The EEG and clinical evolution in Creutzfeldt-Jacob disease.

A total of nine EEGs were recorded serially from a typical, pathologically verified case of Creutzfeldt-Jacob disease (CJD). Typical periodic sharp waves (PSW) showed a progressive increase in duration, but the interval of PSW stayed fairly constant during the course of illness. Early in the illness there were PSW in approximately one-quarter of the records and this reached one hundred percent when clinical CJD was fully developed. Diagnosis of CJD on the basis of the EEG alone is difficult in the early phase of the disease due to the short duration of the PSW.