Thermal sensing device for thermal mapping of a body conduit

Abstract

The present invention relates to apparatus, systems, and methods utilizing cryogenic cooling in an angioplasty balloon catheter for treatment of arterial stenosis and prevention of restenosis. More particularly, the present invention relates to an angioplasty balloon catheter utilizing expansion of compressed gas to effect Joule-Thomson cooling of an angioplasty balloon, and optionally further incorporating external temperature sensors utilizable to identify a locus for treatment of arterial stenosis. The present invention further relates to angioplasty treatment systems incorporating such a catheter, and to cryogenic angioplasty methods for treating arterial stenosis and discouraging restenosis.

1 . A thermal sensing device designed and constructed to be spirally wrapped around a catheter insertable into a body conduit, said thermal sensing device having a distal end designed and constructed to be anchored to a distal portion of said catheter, said thermal sensing device comprising a plurality of thermal sensors mounted on a spring-like spiral base operable to expand away from said catheter, said expansion enhancing thermal contact between said thermal sensors and tissue of said body conduit, thereby enabling said thermal sensing device to report tissue temperatures along a selected length of said body conduit.  
     
     
         2 . The thermal sensing device of  claim 1 , designed and constructed to expand away from said catheter when a proximal end of said sensing device is pushed toward said anchored distal end of said sensing device.  
     
     
         3 . The thermal sensing device of  claim 1 , designed and constructed to contract towards said catheter when a proximal end of said sensing device is pulled away from said anchored distal end of said sensing device.  
     
     
         4 . An angioplasty balloon catheter comprising a moveable thermal sensor operable to report external temperatures along a selected length of said catheter, and thereby operable to report a temperature gradient along a selected segment of a body conduit when said catheter is inserted into said conduit and said sensor is moved along said catheter.  
     
     
         5 . The catheter of  claim 4 , wherein said moveable sensor is a fiber optic element moveable along said catheter and connectable to a thermographic camera external to said catheter.  
     
     
         6 . An angioplasty balloon catheter comprising a plurality of thermal sensors operable to report external temperatures along a selected length of said catheter, said catheter being operable to report a temperature gradient along a selected segment of a body conduit when said catheter is inserted into said body conduit.  
     
     
         7 . The catheter of  claim 6 , wherein said thermal sensors are selected from a group comprising a thermocouple sensor, a thermographic camera sensor, and a fiber-optic element connectable to a thermographic camera sensor external to said catheter.  
     
     
         8 . The catheter of  claim 6 , wherein said thermal sensors are arranged in a spiral configuration around and along a section of said catheter.  
     
     
         9 . The catheter of  claim 6 , further including a data communication element for communicating data generated by said thermal sensors to a data receiver outside of said catheter.  
     
     
         10 . The catheter of  claim 9 , wherein said data communication element comprises a wire.  
     
     
         11 . The catheter of  claim 9 , wherein said data communication element comprises a wireless communicator.  
     
     
         12 . The catheter of  claim 6 , wherein at least one of said plurality of thermal sensors comprises a hair-like fiber for enhancing transmission of heat between said at least one sensor and a body tissue adjacent to said sensor.  
     
     
         13 . The catheter of  claim 6  wherein said plurality of thermal sensors are distributed along an expandable spiral sensing loop having a distal end anchored to a distal portion of said catheter, said sensing loop being spirally wound around a section of shaft of said catheter and being operable to expand away from said shaft, thereby enhancing thermal communication between said sensors distributed along said sensing loop and body tissues adjacent to said catheter.  
     
     
         14 . The catheter of  claim 13 , wherein said spiral sensing loop is designed and constructed to expand away from said shaft of said catheter when a proximal end of said sensing loop is pushed toward said anchored distal end of said sensing loop.  
     
     
         15 . The catheter of  claim 13 , wherein said spiral sensing loop is designed and constructed to contract toward said shaft of said catheter when a proximal end of said sensing loop is pulled away from said anchored distal end of said sensing loop.