Abstract:
A surgical biopsy apparatus for cutting tissue comprising a housing having a longitudinal axis, first and second members movable from a retracted position to an extended position with respect to the housing, a third member slidably positioned and extendable with respect to the first member, a fourth member slidably positioned and extendable with respect to the second member, and an electrocautery cutting wire slidable with respect to the third and fourth members to surround a region of tissue positioned between the third and fourth members to cut the tissue.

Description:
[0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 09/122,185, filed Jul. 23, 1998 which claims priority from U.S. provisional application No. 60/053,664, filed Jul. 24, 1997. The contents of both these applications are incorporated herein by reference. 
     
    
     
       BACKGROUND  
         [0002]    1. Technical Field  
           [0003]    This application relates to a surgical device for removing tissue and more particularly relates to a surgical tissue biopsy device insertable through a small incision in the body.  
           [0004]    2. Background of Related Art  
           [0005]    Over 150,000 women in the United States alone are diagnosed each year with breast cancer. A biopsy of breast tissue is indicated when a breast abnormality is found, allowing removal of the tissue and testing to determine whether the abnormality is malignant and further surgery is necessary. Early diagnosis and removal of cancerous tissue is critical for successful treatment as early detection greatly increases the chances of survival.  
           [0006]    Numerous devices are currently available for performing breast biopsies. These devices function to dissect a portion of the breast tissue and remove it from the body for pathology to determine whether the tissue is malignant.  
           [0007]    The most invasive procedure is referred to as open excisional biopsy. In this procedure, large tissue samples are surgically removed, requiring long recovery times, risking disfigurement of the breast, increased scarring and increased morbidity.  
           [0008]    In an attempt to overcome the disadvantages of open surgery, more minimally invasive instruments have been developed. One minimally invasive approach utilizes a percutaneous instrument referred to as a fine needle biopsy instrument. In this instrument, a needle and syringe are inserted directly through the breast into the target tissue, e.g. the lump, to remove a cell sample for pathology. One disadvantage of this technique is that numerous cell samples are required to be taken from the tissue to obtain a sufficient mass for testing, thereby requiring numerous needle sticks and increasing the time required for the procedure. Another disadvantage is that careful locational tracking of the tissue cells removed is required for accurate analysis. Also, with these devices there is a greater potential for false negatives due to the small sized specimens being removed without removal of sufficient surrounding areas of healthy tissue for comparison.  
           [0009]    Another type of minimally invasive device is referred to as core needle biopsy. This device has a spring actuated cutter and obtains a larger specimen than the fine needle biopsy instruments. The specimen is suctioned into a side window in the needle and then back through the proximal end of the needle. Although larger than fine needle biopsy instruments, these needles are still relatively small, e.g. 2 mm in diameter. Since typically removal of between five and twenty tissue cores of 2 mm in diameter and 20 mm in length is required for accurate pathology, five to twenty needle sticks into the patient of this 2 mm diameter needle is required. These devices also have the disadvantage that the spring force cutting action may displace malignant cells into the adjacent normal tissue. Also, the amount of false negatives can be high because of inadequate removal of surrounding healthy tissue. Like fine needle biopsy, success and accuracy of the procedure is skill dependent because the device must be maneuvered to various positions and these different positions accurately tracked.  
           [0010]    Another disadvantage common to both fine needle and core needle biopsy devices is that the entire lesion cannot be removed. Therefore, if the tests show the lesion is malignant, another surgery must be scheduled and performed to remove the entire lesion and surrounding tissue. Besides the additional cost and surgeon time, this can have an adverse psychological affect on the patient who must await the second surgical procedure.  
           [0011]    Some percutaneous devices, such as the Mammotome marketed by Ethicon, Inc., attempted to overcome some of these disadvantages of percutaneous devices by enabling multiple specimens to be removed with a single needle stick. The specimens are removed from the proximal end of the needle by a vacuum. Although overcoming some disadvantages such as reducing the number of needle sticks, the Mammotome still fails to overcome many of the other drawbacks since careful tracking is required, success is skill dependent, and a second surgery is necessary if the lesion is malignant, with the attendant expenses and trauma.  
           [0012]    In an attempt to avoid a second procedure, the ABBI instrument marketed by United States Surgical Corporation provided a larger needle so that the entire specimen and tissue margins could be removed. The extra tissue excised is achieved by a larger diameter cannula. The cannula removes breast tissue from the skin surface entry point to the interior region of the breast where the lesion is located. The advantage of this instrument is that if pathology indicates the tumor is malignant, then an additional surgical procedure is not necessary since the tumor and margins were removed by the large cannula. However, a major disadvantage of this instrument is that if pathology indicates the lesion is benign, then a large tissue mass would have been unnecessarily removed, resulting in more pain, a larger scar, and possible disfigurement of the breast. Thus, ironically, the instrument is more beneficial if the tumor is malignant, and disadvantageous if the tumor is benign. In either case, the instrument has the further disadvantages of causing additional bleeding because of the large incision and requiring closure of a larger incision, thereby increasing scarring, lengthening patient recovery time, and adding to the cost, time and complexity of the procedure.  
           [0013]    It would therefore be advantageous to provide a surgical breast biopsy device which can access the targeted lesion through a small incision but be able to remove the entire lesion and margin, thereby avoiding the necessity for a second surgery. Such device would advantageously reduce the risk of cancer seeding, provide more consistent testing, reduce surgery time, reduce bleeding, and minimize disfigurement of the patient&#39;s breast.  
