Bilateral subthalamic nucleus deep brain stimulation for refractory isolated cervical dystonia.

Subthalamic nucleus (STN) deep brain stimulation (DBS) has been proven to be an alternative target choice for refractory isolated cervical dystonia (CD). However, assessments of its short and long-term safety, efficacy, and sustained effectiveness have been limited to few reports. Here, we evaluated nine consecutive refractory isolated CD patients who underwent bilateral STN DBS and accepted to short and long-term follow-up in this retrospective study. Seven time points were used to see the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores (pre-operation [baseline], 1, 3, 6, 12, 24 months post-operation and last follow-up) to assess improvement of dystonic symptoms. The 36-item Short-Form General Health Survey (SF-36) scores obtained at pre-operation and last follow-up to assess the changes in quality of life. All patients tolerated surgery well and acquired observable clinical benefits from STN DBS therapy. All patients achieved a considerable improvement in quality of life at the last follow-up. The hardware-related adverse events can be tolerated and the stimulation-related adverse events can be ameliorated by programming. Our data support the idea that bilateral STN DBS is a safety and effective method for the treatment of refractory isolated CD, with persistent and remarkable improvement in both movement and quality of life.

Neurophysiological responses of globus pallidus internus during the auditory oddball task in Parkinson's disease.

Parkinson's disease can be associated with significant cognitive impairment that may lead to dementia. Deep brain stimulation (DBS) of the subthalamic nucleus is an effective therapy for motor symptoms but is associated with cognitive decline. DBS of globus pallidus internus (GPi) poses less risk of cognitive decline so may be the preferred target. A research priority is to identify biomarkers of cognitive decline in this population, but efforts are hampered by a lack of understanding of the role of the different basal ganglia nuclei, such as the globus pallidus, in cognitive processing. During deep brain stimulation (DBS) surgery, we monitored single units, beta oscillatory LFP activity as well as event related potentials (ERPs) from the globus pallidus internus (GPi) of 16 Parkinson's disease patients, while they performed an auditory attention task. We used an auditory oddball task, during which one standard tone is presented at regular intervals and a second deviant tone is presented with a low probability that the subject is requested to count and report at the end of the task. All forms of neuronal activity studied were selective modulated by the attended tones. Of 62 neurons studied, the majority (51 or 82%) responded selectively to the deviant tone. Beta oscillatory activity showed an overall desynchronization during both types of attended tones interspersed by bursts of beta activity giving rise to peaks at a latency of around 200 ms after tone onset. cognitive ERPs recorded in GPi were selective to the attended tone and the right-side cERP was larger than the left side. The averages of trials showing a difference in beta oscillatory activity between deviant and standard also had a significant difference in cERP amplitude. In one block of trials, the random occurrence of 3 deviant tones in short succession silenced the activity of the GPi neuron being recorded. Trial blocks where a clear difference in LFP beta was seen were twice as likely to yield a correct tone count (25 vs 11). The data demonstrate strong modulation of GPi neuronal activity during the auditory oddball task. Overall, this study demonstrates an involvement of GPi in processing of non-motor cognitive tasks such as working memory and attention, and suggests that direct effects of DBS in non-motor GPi may contribute to cognitive changes observed post-operatively.

Subthalamic and Pallidal Stimulations in Patients with Parkinson's Disease: Common and Dissociable Connections.

OBJECTIVE: The subthalamic nucleus (STN) and internal globus pallidus (GPi) are the most effective targets in deep brain stimulation (DBS) for Parkinson's disease (PD). However, the common and specific effects on brain connectivity of stimulating the 2 nuclei remain unclear. METHODS: Patients with PD receiving STN-DBS (n = 27, 6 women, mean age 64.8 years) or GPi-DBS (n = 28, 13 women, mean age 64.6 years) were recruited for resting-state functional magnetic resonance imaging to assess the effects of STN-DBS and GPi-DBS on brain functional dynamics. RESULTS: The functional connectivity both between the somatosensory-motor cortices and thalamus, and between the somatosensory-motor cortices and cerebellum decreased in the DBS-on state compared with the off state (p < 0.05). The changes in thalamocortical connectivity correlated with DBS-induced motor improvement (p < 0.05) and were negatively correlated with the normalized intersection volume of tissues activated at both DBS targets (p < 0.05). STN-DBS modulated functional connectivity among a wider range of brain areas than GPi-DBS (p = 0.009). Notably, only STN-DBS affected connectivity between the postcentral gyrus and cerebellar vermis (p < 0.001) and between the somatomotor and visual networks (p < 0.001). INTERPRETATION: Our findings highlight common alterations in the motor pathway and its relationship with the motor improvement induced by both STN- and GPi-DBS. The effects on cortico-cerebellar and somatomotor-visual functional connectivity differed between groups, suggesting differentiated neural modulation of the 2 target sites. Our results provide mechanistic insight and yield the potential to refine target selection strategies for focal brain stimulation in PD. ANN NEUROL 2021;90:670-682.

