Focal epilepsy (also known as partial epilepsy) is a type of epilepsy characterized by recurrent seizures that originate in a specific area of the brain—referred to as the seizure focus. Unlike generalized seizures, which involve both hemispheres of the brain from the onset, focal seizures start in one hemisphere and may either remain localized or spread.

Key Features: Onset: Seizures begin in a defined cortical region.

Symptoms: Depend on the location of the seizure focus (e.g., motor, sensory, autonomic, or psychic symptoms).

Consciousness: May be preserved (focal aware seizures) or impaired (focal impaired awareness seizures).

Etiology: Can result from structural lesions (e.g., cortical dysplasia, tumors, strokes), infections, trauma, or may be idiopathic.

Diagnosis: Often involves EEG, MRI, and clinical evaluation.

Treatment: Includes antiepileptic drugs, and in drug-resistant cases, surgical resection or neurostimulation may be considered.