Abstract: A luminal prosthesis comprises a plurality of axially arranged radially expandable stent segments 22,23 having coupling parts 20,21 for coupling of the segments 22,23. The segments 22,23 are movable between a collapsed delivery configuration in which the coupling parts 20,21 of the segments are interengaged and a deployed configuration in which the coupling parts 20,21 are disengaged. The stent segments 22,23 have means to delay the disengagement of the coupling parts 20,21 until the stent segments are close to the deployed configuration. A female coupling part 20 comprises an axially extending passageway having an entrance 30 to receive a corresponding axially extending male part 21 of an adjacent stent segment. The delay means may comprise first mating parts 40,41 and second mating parts 50,51 which are axially spaced-apart along the passageway. The second mating parts 50,51 may be located at an end of the passageway remote from the entrance to delay separation.

Abstract: A stent delivery balloon (1) is used to deploy a plurality of mini-stents (5) into a bodily lumen at a controlled spacing. The balloon (1) has formations (3) for retaining the stents in a designed position. The formations may comprise ridges (3), or retractable bridging elements, on the surface of the balloon (1) to control both the expansion of the multiple stents (5) from a single balloon (1) and also the coverage of the vessel wall following stenting.