Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Research on myoclonus is supported through the National Institute of Neurological Disorders and Stroke (NINDS). The primary focus of research is on the role of neurotransmitters and receptors involved in the disease. Identifying whether or not abnormalities in these pathways cause myoclonus may help in efforts to develop drug treatments and diagnostic tests. Determining the extent that genetics play in these abnormalities may lead to potential treatments for their reversal, potentially correcting the loss of inhibition while enhancing mechanisms in the body that would compensate for their effects.
The medical treatment of essential tremor at the Movement Disorders Clinic at Baylor College of Medicine begins with minimizing stress and tremorgenic drugs along with recommending a restricted intake of beverages containing caffeine as a precaution, although caffeine has not been shown to significantly intensify the presentation of essential tremor. Alcohol amounting to a blood concentration of only 0.3% has been shown to reduce the amplitude of essential tremor in two-thirds of patients; for this reason it may be used as a prophylactic treatment before events during which one would be embarrassed by the tremor presenting itself. Using alcohol regularly and/or in excess to treat tremors is highly unadvisable, as there is a purported correlation between tremor and alcoholism. Alcohol is thought to stabilize neuronal membranes via potentiation of GABA receptor-mediated chloride influx. It has been demonstrated in essential tremor animal models that the food additive 1-octanol suppresses tremors induced by harmaline, and decreases the amplitude of essential tremor for about 90 minutes.
Two of the most valuable drug treatments for essential tremor are propranolol, a beta blocker, and primidone, an anticonvulsant. Propranolol is much more effective for hand tremor than head and voice tremor. Some beta-adrenergic blockers (beta blockers) are not lipid-soluble and therefore cannot cross the blood–brain barrier (propranolol being an exception), but can still act against tremors; this indicates that this drug’s mechanism of therapy may be influenced by peripheral beta-adrenergic receptors. Primidone’s mechanism of tremor prevention has been shown significantly in controlled clinical studies. The benzodiazepine drugs such as diazepam and barbiturates have been shown to reduce presentation of several types of tremor, including the essential variety. Controlled clinical trials of gabapentin yielded mixed results in efficacy against essential tremor while topiramate was shown to be effective in a larger double-blind controlled study, resulting in both lower Fahn-Tolosa-Marin tremor scale ratings and better function and disability as compared to placebo.
It has been shown in two double-blind controlled studies that injection of botulinum toxin into muscles used to produce oscillatory movements of essential tremors, such as forearm, wrist and finger flexors, may decrease the amplitude of hand tremor for approximately three months and that injections of the toxin may reduce essential tremor presenting in the head and voice. The toxin also may help tremor causing difficulty in writing, although properly adapted writing devices may be more efficient. Due to high incidence of side effects, use of botulinum toxin has only received a C level of support from the scientific community.
Deep brain stimulation toward the ventral intermediate nucleus of the thalamus and potentially the subthalamic nucleus and caudal zona incerta nucleus have been shown to reduce tremor in numerous studies. That toward the ventral intermediate nucleus of the thalamus has been shown to reduce contralateral and some ipsilateral tremor along with tremors of the cerebellar outflow, head, resting state and those related to hand tasks; however, the treatment has been shown to induce difficulty articulating thoughts (dysarthria), and loss of coordination and balance in long-term studies. Motor cortex stimulation is another option shown to be viable in numerous clinical trials.
Concerning more serious afflictions, the complex origins of myoclonus may be treated with multiple drugs, which have a limited effect individually, but greater when combined with others that act on different brain pathways or mechanisms. Treatment is most effective when the underlying cause is known, and can be treated as such. Some drugs being studied in different combinations include clonazepam, sodium valproate, piracetam, and primidone. Hormonal therapy may improve responses to antimyoclonic drugs in some people.
Some studies have shown that doses of 5-hydroxytryptophan (5-HTP) leads to improvement in patients with some types of action myoclonus and PME. These differences in the effect of 5-HTP on patients with myoclonus have not yet been explained.
Many of the drugs used for myoclonus, such as barbiturates, phenytoin and primidone, are also used to treat epilepsy. Barbiturates slow down the central nervous system and cause tranquilizing or antiseizure effects. Phenytoin and primidone are effective antiepileptics drugs, although phenytoin can cause liver failure or have other harmful long-term effects in patients with PME. Sodium valproate is an alternative therapy for myoclonus and can be used either alone or in combination with clonazepam. Some people have adverse reactions to clonazepam and/or sodium valproate.
