Patent Publication Number: US-8532748-B2

Title: Devices useful in imaging

Description:
This application claims priority to U.S. Provisional Application 61/047,160 filed Apr. 23, 2008. 
    
    
     BACKGROUND 
     Biopsy samples have been obtained in a variety of ways using various devices. An exemplary biopsy device is the MAMMOTOME device from Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. Further exemplary biopsy devices are disclosed in U.S. Pat. No. 5,526,822, entitled “Method and Apparatus for Automated Biopsy and Collection of Soft Tissue,” issued Jun. 18, 1996; U.S. Pat. No. 6,086,544, entitled “Control Apparatus for an Automated Surgical Biopsy Device,” issued Jul. 11, 2000; U.S. Pub. No. 2003/0109803, entitled “MRI Compatible Surgical Biopsy Device,” published Jun. 12, 2003; U.S. Pub. No. 2007/0118048, entitled “Remote Thumbwheel for a Surgical Biopsy Device,” published May 24, 2007; U.S. Provisional Patent Application Ser. No. 60/869,736, entitled “Biopsy System,” filed Dec. 13, 2006; U.S. Provisional Patent Application Ser. No. 60/874,792, entitled “Biopsy Sample Storage,” filed Dec. 13, 2006; and U.S. Non-Provisional patent application Ser. No. 11/942,785, entitled “Revolving Tissue Sample Holder for Biopsy Device,” filed Nov. 21, 2007. The disclosure of each of the above-cited U.S. patents, U.S. Patent Application Publications, U.S. Provisional Patent Applications, and U.S. Non-Provisional patent application is incorporated by reference herein. While many of the foregoing biopsy devices are configured to obtain biopsy samples from breast tissue, biopsy samples may also be obtained from various other locations. 
     Various biopsy devices may be designed to work with X-ray, ultrasound, and magnetic resonance imaging (MRI) as imaging modalities. For instance, various components for interfacing biopsy devices with various imaging systems are disclosed in the following: U.S. Pub. No. 2005/0261581, entitled “MRI Biopsy Device,” published Nov. 24, 2005; U.S. Pub. No. 2005/0277829, entitled “MRI Biopsy Apparatus Incorporating a Sleeve and a Multi-Function Obturator,” published Dec. 15, 2005; U.S. Pub. No. 2005/0283069, entitled “MRI Biopsy Device Localization Fixture,” published Dec. 22, 2005; U.S. Pub. No. 2007/0167736, entitled “MRI Biopsy Apparatus Incorporating an Imageable Penetrating Portion,” published Jul. 19, 2007; U.S. Pub. No. 2006/0241385, entitled “Guided Disposable Fiducial for Breast Biopsy Localization Fixture,” published Oct. 26, 2006; U.S. Pub. No. 2006/0258956, entitled “MRI Biopsy Device,” published Nov. 16, 2006; U.S. Pub. No. 2007/0255168, entitled “Grid and Rotatable Cube Guide Localization Fixture for Biopsy Device,” published Nov. 2, 2007; and U.S. Pub. No. 2007/0255170, entitled “Biopsy Cannula Adjustable Depth Stop,” published Nov. 1, 2007; and US Pub No. 2008/0015429, “MRI Biopsy Device” published Jan. 17, 2008. The disclosure of each of the foregoing published patent applications is incorporated by reference herein. 
     It may be desirable in some settings to use one or more imaging modalities other than X-ray, ultrasound, or MRI before, during, or after a biopsy procedure. For instance, an alternative imaging modality may include positron emission tomography (PET) imaging. In a mammography context, such imaging may be referred to as positron emission mammography (PEM). Instead of scanning the entire body, PEM may be used as a special form of PET for imaging breasts and other small body parts. This may allow for a more detailed image of abnormal tissue. In a PEM context, the patient may be injected with an intravenous substance called FDG (fluorodeoxyglucose), which is a glucose analog, which may accumulate in glucose avid cells. This substance may carry a positron emitting radioactive isotope. One or more detectors may be used to capture emission of positrons emitted by such an isotope (e.g., by capturing resulting gamma photons) to ultimately produce an image. Alternatively, any other substances may be injected into a patient, as a tracing agent for PEM imaging or otherwise. An exemplary PEM system may include the PEM FLEX SOLO II system by Naviscan PET Systems, Inc. of San Diego Calif. 
     Another alternative imaging modality may include breast-specific gamma imaging (BSGI). In a use of BSGI, a patient may be injected with a radiotracer (e.g., Technicium isotope T-99), and a BSGI camera may be used to capture gamma radiation emitted by such a tracer. Cancerous cells may have a higher tendency to absorb certain gamma emitting radiotracers, which may result in cancerous lesions standing out under BSGI imaging. BSGI imaging may thus provide distinction between cancerous tissue and non-cancerous tissue based on cellular activity rather than being based on tissue density. An exemplary BSGI system may include the DILON 6800 by Dilon Technologies of Newport News, Va. 
     Various biopsy site marker devices are disclosed for use in marking biopsy sites. One or more marker devices are disclosed in U.S. Pub. No. 2005/0228311, entitled “Marker Device and Method of Deploying a Cavity Marker Using a Surgical Biopsy Device,” published Oct. 13, 2005; U.S. Pat. No. 6,996,433, entitled “Imageable Biopsy Site Marker,” issued Feb. 7, 2006; U.S. Pat. No. 6,993,375, entitled “Tissue Site Markers for In Vivo Imaging,” issued Jan. 31, 2006; U.S. Pat. No. 7,047,063, entitled “Tissue Site Markers for In Vivo Imaging,” issued May 16, 2006; U.S. Pat. No. 7,229,417, entitled “Methods for Marking a Biopsy Site,” issued Jun. 12, 2007; U.S. Pat. No. 7,044,957, entitled “Devices for Defining and Marking Tissue,” issued May 16, 2006; U.S. Pat. No. 6,228,055, entitled “Devices for Marking and Defining Particular Locations in Body Tissue,” issued May 8, 2001; and U.S. Pat. No. 6,371,904, entitled “Subcutaneous Cavity Marking Device and Method,” issued Apr. 16, 2002. The disclosure of each of the above-cited U.S. Pat. No. and U.S. Patent Application Publications is incorporated by reference herein. 
