Abstract:
A sterile needle guide for use during a biopsy procedure includes a planar plate having at least one tubular needle guide extending there through. Needle guide may be manufactured from a kit having plurality of guide tubes each paired with a drill bit. In practice, a drill bit and guide tube are coupled to a drilling machine and positioned relative to a planar blank at a location derived from previously recorded or real-time imaging data. Drilling through the plate causes the guide tube to extend through the plate and become thermally fused therewith. In one embodiment, a guide tube includes multiple needle guide passages enabling multiple, clustered insertion points in a single area from a single guide tube.

Description:
BACKGROUND OF THE DISCLOSURE 
       [0001]    Prostate cancer is the second leading cause of cancer death in the U.S. Over 225,000 cases of cancer were diagnosed in 2014 with almost 30,000 deaths. Prostate cancer is treatable, if properly diagnosed. The initial screen to identify men with prostate cancer is the level of prostate-specific antigen PSA in blood. These men are often referred for a core biopsy in which samples of the prostate are excised and evaluated by a pathologist to determine if cancerous cells are present. There is no information in a PSA blood test to determine where cancerous tissue might be found in the prostate. A 12-core sampling distributed over the prostate has become the accepted method to determine if cancer is present. The procedure is typically conducted using a trans-rectal ultrasound to visualize the needle location, and the needle is typically inserted through the lining of the rectum to reach the prostate. The trans-rectal ultrasound-guided procedure requires a large number of needle insertions, requires high doses of antibiotic prophylaxis, does not make the suspicious region easily visible, and provides no means of recording sample locations for future reference. 
         [0002]    Accordingly, need exists for reducing the number of needle insertions in a prostate biopsy procedure and the need for antibiotics by avoiding accessing the prostate through the rectum. 
         [0003]    A further need exists for a technique which can provide a precise recording of the needle tip location during a biopsy. 
         [0004]    An even further need exists for a patient-specific disposable tool for directing needle entry during a medical procedure, such as an MRI-guided prostate biopsy. 
       SUMMARY OF THE DISCLOSURE 
       [0005]    Disclosed is a customizable needle guide for directing needle entry during a medical procedure, such as an MRI-guided prostate biopsy. In embodiments, the needle guide comprises a plate with one or more tubes inserted into the plate at locations chosen based on patient position and MR images during a biopsy procedure. 
         [0006]    Also disclosed is a method for making a patient-specific disposable tool for directing needle entry during a medical procedure such as an MRI-guided prostate biopsy. More specifically, disclosed is a method for making a needle guide to guide the needle while the patient remains in the MRI. The target locations can be identified in the reference frame of the scanner using initial images and pre-operative multi-parameter MRI, and trajectories can be selected. The needle guide would then be produced and used to complete the biopsy. The needle guide may be created by a method in which a hole is drilled in a plastic plate by friction and a guide tube is inserted and welded in place by friction welding. Fabrication of the needle guide is based on a rapid, precision machine for creating the guide from a sterile kit. 
         [0007]    According to one aspect of the disclosure, a sterile needle guide for use during a biopsy procedure comprises a planar plate having at least one tubular needle guide extending there through. 
         [0008]    According to another aspect of the disclosure, a kit for manufacturing a needle guide under sterile conditions comprises a plurality of guide tubes each having a drill bit paired therewith. In one embodiment, the kit may optionally further comprise a planar blank into which the guide tubes are embedded during the process. 
         [0009]    According to yet another aspect of the disclosure, a system comprises in combination a cylindrical guide tube defining at least one needle guide passage extending therethrough, a drill bit coupled to the guide tube at a first end thereof, and an adapter cap for coupling one of the drill bit and guide tube to a source of motion. 
         [0010]    According to still another aspect of the disclosure, a sterile needle guide for use during a biopsy procedure comprises a cylindrical guide tube body defining a plurality of needle guide passages extending therethrough and having a first end defined for coupling to a drill bit and a second end defined for coupling with an adapter. 
         [0011]    According to yet another aspect of the disclosure, A kit for preparing a needle guide for biopsy procedures comprises: a cylindrical guide tube defining an interior needle guide passage extending therethrough, a drill bit coupled to the guide tube at a first end thereof, a planar plate formed of a material having a lower melting point than the drill bit; and an encapsulating structure defining a selectively accessible interior space in which the guide tube and planar plate are disposed. In one embodiment, the encapsulating structure is defined by a wall which is at least partially movable relative to another section of the encapsulating structure and which allows the guide tube to be re-positioned along three axes relative to the planar plate while remaining within the interior space of the encapsulating structure. 
