ORBITOFRONTAL RESECTIONS FOR INTRACTABLE PARTIAL SEIZURES

The orbitofrontal cortex has extensive connections with limbic structu res that are often involved in intractable partial seizures. Although some cases of orbitofrontal epilepsy have been reported, the exact inc idence and optimal means of diagnosis and treatment of this condition are not well established. For 1 year, we included recordings from the orbitofrontal cortex in all cases of limbic epilepsy that required inv asive monitoring as part of a preoperative workup. We identified 3 cas es in which orbitofrontal resections were performed to control intract able partial seizures. In 1 case, an orbitofrontal resection based on physiologic data disclosed an area of focal cortical dysplasia that ha d not been identified by preoperative structural and functional imagin g. In the second case, the adjacent orbitofrontal area was resected co ncurrently with a dominant anterior temporal lobectomy (ATL). In the t hird case, a patient was seizure-free for 6 years after an ATL. The se izures recurred, however, and an orbitofrontal resection was performed on the same side as the original surgery. These patients had no uniqu e EEG or semiology profile that identified orbitofrontal seizures befo re invasive recordings were made. The orbitofrontal cortex may be the source of intractable partial seizures, and this should be considered in electrode implantation strategies for the preoperative evaluation o f patients with this disorder.