How long eeg take

What are the different types of EEGs? Routine EEG: may take only 20 to 30 minutes, usually without video but this can easily be added.

The most common are photic stimulation fast, flashing lights or patterns , hyperventilation very quick breathing , and sleep deprivation staying up late the night before.

Prolonged EEG: 1 to 2 hours may be done with or without video. The length of recording can vary and it may be done with or without video. EEG-video monitoring: this is usually assumed to be inpatient and prolonged done over a number of days. Long-term monitoring: this term is confusing because it only refers to length of testing. This term is often used to mean the same thing as EEG-video monitoring. Epilepsy monitoring and EEG monitoring are general terms that specify neither what is monitored video or not nor for how long , and probably should not be used.

The electroencephalogram EEG is a medical test used to measure the electrical activity of the brain, via electrodes applied to your scalp. This procedure is completely painless and can be performed without shaving any of your hair. EEG can help diagnose a number of conditions, including epilepsy, sleep disorders and brain tumours.

Another name for EEG is brain wave test. Normal brain waves occur at a rate of up to 30 per second, but in someone with epilepsy, for example, the EEG may show bursts of abnormal discharges in the form of spikes and sharp wave patterns. Suspected epilepsy is the most common reason for an EEG. Other conditions that may be diagnosed with the aid of an EEG include:. An abnormal EEG doesn't automatically mean that you, for example, have epilepsy.

The EEGs of babies and young children can often record irregular patterns that don't mean anything, or the irregularities may flag previously diagnosed neurological conditions such as cerebral palsy.

On the other hand, a normal EEG doesn't rule out epilepsy either. Sometimes, a person with epilepsy will only display abnormal brain waves during a seizure. Your hair must be thoroughly clean, but most importantly dry. A number of electrodes are applied to your scalp generally between 8 and 23, depending on the condition under investigation.

A gel may be applied to help the electrodes to stick firmly in place and improve recordings. You will need to lie quietly to avoid any electrical interference from muscle contractions. Sometimes, you may be asked by the doctor to open and close your eyes and to breathe heavily.

Lights may be flashed before your eyes. An EEG usually takes from 30 to 60 minutes to complete. An EEG might also be helpful for diagnosing or treating the following disorders:. An EEG might also be used to confirm brain death in someone in a persistent coma.

A continuous EEG is used to help find the right level of anesthesia for someone in a medically induced coma. 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. During an EEG , flat metal discs electrodes are attached to your scalp. In a high-density EEG , shown here, the electrodes are closely spaced together.

The electrodes are connected to the EEG machine with wires. Some people wear an elastic cap fitted with electrodes, instead of having the adhesive applied to their scalps. You'll feel little or no discomfort during an EEG. The electrodes don't transmit any sensations. They just record your brain waves. Here are some things you can expect to happen during an EEG :. A technician attaches discs electrodes to your scalp using a special adhesive.

Sometimes, an elastic cap fitted with electrodes is used instead. How is the test done? How long does the test take? What are the risks of an electroencephalogram EEG? What happens after the test?

When should you call for help? Where can you learn more? Top of the page. What is it? Tell your doctor ALL the medicines and natural health products you take.

Some may increase the risk of problems during your test. Your doctor will tell you if you should stop taking any of them before the test and how soon to do it. Do not eat or drink anything with caffeine in it for 12 hours before the test. This includes cola, energy drinks, and chocolate. Shampoo your hair and rinse with clear water the evening before or the morning of the test.

Do not put any hair conditioner or oil on after you wash your hair. Your doctor may ask you not to sleep the night before the test or to sleep for only about 4 or 5 hours. This is because some types of brain activity can only be seen if you are asleep.

If your doctor asks you to get less sleep than normal, plan to have someone drive you to and from the test.