Bilateral Pallidal Stimulation Research Articles

Bilateral Pallidal Deep Brain Stimulation in Meige Syndrome: Effects on Motor Function, Neuropsychological Status, and Mood.

Bilateral pallidal deep brain stimulation (DBS) has been broadly accepted as a feasible surgical procedure for treating various forms of dystonia, but its effects on motor function, neuropsychological status, and mood in patients with Meige syndrome have rarely been examined. To evaluate the effects of bilateral globus pallidus internus DBS (GPi-DBS) on the motor performance, quality of life, neuropsychological status, and mood of patients with primary Meige syndrome. Between January 2015 and April 2019, the database of 35 patients with Meige syndrome who underwent bilateral GPi-DBS in our institution was retrospectively reviewed. The severity of dystonia, health-related quality of life, cognitive function, and mood were assessed using standardized and validated rating scales at baseline. Repeat assessment of the same domains was performed at 1 year and 3 years after neurostimulation in a similar manner. One year and 3 years after bilateral GPi-DBS, Burke-Fahn-Marsden Dystonia Rating Scale movement scores were improved by 65% and 72% and Burke-Fahn-Marsden Dystonia Rating Scale disability scores were improved by 49% and 57%, respectively. The significant improvement in health-related quality of life observed at 1 year was sustained at 3 years. Relative to baseline and to the 1-year assessment, cognitive functions and mood remained stable after 3 years of neurostimulation. No deaths or life-threatening events were reported over the study period. Bilateral GPi-DBS is a safe and effective approach for medically refractory Meige syndrome that can improve motor function and quality of life without cognitive and mood side effects.

Does Pallidal Physiology Determine the Success of Unilateral Deep Brain Stimulation in Cervical Dystonia?

Pallidal deep brain stimulation is a well-known surgical treatment for cervical dystonia. The resolution of dystonia typically requires bilateral pallidal stimulation, but in some instances, unilateral stimulation has been successful. In such instances, generally, the stimulated hemisphere was contralateral to the dystonic sternocleidomastoid, but rarely it was ipsilateral. We sought for the physiological features that determine the basis for success and laterality of deep brain stimulation for cervical dystonia with prominent torticollis. We found that pallidal physiology such as high burst to tonic ratio and significant interhemispheric differences in the neuronal firing rate and regularity are critical determinants of successful treatment with unilateral deep brain stimulation. We also found that higher lateralized differences in pallidal physiological parameters predict more robust improvement. In three out of four patients, the stimulation of the hemisphere ipsilateral to the dystonic sternocleidomastoid muscle was effective. These patients did not have any structural brain abnormalities on clinically available imaging studies. One patient responded to the unilateral deep brain stimulation in the hemisphere contralateral to the dystonic sternocleidomastoid. This patient had a structural putamen lesion on brain MRI. These results provide objective parameters determining the success of pallidal deep brain stimulation for treatment of cervical dystonia. The results also depict differences in the pallidal physiology in patients where ipsilateral versus contralateral deep brain stimulation was effective.

Bilateral Pallidal Stimulation in a Family With Myoclonus Dystonia Syndrome Due to a Mutation in the Sarcoglycan Gene

ObjectivesThe study aimed to present a family with myoclonus dystonia (M-D) syndrome due to a mutation in the epsilon sarcoglycan gene (SGCE). Three members of the family suffered from treatment-refractory severe myoclonic jerks of the neck, trunk, and upper extremities. The mild dystonic symptoms recognized as cervical dystonia or truncal dystonia affected all individuals. The efficacy of pharmacotherapy, including anticholinergic, dopaminergic, and serotoninergic drugs, has failed. One individual developed an alcohol dependency and suffered from alcoholic epilepsy. Materials and MethodsThe patients were referred for stereotactic surgery. All individuals underwent bilateral implantation of deep brain stimulation (DBS) leads into the posteroventrolateral segment of the globus pallidus internus (GPi). Surgeries were uneventful. The formal preoperative objective assessment included the Unified Myoclonus Rating Scale (UMRS) and the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). The postoperative UMRS and BFMDRS assessments were done only under continuous stimulation at 3, 6, and 12 months after the surgery and at the last available follow-up ranging from 6 to 15 months (mean, 10 months follow-up). ResultsAt the last follow-up visit, the rest and action parts of UMRS were improved by 93.3% and 88.2%, respectively, when compared to the baseline scores. The motor and disability scales of BFMDRS were improved by 77% and 43% at the last follow-up visit compared to the baseline BFMDRS scores. There were no hardware or stimulation-induced complications over the follow-up period. Positive social adjustment allowed two patients to regain jobs and one patient continued his education and hobbies. ConclusionOur experience gathered in three individuals in the family with a mutation in SGCE indicates that bilateral GPi DBS can be an effective and safe treatment for disabling pharmacological resistant, intractable M-D syndrome.

