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Child's Nervous System : ChNS :... Oct 2023Non-spastic movement disorders in children are common, although true epidemiologic data is difficult to ascertain. Children are more likely than adults to have... (Review)
Review
BACKGROUND
Non-spastic movement disorders in children are common, although true epidemiologic data is difficult to ascertain. Children are more likely than adults to have hyperkinetic movement disorders defined as tics, dystonia, chorea/athetosis, or tremor. These conditions manifest from acquired or heredodegenerative etiologies and often severely limit function despite medical and surgical management paradigms. Neurosurgical management for these conditions is highlighted.
METHODS
We performed a focused review of the literature by searching PubMed on 16 May 2023 using key terms related to our review. No temporal filter was applied, but only English articles were considered. We searched for the terms (("Pallidotomy"[Mesh]) OR "Rhizotomy"[Mesh]) OR "Deep Brain Stimulation"[Mesh], dystonia, children, adolescent, pediatric, globus pallidus, in combination. All articles were reviewed for inclusion in the final reference list.
RESULTS
Our search terms returned 37 articles from 2004 to 2023. Articles covering deep brain stimulation were the most common (n = 34) followed by pallidotomy (n = 3); there were no articles on rhizotomy.
DISCUSSION
Non-spastic movement disorders are common in children and difficult to treat. Most of these patients are referred to neurosurgery for the management of dystonia, with modern neurosurgical management including pallidotomy, rhizotomy, and deep brain stimulation. Historically, pallidotomy has been effective and may still be preferred in subpopulations presenting either in status dystonicus or with high risk for hardware complications. Superiority of DBS over pallidotomy for secondary dystonia has not been determined. Rhizotomy is an underutilized surgical tool and more study characterizing efficacy and risk profile is indicated.
Topics: Adult; Adolescent; Humans; Child; Dystonia; Movement Disorders; Tremor; Dystonic Disorders; Neurosurgical Procedures; Globus Pallidus; Deep Brain Stimulation; Treatment Outcome
PubMed: 37522933
DOI: 10.1007/s00381-023-06100-1 -
Neurologia 2022A growing body of evidence highlights the importance of understanding both the sensory and the motor pathophysiology of focal dystonia in order to improve its treatment....
INTRODUCTION
A growing body of evidence highlights the importance of understanding both the sensory and the motor pathophysiology of focal dystonia in order to improve its treatment. This study aims to evaluate somatosensory afferences in patients with focal or segmental dystonia affecting the upper limbs, to analyse whether the dominant limb is more frequently affected, to analyse pain tolerance, and to examine the potential association with pain perception in patients with hand dystonia.
METHODS
We recruited 24 participants: 12 patients with focal hand dystonia and 12 individuals without dystonia. All participants were evaluated with a digital algometer (Somedic SenseLab AB®, Farsta, Sweden), a Semmes-Weinstein monofilament test, and the visual analogue scale for pain.
RESULTS
According to our data, patients showed greater impairment in surface sensitivity than controls, both in the dominant and the non-dominant hands, as well as greater presence of pain (P > .001). Furthermore, the dystonia group showed a negative correlation between perceived pain and pressure pain tolerance threshold (rho = -0.83; P < .001).
CONCLUSIONS
Patients with focal hand dystonia presented alterations in sensitivity and more severe perceived pain than individuals without dystonia. Future studies with larger samples should aim to analyse the clinical implications and everyday impact of both objective and subjective pain.
Topics: Humans; Dystonia; Dystonic Disorders; Hand; Pain
PubMed: 34801480
DOI: 10.1016/j.nrleng.2019.12.005 -
Brain : a Journal of Neurology Jul 2023ATP5F1B is a subunit of the mitochondrial ATP synthase or complex V of the mitochondrial respiratory chain. Pathogenic variants in nuclear genes encoding assembly...
