Abstracts

Rationale: Supplementary motor seizure is clinically associated with symptomatic involvement in the supplementary sensori-motor area (SSMA) and adjacent cortical areas, but patients with epileptogenic area itself arising exclusively from the SSMA (SSMA epilepsy) are rare. Only a minority remain seizure free after a long-term follow-up period. We reported clinical, noninvasive and invasive EEG findings and surgical outcome for 6 adult patients with intractable SSMA epilepsy. Methods: We evaluated 6 adult patients with intractable SSMA epilepsy. All patients had preoperative brain MRI, Wada test, neuropsychological test, noninvasive video-EEG monitoring, interictal and ictal brain SPECT. Invasive video-EEG monitoring using subdural grid and strip was performed in all patients. Results: In 6 patients, MRI findings were normal in 4 patients and focal abnormalities on the SSMA in 2 patients. We recorded typical SSMA semiology in all patients. Interictal and ictal SPECT were correctly lateralized in 1 patient. Noninvasive and invasive EEG recordings showed the interictal and ictal epileptiform discharges on the right SSMA in 4 and left SSMA in 2 patients. We resected right SSMA in 4 and left SSMA in 2. Surgical outcome (follow-up period: 49 ± 15.8 months) was Engel's classification Class I in 5 patients and Class II in 1 patients. Long-term neurological follow-up revealed no postoperative neurological deficits. Histopathologic findings revealed cortical dysplasia in 5 and unremarkable in 1 patient. Conclusions: Resection of SSMA on SSMA epilepsy has excellent surgical outcome in long-term follow-up, regardless of normal or abnormal MRI