         SUMMARY  
         [0014]    The present invention overcomes the foregoing deficiencies and disadvantages of the prior art. The present invention provides a surgical biopsy apparatus for cutting tissue comprising a housing having a longitudinal axis, first and second members movable from a retracted position to an extended position with respect to the housing, a third member slidably positioned and extendable with respect to the first member, a fourth member slidably positioned and extendable with respect to the second member, and an electrocautery cutting wire movable with respect to the third and fourth members to surround a region of tissue positioned between the third and fourth members to cut the tissue.  
           [0015]    The apparatus preferably further includes a tissue retrieval bag movable with respect to the third and fourth members and movable from a retracted position within the housing to an extended position distally of the housing to surround a region of tissue positioned between the third and fourth members to remove the cut tissue.  
           [0016]    The apparatus preferably further comprises a first carrier slidably positioned over the first and third member, wherein the first carrier supports and advances the electrocautery wire and a suture for closing the tissue retrieval bag.  
           [0017]    Preferably the first and second members move radially outwardly away from the longitudinal axis of the housing and the third and fourth members initially move radially outwardly away from the longitudinal axis followed by movement inwardly towards the longitudinal axis. The third member is preferably telescopingly received within a first channel in the first member and the fourth member is preferably telescopingly received within a second channel in the second member.  
           [0018]    The present invention also provides a surgical biopsy apparatus for cutting a tissue mass comprising a housing, a plurality of first members extendable with respect to the housing and movable in a first direction at a first angle to the longitudinal axis of the housing, a plurality of second members movable with respect to the first members in a second direction different than the first direction and at an angle to the first angle, and a cutting wire movable longitudinally with respect to the first and second members to cut the tissue mass.  
           [0019]    The apparatus preferably includes a tissue retrieval bag movable longitudinally with respect to the first and second members to remove the tissue mass cut by the cutting wire. Preferably, a loop of the cutting wire and a mouth of the tissue retrieval bag are enlarged by the plurality of first and second members.  
           [0020]    The apparatus may include a marker supported within the housing and insertable into the tissue mass, the marker composed of shape memory material and the first and second members surrounding the marker. The first and second members may also be composed of shape memory material.  
           [0021]    The present invention also provides a surgical biopsy apparatus comprising a housing, a plurality of members advanceable with respect to the housing to provide a boundary for an area of tissue to be removed, a cutting wire loop advanceable with respect to the plurality of members to cut the area of tissue and/or a tissue retrieval bag advanceable with respect to the plurality of members to remove the area of tissue. Preferably, the cutting wire loop and/or a mouth of the tissue retrieval bag is moved to a larger diameter as it is advanced with respect to the members. Preferably at least one carrier is provided which is advanceable over one of the plurality of members to advance the cutting wire and the tissue retrieval bag toward the target tissue.  
           [0022]    The apparatus may also include an ultrasonic transducer at a distal end of the housing to enhance ultrasound imaging during the biopsy procedure.  
           [0023]    The present application also provides a method for removing a tissue mass for biopsy comprising inserting a cannula to a position proximal of the target tissue mass, advancing a plurality of tissue penetrating members from the cannula to an angular position to create a boundary area around the tissue mass, and advancing an electrocautery cutting wire with respect to the tissue penetrating members to surround the tissue mass defined within the boundary area.  
           [0024]    The method may further comprise the step of advancing a tissue containment bag with respect to the tissue penetrating members to encapsulate the cut tissue mass for removal, wherein the cutting wire and tissue containment bag are advanced substantially simultaneously.  
           [0025]    A method for performing breast biopsy is also provided comprising inserting into breast tissue a housing having a diameter smaller than a diameter of the tissue to be biopsied, advancing penetrating members through the breast tissue to create a tissue boundary area having a transverse cross-sectional length greater than the diameter of the housing, and advancing a cutting wire so a loop of the cutting wire moves to a diameter greater than the diameter of the housing. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]    Preferred embodiment(s) of the present disclosure are described herein with reference to the drawings wherein:  
         [0027]    [0027]FIG. 1A is a perspective view of the biopsy apparatus of the present invention in the initial position;  
         [0028]    [0028]FIG. 1B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 1A showing the outer (female) rails in the retracted position;  
         [0029]    [0029]FIG. 2A is a perspective view of the apparatus of FIG. 1 showing the outer and inner (male) rails in the fully deployed (advanced) position;  
         [0030]    [0030]FIG. 2B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 2A;  
         [0031]    [0031]FIG. 3A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position;  
         [0032]    [0032]FIG. 3B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 3A;  
         [0033]    [0033]FIG. 4A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position and the inner rails slightly advanced from within the outer rails;  
         [0034]    [0034]FIG. 4B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 4A;  
         [0035]    [0035]FIG. 5A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position and the inner rails partially advanced from within the outer rails;  
         [0036]    [0036]FIG. 5B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 5A;  
         [0037]    [0037]FIG. 6A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position and the inner rails further advanced to an intermediate position;  
         [0038]    [0038]FIG. 6B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 6A;  
         [0039]    [0039]FIG. 7A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position, the inner rails in the fully deployed (advanced) position, and the carriers initially advanced over the outer rails; (the cutting wire, suture, and bag being removed for clarity);  
