Abstract:
A cryogenic wand for ablating tissue comprising a cryogenic ablation tube closed at a distal end and including an ablation zone, the ablation tube in fluid communication with and coupled proximally to at least one of two segments that are rotatably repositionable with respect to one another, wherein the two segments are fluidically sealed so that fluid entering a first of the at least two segments passes therethrough and enters a second of the at least two segments.

Description:
RELATED ART 
     Field of the Invention 
       [0001]    The present disclosure is directed to cryogenic probes and, more specifically, to cryogenic probes that are rotationally repositionable. 
       INTRODUCTION TO THE INVENTION 
       [0002]    It is a first aspect of the present invention to provide a cryogenic wand for ablating tissue comprising a cryogenic ablation tube closed at one end, the ablation tube in fluid communication with at least two segments that are rotatably repositionable with respect to one another, wherein the two segments are fluidically sealed so that fluid entering a first of the at least two segments passes therethrough and enters a second of the at least two segments. 
         [0003]    In a more detailed embodiment of the first aspect, a swivel interposes the at least two segments. In yet another more detailed embodiment, the swivel circumscribes a stationary cryogenic feed conduit supplying fresh cryogenic fluid to the cryogenic ablation tube. In a further detailed embodiment, the cryogenic ablation tube includes a thermocouple. In still a further detailed embodiment, the swivel comprises: (a) a first swivel section defining a first longitudinal cavity extending therethrough, (b) a second swivel section defining a second longitudinal cavity extending therethrough and, (c) a first seal circumscribing at least a portion of the first swivel section and inscribing at least a portion of the second swivel section to form a seal between the first and second swivel sections. In more detailed embodiment, the first longitudinal cavity is in series with the second longitudinal cavity. In a more detailed embodiment, an interior surface defining the first longitudinal cavity also defines a portion of a cryogenic fluid exhaust conduit, an interior surface defining the second longitudinal cavity also defines a portion of the cryogenic fluid exhaust conduit and, the portions of the cryogenic fluid exhaust conduit defined by the first and second longitudinal cavities circumscribe a portion of a cryogenic feed conduit. In another more detailed embodiment, the first longitudinal cavity is coaxial with the second longitudinal cavity, and the first and second longitudinal cavities are at least partially occupied by a cryogenic feed conduit. In yet another more detailed embodiment, the swivel comprises: (a) a first swivel section defining a first longitudinal cavity extending therethrough, (b) a second swivel section defining a second longitudinal cavity extending therethrough, (c) a sleeve concurrently circumscribing at least a portion of the first swivel section and a portion of the second swivel section, and (d) a seal interposing the sleeve and at least one of the first swivel section and the second swivel section. In still another more detailed embodiment, the first swivel section includes a first circumferential recess, the second swivel section includes a second circumferential recess, the sleeve is cylindrical and concurrently circumscribes the first circumferential recess and the second circumferential recess, the seal includes a first O-ring seated within the first circumferential recess to interpose the sleeve and the first swivel section to seal therebetween, and the seal includes a second O-ring seated within the second circumferential recess to interpose the sleeve and the first swivel section to seal therebetween. 
         [0004]    In yet another more detailed embodiment of the first aspect, the first swivel section includes a first cylindrical portion, the second swivel section includes a second cylindrical portion, the sleeve houses both the first and second cylindrical portions, and an insulated housing circumscribes the sleeve, the first cylindrical portion, and the second cylindrical portion. In still another more detailed embodiment, the wand further comprises a diverter in fluid communication with the cryogenic ablation tube, the diverter including: (a) a first fitting accommodating an outgoing cryogenic feed conduit and an incoming cryogenic exhaust conduit, (b) a second fitting accommodating an incoming cryogenic feed conduit, and (c) a third fitting accommodating an outgoing cryogenic exhaust conduit, where the second fitting is sealed off from the third fitting. In a further detailed embodiment, the first fitting is operatively coupled to at least one of the at least two segments that are rotatably repositionable with respect to one another. In still a further detailed embodiment, the diverter is positioned within an insulated housing, where the insulating housing includes a first orifice receiving at least two coaxial conduits, where a first of the at least two coaxial conduits is an outgoing cryogenic feed conduit, and where a second of the at least two coaxial conduits is incoming cryogenic exhaust conduit. In a more detailed embodiment, the insulating housing includes a second orifice receiving at least one of an incoming cryogenic feed conduit and an outgoing cryogenic exhaust conduit. In a more detailed embodiment, an incoming cryogenic feed conduit enters the insulating housing and an outgoing cryogenic exhaust conduit leaves the insulating housing, and the incoming cryogenic feed conduit and the outgoing cryogenic exhaust conduit are not coaxially oriented with respect to one another. In another more detailed embodiment, the wand further comprises a robotic appendage coupled to the cryogenic ablation tube in order to facilitate grasping by robotic jaws. In yet another more detailed embodiment, the robotic appendage includes a collar that circumscribes cryogenic ablation tube. 
         [0005]    In a more detailed embodiment of the first aspect, the collar defines a longitudinal cavity occupied by at least a portion of the cryogenic ablation tube and an adapter to couple the cryogenic tube to at least one of the at least two segments that are rotatably repositionable with respect to one another. In yet another more detailed embodiment, the wand further comprises an integrated diverter and swivel assembly that interposes the at least two segments that are rotatably repositionable with respect to one another, wherein a first of the at least two segments includes at least two separate conduits for carrying cryogenic feed fluid and exhausted cryogenic fluid, wherein a second of the at least two segments includes at least two separate conduits for carrying the cryogenic feed fluid and the exhausted cryogenic fluid. In a further detailed embodiment, the first of the at least two segments comprises a first swivel section, the second of the at least two segments comprises a second swivel section, the integrated diverter and swivel assembly includes a first seal circumscribing at least a portion of the first swivel section and inscribing at least a portion of the second swivel section to form a seal between the first and second swivel sections. In still a further detailed embodiment, the at least two separate conduits for carrying cryogenic feed fluid and exhausted cryogenic fluid of the first segment are coaxially oriented with respect to one another. In a more detailed embodiment, the at least two separate conduits for carrying cryogenic feed fluid and exhausted cryogenic fluid of the second segment are not coaxially oriented with respect to one another. In a more detailed embodiment, the first of the at least two segments comprises a first swivel section, the second of the at least two segments comprises a second swivel section, the integrated diverter and swivel assembly includes a sleeve concurrently circumscribing at least a portion of the first swivel section and a portion of the second swivel section, the integrated diverter and swivel assembly includes a seal interposing the sleeve and at least one of the first swivel section and the second swivel section. In another more detailed embodiment, the at least two separate conduits for carrying cryogenic feed fluid and exhausted cryogenic fluid of the first segment are coaxially oriented with respect to one another. In yet another more detailed embodiment, the at least two separate conduits for carrying cryogenic feed fluid and exhausted cryogenic fluid of the second segment are not coaxially oriented with respect to one another. In still another more detailed embodiment, the first swivel section includes a first circumferential recess, the second swivel section includes a second circumferential recess, the sleeve is cylindrical and concurrently circumscribes the first circumferential recess and the second circumferential recess, the seal includes a first O-ring seated within the first circumferential recess to interpose the sleeve and the first swivel section to seal therebetween, and the seal includes a second O-ring seated within the second circumferential recess to interpose the sleeve and the first swivel section to seal therebetween. In yet another more detailed embodiment, the first swivel section includes a first cylindrical portion, the second swivel section includes a second cylindrical portion, the sleeve houses both the first and second cylindrical portions, an insulated housing circumscribes the sleeve, the first cylindrical portion, and the second cylindrical portion. 
