Apparatus and method for deploying stent across adjacent tissue layers
Transluminal access system includes a stent delivery catheter having a handle control mechanism. The catheter comprises a number of components for establishing an initial penetration between adjacent body lumens and subsequently implanting a stent or other luminal anchor therebetween. Manipulation of the stent components is achieved using control mechanisms on the handle while the handle is attached to an endoscope which provides access to a first body lumen.
1. A method for delivering a stent from a first body lumen to a second body lumen through apposed walls of said lumens, said method comprising:
positioning an endoscope in the first body lumen adjacent to a target site on the wall of the first body lumen, which is a luminal wall;
advancing a catheter assembly in a working channel of the endoscope to locate a distal region of the catheter assembly at the target site;
advancing a portion of the catheter assembly through a hole in the apposed walls at the target site, the catheter assembly including a stent deployment sub-assembly;
expanding a distal flange on the stent in the second body lumen by retracting a sheath;
stopping the retraction of the sheath at a pre-determined distance that is less than a length of the stent;
drawing proximally on the stent deployment sub-assembly to pull the distal flange against the wall of the second body lumen to maintain the walls in apposition; and
after drawing proximally, expanding a proximal flange on the stent in the first body lumen to complete delivery by further retracting the sheath.
2. The method as in claim 1 , wherein the stent is self-expanding and the sheath is part of the stent deployment sub-assembly.
3. The method as in claim 1 , wherein the first body lumen is selected from the group consisting of an esophagus, a stomach, a duodenum, a small intestine, a large intestine, and the second body lumen is selected from the group consisting of a bile duct, a pancreatic duct, a gallbladder, a cyst, a pseudocyst, an abscess, a pancreas, a liver, an urinary bladder, a duodenum, a jejunum, and a colon.
4. The method as in claim 1 , wherein a needle is carried by the catheter assembly.
5. The method as in claim 1 , wherein during advancing the portion of the catheter assembly the stent deployment sub-assembly carries the stent over a needle.
6. The method as in claim 1 , further comprising penetrating the apposed walls at the target site to form the hole in the apposed walls.
7. The method as in claim 1 , further comprising:
deploying an anchor on a distal end of a tension wire in the second body lumen;
drawing proximally on the tension wire to maintain the walls in close apposition;
advancing the stent deployment sub-assembly while maintaining tension on the tension wire.
8. The method as in claim 7 , wherein deploying the anchor comprises advancing the tension wire through an axial passage of a needle after the needle has penetrated through the apposed walls.
9. The method as in claim 8 , wherein the anchor is a self-expanding structure formed integrally with the tension wire.
10. The method as in claim 9 , wherein the self expanding anchor structure deploys as the tension wire is advanced from the needle causing the anchor to be released from the axial passage of the needle and to cover a distal tip of the needle.
11. The method as in claim 1 , further comprising forming the hole in the apposed walls at the target site using a needle prior to advancing the portion of the catheter assembly through the hole in the apposed walls at the target site.
12. The method of claim 11 , wherein the needle is an electrosurgical needle.
13. The method as in claim 1 , wherein expanding the distal flange on the stent in the second body lumen forms a double-walled flange.
14. The method as in claim 1 , wherein expanding the distal flange on the stent in the second body lumen forms a lip on a distal side of the distal flange, wherein the lip on the distal side of the distal flange has an expanded diameter that is less than an expanded diameter of the distal flange on the stent.
15. The method as in claim 1 , wherein expanding the proximal flange on the stent in the first body lumen forms a double-walled flange.
16. The method as in claim 1 , wherein expanding the proximal flange on the stent in the first body lumen forms a lip on a proximal side of the proximal flange, wherein the lip on the proximal side of the proximal flange has an expanded diameter that is less than an expanded diameter of the proximal flange on the stent.
17. The method as in claim 1 , wherein the second body lumen comprises a gallbladder.
18. The method as in claim 1 , wherein the first body lumen is a stomach or duodenum.
19. The method as in claim 1 , wherein the first body lumen is a stomach and the second body lumen is a pseudocyst, jejunum, or duodenum.
20. The method as in claim 1 , wherein the second body lumen is a colon.
21. The method as in claim 1 , wherein retracting the sheath to the pre-determined distance includes retracting the sheath to a locking point on the catheter assembly.
22. The method as in claim 21 , further comprising unlocking the sheath prior to expanding the proximal flange.
23. The method as in claim 1 , wherein the pre-determined distance is calibrated to allow only the distal flange of the stent to be released.
24. The method as in claim 1 , wherein expanding the proximal flange on the stent in the first body lumen forms a fluid communication pathway through the stent between the first body lumen and the second body lumen.