Deep Brain Stimulation of the Globus Pallidus Internus and Externus in Multiple System Atrophy

Background

Multiple system atrophy with parkinsonism (MSA-P) is a progressive condition with no effective treatment.

Objective

The aim of this study was to describe the safety and efficacy of deep brain stimulation (DBS) of globus pallidus pars interna and externa in a cohort of patients with MSA-P.

Methods

Six patients were included. Changes in Movement Disorders Society Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS III), Parkinson's Disease Questionnaire (PDQ-39) scores, and levodopa equivalent daily dose were compared before and after DBS. Electrode localization and volume tissue activation were calculated.

Results

DBS surgery did not result in any major adverse events or intraoperative complications. Overall, no differences in MDS-UPDRS III scores were demonstrated (55.2 ± 17.6 preoperatively compared with 67.3 ± 19.2 at 1 year after surgery), although transient improvement in mobility and dyskinesia was reported in some subjects.

Conclusions

Globus pallidus pars interna and externa DBS for patients with MSA-P did not result in major complications, although it did not provide significant clinical benefit as measured by MDS-UPDRS III. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.     

Pallidal Deep Brain Stimulation in Primary Cervical Dystonia with Phasic Type : Clinical Outcome and Postoperative Course

Objective

The purpose of this study was to analyze in detail the relationship between outcome and time course of effect in medically refractory primary cervical dystonia (CD) with phasic type that was treated by bilateral globus pallidus internus (Gpi) deep brain stimulation (DBS).

Methods

Six patients underwent bilateral implantation of DBS into the Gpi under the guide of microelectrode recording and were followed for 18.7 ± 11.1 months. The mean duration of the CD was 5.8 ± 3.4 years. The mean age at time of surgery was 54.2 ± 10.2 years. Patients were evaluated with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and relief scale using patient self-reporting.

Results

The TWSTRS total scores improved by 64.5%, 65.5%, 75.8%, and 76.0% at 3, 6, 12 months, and at the last available follow-up after surgery, respectively. Statistically significant improvements in the TWSTRS scores were observed 3 months after surgery (p = 0.028) with gradual improvement up to 12 months after surgery, thereafter, the improvement was sustained. However, there was no statistically significant difference between the scores at 3 and 12 months. Subjective improvement reported averaged 81.7 ± 6.8% at last follow-up. Mild dysarthria, the most frequent adverse event, occurred in 3 patients.

Conclusions

Our results show that the bilateral Gpi-DBS can offer a significant therapeutic effect from 3 months postoperatively in patients with primary CD with phasic type, without significant side effects.     

Pallidal stimulation in cervical dystonia: clinical implications of acute changes in stimulation parameters

Background and purpose:  Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is successful in dystonia, but the role of each electrical parameters of stimulation is unclear. We studied the clinical effects of acute changes of different parameters of GPi–DBS in cervical dystonia (CD).
Methods:  Eight CD patients with bilateral GPi–DBS at 28.6 ± 19.2 (mean ± SD) months after surgery were recruited. Mean improvement in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) severity score was 54.5% compared to before surgery. Ten settings, including a combination of a wide range of pulse widths (PWs), low and high frequencies and voltage, were administered in a randomized double blinded fashion. Clinical benefit was assessed by two raters using the TWSTRS and by the patients using an analogue rating scale.
Results:  The TWSTRS severity scores were reduced by 56.7% with stimulation at the best settings. Improvement was significantly associated with high frequency (≥60 Hz) and high voltage. Stimulation at 130 Hz showed the best clinical improvement. Increasing PWs (from 60 to 450 μs) did not result in a significant improvement.
Conclusion:  Frequency and amplitude appear to be the most important factors in the acute anti-dystonic effects in GPi–DBS patients with CD.     

