Combined Unilateral Radiofrequency Lesioning of the Motor Thalamus, Field of Forel, and Zona Incerta: A Series of Cases With Dystonia.

BACKGROUND: Dystonia is a group of disorders characterized by involuntary slow repetitive twisting movements and/or abnormal posture. Surgical options such as neuromodulation through deep brain stimulation and neuroablative procedures are available for patients who do not respond to conservative treatment. OBJECTIVE: To present our series of patients with dystonia who were treated with stereotactic combined unilateral radiofrequency lesioning of the motor thalamus, field of Forel, and zona incerta. METHODS: Medical records of 50 patients with dystonia who were treated with unilateral combined lesions were reviewed. Outcomes of the surgical procedure were evaluated using the Burke-Fahn-Marsden Dystonia Rating Scale (with movement and disability subscales) and Unified Parkinson's Disease Rating Scale-tremor items. RESULTS: Based on the symptoms, patients were categorized as having generalized dystonia (34%), hemidystonia (30%), and dystonic tremor (DT) (36%). Primary/idiopathic dystonia, primary genetic/hereditary dystonia, and secondary dystonia accounted for 16%, 4%, and 80% of patients, respectively. The mean follow-up duration was 156.2 ± 88.9 mo. The overall improvement in the Burke-Fahn-Marsden Dystonia Rating Scale scores (movement and disability, respectively) was 57.8% and 36.4% in generalized dystonia, 60.0% and 45.8% in hemidystonia, and 65.6% and 56.8% in DT. Patients with DT showed an 83.3% improvement in mean Unified Parkinson's Disease Rating Scale tremor score. Patients with cerebral palsy showed mean improvements of 66.7% in movement scores and 50.8% in disability scores. No mortality or major morbidity was observed postoperatively. CONCLUSION: Stereotactic radiofrequency unilateral combined thalamotomy, campotomy, and zona incerta lesions may be an effective surgical alternative for patients with dystonia, especially those with secondary dystonia resistant to deep brain stimulation.

Improvement of Table Tennis Dystonia by Stereotactic Ventro-Oral Thalamotomy: A Case Report.

BACKGROUND: Task-specific focal dystonia, such as writer's cramp and musician's cramp, is a type of dystonia that affects performance of particular tasks. Such movement disorders have been treated with stereotactic ventro-oral (Vo) thalamotomy with excellent outcomes. However, there has been no previous report of treatment of sport-related or athlete's dystonia by means of stereotactic surgery. We treated a patient with table tennis-related dystonia with Vo thalamotomy, and evaluated the outcome. CASE DESCRIPTION: A 20-year-old, female, left-handed table tennis player complained of difficulty hitting a ping-pong ball. She started playing table tennis at 8 years of age, practiced for more than 4 hours every day, and participated in national tournaments. Abnormal flexion of the left wrist when hitting a ball became apparent when she was 19 years old. The abnormal movement emerged on the forehand stroke and, subsequently, on the backhand, until finally she could not continue playing. The diagnosis was task-specific focal dystonia that did not recover with medication. She visited our hospital and underwent right Vo thalamotomy. The surgery was performed using local anesthesia, with the patient swinging a paddle during stimulation and coagulation of the thalamus. Her symptoms had improved completely the day after surgery, such that she was able to participate in tournaments again. CONCLUSIONS: We applied Vo thalamotomy for the successful treatment of athlete's dystonia, suggesting that this condition has an underlying mechanism similar to that of other task-specific focal dystonias. This provides new hope to patients with athlete's dystonia refractive to other therapies.

Dystonia and tremor secondary to thalamic infarction successfully treated with thalamotomy of the ventralis intermedius nucleus.

BACKGROUND: Focal thalamic lesions have been associated with a variety of involuntary movements such as tremor, dystonia, and chorea-ballism. METHODS: We describe a patient with severe hyperkinesias of the right arm secondary to a thalamic infarction in the left postero-ventral region of the thalamus. RESULTS: The dystonia and tremor of the right upper limb were subsequently controlled with another surgical lesion of the ventralis intermedius nucleus of the thalamus. CONCLUSION: This observation suggests that ablative surgery might be applied to treat a movement disorder induced by the lesion of the same nucleus, which in addition lead to interesting pathophysiological conjectures.

The neurosurgical treatment of patients in dystonic state - overview of the literature.

