CALCA and keratoconus: The result of the one-way ANOVA shows a significant difference in KC density between groups (F2,57 = 8.07, p = 0.0008), and the post hoc t-tests index shows a lower KC density in AD patients compared with HCs (t = 3.7, p = 0.0007) and MCI patients (t = 3.42, p = 0.0015).