Tests and Diagnosis

Diagnosing epilepsy requires several types of tests and studies to ensure your symptoms and sensations are the results of epilepsy and not another neurological condition. The tests doctors most commonly use include:


  • Blood tests. Your doctor will take samples of your blood to test for possible infections or other conditions that might explain your symptoms. The test results might also identify potential causes for epilepsy.


  • EEG. An electroencephalogram (EEG) is a tool that most successfully diagnoses epilepsy. During an EEG, doctors place electrodes on your scalp. These electrodes sense and record the electrical activity taking place in your brain. Doctors can then examine your brain patterns and find unusual activity, which may signal epilepsy. This test can identify epilepsy even when you’re not having a seizure.


  • Neurological examination. As with any doctor’s office visit, your doctor will want to complete full health history. They will want to understand when your symptoms began and what you have experienced. This information can help your doctor determine what tests are needed and what types of treatments may help once a cause is found.


  • CT scan. A computed tomography (CT) scan takes cross-sectional pictures of your brain. This allows doctors to see into each layer of your brain and find possible causes of seizures, including cysts, tumours, and bleeding.


  • MRI. Magnetic resonance imaging (MRI) takes a detailed picture of your brain. Doctors can use the images created by an MRI to study very detailed areas of your brain and possibly find abnormalities that may be contributing to your seizures.


  • fMRI. A functional MRI (fMRI) lets your doctors see your brain in very close detail. An fMRI allows doctors to see how blood flows through your brain. This may help them understand what areas of the brain are involved during a seizure.


  • PET scan. A positron emission tomography (PET) scan uses small amounts of low-dose radioactive material to help doctors see your brain’s electrical activity. The material is injected into a vein and a machine can then take pictures of the material once it has made its way to your brain.