     
    
     
       DESCRIPTION THE DRAWINGS 
         [0012]      FIG. 1  illustrates conceptually a guide for prostate biopsy in the bore of an MRI scanner; 
           [0013]      FIG. 2  illustrates conceptually a needle guide template in accordance with the present disclosure; 
           [0014]      FIG. 3  illustrates conceptually an apparatus for automatically moving a drill relative to a plate in accordance with the present disclosure; 
           [0015]      FIG. 4  illustrates conceptually a side, cross-sectional view of kit and drill in accordance with the present disclosure; 
           [0016]      FIGS. 5A-F  illustrate conceptually a fabrication process used to generate a custom needle guide in accordance with the present disclosure; 
           [0017]      FIGS. 6A-C  illustrate conceptually interfaces between a non-sterile drill and sterile parts of the kit in accordance with the present disclosure in accordance with the present disclosure; 
           [0018]      FIGS. 7A-C  illustrate conceptually drill bit configurations in accordance with the present disclosure; 
           [0019]      FIGS. 8A-B  illustrate conceptually drill bit configurations in accordance with the present disclosure; 
           [0020]      FIGS. 9A-D  illustrate conceptually exploded, perspective views of drill bit, guide tube and/or adapter combinations in accordance with the present disclosure; 
           [0021]      FIGS. 10A-B  illustrate conceptually side and perspective views of a cylindrical needle guide in accordance with the present disclosure; 
           [0022]      FIG. 11A  illustrates conceptually an exploded, perspective views of a drill bit, guide tube and adapter combinations in accordance with the present disclosure; 
           [0023]      FIG. 11B  illustrates conceptually an exploded, perspective views of a kit in accordance with the present disclosure; 
           [0024]      FIG. 11C  illustrates conceptually a kit disposed inside an outer sterile package in accordance with the present disclosure; 
           [0025]      FIGS. 12A-F  illustrate conceptually a sterile fabrication process used to generate a custom needle guide from the a kit in accordance with the present disclosure; 
           [0026]      FIGS. 13A-B  illustrate conceptually exploded and side views of drill bit, guide tube and/or adapter CAP combinations in accordance with the present disclosure; 
           [0027]      FIGS. 14A-D  illustrate conceptually perspective, side, cut-away, and lateral views, respectively, of a kit in accordance with the present disclosure; 
           [0028]      FIGS. 15A-B  are views of another kit in accordance with the present disclosure; 
           [0029]      FIG. 16  is a top view of the kit of  FIGS. 14 and 15 ; 
           [0030]      FIGS. 17  A-B illustrate conceptually the relationship of the kit of  FIGS. 14 and 15  relative to a fabrication machine in accordance with the present disclosure, 
           [0031]      FIGS. 18A-H  illustrate conceptually the process sequence by which a fabrication machine is used to generate a custom needle guide utilizing kit of  FIGS. 14 and 15 ; 
           [0032]      FIG. 19  is a perspective view of another kit in accordance with the present disclosure;; and 
           [0033]      FIGS. 20A-F  illustrate conceptually the process sequence by which a fabrication machine is used to generate a custom needle guide utilizing kit of  FIG. 19 . 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    According to one aspect of the disclosure, a method for quickly creating a customized sterile needle guide based on an MRI scan is disclosed. The customization procedure is performed while the patient is in the scanner, only a few minutes after the intra-operative scan that is used to design the template. There is not time to sterilize the parts after fabrication, so the needle guide template is produced under sterile conditions. 
         [0035]      FIG. 1  illustrates conceptually the process for an MRI-guided trans-perineal approach using a fixed patient-specific template to guide the needle to targets. In the disclosed method, the patient  101  is placed in the MRI scanner  102  with his feet fixed in stirrups  103 . A needle guide  104  created during the procedure after an initial scan of the patient is used to guide the biopsy needle  105  that is attached to the needle activator  106 . The needle guide is constructed to permit the needle  105  to be inserted into a chosen location within the prostate  107 . By accurately targeting MRI-visible regions suspected of containing cancer, the disclosed apparatus and technique will improve the ability to find life-threatening tumors and reduce the chance of unnecessarily treating low-risk cases compared to current methods. 
         [0036]      FIG. 2  illustrates conceptually a needle guide in accordance with the present disclosure. The needle guide comprises a flat plate  108  with one or more guide tubes  109  embedded therein. A biopsy needle  105  is inserted through guide tube  109  and into the perineum. The guide tubes may be color coded to match regions highlighted on a computer screen image. The guide tubes  109  are joined to the flat plate  108  at positions that correspond to the axis of the needle, when the guide is mounted in the scanner. In an illustrative embodiment, both the flat plate  108  and guide tubes  109  are made from a substantially rigid material such as natural or synthetic resins which can be manipulated for rapid manufacturer of the needle guide in accordance with the methods disclosed herein. 
         [0037]    Referring to  FIG. 3 , a machine  200  for manufacturing a sterile needle guide during a medical procedure comprises a drill  201  and a system of automated actuators  202 - 204  that permit motion of the drill  201  relative to a stage  205  along three axes, so the guide tube  109  can be positioned with sufficient range over the plate  108  mounted on the stage and the drill can move along its own axis to create a hole in the plate. The machine  200  and, in particular, automated actuators  202 ,  203  and  204  may be implemented using any number of commercially available server motor actuated components which may be numerically controlled based on data derived from image data taken either prior to or during the medical procedure. 
