Search

Lance-Adams syndrome (LAS) was first described in 1963 by Lance and Adams, who cited four cases of posthypoxic action myoclonus. Since then, less than 150 cases have been reported world-wide. LAS differs from acute posthypoxic myoclonus, which usually occurs within twelve hours of the anoxic event, with the patient remaining in a deep coma with an extremely poor prognosis. Patients with LAS retain neurological function and develop myoclonus days or weeks after their hypoxic event. This report describes the case of a 64-year-old male who developed LAS following cardiac arrest. His progression from ICU to outpatient was followed through multiple electroencephalograms.

Objective To investigate the mechanisms by which Perampanel (PER) reduces the severity of action myoclonus, we studied on MEG signals the changes occurring in cortico-muscular coherence (CMC) and cortico-cortical connectivity in patients with progressive myoclonus epilepsies. Methods The subjects performed an isometric extension of the hand; CMC and cortico-cortical connectivity were assessed using autoregressive models and generalized partial-directed coherence. The contralateral (Co) sensors showing average CMC values >0.7 of the maximum (set to 1) were grouped as central (C) regions of interest (ROI), while adjacent sensors showing CMC values >0.3 were grouped as Surrounding (Sr) ROIs. Results Under PER treatment, CMC decreased on Co C and Sr ROIs, but also on homologous ipsilateral (Ip) ROIs; out-degrees and betweenness centrality increased in Co ROIs and decreased in Ip ROIs. The flow from Ip to Co ROIs and from activated muscles to Ip C ROI decreased. Conclusion The improvement of myoclonus corresponded to decreased CMC and recovered leadership of the cortical regions directly involved in the motor task, with a reduced interference of ipsilateral areas. Significance Our study highlights on mechanisms suitable to treating myoclonus and suggests the role of a reduced local synchronization together a better control of distant synaptic effects.

Movement disorder, although rare, is increasingly being recognized as the initial presenting sign of the hyperglycemic state. Although chorea-ballism has frequently been reported among diabetics, monoballism is a very rare phenomenon. While myoclonus is common, diaphragmatic myoclonus is extremely rare. Moreover, diaphragmatic myoclonus as the initial presenting manifestation has never been reported before. Herein, we report an index case of a 62-year-old previously undiagnosed diabetic lady presented with acute onset constellation of multiple abnormal movements viz. monoballism, focal myoclonus, action myoclonus, and diaphragmatic myoclonus. All of them disappeared with achieving normoglycemia. This case underscores the importance of rapid capillary blood glucose testing in any patient presenting with acute onset abnormal movements. This approach can especially be rewarding as it helps in the rapid diagnosis of a reversible catastrophe and avoiding unnecessary costly investigations.

Background: Post-hypoxic myoclonus (PHM) is characterized by generalized myoclonus after hypoxic brain injury. Myoclonus is often functionally impairing and refractory to medical therapies. Deep brain stimulation (DBS) has been used to treat myoclonus-dystonia, but few cases of PHM have been described. Case report: A 33-year-old woman developed severe, refractory generalized myoclonus after cardiopulmonary arrest from drowning. We performed MRI-guided asleep bilateral pallidal DBS placement, resulting in improvement in action myoclonus at one year. Discussion: Our case contributes to growing evidence for DBS for PHM. Interventional MRI guided DBS technique can be used for safe and accurate lead placement. Highlights: We report a case of a patient who developed post-hypoxic myoclonus after cardiopulmonary arrest from drowning, who later underwent deep brain stimulation to treat refractory myoclonus. This is the first case to describe asleep, interventional MRI-guided technique for implanting DBS leads in post-hypoxic myoclonus.

