Implantation of a biosynthetic cornea in a patient with advanced keratoconus. (Because this video shows a surgery, portions of it are graphic.) An anterior lamellar keratoplasty procedure is performed to replace diseased human tissue with a laboratory-made alternative to human donor tissue. Total surgery time was 30 minutes. Sutures were removed from the cornea six weeks after surgery.

[Surgery and filming courtesy of Per surgery; video editing and caption courtesy of Neil Lagali; © Science/AAAS]