Treatment options for patients in dystonic state include sedation, artificial ventilation, intrathecal baclofen infusions and stereotactic procedures. The main aim of this overview is the presentation and assessment of stereotactic procedures applied for treating patients in severe dystonic state. We performed literature overview starting from 1998 to 2012 with case reports regarding all patients treated by stereotactic procedures for dystonic state. We were able to find 15 articles describing 22 patients. Ablative procedures were described in 5 articles (3 thalamotomies, 3 pallidotomies) and were done in 6 patients. In the remaining 10 articles, globus pallidus internus stimulation was utilized in another 16 patients. We can conclude that bilateral pallidal deep brain stimulation seems to be the best stereotactic target for patients in dystonic state.

[Role of neurosurgical management in movement disorders other than Parkinson disease].

Neurosurgical procedures are indispensable in management of various types of movement disorders (MD). Stereotactic operations that have been well established include deep brain stimulation for tremor, dystonia, and Parkinsonian symptoms. Recently the actual role of stereotactic ablative procedures such as thalamotomy and pallidotomy has been re-explored, and Vo thalamotomy shows long-term improvement of task specific focal dystonia like writer's cramp and musician's dystonia. A new less invasive treatment of tremor using MR guided focused ultrasound has started and is promising. Intrathecal administration of baclofen is also an established treatment for severe spasticity, but other ablative procedures such as peripheral neurotomy and dorsal rhizotomy are also important in spasticity treatment. It seems that most neurologists are unfamiliar, at least in Japan, with such neurosurgical procedures. However, neurologists involved in management of MD should understand the important roles of neurosurgical management of intractable MD and should refer such patients to appropriate neurosurgeons before permanent contracture and deformity develop.

[Neurosurgical management of dystonias].

Neurosurgical treatment, especially deep brain stimulation (DBS) of globus pallidum interna (GPi), is known to play a very important role in management of dystonia. GPi DBS is generally used for treatment of generalized and segmental dystonias and its efficacy is well established. However, the role of neurosurgical treatment for focal dystonia, especially task-specific focal hand dystonia (TSFHD), is not widely known. Writer's cramp (WC) and occupational cramp like musician's cramp (MC) belong to this category. I have treated more than 100 patients with TSFHD with modern stereotactic thalamotomy of the nucleus ventro-oralis (Vo). The dystonic symptoms immediately improved after making a small thermo-controlled lesioning in the Vo nucleus of the thalamus. There were no permanent complications. Stereotactic Vo thalamotomy is effective and safe for of task-specific focal hand dystonia. 25 years have passed after introduction of modern DBS, and now I think it time to discuss pros and cons of DBS and lesioning humbly and seriously. Not only DBS but thalamotomy and other neurosurgical procedures play an important role in management of dystonias.

[Surgical complications of deep brain stimulation: clinical experience of 184 cases]. / Complications chirurgicales de la stimulation cérébrale profonde : expérience clinique à propos de 184 cas.

BACKGROUND AND PURPOSE: Deep brain stimulation (DBS) is an effective treatment of movement disorders and psychiatric diseases. However, this surgery is still time consuming and associated with complications, among which we aimed to identify non-stimulo-induced adverse effects. Hence, we retrospectively systematically analyzed patients operated on, at our institution, using magnetic resonance imaging (MRI) direct anatomic mapping. METHODS: One hundred and seventy-five patients (184 surgeries) were performed between 1994 and 2008, for Parkinson's disease, essential tremor, dystonia and obsessive compulsive disorder. Primary anatomic targets were the subthalamic region, the intern pallidum and the thalamus. Final electrode positioning was adjusted according to intraoperative neuron recordings and acute stimulation tests. All surgically related adverse effects were collected. Life threatening or new non-planed surgery was considered as severe adverse effects. RESULTS: Adverse effects occurred 10 times (5.4%) during MRI acquisition, 24 times (13%) with five serious (2.7%) including one1 death (0.5%) during electrodes implantation and 17 times (9.2%) with four serious (2.2%) during neuropacemaker implantation. Electrodes were repositioned in six cases (five patients, n=3.4%). CONCLUSION: DBS efficiency is recognized however the significant incidence of adverse effects should prompt us to improve the procedures.

[Stereotactic radiosurgery for movement disorders]. / Stereotaktyczna radiochirurgia w leczeniu chorób ruchu.

Nowadays, functional neurosurgery is an established treatment for movement disorders such as Parkinson's disease, essential tremor, and dystonia. The effectiveness and safety of neuromodulation procedures (deep brain stimulation) replaced in the last years ablative irreversible stereotactic lesions for movement disorders. Stereotactic radiosurgery with gamma knife is a non-invasive form of treatment for movement disorders. The main limitation of stereotactic radiosurgery is the impossibility of electrophysiological confirmation of the target structure. Nevertheless, patients with advanced age and significant medical conditions that preclude classic open stereotactic procedures or patients who must receive anticoagulation therapy may gain great functional benefit using gamma knife stereotactic radiosurgery.

