Ambulatory EEG

Prolonged EEG: It is used in cases in which a routine EEG does not provide the necessary information to make a medical decision. It could go from a few hours to several days. Most of the prolonged EEG devices have an “event button” (a button that the patient is asked to press every time they feel something unusual) for the patient to mark when an episode occurs.  This way when the test is complete, the doctor will know what times to pay special attention when looking over the readings.

This test is indicated when:
The diagnosis of epilepsy is not clear (to diagnose epilepsy versus non-epileptic events)
The diagnosis of epilepsy is clear, but the specific type of epilepsy is not known
The patient is not responding to treatment
Epilepsy surgery is being considered

Ambulatory EEG: is a type of prolonged EEG. The patient is usually connected to the device in the physician’s office or at the hospital outpatient facility. The patient goes home with the electrodes covered by a head wrapping and carries a “recorder” that tapes and stores the EEG information. When the study is done, the recorder is returned by the patient and the information is analyzed by the doctor.

Advantages:
• There is no need for hospitalization and the patient is in his/her natural environment.

Disadvantage:
• In the event that an episode happens, it is not filmed on video.
• If there is a technical problem, the entire study could be lost since the technician will have no way to detect it until the recorder is returned.
• Medications cannot be decreased at home since it is very risky