to 150 mm3 (mean 67). On the average, the center of the lesion was 1.4 mm medial to the position of the anatomical target (p less than 0.002). Neither size nor site of the lesion correlated with the clinical outcome.
05993434 86294434 The results of stereotactic pallidotomy in 37 patients with extrapyramidal disorders are presented. All patients had the same RF lesions and target coordinates. The patients are classified into 5 groups according to the clinical picture. These results are compared with those obtained by thalamotomy in a similar group of patients. The main indications for pallidotomy are given. The spatial representation of globus pallidus medialis according to Andrews and Watkins, Talairach and the author are shown and their differences discussed.
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