Showing papers in "Tremor and other hyperkinetic movements in 2022"

Movement Disorders in Multiple Sclerosis: An Update

Abstract: Background: Multiple sclerosis (MS), a subset of chronic primary inflammatory demyelinating disorders of the central nervous system, is closely associated with various movement disorders. These disorders may be due to MS pathophysiology or be coincidental. This review describes the full spectrum of movement disorders in MS with their possible mechanistic pathways and therapeutic modalities. Methods: The authors conducted a narrative literature review by searching for ‘multiple sclerosis’ and the specific movement disorder on PubMed until October 2021. Relevant articles were screened, selected, and included in the review according to groups of movement disorders. Results: The most prevalent movement disorders described in MS include restless leg syndrome, tremor, ataxia, parkinsonism, paroxysmal dyskinesias, chorea and ballism, facial myokymia, including hemifacial spasm and spastic paretic hemifacial contracture, tics, and tourettism. The anatomical basis of some of these disorders is poorly understood; however, the link between them and MS is supported by clinical and neuroimaging evidence. Treatment options are disorder-specific and often multidisciplinary, including pharmacological, surgical, and physical therapies. Discussion: Movements disorders in MS involve multiple pathophysiological processes and anatomical pathways. Since these disorders can be the presenting symptoms, they may aid in early diagnosis and managing the patient, including monitoring disease progression. Treatment of these disorders is a challenge. Further work needs to be done to understand the prevalence and the pathophysiological mechanisms responsible for movement disorders in MS.

Tremor in Parkinson’s Disease: From Pathophysiology to Advanced Therapies

Abstract: Background: Tremor is one of the most prevalent symptoms in Parkinson’s Disease (PD). The progression and management of tremor in PD can be challenging, as response to dopaminergic agents might be relatively poor, particularly in patients with tremor-dominant PD compared to the akinetic/rigid subtype. In this review, we aim to highlight recent advances in the underlying pathogenesis and treatment modalities for tremor in PD. Methods: A structured literature search through Embase was conducted using the terms “Parkinson’s Disease” AND “tremor” OR “etiology” OR “management” OR “drug resistance” OR “therapy” OR “rehabilitation” OR “surgery.” After initial screening, eligible articles were selected with a focus on published literature in the last 10 years. Discussion: The underlying pathophysiology of tremor in PD remains complex and incompletely understood. Neurodegeneration of dopaminergic neurons in the retrorubral area, in addition to high-power neural oscillations in the cerebello-thalamo-cortical circuit and the basal ganglia, play a major role. Levodopa is the first-line therapeutic option for all motor symptoms, including tremor. The addition of dopamine agonists or anticholinergics can lead to further tremor reduction. Botulinum toxin injection is an effective alternative for patients with pharmacological-resistant tremor who are not seeking advanced therapies. Deep brain stimulation is the most well-established advanced therapy owing to its long-term efficacy, reversibility, and effectiveness in other motor symptoms and fluctuations. Magnetic resonance-guided focused ultrasound is a promising modality, which has the advantage of being incisionless. Cortical and peripheral electrical stimulation are non-invasive innovatory techniques that have demonstrated good efficacy in suppressing intractable tremor.

One Side of the Story; Clues to Etiology in Patients with Asymmetric Chorea

Abstract: Background: Chorea can be due to a large number of etiologies. Unilateral chorea is classically related to a contralateral structural lesion, e.g. of the putamen or subthalamic nucleus, however, based upon personal impressions, we have observed that systemic disease, in particular metabolic or autoimmune conditions, can also lead to a unilateral or markedly asymmetric presentations. We sought to investigate this impression by reviewing the literature. Methods: A PubMed search was conducted using the terms asymmetric” AND “chorea” OR “hemichorea” OR “unilateral” AND “chorea” OR “monochorea” OR “right greater than left” AND “chorea” OR “left greater than right” AND “chorea” OR “right more than left” AND “chorea” OR “left more than right” AND “chorea” as well as “hemiballismus” NOT “stroke” NOT “infarct” NOT “dyskinesia. A total of 243 sources were felt to meet criteria and were reviewed. Results: The most common etiology of reported hemi- or asymmetric chorea was diabetic non-ketotic hyperglycemic hemichorea/hemiballismus. Other common diagnoses were Sydenham’s disease, antiphospholipid syndrome and drug-induced chorea. The vast majority of patients with hemi- or asymmetric chorea had acquired rather than genetic, degenerative or congenital causes. Conclusion: Despite the potential limitations of our literature review, the evidence presented here supports the observation that the vast majority of asymmetric or unilateral chorea presentations are due to acquired causes, and in this situation an exhaustive search for reversible etiology should be undertaken. However, presentation with symmetric, generalized chorea does not exclude reversible causes, and investigations should address these in addition to genetic and neurodegenerative etiologies.