When patients are taking multiple medications, the discontinuation of drugs suspected of causing myoclonus and treatment of metabolic derangements may resolve some cases of myoclonus. When pharmacological treatment is indicated anticonvulsants are the main line of treatment. Paradoxical reactions to treatment are notable. Drugs which most people respond to may in other individuals worsen their symptoms. Sometimes this leads to the mistake of increasing the dose, rather than decreasing or stopping the drug. Treatment of myoclonus focuses on medications that may help reduce symptoms. Drugs used include sodium valproate, clonazepam, the anticonvulsant levetiracetam, and piracetam. Dosages of clonazepam usually are increased gradually until the patient improves or side effects become harmful. Drowsiness and loss of coordination are common side effects. The beneficial effects of clonazepam may diminish over time if the patient develops a tolerance to the drug.
In forms of myoclonus where only a single area is affected, and even in a few other various forms, Botox injections (OnabotulinumtoxinA) may be helpful. The chemical messenger responsible for triggering the involuntary muscle contractions is blocked by the Botulinum toxins of the Botox.
Surgery is also a viable option for treatment if the symptoms are caused by a tumor or lesion in the brain or spinal cord. Surgery may also correct symptoms in those where myoclonus affects parts of the face or ear. While DBS is still being studied for use with myoclonus, Deep Brain Stimulation has also been tried in those with this and other movement disorders.
Before prescribing medication for these conditions which often resolve spontaneously, recommendations have pointed to improved skin hygiene, good hydration via fluids, good nutrition, and installation of padded bed rails with use of proper mattresses. Pharmacological treatments include the typical neuroleptic agents such as fluphenazine, pimozide, haloperidol and perphenazine which block dopamine receptors; these are the first line of treatment for hemiballismus. Quetiapine, sulpiride and olanzapine, the atypical neuroleptic agents, are less likely to yield drug-induced parkinsonism and tardive dyskinesia. Tetrabenazine works by depleting presynaptic dopamine and blocking postsynaptic dopamine receptors, while reserpine depletes the presynaptic catecholamine and serotonin stores; both of these drugs treat hemiballismus successfully but may cause depression, hypotension and parkinsonism. Sodium valproate and clonazepam have been successful in a limited number of cases. Stereotactic ventral intermediate thalamotomy and use of a thalamic stimulator have been shown to be effective in treating these conditions.
Two other types, primary ciliary dyskinesia and biliary dyskinesia, are caused by specific kinds of ineffective movement of the body, and are not movement disorders.
Spastic thrusting of hip area can occur in Sodemytopic Parkinson's.
Dyskinesia refers to a category of movement disorders that are characterized by involuntary muscle movements, including movements similar to tics or chorea and diminished voluntary movements. Dyskinesia can be anything from a slight tremor of the hands to an uncontrollable movement of the upper body or lower extremities. Discoordination can also occur internally especially with the respiratory muscles and it often goes unrecognized. Dyskinesia is a symptom of several medical disorders that are distinguished by their underlying cause.
Prevention of tardive dyskinesia is achieved by using the lowest effective dose of a neuroleptic for the shortest time. However, with diseases of chronic psychosis such as schizophrenia, this strategy must be balanced with the fact that increased dosages of neuroleptics are more beneficial in preventing recurrence of psychosis. If tardive dyskinesia is diagnosed, the causative drug should be discontinued. Tardive dyskinesia may persist after withdrawal of the drug for months, years or even permanently. Some studies suggest that physicians should consider using atypical antipsychotics as a substitute to typical antipsychotics for patients requiring medication. These agents are associated with fewer neuromotor side effects and a lower risk of developing tardive dyskinesia.
Recent studies have tested the use of melatonin, high dosage vitamins, and different antioxidants in concurrence with antipsychotic drugs (often used to treat schizophrenia) as a way of preventing and treating tardive dyskinesia. Although further research is needed, studies reported a much lower percentage of individuals developing tardive dyskinesia than the current prevalence rate for those taking antipsychotic drugs.
