Glossary of Epilepsy Terms
Electroencephalogram (EEG): a diagnostic test that measures brainwaves, the electrical impulses in the cerebral cortex. This test helps a doctor to diagnose epilepsy.
Epilepsy surgery: a neuro-surgical procedure to prevent further seizures, usually accomplished by resecting the epileptogenic zone. Successful in eliminating seizures in a large majority of patients, depending on the type of epilepsy identified during EEG-video monitoring.
Extratemporal cortical resection: an operation to cut out (resect) brain tissue that contains a seizure focus. "Extratemporal" means the tissue is located in an area of the brain other than the temporal lobe, most often the frontal lobe.
Functional hemispherectomy: a procedure in which portions of one hemisphere of the brain which is not functioning normally are removed, and the corpus callosum is split. This interrupts the communications among the various lobes and between the two hemispheres and prevents the spread of seizures.
Hemisphere: one half of the cerebrum, the largest part of the brain.
Generalized seizure: a seizure that occurs all through the brain.
Grand-mal seizure: an older term for a seizure in which the patient loses consciousness and collapses. The patient also has body stiffening and violent jerking, and then often goes into a deep sleep. Also known as a generalized convulsion.
Ketogenic diet: a treatment for epilepsy intended to maintain the starvation or fasting metabolism for a long period in order to create ketones, byproducts of fat-burning metabolism. Seizures often lessen or disappear during periods of fasting. The diet is very high in fat and low in carbohydrates and is most often recommended for children ages 2 through 12 who have been diagnosed with a generalized type of epilepsy, and who have failed to respond to a variety of medications.
Lesionectomy: surgery to remove isolated brain lesions that are responsible for seizure activity.
Lobe: one of the sections of the cerebrum, the largest part of the brain. The lobes are divided into four paired sections (frontal, parietal, occipital, and temporal). The seizure focus is usually located in one of the lobes.
Lumbar puncture: a diagnostic procedure in which the fluid surrounding the spinal cord (cerebrospinal fluid) is withdrawn through a needle and examined in a lab. Also known as a spinal tap.