There are more than 40 mutations, and most patients do not have a family history (although they may have a history of Alzheimer's or Parkinson's diseases). v CJD occurs in younger patients, mean age 28, longer duration (14 months) and is typically acquired in England or France rather than the US. The pulvinar sign is seen on T2 images Pulvinar brighter than PUT). EEG is abnormal only late in disease. Psych prodrome may occur and diagnosis can be made by tonsillar or brain biopsy. V CJD is transmissible by blood transfusions. Website pertaining to is found at: http://www.cjd.ed.ac.uk/criteria.htm/#vCJD .