Background Kufor-Rakeb syndrome (KRS) is a rare autosomal recessive neurologic disease with diverse phenotypic features. Herein we report an Iranian KRS family with seizure and action myoclonus in addition to other typical manifestations of this syndrome. Method All family members underwent careful neurologic examination. Exome sequencing was performed and ATP13A2 variation genotyped in all family members. Results Cognitive deficits, hypokinesia, rigidity, spasticity, brisk deep tendon reflexes, upward gaze palsy, tremor, and facial-faucial-finger mini-myoclonus were the common manifestations of all affected siblings. Two cases had seizure and the most severely affected sibling demonstrated severe action myoclonus. Exome sequencing identified a homozygous nonsense mutation c.2455C>T;p.Arg819* in ATP13A2 gene. Conclusions We reported five KRS affected siblings who manifested myoclonus and seizure. The most severely affected one demonstrated action myoclonus, which has not been reported so far.

A case of severe action myoclonus after pulmonary arrest is described. Although there was benefit from oral pharmacotherapy, action myoclonus remained disabling. A favorable response to baclofen during an intrathecal trial led to eventual placement of an intrathecal baclofen pump. The present case illustrates the potential utility of intrathecal baclofen for treating this condition. Level of Evidence V

Objectives: Chronic post-hypoxic myoclonus, known as Lance-Adams syndrome (LAS), is a rare complication of successful cardiopulmonary resuscitation. It is characterized by intention myoclonus, cerebellar ataxia, and preserved intellect. The basis of the disease and its long-term prognosis remain unclear. Case report: The authors present a 53-year-old woman with a history of asthma bronchiale who suffered from myoclonus after hypoxic brain damage due to cardiac arrest. Advanced electrophysiological (quantitative EEG) and MR (MR spectroscopy) techniques were employed. Conclusions: Over long-term observation the results suggested permanent synaptic rearrangements of the neuronal networks due to brain plasticity in the patient after the brain hypoxia.

A 62-year-old man was resuscitated after an in-hospital pulseless electrical activity (PEA) cardiac arrest. He awakened after 24 hours but after another 24-hour interval, he had worsening action and stimulus-induced myoclonus.[1–3][1] He was able to relax fully without movement but any

Predicting the neurological outcome in survivors of cardiorespiratory arrest is difficult. A distinction has been made between acute and chronic posthypoxic myoclonus, called myoclonic status epilepticus and Lance–Adams syndrome (LAS), respectively, with the acute condition carrying a bad prognosis. Here, we report a case of a 37-year-old female who developed seizures after a successful cardiopulmonary resuscitation. The available literature on such cases is very rare and has generally mentioned a poor outcome. However, our patient was successfully managed and showed clinical features of LAS. Thus, making an early diagnosis and proper management of hypoxic brain insults is positively related to improving the patient's functional outcome.

Objective The objective of this study was to explore the short-term effects of repetitive transcranial magnetic stimulation (rTMS) on action myoclonus. Methods Nine patients with Unverricht–Lundborg (EPM1) progressive myoclonus epilepsy type underwent two series of 500 stimuli at 0.3 Hz through round coil twice a day for five consecutive days. Clinical and neurophysiological examinations were performed two hours before starting the first rTMS session and two hours after the end of the last rTMS session. Results Eight patients completed the protocol; one discontinued because of a transient increase in spontaneous jerks. The unified myoclonus rating scale indicated a 25% reduction in posttreatment myoclonus with action score associated with an increase in the cortical motor threshold and lengthening of the cortical silent period (CSP). The decrease in the myoclonus with action scores correlated with the prolongation of CSP. Conclusions Repetitive transcranial magnetic stimulation can be safely used in patients with EPM1, improves action myoclonus, and partially restores deficient cortical inhibition.

