Seitz BML, et al. - The effect of sequential double running suture removal over the corneal curvature following penetrating keratoplasty (PK) was evaluated in this study, comparing mechanical and nonmechanical excimer laser trephination. A better alignment of the graft in the recipient bed after excimer laser trephination was indicated by less change in astigmatism and the base curve after sequential removal of a double running suture. Astigmatism decreased or remained unchanged in 79% of patients after excimer laser keratoplasty and increased in 80% of patients after conventional motor trephination, following double running suture removal.