Modular sensing guidewire

Abstract

A sensing guidewire device used to measure physiological parameters within a living body. In one embodiment, the device is used to measure the fractional flow reserve (FFR) across a stenotic lesion in a patient's vasculature. The device includes a sensor that is adapted to be affixed near the distal end of a guidewire. The guidewire contains a corewire, processed to enclose electrical conductors in a sealed, off-centered interstice or channel, with an outer diameter approximate to the outer diameter of the device, running substantially the full length of the device, and has a homogenous outer surface. The enclosed eccentric channel provides space for electrical conductors to move freely. The corewire can have a tapered segment to create desirable flexibility. A solid connector comprised of alternating conductive and insulating elements for connecting the conductors to an external device is disclosed. The guidewire can be advanced through a patient's blood vessels, returning pressure measurements across vessel blockages that allow for accurate assessment of blockage severity and lead to better clinical outcomes.

1 - 14 . (canceled) 
     
     
         15 . A method for manufacturing a sensing guidewire device for measuring physiological parameters in a living body comprising the steps of:
 drawing a stainless steel wire through a die;   forming in the resulting cold drawn corewire a closed internal channel having a cross-sectional configuration which is off-set from a central axis of the corewire and has a sufficient size to enable free movement of a conducting wire positioned within the closed internal channel;   feeding the conducting wire through the closed internal channel of the corewire; and   ensuring the length of the conducting wire is slidable within the channel.   
     
     
         16 . The method of  claim 15 , wherein the step of forming a cold drawn corewire further comprises the step of:
 closing the closed internal channel using a metal strip bonded to the corewire during drawing of the wire through the die.   
     
     
         17 . The method of  claim 16 , further comprising the step of:
 post-processing the cold drawn corewire to remove excess metal strip material from the corewire to ensure a uniform external diameter.   
     
     
         18 . The method of  claim 15 , wherein the step of drawing a stainless steel wire through a die further comprises the step of:
 surrounding the stainless steel wire with a metal tubular sleeve which is simultaneously drawn through the die to substantially engage an outer diameter of the stainless steel wire with an inner diameter of the tubular sleeve, while maintaining the closed internal channel to enable free movement of a conducting wire positioned within the closed internal channel.   
     
     
         19 . The method of  claim 18 , further comprising the step of:
 post-processing the cold drawn corewire to remove excess metal tubular sleeve material from the corewire and maintaining a sealed closed internal channel and a uniform external diameter.