Abstract: The invention relates to a stent-graft prosthesis with a toroidally expandable sleeve (34) which has at least two opening attachments (36 and 37) and is made of flexible material for internal lining of an arterial aneurysm (1) and, where appropriate, with an aortic insert (23) associated with the sleeve (34), in the form of a vascular prosthesis with expandable supporting structures (39, 40) for fixing the aortic insert (23) in the sleeve (34) in the region of the opening attachments (36 and 37) thereof. The sleeve is designed as foldable toroid. The shape of the sleeve in the unfolded state is adapted to the shape of an aneurysm.