Abstracts

Rationale: Objective: The utilization of corpus callosotomy (CC) has evolved from one of conventional palliative treatment to one of adjunctive therapy before further surgical resection and more importantly as a lateralizing tool in a select group of patients where presurgical evaluation has been non- localizing. CC has been well accepted as a surgical option for atonic seizures commonly associated with Lennox Gastaut Syndrome. The object of this study is to review the varying roles of CC and its impact on seizure outcome in pediatric patients with intractable epilepsy. Methods: Methods: The authors retrospectively reviewed the Pediatric Epilepsy Surgery database of 63 patients who underwent CC from 1990-2010. Chart review established demographic data, race, age of surgery, EEG findings, MRI findings, concomitant syndrome or presence of infantile spasm, and pathology when available. Inclusion criteria for patients eligible for CC were multifocal EEG pattern or bisynchronous spike and slow wave activity with poorly lateralized scalp EEG. Outcome measures were determined by parental reporting. Post resection seizure outcomes were determined by Engel criteria. Results: Results: Of the 63 patients who underwent CC, 37 patients had conventional palliative surgery for atonic seizures associated with Lennox Gastaut Syndrome. A reduction of greater or equal to 75 percent in atonic seizures occurred in 75 percent of patients in this cohort. Twenty patients had nonconventional CC : 7 with adjunctive CC at the time of a cortical resection and 13 with CC for nonlocalized intractable complex partial and/or generalized tonic clonic seizures. Not surprisingly, given the baseline refractory nature of this population, the outcome of this combined cohort remained poor at 12 months (Engel class III or IV). Six patients underwent CC with the expectation of forced lateralization for focal resection. Of these 6 patients, subsequent grid placement with focal resection yielded 67 percent class I Engel outcome at 12 month follow up. Despite the lateralized findings on EEG, MRI findings in this cohort were nonlateralizing , including 4 normal MRIs, 1 lissencephaly, and 1 Dandy Walker syndrome. Conclusions: Conclusion: Medical management often fails in this intractable group of pediatric epilepsy patients. Presurgical evaluation may prove challenging in attempting to localize an epileptic focus. This review illustrates a broad use of CC in surgical planning. We discuss CC as an additive benefit in presurgical evaluation for hemispheric lateralization for management of intractable epilepsy in children. Although most patients continue to have seizures following CC, improvement in progression of an intractable disease as well as the possibility of subsequent resection of an epileptic focus proves worthwhile. In the absence of other lateralizing findings, CC should be considered as an additional therapeutic tool.