Patent Abstract:
A surgical apparatus for cutting a tissue mass comprising an elongated housing having a distal portion, a rotatable shaft positioned in the elongated housing, and a plurality of flexible electrocautery cutting blades extending from the housing, wherein the plurality of cutting blades are radially expandable from a first position defining a first diameter to a second larger diameter and the blades are rotatable and transmit electrical energy to cut the tissue mass.

Full Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION  
       [0001]    This patent application is based on and entitled, under 35 USC 120, to the benefit of the filing date of U.S. provisional application No. 60/053,664 filed Jul. 24 1997 by James F. McGuckin, Jr. and entitled “Minimal Access Breast Surgery Apparatus and Method”. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    This invention relates to surgical apparatus and methods for obtaining a subcutaneous target mass having varied shape and dimension.  
         BACKGROUND OF THE INVENTION AND DESCRIPTION OF THE PRIOR ART  
         [0003]    Modern medical diagnostics increasingly rely on complex imaging technologies to identify abnormal conditions and/or masses within the human body. Such technologies as magnetic resonance imaging (MRI), ultrasonics, computerized axial tomography (CAT scan), and mammogram x-rays, aid medical personnel in the initial identification of areas within the body exhibiting potentially dangerous, abnormal biological activity. The beneficial aspect of these technologies is their ability to image biological structures interior to the human body, providing a non-invasive tool useful in facilitating preliminary diagnosis and treatment of detected anomalies.  
           [0004]    Detected subcutaneous biological growths, masses, etc. once identified generally require complete surgical excision or at the very least an open biopsy procedure.  
           [0005]    Small masses such as calcifications encountered in breast tissue are generally removed in their entirety. The process of excising the mass is an invasive process, performed either during exploratory surgery or utilizing specifically designed surgical apparatus. The retrieved specimen is subsequently pathologically analyzed to determine its biological properties, i.e. benign or malignant.  
           [0006]    Several types of apparatus are known for use in removing portions of subcutaneous masses in breast tissue targeted by these imaging techniques. However, these apparatus generally either obtain only small tissue specimens from the main mass or cause significant surface scarring due to the size of the incision necessary to remove the mass with a safe resection margin.  
           [0007]    One type of specimen retrieval is performed with needle aspiration devices. These devices have a needle with an end hole. The needle is advanced to a desired location where a sample specimen is obtained via suction. Size and quality of specimens obtained by these devices are often poor, requiring multiple sampling of each desired target mass. Moreover, tissue encountered along the path to the desired location is unavoidably removed. A hollow channel is created upon withdrawal of the device from the patient, thereby allowing “seeding” of the hollow channel removal tract with abnormal cells. Some needle systems utilize an enlarged needle end hole, creating a boring probe which obtains a greater portion of tissue. This lessens the likelihood that the specimen will be too small but increases the amount of surface scarring due to the larger size incision required.  
           [0008]    The percutaneous incisions needed when multiple needle channels or large needle bore channels are used often result in significant scarring, dimpling and disfigurement of surface tissue.  
           [0009]    Needle side cutting devices have a blade extending around the circumference of a hollow needle shaft. The shaft and blade are axially rotated around the skin entry site, allowing a larger overall specimen to be excised. Target tissue is sliced and a non-contiguous specimen is obtained due to the spiral blade path. While these needle side cutting devices facilitate capture of larger sample specimens, they require resection of a relatively large core of tissue between the incision and the specimen desired to be resected. Additionally, needle side cut devices result in irregularly shaped specimens and subcutaneous cavities having irregular and/or bleeding margins.  
           [0010]    Hence, the known devices are particularly ill suited in retrieving tissue masses from the female breast, due to the interest in preserving cosmetic integrity of the surface tissue as well as the inability of the known devices to remove most masses/calcifications during a single application.  