Successful Unilateral Surgical Approach to Internal Globus Pallidus and Ventral Intermediate Nucleus of the Thalamus in 3 Cases of Myoclonus-Dystonia Syndrome.

Surgical approaches of internal globus pallidus (GPi) and ventral intermediate thalamic nucleus (Vim) have been used to treat different movement disorders. Three subjects with myoclonus-dystonia syndrome were surgically treated, one of them with GPi and Vim stimulation, while radiofrequency ablation of these structures was performed in the other 2 subjects. Surgical approach of both targets was performed simultaneously on each subject. Mean follow-up was of 33.3 months (22-48 months), the Unified Myoclonus Rating Scale action myoclonus (AM), functional tests (FT), patient questionnaire (PQ) sub-scores, and the Unified Dystonia Rating Scale (UDRS) were used during assessments. Improvement in all scales were seen 6 months after surgery (AM: 74%, FT: 60%, PQ: 63%, UDRS: 65%), and this benefit persisted throughout follow-up (AM: 61%, FT:62%, PQ: 65%, UDRS: 86%). No adverse events were noticed. Simultaneous unilateral procedures of GPi and Vim by either stimulation or ablation techniques improve both motor and functional scores in myoclonus-dystonia syndrome.

Predicting final lesion characteristics during MR-guided focused ultrasound pallidotomy for treatment of Parkinson's disease.

OBJECTIVE: Magnetic resonance-guided focused ultrasound (MRgFUS) ablation of the globus pallidus interna (GPi) is being investigated for the treatment of advanced Parkinson's disease symptoms. However, GPi lesioning presents unique challenges due to the off-midline location of the target. Furthermore, it remains uncertain whether intraprocedural MR thermometry data can predict final lesion characteristics. METHODS: The authors first performed temperature simulations of GPi pallidotomy and compared the results with those of actual cases and the results of ventral intermediate nucleus (VIM) thalamotomy performed for essential tremor treatment. Next, thermometry data from 13 MRgFUS pallidotomy procedures performed at their institution were analyzed using 46°C, 48°C, 50°C, and 52°C temperature thresholds. The resulting thermal models were compared with resulting GPi lesions noted on postprocedure days 1 and 30. Finally, the treatment efficiency (energy per temperature rise) of pallidotomy was evaluated. RESULTS: The authors' modeled acoustic intensity maps correctly demonstrate the elongated, ellipsoid lesions noted during GPi pallidotomy. In treated patients, the 48°C temperature threshold maps most accurately predicted postprocedure day 1 lesion size, while no correlation was found for day 30 lesions. The average energy/temperature rise of pallidotomy was higher (612 J/°C) than what had been noted for VIM thalamotomy and varied with the patients' skull density ratios (SDRs). CONCLUSIONS: The authors' acoustic simulations accurately depicted the characteristics of thermal lesions encountered following MRgFUS pallidotomy. MR thermometry data can predict postprocedure day 1 GPi lesion characteristics using a 48°C threshold model. Finally, the lower treatment efficiency of pallidotomy may make GPi lesioning challenging in patients with a low SDR.

Postmortem Dissections of Common Targets for Lesion and Deep Brain Stimulation Surgeries.