     SUMMARY OF THE INVENTION 
     The use of a biopsy device with PEM and/or BSGI may warrant features or techniques that are different from those used with other imaging modalities. For instance, with X-ray it may be desirable to have a radiopaque biopsy needle to be able to determine if the needle is in the correct location in the target tissue. To target in ultrasound, it may be desirable for a biopsy probe needle has to have a good amount of echogenecity to be visible in the modality. With MRI, the ability to see the biopsy needle in the breast may mean that there should be no artifact in the needle to affect the targeted tissue area. 
     In a PEM and/or BSGI context, it may be desirable to incorporate an isotope (e.g., FDG isotope, isotope T-99, etc.) into at least a portion of targeting device and/or a biopsy device used to obtain a tissue sample. The presence of such an isotope in the biopsy device may permit or facilitate targeting in tissue, such as by facilitating verification that a targeted lesion has been reached. Such an isotope may be incorporated in a variety of biopsy device or system components, including but not limited to a portion of a biopsy needle, an obturator, or various portions of a targeting set, as will be described in greater detail below. 
     A biopsy target assembly comprising a sleeve having a proximal end, a distal end, and a side opening positioned proximal of the distal end of the sleeve; and an elongate member advanceable in the sleeve, the elongate member carrying at least one isotope. The sleeve may be relatively flexible, and may have an open distal end. The elongate member may be relatively stiff, and may a tissue piercing distal tip. The isotope may be carried by the elongate member such that when the elongate member is advanced fully distally within the sleeve, the isotope is substantially aligned with the side opening in the sleeve. The isotope may be disposed a predetermined distance proximally of a distal end of the elongate member. 
     In another embodiment, the invention provides a biopsy target assembly. The assembly may include a guidance assembly; a sleeve mount positionable with respect to the guide assembly; a sleeve releasably supported on the sleeve mount; and a member advanceable in the sleeve, the member carrying at least one isotope. 
     In another embodiment, the invention provides a target assembly which includes a grid member forming part of a movable compression member for compressing a patient&#39;s breast. The biopsy target assembly may include a grid plate comprising a plurality of openings; a guide insertable in one of the grid plate openings, the guide having at least one guide passageway therethrough; a sleeve insertable in the guide passageway of the guide; and a member advanceable in the sleeve, the member carrying at least one isotope. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       It is believed the present invention will be better understood from the following description of certain examples taken in conjunction with the accompanying drawings, in which like reference numerals identify the same elements and in which: 
         FIG. 1  depicts a perspective view of an exemplary biopsy targeting assembly illustrating an isotope introducer comprising a relatively rigid member, such as an obturator rod, inserted into a sleeve having an open distal end and a side aperture, with the relatively rigid rod having an isotope portion generally aligned with the side aperture in the sleeve when the relatively rigid member is inserted into the sleeve; 
         FIG. 1A  depicts the relatively rigid member of  FIG. 1  positioned in the sleeve such that an isotope portion (shown in phantom) is aligned with a side aperture in the sleeve. 
         FIG. 2  depicts an exploded view of an alternative embodiment of a targeting assembly. 
         FIG. 2A  depicts an isotope introducer of the target assembly of  FIG. 2 . 
         FIG. 2B  depicts the target assembly of  FIG. 2  positioned in guide structure inserted in one of a plurality of openings in a positioning grid, such that a proximal portion of the target assembly is disposed on one side of the grid, and such that a distal portion of the target assembly comprising an isotope portion is disposed on the other side of the grid. 
         FIG. 2C  depicts a biopsy needle having a side tissue receiving opening, the biopsy needle extending through a guide structure inserted in a positioning grid, with a hollow cutter advanced distally in the needle to close the side tissue receiving opening, and with an introducer carrying an isotope portion advanced distally within the cutter to position the isotope in substantial alignment with the side tissue opening in the needle. 
         FIG. 3  depicts a perspective view of an introducer useful for positioning an isotope portion in or through a biopsy device, the introducer including a relatively flexible hollow tube such as the type used in flexible biopsy marker applications, and a relatively flexible elongate member slidably insertable in the flexible hollow tube, with the elongate member being sized and shaped to position the isotope portion at a predetermined distance along the flexible hollow member&#39;s length; 
         FIG. 3A  illustrates the elongate member positioned in the hollow tube, with the isotope portion shown in phantom and spaced a predetermined distance D from a closed, distal end of the hollow tube. 
         FIG. 3B  illustrates the relatively flexible hollow tube deformed through an angle A, such that the flexible hollow tube may be advanced along a non-linear path into a biopsy needle to position an isotope in substantial alignment with a side opening in the biopsy needle. 
         FIG. 4  depicts a perspective view of another embodiment of an introducer having a generally flexible shaft with an isotope portion disposed at a distal end thereof, such as by attaching the isotope portion to the distal end of the flexible shaft, or by inbedding or molding the istope portion in a distal end portion of the shaft; 
         FIG. 5  depicts a perspective view of an introducer comprising an istotope portion extending through a biopsy device, such that a proximal end of the introducer extends proximally from the proximal end of the biopsy device, and a distal end of the introducer associated with an isotope portion is disposed within an outer needle of the biopsy device; 
         FIG. 5A  illustrates a hollow cutter advanced with a biopsy needle to close off a side tissue opening in the needle, and an isotope advanced into the cutter and aligned with the side tissue opening. 
