708 results match your criteria Myokymia


Demystifying the spontaneous phenomena of motor hyperexcitability.

Clin Neurophysiol 2021 May 13;132(8):1830-1844. Epub 2021 May 13.

UK Dementia Research Institute, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK; King's College Hospital NHS Foundation Trust, Denmark Hill, London, UK.

Possessing a discrete functional repertoire, the anterior horn cell can be in one of two electrophysiological states: on or off. Usually under tight regulatory control by the central nervous system, a hierarchical network of these specialist neurons ensures muscular strength is coordinated, gradated and adaptable. However, spontaneous activation of these cells and their axons can result in abnormal muscular twitching. Read More

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Disorders of the Fourth Cranial Nerve.

J Neuroophthalmol 2021 Jun;41(2):176-193

Department of Ophthalmology, University of Alabama School of Medicine (LBK, MSV, MT), Birmingham, Alabama; The Shiley Eye Institute, University of California San Diego (LBK), San Diego, California; and The Jules Stein Eye Institute, University of California, Los Angeles (JLD), Los Angeles, California.

Abstract: This review of disorders of the fourth cranial nerve includes discussion on anatomy, examination techniques, congenital and acquired etiologies, differential diagnosis, and management options. The findings of the superior oblique muscle on orbital MRI in patients with fourth nerve palsy have had a major impact on our understanding of this cranial neuropathy. In addition, briefly reviewed are rare disorders of the fourth nerve: superior oblique myokymia, Brown syndrome, and ocular neuromyotonia. Read More

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Morvan syndrome associated with LGI1 antibody: a case report.

BMC Neurol 2021 May 3;21(1):185. Epub 2021 May 3.

Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.

Background: Morvan syndrome (MoS) is a rare autoimmune syndrome associated with antibodies against two kinds of potassium channel proteins, contactin associated protein-like 2 (CASPR2) and leucine-rich glioma inactivated protein 1 (LGI1). MoS patients with only LGI1-antibody seropositivity have rarely been reported. Here, we describe a 64-year-old male MoS patient with only LGI1-antibody seropositivity. Read More

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Teaching Video NeuroImages: Infratentorial Multiple Sclerosis Relapse Presenting as Continuous Hemifacial Myokymia.

Neurology 2021 Apr 26. Epub 2021 Apr 26.

Department of Neurology, Hospital Egas Moniz, Centro Hospitalar Lisboa Ocidental, Portugal.

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Tacrolimus as a therapeutic option in patients with acquired neuromyotonia.

J Neuroimmunol 2021 Jun 7;355:577569. Epub 2021 Apr 7.

Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. Electronic address:

Objective: To analyze the clinical characteristics and outcomes of patients diagnosed with acquired neuromyotonia and who were treated with tacrolimus.

Methods: A single center, retrospective study was performed on patients with acquired meuromyotonia whose treatment included tacrolimus. The clinical information, antibody tests, and electromyography results were reviewed. Read More

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International veterinary canine dyskinesia task force ECVN consensus statement: Terminology and classification.

J Vet Intern Med 2021 May 26;35(3):1218-1230. Epub 2021 Mar 26.

Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany.

Movement disorders are a heterogeneous group of clinical syndromes in humans and animals characterized by involuntary movements without changes in consciousness. Canine movement disorders broadly include tremors, peripheral nerve hyperexcitability disorders, paroxysmal dyskinesia, and dystonia. Of these, canine paroxysmal dyskinesias remain one of the more difficult to identify and characterize in dogs. Read More

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Eribulin Mesylate-related Multifocal Demyelinating Neuropathy with Myokymia in a Breast Cancer Patient.

Intern Med 2021 Mar 8. Epub 2021 Mar 8.

Department of Neurology, Kobe City Medical Center General Hospital, Japan.

We herein report a 48-year-old woman receiving eribulin mesylate for breast cancer who presented with gait disorder, distal limb paresthesia, and weakness progressing monthly. A nerve conduction study indicated demyelination with multifocal conduction block. Considering the immune-mediated pathology of her condition, she was administered intravenous immunoglobulin. Read More

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Quantitative analysis of myokymic discharges in radiation versus nonradiation cases.

Muscle Nerve 2021 Jun 24;63(6):861-867. Epub 2021 Mar 24.

Department of Neurology, Mayo Clinic, Jacksonville, Florida, USA.

