Minimal Clinically Important Differences for Burke-Fahn-Marsden Dystonia Rating Scale and 36-Item Short-Form Health Survey.

BACKGROUND: Although an increasing number of trials are reported on the treatment of generalized or segmental isolated dystonia, the minimal clinically important difference thresholds for the most frequently reported outcome measures are still undetermined. OBJECTIVES: To estimate the minimal clinically important difference for the Burke-Fahn-Marsden Dystonia Rating Scale and the 36-Item Short-Form Health Survey in generalized or segmental dystonia. METHODS: A total of 898 paired examinations of 198 consecutive patients, aged >18 years, with idiopathic and inherited (torsin family 1 member A positive) segmental and generalized isolated dystonia were analyzed. To calculate the minimal clinically important difference thresholds, both anchor- and distribution-based methods were used simultaneously. RESULTS: Any improvement >16.6% or worsening larger than 21.5% on the Burke-Fahn-Marsden Dystonia Rating Scale indicates a minimal, yet clinically relevant, change. Threshold values for the Burke-Fahn-Marsden Dystonia Disability Scale were 0.5 points for both decline and improvement. Cut-off scores for the Physical Component Summary, the Mental Component Summary, and the Global (Total or Overall) Score of the 36-Item Short-Form Health Survey were 5.5 and 5.5, 6.5 and 7.5, and 7.5 and 8.5 points for clinically meaningful improvement and deterioration, respectively. CONCLUSIONS: The minimal clinically important difference represents the smallest change in an outcome measure that is meaningful to patients. Our estimates for the Burke-Fahn-Marsden Dystonia Rating Scale and the 36-Item Short-Form Health Survey may allow more reliable judgment of the clinical relevance of different treatments for segmental and generalized isolated dystonia. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

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.

Pallidal versus subthalamic deep brain stimulation for Meige syndrome: A systematic review and meta-analysis.

Background: Globus pallidus internus (GPi) and subthalamic nucleus (STN) are two common deep brain stimulation (DBS) targets. This meta-analysis was to compared the efficacy and safety of these two DBS targets for the treatment of Meige syndrome (MS). Methods: A systematic search was performed using EMBASE, MEDLINE, the Cochrane Library, and ClinicalTrials.gov to identify DBS trials for MS. Review Manager 5.3 was used to perform meta-analysis and the mean difference (MD) was analyzed and calculated with a random effect model. Pearson's correlation coefficients and meta-regression analyses were utilized to identify relevant predictive markers. Results: Twenty trials involving 188 participants with GPi-DBS and 110 individuals with STN-DBS were eligible. Both groups showed improvement of the Burke-Fahn-Marsden Dystonia Rating Scale-Movement (BFMDRS-M) and Disability (BFMDRS-D) scores (BFMDRS-M: MD = 10.57 [7.74-13.41] for GPi-DBS, and MD = 8.59 [4.08-13.11] for STN-DBS; BFMDRS-D: MD = 5.96 [3.15-8.77] for GPi-DBS, and MD = 4.71 [1.38-8.04] for STN-DBS; all P < 0.001) from baseline to the final follow-up, while no notable disparity in improvement rates was observed between them. Stimulation-related complications occurrence was also similar between two groups (38.54 ± 24.07% vs. 43.17 ± 29.12%, P = 0.7594). Simultaneously, preoperative BFMDRS-M score and disease duration were positively connected with the relative changes in BFMDRS-M score at the final visit. Conclusion: Both GPi-DBS and STN-DBS are effective MS therapies, with no differences in efficacy or the frequency of stimulation-related problems. Higher preoperative scores and longer disease duration probably predict greater improvement.

Subthalamus deep brain stimulation for primary dystonia patients: a long-term follow-up study.

BACKGROUND: Deep brain stimulation has generated sustained improvement in motor function for patients with dystonia, but the long-term impact of subthalamic nucleus stimulation on dystonia has not been elucidated. METHODS: Patients with primary dystonia underwent bilateral subthalamic nucleus stimulation and were evaluated with the Burke-Fahn-Marsden dystonia rating scale and the Medical Outcomes Study 36-item Short-Form General Health Survey at baseline and 1 month, 1 year, and 3 to 10 years postoperatively. RESULTS: Improvements in motor function according to the Burke-Fahn-Marsden dystonia rating scale at 1 month, 1 year, and 3 to 10 years of stimulation were 55%, 77%, and 79%, respectively. The quality of life improved after 1 month of stimulation (P < 0.001), progressed within 1 year (P < 0.001), and then remained stable. Disease duration was negatively correlated with an improvement in motor function. CONCLUSIONS: Our results demonstrate that the subthalamus is an alternative to the globus pallidus internus as a target for deep brain stimulation to treat primary dystonia.

