Burke-Fahn-Marsden Dystonia Rating Scale Movement Research Articles

Long-Term Globus Pallidus Internus Deep Brain Stimulation in Pediatric Non-Degenerative Dystonia: A Cohort Study and a Meta-Analysis.

The evidence in the effectiveness of deep brain stimulation in children with medication-refractory non-degenerative monogenic dystonia is heterogeneous and long-term results are sparse. The objective is to describe long-term outcomes in a single-center cohort and compare our results with a meta-analysis cohort form literature. We performed a retrospective single-center cohort study including consecutive pediatric patients with non-degenerative genetic or idiopathic dystonia treated with globus pallidus internus deep brain stimulation at our center and a systematic review and individual-patient data meta-analysis with the same inclusion criteria. The primary outcome was the change from baseline in the Burke-Fahn-Marsden Dystonia Rating Scale-movement (BFMDRS-M) score. The clinical cohort included 25 patients with a mean study follow-up of 11.4 years. The meta-analysis cohort included 224 patients with a mean follow-up of 3 years. Overall, the BFMDRS-M mean improvements at 1 year and at last follow-up were 41% and 33% in the clinical cohort and 58.9% and 57.2% in the meta-analysis cohort, respectively. TOR1A-dystonia showed the greatest and most stable BFMDRS-M improvement in both cohorts at 1 year and at last follow-up (76.3% and 74.3% in the clinical cohort; 69.6% and 67.3% in the meta-analysis cohort), followed by SGCE-dystonia (63% and 63.9% in the meta-analysis cohort). THAP1-dystonia (70.1% and 29.8% in the clinical cohort; 52.3% and 42.0% in the meta-analysis cohort) and KMT2B-dystonia (33.3% and 41.3% in the clinical cohort; 38.0% and 26.7% in the meta-analysis cohort) showed a less pronounced or sustained response. Globus pallidus deep brain stimulation long-term treatment seems effective with a possible gene-specific differential effect. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

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

BackgroundGlobus 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). MethodsA 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. ResultsTwenty 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. ConclusionBoth 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.

The efficacy and safety of nerve loop blocking in the treatment of blepharospasm in Meige syndrome

Objective: To evaluate the efficacy and safety of nerve loop blocking in the treatment of blepharospasm caused by Meige syndrome. Methods: It was a retrospective case series study. Patients with Meige syndrome characterized by blepharospasm or blepharospasm-oromandibular dystonia who underwent nerve loop blocking in the Ophthalmology Department of Henan No. 3 Provincial People's Hospital from April 2018 to January 2020 were included. Before and after surgery, blepharospasm was graded, and the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was used to score the symptoms of ocular and oral dystonia. The improvement rate of ocular spasm was calculated after surgery according to the scores. The postoperative complications were observed. The Wilcoxon rank test was used to compare the BFMDRS movement subscale scores before and after surgery. The independent sample Mann-Whitney U test was used to compare the improvement rates of eye spasm between male and female patients and between patients with and without combined oromandibular dystonia. Results: Among the 199 patients included, 64 (32.2%) were males, and 135 (67.8%) were females, aged 58 (51, 64) years (22-79 years). The postoperative follow-up period was 24 (21, 28) months. Preoperatively, blepharospasm was graded as grade 3 in 12 patients (6.0%) and grade 4 in 187 patients (94.0%), while the postoperative blepharospasm grades were grade 0 in 100 patients (50.3%), grade 1 in 64 patients (32.2%), grade 2 in 31 patients (15.6%), and grade 3 in 4 patients (2.0%). There was statistically significant difference in the BFMDRS scores of ocular dystonia before and after surgery [8.0 (8.0, 8.0) vs. 0.0 (0.0, 1.0); Z=-12.41, P<0.001]. The improvement rate of blepharospasm in all patients was 100% (87.5%, 100%), ranging from 43.8% to 100%, with no statistically significant difference between patients of different genders and between patients with and without combined oral dystonia (both P>0.05). Statistically significant difference existed in the scores of oral dystonia before and after surgery [2.0 (0.5, 4.5) vs. 1.0 (0.5, 2.0); Z=-4.38, P<0.001], with 25 of 65 patients (38.5%) having their oral symptoms improved. Postoperative complications included eyelid valgus (7.5%, 15/199), frontal numbness (100%, 199/199) and tearing (89.9%, 179/199). Conclusion: Nerve loop blocking is a relatively safe and effective method in the treatment of blepharospasm symptoms of Meige syndrome.

