How long after a seizure can an EEG detect it?

EEG: If performed within 24-48 hours of a first seizure, EEG shows substantial abnormalities in about 70% of cases. The yield may be lower with longer delays after the seizure.

What happens if you don’t have a seizure during an EEG?

A normal EEG does not mean that you did not have a seizure. Approximately one-half of all EEGs done for patients with seizures are interpreted as normal. Even someone who has seizures every week can have a normal EEG test. This is because the EEG only shows brain activity during the time of the test.

Can doctors tell if you’ve had a seizure?

Your primary care doctor may do some tests. If your doctor thinks you’ve had a seizure, she will probably refer you to a neurologist (“ner-AH-luh-gist”). A neurologist is a doctor with special training in disorders of the brain, including epilepsy.

Does a normal EEG rule out epilepsy?

An EEG can usually show if you are having a seizure at the time of the test, but it can’t show what happens to your brain at any other time. So even though your test results might not show any unusual activity it does not rule out having epilepsy.

Can a neurologist tell if you’ve had a seizure?

These studies are interpreted, or “read,” by a trained neurologist. Clinicians can find evidence of abnormal electrical activity in the brain and figure out the type or types of seizures a patient is having, as well as the origin(s), by measuring brain waves over minutes to a couple of hours.

Can an EEG be misread?

The consequences of misreading EEGs are many. First, it may delay arriving at the correct diagnosis. Once a patient is ‘labeled’ with a diagnosis, it is difficult to undo it. It requires obtaining the original EEG and reinterpreting it.

Can anxiety cause abnormal EEG?

Background. Since the 1980s, a high EEG abnormality rate has been reported for patients with panic disorder.

Can a EEG be wrong?

Yes, EEG can be bad for you. The consequences of being misdiagnosed with epilepsy are obvious and serious [9]. When the diagnosis is based largely on an abnormal EEG, no amount of subsequent normal EEGs will ‘cancel’ the previous abnormal one, and the wrong diagnosis is very difficult to undo.