Stent delivery system for a radioisotope stent

Claim 1

A system for maintaining the patency of a blood vessel of a human body, the system comprising: a flexible guide wire; a stent delivery catheter in the form of an elongated cylindrical tube having a distal section and having a longitudinally directed central lumen for slideable insertion therethrough of the flexible guide wire, the stent delivery catheter also including a deployable radioisotope stent mounted onto the distal section of the cylindrical tube and a proximal radioactive marker band mounted just proximal to the stent and a distal radioactive marker band mounted just distal to the stent; and a balloon angioplasty catheter having a distal section and having an inflatable balloon placed at the distal section of the balloon angioplasty catheter, the balloon angioplasty catheter being adapted to be placed co-axially over the guide wire and within the stent delivery catheter, the inflatable balloon being adapted to expand the radioisotope stent and both marker bands against the wall of a blood vessel when the inflatable balloon is inflated.

Claim 2

A system for maintaining the patency of a blood vessel of a human body, the system comprising: a flexible guide wire; a stent delivery catheter in the form of an elongated cylindrical tube having a distal section and having a longitudinally directed central lumen for slideable insertion therethrough of the flexible guide wire, the stent delivery catheter also including a deployable radioisotope stent mounted onto the distal section of the cylindrical tube and a proximal radioactive marker band mounted just proximal to the stent and a distal radioactive marker band mounted just distal to the stent; and a balloon angioplasty catheter having a distal section and having an inflatable balloon placed at the distal section of the balloon angioplasty catheter, the balloon angioplasty catheter being adapted to be placed co-axially over the guide wire and within the stent delivery catheter, the inflatable balloon being adapted to expand the radioisotope stent and both marker bands against the wall of a blood vessel when the inflatable balloon is inflated.

Claim 14

A method for dilating an arterial stenosis in the vascular system of a human body and also eliminating the edge effect experienced when a radioisotope stent is placed at the site of the dilated stenosis, the method comprising the following steps: (a) placing a guide wire through the vascular system of the human body until the distal end of the guide wire lies distal to the arterial stenosis; (b) advancing a stent delivery catheter over the guide wire until a radioisotope stent located at a distal section of the stent delivery catheter is longitudinally centered at the site of the arterial stenosis, the stent delivery catheter also including a proximal radioactive marker band located just proximal to the radioisotope stent and a distal radioactive marker band located just distal to the radioisotope stent; (c) advancing a balloon angioplasty catheter over the guide wire and within the stent delivery catheter until an inflatable balloon located at a distal section of the balloon angioplasty catheter is longitudinally centered within the radioisotope stent of the stent delivery catheter; (d) inflating the inflatable balloon until the radioisotope stent, the proximal radioactive marker band and the distal radioactive marker band are all expanded radially outward so as to be in close contact with the arterial wall at the site of the arterial stenosis; (e) maintaining the balloon in its inflated state until the regions of the arterial wall just proximal and just distal to the edges of the radioisotope stent experience a radiation dose of between 300 cGy and 3,000 cGy; (f) deflating the balloon; and (g) removing the stent delivery catheter, the balloon angioplasty catheter and the guide wire from the vascular system of the human body.

Claim 15

A method for dilating an arterial stenosis in the vascular system of a human body and also eliminating the edge effect experienced when a radioisotope stent is placed at the site of the dilated stenosis, the method comprising the following steps: (a) placing a guide wire through the vascular system of the human body until the distal end of the guide wire lies distal to the arterial stenosis; (b) advancing a stent delivery catheter over the guide wire until a radioisotope stent located at a distal section of the stent delivery catheter is longitudinally centered at the site of the arterial stenosis, the stent delivery catheter also including a proximal radioactive marker band located just proximal to the radioisotope stent and a distal radioactive marker band located just distal to the radioisotope stent; (c) advancing a balloon angioplasty catheter over the guide wire and within the stent delivery catheter until an inflatable balloon located at a distal section of the balloon angioplasty catheter is longitudinally centered within the radioisotope stent of the stent delivery catheter; (d) inflating the inflatable balloon until the radioisotope stent, the proximal radioactive marker band and the distal radioactive marker band are all expanded radially outward so as to be in close contact with the arterial wall at the site of the arterial stenosis; (e) maintaining the balloon in its inflated state until the regions of the arterial wall just proximal and just distal to the edges of the radioisotope stent experience a radiation dose of between 300 cGy and 3,000 cGy; (f) deflating the balloon; and (g) removing the stent delivery catheter, the balloon angioplasty catheter and the guide wire from the vascular system of the human body.