Focal electroencephalography abnormality in the early stage of sporadic Creutzfeldt–Jakob disease corresponding to neuroradiological findings: A magnetoencephalography experience

This study discusses the first electroencephalography (EEG) findings in two patients with sporadic Creutzfeldt–Jakob disease (sCJD) using magnetoencephalography (MEG). Case 1 involved a 71-year-old male who presented with progressive clumsiness of the right hand. An EEG performed 3 weeks after symptom onset revealed small periodic spikes over the left centroparietal region. MEG identified the spike source in the left parietal lobe, which subsequently exhibited glucose hypometabolism on positron emission tomography. Case 2 involved a 48-year-old male with progressive clumsiness and numbness in the left limbs. His EEG reported 3 weeks after onset, displayed rhythmic regional delta activity maximal in the right centroparietal region. MEG identified the delta source in the right parietal lobe, corresponding to hypoperfusion observed in single-photon emission computed tomography. In both cases, MEG successfully visualized electrophysiological dysfunction in the early stages of sCJD.