BACKGROUND: The subthalamic nucleus (STN), globus pallidus internus (GPi), and pedunculopontine nucleus (PPN) are effective targets for deep brain stimulation (DBS) in many pathological conditions. Previous literature has focused on appropriate stimulation targets and their relationships with functional neuroanatomic pathways; however, comprehensive anatomic dissections illustrating these nuclei and their connections are lacking. This information will provide insight into the anatomic basis of stimulation-induced DBS benefits and side effects. OBJECTIVE: To combine advanced cadaveric dissection techniques and ultrahigh field magnetic resonance imaging (MRI) to explore the anatomy of the STN, GPi, and PPN with their associated fiber pathways. METHODS: A total of 10 cadaveric human brains and 2 hemispheres of a cadaveric head were examined using fiber dissection techniques. The anatomic dissections were compared with 11.1 Tesla (T) structural MRI and 4.7 T MRI fiber tractography. RESULTS: The extensive connections of the STN (caudate nucleus, putamen, medial frontal cortex, substantia innominata, substantia nigra, PPN, globus pallidus externus (GPe), GPi, olfactory tubercle, hypothalamus, and mammillary body) were demonstrated. The connections of GPi to the thalamus, substantia nigra, STN, amygdala, putamen, PPN, and GPe were also illustrated. The PPN was shown to connect to the STN and GPi anteriorly, to the cerebellum inferiorly, and to the substantia nigra anteriorly and superiorly. CONCLUSION: This study demonstrates connections using combined anatomic microdissections, ultrahigh field MRI, and MRI tractography. The anatomic findings are analyzed in relation to various stimulation-induced clinical effects. Precise knowledge of neuroanatomy, anatomic relationships, and fiber connections of the STN, GPi, PPN will likely enable more effective targeting and improved DBS outcomes.

Pallidothalamic Tractotomy for Parkinson Disease with 1-Year Follow-Up: A Case Report.

BACKGROUND: The pallidothalamic tract connects the globus pallidus internus and the ventrolateral portion of the thalamus, and ablation of the pallidothalamic tract (pallidothalamic tractotomy [PTT]) reportedly exerts antiparkinsonian effects. However, the detailed clinical course has not yet been elucidated. Here, we present the first single case report of PTT performed in a patient with Parkinson disease, with 1-year follow-up. CASE DESCRIPTION: The patient was a 68-year-old woman with Parkinson disease. After 14 years of receiving oral medication, she experienced the "wearing-off" phenomenon. Levodopa (300 mg/day) was required to maintain daily activities. Rigidity and peak-dose dyskinesia were predominantly observed in the right side of her body. In addition, she demonstrated right foot dystonia with pain. The preoperative Unified Parkinson Disease Rating Scale part 1, 2 (off medication/on medication), 3 (off medication/on medication), and 4 scores were 7, 26/4, 41/23, and 13, respectively. Further, the preoperative Unified Dyskinesia Rating Scale and Parkinson Disease Questionnaire-39 scores were 102 and 46, respectively. She underwent left-sided PTT, and no perioperative complications were observed. At 1 year postoperatively, daily administration of levodopa (200 mg) was maintained without an "off" condition all day. The 1-year Unified Parkinson Disease Rating Scale part 1, 2, 3, and 4 scores were 5, 9/1, 20/12, and 5, respectively. In addition, the 1-year Unified Dyskinesia Rating Scale and Parkinson Disease Questionnaire-39 scores were 20 and 20, respectively. CONCLUSIONS: We present a rare case of PTT performed in a patient with Parkinson disease. PTT might be useful in patients who do not desire device implantation.

Combined Unilateral Posteroventral Pallidotomy and Ventral Intermediate Nucleus Thalamotomy in Tremor-Dominant Parkinson's Disease versus Posteroventral Pallidotomy Alone: A Prospective Comparative Study.

BACKGROUND: The optimum target in surgery for Parkinson's disease (PD) is still controversial, especially in patients with tremor-dominant PD. We aim to compare results in tremor-dominant patients undergoing pallidotomy vs. those undergoing simultaneous posteroventral pallidotomy (PVP) and ventral intermediate nucleus (VIM) thalamotomy. METHODS: Twenty-four patients with tremor-dominant PD were included in this study. Twelve patients received unilateral PVP contralateral to the most affected side. The other 12 patients received simultaneous unilateral PVP and VIM thalamotomy contralateral to the most affected side. Assessment of results in both groups was achieved using both UPDRS "off" motor scores and UPDRS rest tremor subscores. RESULTS: The mean UPDRS off motor score improved in the pallidotomy group from 61.3 preoperatively to 36.8 at 12 months. In the combined group, it improved from 59.6 to 35.2 at 12 months, with no statistically significant difference between both groups. On the other hand, while the mean tremor subscore in the pallidotomy group improved from a mean of 2.3-0.8, the tremors were abolished in all of the patients in the combined group except for 1 patient who showed slight infrequent tremors at 12 months. CONCLUSION: Patients with tremor-dominant PD achieve more improvement in tremor control after combined PVP and VIM thalamotomy.

