Intrastromal corneal ring segment implantation for high astigmatism after penetrating keratoplasty - Arriola-Villalobos, Pedro; Diaz-Valle, David; Luis Gueell, Jose; Teresa Iradier-Urrutia, Maria; Jimenez-Alfaro, Inigo; Cuina-Sardina, Ricardo; Manuel Benitez-del-Castillo, Jose (Journal Of Cataract And Refractive Surgery, 2009)