"A neurologist can follow a patient for 30 years in consultation without ever having seen one of their seizures. In the epileptology unit, we record the seizure using EEG/video monitoring to try to trace the origin and trajectory of this seizure in the brain". Professor Michel BAULAC, Coordinator of the Epileptology Unit, Nervous System Diseases Unit, Pitié-Salpêtrière Hospital.  
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Diagnosis of epilepsy

The diagnosis of epilepsy is based on the clinical description of the seizures and the electroencephalogram (EEG), which measures the electrical activity of the brain using electrodes placed on the scalp. The EEG is used to determine whether the epilepsy is focal or generalised.

In some cases, continuous 24-hour recording of the EEG, coupled with video, is essential to establish a definitive diagnosis and guide treatment.

When a diagnosis of focal epilepsy is made, it is essential to carry out a magnetic resonance imaging (MRI) scan to look for any brain lesions causing the epileptic syndrome.


When the epilepsy is focal and persists despite appropriate medication, and no lesion is identified on the MRI, it may be necessary to explore the brain using intracerebral electrodes to record the EEG within the cortical generators.