An endovascular prosthesis containing radiopaque markers for identifying the position of the prosthesis and for detecting any twisting of the prosthesis inside a corporeal vessel. The prosthesis may be a graft having a graft body with a wall defining a lumen. A plurality of radiopaque markers are disposed on the wall of the graft, with each individual marker appearing identical under fluoroscopy regardless of the grafts orientation inside the corporeal vessel, but the relative positions of individual markers relative to each other in a set indicate the prosthesis position and orientation.