         [0006]    It is a second aspect of the present invention to provide a cryogenic probe for ablating tissue comprising: (a) an elongated tube open at one end and closed at an opposite end, the elongated tube operatively coupled to at least two segments that are rotatably repositionable with respect to one another using an in-series swivel, wherein the two segments are sealed to inhibit fluid passing between the at least two segments, the elongated tube defining an internal cavity; and, (b) at least one cryogenic fluid supply line occupying at least a portion of the internal cavity of the elongated tube, the at least one cryogenic fluid supply line including a nozzle for introducing cryogenic fluid into the internal cavity of the elongated shell. 
         [0007]    In a more detailed embodiment of the second aspect, the at least one cryogenic fluid supply line includes at least two sections that are rotatably repositionable with respect to one another. In yet another more detailed embodiment, the elongated tube includes a wall thickness of from about 0.020 inches to 0.035 inches. In a further detailed embodiment, the elongated tube includes an outside diameter of from about 0.16 inches to about 0.20 inches. In still a further detailed embodiment, the cryogenic probe further comprises a swivel interposing the at least two segments. In a more detailed embodiment, the cryogenic probe further comprises a diverter in fluid communication with the elongated tube, the diverter including: (a) a first fitting accommodating an outgoing cryogenic feed conduit and an incoming cryogenic exhaust conduit, (b) a second fitting accommodating an incoming cryogenic feed conduit, and (c) a third fitting accommodating an outgoing cryogenic exhaust conduit, where the second fitting is sealed off from the third fitting. In a more detailed embodiment, the cryogenic probe further comprises a thermocouple mounted to the elongated tube. In another more detailed embodiment, the cryogenic probe further comprises a metallic coil housed within the elongated tube. 
         [0008]    It is a third aspect of the present invention to provide a cryogenic probe for ablating tissue comprising: (a) an ablator comprising an ablation tube closed at one end and occupied by a cryogenic feed tube having an orifice, where an interior surface of the ablator at least partially defines a cryogenic exhaust conduit, where the ablation tube includes a wall thickness of from about 0.020 inches to 0.035 inches, and where the ablation tube includes an outside diameter of from about 0.16 inches to about 0.20 inches; and, (b) a swivel operatively coupled to the ablator to allow the ablation tube to rotate about the cryogenic feed tube. 
         [0009]    It is a fourth aspect of the present invention to provide a method of fabricating a cryogenic wand for ablating tissue, the method comprising: (a) forming a cryogenic ablation tube closed at one end; (b) operatively coupling the cryogenic ablation tube to a swivel, where the swivel interposes the closed end of the cryogenic ablation tube and a conduit adapted to carry at least one feed cryogenic fluid proximate the closed end of the cryogenic ablation tube and exhaust cryogenic fluid returning from proximate the closed end of the cryogenic ablation tube. 
         [0010]    In a more detailed embodiment of the fourth aspect, the method further includes the act of inserting a cryogenic feed conduit within the swivel so the swivel circumscribes the cryogenic feed conduit. In yet another more detailed embodiment, the method further includes the act of inserting mounting a thermocouple to the cryogenic ablation tube. In a further detailed embodiment, the swivel comprises: (a) a first swivel section defining a first longitudinal cavity extending therethrough; (b) a second swivel section defining a second longitudinal cavity extending therethrough; and, (c) a first seal circumscribing at least a portion of the first swivel section and inscribing at least a portion of the second swivel section to form a seal between the first and second swivel sections. In still a further detailed embodiment, the first longitudinal cavity is in series with the second longitudinal cavity. In a more detailed embodiment, an interior surface defining the first longitudinal cavity also defines a portion of a cryogenic fluid exhaust conduit, an interior surface defining the second longitudinal cavity also defines a portion of the cryogenic fluid exhaust conduit, and the portions of the cryogenic fluid exhaust conduit defined by the first and second longitudinal cavities circumscribe a portion of a cryogenic feed conduit. In a more detailed embodiment, the first longitudinal cavity is coaxial with the second longitudinal cavity, and the first and second longitudinal cavities are at least partially occupied by a cryogenic feed conduit. In yet another more detailed embodiment, the swivel comprises: (a) a first swivel section defining a first longitudinal cavity extending therethrough; (b) a second swivel section defining a second longitudinal cavity extending therethrough; a sleeve concurrently circumscribing at least a portion of the first swivel section and a portion of the second swivel section; and, (d) a seal interposing the sleeve and at least one of the first swivel section and the second swivel section. In still another more detailed embodiment, the first swivel section includes a first circumferential recess, the second swivel section includes a second circumferential recess, the sleeve is cylindrical and concurrently circumscribes the first circumferential recess and the second circumferential recess, the seal includes a first O-ring seated within the first circumferential recess to interpose the sleeve and the first swivel section to seal therebetween, and the seal includes a second O-ring seated within the second circumferential recess to interpose the sleeve and the first swivel section to seal therebetween. 
         [0011]    In yet another more detailed embodiment of the fourth aspect, the first swivel section includes a first cylindrical portion, the second swivel section includes a second cylindrical portion, the sleeve houses both the first and second cylindrical portions, an insulated housing circumscribes the sleeve, the first cylindrical portion, and the second cylindrical portion. In still another more detailed embodiment, the method further includes the act of operatively coupling a diverter to the swivel, the diverter including: (a) a first fitting accommodating an outgoing cryogenic feed conduit and an incoming cryogenic exhaust conduit, (b) a second fitting accommodating an incoming cryogenic feed conduit, and (c) a third fitting accommodating an outgoing cryogenic exhaust conduit, where the second fitting is sealed off from the third fitting. In a further detailed embodiment, the first fitting is operatively coupled to at least one of the at least two segments that are rotatably repositionable with respect to one another. In still a further detailed embodiment, the diverter is positioned within an insulated housing, where the insulating housing includes a first orifice receiving at least two coaxial conduits, where a first of the at least two coaxial conduits is an outgoing cryogenic feed conduit, and where a second of the at least two coaxial conduits is incoming cryogenic exhaust conduit. In a more detailed embodiment, the insulating housing includes a second orifice receiving at least one of an incoming cryogenic feed conduit and an outgoing cryogenic exhaust conduit. In a more detailed embodiment, an incoming cryogenic feed conduit enters the insulating housing and an outgoing cryogenic exhaust conduit leaves the insulating housing, and the incoming cryogenic feed conduit and the outgoing cryogenic exhaust conduit are not coaxially oriented with respect to one another. 
         [0012]    In yet another more detailed embodiment of the fourth aspect, the method further comprises the act of mounting a robotic appendage to the cryogenic ablation tube in order to facilitate grasping by robotic jaws. In still another more detailed embodiment, the robotic appendage includes a collar that circumscribes cryogenic ablation tube. In a further detailed embodiment, the collar defines a longitudinal cavity occupied by at least a portion of the cryogenic ablation tube and an adapter to couple the cryogenic tube to at least one of the at least two segments that are rotatably repositionable with respect to one another. In still a further detailed embodiment, the swivel comprises an integrated diverter and swivel assembly, wherein the integrated diverter and swivel assembly is operative to take an input of two coaxial conduits and create an output of two non-coaxial conduits. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a schematic diagram of a first exemplary cryogenic probe in accordance with the instant disclosure. 
           [0014]      FIG. 2  is a cross-sectional view of the exemplary diversion section of  FIG. 1 . 
