Neuropsychological Effect of Temporal Lobe Resection in Preadolescent Children with Epilepsy

Abstract

Summary:Purpose: Numerous studies have demonstrated changes in cognitive, memory, and language functioning in adults and adolescents after temporal lobectomy, yet little information is available regarding neuropsychological outcome in preadolescent children.Methods: We studied pre-and postoperative neuropsychological test results from 14 children who underwent temporal lobe resection for intractable epilepsy at age 7-12 years (mean 9.4 years).Results: Thirteen patients (93%) had no seizures or less than one seizure a year at follow-up 23-48 months (mean 34 months) after operation. Postoperative neuropsychological testing was performed 6-9 months (mean 7 months) after surgery in 13 patients and 36 months after the first operation in 1 patient who underwent two-stage resection of a tumor. Verbal, Performance, and Full Scale IQ were initially in the lowaverage range, with no significant change across the pre-and postoperative evaluations. Immediate verbal memory performance decreased significantly in children who initially performed above the median preoperatively and tended to decrease in children who had left rather than right temporal lobe resection. Significant postoperative decreases in delayed memory scores were independent of preoperative ability or side of resection.Conclusions: Our small study suggests vulnerability to postoperative decline in immediate verbal memory scores in preadolescent children who have higher baseline immediate memory function or undergo left rather than right temporal lobe resection, similar to that observed in adolescents in adults. The entire group exhibited a statistically significant decrease in delayed verbal memory. Study of larger series of patients will be important to clarify further the short-and long-term risks and benefits of temporal lobe resection in childhood.

Memory impairment in children with temporal lobe epilepsy: a review

“…In children, the profile of memory impairment after surgery appears to be similar to that in adults (12,21,26) . Adams et al (1990) reported a decline of verbal memory after left temporal lobectomy, but no change after right lobectomy.…”

“…Szabo et al (1998) found a significant decline in immediate verbal memory after temporal lobectomy (seven right and seven left), especially in children (7 to 12 years) who had a high presurgical evaluation performance or underwent left rather than right ressections. Significant decline in the postsurgical scores of delayed memory was independent of presurgical performance and the side of the resection (26) . Duglos et al (1999) reported languagerelated cognitive decline after left temporal lobectomy (27) .…”

“…Different results on the outcome of memory after temporal lobe surgery in children have been reported, some findings showing memory decline (12,21,23,(26)(27) and other data showing no significant change (11,(29)(30)(31)(32)(33) . The discrepancy may be due to the fact that TLE in childhood is a different condition from TLE in adults, both in terms of clinical features and neuropathology (34) .…”

A disfunção do lobo frontal em crianças e adolescentes com epilepsia de lobo temporal e sua possível correlação com a ocorrência de transtornos psiquiátricos

“…No estudo de Szabó et al (19) , com 14 pré-adolescentes com ELT (idade média de 9,4 anos), foram realizadas avaliações neuropsicológicas pré e pós-operatórias e constatou-se a estabilidade do QI e a diminuição da memória verbal após ressecção do lobo temporal na infância. A relativa estabilidade das medidas de QI em pré-adolescentes indica que a habilidade intelectual geral não é intensamente afetada pela ressecção do lobo temporal.…”

“…Segundo Szabó et al (19) , poucos estudos avaliaram os efeitos da ELT e da lobectomia temporal na cognição de crianças com epilepsia. Na revisão realizada por estes autores, a maior parte das séries abordando este tópico tem resultados semelhantes aos dos estudos com adultos em conseqüência da população estudada, predominantemente composta por adolescentes, limitando as conclusões sobre as disfunções mnésticas em crianças pós-cirurgia do lobo temporal.…”