Seizure Classification and Goals of Therapy

Amit Verma, MD: The International League Against Epilepsy [ILAE] revised their classification system a few years ago. We no longer use terms like partial seizures or generalized seizures; we label seizures more in terms of networks. If the seizures start in a specific area or if the patient also has focal networks, they are called focal onset seizures. If they involve networks on both sides of the brain, they’re considered to be generalized onset. If we are not sure whether it’s a focal network or a generalized network, then we use the term unknown onset.

To subcategorize them, if a person loses awareness during the seizure, that would be a focal seizure with loss of awareness or a focal unaware seizure. If they don’t lose awareness, then it would be a focal onset seizure without loss of awareness. Similarly, if they have motor symptoms during the seizure where they have motor movements, then that would be a focal onset seizure with motor symptoms. It is the same with generalized seizures, where the generalized onset could be generalized with motor symptoms or without motor symptoms. There has been a shift in terms of how we refer to these seizures or classify these seizures based on the new ILAE classification system.

When we talk about treatment for patients, the goal is always seizure freedom. We would define seizure freedom as the patient having no seizures. One of the issues is that we can only go by what the patients report. If the patients tell us they’re seizure-free, then we would consider that to be seizure freedom.

Achieving seizure freedom is the goal with all our patients. Sometimes, we’re unable to achieve that goal because if somebody has tried or failed several medications, it may be difficult to achieve that goal. Even in those circumstances, if we can’t achieve seizure freedom, then our goal of treatment would be to minimize adverse effects. We would have a patient on as few medications as possible because all those factors are going to impact the patient’s quality of life, whether they’re still having seizures or whether they have significant adverse effects related to the medications that we’re giving them. We want the patients to be seizure-free; that’s always the goal. If we can’t achieve that, then we want to try to give them the best quality of life possible by minimizing adverse-effect profiles.