The Merck Manual Home Edition notes that about 2 percent of people have a seizure, a neurological condition in which irregular electrical activity occurs in the brain. Seizures can affect one part of the brain, called a partial seizure, or the entire brain, called a generalized seizure. The Neurology Channel points out that a common type of generalized seizure is a myoclonic seizure.
Types
Epilepsy.com defines three types of epilepsy in which myoclonic seizures occur: Lennox-Gastaut syndrome, juvenile myoclonic epilepsy and progressive myoclonic epilepsy. With Lennox-Gastaut syndrome, patients have myoclonic seizures that involve the upper arms, neck, shoulders and face. These seizures are strong and may become difficult to control. Juvenile myoclonic epilepsy patients have seizures soon after waking up that involve the shoulders, neck and upper arms. With progressive myoclonic epilepsy, patients have a combination of myoclonic and tonic-clonic seizures, another type of seizure that includes a loss of consciousness and jerking movements.
Time Frame
Myoclonic seizures do not last long. Epilepsy.com explains that each seizure lasts about one to two seconds. The Neurology Channel adds that most cases of myoclonic seizures start by age 5 and can continue into adulthood.
Symptoms
The Epilepsy Foundation explains that myoclonic seizures are characterized by sudden muscle contractions. Patients can appear like they are twitching, which can be subtle or more noticeable. These muscle contractions affect both sides of the patient's body at the same time. A loss of consciousness does not occur during a myoclonic seizure.
Treatment
The treatment of myoclonic seizures depend on the type. For example, myoclonic seizures with Lennox-Gastaut syndrome may not respond to antiepileptic drugs. Patients may get some symptom relief with certain antiepileptics, such as valproic acid, rufinamide, lamotrigine, clonazepam, topiramate or felbamate. Other treatment options include vagus nerve stimulation and callostomy, a surgery that cuts the connection between the two brain hemispheres. Epilepsy.com points out that medication, such as valproate, control 80 percent of seizures in juvenile myoclonic epilepsy. With progressive myoclonic epilepsy, the medication only works for a limited amount of time. Epilepsy.com adds that doctors use valproate for progressive myoclonic epilepsy most often, followed by topiramate, levetiracetam and clonazepam.
Prognosis
Some myoclonic seizure patients have a better prognosis that others. Epilepsy.com explains that myoclonic seizures with juvenile myoclonic epilepsy are well controlled with medication. But patients with progressive myoclonic epilepsy do not have a favorable prognosis and can lose their movement and thinking abilities.
