Functional cortical mapping with subdural electrode arrays in brain tumor resection

Thirty-four patients with brain tumors adjacent to critical functional cortex underwent functional mapping with subdural electrode arrays (SEA). The goal was to achieve maximal tumor resection without producing a neurologic deficit. Twenty-eight patients had seizures, and for them SEA was also used to identify epileptogenic cortex based on ictal and interictal recording. Epileptogenic cortex was resected with the tumor whenever possible. We describe the use of SEA technique in tumor surgery. We report the percentages of gross tumor resection achieved and the complication rate for the entire group of 34 and briefly present seizure outcome for those with seizures. SEA had unique advantages for functional mapping in tumor surgery and was safe and effective in that setting.