Background To explore the cortical network sustaining action myoclonus and to found markers of the resulting functional impairment, we evaluated the distribution of the cortico-muscular coherence (CMC) and the frequency of coherent cortical oscillations with magnetoencephalography (MEG). All patients had EPM1 (Unverricht-Lundborg) disease known to present with prominent and disabling movement-activated myoclonus. Methods Using autoregressive models, we evaluated CMC on MEG sensors grouped in regions of interests (ROIs) above the main cortical areas. The movement was a repeated sustained isometric extension of the right hand and right foot. We compared the data obtained in 10 EPM1 patients with those obtained in 10 age-matched controls. Results As expected, CMC in beta band was significantly higher in EPM1 patients compared to controls in the ROIs exploring the sensorimotor cortex, but, it was also significantly higher in adjacent ROIs ipsilateral and contralateral to the activated limb. Moreover, the beta-CMC peak occurred at frequencies significantly slower and more stable frequencies in EPM1 patients with respect to controls. The frequency of the beta-CMC peak inversely correlated with the severity of myoclonus. Conclusions the high and spatially extended beta-CMC peaking in a restricted range of low-beta frequencies in EPM1 patients, suggest that action myoclonus may result not only from an enhanced local synchronization but also from a specific oscillatory activity involving an expanded neuronal pool. The significant relationship between beta-CMC peak frequency and the severity of the motor impairment can represent a useful neurophysiological marker for the patients’ evaluation and follow-up.

Background: Myoclonus-dystonia (M-D) is genetic and clinically heterogeneous. Identification and description of rare M-D syndromes may contribute to gene identification. Results: Here, we describe a new, autosomal dominant M-D syndrome in a 3-generation pedigree showing anticipation. Patients have progressive action-induced multifocal dystonia and generalized myoclonus. A remarkable feature of the syndrome is action myoclonus in the lower extremities triggered by upright posture, causing instability. Electrophysiological characterization shows a 12-Hz peak in the EMG autospectrum and corticomuscular and intermuscular coherences. Conclusions: A new familial M-D syndrome with progressive action myoclonus and dystonia is described. (C) 2011 Movement Disorder Society

Introduction. Chronic post-anoxic myoclonus, also known as Lance-Adams syndrome, may develop following hypoxic brain injury, and is resistant to pharmacological therapy. Case report. The patient we presented developed post-anoxic action myoclonus with severe, completely incapacitating myoclonic jerks. Myoclonus did not respond to the treatment with commonly used agents, i.e. valproate and clonazepam alone or in combination. Improvement of the action myoclonus was observed only after adding levetiracetam. Conclusion. Although Lance-Adams syndrome may not be fully curable at this point, levetiracetam appears to be a promising agent that can significantly improve functional level and overall quality of life of patients with this disorder.

Editors' Note: Critiquing “Orthostatic myoclonus associated with Caspr2 antibodies,” van Gerpen et al. disagree with the diagnosis of orthostatic myoclonus (OM), which, according to their experience, clinically manifests as low-amplitude, tremulous movements, restricted to the legs during standing; appears as semirhythmic bursts lasting less than 50 milliseconds on surface EMG; and lacks prominent action myoclonus in the legs. Govert et al., authors of the case report, defend their diagnosis and explain that OM can be present in the arms and can have subtle action myoclonus. In reference to “Antibiotic-associated encephalopathy,” Dr. Stip argues that there is no clear evidence to link macrolides to altered dopamine levels or NMDA receptor activity and that macrolides have poor CSF …

Lance-Adams syndrome (LAS) is a rare complication of successful cardiopulmonary resuscitation and is often accompanied by action myoclonus. LAS is seen in patients who have undergone a cardiorespiratory arrest, later regained consciousness, and then developed myoclonus days or weeks after the event. Less than 150 cases of LAS have been reported in the worldwide medical literature. Here, we present a 32-year-old man who suffered from myoclonus after hypoxic brain damage due to hanging himself. This case was diagnosed as Lance-Adams syndrome according to a history of hypoxic brain damage, the clinical features, and the neuroimages such as brain SPECT. Making an early diagnosis and properly managing LAS is positively related to improving the patient's functional outcome. If patients have posthypoxic myoclonus after successful cardiopulmonary resuscitation, we should consider the diagnosis of LAS and initiate a proper rehabilitation program.