ATP5F1B is a subunit of the mitochondrial ATP synthase or complex V of the mitochondrial respiratory chain. Pathogenic variants in nuclear genes encoding assembly factors or structural subunits are associated with complex V deficiency, typically characterized by autosomal recessive inheritance and multisystem phenotypes. Movement disorders have been described in a subset of cases carrying autosomal dominant variants in structural subunits genes ATP5F1A and ATP5MC3. Here, we report the identification of two different ATP5F1B missense variants (c.1000A>C; p.Thr334Pro and c.1445T>C; p.Val482Ala) segregating with early-onset isolated dystonia in two families, both with autosomal dominant mode of inheritance and incomplete penetrance. Functional studies in mutant fibroblasts revealed no decrease of ATP5F1B protein amount but severe reduction of complex V activity and impaired mitochondrial membrane potential, suggesting a dominant-negative effect. In conclusion, our study describes a new candidate gene associated with isolated dystonia and confirms that heterozygous variants in genes encoding subunits of the mitochondrial ATP synthase may cause autosomal dominant isolated dystonia with incomplete penetrance, likely through a dominant-negative mechanism.
Topics: Humans; Dystonia; Dystonic Disorders; Mitochondrial Proton-Translocating ATPases; Mutation, Missense; Pedigree; Proteins
PubMed: 36860166
DOI: 10.1093/brain/awad068 -
Current Neuropharmacology 2023Dystonia, the third most common movement disorder, refers to a heterogeneous group of neurological diseases characterized by involuntary, sustained or intermittent... (Review)
Review
Dystonia, the third most common movement disorder, refers to a heterogeneous group of neurological diseases characterized by involuntary, sustained or intermittent muscle contractions resulting in repetitive twisting movements and abnormal postures. In the last few years, several studies on animal models helped expand our knowledge of the molecular mechanisms underlying dystonia. These findings have reinforced the notion that the synaptic alterations found mainly in the basal ganglia and cerebellum, including the abnormal neurotransmitters signalling, receptor trafficking and synaptic plasticity, are a common hallmark of different forms of dystonia. In this review, we focus on the major contribution provided by rodent models of DYT-, DYT-, DYT-, DYT/ PARK-, DYT/PARK- and DYT- dystonia, which reveal that an abnormal motor network and synaptic dysfunction represent key elements in the pathophysiology of dystonia.
Topics: Animals; Dystonia; Dystonic Disorders; Basal Ganglia; Cerebellum; Disease Models, Animal
PubMed: 37464831
DOI: 10.2174/1570159X21666230718100156 -
Experimental Brain Research Aug 2020Studying plasticity mechanisms with Professor John Rothwell was a shared highlight of our careers. In this article, we discuss non-invasive brain stimulation techniques... (Review)
Review
Studying plasticity mechanisms with Professor John Rothwell was a shared highlight of our careers. In this article, we discuss non-invasive brain stimulation techniques which aim to induce and quantify plasticity, the mechanisms and nature of their inherent variability and use such observations to review the idea that excessive and abnormal plasticity is a pathophysiological substrate of dystonia. We have tried to define the tone of our review by a couple of Professor John Rothwell's many inspiring characteristics; his endless curiosity to refine knowledge and disease models by scientific exploration and his wise yet humble readiness to revise scientific doctrines when the evidence is supportive. We conclude that high variability of response to non-invasive brain stimulation plasticity protocols significantly clouds the interpretation of historical findings in dystonia research. There is an opportunity to wipe the slate clean of assumptions and armed with an informative literature in health, re-evaluate whether excessive plasticity has a causal role in the pathophysiology of dystonia.