           [0015]      FIG. 3  is a cross-sectional view of the exemplary swivel section of  FIG. 1 . 
           [0016]      FIG. 4  is a cross-sectional view of the exemplary tool attachment section of  FIG. 1 . 
           [0017]      FIG. 5  is a schematic diagram of a second exemplary cryogenic probe in accordance with the instant disclosure. 
           [0018]      FIG. 6  is a cross-sectional view of the exemplary swivel section of  FIG. 5 . 
           [0019]      FIG. 7  is a cross-sectional view of the exemplary diversion section of  FIG. 5 . 
           [0020]      FIG. 8  is a schematic diagram of a third exemplary cryogenic probe in accordance with the instant disclosure. 
           [0021]      FIG. 9  is a cross-sectional view of the exemplary integrated swivel diverter assembly of  FIG. 8 . 
           [0022]      FIG. 10  is a magnified view of the portion identified  9 - 9  in  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    The exemplary embodiments of the present disclosure are described and illustrated below to encompass cryogenic surgical instruments and, more particularly, to cryogenic probes or cryoprobes incorporating at least one swivel and used for creating lines of ablation on tissue such as, for example, for the treatment of cardiac arrythmias including atrial fibrillation. Of course, it will be apparent to those of ordinary skill in the art that the embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present disclosure. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present disclosure. Hereinafter, the exemplary embodiments of the present disclosure will be described with reference to the drawings. 
         [0024]    With reference to  FIGS. 1 and 2 , a first exemplary cryogenic probe  100  includes a wand  102  coupled to an umbilical tether  104  in order to supply cryogenic fluid from a fluid reservoir  106  to the wand. In this first exemplary embodiment, the flow of cryofluid to and from the cryogenic probe  100  is controlled from a separate, commercially available console  108  that regulates and controls the pressure of the cryofluid introduced into the cryogenic wand  102 . The console  108  is capable of pressurizing the wand  102  for active defrost and provides for appropriate discharge of expanded cryofluid exhaust. Alternatively, or in addition, hand controls (not shown) may be associated with the cryogenic probe  100  to regulate and control the pressure of the cryofluid introduced into the cryogenic wand  102 . In this first exemplary embodiment, the wand  102  includes a diversion section  110 , a swivel section  112 , and a tool attachment section  114  along the length thereof. 
         [0025]    Referring to  FIGS. 1 and 2 , the diversion section  110  operates to delineate between the coaxial section  120  and the parallel section  122  by housing a diverter  124  operative to provide coaxial flow of the feed and exhaust cryogenic fluid on one side and non-coaxial flow of the exhaust and feed cryogenic fluid on the opposite side. As used herein, the term “diverter” means an apparatus operative to take at least two non-circumscribing conduits and redirects at least one of the conduits so that a first of the conduits at least partially circumscribes at least a second of the conduits. In the parallel section  122 , the exhausted cryogenic fluid is carried away from the ablation end (i.e., distal end) by a separate exhaust conduit  126 ′, while incoming cryogenic fluid (approximate a proximal end) is carried toward the ablation end by a feed line  128 ′ that is not coaxial with the exhaust conduit  126 . But on the opposite side of the diverter  124 , a feed conduit  128  carrying cryogenic fluid and the exhaust conduit  126  are coaxial, with the exhaust cryogenic fluid flowing over the outside of the feed conduit. 
         [0026]    The diverter  124  comprises a cryogenic feed barb fitting  132  that includes a smooth cylindrical cavity sized to receive the cryogenic feed conduit  128  and create a friction fit therewith. In this exemplary embodiment, the proximal end  134  of the barb fitting  132  marks the origination point of the cryogenic feed conduit  128 , while the feed line  128 ′ in communication by the cryogenic fluid tank extends distally past the proximal end to circumscribe the barb fitting  132 . The barb fitting  132  includes three barbs characterized by an inclined face (from proximal to distal) and a vertical wall intersecting the inclined face. The inclined faces  136  provide a conical profile that allows the feed line to more easily circumscribe the fitting  132  and be repositioned distally, while the vertical walls  138  retard proximal movement of the feed line after the feed line is installed around the fitting. The barb fitting  132  is an integral part of a diverter body  140  having a longitudinal cavity through which the feed conduit  128  extends. The profile of the longitudinal cavity  142  changes from proximal to distal, with the distal portion being sized only to accommodate the cryogenic feed conduit  128 , but moving distally, the profile increases. 
         [0027]    The diverter body  140  includes a T-fitting  144  that operates to change the profile of the longitudinal cavity  142 . The base section  146  of the T-fitting  144 , which extends perpendicularly with respect an adapter section  148  and is in fluid communication therewith, is circumscribed by a branch conduit  150  having its own barb fitting  152  at the proximal end thereof. This barb fitting  152  is similar to the barb fitting  132  discussed above in terms of having inclined faces to provide a conical profile that allows the separate exhaust conduit  126 ′ to more easily circumscribe the fitting  152  and vertical walls to retard proximal movement of the separate exhaust conduit after the separate exhaust conduit is installed around the fitting  152 . In exemplary form, the branch conduit  150  is at least one of welded, brazed, and soldered to the base section  146  to ensure a fluid tight seal therebetween. 
         [0028]    In order to divert the exhaust cryogenic fluid through the branch conduit  150 , the adapter section  148  is sealed at its proximal end and is large enough to provide a circumferential gap  154  between the interior of the branch conduit and the exterior of the feed conduit  128 . This circumferential gap provides a pathway for exhaust cryogenic fluid passing from the exhaust conduit  126  to reach the base section  146 , flow into the branch conduit  150 , and ultimately flow into the separate exhaust conduit  126 ′. 
         [0029]    In order to mount the exhaust conduit  126  to the diverter body  140 , the diverter body includes a distal barb fitting  156  extending from, and in fluid communication with, the adapter section  148 . The barb fitting  156  is received within the distal portion of the adapter section  148  and create a friction fit therebetween to retain the fitting. However, in this exemplary embodiment, the fitting is at least one of welded, brazed, and soldered to the adapter section  148  to ensure a fluid tight seal therebetween. The distal portion of the barb fitting  156  includes at least one barb, similar to those discussed above, in order to be circumscribed by the exhaust conduit  126  and retard distal movement of the exhaust conduit away from the barb fitting. Though not necessarily required, the exhaust conduit  126  may be at least one of welded, brazed, and soldered to the barb fitting  156  to ensure a fluid tight seal therebetween. 
         [0030]    The diverter  124  is seated within a housing  160  comprised of complementary halves. It is to be understood, however, that the housing may be a single piece, such as an injection molded jacket. The housing  160  includes two openings  162 ,  164  oriented at opposite ends of the housing, with the larger of the two openings  162  located at a proximal end of the housing and allowing throughput of both the separate exhaust conduit  126 ′ and separate feed conduit  128 ′, whereas the smaller of the two openings  164  at the distal end of the housing allows throughput of the coaxial conduits  126 ,  128 . The interior of the housing  160  includes a series of ribs  166 ,  168 ,  170  that protrude from an interior surface and operate to align the diverter  124  and conduits  126 ,  128 ,  126 ′,  128 ′. Distal from the diversion section  110  is the swivel section  112 . 