         FIG. 6A  depicts a top plan view of an exemplary biopsy needle incorporating an isotope; 
         FIG. 6B  depicts a lateral side cross-section of the biopsy needle of  FIG. 6A  showing a hollow cutter disposed within the biopsy needle and an isotope associated with a portion of the needle located below a side tissue receiving aperture in the needle. 
         FIG. 7  depicts a biopsy device incorporating an isotope disposed around at least a portion of a side tissue receiving opening in the biopsy needle; 
         FIG. 8  depicts a perspective view of an introducer having an elongate member in the form of a rod, the rod having an isotope in the form of a coating or decal positioned on the rod in spaced relationship from the distal end of the rod. 
     
    
    
     DETAILED DESCRIPTION 
     The following description of certain examples of the invention should not be used to limit the scope of the present invention. Other examples, features, aspects, embodiments, and advantages of the invention will become apparent to those skilled in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the invention. As will be realized, the invention is capable of other different and obvious aspects, all without departing from the invention. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive. 
       FIGS. 1 and 1A  depict one biopsy targeting assembly  50  in accordance with the present invention that may be used with PEM, PET, BSGI, or other nuclear imaging systems utilizing an isotope or other radiation emitting source. The assembly shown can include similar structures employed in a targeting assembly described in one of published U.S. patent applications as being used in an MRI setting, such as US 2007/0255168 and US 2008/0015429 incorporated by reference herein. In addition, the targeting assembly  50  of the present example shown in  FIG. 1  land  FIG. 1A  further includes an introducer  400  comprising an isotope, such as an isotope portion  420  (shown in Phantom in  FIG. 2 ) visible under one or both of PET, PEM, and/or BSGI, and/or any other nuclear based imaging system where an isotope is used to verify target location. 
     Referring to  FIGS. 1 and 1A , the targeting assembly  50  can include a sleeve assembly  100  supported by a sleeve mount  136 . The assembly  50  can also include a cradle assembly  60 . Cradle assembly  60  may provide support for a biopsy device having an outer biopsy needle and an inner cutter. Assembly  60  may also support the sleeve mount  136 , such as for motion along a direction into which the biopsy instrument needle and the sleeve  110  is to directed into tissue (z direction) indicated by arrow A in  FIG. 1 . Sleeve assembly  100  may include an enlarged distal end portion  140  which may releasably latch to sleeve mount  136 . The end portion  140  may include one or more internal seals for providing sealing around the elongate member  408  when the member  408  is inserted into the sleeve assembly  100 . The assembly may also include a cap  144  which may include a through bore for receiving member  408 , or alternatively cap  144  may cover an opening in end portion  140  when the introducer  400  is removed from the sleeve  110 . 
     In the embodiment shown, the sleeve assembly  100  comprises a sleeve  110  having an open distal end  114  and a side tissue receiving port  116 . Alternatively, the sleeve may have a closed distal end, or the sleeve may have an open distal end with no side aperture  116 . The sleeve  110  may be formed of any suitable metallic or non-metallic material. In one embodiment, the sleeve  110  is formed of biocompatible medical grade plastic. 
     The isotope introducer  400  shown may comprise a plunger  402 , and an elongate member  408 , which may be in the form of a hollow or substantially solid rod. The introducer  400  may further include a distal tissue piercing tip  410  disposed at a distal end of the member  408 . In those embodiments where member  408  includes a distal piercing tip  410 , it can be advantageous to have elongate member  408  be relatively stiff. By ‘relatively stiff’ in this context, it is meant that the tip  410  of the introducer  400  may be inserted into sleeve  110  in a generally straight line path and the tip  410  pressed or otherwise advanced into a tissue mass without breaking, buckling, or otherwise excessively deforming the introducer  400 . The introducer  400  may have a latch or other structure for releasably securing the introducer to the sleeve assembly  100 , either directly or indirectly. 
     The introducer  400  may be formed of any suitable metallic or non-metallic material, and in one embodiment may be formed of a relatively rigid medical grade, biocompatible plastic of sufficient compressive rigidity and strength to advance tip  410  into tissue. The introducer may be sized and shaped such that when the elongate member  408  is fully inserted into sleeve  110 , the distal tip  410  extends through the distal opening  114  of sleeve  110 , and the isotope portion  420  is generally aligned with the side tissue receiving port  116 , as shown in  FIG. 1A . The introducer  400  may be disposable, or may be adapted for repeated use. 
     The isotope portion  420  comprises one or more isotopes visible under one of PET and/or BSGI, and may additionally include other materials, such as one or more binder materials or encapsulating coatings for covering the one or more isotopes. The isotope portion  420  may comprise a liquid, a solid, a gas, or combinations thereof. The isotope portion may be disposed within the elongate member  408 , such as by being molded into the member  408 , or such as being disposed within a cavity within the member  408 . 
     The sleeve  110  shown in  FIGS. 1 and 1A  has a side tissue receiving opening  116  disposed proximally of the distal open end  114 . The opening  116  may correspond with a transverse (side) opening in a biopsy needle through which tissue is received. After the isotope portion  420  has been positioned in the sleeve  110 , the sleeve with isotope  420  may be positioned with a tissue mass, and imaged using PET and/or BSGI to determine the location of the side opening  116  with respect to the tissue mass. 