Marie Vidailhet: recognising the importance of teamwork

The city of Toulouse in southern France is filled with a rich history of heroes, adventure, and challenges; where Concorde made its first test flight and the French National Centre for Space Studies obtained stunning satellite images of Earth. It is also the birthplace of Marie Vidailhet, professor of neurology and head of the Movement Disorders and Parkinson's Disease department at the Salpêtrière Hospital—the “cradle of neurology” in France (Sorbonne University, Paris). Bilateral, pallidal, deep-brain stimulation in primary generalised dystonia: a prospective 3 year follow-up studyBilateral pallidal stimulation provides sustained motor benefit after 3 years. Mild long-term improvements in quality of life and attention were also observed. Full-Text PDF Bilateral pallidal deep brain stimulation for the treatment of patients with dystonia-choreoathetosis cerebral palsy: a prospective pilot studyBilateral pallidal neurostimulation could be an effective treatment option for patients with dystonia-choreoathetosis CP. However, given the heterogeneity of motor outcomes and the small sample size, results should be interpreted with caution. The optimum placement of the leads seemed to be a crucial, but not exclusive, factor that could affect a good outcome. Full-Text PDF

Long-Term Follow-Up of 12 Patients Treated with Bilateral Pallidal Stimulation for Tardive Dystonia.

Tardive dystonia (TD) is a side effect of prolonged dopamine receptor antagonist intake. TD can be a chronic disabling movement disorder despite medical treatment. We previously demonstrated successful outcomes in six patients with TD using deep brain stimulation (DBS); however, more patients are needed to better understand the efficacy of DBS for treating TD. We assessed the outcomes of 12 patients with TD who underwent globus pallidus internus (GPi) DBS by extending the follow-up period of previously reported patients and enrolling six additional patients. All patients were refractory to pharmacotherapy and were referred for surgical intervention by movement disorder neurologists. In all patients, DBS electrodes were implanted bilaterally within the GPi under general anesthesia. The mean ages at TD onset and surgery were 39.2 ± 12.3 years and 44.6 ± 12.3 years, respectively. The Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS) performed the preoperative and postoperative evaluations. The average BFMDRS improvement rate at 1 month postoperatively was 75.6 ± 27.6% (p < 0.001). Ten patients were assessed in the long term (78.0 ± 50.4 months after surgery), and the long-term BFMDRS improvement was 78.0 ± 20.4%. Two patients responded poorly to DBS. Both had a longer duration from TD onset to surgery and older age at surgery. A cognitive and psychiatric decline was observed in the oldest patients, while no such decline ware observed in the younger patients. In most patients with TD, GPi-DBS could be a beneficial therapeutic option for long-term relief of TD.

Case Report: Globus Pallidus Internus (GPi) Deep Brain Stimulation Induced Keyboard Typing Dysfunction.

Introduction:Typing on a keyboard requires complex collaboration between visuospatial/procedural memory, language, and motor function. The impaired ability to type, independent of motor deficits, apraxia, or aphasia has been coined “dystypia.”Case Presentation: A 68-year-old woman with a history of blepharospasm, oromandibular, and segmental dystonia underwent bilateral pallidal deep brain stimulation (DBS) because of a waning response to botulinum toxin therapy. Following DBS, she discovered she no longer “remembered” how to type fluidly and had to “hunt and peck” for letters on the keyboard. This issue persisted at a 2-year follow-up. The patient underwent serial typing tests with the DBS ON vs. OFF. Post-operative lead reconstruction was performed using Lead-DBS. The volume of tissue activation (VTA) modeling was combined with whole-brain tractography.Results: Typing improved when the device was switched to the DBS OFF state. Cortical mapping revealed strong modulation of the right angular gyrus, left calcarine fissure, and left cuneus. There was also activation of bilateral supplemental motor areas and superior parietal gyri.Discussion: Shared lesion topography analysis of dystypia cases in the literature has suggested the involvement of the superior longitudinal fasciculus (SLF). The SLF involves the superior parietal lobe, angular gyrus, supramarginal gyrus, and arcuate fasciculus. Our patient’s connectivity pattern suggested SLF involvement. The improvement in OFF state typing and her imaging together suggested that the dystypia in her case was a stimulation-induced side effect.Conclusion: Dystypia is a rare side effect of Globus Pallidus Internus (GPi) DBS therapy and may be associated with SLF involvement.

