Outcome following multiple subpial transection in Landau-Kleffner syndrome and related regression

ObjectiveTo determine whether multiple subpial transection in the posterior temporal lobe has an impact on long-term outcome in children who have drug-resistant Landau-Kleffner syndrome (LKS) or other electrical status epilepticus during sleep (ESES)-related regression. Given the wide variability in outcomes reported in the literature, a secondary aim was to explore predictors of outcome. MethodsThe current study includes a surgery group (n=14) comprising patients who underwent multiple subpial transection of the posterior temporal lobe and a nonsurgery comparison group (n=21) comprising patients who underwent presurgical investigations for the procedure, but who did not undergo surgery. Outcomes were assessed utilizing clinical note review as well as direct assessment and questionnaires. ResultsThe distribution of nonclassical cases was comparable between groups. There were some differences between the surgery and nonsurgery groups at presurgical investigation including laterality of discharges, level of language impairment, and age; therefore, follow-up analyses focused on change over time and predictors of outcome. There were no statistically significant differences between the groups in language, nonverbal ability, adaptive behavior, or quality of life at follow-up. There was no difference in the proportion of patients showing improvement or deterioration in language category over time for either group. Continuing seizures and an earlier age of onset were most predictive of poorer quality of life at long-term follow-up (F-2,F-23=26.2, p=<0.001, R-2=0.714). SignificanceBoth surgery and nonsurgery groups had similar proportions of classic LKS and ESES-related regression. Because no significant differences were found in the changes observed from baseline to follow-up between the two groups, it is argued that there is insufficient evidence to suggest that multiple subpial transection provides additional benefits over and above the mixed recovery often seen in LKS and related regressive epilepsies.