Telescopic wire guide

1. A telescopic wire guide configured for insertion through a working channel of an endoscope into a biliary or pancreatic duct, the telescopic wire guide comprising:

an outer wire having a proximal end and a distal end, the outer wire having a lumen formed from the proximal end through the distal end, the outer wire having a constant outer diameter along its entire length; and

a core wire disposed within the lumen and slidably movable therealong relative to the outer wire for distally telescopically extending the wire guide a predetermined length, the core wire comprising a proximal portion and a distal portion, the proximal portion comprising a stop to limit distal movement of the core wire, the distal portion defining a distal end that is retractable into the lumen of the outer wire proximally beyond the distal end of the outer wire, wherein the stop abuts the proximal end of the outer wire to define the predetermined length and defining an extended position in which the core wire extends the predetermined length from the outer wire, the core wire having a first length and the outer wire having a second length, the first length being greater than the second length, the core wire configured to slidably retract from the extended position to a retracted position in which the distal portion is disposed entirely within the lumen and the distal end of the core wire is disposed proximally from the distal end of the outer wire;

wherein the outer wire is a helical coil defining the lumen formed from the proximal end through the distal end thereof.

2. The wire guide of claim 1 wherein the outer wire comprises at least one of super elastic material, stainless steel wire, nitinol, cobalt-chromium-nickel-molybdenum-iron alloy, and cobalt-chrome alloy.

3. The wire guide of claim 2 wherein the outer wire comprises an outer coat.

4. The wire guide of claim 3 wherein the outer coat comprises polytetrafluoroethylene.

5. The wire guide of claim 1 wherein the core wire comprises super elastic material, stainless steel wire, nitinol, cobalt-chromium-nickel-molybdenum-iron alloy, or cobalt-chrome alloy.

6. The wire guide of claim 1 wherein the stop has a spherical shape, and the spherical shape defines a proximal end of the core wire.

7. The wire guide of claim 1 wherein the stop defines a proximal end of the core wire, the stop directly abutting the proximal end of the outer wire to define the predetermined length.

8. A telescopic wire guide configured for insertion through a working channel of an endoscope into a biliary or pancreatic duct, the telescopic wire guide comprising:

an outer wire having a proximal end and a distal end, the outer wire having a lumen formed from the proximal end through the distal end; and

a core wire disposed within the lumen and slidably movable therealong relative to the outer wire for distally telescopically extending the wire guide a predetermined length, the core wire comprising a proximal portion and a distal portion, the proximal portion comprising a stop to limit distal movement of the core wire, the distal portion defining a distal end that is retractable into the lumen of the outer wire proximally beyond the distal end of the outer wire, wherein the stop abuts the proximal end of the outer wire to define the predetermined length and defining an extended position in which the core wire extends the predetermined length from the outer wire, the core wire having a first length and the outer wire having a second length, the first length being greater than the second length, the core wire configured to slidably retract from the extended position to a retracted position in which the distal portion is disposed entirely within the lumen and the distal end of the core wire is disposed proximally from the distal end of the outer wire;

wherein the core wire can be fully withdrawn from the outer wire;

wherein the telescopic wire guide is configured to allow a medical component to pass over an entire length of the telescopic wire guide while the telescopic wire guide is disposed in a channel port of an endoscope;

wherein the outer wire is a helical coil defining the lumen formed from the proximal end through the distal end thereof.

9. The wire guide of claim 8 wherein the stop has a spherical shape, and the spherical shape defines a proximal end of the core wire.

10. The wire guide of claim 8 wherein the stop defines a proximal end of the core wire, the stop directly abutting the proximal end of the outer wire to define the predetermined length.

11. A telescopic wire guide configured for insertion through a working channel of an endoscope into a biliary or pancreatic duct, the telescopic wire guide comprising:

an outer wire having a proximal end and a distal end, the outer wire having a lumen formed from the proximal end through the distal end, the outer wire having a constant outer diameter along its entire length; and

a core wire disposed within the lumen and slidably movable therealong relative to the outer wire for distally telescopically extending the wire guide a predetermined length, wherein the core wire comprises a proximal portion and a distal portion, the proximal portion comprising a stop to limit distal movement of the core wire, the distal portion defining a distal end that is retractable into the lumen of the outer wire proximally beyond the distal end of the outer wire, wherein the stop abuts the proximal end of the outer wire to define the predetermined length and defining an extended position in which the core wire extends the predetermined length from the outer wire, the core wire configured to slidably retract from the extended position to a retracted position in which the distal portion is disposed entirely within the lumen and the distal end of the core wire is disposed proximally from the distal end of the outer wire;

wherein the outer wire is a helical coil defining the lumen formed from the proximal end through the distal end thereof.

12. The telescopic wire guide of claim 11 wherein the core wire has a first length and the outer wire has a second length, the first length being greater than the second length, wherein the first length is between 400 and 600 centimeters and the second length is between 200 and 300 centimeters.

13. The telescopic wire guide of claim 11 wherein the outer wire comprises super elastic material, stainless steel wire, nitinol, cobalt-chromium-nickel-molybdenum-iron alloy, or cobalt-chrome alloy.

14. The telescopic wire guide of claim 13 wherein the outer wire comprises an outer coat.

15. The telescopic wire guide of claim 14 wherein the outer coat comprises polytetrafluoroethylene.

16. The telescopic wire guide of claim 11 wherein the core wire comprises super elastic material, stainless steel wire, nitinol, cobalt-chromium-nickel-molybdenum-iron alloy, or cobalt-chrome alloy.

17. The telescopic wire guide of claim 11 wherein the stop defines a proximal end of the core wire, the stop directly abutting the proximal end of the outer wire to define the predetermined length.