Frequently Asked Questions

What is epilepsy monitoring for?

Epilepsy monitoring is the use of simultaneous video-electroencephalography (EEG). Performed on an inpatient basis, video-EEG provides brainwave recordings simultaneous with videotaping of the patient. This technique has been called long-term monitoring. Epilepsy monitoring takes many forms including: prolonged standard EEG, ambulatory EEG monitoring and simultaneous video-EEG monitoring.

Long-term monitoring has several potential uses:
It can establish the diagnosis of epilepsy, separating it from other intermittent non-epileptic events that mimic epilepsy. In most epilepsy centers, about 1 in 4 patients recorded with seizure-like events that are unresponsive to medication do not have epilepsy.

It can be used in differentiation of seizure types. Seizures may not respond to medication for primary generalized epilepsy if these seizures are actually secondarily generalized seizures. This problem arises typically in childhood where complex partial seizures and absence may be mistaken. For more information, click on Epilepsy or common types of Epilepsy.

Long-term monitoring localizes the brain region of seizure onset. The area of seizure origin must be defined to provide a surgical treatment for epilepsy. The correlation of the video appearance with the EEG provides part of that definition.

Video-EEG monitoring quantifies seizure frequency. Routinely in epilepsy care, determining an absolute seizure frequency is unnecessary. Video-EEG monitoring can be used to count seizures when such accuracy is demanded. The use of new anti-epileptic medications may involve administering doses on an inpatient basis with seizures verified by video-EEG to show the effectiveness of the drug.

Why are both the video and EEG monitoring needed?

The simultaneous use of video and EEG is needed to verify when seizures begin and what they look like. Ambulatory monitoring provides a recording of EEG that is focused at the time patients report in a seizure diary. An event marker pushed after the fact makes the correlation between the patient's event and the EEG. This correlation is loose enough that a random EEG discharge could be misinterpreted as part of a seizure depending on when an event was signaled. The patient who may be unaware of the nature of the event also makes the report of the event. When possible, it is desirable to record and treat the seizures disabling the patient.

Patients with multiple seizure types may find it impossible to record which type occurred. The video recording eliminates classification difficulties by allowing videotape review by patient family members familiar with the patient's seizure types.

What happens during a patient's admission for monitoring?

The patient is admitted to the Regional Epilepsy Center on a Monday morning. Electrode sensors are attached to the patient's scalp. The patient is then escorted to the 6th Floor to a designated monitoring room and connected to the monitoring equipment. The equipment receives the EEG and incorporates digitalized EEG with the video image.

An online computer constantly monitors EEG changes. When a seizure has occurred, the computer records the time and a brief EEG sample of that event.

Patient medication is tapered by approximately 33% each day and therefore shortens the monitoring time.

Prior to admission, neuropsychological tests are given to the patient and scored. In addition, computed tomography (CT) and magnetic resonance imaging (MRI) are ordered or reviewed prior to admission. Once the evaluation is complete, a neurosurgical consultation is obtained. The neuropsychologist, neurologist, and neurosurgeon review the patient's tests to decide if there is an isolated seizure focus to indicate if surgery or more testing is necessary. The patient is informed of the results either at discharge or in a subsequent appointment following discharge. Contact is maintained with the referring physician during and following the hospitalization.