         [0038]      FIG. 4  illustrates conceptually a side, cross-sectional view of an exemplary implementation of a kit for creating the sterile needle guides. The kit  225  comprises several rigid guide tubes  109 , e.g. cylinders made of thermoplastic, each having a friction-drilling bit  110 , e. g., high-temperature plastic, contained therein and on a sterile tray  206 . A sterile adapter  210  may be included in the kit to provide an interface between the drill motor  201  and a surface  211  on either the friction-drilling bits  110  or guide tubes  109 . The purpose of the sterile adapter is to prevent transfer of contaminants or microorganisms from the drill motor or associated extensions to the bits or guide tubes. The sterile adapter may be attached manually to the drill motor or it may be removed from the kit and attached to the drill motor by automated means. The bits and guides are mated in pairs so that the guide tube cannot spin with respect to the bit, permitting the drill to spin both guide tube and bit when either is held in the adapter. A blank flat plate  108  may optionally be attached to tray  206  or may be provided separately. Guide features  207  align the plate to the stage  205  in the automated template-making machine  200 . 
         [0039]      FIGS. 5A-F  illustrate conceptually the process sequence by which the machine  200  is used to generate a custom guide from the disclosed kit. As noted, fabrication of the needle guide utilizes a rapid, precision machine for creating the guide from a sterile kit. In an illustrative sequence of images in  FIGS. 5A-F , assume that the plate moves in two axes normal to the drill axis, though the same process can be accomplished by moving the motor itself. In  FIG. 5A , the machine moves the plate such that one of the bit/guide tube pairs is directly under the drill motor with a sterile adapter. The drill moves down and attaches to the bit, as illustrated in  FIG. 5B . This could be by mechanical threading or use of an electromagnetic collet. The drill is raised and the plate is moved so that the drill is directly over the point on the plate where the guide tube is to be installed, as illustrated in  FIG. 5C . The drill spins to a high speed and descends so the bit tip contacts the template and begins to melt the plate locally by friction heating as illustrated in  FIG. 5D . The bit continues to descend until the guide tube flange is against the plate top surface, as illustrated in  FIG. 5E . The drill stops spinning the guide tube, allowing it to stop by friction, heating the surfaces of the guide tube and plate so they melt and fuse together. The drill releases the bit, as illustrated in  FIG. 5F , allowing the bit to drop out of the guide tube. Note that the plate and guide tubes are never contacted by any part of the unsterile machine  200  or drill motor  201 . 
         [0040]      FIGS. 6A-C  illustrate conceptually methods for manipulating sterile components, e.g., guide tubes and drill bits, with a non-sterile drill without contaminating the sterile components by employing a sterile adapter. Sterile adapters  301  or  302  each have at least a first exterior surface,  301   a  or  302   a , respectively, that frictionally engages the drill  201  and may become contaminated upon contacting the drill as well as a second interior surface,  301   b  or  302   b , respectively, that remains sterile and are used to contact the sterile components of the kit. Sterile adapter  301  may be implemented as a single integrally formed piece of semi-flexible material having an exterior surface with a profile which complements the features, e.g. a cavity or interior profile, of the drill bit or collet into which the sterile adapter is to be inserted and frictionally retained therein, as illustrated in  FIGS. 6A-B . In embodiments, one end of the sterile adapter may include, features, e.g. a cavity or interior profile, which are designed to receive and frictionally retain an end of guide tubes  109  therein while the adapter  301  itself is attached to the drill  201 . In one embodiment, as illustrated in  FIG. 6C , an adapter  302  may be pre-fitted over a component e.g., guide tube  109  and bit  110 , and attached to drill  201  with a non-sterile collet  303 . The sterile adapters disclosed herein may be attached manually to a drill motor or may be removed from the sterile kit and attached to the drill motor by automated means. As noted previously, in embodiments, the sterile kit may include an adapter pre-fitted onto each of the guide to and drillbit combinations within the kit. 
         [0041]    According to another aspect of the disclosure, a number of different drill bit and adapter configurations may be utilized to frictionally weld the guide tubes  109  to the plate  108 . Referring to  FIGS. 7A-C  and  8 A-B, a number of different drill bit configurations are illustrated.  FIGS. 7A-C  illustrate several generally conical shaped drill bit tips suitable for use with the disclosed embodiments.  FIG. 7A  illustrates the drill bit tip  401  having a generally conical shape with uniformly tapered sides.  FIG. 7B  illustrates the drill bit tip  402  having a generally conical shape with sides that taper non-uniformly to have an at least partially curved convex exterior profile.  FIG. 5 c    illustrates a drill bit tip  403  having a generally conical shape with sides that taper non-uniformly to have an at least partially curved concave exterior profile. These generally conical shaped bits push material out of the way, penetrating the surface of plate  108  and gradually melting a larger diameter therein. 
