Project description:Although involuntary movements of stumps are less frequent than phantom sensation or other neurological sequelae of limb amputation, they represent a phenomenon that has been known for many years. The pathophysiology remains unknown, but it seems to be related to damage to the peripheral nervous system. Treatment is not standardized, but antimyoclonic drugs seem to be useful.
Project description:Choreoathetoid movements are quite common in cerebral palsy (CP). This is the first report of a patient with choreoathetoid CP who was successfully treated with carbamazepine. Therefore, clinicians should try carbamazepine for involuntary movements in CP patients before pursuing other procudures.
Project description:Acquired periodic alternating nystagmus (PAN) describes a horizontal jerk nystagmus that reverses its direction with a predictable cycle, and is thought to arise from lesions involving the brainstem and cerebellum. We report a 20-year-old patient with PAN who presented with an acute vertiginous episode and developed an involuntary head movement that initially masked the PAN. The involuntary head movements were abolished with a subtherapeutic dose of botulinum toxin to the neck muscles. We propose that the head movements initially developed as a compensatory movement to the nystagmus, to maintain visual fixation in the presence of the underlying nystagmus, and became an entrained involuntary behavior. This case highlights the importance of disambiguating psychogenic from organic pathology as this may have clinical therapeutic implications, in this case resolution of the most disabling symptom which was her head oscillations, leading to improved day-to-day function despite PAN.
Project description:Long-term dopamine replacement therapy in Parkinson's disease leads to the development of disabling involuntary movements named dyskinesias that are related to adaptive changes in striatal signaling pathways. The chronic transcription factor DeltaFosB, which is overexpressed in striatal neurons after chronic dopaminergic drug exposure, is suspected to mediate these adaptive changes. Here, we sought to demonstrate the ability of DeltaFosB to lead directly to the abnormal motor responses associated with chronic dopaminergic therapy. Using rAAV (recombinant adenoassociated virus) viral vectors, high levels of DeltaFosB expression were induced in the striatum of dopamine-denervated rats naive of chronic drug administration. Transgenic DeltaFosB overexpression reproduced the entire spectrum of altered motor behaviors in response to acute levodopa tests, including different types of abnormal involuntary movements and hypersensitivity of rotational responses that are typically associated with chronic levodopa treatment. JunD, the usual protein partner of DeltaFosB binding to AP-1 (activator protein-1) sites of genes, remained unchanged in rats with high DeltaFosB expression induced by viral vectors. These findings demonstrate that the increase of striatal DeltaFosB in the evolution of chronically treated Parkinson's disease may be a trigger for the development of abnormal responsiveness to dopamine and the emergence of involuntary movements.
Project description:BackgroundThere have been anecdotal reports of episodic involuntary movements in the Border Terrier dog breed for over a decade. Recently, it has been hypothesized that this condition may be a form of paroxysmal dystonic choreoathetosis. The aim of this study was to characterize the phenomenology and clinical course of this condition and compare it to known human movement disorders.MethodsData were collected retrospectively from clinical cases treated by veterinary neurologists and additional information was collected prospectively with an ad-hoc online survey directed to owners of affected dogs.ResultsThe episodes are characterized by generalized dystonia, tremors, titubation, and, in some cases, autonomic signs, such as salivation and vomiting. The median age at onset of the episodes was 3 years and the interval between clusters of episodes could last several months. Most of the episodes occurred from rest, and 67% of the owners reported that the episodes were associated with a trigger, most often excitement. Some owners reported an improvement after changing their dog's diet. We hypothesize that the Border Terrier attacks represent a form of paroxysmal nonkinesigenic dyskinesia.ConclusionsThe finding of a dystonia phenotype within an inbred population suggests a genetic predisposition, and elucidating the genetic cause could facilitate improved understanding of dystonia. This genetic predisposition and the effect of treatment with anticonvulsant drugs and dietary changes on the severity of the paroxysms warrant further investigation on this condition.
