[1] Univ Edinburgh, Western Gen Hosp, Natl CJD Surveillance Unit, Edinburgh EH4 2XU, Midlothian, Scotland
[2] Univ Edinburgh, Western Gen Hosp, Dept Pathol, Edinburgh EH4 2XU, Midlothian, Scotland
[3] Vrije Univ Amsterdam, Med Ctr, Dept Neurol, Amsterdam, Netherlands
[4] Vrije Univ Amsterdam, Med Ctr, Dept Radiol, Amsterdam, Netherlands
[5] Vrije Univ Amsterdam, Med Ctr, Dept Pathol, Amsterdam, Netherlands