Effects of Tailored Anterior Temporal Lobectomy on Intelligence and Memory Function in Patients with Mesial Temporal Lobe Epilepsy

Kwon, O Dae; Kim, Ji Eun; Kim, Jin Suk; Yi, Sang Doe

Abstract

BACKGROUND: There exist considerable debates concerning about the effects of epilepsy surgery on cognitive function. To evaluate the effects of tailored anterior temporal lobectomy with amygdalohippocampectomy (ATLAH) on intelligence and memory, we compared the pre- and post-operative cognitive function in patients with mesial temporal lobe epilepsy (MTLE).
METHODS
Thirty six patients who received unilateral tailored ATLAH from 1993 to 1997 and had been seizure-free for at least two years postoperatively were selected. Mean age at the time of surgery was 26.8 years and mean period of postoperative follow-up was 47 months. The change of cognitive function was assessed pre-and post-operatively using Korean Wechsler Adult Intelligence Scale (K-WAIS) and Rey memory test. We also assessed the correlation between the extent of hippocampal and lateral temporal cortical resection and cognitive changes respectively.
RESULTS
In total patients (N=36), there was statistically significant improvement in performance IQ (PIQ, p<0.05), full scale IQ (FIQ, p<0.05), and auditory verbal learning test (AVLT). In the right temporal lobectomy group (N=16), improvement in PIQ, FIQ, and AVLT reached to statistical significance (p<0.05). In the left temporal lobecto-my group (N=20), improvement in PIQ was significant (p<0.05). In terms of the size of resection, there were tendencies that the cognitive function is more improved in patients with larger hippocampal resection (>2 cm) and in patients with smaller temporal cortical resection (4 cm).
CONCLUSIONS
Patients became seizure free after tailored ATLAH may have improvement in performance IQ and full scale IQ. Right side resection, larger hippocampal resection, and smaller lateral temporal resection show better postoperative cognitive function. (J Korean Neurol Assoc 19(2):116~124, 2001)