         SUMMARY OF THE INVENTION  
         [0011]    This invention provides surgical apparatus and methods where size and shape of subcutaneous tissue identified for excision is minimally dependent on dimensions of the percutaneous incision. The apparatus and methods have specific utility in breast surgery.  
           [0012]    In one of its aspects this invention provides apparatus for excision of the subcutaneous target tissue mass through a cutaneous incision smaller than maximum transverse dimension of the tissue mass excised where the apparatus includes an axially elongated member including cutaneous tissue piercing means at one end and means connected to the elongated member and being radially expandable relative thereto for cutting a circumferential swath of radius greater than maximum transverse dimension of the elongated member and greater than maximum transverse cross-sectional dimension of the target tissue mass in order to separate the target tissue mass from surrounding tissue for excision thereof through the incision. The apparatus may further include an expandable aseptic shield concentric with the elongated member and axially slidably advanceable over the cutting means when in the radially expanded configuration, to collectibly bag the target tissue mass detached from the patient by the cut circumferential swath, for aseptic removal in an axial direction together with the elongated member through the incision resulting from entry of the cutaneous tissue piercing means.  
           [0013]    The apparatus may yet further include a sheath which is axially slidably concentric with the elongated member and connected to first ends of the cutting means for expanding the cutting means from generally linear and axial orientation to a curved basket-like orientation by axial movement relative to the elongated member.  
           [0014]    In yet another of its aspects the invention provides apparatus for excision of a sub-cutaneous target tissue mass through a cutaneous incision smaller than maximum transverse dimension of the tissue mass excised where the apparatus includes an axially elongated member through which cutaneous tissue piercing means may be extended to emerge at one end thereof. The apparatus further includes means insertable through the elongated member which is radially expandable relative to the elongated member for cutting a conical swath having base radius greater than maximum transverse dimension of the elongated member and greater than maximum transverse cross-sectional dimension of the target tissue mass, for separating the target tissue mass from surrounding tissue for removal thereof through the incision. In this embodiment of the invention the apparatus further preferably includes expandable aseptic shield means insertable through the elongated member and advanceable over the path of the cutting means to radially expand and collectibly bag the tissue mass detached from a patient by the conical swath cutting for aseptic removal in an axial direction through the elongated member and the incision resulting from entry of the cutaneous tissue piercing means.  
           [0015]    In one of its aspects this invention preferably provides such apparatus having a piercing segment for penetrating a percutaneous entrance incision. The forward edge of the piercing segment preferably separates breast tissue in the path of the target tissue to be excised. The piercing segment preferably passes through the specimen to be excised, delivering an associated preferably circular array of preferably highly flexible cutting blades to the interior identified subcutaneous breast growth.  
           [0016]    The circular array of preferably flexible cutting blades is preferably radially expanded by action of an attached actuating shaft. The blades radially expand to preferably cut by electro-cauterizing the breast tissue as they rotate around a defined periphery. The blades preferably outwardly expand to envelope the target tissue specimen and axially rotate to separate the target tissue growth from surrounding breast tissue. The target tissue growth is excised from surrounding breast tissue outisde the periphery of the circular blade path and is preferably secured by a snaring membrane placed riding over the circular array of flexible cutting blades.  
           [0017]    The membrane is preferably secured over the blade array through an integral drawstring assembly contracting the mouth of the snaring membrane. The membrane-encased blade array is preferably drawn into a recovery sheath and compressed for aseptic removal from the excision site.  