Volume of tissue activated within subthalamic nucleus and clinical efficacy of deep brain stimulation in Meige syndrome.

The clinical efficacy of deep brain stimulation (DBS) relies on the optimal electrode placement in a large extent. Subthalamic nucleus (STN) DBS was recognized as clinically effective for Meige syndrome. This study identified the correlations of volume of tissue activated (VTA) within the motor STN and the final efficacy of the surgical procedure. Clinical outcomes of the patients (n=25) were evaluated with the percentage improvement in Burke-Fahn-Marsden Dystonia Rating Scale movement (BFMDRS-M) scores at the last follow-up (LFU) visit. Pearson's correlation coefficients were calculated to identify the relationship of the final clinical outcomes with the VTA within the STN, VTA within the different STN territories, and other clinical variables. On the whole, the patients showed an average of 59.21% improvement at the LFU visit relative to the baseline (5.72 ± 7.31 vs. 13.70 ± 7.36, P ˂ 0.001). Active electrode contacts mainly clustered in the STN motor territories. There were significant positive correlations between the BFMDRS-M percentage improvement and VTA within the STN (Pearson r = 0.434, P = 0.039) and the STN motor territories (r = 0.430, P = 0.041), but not associative or limbic STN. Other basic clinical characteristics including age, disease duration, and preoperative scores were not significantly correlated with the final outcomes. Our study further validated the efficacy of STN-DBS in even the cases with intractable Meige syndrome. Furthermore, VTA within the motor STN could serve as a potential prognostic factor for the final clinical outcomes.

Outcomes of pallidal deep brain stimulation for treating pure blepharospasm

Objective: Blepharospasm (BSP) is a disease in which the closure rate of the bilateral eyelids increases, mainly due to involuntary contraction of the orbicularis oculi, procerus, and corrugator muscles. The objective of this study was to report postoperative outcomes after deep brain stimulation (DBS) in 10 cases of pure BSP after at least 12 months of follow-up.Methods: Ten patients with pure BSP who underwent bilateral globus pallidus interna (GPi) DBS at The Catholic University of Korea, Incheon St. Mary’s Hospital, between 2019 and 2021 were included. The Burke-Fahn-Marsden dystonia rating scale (BFMDRS), Blepharospasm Disability Index, and Jankovic Rating Scale were used for analysis before surgery, at 6 months of follow-up as short-term outcomes, and at follow-up over 1 year (12–37 months) as long-term results. Results: The median age of patients at surgery was 56.5 years (interquartile range [IQR], 50.5–65.8 years) and the median length of time from disease onset to the time of surgery was 58.0 months (IQR, 46.8–64.3 months). The median postoperative follow-up period was 22.5 months (IQR, 15.3–29.0 months). The median BFMDRS movement subscale scores at the three time points (preoperative baseline, 6 months, and over 1 year of follow-up) were 7.0 (IQR, 6.0–8.0), 4.5 (IQR, 3.9–6.0; 35.7% improvement, p&lt;0.001), and 3.8 (IQR, 2.8–5.3; 45.7% improvement, p=0.002), respectively.Conclusion: Bilateral GPi DBS for pure BSP can be effective if conservative treatment options fail. Its benefit is not only observed in the short term, but is also maintained during long-term follow-up.

Metabolic Imaging of Deep Brain Stimulation in Meige Syndrome.

