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To compare the inter-rater reliability (IRR) of five clinical rating scales for video-based assessment of hemifacial spasm (HFS) motor severity. We evaluated the video recordings of 45 HFS participants recruited through the Dystonia Coalition. In Round 1, six clinicians with expertise in HFS assessed the participants motor severity with five scales used to measure motor severity of HFS: the Jankovic rating scale (JRS), Hemifacial Spasm Grading Scale (HSGS), Samsung Medical Center (SMC) grading system for severity of HFS spasms (Lees scale), clinical grading of spasm intensity (Chens scale), and a modified version of the Abnormal Involuntary Movement Scale (Tuncs scale). In Round 2, clinicians rated the same cohort with simplified scale wording after consensus training. For each round, we evaluated the IRR using the intraclass correlation coefficient [ICC (2,1) single-rater, absolute-agreement, 2-way random model]. The scales exhibited IRR that ranged from poor to moderate; the mean ICCs were 0.41, 0.43, 0.47, 0.43, and 0.65 for the JRS, HSGS, Lees, Chens, and Tuncs scales, respectively, for Round 1. In Round 2, the corresponding IRRs increased to 0.63, 0.60, 0.59, 0.53, and 0.71. In both rounds, Tuncs scale exhibited the highest IRR. For clinical assessments of HFS motor severity based on video observations, we recommend using Tuncs scale because of its comparative reliability and because clinicians interpret the scale easily without modifications or the need for consensus training.

PurposeDominant variants in the retinoic acid receptor beta (RARB) gene underlie a syndromic form of microphthalmia, known as MCOPS12, which is associated with other birth anomalies and global developmental delay with spasticity and/or dystonia. Here, we report 25 affected individuals with 17 novel pathogenic or likely pathogenic variants in RARB. This study aims to characterize the functional impact of these variants and describe the clinical spectrum of MCOPS12.MethodsWe used in vitro transcriptional assays and in silico structural analysis to assess the functional relevance of RARB variants in affecting the normal response to retinoids.ResultsWe found that all RARB variants tested in our assays exhibited either a gain-of-function or a loss-of-function activity. Loss-of-function variants disrupted RARB function through a dominant-negative effect, possibly by disrupting ligand binding and/or coactivators' recruitment. By reviewing clinical data from 52 affected individuals, we found that disruption of RARB is associated with a more variable phenotype than initially suspected, with the absence in some individuals of cardinal features of MCOPS12, such as developmental eye anomaly or motor impairment.ConclusionOur study indicates that pathogenic variants in RARB are functionally heterogeneous and associated with extensive clinical heterogeneity.

Introduction: Oculogyric crisis (OGC) is a dystonic movement disorder of varying durations that manifests as bilateral paroxysmal upward eye deviation accompanied by involuntary blinking, tongue protrusion, and autonomic symptoms. Separately, septo-optic dysplasia (SOD) is a congenital disorder involving hypoplasia of the optic nerve as well as hypothalamic and pituitary abnormalities. In the presented case, we report a case of OGC in the setting of SOD with proposed pathogenesis. Case Presentation: A 27-year-old female presented with a history of SOD (optic nerve hypoplasia and hypopituitarism) with acute, recurrent, painless, bilateral, intermittent, simultaneous tonic conjugate upward eye deviation (i.e., OGC) and dystonic body posturing. She experienced her first episode upon meeting her biological sister for the first time at a loud, crowded public restaurant with continued episodes of OGC increasing in frequency and duration over the subsequent months. She later responded well to treatment with carbidopa/levodopa. Conclusion: Based on our current understanding of OGC, we hypothesize that acute stressful life events in the setting of prior hypothalamic-pituitary axis dysfunction secondary to SOD could lower the threshold for developing OGC. Although most cases of OGC are idiopathic, various etiologies including medications, stress, and hormonal imbalance have been postulated as possible pathogenic mechanisms. We describe a case of SOD with OGC, and based upon our review of the English language ophthalmic literature, we believe that our case is novel.

Background Meige's syndrome is a type of facial dystonia characterized by the simultaneous occurrence of blepharospasm and oromandibular dystonia. Although botulinum toxin type A (OBTA) injections are the standard treatment, evidence of their effectiveness and safety in this scenario is still lacking.

Metoclopramide and domperidone are dopamine antagonists that can cause an acute dystonic reaction. Metoclopramide is a rare but major contributor to serotonin syndrome, particularly when used with other serotonergic agents. Serotonin syndrome is a rare, potentially life-threatening adverse reaction characterized by a triad of altered mental status, autonomic dysfunction, and neuromuscular hyperactivity that typically results from exposure to serotonergic agents. Herein, we report a previously healthy 9-year-old girl who was brought to the emergency department with an alteration in the level of conscious and involuntary repetitive movements after approximately 24 hours of receiving a therapeutic dose of metoclopramide and domperidone. Physical examination showed tachycardia, hyperthermia, and a Glasgow Coma Scale score of 11, as well as mydriasis and hyperreflexia. In addition to resolving the symptoms after administering midazolam and diphenhydramine, the diagnosis of serotonin syndrome was made based on the classical symptoms and signs, which met the Hunter criteria. This case indicates the need for clinical awareness of the life-threatening syndrome and caution with medications having potential interactions with metoclopramide.

Abstract Dystonia is characterized by sustained or intermittent involuntary muscle contractions. Psychiatric symptoms are essential non‐motor features of dystonia, and higher risks of depressive and anxiety disorders have been reported. The precedence of psychiatric to motor symptoms in some patients and the dopaminergic and serotonergic system involvement in both the motor and psychiatric aspects suggest these psychiatric disorders may be intrinsic to the neurobiology of dystonia. Nevertheless, psychiatric comorbidities are often construed as secondary reactions to motor disabilities and the negative bio‐psycho‐social impacts of dystonia, leading to underdiagnosis and undertreatment. Research on antidepressant use in dystonia is scarce, especially in children and adolescents. This report presents a 17‐year‐old female with dystonia comorbid with depression with psychotic features, whose motor symptoms improved but psychiatric symptoms persisted with dopaminergic pharmacotherapy. Sertraline was finally added 5 years after the onset and successfully managed her psychotic depression without worsening motor symptoms. Early detection, prompt diagnosis, and timely holistic treatment with dopaminergic agents, antidepressants, and psychosocial interventions are critical for the mental health of dystonia patients.

Introduction: Malingering is a differential diagnosis in the field of medical disorders, especially in the field of forensic medicine. In medicine, malingering is when a person imitates a medical or psychiatric disorder with external motivations to gain financial gain or avoid social or occupational duties. In some cases, diagnosing a medical or psychological condition from malingering can be challenging and difficult. In this case report, a patient with a history of multiple hospitalization, neurodevelopmental disorders, and intellectual disability requested to receive injectable Biperiden due to aggression, irritable mood, and neck deviation, and in order to receive it, he deliberately showed neck dystonia. This report aimed to discuss on a neuropsychiatric symptom, after which the patient requested a drug injection to resolve it, in order to differentiate possible diagnoses such as drug complication, factitious disorder, and functional neurological symptom disorder. On the other hand, during the recent searches of similar texts, conflicting results and suggestions have been presented.