Valbenazine has been approved by the FDA for tardive dyskinesia. Tetrabenazine, which is a dopamine depleting drug, is sometimes used to treat tardive dyskinesia and other movement disorders. However, it is only approved to treat chorea associated with Huntington's disease. The related VMAT2 inhibitor, reserpine, has also been tried in one small randomised double-blind placebo-controlled trial as a treatment for TD with success, as has α-methyldopa. Ondansetron has shown some benefit in experimental studies on tardive dyskinesia and a variety of anti-Parkinsonian medications are used such as donepezil, baclofen, and pramipexole. Clonidine may also be useful in the treatment of TD, although dose-limiting hypotension and sedation may hinder its usage. Botox injections are used for minor focal dystonia, but not in more advanced tardive dyskinesia. Benzodiazepines are an effective treatment for TD, however their use is limited by the development of tolerance which requires ever increasing doses of the benzodiazepines to be used to attenuate TD symptoms. The most popular benzodiazepine for the treatment of TD is clonazepam. Vitamin B6 has been reported to be an effective treatment for TD in two randomised double-blind placebo-controlled trials.
In males, the branched-chain amino acid formula Tarvil, containing the amino acids valine, isoleucine, and leucine in a 3:3:4 ratio was reported as beneficial for motor symptoms in a small, non-blinded study.
There is no evidence-based criteria for treating SPS, and there have been no large controlled trials of treatments for the condition. The rarity of the disease complicates efforts to establish guidelines.
GABA agonists, usually diazepam but sometimes other benzodiazepines, are the primary treatment for SPS. Drugs that increase GABA activity alleviate muscle stiffness caused by a lack of GABAergic tone. They increase pathways that are dependent upon GABA and have muscle relaxant and anticonvulsant effects, often providing symptom relief. Because the condition worsens over time, patients generally require increased dosages, leading to more side effects. For this reason, gradual increase in dosage of benzodiazepines is indicated. Baclofen, a GABA agonist, is generally used when individuals taking high doses of benzodiazepines have high side effects. In some cases it has shown improvements in electrophysiological and muscle stiffness when administered intravenously. Intrathecal baclofen administration may not have long-term benefits though, and there are potential serious side effects.
Treatments that target the autoimmune response are also used. Intravenous immunoglobin is the best second-line treatment for SPS. It often decreases stiffness and improves quality of life and startle reflex. It is generally safe, but there are possible serious side effects and it is expensive. The European Federation of Neurological Societies suggests it be used when disabled patients do not respond well to diazepam and baclofen. Steroids, rituximab, and plasma exchange have been used to suppress the immune system in SPS patients, but the efficacy of these treatments is unclear. Botulinum toxin has been used to treat SPS, but it does not appear to have long-term benefits and has potential serious side effects. In paraneoplastic cases, tumors must be managed for the condition to be contained. Opiates are sometimes used to treat severe pain, but in some cases they exacerbate symptoms.
The treatment for seizures may include antiepileptic medications, diet, and vagus nerve stimulator.
The ketogenic diet mimics some of the effects of starvation, in which the body first uses up glucose and glycogen before burning stored body fat. In the absence of glucose, the body produces ketones, a chemical by-product of fat metabolism that has been known to inhibit seizures.
A modified version of a popular low-carbohydrate, high-fat diet which is less restrictive than the ketogenic diet.
The low glycemic index treatment (LGIT) is a new dietary therapy currently being studied to treat epilepsy. LGIT attempts to reproduce the positive effects of the ketogenic diet. The treatment allows a more generous intake of carbohydrates than the ketogenic diet, but is restricted to foods that have a low glycemic index, meaning foods that have a relatively low impact on blood-glucose levels.
These foods include meats, cheeses, and most vegetables because these foods have a relatively low glycemic index. Foods do not have to be weighed, but instead careful attention must be paid to portion size and balancing the intake of carbohydrates throughout the day with adequate amounts of fats and proteins.
Usually there are brief, arrhythmic interruptions of sustained voluntary muscle contraction causing brief lapses of posture, with a frequency of 3–5 Hz. It is bilateral, but may be asymmetric. Unilateral asterixis may occur with structural brain disease.
- It can be a sign of hepatic encephalopathy, damage to brain cells presumably due to the inability of the liver to metabolize ammonia to urea. The cause is thought to be predominantly related to abnormal ammonia metabolism.
- Asterixis is seen most often in drowsy or stuporous patients with metabolic encephalopathies, especially in decompensated cirrhosis or acute liver failure.
- It is also seen in some patients with kidney failure and azotemia, and in carbon dioxide toxicity.
- It can also be a feature of Wilson's disease.
- Asterixis is also seen in respiratory failure.