The Pioneering and Unknown Stereotactic Approach of Roeder and Orthner from Göttingen. Part II: Long-Term Outcome and Postmortem Analysis of Bilateral Pallidotomy in the Pre-Levodopa Era.

Before the advent of levodopa, pallidotomy was initially the most effective treatment for Parkinson disease, but it was soon superseded by thalamotomy. It is widely unknown that, similar to Leksell, 2 neurologists from Göttingen, Orthner and Roeder, perpetuated pallidotomy against the mainstream of their time. Postmortem studies demonstrated that true posterior and ventral pallidoansotomy sparing the overwhelming mass of the pallidum was accomplished. This was due to a unique and individually tailored stereotactic technique even allowing bilateral staged pallidotomies. In 1962, the long-term effects (3-year follow-up on average) of the first 18 out of 36 patients with staged bilateral pallidotomies were reported in great detail. Meticulous descriptions of each case indicate long-term improvements in parkinsonian rigidity and associated pain, as well as posture, gait, and akinesia (e.g., improved repetitive movements and arm swinging). Alleviation of tremor was found to require larger lesions than needed for suppression of rigidity. No improvement in speech, drooling, or seborrhea was observed. By 1962, the team had operated 13 patients with postencephalitic oculogyric crises with remarkable results (mean follow-up: 5 years). They also described alleviation of nonparkinsonian hyperkinetic disorders (e.g., hemiballism and chorea) with pallidotomy. The reported rates for surgical mortality and other complications had been remarkably low, even if compared to those reported after the revival of pallidotomy by Laitinen in the post-levodopa era. This applies also to bilateral pallidotomy performed with a positive risk-benefit ratio that has remained unparalleled to date. The intricate history of pallidotomy for movement disorders is incomplete without an appreciation of the achievements of the Göttingen group.

Unilateral thalamic and pallidal deep brain stimulation for idiopathic hemidystonia: results of individual and combined stimulations. Case report.

Pallidal stimulation has been the usual surgical treatment for dystonia in the last decades. The continuous investigation of the physiopathology and the motor pathways involved leads to the search for complementary targets to improve results. The authors present the case of a 37-year-old woman who had suffered from idiopathic hemidystonia with hyperkinetic and hypokinetic movements for 11 years, and who was treated with deep brain stimulation. A brief literature review is also provided. The globus pallidus internus and the ventral intermediate/ventral oral posterior complex of the thalamus were stimulated separately and simultaneously for 3 months and compared using the Burke-Fahn-Marsden Dystonia Rating Scale and the Global Dystonia Severity Rating Scale, with a 3.5-year follow-up. The synergism of multiple-target stimulation resulted in a complete improvement of the mixed dystonic symptoms.

Effects of neurostimulation for advanced Parkinson's disease patients on motor symptoms: A multiple-treatments meta-analysas of randomized controlled trials.

Deep brain stimulation (DBS) is the surgical procedure of choice for patients with advanced Parkinson disease (PD). We aim to evaluate the efficacy of GPi (globus pallidus internus), STN (subthalamic nucleus)-DBS and medical therapy for PD. We conducted a systematic review and multiple-treatments meta-analysis to investigate the efficacy of neurostimulation and medical therapy for PD patients. Sixteen eligible studies were included in this analysis. We pooled the whole data and found obvious difference between GPi-DBS versus medical therapy and STN-DBS versus medical therapy in terms of UPDRS scores (Unified Parkinson's Disease Rating Scale). Meanwhile, we found GPi-DBS had the similar efficacy on the UPDRS scores when compared with STN-DBS. What is more, quality of life, measured by PDQ-39 (Parkinson's disease Questionnaire) showed greater improvement after GPi-DBS than STN-DBS. Five studies showed STN-DBS was more effective for reduction in medication than GPi-DBS. Overall, either GPi-DBS or STN-DBS was an effective technique to control PD patients' symptoms and improved their functionality and quality of life. Meanwhile, the UPDRS scores measuring parkinsonian symptoms revealed no significant difference between GPi-DBS and STN-DBS. STN-DBS was more effective for reduction in medication than GPi-DBS. Alternatively, GPi-DBS was more effective for improving the PDQ-39 score than STN-DBS.