An Empirical Comparison of Commonly Used Universal Rating Scales for Dystonia.

Background: There are several widely used clinical rating scales for documenting the severity and distribution of various types of dystonia. Objectives: The goal of this study was to evaluate the performance of the most commonly used scales in a large group of adults with the most common types of isolated dystonia. Methods: Global Dystonia Rating Scale (GDRS) and the Burke-Fahn-Marsden Dystonia Rating Scale (BFM) scores were obtained for 3067 participants. Most had focal or segmental dystonia, with smaller numbers of multifocal or generalized dystonia. These scales were also compared for 209 adults with cervical dystonia that had Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores and 210 adults with blepharospasm that had Blepharospasm Severity Scale (BSRS) scores. Results: There were strong correlations between the GDRS and BFM total scores (r = 0.79) and moderate correlations for their sub scores (r > 0.5). Scores for both scales showed positive skew, with an overabundance of low scores. BFM sub-scores were not normally distributed, due to artifacts caused by the provoking factor. Relevant sub-scores of the GDRS and BFM also showed moderate correlations with the TWSTRS (r > 0.5) for cervical dystonia and the BSRS (r > 0.5) for blepharospasm. Conclusions: The BFM is more widely used than the GDRS, but these results suggest the GDRS may be preferable for focal and segmental dystonias. The overabundance of very low scores for both scales highlights challenges associated with discriminating very mild dystonia from other abnormal movements or variants of normal behavior.

Dystonia in Angelman syndrome: a common, unrecognized clinical finding.

INTRODUCTION: Angelman syndrome (AS) is a neurodevelopmental disorder characterized by cognitive disability, speech impairment, hyperactivity and seizures. Movement disorders have been reported in almost all AS subjects and they are described as "tremulous movements of limbs, unsteadiness, clumsiness or quick, jerky motions". The presence of dystonia has barely been mentioned in subjects with AS and has never been studied in detail. The purpose of this study is to evaluate the prevalence, clinical features and severity of dystonia in a series of adolescents and adults with AS. METHODS: Whole body video recordings of patients with genetically confirmed AS were evaluated. Dystonia was evaluated by mean of the movement subscale of Burke-Fahn-Marsden Dystonia Rating Scale (BFM). RESULTS: Forty-four subjects with AS were evaluated. Fourteen recordings were excluded due to poor cooperation. We finally analyzed data of 30 subjects (15 F) with a median age of 28 years (range 15-51). Dystonia was present in 28/30 (93.3%) subjects. Among these, dystonia involved the upper limbs in 28/28 (100%), lower limbs in 8/28 (28.5%), mouth in 7/28 (25%), neck in 3/28 (10.7%), trunk in 1/28 (3.6%). Severity of dystonia ranged from slight to moderate. There was a linear correlation between severity of dystonia and increasing age. There was no difference in terms of severity of dystonia among genetic subgroups. CONCLUSIONS: Dystonia is a common and previously underrecognized clinical feature of adults and adolescents with AS.

Association of Serum Uric Acid Levels in Meige's Syndrome.

Uric acid (URIC) is a natural antioxidant, and it has been shown that low levels of URIC could be a risk factor for the development of Parkinson's disease. Our aim was to investigate whether URIC also plays a role in Meige's syndrome (MS). We conducted a cohort study to compare serum URIC levels between patients with MS and healthy controls. In addition, we analyzed the impact of URIC on the risk of MS and symptom severity. Compared with normal subjects, URIC content was remarkably decreased in MS patients. In addition, URIC was regarded as a protective factor for MS, as verified by multivariate logistic regression models. We also found non-linear relationships between the levels of serum URIC and the incidence rate of MS and the Burke-Fahn-Marsden dystonia rating scale score. Our study is the first to show a connection between serum URIC levels and MS. Low serum URIC levels indicate an increased risk of MS incidence and more severe clinical symptoms. Our findings provide new insights into the prevention and treatment of MS.

Weight Change After Subthalamic Nucleus Deep Brain Stimulation in Patients With Isolated Dystonia.

