Stone retrieval balloon catheter

Abstract

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.

What is claimed is: 
     
         1 . A device for removing a urinary tract stone, the device comprising:
 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, wherein the wire basket is configured to expand from a collapsed configuration inside the inner shaft to an expanded configuration when advanced out of a distal end of the inner shaft;   an inflatable balloon, comprising:
 a distal attachment leg at a distal end of the inflatable balloon, attached to the inner shaft; 
 a proximal attachment leg at a proximal end of the inflatable balloon, attached to the outer shaft; 
 a middle tubular portion between the distal end and the proximal end, the middle tubular portion having an expanded diameter of at least 5 millimeters; 
 a distal tip extending from a distal end of the middle tubular portion to a proximal end of the distal attachment leg; and 
 a tapered proximal portion extending from a proximal end of the middle tubular portion to a distal end of the proximal attachment leg, wherein the tapered proximal portion forms a taper angle relative to a longitudinal axis of the middle tubular portion; 
   a handle coupled with proximal ends of the outer shaft, the inner shaft, and the basket shaft, the handle comprising:
 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; and 
 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. 
   
     
     
         2 . The device of  claim 1 , wherein a longitudinal length of the tapered proximal portion is between two times and eight times longer than a length of the distal tip. 
     
     
         3 . The device of  claim 1 , wherein a total longitudinal balloon length of the distal tip, the middle tubular portion and the tapered proximal portion is five times greater than the expanded diameter of the middle tubular portion. 
     
     
         4 . The device of  claim 1 , wherein the taper angle of the tapered proximal portion relative to the longitudinal axis of the middle tubular portion is greater than or equal to 10 degrees and less than or equal to 15 degrees. 
     
     
         5 . The device of  claim 1 , wherein the inflatable balloon has a first thickness at the tapered proximal portion and a second thickness at the distal tip, and wherein the first thickness is greater than the second thickness. 
     
     
         6 . The device of  claim 1 , wherein the distal tip is rounded. 
     
     
         7 . The device of  claim 1 , wherein the distal tip is tapered. 
     
     
         8 . The device of  claim 1 , wherein the basket slider is independently moveable, relative to the inversion slider. 
     
     
         9 . The device of  claim 8 , further comprising an inversion slider lock within the handle, for locking the inversion slider to the handle to prevent its movement when the basket slider is being moved. 
     
     
         10 . The device of  claim 9 , wherein pushing down on the inversion slider unlocks the inversion slider from the inversion slider lock. 
     
     
         11 . The device of  claim 1 , wherein the inversion slider is located on a side surface of the handle, and wherein the basket slider is located on a top surface of the handle. 
     
     
         12 . The device of  claim 1 , wherein the basket slider is coupled with the inversion slider via a coupling, such that when the inversion slider is moved along the handle to invert the distal tip of the inflatable balloon, the basket slider automatically moves to keep the self-expanding wire basket closed around the urinary tract stone. 
     
     
         13 . The device of  claim 1 , wherein a space between the outer shaft and the inner shaft comprises an inflation lumen for the inflatable balloon, and wherein the handle further comprises a balloon infusion port in fluid communication with the inflation lumen. 
     
     
         14 . The device of  claim 1 , further comprising:
 a first hypotube attached to a proximal portion of the outer shaft; and   a second hypotube attached to a proximal portion of the inner shaft, wherein the second hypotube is configured to telescope within the first hypotube.   
     
     
         15 . The device of  claim 1 , wherein the outer shaft has an outer diameter of less than 1.2 mm. 
     
     
         16 . The device of  claim 1 , wherein the inflatable balloon comprises multiple, longitudinal pleats.