Epilepsy

A tendency to have recurrent seizures. In many people with epilepsy, the cause is unclear, although a genetic factor may be involved. In other cases, seizures may be the result of brain damage from head injury, birth trauma, brain infection (such as meningitis or encephalitis), brain tumour, stroke, drug intoxication, or a metabolic disorder. Many people with epilepsy do not have any symptoms between seizures. Some people experience an aura shortly before. In some cases, a stimulus such as a flashing light triggers a seizure. Epileptic seizures may occur more frequently in times of illness or stress. Epileptic seizures can be classified into two groups: generalized and partial. Generalized seizures cause loss of consciousness and may affect all areas of the brain. There are two types: grand mal and absence (petit mal) seizures. During a grand mal seizure, there may be an aura initially, then the body becomes stiff and consciousness is lost; breathing may be irregular or may stop briefly, then the body jerks uncontrollably. The person may be disorientated for hours afterwards and have no memory of the event. Prolonged grand mal seizures are potentially life-threatening. Absence seizures occur mainly in children. Periods of altered consciousness last for only a few seconds and there are no abnormal movements of the body. This type of seizure may occur hundreds of times daily. Partial seizures are caused by abnormal electrical activity in a more limited area of the brain. They may be simple or complex. In simple partial seizures, consciousness is not lost and an abnormal twitching movement, tingling sensation, or hallucination of smell, vision, or taste occurs, lasting several minutes. In complex partial seizures, also known as temporal lobe epilepsy, conscious contact with the surroundings is lost. The sufferer becomes dazed and may behave oddly. Typically, the person remembers little, if any, of the event. Diagnosis is made from examination of the nervous system and an EEG. CT scanning or MRI of the brain and blood tests may also be carried out. Anticonvulsant drugs usually stop or reduce the frequency of seizures. Surgery may be considered if a single area of brain damage is causing the seizures. Epilepsy that develops during childhood may disappear following adolescence.