What is an EEG?

An electroencephalogram (EEG) is a test to detect problems in the electrical activity of the brain.

 

How is a Routine EEG Test Performed?

Brain cells communicate by producing tiny electrical impulses.  In an EEG, electrodes are placed on the scalp over multiple areas of the brain to detect and record patterns of electrical activity and check for abnormalities.

The test is performed by an EEG technician in a specially designed room that may be in your health care provider's office or at a hospital.  You will be asked to lie on your back on a table or in a reclining chair.

The technician will apply between 16 and 25 flat metal discs (electrodes) in different positions on your scalp.  The discs are held in place with a sticky paste.  The electrodes are connected by wires to an amplifier and a recording machine.

The recording machine converts the electrical signals into a series of wavy lines that are drawn onto a moving piece of graph paper.  You will need to lie still with your eyes closed because any movement can alter the results.

You may be asked to do certain things during the recording, such as breathe deeply and rapidly for several minutes or look at a bright flickering light.

 

How to Prepare for the Test?

You will need to wash your hair the night before the test.  Do not use any oils, sprays, or conditioner on your hair before this test.

Your health care provider may want you to stop taking certain medications before the test.  Do not change or stop medications without first talking to your health care provider.

You should avoid all foods containing caffeine for 8 hours before the test.

Sometimes it is necessary to sleep during the test, so you may be asked to reduce your sleep time the night before.

 

How the Test Will Feel?

This test causes no discomfort.  Although having electrodes pasted onto your skin may feel strange, they only record activity and do not produce any sensation.  In rare cases some skin irritation may occur.

 

Why the Test is Performed?

EEG is used to help diagnose the presence and type of seizure disorders, to look for causes of confusion, and to evaluate head injuries, tumors, infections, degenerative diseases, and metabolic disturbances that affect the brain.

It is also used to evaluate sleep disorders and to investigate periods of unconsciousness.  The EEG may be done to confirm brain death in a comatose patient.

EEG cannot be used to measure intelligence or diagnose mental illness.

 

What is a Video Ambulatory EEG?

Video Ambulatory EEG is considered to be the Gold Standard for EEG testing.  This allows the doctor to see any kind of events that you may have while you are conducting some of your normal daily activities. The neurologist will also get a better understanding of what might be happening at night while you sleep.  The ambulatory EEG device will be worn for a specific amount of time that your neurologist believes will give him/her the best chance to find what they are looking for, usually 72 hours in most cases.

• You will still have all the same electrodes that you had for your routine EEG except this time they will be held on using special glue that is made specifically for this type of medical procedure.
• You will want to wear a shirt that opens in the front so that you will be able to undress easily at night time.
• You will not be able to shower from the time you get hooked up until you get disconnected so it is wise to shower ahead of time with plenty of time so that your hair is completely dry before the set up is started. Do not use any hair gels, oils or mousse before your appointment as this will interfere with the electrodes.
• You will be given a pushbutton that you will need to press anytime you have any kind of event, headache, or confusion episodes.
• You will also have a daily diary that you will need to fill out with certain activities that you normally do throughout the day such as eating, taking meds, sleeping or napping. The more accurate you are in filling out this diary, the easier it will be for your doctor to assess your study.
• At the end of the study the electrodes will be removed from your head using an adhesive remover so the electrodes come out of the hair easily and without any damage to your hair or scalp.

 

What will the EEG Technologist do? 

Step #1 - Measure the Scalp

 

Step #2 - Mark the Scalp with a Wax Pencil

 

Step #3 - Apply electrodes with glue, gauze, and air pump

 

Step #4 - Bundle wires behind head in a pony-tail

 

Step #5 - Strategically place tape to further secure the wires

 

Step #6 - Calibrate the system and provide personalized instruction

 

Step #7 - Everything is done. EEG is being recorded and you are mobile.

 

Why is my physician ordering a Video Ambulatory EEG study?

A picture is worth a thousand words,… and the same is true when someone is experiencing blackouts, suspected seizures, or spells.  In order for your physician to provide you with the best specialized care, he/she has ordered Video EEG that will allow viewing of the brainwave activity and a time-locked video/audio recording simultaneously.  When you are experiencing any events during the monitoring, they will be captured for review by the physician.

 

Will my family members or spouse be video taped?

If one of your family members happens to walk in front of one of the video cameras, they will be on the video briefly.  But, the physician is only interested in seeing you, the patient, on video when there are clinically significant events occurring.  So, even if your family member were to walk in front of one of the cameras, it would be very unlikely that the physician would ever see that particular portion of the video tape. The video and audio recording is continuous, but will be analyzed and edited by powerful analysis software so that only portions that require the physician’s attention will be viewed.

 

What will be setup in my home, and what areas will be recorded on the camera?

There are two separate video recording tripods setup.  One will be positioned in the bedroom and aimed at the side of the bed where you will be sleeping, so that your spouse will be excluded from the camera view. The second recording tripod will be positioned in the living room, or another comparable area as you designate, where you spend a significant amount of time.  The camera view is limited to a chair or couch where you will be the majority of the time while undergoing monitoring.  All other areas of the living room or bedroom will not ever be on the video recording. 

 

Who will be viewing the video portion of the test?

The only person who will actually be reviewing your Video EEG is the physician who will be providing you with the interpretation.  The physician will only view the video when there are clinically significant events noted on the brainwaves being recorded from your scalp.