Background: Deficiencies in the thyroid hormone transporter monocarboxylate 8 (MCT8) due to pathogenic variants in the SLC16A2 gene (OMIM 300095) result in a complex phenotype with main endocrine and neurologic symptoms. This rare disorder, named Allan–Herndon–Dudley syndrome (AHDS) (OMIM 300523), is inherited in an X‐linked trait. One of the prominent features of AHDS is the presence of movement disorders (MD), which are complex and carry a significant burden of the disease. Cases: Patient 1: male with hypotonia since birth, developmental delay, dystonic posturing at 4 months and at 15 months, and startle reaction developed with sensory stimuli. Patient 2: male, at 2 months, shows hypotonia and developmental delay, paroxysmal episodes triggered by a stimulus with sudden blush, tonic asymmetric posture, and no epileptiform activity. At 10 months, generalized dystonic posturing. Patient 3: typical neurodevelopmental milestones until 6 months; at 24 months, dystonia, startle reaction, and upper motoneuron signs. Conclusions: We aim to describe our patients diagnosed with AHDS, focusing on MD phenomenology and strengthening the phenotype–genotype correlations for this rare condition. [ABSTRACT FROM AUTHOR]

Background: Heterozygous loss-of-function variants in CHD8 have been associated with a syndromic neurodevelopmental-disease spectrum, collectively referred to as CHD8-related neurodevelopmental disorders. Several different clinical manifestations, affecting neurodevelopmental and systemic domains, have been described, presenting with highly variable expressivity. Some expressions are well established and comprise autism spectrum disorders, psychomotor delay with cognitive impairment, postnatal overgrowth with macrocephaly, structural brain abnormalities, gastrointestinal disturbances, and behavioral and sleep-pattern problems. However, the complete phenotypic spectrum of CHD8-related disorders is still undefined. In 2021, our group described two singular female patients with CHD8-related neurodevelopmental disorder and striking dystonic manifestations, prompting the suggestion that dystonia should be considered a possible component of this condition. Case series presentation: We describe three additional unrelated female individuals, each carrying a different CHD8 frameshift variant and whose clinical presentations were primarily characterized by young-onset dystonia. Their dystonic manifestations were remarkably heterogeneous and ranged from focal, exercise-dependent, apparently isolated forms to generalized permanent phenotypes accompanied by spasticity and tremor. Neurocognitive impairment and autistic behaviors, typical of CHD8-related disorders, were virtually absent or at the mild end of the spectrum. Conclusions: This work validates our previous observation that dystonia is part of the phenotypic spectrum of CHD8-related neurodevelopmental disorders with potential female preponderance, raising new challenges and opportunities in the diagnosis and management of this condition. It also highlights the importance of in-depth neurologic phenotyping of patients carrying variants associated with neurodevelopmental disorders, as the connection between neurodevelopmental and movement disorders is proving closer than previously appreciated. [ABSTRACT FROM AUTHOR]

GTP-cyclohydrolase 1-deficient dopa-responsive dystonia (GTPCH1-deficient DRD) typically presents in childhood with dystonic posture of the lower extremities, gait impairment, and a significant response to levodopa. We performed three-dimensional gait analysis (3DGA) to quantitatively assess the gait characteristics and changes associated with levodopa treatment in patients with GTPCH1-deficient DRD. Three levodopa-treated patients with GTPCH1-deficient DRD underwent 3DGA twice, longitudinally. Changes were evaluated for cadence; gait speed; step length; gait deviation index; kinematic data of the pelvis, hip, knee, and ankle joints; and foot progression angle. Levodopa treatment increased the cadence and gait speed in one of three patients and increased the gait deviation index in two of three patients. The kinematic data for each joint exhibited different characteristics, with some improvement observed in each of the three patients. There was consistent marked improvement in the abnormal foot progression angle; one patient had excessive external rotation of one foot, another had excessive bilateral internal rotation, and the other had excessive internal rotation of one foot and excessive external rotation of the opposite foot, all of which improved. The 3DGA findings demonstrate that the gait pathology and recovery process in GTPCH1-deficient DRD vary from case to case. Changes in the foot progression angle and gait deviation index can enable the effects of treatment to be more easily evaluated. [ABSTRACT FROM AUTHOR]

Objective: To provide a comprehensive overview of rehabilitation treatment strategies for focal hand dystonia (FHD) in musicians, examining their evolution and effectiveness. Data Sources: A systematic search of five databases, PubMed, PEDro, Cochrane Library, Trip, and Google Scholar, to identify relevant articles on FHD rehabilitation. The last search was performed on 20 December 2023. Methods: Inclusion criteria were applied to 190 initially identified articles, resulting in 17 articles for review. Exclusions were made for duplicates, irrelevant titles, abstracts, and non-rehabilitation interventions. Results: Ten different rehabilitation approaches were identified over 20 years. While no definitive intervention protocol exists, a multimodal approach is commonly recommended. Conclusions: This scoping review underscores the diversity of rehabilitation strategies for FHD. It suggests the potential of multimodal approaches, emphasizing the need for further large-scale clinical efficacy studies. [ABSTRACT FROM AUTHOR]

Pathogenic heterozygous loss of function variants in CTNNB1 are associated with CTNNB1 neurodevelopmental disorder. We report the clinical phenotype of individuals with CTNNB1 neurodevelopmental disorder using both caregiver‐reported data (medical history, adaptive function, quality of life, and behavior issues) and in‐person clinical assessments (neurological, motor, and cognitive function) in 32 individuals with likely pathogenic or pathogenic CTNNB1 variants. Most individuals had truncal hypotonia, muscle weakness, hypertonia, dystonia, microcephaly, and many had a history of tethered cord. Visual problems included strabismus, hyperopia, and familial exudative vitreoretinopathy. Half of individuals walked without an assistive device. The mean Gross Motor Functional Measure‐66 score was 56.6 (SD = 14.8). Average time to complete Nine‐Hole Peg Test was slower than norms. Mean general conceptual ability composite scores from Differential Ability Scales Second Edition were very low (M = 58.3, SD = 11.3). Fifty‐five percent of individuals had low adaptive functioning based on the Vineland Adaptive Behavioral Scales. Based upon the Child Behavior Checklist total problems score, the majority (65%) of individuals had behavioral challenges. The mean overall Quality of Life Inventory‐Disability score was 81.7 (SD = 11.9). These data provide a detailed characterization of clinical features in individuals with CTNNB1 neurodevelopmental disorder. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions The MRPS36 gene encodes a recently identified component of the 2‐oxoglutarate dehydrogenase complex (OGDHC), a key enzyme of the Krebs cycle catalyzing the oxidative decarboxylation of 2‐oxoglutarate to succinyl‐CoA. Defective OGDHC activity causes a clinically variable metabolic disorder characterized by global developmental delay, severe neurological impairment, liver failure, and early‐onset lactic acidosis.We investigated the molecular cause underlying Leigh syndrome with bilateral striatal necrosis in two siblings through exome sequencing. Functional studies included measurement of the OGDHC enzymatic activity and MRPS36 mRNA levels in fibroblasts, assessment of protein stability in transfected cells, and structural analysis. A literature review was performed to define the etiological and phenotypic spectrum of OGDHC deficiency.In the two affected brothers, exome sequencing identified a homozygous nonsense variant (c.283G>T, p.Glu95*) of MRPS36. The variant did not affect transcript processing and stability, nor protein levels, but resulted in a shorter protein lacking nine residues that contribute to the structural and functional organization of the OGDHC complex. OGDHC enzymatic activity was significantly reduced.The review of previously reported cases of OGDHC deficiency supports the association of this enzymatic defect with Leigh phenotypic spectrum and early‐onset movement disorder. Slightly elevated plasma levels of glutamate and glutamine were observed in our and literature patients with OGDHC defect.Our findings point to MRPS36 as a new disease gene implicated in Leigh syndrome. The slight elevation of plasma levels of glutamate and glutamine observed in patients with OGDHC deficiency represents a candidate metabolic signature of this neurometabolic disorder. © 2024 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions The term dystonic tremor is being increasingly used in neurological publications despite uncertainties about its meaning. We provide here a historical reconstruction from its original introduction in 1984 to help distinguish dystonia from essential tremor.A comprehensive Pubmed search of MeSH terms “dystonia”, “tremor”, and “essential tremor” provided the information base for reconstructing historical usage of the term “dystonic tremor”.Over the years, this expression was enriched of additional meanings and sided by companion descriptors, such as tremor associated with dystonia. Dystonic tremor has been considered characteristically coarse, jerky, irregular, directional and asymmetrical. These characteristics, however, are not included in the most recent definitions of tremor. The relationship between tremor and dystonia is not easy to untangle, as the two phenomena are often recognized in association. Tremor and dystonia experts have developed different visions of dystonic tremor that have been variably implemented. There are currently two independent consensus definitions, which are not coincident and imply different pathophysiological interpretations.This historical reappraisal highlights that usage of the expression dystonic tremor has evolved over time to lose its original meaning. Notwithstanding inconsistencies of current definitions, its usage has steadily increased and it is time now to agree on an updated terminology. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusion 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. [ABSTRACT FROM AUTHOR]

