Catheter tip electrode assembly and method for fabricating same

Abstract

An electrode assembly for a sensor catheter tip includes a first electrode and a second electrode each having a central axis. The two electrodes are axially aligned and spaced apart along the axis. Each of the first and second electrodes comprises a contact aperture spaced from the center axis, and a contact. element positioned within each of the contact apertures. The center axis of each of the first and second electrodes is substantially aligned, and the contact elements corresponding to each of the first and second electrodes are offset, thereby providing staggered contact points for each respective electrode.

1 .- 16 . (canceled) 
   
   
       17 . A method of fabricating a catheter tip for an impedance spectroscopy system, the catheter tip including a plurality of electrodes with a dielectric material extending between adjacent electrodes, each of the electrodes including a contact aperture and at least one lead aperture, the electrodes electrically connected to respective contacts, said method comprising:
 press fitting one of the contacts to each of the electrodes via the respective contact apertures;   stacking the electrodes and attached contacts; and   rotating each electrode relative to the adjacent electrode in the stack so that the contacts are staggered from one another in the stack.   
   
   
       18 . A method in accordance with  claim 17  wherein the contacts have different lengths and each of the electrodes has a lead opening, said method further comprising arranging the electrodes such that each respective contact in the stack of electrodes extends through each of the respective lead openings of electrodes having a shorter contact in the stack. 
   
   
       19 . A method in accordance with  claim 17  further comprising injection molding the electrodes with a dielectric material, thereby forming dielectric spacer elements between the electrodes. 
   
   
       20 . A method in accordance with  claim 17  further comprising stacking dielectric spacer elements between each of the electrodes such that a positioning peg of each spacer element is received within at least one adjacent electrode. 
   
   
       21 . A method in accordance with  claim 18  further comprising attaching a lead to each respective contact. 
   
   
       22 . A method in accordance with  claim 18 , the assembly including a tip adjacent a first stacked electrode, said method further comprising overmolding a connector portion opposite the tip. 
   
   
       23 . A method in accordance with  claim 18  wherein said stacking the electrodes and attached contacts comprises stacking electrodes and dielectric spacer elements so that the spacer elements are sandwiched between the electrodes. 
   
   
       24 . A method in accordance with  claim 18  further comprising inserting a portion of the tip into the stacked electrodes, and overmolding the stacked electrodes to secure the tip to the electrodes. 
   
   
       25 . A method in accordance with  claim 18  wherein said press fitting one of the contacts to each of the electrodes via the respective contact apertures comprises press fitting a rim of a contact clip to the contact apertures, whereby a finger extending from the rim extends through the aperture. 
   
   
       26 . An electrode assembly for a sensor catheter tip, said assembly comprising:
 a first electrode and a second electrode, each electrode comprising a body having a center axis, each electrode comprising a contact point radially spaced from the center axis and radially offset with one another, each electrode comprising at least one aperture radially spaced from the center axis, the electrodes being axially aligned and spaced apart along the center axis; and   a contact element connected to each contact point, each contact element having fingers configured to be spread apart when mated with a lead wire such that the fingers engage, and are electrically coupled to, the corresponding contact point.   
   
   
       27 . An electrode assembly in accordance with  claim 26 , wherein said contact points of said first and second electrodes are offset approximately 90 degrees from one another. 
   
   
       28 . An electrode assembly in accordance with  claim 26 , wherein each of said first and second electrodes comprise a disk defined by multiple regions, said contact point positioned in one of said regions, the other of said regions comprising the aperture extending therethrough. 
   
   
       29 . An electrode assembly in accordance with  claim 26 , further comprising a dielectric spacer element disposed between said first and second electrodes. 
   
   
       30 . A catheter tip assembly for an impedance spectroscopy system, said assembly comprising:
 a rounded dielectric tip;   a first electrode disk adjacent said tip, said first electrode disk comprising a body having a contact aperture therethrough and a lead aperture therethrough, wherein the contact aperture is configured to receive a first contact by a press fit to electrically and mechanically couple the first contact to the first electrode disk;   a second electrode disk axially spaced from said first electrode disk, said second electrode comprising a body having a contact aperture therethrough and a lead aperture therethrough, wherein the contact aperture is configured to receive a second contact by a press fit to electrically and mechanically couple the second contact to the second electrode disk, wherein said second electrode disk is rotated relative to said first electrode disk about a longitudinal axis so that said contact aperture of said first electrode disk is axially aligned with said lead aperture of said second electrode disk; and   a dielectric spacer element positioned between said first and second electrode disks, said dielectric spacer element having at least one peg extending therefrom, the at least one peg being received within at least one of the first and second electrode disks.   
   
   
       31 . A catheter tip assembly in accordance with  claim 30 , wherein the dielectric spacer element includes a plurality of openings therethrough, the openings being aligned with the lead apertures and the contact apertures. 
   
   
       32 . A catheter tip assembly in accordance with  claim 30 , wherein each of the first and second electrode disks include positioning apertures, the at least one peg being received in the positioning aperture of the second electrode disk. 
   
   
       33 . A catheter tip assembly in accordance with  claim 30 , wherein the tip includes a positioning peg, the positioning peg of the tip being received within the first electrode disk to position the first electrode disk with respect to the first electrode disk. 
   
   
       34 . A catheter tip assembly in accordance with  claim 30 , further comprising a third electrode disk and a fourth electrode disk, said third and fourth electrode disks substantially identical to said first and second electrode disks, wherein each of said first, second, third and fourth electrode disks are circumferentially rotated relative to one another. 
   
   
       35 . A catheter tip assembly in accordance with  claim 30 , wherein the first and second contacts comprise a contact clip at an end thereof, said contact clip of each of said first and second contacts press fit into a respective one of said first and second contact apertures, one of said first and second contacts extending through a lead aperture in one of said first and second electrode disks. 
   
   
       36 . A catheter tip assembly in accordance with  claim 30 , further comprising first and second contacts inserted through said first and second contact apertures, each of said first and second contacts having a different axial length.