Bilateral pallidal stimulation improves cervical dystonia for more than a decade

IntroductionDeep brain stimulation (DBS) is an effective treatment in medically resistant cervical dystonia (CD) with a documented therapeutic effect. Long term outcome beyond a decade, however, has not been studied systematically. MethodsTo investigate the impact of pallidal DBS beyond 10 years in CD we followed a series of five consecutive patients with severe medication-resistant CD. Severity of head and neck deviation, disability, and pain related to dystonia were assessed by the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) in the frame of a prospective study. The primary endpoint of this study was a change in the TWSTRS total score. Secondary endpoints were changes in the subscores of the TWSTRS. ResultsThe mean follow-up time was 11.5 years (range 10–12.8). Comparing baseline and the last follow-up, CD improved by 53% on the total TWSTRS score, by 54.1% on the severity score, and by 70.1% on the disability score, while pain did not improve significantly. Improvement was stable over time. Patients with a tonic pattern of CD responded less to DBS than patients with a phasic pattern. DBS had no significant effect on mood and cognition. Two patients underwent electrode revisions. One patient had an infection of the proximal cable two years after surgery. ConclusionsChronic bilateral pallidal stimulation improves severity of dystonia and disability over more than a decade in treatment resistant CD. Results may vary among individual patients.

Long-term effects of bilateral pallidal deep brain stimulation in dystonia: a follow-up between 8 and 16\xa0years

ObjectiveObservational study to evaluate the long-term motor and non-motor effects of deep brain stimulation (DBS) of the globus pallidus internus (GPi) on medically refractory dystonia.BackgroundDystonia is a chronic disease affecting mainly young patients with a regular life expectancy and lifelong need for therapy. Pallidal DBS is an established treatment for severe isolated dystonia but long-term data are sparse.MethodsWe considered 36 consecutive patients with isolated generalized (n = 14) and cervical/segmental (n = 22) dystonia operated at Charité-University Hospital between 2000 and 2007 in a retrospective analysis for long-term outcome of pallidal DBS. In 19 of these patients, we could analyze dystonic symptoms and disability rated by the Burke–Fahn–Marsden Dystonia Rating scale (BFMDRS) at baseline, short-term (ST-FU, range 3–36 months) and long-term follow-up (LT-FU, range 93–197 months). Quality of life and mood were evaluated using the SF36 and Beck Depression Index (BDI) questionnaires.ResultsPatients reached an improvement in motor symptoms of 63.8 ± 5.7% (mean ± SE) at ST-FU and 67.9 ± 6.1% at LT-FU. Moreover, a significant and stable reduction in disability was shown following DBS (54.2 ± 9.4% at ST-FU and 53.8 ± 9.2% at LT-FU). BDI and SF36 had improved by 40% and 23%, respectively, at LT-FU (n = 14). Stimulation-induced adverse events included swallowing difficulties, dysarthria, and bradykinesia. Pulse generator (n = 3) and electrodes (n = 5) were revised in seven patients due to infection.ConclusionsPallidal DBS is a safe and efficacious long-term treatment for dystonia with sustained effects on motor impairment and disability, accompanied by a robust improvement in mood and quality of life.

Interleaving stimulation mode can improve better the health-related quality of life in primary generalized or segmental dystonia than standard bilateral pallidal deep brain stimulation

For the treatment of drug-refractory dystonia, bilateral pallidal deep brain stimulation (GPi-DBS) is proven to be an efficient option. However, a considerable portion (10–25%) of patients experience minimal alleviation despite good electrode placement. These patients can be regarded as non-responders to GPi-DBS. In cases series, the interleaving stimulation mode (ILSM) could improve dystonia in patients not responding to standard stimulation techniques. T In this prospective, randomized, double-blind and cross-over study, 34 patients with primary generalized or segmental dystonia were enrolled. Patients underwent four visits: (1) preoperative, (2) prestimulation (4 weeks after electrode implantation BUT before turning on the stimulation), (3) 3 months and (4) 6 months stimulation. Based on electrode location, the best two contacts were activated with submaximal amplitude, 120 μs, and 130 Hz. Patients were randomly assigned to either DMSM-ILSM or ILSM-DMSM sequence. Changes in Burke-Fahn-Marsden DRS, health-related quality of life (SF-36) and side-effects were compared Thirty patients completed the study protocol. A linear mixed model analysis was used to compare the efficacy of the two stimulation modes. The dystonia severity (DRS) significantly improved from the preoperative 33 points (median) to 10 points (median) after 6 months of stimulation (p = .001). There was a trend that ILSM was more efficient (p = .094). The SF-36 improved significantly from the preoperative 49 (median) to 74 (median) after 6 months stimulation (p = .001). The ILSM was superior to the DMSM (p = .010). Although the interleaving stimulation was only tendentiously better at reducing dystonia severity, it was associated with better health-related quality of life.