     The introducer  400  may then be removed from the sleeve  110 , and the biopsy device needle may be inserted into the sleeve such that the needle side opening is substantially aligned with the side opening  116 . A hollow cutter inside the biopsy probe may then be translated and rotated within the needle to sever tissue prolapsed or otherwise received (such as by being drawn in by vacuum) through the side opening  116  in the sleeve  110  and the side opening in the biopsy device. 
     The isotope introducer  400  in the example of  FIG. 1  is inserted in the sleeve  110 . The introducer  400  described above and shown in  FIG. 1  and  FIG. 1A  can perform as an obturator, such as while the sleeve  110  is inserted into tissue. Alternatively, a separate obturator may be provided and inserted with the sleeve into tissue, and the obturator may then be removed from the sleeve while the sleeve remains in tissue to be imaged, and the introducer  400  may be inserted into the sleeve  110 , such that isotope portion  420  is substantially aligned with the side opening  116  while the sleeve is in tissue. Still further, in another embodiment the isotope introducer  400  may be insertable into an otherwise separate obturator. 
     To the extent that the sleeve prevents certain portions of the isotope rod from being “visible” under an imaging modality, the side opening in the sleeve may provide a window through which the isotope rod may be more easily “seen” under the imaging system in use. Such visibility may thus help indicate the location of the sleeve&#39;s side opening, which may in turn indicate the location of tissue that would be captured by a biopsy device whose needle is inserted into the sleeve after the isotope rod is withdrawn. The location and alignment of the isotope with the side opening may thus provide targeting of tissue. 
     In some uses, the location of target tissue may be predetermined, the sleeve may be inserted to reach the target, and the sleeve  110  and introducer  400  may be viewed under PEM and/or BSGI to confirm proper placement of the side opening  116 . Alternatively, the position of the sleeve may be adjusted in real time, while viewing both a suspicious lesion and the location of the side opening  116  as indicated by the isotope rod showing through the transverse opening. 
     In accordance with one method of using the device in  FIGS. 1 and 1A , the method may include the steps of providing a composition to the patient which identifies or otherwise tags specific tissue mass cells (e.g. cancer cells) to be visible under PET and/or BSGI imaging, imaging the breast using PET and/or BSGI, determine the location of the tissue mass of interest, inserting the isotope introducer  400  into the sleeve assembly  100  to substantially align the isotope portion  420  with the side opening  116 , set a depth of insertion for the sleeve assembly (e.g. z stop) based on location of the tissue mass of interest within the breast, advance the sleeve assembly with introducer  400  into the breast, distal tip  410  first, and view or otherwise image the isotope portion  420  (and so side opening  116 ) with respect to the tissue mass of interest. 
       FIGS. 2 ,  2 A, and  2 B illustrate another embodiment of the present invention.  FIG. 2  illustrates a target assembly  500  comprising an obturator seal cap  510 , an isotope introducer in the form of obturator assembly  520 , and a sleeve assembly  560 . Obturator seal cap  510  may have a feature  512  adapted to lock and/or locate the cap  510  with respect to an obturator hub  522  of an obturator assembly  520 . 
     Obturator assembly  520  may include an obturator hub  522  having a feature  524  adapted to lock and/or locate the the obturator hub  522  with respect to the sleeve assembly  560 . An obturator shaft  526 , which may be hollow shaft, extends distally from hub  522  and may have a distal tissue piercing tip  530 . The obturator shaft  526  shown includes a surface feature  528 , which may be in the form of a recess, notch, or cavity, in which the isotope portion  540  may be disposed. The feature  528  as shown comprises a recess extending through a wall of the hollow shaft  526 , with recess  528  disposed proximally of the tip  530 , and the recess  528  may communicate with an internal lumen that extends distally from a proximal opening  523  of shaft  526 . The isotope portion  540  may comprise a solid, liquid, and/or gas disposed in the recess  528 , or may be a component molded or otherwise formed to fill or partially fill the recess  528 . 
     The sleeve assembly  560  shown in  FIG. 2  comprises a proximal sleeve base  562 , and a sleeve  564  having a proximal end  567  and the sleeve  564  extending distally from base  562 . The sleeve  564  is shown having a side opening  566  and a distal open end  568 , with a lumen extending between proximal end  567  and distal open end  568 . The sleeve assembly  560  may further comprise a duckbill seal  570  for providing a seal when obturator shaft  526  is removed from sleeve assembly  560 , a seal  572 , such as a wiper seal or lip seal for providing a seal around shaft  526  when the obturator shaft  526  is disposed within the sleeve assembly  560 , and a seal retainer  574  adapted to retain seals  570  and  572  within a bore in base  562 . 
       FIG. 2A  illustrates the isotope introducer, in the form of an obturator assembly  520 , with the obturator shaft  526  disposed within sleeve  564  with a bottom surface  527  of shaft  526  facing the opening  566  (surface  527  shown visible through opening  566  in  FIG. 2A ), such that recess  528  in the obturator shaft  526  (and the isotope portion  540 ) faces downward, away from the side opening  566  formed in the sidewall in the sleeve, and such that the isotope  540  is substantially aligned (longitudinally) with the opening  566 . 
     The obturator shaft  526  may be inserted into the sleeve  564  so that the tip  530  extends from open distal end  530  of sleeve  564  and the isotope  540  faces away from opening  566 . By inserting the shaft  526  into sleeve  564  such that the isotope portion  540  is substantially aligned with, but faces away from side opening  566  formed in a sidewall of sleeve  564 , tissue contact with the isotope portion may be avoided, and the need for an additional sleeve or protective cover between the isotope portion  540  supported by shaft  526  and the opening  566  is avoided. 