Destructive stereotactic surgery for treatment of dystonia.

BACKGROUND: This study is a retrospective review of the results of stereotactic destructive surgery in selected cases of drug-resistant dystonia. METHODS: Fifty-eight patients with drug-resistant dystonia were treated with stereotactic surgery between 1991 and 1999 in our institution. These patients' charts were retrospectively analyzed. The timing of the conducted evaluations was as follows: preoperatively, postoperatively, in the postoperative 1st week, 6th month, 12th month, and also thereafter every year. RESULTS: Symptoms of dystonia occurred before the age of 10 years in 30 patients (51.8%) and after the age of 10 years in 28 patients (48.2%). Generalized dystonia was detected in 41 patients, whereas 11 patients had hemidystonia, 5 patients had focal dystonia, and 1 patient had segmental dystonia. The most common etiologic factor was CP (n = 34). A total of 103 ablative lesions were created in 86 surgical sessions. Thalamotomy, pallidotomy, subthalamotomy, and the region of Forel lesions were performed either separately or in combination. In this series, the mean follow-up time was 102.2 months. Except for 2 cases of temporary hemiparesis, no other complications were observed. Minor improvement was obtained in 17 patients (19.7%), improvement of a medium degree was obtained in 17 patients (19.7%), high-degree improvement was obtained in 11 (12.8%), and very high degree improvement was obtained in 16 (18.6%) patients. A final evaluation revealed permanent improvement in 32 patients (55.2%). CONCLUSION: Production of stereotactic destructive lesions in certain specified targets is a safe method that improves quality of life and aids ambulation in patients with dystonia resistant to medical therapy.

Neuronal activity in the basal ganglia and thalamus in patients with dystonia.

OBJECTIVE: To explore the role of abnormal neuronal activity in the basal ganglia and thalamus in the generation of dystonia. METHODS: Microelectrode recording was performed in the globus pallidus internus (GPi), ventral thalamic nuclear group ventral oral posterior/ventral intermediate, Vop/Vim) and subthalamic nucleus (STN) in patients with primary dystonia (n=11) or secondary dystonia (n=9) during surgery. Electromyogram (EMG) was simultaneously recorded in selected muscle groups. Single unit analysis and cross-correlations were carried out. RESULTS: Three hundred and sixty-seven neurons were obtained from 29 trajectories (GPi: 13; Vop/Vim: 12; STN: 4), 87% exhibited altered neuronal activity including grouped discharges in GPi (n=79) and STN (n=37), long-lasting neuronal activity (n=70) and rapid neuronal discharge (n=86) in Vop/Vim. There were neurons in Vop, GPi and STN firing at the same frequency as EMG during dystonia (mean: 0.39 Hz, range 0.12-0.84 Hz). Significant correlations between neuronal activity and EMG at the frequency of dystonia were obtained (GPi: r2=0.7 (n=31), Vop/Vim: r2=0.64 (n=18) and STN: r2=0.86 (n=17)). CONCLUSIONS: Consistent with previous findings of abnormalities observed in Vop/VIM and GPi in relation to dystonia, the present data further show that the altered activity in GPi, specifically in dorsal subregions of GPi, Vop/Vim and STN is likely to be directly involved in the production of dystonic movement. Dystonia-related neuronal activity observed in motor thalamus and basal ganglia nuclei of GPi and STN indicates a critical role of their interactions affecting both indirect and direct pathways in the development of either generalized or focal dystonia. SIGNIFICANCE: These data support a central role of the basal ganglia in producing dystonic movements.

Deep brain stimulation for dystonia confirming a somatotopic organization in the globus pallidus internus.