Globus pallidus internus deep brain stimulation improves axial symptoms of Parkinson patients after long-term subthalamic nucleus stimulation: A case series study

IntroductionSome patients with advanced Parkinson's disease (PD) develop refractory axial symptoms and motor complications following initially effective subthalamic nucleus (STN) deep brain stimulation (DBS). We aim to determine whether globus pallidus internus (GPi) stimulation can improve refractory axial symptoms and dyskinesia, as well as psychosocial functioning and quality of life, in this group of patients who no longer benefit from STN DBS. MethodsIn this pilot study, bilateral pallidal stimulation treatment was given to 7 patients with advanced PD who had developed refractory axial symptoms, including speech and swallowing difficulties, and painful dyskinesia, after long-term (>5 y) subthalamic stimulation. The follow-up period was 6 months. Primary clinical outcome measures focused on motor symptom severity, motor complications, psychosocial function, and quality of life. Secondary outcome measures included daily dose of antiparkinsonian medication and patient's body weight. ResultsAfter pallidal stimulation, patients showed an overall 44% improvement in motor symptom scores at 6-month follow-up along with a 49% improvement in dyskinesia, a 33% improvement in psychosocial functioning, and a 42% improvement in quality of life. No adverse events occurred during the study. ConclusionsThese initial results indicate that bilateral GPi DBS could provide significant clinical benefits to patients whose axial symptoms cannot or can no longer be controlled by STN DBS.

P.012 Bilateral pallidal deep brain stimulation in a patient with chorea-acanthocytosis

Background: Chorea-acanthocytosis (ChAc) is a rare autosomal recessive neurodegenerative disease due to mutation of the VPS13A gene encoding the protein chorein. ChAc is a slowly progressive disorder that typically presents in early adulthood, and whose clinical features include chorea and dystonia with involuntary lip, cheek and tongue biting. Some patients also have seizures. Treatment for ChAc is symptomatic. A small number of ChAc patients have been treated with bilateral deep brain stimulation (DBS) of the globus pallidus interna (GPi), and we now present an additional case. Methods: Patient chart, functional measures, and laboratory findings were reviewed from the time of ChAc diagnosis until 6 months after deep brain stimulation (DBS) surgery. Results: Here we present a case of ChAc in a 31 year old male positive for VPS13A gene muations who presented with chorea, tongue biting, dysarthria, weight loss, and mild cognitive dysfunction. GPi-DBS using monopolar stimulation was associated with significant improvement in chorea and dysarthria. Conclusions: This case adds to the current state of knowledge regarding the efficacy and safety of bilateral GPi-DBS for symptomatic control of drug-resistant hyperkinetic movements seen in ChAc. Controlled trials are needed to better assess the impact of DBS in ChAc.

Amelioration of Dystonic Opisthotonus in Pantothenate Kinase-Associated Neurodegeneration Syndrome with Absent "Eye-of-the-Tiger" Sign Following Bilateral Pallidal Deep Brain Stimulation.

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Long-Term Outcomes of Bilateral Pallidal Deep Brain Stimulation for X-Linked Dystonia and Parkinsonism

Background: X-linked dystonia parkinsonism (XDP) causes adult-onset progressive dystonia and parkinsonism, which may not respond to pharmacotherapy. Objective: Previous case reports have reported beneficial effects from bilateral pallidal (GPi) deep brain stimulation (DBS). Here, we report the long-term clinical outcomes of 3 patients treated at our center. Methods: All patients presented with medication refractory dystonia and parkinsonism. They were followed prospectively. Clinical evaluations included the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and the Unified Parkinson’s Disease Rating Scale (UPDRS). Adverse events were recorded. Results: The average length of follow-up was 45.7 months. No serious adverse events occurred. All patients experienced an immediate and sustained improvement in dystonia. Mean percentage improvement in motor subscores of BFMDRS was 63.5% at the last follow-up visit. Parkinsonism was less responsive to neuromodulation, with a mean improvement in UPDRS-III of 39.5%. Standard pallidal stimulation parameters were used. Freezing of gait developed after DBS therapy in 2 patients, stimulation-induced in one and due to disease progression in the other. Conclusion: Bilateral pallidal DBS resulted in significant and sustained improvement in dystonia and moderate improvement in parkinsonism. Pallidal DBS represents an important treatment option for XPD for the management of motor symptoms.