Status dystonicus is the most severe form of dystonia with life‐threatening complications if not treated promptly. We present consensus recommendations for the initial management of acutely worsening dystonia (including pre–status dystonicus and status dystonicus), as well as refractory status dystonicus in children. This guideline provides a stepwise approach to assessment, triage, interdisciplinary treatment, and monitoring of status dystonicus. The clinical pathways aim to: (1) facilitate timely recognition/triage of worsening dystonia, (2) standardize supportive and dystonia‐directed therapies, (3) provide structure for interdisciplinary cooperation, (4) integrate advances in genomics and neuromodulation, (5) enable multicenter quality improvement and research, and (6) improve outcomes. © 2024 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

DYT1 dystonia is a debilitating neurological movement disorder, and it represents the most frequent and severe form of hereditary primary dystonia. There is currently no cure for this disease due to its unclear pathogenesis. In our previous study utilizing patientspecific motor neurons (MNs), we identified distinct cellular deficits associated with the disease, including a deformed nucleus, disrupted neurodevelopment, and compromised nucleocytoplasmic transport (NCT) functions. However, the precise molecular mechanisms underlying these cellular impairments have remained elusive. In this study, we revealed the genome-wide changes in gene expression in DYT1 MNs through transcriptomic analysis. We found that those dysregulated genes are intricately involved in neurodevelopment and various biological processes. Interestingly, we identified that the expression level of RANBP17, a RANbinding protein crucial for NCT regulation, exhibited a significant reduction in DYT1 MNs. By manipulating RANBP17 expression, we further demonstrated that RANBP17 plays an important role in facilitating the nuclear transport of both protein and transcript cargos in induced human neurons. Excitingly, the overexpression of RANBP17 emerged as a substantial mitigating factor, effectively restoring impaired NCT activity and rescuing neurodevelopmental deficits observed in DYT1 MNs. These findings shed light on the intricate molecular underpinnings of impaired NCT in DYT1 neurons and provide novel insights into the pathophysiology of DYT1 dystonia, potentially leading to the development of innovative treatment strategies. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions Tremor disorders remain as clinical diagnoses and the rate of misdiagnosis between the commonest non‐parkinsonian tremors is relatively high.To compare the clinical features of Essential Tremor without other features (pure ET), ET plus soft dystonic signs (ET + DS), and tremor combined with dystonia (TwD).We compared the clinical features of patients with pure ET, ET + DS, and TwD enrolled in The ITAlian tremor Network (TITAN). Linear regression models were performed to determine factors associated with health status and quality of life.Three‐hundred‐eighty‐three patients were included. Sex distribution was significantly different between the groups with males being more represented in pure ET and females in TwD. The initial site of tremor was different between the groups with about 40% of TwD having head tremor and ET + DS unilateral upper limb tremor at onset. This pattern mirrored the distribution of overt dystonia and soft dystonic signs at examination. Sensory trick, task‐specificity, and position‐dependence were more common, but not exclusive, to TwD. Pure ET patients showed the lowest degree of alcohol responsiveness and ET + DS the highest. Midline tremor was more commonly encountered and more severe in TwD than in the other groups. Regression analyses demonstrated that tremor severity, sex, age, and to a lesser degree the variable “group”, independently predicted health status and quality of life, suggesting the existence of other determinants beyond tremor.Pure ET and TwD manifest with a phenotypic overlap, which calls for the identification of diagnostic biomarkers. ET + DS shared features with both syndromes, suggesting intra‐group heterogeneity. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions Motor complications are well recognized in Parkinson's disease (PD), but their reported prevalence varies and functional impact has not been well studied.To quantify the presence, severity, impact and associated factors for motor complications in PD.Analysis of three large prospective cohort studies of recent‐onset PD patients followed for up to 12 years. The MDS‐UPDRS part 4 assessed motor complications and multivariable logistic regression tested for associations. Genetic risk score (GRS) for Parkinson's was calculated from 79 single nucleotide polymorphisms.3343 cases were included (64.7% male). Off periods affected 35.0% (95% CI 33.0, 37.0) at 4–6 years and 59.0% (55.6, 62.3) at 8–10 years. Dyskinesia affected 18.5% (95% CI 16.9, 20.2) at 4–6 years and 42.1% (38.7, 45.5) at 8–10 years. Dystonia affected 13.4% (12.1, 14.9) at 4–6 years and 22.8% (20.1, 25.9) at 8–10 years. Off periods consistently caused greater functional impact than dyskinesia. Motor complications were more common among those with higher drug doses, younger age at diagnosis, female gender, and greater dopaminergic responsiveness (in challenge tests), with associations emerging 2–4 years post‐diagnosis. Higher Parkinson's GRS was associated with early dyskinesia (0.026 ≤ P ≤ 0.050 from 2 to 6 years).Off periods are more common and cause greater functional impairment than dyskinesia. We confirm previously reported associations between motor complications with several demographic and medication factors. Greater dopaminergic responsiveness and a higher genetic risk score are two novel and significant independent risk factors for the development of motor complications. [ABSTRACT FROM AUTHOR]

