Focal hypometabolism on [18F]FDG PET images in surgical candidates with epilepsy is particularly helpful in non-lesional cases. We describe here a case of subtle focal anterior temporal hypometabolism, detected visually on the basis of the left/right asymmetry, but still within normal ranges at an automated comparison with a reference database. The concordance with clinical and electroencephalographic assessments motivated a right anterior temporal lobectomy, and pathology showed changes consistent with a focal cortical dysplasia. This highlights the importance of carefully interpreting PET findings with a combined visual and automated evaluation.