Epilepsy surgery in tuberous sclerosis: multistage procedures with bilateral or multilobar foci.

Refractory seizures are common in patients with tuberous sclerosis and can contribute to developmental delay and behavioral problems. Surgical intervention can reduce the seizure burden in selected patients with tuberous sclerosis and refractory epilepsy, thereby improving cognitive function, behavior, and quality of life. However, the risks of surgery are usually considered unacceptable when the epileptogenic focus lies over dominant hemisphere eloquent cortex or is multilobar. Multistage invasive monitoring can provide detailed data regarding the location and number of ictal foci and functional extraoperative mapping can precisely delineate the boundaries of eloquent areas of the brain. If independent ictal onsets are demonstrated, a staged surgical approach can allow a more aggressive yet safe procedure in selected patients. A combination of staged resection and multiple subpial transections may provide an opportunity to treat epileptogenic foci located over eloquent cortex. Bilateral staged resections can be used when independent bihemispheric foci are present in patients with tuberous sclerosis. This article presents two cases, one of which (case 2) was previously reported, on successful multistage surgical treatment of epileptogenic foci located over an eloquent cortex or in both hemispheres in children with tuberous sclerosis. This case is represented since there is additional follow-up available and the prior report was to a neurosurgical audience. This multistage approach permitted resection of epileptogenic foci that would traditionally have been considered inoperable.