Project description:Hydroxychloroquine (HCQ) has been used as an investigational drug for patients with moderate to severe coronavirus disease 2019 (COVID-19). There have been concerns of potential harms from side effects of the drug. We present a case of a 38-year-old male who was started on HCQ for COVID-19 pneumonia. He was referred for evaluation of myoclonus of all extremities, which resolved after discontinuation of HCQ. The involuntary movements were first reported after the initiation of HCQ, persisted despite improvement in inflammatory and radiologic parameters and eventually resolved after HCQ discontinuation. This supports a possible causality related to adverse drug reactions from HCQ that have not been commonly reported.
Project description:Involuntary eye movements during fixation of gaze are typically transiently inhibited following stimulus onset. This oculomotor inhibition (OMI), which includes microsaccades and spontaneous eye blinks, is modulated by stimulus saliency and anticipation, but it is currently unknown whether it is sensitive to familiarity. To investigate this, we measured the OMI while observers passively viewed a slideshow of one familiar and 7 unfamiliar facial images presented briefly at 1 Hz in random order. Since the initial experiments indicated that OMI was occasionally insensitive to familiarity when the facial images were highly visible, and to prevent top-down strategies and potential biases, we limited visibility by backward masking making the faces barely visible or at the fringe of awareness. Under these conditions, we found prolonged inhibition of both microsaccades and eye-blinks, as well as earlier onset of microsaccade inhibition with familiarity. These findings demonstrate, for the first time, the sensitivity of OMI to familiarity. Because this is based on involuntary eye movements and can be measured on the fringe of awareness and in passive viewing, our results provide direct evidence that OMI can be used as a novel physiological measure for studying hidden memories with potential implications for health, legal, and security purposes.
Project description:New onset refractory status epilepticus (NORSE) is a neurological emergency and difficult to treat condition. We report a case of involuntary movements resulting from thiopentone sodium infusion during the management of refractory status epilepticus. A young woman was admitted with fever and NORSE in the neurology intensive care unit. In addition to supportive measures, she was treated with intravenous lorazepam, phenytoin sodium, sodium valproate, midazolam and thiopentone sodium. While on thiopentone sodium, she developed involuntary twitches involving her upper limbs and face with EEG showing no evidence of ongoing status epilepticus. Because of the temporal relationship with thiopentone infusion, we tapered the dose of thiopentone sodium, which resulted in the disappearance of the movements. The patient recovered well with no recurrence of the seizures during the hospital stay.
Project description:Myoclonus is a sudden brief, involuntary muscle jerk. Of all the movement disorders, myoclonus is the most difficult to encapsulate into any simple framework. On the one hand, a classification system is required that is clinically useful to aid in guiding diagnosis and treatment. On the other hand, there is need for a system that organizes current knowledge regarding biological mechanisms to guide scientific research. These 2 needs are distinct, making it challenging to develop a robust classification system suitable for all purposes. We attempt to classify myoclonus as "epileptic" and "nonepileptic" based on its association with epileptic seizures. Myotonia in people may be divided into 2 clinically and molecularly defined forms: (1) nondystrophic myotonias and (2) myotonic dystrophies. The former are a group of skeletal muscle channelopathies characterized by delayed skeletal muscle relaxation. Many distinct clinical phenotypes are recognized in people, the majority relating to mutations in skeletal muscle voltage-gated chloride (CLCN1) and sodium channel (SCN4A) genes. In dogs, myotonia is associated with mutations in CLCN1. The myotonic dystrophies are considered a multisystem clinical syndrome in people encompassing 2 clinically and molecularly defined forms designated myotonic dystrophy types 1 and 2. No mutation has been linked to veterinary muscular dystrophies. We detail veterinary examples of myotonia and attempt classification according to guidelines used in humans. This more precise categorization of myoclonus and myotonia aims to promote the search for molecular markers contributing to the phenotypic spectrum of disease. Our work aimed to assist recognition for these 2 enigmatic conditions.