OBJECT: In patients with dystonia, symptoms vary greatly in their extent and severity. The efficacy of pallidal stimulation is now established, but an interindividual variability in the responses to this treatment exists. A retrospective analysis of postoperative magnetic resonance (MR) images demonstrated millimetric variations in the positions of electrode contacts inside the posterolateroventral portion of the globus pallidus internus (GPi). It therefore seemed very likely that there is a somatotopic organization within the GPi. The goal of this study was to examine the positions of specific electrode contacts according to patients' clinical evolution, so that a somatotopic organization within the GPi could be defined. METHODS: This study included 19 patients (17 of whom were right handed) with generalized dystonia who were treated by bilateral stimulation of the GPi. Patients were examined pre- and postoperatively by using the Burke-Fahn-Marsden Dystonia Rating Scale. Dividing the patient's body into three parts--cervicoaxial area, superior limb, and inferior limb--we determined the following: 1) where the dystonic symptoms started; 2) where symptoms predominated at the time of surgery; and 3) where the highest postoperative improvement was observed. Variations in clinical response were correlated to the positions of the electrode contacts. All activated electrode contacts were in the posterolateroventral portion of the GPi (Laitinen target). A correlation between the contact location measured longitudinally and the part of the body in which the highest improvement was observed (three different areas; p = 0.004) showed that a location more anterior for the inferior limb and one more posterior for the superior limb were delineated for the right side, but not for the left side. CONCLUSIONS: Inside the posterolateroventral subvolume of the GPi on the right side, three statistically different locations of electrode contacts were determined to be primary deep brain stimulation treatment sites for particular body parts in cases of dystonia.

Neurosurgical treatment of spasticity and other pediatric movement disorders.

For children whose spasticity and movement disorders are inadequately treated by oral medications and botulinum toxins, neurosurgical procedures are now available to effectively treat spasticity, tremor, and many cases of dystonia. Spastic diplegia can be treated with selective lumbar rhizotomies, which significantly decrease spasticity, increase range of motion, and improve Gross Motor Function Measure scores. Children with spastic quadriparesis and those with secondary dystonia can be treated with intrathecal baclofen, which diminishes both spasticity and dystonia and is associated with improved function and quality of life. Children with primary dystonia and those with tremor can be treated with deep brain stimulation of the internal globus pallidus and thalamus, respectively. Some children with chorea respond to deep brain stimulation. There are no effective neurosurgical treatments for athetosis or ataxia. The effectiveness of neurosurgical treatments of pediatric movement disorders has increased significantly in the past 15 years.

Surgical therapy for dystonia.

Surgical treatments for dystonia have been available since the early 20th century, but have improved in their efficacy to adversity ratio through a combination of technologic advances and better understanding of the role of the basal ganglia in dystonia. The word "dystonia" describes a phenotype of involuntary movement that may manifest from a variety of conditions. Dystonia may affect only certain regions of the body or may be generalized. It appears to be critical to determine whether the etiology underlying the dystonia is "primary" (ie, occurring from a genetic or idiopathic origin) or "secondary" (ie, occurring as a result of structural, metabolic, or neurodegenerative disorders). Secondary dystonias are far more common than primary dystonias. Primary dystonias respond well to pallidotomy or deep brain stimulation of the internal segment of the globus pallidum, whereas secondary dystonias appear to respond partially at best. Limited historic and current data suggest that the thalamus may be a promising target for the treatment of secondary dystonias, but more careful, prospective, randomized studies are needed. Combinations of bilateral targets are possible with the current technology of DBS, but not widely used due to surgical morbidity and expense. This article reviews the surgical treatment of dystonia from past to present, with a focus on separating the outcomes for primary versus secondary and generalized versus cervical dystonia.

Post-operative progress of dystonia patients following globus pallidus internus deep brain stimulation.

In the current era of functional surgery for movement disorders, deep brain stimulation (DBS) of the globus pallidus internus (GPi) is emerging as the favoured intervention for patients with dystonia. Here we report our results in 20 patients with medically intractable dystonia treated with GPi stimulation. The series comprised 14 patients with generalized dystonia and six with spasmodic torticollis. Although comparisons were limited by differences in their respective neurological rating scales, chronic DBS clearly benefited both patient groups. Data conveying the rate of change in neurological function following intervention are also presented, demonstrating the gradual but progressive and sustained nature of improvement following stimulation of the GPi in dystonic patients.

Chronic stimulation of the globus pallidus internus for treatment of non-dYT1 generalized dystonia and choreoathetosis: 2-year follow up.

