O133 Objective detection of cortical glucose metabolic abnormalities in children with epilepsy surgery: Validation with intracranial EEG. Issue 9 (September 2017) - Juhasz, Csaba
Abstract : Objective: To evaluate the accuracy of objectively identified hypo- and hypermetabolic cortex to detect the lobe(s) of seizure onset in young children with focal epilepsy. Methods: Presurgical 2-deoxy-2[18F]fluoro-D-glucose positron emission tomography (FDG-PET) scans of 37 children (mean age: 9.7 years) with drug-resistant focal epilepsy, who underwent 2-stage epilepsy surgery guided by subdural EEG, were compared to pseudo-normal pediatric control PET data ( N = 64; age 1–18 years, mean age: 9.3 years) by statistical parametric mapping (SPM). The control PET data were from non-surgical epileptic children with normal MRI and FDG-PET on expert visual assessment and were also used to create age-specific pediatric PET templates. Accuracy of intracranial seizure onset zone (SOZ) detection by SPM-defined FDG-PET abnormalities was determined on the lobar level. Results: At least one cluster of cortical metabolic abnormality was detected by SPM in 36 children. In the whole group, hypometabolic clusters had 75% sensitivity and 64% specificity to detect the SOZ lobe(s). Hypermetabolic clusters had a slighly higher specificity (69%) but low sensitivity (34%). A similar accuracy of SOZ detection was found in young children (<4 years of age). Discussion: Objective detection of metabolic abnormalities by PET is difficult in young children due to lack of age-matched healthy controls. The findings validate the use of SPM with an age-matched pediatric pseudo-normal control group. Conclusion: SPM with pediatric pseudo-normal control PET data can identify the lobe(s) of seizure onset with around 70% lobar accuracy even in young children. Significance: This approach extends the use of FDG-PET for the objective detection of metabolic abnormalities in the seizure onset lobe(s) to young children above 1 year of age.