           [0018]    In a method aspect this invention removes subcutaneous breast growths. A percutaneous surface incision is prepared for reception of surgical apparatus. Through use of suitable medical imaging technologies, the cutting apparatus device is guided to the area of the target subcutaneous breast growth while preferably maintaining a fixed subcutaneous reference point. A circular array of blades is then preferably radially expanded, preferably forming a cutting basket having dimensions larger than the target subcutaneous breast growth. Radial expansion and rotation of the electro-cauterizing blades separates the targeted growth from surrounding tissue. A snaring membrane advances over the blade array and is secured by an integral drawstring assembly. A recovery sheath compresses the membrane, encasing the target growth as it is withdrawn from the subcutaneous breast cavity. As a result, a growth which is large relative to the entrance incision is excised. In another of its method aspects this invention provides a procedure for excision of a sub-cutaneous target tissue mass through a cutaneous incision which is smaller than maximum transverse dimension of the target tissue mass to be excised where the procedure includes an advancing tissue piercing means towards a patient to create an incision in the patient&#39;s skin, slidably advancing cutting means through the incision and into sub-cutaneous tissue until in position to radially expand and cut a circumferential swath around the target tissue mass larger than the incision, cutting a circumferential swatch around the target tissue mass thereby separating the target mass from the surrounding tissue, slidably advancing flexible aseptic containment means over the separated target tissue mass to a position of closure about the target tissue mass and withdrawing the flexible aseptic containment means, with the target tissue mass aseptically contained therewithin, through the incision. The method may further include collapsing the cutting means after cutting the swath.  
           [0019]    In yet another of its method aspects, this invention provides a procedure for excision of sub-cutaneous target tissue mass through a cutaneous incision smaller than maximum transverse dimension of the target tissue mass to be excised where the procedure includes advancing tissue piercing means towards the patient to create an incision in the patient&#39;s skin, slidably advancing cutting means through the incision and into sub-cutaneous tissue until in position to gradually radially expand and cut a conical swath about the target tissue mass larger than the incision thereby separating the target tissue mass from the surrounding tissue, slidably advancing flexible aseptic containment means over the separated target tissue mass to a position of closure around the target tissue mass and withdrawing the flexible aseptic containment means with the target tissue mass aseptically contained therewithin through the incision. The invention in this aspect preferably further includes radially inwardly collapsing the cutting means, which is preferably wire, after cutting the conical swath and may yet further include radially inwardly cutting tissue along the base of said cone by a passage of the cutting wire therethrough and thereafter closing flexible aseptic containment means over about the periphery of the cone and the target tissue mass contained therewithin. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]    [0020]FIG. 1 is a side view one embodiment of apparatus manifesting aspects of the invention with the cutting blades in radially expanded condition.  
         [0021]    [0021]FIG. 2 is a side view of the surgical apparatus illustrated in FIG. 1 of the cutting blades in their non-expanded condition.  
         [0022]    [0022]FIG. 3 is a front view of a modified version of the apparatus illustrated in FIGS. 1 and 2 with the cutting blades in a non-expanded condition as illustrated in FIG. 2.  
         [0023]    [0023]FIG. 4 is a front view of a modified version of the apparatus illustrated in FIGS. 1 through 3 with the cutting blades in their radially expanded condition as illustrated generally in FIG. 1.  
         [0024]    [0024]FIG. 5 is a broken schematic partially sectioned view of female breast tissue with the apparatus illustrated in FIGS. 1 through 4 in position within the breast in the process of removing a target tissue mass from the breast with the target tissue mass encased within an aseptic shield portion of the apparatus.  
         [0025]    [0025]FIG. 6 is a side view of a portion of apparatus according one preferred embodiment of the invention shown in the course of practicing a preferred method aspect of the invention.  
         [0026]    [0026]FIG. 7 is a side view of a part of the apparatus illustrated in FIG. 6 showing additional parts of one preferred apparatus embodiment of the invention in the course of practicing the inventive method.  
         [0027]    [0027]FIG. 8 is a side view of the apparatus illustrated in FIG. 7 showing the support struts deployed.  
         [0028]    [0028]FIG. 9 is a side view of the preferred embodiment of the apparatus showing the struts deploying about a percutaneous growth.  
         [0029]    [0029]FIG. 10 is a side view of the preferred embodiment of the apparatus showing advancement of the cutting wire along a strut margin.  
         [0030]    [0030]FIG. 11 is a side view of the apparatus shown in FIG. 10 with the cutting wire fully deployed.  
