Alien hand syndrome after epilepsia partialis continua: FDG PET and MRI studies

Abstract

Epilepsia partialis continua (EPC) is clinically defined as a syndrome of continuous focal jerking of a body part, usually a distal limb, occurring over hours, days, or even years. It is considered the status epilepticus equivalent of simple partial motor seizures. A 48-year-old right-handed man with a history of traumatic intracranial hemorrhage was admitted for right-sided hemiplegia and drowsiness after complex partial status epilepticus. An EEG showed periodic lateralized epileptiform discharges over the left hemisphere. Brain MRI revealed extensive multifocal encephalomalaciac changes in the left temporo-parieto-occpital lobe and both frontal lobes with some hemorrhagic residual change. After administration of a loading dose of intravenous phenytoin, his mental status returned to normal. However, his weakness only partially improved. [18F]Fluorodeoxyglucose PET (FDG-PET) demonstrated severe hypometabolism in the left cerebral hemisphere, including the basal ganglia and thalamus, with cerebellar diaschisis. At the 3-month follow-up, he complained of symptoms of alien hand phenomenon. Follow-up MRI revealed more extensive encephalomalaciac changes in previously noted regions with thinning of the posterior end of the body of the corpus callosum. Moreover, FDG-PET demonstrated persistent severe hypometabolism over the left cerebral hemisphere. We suggest that the alien hand phenomenon was a result of thinning of the corpus callosum related to EPC.