NEFL and myotonic dystrophy type 1: Moreover, NfL levels significantly correlated with Fazekas score, which is a semiquantitative index of WM damage, and this reflects the results of van der Plas et al., who found a significant correlation between WM FA values and plasma NfL levels, therefore suggesting that that either structural or functional WM alterations might be the main basis of cognitive and behavioral alterations in DM1 patients [34,35].