Lateralization value of peri-ictal headache in drug-resistant focal epilepsy.

Objective: To examine the lateralizing value of unilateral peri-ictal and interictal headaches in patients with drug-resistant focal epilepsy (DRFE).

Methods: Four-hundred consecutive patients undergoing presurgical evaluation for DRFE were interviewed. Patients with headache were broadly divided into two groups: peri-ictal and interictal headache.