The Conundrum of Dystonia in Essential Tremor Patients: How does One Classify these Cases?

Abstract: Background: The relationship between essential tremor (ET) and dystonia has been long debated and the boundaries between these disorders remain unclear. Here, we highlight the diagnostic uncertainty that can arise when observing dystonic postures in patients who have received ET diagnoses. Methods: An international panel of seven movement disorders neurologists from five countries reviewed the clinical history and videotaped neurological examinations of five individuals diagnosed with ET who also had various features of dystonia on neurological examination. Experts were instructed to assign diagnoses and provide their rationale for diagnostic assignments. Results: The five cases each exhibited a variety of abnormal postures. These were observed by all experts, and interpreted as dystonic postures by six experts. According to six of seven experts, all five cases had ET. One expert classified all cases as dystonic tremor rather than ET. One case had cervical dystonia, and five of seven experts assigned dual diagnoses of ET and dystonia in that case. The assignment of dystonia diagnoses was variable among the other four cases, with two to three experts assigning this diagnosis in each case, underscoring differences in diagnostic interpretation of dystonic postures on examination. Conclusions: This study draws attention to some of the differences between experts in assigning diagnoses of ET or dystonia to individuals with ET and abnormal postures. The goal here was not necessarily to build consensus, but to raise issues, highlight areas of uncertainty, and identify areas of common vs. differentiated thought. Several questions for additional research were also raised.

Rationale and Evidence for Peripheral Nerve Stimulation for Treating Essential Tremor

Abstract: Background: There is growing recognition of peripheral stimulation techniques for controlling arm symptoms in essential tremor (ET). Recently, the FDA gave clearance to the Cala system, a device worn around the wrist to treat arm tremors. The Cala system stimulates the sensory afferents of the peripheral nerves with high-frequency pulses. These pulses are delivered to the median and radial nerves alternately at the tremor frequency of the individual patient. Methods: The PubMed database was searched using the terms (“Essential Tremor”[Mesh] OR “essential tremor” [Title/Abstract] OR “tremor” [Title/Abstract]) AND (“peripheral arm stimulation” [Title/Abstract] OR “Cala device” [Title/Abstract] OR “sensory afferent stimulation” [Title/Abstract] OR “afferent stimulation” [Title/Abstract] OR “arm stimulation” [Title/Abstract] OR “peripheral nerve stimulation” [Title/Abstract]). Results: The search yielded 54 articles. Many studies discussed the rationale and various strategies for peripheral modulation of tremor. While the Cala system was found to be safe and well-tolerated in ET, data on efficacy revealed mixed findings. In a large randomized, blinded trial (n = 77), the primary outcome evaluated with spiral drawing task did not improve but the secondary outcomes reflected by the arm tremor severity and the activities of the daily living score revealed 20–25% improvements. A subsequent trial (n = 323) found that the in-home use of the Cala device led to improvements of similar magnitude lasting for at least three months but the clinical assessments were open-labeled. Discussion: Peripheral stimulation techniques are promising therapeutic modalities for treating ET symptoms. Stimulation of sensory afferent nerve fibers at the wrist can potentially modulate the peripheral and central components of the tremor network. Although the Cala system is user-friendly, safe, and well-tolerated, the current clinical evidence on the efficacy is inconsistent and insufficient. Thus, more data is warranted for implementing peripheral nerve stimulation as a standard of care for ET. Highlights The current review discusses the rationale, background, and potential mechanisms for using peripheral arm stimulation devices for treating ET. The Cala system is a wrist-worn peripheral nerve stimulation device that received FDA clearance to treat arm tremors. The current review evaluates the evidence for the safety and efficacy of using the Cala system and similar devices in clinical practice.