         [0040]    [0040]FIG. 7B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 7A;  
         [0041]    [0041]FIG. 8A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position, the inner rails in the fully deployed position, and the carriers partially advanced over the inner rails past an intermediate position;  
         [0042]    [0042]FIG. 8B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 8A;  
         [0043]    [0043]FIG. 9A is a perspective view of the apparatus of FIG. 1 showing the outer rails in the fully deployed position, the inner rails in the fully deployed position, and the carriers extended over the inner rails to the fully deployed (advanced) position;  
         [0044]    [0044]FIG. 9B is an enlarged perspective view of the distal end portion of the apparatus of FIG. 9A;  
         [0045]    [0045]FIG. 10 is a longitudinal sectional view illustrating the interaction of the deployment rings, rails and carriers when the apparatus is in the initial position;  
         [0046]    [0046]FIG. 11 is an enlarged view of a portion of the apparatus of FIG. 10 showing the proximal deployment rings for advancing the rails;  
         [0047]    [0047]FIG. 12 is an enlarged view of a portion of the apparatus of FIG. 10 showing the distal deployment ring for advancing the carriers;  
         [0048]    [0048]FIG. 13 is a longitudinal sectional view illustrating the interaction of the deployment rings, rails and carriers when the apparatus is in the fully deployed position;  
         [0049]    [0049]FIG. 14 is an enlarged view of a portion of the apparatus of FIG. 13 showing the interaction of the deployment rings, rails and carriers;  
         [0050]    [0050]FIG. 15 is an enlarged perspective view of the distal end of the apparatus of FIG. 13;  
         [0051]    [0051]FIG. 16 is a further enlarged view of the distalmost portion of the apparatus of FIG. 15 illustrating the carriers fully advanced over the inner rails;  
         [0052]    [0052]FIG. 17A is an enlarged transverse cross-sectional view showing engagement of the lock with the pin and carriers;  
         [0053]    [0053]FIG. 17B is a further enlarged view of a portion of the apparatus shown in FIG. 17A;  
         [0054]    [0054]FIG. 18A is an enlarged longitudinal sectional view showing the interaction of the pin, lock and rails in the deployed position of the apparatus;  
         [0055]    [0055]FIG. 18B is an enlarged sectional view, cut in the longitudinal and transverse planes showing the interaction of the pin, lock and catheter in the deployed position of the apparatus;  
         [0056]    [0056]FIG. 19 is an enlarged view of the apparatus of FIG. 1 showing a first embodiment of the carriers for supporting the cutting wire and suture;  
         [0057]    [0057]FIG. 20 is an enlarged view of two of the carriers of FIG. 19 shown supporting the cutting wire and suture;  
         [0058]    [0058]FIGS. 21A and 21B are enlarged front and rear views, respectively, of the carriers of FIG. 19 showing the cutting wire and suture extending through the respective openings;  
         [0059]    [0059]FIG. 22 is an enlarged view of an alternate embodiment of the carrier having hooks to retain the cutting wire;  
         [0060]    FIGS.  23  is a perspective view of an alternate embodiment of the apparatus of the present invention having a wire loop tissue marker, wherein the apparatus is shown with the marker deployed, the outer rails fully deployed, and the inner rails in the retracted position;  
         [0061]    [0061]FIG. 24 is an enlarged view of the distal end of the apparatus of FIG. 23 showing the outer rails in the fully deployed position, the inner rails in the fully deployed position, and initial advancement of the carriers to advance the cutting wire, suture and tissue containment bag;  
         [0062]    [0062]FIG. 25 is a top perspective view of the apparatus having an alternative mechanism for advancing the rails and carriers;  
         [0063]    [0063]FIG. 26 is a bottom perspective view of the apparatus of FIG. 25;  
         [0064]    FIGS.  27 - 34  are perspective views illustrating the method of using the apparatus of the present invention for excising breast tissue, wherein:  
         [0065]    [0065]FIG. 27 illustrates the apparatus of the present invention approaching the breast to access the lesion;  
         [0066]    [0066]FIG. 28 illustrates the cannula of the apparatus inserted through an incision in the breast in line with the lesion;  
         [0067]    [0067]FIG. 29 illustrates the cannula inserted through an incision in the breast and the outer rails deployed proximally of the lesion;  
         [0068]    [0068]FIG. 30 illustrates the inner rails deployed to an intermediate position and partially encircling the lesion;  
         [0069]    [0069]FIG. 31 illustrates the inner rails fully deployed to encircle the lesion;  
         [0070]    [0070]FIG. 32 illustrates partial deployment of the carriers to advance the cutting wire, suture and tissue retrieval bag;  
         [0071]    [0071]FIG. 33 illustrates the carriers fully deployed with the tissue retrieval bag encircling the excised tissue;  
         [0072]    [0072]FIG. 34 illustrates the apparatus with the tissue encapsulated in the retrieval bag withdrawn from the breast;  
         [0073]    [0073]FIG. 35 is a perspective view of the apparatus inserted in a different orientation through an opening in a breast compression plate; and  
         [0074]    [0074]FIG. 36 is a perspective view of an alternate embodiment of the apparatus of the present invention having a transducer for imaging. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0075]    Referring now in detail to the drawings where like reference numerals identify similar or like components throughout the several views, the surgical apparatus for removing tissue is designated generally by reference numeral  10  in FIG. 1. The apparatus  10  of the present invention is particularly designed for removing breast tissue, however use of the apparatus for removal, i.e. biopsy, of other body tissue is contemplated.  
         [0076]    Referring to FIGS. 1A and 2A, apparatus  10  has a housing or cannula  12 , a series of deployment rings  20 ,  30 ,  40 , and a handle portion  14 . The ring  20  deploys outer (female) or first rails  50  and ring  30  deploys inner (male) or second rails  60 . As shown, outer rails (or outer tissue penetrating members)  50  and second rails (or inner tissue penetrating members)  60  are deployed from an initial position retracted within lumen  18  of cannula  12  as shown in FIGS. 1A and 1B to a deployed position where outer rails  60  encircle the tissue to be biopsied. The tissue is then severed and removed in the manner described below. As will be appreciated, the apparatus  10  enables removal of a lesion through a relatively smaller incision since the cannula  12  determines the size of the entry incision to the target site, and the rails  60  deploy radially outwardly defining an area having a diameter larger than the diameter of the cannula, thereby allowing a larger area/volume of tissue to be removed.  