Background: Perinatal anoxia rarely causes myoclonus as the main neurologic abnormality. The exact neuronal mechanism underlying myoclonus induced by perinatal anoxia remains unknown. Some studies have indicated that the development of involuntary movements may be related to the maturation of the thalamus after birth. Objectives and Methods: Here, we describe the first case of a patient who developed action myoclonus after experiencing perinatal anoxia and was successfully treated by chronic deep brain stimulation (DBS) of the thalamus (thalamic DBS). Results andConclusion: The effectiveness of chronic thalamic DBS in this patient supports the concept of involvement of the thalamus in postperinatal anoxic myoclonus.

Three patients who were hospitalized due to cerebrovascular incident with different lesions localization presented with ipsilateral epileptic syndromes with action myoclonus of the hands and in one case associated with active myoclonus of the same half of the face. The aim was to prove the existence of a direct correlation between cerebrovascular incident as the cause and developed action myoclonus as a result of cerebral lesions by analysing the pathophysiological basis of this entity. The analysed results were obtained through laboratory, serial electroencephalograph monitoring, CD-MAV, computerized tomography or magnetic resonance imaging of the brain and magnetic resonance angiography of blood vessels of the brain. Based on results, the base for the introduction of anticonvulsant therapy, which completely suppressed the clinical picture, was set. This supports the direct relation between cerebrovascular lesions as pathoanatomic substrate and action myoclonus as a pathophysiological substrate. The mechanism of myoclonus as a result of cerebrovascular disease is largely unknown. The essence of the discussion is based on the possible pathophysiological mechanisms of secondary myoclonus. Further analysis should give a deeper insight into the damage mechanisms, but also the survival of neurons that can help and lead to new ways of treating cerebrovascular disease.

Posthypoxic and postencephalitic myoclonus is often poorly controlled with current treatments. The authors successfully treated three patients with posthypoxic and postencephalitic myoclonus by using levetiracetam, a new antiepileptic drug. Levetiracetam appears to be a promising agent for treating action myoclonus caused by hypoxic and encephalitic brain injury-the degree of functional improvement may depend on the severity of associated motor dysfunction.

Acetazolamide treatment significantly improves action myoclonus in Ramsay Hunt Syndrome. A family with two brothers and a sister, and a sporadic case with Ramsay Hunt Syndrome and uncontrollable action myoclonus, are described where addition of oral acetazolamide lead to marked improvement in their action myoclonus.

Article abstract-Posthypoxic and postencephalitic myoclonus is often poorly controlled with current treatments. The authors successfully treated three patients with posthypoxic and postencephalitic myoclonus by using levetiracetam, a new antiepileptic drug. Levetiracetam appears to be a promising agent for treating action myoclonus caused by hypoxic and encephalitic brain injury-the degree of functional improvement may depend on the severity of associated motor dysfunction.

Report of a 48-year-old patient presenting the syndrome of action myoclonus as described by Lance and Adams, during an acute renal decompensation. The action myoclonus appeared in the stage of acute metabolic acidosis and hyperosmolarity, and proved completely reversible. Action myoclonus has not before been reported as a symptom of metabolic disorder. It's prognosis in such a context seems much better than in post-anoxic cases in whom it always has proved persistent. The only sequel in our patient was a mild pyramidal and cerebellar syndrome confirming the statement of Lance and Adams that mild cerebellar ataxia is part of the action myoclonus syndrome.

