Patent ID: 8066754

Claim:
A medical device comprising: a catheter, the catheter having a distal portion, the distal portion having a tip region, and a proximal portion comprising: an inner shaft, the inner shaft having a distal portion and a proximal portion, wherein a portion of the distal portion of the inner shaft defines a stent receiving region; a distal outer sheath, the distal outer sheath being about the inner shaft and being longitudinally movable relative thereto between an extended position, which is at least partially about the stent receiving region, and a retracted position, a portion of the distal outer sheath defining a stent retaining region at the distal portion of the catheter, the stent retaining region being disposed about the inner shaft and being longitudinally moveable relative thereto, the stent retaining region being moveable between the extended position and the retracted position, which is proximal to the extended position, wherein, when the distal outer sheath is in the extended position, the stent retaining region is disposed about the stent receiving region and, when it is in the retracted position, the distal outer sheath is proximally removed from the stent receiving region; a proximal outer sheath, the proximal outer sheath being disposed about the inner shaft and being longitudinally fixed relative thereto, wherein the proximal outer sheath is positioned proximal to the stent receiving region and is sealingly engaged with the distal outer sheath; a rolling membrane having a first end and a second end, the first end being sealingly engaged with the distal outer sheath and the second end being sealingly engaged with the inner shaft at a point on the inner shaft proximal to the entirety of the stent receiving region, wherein the stent receiving region is between the rolling membrane and inner shaft when the distal outer sheath is in its extended position and wherein the stent retaining region of the distal outer sheath positioned radially around the rolling membrane when the distal outer sheath is in its extended position has a greater hoop strength than the rolling membrane and is less flexible than the rolling membrane, the rolling membrane having an inner layer and an outer layer, where the inner layer of the rolling membrane has a lower coefficient of friction than a coefficient of friction of the outer layer of the rolling membrane; and an intra-catheter space, the intra-catheter space being defined by, at least in part, the rolling membrane and the distal outer sheath, the catheter being constructed and arranged such that the pressurization of the intra-catheter space causes the distal outer sheath to move distally relative to the inner shaft.