         [0077]    Cannula or housing  12  can be composed of two separate cannulas: a proximal cannula  13  extending from conically shaped handle portion  14  and a reduced diameter cannula  16  extending distally from proximal cannula  13  and beginning at plastic interface  13   a . Alternatively, cannula  12  can be composed of a single cannula having a larger diameter proximal portion (like cannula  13 ) and a smaller diameter distal portion (like cannula  16 ). A portion of cannula  16  or of the reduced diameter cannula portion is configured for insertion into the patient&#39;s body.  
         [0078]    Cannula  13  preferably has a diameter D 1  of about 13 mm and cannula  16  preferably has a diameter D 2  of about 10mm. Clearly other diameters are contemplated which can preferably range from about 30 to about 7mm. Elongated slots  17   a  and  17   b  accommodate the respective pins of deployment rings  20 ,  30  and  40  in the manner described below. A pair of identical slots is formed on the opposite side of cannula  13  to accommodate the second pins of the deployment rings  20 ,  30  and  40 .  
         [0079]    As noted above, in the initial position, the outer rails  50  are fully retracted and housed within channel  18  of reduced diameter cannula  16  as shown in FIGS. 1A and 1B. Outer rails  50  have a central lumen  52  for telescopingly receiving inner rails  60 . Thus, inner rails  60  are likewise retracted within cannula  16  in the initial position of the apparatus  10 .  
         [0080]    In this initial position shown in the sectional views of FIGS.  10 - 12 , first and second proximal deployment rings  20  and  30  are in the proximalmost position adjacent handle portion  14  and distal deployment ring  40  is in its proximalmost position. A pair of pins  22 , preferably spaced 180° apart, extends through respective apertures  24  in ring  20  to engage ring-like slug  25 . Slug  25  has a pair of radial openings  21  to frictionally receive metal locks  23 , and locks  23  have openings  26  to receive pins  22 . In this manner, ring  20  is operatively attached to slug  25 . The other radial openings  21 , which although do not receive pins  22 , have locks  23  seated therein.  
         [0081]    Slug  25  also has a series of axial openings  28 , corresponding in number to the number of outer rails  50 , e.g. six. Outer rails  50  extend through these axial openings  28  in slug  25  and are affixed to locks  23 . That is, locks  23  have a pair of spaced apart legs or tabs  29  (see also FIG. 18A) which frictionally engage notches at the proximal end of outer rails  50 . In this manner, rails  50  are connected to slug  25  by frictional engagement with lock  23 . Thus, when pins  22  (and ring  20 ) are slid forward in slot  17   a , slug  25  and operatively connected outer rails  50  are advanced.  
         [0082]    In a similar manner, ring  30  has a pair of pins  32  extending through respective apertures  34  to engage ring-like slug  35  and ring  40  has a pair of pins  42  extending through apertures  44  to engage ring-like slug  45 . Slugs  35  and  45 , like slug  25 , frictionally receive locks  33 ,  43  within radial openings  36 ,  46 , and have a series of axial openings  38 ,  48 , to receive the inner rails  60  and carriers  70 , respectively. The number of openings  38 ,  48  corresponds to the respective number of rails  60  and carriers  70 . Locks  33  and  43  have openings  31 ,  41  to receive and secure the pins  32 ,  42 . In this manner, rings  30  and  40  are operatively connected to slugs  35  and  45 . Locks  33  and  43  also have tabs  39 ,  49  to receive the respective notches in the proximal portion of the rails  60  and carriers  70 . Thus, rings  30 ,  40  are operatively connected to rails  60  and carriers  70 , respectively, for deployment thereof. (Engagement of lock  43  with the notches  73  of carriers  70  is best seen in FIGS. 17B and 18B).  
         [0083]    To deploy the outer rails  50 , proximal deployment ring  20  is slid distally to advance slug  25 , carrying the rails  50  distally to advance from channel  18  of cannula  16  to the deployed position as shown in FIGS. 3A and 3B. (The pins in these FIG. as well as FIGS.  4 - 9  have been removed for convenience). Edge  19  of slot  17   a  functions as a positive stop to limit travel of proximal ring  20 . As can be appreciated, in this position, rails  50  extend radially outwardly with respect to a longitudinal axis L of cannula  16 . In this position, rails  50  can direct inner rails  60  upwardly and outwardly with respect to the reduced diameter cannula  16 .  
         [0084]    The outer rails  50  can have blunt tips as shown, or alternatively, to reduce the penetrating forces, can have more sharpened tips or beveled edges (described below) to facilitate cutting through tissue as they are advanced. Also, although six outer rails  50  are shown, a fewer or larger number of rails could be provided. Outer rails  50  are preferably composed of shape memory material with their memorized shape of that shown in FIG. 3B.  
