Examination: I have to pass an electroencephalogram

Examination: I have to pass an electroencephalogram

How's it going ?

At the hospital or the neurologist's office, you sit in a comfortable chair. A nurse puts electrodes on your head, held with a net "helmet". The recording starts with your eyes closed, then you have to open and close them several times. You will also be asked to breathe very hard for four minutes: this hyperpnea excites the brain to better identify any anomalies. Then expect some light stimulation with flashes at different frequencies (sort of strobe). The recording lasts twenty minutes and the total examination about half an hour. If needed, a longer recording can be done during sleep to complete.

It's used for ?

The electroencephalogram (EEG) measures the activity of the brain to detect possible malfunctions. Its main indication is a suspicion of epilepsy. The risk increases with age even if it has never been done before, and it may be related, for example, to an unnoticed stroke. It does not always translate into a crisis of convulsions but sometimes by absences, fluctuating memory disorders, a state of confusion. In general, an EEG is prescribed as soon as there are unexplained neurological disorders. It can also help to detect encephalopathy (inflammatory disease of infectious or drug origin).

Not even scared, not bad

The examination is completely painless. You have to move as little as you can and try to relax, because stress causes contractions in the muscles of the head that can skew the results. Hyperpnea is not practiced in cases of large cardiac or pulmonary pathology (such as respiratory failure).

What preparation?

Nothing to do before, only bring your old tracks if you have already done an EEG. Also report any sores or irritation on the scalp.

And after ?

The recording is usually interpreted by a neurologist in the minutes following the examination and a report is received. Sometimes the consultation can take place in the wake. In some cases, the EEG must be completed (by brain MRI, lumbar puncture ...) to confirm the diagnosis.

Thanks to Dr. Philippe Derambure, neurologist at Lille University Hospital.

Examination: I have to pass an electroencephalogram