         [0042]      FIGS. 8A-B  illustrate several generally cup shaped drill bit tips suitable for use with the disclosed embodiments.  FIG. 8A  illustrates a drill bit tip  404  having a generally cup shape characterized by a uniform diameter cavity  405 , illustrated in phantom, extending at least partially through the interior thereof.  FIG. 8B  illustrates a drill bit tip  406  having a generally cup shape characterized by a tapered diameter cavity  407 , illustrated in phantom, extending at least partially through the interior thereof. During the welding process, the generally cup-shaped drill bits  404  and  406  melt a ring along their respective outer diameters and capture the material excised from plate  108  and retain such material as a plug inside their respective interior cavities. 
         [0043]    According to another aspect of the disclosure, a number of adapter and/or guide tube and drill bit configurations may be used for joining drill bits to guide tubes and for transmitting torque from a drill to a drill bit and/or guide tube without contact between the drill head and the drill bit and/or guide tube. Referring to  FIG. 9A , an exploded perspective view of a configuration is illustrated in which an adapter  410  is receivable within a guide tube  411  and a drill bit  412  to allow transmission of torque from the adapter to the drill bit. In  FIG. 9A , adapter  410  comprises a cylindrical drive knob  410 A having a rod  410 B extending outward therefrom. In the illustrative embodiment, rod  410 B has a rectangular cross-sectional profile. Guide tube  411  comprises a generally cylindrical body  411 B defining a central passage or lumen  411 C extending therethrough. In the illustrative embodiment, passage  411 C has a cross-sectional profile which mimics that of rod  410 B but is sized to allow insertion of rod  410 B therein. Guide tube  411  further comprises a flanged head  411 A at one end thereof. Drill bit  412  is shape similar to drill bit  401  of  FIG. 7A  but has a cavity  412 A extending at least partially into the interior thereof. In the illustrative embodiment, cavity  412 A has a cross-sectional profile which mimics that of rod  410 B but is sized to allow insertion of rod  4100 B therein. Drill bit  412  is driven by attachment to rod  410 B connected to drive knob  410 A. In the use, the adapter  410 , guide tube  411  and drill bit  412  may be preconfigured together, as similarly illustrated in  FIGS. 3 and 4  with rod  410 B disposed within passage  411 C and cavity  412 A. A drill chuck may grab drive knob  410 A to pick up the assembly and position drill bit  412  over plate  108  to perform the drilling/welding procedure. After the guide  411  is welded in place, the drill chuck pulls the drive knob  410 A in a retrograde direction, removing the rod  410 B and allowing the bit  412  to fall away. 
         [0044]    Referring to  FIG. 9B , an exploded perspective view of a system configuration is illustrated in which guide tube  413  comprises cylindrical body  413 B that extends above flange  413 A and a passage  413 C having a circular cross-sectional profile that opens at one end thereof into a rectangular shaped cavity  413 D which is sized to receive stub extension  414 A of drill bit  414  therein. The portion of guide tube  413 B that extends above flange  413 A is receivable within an adapter not shown, substantially similar to adapter  301  and attached to a drill, so that torque is transmitted from the adapter to the drill bit. In the use, the guide tube  413  and drill bit  414  may be preconfigured together. A drill fitted with the adapter picks up the assembly and positions drill bit  414  over plate  108  to perform the drilling/welding procedure. After the guide  413  is welded in place, the drill with adapter releases guide tube  413 , leaving bit  414  to be removed manually. 
         [0045]    Referring to  FIG. 9C , an exploded perspective view of a system configuration is illustrated in which stub  415 C of adapter  415  and stub  414 A of a drill bit  414  are receivable within a guide tube  416  to allow transmission of torque from the adapter to the drill bit. Adapter  415  is implemented substantially as previously described but without a rod e.g.,  410 B extending outwardly therefrom. In the use, the adapter  415 , guide tube  416  and drill bit  414  may be preconfigured together. A drill chuck grabs drive knob  415 A to pick up the assembly and position drill bit  414  over plate  108  to perform the drilling/welding procedure. After the guide  416  is welded in place, the drill chuck pulls the drive knob  415 A in a retrograde direction, leaving the bit  414  to be removed manually. 
         [0046]    In  FIG. 9D , adapter  418  comprises a cylindrical drive knob  418 A having a rectangular stub extension  418 B extending outwardly therefrom and a rod  418 C extending outward from stub extension  418 B. In the illustrative embodiment, rod  418 C has a circular cross-sectional profile. Guide tube  419  comprises a generally cylindrical body  419 B defining a central passage or lumen  419 C extending therethrough. In the illustrative embodiment, passage  419 C has a circular cross-sectional profile which mimics that of rod  418 C but is sized to allow insertion of rod  418 C therein. Guide tube  419  further comprises a flanged head  419 A at one end thereof. Drill bit  420  may be implemented similar as described previously herein. Passage  419 C opens into a rectangular shaped cavities  419 D and  419 E which are sized to receive stub extension  420 A of drill bit  420  and stub extension  418 B of adapter  418 , respectively therein. Drill bit  420  is held into the guide tube  419  by rod  418 B which fits into circular cavity  420 B in the drill bit. Drill bit  420  is driven by attachment to guide  419 . In the use, the adapter  418 , guide tube  419 , and drill bit  430  may be preconfigured together, with rod  418 C disposed within passages  419 C and  420 B. A drill chuck grabs drive knob  418 A to pick up the assembly and position drill bit  420  over plate  108  to perform the drilling/welding procedure. After the guide  419  is welded in place, the drill chuck pulls the drive knob  418 A in a retrograde direction, removing the rod  418 C and allowing the bit  420  to fall away. 