         [0085]    Once the outer rails  50  have been deployed, proximalmost deployment ring  30  is linearly advanced to advance the inner rails  60  from within lumen  52  of outer rails  50 . As shown in FIGS.  4 - 5 , as ring  34  is slid distally within elongated slot  17   a  of channel  12 , slug  34  moves the inner rails  60  first radially outwardly with respect to the longitudinal axis L of cannula  16  at a similar angle to the angle of rails  50 , and then in a direction somewhat parallel to the longitudinal axis L to begin encircling the target tissue (FIGS. 6A and 6B). Further advancement of ring  34  moves the inner rails  60  inwardly toward longitudinal axis (as extrapolated) with their tips  64  coming together as shown in FIGS. 2A and 2B. Deployment ring  20  can act as a stop for advancement of deployment ring  30 . Alternatively, other means and mechanisms could be provided to provide a positive stop for advancement of the rings. In this fully advanced position, the rails  60  fully encapsulate, e.g., encircle the target tissue, defining a somewhat spherical tissue target region which can be of substantially circular or substantially elliptical transverse cross section. This target region has a diameter, defined by the distance D 3  between the opposing inner rails  60 , greater than diameter D 2  of the distal cannula  16  and diameter D 1  of proximal cannula  13 , thus enabling a larger region of tissue to be removed than the diameter of the incision. In a preferred embodiment, the distance D 3  is preferably slightly greater than about 3 cm, thereby allowing a 3 cm tissue region to be removed. It is also contemplated that other distances between the inner rails can be utilized.  
         [0086]    As with the outer rails  50 , inner rails  60  can have blunt tips as shown, or alternatively, to reduce the penetrating forces, can have sharper pointed tips or beveled edges to cut through tissue as they are advanced. FIGS. 30 and 32, discussed below, show by way of example beveled penetrating tips. Also, although six rails are shown, a fewer or larger number of rails could be provided. Inner rails  60  are preferably made of shape memory material which have a memorized shape of that shown in FIG. 2B.  
         [0087]    As noted above, outer and inner rails  50 ,  60  are preferably made of shape memory metal material, such as Nitinol, a nickel titanium alloy. To facilitate passage of the outer rails  50  through the housing, e.g.; cannula  16 , and facilitate passage of inner rails  60  through outer rails  50  into the tissue, cold saline is injected through or around the rails in their retracted position within cannula  16 . This shape memory material characteristically exhibits rigidity in the austenitic state and more flexibility in the martensitic state. The cold saline maintains the temperature dependent rails  50 ,  60  in a relatively softer condition as they are in the martensitic state within the cannula. This facilitates the exit of outer rails  50  from cannula  16  and the exit of inner rails  60  from outer rails  50  as frictional contact between the tips of outer rails  50  and the inner surface of cannula  16  and frictional contact between the tips of inner rails  60  and the inner walls of outer rails  50  would otherwise occur if the rails were maintained in a rigid, i.e. austenitic, condition.  
         [0088]    After deployment of the outer rails  50 , they are exposed to the warmer body temperature. This change in temperature causes the rails  50  to transition to their austenitic state to facilitate passage through the tissue. Similarly, after deployment of inner rails  60  from outer rails  50 , they are exposed to the warmer body temperature, thereby causing rails  60  to transition to their austenitic state to facilitate passage through tissue. A stopcock could be provided to ensure constant infusion of cold saline during advancement of the rails.  
         [0089]    Once the inner rails  60  have been fully deployed, the carriers or catheters  70  are deployed to advance cutting wire  86  and suture  82  which is attached to tissue containment bag  84 . (The cutting wire  86 , suture  82  and bag  84  are not shown in FIGS.  7 - 9  for clarity). More specifically, as shown in FIGS. 7A and 7B, movement of distal ring  40  in a distal direction, advances carriers  70  from channel  18  of cannula  16  as pins  42  extending through distal ring  40  slide within slot  17   b  to advance slug  44 .  
         [0090]    One embodiment of the carriers  70  for retaining and advancing the wire  86  and suture  82  is shown in FIGS.  19 - 21 . Each carrier  70  has a pair of cutting wire openings  74   a ,  74   b  and a pair of suture openings  72   a ,  72   b  positioned slightly proximally of openings  72   a ,  72   b  so that during advancement of carriers  70 , suture  82  will trail cutting wire  86 . One of the carriers  70  has a longitudinal slot  71  (see FIG. 18B) to enable the cutting wire  86  and suture  82  to extend proximally for attachment to a tension spring described in more detail below. For ease of manufacturing, each of the catheters  70  has a longitudinal slot so identical catheters can be made, however, optionally only one of the catheters  70  needs to be provided with the slot since the free end of the wire  86  and suture  82  can use a single passage proximally through the cannulas  13  and  16 .  
         [0091]    Suture  82 , as shown, is threaded through adjacent carriers  70  as it extends through opening  72   a  and exits opening  72   b  in one carrier  70 , then extends through opening  72   a  and out opening  72   b  in an adjacent carrier  70 , and continues through openings  72   a ,  72   b  of adjacent carriers  70  until it extends through all the carriers  70 . One end of the suture  82  is looped (reference numeral  83 ) around tissue containment bag  84  and attached thereto so that tensioning of the suture  82  cinches the open end of bag  84  to close the bag around the tissue severed by cutting wire  86 . The free end of suture  82  extends rearwardly through (e.g. through slot  71 ) or adjacent one of the carriers  70 , and extends proximally within with one end affixed to the cannula or handle. To enable tensioning of the suture  82 , preferably a constant force spring (not shown) is mounted at one end within cannula  12  or handle  14 . The free end of suture  82  is mounted to the other end of the spring so that advancement of the suture  82  by the carriers  70  unravels the spring and applies tension thereto, thereby applying tension to suture  82  to close the mouth of the tissue containment bag  84  as it is fully advanced.  