ObjectivesThe subthalamic nucleus (STN) has been shown to be a safe and effective deep brain stimulation (DBS) surgical target for the treatment of Meige syndrome. The aim of this study was to compare changes in brain metabolism before and 6 months after STN-DBS surgery.MethodsTwenty-five patients with primary Meige syndrome underwent motor function assessment, including the Burke–Fahn–Marsden Dystonia Rating Scale movement (BFMDRS-M) and disability subscale (BFMDRS-D) and positron emission tomography with an 18[F]-fluorodeoxyglucose scan before and 6 months after STN-DBS surgery. For the voxelwise metabolic change assessment, the p-value was controlled for multiple comparisons using the familywise error rate.ResultsThere was a significant decrease in BFMDRS-M scores 6 months after STN-DBS, from 10.02 ± 3.99 to 4.00 ± 2.69 (p < 0.001). The BFMDRS-D scores also decreased significantly from 4.52 ± 2.90 to 0.64 ± 1.29 (p < 0.001). In the left hemisphere, hypermetabolism was found in the occipital lobe, superior parietal gyrus, postcentral gyrus and thalamus. In the right hemisphere, hypermetabolism was found in the lentiform nucleus, precuneus and precentral gyrus in patients with Meige syndrome receiving DBS. In addition, the bilateral inferior temporal gyrus and middle frontal gyrus exhibited glucose hypermetabolism.ConclusionOur findings indicate that STN-DBS has a significant effect on metabolic level in the brain, which may be an important mechanism for the treatment of Meige syndrome using STN-DBS.

GPi-DBS for KMT2B-Associated Dystonia: Systematic Review and Meta-Analysis.

Early evidence suggests good response to pallidal deep brain stimulation (DBS) in DYT-KMT2B. We aimed to conduct a systematic review and meta-analysis to assess outcomes and identify predictors of good outcome following GPi-DBS in DYT-KMT2B. We searched MEDLINE, Cochrane and MDS-abstracts databases using the MeSH terms "KMT2B and DYT28". We included studies that reported objective outcomes following GPi-DBS in DYT-KMT2B. The BFMDRS-M (Burke-Fahn-Marsden Dystonia Rating Scale- Movement) total scores pre- and post-surgery were used to quantify outcomes. We calculated pooled effects using a random effects meta-analysis and used meta-regression to identify potential effect modifiers. Multiple linear regression using individual patient data was used to identify predictors of good outcome (>50% improvement from baseline on BFMDRS-M). Initial searches screened 132 abstracts of which 34 full-text articles were identified to be of potential interest. Ten studies reporting 42 individual patients, met the inclusion/exclusion criteria and were included in the final review. The mean age at onset was 6.4 ± 5.7 years and 40% were male. The median follow-up was 12months (range: 1-264months). GPi-DBS resulted in median BFMDRS-M improvement of 42.7% (range: -103.5% to 95.9%) postoperatively. Pooled proportion of patients experiencing clinical improvement >50% on BFMDRS-M was 41% (95% CI: 27%-57%). Male gender [β: 22.6, 95% CI: 8.0-37.3, P=0.004), and higher pre-operative BFMDRS-M score [β: 0.62, 95% CI: 0.36-0.87, P < 0.001) were independently associated with better outcome. KMT2B-associated dystonia responds effectively to pallidal stimulation. The outcome is better in males and those with more severe dystonia at baseline.

Efficacy and safety of general anesthesia deep brain stimulation for dystonia: an individual patient data meta-analysis of 341 cases.

The efficacy and safety of deep brain stimulation (DBS) under general anesthesia for the treatment of dystonia have not yet been confirmed with high level of evidence. This meta-analysis with pooled individual patient data aims to assess the clinical outcomes and identify the potential prognostic factors of dystonia patients who underwent general anesthesia DBS. We searched PubMed, Web of Science, and Embase for articles describing patients with dystonia who underwent asleep DBS and had individual Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) scores. The relative improvement in BFMDRS scores was considered the primary outcome. Pearson correlation analyses and multivariate linear regression analysis were conducted to explore the prognostic factors. A total of 34 studies involving 341 patients were included. The mean postoperative improvement in BFMDRS-M (BFMDRS movement subscale) and BFMDRS-D (BFMDRS disability subscale) scores were 58.6±36.2% and 48.5±38.7% at the last follow-up visit, respectively, with a mean follow-up time of 22.4±27.6 months. Age at surgery and disease duration showed a negative correlation with the percent improvement of BFMDRS-M (%) at the last visit (r=-0.134, P=0.013; r=-0.165, P=0.006). In the stepwise multivariate regression, only disease duration remained a relevant factor. Additionally, the adverse events were acceptable. General anesthesia DBS is a safe, effective, and feasible option for dystonia patients in the long term. Shorter disease duration predicts better clinical outcomes.

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.

