Cryosurgical instrument and its accessory system

Abstract

The invention proposes a cryosurgical instrument and its accessory system operating on the base of a refrigerant evaporation. The invention comprises combination of some technical solutions. Flow in a central lumen of the cryosurgical instrument has oscillating character; the refrigerant is provided on the internal surface of the distal cryotip in the form of separated portions. 2. The internal surface of the distal cryotip of the cryosurgical instrument is covered by a porous coating, which soaks completely one portion of the refrigerant. 3. Vapors obtained as a result of the refrigerant boiling on the porous coating of the cryotip are removed through the central lumen into the atmosphere. Combination of these technical solutions allows to construct a safely cryosurgical instrument with high freezing power and small outer diameter. The proposed cryosurgical instrument may be designed as a flexible cryocatheter or as a rigid cryoprobe.

1 . A method for cryogenic treatment of a patient, comprising:
 contacting a portion of the patient with a cryosurgical instrument, said instrument having a tip;   delivering a cryogenic liquid to said tip, wherein vapor is generated by boiling of said liquid;   separating said vapor from said liquid at said tip; and   exhausting said vapor.   
     
     
         2 . The method of  claim 1 , wherein said vapor is separated from said liquid by a porous coating on an internal surface at said tip. 
     
     
         3 . A method for cryogenic treatment of a patient, comprising:
 providing a cryosurgical instrument, said cryosurgical instrument receiving a cryogenic liquid; said cryosurgical instrument comprising a tip, said tip comprising a structure for separating said liquid from vapor by interfering with a flow of the cryogenic liquid;   delivering said cryogenic liquid to said tip;   separating said vapor from said liquid at said tip by said structure; and   exhausting said vapor.   
     
     
         4 . The method of  claim 3 , wherein said separating said vapor from said liquid further comprises increasing heat transfer to an internal surface of said tip by said structure. 
     
     
         5 . The method of  claim 3 , wherein said structure comprises a porous coating. 
     
     
         6 . A method for cryogenic treatment of a patient, comprising:
 providing a cryosurgical instrument, said cryosurgical instrument receiving a cryogenic liquid; said cryosurgical instrument comprising a tip and a structure for separating said liquid from vapor by interfering with a flow of the cryogenic liquid;   delivering said cryogenic liquid to said tip;   separating said vapor from said liquid by said structure; and   exhausting said vapor.   
     
     
         7 . The method of  claim 6 , wherein said structure comprises a porous coating. 
     
     
         8 . A method for cryogenic treatment of a patient, comprising:
 contacting a portion of the patient with a cryosurgical instrument, said instrument having a tip;   delivering a cryogenic mist to said tip, wherein vapor is generated by boiling of liquid in said mist;   separating said vapor from said liquid at said tip; and   exhausting said vapor.   
     
     
         9 . The method of  claim 8 , wherein said vapor is separated from said liquid by a porous coating on an internal surface at said tip. 
     
     
         10 . A method for cryogenic treatment of a patient, comprising:
 providing a cryosurgical instrument, said cryosurgical instrument receiving a cryogenic mist; said cryosurgical instrument comprising a tip and a structure for separating liquid in said mist from vapor by interfering with a flow of the cryogenic mist;   delivering said cryogenic mist to said tip;   separating said vapor from said liquid by said structure; and   exhausting said vapor.   
     
     
         11 . The method of  claim 10 , wherein said structure comprises a porous coating. 
     
     
         12 . The method of  claim 10 , wherein said structure is located in said tip. 
     
     
         13 . The method of  claim 12 , wherein said structure comprises a porous coating on an internal surface at said tip.