Surgical Outcomes in Rare Movement Disorders: A Report of Seventeen Patients from India and Review of Literature

Abstract: Background: Rare movement disorders (RMDs) throw remarkable challenges to their appropriate management particularly when they are medically refractory. We studied the outcome of functional neurosurgery among patients with RMDs. Methods: Retrospective chart-review from 2006 to 2021 of patients with RMDs who underwent either Deep brain Stimulation (DBS) or lesional surgeries in the department of Neurology and Neurosurgery at a tertiary care centre. Results: Seventeen patients were included. Generalized dystonia (11 patients, 64.7%) and tremor (5 patients, 29.4%) were the most common indication for surgery whereas, Wilson’s disease (8 patients, 47.1%) and Neurodegeneration with brain iron accumulation (5 patients, 29.4%) were the most common aetiology. Sixteen patients (94.1%) had objective clinical improvement. Significant improvement was noted in the dystonia motor scores both at 6-months and 12-months follow-up (n = 11, p-value of <0.01 and 0.01 respectively). Comparison between DBS and lesional surgery showed no significant difference in the outcomes (p = 0.95 at 6-months and p = 0.53 at 12-months), with slight worsening of scores in the DBS arm at 12-months. Among five patients of refractory tremor with Wilson’s disease, there was remarkable improvement in the tremor scores by 85.0 ± 7.8% at the last follow-up. Speech impairment was the main complication observed with most of the other adverse events either transient or reversible. Discussion: Surgical options should be contemplated among patients with disabling medically refractory RMDs irrespective of the aetiology. Key to success lies in appropriate patient selection. In situations when DBS is not feasible, lesional surgeries can offer an excellent alternative with comparable efficacy and safety.

KCNN2 Mutation in Pediatric Tremor Myoclonus Dystonia Syndrome with Electrophysiological Evaluation

Abstract: Background: Here we combine clinical, electrophysiological, and genetic findings to phenotype an unusual childhood movement disorder in a patient with a rare form of KCNN2 mutation. Case Report: A 10-year-old male presented with a clinical syndrome of tremor and myoclonus. Electrophysiology demonstrated muscle activity indicative of myoclonus dystonia, an observation that was not appreciated clinically. Genetic testing revealed an abnormality in the KCNN 2 gene, not present in the parents, known to cause dystonia, as the etiology. Discussion: The value of utilizing noninvasive, electrophysiological recording in pediatric movement disorders expands the precision of diagnosis, potentially informing treatment when correlated with clinical and genetic findings.

NUS1 and Epilepsy-myoclonus-ataxia Syndrome: An Under-recognized Entity?

Abstract: Background: Variants of the NUS1 gene have recently been linked to a spectrum of phenotypes including epilepsy, cerebellar ataxia, cortical myoclonus and intellectual disability (ID), and primary congenital defects of glycosylation. Case Report: We report a case of myoclonus epilepsy, mild cerebellar ataxia, and ID due to a new de-novo NUS1 missense variant (c.868C>T, p.R290C), and review the current literature of NUS1-associated clinical phenotypes. Discussion: Pathogenic variants of NUS1 are found in a rapidly growing number of cases diagnosed with myoclonus epilepsy and/or myoclonus-ataxia syndrome. NUS1 should be included in the genetic screening of undiagnosed forms of myoclonus, myoclonus-ataxia, and progressive myoclonus epilepsies.

Clinical and Radiological Follow-Up of a Pfizer-BioNTech COVID-19 Vaccine-Induced Hemichorea-Hemiballismus

Abstract: Background: Hemichorea-hemiballismus is a rare hyperkinetic movement disorder. Case Report: A 90-year-old male developed left hemichorea-hemiballismus after his second dose of the Pfizer-BioNTech COVID-19 vaccine. A wide range of investigations including magnetic resonance imaging did not reveal an alternative cause. [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed increases in right putamen fixation compared to the left side. The patient showed significant improvement after five days of intravenous corticosteroids, with a normal FDG-PET. Discussion: This hemichorea-hemiballismus case shows dynamic restoration of putamen metabolism mirroring clinical evolution after administration of corticosteroids, suggesting an autoimmune COVID-19 vaccine-induced reaction.

Spectrum of Movement Disorders in Niemann-Pick Disease Type C

Abstract: Introduction: Niemann-Pick disease type C (NPC) is an autosomal recessive neurovisceral lipid storage disorder caused by mutations in the NPC 1 or 2 genes. Movement disorders can occur as the first symptom and as predominant symptom mainly in juvenile-onset. The frequency and heterogeneity of movement disorders in NPC are not well described. We studied the frequency and spectrum of movement disorders in patients with NPC of different age of onset. Methods: Retrospective chart review of patients with NPC diagnosed based on the Suspicion Index tool and demonstration of foamy macrophages/sea-blue histiocytes in bone marrow aspirate. Results: We report 9 cases of NPC with 2 patients of late-infantile, 4 juvenile-onset and 3 of adult-onset. The mean age at onset of symptoms was 11.7 ± 10.4 (range 4–38 years) and the median duration of illness was 4 years. Vertical supranuclear gaze palsy (VSGP) was noted in 8 patients and VSGP with slowing of saccade in 1 patient. Splenomegaly was seen in 5 patients. Movement disorders as the first symptom occurred in 4 patients. Dystonia was the first symptom in 2 patients and cerebellar ataxia in 2 patients. Cerebellar ataxia occurred during the course of illness in 5 patients, dystonia in 6 patients. One patient with late-infantile NPC had stimulus-sensitive myoclonus. Conclusion: Movement disorders are common in NPC and occur as a presenting symptom. Cerebellar ataxia and dystonia are the most common movement disorder in NPC. Vertical supranuclear gaze palsy along with the movement disorders should lead to clinical suspicion of NPC.

