MAPT and Schnyder corneal dystrophy: When presented as the first exam, the etiological diagnosis changed in 17% (4/24; χ2 = 0, p = 1.00) of SCD patients after amyloid-PET, and in 17% (4/24; χ2 = 0.25, p = 0.617) of SCD patients after tau-PET (Table 2), with no difference between the two exams (χ2 = 0, p = 1.00).