Electroencephalogram (EEG)

An Electroencephalogram (EEG) is a non-invasive medical test used to evaluate the electrical activity of the brain. It is commonly used to diagnose and monitor conditions such as epilepsy, seizures, and other neurological disorders.

How it Works

The EEG test involves placing small electrodes on the scalp, typically 16-25 in number, which are connected to a machine that records the electrical activity of the brain. The electrodes detect the tiny electrical signals produced by the brain's neurons and transmit them to the machine, which amplifies and records the signals.

Types of EEG

There are several types of EEG tests, including:

• Resting EEG: This is the most common type of EEG test, where the patient sits or lies down in a relaxed state with their eyes closed.
• Sleep EEG: This test is used to evaluate brain activity during sleep and can help diagnose sleep disorders such as insomnia or sleep apnea.
• Ambulatory EEG: This test involves wearing a portable EEG device for an extended period, usually 24-48 hours, to monitor brain activity during daily activities.
• Video EEG: This test combines EEG with video recording to capture and analyze seizures or other abnormal brain activity.

Preparation and Procedure

To prepare for an EEG test, patients are typically asked to:

• Wash their hair the night before to remove any styling products
• Avoid using hair styling products on the day of the test
• Arrive at least 30 minutes before the scheduled test time
• Remove any metal objects, such as jewelry or glasses, that may interfere with the test

The EEG procedure typically takes 15-60 minutes to complete and involves:

• Placing electrodes on the scalp
• Adjusting the electrodes to ensure proper contact
• Recording brain activity while the patient is at rest or performing specific tasks, such as reading or problem-solving

Risks and Side Effects

The EEG test is generally considered safe and painless. However, some patients may experience:

• Mild discomfort or skin irritation from the electrodes
• Dizziness or lightheadedness during the test
• Seizures or other abnormal brain activity in rare cases

Interpretation of Results

The EEG results are interpreted by a qualified healthcare professional, typically a neurologist or epileptologist. The results can help diagnose and monitor conditions such as:

• Epilepsy and seizures
• Encephalitis (brain inflammation)
• Meningitis (inflammation of the membranes surrounding the brain and spinal cord)
• Brain tumors or cysts
• Stroke or cerebral vasculature disorders

The EEG results can also help monitor the effectiveness of treatment and adjust medication as needed.

Frequently Asked Questions (FAQs)

What is an Electroencephalogram (EEG)?
A test that measures electrical activity in the brain.

Why is an EEG performed?
To diagnose and monitor conditions such as seizures, epilepsy, and brain disorders.

How is an EEG performed?
By attaching electrodes to the scalp to record brain waves.

Is an EEG painful?
Typically no, but may cause mild discomfort due to electrode placement.

How long does an EEG take?
Usually 15-60 minutes, depending on the type and purpose of the test.

Do I need to prepare for an EEG?
Possibly, by washing hair and avoiding styling products or certain medications.

Can I drive after an EEG?
Generally yes, but may depend on individual circumstances and any sedation used.

What can an EEG diagnose?
Conditions such as epilepsy, seizures, encephalitis, and brain damage, among others.

Are there different types of EEGs?
Yes, including routine, sleep-deprived, and ambulatory EEGs, each with specific purposes.

Can children undergo an EEG?
Yes, EEGs can be performed on people of all ages, including infants and children.