Language-related cognitive declines after left temporal lobectomy in children

Presented is a case series demonstrating that clinically significant langua ge-related cognitive declines not detected by intelligence quotient (IQ) te sting occur after left temporal lobectomy in school-aged children. In this series, comprehensive preoperative and postoperative neuropsychologic evalu ations were completed in eight school-aged patients who underwent temporal lobectomy (five left, three right) for temporal lobe epilepsy. Mean age at surgery was 13 years, 11 months +/- 2 years, 1 month. Testing included meas urement of IQ, verbal learning, naming, visual memory, sight word recogniti on, reading comprehension, and calculation. All five left temporal lobectom y patients demonstrated significant language-related cognitive declines on postoperative neuropsychologic testing, including deficits in verbal IQ ton e patient), verbal learning (four patients), naming tone patient), and read ing comprehension tone patient). These deficits were clinically evident in four of the five left temporal lobectomy patients, leading to declines in e ducational performance. IQ testing alone did not reliably identify these de ficits. No significant declines were found after surgery in three right tem poral lobectomy patients. Average or high preoperative functioning may have predisposed patients to postoperative deficits in this series, whereas mag netic resonance imaging or pathologic abnormalities did not protect against postoperative deficits. Outcome studies of temporal lobectomy in childhood should use comprehensive neuropsychologic testing to identify cognitive de ficits. (C) 1999 by Elsevier Science Inc. All rights reserved.