Rotational Device with Eccentric Abrasive Element and Method of Use

Abstract

A rotational device for removing an occlusion from inside a tubular structure, the device comprising a drive shaft ( 10 ) for insertion over a guidewire into a tubular structure and an abrasive element ( 20 ) on the drive shaft having its centre of mass offset from a longitudinal axis of the drive shaft. A solid counterweight ( 30 D) is disposed on the drive shaft spaced from the abrasive element and having its centre of mass offset from the longitudinal axis of the drive shaft so that the abrasive element moves in an orbital path around said axis to abrade an occlusion from inside the tubular structure when the drive shaft rotates around the guidewire.

1 - 15 . (canceled) 
     
     
         16 . A rotational device, comprising:
 a drive shaft having a distal end section formed from at least one helically wound wire and an abrasive element on the distal end section having its centre of mass offset from a longitudinal axis of the drive shaft, and a solid counterweight on the distal end section spaced from the abrasive element and having its centre of mass offset from the longitudinal axis of the drive shaft.   
     
     
         17 . A rotational device according to  claim 16 , comprising two solid counterweights on the drive shaft. 
     
     
         18 . A rotational device according to  claim 17 , comprising a distal solid counterweight distal to the abrasive element on the drive shaft and, a proximal solid counterweight proximal to the abrasive element on the drive shaft. 
     
     
         19 . A rotational device according to  claim 18 , wherein the distance between the distal solid counterweight and the abrasive element and between the proximal solid counterweight and the abrasive element is substantially the same. 
     
     
         20 . A rotational device according to  claim 18 , wherein the distal solid counterweight is disposed on the distal end of the drive shaft. 
     
     
         21 . A rotational device according to  claim 18 , wherein the centre of mass of at least one of the solid counterweights is located in substantially the same longitudinal plane as the center of mass of the abrasive element. 
     
     
         22 . A rotational device according to  claim 18 , wherein the centre of mass of at least one of the solid counterweights is separated from the center of mass of the abrasive element by an angle of 180 degrees around the axis of the drive shaft. 
     
     
         23 . A rotational device according to  claim 18 , wherein at least one of the solid counterweights is substantially spherical in shape. 
     
     
         24 . A rotational device according to  claim 17 , wherein at least one of the solid counterweights is substantially half the weight of the abrasive element. 
     
     
         25 . A method of using a rotational device to remove an occlusion from inside a tubular structure, comprising the steps of:
 inserting a drive shaft with an abrasive element thereon over a guidewire into a tubular structure, the abrasive element having its center of mass offset from a longitudinal axis of the drive shaft; and   rotating the drive shaft over the guidewire so that a solid counterweight on the drive shaft having its center of mass offset from the longitudinal axis of the drive shaft causes the abrasive element to move in an orbital path around said axis to abrade an occlusion from inside the tubular structure.