         [0031]    Referring to  FIGS. 1 and 3 , the swivel section  112  includes a swivel  180  so that the proximal and distal sections  182 ,  184  of the exhaust conduit  128  can rotate with respect to one another. In this exemplary embodiment, the swivel  180  includes a proximal component  186  and a distal component  188  that are rotationally repositionable with respect to one another. Each component  186 ,  188  includes a longitudinal passage  190  defined by a series of interior surfaces of the components that accommodates throughput of the feed conduit  128 , but is also large enough to accommodate a separate stream of exhaust cryogenic fluid. More specifically, the interior circumferential surface of the feed conduit  128  provides a sealed delivery mechanism for the cryogenic fluid delivered from the cryogenic fluid tank. At the same time; the interior surfaces of the components  186 ,  188  cooperate with the exterior surface of the feed conduit  128  to define a sealed delivery mechanism for the exhausted cryogenic fluid. 
         [0032]    The distal component  188  includes an integrally formed barb fitting  192  having a circular opening  194  that leads into a cylindrical cavity bounded by an interior surface  196  having a substantially constant diameter. The circular opening  194  is defined by a circular lip  198  that transitions into the exterior surface  200  of the barb fitting  192 . This exterior surface  200  is characterized by a circular cross-section that, unlike the interior surface  196 , changes to taper outward from the lip  198  to increase its diameter. This tapered section  202  increases in diameter until terminating at a vertical step  204  to form the barb. This vertical step  204  operates to retard the distal section  184  of the exhaust conduit from substantial distal movement that would remove the conduit from the barb fitting  192 . Beyond the barb, traveling proximally, the exterior surface includes a substantially cylindrical, constant diameter section  206  that extends to reach a second vertical step  208 . This second vertical step  208  is adjacent to a constant diameter section  210  that is adjacent to a conical section  212  having a diameter that increases (distal to proximal), which is itself adjacent to another constant diameter section  214  marking the maximum widthwise dimension of the swivel  180 . Immediately proximal to this constant diameter section  214  is a vertical wall  216  that marks the transition for the portion of the exterior surface  200  of the distal component  188  that interfaces with the interior surfaces  128  of the proximal component  186 . 
         [0033]    In order to resist longitudinal motion of the components  186 ,  188  away from one another, the proximal component  186  includes a circumferential end flange  220  that is received within a circumferential groove  222  of the distal component. This circumferential flange  220  is tapered on its distal end (i.e., leading edge) in order to pass over a plateau  224  that extends circumferentially beyond an external barrel surface  226 . One side of the plateau  224  is joined to the vertical wall  216  by a recessed wall  228  that all cooperate to define the groove  222 . In order to retain the circumferential end flange  220  within the circumferential groove  222 , the backside  230  of the flange is vertical so that the backside is parallel to the front side of the plateau  224  defining the groove. The interior surface  128  of the proximal component  186  partially defines a pair of circumferential cavities  232 ,  234  in which at least one seal ring is located. 
         [0034]    In this exemplary embodiment, the first circumferential cavity  232  has a trapezoidal cross-section, but is unoccupied by a seal ring. However, in an alternate exemplary embodiment, the cavity  232  may be occupied by one or more seal rings. The second circumferential cavity  234  has a rectangular cross-section cooperatively defined by the backside of the plateau  224 , the barrel surface  226 , and the interior surface  128  extending in parallel to the barrel surface. In exemplary form, the second circumferential cavity  234  is at least partially occupied by a pair of sealing rings  238 ,  240 . The sealing rings  238 ,  240  allow the components  186 ,  188  to rotate with respect to one another while a fluid tight seal is maintained therebetween. In this exemplary embodiment, the seal rings  238 ,  240  have different cross-sectional shapes, with the first seal ring  238  (nearest to the plateau  224 ) having a rectangular cross-section, while the second seal ring  240  (nearest to the proximal tip) includes a circular cross-section. 
         [0035]    Those skilled in the art will realize that fewer or more than two seal rings may be utilized. Moreover, if multiple seal rings are utilized, any of various shapes of seal rings may be utilized. In addition, if multiple seal rings are utilized, the seal rings may all have the same cross-sectional shape and size, or the seal rings may have different shapes and/or sizes. 
         [0036]    Referring back to  FIGS. 1 and 3 , the proximal component  186  also includes an integrally formed barb fitting  246  having generally the same shape and features as the barb fitting  192 , of the distal component  188 , except in the opposite direction. Accordingly, like elements of the barb fittings  192 ,  246  have been labeled commonly in the figures. Unlike the barb fitting  192  of the distal component  188 , the barb fitting  246  of the proximal component  186  is not integrally formed as a single piece with the housing  248  of the proximal component. Instead, the barb fitting  246  is a separate structure that is at least one of welded, brazed, and soldered to join the fitting with the housing  248  to ensure a fluid tight seal at the joint  250 . In exemplary form, the housing  248  includes a proximal opening that extends into a cylindrical cavity partially occupied by the barb fitting and the distal component  188 . 
         [0037]    The dimensions of the cylindrical cavity generally match those of the exterior of the barb fitting  246  in order to retain the barb fitting therein by way of a compression fit. The cavity is also partially defined by a step  254  providing a depthwise endpoint upon which a portion of the base  256  of the barb fitting  246  is seated. This step  254  also marks the proximal endpoint of the distal component  188 . In exemplary form, the proximal end of the distal component  188  abuts the base  256  of the barb fitting  246  when the vertical wall  216  abuts the distal end  260  of the proximal component  186 . However, because of the distance between the front side of the plateau  224  the vertical wall  216  is greater than the width (i.e., depth) of the circumferential end flange  220 , there is the potential for longitudinal play between the components  186 ,  188 . But this play does not substantially affect the outer shape of the housing  248  which includes a cylindrical section  262  and a tapering section  264  that decreases in diameter from distal to proximal until terminating at the exterior of the barb fitting  246 . In this manner, the swivel  180  is tapered on both sides to reduce the likelihood of snagging when moved longitudinally forward or rearward. As with the distal barb fitting  192 , the proximal barb fitting  246  includes a vertical step  204  operative to retard the proximal section  182  of the exhaust conduit from substantial proximal movement that would remove the conduit from the barb fitting  246 . Distal from the swivel section  112  is the tool attachment section  114 . 
         [0038]    Referring to  FIGS. 1 and 4 , the tool attachment section  114  includes a collar  270  and a radially extending tab  272 . This tab  272  includes a top and opposed bottom surfaces  276 ,  278  each having at least one projection  280  extending either or both surfaces. In this exemplary embodiment, each surface  276 ,  278  of the tab  272  includes a pair of perpendicularly extending, oblong projections  280 . These projections  280  help a set of robotic jaws (now shown) grasp the tab  272  and correspondingly reposition the wand  102 . 
         [0039]    In exemplary form, the collar  270  is fabricated from any suitable, biocompatible material and includes a through passage that receives the distal section  184  of the exhaust conduit  128  attached to the swivel section  112 . The through passage has a circular cross-section that is non-uniform. A vertical step  284  interposes an inner circumferential wall  286  and another inner circumferential wall  288 . The vertical step  284  is operative to decrease the diameter of the passage from the larger diameter walls  286  to the smaller diameter walls  288 . Both sets of walls  284 ,  288  have a substantially constant (but different) diameter to define cylindrical cavities that are longitudinally aligned and sequential with respect to one another. 
         [0040]    One section  184  of the exhaust conduit is located within the proximal cavity, while a boiler tube  300  is frictionally mounted to the collar  270  within the distal cavity using a friction fit. In exemplary form, the boiler tube  300  is hollow and includes a closed distal end  302  and an open proximal end  304 . This open proximal end  304  is sized to receive a barb fitting  306 . The barb fitting  306  is a separate structure that is at least one of welded, brazed, and soldered to the interior of the boiler tube  300  to ensure a fluid tight seal therebetween. 