Two vermisectomized photosensitive baboons exhibited two different types of myoclonus, one induced by intermittent light stimulation (ILS) and the other occuring "spontaneously". The characteristics of these two types of myoclonus are described from a clinical and from an ECoG point of view. Myoclonus induced by ILS (ML) started at the eyelids and secondarily invaded the face and body; it was always preceded by frontorolandic spike-waves or polyspike-waves. The "spontaneous" myoclonus which followed vermisectomy (MV) was "massive", but involved firstly the trunk and secondarily the face and limbs; no ECoG paraoxysm accompanied this myoclonus, but we observed a parietal evoked potential of small amplitude, 10--15 msec after its onset. If MLs can be considered as consequences of the fronto-rolandic paroxysmal discharges, MVs seem to originate in the brain stem but appear similar to action myoclonus. This experimental situation showing two types of myoclonus resembles human hereditary degenerative syndromes (dyssynergic cerebellar myoclonus, progressive myoclonic epilepsy), without being exactly comparable. The conditions in which MVs were seen and their modifications during sleep and by different drugs are described. The relationships between MVs and MLs and myoclonic epilepsy are discussed.

Clinical electrophysiological and neuroradiological examination of a case of unilateral intention and action myoclonus is reported. Brachial arteriography revealed an angioma located mainly in the lateral portion of the right posterior thalamus. Clinical and electrophysiological findings suggesting involvement of nonthalamic structures were absent. Our case, together with some cases previously described, raises the possibility that volitional myoclonus may be related to a relatively circumscribed damage of some diencephalic and/or mesencephalic structures. The rare occurrence of a hyperkinetic syndrome as principal symptom of a cerebral vascular malformation should be borne in mind in view of the potential risk of a stereotactic surgical procedure designated to alleviate the involuntary movements.

Description of a patient with Huntington's chorea of adult onset who subsequently developed an action myoclonus.

• A patient with postanoxic action myoclonus (Lance-Adams syndrome) was severely disabled with this movement disorder. Valproate sodium was administered orally, with complete resolution of the myoclonus. This favorable response has been maintained for two years. Excessive yawning, the only side effect encountered, was dose related and was abolished with the addition of pimozide to the drug regimen.

SummaryClinical and pathological findings in two cases of degenerative progressive myoclonic epilepsy (PME) are described. The clinically difficult task of differentiating a “cerebellar” tremor from an action myoclonus is emphasized. Simultaneous elect roencephalography and electrokymography was done, using capacity to ground transients for recording hand movements. This method was found useful in corroborating the cerebellar nature of the remaining disorder, after successful treatment of the myoclonic element with anticonvulsants.

Five patients with relatively mild but disabling action myoclonus displayed a subtle and heretofore unemphasized electroencephalographic manifestation of action myoclonus consisting of low-voltage, central fast activity somatotopically related to the extremity being used. The importance of recognizing this rhythm lies in its association with milder forms of action myoclonus which resemble other types of movement disorders, the difficulty in recognizing this rhythm unless special tests are carried out, and the beneficial response of anticonvulsant therapy if the nature of the movement is realized.

This review covers recent advances in a variety of dyskinesias. Introduction of new drugs for the treatment of myoclonus and sensory biofeedback therapy for focal dystonia are expanding our concepts of these types of movement disorders. Progress in the treatment of action myoclonus is especially noteworthy and has led to the impli cation of serotonin deficit in the pathophysiology of this syndrome. Knowledge of the biochemical pathology of Huntington’s chorea has outpaced therapy for this disorder, but new forms of therapy have been proposed based on the chemical findings. Basic pharmacologic studies suggest pathophysiologic mechanisms for the syndrome known as tardive dyskinesia, but treatment is still far from ideal for this disorder. Other movement disorders with recent therapeutic advances include essential tremor and hemiballism

The syndrome of intention and action myoclonus has been described by Lance and Adams (1963) as a sequel of acute anoxic encephalopathy. In their first publication (1971a), the authors have reported dramatic effects of 5HTP on that syndrome, confirmed since then by other investigators; they expose in this paper the therapeutic protocol used and their experience of treatment of six patients with association 5HTP and a peripheric inhibitor of monoamines decarboxylase. A brief review of literature is presented with references.