Apraxia of Eyelid Opening and Blepharospasm in Two Spinocerebellar Ataxia Type 3 Patients

Abstract: Background: Neuroophthalmological phenotypical particularities of SCA3. Phenomenology: Eyelid opening apraxia and asymmetrical blepharospasm. Educational Value: To illustrate the phenomenology for purposes of education.

Accidental Falls in Patients with Hyperkinetic Movement Disorders: A Systematic Review

Abstract: Background: The significance of falls and their repercussions in Parkinson’s disease has been extensively researched. However, despite potentially serious effects on health and quality of life and negative impact on the healthcare system, there is not a sufficient understanding of the role of falls in hyperkinetic movement disorders (HKMDs). This review aims to provide an overview of the prevalence of falls, injuries, and preventive measures in the most common HKMDs. Methods: Studies up to May 1, 2022 were searched in PubMed using Medical Subjects Headings of relatively prevalent HKMDs associated with the terms “accidental falls”, “injuries”, “fractures”, and “accident prevention”. Results: In our review of 37 studies out of 155, we found evidence that for several HKMDs, such as spinocerebellar ataxia, essential tremor, Huntington’s disease, and dystonia, fall risk is increased. Falls were reported in up to 84% of spinocerebellar ataxia patients, 59% of essential tremor patients, and 79% of Huntington’s patients, with 65% of the latter falling frequently. Injuries occurred in up to 73% in Huntington and 74% in ataxia patients. Most of the common diseases characterized by HKMDs were investigated for both fall causes and consequences, but prevention studies were limited to spinocerebellar ataxia and Huntington’s disease. Discussion: The limited available data suggest that patients with several HKMDs can be considered to be at increased risk of falling and that the consequences can be serious. As a result, physicians should be advised to include fall exploration in their routine workup and provide advice for safer mobility. In general, more research into fall-related concerns in HKMDs is necessary. Highlights: In contrast to Parkinson’s disease, the prevalence of accidental falls, their repercussions, and preventive strategies are under-investigated in hyperkinetic movement disorders (HKMDs). Several HKMDs such as essential tremor, ataxia, and Huntington’s disease have reported fall rates of up to 84% and fall-related injury rates of up to 74%. Therefore, routine examinations of HKMD patients should include a fall exploration and provide advice on safe mobility.

Clinical, Radiological, and Genetic Profile of Spinocerebellar Ataxia 12: A Hospital-Based Cohort Analysis

Abstract: Introduction: Spinocerebellar ataxia type-12 (SCA12) is a rare form of SCA, most commonly reported from the Indian Agarwal and related families. In this study we describe the clinical, genetic, and radiological characteristics of a sizeable cohort of genetically proven SCA12. Methods: A retrospective chart-review of the genetically confirmed SCA12 patients from our centre. The demographic, clinical, and investigation findings were reviewed. Correlation of expanded repeats length with various demographic and clinical features were studied. Results: A total of 49 patients (34 males, 42 families) were included of which 79.6% belonged to Agarwal community. The mean age at onset and age at presentation were 46.38 ± 11.7 years and 53.16 ± 12.78 years respectively. The most common initial symptom was tremor (73.5%), followed by ataxia (18.4%). At presentation, 95.9% of the patients had tremor with predominant distribution in the bilateral upper limbs (85.7%). At presentation, 73.5% of patients had ataxia and 22.4% had cognitive dysfunction. The mean CAG repeat length in PPP2R2B in the expanded allele was 53.26 ± 6.10 (40–72). The lowest pathogenic expanded repeat sizes in PPP2R2B recorded in our cohort was 40 & 42 repeats from two patients with a consistent clinical phenotype. Another unusual phenotype was the presence of prominent myoclonus. There was no significant correlation between the age at onset of symptoms and the repeat size of CAG repeat. Conclusion: SCA12 is not confined to a single ethnicity. Upper limb tremor and ataxia were the most common presentation. Unusual presentation may cause diagnostic confusion especially when recorded in patients from non-Aggarwal families.