       FIG. 2B  illustrates the target assembly  500 , with sleeve assembly  560  supported in a grid member  580  having a plurality of openings  582  therethrough. The sleeve assembly  560  extends through an opening in a guide member  590  sized and shaped to be received in one or more of the openings  582 . The guide member  590  supports the isotope introducer/obturator and the sleeve assembly relative to the grid member  580 . Grid member  580  may be provide a portion of a breast compression member and/or be movably supported relative to the patient&#39;s breast. 
     In one method of using the device shown in  FIGS. 2 ,  2   a , and  2   b , the patients&#39;s breast may be imaged using PET and/or BSGI to determine the location (e.g. spacial coordinates such as x, y, z cartesion coordinates) of a target tissue lesion with respect to a reference frame. The guide member  590  may then be placed in one of the openings  582  based on the determined location (e.g. x, y coordinates) of the target tissue lesion. The obturator assembly may be positioned within the sleeve assembly such that the isotope portion  540  is substantially aligned with side opening  566  in the sleeve assembly, but with the isotope portion  540  facing downward, and substantially opposite opening  566 . 
     A z-stop device, such as depth ring stop  596  ( FIG. 2B ) may be employed to set the depth of insertion (z coordinate) of the side opening  566  and/or tip  530  into the breast. As the sleeve and obturator are inserted into the breast, the user may use PET and/or BSGI to view, in real time, the targeting set being inserted to the lesion site as it is penetrating the breast. 
     The bottom surface  527  of obturator shaft  526  and sleeve  564 , in combination, may act as a cover to prevent the isotope from coming into contact with the breast tissue (e.g., for sterility reasons). Once location is confirmed, then the obturator may be removed with the isotope, and the needle of a biopsy device may be inserted into the sleeve  564  to take tissue samples. 
     In other variations, the sleeve and/or obturator may include one or more isotope portions (e.g., near the distal end of the sleeve and/or obturator). Such isotope portions may be internal (e.g., impregnated, etc.) and/or external (e.g., coatings or stickers, etc.). 
       FIG. 2C  depicts another embodiment employing a grid  580 . In  FIG. 2C , a guide  590  is shown inserted in an opening in the grid  580 . The guide has a through bore sized and shaped to receive and support a biopsy needle  1200  inserted in the bore to extend through the guide  590 . 
     The biopsy needle  1200  shown in  FIG. 2C  is shown partially cut away to reveal a hollow cutter  1290  disposed within the needle  1200 , and the cutter  1290  is shown partially cut away to reveal an isotope introducer  300  disposed within the hollow cutter  1290 . 
     The needle  1200  is shown having a distal tissue piercing tip  1202  and a side tissue receiving opening  1276  disposed proximally of the tip  1202 . The biopsy needle  1200  is also shown having a plurality of depth (z-direction) indicating indicia  1204  on the outer surface of the needle. The depth indicating indicia  1204  can be generally equidistantly spaced apart along the longitudinal axis of the needle, and can take any suitable form, such as for instance lines, ribs, indentations, and/or score marks. The indicia can include numerical or color coded information for placement of the needle at a desired depth (z-coordinate) within the patient&#39;s breast. 
     In  FIG. 2C , the distal cutting edge  1292  of the cutter  1290  is shown advanced distally past the side opening  1276 , so as to close the side opening  1276  from the internal lumen of the needle  1200 . In one embodiment, the needle  1200  with side opening  1276  closed by cutter  1290  can be advanced through the guide  590  into the patient&#39;s breast. The isotope introducer  300  may then be advanced distally within the hollow cutter  1290  so that an isotope portion  340  associated with the distal end of the introducer  1290  is positioned in substantial alignment with the side opening  1276  of needle  1200 . The introducer  300  may be in the form of a relatively flexible or relatively rigid rod sized and shaped to pass through the hollow cutter  1290 . The isotope portion  340  may be disposed within the distal end of introducer  300  (as shown in phantom in  FIG. 2C ), or the portion  340  may be attached to the distal end of the introducer  300 . 
     The cutter  1290  as positioned in  FIG. 2C  may act as a shield or otherwise separate the isotope portion from direct contact with the patient&#39;s tissue. The position of the isotope portion  340 , aligned with the side opening  1276 , may be imaged using PET, PEM, BSGI, and/or any other suitable nuclear imaging procedure, to verify that the opening  1276  is positioned correctly with respect to the tissue mass of interest. If desired, the position of opening  1276  may be varied with respect to the tissue of interest in real time using the image information from the selected imaging procedure. Once the opening  1276  is positioned in the desired location, the introducer and isotope portion may be withdrawn from the cutter, and the cutter may be retracted proximally to position the cutter distal end  1292  at a position proximal of the opening  1276 . Vacuum may be provided through the cutter and/or a separate vacuum lumen to draw tissue into the opening  1276 . The cutter may then be advanced distally to sever the tissue drawn into the opening  1276 . 
       FIGS. 3 and 3A  illustrate an isotope introducer assembly  600  according to another embodiment of the present invention, in which the assembly  600  may be used to introduce and/or position an isotope with respect to a biopsy device. The introducer assembly  600  shown in  FIG. 3  includes a sleeve  610 , a grip  620  disposed at or adjacent to an open proximal end  612  of the sleeve  610  (grip not shown in  FIG. 3A ), and an introducer component  630  comprising a plunger  632  and an elongate introducer member in the form of a rod  634 . The sleeve  610  and the rod  634  can both be relatively flexible. 
     By “relatively flexible” in this context it is meant that the sleeve  610  and insertion rod  634  may be resiliently bent or otherwise resilient deformed through an angle of at least 60 degrees without breaking the sleeve  610  (or the member  634  within the sleeve) to permit the sleeve  610  and member  634  to be inserted along a non-linear path, such as for insertion in a biopsy device. In one particular embodiment, the sleeve and insertion rod may be resiliently bent through an angle of at least about 135 degrees without breaking. 