The acyl-CoA-binding domain-containing protein 6 (ACBD6) is ubiquitously expressed, plays a role in the acylation of lipids and proteins and regulates the N -myristoylation of proteins via N -myristoyltransferase enzymes (NMTs). However, its precise function in cells is still unclear, as is the consequence of ACBD6 defects on human pathophysiology. Using exome sequencing and extensive international data sharing efforts, we identified 45 affected individuals from 28 unrelated families (consanguinity 93%) with bi-allelic pathogenic, predominantly loss-of-function (18/20) variants in ACBD6. We generated zebrafish and Xenopus tropicalis acbd6 knockouts by CRISPR/Cas9 and characterized the role of ACBD6 on protein N -myristoylation with myristic acid alkyne (YnMyr) chemical proteomics in the model organisms and human cells, with the latter also being subjected further to ACBD6 peroxisomal localization studies. The affected individuals (23 males and 22 females), aged 1–50 years, typically present with a complex and progressive disease involving moderate-to-severe global developmental delay/intellectual disability (100%) with significant expressive language impairment (98%), movement disorders (97%), facial dysmorphism (95%) and mild cerebellar ataxia (85%) associated with gait impairment (94%), limb spasticity/hypertonia (76%), oculomotor (71%) and behavioural abnormalities (65%), overweight (59%), microcephaly (39%) and epilepsy (33%). The most conspicuous and common movement disorder was dystonia (94%), frequently leading to early-onset progressive postural deformities (97%), limb dystonia (55%) and cervical dystonia (31%). A jerky tremor in the upper limbs (63%), a mild head tremor (59%), parkinsonism/hypokinesia developing with advancing age (32%) and simple motor and vocal tics were among other frequent movement disorders. Midline brain malformations including corpus callosum abnormalities (70%), hypoplasia/agenesis of the anterior commissure (66%), short midbrain and small inferior cerebellar vermis (38% each) as well as hypertrophy of the clava (24%) were common neuroimaging findings. Acbd6 -deficient zebrafish and Xenopus models effectively recapitulated many clinical phenotypes reported in patients including movement disorders, progressive neuromotor impairment, seizures, microcephaly, craniofacial dysmorphism and midbrain defects accompanied by developmental delay with increased mortality over time. Unlike ACBD5, ACBD6 did not show a peroxisomal localization and ACBD6-deficiency was not associated with altered peroxisomal parameters in patient fibroblasts. Significant differences in YnMyr-labelling were observed for 68 co- and 18 post-translationally N -myristoylated proteins in patient-derived fibroblasts. N -myristoylation was similarly affected in acbd6 -deficient zebrafish and X. tropicalis models, including Fus, Marcks and Chchd-related proteins implicated in neurological diseases. The present study provides evidence that bi-allelic pathogenic variants in ACBD6 lead to a distinct neurodevelopmental syndrome accompanied by complex and progressive cognitive and movement disorders. [ABSTRACT FROM AUTHOR]

A neurological condition called dystonia results in abnormal, uncontrollable postures or movements because of sporadic or continuous muscular spasms. Several varieties of dystonia can impact people of all ages, leading to severe impairment and a decreased standard of living. The discovery of genes causing variations of single or mixed dystonia has improved our understanding of the disease's etiology. Genetic dystonias are linked to several genes, including pathogenic variations of VPS16, TOR1A, THAP1, GNAL, and ANO3. Diagnosis of dystonia is primarily based on clinical symptoms, which can be challenging due to overlapping symptoms with other neurological conditions, such as Parkinson's disease. This review aims to summarize recent advances in the genetic origins and management of focal dystonia. [ABSTRACT FROM AUTHOR]

Background: This exploratory study evaluated the presence of sensitization-associated and neuropathic-like symptoms and identified their association with pressure sensitivity, pain, and disability in patients with cervical dystonia (CD). Methods: Thirty-one patients with CD (74.2% women, age: 61.2 years, SD 10.1) participated. Data collected included clinical variables, the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), the Central Sensitization Inventory (CSI), the Self-administered Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), the Hospital Anxiety and Depression Scale (HADS) and the Pittsburgh Sleep Quality Index (PSQI), as well as widespread pressure pain thresholds (PPTs). Results: Patients with CD with pain (n = 20, 64.5%) showed higher scores on the TWSTRS disability subscale and the CSI (p < 0.001), and lower PPTs (p < 0.05). Fifteen patients (15/31, 48%) showed sensitization-associated symptoms (CSI ≥ 40), whereas five of the patients with pain (5/20, 25%) exhibited neuropathic-like symptoms (S-LANSS ≥ 12). The CSI and S-LANSS were positively associated with the TWSTRS, HADS-A and HADS-D, and negatively associated with PPTs. HADS-D and S-LANSS explained 72.5% of the variance of the CSI (r2: 0.725), whereas CSI explained 42.3% of the variance of the S-LANSS (r2: 0.423). Conclusions: Pain is an important source of disability in CD, and may be a consequence of different mechanisms, including sensitization. [ABSTRACT FROM AUTHOR]

The integrated stress response (ISR) is a highly conserved biochemical pathway involved in maintaining proteostasis and cell health in the face of diverse stressors. In this Review, we discuss a relatively noncanonical role for the ISR in neuromodulatory neurons and its implications for synaptic plasticity, learning, and memory. Beyond its roles in stress response, the ISR has been extensively studied in the brain, where it potently influences learning and memory, and in the process of synaptic plasticity, which is a substrate for adaptive behavior. Recent findings demonstrate that some neuromodulatory neuron types engage the ISR in an "always-on" mode, rather than the more canonical "on-demand" response to transient perturbations. Atypical demand for the ISR in neuromodulatory neurons introduces an additional mechanism to consider when investigating ISR effects on synaptic plasticity, learning, and memory. This basic science discovery emerged from a consideration of how the ISR might be contributing to human disease. To highlight how, in scientific discovery, the route from starting point to outcomes can often be circuitous and full of surprise, we begin by describing our group's initial introduction to the ISR, which arose from a desire to understand causes for a rare movement disorder, dystonia. Ultimately, the unexpected connection led to a deeper understanding of its fundamental role in the biology of neuromodulatory neurons, learning, and memory. [ABSTRACT FROM AUTHOR]

DYT1 dystonia is associated with decreased striatal dopamine release. In this study, we examined the possibility that ultrastructural changes of nigrostriatal dopamine terminals could contribute to this neurochemical imbalance using a serial block face/scanning electron microscope (SBF/SEM) and three‐dimensional reconstruction to analyse striatal tyrosine hydroxylase‐immunoreactive (TH‐IR) terminals and their synapses in a DYT1(ΔE) knockin (DYT1‐KI) mouse model of DYT1 dystonia. Furthermore, to study possible changes in vesicle packaging capacity of dopamine, we used transmission electron microscopy to assess the synaptic vesicle size in striatal dopamine terminals. Quantitative comparative analysis of 80 fully reconstructed TH‐IR terminals in the WT and DYT1‐KI mice indicate (1) no significant difference in the volume of TH‐IR terminals; (2) no major change in the proportion of axo‐spinous versus axo‐dendritic synapses; (3) no significant change in the post‐synaptic density (PSD) area of axo‐dendritic synapses, while the PSDs of axo‐spinous synapses were significantly smaller in DYT1‐KI mice; (4) no significant change in the contact area between TH‐IR terminals and dendritic shafts or spines, while the ratio of PSD area/contact area decreased significantly for both axo‐dendritic and axo‐spinous synapses in DYT1‐KI mice; (5) no significant difference in the mitochondria volume; and (6) no significant difference in the synaptic vesicle area between the two groups. Altogether, these findings suggest that abnormal morphometric changes of nigrostriatal dopamine terminals and their post‐synaptic targets are unlikely to be a major source of reduced striatal dopamine release in DYT1 dystonia. [ABSTRACT FROM AUTHOR]