Sixteen years of deep brain stimulation in Tourette's Syndrome: a critical review.

INTRODUCTION: The aim of this paper was to perform a critical and systematic review of the published papers on deep brain stimulation (DBS) for Tourette's Syndrome (TS). EVIDENCE ACQUISITION: A PubMed search on DBS in TS was conducted selecting papers that reported on the clinical outcome of DBS. EVIDENCE SYNTHESIS: The majority of papers were case reports or small series. The thalamus and the globus pallidus internus appear to be the most promising targets. However, in light of the great methodological diversity a balanced comparison of clinical outcome and understanding of the role of DBS in TS remains difficult. CONCLUSIONS: Despite 16 years of experience with DBS in TS a consensus on many issues, foremost on target selection and the age of inclusion continue to be missing. Class I evidence and international collaborations, to increase the number of included patients, are urgently needed, in order to evaluate further the role of DBS in TS.

Successful Combination of Pallidal and Thalamic Stimulation for Intractable Involuntary Movements in Patients with Neuroacanthocytosis.

OBJECTIVE: Neuroacanthocytosis (NA) is a rare neurodegenerative disease that involves severe involuntary movements including chorea, dystonia, and trunk spasms. Current treatments are not effective for these involuntary movements. Although there are a few reports on the use of deep brain stimulation to treat patients with NA, the optimal stimulation target is not yet definitive. Some authors have reported successful improvement of NA symptoms with stimulation of the globus pallidum interna, and others have reported a reduction in trunk spasm with stimulation of the ventralis oralis complex of the thalamus. We investigated whether the optimal target is well defined for NA. METHODS: We describe the effect of combination stimulation of the globus pallidum interna and the ventralis oralis complex of the thalamus in 2 patients with NA who presented with severe intractable involuntary movements. RESULTS: Gpi stimulation alone was an insufficient effect for trunk spasm and/or chorea. Vo complex stimulation given without Gpi stimulation resulted in improvement of trunk spasm after 2 weeks and might also have had an incomplete effect on involuntary movement including a chorea. The combination of Gpi and Vo complex stimulation reduced the trunk spasms and chorea. This improvement was maintained at 3 months after surgery. The Unified Huntington's Disease Rating Scale score at 1 year after surgery was lower than that before surgery. CONCLUSIONS: Gpi stimulation appears to be insufficient to control violent involuntary movements; therefore, combined GPi and Vo complex stimulation provided some moderate advantage over Gpi stimulation alone.

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.

Acute complications of movement disorders surgery: effects of age and comorbidities.

The most common indication for movement disorder surgery is Parkinson's disease (PD), and the incidence of PD increases with age. The analysis reported here was undertaken with the primary goal of examining whether there is a relationship between peri-operative complications and age. The Nationwide Inpatient Sample (Agency for Healthcare Research and Quality, Rockville, MD, USA) was queried for 10 years beginning in 1999 for patients undergoing deep brain stimulator insertion, pallidotomy, and thalamotomy for treatment of PD, essential tremor, and dystonia. Inpatient complications, including death, stroke (both ischemic and hemorrhagic), and other overall complications were examined. The relative risks associated with advanced age; primary diagnosis; treatment modality; the diagnoses of hypertension, diabetes, and nicotinism; and the cumulative number of comorbidities were examined. There were 5464 patients who met inclusion criteria, including 4145 patients treated for PD and 4961 patients treated with deep brain stimulation (DBS). Overall in-hospital mortality was 0.26%, with 0.15% related to surgical factors. There was a correlation between in-hospital mortality, increasing age, and number of medical comorbidities. After multivariate regression no factor remained predictive of mortality. Having more than 1 medical comorbidity or PD increased the risk of in-hospital complications. Patients with PD were more likely to suffer hemorrhage or stroke. Hypertension, diabetes, nicotinism, and modality of treatment were not associated with increased mortality, hemorrhage or stroke risk, or in-hospital mortality in univariate or multivariate analysis. Both age and medical comorbidity are correlated with in-hospital complications, but age appears to serve as a surrogate for comorbidity. Surgery for PD appears to carry an increased risk of hemorrhage or stroke and in-hospital complications.