         [0031]    [0031]FIG. 12 is a side view of the preferred embodiment of the apparatus depicting a new cutting wire retraction.  
         [0032]    [0032]FIG. 13 is a side view of the preferred embodiment of the apparatus showing advancement of the bagging structure.  
         [0033]    [0033]FIG. 14 is a side view of the preferred embodiment with tissue containment bagging completed.  
         [0034]    [0034]FIG. 15 is a side view of the preferred embodiment of the apparatus showing the containment sheath deploying.  
         [0035]    [0035]FIG. 16 is a side view of the preferred embodiment of the apparatus showing the containment sheath normally deployed.  
         [0036]    [0036]FIG. 17 is an isometric view of the apparatus shown in FIG. 16.  
         [0037]    [0037]FIG. 18 is a broken view of the tissue containment bag showning the drawstring tissue.  
         [0038]    [0038]FIG. 19 is a side view similar to FIG. 16 but showing the containment sheath fully deployed.  
         [0039]    [0039]FIG. 20 is a side view similar to FIG. 19 but showing the containment sheath being withdrawn.  
         [0040]    [0040]FIG. 21 is a side view similar to FIG. 19 showing optional use of a medicament bag and a radiological marker  
         [0041]    [0041]FIG. 22 is a side view similar to FIG. 19 showing optional use of liquid medication supported in part by the containment sheath.  
         [0042]    [0042]FIG. 23 is an elevation of a support member.  
         [0043]    [0043]FIG. 24 depicts the female breast and illustrated the incision resulting from practice of the method.  
         [0044]    [0044]FIG. 25 is partial end elevation taken looking from the right in FIG. 8.  
         [0045]    [0045]FIG. 26 is partial end elevation taken looking from the right in FIG. 10.  
         [0046]    [0046]FIG. 27 is partial end elevation taken looking from the right in FIG. 16.  
         [0047]    [0047]FIG. 28 is a side elevation of a second preferred embodiment of apparatus embodying the invention with hook and rod structure facilitating simultaneous performance of the cutting and bagging steps.  
         [0048]    [0048]FIG. 29 is a partially sectioned side elevation of the embodiment of apparatus illustrated in FIG. 28 prior to deployment of the hook and rod structure facilitating simultaneous performance of the cutting and bagging steps.  
         [0049]    [0049]FIG. 30 is a partially sectioned side elevation of the embodiment of apparatus illustrated in FIG. 28 showing deployment of the hook and rod structure facilitating simultaneous performance of the cutting and bagging steps. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0050]    This invention provides surgical apparatus and methods for excision of percutaneous breast tissue. The apparatus has the capability to pass through an incision substantially smaller than the maximum percutaneous target specimen dimension occupying an excision site.  
         [0051]    In one embodiment the surgical apparatus preferably cuts the target tissue with an electro-cauterizing, circular array of flexible cutting blades, preferably collecting the specimen within the periphery of an expandable blade path; thus the complete growth is preferably obtained in a single procedure. The tissue is preferably returned as a complete specimen or, alternatively, in segments within a snaring membrane. A recovery sheath is preferably positioned to further encase and compress the blade array upon contraction.  
         [0052]    Referring to FIG. 1, the illustrated embodiment of surgical apparatus  10  includes an inner rotatable shaft  20 , a tubular recovery sheath  25 , a snaring membrane  30 , a circular array of radially flexible and expandable cutting blades generally designated  50 , a membrane drawstring  80 , a membrane mouth section  27  of recovery sheath  25 , a power source  15  and a tissue piercing member  65 .  
         [0053]    Membrane  30  preferably has an inner surface  32  coaxially parallel with shaft  20 , and an outer surface  34 . Inner surface  32  of membrane  30  preferably slidably facingly contacts the outside surface  22  of shaft  20 . Membrane  30  is adjustably positioned in either the distal or proximate direction through the proximate end of shaft  20 .  