Background: Cognitive dysfunction has been reported in idiopathic adult‐onset dystonia (IAOD), but whether this is a primary or secondary component of the disorder remains uncertain. Objective: Here, we aimed to analyze the key domains of abnormal cognitive performance in IAOD and whether this is associated with motor or mood changes. Methods: Article selection for our critical review was guided by PRISMA guidelines (mesh terms "dystonia" and "cognitive," publication period: 2000–2022). Only peer‐reviewed, English‐language original case–control studies involving patients with IAOD who were not exposed to dopamine‐ or acetylcholine‐modulating agents and validated cognitive assessments were included. Results: Abstract screening ultimately yielded 22 articles for full‐text review and data extraction. A greater proportion of studies (17 of 22, 82%) reported abnormal cognitive performance in IAOD. Most of these studies focused on blepharospasm (BSP) and cervical dystonia (10 and 14, respectively). Most studies reporting cognitive impairment (11 of 17) identified multidomain impairment in cognition. Executive functions were the domain most frequently explored (14 of 22 studies), 79% of which detected worse performance in people with dystonia. Results related to other domains were inconclusive. Cognitive abnormalities were independent of motor symptoms in most studies (7 of 12) that explored this relationship and independent of mood status in all 8 that investigated this. Conclusions: Within IAOD, cognitive dysfunction (in particular, executive dysfunction) has been documented mainly in BSP and cervical dystonia. More comprehensive testing is warranted to assess abnormalities in other domains and in other forms of IAOD, as well as to evaluate longitudinal progression of cognitive disturbances in this condition. [ABSTRACT FROM AUTHOR]

Background: Most of DYT genotypes follow an autosomal dominant inheritance pattern with reduced penetrance; the mechanisms underlying the disease development remain unclear. The objective of the study was to investigate cortical thickness, grey matter (GM) volumes and white matter (WM) alterations in asymptomatic (DYT-A) and symptomatic dystonia (DYT-S) mutation carriers. Methods: Eight DYT-A (four DYT-TOR1A and four DYT-THAP1), 14 DYT-S (seven DYT-TOR1A, and seven DYT-THAP1), and 37 matched healthy controls underwent 3D T1-weighted and diffusion tensor (DT) MRI to study cortical thickness, cerebellar and basal ganglia GM volumes and WM microstructural changes. Results: DYT-S showed thinning of the frontal and motor cortical regions related to sensorimotor and cognitive processing, together with putaminal atrophy and subcortical microstructural WM damage of both motor and extra-motor tracts such as cerebral peduncle, corona radiata, internal and external capsule, temporal and orbitofrontal WM, and corpus callosum. DYT-A had cortical thickening of middle frontal areas and WM damage of the corona radiata. Conclusions: DYT genes phenotypic expression is associated with alterations of both motor and extra-motor WM and GM regions. Asymptomatic genetic status is characterized by a very subtle affection of the WM motor pathway, together with an increased cortical thickness of higher-order frontal regions that might interfere with phenotypic presentation and disease manifestation. [ABSTRACT FROM AUTHOR]

• The blink reflex (BR) is a powerful electrodiagnostic tool, including but also reaching beyond disorders involving the trigemino-facial system. • Alterations in BR excitability are present in dysfunctions of many supranuclear circuits. • BR excitability modulation aids in further understanding the physiology and pathophysiology of movement control and chronic pain. The blink reflex (BR) is integrated at the brainstem; however, it is modulated by inputs from various structures such as the striatum, globus pallidus, substantia nigra, and nucleus raphe magnus but also from afferent input from the peripheral nervous system. Therefore, it provides information about the pathophysiology of numerous peripheral and central nervous system disorders. The BR is a valuable tool for studying the integrity of the trigemino-facial system, the relevant brainstem nuclei, and circuits. At the same time, some neurophysiological techniques applying the BR may indicate abnormalities involving structures rostral to the brainstem that modulate or control the BR circuits. This is a state-of-the-art review of the clinical application of BR modulation; physiology is reviewed in part 1. In this review, we aim to present the role of the BR and techniques related to its modulation in understanding pathophysiological mechanisms of motor control and pain disorders, in which these techniques are diagnostically helpful. Furthermore, some BR techniques may have a predictive value or serve as a basis for follow-up evaluation. BR testing may benefit in the diagnosis of hemifacial spasm, dystonia, functional movement disorders, migraine, orofacial pain, and psychiatric disorders. Although the abnormalities in the integrity of the BR pathway itself may provide information about trigeminal or facial nerve disorders, alterations in BR excitability are found in several disease conditions. BR excitability studies are suitable for understanding the common pathophysiological mechanisms behind various clinical entities, elucidating alterations in top-down inhibitory systems, and allowing for follow-up and quantitation of many neurological syndromes. [ABSTRACT FROM AUTHOR]

Introduction: Dystonia is a movement disorder characterized by sustained or intermittent muscle contractions. Cervical dystonia (CD) is the most common focal dystonia. There are several instruments assessing the symptoms of CD. However, different scales assess different features which may lead to poor patient evaluation. Aim: The aim of the study was to evaluate the degree of overlap of most often used CD rating scales identified by the literature review. Methods: A thorough search of the Medline database was conducted in September 2021. Then the frequency of each scale was calculated, and 7 most common scales were included in the content overlap analysis using Jaccard index (0 – no overlap, 1 – full overlap). Results: Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), Tsui score, Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS), Cervical Dystonia Impact Profile 58 (CDIP-58), Craniocervical Dystonia Questionnaire 24 (CDQ-24), Cervical Dystonia Severity Rating Scale (CDSS), Cervical Dystonia Severity Rating Scale (DDS) and The Dystonia Non-Motor Symptoms Questionnaire (DNMSQuest) were the most common scales. 91 CD symptoms were distinguished from 134 items used in the scales. The mean overlap among all scales was 0.17. 52 (62%) symptoms were examined by more than one scale. The CIDP-58 captured the highest number of symptoms (63.0%), while the CDSS captured the lowest number (8.0%). None of the symptoms were examined by seven instruments. Conclusions: There was a very weak overlap among scales. High inconsistency between the scales may lead to highly different dystonia severity assessment in clinical practice. Thus, the instruments should be combined. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusions Although the group of paroxysmal kinesigenic dyskinesia (PKD) genes is expanding, the molecular cause remains elusive in more than 50% of cases.The aim is to identify the missing genetic causes of PKD.Phenotypic characterization, whole exome sequencing and association test were performed among 53 PKD cases.We identified four causative variants in KCNJ10, already associated with EAST syndrome (epilepsy, cerebellar ataxia, sensorineural hearing impairment and renal tubulopathy). Homozygous p.(Ile209Thr) variant was found in two brothers from a single autosomal recessive PKD family, whereas heterozygous p.(Cys294Tyr) and p.(Thr178Ile) variants were found in six patients from two autosomal dominant PKD families. Heterozygous p.(Arg180His) variant was identified in one additional sporadic PKD case. Compared to the Genome Aggregation Database v2.1.1, our PKD cohort was significantly enriched in both rare heterozygous (odds ratio, 21.6; P = 9.7 × 10−8) and rare homozygous (odds ratio, 2047; P = 1.65 × 10−6) missense variants in KCNJ10.We demonstrated that both rare monoallelic and biallelic missense variants in KCNJ10 are associated with PKD. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) of the internal globus pallidus (GPi) is a recognized treatment for medication‐refractory dystonia. Problems in executive functions and social cognition can be part of dystonia phenotypes. The impact of pallidal DBS on cognition appears limited, but not all cognitive domains have been investigated yet. In the present study, we compare cognition before and after GPi DBS. Seventeen patients with dystonia of various aetiology completed pre‐ and post‐DBS assessment (mean age 51 years; range 20–70 years). Neuropsychological assessment covered intelligence, verbal memory, attention and processing speed, executive functioning, social cognition, language and a depression questionnaire. Pre‐DBS scores were compared with a healthy control group matched for age, gender and education, or with normative data. Patients were of average intelligence but performed significantly poorer than healthy peers on tests for planning and for information processing speed. Otherwise, they were cognitively unimpaired, including social cognition. DBS did not change the baseline neuropsychological scores. We confirmed previous reports of executive dysfunctions in adult dystonia patients with no significant influence of DBS on cognitive functioning in these patients. Pre‐DBS neuropsychological assessments appear useful as they support clinicians in counselling their patients. Decisions about post‐DBS neuropsychological evaluations should be made on a case‐by‐case basis. [ABSTRACT FROM AUTHOR]

