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In the past, dopamine blocking agents have been used in the treatment of spasmodic torticollis. Treatment was based on the theory that there is an imbalance of the neurotransmitter dopamine in the basal ganglia. These drugs have fallen out of fashion due to various serious side effects: sedation, parkinsonism, and tardive dyskinesia.
Other oral medications can be used in low doses to treat early stages of spasmodic torticollis. Relief from spasmodic torticollis is higher in those patients who take anticholinergic agents when compared to other oral medications. Many have reported complete management with gabapentin alone or in combination with another drug such as clonazepam. 50% of patients who use anticholinergic agents report relief, 21% of patients report relief from clonazepam, 11% of patients report relief from baclofen, and 13% from other benzodiazepines.
Higher doses of these medications can be used for later stages of spasmodic torticollis; however, the frequency and severity of side effects associated with the medications are usually not tolerated. Side effects include dry mouth, cognitive disturbance, drowsiness, diplopia, glaucoma and urinary retention.
The most commonly used treatment for spasmodic torticollis is the use of botulinum toxin injection in the dystonic musculature. Botulinum toxin type A is most often used; it prevents the release of acetylcholine from the presynaptic axon of the motor end plate, paralyzing the dystonic muscle. By disabling the movement of the antagonist muscle, the agonist muscle is allowed to move freely. With botulinum toxin injections, patients experience relief from spasmodic torticollis for approximately 12 to 16 weeks. There are several type A preparations available worldwide; however Botox and Dysport are the only preparations approved by the U.S. Food and Drug Administration (FDA) for clinical use in the United States.
Some patients experience or develop immunoresistance to botulinum toxin type A and must use botulinum toxin type B. Approximately 4% to 17% of patients develop botulinum toxin type A antibodies. The only botulinum toxin type B accessible in the United States is Myobloc. Treatment using botulinum toxin type B is comparable to type A, with an increased frequency of the side effect dry mouth.
Common side effects include pain at the injection site (up to 28%), dysphagia due to the spread to adjacent muscles (11% to 40%), dry mouth (up to 33%), fatigue (up to 17%), and weakness of the injected or adjacent muscle (up to 56%). A Cochrane review published in 2016 reported moderate-quality evidence that a single Botulinum toxin-B treatment session could improve cervical dystonia symptoms by 10% to 20%, although with an increased risk of dry mouth and swallowing difficulties.
To date, there is no single, universal treatment that has been found to cure myoclonus dystonia. However, there are several treatment methods that have been found to be effective for helping to reduce the symptoms associated with the syndrome.
Surgery, such as the denervation of selected muscles, may also provide some relief; however, the destruction of nerves in the limbs or brain is not reversible and should be considered only in the most extreme cases. Recently, the procedure of deep brain stimulation (DBS) has proven successful in a number of cases of severe generalised dystonia. DBS as treatment for medication-refractory dystonia, on the other hand, may increase the risk of suicide in patients. However, reference data of patients without DBS therapy are lacking.
In some cases Meige's syndrome can be reversed when it is caused by medication. It has been theorized that it is related to cranio-mandibular orthopedic misalignment, a condition that has been shown to cause a number of other movement disorders (Parkinon's, tourettes, and torticollis). This theory is supported by the fact that the trigeminal nerve is sensory for blink reflex, and becomes hypertonic with craniomandibular dysfunction. Palliative treatments are available, such as botulinum toxin injections.
Reducing the types of movements that trigger or worsen dystonic symptoms provides some relief, as does reducing stress, getting plenty of rest, moderate exercise, and relaxation techniques. Various treatments focus on sedating brain functions or blocking nerve communications with the muscles via drugs, neuro-suppression, or denervation. All current treatments have negative side-effects and risks.
A "geste antagoniste" is a physical gesture or position (such as touching one's chin) which serves to temporarily interrupt dystonia, it is also known as a "sensory trick". Patients may be aware of the presence of a geste antagoniste which provides some relief from their symptoms. Therapy for dystonia can involve prosthetics which provide passive simulation of the stimulation.
