Cryoprobe for low pressure systems

Abstract

A cryoprobe for use in cryosurgery and other applications comprising a rigid outer tube, an inner coolant inlet tube a short rigid penetrating segment extending distally from the distal end of the outer tube and a helical-shaped baffle having a heating element disposed about the outer surface of the inlet tube. The baffle is adapted to produce turbulent fluid flow improving heat transfer and is able to warm target tissue during rapid freezing and thawing cycles.

1 . A device comprising: 
 a rigid outer tube;    a coolant inlet tube disposed within the outer tube;    a short rigid penetrating segment extending distally from a distal end of the outer tube;    and a helical-shaped baffle having a heating element disposed about a distal outer surface of the inlet tube, said baffle adapted to create turbulent fluid flow in fluid and force cryogen towards an inner surface of the outer rigid tube.    
   
   
       2 . The device of  claim 1  wherein the baffle and the heating element are unitary.  
   
   
       3 . The device of  claim 2  wherein the baffle comprises nichrome wire.  
   
   
       4 . The device of  claim 1  wherein the baffle comprises an extrusion, a machined part or a preformed wire.  
   
   
       5 . A device comprising: 
 a rigid outer tube having an inner diameter;    a coolant inlet tube disposed within the outer tube;    a short rigid penetrating segment extending distally from a distal end of the outer tube;    a helical-shaped baffle disposed about the inner diameter surface of the rigid outer tube; and    a heating element disposed within the distal section of the outer tube.    
   
   
       6 . A system for use in cryogenic surgery comprising: 
 a liquid nitrogen cryogen source; and    a cryoprobe in fluid communication with the cryogen source, said cryoprobe comprising a handle;    a rigid outer tube coupled to the handle;    a coolant inlet tube disposed within the outer tube in fluid communication with the liquid nitrogen source;    a short rigid penetrating segment extending distally from a distal end of the outer tube;    and a helical-shaped baffle adapted to create turbulent fluid flow in fluid having a heating element, said baffle disposed about a distal section of the inlet tube.