Subthalamic Nucleus Deep Brain Stimulation in Primary Meige Syndrome: A 1-Year Follow-Up Study

ObjectiveTo investigate the efficacy of bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) in patients with Meige syndrome. Materials and MethodsFifteen consecutive patients who underwent STN-DBS at the Peking University People’s Hospital between September 2017 and June 2018 were included in this study. The Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS) movement score and the BFMDRS disability score were obtained prior to surgery, and at specific time points after surgery. Patients’ sleep status was also assessed before and after surgery. ResultsThe BFMDRS movement scores decreased from 15.3 ± 4.6 to 5.2 ± 6.2 after STN-DBS, with a mean improvement of 68.6% (p < 0.05). The BFMDRS disability scores were also significantly decreased, from 6.9 ± 3.3 to 3.5 ± 2.9, with a mean improvement of 51.7% (p < 0.05). The eye, mouth, speech, and swallowing movement scores also decreased significantly after STN-DBS compared to baseline (p < 0.05). The sleep quality of the patients was also improved after surgery. ConclusionsThese findings demonstrate that the STN is an effective brain target for the treatment of patients with Meige syndrome. STN-DBS was not only able to improve patients’ motor symptoms, but also their sleep status.

Pallidal deep brain stimulation in primary Meige syndrome: clinical outcomes and psychiatric features

ObjectivesTo study the efficacy and safety of bilateral globus pallidus internus deep brain stimulation (GPi-DBS) in refractory Meige syndrome (MS) and evaluate the psychiatric disorders before and after surgery.MethodsTwenty-two patients...

Deep brain stimulation for myoclonus dystonia syndrome: a meta-analysis with individual patient data.

Good outcomes have been reported in deep brain stimulation (DBS) for myoclonus-dystonia syndrome (M-D), a heritable disease characterized by childhood-onset myoclonic jerks and dystonia in the upper body. This meta-analysis was to evaluate the clinical outcomes consecutively, compare the stimulation targets, and identify potential prognostic factors. A systematic literature search was performed on PubMed, Web of Science, and Embase. The primary outcome was the percent improvement in Burke-Fahn-Marsden Dystonia Rating Scale movement (BFMDRS-M) scores for dystonia and Unified Myoclonus Rating Scale (UMRS) scores for myoclonus at the last follow-up visit. BFMDRS-disability scores of the patients were also summarized. Pearson correlation analyses were performed to identify the myoclonus and dystonia outcome predictors. Thirty-one studies reporting 71 patients were included. There were significant improvements in BFMDRS-M and BFMDRS-disability scores in each time category and at the last follow-up visit. Mean improvement (%) in UMRS was 79.5 ± 18.2, and 94.1% of the patients showed > 50% improvement in UMRS scores at the last follow-up visit. There was a significant trend toward improved myoclonus outcome with older age at onset and shorter disease duration. Most of the adverse events were mild and transient, and pallidal stimulation seemed to be better with respect to fewer stimulation-induced events. Based on the current data, DBS is effective for even the severe M-D. Surgery at an early stage may predict a better outcome. Although targets do not serve as the outcome predictors, pallidal stimulation may be preferred due to fewer stimulation-induced events.

Deep brain stimulation for Meige syndrome: a meta-analysis with individual patient data.

Deep brain stimulation (DBS) is an effective intervention for Meige syndrome, a type of dystonia characterized by blepharospasm, facial, and oromandibular dystonia. This individual patient-level data meta-analysis was to identify the potential outcome predictors, compare the stimulation targets and summarize the efficacy of DBS for Meige syndrome. Three electronic databases (PubMed, Web of Science and Embase) were searched with no publication data restriction to identify studies regarding DBS for Meige syndrome. The primary outcome was the improvement in BFMDRS-M score. Pearson's correlation coefficients and a stepwise multivariate regression analysis were used to identify the potential prognostic factors. Twenty-three studies (115 patients, 94 with pallidal stimulation and 21 with subthalamic stimulation) were eligible. Patients showed significant improvement in Burke-Fahn-Marsden Dystonia Rating Scale movement (BFMDRS-M) (21.5 ± 11.0 vs 8.6 ± 6.9, P < 0.001) and disability (BFMDRS-D) (6.4 ± 5.1 vs 2.9 ± 2.4, P < 0.001) scores at the last follow-up visit (31.9 ± 30.7months), compared with scores at baseline. Preoperative BFMDRS-M and BFMDRS-D scores were positively correlated with the relative changes in BFMDRS-M score at the last follow-up visit. On the stepwise multivariate regression, only the preoperative BFMDRS remained significant in the best predictive model. Based on the existing evidence, pallidal/subthalamic stimulation is an effective therapy for even the refractory Meige syndrome. Higher preoperative scores probably indicate larger improvement. Stimulation targets or other clinical factors do not constitute the outcome predictive factors.

