Dupont S.,Epilepsy Unit and Rehabilitation Unit |
Dupont S.,Rehabilitation Unit |
Dupont S.,French Institute of Health and Medical Research |
Dupont S.,University Pierre and Marie Curie
Revue Neurologique | Year: 2015
After medial temporal lobe epilepsy (MTLE) surgery, there is considerable individual varia-tion in the extent, nature and direction of postoperative memory change. Before surgery, epileptic patients who are surgery candidates need precise information about the potential cognitive after effects, and particularly in temporal lobe epilepsy, postoperative memory changes. Clinical and neuropsychological data may bring useful information to predict the postoperative memory outcome, but, these data are not always sufficient to replace the Wada test, considered for a long time, as the gold standard to predict postoperative decline following surgery. In any case, numerous studies demonstrate that the Wada procedure can be nowadays reliably replaced by functional MRI (fMRI) activation studies. A vast majority of fMRI studies suggest that it is the functional adequacy of the resected hippocampus rather than the functional reserve of the contralateral hippocampus that determines the extent of postoperative memory decline. In addition, new functional neuroimaging procedures that explore more widespread network disruptions commonly found in MTLE such as diffusion-tensor imaging (DTI) or connectivity studies could in the future constitute a reliable approach combined with fMRI activation studies to significantly improve the prediction of postsurgical memory decline. © 2015 Elsevier Masson SAS. All rights reserved.