       FIG. 3B  illustrates a sleeve  610  deformed through an angle A of between about 60 and 90 degrees, for insertion in a proximal end of a biopsy needle  1200 , with a distal cutting edge  1292  of a hollow cutter  1290  retracted proximally from the proximal end of the needle  1200 . The sleeve  610  can be in the form of a thin wall hollow tube having an open proximal end  612  and a closed distal end  614 . As shown in  FIG. 3A , the sleeve  610  can have an internal lumen  618  into which member  634  may be slidably inserted. 
     An isotope portion  640  may be operatively associated with a distal portion of member  634 . For instance, in  FIG. 3A  the isotope portion  640  (shown in phantom) may be disposed within the member  634 , such as by molding the member  634  around isotope portion  640 , or otherwise encapsulating the portion  640  within the member  634 . In  FIG. 3A , the isotope portion  640  is disposed a predetermined distance D from the distal end of the sleeve  610  when member  634  is fully inserted into lumen  618  of sleeve  610 . Alternatively, the portion  640  may be joined to a distal end of the member  634 , or in yet another embodiment the isotope portion may be a separate piece that is pushed by member  634  to a desired distance D from the distal end of the sleeve  610 . In yet another embodiment, the rod  634  may be eliminated, and the isotope may be attached to or otherwise disposed within the sleeve  610 , such as being fixed within the hollow sleeve  610  at a predetermined distance from the end of sleeve  610 . 
     The isotope portion  640  may contribute to the stiffness of the distal portion of the member  634 . In one embodiment, the member  634  extends proximally from the portion  640  a distance at least 10 times the axial length of the portion  640 , and the member  634  has a proximal portion extending intermediate the plunger  632  and the isotope portion  640 , which proximal portion is more flexible than the distal portion of the member  634  associated with and encapsulating the isotope portion  640 . Accordingly, in those cases where the portion  640  is a relatively short, stiff, relatively stiff component, the relatively more flexible proximal portion of the introducer member  634  permits the portion  640  to be advanced along a non-linear path to a desire location. 
     When the sleeve  610  is inserted into a biopsy device, such as a biopsy needle, the position of the isotope portion  640  relative to a feature of the biopsy needle, such as a side tissue receiving aperture, may be established based on various dimensions, such as for instance the length of the biopsy needle and the distance D. The isotope may be positioned in the distal portion of the sleeve  610  so that the isotope is aligned with the side tissue receiving opening (in either a target set sleeve or the biopsy needle) when the sleeve  610  is fully advanced within the biopsy device. Using PET, PEM, BSGI, or other suitable nuclear imaging methods, the position of the isotope (and so the side tissue receiving opening) can be confirmed with respect to the lesion of interest. 
     If desired, a kit of introducers may be provided, wherein at least some of the introducers  600  have a different characteristic dimension D and/or at least some of the introducers have sleeves  610  and/or introducer members with different lengths. A kit may also be provided with one or more sleeves  610 , and a plurality of members  634 , each member  634  insertable in at least one sleeve, where one or more of the members  634  have the isotope portion  640  disposed at a different positions along the length of the member  634 . The members  634  and isotope portions  640  may be disposable or reusable. The distance D can be provided such that the isotope is aligned with the side tissue receiving opening in either a biopsy device and/or a target sleeve. 
     In one alternative, the sleeve  610  may also include a side aperture. The member  634  may be inserted into sleeve  610 , to position isotope portion  640  for imaging. The member  634  may then be removed, and one or more biopsy markers may be directed through sleeve to be deployed through the side opening in the sleeve. The biopsy markers may be directed through the sleeve alone, or the markers may delivered through the sleeve with a tubular marker applier. 
     In another embodiment, the sleeve  610  may have a side opening, and the sleeve may be size to receive a biopsy needle such that a side tissue opening of the biopsy needle is aligned with the side opening of the sleeve  610 . After the isotope portion  640  has been imaged with the side opening of the sleeve  610  to confirm the side opening is in a desired location, the member  634  may be removed from the sleeve  610 , and the biopsy needle may be advanced into the sleeve  610 . A cutter may be advanced through the biopsy needle to cut tissue received through the aligned side openings in the sleeve and biopsy needle. The biopsy needle may then be removed, and one or ore markers may delivered through the sleeve. Alternatively, the biopsy needle may remain in place in the sleeve, the cutter may be retracted, and the markers may be delivered through the biopsy needle to the aligned side openings in the sleeve  610  and the biopsy needle. 
     In another embodiment, the isotope may be positionable at a plurality of predetermined locations along the length of the sleeve  610 . For instance, the member  634  could include external ribs or ridges spaced along the length of the member  634 . As the member  634  is advanced or withdrawn from sleeve  610 , the ribs or ridges, when aligned with the proximal end  612  of the sleeve, would correspond to different predetermined distances D. Alternatively, the member  634  may have indicia, such as color coded lines, numerical indicators, or lines of various configuration and/or width, and/or other indicators along the length of the member  634  to indicate predetermined positions to which member  634  may be inserted or withdrawn within the sleeve  610  to provide different distances D. 
     For instance, in  FIG. 3A  two indicia are shown in the form of a relatively thin line  636 A and a relatively thick line  636 B extending around the member  634 . As the member  634  is advanced or withdrawn from sleeve  610 , the position of each indicia  636 A/ 636 B at the end  612  of the sleeve  610  correspond to two different predetermined distances D of the isotope  640  with respect to tip  614 . 