Asleep Deep Brain Stimulation in Patients With Isolated Dystonia: Stereotactic Accuracy,Efficacy, and Safety

ObjectivesLead placement for deep brain stimulation (DBS) is routinely performed using neuroimaging or microelectrode recording (MER). Recent studies have demonstrated that DBS under general anesthesia using an imaging-guided target technique (“asleep” DBS) can be performed accurately and effectively with lower surgery complication rates than the MER-guided target method under local anesthesia (“awake” DBS). This suggests that asleep DBS may be a more acceptable method. However, there is limited direct evidence focused on isolated dystonia using this method. Therefore, this study aimed to investigate the clinical outcomes and targeting accuracy in patients with dystonia who underwent asleep DBS.Materials and MethodsWe examined 56 patients (112 leads) with isolated dystonia who underwent asleep DBS targeting in the globus pallidus internus (GPi) and subthalamic nucleus (STN). The Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) scores were assessed preoperatively and at 12-month follow-up (12 m-FU). The lead accuracy was evaluated by comparing the coordinates of the preoperative plan with those of the final electrode implantation location. Other measures analyzed included stimulation parameters and adverse events (AEs).ResultsFor both GPi and STN cohorts, mean BFMDRS motor scores were significantly lower at 12 m-FU (8.9 ± 10.9 and 4.6 ± 5.7 points) than at baseline (22.6 ± 16.4 and 16.1 ± 14.1 points, p < 0.001). The mean difference between the planned target and the distal contact of the leads was 1.33 ± 0.54 mm for the right brain electrodes and 1.50 ± 0.57 mm for the left, determined by Euclidian distance. No perioperative complications or AEs related to the device were observed during the complete follow-up. However, AEs associated with stimulation occurred in 12 and 6 patients in the GPi and STN groups, respectively.ConclusionsAsleep DBS may be an accurate, effective, and safe method for treating patients with isolated dystonia regardless of the stimulation target.     

STN vs. Pallidal Stimulation in Parkinson Disease: Improvement With Experience and Better Patient Selection

Objectives. This is a prospective study to determine the outcomes of subthalamic nucleus (STN) vs. globus pallidus internus (GPi) deep brain stimulation (DBS) at our institution. Materials and Methods. We studied a total of 39 patients — 29 with STN and 10 with GPi DBS over a period of up to 6 years. Mean ages in the two groups were similar (59 and 60 years, respectively) and disease duration prior to implantation was similar (9.6 and 11.7 years, respectively). Unified Parkinson Disease Rating Scale (UPDRS) was recorded preoperatively and at follow‐up (at least at 6‐month intervals). Medications also were recorded, and each patient's levodopa equivalent units (LEU) were calculated. Results were analyzed using a paired Student's t‐test. Results. LEU reduced significantly (p < 0.05) in the STN group (5.7 to 3.7) but not the GPi group. Both targets significantly improved part 3 and part 4 scores of the UPDRS but GPi DBS did not improve part 2 scores (activities of daily living). STN DBS had much better outcome on the motor “off” scores of the UPDRS, whereas GPi only improved tremor. A comparison of the “earliest 10” and “most recent 10” STN patients showed a significant improvement in outcome in the most recent cases. Conclusions. In our group, STN was more effective for alleviating the symptoms of Parkinson disease, even in older patients with significant dyskinesias. Better patient selection and greater experience have led to more improvement in the more recent patients.     

Posttraumatic Hemidystonia Treated with Unilateral Globus Pallidus Interna Stimulation: Long‐Term Follow‐up and Radiologic Features

Objective: Hemidystonia is a unilateral clinical presentation of dystonia, and it is usually refractory to current methods of medical treatment. Recently, deep brain stimulation has given some hope of recovery to dystonic patients. Materials and Methods: A 30‐year‐old right‐handed man with no abnormal perinatal history or family history of movement disorders was admitted to our institution. The patient had suffered right‐sided dystonia for more than three years after severe head trauma sustained four years prior. Results: We performed a stereotactic implantation of an electrode into the left globus pallidus internus (GPi) and he showed excellent response to pallidal stimulation during long‐term follow‐up. Conclusions: We present a unique case of secondary posttraumatic hemidystonia treated with contralateral GPi stimulation with an excellent outcome. Pallidal stimulation can be a good treatment option for posttraumatic hemidystonia in selected cases.     