         [0041]    Consistent with the structure of the foregoing barb fittings, this barb fitting  306  also includes a circular opening  308  that leads into a cylindrical cavity bounded by an interior surface  310  having a substantially constant diameter. The circular opening  308  is defined by a circular lip  312  that transitions into the exterior surface  314 . This exterior surface  314  tapers outward from the lip  312  to increase its diameter, terminating at a vertical step  316  to form the barb. This vertical step  316  operates to retard the distal section  184  of the exhaust conduit from substantial distal movement that would remove the conduit from the barb fitting  306 . Beyond the barb, traveling proximally, the exterior surface includes a substantially cylindrical, constant diameter section  318  that extends to reach a second vertical step  320 . This second vertical step  320  is coplanar with the open  322  of the boiler tube  300  and signals an increase in the thickness of the fitting  306  wall to approximate the internal diameter of the boiler tube  300 . 
         [0042]    The end  322  of the boiler tube  300  extends partially into the proximal cavity. This cavity is sized to receive the boiler tube  300 , the barb fitting  306 , as well as a portion of the distal section  184  of the exhaust conduit. Specifically, the diameter of the proximal cavity is greater than the outside diameter of the distal section of the exhaust conduct, which thus leaves a circumferential gap  324 . 
         [0043]    The boiler tube  300  includes a generally circular cross section and a longitudinal cylindrical profile when oriented in a linear fashion. However, the tube  300  may be deformed to take on shapes, other than a linear orientation such as a candy cane shape. In this circumstance, the tube  300  comprises an aluminum shell having a nominal wall thickness ranging between about 0.020 in. to about 0.035 in. and an outside diameter of from about 0.16 in. to about 0.20 in. This wall thickness allows the tube  300  to be deformed in an arcuate manner without causing a crack or other breach allowing communication between the exterior and interior of the shell. 
         [0044]    It should be noted that in lieu of aluminum, other materials may be used to construct the tube  300 . For example, the tube  300  may be fabricated from Series 1000 aluminum alloy or other metals and alloys including, without limitation, gold, gold alloys, stainless steel, nitinol, or other malleable metals and metallic alloys having suitable thermal conductivity. In exemplary form, the tube  300  is formable into various shapes appropriate for making the different ablation lines, but is stiff enough for tissue conformance and to maintain its shape when applied to cardiac tissue without any secondary reinforcement. Likewise, the exemplary tube  300  is capable of being bent in an arcuate manner to have a minimum radius of approximately 0.5 in. 
         [0045]    The tube  300  has a smooth outer surface over the vast majority of its length. In this exemplary embodiment, the tube  300  has an overall length of approximately 43 cm. It should be noted, however, the lengths longer than 43 cm and shorter than 43 cm may also be utilized. In order to house and encase the cryogenic fluid flowing within the tube  300 , the interior of the tube  300  is generally hollow and enclosed at the distal end  302 . In exemplary form, the distal tip of the tube  300  embodies a generally hemispherical shape. 
         [0046]    On the interior of the tube  300  is the feed conduit  128  that directs cryogenic fluid proximate the closed end  302 . In this exemplary embodiment, the feed conduit  128  includes a generally circular cross section and a longitudinal cylindrical profile when oriented in a linear fashion. However, the feed conduit  128  may be deformed to take on shapes other than a linear orientation. In this exemplary circumstance, the feed conduit  128  comprises an aluminum shell having a nominal wall thickness ranging between 0.02-0.035 inches and a nominal internal diameter ranging between 0.005-0.012 inches. It should be noted that in lieu of aluminum, other materials may be used to construct the feed conduit  128 . For example, the feed conduit  128  may be fabricated from Series 1000 aluminum alloy or other metals and alloys including, without limitation, gold, gold alloys, stainless steel, nitinol, or other malleable metals and metallic alloys having suitable thermal conductivity. 
         [0047]    The wall thickness allows the feed conduit  128  to be deformed in an arcuate manner to generally track the deformity in the tube  300 . In this exemplary embodiment, the feed conduit  128  includes a nozzle (not shown) having a cross-sectional area that achieves a flow rate of 1,000-1,600 cubic centimeters per minute at 15 psi. The nozzle is backset from the enclosed end  302  of the tube  300 . By way of example, and not limitation, the inside diameter of the feed conduit  128  generally has a length from about 10 inches to about 20 inches and a corresponding cross sectional area generally from about 0.000314 square inches to about 0.00196 square inches. It is also within the scope of the disclosure to provide multiple nozzles, some of which may be staggered along the length of the tube  300 . 
         [0048]    Though not required, the interior of the tube  300  may include an internal flexible support, such as a metal coil (not shown), to prevent kinking and to help maintain the circular cross-section of the tube during deformation. In this exemplary embodiment, the flexible support comprises a stainless steel coil. The flexible support may also serve to hold together segments of the tube  300  in the event that the tube fractures. The flexible support may be free-floating, or it may be retained in place on the interior of the tube  300  by frictional engagement with the inner wall of the shell using oversized coils. In this exemplary embodiment, the spring  332  has a pitch generally ranging between about 0.018 in. to about 0.022 in. and an outside diameter generally ranging between about 0.115 in. to about 0.125 in. 
         [0049]    In use, the exterior surface of the tube  300  has surface temperatures below −40° C. When the tube  300  is applied to the tissue to be treated, freezing of tissue coming into direct contact with the shell results. Surrounding tissue is sequentially frozen by the withdrawal of heat from the tissue as the tube  300  maintains contact with tissue over time. 
         [0050]    Surfaces of the cryogenic wand  102  that are not intended for potential contact with patient tissue may be insulated for the protection of both non-target tissue and the cryogenic probe user. To this end, a sleeve (not shown) may circumscribe portions of the wand, thus protecting adjacent tissue that may come into contact with what would otherwise be exposed portions of the wand  102 . 
         [0051]    The cryogenic probe  100  may be used in an open procedure on an arrested heart, with the shell  106  being applied to the endocardium or inner surface of the heart (through a purse-string opening), or alternatively to the epicardium or outer surface of the heart. The freezing of the cardiac tissue causes an inflammatory response (cryonecrosis) that blocks the conduction of electrical pulses. 
         [0052]    All materials used in the cryogenic probe  100  that are exposed to the cryofluid may be compatible with the cryofluid used in the device, and components intended for patient contact may be biocompatible. The device (and its packaging) may also be gamma stable, as gamma sterilization is an exemplary sterilization method. 
         [0053]    As is known to those skilled in the art, a cryogenic device operates as a result of a cryofluid undergoing expansion as the fluid moves through the nozzle of the feed conduit  128  and into the open cavity of the tube  300 . By way of example, the feed conduit  128  may deliver cryogenic fluid at a relatively high pressure, which drastically reduces its pressure after exiting the supply tube and entering the tube proximate its end  302 . Temperatures within the interior of the tube  300  can fall below −60° C., and provide for exterior surface temperatures of the shell of less than −45° C., for example, when nitrous oxide gas is used as the cryofluid. 
         [0054]    The inventors have found that it may be advantageous to utilize the exhaust cryogenic fluid to reduce the temperature of the feed cryogenic fluid. Accordingly, the first exemplary cryogenic probe  100  makes use of a countercurrent flow pattern within the coaxial section  120  (see  FIG. 2 ) so that the exhaust conduit  126  circumscribes and longitudinally extends around the feed conduit  128 . In this manner, the feed conduit leaving the tank includes cryogenic fluid a pressure ranging between 650-900 psi at a temperature of 22 C and ultimately delivers the cryogenic fluid at the nozzle at a pressure of 700 psi and a temperature of −55 C. 