Diagnostic Tips from a Video Series and Literature Review of Patients with Late-Onset Tay-Sachs Disease

Abstract: Background: Late-Onset Tay-Sachs (LOTS) disease is a rare, progressive neurological condition that can dramatically affect the life of these patients. The diagnosis of LOTS is easily missed because of the multifaced presentation of these patients, who can initially be assessed by neuromuscular or movement disorder specialists, or psychiatrists. Clinical trials are now becoming available for LOTS. Therefore, early diagnosis can be detrimental for these patients and for insuring informative research outcomes. Methods: We characterized a cohort of nine patients with LOTS through a detailed clinical and video description. We then reviewed the available literature regarding the clinical description of patients with LOTS. Our findings were summarized based on the predominant phenotype of presentation to highlight diagnostic clues to guide the diagnosis of LOTS for different neurology specialists (neuromuscular, movement disorders) and psychiatrist. Results: We described a cohort of 9 new patients with LOTS seen at our clinic. Our literature review identified 76 patients mainly presenting with a neuromuscular, cerebellar, psychiatric, stuttering, or movement disorder phenotype. Diagnostic tips, such as the triceps sign, distinct speech patterns, early psychiatric presentation and impulsivity, as well as neurological symptoms (cerebellar or neuromuscular) in patients with a prominent psychiatric presentation, are described. Discussion: Specific diagnostics clues can help neurologists and psychiatrists in the early diagnosis of LOTS disease. Our work also represent the first video presentation of a cohort of patients with LOTS that can help different specialists to familiarize with these features and improve diagnostic outcomes. Highlights Late-Onset Tay-Sachs (LOTS) disease, a severe progressive neurological condition, has multifaced presentations causing diagnostic delays that can significantly affect research outcomes now that clinical trials are available. We highlight useful diagnostic clues from our cohort (including the first video representation of a LOTS cohort) and comprehensive literature review.

Evolving Concepts in Our Understanding and Treatment of Holmes Tremor, Over 100 Years in the Making

Abstract: Holmes Tremor (HT) is an irregular, slow-frequency (<4.5 Hz) tremor characterized by a combination of resting, postural, and action tremors mostly of the upper extremities. Symptoms of HT typically emerge 4 weeks to 2 years after a brain injury caused by a spectrum of etiologies. HT pathophysiology is thought to result from aberrant collateral axonal sprouting and synaptic dysfunction following neuronal damage. To date, the dopaminergic nigrostriatal system, cerebello-thalamo-cortical pathway, and dentate-rubro-olivary pathway have all been implicated in the clinical manifestations of HT. The diversity of HT etiologies usually requires a personalized treatment plan. Current treatment options include carbidopa-levodopa, levetiracetam, and trihexyphenidyl, and surgical management such as deep brain stimulation in selected medication-refractory patients. In this review we discuss the pathophysiology, etiology, neuroimaging, and the latest clinical guidelines for care and management of HT.

Treatment Patterns in Essential Tremor: A Retrospective Analysis

Abstract: Background: Although first line therapies for essential tremor have been identified from small clinical trials, responses are variable. We conducted a survey of tremor management in a large sample of ET cases. Methods: The Movement Disorders Clinical Case Registry within a US Veterans Health Administration medical center was used to identify 1468 patients with ET. Results: Of 1468 charts reviewed, 1074 (73.19%) met criteria for ET with characterization of temporal course and treatment; 291/1074 subjects (27.1%) did not receive any treatment. Almost half (500/1074; 46.6%) of the patients received monotherapy, 196/1074 (18.2%) two, 66/1074 (6.1%) three, and 21/1074 (2.0%) four or more medications. Of all prescriptions, primidone was the most used (546/1172; 46.6%), followed by propranolol (419; 35.8%), topiramate (122; 10.4%) and gabapentin (35; 3.0%). Medication response was available for a total of 1030 prescriptions, of which 138 (13.4%) were discontinued due to side effects; 180 (17.5%) prescriptions were ineffective. Furthermore, 52/1074 patients (4.8%) were treated with botulinum toxin injections and 41/1074 (3.8%) underwent deep brain stimulation surgery. Discussion: Our data suggest that more widespread recognition of limitations underlying conventional approaches, as well as increased referrals for nonpharmacological therapies, may be necessary to achieve improved outcomes in ET populations.