Topics: Dystonia; Dystonic Disorders; Humans; Neuronal Plasticity
PubMed: 32206849
DOI: 10.1007/s00221-020-05773-3 -
Neurobiology of Disease Dec 2022During the last decades deep brain stimulation (DBS) has become an important treatment option for a variety of neurological disorders such as drug-intractable dystonia.... (Review)
Review
During the last decades deep brain stimulation (DBS) has become an important treatment option for a variety of neurological disorders such as drug-intractable dystonia. Yet, the mechanisms of action of DBS are still largely unknown. Dystonia is a heterogenous movement disorder characterized by involuntary muscle contractions causing abnormal movements, postures, or both. The underlying pathophysiological processes remain unclear, but a dysfunction of the basal ganglia circuit is critically involved as supported by the effectiveness of DBS of the globus pallidus internus (GPi) in various types of dystonia. However, the degree of clinical improvement differs among the types of dystonia, as well as from patient to patient, and the delayed response to GPi-DBS in dystonia patients hampers the adjustment and optimization of stimulation parameters. Preclinical studies in suitable animal models can contribute decisively to detect the underlying mechanisms of DBS and biomarkers, to identify new possible stimulation targets and to optimize stimulation patterns. In this review, we give an overview of previous research on DBS in animal models of dystonia. With regard to the aims of research we discuss the opportunities and limitations concerning different available animal models of dystonia and technical challenges.
Topics: Animals; Dystonia; Deep Brain Stimulation; Globus Pallidus; Dystonic Disorders; Models, Animal; Treatment Outcome
PubMed: 36307031
DOI: 10.1016/j.nbd.2022.105912 -
Journal of the Neurological Sciences Apr 2022Dystonia and tremor frequently co-occur. In some cases, they have shared biological mechanisms, while in others dystonia and tremor are two comorbid conditions. The term... (Review)
Review
Dystonia and tremor frequently co-occur. In some cases, they have shared biological mechanisms, while in others dystonia and tremor are two comorbid conditions. The term "dystonic tremor" is used to describe tremor in those who have dystonia. Two mutually exclusive definitions of "dystonic tremor" were proposed. According to one definition, dystonic tremor is the tremor in the dystonic body part. An alternate definition of dystonic tremor entails irregular and jerky oscillations that have saw tooth appearance with or without overt dystonia. This paper outlines the differences in two definitions of dystonic tremor and identifies their limitations. Given the diverse views defining "dystonic tremor", this paper will use the term "tremor in dystonia". In addition, we will outline different ways to separate the subtypes of tremor in dystonia. Then we will discuss pathophysiological mechanisms derived from the objective measures and single neuron physiology analyses of tremor in dystonia. This article is part of the Special Issue "Tremor" edited by Daniel D. Truong, Mark Hallett, and Aasef Shaikh.
Topics: Dystonia; Dystonic Disorders; Essential Tremor; Humans; Tremor
PubMed: 35259651
DOI: 10.1016/j.jns.2022.120199 -
Toxins Nov 2022Oromandibular dystonia (OMD) induces severe motor impairments, such as masticatory disturbances, dysphagia, and dysarthria, resulting in a serious decline in quality of... (Review)
Review
Oromandibular dystonia (OMD) induces severe motor impairments, such as masticatory disturbances, dysphagia, and dysarthria, resulting in a serious decline in quality of life. Non-invasive brain-imaging techniques such as electroencephalography (EEG) and magnetoencephalography (MEG) are powerful approaches that can elucidate human cortical activity with high temporal resolution. Previous studies with EEG and MEG have revealed that movements in the stomatognathic system are regulated by the bilateral central cortex. Recently, in addition to the standard therapy of botulinum neurotoxin (BoNT) injection into the affected muscles, bilateral deep brain stimulation (DBS) has been applied for the treatment of OMD. However, some patients' OMD symptoms do not improve sufficiently after DBS, and they require additional BoNT therapy. In this review, we provide an overview of the unique central spatiotemporal processing mechanisms in these regions in the bilateral cortex using EEG and MEG, as they relate to the sensorimotor functions of the stomatognathic system. Increased knowledge regarding the neurophysiological underpinnings of the stomatognathic system will improve our understanding of OMD and other movement disorders, as well as aid the development of potential novel approaches such as combination treatment with BoNT injection and DBS or non-invasive cortical current stimulation therapies.