         [0055]    While not shown in the figures, it is also within the scope of the invention to provide multiple feed conduits  128 . As a result, each of the multiple feed conduits  128  includes a separate passageway for cryogenic fluid to enter the tube  300 . 
         [0056]    In addition, the cryogenic probe  100  may be provided with a system for determining the surface temperature of the tube  300  and provide the user with that data. To this end, the outer surface of the tube  300  may be provided with a temperature measuring device, such as a thermocouple. Wiring on the outside of the tube  300  transmits signals generated by the thermocouple to a display associated with the cryogenic console  108  having a read-out visible to the user. By way of example, the thermocouple may be a type T calibration thermocouple which is suitable ranging between −250° C. and 350° C. 
         [0057]    Referring to  FIG. 5 , a second exemplary cryogenic probe  400  includes a wand  402  coupled to an umbilical tether  404  in order to supply cryogenic fluid from a fluid reservoir  106  to the wand. In this second exemplary embodiment, the flow of cryofluid to and from the cryogenic probe  400  is controlled from a separate, commercially available console  108  that regulates and controls the pressure of the cryofluid introduced into the cryogenic wand  402 . The console  108  is capable of pressurizing the wand  402  for active defrost and provides for appropriate discharge of expanded cryofluid exhaust. Alternatively, or in addition, hand controls (not shown) may be associated with the cryogenic probe  400  to regulate and control the pressure of the cryofluid introduced into the cryogenic wand  402 . In this second exemplary embodiment, the wand  402  includes a diversion section  410 , a swivel section  412 , and a tool attachment section  114 . Because this second exemplary probe  400  makes use of the same cryogenic fluid reservoir  106 , console  108 , and tool attachment section  114 , a detailed description of these components will not be duplicated for purposes of brevity. 
         [0058]    Referring to  FIGS. 5 and 6 , the swivel section  412  includes a swivel  414  surrounded by an insulated housing  416  fabricated from complementary plastic halves. Each half includes a generally smooth exterior surface having a middle section  418  with a substantially constant radius that transitions into semi-conical sections  420  having a frustum  422 . Each frustum  422  includes a semi-circular opening  424  that is longitudinally aligned with the opposing frustum. An interior of each housing  416  half includes two different shaped sets of semi-circular ribs  426 ,  428  that protrude from an interior housing wall  430  and toward the cryogenic feed line  128 . The first set of ribs  426 , comprising a corresponding pair on each end, one defining the frustum  422  and another being inset a predetermined distance from the frustum  422  and operate to define a semi-circular opening  434  having generally the same dimensions as the semi-circular opening  424  of the frustum  408 . As can be seen in the drawings, the radial length of the first set of ribs  426  is substantially greater than the radial length of the second set of ribs  428 . In this exemplary embodiment, the second set of ribs  428  are three in number and are oriented in between the first set of ribs  426 . The difference in radial length between the ribs  426 ,  428  at least partially defines an internal cavity occupied by a scaling sleeve  436 , swivel segments  438 , and sealing rings  440 . 
         [0059]    The sealing sleeve  436  comprises a metallic cylinder having hollow interior and opposing open ends. The exterior surface of the sleeve  436  is generally smooth and circular, as is the interior surface. In this exemplary embodiment, the hollow interior defines a cylindrical cavity having a circular cross-section of substantially identical diameter along its length. By way of example, and not limitation, the wall thickness of the sleeve is 1 millimeter. However, it should be understood that the wall thickness may depend upon the material properties of the sleeve. The other dimensions, such as the length, width (diameter), may be dictated by the dimensions of the swivel segments  438  and sealing rings  440 . However, it should be apparent to those skilled in the art that the dimensions are a matter of design choice. In this exemplary embodiment, the exterior surface of the sleeve  436  is adjacent to the second set of ribs  442  from each housing  416  half. Opposing open ends of the sleeve  436  abut complementary interior radial surfaces  442  of the first set of ribs  426  in order to wedge the sleeve between the first set of ribs. Upon assembly of the swivel  414 , as will be discussed below, the sleeve  436  does not appreciably move radially outward or longitudinally while seated within the housing  416  halves. 
         [0060]    The complementary interior radial surfaces  442  of the first set of ribs  426  also operate to retain the swivel segments  438  and sealing rings  440  within the sleeve  436  when the housing  416  halves are assembled. Specifically, each swivel segment  438  includes a base  444  having a through hole  446  that is generally centered within the base. This through hole  446  extends through the base  444  and through an adjoining conduit  448  until terminating at the end  450  of the conduit. In this exemplary embodiment, the through hole  446  is bounded by a continuous interior surface having a generally constant diameter from the base  444  to proximate the end  449  of the conduit  448  where the interior surface tapers outward to gradually increase the diameter until reaching the end of the conduit. The simplicity of the interior topography contrasts the complexity of the exterior topography. 
         [0061]    The exterior topography of each swivel segment  438  includes the substantially flat, circular base  444  discussed above. This base  444  extends radially outward from the through hole  446  to create a circumferential flange  450 . A second circumferential flange  452  is longitudinally spaced apart from the first flange  450  and cooperates with the first flange to define a trough into which, the scaling ring  440  is seated. By way of example, and not limitation, the trough has a generally block U-shaped cross-section resulting from opposing walls of the flanges  450 ,  452  intersecting a circular, inset  460  wall. The depth and the width of the trough may be established based upon the desired dimensions of the sealing ring  440  so that the sealing ring fits within the trough in a compression manner. While not shown, it should be understood that lubricant may be applied to the sealing ring  440  before or after being seated within the trough to facilitate sealing and rotational motion of the swivel segment  438  with respect to the sealing ring. Both flanges  450 ,  452  include generally smooth, circular outer walls  462  that are rounded over to transition into corresponding flat interior walls that delineate the trough, with the second flange having another flat wall that intersects a circular outer wall  466  of the conduit that is inset (includes a smaller outer diameter) with respect to the base  444 . Proximate the end of the conduit  448  is a frustoconical flange  470  having a vertical wall  472  perpendicular to a conical wall  474  that terminates at the end. Reference will not be had to assembly of the aforementioned components. 
         [0062]    Assembly includes seating the sealing rings  440  within the troughs of the swivel segments  438  so that each sealing ring is received within a different trough. Thereafter, the swivel segments  438  are oriented to so the flat walls at the bottom of each base  444  generally abut one another and the respective through holes  446  are longitudinally aligned with one another. In this orientation, the ends  449  of the conduits  448  of the swivel segments  438  point away (opposite) from one another. The bases  444  are likewise positioned to occupy the hollow interior of the sleeve  436 . In exemplary form, the longitudinal length of the sleeve  436  is generally twice the longitudinal length of each base  444 . Accordingly, when the bases  444  are oriented to abut one another and are located within the interior of the sleeve  436 , the open ends of the sleeve are generally flush with the flat walls  464  of the second flange  452  of each base  444 . This sub-assembled structure (sleeve and two swivel segments) is inserted between two housing  416  halves so that the interior of the housing halves is occupied by the sleeve and swivel segment bases  444 . 
