Diagnostic tests in epilepsy

• EEG
• MRI brain
• CT brain- plain and contrast
• Positron emission tomography- PET
• X-ray skull
• Complete blood test  

Electroencephalogram- EEG

Normal EEG characters

• In adults who are awake, the EEG shows mostly alpha waves and beta waves.
• The two sides of the brain show similar patterns of electrical activity.
• There are no abnormal bursts of electrical activity and no slow brain waves on the EEG tracing.
• If flashing lights are used during the test, one area of the brain (the occipital region) may have a brief response after each flash of light, but the brain waves are normal.

Abnormal EEG pattern

Video EEG

Video EEG records seizures on videotape and on computer so that the doctor can see what happens in preictal phase (just before), ictal phase (during), and post ictal phase (right after a seizure).

This test can be very helpful in finding the specific area of the brain that the seizures may be coming from.

Ambulatory EEG monitoring

In ambulatory EEG monitoring, the person is able to move around, and the test allows for long periods of time in recording of electrical activity in the brain.

MRI / CT brain

MRI has greatly enhanced the ability to detect certain lesions in the brain that cause seizures. (Lesion is defined as any diseased tissue.)

MRI is important in diagnosing the causes of epilepsy, and in evaluating potential candidates for surgery.