Miniature shredding tool for use in medical applications and methods for making

Abstract

The present invention relates generally to the field of micro-scale or millimeter scale devices and to the use of multi-layer multi-material electrochemical fabrication methods for producing such devices with particular embodiments relate to shredding devices and more particularly to shredding devices for use in medical applications. In some embodiments, tissue removal devices include tissue anchoring projections, improved blade configurations, and/or shields or shrouds around the cutting blades to inhibit outflow of tissue that has been brought into the device.

What is claimed is: 
     
         1 . A microscale or millimeter scale shredding tool for use in a medical procedure comprising:
 a. a housing having a distal end and a proximal end;   b. a first multi-blade blade stack mounted for rotational motion about a first axis relative to the housing and extending in part from the housing, wherein at least one of the blades of the first stack comprises a first and second side and a plurality of cutting tips wherein the maximum radial extension of the at least some of the tips are located on the first side of the blade while the maximum radial extension of the at least some other tips are located on the second side of the blade; and   c. a drive mechanism for rotating the blades of the first stack;
 wherein the shredding tool provides for intake and shredding of material encountered during the medical procedure 
   
     
     
         2 . The tool of  claim 1  additionally comprising:
 d. a second multi-blade blade stack mounted for rotational motion, about a second axis which is parallel to the first axis, relative to the housing and extending in part from the housing, wherein a least a portion of the blades of the second blade stack have interlaced positions with blades of the first stack in a plane perpendicular to the first and second axes of rotation but which are offset in the direction of the first and second axes so that the blades of first stack do not interfere with the blades of the second stack; and 
 e. a drive mechanism for rotating the blades of the second stack in an opposite direction relative to the rotation of the blades of the first stack. 
 
     
     
         3 . The tool of  claim 1  wherein the tips of the at least one blade of the first stack alternate between the first and the second side around a circumference of the at least one blade. 
     
     
         4 . The tool of  claim 2  wherein the first multi-blade blade stack comprises a plurality of first circular blades with first cutting elements extending from circumferences of the first circular blades,
 wherein the second multi-blade blade stack comprises a plurality of second circular blades with second cutting elements extending from circumferences of the second circular blades, 
 wherein each of the first circular blades rotates about a first common axis, 
 wherein each of the second circular blades rotates about a second common axis, 
 wherein the first circular blades each have a first thickness and a first gap relative to an immediate neighboring first circular blade, 
 wherein the second circular blades, each have a second thickness and a second gap relative to an immediate neighboring second circular blade, 
 wherein the first thickness relative to the second gap and the second thickness relative to the first gap, allows interlacing and movement of the first and second blades while providing for intake and shredding of material encountered by the blades during the medical procedure. 
 
     
     
         5 . The tool of  claim 1  wherein the tool comprises a plurality of stacked and adhered layers of deposited material. 
     
     
         6 . The tool of  claim 5  wherein the plurality of stacked and adhered layers of deposited material comprise electrodeposited material. 
     
     
         7 . A microscale or millimeter scale shredding tool for use in a medical procedure comprising:
 a. a housing having a distal end and a proximal end;   b. a first multi-blade blade stack mounted for rotational motion about a first axis relative to the housing and extending in part from the housing, wherein the housing includes a shroud that result in the first blade stacks being shielded around at least one half of its periphery to provide for reduced outflow of shredded material than if the shielding extended around less than one half their periphery; and   c. a drive mechanism for rotating the blades of the first stack; and
 wherein the shredding tool provides for intake and shredding of material encountered during the medical procedure. 
   
