Epilepsia partialis continua studied by PET

We report an [18F]fluordeoxyglucose (FDG)-PET study performed in an 11-year-old girl with a 5-month history of epilepsia partialis continua (epc). Visual inspection of PET images showed a hypermetabolic focus in the right central cortex and in the ipsilateral thalamus, which was confirmed by the absolute values of regional cerebral glucose metabolism (rCMRGlu). The thalamic hypermetabolism provides evidence for an involvement of thalamic nuclei in this ictally epileptic process. The scalp EEG revealed a theta-delta and sharp wave focus in the right Rolandic cortex at the same location as the hypermetabolic zone seen in PET. Simultaneously recorded EMG of the left tibialis anterior muscle showed regular jerks, time-locked to the sharp waves at the right central region, and myoclonic 'storms' during focal motor seizures. The results of the brain biopsy and the child's clinical course led us to a diagnosis of 'chronic encephalitis' of Rasmussen.