Cryosurgical probe with vacuum insulation tube assembly

Abstract

A vacuum insulation tube assembly which is utilized as a component in a cryosurgical probe. The vacuum insulation tube assembly includes an inner tube; and, an outer tube concentrically positioned about the inner tube. The outer tube is securely soldered at end portions of the inner tube and forms a vacuum space between the inner tube and the outer tube. The vacuum tube assemblies may be conveniently mass produced using a special fixture.

1 . A vacuum insulation tube assembly for a cryosurgical probe, comprising:
 a) an inner tube; and,   b) an outer tube concentrically positioned about said inner tube and securely soldered thereto at first and second end portions of said inner tube to form a vacuum space between said inner tube and said outer tube.   
     
     
         2 . The vacuum insulation tube assembly of  claim 1 , further comprising a thermally insulative spacing element positioned between said inner tube and said outer tube. 
     
     
         3 . The vacuum insulation tube assembly of  claim 1 , further comprising an o-ring positioned adjacent to said first end portion. 
     
     
         4 . A method for manufacturing a vacuum insulation tube assembly for a cryosurgical probe, comprising the steps of:
 a) wrapping a thermally insulative spacing element around an inner tube and securely adhering said ceramic fiber to said inner tube;   b) sliding an outer tube over said inner tube and said spacing element, wherein said spacing element functions as a spacer therebetween;   c) sealably soldering a first end of said outer tube to a first end of said inner tube;   d) forming a vacuum space between said outer tube and said inner tube;   e) installing at least one o-ring over said inner tube near a second end of said outer tube to provide a sealing engagement with said outer tube; and,   f) sealably soldering a second end of said outer tube to a second end of said inner tube.   
     
     
         5 . A method for manufacturing a plurality of vacuum insulation tube assemblies for cryosurgical probes, comprising the steps of:
 a) providing a generally cylindrical vacuum chamber having an upper end, a lower end, and a central axis;   b) securely positioning a bottom plate within an interior volume of said vacuum chamber, at said lower end, said bottom plate comprising a plurality of spaced elongated bottom plate openings extending therethrough substantially parallel to said central axis;   c) securely positioning a support plate within an intermediate portion of said interior volume, said support plate comprising a plurality of spaced elongated support plate openings extending therethrough substantially parallel to said central axis;   d) inserting a plurality of precursor inner/outer tube assemblies through said support plate openings and into said bottom plate openings, each precurser inner/outer tube assembly comprising an outer tube concentrically positioned about an inner tube, each precursor inner/outer tube assembly being soldered at one end thereof;   e) securely positioning a guide plate assembly within said interior volume, at said upper end, said guide plate assembly comprising a plurality of spaced elongated guide plate openings extending therethrough substantially parallel to said central axis, said guide plate assembly being positioned to provide access to said precursor inner/outer tube assemblies through said spaced elongated guide plate openings;   f) installing a plurality of o-ring plunger assemblies into desired positions relative to associated spaced elongated guide plate openings;   g) mounting a cover assembly on said upper end of said vacuum chamber;   h) evacuating said vacuum chamber;   i) actuating said ejector plate assembly so as to push said o-ring plunger assemblies down, wherein o-rings engaged with said o-ring plunger assemblies are pushed down into desired positions between said outer tubes and inner tubes; and,   j) removing said cover assembly to allow removal of said precursor inner/outer tube assemblies; and,   k) soldering second ends of said precursor inner/outer tube assemblies to form completed vacuum insulation tube assemblies.   
     
     
         6 . The method of  claim 5 , wherein said step of wrapping a thermally insulative spacing element comprises wrapping ceramic fiber around said inner tube. 
     
     
         7 . A cryosurgical probe assembly, comprising:
 vacuum insulation tube assembly for a cryosurgical probe, comprising:   a) an inner tube; and,   b) an outer tube concentrically positioned about said inner tube and securely soldered thereto at first and second end portions of said inner tube to form a vacuum space between said inner tube and said outer tube.   
     
     
         8 . The cryosurgical probe assembly of  claim 7 , further comprising:
 a disposable probe assembly comprising said vacuum insulation tube assembly.   
     
     
         9 . The cryosurgical probe assembly of  claim 8 , wherein said disposable probe assembly comprises a stem and a fluid conduit subassembly bonded to said stem, said fluid conduit subassembly for delivering and returning cooling fluid used for cryogenic cooling, said fluid conduit subassembly including said vacuum insulation tube assembly. 
     
     
         10 . A detachable cryosurgical probe, comprising:
 a) a disposable probe assembly, comprising:
 i. a gas delivery assembly, comprising a stem and a fluid conduit subassembly bonded to said stem, said fluid conduit subassembly for delivering and returning cooling fluid used for cryogenic cooling, said fluid conduit subassembly including a vacuum insulation tube assembly, said vacuum insulation tube assembly, comprising: an inner tube; and an outer tube concentrically positioned about said inner tube and securely soldered thereto at first and second end portions of said inner tube to form a vacuum space between said inner tube and said outer tube; 
 ii. a finger lock element, comprising:
 1. a distal finger lock element section having a threaded inner surface for engagement with a threaded outer surface of said stem; and, 
 2. a plurality of radially spaced fingers extending proximally from said distal finger lock element section, each finger having a) a ramped surface for operatively engaging an associated ramp section on said stem during use; and, b) a female lip at a proximal end thereof; and, 
 
 iii. a disposable handle assembly, comprising:
 1. a proximal handle section having a distal end having an inner surface that is operatively engaged with an outer surface of said finger lock element so as to resist relative rotation and axial motion therebetween; 
 2. a distal handle section having an inner surface that is operatively engaged with another outer surface of said stem so as to resist relative rotation and axial motion therebetween; and, 
 3. a breakaway collar positioned between said proximal handle section and said distal handle section; and, 
 
   b) a reusable probe assembly, comprising:
 i. a manifold assembly for receiving a cryogenic working fluid and transmitting said cryogenic working fluid to said gas delivery assembly, said manifold assembly including a male lip at a distal end thereof; and, 
 ii. a reusable handle assembly secured about the periphery of said manifold assembly, wherein: 
   1) when the disposable probe assembly is attached, said breakaway collar is an integral unit which prevents relative rotation between said proximal handle section and said distal handle section, said female lip engaging said male lip, thereby securing said reusable probe assembly to said disposable probe assembly;   2) during an initial stage of detachment of said disposable probe assembly, the user rotates said distal handle section in a first direction relative to said proximal handle section to break away breakaway surfaces of said breakaway collar, allowing said breakaway collar to radially expand;   3) during an intermediate stage of detachment of said disposable probe assembly the user counter rotates said distal handle section in an opposite second direction relative to said proximal handle section the relative rotation between said proximal handle section and said distal handle section providing axial movement of said distal handle section toward said proximal handle section via said engagement of said threaded inner surface of said distal finger lock element section and said threaded outer surface of said stem, said axial movement being enabled by said radial expansion of said breakaway collar, said ramped surfaces of said radially spaced fingers engaging said associated ramp section on said stem during said axial movement thereby urging said fingers to open; and,   4) during a final stage of detachment said fingers open sufficiently to allow disengagement of said male lip from said female lip, thus enabling said disposable probe assembly to be detached from said reusable probe assembly,   wherein said vacuum insulation tube assembly is slideably engaged with an inner surface of said shaft and slideably engaged with said stem.