Abductor laryngeal dystonia (ABLD) is a rare neurological voice disorder which results in sporadic opening of the vocal folds during speech. Etiology is unknown, and to date there is no identified effective behavioral treatment for it. It is hypothesized that LSVT LOUD®, which was developed to treat dysphonia secondary to Parkinson's disease, may have application to speakers with ABLD to improve outcomes beyond that with botulinum neurotoxin (BoNT) treatment alone. The participant received one injection of BoNT in each vocal fold 2 to 3 months prior to initiating intensive voice therapy via teletherapy. Objective measures of vocal loudness (dB sound pressure level), maximum phonation time, and high/low pitch frequency (Hz) were recorded in all treatment sessions and follow-up sessions. Over the course of treatment, the participant showed steady gains in phonation time, volume, pitch range, and vocal quality with a substantial reduction in aphonic voice breaks by the end of the treatment program. Perceptual symptoms of ABLD were nearly undetectable by the participant and the clinicians up to 12 months posttreatment, with no additional BoNT injections. The results suggest that LSVT LOUD® following BoNT was effective, with long-lasting improvement in vocal function, for this speaker with ABLD. [ABSTRACT FROM AUTHOR]

Moyamoya disease (MMD) is a progressive cerebrovascular disorder caused by narrowing of the arteries located at the base of the brain in the basal ganglia. Dystonia is a relatively rare symptom of MMD, and little is known about the treatment of this symptom in MMD patients. We report a case of dystonia in an MMD patient that was alleviated after valproate treatment. A 57-year-old female patient with MMD presented with new-onset dystonia of the left upper extremity and left hemifacial spasm. Although she already suffered from mild cognitive dysfunction, there was no exacerbation when dystonia presented. She was treated with valproate 300 mg b.i.d, and the symptoms were alleviated. We discuss the efficacy of valproate in terms of anatomy and neurotransmitters. In addition, the patient's symptoms are similar to those associated with LGI-1 encephalitis but are distinguished by the progression of the disease. [ABSTRACT FROM AUTHOR]

This report describes a 15-year-old female with known spastic and dystonic quadriplegic cerebral palsy (CP), Gross Motor Function Classification System IV, and obstructive sleep apnea (OSA). She experienced decreased apneic episodes after receiving onabotulinumtoxin A (BoNT-A) injections for the treatment of oromandibular dystonia (OMD). After her OSA diagnosis, she initially received injections to the bilateral masseter and temporalis muscles with no effect on the frequency of nightly apneic episodes. Subsequently, the bilateral lateral pterygoid muscles were added and she was later noted to have fewer apneic episodes overnight. This case report describes the use of BoNT-A in the muscles of mastication for management of OMD and the ensuing improvement in OSA in a teenager with CP. [ABSTRACT FROM AUTHOR]

Background: Pathogenic variants in several genes have been linked to genetic forms of isolated or combined dystonia. The phenotypic and genetic spectrum and the frequency of pathogenic variants in these genes have not yet been fully elucidated, neither in patients with dystonia nor with other, sometimes co‐occurring movement disorders such as Parkinson's disease (PD). Objectives: To screen >2000 patients with dystonia or PD for rare variants in known dystonia‐causing genes. Methods: We screened 1207 dystonia patients from Germany (DysTract consortium), Spain, and South Korea, and 1036 PD patients from Germany for pathogenic variants using a next‐generation sequencing gene panel. The impact on DNA methylation of KMT2B variants was evaluated by analyzing the gene's characteristic episignature. Results: We identified 171 carriers (109 with dystonia [9.0%]; 62 with PD [6.0%]) of 131 rare variants (minor allele frequency <0.005). A total of 52 patients (48 dystonia [4.0%]; four PD [0.4%, all with GCH1 variants]) carried 33 different (likely) pathogenic variants, of which 17 were not previously reported. Pathogenic biallelic variants in PRKRA were not found. Episignature analysis of 48 KMT2B variants revealed that only two of these should be considered (likely) pathogenic. Conclusion: This study confirms pathogenic variants in GCH1, GNAL, KMT2B, SGCE, THAP1, and TOR1A as relevant causes in dystonia and expands the mutational spectrum. Of note, likely pathogenic variants only in GCH1 were also found among PD patients. For DYT‐KMT2B, the recently described episignature served as a reliable readout to determine the functional effect of newly identified variants. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Objective: Dystonias, characterized by excessive muscle contractions resulting in involuntary postures and movements, impact 3 million people globally, making them the third most common movement disorder. Often accompanied by tremors, dystonias have epidemiological links and non-motor features shared with isolated tremor, such as essential tremor. Both dystonia and tremor present with balance dysfunction and abnormal involuntary movements, potentially linked to abnormal cerebellar function. This study explores the perception of one's own linear movement, heading, particularly discrimination of heading direction, in isolated cervical dystonia, isolated tremor, and their combination. We compare such perception behavior in visual and vestibular domains, predicting that visual heading perception would be superior to vestibular heading perception. Methods: Following the focus on the perception of heading direction, we used psychophysics techniques, such as two-alternative-forced-choice task, to examine perception of direction of one's own movements as they see isolated visual star-cloud movement (visual heading perception) and en bloc body movement (vestibular heading perception). We fitted a sigmoidal psychometric function curve to determine the threshold for visual or vestibular heading perception in our participants. Results: Nineteen participants underwent a two-alternative forced-choice task in the vestibular and visual domains. Results reveal elevated vestibular heading perception thresholds in cervical dystonia with or without tremor, and isolated tremor compared to healthy controls. Vestibular heading perception threshold was comparable in cervical dystonia with tremor and isolated tremor, but it was even worse in isolated cervical dystonia. Visual heading perception, however, remained less affected all three conditions—isolated cervical dystonia, isolated tremor, and their combination. Conclusion: These findings indicate shared deficits and distinctions in the perception of linear translational heading across movement disorders, such as isolated cervical dystonia, tremor, or their combination, offering insights into their pathophysiology, particularly the involvement of cerebellum regions responsible for vestibular processing. [ABSTRACT FROM AUTHOR]