         [0092]    The cutting wire  86  is threaded through openings  74   a ,  74   b  in adjacent carriers  70  in a similar manner as suture  82 . That is, wire  86  extends into a carrier  70  through opening  74   a  and exits the carrier  70  through opening  74   b  where it can enter opening  74   a  in adjacent carrier  80 . The wire is formed into a loop  85  as shown, with the free end extending proximally through one of the carriers  70 , e.g. through longitudinal slot  71 , terminating within cannula  12 . A constant force spring (not shown) is mounted at one end within cannula  12  or handle  14  and at another end to the proximal end of cutting wire  86 . A connection wire (not shown) electrically connects cutting wire  86  to an RF frequency source for applying RF energy to the cutting wire  86 . As cutting wire  86  is advanced, it is held in tension by the spring.  
         [0093]    An opening  87  in carrier  70  has an internal diameter dimensioned to receive an outer rail  50  and an inner rail  60 . In this manner, carriers  70 , when advanced, can ride over rails  50 ,  60  to advance the cutting wire  86 , suture  82  and bag  84 . Cutting wire  86  is preferably mounted to a radiofrequency energy source so RF energy is applied as wire  86  is advanced distally with respect to the rails  60  to progressively cut and cauterize the tissue.  
         [0094]    Distal movement of ring  40  advances carriers  70  as they initially ride over the outer rails  50  as shown in FIGS. 7A and 7B, with opening  87  fitting over the outer surface of rails  50 . Further distal movement of ring  40  advance carriers  70  over inner rails  60  (FIGS. 8A and 8B) until they reach their final deployed position of FIGS. 9A and 9B. In this position, distal ring  40  is at the distalmost end of slot  17   b , with the edge  15  (see FIG. 1 A) of the slots  17   b  acting as a positive stop for pins  42  to limit forward travel of the ring  40  and slug  45 , and consequently limit travel of the carriers  70 . In this final position of the apparatus shown in FIGS. 9A and 9B, also shown in the enlarged views of FIGS. 15 and 16, the inner rails  60  and outer rails  50  are fully contained within channel  72  of carrier  70 . In this position, the cutting wire and the suture (with attached tissue containment bag) have traveled fully over the rails  50 ,  60  to the distal tips  64  of inner rails  60 .  
         [0095]    Note that as the carrier  70  is initially advanced over the rails, the diameter of the loop  85  of cutting wire  86  is enlarged since in this region outer rails  50  and inner rails  60  extend radially outwardly away from the longitudinal axis of the cannula  16 . As the carrier  70  is further advanced to intermediate region  63  of inner rail  60 , i.e. the region where the distance between opposing rails  60  peak and just before they begin their inward orientation towards the longitudinal axis of cannula  16 , the loop  85  will widen to its largest diameter, substantially equal to the diameter D 3  between opposing rails. This largest diameter of loop  85  defines the largest diameter of the tissue region being cut. As the wire  86  continues to advance past intermediate portion  63  of rails  60 , the diameter of the loop  85  reduces as the inner rails  60  extend inwardly towards the longitudinal axis L of cannula  16  and the distance between opposing inner rails  60  decreases. The spring attached at the proximal end applies constant tension to the wire  86  to reduce its loop size.  
         [0096]    The suture loop  83  of suture  82 , which slightly trails wire  86 , is expanded and reduced in a similar manner as wire loop  85  as the carriers  70  advance over the rails  50 ,  60 . That is, suture loop  83  increases in diameter, to thereby widen the opening  88  in tissue containment bag  84 , as carriers  70  advance to the intermediate region  63  of inner rails  60 . After advance past the intermediate region  63 , the suture loop  83  decreases in diameter to reduce the opening  88  in bag  84  as the spring at the proximal end of suture  82  applies constant tension to reduce the loop size. Thus, initial widening of suture loop  83  opens the mouth of bag  84  to receive the tissue mass severed by the cutting wire  86 , and reduction of the loop  83  as the suture  84  is pulled proximally by the tension of the aforedescribed spring closes the mouth of the bag  84  to entrap the severed tissue. The severed tissue can then be removed, fully enclosed in the bag, to prevent any undesired leakage. The opening, i.e. expansion, of the cutting wire  86  and the bag  84  is also described below in conjunction with the method of FIGS.  27 - 34 .  
         [0097]    Note that carriers  70  can have blunt tips as shown, or alternatively, to reduce the penetrating forces, can have pointed tips or beveled edges to cut through tissue as they are advanced. The number of carriers  70  can also vary, but preferably will be the same number as the number of outer and inner rails utilized. The carriers with the openings for the suture and wire can be integral with the elongated hollow member that rides over the rails or, alternatively, can be a separate component attached to the elongated members. For example, in FIG. 21B, the carrier  70  includes elongated carrier pusher  77  which can be integral with or attached thereto.  
         [0098]    It is also contemplated, that instead of being retained inside cannula  12 , e.g. cannula  16 , prior to deployment, the tissue retrieval bag could alternatively be mounted outside the cannula, e.g. outside cannula  16 . This would reduce the overall size requirements of the cannula since the additional room for the folded bag within the cannula would not be required.  
         [0099]    [0099]FIG. 22 illustrates an alternative embodiment of a carrier for retaining the cutting wire, suture and tissue retrieval bag. The bag and suture are mounted in a similar fashion as in the embodiment of FIGS. 21. However, instead of openings through the carrier  70 , for the cutting wire, the carriers  70 ′ each have an eyelet  75  to retain the wire. The eyelets  75  are formed at the end of rods  76  which extending through longitudinal slot  71 . The free end of the wire  86  would extend through one of the longitudinal slots  71  in carrier  70  to a proximally positioned spring. This embodiment allows the entire region of the wire to be exposed to tissue. The suture is not shown for clarity but would extend through openings in the carrier in the identical manner as FIG. 21.  