Introduction: Myokymic discharges are classically associated with nerve injury from prior radiation but may occur in other neuromuscular disorders. Using quantitative analysis we aimed to identify the spectrum of conditions in which myokymic discharges are present and determine if there are electrophysiological features that distinguish postradiation from nonradiation causes of myokymia.

Methods: We reviewed the clinical history of all patients examined in our electromyography labs with myokymic discharges recorded from June 2017 to February 2020. Read More

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Neurocysticercosis and movement disorders: A literature review.

Brain Circ 2020 Oct-Dec;6(4):225-241. Epub 2020 Dec 29.

Department of Medicine, Federal University of Fronteira Sul, Passo Fundo, RS, Brazil.

Neurocysticercosis (NCC) is a specific form of cysticercosis that affects the central nervous system. It is caused by the tapeworm , which is often found in pigs. NCC is considered one of the "great simulator/mimickers" of other diseases. Read More

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December 2020

Sustained atypical myokymia of the abductor pollicis brevis with a focal slowing of the median nerve motor axons at the wrist.

Clin Neurophysiol Pract 2021 17;6:36-40. Epub 2020 Dec 17.

Department of Neurology, Division of Clinical Neurophysiology, University of Iowa Health Center, 200 Hawkins Drive, Iowa City, IA 52242, USA.

Objective: We report a case of sustained atypical myokymia associated with short bursts of neuromyotonic discharges involving the abductor pollicis brevis (APB) muscle and describe a useful way of detecting a focal slowing involving a small number of median nerve motor fibers with a concentric needle using the filter setting for single fiber electromyography (EMG).

Methods And Results: A 62-year-old woman developed right thumb twitches at regular interval of 1.7-3. Read More

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December 2020

Gabapentin-Induced Myokymia: A Case Report.

Clin Neuropharmacol 2021 Mar-Apr 01;44(2):75-76

Department of Neurology, University of Texas Medical Branch, Galveston, TX.

Background: Gabapentin is a commonly used medication for neuropathic pain and epilepsy that is prescribed by a wide range of medical specialties. Adverse effects including asterixis and myoclonus have been described in patients with chronic kidney disease, but myokymia has not been previously reported.

Case Presentation: A 69-year-old man with a history of traumatic brain injury, peripheral neuropathy, amnesia, and posttraumatic stress disorder presented to the hospital after multiple falls attributed to acute onset muscle spasms. Read More

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January 2021

Musculoskeletal Features without Ataxia Associated with a Novel de novo Mutation in Impairing the Voltage Sensitivity of Kv1.1 Channel.

Biomedicines 2021 Jan 14;9(1). Epub 2021 Jan 14.

Paediatric Neurology and Neuromuscular Disorders Unit, IRCCS Institute "G. Gaslini", 80131 Genoa, Italy.

The gene encodes the α subunit of the voltage-gated Kv1.1 potassium channel that critically regulates neuronal excitability in the central and peripheral nervous systems. Mutations in have been classically associated with episodic ataxia type 1 (EA1), a movement disorder triggered by physical and emotional stress. Read More

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January 2021

[Five cases of post occupational chronic n-Hexane poisoning myokymia].

Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2020 12;38(12):929-930

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December 2020

Encephalopathy related to status epilepticus during sleep due to a de novo KCNA1 variant in the Kv-specific Pro-Val-Pro motif: phenotypic description and remarkable electroclinical response to ACTH.

Epileptic Disord 2020 Dec;22(6):802-806

Danish Epilepsy Center, Dianalund, Denmark, University of Copenhagen, Copenhagen, Denmark.

Although the classic phenotype of episodic ataxia type 1 (EA1) caused by variants in KCNA1 includes episodic ataxia and myokymia, further genotype-phenotype correlations are difficult to establish due to highly heterogeneous clinical presentations associated with KCNA1 pathogenic variants. De novo variants in the paralogous Pro-Val-Pro motif (PVP) of KCNA2, an essential region for channel gating, have been reported to be associated with severe epilepsy phenotypes, including developmental and epileptic encephalopathies (DEE). Here, we describe the first patient with a DEE who developed an encephalopathy related to status epilepticus during sleep (ESES) and cerebellar signs, harbouring a variant in the Kv-specific PVP motif of the KCNA1 gene. Read More

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December 2020

Continuous facial myokymia in multiple sclerosis.

Clin Case Rep 2020 Nov 16;8(11):2326-2327. Epub 2020 Jul 16.