Purpose: Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an effective treatment method for advanced Parkinson's disease (PD) and isolated dystonia and provides marked improvement of major motor symptoms. In addition, non-motor effects have been reported including weight gain (WG) in patients with PD after STN-DBS. However, it is still unclear whether patients with isolated dystonia also experience WG. Methods: Data from 47 patients with isolated dystonia who underwent bilateral STN-DBS surgery between October 2012 and June 2019 were retrospectively collected. The severity of dystonia was assessed via the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). Changes in the body mass index (BMI) and BFMDRS score were analyzed using paired Student's t-tests. Regression analysis was performed to identify factors that affected the BMI after surgery. Results: Postoperative WG was observed in 78.7% of patients. The percentage of overweight and obese patients increased from 25.5% (before STN-DBS) to 48.9% (at the last follow-up). The mean BMI and mean percentage change in BMI increased by 1.32 ± 1.83 kg/m2 (P < 0.001) and 6.28 ± 8.34%, respectively. BMI increased more in female than in male patients. At the last follow-up, BFMDRS movement and disability scores improved by 69.76 ± 33.23% and 65.66 ± 31.41%, respectively (both P < 0.001). The final regression model analysis revealed that sex and preoperative BMI alone were independently associated with BMI change (P < 0.05). Conclusions: STN-DBS is associated with postoperative WG with patients with isolated dystonia. WG is more prominent in female patients and is associated with preoperative weight but not with the efficacy of STN-DBS on motor symptoms.

The minimal clinically important change in the motor section of the Burke-Fahn-Marsden Dystonia Rating Scale for generalized dystonia: Results from deep brain stimulation.

BACKGROUND: The minimal clinically important difference (MCID) describes the smallest change in an outcome that is considered clinically meaningful. The Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) is the most frequently rating scale assessing the efficacy of deep brain stimulation therapy (DBS) for dystonia. To expand our understanding, we evaluated the MCID thresholds for the BFMDRS motor subscale (MS) using physician-reported outcomes. METHODS: We assessed the MCID thresholds for the BFMDRS using movement disorder specialist ratings of videotapes from patients with genetically determined dystonia (Tor1A and THAP1) who underwent bilateral globus pallidum internum (GPi) DBS. We calculated the effect size of the BFMDRS-MS change and determined the MCID thresholds using the Clinical Global Impression of Change (CGIC). RESULTS: Twelve participants with a median age at DBS of 44.5 (range:27-68) had baseline and follow-up BFMDRS-MS with a median post-DBS follow-up of 5.5 years. Based on descriptive analysis, patients with good improvement after DBS according to the CGIC [8/12 (67%)] had a median BFMDRS-MS score reduction of 77% [Interquartile range (IQR):66.2;91.0) with an effect size of 0.39, and those with non-improvement [4/12 (33%)], had a median BFMDRS-MS score reduction of 62% (IQR:36.6;83.6). CONCLUSIONS: Our MCID estimates can be utilized in clinical practice in judging clinical relevance. However, further larger, powered studies are needed to simultaneously determine and compare MCID using patient and physician-reported outcomes in segmental and generalized dystonia in genetic and non-genetic populations.

Surgical Management for Dystonia: Efficacy of Deep Brain Stimulation in the Long Term.

INTRODUCTION: Dystonia is a movement disorder substantially affecting the quality of life. Botulinum Neurotoxin (BoNT) is used intramuscularly as a treatment for dystonia; however, not all dystonia patients respond to this treatment. Deep brain stimulation (DBS) is an established treatment for Parkinson's disease (PD) and essential tremor, but it can help in dystonia as well. OBJECTIVES: We studied a total of 67 dystonia patients who were treated with DBS over a period of 7 years to find out the long-term efficacy of DBS in those patients. First, we calculated patient improvement in post-surgery follow-up programs using the Global Dystonia Severity scale (GDS) and Burke-Fahn-Marsden dystonia rating scale (BFMDRS). Secondly, we analyzed the scales scores to see if there was any statistical significance. METHODS: In our study we analyzed patients with ages from 38 to 78 years with dystonia who underwent DBS surgery between January 2014 and December 2020 in four different centers (India, Kuwait, Egypt, and Turkey). The motor response to DBS surgery was retrospectively measured for each patient during every follow-up visit using the GDS and the BFMDRS scales. RESULTS: Five to 7 years post-DBS, the mean reduction in the GDS score was 30 ± 1.0 and for the BFMDRS score 26 ± 1.0. The longitudinal change in scores at 12 and 24 months post-op was also significant with mean reductions in GDS and BFMDRS scores of 68 ± 1.0 and 56 ± 1.0, respectively. The p-values were <0.05 for our post-DBS dystonia patients. CONCLUSIONS: This study illustrates DBS is an established, effective treatment option for patients with different dystonias, such as generalized, cervical, and various brain pathology-induced dystonias. Although symptoms are not completely eliminated, continuous improvements are noticed throughout the post-stimulation time frame.

