To achieve transcatheter entry obliteration for Stanford type B dissection, the authors devised and developed a self-expandable intra-aortic prosthesis (IA graft). This graft consisted of a microporous polyurethane graft (wall thickness: 0.2 mm; average pore size: 0.1 mm) and an expandable metallic stent (Gianturco double stent) attached to the lumen surface of the polyurethane graft. Experimental dissections in the descending aorta of mongrel dogs were prepared. An IA graft was inserted through a femoral artery by a catheter sheath into which a compressed IA graft was installed and expanded at the entry site. After 30 min of graft implantation, closure of all the entry sites in four dogs was confirmed by aortography. The results suggest that the newly devised IA graft is extremely useful as a non invasive treatment for Stanford type B dissection.