         [0100]    In an alternate embodiment of FIGS. 23 and 24, a localization marker  110  can be utilized to identify the region and provide sonographic or x-ray visualization of the center of the tissue site. More specifically, apparatus  100  (only the distal portion is shown) contains a marker  110  having a wire  111  forming a wire loop  115 , which is preferably made of shape memory material such as Nitinol. In the retracted position, support tube  114  is contained within the cannula  112  and loop  115  is contained within support tube  114  in a substantially straightened configuration substantially aligned with the longitudinal axis of the support tube  114  and the straight portions of wire  111 . To mark the tissue site, support tube  114  is advanced from cannula  112 , and then wire  111  is advanced from channel  117  of support tube  114  so that wire loop  115  extends distally therefrom. Once advanced from support tube  114 , wire loop  115  returns to its memorized looped configuration of FIG. 23. A sharpened tip  119  facilitates insertion. Also, cold saline is injected into tube  114  as described above, thereby decreasing the frictional contact with the inner wall of tube  114  to facilitate advancement of the wire.  
         [0101]    Wire loop  115  provides an indication via imaging or other visualization techniques of the target tissue, and more particularly a verification of the center of the target tissue. The rails  160  can then be advanced to encircle the wire marker  110  as shown in FIG. 24.  
         [0102]    In all other respects, the apparatus  100  of FIGS. 23 and 24 is identical to apparatus  10  of FIGS.  1 - 22 , as it includes outer rails  150 , inner rails  160 , carriers  170 , a suture  182  attached to tissue containment bag  184 , and a RF wire  186 . The rails  150 ,  160  and carriers  170  are advanced in the same manner as in apparatus  10  and therefore are not described again.  
         [0103]    It is also contemplated that the wire marker can be used as confirmation of the position of the deployed inner and outer rails  50  and  60 . A lockout can be provided that would allow deployment of rails  50  and  60  only after the wire marker is advanced, thereby aiding the positioning of the rails with respect to the lesion.  
         [0104]    Methods of utilizing the apparatus of the present invention for excising a lesion from the breast will now be described. It should be appreciated that the apparatus can be deployed either manually as in FIGS.  27 - 34 , or machine actuated as in FIG. 35.  
         [0105]    Turning first to the method illustrated in FIGS.  27 - 34 , in this method, the breast is not compressed and the apparatus, designated generally by reference numeral  200 , is deployed manually to access the target lesion and remove the lesion. Apparatus  200  is identical to apparatus  10  of FIGS.  1 - 21  except for the way the cutting wire is mounted to the carrier and the provision of beveled tips on the outer rails. The cutting wire is mounted to the apparatus via eyelets in the manner shown in FIG. 22. Consequently, the apparatus  200  has been labeled with reference numerals in the “ 200 ” series to correspond to the double digit reference numerals of apparatus  10 . Mounting pins have also been removed for convenience.  
         [0106]    Gripping handle portion  214 , apparatus  200  is inserted through incision “i” in the breast to access tissue lesion “t”. In this position, deployment rings  220 ,  230  and  240  are in their proximalmost positions in respective slots  217   a ,  217   b  with the outer (female) rails  250 , inner (male) rails  260 , and carriers (catheters)  270  retracted within reduced diameter cannula  16 .  
         [0107]    The cannula is then advanced through the incision “i” as shown in FIG. 28, in alignment with the lesion “t”, with the rails  250 ,  260  and carriers  270  in the retracted position. Next, the outer rails  250  are advanced to the position of FIG. 29, still spaced proximally of lesion “t”. Outer rails have a sharpened edge  251  to facilitate passage through tissue. The edge could alternately be beveled to facilitate passage.  
         [0108]    Inner rails  260  are then advanced from within outer rails  250  to encircle the lesion “t” as shown in FIGS. 30 and 31. Note that inner rails have beveled tips  261  forming sharpened edges to facilitate passage through tissue. As appreciated, both outer rails  250  and inner rails  260  return to their memorized shape, corresponding to their positions in FIG. 31, as they exit from the cool saline within cannula  212  and are exposed to the warmer body temperature. Since the rails extend radially outwardly after insertion of the cannula, the diameter of the tissue region to be excised (which is preferably substantially circular in cross section) exceeds the diameter of the cannula. Stated another way, the size of the excised tissue region can be increased without requiring a corresponding increase in the size (outer diameter) of the cannula. The region encapsulated is substantially spherical in shape and is much larger than the lesion.  
         [0109]    Next, as shown in FIGS. 32 and 33, carriers  270  are advanced to advance cutting wire  286  and suture  282  extending around the mouth of tissue containment bag  284 . As cutting wire  286  is advanced by carrier  270  with respect to the outer rails  260 , RF energy is applied to the wire  286  to cut and cauterize the tissue surround the lesion “t”. As can be appreciated, the cutting wire  286  is progressively opened to a larger diameter as it is advanced to the intermediate region of the rails  260 , substantially corresponding to the diameter of the sphere defined by the inner rails  260 . This diameter is substantially larger than the diameter of the lesion “t” to be removed. Thus, not only is the entire lesion “t” removed, but also a safety margin of tissue, e.g., about 1 centimeter radially in all directions from the lesion, is excised. If the safety margin is about 1 centimeter radially, the area of tissue removed will be about  3  centimeters.  