Reliability and Validity of the Dyskinesia Impairment Scale in Children and Young Adults with Inherited or Idiopathic Dystonia.

BACKGROUND: The Dyskinesia Impairment Scale (DIS) is a new assessment scale for dystonia and choreoathetosis in children and youth with dyskinetic cerebral palsy. Today, the Burke-Fahn-Marsden Dystonia Rating Scale (BFM) is mostly used to assess dystonia in children with inherited dystonia. The aim of this study was to assess reliability and validity of the DIS in children and youth with inherited or idiopathic dystonia. METHODS: Reliability was measured by (1) the intraclass correlation coefficients (ICCs) for inter-rater and test-retest reliability, as well as (2) standard error of measurement (SEM) and minimal detectable difference (MDD). For concurrent validity of the DIS-dystonia subscale, the BFM was administered. RESULTS: In total, 11 males and 9 females (median age 16 years and 7 months, range 6 to 24 years) were included. For inter-rater reliability, the ICCs for the DIS total score and the dystonia and choreoathetosis subscale scores were 0.83, 0.87, and 0.71, respectively. For test-retest reliability, the ICCs for the DIS total score and the dystonia and choreoathetosis subscale scores were 0.95, 0.88, and 0.93, respectively. The SEM and MDD for the total DIS were 3.98% and 11.04%, respectively. The Spearman correlation coefficient between the dystonia subscale and the BFM was 0.88 (p < 0.01). CONCLUSIONS: Good to excellent inter-rater, test-retest reliability, and validity were found for the total DIS and the dystonia subscale. The choreoathetosis subscale showed moderate inter-rater reliability and excellent test-retest reliability. The DIS may be a promising tool to assess dystonia and choreoathetosis in children and young adults with inherited or idiopathic dystonia.

Pallidal Deep Brain Stimulation in DYT6 Dystonia: Clinical Outcome and Predictive Factors for Motor Improvement.

Pallidal deep brain stimulation is an established treatment in dystonia. Available data on the effect in DYT-THAP1 dystonia (also known as DYT6 dystonia) are scarce and long-term follow-up studies are lacking. In this retrospective, multicenter follow-up case series of medical records of such patients, the clinical outcome of pallidal deep brain stimulation in DYT-THAP1 dystonia, was evaluated. The Burke Fahn Marsden Dystonia Rating Scale served as an outcome measure. Nine females and 5 males were enrolled, with a median follow-up of 4 years and 10 months after implant. All benefited from surgery: dystonia severity was reduced by a median of 58% (IQR 31-62, p = 0.001) at last follow-up, as assessed by the Burke Fahn Marsden movement subscale. In the majority of individuals, there was no improvement of speech or swallowing, and overall, the effect was greater in the trunk and limbs as compared to the cranio-cervical and orolaryngeal regions. No correlation was found between disease duration before surgery, age at surgery, or preoperative disease burden and the outcome of deep brain stimulation. Device- and therapy-related side-effects were few. Accordingly, pallidal deep brain stimulation should be considered in clinically impairing and pharmaco-resistant DYT-THAP1 dystonia. The method is safe and effective, both short- and long-term.

Clinical phenotypes associated with outcomes following deep brain stimulation for childhood dystonia.