         [0054]    Tubular recovery sheath  25  preferably includes a distal pleated mouth section  27 , an outer surface  45 , and an inner surface  60  facingly coaxially contacting membrane  30 . Inner surface  60  slidably engages outer surface  34  of membrane  30 . Shaft  20  defines a rotational axis  12 .  
         [0055]    Shaft  20  rotates as denoted by arrow  12 . Rotatable shaft  20  of surgical apparatus  10  is preferably rotated manually, through mechanical hand control. However, shaft  20  may be operably linked with an electrical motor, not shown, which may be driven by power source  15 .  
         [0056]    Circular cutting blade  50  includes individual flexible blades  55  which are preferably anchored between piercing member  65  and proximate end of shaft  20 . Blades  55  are preferably electro-cauterizing, heated by electrical power source  15 .  
         [0057]    The materials utilized to construct surgical apparatus  10  are preferably radiopaque to be visible using modern medical imaging systems.  
         [0058]    Referring to FIG. 2, surgical apparatus  10  is shown with individual flexible blades  55  in their non-expandable, tissue insertion orientation. In this insertion orientation the blades are parallel with and of slightly smaller diameter than tubular recovery sheath  25 . Tubular recovery sheath  25  includes a snaring membrane  30  having a mouth section  27  and a drawstring  80 , for drawing membrane  30  closed once it has been opened. Drawstring  80  is positioned along the distal margin of mouth section  27 .  
         [0059]    Mouth section  27  of membrane  30  expands outwardly in response to pulling of a polyvinyl tab or ripcord upon reaching the excision site. The polyvinyl tab or ripcord is preferably at the end of shaft  20  to the right, which is not shown in the drawing. The polyvinyl tab or ripcord is not visible in the drawing.  
         [0060]    Recovery sheath  25  is preferably advanced over circular array of cutting blades  50  and preferably secured in place around the cutting blades and the excised specimen by pulling the drawstring towards the proximate end of shaft  20 .  
         [0061]    Referring now to FIG. 3, piercing segment  65  is formed to separate subcutaneous tissue in the path between the surface incision and the growth.  
         [0062]    [0062]FIG. 3 and FIG. 4 show a modification of the embodiment of surgical apparatus  10  illustrated in FIGS. 1 and 2. In the modification illustrated in FIGS. 3 and 4, shaft  20  includes an interior channel  21  extending forwardly through the center of the cutting blade circular array  50  and connecting with piercing membrane  65 . A shaft stem section which is not shown connects to a dye port  70  in piercing member  65  for optional delivery of marking fluid to subcutaneous areas. Dye port  70  enables operators of apparatus  10  to deliver marking substances to the subcutaneous excision site. Alternatively, a titanium clip can be ejected from a clip fastening surface  75  for marking excision sites for future medical imaging analysis.  
         [0063]    As shown in FIG. 4, the circular array  50  of cutting blades  55  expands radially upon relative moment of shaft  20  in the direction of piercing member  65 , defining a cutting orientation. Flexible cutting blades  55  are preferably electro-cauterizing, cutting as they outwardly expand and as they rotate after radially outward expansion. Upon rotation of flexible cutting blades  55  in the direction indicated by arrow A in FIG. 4, the target tissue growth is separated from the surrounding subcutaneous breast tissue and remains within the periphery of the circular blade path.  
         [0064]    As variations, the circular array of flexible cutting blades  50  may employ radially expandable ultrasonic cutting means, referred to as “harmonic scalpels”, or laser cutting means.  
         [0065]    The method of excising subcutaneous breast target tissue growths is shown in FIG. 5. In FIG. 5 the edges of a surgical site where a growth has been removed is indicated as  100 ; removal of the growth has created subcutaneous cavity  105 . As shown, subcutaneous cavity  105  is separated from a surface incision  126  by an excision distance  95 .  