Department of Neurology Warren Alpert Medical School of Brown University Providence RI USA.

Facial myokymia is a clinical sign that can occur as a manifestation of demyelinating lesions. As seen in our patient with multiple sclerosis, acute-onset continuous facial myokymia can be indicative of an active lesion and can have localizing value. Read More

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November 2020

Multifocal Motor Neuropathy with Persistent Conduction Block: The Seminal Case.

Eur Neurol 2020 11;83(6):639-642. Epub 2020 Nov 11.

Department of Anatomy and Department of Neuromuscular diseases, CHRU Besançon, University of Franche-Comté, Besançon, France,

Although multifocal motor neuropathy (MMN) is now recognized as a distinct, albeit rare, neurological condition, the path to its recognition was long and winding. This article provides an insight into the medical history of MMN "patient zero" and the first scientific publication that led to the recognition of MMN by the medical community. Multifocal motor neuropathy is nowadays recognized as a disease that produces asymmetric muscle weakness and cramping, with spontaneous motor unit activity (fasciculations and myokymia) but without sensory disorder. Read More

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A Common Kinetic Property of Mutations Linked to Episodic Ataxia Type 1 Studied in the Shaker Kv Channel.

Int J Mol Sci 2020 Oct 14;21(20). Epub 2020 Oct 14.

Department of Physics, Université de Montréal, Montréal, QC H3C 3J7, Canada.

(1) Background: Episodic ataxia type 1 is caused by mutations in the gene encoding for the voltage-gated potassium channel Kv1.1. There have been many mutations in Kv1. Read More

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October 2020

Anti-CASPR2-Antibody-Positive Isaacs' Syndrome Presenting with Myokymia, Neuropathic Pain, and Hyperhidrosis.

J Clin Neurol 2020 Oct;16(4):699-701

Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

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October 2020

Paroxysmal Symptoms in Multiple Sclerosis-A Review of the Literature.

J Clin Med 2020 Sep 25;9(10). Epub 2020 Sep 25.

Gilbert and Rose Mary Chagoury School of Medicine, Lebanese American University, Byblos 4504, Lebanon.

Paroxysmal symptoms are well-recognized manifestations of multiple sclerosis (MS). These are characterized by multiple, brief, sudden onset, and stereotyped episodes. They manifest as motor, sensory, visual, brainstem, and autonomic symptoms. Read More

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September 2020

An ultrasonographic and electromyographic evaluation of jumping stump possibly due to a neuroma in a patient with transradial amputation: A case report.

J Back Musculoskelet Rehabil 2021 ;34(1):33-37

Department of Physical Medicine and Rehabilitation, Marmara University School of Medicine, Istanbul, Turkey.

Background And Objective: Jumping stump is an uncommon movement disorder characterized by involuntary movements and severe neuropathic pain in the stump. The pathophysiology and etiology of this phenomenon have not yet been clearly elucidated, and unfortunately, no proven treatment with successful recovery exists. This report aims to describe a severe painful jumping stump, possibly due to neuromas, in a traumatic transradial amputee. Read More

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How can neurophysiological studies help with movement disorders characterization in clinical practice? A review.

Arq Neuropsiquiatr 2020 05 29;78(8):512-522. Epub 2020 May 29.

Universidade Federal de Minas Gerais, Departamento de Clínica Médica, Unidade de Distúrbios do Movimento, Belo Horizonte MG, Brazil.

Background: Neurophysiological studies are ancillary tools to better understand the features and nature of movement disorders. Electromyography (EMG), together with electroencephalography (EEG) and accelerometer, can be used to evaluate a hypo and hyperkinetic spectrum of movements. Specific techniques can be applied to better characterize the phenomenology, help distinguish functional from organic origin and assess the most probable site of the movement generator in the nervous system. Read More

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One Bite, Two Patients: Disparate Clinical Courses Following Simultaneous Crotalus oreganus abyssus Envenomation.

Wilderness Environ Med 2020 Sep 18;31(3):354-357. Epub 2020 Aug 18.

Division of Medical Toxicology and Precision Medicine, Department of Medicine, University of Arizona College of Medicine, Phoenix, AZ; Department of Medical Toxicology, Banner - University Medicine Center Phoenix, Phoenix, AZ.

A number of crotaline species have been associated with neurotoxic envenomation in North America. One clinical sign that can occur is myokymia: fine, involuntary, wave-like muscle movements occurring at regular intervals. We report an unusual scenario in which a single snakebite resulted in simultaneous envenomation of 2 patients. Read More

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September 2020

Marcus Gunn Jaw-Winking Synkinesis With Ipsilateral Eyelid Myokymia.