     
     
         8 . The tool of  claim 7  wherein the tool additionally comprising:
 d. a second multi-blade blade stack mounted for rotational motion, about a second axis which is parallel to the first axis, relative to the housing and extending in part from the housing, wherein a least a portion of the blades of the second blade stack have interlaced positions with blades of the first stack in a plane perpendicular to the first and second axes of rotation but which are offset in the direction of the first and second axes so that the blades of first stack do not interfere with the blades of the second stack; and 
 e. a drive mechanism for rotating the blades of the second stack in an opposite direction to that of the rotation of the blades of the first stack; and 
 wherein the shroud includes a plurality of shrouds that result in the first and second blades stacks being shielded around at least one half of their periphery to provide for reduced outflow of shredded material than if the shielding extended around less than one half their periphery. 
 
     
     
         9 . The tool of  claim 8 , wherein the first multi-blade blade stack comprises a plurality of first circular blades with first cutting elements extending from circumferences of the first circular blades,
 wherein the second multi-blade blade stack comprises a plurality of second circular blades with second cutting elements extending from circumferences of the second circular blades,   wherein each of the first circular blades rotates about a first common axis,   wherein each of the second circular blades rotates about a second common axis,   wherein the first circular blades each have a first thickness and a first gap relative to an immediate neighboring first circular blade,   wherein the second circular blades each have a second thickness and a second gap relative to an immediate neighboring second circular blade,   wherein the first thickness relative to the second gap and the second thickness relative to the first gap, allows interlacing and movement of the first and second blades while providing for intake and shredding of material encountered by the blades during the medical procedure.   
     
     
         10 . The tool of  claim 7  wherein the tool comprises a plurality of stacked and adhered layers of deposited material. 
     
     
         11 . The tool of  claim 10  wherein the plurality of stacked and adhered layers of deposited material comprise electrodeposited material. 
     
     
         12 . A microscale or millimeter scale shredding tool for use in a medical procedure comprising:
 a. a housing having a distal end and a proximal end wherein at least one position stabilizing mechanism extends from housing so to interact with tissue within a body of a patient to stabilize the position of the tool during shredding operations;   b. a first multi-blade blade stack mounted for rotational motion about a first axis relative to the housing and extending in part from the housing; and   c. a drive mechanism for rotating the blades of the first stack; and wherein the shredding tool provides for intake and shredding of material encountered during the medical procedure.   
     
     
         13 . The tool of  claim 12  wherein the tool additionally comprises:
 d. a second multi-blade blade stack mounted for rotational motion, about a second axis which is parallel to the first axis, relative to the housing and extending in part from the housing, wherein a least a portion of the blades of the second blade stack have interlaced positions with blades of the first stack in a plane perpendicular to the first and second axes of rotation but which are offset in the direction of the first and second axes so that the blades of first stack do not interfere with the blades of the second stack; and 
 e. a drive mechanism for rotating the blades of the second stack in an opposite direction relative to the rotation of the first stack of blades. 
 
     
     
         14 . The tool of  claim 12  wherein the stabilizing mechanism comprises a spike. 
     
     
         15 . The tool of  claim 14  wherein the spike comprises a plurality of spikes. 
     
     
         16 . The tool of  claim 13  wherein the first multi-blade blade stack comprises a plurality of first circular blades with first cutting elements extending from circumferences of the first circular blades,
 wherein the second multi-blade blade stack comprises a plurality of second circular blades with second cutting elements extending from circumferences of the second circular blades, 
 wherein each of the first circular blades rotates about a first common axis, 
 wherein each of the second circular blades rotates about a second common axis, 
 wherein the first circular blades each have a first thickness and a first gap relative to an immediate neighboring first circular blade, 
 wherein the second circular blades each have a second thickness and a second gap relative to an immediate neighboring second circular blade, 
 wherein the first thickness relative to the second gap and the second thickness relative to the first gap, allows interlacing and movement of the first and second blades while providing for intake and shredding of material encountered by the blades during the medical procedure. 
 
     
     
         17 . The tool of  claim 12  wherein the tool comprises a plurality of stacked and adhered layers of deposited material. 
     
     
         18 . The tool of  claim 17  wherein the plurality of stacked and adhered layers comprise electrodeposited material.