Benzodiazepines such as clonazepam improve tremors caused by the myoclonus aspect of this syndrome by binding allosterically to GABA ionotropic receptors, causing an influx of chloride ions that produce an inhibitory effect that can calm myoclonic jerks.
There is no cure for torsion dystonia. However, there are several medical approaches that can be taken in order to lessen the symptoms of the disease. The treatment must be patient specific, taking into consideration all of the previous and current health complications. The doctor that creates the treatment must have intimate knowledge of the patients’ health and create a treatment plan that covers all of the symptoms focusing on the most chronic areas.
The first step for most with the disorder begins with some form of physical therapy in order for the patient to gain more control over the affected areas. The therapy can help patients with their posture and gain control over the areas of their body that they have the most problems with.
The second step in the treatment process is medication. The medications focus on the chemicals released by neurotransmitters in the nervous system, which control muscle movement. The medications on the market today are anticholinergics, benzodiazepines, baclofen, dopaminergic agents/dopamine-depleting agents, and tetrabenazine. Each medication is started on a low dosage and gradually increased to higher doses as the disease progresses and the side effects are known for the individual.
A more site-specific treatment is the injection of botulinum toxin. It is injected directly into the muscle and works much the same way the oral medications do—by blocking neurotransmitters. The injections are not a treatment for the disease, but are a means to control its symptoms.
A fourth option in the treatment for the symptoms of torsion dystonia is surgery. Surgery is performed only if the patient does not respond to the oral medications or the injections. The type of surgery performed is specific to the type of dystonia that the patient has.
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.
This condition is often treated with injections of botox, a commercially prepared form of botulinum toxin. Botox reduces the symptoms of the disorder but it is not a cure for dystonia. Since the root of the problem is neurological, doctors have explored sensorimotor retraining activities to enable the brain to "rewire" itself and eliminate dystonic movements. The work of several doctors such as Nancy Byl and Joaquin Farias has shown that sensorimotor retraining activities and proprioceptive stimulation can induce neuroplasticity, making it possible for patients to recover substantial function that was lost to focal dystonia.
Anticholinergics such as Artane can be prescribed for off-label use, as some sufferers have had success.
Bass guitarist and instructor Scott Devine said that he wears a glove while playing bass guitar because of the condition. He finds that the glove stops the involuntary finger movements. He says it works for him but does not suggest that it may work for everyone with the condition.
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.
Although dystonias may be induced by chemical exposure/ingestion, brain injury, or hereditary/genetic predisposition, the task-specific focal dystonias such as writer's cramp are a unique challenge to diagnose and treat. Some cases may respond to chemical injections - botulinum toxin (botox) is often cited, though it is not helpful in all cases. Behavioral retraining attempts may include writing devices, switching hands, physical therapy, biofeedback, constraint-induced motion therapy, and others. Some writing instruments allow variations of pressure application for use. None of these are effective in all cases, however. The work of Dr. Joaquin Farias has shown that proprioceptive stimulation can induce neuroplasticity, making it possible for patients to recover substantial function that was lost from focal dystonia.
Anticholinergics such as Artane can be prescribed for off-label use, as some sufferers have had success.
Although essential tremor is often mild, people with severe tremor have difficulty performing many of their routine activities of daily living. ET is generally progressive in most cases (sometimes rapidly, sometimes very slowly), and can be disabling in severe cases.
Not all individuals with ET require treatment, but there are many treatment options depending on symptom severity. Caffeine and stress should be avoided, and good sleep is recommended.
When symptoms are sufficiently troublesome to warrant treatment, the first medication choices are beta blockers such as propranolol or alternately, nadolol and timolol. Atenolol and pindolol are not effective for tremor. The anti-epileptic primidone is also effective for ET.
Second-line or third-line medications can be added if the first-line medications do not control the tremor. Second-line medications are the anti-epileptics topiramate, gabapentin (as monotherapy) and levetiracetam, or benzodiazepines like alprazolam. Third-line medications are clozapine and mirtazapine.
Theophylline has been used by some practitioners to treat ET, even though it may also induce tremor. However, its use is debated due to conflicting data on its efficacy. There is some evidence that low doses may lead to improvement.
