Methods and devices for detecting vulnerable plaque

Abstract

Devices and methods for detecting vulnerable plaque within a blood vessel are disclosed. A system in accordance with the present invention includes a first wire having a distal end coupled to a voltage source and a proximal end coupled to an instrument capable of measuring voltage. A distal end of a second wire is also coupled to the voltage source and a proximal end of the second wire is coupled to the instrument. The amplitude of the electromotive force produced by the voltage source preferably varies with the temperature of a tissue proximate the voltage source.

What is claimed is:  
     
         1 . A system for detecting vulnerable plaque within a blood vessel, comprising: 
 a first wire having a distal end and a proximal end;    a second wire having a distal end and an proximal end;    a voltage source coupled to the distal end of the first wire and the distal end of the second wire; and    a means for measuring voltage coupled to the proximal end of the first wire and the proximal end of the second wire.    
     
     
         2 . The system of  claim 1 , wherein an amplitude of the electromotive force produced by the voltage source varies with a temperature of the voltage source.  
     
     
         3 . The system of  claim 1 , wherein the voltage source comprises a photodiode.  
     
     
         4 . The system of  claim 1 , wherein the voltage source comprises a phototransistor.  
     
     
         5 . The system of  claim 1 , wherein the voltage source comprises a photovoltaic cell.  
     
     
         6 . The system of  claim 1 , wherein the voltage source comprises a thermocouple junction.  
     
     
         7 . An elongate medical device, comprising: 
 a first wire having a distal end and a proximal end;    a voltage source disposed proximate the distal end of the first wire; and    wherein the voltage source produces an electromotive force.    
     
     
         8 . The elongate medical device of  claim 7 , wherein an amplitude of the electromotive force varies with a temperature of the voltage source.  
     
     
         9 . The elongate medical device of  claim 7 , further including a second wire having a distal end and a proximal end.  
     
     
         10 . The elongate medical device of  claim 7 , further including a second wire having a distal end and a proximal end; and 
 the distal end of the second wire being coupled to the voltage source.    
     
     
         11 . The elongate medical device of  claim 7 , further including a second wire having a distal end and a proximal end; 
 the distal end of the second wire being coupled to the voltage source; and    the distal end of the first wire being coupled to the voltage source.    
     
     
         12 . The elongate medical device of  claim 7 , further including a second wire having a distal end and a proximal end, and an insulator disposed between the first wire and the second wire.  
     
     
         13 . The elongate medical device of  claim 7 , further including a sleeve disposed about the first wire.  
     
     
         14 . The elongate medical device of  claim 7 , wherein the voltage source comprises a thermocouple junction.  
     
     
         15 . An elongate medical device, comprising: 
 a first wire comprising a first material;    a second wire comprising a second material different from the first material;    a distal portion of the second wire being coupled to a distal portion of the first wire to form a junction; and    wherein the junction produces an electromotive force.    
     
     
         16 . The elongate medical device of  claim 1 , wherein an amplitude of the electromotive force varies with a temperature of the junction.  
     
     
         17 . The elongate medical device of  claim 1 , further including an insulator disposed between the first wire and the second wire.  
     
     
         18 . The elongate medical device of  claim 1 , further including a sleeve disposed about the first wire.  
     
     
         19 . The elongate medical device of  claim 1 , further including a second wire having a distal end and a proximal end, and an insulator disposed between the first wire and the second wire.  
     
     
         20 . The elongate medical device of  claim 1 , further including a second wire having a distal end and a proximal end, and a sleeve disposed about the first wire.