Neurodiagnostics is the scientific field devoted to the recording and study of electrical activity of the brain and nervous system.

Technologists record electrical activity arising from the brain, spinal cord, peripheral nerves, and motor nerve systems using a variety of techniques and instruments.

Electroencephalogram (EEG)

The Electroencephalogram (EEG) is a recording of the on-going electrical activity of the brain. EEGs assist in the diagnosis of various brain disorders and are used to evaluate the effects of head trauma or the consequences of severe infectious disease.

EEG information can help surgeons determine surgical treatment of epilepsy and can assure surgeons that the brain receives enough oxygen during surgery on the arteries. EEGs can help diagnose seizure disorders, tumors, head injuries, hemorrhages in the brain, sleep disorders, and many more illnesses.

How do I prepare for an EEG?

Patients should arrive with clean, dry hair. Do not put any oil, gel or hairspray in your hair prior to the test. If your hair is long, do not braid it or put it up. Hair extensions, hair weaves, and dreadlocks make the procedure very difficult, if not impossible.

Your physician will give you instructions on how much sleep to get the night before the test. Typically, this is between 2-5 hours.

Avoid any caffeine at least 12 hours prior to the test. This includes coffee, soda, tea and chocolate.

Your physician will instruct you on whether or not to take your medications prior to the EEG.

What is involved with an EEG?

The technologist will obtain a brief medical history before beginning the test.

The technologist will measure your head and make small marks with a soft crayon. Each electrode site will be prepped with a gritty lotion and then 26 flat metal sensors (electrodes) will be applied to your scalp with a water soluble cream.

During the test, you will be positioned in a reclining chair. It is very important that you hold as still as possible during the recording process. Any movement can obscure the brain activity being recorded.

The technologist will record your brainwaves on a computer for approximately 30 minutes. During the recording, you may be asked to breathe quickly for 3-4 minutes. You will be instructed to open and close your eyes several times. At the end of the test, a strobe light will flash at various speeds. It is okay to fall asleep during the test.

When the EEG is over, the technologist will remove the electrodes and clean any excess cream off your head with a warm washcloth. If any of the cream remains in your hair, it will wash out with regular shampoo.

How long will the test take?

An EEG takes approximately 1 hour. It takes approximately 30 minutes to apply all the electrodes, and approximately 30 minutes to record the brainwaves.

How long does it take for my doctor to receive the results?

The test will be sent to a neurologist on the same day it is performed. It usually takes 4-5 days for the report to reach the ordering physician.

Is it painful and will you have to cut my hair/shave my head?

An EEG is not painful and we do not have to cut or shave your hair. The electrodes are attached to your scalp between the hairs.

Evoked Potential (EP)

An Evoked Potential (EP) is a recording of electrical activity from the brain, spinal nerves, or sensory receptors that occurs in direct response to external stimuli. A technologist commonly performs this test during surgery on the spine to help the surgeon make sure the nerves are not damaged during the operation.

Scheduling a Test

How do I schedule a test?

Outpatient Neurodiagnostic services are provided through Boulder Community Hospital at the Mapleton Campus located at Mapleton and 4th Street. Tests require a physician’s order.

To schedule call 303-440-2095

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