       FIG. 4  illustrates an isotope introducer device  700  comprising an isotope introducer comprising a grip  710  and an elongate member  720  having an isotope portion operatively associated with a distal end of the member  720 . The isotope portion  740  may be joined to the distal end of member  720  using any suitable joining method, including by adhesive bonding, molding, or with a fastener. Alternatively, the portion  740  may be spaced from the distal end of member  720  by a predetermined distance. The member  720  can comprise a relatively flexible rod or tube formed of a medical grade, biocompatible plastic. The introducer in  FIG. 4  provides a one piece device for introducing an imageable isotope to a desired location with in a biopsy device, without requiring a plunger. 
     As yet another variation, an introducer device may include kit including one or more flexible members  720 , of the type shown in  FIG. 4 , and a plurality of tips that can be releasably joined to a distal portion of the member  720 . The kit may include tips of various lengths, diameters, and/or isotope compositions. In yet another embodiment, the isotope may be provided as a sticker or decal which may be affixed to a portion of the flexible member  720 . 
       FIG. 5  illustrates a generalized biopsy device  1000  comprising a housing  1100 , a biopsy needle  1200  extending distally from the housing, and a tissue sample container  1400  disposed at a proximal end of the housing  1   100 . The biopsy needle  1200  is shown having a side tissue receiving aperture  1216  and a distal piercing tip. An isotope introducer, such as one of the introducer device having one or more of the components shown in  FIGS. 1-4  is shown inserted into the proximal end of the biopsy device  1000 , such as a proximal opening in the tissue sample compartment  1400  communicating with a hollow cutter of the biopsy device. 
     In  FIG. 5 , the introducer is provided with sufficient length to extend substantially the full length of the biopsy device  1000 , from a plunger  1502  disposed proximal of the compartment  1400 , to a distal portion of the introducer labeled  1530 , shown aligned with and visible through the side tissue receiving opening in  FIG. 5 . The distal portion  1530  may carry or enclose an isotope portion, or alternatively the distal portion  1530  may be the isotope portion. 
     In those embodiments where the biopsy device includes a hollow internal cutter which translates and rotates within the biopsy needle  1200 , the isotope introducer and isotope portion may be sized and shaped to pass through the hollow internal cutter. The biopsy device may include a proximal opening communicating with hollow lumen of the internal cutter. The cutter may be advanced distally to close the side opening in the needle, such that the distal portion of the cutter is disposed in the distal portion of the needle  1200 . 
     The isotope portion can then be advanced through the hollow cutter such that the isotope is aligned with the side opening in the needle, but spaced from the side opening in the needle by the cutter. Such an arrangement has the advantage that the cutter prevents direct contact between the isotope portion and the tissue adjacent the side opening in the biopsy needle.  FIG. 5A  illustrates a hollow cutter  1290  having an open distal cutting edge  1292  advanced distally within biopsy needle  1200  beyond the distal end of side opening  1276 , so that the upper side wall of the cutter closes the side opening  1276 .  FIG. 5A  also illustrates the isotope portion  1530  advanced into the hollow cutter and aligned within the cutter with the side opening  1276 . Once the isotope is imaged to confirm the location of the side opening  1276 , the isotope may be withdrawn proximally through the cutter, the cutter may be retracted proximally to open the side opening  1276 , tissue may be drawn (e.g. by vacuum) into the opening  1276 , and the cutter may be advanced distally to sever the tissue with cutting edge  1292 . Alternatively, the cutter may be retracted proximally of the biopsy needle side opening, and the isotope may be advanced through the biopsy needle. And substantially aligned with the side tissue receiving opening in the biopsy needle  1200 . 
     The isotope may be positioned in the biopsy needle  1200  prior to the insertion of the needle  1200  into the breast. Generally, it is desirable to have the side tissue opening  1276  closed or at least substantially closed when the needle  1200  is inserted in the breast. The opening  1276  may be closed by advancing the cutter to close the opening  1276 , or alternatively, the isotope portion and introducer member may be advanced through the cutter to close off the opening  1276  (where the isotope portion and introducer member are sized and shaped to fit down the inside of the hollow inner cutter), or the hollow internal cutter may be retracted, and the isotope portion and introducer can be advanced to close off the opening  1276 . For instance, in  FIG. 5 , a distal portion  1530  of the isotope introducer is shown closing off the opening  1276 . The needle  1200  with isotope disposed within the needle can be imaged, such as by using PET or BSGI. Then, the isotope and introducer can be removed from the needle  1200 , and the inner hollow cutter can be advanced to sever tissue received in the opening  1276 . 
     In some variations, a movable sleeve or other component is provided about needle  1200 , permitting at least a portion the isotope rod to be covered, such as to prevent the rod from touching tissue through the transverse opening. Alternatively, a cutter within the needle may provide at least some degree of cover for the isotope rod, as disclosed above. A member may be used to introduce (e.g. by carrying or pushing) the isotope, with the member configured to fit within the inner diameter of a hollow tubular cutter disposed within the outer needle. The cutter may be advanced distally (e.g., to “close off” the transverse opening) as the needle is inserted into tissue, and the cutter may be retracted at least partially to “reveal” the isotope rod when the needle is disposed in tissue. 
       FIG. 6A  and  FIG. 6B  show a modification that may be provided in a biopsy needle to provide imaging of a tissue receiving opening under PET and/or BSGI.  FIG. 6A  is a top view of a needle  1400 , and  FIG. 6B  is a schematic cross-section taken along lines  6 - 6  in  FIG. 6A . 
     The biopsy needle  1400  of  FIGS. 6A and 6B  has a tissue piercing closed tip  1423 , a side (transverse) opening  1416 , and a perforated vacuum wall  1434  disposed below the opening  1416 . Vacuum wall  1434  has a plurality of openings  1436  there through for communicating vacuum provided through a vacuum passageway  1438 . The vacuum passageway  1438  is disposed below an inner hollow cutter  1600 . Cutter  1600  has an open distal cutting end  1610 , and cutter  1600  is translatable and rotatable within a cutter lumen of needle  1400 . 
