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"How are EEGs used to diagnose epilepsy?"

ZocdocAnswersHow are EEGs used to diagnose epilepsy?


In the pas I have shown symptoms of epilepsy. How does an EEG prove I have it once and for all.


An electroencephalogram (EEG) is a procedure in which a neurologist measures and views your brain waves in order to help diagnose brain diseases. Epilepsy is a syndrome which causes seizures to occur in the brain. You are correct in that an EEG is used to diagnose seizures, and therefore epilepsy.

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However, it is not quite that simple. An EEG can only detect a seizure when seizure like waves, or seizures themselves are occurring in the brain. A typical EEG only measures brain activity for 1-2 hours up to 24 hours (if you are in the hospital). If your brain is quiet of seizure like activity during this time, the EEG will be unable to diagnose a seizure. This is why so many people that have had a seizure don't officially get diagnosed with epilepsy by EEG. However, it is still very worth while to have an EEG if you have had a seizure. I suggest that you schedule an appointment with your neurologist. He or she can take a history of your seizures and perform a comprehensive neurological exam. If it is seen as necessary, your neurologist will have you come back for an outpatient EEG to look for any seizure activity in your brain.

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