         [0047]    According to another aspect of the disclosure, a guide tube includes multiple guide passages so that a single guide tube provides the option for multiple, clustered insertion points in a single area from a single guide tube. Referring to  FIGS. 10A-B , a guide tube  510  comprises a generally cylindrical body  510 A, having a plurality of sections with different cross-sectional diameters. Guide tube body  510 A further defines a central needle guide passage or lumen  510 B extending therethrough and a plurality of needle guide side passages  510 C surrounding lumen  510 B. In the illustrative embodiment, passages  510 C are evenly spaced about passage  510 B with the respective centers of passages  510 C located on a circle radius measured from the center of passage  510 B. In the illustrative embodiment, passages  510 B-C have a cross-sectional profile which mimics that of rods  511  but is sized to allow insertion of rods  511  therein. Guide tube  510  further comprises a flanged head  511 D at one end thereof defining an abrupt increase in diameter in comparison to the diameter of cylindrical body  510 A. Guide tube  510  may be paired with a drill bit and adapter similar to the adapter/guide tube/drill bit systems described herein for joining drill bits to guide tubes and for transmitting torque from a drill to a drill bit and/or guide tube without contact between the drill head and the drill bit and/or guide tube. 
         [0048]    Referring to  FIG. 11A , an exploded perspective view of a guide tube stack  515  is illustrated as comprising an adapter  514 , guide tube  510 , rods  511  and drill bit  512 . A pair of rods  511  is receivable within any combination of passages  510 B-C of a guide tube  510  and drill bit  512  to allow transmission of torque from the adapter  514  to the drill bit  512 . Drill bit  512  maybe shape similar to drill bit  404  of  FIG. 8A  or drill bit  406  of  FIG. 8B  but has a central passage and at least one off-center passage at least partially extending therethrough and having cross-sectional passage profiles which mimic that of rods  510  but are sized to allow insertion of rods  510  therein. Drill bit  512  is driven by attachment to rods  511  which are, in turn, connected to adapter  514 . In the use, the adapter  514 , guide tube  511  and drill bit  512  may be preconfigured together into guide tube system  515 , as similarly illustrated in  FIG. 11B  with rods  511  disposed within passages  511 B-C and similar corresponding passages of drill bit  512 . A drill chuck may grab adapter  514  to pick up the assembly and position drill bit  512  over plate  108  to perform the drilling/welding procedure. After the guide  510  is welded in place, the drill chuck pulls the adapter  514 , in a retrograde direction, removing the rods  511  and allowing the drill bit  512  to fall away, in a procedure similar to that utilizing the other guide tube and drillbit combinations described herein. 
         [0049]      FIG. 11B  is a conceptual exploded view of a kit  520  comprising a tray  525  to which a plate  522  and a plurality of guide tube stack  515  may be removably secured. In the illustrative embodiment, tray  525  has a generally rectangular shape defining a plurality of interior segmented cavities, one of which defines a plurality of sockets  525 A projecting outward therefrom and into which guide tube systems  515  may be removably received. In embodiments, either adapter cap  514  or drillbit  512  may be received into sockets  525 A. Plate  522 , as illustrated, has a generally rectangular shape with a plurality of clips about the peripheral edges thereof for securing to the perimeter edges of tray  525 . In embodiments, tray  525  may have handle  525 B and handle cover  525 C to assist with handling of kit  520  in a sterile environment. Plate  522 , may have the same construction and function as plate  108  described herein. An optional film  526  may be disposed adjacent to the surface of the plate  522 . Film  522  is used to protect the surface of plate  522  from a non sterile environment. 
         [0050]    In embodiments, any of drill bits  401 - 404 ,  406 ,  412 ,  414 ,  420  or  512  may be formed of Polyether Ether Ketone PEEK plastic, a colourless organic thermoplastic polymer in the polyaryletherketone PAEK family. PEEK plastic is a semicrystalline thermoplastic with excellent mechanical and chemical resistance properties that are retained to high temperatures. PEEK plastic melts at a relatively high temperature 343° C./649.4° F. compared to most other thermoplastics enabling any of drill bits to be formed or processed using injection moulding or extrusion methods. Any of drill bits  401 - 404 ,  406 ,  412 ,  414 ,  420  or  512  may also be formed of aluminum or stainless steel, or any material having a higher melting temperature than the plate  108  and which is magnetic resonance compatible. 
         [0051]    In embodiments, any of adapter  410 ,  415 ,  420  and  514  may be formed of stainless steel or other rigid, sterilizable material. In embodiments, any of guide tubes  411 ,  413 ,  416 ,  419  and  510  may be formed of plastic, including, but not limited to, natural or synthetic resins which are rigid enough to transmit torque from the adapter to the drill bit but which have a lower melting point than the drill bit for fusing with plate  207  during the drilling/welding process. 