         [0066]    In preparation for removing the subcutaneous breast tissue growth, percutaneous tissue is cut to produce an incision  126 . A piercing member  65  of surgical apparatus  10  is placed at incision  126 . An excision path is created by forcing piercing member  65  through the subcutaneous breast tissue between the percutaneous incision  126  and the identified target tissue growth. The target tissue growth is the desired excision site which is visualized via a medical imaging system such as ultrasound or mammography. The tip of surgical apparatus  10  is advanced until the piercing segment passes through the growth to be excised.  
         [0067]    Once apparatus  10  is properly positioned relative to the target tissue mass as indicated by the medical imaging system, the proximate end of shaft  20  is urged towards piercing member  65 . Flexible cutting blades  55  radially expand to define subcutaneous margin  100 . The array of flexible cutting blades  50  is then rotated about the shaft axis as indicated by arrow  12 , separating the target tissue growth along margin  100 .  
         [0068]    Membrane  30  is then advanced over the circular array of cutting blades  50  and secured by pulling integral drawstring  80  to the right in FIG. 5 towards the end of shaft  20 . Drawstring  80  secures the distal margin of membrane  30 . The mouth  27  of sheath  25  is expanded by the polyvinyl pull tab when drawn towards the end of shaft  20 .  
         [0069]    Circular array of cutting blades  55 , now encased by membrane  30 , is drawn into the mouth of snaring sheath  25  and removed from subcutaneous cavity  105 .  
         [0070]    In the preferred embodiment shown in FIG. 6, a plurality of guide struts generally designated  150  are advanced through a skin surface incision  126  and past a target tissue mass  115  via a tubular housing defining an extrication channel  26 . As shown in FIGS  7  and  8 , guide struts  150  are inserted through surface incision  126  and moved to a position to define a conically shaped desired excision margin  100  respecting the target tissue mass  115 , shown in FIG. 11. As shown in FIGS. 8 through 10, the extension and configuration of struts  150  from surface incision  126  past target mass  115  creates a gradually expanding subcutaneous retrieval path referred to as a conical penumbra  95 .  
         [0071]    As shown in FIGS. 11 through 13, an electro-cauterizing cutting snare  155  is advanced along guide struts  150 , creating a conically shaped excision margin.  
         [0072]    Referring to FIG. 14, the cutting snare  155  is advanced beyond the length of the guide struts  150  to where cutting snare  155  is drawn closed by pulling an integral drawstring  160  towards the exterior of the skin. As shown in FIGS. 15 through 17, mouth  27  of sheath  25  is advanced along the defined extrication channel  26  and expanded by pulling the polyvinyl pull tab which is not shown. As shown in FIGS. 18 through 24, guide struts  150  are enveloped by snaring sheath  25  and may be removed from subcutaneous cavity through extrication channel  26 .  
         [0073]    In one preferred practice of the invention as depicted in FIGS. 6 through 27 and using the apparatus shown therein, apparatus  200  includes a support conduit designated generally  202  and axially elongating skin cutting means  204  having a cutting blade  205  which is insertable through support conduit  202  as illustrated generally in FIG. 6. Skin cutting means  204  and particularly cutting blade  205  to make a suitable incision in the skin, preferably in the human breast designated generally  246  in FIG. 24 where the skin is designated  224  in the drawing figures including FIG. 6 and FIG. 24. The incision is made to provide access to a target tissue mass designated generally  228  in the drawings which has been previously identified preferably using x-ray mammographic techniques as being dangerous and hence to be removed.  
         [0074]    Once a skin incision, designated generally  248  in the drawings, has been made by skin cutting means  204  and appropriate use of cutting blade  205  thereof, skin cutting means  204  is preferably withdrawn axially through support conduit  202 , moving to the left in FIG. 6, and support means designated generally  207  and having a plurality of support members designated generally  206  is inserted axially through support conduit  202  and into the sub-cutaneous tissue  226  of the breast as indicated generally in FIG. 7, with the direction of travel of support means  207  indicated generally by arrow A in FIG. 7.  