Ophthalmic Plast Reconstr Surg 2020 Nov/Dec;36(6):566-568

Department of Ophthalmology Cleveland Clinic Lerner College of Medicine of Case Western University Cleveland, Ohio, U.S.A.

Purpose: To describe a novel observation of ipsilateral eyelid myokymia in the context of Marcus Gunn jaw-winking synkinesis (MGJWS).

Methods: A retrospective case series of 5 patients observed to have myokymia in the context of MGJWS in 2 tertiary hospitals in Riyadh, Saudi Arabia was conducted. Demographic profile including age and gender, and clinical features were analyzed. Read More

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William F. Hoyt and the Neuro-Ophthalmology of Superior Oblique Myokymia and Ocular Neuromyotonia.

J Neuroophthalmol 2020 Sep;40 Suppl 1:S29-S34

Department of Ophthalmology, University of California San Francisco, San Francisco, California.

The contributions of William F. Hoyt, MD, to the field of neuro-ophthalmology are immense. His precision in history-taking and examination skills provided the foundation to fully understand a clinical disorder-determining its underlying pathophysiology, prognosis, and management. Read More

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September 2020

Superior Oblique Myokymia Presumed Due to Large Posterior Fossa Arteriovenous Malformation.

Can J Neurol Sci 2020 11 5;47(6):824-825. Epub 2020 Aug 5.

Department of Surgery, Division of Ophthalmology, Hamilton Regional Eye Institute, McMaster University, Hamilton, Ontario, Canada.

A 26-year-old female presented with a complaint of intermittent oscillopsia and binocular vertical diplopia for the past 5 years. Over the past several months, she had noticed intermittent pulsatile tinnitus. She was otherwise healthy with no previous history of trauma and had no other visual or neurologic complaints. Read More

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November 2020

Functional consequences of SLC1A3 mutations associated with episodic ataxia 6.

Hum Mutat 2020 11 9;41(11):1892-1905. Epub 2020 Sep 9.

Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1) Forschungszentrum Jülich, Jülich, Germany.

The episodic ataxias (EA) are a group of inherited neurological diseases characterized by paroxysmal cerebellar incoordination. There exist nine forms of episodic ataxia with distinct neurological symptoms and genetic origins. Episodic ataxia type 6 (EA6) differs from other EA forms in long attack duration, epilepsy and absent myokymia, nystagmus, and tinnitus. Read More

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November 2020

Two novel KCNA1 variants identified in two unrelated Chinese families affected by episodic ataxia type 1 and neurodevelopmental disorders.

Mol Genet Genomic Med 2020 10 23;8(10):e1434. Epub 2020 Jul 23.

Dongguan Maternal and Child Health Care Hospital, Dongguan, China.

Background: Pathogenic KCNA1 variants have been linked to episodic ataxia type 1 (EA1), a rare neurological syndrome characterized by continuous myokymia and attacks of generalized ataxia that can be triggered by fever, abrupt movements, emotional stress, and fatigue. Currently, over 40 KCNA1 variants have been identified in individuals with EA1.

Methods: A male patient displayed partial seizures in addition to EA1 symptoms, often triggered by fever. Read More

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October 2020

Anti-CASPR2 clinical phenotypes correlate with HLA and immunological features.

J Neurol Neurosurg Psychiatry 2020 10 10;91(10):1076-1084. Epub 2020 Jul 10.

French National Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hôpital Neurologique, Hospices Civils de Lyon, Bron, France

Objective: Antibodies against contactin-associated protein-like 2 (CASPR2-Abs) have been described in acquired neuromyotonia, limbic encephalitis (LE) and Morvan syndrome (MoS). However, it is unknown whether these constitute one sole spectrum of diseases with the same immunopathogenesis or three distinct entities with different mechanisms.

Methods: A cluster analysis of neurological symptoms was performed in a retrospective cohort of 56 CASPR2-Abs patients. Read More

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October 2020

Facial spasms.

Dis Mon 2020 Oct 1;66(10):101041. Epub 2020 Jul 1.

Department of Ophthalmology and Visual Science, University of Chicago, Chicago, IL, United States; Division of Ophthalmology, NorthShore University HealthSystem, Evanston, IL, United States. Electronic address:

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October 2020