         [0063]    In particular, the housing  416  halves are aligned so that the first set of ribs  426  operatively define corresponding cylindrical openings that are occupied by a conduit  448  of each swivel segment  438 . At the same time, the housing  416  halves are aligned so that the second set of ribs  428  operatively define corresponding cylindrical openings that are occupied by the sleeve  436 . As discussed above, the exterior surface of the sleeve  436  is adjacent to the innermost surface of the second set of ribs  428  and opposing open ends of the sleeve  436  abut complementary interior radial surfaces  442  of the first set of ribs  426  in order to wedge the sleeve between the first set of ribs. In this manner, the sleeve  436  does not appreciably move radially outward or longitudinally while seated within the housing  416  halves. Because of the longitudinal length of the conduits  448 , the conduits extend through and beyond circular openings formed by the cooperation of the semicircular openings  424  of the frustums  422 . As a result of the foregoing assembly, the swivel segments  438  are able to axially rotate with respect to one another, while maintaining a seal between the swivel segments. More specifically, one conduit  448  is mounted to the distal section  184  of the exhaust conduit, while the other conduit  448  is mounted to the proximal section  182  of the exhaust conduit. In this manner, the distal and proximal sections  182 ,  184  are able to rotate independent of one another. 
         [0064]    The foregoing bases  444  and conduits  448  have been shown and described as being an integral structure. However, it should be realized that each swivel segment  438  may be fabricated from multiple pieces that are permanently mounted to one another or are removably mounted to one another. 
         [0065]    Likewise, while the foregoing swivel section  412  provided a swivel for the exhaust conduit sections  182 ,  184 , the same swivel structure may be duplicated and miniaturized to provide a swivel for the cryogenic feed conduit  128 . 
         [0066]    Referring to  FIGS. 5 and 7 , the diversion section  410  is upstream, with respect to the feed cryogenic fluid flow, from the swivel section  412 . Similar to the diversion section  110  discussed in the first exemplary embodiment, this diversion section  410  operates to delineate between the coaxial section  420  and the parallel section  422  by using a diverter  424  within an insulating housing  426  comprised of complementary halves. It is to be understood, however, that the housing may be a single piece, such as an injection molded jacket. The housing  426  includes two openings  416 ,  418  oriented at opposite ends of the housing, with the larger of the two openings  418  located at a proximal end of the housing and allowing throughput of both the separate exhaust conduit  126 ′ and separate feed conduit  128 ′ from the diverter  424 , whereas the smaller of the two openings  416  at the distal end of the housing allows throughput of the coaxial conduits  126 ,  128  to the diverter. 
         [0067]    The diverter  424  includes a cryogenic feed barb fitting  432  that includes a smooth cylindrical cavity sized to receive the cryogenic feed conduit  128  and create a friction fit therewith. In this exemplary embodiment, the proximal end  434  of the barb fitting  432  marks the origination point of the cryogenic feed conduit  128 , while the line  128 ′ in communication by the cryofluid reservoir  106  (see  FIG. 5 ) extends distally past the proximal end to circumscribe the barb fitting  432 . 
         [0068]    The diverter  424  also includes a T-fitting  444  that operates to take the two coaxial fluid conduits (exhaust and cryogenic feed) and break these conduits up into two non-coaxial fluid conduits. The T-fitting  444  includes a first sub-fitting  446  that is coupled to the distal exhaust section  126 . This sub-fitting  446  includes a longitudinal channel sufficient to accommodate the cryogenic fluid feed conduit  128  and provide a transition between the exhaust conduit  126  and the interior of the sub-fitting in order to carry the exhausted cryofluid further into the interior of the T-fitting  444 . Within the interior of the T-fitting is a circumferential flange  448  having an orifice that is sized to accommodate only the diameter of the cryogenic feed conduit  128 . More specifically, the exterior of the cryogenic feed conduit  128  and the portion of the flange  448  defining the orifice form a seal that prohibits passage of exhausted cryofluid from coaxially flowing over the top of the cryogenic feed conduit as the cryogenic feed conduit continues proximally within the diverter  424 . Ultimately, the cryogenic feed conduit  128  terminates proximate the proximal end of barb fitting  432 , which mounts to the cryogenic feed conduit  128 ′ that supplies cryogenic fluid from the supply reservoir  106 . 
         [0069]    Proximate the circumferential flange  448 , the T-fitting  444  includes a perpendicular offshoot  452  in fluid communication with and circumscribed by a branch conduit  454  having its own barb fitting  456  at the proximal end thereof. This barb fitting  456  is similar to the barb fittings discussed above in terms of having inclined faces to provide a conical profile that allows the separate exhaust conduit  126 ′ to more easily circumscribe the fitting  456 . At the same time, the barb fitting  456  includes vertical walls to retard proximal movement of the separate exhaust conduit  126 ′ after the separate exhaust conduit is installed around the fitting  456 . In exemplary form, the branch conduit  454  is at least one of welded, brazed, and soldered to the perpendicular offshoot  452  to ensure a fluid tight seal therebetween. 
         [0070]    The interior of the housing  416  includes a series of ribs  460 ,  462 ,  464  that protrude from an interior surface and operate to align the diverter  424  and conduits  126 ,  128 ,  126 ′,  128 ′. Distal from the diverter  424  is a strain adapter  470  that circumscribes the coaxial conduits  126 ,  128  and provides transition and support between the housing  426  and the coaxial conduits. The strain adapter  470  includes a polymeric cover  472  that tapers from distal to proximal and includes a series of circumferential ribs  474  that partially define a longitudinal channel occupied predominantly by the coaxial conduits  126 ,  128 . 
         [0071]    Referring to  FIGS. 8-10 , a third exemplary cryogenic probe  500  includes a wand  502  coupled to an umbilical tether  504  in order to supply cryogenic fluid from a fluid reservoir  106  to the wand. In this third exemplary embodiment, the flow of cryofluid to and from the cryogenic probe  500  is controlled from a separate, commercially available console  108  that regulates and controls the pressure of the cryofluid introduced into the cryogenic wand  502 . The console  108  is capable of pressurizing the wand  502  for active defrost and provides for appropriate discharge of expanded cryofluid exhaust. Alternatively, or in addition, hand controls (not shown) may be associated with the cryogenic probe  500  to regulate and control the pressure of the cryofluid introduced into the cryogenic wand  502 . In this third exemplary embodiment, the wand  502  includes an integrated swivel and diversion section  510  and a tool attachment section  114 . Because this third exemplary probe  500  makes use of the same cryogenic fluid reservoir  106 , console  108 , and tool attachment section  114 , a detailed description of these components will not be duplicated for purposes of brevity. 
         [0072]    Referencing  FIGS. 9 and 10 , an exemplary integrated swivel and diversion section  510  includes a swivel diverter  512 , which may be used in place of the diverters and swivels of the foregoing exemplary embodiments. The swivel diverter  512  includes a swivel  514  so that the proximal and distal sections  182 ,  184  of the exhaust conduit can rotate with respect to one another. In this exemplary embodiment, the swivel  514  includes a proximal component  516  and a distal component  518  that are rotationally repositionable with respect to one another. Each component  516 ,  518  includes a longitudinal passage  520  defined by a series of interior surfaces of the components that accommodates throughput of the feed conduit  128 , but is also large enough to accommodate a separate stream of exhaust cryogenic fluid. More specifically, the interior circumferential surface of the feed conduit  128  provides a sealed delivery mechanism for the cryogenic fluid delivered from the cryogenic fluid tank. At the same time, the interior surfaces of the components  516 ,  518  cooperate with the exterior surface of the feed conduit  128  to define a sealed delivery mechanism for the exhausted cryogenic fluid. 