Introduction: Os odontoideum refers to a rounded ossicle detached from a hypoplastic odontoid process at the body of the axis. The aetiology has been debated and believed to be either congenital or acquired (resulting from trauma). Os odontoideum results in incompetence of the transverse ligament and thus predisposes to atlantoaxial instability and spinal cord injury. Methods/results: Three cases of children with severe dystonic cerebral palsy presenting with myelopathic deterioration secondary to atlantoaxial instability due to os odontoideum are presented. This observation supports the hypothesis of os odontoideum being an acquired phenomenon, secondary to chronic excessive movement with damage to the developing odontoid process. Conclusion: In children with cerebral palsy and dystonia, pre-existing motor deficits may conceal an evolving myelopathy and result in delayed diagnosis of clinically significant atlantoaxial subluxation. [ABSTRACT FROM AUTHOR]

Dystonia is characterized by sustained or intermittent involuntary muscle contractions. Psychiatric symptoms are essential non‐motor features of dystonia, and higher risks of depressive and anxiety disorders have been reported. The precedence of psychiatric to motor symptoms in some patients and the dopaminergic and serotonergic system involvement in both the motor and psychiatric aspects suggest these psychiatric disorders may be intrinsic to the neurobiology of dystonia. Nevertheless, psychiatric comorbidities are often construed as secondary reactions to motor disabilities and the negative bio‐psycho‐social impacts of dystonia, leading to underdiagnosis and undertreatment. Research on antidepressant use in dystonia is scarce, especially in children and adolescents. This report presents a 17‐year‐old female with dystonia comorbid with depression with psychotic features, whose motor symptoms improved but psychiatric symptoms persisted with dopaminergic pharmacotherapy. Sertraline was finally added 5 years after the onset and successfully managed her psychotic depression without worsening motor symptoms. Early detection, prompt diagnosis, and timely holistic treatment with dopaminergic agents, antidepressants, and psychosocial interventions are critical for the mental health of dystonia patients. [ABSTRACT FROM AUTHOR]

Background: Mutations in ANO3 are a rare cause of autosomal dominant isolated or combined dystonia, mainly presenting in adulthood. Cases: We extensively characterize a new, large ANO3 family with six affected carriers. The proband is a young girl who had suffered from tremor and painful dystonic movements in her right arm since the age of 11 years. She later developed a diffuse dystonic tremor and mild extrapyramidal signs (ie, rigidity and hypodiadochokinesis) in her right arm. She also suffered from psychomotor delay and learning difficulties. Repeated structural and functional neuroimaging were unremarkable. A dystonic tremor was also present in her two sisters. Her paternal aunt, father, and a third older sister presented episodic postural tremor in the arms. The father and one sister also presented learning difficulties. The heterozygous p.G6V variant in ANO3 was identified in all affected subjects. Literature review: Stratification by age at onset divided ANO3 cases into two major groups, where younger patients displayed a more severe phenotype, probably due to variants near the scrambling domain. Conclusions: We describe the phenotype of a new ANO3 family and highlight the need for functional studies to explore the impact of ANO3 variants on its phospholipid scrambling activity. [ABSTRACT FROM AUTHOR]

Growing evidence points to a spectrum of non-motor symptoms, including cognitive difficulties that have a greater impact on functional outcomes and quality of life than motor symptoms in cervical dystonia (CD). Some cognitive impairments have been reported; however, findings are inconsistent, and described across mixed groups of dystonia. The current review aimed to examine the evidence for cognitive impairments in CD. MEDLINE, EMBASE, PsychINFO and Web of Science databases were searched. Studies were included if they met the following criteria (i) cross-sectional or longitudinal studies of adults with CD, (ii) where the results of standardised measures of cognitive or neuropsychological function in any form were assessed and reported, (iii) results compared to a control group or normative data, and (iv) were published in English. Results are presented in a narrative synthesis. Twenty studies were included. Subtle difficulties with general intellectual functioning, processing speed, verbal memory, visual memory, visuospatial function, executive function, and social cognition were identified while language, and attention and working memory appear to be relatively spared. Several methodological limitations were identified that should be considered when interpreting the evidence to describe a specific profile of cognitive impairment in CD. Clinical and research implications are discussed. [ABSTRACT FROM AUTHOR]

• We used simultaneous EEG and fNIRS to examine task-specific changes during finger-tapping and handwriting tasks in dystonia. • Patients with dystonia show altered connectivity between the supplementary motor area and left sensorimotor cortex during writing. • Differences in cortical blood flow and EEG spectral power between controls and patients with dystonia are task dependent. The aim of this study was to explore differences in brain activity and connectivity using simultaneous electroencephalography and near-infrared spectroscopy in patients with focal dystonia during handwriting and finger-tapping tasks. Patients with idiopathic right upper limb focal dystonia and controls were assessed by simultaneous near-infrared spectroscopy and electroencephalography during the writing and finger-tapping tasks in terms of the mu-alpha, mu-beta, beta and low gamma power and effective connectivity, as well as relative changes in oxyhemoglobin (oxy-Hb) and deoxyhemoglobin using a channel-wise approach with a mixed-effect model. Patients exhibited higher oxy-Hb levels in the right and left motor cortex and supplementary motor area during writing, but lower oxy-Hb levels in the left sensorimotor and bilateral somatosensory area during finger-tapping compared to controls. During writing, patients showed increased low gamma power in the bilateral sensorimotor cortex and less mu-beta and beta attenuation compared to controls. Additionally, patients had reduced connectivity between the supplementary motor area and the left sensorimotor cortex during writing. No differences were observed in terms of effective connectivity in either task. Finally, patients failed to attenuate the mu-alpha, mu-beta, and beta rhythms during the finger-tapping task. Cortical blood flow and EEG spectral power differ between controls and dystonia patients, depending on the task. Writing increased blood flow and altered connectivity in dystonia patients, and it also decreased slow-band attenuation. Finger-tapping decreased blood flow and slow-band attenuation. Simultaneous fNIRS and EEG may show relevant information regarding brain dynamics in movement disorders patients in unconstrained environments. [ABSTRACT FROM AUTHOR]

Background: Dystonia is a hyperkinetic movement disorder with key motor network dysfunction implicated in pathophysiology. The UK Biobank encompasses > 500,000 participants, of whom 42,565 underwent brain MRI scanning. This study applied an optimized pre-processing pipeline, aimed at better accounting for artifact and improving data reliability, to assess for grey and white matter structural MRI changes between individuals diagnosed with primary dystonia and an unaffected control cohort. Methods: Individuals with dystonia (n = 76) were identified from the UK Biobank using published algorithms, alongside an age- and sex-matched unaffected control cohort (n = 311). Grey matter morphometric and diffusion measures were assessed, together with white matter diffusion tensor and diffusion kurtosis metrics using tractography and tractometry. Post-hoc Neurite Orientation and Density Distribution Imaging (NODDI) was also undertaken for tracts in which significant differences were observed. Results: Grey matter tremor-specific striatal differences were observed, with higher radial kurtosis. Tractography identified no white matter differences, however segmental tractometry identified localised differences, particularly in the superior cerebellar peduncles and anterior thalamic radiations, including higher fractional anisotropy and lower orientation distribution index in dystonia, compared to controls. Additional tremor-specific changes included lower neurite density index in the anterior thalamic radiations. Conclusions: Analysis of imaging data from one of the largest dystonia cohorts to date demonstrates microstructural differences in cerebellar and thalamic white matter connections, with architectural differences such as less orientation dispersion potentially being a component of the morphological structural changes implicated in dystonia. Distinct tremor-related imaging features are also implicated in both grey and white matter. [ABSTRACT FROM AUTHOR]