Advance Directive Documentation in a Huntington’s Disease Clinic: A Retrospective Chart Review

Abstract: Background: Advance care planning (ACP) benefits patients and caregivers, yet it is underutilized and little is known about ACP in Huntington’s disease (HD) clinics. This study sought to determine the percentage of charts with AD documentation within an HD clinic. Methods: A retrospective chart review was conducted on a randomly selected sample of charts within an HD clinic. HD patients ≥18 y/o with a positive genetic test (≥40 CAG repeats) seen between January 2018 and June 2021 were included. Charts were reviewed for documentation of ADs either in provider notes or in the electronic medical records (EMR). Results: Ninety-one charts were reviewed (n = 91). Twenty-two charts (24.2%) mentioned a completed AD within a provider’s note; however, only nine (9.9%) had an AD available in the EMR. Cognitive status, primary insurance type, presence of dysphagia, and stage of disease were associated with documentation of completed ADs within a provider’s note. Discussion: The rate of completed ADs mentioned in a provider’s note (24.2%) was significantly lower than rates of AD completion in a previous study within the HD population (38%). Additional studies focused on improving rates AD completion are needed. Highlights Most patients with Huntington’s disease do not have documentation of completed advance directives (ADs) within their medical chart. In a retrospective chart review 24.2% of patients seen in a specialty HD clinic had documentation of ADs in a provider’s note and 9.9% had ADs available within the EMR.

Risk of Drug-induced Movement Disorders with Newer Antipsychotic Agents

Abstract: Background: The last decade has seen development of numerous novel antipsychotic drugs with unique mechanisms including long-acting formulations for clinical use. A comparative assessment of these new drugs with each other and previous antipsychotics have not been performed with regards to risk for drug-induced movement disorders (DIMD). Methods: Medline was searched from January 2010 to February 2022 for primary research articles and review articles in English using the search terms “extrapyramidal” and “tardive” with individual drug names of novel antipsychotics. Results: We identified articles describing the risk of DIMD with 6 novel antipsychotics, 4 novel formulations, and 3 experimental antipsychotics. Both short- and long-term data generally showed comparable to lower risk of DIMD with novel antipsychotics and recent long-acting formulations compared to previously marketed antipsychotics. Discussion: Several novel antipsychotics, particularly lumateperone and pimavanserin, show promise in being able to treat psychosis while reducing the risk of DIMD. Long-acting paliperidone may reduce risk of DIMD while other long-acting injectable formulations of SGA have similar risk of DIMD compared to oral formulations. New drug targets for treating psychosis without dopamine blockade also show promise.

Clinical and Radiological Follow-Up of a Pfizer-BioNTech COVID-19 Vaccine-Induced Hemichorea-Hemiballismus; Insights Into Mechanisms of Basal Ganglia Dysfunction

Abstract: Asymmetric chorea unrelated to structural lesions is typically due to systemic etiologies, such as metabolic, autoimmune, or other inflammatory disorders. This is an editorial commenting on a paper by Batot C, Chea M, Zeidan S, et al. Clinical and radiological follow up of Pfizer-BioNTech COVID-19 vaccine-induced hemichorea-hemiballismus. Tremor and Other Hyperkinetic Movements; 2022; 12(1). DOI: https://doi.org/10.5334/tohm.688. A 90-year-old patient is reported who developed hemichorea shortly after his second vaccination against COVID-19. Hypometabolism was noted in the contralateral striatum. This case provides potential insights and raises questions about mechanisms of immune-mediated hemichorea.

Case report – Asterixis Post High Frequency Focused-Ultrasound Thalamotomy

Abstract: Background: High frequency focused ultrasound is used for treatment of essential tremor. Side effects associated with the procedure may resolve over time. We report a case of negative myoclonus, which has not been reported with this procedure. Case report: A 73-year-old left-handed man underwent focused ultrasound thalamotomy for treatment of essential tremor. Immediately post procedure he was noted to have negative myoclonus in the treated limb. This side effect resolved over the course of 6 months. Discussion: Although asterixis has been associated with thalamic infarcts in the past, this has not yet been reported in the literature with MRgFUS procedure and is a novel observation. Occupational and physical therapy may be considered to address this side effect. It is important to counsel patients about the rare occurrence of this complication of therapy but also its potential for complete resolution over time.

Parakinesia Brachialis Oscitans – a Rare Post-Stroke Phenomenon

Abstract: Background: Abnormal involuntary movement of paralyzed upper limb during yawning is a rare phenomenon termed as parakinesia brachialis oscitans. Case Report: We describe a 59-year-old gentleman with abnormal involuntary movement of paralyzed right upper limb during yawning 2 weeks following ischemic stroke of left middle cerebral artery territory. Discussion: This is a rare post-stroke phenomenon and its pathophysiological mechanism is poorly understood but this entity highlights possible preserved extrapyramidal pathway which might help in rehabilitating stroke survivors.