Pallidal and thalamic deep brain stimulation in myoclonus‐dystonia

Deep brain stimulation (DBS) of the internal globus pallidus (GPi) and ventral intermediate thalamic nucleus (VIM) are established treatment options in primary dystonia and tremor syndromes and have been reported anecdotally to be efficacious in myoclonus‐dystonia (MD). We investigated short‐ and long‐term effects on motor function, cognition, affective state, and quality of life (QoL) of GPi‐ and VIM‐DBS in MD. Ten MD‐patients (nine ε‐sarcoglycan‐mutation‐positive) were evaluated pre‐ and post‐surgically following continuous bilateral GPi‐ and VIM‐DBS at four time points: presurgical, 6, 12, and as a last follow‐up at a mean of 62.3 months postsurgically, and in OFF‐, GPi‐, VIM‐, and GPi‐VIM‐DBS conditions by validated motor [unified myoclonus rating scale (UMRS), TSUI Score, Burke‐Fahn‐Marsden dystonia rating scale (BFMDRS)], cognitive, affective, and QoL‐scores. MD‐symptoms significantly improved at 6 months post‐surgery (UMRS: 61.5%, TSUI Score: 36.5%, BFMDRS: 47.3%). Beneficial effects were sustained at long‐term evaluation post‐surgery (UMRS: 65.5%, TSUI Score: 35.1%, BFMDRS: 48.2%). QoL was significantly ameliorated; affective status and cognition remained unchanged postsurgically irrespective of the stimulation conditions. No serious long‐lasting stimulation‐related adverse events (AEs) were observed. Both GPi‐ and VIM‐DBS offer equally effective and safe treatment options for MD. With respect to fewer adverse, stimulation‐induced events of GPi‐DBS in comparison with VIM‐DBS, GPi‐DBS seems to be preferable. Combined GPi‐VIM‐DBS can be useful in cases of incapaciting myoclonus, refractory to GPi‐DBS alone. © 2010 Movement Disorder Society     

Globus pallidus internus versus subthalamic nucleus deep brain stimulation for isolated dystonia: A 3-year follow-up

Background and purpose

Bilateral deep brain stimulation (DBS) surgery targeting the globus pallidus internus (GPi) or the subthalamic nucleus (STN) is widely used in medication-refractory dystonia. However, evidence regarding target selection considering various symptoms remains limited. This study aimed to compare the effectiveness of these two targets in patients with isolated dystonia.

Methods

This retrospective study evaluated 71 consecutive patients (GPi-DBS group, n = 32; STN-DBS group, n = 39) with isolated dystonia. Burke–Fahn–Marsden Dystonia Rating Scale scores and quality of life were evaluated preoperatively and at 1, 6, 12, and 36 months postoperatively. Cognition and mental status were assessed preoperatively and at 36 months postoperatively.

Results

Targeting the STN (STN-DBS) yielded effects within 1 month (65% vs. 44%; p = 0.0076) and was superior at 1 year (70% vs. 51%; p = 0.0112) and 3 years (74% vs. 59%; p = 0.0138). For individual symptoms, STN-DBS was preferable for eye involvement (81% vs. 56%; p = 0.0255), whereas targeting the GPi (GPi-DBS) was better for axis symptoms, especially for the trunk (82% vs. 94%; p = 0.015). STN-DBS was also favorable for generalized dystonia at 36-month follow-up (p = 0.04) and required less electrical energy (p < 0.0001). Disability, quality of life, and depression and anxiety measures were also improved. Neither target influenced cognition.

Conclusions

We demonstrated that the GPi and STN are safe and effective targets for isolated dystonia. The STN has the benefits of fast action and low battery consumption, and is superior for ocular dystonia and generalized dystonia, while the GPi is better for trunk involvement. These findings may offer guidance for future DBS target selection for different types of dystonia.     

Pallidal deep brain stimulation improves quality of life in segmental and generalized dystonia: Results from a prospective,randomized sham‐controlled trial

As part of the first randomized, sham‐timulation controlled trial on deep brain stimulation (DBS) in primary segmental or generalized dystonia, health‐related quality of life (HRQoL) was assessed by SF‐36. After the 3‐month sham‐controlled phase, significant HRQoL improvement occurred only in the active‐stimulation group. The open‐label extension phase resulted in a significant improvement in all SF‐36 domains following 6 months of neurostimulation. These results demonstrate a favorable impact of DBS on HRQoL in primary dystonia. © 2007 Movement Disorder Society