The Neurological Diagnosis Institute

Electroencephalogram (EEG) Test

The EEG test is a procedure in which electrodes placed on the scalp measure and assess the electrical activity of the brain (similar to an ECG test performed on the chest to assess heart activity). The test is non-invasive and painless. The technician attaches electrodes to the head with a special paste, and the recording is transmitted to a dedicated computer.

EEG testing is mainly used to suspect and monitor seizures and epilepsy, but it is also used to assess brain function in cases of cognitive disorders, encephalitis, and various diseases that affect brain function.

Types of Tests Performed at the Institute (including required preparation procedures):

• EEG Test in Wakefulness: A 20-30 minute test that describes the brain's activity during wakefulness, including stimuli such as hyperventilation or flashing light.

• EEG Test During Sleep: A more sensitive test performed after sleep deprivation to allow falling asleep and observe brain activity during sleep. The test lasts approximately 60 minutes.

• Video EEG Test: Video-EEG monitoring is the optimal test for evaluating suspected seizures, their origin, and type. The test combines brain electrical activity recording through electrodes placed on the scalp and video recording in full synchronization.

  Test Purpose: Diagnosis and monitoring of epileptic seizures and other conditions that may mimic seizures, such as sleep disorders, movement disorders, cardiac origin disturbances, and behavioral changes. The test helps differentiate between these events and epilepsy, which aids in choosing appropriate treatment and avoiding unsuitable treatments that may cause side effects or harm. In epilepsy monitoring, the test helps characterize the type of epilepsy, locate the epileptic focus for possible surgical consideration, and assess seizure frequency. Monitoring during the night can assist in diagnosing and identifying epilepsy types that manifest primarily from deep sleep, which might not be detected in light sleep during a sleep deprivation test.

How is the Video EEG Test Performed? Hospitalization in the neurology department is required for the test. Continuous EEG monitoring is conducted by attaching electrodes to the scalp, secured with a special paste and a head wrap. The patient is provided with a small bag containing the device to which the electrodes are connected. A video camera and microphone operate in the room 24/7 to monitor and record symptoms of seizures or other clinical events occurring during the monitoring. It is essential to have visual documentation for the entire test, except for bathroom breaks. A special button is used to mark events if they correspond to specific symptoms being investigated. The minimum monitoring period is two days. In special cases, after consultation with the department team, extended hospitalization may occur, involving medication adjustments and the induction of epileptic seizures.