Measurement Issue in Antecollis

Abstract: Background: Antecollis is defined as an involuntary forward flexion of the neck. Previous reports have measured the neck flexion angles based on the line perpendicular to the ground. This led to an inflation of the neck flexion angles in patients who had combined forward truncal flexions, especially upper camptocormia. Methods: We examined the neck flexion angles and the upper camptocormia angle in the published photographs of antecollis. MEDLINE search was conducted using the following search terms: antecollis OR anterocollis. Lateral-view photographs of patients diagnosed with antecollis were collected. Neck flexion angles were measured with the classic ‘perpendicular method’ and the ‘antecollis method’ we developed. Results: Nine patient photographs were identified. While antecollis was the only described postural abnormality in eight cases, these patients exhibited upper camptocormia angles of 45° or larger. The mean neck flexion angle measured with the antecollis method was 49.7°, while the perpendicular method yielded 103.4°. Discussion: Upper camptocormia should be considered in the evaluation of antecollis. We propose a new method to measure neck flexion in relation to the torso, instead of the vertical line.

A New Pathologic KMT2B Variant Associated with Childhood Onset Dystonia Presenting as Variable Phenotypes among Family Members

Abstract: Background: KMT2B-related dystonia is a primarily childhood-onset movement disorder characterized by progressive dystonia, spasticity, and developmental delay. A minority of individuals possess an inherited KMT2B variant. Case Report: As a child, the proband experienced mild developmental delay and laryngeal dystonia which progressed to generalized dystonia. Patellar hyperreflexia, postural tremor, and everted gait were documented. Whole exome sequencing identified a heterozygous pathogenic KMT2B variant in the proband, proband’s sister, and proband’s mother who had milder presentations. Discussion: This novel KMT2B variant reflects intrafamilial variable expressivity in KMT2B-related dystonia. Further identification of variants will allow for better appreciation of the phenotypic spectrum.

Quality and Reliability Analysis of Essential Tremor Disease Information on Social Media: The Study of YouTube

Abstract: Background: YouTube has evolved into an important educational tool and information source for patients and their families. YouTube videos have the potential to influence the patients’ health-related diagnosis and treatment decision-making. We aimed to evaluate the quality and usefulness of videos on essential tremor available on YouTube using quantitative instruments. Methods: Video searches were performed by typing the keywords ‘essential tremor’, ‘postural tremor’, ‘action tremor’, ‘essential tremor hand’, and ‘essential tremor head’ into the YouTube search bar. The top 30 videos were reviewed for each search term. The videos were analyzed by two independent raters using the DISCERN and Global Quality Scale (GQS) scoring systems. Qualitative and quantitative data were recorded for each video. Results: A total of 83 videos were analyzed. The mean DISCERN score was 41.96 out of 75 possible points, and the mean GQS score was 2.97 out of 5 possible points. Twelve percent of the videos were categorized as very poor, 38.6% as poor, 20.5% as fair, 19.3% as good, and 9.6% as excellent. The videos containing qualitative content features, such as clear information, symptoms, etiology, diagnosis, treatment, treatment response, epidemiology, diagrams, and radiological images had significantly higher DISCERN and GQS scores. Discussion: We consider that reliable and useful content is not provided on YouTube for individuals searching for information on essential tremor. We listed the best-quality videos on this topic as a reference for healthcare practitioners and patients. Patients should always verify information provided in such videos through more reliable sources.

Suppression of Axial Tremor by Deep Brain Stimulation in Patients with Essential Tremor: Effects on Gait and Balance Measures

Abstract: Background: Deep brain stimulation (DBS) of the ventralis intermedius (VIM) nucleus of the thalamus has been successful in mitigating upper limb tremor, but the effect on gait and balance performance is unclear. Here, we aim to examine the effectiveness of VIM DBS on stride length variability, sway path length, and task-relevant tremor of various body segments in essential tremor (ET). Methods: Seventeen ET individuals treated with DBS (ET DBS) and 17 age-and sex-matched healthy controls (HC) performed a postural balance and overground walking task. In separate and consecutive visits, ET DBS performed gait and balance tasks with DBS ON or OFF. The main outcome measures were sway path length, stride length variability, and tremor quantified from upper limb, lower limb, upper and lower trunk (axial) during the gait and balance tasks. Results: With DBS OFF, ET DBS exhibited significantly greater stride length variability, sway path length, and tremor during gait and balance task relative to HC. Relative to DBS OFF, DBS ON reduced stride length variability and sway path length in ET DBS. The DBS-induced reduction in stride length variability was associated with the reduction in both upper trunk tremor and upper limb tremor. The DBS-induced reduction in sway path length was associated with the reduction in upper trunk tremor. Discussion: The findings of this study revealed that VIM DBS was effective in improving gait and balance in ET DBS and that improvements in gait and postural balance were associated with a reduction of axial tremor during the tasks. Highlights: ET patients exhibit tremor in various body locations during gait and balance. DBS reduced stride length variability and sway path length. DBS-induced improvements in gait and balance were associated with reduction in axial tremor.