         [0073]    The distal component  518  includes a barb fitting  522  having a circular opening that leads into a cylindrical cavity bounded by an interior surface having a substantially constant diameter. The circular opening is defined by a circular lip that transitions into the exterior surface  530  of the barb fitting  522 . Beyond the barb, traveling proximally, the exterior surface is substantially cylindrical and is inset, within the primary distal component housing  531 . This exterior of the distal component housing includes a first vertical wall  532  that intersects a first circumferential wall  534 , which itself intersects a second vertical wall  536 . This second vertical wall  536  intersects a second circumferential wall  538 , which defines the maximum diameter of the distal component  518 . Immediately proximal to this second circumferential wall  538  is a third vertical wall  540  that marks the transition where the exterior surfaces of the distal component  518  are contacted by and/or circumscribed by the proximal component  516 . The third vertical wall  540  intersects a third circumferential wall  542 , which itself intersects a fourth vertical wall  544 . This fourth vertical wall  544  cooperates with the third circumferential wall  542  and the third vertical wall  540  to define a first circumferential groove  546  that extends around the exterior of the distal component  518 . The fourth vertical wall  544  transitions into a fourth circumferential wall  548  that intersects a fifth vertical wall  550 . The fifth vertical wall  550  intersects a fifth circumferential wall  552  that extends to the proximal tip  554  of the distal component  518 . The proximal tip  554  includes a circular opening  556  that allows egress into the cylindrical longitudinal channel  520  that extends through the center of the distal component  518 . This longitudinal channel  520  is occupied by a portion of the feed conduit  128 , while the remaining area of the channel is available to act as the exhaust conduit  184 . 
         [0074]    As mentioned previously, a portion of the distal component  518  is circumscribed by a portion of the proximal component  516  and includes a first and second seal  570 ,  572  interposing the components to inhibit cryogenic exhaust from leaking between the components. Specifically, the first seal  570  is circular and has a rectangular cross-section and is spaced apart from the second seal  272 , which is also circular, but has a circular cross-section. In this exemplary embodiment, the proximal and distal components  516 ,  518  cooperate to define a pair of circumferential cavities  574 ,  576 , but only one of which is used to house the seals  570 ,  572 . However, those skilled in the art will realize that one or more seals may be located in the first cavity  574 . At the same time, those skilled in the art will realize that the second cavity  576  may have none, one, or more than one seal. 
         [0075]    In order to create the cavities  574 ,  576 , the proximal component  516  is hollow and includes a distal end  580  having a circumferential flange  582  that extends axially inward and is partially received within the first circumferential groove  546 . A vertical, proximal wall  584  of the flange  582  contacts the fourth vertical wall  544  of the distal component  518  in order to retard the proximal component from proximally disengaging the distal component  518 . Adjacent the proximal wall  584  is a conical wall  586  that intersects another vertical wall  588 . The walls  584 ,  586 ,  588  of the proximal component  516  and the fourth circumferential wall  548  of the distal component generally define the first circumferential cavity  574 . Adjacent to the vertical wall  588  is a cylindrical wall  590  that extends proximally until reaching a step  592 , which intersects a second, smaller diameter cylindrical wall  594 . The first cylindrical wall  588  and the step  592  of the proximal component  516  and the fifth circumferential wall  552  and fifth vertical wall  550  of the distal component  518  collectively generally define the second circumferential cavity  576  that houses the seals  570 ,  572 . Those skilled in the art will realize that fewer or more than two seals  570 ,  572  may be utilized. Moreover, if multiple seals  570 ,  572  are utilized, any of various shapes of seals may be utilized. In addition, if multiple seals are utilized, the seals may all have the same cross-sectional shape and size, or the seals may have different shapes and/or sizes. 
         [0076]    The swivel diverter  512  also includes a diverter  600  that is mounted to the proximal component  516  of the swivel  514 . Specifically, the proximal end of the proximal component  516  is mounted to an adapter  602  of the diverter  600 . In this exemplary embodiment, the proximal component  516  includes a proximal opening extending into its interior that is adapted to receive the adapter  602 . Specifically, the interior of the proximal component  516  includes a threaded internal wall  604  that interfaces with threads  606  of the adapter  602  to secure the adapter  602  (overall, the diverter  600 ) to the proximal component. In order to ensure a fluid tight seal between the adapter  602  and the proximal component, a seal  608  interposes the proximal component and the housing  610  of the diverter  600 . 
         [0077]    The diverter  600  comprises a cryogenic feed barb fitting  632  that includes a smooth cylindrical cavity sized to receive the cryogenic feed conduit  128  and create a friction fit therewith. In this exemplary embodiment, the proximal end  634  of the barb fitting  632  marks the origination point of the cryogenic feed conduit  128 , while the feed line  128 ′ in communication by the cryogenic fluid tank extends distally past the proximal end to circumscribe the barb fitting  632 . The barb fitting  632  includes three barbs characterized by an inclined face (from proximal to distal) and a vertical wall intersecting the inclined face. The inclined faces provide a conical profile that allows the feed line to more easily circumscribe the fitting  632  and be repositioned distally, while the vertical walls retard proximal movement of the feed line after the feed line is installed around the fitting. The barb fitting  632  is an integral part of a diverter housing  610  having a longitudinal cavity through which the feed conduit  128  extends. The profile of the longitudinal cavity  642  extending through the diverter housing  610  changes from proximal to distal, with the distal portion being sized only to accommodate the cryogenic feed conduit  128 , but moving distally, the profile increases to provide a portion of the exhaust conduit. 
         [0078]    The diverter housing  610  includes a T-fitting  644  that operates to change the profile of the longitudinal cavity  642 . The base section  646  of the T-fitting  644 , which extends perpendicularly with respect an adapter section  648  and is in fluid communication therewith, is circumscribed by a branch conduit  650  having its own barb fitting  652  at the proximal end thereof. This barb fitting  652  is similar to the barb fitting  632  discussed above in terms of having inclined faces to provide a conical profile that allows the separate exhaust conduit  126 ′ to more easily circumscribe the fitting  652  and vertical walls to retard proximal movement of the separate exhaust conduit after the separate exhaust conduit is installed around the fitting  652 . In exemplary form, the branch conduit  650  is at least one of welded, brazed, and, soldered, to the base section  646  to ensure a fluid tight seal therebetween. 
         [0079]    In order to divert the exhaust cryogenic fluid through the branch conduit  650 , the adapter section  648  is sealed at its proximal end  654  and is large enough to provide a circumferential gap between the interior of the branch conduit and the exterior of the feed conduit  128 . This circumferential gap provides a pathway for exhaust cryogenic fluid passing from the exhaust conduit  126  to reach the base section  646 , flow into the branch conduit  650 , and ultimately flow into the separate exhaust conduit  126 ′. 
         [0080]    The swivel diverter  512  is seated within a housing  660  comprised of complementary halves. It is to be understood, however, that the housing may be a single piece, such as an injection molded jacket. The housing  660  includes two openings  662 ,  664  oriented at opposite ends of the housing, with the larger of the two openings  662  located at a proximal end of the housing and allowing throughput of both the separate exhaust conduit  126 ′ and separate feed conduit  128 ′, whereas the smaller of the two openings  664  at the distal end of the housing allows throughput of the coaxial conduits  126 ,  128 . The interior of the housing  660  includes a series of ribs  666 ,  668  that protrude from an interior surface and operate to align the diverter  124  and conduits  126 ,  128 ,  126 ′,  128 ′. 
         [0081]    Following from the above description and disclosure summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present disclosure, the disclosure contained herein is not limited to this precise embodiment and that changes may be made to such embodiments without departing from the scope of the invention as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it is not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the interpretation of any claim element unless such limitation or element is explicitly stated. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present disclosure may exist even though they may not have been explicitly discussed herein.