OBJECT: The authors studied the long-term efficacy of deep brain stimulation (DBS) of the posteroventral lateral globus pallidus internus up to 2 years postoperatively in patients with primary non-DYT1 generalized dystonia or choreoathetosis. The results are briefly compared with those reported for DBS in DYT1 dystonia (Oppenheim dystonia), which is caused by the DYT1 gene. METHODS: Enrollment in this prospective expanded pilot study was limited to adult patients with severely disabling, medically refractory non-DYT1 generalized dystonia or choreoathetosis. Six consecutive patients underwent follow-up examinations at defined intervals of 3 months, 1 year, and 2 years postsurgery. There were five women and one man, and their mean age at surgery was 45.5 years. Formal assessments included both the Burke-Fahn-Marsden dystonia scale and the recently developed Unified Dystonia Rating Scale. Two patients had primary generalized non-DYT1 dystonia, and four suffered from choreoathetosis secondary to infantile cerebral palsy. Bilateral quadripolar DBS electrodes were implanted in all instances, except in one patient with markedly asymmetrical symptoms. There were no adverse events related to surgery. The Burke-Fahn-Marsden scores in the two patients with generalized dystonia improved by 78 and 71% at 3 months, by 82 and 69% at 1 year, and by 78 and 70% at 2 years postoperatively. This was paralleled by marked amelioration of disability scores. The mean improvement in Burke-Fahn-Marsden scores in patients with choreoathetosis was 12% at 3 months, 29% at 1 year, and 23% at 2 years postoperatively, which was not significant. Two of these patients thought that they had achieved marked improvement at 2 years postoperatively, although results of objective evaluations were less impressive. In these two patients there was a minor but stable improvement in disability scores. All patients had an improvement in pain scores at the 2-year follow-up review. Medication was tapered off in both patients with generalized dystonia and reduced in two of the patients with choreoathetosis. All stimulation-induced side effects were reversible on adjustment of the DBS settings. Energy consumption of the batteries was considerably higher than in patients with Parkinson disease. CONCLUSIONS: Chronic pallidal DBS is a safe and effective procedure in generalized non-DYT1 dystonia, and it may become the procedure of choice in patients with medically refractory dystonia. Postoperative improvement of choreoathetosis is more modest and varied, and subjective ratings of outcome may exceed objective evaluations.

Stereotactic neurosurgery for movement disorders.

Stereotactic neurosurgery for the treatment of movement disorders focuses primarily on the treatment of Parkinson's disease (PD), essential tremor (ET), and dystonia. The surgical targets in use are the subthalamic nucleus (STN) and the globus pallidus internus (GPi) for PD, GPi for dystonia, and ventralis intermedius (Vim) nucleus of the thalamus for ET. Following target selection, procedures include the generation of lesions or the placement of deep brain stimulating electrodes in the selected target. Additionally, transplantation has been used in the treatment of PD. The indications, outcomes, and risks of the various procedures are reviewed.

Results of deep brain stimulation for dystonia: a critical reappraisal.

Deep brain stimulation for severe dystonia is still in the very first stage of development. Only single case reports or small case series have been reported to date. Best results have been obtained with pallidal stimulation in patients with primary generalised dystonia, especially in DYT1 mutation carriers. In secondary dystonia, conflicting results were reported. However, there is today enough promising evidence for a striking efficacy of pallidal stimulation in dystonia, supporting the need for further investigations in the field, with collaborative projects (regarding to the limited number of eligible patients); double-blind studies, including a consensus about surgical method; and a precise anatomic analysis of the position of the electrode. A careful assessment of the efficacy by using improved clinical scale is also warranted.

Methods for programming and patient management with deep brain stimulation of the globus pallidus for the treatment of advanced Parkinson's disease and dystonia.

Globus pallidus (GPi) deep brain stimulation can markedly improve severe medication-refractory Parkinson's disease (PD) and dystonia. Appropriate perioperative patient management can assist with electrode implantation. Optimizing stimulation settings and simultaneously adjusting medications (when appropriate) can substantially improve patient outcomes. Although there are a large number of possible stimulation settings, in clinical practice, a relatively narrow range of settings has been shown to be most efficacious. A systematic approach to determining those settings that maximally improve parkinsonism and suppress drug-induced dyskinesias is outlined following a clear algorithm that uses the observation that stimulation of the dorsal and ventral pallidum has been shown to have opposite motor effects in PD. Based on the available literature, recommendations are also made for the use of GPi deep brain stimulation in dystonia.

Postanoxic generalized dystonia improved by bilateral Voa thalamic deep brain stimulation.

A patient with severe postanoxic dystonia and bilateral necrosis of the basal ganglia, who was confined to a wheelchair, underwent bilateral ventralis oralis anterior deep brain stimulation (Voa-DBS) after 6 weeks of unsuccessful bilateral pallidal DBS (GPi-DBS). After 4 months of high intensity Voa-DBS, cognitively unimpaired, he showed major improvement in dystonia, became ambulant, but committed suicide. Brain examination confirmed the correct location of the electrodes in GPi and Voa on both sides.