Comparison of Short-Term Stimulation of the Globus Pallidus Interna and Subthalamic Nucleus for Treatment of Primary Dystonia

To compare the efficacy and side effects of bilateral globus pallidus internus (GPi) and subthalamic nucleus (STN) deep brain stimulation (DBS) in the same patient with primary dystonia. Patients with primary dystonia from the department of functional neurosurgery in Beijing Tiantan Hospital were recruited for the study. Four electrodes were bilaterally implanted in the GPi and STN. A trial stimulation was applied to determine the preliminary therapeutic effects. Five evaluations were conducted: preoperative, postoperative (before stimulation), after sham stimulation, and after stimulation for 24 hours of GPi and STN using optimal parameters, judged by the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). The BFMDRS movement score decreased after both short-term GPi stimulation (from 15.3 ± 6.9 to 7.6 ± 4.2, P < 0.05) and short-term STN stimulation (from 15.3 ± 6.9 to 8.6 ± 5.0, P < 0.05). There were significant reductions in facial (eyes and mouth) movement scores after short-term GPi and STN DBS compared with baseline (P < 0.05), but not in cervical symptoms (P > 0.05). The cervical symptoms of tonic dystonia had an improvement after long-term DBS treatment (P < 0.05). There were more adverse events with STN DBS; however, most side effects could be ameliorated by adjusting stimulation parameters. Both short-term GPi and STN stimulation improved the motor symptoms of dystonia, but there was no significant difference between GPi DBS and STN DBS. There were more side effects associated with STN stimulation.

The long-term efficacy of deep brain stimulation for medically refractory primary generalized dystonia

Objective To evaluate the long-term efficacy of deep brain stimulation (DBS) in treatment of medically refractory primary generalized dystonia (PGD) and to compare the effect of stimulation of subthalamic nucleus (STN) with that of globus pallidus internus (GPi) in the treatment of dystonia. Methods Twenty-one cases of PGD underwent STN-DBS or GPi-DBS at Department of Neurosurgery, Tangdu Hospital, the Fourth Military Medical University from December 2004 to April 2013 and were enrolled into this study. Among them, 11 patients underwent STN stimulation (STN-DBS group) and the other 10 cases received GPi stimulation (GPi-DBS group). Pre- and postoperative severity of dystonia were assessed by using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). Results The average improvement rates of BFMDRS movement subscale in the 21 cases of PGD were 63.7±14.2 % and 66.5±13.7 % at 1 and 3 years post operation, respectively. Meanwhile, the disability scores were reduced by 43.7±13.8 % and 49.1±12.4 %, respectively. The movement scores in STN-DBS group were 56.9±20.9 prior to surgery and 18.3±6.8 at 3 years post operation, and the average improvement rate was 64.6±15.2 %. Their disability scores were 20.0(11.0) prior to surgery and 8.0(4.0) points at 3 years post operation, and the average improvement rate was 54.5 %(15.0 %). In the GPi-DBS group, the movement scores were 60.8±19.3 before surgery and 18.3±7.9 at 3 years post surgery, and the average improvement rate was 68.6±12.5 %. Their disability scores were 17.5±5.4 before surgery and 8.9±2.5 post surgery, and the average improvement rate was 47.2±12.8 %. There was no statistically significant difference in the improvement rates of BFMDRS movement and disability scores between 2 targets at 1 year and 3 years after surgery (both P>0.05). Conclusions The effect of DBS in the treatment of medically refractory seems to be significant and sustained. Our preliminary results suggest that there is no significant difference in the long-term efficacy between stimulation of STN and stimulation of GPi for dystonia. Key words: Deep brain stimulation; Subthalamic nucleus; Globus pallidus; Primary dystonia; Treatment outcome