OBJECTIVE: Although deep brain stimulation (DBS) is an accepted treatment for childhood dystonia, there is significant heterogeneity in treatment response and few data are available to identify ideal surgical candidates. METHODS: Data were derived from a systematic review and individual patient data meta-analysis of DBS for dystonia in children that was previously published. Outcomes were assessed using the Burke-Fahn-Marsden Dystonia Rating Scale for movement (BFMDRS-M) and for disability (BFMDRS-D). The authors used partial least squares, bootstrapping, and permutation statistics to extract patterns of contributions of specific preoperative characteristics to relationship with distinct outcomes, in all patients and in patients with primary and secondary dystonia separately. RESULTS: Of 301 children undergoing DBS for dystonia, 167 had primary dystonia, 125 secondary dystonia, and 9 myoclonus dystonia. Three dissociable preoperative phenotypes (latent variables) were identified and associated with the following: 1) BFMDRS-M at last follow-up; 2) relative change in BFMDRS-M score; and 3) relative change in BFMDRS-D score. The phenotype of patients with secondary dystonia, with a high BFMDRS-M score and truncal involvement, undergoing DBS at a younger age, was associated with a worse postoperative BFMDRS-M score. Children with primary dystonia involving the trunk had greater improvement in BFMDRS-M and -D scores. Those with primary dystonia of shorter duration and proportion of life with disease, undergoing globus pallidus DBS, had greater improvements in BFMDRS-D scores at long-term follow-up. CONCLUSIONS: In a comprehensive, data-driven, multivariate analysis of DBS for childhood dystonia, the authors identified novel and dissociable patient phenotypes associated with distinct outcomes. The findings of this report may inform surgical candidacy for DBS.

Clinical outcomes of pallidal deep brain stimulation for dystonia implanted using intraoperative MRI.

OBJECTIVE: Lead placement for deep brain stimulation (DBS) using intraoperative MRI (iMRI) relies solely on real-time intraoperative neuroimaging to guide electrode placement, without microelectrode recording (MER) or electrical stimulation. There is limited information, however, on outcomes after iMRI-guided DBS for dystonia. The authors evaluated clinical outcomes and targeting accuracy in patients with dystonia who underwent lead placement using an iMRI targeting platform. METHODS: Patients with dystonia undergoing iMRI-guided lead placement in the globus pallidus pars internus (GPi) were identified. Patients with a prior ablative or MER-guided procedure were excluded from clinical outcomes analysis. Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) scores and Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores were assessed preoperatively and at 6 and 12 months postoperatively. Other measures analyzed include lead accuracy, complications/adverse events, and stimulation parameters. RESULTS: A total of 60 leads were implanted in 30 patients. Stereotactic lead accuracy in the axial plane was 0.93 ± 0.12 mm from the intended target. Nineteen patients (idiopathic focal, n = 7; idiopathic segmental, n = 5; DYT1, n = 1; tardive, n = 2; other secondary, n = 4) were included in clinical outcomes analysis. The mean improvement in BFMDRS score was 51.9% ± 9.7% at 6 months and 63.4% ± 8.0% at 1 year. TWSTRS scores in patients with predominant cervical dystonia (n = 13) improved by 53.3% ± 10.5% at 6 months and 67.6% ± 9.0% at 1 year. Serious complications occurred in 6 patients (20%), involving 8 of 60 implanted leads (13.3%). The rate of serious complications across all patients undergoing iMRI-guided DBS at the authors' institution was further reviewed, including an additional 53 patients undergoing GPi-DBS for Parkinson disease. In this expanded cohort, serious complications occurred in 11 patients (13.3%) involving 15 leads (10.1%). CONCLUSIONS: Intraoperative MRI-guided lead placement in patients with dystonia showed improvement in clinical outcomes comparable to previously reported results using awake MER-guided lead placement. The accuracy of lead placement was high, and the procedure was well tolerated in the majority of patients. However, a number of patients experienced serious adverse events that were attributable to the introduction of a novel technique into a busy neurosurgical practice, and which led to the revision of protocols, product inserts, and on-site training.

Staged bilateral pallidotomy for dystonic camptocormia: case report.

Camptocormia is a rare, involuntary movement disorder, presenting as truncal flexion while standing or walking, and is mainly observed as a feature of Parkinson's disease (PD) and primary dystonia. Deep brain stimulation (DBS) of the globus pallidus internus is effective for refractory camptocormia observed with PD or dystonia. However, the effectiveness of pallidotomy for camptocormia has not been investigated. The authors report the case of a 38-year-old man with anterior truncal bending that developed when he was 36 years old. Prior to the onset of the symptom, he had been taking antipsychotic drugs for schizophrenia. There were no features of PD; the symptom severely interfered with his walking and daily life. He was given anticholinergics, clonazepam, and botulinum toxin injections, which did not result in much success. Because of the patient's unwillingness to undergo implantation of a hardware device, he underwent staged bilateral pallidotomy with complete resolution for a diagnosis of tardive dystonic camptocormia. The Burke-Fahn-Marsden dystonia rating scale subscore for the trunk before and after bilateral pallidotomy was 3 and 0, respectively. No perioperative adverse events were observed. Effects have persisted for 18 months. Bilateral pallidotomy can be a treatment option for medically refractory dystonic camptocormia without the need for device implantation.

