Ictal Smile Lateralizes to the Right Hemisphere in Childhood Epilepsy

PURPOSE: To analyze the localizing and lateralizing value of ictal smile (IS) in childhood epilepsy. METHODS: Incidence of IS in 309 videotaped seizures of 114 consecutive patients younger than 12 years with refractory frontal, temporal, or posterior cortex epilepsy were assessed. RESULTS: Among patients with right-sided epileptogenic zone, 12 (21%) of 57 had IS, whereas in patients with left-sided epilepsy, IS occurred only in one patient (1.8%; p < 0.01, chi(2) test). The incidence of IS was 11%, 3%, and 26% in the frontal, temporal, and posterior cortex subgroups, respectively. Logistic regression revealed that the localization of the epileptogenic region in the posterior cortex (p < 0.01), focal cortical dysplasia etiology (p = 0.012), and right-sided lateralization (p = 0.025) were independently associated with the presence of IS. CONCLUSIONS: Childhood IS lateralizes to the right hemisphere and localizes more frequently in the posterior cortex epilepsy.