ALDH7A1 and Schnyder corneal dystrophy: Non-selective inhibition of PDE by Pentoxifylline in the present study significantly increased the deformability of RBCs from SCD patients, both before and after the application of a constant shear stress for prolonged time, which confirms previous findings (Ugurel et al., 2019) but contrast with another study (Cummings and Ballas, 1990).