Bilateral deep brain stimulation of the subthalamic nucleus in primary Meige syndrome.

OBJECTIVE Subthalamic nucleus deep brain stimulation has been shown to be effective in reducing symptoms of primary Meige syndrome. However, assessments of its efficacy and safety have been limited to several case reports and small studies. METHODS The authors performed a retrospective study to assess the efficacy and safety of bilateral subthalamic nucleus stimulation in 15 patients with primary Meige syndrome who responded poorly to medical treatments or botulinum toxin injections. Using the movement and disability subscores of the Burke-Fahn-Marsden Dystonia Rating Scale, the authors evaluated the severity of patients' dystonia and related before surgery and at final follow-up during neurostimulation. The movement scale was assessed based on preoperative and postoperative video documentation by an independent rater who was unaware of each patient's neurostimulation status. Quality of life was assessed with the Medical Outcomes Study 36-Item Short-Form General Health Survey. RESULTS The dystonia movement subscores in 14 consecutive patients improved from 19.3 ± 7.6 (mean ± standard deviation) before surgery to 5.5 ± 4.5 at final follow-up (28.5 ± 16.5 months), with a mean improvement of 74% (p < 0.05). The disability subscore improved from 15.6 ± 4.9 before surgery to 6.1 ± 3.5 at final follow-up (p < 0.05). In addition, the postoperative SF-36 scores increased markedly over those at baseline. The authors also found that bilateral stimulation of the subthalamic nucleus immediately improved patient symptoms after stimulation and required lower stimulation parameters than those needed for pallidal deep brain stimulation for primary Meige syndrome. Four adverse events occurred in 3 patients; all of these events resolved without permanent sequelae. CONCLUSIONS These findings provide further evidence to support the long-term efficacy and safety of subthalamic nucleus stimulation as an alternative treatment for patients with medically intractable Meige syndrome.

Long-term outcome of pallidal stimulation for Meige syndrome.

OBJECTIVE Meige syndrome is characterized by blepharospasm and varied subphenotypes of craniocervical dystonia. Current literature on pallidal surgery for Meige syndrome is limited to case reports and a few small-scale studies. The authors investigated the clinical outcomes of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in patients with Meige syndrome. METHODS Sixteen patients who underwent GPi DBS at the Tokyo Women's Medical University Hospital between 2002 and 2015 were included in this study. Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) movement subscale (BFMDRS-M) scores (range 0-120) obtained at the following 3 time points were included in this analysis: before surgery, 3 months after surgery, and at the most recent follow-up evaluation. RESULTS The patients' mean age (± SD) at symptom onset was 46.7 ± 10.1 years, and the mean disease duration at the time of the authors' initial evaluation was 5.9 ± 4.1 years. In 12 patients, the initial symptom was blepharospasm, and the other 4 patients presented with cervical dystonia. The mean postoperative follow-up period was 66.6 ± 40.7 months (range 13-150 months). The mean total BFMDRS-M scores at the 3 time points were 16.3 ± 5.5, 5.5 ± 5.6 (66.3% improvement, p < 0.001), and 6.7 ± 7.3 (58.9% improvement, p < 0.001). CONCLUSIONS The results indicate long-term efficacy for GPi DBS for the majority of patients with Meige syndrome.

Frameless robot-assisted pallidal deep brain stimulation surgery in pediatric patients with movement disorders: precision and short-term clinical results.