         [0052]    Because the environment in the Guide Fabrication Machine (GFM) used to create the needle guide is likely to become contaminated, leading to contamination of the needle guides it produces, a need exists for a mechanism in which the needle guide can be produced without being exposed to an external environment. 
         [0053]    According to another aspect of the disclosure, the needle guide kit  520 , and its needle guide components, are completely enclosed in a sealed sterile cover. Prior to use, e.g., during shipping and storage, the kit  520  is contained inside an outer sterile package  517 , shown in  FIG. 11C . In one embodiment, the package  517  may comprise a vacuum-formed polystyrene tray  517 A in which the kit  520  is disposed and retained with a peel-off top  517 B. The kit  520  may be sterilized using gamma radiation after packaging. 
         [0054]    According to another aspect of the disclosure, the internal components of a needle guide kit are isolated from the outside environment during fabrication. In one embodiment, a needle guide kit  530  may comprise a tray  531  holding substantially the same components as kit  520  described herein but with only a single stack  532 . In addition, a bag  534  is sealingly fixed over the top edge of tray  531  above the surface of plate  522 . In addition, a peel away decal, not shown, similar to decal  557  described elsewhere herein may be disposed over the open end of tray  531  help isolate the plate  552  from the environment exterior to kit  530 . Bag  534  has fixed thereto an interface  536  through which the stack  532  is movably disposed, as illustrated in  FIGS. 12A-B . Interface  536  may comprise, in one embodiment, a rubber seal fixed directly adjacent the exterior surface of bag  534  and a rigid or semirigid holder disposed adjacent the rubber seal, both the rubber seal and holder having apertures to movably retain stack  532  therein. Bag  534  is dimensioned large enough so that interface  536  may be moved in three axes relative to the surface of plate  108  during the fabrication process and may be made from a thin flexible antimicrobial material. As such, bag  534  may be folded upon itself during transport and storage with the interior of kit  530  remaining sterile.  FIGS. 12A-F  illustrate conceptually the sterile fabrication process used to generate a custom needle guide from kit  530 , with  FIGS. 12B, 12D, 12F  included only for comparison purposes to indicate the relative position of interface  536  relative to plate  522  during the process of placing the guide tube. 
         [0055]      FIGS. 12A, 12C, and 12E  depict the process for placing a guide tube at a desired location on a plate using the computer-controlled actuators of a guide fabrication machine. First, the drill head is positioned directly above the stack  532  and then lowered until the drill head is over the cap of stack  532 , as illustrated in  FIG. 12C . Next, an automatic chuck is activated, grabbing the cap and, therefore, the entire stack  532 . The stack  532  is repositioned over the location where the guide tube is to be placed, as illustrated in  FIG. 12E . This motion may be in two dimensions to cover the entire plate as needed, but is shown only along one axis in  FIG. 12  for purposes of explanation. Note that as the drill moves the components of the stack, the flexible sterile barrier created by bag  534  deforms in three dimensions, as needed, to accommodate the motion and thus remains a sealed barrier throughout the production process. Next, the drill spins and lowers the stack. The drill bit heats the plate by friction, creating a hole as it passes through the plate. The drill bit may be made of PEEK, a high-temperature plastic that has a melting point well above that of the plate material (ABS). The interior cavity of the bit captures most of the plastic that is removed from the hole, and the remainder of the displaced plastic forms a rim around the hole. Friction drilling eliminates the formation of small debris particles that are produced in conventional drilling. After the hole is created, the spinning stack  532  continues advancing until the flange of the guide tube reaches the plate  522 . Friction between the flange and the plate melt a thin layer of plastic on each welding the two surfaces together. The entire process, including drilling, welding, and cooling, may take only about 10 seconds. Once the guide tube has been welded into the plate, the drill is retracted. Because the drill chuck is gripping the cap, the cap and pins are pulled from the stack  532 . The drill bit falls below the plate  522  into the tray  531 . 
         [0056]      FIGS. 13A-B  illustrate another embodiment a stack  542  for fabrication of a clean needle guide  540 . The kit from which the needle guide  540  is made includes a plate  544  and one or more stacks  542 , each consisting of a bit  541 , a guide tube  543 , a cap  547 , and pins  548 . The pins  548  are fixed to the cap  547  and pressed into the bit  541  and can transmit torque to the bit  541  and guide tube  543 . 