         [0075]    As support members  206  of support means  207  are inserted into the sub-cutaneous tissue  226 , support members expand  206  radially due to influence of resilient spring means  210 , illustrated in dotted lines in FIG. 8 and forming a portion of support means  207  to a position where support members  206  define a conical penumbra enveloping target tissue mass  228 . The conical penumbra  208  defines planes of incision for removal of target tissue mass  228  and a medically advisable amount of surrounding sub-cutaneous healthy tissue  226 .  
         [0076]    As support members  206  radially diverge one from another due to the influence of resilient spring means  210 , remote tips  209  of support members  206  define a circle which in turn defines the base of conical penumbra  208 . Remaining, proximate ends of support members  206  are pivotally connected to a supporting shaft, not numbered in the drawings, for pivoting rotation thereabout in response to spring  210 .  
         [0077]    Once support members  206  have been deployed, into the position illustrated in FIG. 8, the target tissue mass is well within the conical penumbra defined by support members  206 .  
         [0078]    A pair of tissue cutting wire loops  214  are positioned about the bases of support members  206 , as illustrated generally in FIG. 9, and are supported by and emerge from respective support catheters  212 , also illustrated in FIG. 9. Support catheters  212  are sufficiently rigid that when force is applied in the axial direction to support catheters  212  is indicated by arrows B and B′ in FIG. 9, support catheters  212  move to the right in FIG. 9 advancing tissue cutting wire loops  214  along the outer periphery of support members  204  as depicted generally in FIG. 10.  
         [0079]    As support catheters  212  are moved to the right in FIGS. 9 and 10, additional lengths of tissue cutting wires  214  is supplied through support catheters  212  so that tissue cutting wires  214 , which are in the form of loops about the exterior surfaces of support members  206  as illustrated in FIG. 10, can enlarge as the circumference of the conical penumbra, measured about the slant surface of the conical penumbra defined by support members  206  as illustrated in FIG. 10, increases.  
         [0080]    Support catheters  212  are urged to the right in FIG. 10 until tissue cutting wire loops  214  pass the remote tips  209  of support members  206  and define a pair of essentially coincident and in any event concentric circles forming the base of conical penumbra  208 .  
         [0081]    Once tissue cutting wire loops  214  have reached this position due to movement of support catheters  212 , the wire forming tissue cutting wire loops  214  are drawn to the left, through respective support catheters  212 . This causes the respective tissue cutting wire loops  214  each to cinch together as the wires are withdrawn as indicated generally by arrows C, C′ in FIG. 11. As the tissue cutting wires are drawn to the left in FIG. 11 through respective support catheters  212 , the wire loops each cinch together thereby cutting circular incisions through the sub-cutaneous tissue; this action is illustrated generally in FIG. 11 where the respective tissue cutting wire loops are shown partially, but not completely, cinched. Two wire loops are preferable, for symmetrical application of force.  
         [0082]    Once tissue cutting wire loops  214  have been completely cinched and the wires withdrawn to the position illustrated in FIG. 12 by continually drawing the respective tissue cutting wires  214  in the directions indicated by arrows D, D′ in FIG. 12, the conical penumbra  208  defines planes of incision created by action of tissue cutting wire loops  214  where those planes of incision are shown in dotted lines in FIG. 12. Note that two dotted lines are shown at the extreme right of FIG. 12 to indicate that two circular planar incisions created by action of respective tissue cutting wire loops  214 . Desirably, these two circular planar incisions are essentially congruent one with another.  
         [0083]    Once tissue cutting wire loops  214  have been completely withdrawn into the position illustrated in FIG. 12, a suitable tissue containment bag structure  216  is advanced outwardly of support conduit  202 , around the outer periphery of support means  207  and particularly support members  206 . Tissue containment bag  216  preferably has a pair of drawstrings  218 , which may be metal, suture material, suitable plastic monofilaments and the like, which are sewn or threaded into tissue containment bag  216  proximate the vertical right-hand margin thereof appearing in FIG. 13. Drawstrings  218  have extremity portions  219  illustrated in FIG. 13.  