OBJECTIVE: The purpose of this study was to verify the safety and accuracy of the Neuromate stereotactic robot for use in deep brain stimulation (DBS) electrode implantation for the treatment of hyperkinetic movement disorders in childhood and describe the authors' initial clinical results. METHODS: A prospective evaluation of pediatric patients with dystonia and other hyperkinetic movement disorders was carried out during the 1st year after the start-up of a pediatric DBS unit in Barcelona. Electrodes were implanted bilaterally in the globus pallidus internus (GPi) using the Neuromate robot without the stereotactic frame. The authors calculated the distances between the electrodes and their respective planned trajectories, merging the postoperative CT with the preoperative plan using VoXim software. Clinical outcome was monitored using validated scales for dystonia and myoclonus preoperatively and at 1 month and 6 months postoperatively and by means of a quality-of-life questionnaire for children, administered before surgery and at 6 months' follow-up. We also recorded complications derived from the implantation technique, "hardware," and stimulation. RESULTS: Six patients aged 7 to 16 years and diagnosed with isolated dystonia ( DYT1 negative) (3 patients), choreo-dystonia related to PDE2A mutation (1 patient), or myoclonus-dystonia syndrome SGCE mutations (2 patients) were evaluated during a period of 6 to 19 months. The average accuracy in the placement of the electrodes was 1.24 mm at the target point. At the 6-month follow-up, patients showed an improvement in the motor (65%) and functional (48%) components of the Burke-Fahn-Marsden Dystonia Rating Scale. Patients with myoclonus and SGCE mutations also showed an improvement in action myoclonus (95%-100%) and in functional tests (50%-75%) according to the Unified Motor-Rating Scale. The Neuro-QOL score revealed inconsistent results, with improvement in motor function and social relationships but worsening in anxiety, cognitive function, and pain. The only surgical complication was medial displacement of the first electrode, which limited intensity of stimulation in the lower contacts, in one case. CONCLUSIONS: The Neuromate stereotactic robot is an accurate and safe tool for the placement of GPi electrodes in children with hyperkinetic movement disorders.

The Burke-Fahn-Marsden Dystonia Rating Scale is Age-Dependent in Healthy Children.

BACKGROUND: The Burke-Fahn-Marsden Dystonia Rating Scale is a universally applied instrument for the quantitative assessment of dystonia in both children and adults. However, immature movements by healthy young children may also show "dystonic characteristics" as a consequence of physiologically incomplete brain maturation. This could implicate that Burke-Fahn-Marsden scale scores are confounded by pediatric age. OBJECTIVE: In healthy young children, we aimed to determine whether physiologically immature movements and postures can induce an age-related effect on Burke-Fahn-Marsden movement and disability scale scores. METHODS: Nine assessors specializied in movement disorders (3 adult neurologists, 3 pediatric neurologists, and 3 MD/PhD students) independently scored the Burke-Fahn-Marsden movement scale in 52 healthy children (4-16 years of age; 2 boys and 2 girls per year of age). Independent of that, parents scored their children's functional motor development according to the Burke-Fahn-Marsden disability scale in another 52 healthy children (4-16 years of age; 2 boys and 2 girls per year of age). By regression analysis, we determined the association between Burke-Fahn-Marsden movement and disability scales outcomes and pediatric age. RESULTS: In healthy children, assessment of physiologically immature motor performances by the Burke-Fahn-Marsden movement and disability scales showed an association between the outcomes of both scales and age (until 16 years and 12 years of age, ß = -0.72 and ß = -0.60, for Burke-Fahn-Marsden movement and disability scale, respectively [both P < 0.001]). CONCLUSIONS: The Burke-Fahn-Marsden movement and disability scales are influenced by the age of the child. For accurate interpretation of longitudinal Burke-Fahn-Marsden Dystonia Rating Scale scores in young dystonic children, consideration of pediatric age-relatedness appears advisory.

Neurosurgical treatment for dystonia: long-term outcome in a case series of 80 patients.

INTRODUCTION: In this study, we assessed the outcomes of patients with dystonia who underwent surgery treatment following the same algorithm. PATIENTS AND METHODS: Eighty consecutive patients with dystonia were submitted to neurosurgical management by means of intrathecal pump implantation, pallidotomy or deep brain stimulation (GPi or VIM). These patients included 48 patients with primary dystonia and 32 patients with secondary dystonia. Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was used to access pre- and post-operative outcomes. Patients were followed from 12 to 114 months. RESULTS: Mean improvement in BFMDRS score among patients with PrD was 87.54% and 42.21% for SeD. Hemidystonic patients in both groups (PrD, SeD) showed a mean improvement in BFMDRS of 71.05% with GPiDBS. Patients with SeD due to previous perinatal insults showed a mean improvement in BFMDRS of 41.9%, with better results in purely dyskinetic patients (mean improvement of 61.2%). CONCLUSION: Use of the proposed algorithm facilitated surgical decision planning, which translated in improved diagnostic rates, earlier interventions, appropriate management plans, and outcomes for both groups (PrD, SeD). Therefore, neuroimaging findings had a positive prognostic significance in the response to treatment in patients with primary dystonia compared with patients with secondary dystonia or distortion of basal ganglia anatomy. However, further studies in this line are warranted.