What is epilepsy?
Epilepsy is a brain disorder characterized by recurrent seizures. A seizure is a brief alteration of consciousness (level of awareness), muscle control, behavior or sensory perception. Seizures can last a few seconds to several minutes.
During a seizure, brain cells behave abnormally and show unusual repeated electrical discharges. This often begins within a small cluster of abnormal nerve cells and spreads to involve normal cells in other areas of the brain.
Comprehensive Epilepsy Program
The UC Davis Medical Center’s Comprehensive Epilepsy Program is a leading program for the medical and surgical management of complex epileptic disorders. In conjunction with the program, a wide array of services are available:
The program provides a state-of-the-art, three-bed inpatient epilepsy monitoring unit, high-resolution magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and positron emission tomography (PET).
Research facilities in the basic neurosciences are housed at the Center for Neuroscience on the Davis campus.
Medically intractable seizures
Patients with medically intractable seizures are referred to the Comprehensive Epilepsy Program. The patients are evaluated to determine whether the current therapeutic regime is adequate and appropriate. Staff examines anticonvulsant drug levels and dosage schedules, performs neuropsychological tests, performs baseline electrographic studies and monitors and documents the response to medications at various dosages.
Surgical therapy for epilepsy
One goal of our intensive evaluation is to identify patients who would benefit from surgical therapy. Based on a preliminary evaluation, a patient can be admitted to the hospital for video electroencephalogram (EEG) monitoring to document the site of an epileptogenic lesion. Patients determined to be candidates for surgery undergo angiography and Wada testing to establish the lateralization of language.
The Wada test consists of the injection of sodium amytal into the arteries carrying blood to the brain in order to anesthetize half the brain for about one minute. This allows the physician to determine the impact of the intended surgical removal on language. The procedure is done as an outpatient under local anesthesia by a neuroradiologist who places a small catheter in an artery in the groin. The neuropsychologist and neurologist participate in the testing of the patient's language and memory during the test.
In selected cases, depth or subdural grid electrodes are implanted on the surface of the brain by a surgical procedure to further localize the area of the brain from which the seizures are arising. Intra-operative electrocorticography and depth recordings are also used to further delineate the epileptogenic cortical focus.
Advanced diagnostics for the evaluation of epilepsy
Single photon emission computed tomography (SPECT) and functional magnetic resonance imaging (fMRI) studies can be done in appropriate patients to delineate the area of the brain from which the seizures are arising. These procedures are done prior to the more invasive studies discussed above. Patients are followed in the clinic for at least two years after surgery. Those patients not considered candidates for surgery are also followed for extended periods and are often enrolled in protocols to study new pharmaceuticals.
Also assisting in the evaluation of epilepsy is the Clinical Neurophysiology Laboratory. This laboratory performs more than 3,000 procedures annually and include routine studies as well as specialized procedures related to epilepsy and sleep disorders.