Dystonia represents a significant source of disability in children. Generalized dystonia, which involves multiple body regions, leads to impaired mobility and motor function, resulting in substantial challenges in daily activities. Surgical treatments are used when medical treatments fail. Intrathecal baclofen (ITB) or deep brain stimulations (DBS) are the most employed surgical therapies. When these options are not feasible or ineffective, some authors have explored the use of intraventricular baclofen (IVB). In this report, we present four cases of pediatric patients with generalized dystonia who underwent treatment with IVB, resulting in notable improvements. To further explore the potential of this treatment modality, we conducted a comprehensive literature review. The findings from our study provide a comprehensive overview that can guide palliative management in similar cases. [ABSTRACT FROM AUTHOR]

Purpose: Pediatric dystonia (PD) has a significant negative impact on the growth and development of the child. This study was done retrospectively to analyze functional outcomes in pediatric patients with dystonia who underwent deep brain stimulation. Methods: In this retrospective analytical study, all the patients of age less than 18 years undergoing deep brain stimulation (DBS) for dystonia between 2012 and 2020 in a single center were analyzed and their functional outcomes were measured by the Burke–Fahn–Marsden-dystonia-rating-scale (BFMDRS). Results: A total of 10 pediatric patients were included with a mean age of onset, duration of disease, and age at surgery being 5.75 years, 7.36 years, and 13.11 years, respectively, with a mean follow-up of 23.22 months. The mean pre-DBS motor score was 75.44 ± 23.53 which improved significantly at 6-month and 12-month follow-up to 57.27 (p value 0.004) and 50.38 (p value < 0.001), respectively. Limbs sub-scores improved significantly at both the scheduled intervals. There was a significant improvement in disability at 1-year follow-up with significant improvement in feeding, dressing, and walking components. There was a 27.34% and 36.64% improvement in dystonia with a 17.37% and 28.86% reduction in disability at 6 months and 12 months, respectively. There was a positive correlation between the absolute reduction of the motor score and improvement in disability of the patients at 6 months (rho = 0.865, p value 0.003). Conclusions: DBS in PD has an enormous role in reducing disease burden and achieving a sustainable therapeutic goal. [ABSTRACT FROM AUTHOR]

Idiopathic cervical dystonia (ICD) is by far the largest subgroup of dystonia. Still, its natural course is largely unknown. We studied the natural course of 100 ICD patients from our botulinum toxin clinics (age at ICD onset 45.8 ± 13.5 years, female/male ratio 2.0) over a period of 17.5 ± 11.5 years with follow-ups during botulinum toxin therapy and with semi-structured interviews. Two courses of ICD could be distinguished by symptom development of more or less than 6 months. ICD-type 2 was less frequent (19% vs 81%, p < 0.001), had a more rapid onset (8.7 ± 8.0 weeks vs 3.8 ± 3.5 years), a higher remission rate (92% vs 5%, p < 0.001) and a higher prevalence of excessive psychological stress preceding ICD (63% vs 1%, p < 0.001). In both ICD-types, the plateau phase was non-progressive. Significant differences in patient age at ICD onset, latency and extent of remission, female/male ratio and prevalence of family history of dystonia could not be detected. ICD is a non-progressive disorder. ICD-type 1 represents the standard course. ICD-type 2 features rapid onset, preceding excessive psychological stress and a high remission rate. These findings will improve prognosis, treatment strategies and understanding of underlying disease mechanisms. They contradict the widespread fear of patients of a constant and continued decline of their condition. Excessive psychological stress may be an epigenetic factor triggering the manifestation of genetically predetermined dystonia. [ABSTRACT FROM AUTHOR]

Levodopa is used to treat hyperkinetic movements in children with dopa-responsive dystonia. However, levodopa may also be helpful in treating other forms of dystonia when used beyond a brief trial period. We performed a retrospective review of all children referred to our institution for evaluation of generalized dystonia and subsequently treated with carbidopa-levodopa. Motor function was assessed using video recordings and examination notes, quantified with the Burke-Fahn-Marsden Dystonia Rating Scale. Long-term treatment with carbidopa-levodopa moderately improved motor function, whereas short-term use did not. Carbidopa-levodopa was well tolerated without untoward effects. Dystonia is a significant cause of disability with limited effective treatment options. Published work is restricted but generally supports the findings of this review. A well-controlled study to examine the utility of carbidopa-levodopa treatment for dystonia is needed. [ABSTRACT FROM AUTHOR]

The diagnosis of functional dystonia is challenging because it is difficult to distinguish functional dystonia from other types of dystonia. After diagnostic explanation, multidisciplinary care is recommended, but some patients are resistant to treatments. We used motor blocks in three patients with severe resistant functional dystonia of the upper limbs to test (i) whether joint contracture was present and (ii) whether motor blocks have a therapeutic effect on functional dystonia. Patient 1 showed a good and sustained therapeutic response, Patient 2 experienced a resolution of the dystonic posture that lasted for 10 days, and Patient 3 experienced no effect. Motor blocks may be a useful therapeutic option in chronic treatment‐resistant functional dystonia. The treatment effect might be achieved through the experience of normal positioning and functioning of the limb. [ABSTRACT FROM AUTHOR]

Objectives: Adult‐onset idiopathic laryngeal dystonia (LD) can be associated with the risk of spread to muscles in the body. Subjects with extralaryngeal onset of dystonia have exhibited spread to the larynx. Previous studies analyze the spread of other dystonias but emphasis has not been placed on LD. The objective was to identify demographic and clinical factors contributing to the spread of dystonia to and from the larynx. Methods: Data were obtained from the Dystonia Coalition (DC)‐patients from 49 international clinical centers. Clinical and demographic data was taken from 143 out of 409 patients with diagnosed LD. Patient criteria included adult‐onset LD diagnosed on exam with no co‐morbid neurologic conditions and no dystonia in other locations. Results: Among the 143 patients, 94 (65.7%) patients were diagnosed with focal laryngeal onset, with the remainder having extralaryngeal onset. Family history and age at study were statistically significant indicators of a patient developing laryngeal versus extralaryngeal onset of dystonia. Among the laryngeal onset group, 21 cases (22.3%) had an average time of 5.81 ± 5.79 years to spread from diagnosis, most commonly to neck (61.9%). Among extralaryngeal onset patients, mean time of larynx spread was 7.92 ± 7.737 years, most commonly to neck (22.7%). Conclusions: Our data indicates approximately a quarter of patients with laryngeal‐onset dystonia will exhibit spread. There were no demographic or clinical factors that were statistically predictive of the likelihood of spread from larynx. Patients with dystonia elsewhere in the body should be counseled on the possibility of spread to larynx, and vice versa. Level of Evidence: 4 Laryngoscope, 134:2295–2299, 2024 [ABSTRACT FROM AUTHOR]