Wristwatch magnetization and demagnetization in MR installations.

70% of the patients affected by PSP are not correctly diagnosed in the first 2 to 3 years of the disease. I personally have followed three patients who at CT presented the features of PSP while none of them showed clinical signs definitively suggestive of the disease. This suggests that the CT findings could be present before the complete clinical manifestation of the syndrome, at least in a number of cases of PSP. It would be of interest to know if other authors have had the same experience. Additional clinical, radiologic, and pathologic correlations are necessary to confirm this hypothesis. Paolo Ambrosetto Neurological Institute, University of Bologna, Medical School via Ugo Foscolo 7-40123, Bologna, Italy