ELECTROENCEPHALOGRAPHY

Prepared by: Roxanne Mae Birador SN

HANS BERGER a German psychiatrist (1924)

-published his first paper on the human electroencephalogram in 1929.

-placing needle electrodes under the scalp of patients who had lost some of their skull bones in surgery

With Chronic depression, he committed suicide by hanging himself, died at 68y/o

ELECTROENCEPHALOGRAM

procedure that detects electrical activity of brain using small, flat metal discs (electrodes)

attached to the scalp

The brain cells communicate via electrical impulses and are active all the time, even when

the patient is asleep.

16 to 20-25 electrodes are attach to the scalp

The activity of brain shows up as wavy lines on an EEG recording.

It is a laboratory instrument commonly used to display and analyze the waveform of electronic signals.

EEG OSCILLOSCOPE previously called an oscillograph,and informally

known as a scope

FACTORS that may INTERFERE the reading of EEG:

• Low blood sugar (hypoglycemia) caused by fasting

• Body or eye movement during the tests (but this will rarely, if ever, significantly interfere with the interpretation of the test)

• Lights, especially bright or flashing ones

• Certain medications, such as sedatives

• Oily hair or the presence of hair spray

• Drinks containing caffeine, such as coffee, cola, and tea

(these drinks can occasionally alter the EEG results, this almost never

interferes significantly with the interpretation of the test)

TYPES OF ELECTROENCEPHALOGRAPHY

Routine EEG Tests

Ambulatory EEG Tests

Sleep EEG Tests

Sleep-Deprived EEG Tests

EEG is one of the main diagnostic tests for EPILEPSY

If the patient are being evaluated for a sleep disorder, the EEG may be performed while he is asleep.

Comatose patient

Dementia

INDICATIONS

Encephalitis

Stroke

Brain tumorBrain Injury

NOTE:An EEG can't measure intelligence

or detect mental illness.

RISKS

EEGs are safe and painless. Sometimes seizures are intentionally triggered in people with epilepsy during the test, but appropriate medical care is provided if

needed.

Scalp irritation/ redness may also occur

Is Electroencephalogram can be also a

LIE-DETECTOR TEST?

Year 1999, Dr. Lawrence Farwell conducts a Brain Fingerprinting test (EEG TEST) on serial killer JB Grinder.

Convicted as a serial rapist and murderer

POLYGRAPH

PREPARATION

Wash hair night before or the day of the test, but don't use

any conditioners, hair creams, sprays or styling gels.

Hair products can make it harder for the sticky patches that hold the electrodes to adhere to patient’s scalp.

Drugs which may interfere with the EEG tracing, such

as tranquillisers, stimulants and

anticonvulsants, may be withheld for about 24 hours before the test.

Some dietary stimulants, such as tea and coffee, may also be withheld for 8 to 12

hours before an EEG.

Avoid fasting the night before or the day of the procedure. Low blood sugar may

influence the results.

If the EEG is to be performed during sleep;

ADULTS may not be allowed to sleep more than 4 or 5 hours the night before the test

CHILDREN may not be allowed to sleep for more than 5 to 7 hours the night before.

DURING THE TEST

A technician measures head and marks scalp with a special pencil, to indicate where to attach the electrodes.

A technician attaches flat metal discs (electrodes) to your scalp using a special adhesive. Sometimes, an elastic cap fitted with electrodes is used instead.

Once the electrodes are in place, an EEG typically takes up to 60 minutes. If the patient

need to sleep for the test, it may take up to three hours.

At various times, the technician may ask the patient to open and close his eyes, perform a few simple calculations, read a paragraph, look at a picture,

breathe deeply (hyperventilate) for a few minutes, or look at a flashing light.

Video is frequently recorded during the EEG. The body motions are captured by a video

camera while the EEG simultaneously records brain waves. This combined recording may help

the doctor diagnose and treat patient’s condition.

REFERENCES:

http://www.mayoclinic.org/testsprocedures/eeg/basics/definition/prc-20014093

http://www.nursingtimes.net/electroencephalography/206192.fullarticle

http://www.emedicinehealth.com/electroencephalography_eeg/page4_em.htm

http://www.discoveriesinmedicine.com/Com-En/Electroencephalogram-EEG.html

http://www.hopkinsmedicine.org/healthlibrary/test_procedures/neurological/electroencephalogram_eeg_92,p07655/