Treatment of generalized dystonia by deep brain stimulation

Objective To evaluate the efficacy of deep brain stimulation in treatment of generalized dystonia. Methods A retrospective analysis was conducted on 20 patients who were implanted with a PINS device at Department of Neurosurgery, Peking Union Medical College Hospital from July 2013 to September 2016. Among them, 13 cases were primary generalized dystonia and 7 cases had secondary generalized dystonia. The scores of Burke-Fahn-Marsden dystonia movement/disability were documented at baseline and at 3, 6, 12 months of follow-up. The rate of improvement was assessed at 12 months postoperatively to evaluate the effectiveness of the PINS DBS system. Comparison was conducted regarding the improvement of scores between groups with different targets and parameters of stimulation. Results Compared with preoperative state, the improvement rates of median BFMDRS-M (Burke-Fahn-Marsden Dystonia Rating Scale-Movement) scores were 86.1% and 43.9% in patients with primary and secondary systemic dystonia at 12 months post surgery, respectively. The improvement rates of median BFMDRS-D (Burke-Fahn-Marsden Dystonia Rating Scale-Disability) scores were 66.7% and 44.4%, respectively, and there was significant difference between pre- and post-operative states (both P 0.05). However, the stimulation parameters of STN-DBS group were significantly lower than those of GPi-DBS group (all P<0.05) in terms of voltage, frequency and amplitude. The follow-up lasted 12-48 months. Only 2 cases developed dyskinesia as the adverse event which resolved or obtained improvement by the end of the study. No adverse effects were classified as severe. Conclusions The deep brain stimulation system domestically manufactured could significantly improve the symptoms of generalized dystonia and demonstrates safety and effectiveness. Key words: Deep drain stimulation; Generalized dystonia; Treatment outcome

Subthalamic Nuclei Stimulation in Patients With Pantothenate Kinase-Associated Neurodegeneration (PKAN)

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive genetic disease that leads to extrapyramidal symptoms, such as dystonia, ataxia, dysarthria, and involuntary movements. Treatment of PKAN with deep brain stimulation (DBS) has been reported, but mainly focuses on targeting the globus pallidus internus (GPi). Subthalamic nuclei (STN) may also be a potential target for treatment of PKAN. In this study, we reviewed three patients with PKAN (two with typical PKAN and one with atypical PKAN) treated by bilateral STN stimulation and present a review of the literature. All patients received neurological evaluation using the Burke-Fahn-Marsden Dystonia Rating Scale-movement (BFMDRS) scoring system before and after surgery. Patients were then subject to regular clinical follow-ups (ranging from 22 to 44 months). The mean stimulation amplitude, pulse width and frequency was 2.65 ± 0.45 V, 91.7 ± 21.9 μs, and 146.7 ± 12.5 Hz, respectively. BFMDRS scores were improved in all patients after surgery, ranging from 41.6 to 73.1%. Improvements of appendicular symptoms ranged from 46.2 to 94.1%, and improvements of axial symptoms ranged from 27.3 to 33.3%. No side effects were reported in patients 1 and 2; whereas patient 3 exhibited a mild decline in verbal fluency one year after surgery. STN stimulation could serve as a candidate DBS target in the treatment of PKAN, especially for patients with prominent appendicular symptoms.

Burke-Fahn-Marsden dystonia severity, Gross Motor, Manual Ability, and Communication Function Classification scales in childhood hyperkinetic movement disorders including cerebral palsy: a 'Rosetta Stone' study.

Hyperkinetic movement disorders (HMDs) can be assessed using impairment-based scales or functional classifications. The Burke-Fahn-Marsden Dystonia Rating Scale-movement (BFM-M) evaluates dystonia impairment, but may not reflect functional ability. The Gross Motor Function Classification System (GMFCS), Manual Ability Classification System (MACS), and Communication Function Classification System (CFCS) are widely used in the literature on cerebral palsy to classify functional ability, but not in childhood movement disorders. We explore the concordance of these three functional scales in a large sample of paediatric HMDs and the impact of dystonia severity on these scales. Children with HMDs (n=161; median age 10y 3mo, range 2y 6mo-21y) were assessed using the BFM-M, GMFCS, MACS, and CFCS from 2007 to 2013. This cross-sectional study contrasts the information provided by these scales. All four scales were strongly associated (all Spearman's rank correlation coefficient rs >0.72, p<0.001), with worse dystonia severity implying worse function. Secondary dystonias had worse dystonia and less function than primary dystonias (p<0.001). A longer proportion of life lived with dystonia is associated with more severe dystonia (rs =0.42, p<0.001). The BFM-M is strongly linked with the GMFCS, MACS, and CFCS, irrespective of aetiology. Each scale offers interrelated but complementary information and is applicable to all aetiologies. Movement disorders including cerebral palsy can be effectively evaluated using these scales.