     As shown in the Figures, an isotope imageable under PET and/or BSGI may be disposed on the vacuum wall  1434 . Accordingly, the opening  1416  will be relatively more visable under PET and/or BSGI. While the wall  1434  is shown as extending only part of the length of the needle in this example, other variations may have a wall extending the full length of the needle. 
     For instance, the wall  1434  may be coated or impregnated with an isotope. Accordingly, when the wall is “revealed” through the transverse opening of the needle, such as when cutter  1600  is retracted proximally, the wall may be seen via PEM and/or BSGI imaging. Being on or in the wall, within the needle, may prevent the isotope from coming into direct contact with tissue (e.g., tissue that is not being severed by the cutter). In some applications, the isotope may be imageable via PEM and/or BSGI, even with the cutter translated distally (e.g., the wall can be “seen” through the cutter using the imaging technique). 
       FIG. 7  illustrates a biopsy device  1600  comprising a biopsy needle  1800  having a distal piercing tip  1810  and a side opening  1800 . In the embodiment of  FIG. 7 , an isotope visible under PEM and/or BSGI is associated with at least a portion of the perimeter of the opening  1816 . In  FIG. 7 , the isotope is shown in the form of a decal  1840  that substantially surrounds the opening  1816 , to provide imaging of the perimeter of the opening  1816  under PET and/or BSGI. 
     The decal comprising the isotope may be applied to the needle just before the biopsy procedure, as opposed to when the needle is manufactured. After the biopsy procedure is complete, the sticker may be removed from the needle and disposed of properly. The decal  1840  may comprise a first outer layer, such as a coating or film layer substantially impervious to moisture, and a second inner layer comprising the isotope used in imaging. The outer layer can be employed to prevent contact of the isotope with the tissue. Alternatively, the perimeter of the side opening may be impregnated with the isotope, or the isotope may be provided as a coating about the perimeter of the opening. 
     While the isotope sticker of the present example is shown in  FIG. 7  as extending about the full perimeter of the transverse opening, it will be appreciated an isotope sticker (or other type of isotope marking) need not extend about the full perimeter of a transverse opening. For instance, in some versions, only the distal and proximal edges are marked. In any case, it will be appreciated that the isotope sticker of the present example may make the transverse opening of the probe needle stand out under PEM and/or BSGI imaging, which may facilitate real time targeting and/or for confirmation of proper needle location as described above. 
       FIG. 8  depicts a perspective view of an isotope introducer device  2000  comprising a grip  2020  and an elongate member  2010  extending distally from the grip. The elongate member may be a flexible rod or tube, or alternatively, the elongate member  2010  may be in the form of a relatively rigid rod or tube. An isotope portion  2040  may be disposed on an outer surface of the member  2010 , such as in a predetermined spaced relation from the distal end  2012  of member  2010 . The isotope portion  2040  may be in the form of a releasable decal or coating applied to the member  2010 . After the biopsy procedure is complete, the sticker may be removed from the member  2010  and disposed of properly. 
     In one embodiment, a kit may be provided having one or more introducer devices  2000 . The devices  2000  can be provided with elongate members having different lengths and/or isotope portions disposed at different positions relative to the distal ends of the devices. The isotope carrying decals may be provided in the kit, or separately, such that the position of the isotope on the elongate member can be selected at the time of use. The decals can be provided in different lengths and/or widths to accommodate different sizes of isotope introducers and/or biopsy devices. 
     While certain specific isotopes have been mentioned herein, it will be appreciated that any other suitable isotope may be used, as well as any suitable combinations of isotopes. Such alternative isotopes may provide emission of positrons, gamma radiation, or any other suitable type of emission or radiation. Furthermore, while PEM and BSGI are described in many of the examples herein as exemplary imaging modalities, it will be appreciated that any other suitable imaging modalities may be used, including combinations thereof. In other words, devices disclosed herein may be used in a variety of settings, including those in which some imaging modality or modalities other than PEM and BSGI are used, including but not limited to MRI, x-ray, modalities detecting radiation emitted from a patient, etc. Suitable alternative imaging modalities will be apparent to those of ordinary skill in the art in view of the teachings herein. To the extent that alternative imaging modalities are used, the devices described herein may be used with such alternative imaging modalities with or without further modifications to the devices described herein. Suitable modifications to the devices described herein, for use with PEM or BSGI imaging or any other imaging modalities, will be apparent to those of ordinary skill in the art in view of the teachings herein. 
     Embodiments of the present invention may have application in conventional endoscopic and open surgical instrumentation as well as application in robotic-assisted surgery. 
     Embodiments of the devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. Embodiments may, in either or both cases, be reconditioned for reuse after at least one use. Reconditioning may include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, embodiments of the device may be disassembled, and any number of the particular pieces or parts of the device may be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, embodiments of the device may be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device may utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application. 
     By way of example only, embodiments described herein may be processed before surgery. First, a new or used instrument may be obtained and if necessary cleaned. The instrument may then be sterilized. In one sterilization technique, the instrument is placed in a closed an sealed container, such as a plastic or TYVEK bag. The container and instrument may then be placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation may kill bacteria on the instrument and in the container. The sterilized instrument may then be stored in the sterile container. The sealed container may keep the instrument sterile until it is opened in a medical facility. A device may also be sterilized using any other technique known in the art, including but not limited to beta or gamma radiation, ethylene oxide, or steam. 
     Having shown and described various embodiments of the present invention, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present invention. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, embodiments, geometries, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present invention should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings.