Intravascular temperature sensor

Abstract

Devices and methods for detecting vulnerable plaque within a blood vessel are disclosed. A catheter in accordance with the present invention includes an elongate shaft having a proximal end, a distal end, and an outer surface. At least one temperature sensor is disposed proximate to the distal end of the elongate shaft. In one preferred embodiment, the at least one temperature sensor is adapted to contact inner surface of the blood vessel. In another preferred embodiment, at least one temperature sensor is disposed within a channel defined by a body member that is disposed about the elongate shaft.

What is claimed is:  
     
         1 . A catheter for mapping vulnerable plaque deposits within a blood vessel, comprising; 
 an elongate shaft having a proximal end and a distal end;    at least one cowl fixed to the elongate shaft proximate the distal end thereof;    the at least one cowl defining an inlet port, an outlet port, and a flow channel extending therebetween; and    at least one temperature sensor disposed within the flow channel defined by the at least one cowl.    
     
     
         2 . The catheter of  claim 1 , wherein the at least one temperature sensor is adapted to measure the temperature of blood passing through the flow channel.  
     
     
         3 . The catheter of  claim 1 , wherein the at least one temperature sensor is adapted to measure the temperature of blood passing through the flow channel; and 
 the at least one cowl is configured such temperature of the blood passing through the flow channel is reflective of the temperature of inner surface of the blood vessel proximate the distal end of the catheter.    
     
     
         4 . The catheter of  claim 1 , wherein the temperature sensor comprises a resistance temperature device.  
     
     
         5 . The catheter of  claim 1 , wherein the temperature sensor comprises a thermocouple.  
     
     
         6 . The catheter of  claim 1 , wherein the temperature sensor comprises a thermistor.  
     
     
         7 . The catheter of  claim 1 , wherein the temperature sensor comprises a microbolometer.  
     
     
         8 . The catheter of  claim 1 , further comprising an interstitial member disposed between the at least one cowl and the elongate shaft.  
     
     
         9 . The catheter of  claim 1 , further comprising a balloon disposed between the at least one cowl and the elongate shaft.  
     
     
         10 . The catheter of  claim 1 , wherein the balloon has an inflated state and a deflated state.  
     
     
         11 . The catheter of  claim 1 , wherein the balloon is configured such that the flow of blood around the at least one cowl is precluded when the balloon is in the inflated state.  
     
     
         12 . The catheter of  claim 1 , wherein the balloon is configured such that the at least one cowl urged radially away from the elongate shaft when the balloon is in the inflated state.  
     
     
         13 . The catheter of  claim 1 , further comprising a plurality of cowls radially disposed about the elongate shaft.  
     
     
         14 . A catheter for mapping vulnerable plaque deposits within a blood vessel, comprising; 
 an elongate shaft having a proximal end and a distal end;    a plurality of cowls radially disposed about the elongate shaft proximate the distal end thereof;    each cowl defining an inlet port, an outlet port, and a flow channel extending therebetween; and    a temperature sensor disposed within each flow channel.    
     
     
         15 . The catheter of  claim 14 , wherein each temperature sensor comprises a resistance temperature device.  
     
     
         16 . The catheter of  claim 14 , wherein each temperature sensor comprises a thermocouple.  
     
     
         17 . The catheter of  claim 14 , wherein each temperature sensor comprises a thermistor.  
     
     
         18 . The catheter of  claim 14 , wherein each temperature sensor comprises a microbolometer.  
     
     
         19 . The catheter of  claim 14 , further comprising an interstitial member disposed between the cowls and the elongate shaft.  
     
     
         20 . The catheter of  claim 14 , further comprising a balloon disposed between the at least one cowl and the elongate shaft.  
     
     
         21 . The catheter of  claim 20 , wherein the balloon has an inflated state and a deflated state.  
     
     
         22 . The catheter of  claim 21 , wherein the balloon is configured such that the flow of blood around the cowls is precluded when the balloon is in the inflated state.  
     
     
         23 . The catheter of  claim 21 , wherein the balloon is configured such that the cowls urged radially away from the elongate shaft when the balloon is in the inflated state.  
     
     
         24 . A catheter for mapping vulnerable plaque deposits within a blood vessel, comprising; 
 an elongate shaft having a proximal end and a distal end;    an array of cowls radially disposed about the elongate shaft proximate the distal end thereof;    each cowl of the array of cowls defining an inlet port, an outlet port, and a flow channel extending therebetween;    a temperature sensor disposed within each flow channel; and    a means for radially expanding the array of cowls.    
     
     
         25 . The catheter of  claim 24 , wherein each temperature sensor comprises a resistance temperature device.  
     
     
         26 . The catheter of  claim 24 , wherein each temperature sensor comprises a thermocouple.  
     
     
         27 . The catheter of  claim 24 , wherein each temperature sensor comprises a thermistor.  
     
     
         28 . The catheter of  claim 24 , wherein each temperature sensor comprises a microbolometer.  
     
     
         29 . The catheter of  claim 24 , wherein the means for radially expanding the array of cowls comprises a hydraulic mechanism.  
     
     
         30 . The catheter of  claim 29 , wherein the means for radially expanding the array of cowls comprises a balloon.  
     
     
         31 . The catheter of  claim 30 , wherein the balloon is configured such that the flow of blood around the cowls is precluded when the balloon is in the inflated state.  
     
     
         32 . The catheter of  claim 24 , wherein the means for radially expanding the array of cowls comprises a mechanical mechanism.  
     
     
         33 . The catheter of  claim 29 , wherein the means for radially expanding the array of cowls comprises a plurality of resilient arms.