Stone retrieval balloon catheter
A device for removing a urinary tract stone from a ureter may include an outer shaft, an inner shaft extending coaxially within the outer shaft, a self-expanding wire basket attached to a basket shaft extending coaxially within the inner shaft, an inflatable balloon and a handle. The balloon main include a rounded distal tip. The handle may include an inversion slider coupled to the inner shaft and configured to actuate the inner shaft, thereby inverting the distal tip of the inflatable balloon to form a pocket adapted to receive a urinary tract stone. The handle may also include a basket slider coupled to the basket shaft and configured to actuate the basket shaft to move the wire basket in and out of the inner shaft.
1. A method for removing a urinary tract stone, the method comprising:
advancing a distal end of a ureteroscope into a body lumen to a location near the urinary tract stone;
advancing a distal end of a flexible stone removal device out of the distal end of the ureteroscope;
sliding a basket slider distally along a handle of the stone removal device to advance a wire basket out of an inner shaft of the stone removal device, thus allowing the wire basket to expand;
sliding the basket slider proximally along the handle to trap the urinary tract stone within the wire basket;
inflating an inflatable balloon on the stone removal device;
sliding an inversion slider proximally along the handle to invert a rounded distal tip of the inflatable balloon, wherein the inversion slider is frictionally coupled with the basket slider, and wherein sliding the inversion slider proximally automatically slides the basket slider proximally to pull the wire basket and the trapped urinary tract stone into the rounded distal tip of the inflatable balloon; and removing the ureteroscope and the stone removal device from the body lumen, along with the urinary tract stone, while the urinary tract stone is at least partially located inside the inflatable balloon.
2. The method of claim 1 , wherein inflating the inflatable balloon comprises inflating to a first, lower pressure, and wherein the method further comprises inflating the inflatable balloon to a second, higher pressure for dilating a narrowed portion of the body lumen, before trapping the urinary tract stone.
3. The method of claim 1 , further comprising unlocking the inversion slider before sliding it proximally along the handle.
4. The method of claim 1 , further comprising visualizing at least one of the steps of the method, using the ureteroscope.
5. The method of claim 1 , wherein advancing the distal end of the stone removal device comprises advancing the distal end of the device distally beyond the urinary tract stone, the method further comprising pulling the stone removal device proximally to surround the urinary tract stone with the wire basket.
6. The method of claim 1 , wherein the urinary tract stone comprises a urinary tract stone fragment.
7. The method of claim 1 , wherein the urinary tract stone comprises a urinary tract stone fragment, and wherein at least part of the method is performed during a lithotripsy procedure, to help prevent movement of the urinary tract stone fragment into a kidney.
8. The method of claim 1 , further comprising depressing the inversion slider before sliding it, to unlock the inversion slider from an inversion slider lock in the handle.
9. The method of claim 1 , further comprising holding a finger on the basket slider during movement of the inversion slider to override the automatic movement of the basket slider.
10. The method of claim 1 , wherein sliding the basket slider does not automatically move the eversion slider when the eversion slider is locked in an inversion slider lock in the handle.
11. The method of claim 1 , wherein the inflatable balloon is inflated sufficiently to dilate a narrow portion of the body lumen.
12. The method of claim 1 , further comprising inflating the balloon at least one time during removal of the stone removal device from the body lumen, to dilate a narrow portion of the body lumen.
13. The method of claim 1 , further comprising removing air from the inflatable balloon to reduce pressure in the inflatable balloon before inverting the rounded distal tip of the inflatable balloon.
14. The method of claim 1 , wherein the urinary tract stone is less than 5 mm in diameter.