The vascular prosthesis includes a luminal graft component having at least one fenestration. At least one fenestration ring borders the at least one fenestration and is fixed to the luminal graft component. The fenestration ring includes a main component with two opposing ends and a connecting component. The diameter of the fenestration ring can expand upon insertion of a branch prosthesis through the fenestration ring during implantation at a surgical site. The vascular prosthesis can be implanted in a patient to thereby treat, for example, an arterial aneurysm, spanning a region of an aneurysm that includes at least one arterial branch.