Patients with complex epilepsy or unexplained seizure disorders come to the Comprehensive Epilepsy Program for a definitive diagnosis and tailored treatment plan. Due to physical properties of epileptic tissue, arriving at a clear picture of a patient's underlying condition often requires a combination of advanced diagnostic methods. Unlike tumor cells, brain cells that cause epilepsy can look just like normal brain tissue. The difference lies in their abnormal electrical behavior. Through a combination of brain activity monitoring, imaging and mapping techniques, physicians can locate the brain tissue causing epilepsy and identify its location in relation to vital brain functions. The tools also enable doctors to determine other seizure causes when they are not associated with epileptic tissue.

Sutter's Comprehensive Epilepsy Program offers the most advanced tools available to determine the nature of seizure disorders and define epilepsy tissue. Sophisticated equipment combined with skilled medical and technical experts enable doctors to pinpoint the site and severity of seizure activity in patients-the fundamental first step to establishing a treatment plan. Such technologies allow specialists to, information vital to selecting the most effective treatment options. The program accepts referrals for long-term video EEG monitoring (LTM) and consultation.

Diagnostic tools available include:

• Adult and pediatric epilepsy monitoring units (EMUs)


• EEG testing, including routine, long-term video monitoring and ambulatory EEG


• Wada testing


• Imaging studies, including PET, MRI and SPECT scanning


• Electrocorticography mapping


• Functional cortical mapping

Recently, Sutter Neurosurgeon Edie Zusman, M.D., has been part of a collaborative effort through the National Science Foundation, Center for Biophotonics that may have identified a metabolic label that causes epileptic cells to light up, clearly marking their difference. Through still in preliminary research, a visible marker would greatly speed doctors' ability to identify epileptic cells and may eventually lead to new treatments.

Adult and Pediatric Epilepsy Monitoring Units (EMUs)

Just as every patient is unique, so are the causes, manifestations, frequency and severity of each patient's seizures. Epileptic seizures do not happen on command and may be separated by minutes, hours, days, or longer. In addition, visible signs can vary widely from a slightly dazed look to extreme convulsions. Seizures may also affect different areas of physical function, which the patient may or may not realize and be able to report.

The epilepsy monitoring unit (EMU) provides valuable insight into the exact nature of a patient's seizures and can verify if epilepsy is the cause of seizures. Sutter's two dedicated EMUs feature five beds for adults and two beds for children, featuring the latest testing and monitoring equipment.

Patients generally quit taking any antiepileptic drugs prior to be admitted to the EMU so that doctors can see the patients' natural epilepsy patterns. In some cases, patients may need to stay awake longer than normal to help trigger seizures. During their stay in the unit, patients are monitored by video and through a continuous electroencephalogram (EEG) so that doctors can see what takes place visibly and through brain wave recordings during a seizure. The EEG equipment used allows the patient to move around freely during their stay in the unit.

Additional information on video EEG monitoring can be found under exams and tests in the epilepsy topic of our Health Information library and from the National Institute of Health's National Institute of Neurological Disorders and Stroke (www.ninds.nih.gov) and the Epilepsy Foundation (www.epilepsyfoundation.org).

Electroencephalogram (EEG) Testing

An electroencephalogram or EEG is the most common test doctors use to screen for epilepsy. During an EEG, sensors attached to the patient's scalp are connected to a computer. The highly sensitive electrodes transmit brain wave information recorded as wavy lines on the computer screen. Because epilepsy is a condition caused by electrical disturbances, the line patterns recorded during a seizure appear different than normal brain wave patterns, helping doctors to better understand that nature of a patient's seizures. EEGs can be performed while the patient is lying down or moving about (ambulatory) and may be used in conjunction with other tests, as in the epilepsy monitoring unit. Though helpful, EEGs do not always provide clear-cut answers and are often supplemented by additional tests.

Wada Testing

The brain is divided into two hemispheres that work together, with certain functions typically stronger on one side than the other. Prior to deciding if a patient with intractable seizures is a good candidate for surgery, doctors test the function of each side of the brain to determine if surgery on the epileptic tissue will affect the patient's speech, language processing and memory. The Wada test, named after the doctor who developed it, simulates epilepsy surgery by putting one side of the brain to sleep for a short time and leaving the other side awake and functioning. With one side of the brain asleep, patients are given a series of tests that demonstrate speech and memory skills. The test is repeated on the other side to give doctors insight on where speech and memory reside in relation to the epileptic tissue. The Wada test helps doctors determine if a patient is a good candidate for epilepsy surgery or if the epileptic tissue is located in a critical area of the brain.

Imaging Studies

As part of the Sutter Health system and Sutter Neuroscience Institute, patients of the Comprehensive Epilepsy Program have access to sophisticated imaging equipment that includes positron emission tomography (PET), computed tomography (CT), magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) scanning. MRI and CT scans help doctors see the structure of the brain and any abnormal tissue, while PET and SPECT scanning helps doctors see the blood flow and metabolic function of the brain. In complex epilepsy, imaging tests help doctors locate the area of the brain causing seizures, which is useful in determining the best course of treatment.

Additional information on imaging studies can be found under exams and tests in the epilepsy topic of our Health Information library and from the National Institute of Health's National Institute of Neurological Disorders and Stroke (www.ninds.nih.gov) and the Epilepsy Foundation (www.epilepsyfoundation.org).

Electrocorticography Mapping

Though epileptic tissue may appear the same as normal brain tissue, it behaves differently, sending out spikes of electrical impulses. Using instruments that detect the spikes, doctors can locate and define the seizure focus-the exact region of the brain from which seizures originate. To do this, doctors use a process called electrocorticography to outline the area by showing where abnormal electrical activity is present and where it stops.

Similar to electroencephalogram (EEG) testing that uses sensors placed on the scalp to record the brain's electrical activity, electrocorticography testing uses sensors placed on brain's surface to get a more precise recording and to determine specific locations of electrical activity. Epileptic regions of the brain create electrical spikes, which the computer records. Areas of high epileptic activity show pronounced and consistent spiking, while areas of normal function show no, minor or intermittent spiking. The difference in electrical activity allows doctors to clearly define the exact location and margins surrounding epileptic to create a virtual picture of abnormal tissue.

Functional Cortical Mapping

Before surgeons remove epileptic tissue, they first test the different sections of the targeted tissue to determine how important each area is to the patient's memory and ability to speak and process language. Areas determined to be essential memory and language sites are avoided during surgery, so that the patient retains critical abilities.

During mapping, designated areas of the brain are stimulated using a mild electrical current. While the area is stimulated, the patient is asked to identify pictures of common items, describe an item, or answer other questions that let doctors know what the stimulated section does. If the patient has difficulty answering the questions or is confused, the region stimulated is deemed to be essential and is avoided in surgery.