Long-term outcomes of pallidal deep brain stimulation in X-linked dystonia parkinsonism (XDP): Up to 84 months follow-up and review of literature

IntroductionX-linked dystonia-parkinsonism (XDP/DYT3/Lubag) patients had improved dystonia and parkinsonism with bilateral pallidal deep brain stimulation (DBS) in the literature. MethodWe reviewed eleven XDP patients who underwent bilateral pallidal DBS from October 2009 to September 2018. The Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and Unified Parkinson's Disease Rating Scale (UPDRS)-III scores were reviewed from baseline up to the longest follow-up together with the demographic and clinical data. The published case reports on DBS in XDP were also reviewed. ResultsThe mean age was 39 ± 9.2 years with a mean disease duration of 3 years (range 1–9 years). An immediate response for dystonia post-DBS (1 month) was seen in all cases, with a mean BFMDRS score of 23.3 ± 12.12 [from a mean baseline of 36.3 ± 12.1] and a small change in the mean UPDRS-III score of 20 ± 10.39 [from a mean baseline of 24.04 ± 8.74]. At 12 months (n = 10), the mean BFMDRS score was 13.7 ± 10.63 and the mean UPDRS-III score was 19 ± 13.19. There was improvement in the clinical and functional stage of the patients, with majority in Stage 1 (n = 3) and Stage 2 (n = 5) at their last follow-up. ConclusionBilateral pallidal DBS should be considered as a treatment option for XDP. It is effective in the first 12 months in controlling dystonia with variable response in controlling parkinsonism. It may be effective in up to 72–84 months, as seen in three patients.

Myoclonus-dystonia: classification, phenomenology, pathogenesis, and treatment.

The present study will highlight recent advances in the field of myoclonus-dystonia with a focus on clinical aspects, pathogenesis, and treatment. We will also discuss genetics, classification issues, and diagnostic criteria. Myoclonus-dystonia is a clinical syndrome corresponding to the phenotype linked to SGCE, the main causative gene. Childhood-onset myoclonus that predominates over dystonia with prominent upper body involvement, an absence of truncal dystonia, associated anxiety or compulsivity, and a positive family history are helpful diagnostic clues. Recent studies demonstrated that zonisamide is an interesting therapeutic option in myoclonus-dystonia, and that bilateral pallidal stimulation has major and lasting therapeutic effects. Accumulating evidence suggests that an alteration in cerebello-thalamic pathway function may play a prominent role and that this is possibly related to a GABAergic deficit reflecting Purkinje cell dysfunction. Impaired striatal plasticity and disturbed serotonin homeostasis may also be implicated. Newly available cellular and rodent models may further assist in investigating the pathogenesis of this disorder. Comprehensive analysis of the phenotype and precise classification are important in patients with myoclonus and dystonia to identify homogeneous groups of patients. This is critical to guide tailored therapeutic strategies and promote effective research.

Phenotype variability and allelic heterogeneity in KMT2B-Associated disease

BackgroundMutations in Lysine-Specific Histone Methyltransferase 2B gene (KMT2B) have been reported to be associated with complex early-onset dystonia. Almost all reported KMT2B mutations occurred de novo in the paternal germline or in the early development of the patient. We describe clinico-genetic features on four Japanese patients with novel de novo mutations and demonstrate the phenotypic spectrum of KMT2B mutations. MethodsWe performed genetic studies, including trio-based whole exome sequencing (WES), in a cohort of Japanese patients with a seemingly sporadic early-onset generalized combined dystonia. Potential effects by the identified nucleotide variations were evaluated biologically. Genotype-phenotype correlations were also investigated. ResultsFour patients had de novo heterozygous mutations in KMT2B, c.309delG, c.1656dupC, c.3325_3326insC, and c.5636delG. Biological analysis of KMT2B mRNA levels showed a reduced expression of mutant transcript frame. All patients presented with motor milestone delay, microcephaly, mild psychomotor impairment, childhood-onset generalized dystonia and superimposed choreoathetosis or myoclonus. One patient cannot stand due to axial hypotonia associated with cerebellar dysfunction. Three patients had bilateral globus pallidal deep brain stimulation (DBS) with excellent or partial response. ConclusionsWe further demonstrate the allelic heterogeneity and phenotypic variations of KMT2B-associated disease. Haploinsufficiency is one of molecular pathomechanisms underlying the disease. Cardinal clinical features include combined dystonia accompanying mild psychomotor disability. Cerebellum would be affected in KMT2B-associated disease.

