Prognosis of Temporal Lobectomy for Temporal Lobe Epilepsy Patients with Mental Retardation

Background : For decades, patients with epilepsy and mental retardation (MR) have been considered as a relative contraindication for focal resective epilepsy surgery. However, considerable debate exists concerning whether the pres - ence of MR is a contraindication for epilepsy surgery or not. We examined the postsurgical seizure outcome of temporal lobe epilepsy (TLE) according to preoperative intelligence scores and the relationship between preoperative intelligence and postsurgical seizure outcomes of TLE. Methods : We investigated 131 patients with TLE divided into two groups according to standard IQ ranges and seizure outcomes were compared by Engel's classification. Results : The percent- age of seizure free patients after surgery was 66.4% in all patients and the percentage in patients with and without MR were 60.7% and 68%, respectively. The age at seizure onset was significantly different between the MR group and non the MR group. However, other factors which have been thought to affect the intelligence of patients with TLE were not significantly different between the two groups. The best postoperative seizure outcome was shown in the borderline group, where the frequency of hippocampal sclerosis and age at seizure onset were significantly higher compared to the other groups. Conclusions : Although preoperative MR has been regarded as a predictor for a poor prognosis of surgi - cal outcome, our results suggest that MR alone is not a contraindication for epilepsy surgery. Therefore, epilepsy patients with MR who meet other inclusion criteria for epilepsy surgery should not be rejected for epilepsy surgery. J Korean Neurol Assoc 18(5):595~600, 2000