FDG-PET in the diagnosis of complex partial status epilepticus originating from the frontal lobe

Complex partial status epilepticus of frontal origin can manifest as nonconvulsive behavioral symptoms that mimic psychiatric illness and, thus, may elude timely diagnosis. The diagnosis can be further delayed by absence of ictal activity on scalp electroencephalography when the ictal origin is orbitofrontal or mesial frontal. We describe the case of a 51-year-old woman with clinically subtle complex partial status epilepticus of left orbitofrontal origin, lacking any clear ictal pattern on the electroencephalogram, who was finally diagnosed using positron emission tomography with [18F]fluorodeoxyglucose (FDG-PET). Subsequent FDG-PET following 5 days of oxcarbazepine therapy demonstrated resolution of the left orbitofrontal hypermetabolic focus. FDG-PET is a potentially useful modality for diagnosing nonconvulsive status epilepticus that is not evident on electroencephalography.