Secondarily generalized seizure
A seizure that begins as a focal seizure but spreads to involve both brain hemispheres. Critical distinction in seizure classification documentation.
Full Definition
A secondarily generalized seizure starts as a focal seizure in one area of the brain but then spreads to involve both hemispheres, resulting in generalized tonic-clonic activity. This progression is also known as focal to bilateral tonic-clonic seizure in current terminology. The initial focal component may be so brief that it's not clinically apparent, making accurate diagnosis challenging. Understanding this progression is essential for proper treatment selection and surgical candidacy assessment.
Usage
Usage note: The newer term 'focal to bilateral tonic-clonic seizure' is preferred in recent literature.
In Context
- "The video EEG captured a secondarily generalized seizure originating from the right temporal lobe." — EMU report
- "Patients with secondarily generalized seizures may benefit from epilepsy surgery unlike those with primary generalized epilepsy." — Surgical evaluation