ABSTRACT
BACKGROUND: To investigate the effects of topiramate (TPM) or lamotrigine (LTG) on cerebral glucose metabolism, we performed 18F-fluorodeoxy glucose positron emission tomography (FDG-PET) before and after medication in patients with drug naive idiopathic generalized epilepsy. METHODS: Thiry-three patients with newly diagnosed as idiopathic generalized epilepsy (IGE) or IGE without antiepileptic drugs after diagnosis were included. Pre- and post-antiepileptic drug FDG-PET were performed (before and after TPM or LTG administration) in 33 subjects treated with TPM or LTG who had been seizure free for at least 8 weeks. Sixteen of patients received TPM (M/F=8/8, aged 29.2+/-12.3 years) and 17 LTG (M/F=8/9, 26.8+/-9.3 years). For statistical paramateric (SPM) analysis, all PET images were spatially normalized to the standard PET template and then smoothed using a 12-mm full width at half-maximum Gaussian kernel. The paired t-test was used to compare pre- and post-medication FDG-PET images. RESULTS: SPM analysis of post- and pre-medication FDG-PETs showed TPM reduced glucose metabolism markedly in the thalamus, corpus callosum, and white matters, whereas LTG decreased glucose metabolism in cortico-striato-entorhinal areas with a false discovery rate corrected p<0.05. No brain region showed post-medication hypermetabolism in either group. CONCLUSION: Our study demonstrates that both TPM and LTG affect the cerebral glucose metabolism in drug naive idiopathic generalized epilepsy patients.