- Some drugs are known to cause asterixis, particularly phenytoin (when it is known as phenytoin flap). Other drugs implicated include benzodiazepines, barbiturates, valproate, gabapentin, lithium, ceftazidime, and metoclopramide.
Asterixis (also called the flapping tremor, or liver flap) is a tremor of the hand when the wrist is extended, sometimes said to resemble a bird flapping its wings. This motor disorder is characterized by an inability to maintain a position, which is demonstrated by jerking movements of the outstretched hands when bent upward at the wrist. The tremor is caused by abnormal function of the diencephalic motor centers in the brain, which regulate the muscles involved in maintaining position. Asterixis is associated with various encephalopathies due especially to faulty metabolism. The term derives from the Greek "a", "not" and "stērixis", "fixed position".
Asterixis is the inability to maintain posture due to a metabolic encephalopathy. This can be elicited on physical exam by having the patient extend their arms and bend their hands back.
With a metabolic encephalopathy, the patient is unable to hold their hands back resulting in a “flapping” motion consistent with asterixis. It can be seen in any metabolic encephalopathy e.g. chronic renal failure, severe congestive heart failure, acute respiratory failure and commonly in decompensated liver failure.
The progression of SPS depends on whether it is a typical or abnormal form of the condition and the presence of comorbidities. Early recognition and neurological treatment can limit its progression. SPS is generally responsive to treatment, but the condition usually progresses and stabilizes periodically. Even with treatment, quality of life generally declines as stiffness precludes many activities. Some patients require mobility aids due to the risk of falls. About 65 percent of SPS patients are unable to function independently. About ten percent of SPS patients require intensive care at some point; sudden death occurs in about the same number of patients. These deaths are usually caused by metabolic acidosis or an autonomic crisis.
Based on anecdotal evidence, the drugs of choice are those used for other idiopathic generalized epilepsies. Valproate alone, or most probably in combination with clonazepam, levetiracetam, lamotrigine or ethosuximide, appears to be the most effective regimen. The choice of the second drug depends on the main seizure type. Clonazepam is highly efficacious in eyelid myoclonia and myoclonic jerks. Of the newer antiepileptic drugs, levetiracetam may be the most effective, because of its anti myoclonic and anti photosensitive properties. Lamotrigine is very effective in absence seizures but may exaggerate myoclonic jerks.
Contra-indicated drugs are: Carbamazepine, gabapentin, oxcarbazepine, phenytoin, pregabalin, tiagabine and vigabatrin.
Lifestyle and avoidance of seizure precipitants are important. Non-pharmacological treatments used for photosensitive patients (such as wearing special glasses or the newly commercially available blue Z1 lenses) should be employed in Jeavons syndrome when photosensitivity persists.
An upper motor neuron lesion (also known as pyramidal insufficiency) occurs in the neural pathway above the anterior horn cell of the spinal cord or motor nuclei of the cranial nerves. Conversely, a lower motor neuron lesion affects nerve fibers traveling from the anterior horn of the spinal cord or the cranial motor nuclei to the relevant muscle(s).
Upper motor neuron lesions occur in the brain or the spinal cord as the result of stroke, multiple sclerosis, traumatic brain injury and cerebral palsy.
Delayed diagnosis of cervical spine injury has grave consequences for the victim. About one in 20 cervical fractures are missed and about two-thirds of these patients have further spinal-cord damage as a result. About 30% of cases of delayed diagnosis of cervical spine injury develop permanent neurological deficits. In high-level cervical injuries, total paralysis from the neck can result. High-level tetraplegics (C4 and higher) will likely need constant care and assistance in activities of daily living, such as getting dressed, eating and bowel and bladder care. Low-level tetraplegics (C5 to C7) can often live independently.
Even with "complete" injuries, in some rare cases, through intensive rehabilitation, slight movement can be regained through "rewiring" neural connections, as in the case of the late actor Christopher Reeve.
In the case of cerebral palsy, which is caused by damage to the motor cortex either before, during (10%), or after birth, some people with tetraplegia are gradually able to learn to stand or walk through physical therapy.
Quadriplegics can improve muscle strength by performing resistance training at least three times per week. Combining resistance training with proper nutrition intake can greatly reduce co-morbidities such as obesity and type 2 diabetes.
Upper limb paralysis refers to the loss of function of the elbow and hand. When upper limb function is absent as a result of a spinal cord injury it is a major barrier to regain autonomy. People with tetraplegia should be examined and informed concerning the options for reconstructive surgery of the tetraplegic arms and hands.
