Focal lesion

This 5-year-old presented with status epilepticus to an outside hospital. Serial MRI scans were read by several experienced pediatric neuroradiologists as normal despite focal EEG abnormalities over the left central-temporal region. After failure of intravenous pentobarbital with coma and EEG burst suppression, the child was transferred for further management. Metabolic workup, including conjunctiva biopsy, was negative. FDG-PET and MRI co-registration identified an abnormal area of hypometabolism over a deep gyrus at the posterior end of the left Sylvian fissure (white arrow, both panels) consistent with the scalp EEG focus. In the operating room, this area was mapped and resected, and the pathology was identified as cortical dysplasia. The status epilepticus stopped; there was no language deficit; and she has remained seizure-free for over 5 years. This case is an example of a child who was initially classified as having unknown epilepsy (non-operative) but, instead, had a difficult-to-identify structural lesion that was causing status epilepticus. (Contributed by Dr. Gary W Mathern.)