question: Creutzfeldt-Jakob disease (CJD) is a rapidly progressive, fatal neurodegenerative disorder belonging to the family of transmissible spongiform encephalopathies. The disease is believed to be caused by an abnormal isoform of a cellular glycoprotein known as the prion protein. Our patient is an 84-year-old Caucasian man who presented to the geriatric clinic for evaluation of short-term memory loss and decreased concentration which started 3 months prior to initial evaluation. Rapid progression of dementia demonstrated by severe impairment in tasks with a predominantly visual component, including visual scanning, perceptual reasoning and visual spatial processing. Diagnosis of CJD was determined by characteristic ribboning on brain MRI as well as notable real-time quaking-induced conversion on cerebrospinal fluid.