What is Myoclonic Epilepsy?
Epilepsy is a group of neurological syndromes that stem from the brain and affect the nervous system. Myoclonic epilepsy primarily evidences through seizures in the neck, shoulders, and upper arms. There are several types of myoclonic epilepsy, and not all myoclonic seizures are indicative of epilepsy.
There are many types of epilepsy, classified according to a number of factors, such as the age of onset of the disease, the type of seizures, the portion of the brain involved, the cause of the condition, and what triggers the episodes. Epilepsy in some form occurs in about 1 out of every 1000 – 2000 people. A seizure is caused by a sudden burst of electrical activity in a portion of the brain.
Myoclonus is a type of seizure which presents as a brief episode of involuntary muscle twitching, primarily in the neck, shoulders and upper arms. These usually occur in the morning shortly after waking up. Most people have occasional myoclonic episodes such as hiccups or sleep starts, yet never develop epilepsy.
Juvenile myoclonic epilepsy (JME) is one of the most common forms of the disease. It accounts for between 5% and 10% of all epileptic syndromes. It is generally a genetic condition that appears between the ages of 12 and 18.
Clinical histories of patients with JME reveal that many of them experienced absence seizures as young children. An absence seizure involves a moment of staring when the person is non-responsive to any outside stimuli. These usually pass quickly, and the person having the seizure is generally unaware that anything unusual has occurred. Children who have these regularly have a condition called childhood absence epilepsy (CAE). About 15% of children with CAE eventually develop JME.
Individuals with JME generally do not loose consciousness during seizures and have average intelligence. While there is no cure for myoclonic epilepsy, JME seizures can usually be controlled successfully through medication. The medicine must be taken for life; however, patients with JME can generally participate in normal activities unhindered by the condition.
A much more debilitating group of epileptic disorders is progressive myoclonic epilepsy (PME). These include, among others, Dravet syndrome, Unverrict-Lundborg disease, Lafora disease, and mitochondrial encephalopathies. PME patients experience both myoclonic and tonic-clonic seizures.
A tonic-clonic seizure, once called grand mall, begins with a sudden tightening of the body’s muscles. The person loses consciousness, falls down, and then begins to shake all over. This type of seizure is damaging not only physically, but causes a loss of metal ability as well. Treatment is very difficult, since drugs often lose their effectiveness in controlling the seizures after a short period of time.
Several genes have been identified as causing certain forms of epilepsy, which is a significant step forward in predicting and eventually preventing the disease. While there is currently no cure for epilepsy, great strides have been made in treatment. Most people who are diagnosed with myoclonic epilepsy can lead normal lives with medication.
Written by Brenda Scott