Ethanol has shown superior efficacy to that of benzodiazepines in small trials. It improves tremor in small doses and its effects are usually noticeable within 20 minutes for 3–5 hours, but occasionally appears a rebound tremor augmentation later.
When medications do not control the tremor or the person does not tolerate medication, botulinum toxin, deep brain stimulation or occupational therapy can be helpful. The electrodes for deep brain stimulation are usually placed in the "tremor center" of the brain, the ventral intermediate nucleus of the thalamus.
Additionally, MRI-guided high intensity focused ultrasound is a non-surgical treatment option for people with essential tremor who have not seen improvement with medication and refused or are not valid candidates for other techniques, such as deep brain stimulation. MRI-guided high intensity focused ultrasound does not achieve healing but can improve the quality of life. However, its safety, efficacy and long-term effects are not yet established. Temporary and permanent adverse side effects have been documented, and also the reappearance of tremors. Possible adverse events include gait difficulties, balance disturbances, paresthesias, headache, hemorrhage in the treated area (which requiries emergency treatment), tissue damage in other areas, skin burns with ulcerations, skin retraction, scars and blood clots. This procedure is contraindicated in pregnant women, persons who have a non-MRI compatible implanted metallic devices, allergy to MR contrast agents, cerebrovascular disease, abnormal bleeding, hemorrhage and/or blood clotting disorders, advanced kidney disease or on dialysis, heart conditions, severe hypertension, ethanol or substance abuse, among others. The US Food and Drug Administration ("FDA") approved Insightec’s Exablate Neuro system to treat essential tremor in 2016.
PED patients usually avoid prolonged, continuous exertion to prevent occurrence of attacks. Use of anticonvulsants such as benzodiazepines show little to no success in PED patients. A few cases have shown that patients were able to lessen their attacks with a high carbohydrate snack. A new approach to managing PED is the ketogenic diet, which alters the primary cerebral energy metabolism from glucose to ketone bodies. Reports have shown that the ketonic diet protects against seizures in epilepsy. In PED, it is probable that ketones will provide sufficient energy for the basal ganglia, which is normally deficient in patients with PED.
Treatment for PKND is more difficult than other Paroxysmal Dyskinesias. The majority of patients experience some relief from low dosages of clonazepam, a muscle relaxant and anticonvulsant. Similar to PKD, avoidance of stress, excitement, and fatigue will lower the frequency of PNKD attacks. Many patients also avoid known methyglyoxal containing foods and beverages such as alcohol, coffee, tea, and chocolate.
Oromandibular dystonia is a form of focal dystonia affecting the mouth, jaw and tongue, and in this disease it is hard to speak. It is associated with bruxism.
Botulinum toxin has been used in treatment.
Since the root of the problem is neurological, doctors have explored sensorimotor retraining activities to enable the brain to "rewire" itself and eliminate dystonic movements. The work of several doctors such as Nancy Byl and Joaquin Farias has shown that sensorimotor retraining activities and proprioceptive stimulation can induce neuroplasticity, making it possible for patients to recover substantial function that was lost due to Cervical Dystonia, oromandibular dystonia and dysphonia.
Recent research indicates that the biomolecule taurine may be effective for hypertonia, perhaps through its benzodiazepine-like modulation of the inhibitory neurotransmitter GABA or the neuromuscular effects of increasing intracellular calcium levels.
A 1969 study of torsion dystonia patients found an average IQ 10 points higher than controls matched for age, sex and ethnic background.
Anticholinergic drugs are used to control neuroleptic-induced EPS, although akathisia may require beta blockers or even benzodiazepines. If the EPS are induced by an antipsychotic, EPS may be reduced by dose titration or by switching to an atypical antipsychotic, such as aripiprazole, ziprasidone, quetiapine, olanzapine, risperidone, or clozapine. These medications possess an additional mode of action that is believed to negate their effect on the nigrostriatal pathway, which means they are associated with fewer extrapyramidal side-effects than "conventional" antipsychotics (chlorpromazine, haloperidol, etc.), although some research has shown that second generation neuroleptics cause EPS at the same rate as the first generation drugs.