         [0084]    Once tissue containment bag  216  has been advanced so that its margin  217  has traveled inwardly with respect to the breast past the remote tips  209  of members  206 , to the position generally corresponding to the base of conical penumbra  208 , drawstring extremities  219  are pulled to the right in FIGS. 13 and 14, thereby causing looped drawstrings  218 ,  218 &#39;to close margin  217  of bag  216 , causing margin  217  to circularly gather as shown in FIG. 14.  
         [0085]    Once margin  217  of bag  216  has been circularly gathered thereby effectively closing bag  216  about the target tissue mass  228  of interest, an expandable sheath  230  is advanced through the interior of support conduit  202  about tissue containment bag  216  with expandable sheath  230  moving in the direction indicated by arrow F in FIG. 15. Expandable sheath  230  has a pleated expandable portion  231 , which is resilient and seeks to expand radially outwardly to relieve internal stresses such that upon expandable portion  231  reaching terminus  203  of support conduit  202  which is within sub-cutaneous tissue  226 , expandable portion  231  expands radially into the configuration illustrated generally in FIG. 16. Expandable portion  231  of sheath  230  is preferably pleated, as depicted in FIG. 17.  
         [0086]    Expandable sheath  230  and particularly expandable portion  231  thereof provides support in the form of radially inwardly directed force on tissue containment bag  216  as bag  216  with target tissue mass  228  enveloped therein is pulled to the left in FIGS. 16, 19 and  20  as indicated generally by arrows G in FIG. 19 and arrow H in FIG. 20. The radially inward force provided on tissue containment bag  216  and target tissue mass  228  contained therein by expandable sheath  230 , as tissue containment bag  216  is pulled to the left in FIG. 19, compresses tissue mass  228  into a smaller volume and essentially squashes tissue mass  228  into a longitudinally elongated form for passage through support conduit  202 . Application of the radial force to tissue mass  228  reduces the transverse cross-sectional dimension of tissue mass  228  to at least the diameter of support conduit  202  as tissue containment bag  216  is drawn through the funnel-shaped expandable portion  231  of sheath  230  and into the interior of support conduit  202 . Once bag  216  and tissue mass  228  contained therein have been removed from the sub-cutaneous tissue, expandable sheath  230  may be removed by pulling it in the direction indicated by arrow H in FIG. 20.  
         [0087]    Optionally, while expandable sheath  230  is in position and perhaps only part way removed from the resected area of interest, a medicament bag  232  may be inserted into the resected area through the interior of support conduit  202  and through expandable sheath  230 , as indicated in FIG. 21. This may provide means for supplying radioactive gas to provide radiation therapy to the resected area. Additionally, a radiographic marker depicted as  236  may be implanted into the resected area of interest, using the balloon or otherwise while expandable sheath  230  remains in the area of the resection. As an additional option while expandable sheath remains in position thereby maintaining a void in the resected area of the sub-cutaneous tissue, liquid medication indicated schematically as  234  in FIG. 22 may be supplied to the resected area. In such case expandable sheath maintaining the resected tissue in a spaced-apart condition facilitates application of the liquid medication to all parts of the resected volume.  
         [0088]    Utilizing the method and apparatus as described hereinabove results in a small, tunnel like incision approaching the skin of the breast with a larger, resected mass being removed therefrom; the resulting internal incision is depicted  244  in FIG. 24.  
         [0089]    Support members  206  preferably have metallic tips to provide radiopaque characteristics as indicated by  230  in FIG. 23 and may also have metallic or other radiopaque marker bands indicated as  248  in FIG. 23. Central portions  242  of support members  206  are preferably radiolucent as indicated by the stippling in FIG. 23.  
         [0090]    In FIGS.  28  thorugh  30  the curring wire and bag are connected by hook and rod structure as illustrated.

Technology Classification (CPC): 0