Long-term seizure outcome in patients undergoing resection of lesions detected by magnetic resonance imaging.

The long-term efficacy of resective surgery was investigated in patients with lesions detected by magnetic resonance (MR) imaging. Thirty of 47 patients who had undergone lesionectomy between 1987-2001 were followed up by questionnaire. Patients with extratemporal resections outnumbered those with temporal lobe resections. The mean follow-up period was 12.4 +/- 3.7 years. Outcomes were graded according to Engel's criteria, and an arbitrary seizure outcome score was given for quantitative assessment. The mean seizure outcome scores were significantly lower in the early childhood (less than 3 years) onset group than in the late childhood (3 to 15 years) onset group, and significantly lower in the extratemporal resection of the cortical dysplasia group than in the temporal resection and the extratemporal resection of non-cortical dysplasia groups. This study indicated that lesionectomy based on MR imaging findings in patients with intractable epilepsy achieved effective long-term seizure control, and the outcome was related mainly to the pathology of the epileptogenic lesions and the temporal or extratemporal location.