Topics: Humans; Botulinum Toxins; Dystonia; Deep Brain Stimulation; Quality of Life; Dystonic Disorders
PubMed: 36356002
DOI: 10.3390/toxins14110751 -
Movement Disorders : Official Journal... Mar 2021Stereotactic lesioning of the bilateral globus pallidus (GPi) was one of the first surgical treatments for medication-refractory dystonia but has largely been abandoned... (Review)
Review
Stereotactic lesioning of the bilateral globus pallidus (GPi) was one of the first surgical treatments for medication-refractory dystonia but has largely been abandoned in clinical practice after the introduction of deep brain stimulation (DBS). However, some patients with dystonia are not eligible for DBS. Therefore, we reviewed the efficacy, safety, and sustainability of bilateral pallidotomy by conducting a systematic review of individual patient data (IPD). Guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and IPD were followed. In May 2020, Medline, Embase, Web of Science, and Cochrane Library were searched for studies reporting on outcome of bilateral pallidotomy for dystonia. If available, IPD were collected. In this systematic review, 100 patients from 33 articles were evaluated. Adverse events were reported in 20 patients (20%), of which 8 were permanent (8%). Pre-and postoperative Burke-Fahn-Marsden Dystonia Rating Movement Scale scores were available for 53 patients. A clinically relevant improvement (>20%) of this score was found in 42 of 53 patients (79%). Twenty-five patients with status dystonicus (SD) were described. In all but 2 the SD resolved after bilateral pallidotomy. Seven patients experienced a relapse of SD. Median-reported follow-up was 12 months (n = 83; range: 2-180 months). Based on the current literature, bilateral pallidotomy is an effective and relatively safe procedure for certain types of dystonia, particularly in medication-refractory SD. Although due to publication bias the underreporting of negative outcomes is very likely, bilateral pallidotomy is a reasonable alternative to DBS in selected dystonia patients. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Topics: Deep Brain Stimulation; Dystonia; Dystonic Disorders; Globus Pallidus; Humans; Movement Disorders; Pallidotomy; Treatment Outcome
PubMed: 33215750
DOI: 10.1002/mds.28384 -
Annals of Clinical and Translational... Apr 2021Ablation of the globus pallidus internus (pallidotomy) is an effective surgical intervention for dystonia. However, the current literature on the efficacy and safety of...
OBJECTIVE
Ablation of the globus pallidus internus (pallidotomy) is an effective surgical intervention for dystonia. However, the current literature on the efficacy and safety of pallidotomy for dystonia is derived only from single-case reports and small cohort studies.
METHODS
We retrospectively analyzed patients with primary dystonia who underwent pallidotomy at our institution between 2014 and 2019. Neurological conditions were evaluated using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS, range: 0-120). We evaluated the total BFMDRS score and each subitem score (nine body regions) in the patients who underwent unilateral and bilateral pallidotomy before surgery and at last available follow-up. Moreover, postoperative complications were analyzed.
RESULTS
We found that 69 and 20 patients underwent unilateral and bilateral pallidotomy respectively. The mean age at dystonia onset was 40.4 ± 15.2 years. The mean clinical follow-up period was 17.2 ± 11.6 months. Unilateral pallidotomy significantly improved the total BFMDRS score from 11.2 ± 14.7 preoperatively to 5.4 ± 7.6 at last available follow-up (51.8% improvement, p < 0.001). Furthermore, there was a significant and independent improvement in all midline BFMDRS subitems, including eyes, mouth, speech/swallow, and neck, after unilateral pallidotomy. Bilateral pallidotomy significantly improved the total BFMDRS score from 14.6 ± 10.2 preoperatively to 3.8 ± 8.2 at last available follow-up (74.0% improvement, p < 0.001). However, bilateral pallidotomy induced medically refractory parkinsonism (postural instability and gait disturbance) in five patients, dysarthria in three patients, and dysphagia in one patient.
INTERPRETATION
Unilateral radiofrequency pallidotomy remains a viable treatment option for patients with some forms of dystonia. Bilateral pallidotomy cannot be recommended due to unacceptably high complication rates.
Topics: Adult; Age of Onset; Aged; Dystonic Disorders; Female; Follow-Up Studies; Humans; Male; Middle Aged; Outcome Assessment, Health Care; Pallidotomy; Radiofrequency Ablation; Retrospective Studies
PubMed: 33720521
DOI: 10.1002/acn3.51333