Routine EEG

The routine EEG is the most common test for epilepsy. The actual recording usually lasts only 20 to 40 minutes, and the same amount of time is generally needed to prepare for it. 

Routine EEG 

The routine EEG is the most common test for epilepsy. The Archer Medical EEG Technologist first measures the patient’s head so that the electrodes, which are small, metal, cup-shaped disks attached to wires, can be placed in the correct position. A wax crayon, which can be easily washed off later, is used to mark the points on the scalp. Next, the Archer Medical EEG Technologist applies the electrodes, usually using a paste that holds them in place for up to several hours. The Archer Medical EEG Technologist often scrubs each position on the scalp with a mildly abrasive cream before applying the electrodes. This will help improve the quality of the recording.

The electrodes only record the brain waves. They do not stimulate the head with electricity, and pose no danger to the patient. The EEG equipment then digitally records the brain waves as a series of waveforms called traces. 

During the EEG: What to Expect

The patient may fall asleep briefly during a routine EEG, because the room is quiet and often dimly lit, which is ideal, because an EEG obtained during both wakefulness and sleep may provide extra information. During the EEG, the Archer Medical EEG Technologist will ask patients to open and close their eyes several times, may shine flashing lights into their eyes (photic stimulation), or may ask them to breathe rapidly or deeply (hyperventilation). Patients who have a medical problem, such as asthma or heart disease, which makes it unsafe to hyperventilate, should tell the Archer Medical EEG Technologist at the start of the EEG. Similarly, a pregnant woman usually should not undergo hyperventilation or photic stimulation and should make sure to tell the Archer Medical EEG Technologist that she is pregnant at the start of the test. 

How Long Does it Take?

The actual recording usually lasts only 20 to 40 minutes, and the same amount of time is generally needed to prepare for it. Thus, the routine EEG procedure usually takes 1 to 1.5 hours. The test is performed by an EEG Archer Medical EEG Technologist. The patient can help by washing his or her hair the night or morning before the test, but should avoid using conditioners, hair creams, sprays, or styling gels. 

After the EEG: What to Expect

After the EEG recording is done, the Archer Medical EEG Technologist will remove the electrodes from the patient’s scalp, and the patient is free to go home and wash the paste out of his or her hair. The paste is easily washed off. The doctor usually reads the EEG after the patient has left.