Michael S. Porter
Eric C. Nordby
Epilepsy is a chronic neurological disorder characterized by recurrent unprovoked seizures resulting from abnormal excessive or synchronous neuronal activity in the brain. This condition can affect consciousness, movement, sensation, or other neurological functions depending on the brain region involved. The specific manifestations of seizures vary widely among individuals with epilepsy.
A clinical diagnosis of epilepsy is made when any of the following conditions are met:
- A person experiences at least two unprovoked seizures occurring more than 24 hours apart.
- A person has one unprovoked seizure and the probability of further seizures is similar to the general recurrence risk (at least 60%) after two unprovoked seizures over the next 10 years.
- A specific epilepsy syndrome is identified that confers a diagnosis.
This practical clinical definition aligns with the International League Against Epilepsy (ILAE) and helps guide treatment decisions.
Epilepsy affects approximately 50 million people worldwide. The prevalence and impact vary by region, age, and underlying cause.
Epilepsy can result from a variety of causes, including:
- Genetic factors
- Structural abnormalities such as stroke, tumors, cortical dysplasia
- Metabolic conditions
- Infectious diseases affecting the brain (e.g., meningitis, encephalitis)
- Brain injuries, including those occurring during birth
In many cases, neuroimaging and other studies reveal no identifiable pathology.