Same same but different: analyzing hyperkinetic movement disorders.

This commentary is on the original article by Elze et al. on pages 145–153 of this issue. In their current study, Elze et al.1 have analysed a heterogeneous group of individuals with a common problem: hyperkinetic movement disorder. Is it possible to do that? What are the challenges and pitfalls of such a venture? You may say that two conceptual worlds meet in this paper: the knowledge and terminology of the movement disorder world on one hand and that of cerebral palsy (CP) on the other hand. There is an abundance of descriptive terms and classifications regarding movement disorders in general, not least in the CP literature.2, 3 The paper by Elze et al. illustrates this also. And some terms, such as ‘hyperkinetic’, may have a different meaning depending on which world you come from. One challenge is the different conditions behind the dystonia, dyskinesia, or hyperkinetic movement disorder. A variety of accompanying impairments will affect communication and motor function and performance that are classified with the instruments used in this study. Stationary or progressive courses, age at onset, and localization and extension of brain lesions are other issues to consider in the evaluation of an individual with a hyperkinetic movement disorder. The Burke–Fahn–Marsden Dystonia Rating Scale-movement is developed for primary dystonia. In the present study the dystonia severity subscale was used, which has a good reliability in CP according to a study by Monbaliu et al.4 However, a new instrument, the Dyskinesia Impairment Scale has been developed by the same group and a study on functional profiles in dyskinetic CP has recently been published in DMCN.5 The associations found between severity of dystonia and functional profiles are quite similar when comparing the study by Elze et al. and the study by Monbaliu et al. An effort to overcome the differences, focusing on a common problem, and reaching an understanding (while perhaps not speaking the same ‘language’) is a welcome effort. The present study by Elze et al. comes from the perspective of a specialist movement disorder service. Still, the associations found in this convenience sample are interesting. Although validity and reliability studies of the classification systems used are missing for part of the present study population, functional assessment and profiling should be pursued. Sharing the views and actions of the two worlds would benefit the individual with hyperkinetic movement disorder. The use of classifications developed for individuals with CP may help to map the functional profile of individuals with primary dystonia. As Elze et al. point out, there may be non-motor consequences in this group that are not yet identified. On the other hand, for individuals with secondary dystonia (e.g. dyskinetic CP), interventions that have been considered mainly for those with primary dystonia before, may be more available if the focus is on the movement disorder, regardless of aetiology. Indeed the different terminologies will need a ‘Rosetta stone’ of their own (as Elze et al. suggest) or risk being lost in translation.

Long-term follow-up study on deep brain stimulation for post-traumatic dystonia

Background Deep brain stimulation (DBS) offers a very promising therapy for medically intractable dystonia. Among different dystonia subtypes, the surgical outcome of primary dystonia is most convincing, while that of post-traumatic dystonia is uncertain. This paper aims to evaluate the effect of DBS on post-traumatic dystonia. Methods Four patients of post-traumatic dystonia treated with DBS on globus pallidus internus (GPi) or subthalamic nucleus (STN) were reviewed and their surgical effect was evaluated. Outcome assessments were based on Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) movement and disability scores preoperatively and one month, 6 months, one year and 2 years after surgery. Improvement rate was counted to evaluate the curative effect. Results BFMDRS movement scores were improved by 38.35%, 47.28%, 62.74% and 68.69% respectively, and disability scores were improved by 35.36% , 46.83% , 59.60% and 67.01% respectively. Imaging features of these patients were reviewed. Although the location and size of encephalomalacia differed among these patients, the anatomical features of basal ganglia remained intact. Conclusions With strict selection, DBS may be a promising treatment to ameliorate the symptoms of post-traumatic dystonia. The surgical effect may be sustainable in long term. Anatomical integrity of basal ganglia may be an important factor to predict good outcome. DOI: 10.3969/j.issn.1672-6731.2015.10.006