What is a characteristic EEG finding in Creutzfeldt-Jakob disease?

In Creutzfeldt-Jakob disease (CJD), a characteristic finding on the electroencephalogram (EEG) is the presence of periodic synchronous bi- or tri-phasic sharp waves. These EEG patterns are typically seen in patients with prion diseases, particularly in the variant forms. The sharp waves may appear at intervals and can be associated with the clinical features of CJD, which include rapidly progressive dementia, myoclonus, and other neurological deficits.

This specific pattern is significant because it helps in differentiating CJD from other forms of dementia or encephalopathy that may present with similar symptoms but do not have the same EEG characteristics. The detection of these periodic sharp waves can also assist in making a diagnosis of CJD, especially when combined with other clinical signs and supportive tests, such as MRI findings showing Caudate nuclei or cortical involvement.