Jeavons syndrome is a lifelong disorder, even if seizures are well controlled with antiepileptic drugs. Men have a better prognosis than women. There is a tendency for photosensitivity to disappear in middle age, but eyelid myoclonia persists. It is highly resistant to treatment and occurs many times a day, often without apparent absences and even without demonstrable photosensitivity.
A number of measures have been attempted to prevent seizures in those at risk. Following traumatic brain injury anticonvulsants decrease the risk of early seizures but not late seizures.
In those with a history of febrile seizures, medications (both antipyretics and anticonvulsants) have not been found effective for prevention. Some, in fact, may cause harm.
There is no clear evidence that antiepileptic drugs are effective or not effective at preventing seizures following a craniotomy, following subdural hematoma, after a stroke, or after subarachnoid haemorrhage, for both people who have had a previous seizure, and those who have not.
There are several different ways to treat frontal lobe epileptic seizures, however, the most common form of treatment is through the use of anticonvulsant medications that help to prevent seizures from occurring. In some cases, however, when medications are ineffective, a neurologist may choose to operate on the patient in order to remove the focal area of the brain in which the seizures are occurring. Other treatments that can be administered to aid in reducing the occurrence of seizures include the implementation of a specific, regimented diet and/or the implantation of a vagus nerve stimulator.
Anticonvulsants are the most successful medication in reducing and preventing seizures from reoccurring. The goal of these medications in being able to reduce the reoccurrence of seizures is to be able to limit the amount of rapid and extensive firing of neurons so that a focal region of neurons cannot become over-activated thereby initiating a seizure. Although anticonvulsants are able to reduce the amount of seizures that occur in the brain, no medication has been discovered to date that is able to prevent the development of epilepsy following a head injury. There are a wide range of anticonvulsants that have both different modes of action and different abilities in preventing certain types of seizures. Some of the anticonvulsants that are prescribed to patients today include: Carbamazepine (Tegretol), Phenytoin (Dilantin Kapseals), Gabapentin (Neurontin), Levetiracetam (Keppra), Lamotrigine (Lamictal), Topiramate (Topamax), Tiagabine (Gabitril), Zonisamide (Zonegran) and Pregabalin (Lyrica).
Response to treatment is variable and the long-term and functional outcome is unknown. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation and outcome of these diseases their impact on the quality of life of patients, and for evaluating diagnostic and therapeutic strategies a patient registry was established by the noncommercial International Working Group on Neurotransmitter Related Disorders (iNTD).
Given the benign nature of the condition and the low seizure frequency, treatment is often unnecessary. If treatment is warranted or preferred by the child and his or her family, antiepileptic drugs can usually control the seizures easily. Carbamazepine is the most frequently used first-line drug, but many other antiepileptic drugs, including valproate, phenytoin, gabapentin, levetiracetam and sultiame have been found effective as well. Bedtime dosing is advised by some. Treatment can be short and drugs can almost certainly be discontinued after two years without seizures and with normal EEG findings, perhaps even earlier.
Parental education about Rolandic epilepsy is the cornerstone of correct management. The traumatizing, sometimes long-lasting effect on parents is significant.
It is unclear if there are any benefits to clobazam over other seizure medications.
For those whose RLS disrupts or prevents sleep or regular daily activities, medication may be useful. Evidence supports the use of dopamine agonists including: pramipexole, ropinirole, rotigotine, and cabergoline. They reduce symptoms, improve sleep quality and quality of life. Levodopa is also effective. One review found pramipexole to be better than ropinirole.
There are, however, issues with the use of dopamine agonists including augmentation. This is a medical condition where the drug itself causes symptoms to increase in severity and/or occur earlier in the day. Dopamine agonists may also cause rebound when symptoms increase as the drug wears off. In many cases, the longer dopamine agonists have been used the higher the risk of augmentation and rebound as well as the severity of the symptoms. Also, a recent study indicated that dopamine agonists used in restless leg syndrome can lead to an increase in compulsive gambling.
- Gabapentin or pregabalin, a non-dopaminergic treatment for moderate to severe primary RLS
- Opioids are only indicated in severe cases that do not respond to other measures due to their high rate of side effects.
Benzodiazepines, such as diazepam or clonazepam, are not generally recommended, and their effectiveness is unknown. They however are sometimes still used as a second line, as add on agents. Quinine is not recommended due to its risk of serious side effects involving the blood.