A case of atypical progressive supranuclear palsy is presented that differs from the classical description of the disorder. The patient was a 50 year old woman who had a neurologic disturbance that progressed over eight years and that was studied clinically and pathologically. The case differs from classical progressive supranuclear palsy in that action myoclonus, seizures, and a late eye-movement disorder were present, while rigidity and dementia were relatively absent. An additional difference is that the most prominent pathologic findings were in the midbrain, dentate nuclei, and cerebral cortex. If the case is properly classified, it is unique in its clinical presentation and in the distribution of lesions.

Bruton type agammaglobulinemia is an X-linked disease with humoral immunological deficiency. Children with congenital agammaglobulinemia develop bacterial infections easily. We describe a 15-year-old

To the Editor.— We recently had a patient who had postanoxic action myoclonus (Lance-Adams syndrome). This severe movement disorder was completely suppressed with the oral administration of valproate sodium (Epilim [Britain]; Depakene, comparable US product) at a dosage of 1,000 mg daily, with corresponding serum levels of 50 to 80 μg/mL. At these serum levels and while receiving no other therapy, severe uncontrollable yawning developed. This was occurring every two to three minutes. Lowering the dosage of the valproate sodium abolished the yawning, and its reinstitution at the previous level led to its return. Pimozide (Orap), 400 mg daily, was added to the regimen of full dosage of valproate sodium, and the yawning disappeared within one day. Withdrawal of the pimozide caused the yawning to reappear. Computerized tomography of the brain demonstrated mild generalized cortical atrophy with an area of infarction in the left inferior temporal lobe. Serotonin deficiency was

Ten patients with severe disabling myoclonus were treated with clonazepam, sodium valproate, primidone and piracetam alone, or in different combinations. Electrophysiological assessment indicated a cortical origin for the myoclonus in every case. Considerable improvement of myoclonus was achieved with combinations of these drugs in all patients, but this was not possible with monotherapy. In one patient two drugs were necessary (clonazepam and piracetam); in the others more than two drugs were required. The combination of sodium valproate, clonazepam and primidone (3 patients), or piracetam, clonazepam and primidone (3 patients), or the four drugs together (3 patients) was necessary to provide substantial relief of myoclonus. Such polytherapy generally was tolerated well. The benefits of treatment continued for more than 1 year in all cases, although progressive underlying pathology often caused other increasing disability.

Myoclonic disorders are often disabling and difficult to treat and present a therapeutic challenge to the physician. Attempts to control myoclonic jerks have been made with several drugs, of which only clonazepam 1 and L-5-hydroxytryptophan (L-5-HTP) 2 seem to have long-term value in practice. This article reports three cases of nonepileptic myoclonus that severely interfered with normal function. One patient suffered from postanoxic action myoclonus, 3 and two patients suffered from nocturnal myoclonus. 4 Several kinds of medication had proved ineffective, but valproic acid alone produced rapid and enduring relief. REPORT OF CASES Case1.—A 52-year-old man had fungal endocarditis and septicemia develop one month after cardiac valvular replacement. The valve prosthesis was changed in a replacement. After surgery, pericardial bleeding caused cardiac tamponade and asystole one week after the replacement. Anoxic brain damage with cerebral and brainstem signs and severe action myoclonus resulted. The patient was unconscious for two

In Swiss mice, muscimol (3 mg per kilogram, intraperitoneally) caused myoclonic jerks of the hindquarters. These jerks were strong, repetitive, more or less regular, and of high frequency (peak response, 76 per minute). Pretreatment with sodium gamma-hydroxybutyrate (50 to 200 mg per kilogram) caused a dose-dependent blockade of these jerks. This drug also nullified an already developed muscimol response. All of the drugs currently being used in the management of postanoxic action myoclonus (Lance-Adams syndrome) block this response of muscimol. Gamma-hydroxybutyrate may be of value in the management of Lance-Adams syndrome and other forms of myoclonus.