The subthalamic microlesion story in Parkinson's disease: electrode insertion-related motor improvement with relative cortico-subcortical hypoactivation in fMRI.

Electrode implantation into the subthalamic nucleus for deep brain stimulation in Parkinson's disease (PD) is associated with a temporary motor improvement occurring prior to neurostimulation. We studied this phenomenon by functional magnetic resonance imaging (fMRI) when considering the Unified Parkinson's Disease Rating Scale (UPDRS-III) and collateral oedema. Twelve patients with PD (age 55.9± (SD)6.8 years, PD duration 9-15 years) underwent bilateral electrode implantation into the subthalamic nucleus. The fMRI was carried out after an overnight withdrawal of levodopa (OFF condition): (i) before and (ii) within three days after surgery in absence of neurostimulation. The motor task involved visually triggered finger tapping. The OFF/UPDRS-III score dropped from 33.8±8.7 before to 23.3±4.8 after the surgery (p<0.001), correlating with the postoperative oedema score (p<0.05). During the motor task, bilateral activation of the thalamus and basal ganglia, motor cortex and insula were preoperatively higher than after surgery (p<0.001). The results became more enhanced after compensation for the oedema and UPDRS-III scores. In addition, the rigidity and axial symptoms score correlated inversely with activation of the putamen and globus pallidus (p<0.0001). One month later, the OFF/UPDRS-III score had returned to the preoperative level (35.8±7.0, p = 0.4).In conclusion, motor improvement induced by insertion of an inactive electrode into the subthalamic nucleus caused an acute microlesion which was at least partially related to the collateral oedema and associated with extensive impact on the motor network. This was postoperatively manifested as lowered movement-related activation at the cortical and subcortical levels and differed from the known effects of neurostimulation or levodopa. The motor system finally adapted to the microlesion within one month as suggested by loss of motor improvement and good efficacy of deep brain stimulation.

[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.

Deep brain stimulation for treatment of hemichorea-hemiballism after craniopharyngioma resection: long-term follow-up.

Hemichorea-hemiballism is a rare movement disorder that has various causes. In treatment-resistant cases, both thalamic and pallidal functional procedures have been shown to yield beneficial results. Until now it has not been clarified whether the thalamus or the pallidum would yield a superior outcome. After resection of a craniopharyngioma in this patient at the age of 49 years, hemichorea-hemiballism developed, with a latency of several weeks. Because the patient was greatly impaired by the movement disorder, she underwent implantation of deep brain stimulation (DBS) electrodes in the thalamic ventralis intermedius nucleus and the posteroventral lateral globus pallidus internus. Although both pallidal and thalamic stimulation could suppress the movement disorder, the voltage needed was clearly less with thalamic than with pallidal stimulation. At the last available follow-up 25 months postoperatively, complete subsidence of hemichorea-hemiballism was achieved with long-term thalamic stimulation. Long-term DBS therapy is an efficient treatment modality for refractory hemichorea-hemiballism in the long run (> 2 years). A bifocal (thalamic and pallidal) target paradigm allowed selection of the optimal stimulation site. Thalamic DBS was more favorable with regard to energy consumption.

Bilateral globus pallidus internus deep brain stimulation for DYT1+ generalized dystonia with previously received bilateral thalamotomy and unilateral pallidotomy.

Ablation of the globus pallidus internus (GPi) and thalamotomy have been extensively used in the past. Posteroventral GPi deep brain stimulation has been considered as a treatment for dystonia. However, to date, there is no report in the literature of any dystonia patient who underwent GPi deep brain stimulation who had previously undergone staged bilateral thalamotomy and unilateral pallidotomy. The authors of the present study have acquired relatively good clinical results, even in patients who previously received bilateral thalamotomy and unilateral pallidotomy for DYT1+ primary generalized dystonia.