Commonly used medications for EPS are anticholinergic agents such as benztropine (Cogentin), diphenhydramine (Benadryl), and trihexyphenidyl (Artane). Another common course of treatment includes dopamine agonist agents such as pramipexole. These medications reverse the symptoms of extrapyramidal side effects caused by antipsychotics or other drugs that either directly or indirectly inhibit dopaminergic neurotransmission.
Studies are yet to be undertaken on the optimum dosage of the causative drugs to reduce their side effects (extrapyramidal symptoms (EPS)).
There are a number of potential treatments for spasmodic dysphonia, including botox, surgery and voice therapy. A number of medications have also been tried including anticholinergics (such as benztropine) which have been found to be effective in 40-50% of people, but which are associated with a number of side effects.
Therapeutic interventions are best individualized to particular patients.
Basic principles of treatment for hypertonia are to avoid noxious stimuli and provide frequent range of motion exercise.
The main symptoms involve involuntary blinking and chin thrusting. Some patients may experience excessive tongue protrusion, squinting, light sensitivity, muddled speech, or uncontrollable contraction of the platysma muscle. Some Meige's patients also have "laryngeal dystonia" (spasms of the larynx). Blepharospasm may lead to embarrassment in social situations, and oromandibular dystonia can affect speech, making it difficult to carry on the simplest conversations. This can cause difficulty in both personal and professional contexts, and in some cases may cause patients to withdraw from social situations.
The condition tends to affect women more frequently than men.
Voice therapy appears to be ineffective in cases of true spasmodic dysphonia, however as it is difficult to distinguish between spasmodic dysphonia and functional dysphonias and misdiagnosis is relatively common, a trial of voice therapy is often recommended before more invasive procedures are tried. Some also state that it is useful for mild symptoms and as an add-on to botox therapy and others report success in more severe cases. Laryngeal manual therapy, which is massaging of the neck and cervical structures, also shows positive results for intervention of functional dysphonia.
Current medical science does not precisely describe the causes of dystonia. Misfiring of neurons in the sensorimotor cortex, a thin layer of neural tissue that covers the brain, is thought to cause contractions. This misfiring may result from impaired inhibitory mechanisms during muscle contraction. When the brain tells a given muscle to contract, it simultaneously silences muscles that would oppose the intended movement. It appears that dystonia interferes with the brain's ability to inhibit those surrounding muscles, leading to loss of selectivity.
The sensorimotor cortex is organized as discrete "maps" of the human body. Under normal conditions, each body part (such as individual fingers) occupies a distinct area on these cortical maps. In dystonia, these maps lose their distinct borders and overlap occurs. Exploration of this initially involved over-training particular finger movements in non-human primates, which resulted in the development of focal hand dystonia. Examination of the primary somatosensory cortex in the trained animals showed grossly distorted representations of the maps pertaining to the fingers when compared to the untrained animals. Additionally, these maps in the dystonic animals had lost the distinct borders that were noted in the untrained animals.
Imaging studies in humans with focal dystonia have confirmed this finding. Also, synchronous afferent stimulation of peripheral muscles induces organizational changes in motor representations, characterized both by an increase in map size of stimulated muscles and a reduction in map separation, as assessed using transcranial magnetic stimulation.
The cross-connectivity between areas that are normally segregated in the sensory cortex may prevent normal sensorimotor feedback and so contribute to the observed co-contraction of antagonist muscle groups, and inappropriately timed and sequenced movements that underlie the symptoms of focal dystonia. It is hypothesized that a deficit in inhibition caused by a genetically mediated loss of inhibitory interneurons may be the underlying cause of the deficits observed in dystonia.
While usually painless, in some instances the sustained contraction and abnormal posturing in dystonia cause pain. Focal dystonia most typically affects people who rely on fine motor skills—musicians, writers, surgeons, etc. It is thought that the excessive motor training those skills require may contribute to the development of dystonia as their cortical maps become enlarged and begin to overlap. Focal dystonia is generally "task-specific," meaning that it is only problematic during certain activities.