         [0057]      FIGS. 14A-D  illustrate the construction of a needle guide fabrication kit  550 , according to another aspect of the disclosure, in which the component parts of the kit necessary to construct a needle guide are completely contained inside a barrier, Friction drilling and welding during the needle guide fabrication process are accomplished by working through sealed bushings, allowing holes to be drilled and guide tubes welded into place without transferring contaminants across the barrier. In an illustrative embodiment, needle guide kit  550  comprises a substantially circular shaped base  552  defining a cavity and having an aperture along the perimeter thereof into which plate  544  may be slidably removed. Base  552  is enclosed with a cover  554  the rims of which form labyrinth seals  555 . Allowing for rotational movement of cover  554  upon the application of force to a panel  551  projecting upward from the cover. A tour at  556  is rotationally secured through the labyrinth seals into the top of cover  544 . Turn  556  may be rotated by the application of force to a Tarrant panel  553  projecting upward therefrom. A plurality of stacks  542  are retained within bushings  558  projecting upward from the top surface of turn  556  to allow interaction of caps  547  of each stack with a drill bit chuck or collect. A POA decal  557  may be used to temporarily seal plate  544  within the interior of base  552 , as illustrated. 
         [0058]    The turret  556  is retained in the rotary cove  554 , which is retained by the base  552 , so it is not possible to inadvertently lift either the turret or cover off of the kit, exposing the plate. As the cover  544  rotates, its peripheral edge slides along the top edge of the base  552 . As the turret rotates, its outer edge slides against the cover. As shown in  FIG. 14C , both the cover  554  and turret  556  use labyrinth seals  555  to prevent ingress of contaminants while allowing rotatation thereof. Labyrinth seals are not air-tight, however, they create a tortuous path through which contaminants will not pass readily without substantial force. To seal space from contaminants during the guide fabrication process, all rotating surfaces are sealed. The turret  556  and cover  554  are sealed with a flexible plastic skirt that rotates with the moving part and slides along the fixed part. The caps  547 , which spin and slide for the drilling and friction welding process are sealed with a pair of elastomer rings, e.g., silicone o-rings,  559  which provide a high-reliability air-tight seal. 
         [0059]    A clean environment is maintained during onsite guide manufacturing by inclusion of seals around the base/cover and cover/turret junctions, as well as around the caps where they pass through the turret. Note that the seals shown in  FIG. 15A  only need to maintain a clean barrier during fabrication of the guide and transport into the MRI room. 
         [0060]    The caps  547  are extensions of the drill bits  541  and guide tubes  543  that protrude through seals  559  in the turret  556 . The Guide Fabrication Machine (GFM) can grip the caps and drill just as with the previous design. The caps  547  are situated within a pair of o-ring seals which can allow the cap to rotate and slide while maintaining an air-tight seal. The o-rings may be made of silicone, buna nitrile, or other elastomer. The ring cross section, shown on the bottom of  FIG. 3 , is deformed when the ring is pressed between two surfaces. This is the same type of sliding seal used in many syringes. 
         [0061]      FIG. 16  illustrates conceptually the kinematics of rotary design relative to plate  544 , illustrated in phantom to indicate that it is beneath turret  556  and cover  554 . The two rotating pieces, turret  556  and cover  554 , are equivalent to two virtual links (or line segments). If the links are of equal length (the bit circle crosses the center of the cover) and the sum of the lengths Link 1 +Link 2  is at least the distance from the cover center to the furthest point on the cover, the bits can be positioned over any point on the plate  544 . By rotating the turret  556  and cover  554  independently, any of the bits  541  can be positioned over any point on the plate  544 , allowing placement of up to six guide tubes  543  at desired positions on the plate  544 . This this process requires that the circle containing the bits passes through the center of rotation of the cover, and that the sum of the distances from the cover center-of-rotation to the turret center-of-rotation and the radius of the bit circle are at least as large as the distance from the plate center to the plate corner. 
         [0062]    The xyz traverse in the GFM  600  comprises three robot stages that can move in coordination on, for example, circular paths. To position a drill bit and guide tube at a desired location, the xyz stage(s) push the paddles  553  and  551  with the drill chuck to rotate the turret  556  and rotary cover  554 , as shown in  FIG. 17A-B . In the  FIG. 17A , the drill collet pushes paddle  551  and rotates the cover  554 . In the  FIG. 17B , the drill collet pushes paddle  553  and rotates the turret  556 . 
         [0063]      FIGS. 18A-H  illustrate conceptually the process sequence by which the machine  600  is used to generate a custom needle guide from a kit  550  placing a guide tube  43  at a desired location on plate  544  with drilling and welding accomplished by working through sealed bushings  558 . In an illustrative sequence of images in  FIGS. 18A-H , assume that the cover  554  and turret  556  rotate 360 degrees. All steps are performed by the computer-controlled X, Y and Z actuators  560 ,  562  and  564 , respectively, in the Guide Fabrication Machine (GFM)  600 . 