A Case of New Onset Cervical Dystonia in Pregnancy

Abstract: Background: Though uncommon, primary movement disorders can occur in pregnancy, the most common being restless legs syndrome and chorea gravidarum [1]. New onset dystonia in pregnancy has been reported four times previously with a resolution of symptoms within six months of delivery [2345]. Exacerbation of pre-existing movement disorders and the onset of de novo movement disorders during pregnancy support the hypothesis that female sex hormones play an important role in the regulation of basal ganglia circuitry. Case Report: Here we describe a case of new-onset cervical dystonia during pregnancy with persistence of symptoms after delivery. Discussion: The phenotypic overlap between this case and previously reported cases further establishes dystonia gravidarum as a distinct clinical entity.

Brain Donation Decisions as Disease Specific Behaviors: An Elucidation of the Donation Process in the Context of Essential Tremor

Abstract: Brain donation is a challenging process, comprising four sequential stages: (1) the brain donation decision, (2) pre-mortem arrangements and follow up, (3) specimen collection and (4) tissue processing. It is important to understand the factors that are pertinent to each stage. Currently, there is extensive information on factors that involve donor’s personal and cultural backgrounds and how these could affect the process. However, little is known about disease-specific factors that influence the process. The Essential Tremor Centralized Brain Repository was established in 2003, and after nearly 20 years of collecting essential tremor (ET) brain tissue, we are well-positioned to discuss the brain donation process from a disease-specific standpoint. In the current manuscript, we discuss ET disease-specific factors that influence the first two stages of the brain donation process. We center our discussion around three points: (1) factors that influence the patient’s decision to donate, (2) the involvement of next of kin in the donation, and (3) the rationale for enrolling patients prospectively and evaluating them longitudinally before the anatomical gift takes place. This discussion shares our understanding of the background from which our repository operates and may be of value for other brain banks that study similar neurodegenerative diseases.

A Case of Lance-Adams Syndrome with Mixed Cortical and Reticular Reflex Myoclonus

Abstract: Background: Lance Adams syndrome is a chronic post-hypoxic myoclonus. Phenomenology Shown: This video abstract illustrates Lance Adams Syndrome with mixed cortical and reticular reflex myoclonus in a 32-year-old woman following respiratory arrest in the setting of an asthma attack, as well as improvement in her exam following pharmacologic management. Educational Value: Lance Adams syndrome can include both cortical and reticular reflex myoclonus features while interdisciplinary intervention and pharmacological treatment can improve symptomatology.

Real-World Evidence of Transcutaneous Afferent Patterned Stimulation for Essential Tremor

Abstract: Background: Transcutaneous afferent patterned stimulation (TAPS) is a prescription, wrist-worn device-delivered, non-invasive neuromodulation therapy for treatment of hand tremor in patients with essential tremor (ET). This retrospective post-market surveillance study evaluated real-world effectiveness of TAPS from patients using therapy on-demand for at least 90 days between August 2019 through June 2021. Methods: Demographics were summarized from TAPS prescriptions received from the patient’s healthcare provider. Therapy usage and effectiveness were analyzed from device logs, which included tremor measurements from onboard motion sensors. Tremor history and patient-reported outcomes were assessed from a voluntary survey. Results: A total of 321 patients (average age 71 years, 32% female) met the criteria for this analysis, 216 of whom had tremor measurements available for analysis and 69 of whom completed the survey. Total usage period ranged from 90 to 663 days, with 28% of patients using the device for over one year. Patients used therapy 5.4 ± 4.5 (mean ± 1 standard deviation) times per week. TAPS reduced tremor power by 71% (geometric mean) across all sessions, with 59% of patients experiencing >50% tremor reduction after their sessions. Eighty-four percent (84%) of patients who returned the voluntary survey reported improvement in at least one of eating, drinking, or writing, and 65% of patients reported improvement in quality of life. Self-reported device-related safety complaints were consistent with adverse events in prior clinical trials. Discussion: Real-world evidence is consistent with prior clinical trials and confirms TAPS provides safe and effective tremor control for many patients with ET. Future work assessing multi-year safety and effectiveness would be valuable to extend these data.