Electroencephalogram (EEG)

If you have seizures that are hard to control with medication, your provider may admit you to the hospital for video EEG testing. This advanced type of EEG takes place in our inpatient epilepsy monitoring unit.  

During your stay, your brain waves will be recorded around the clock via EEG. You’ll also be monitored by a video camera. 

The purpose of this test is to capture—on video and EEG—the exact moment you have a seizure. The video footage lets us see what time your seizure occurred, how long it lasted, and what happens to you (better description of bodily movement and your cognitive abilities) during a seizure. And the EEG recording lets us see how that seizure affected your brain waves.  

Together, this information helps us confirm: 

• Whether your seizures are caused by epilepsy or another disorder 

• Where in the brain your seizures occur 

• Which treatment (either a new medication or surgery) is likely to work best 

Most people stay in our epilepsy monitoring unit for 3-5 days. That’s because we need you to stay long enough to have at least one seizure while you’re here.  

If your provider has recommended surgery to treat your epilepsy, you may need to have an intracranial EEG.  

Unlike standard EEG tests, which are noninvasive, intracranial EEG requires surgery. Instead of placing electrodes on your scalp, your provider will place them directly on your brain or deeper inside your brain. 

UI Health Care offers two types of intracranial EEG: 

• Stereo EEG (SEEG): Your surgeon drills tiny holes in your skull, then inserts small wires (depth electrodes) through the holes. These depth electrodes monitor and record your brain waves. 

• Electrode grid placement: Your surgeon temporarily removes a small piece of your skull (craniotomy). Then, they lay plastic strips or sheets containing many electrodes across your brain’s surface. 

For many patients, intracranial EEG is an important step before surgery. It pinpoints where in the brain your seizures start. And it creates a map of the “functional” areas in your brain (the spots that control speech, movement, and more). This helps your surgeon see where they need to operate and which areas to avoid.