Excellent outcome after bilateral pallidal deep brain stimulation in generalized dystonia due to amphetamine-induced bilateral basal ganglia necrosis

Excellent outcome after bilateral pallidal deep brain stimulation in generalized dystonia due to amphetamine-induced bilateral basal ganglia necrosis

Effects of bilateral pallidal deep brain stimulation on chorea after pulmonary thromboendarterectomy with deep hypothermia and circulatory arrest: a case report

A 41-year-old man was diagnosed with chronic pulmonary thromboembolism and underwent pulmonary thromboendarterectomy (PTE) with deep hypothermia and circulatory arrest. Five days after the operation, chorea emerged in the lower extremities. The patient was referred to our hospital for disabling chorea 16years after PTE. Neurological examination revealed choreatic movements in the four extremities. Brain magnetic resonance images indicated atrophy in the bilateral head of the caudate nuclei. The patient underwent deep brain stimulation (DBS) of the bilateral globus pallidus interna (GPi). Continuous GPi-DBS diminished the choreatic movements. GPi-DBS may be a treatment option for sustained choreatic movements after PTE.

Long-term clinical outcome of bilateral pallidal stimulation for intractable craniocervical dystonia (Meige syndrome). Report of 6 patients

BackgroundThe aim of the present study was to report the short-term as well long-term results of bilateral pallidal stimulation in 6 consecutive patients for severe debilitating craniocervical dystonia (Meige syndrome) using Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). MethodsWe evaluated 6 consecutive patients with the diagnosis of intractable long-standing craniocervical dystonia. The formal objective assessment included the motor and disability BFMDRS scores. The BFMDRS assessment was performed before and after it roughly annually up to 60months when bilateral pallidal stimulation was switched on and compared to baseline BFMDRS scores. We present short-term (3months postoperatively) follow-up as well long-term (from 6 to 60months) results. Baseline BFMDRS scores and subsequent follow-up BFMDRS scores were compared with the use of a Wilcoxon signed-rank test for matched pairs. A two-tailed probability level of 5% (p<0.05) was considered significant. ResultsBilateral GPi DBS improved the BFMDRS total movement score by 65% at short-term follow-up and by 53% at long-term follow-up when compared to baseline scores. Subscores for eyes at short-term follow-up were reduced by 78%, for mouth by 58%, and for speech/swallowing by 49%. This improvements for individual subscores were maintained at long-term follow-up and were as follows for eyes by 67%, mouth by 50% and speech/swallowing by 39%. The BFMDRS disability score was reduced by 48% at short-term follow-up and by 55% at long-term follow-up when compared to baseline scores. ConclusionOur results showed that bilateral GPi DBS in craniocervical dystonia is effective and safe. Phasic dystonic movements like blepharospasm or oromandibular dystonia responded very fast and favorable to pallidal stimulation reducing disabilities.

Improvement of Post-hypoxic Myoclonus with Bilateral Pallidal Deep Brain Stimulation: A Case Report and Review of the Literature.

BackgroundPost-hypoxic myoclonus (PHM) is a syndrome that occurs when a patient has suffered hypoxic brain injury. The myoclonus is usually multifocal and generalized, often stemming from both cortical and subcortical origins. In severe cases, pharmacological treatments with antiepileptic medications may not satisfactorily control the myoclonus.MethodsWe present a case of a 23-year-old male with chronic medication refractory PHM following a cardiopulmonary arrest related to an asthmatic attack who improved with bilateral globus pallidus internus (GPi) deep brain stimulation (DBS). We review the clinical features of PHM, as well as the preoperative and postoperative Unified Myoclonus Rating Scale scores and DBS programming parameters in this patient and compare them with the three other published PHM-DBS cases in the literature.ResultsThis patient experienced an alleviation of myoclonic jerks at rest and a 39% reduction in action myoclonus with improvement in both positive and negative myoclonus with bilateral GPi-DBS. High frequency stimulation (130 Hz) with amplitudes >2.5 V were needed for the therapeutic response.DiscussionWe demonstrate a robust improvement in a medication refractory PHM patient with bilateral GPi-DBS, and suggest that it is a viable therapeutic option for debilitating post-hypoxic myoclonus.