An overview of Electroencephalogram (EEG)
An electroencephalogram (EEG) is a diagnostic test that measures electrical activity in the brain using small, metal discs (electrodes) attached to the scalp. It helps diagnose brain disorders, especially epilepsy, as well as conditions like brain tumors, brain damage, encephalopathy, sleep disorders, inflammation of the brain, and others. During an EEG, the electrodes record brain waves, and a technician might ask the patient to perform simple tasks or sleep to obtain a more accurate reading. The test is painless and typically takes 20-40 minutes.
What is Electroencephalogram (EEG) used for?
An electroencephalogram (EEG) is a diagnostic test used to measure electrical activity in the brain. It is primarily used to diagnose and assess various brain disorders, particularly epilepsy and seizure disorders. Additionally, EEGs can help diagnose or treat conditions such as brain tumors, brain damage from head injury, encephalopathy, sleep disorders, herpes encephalitis, stroke, and Creutzfeldt-Jakob disease. EEGs can be performed in an office or hospital setting, with ambulatory EEGs allowing for longer monitoring outside those settings. During an EEG, electrodes are attached to the scalp, and the test typically takes between 20 and 40 minutes.
How to prepare for Electroencephalogram (EEG)?
Before an EEG test, patients generally need to:
- Take their usual medications unless instructed otherwise.
- Wash their hair the night before or the day of the test, avoiding conditioners, hair creams, sprays, or styling gels. These products can interfere with the adhesion of electrodes to the scalp.
- Refrain from eating or drinking anything for a few hours before the test, as instructed by the healthcare provider.
- Avoid applying lotions, oils, or makeup on the day of the test, as these substances can interfere with the electrodes' adhesion.
- Follow any other specific precautions or instructions provided by the healthcare provider. It is important to follow these guidelines to ensure accurate results and minimize any potential interference with the EEG test.
How is Electroencephalogram (EEG) conducted?
An electroencephalogram (EEG) test is conducted by attaching small metal discs (electrodes) to the scalp using a special adhesive. The electrodes measure electrical activity in the brain, which is recorded on computer equipment. During the test, the person being tested may be asked to perform various tasks such as opening and closing their eyes, performing calculations, reading a paragraph, or looking at a picture. The test typically takes between 20 and 40 minutes, and a video recording is also made to help diagnose and treat conditions. It is safe and painless, and the person can expect little to no discomfort during the test.
How are Electroencephalogram (EEG) results reported?
EEG results are reported by doctors trained to analyze EEGs, who interpret the recording and send the results to the doctor who ordered the EEG. Typically, you'll need to schedule an office appointment to discuss the results of the test. It's recommended to bring along a family member or friend to the appointment to help you remember the information you're given. After the appointment, you can ask your doctor questions, such as:
- Based on the results, what are my next steps?
- What follow-up, if any, do I need?
- Are there factors that might have affected the results of this test in some way?
- Will I need to repeat the test?
Understanding the report
An EEG test measures electrical activity in the brain and is analyzed by doctors trained to interpret EEG recordings. They will send the results to the doctor who ordered the test. It's essential to schedule an office appointment to discuss the results and any necessary follow-up actions. You may want to bring a family member or friend to the appointment for support and to help you remember the information provided. Some questions to ask your doctor include:
- Based on the results, what are my next steps?
- What follow-up, if any, do I need?
- Are there factors that might have affected the results of this test in some way?
- Will I need to repeat the test?