         [0110]    Trailing cutting wire  286  is suture  282  and tissue containment bag  284 . Thus, suture  282  looped around the mouth of bag  284  progressively increases in diameter, thereby increasing the opening in the mouth of bag  284  as it is advanced to the intermediate region of outer rails  250 . Thus, as lesion “t” is excised, it enters the mouth of bag  284  and is captured therein. As the bag  284  completes its travel, i.e. the carrier  270  is advanced to the distal tips  261  of inner rails  260 , the mouth of the bag  284  is automatically closed by the tension of suture  282  around the mouth of bag  284  due to the proximally applied force of the spring attached to the free end of the suture as described above. Thus the excised tissue is fully captured within bag  284 . The lesion and area of surrounding tissue are withdrawn substantially intact for accurate pathology. Moreover, since sufficient margins have been removed, even if the tumor is malignant, a second surgery is not necessary. FIG. 34 illustrates apparatus  200  withdrawn from the breast with the tissue encapsulated within tissue containment bag  284 . The rails  250  and  260  are elastically deformable to enable compression of the specimen as the apparatus is withdrawn through the relatively small incision.  
         [0111]    [0111]FIG. 35 illustrates the use of the apparatus with machine controlled deployment. In the method of FIG. 35, the breast is compressed between compression plates P 1  and P 2  to facilitate imaging as well as access to the lesion “t.” Apparatus  300  is advanced in the orientation shown, by table mounted controls (not shown), through aperture A in compression plate P 2 . That is, apparatus  300  would be positioned on a table, and advanced in a horizontal direction toward lesion “t”. The inner and outer rails and carriers are then advanced by preset machine actuated controls which engage the deployment rings via pins (not shown) to excise and remove the lesion. This is achieved by mounting pins to the apertures  324 ,  334  and  344  in deployment rings  320 ,  330  and  340 . The pins (not shown) will then be advanced by the table mounted actuators to advance the rings and connected slugs to deploy the rails and carriers in the manner described above.  
         [0112]    The apparatus  400  of FIGS. 25 and 26 illustrates an example of machine controlled actuation similar to apparatus  300  of FIG. 35. This apparatus differs only in that it has sliders which optionally allow for manual advancement if desired. That is, instead of automated actuation, the surgeon can advance sliders  423 ,  433  and  443 , which have internal pins connected to the slugs in the same manner as described above.  
         [0113]    For machine actuation of apparatus  400 , pins  422 ,  432  and  442  would be placed within slots in the machine, either in the orientation of FIG. 25 or the orientation of FIG. 26, depending on the orientation of the table mounted controls. The machine would be preset for controlled advancement of the pins, which would advance the rails and carriers in the same manner as pins  22 ,  32  and  42  of apparatus  10  described above. Optionally, an adapter can be mounted to the table which in turn mounts the apparatus.  
         [0114]    In any of the foregoing embodiments of the biopsy apparatus of the present invention, the cannula can include a lumen for injection of drugs or agents to treat or destroy the target and/or surrounding tissue or to inhibit cell proliferation. The lumen can be a separate tube in the cannula, formed integral with the cannula or be the same lumen which contains the rails. Types of materials which can be injected include, for example, chemotherapeutic agents, cryogenic material, ablation fluid, heating fluid, etc. These materials can be delivered to the target region either before, after or during specimen removal.  
       Imaging  
       [0115]    [0115]FIG. 36 illustrates an embodiment of the apparatus which utilizes ultrasound to help guide and visualize the apparatus during insertion and use. Apparatus  500  is identical to apparatus  200  in all respects, except for the provision of ultrasonic transducer  501  (shown in phantom), and is therefore provided with corresponding reference numerals in the “ 500 ” series, Transducer  501  is positioned at the distal end of the apparatus  500 , and is wired to a conventional power supply S. The wire extends inside cannula  512  and exits the proximal end of handle portion  514  as shown. Monitor screen M is wired to power supply S to enable viewing via ultrasound of the surgical site.  
         [0116]    Currently, as is known, low ultrasound frequency provides increased ability to see a greater distance but at the expense of resolution. Conversely, high frequency provides greater (clearer) resolution but with a decreased ability to see distances. Thus, typically, since the ultrasound probe is placed outside the breast tissue, at a distance from the lesion, it must be used at a low frequency to ensure the lesion can be viewed. However, resolution suffers and difficulty in detecting the boundaries of the lesion could occur. Lower resolution also decreases the chances of detecting calcium which is often an indicator of the presence of abnormal growths, i.e. tumors. For this reason, the breast tissue is often compressed between compression plates to shorten the distance from the probe outside to the breast to the lesion. However, compression of the breast adds an additional step to the procedure and could distort the image and result in inaccurate lesion removal, especially if the lesion site is marked in a non-compressed condition of the breast.  
         [0117]    In the apparatus  500 , by placing the transducer at the end of the apparatus, the distance from the lesion is greatly reduced. This allows a higher frequency to be used which provides greater resolution and an increased ability to detect calcium. Also, by placement of the distal end of the instrument, the surgeon can view the lesion in an orientation aligned with the cannula, also facilitating vision.  
         [0118]    It should be understood that the use of a transducer at the tip of the instrument can be used in other biopsy devices.  
         [0119]    While the above description contains many specifics, those specifics should not be construed as limitations on the scope of the disclosure, but merely as exemplifications of preferred embodiments thereof. For example, the inner and outer rails can be reversed so that the set of rails which extends to encapsulate the lesion is positioned outside instead of inside, the initially deployed set of rails. Also, the cutting wire could be positioned outside rather than inside the rails. Additionally, although described for use for breast biopsy, the apparatus can be used to excise tissue in other areas of the body and in other surgical procedures. Those skilled in the art will envision many other possible variations that are within the scope and spirit of the disclosure as defined by the claims appended hereto.