Guidewires for performing image guided procedures

Abstract

Guidewires and methods useable in conjunction with image guidance systems to facilitate performance of diagnostic or therapeutic tasks at locations within the bodies of human or animal subjects.

What is claimed is: 
     
         1 . A guidewire device for use with an image guidance system, said guidewire comprising:
 an elongate guidewire shaft having a proximal end and a distal end;   a sensor located on or in said shaft, said sensor being detectable by an image guidance system for real time determination of the location of the sensor within a subject's body;   first electrical contacts located on the shaft at or near its proximal end;   wires extending between the sensor and the contacts; and   a hub member that is disposable on and removable from the guidewire shaft, said hub member having second electrical contacts that electrically couple to said first electrical contacts when the hub member is disposed on said guidewire shaft.   
     
     
         2 . A guidewire according to  claim 1  wherein the hub member has a recess within which the proximal end of the guidewire is inserted. 
     
     
         3 . A guidewire device according to  claim 2  wherein the first electrical contacts are at spaced apart locations on a portion of the guidewire that becomes inserted into the recess and wherein the second electrical contacts are located within the recess at spaced apart locations such that the first and second contacts become electrically coupled when the proximal end of the guidewire is inserted into the recess. 
     
     
         4 . A guidewire device according to  claim 3  wherein the recess has an abutment surface against which the guidewire abuts to prevent further advancement of the guidewire into the recess. 
     
     
         5 . A guidewire device according to  claim 4  wherein the first and second contacts are spaced, relative to the abutment surface, such that when the guidewire is abutting against the abutment surface, the first and second contacts will be juxtapositioned and electrically coupled to one another. 
     
     
         6 . A guidewire device according to  claim 1  wherein the sensor is an electromagnetic coil located at or near the distal end of the guidewire shaft. 
     
     
         7 . A guidewire device according to  claim 6  wherein the electromagnetic coil is housed within a distal portion of the guidewire shaft. 
     
     
         8 . A guidewire device according to  claim 1  wherein the electromagnetic coil is positioned within a housing, said housing being positioned within the distal portion of the shaft. 
     
     
         9 . A guidewire device according to  claim 8  wherein the electromagnetic housing has a helical configuration. 
     
     
         10 . A guidewire device according to  claim 9  wherein the distal portion comprises a helical coil having a lumen extending therethrough and wherein the housing is screwed into the lumen of the helical coil. 
     
     
         11 . A guidewire device according to  claim 10  further comprising a plug member that closes the distal end of the lumen of the helical wire coil, distal to the housing. 
     
     
         12 . A guidewire device according to  claim 11  wherein the plug member is formed of substantially nonferromagnetic material. 
     
     
         13 . A guidewire device according to  claim 1  further comprising an outer cover on the distal portion of the guidewire shaft. 
     
     
         14 . A guidewire device according to  claim 13  wherein the outer cover is formed of substantially nonferromagnetic material. 
     
     
         15 . A guidewire device according to  claim 13  wherein the outer cover comprises heat shrunk plastic. 
     
     
         16 . A guidewire device according to  claim 13  wherein the outer cover is on the guidewire shaft from just distal the first electrical contacts to the distal tip and is a material selected from the group consisting of parylene, Teflon and silicone. 
     
     
         17 . A guidewire device according to  claim 1  wherein the guidewire shaft comprises a core wire having a distal portion, a mid-portion and a proximal portion, said sensor being located on or in the distal portion. 
     
     
         18 . A guidewire device according to  claim 17  wherein the first electrodes comprise proximal and distal electrode bands on the proximal portion of the guidewire shaft, said electrode bands being formed of electrically conductive material. 
     
     
         19 . A guidewire device according to  claim 18  further comprising insulator bands formed of material that is substantially electrically insulating, an insulator band being positioned on either side of each electrode band. 
     
     
         20 . A guidewire device according to  claim 17  wherein the distal portion is more flexible than the mid-portion.