         [0064]    The kit  550  is shipped inside an outer sterile package  517 . Prior to use, the kit  517  is removed from its packaging, as illustrated in  FIG. 18A . The kit  517  is placed in the GFM  600  as illustrated in  FIG. 18B . The drill is lowered beside the cover paddle  551  and uses the cover paddle to rotationally move the cover  554 , and turret paddle  553  to rotationally move the current  556 , to position the stack  542  over the desired guide location on plate  544  as illustrated in  FIG. 18C . Next, the drill chuck is repositioned over the stack and lowered over the cap  547  thereof. Then, the automatic chuck is activated, grabbing the cap  547 , as illustrated in  FIG. 18D . The drill spins and lowers the bit  541 , as illustrated in  FIG. 18E-F . The drill bit  541  heats the plate  544  by friction, creating a hole as it passes through the plate  544 . After the hole is created, the spinning stack  542  continues advancing until the flange of the guide tube  543  reaches the plate  108 . Friction between the flange and the plate  544  melt a thin layer of plastic on each. Once the guide tube  543  has been welded into the plate  544 , the drill is retracted. Because the chuck is gripping the cap, the cap  547  and pins  548  are pulled from the stack  542  The drill bit  544  falls below the plate into the tray. The foregoing steps are repeated for each guide tube  543  inserted into plate  544 . 
         [0065]    In clinical use, the kit  550  will be contained in a sealed outer package  517 . At the start of the procedure, the technician will open the outer package, remove the kit  550 , and place it in the guide fabrication machine  600 . The barrier prevents contamination of the interior components. Once the custom needle guide has been fabricated, the kit is removed from the machine. The barrier is still intact and the components inside are clean, though the outside of the kit is not clean. The kit is transported to the procedure room. When the radiologist is ready to install the needle guide in the frame and perform the biopsy, the technician removes the adhesive cover  557  from the kit  550 , and the the radiologist, with sterile gloved hands, will remove the custom fabricated needle guide for use. The GFM  600  will typically be located in a room adjacent to the MRI procedure room. The machine will be maintained to be clean but will not be sterile. The primary barrier around the kit and the seals as described help isolate the needle guide components from the time the package is opened until the decal  557  is peeled back for the radiologist to remove the plate  544 . 
         [0066]    The reader will appreciate that the disclosed fabrication process includes a barrier that fully encloses the parts of the needle guide kit, with friction drilling and welding accomplished by working through sealed bushings. 
         [0067]      FIG. 19  illustrates another kit  570  with flexible barriers which allow a custom fabricated needle guide to remain completely isolated from airborne and surface contaminants in the exterior environment until it is removed from the outer package in the procedure room. In one embodiment, a needle guide kit  570  may comprise a tray  571  holding a plate  574  in an interior surface therein. Slidably fixed over lower tray  571  is an upper tray  573  which is slidable in both the X and Y axis using, for example, slidable tracks. Fixed to the top of upper tray  573  is one or more stacks  542  as previously described a flexible barrier  575  is disposed about the tray  571  and upper tray  573  and is sealed to the top of uppercase  573  to allow caps  547  of stacks  542  two protrude there from. Flexible barrier  575  is further sealed about an open end of lower tray  571  to allow for removal of plate  574  following the fabrication process. A peel away decal  577  may be used to cover open end of lower tray  571  prior to completion of the fabrication process. Flexible barrier  575  is dimensioned large enough so that upper tray  573  may be moved in along the X and Y axes relative to the surface of plate  574  during the fabrication process and may be made from a thin flexible antimicrobial material. The stack  542  are disposed in bushings, identical to bushings  558  of kit  550 . The bits  541  are all kept in an upper tray  573  as it is translated translates in two directions. The xyz stage of the GFM  600  grips the caps  547  of stacks  542  using the automated chuck and uses them to move the upper tray  573  until a stack is over the desired location on plate  574 . 
         [0068]      FIGS. 20A-F  depict the process for placing a guide tube at a desired location on a plate  574  using kit  570  which was a guy of simplicity do not show the tracks fixing lower tray  571  two upper tray  573 . All steps are performed by the computer-controlled actuators in the guide fabrication machine  600  in a manner substantially similar to that described with reference to kit  530  and  FIG. 12 . The drill is lowered until is over the cap  547 . Then, the automatic chuck is activated, grabbing the cap and thus the entire stackv  542 . The stack is repositioned over the location where the guide tube  543  is to be placed. This motion is in two dimensions to cover the entire plate  574  as needed, but is shown here in only one axis for purposes of explanation. Note that as the drill moves the components of the stack, the flexible sterile barrier  575  deforms, as needed to accommodate the motion and thus remains a sealed barrier throughout the fabrication process. The drill spins and lowers the stack  542 . The drill bit heats the plate  574  by friction, creating a hole as it passes through the plate. After the hole is created, the spinning stack continues advancing until the flange of the guide tube reaches the plate. Friction between the flange and the plate melt a thin layer of plastic on each. The drill stops, allowing the parts to cool. The guide tube has been friction-welded into the plate. The entire process, including drilling, welding, and cooling, takes about 10 seconds. Once the guide tube has been welded into the plate, the drill is retracted. Because the chuck is gripping the cap, the cap and pins are pulled from the stack. The drill bit falls below the plate into the tray. 
         [0069]    In other embodiments, the disclosed apparatus and techniques can be extended for use in other MRI-guided procedures that require biopsies or treatments for prostate cancer. 
         [0070]    It will be obvious to those recently skilled in the art that modifications to the apparatus and process disclosed here in may occur, including substitution of various component values or nodes of connection, without parting from the true spirit and scope of the disclosure.