Abstract:
Braces to reduce bending of a brachytherapy needle during insertion into a patient, as well as methods of using the needle braces and kits useful therefor.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is directed to the field of brachytherapy equipment. More specifically, the present invention relates to a brachytherapy needle and a brace to help minimize bending of the needle during needle insertion into a patient. 
       BACKGROUND OF THE INVENTION 
       [0002]    Implanting brachytherapy seeds into a patient typically involves loading a number of such seeds, possibly including spacers between successive and either loosely or within a carrier strand, into a brachytherapy implantation needle. The needles are typically formed from a medically-compliant metal, such as stainless steel. The loaded needle typically includes the seeds at one end within the needle and a stylet extending from the seeds out the opposite end of the needle. A grid, or template, providing guide-holes is sometimes positioned against the patient so that the physician may accurately guide the seeds to their proper location in or about the target tissue by inserting the needle through the proper hole in the grid. The grid body, being about one-inch thick, receives and provides some support to the sharpened end of the needle. The physician typically drives the needle into the patient by grasping the needle by its hub at the free end. It is preferable to hold the needle by the hub so as to reduce the exposure of the hands to the radioactivity of the seeds at the far end. However, as the grid body holds the sharp end of the needle and the physician holds the needle by the hub at the opposite end, dermal resistance to being punctured can lead to buckling stresses on the needle, causing the needle to deflect or bow quite noticeably. Once the needle begins to penetrate the through the dermis into the perineum, the buckling problem dissipates as the inner tissue provides much less resistance than the dermis. 
         [0003]    The buckling problem has been more pronounced as the delivery needles get smaller in size. For example, the brachytherapy seeds sold as THINSEED™ (marketed by the General Electric Company through its GE Healthcare business) may be implanted using a 20 gage needle. The buckling problem has been observed in some early procedures using THINSEED. As the needle passageway is typically filled throughout its length by seeds and/or spacers and the stylet, permanent deformation of the needle due to the penetration compression forces applied to it is less likely. Nevertheless, physicians report that the bowing of the needle can be a distraction in performing the operation. Physicians will typically hold the needle body with one hand as the other pushes on the needle hub to drive the needle into the patient. Such a manual technique increases physician exposure to the activity of the loaded needles. While thicker needles could be employed, thinner needles are desirable for the lower insult caused to the patient by the smaller tissue displacement as the needle passes and the thinner seeds remain implanted. 
         [0004]    There is therefore a need for a device that will limit the deflection of a brachytherapy needle during penetration. The device should desirably allows the physician to maintain some stand-off from the seeds within the needle so as to help minimize extremity exposure to the activity of the brachytherapy seeds. 
       SUMMARY OF THE INVENTION 
       [0005]    In view of the needs of the prior art, the present invention provides a brachytherapy needle with a brace which reduces bending of the needle as the needle is inserted into a patient. 
         [0006]    The present invention also provides a kit for brachytherapy device including at least one brachytherapy needle and a brace for minimizing the bending of the needle as it is inserted into a patient during a brachytherapy implantation procedure. 
         [0007]    The present invention also reduces extremity exposure while providing long axis rigidity to the needle to reduce bowing. 
         [0008]    In addition to reducing bowing the needle assist can be used as a guide for steering the needle during the penetration process for correct three dimensional placement of the seeds being implanted. This is commonly done by twisting the luer fitting of the needle and repetitively inserting and withdrawing the needle until the desired location is reached. This is also done by guiding the needle by hand, again adding to extremity exposure for the physician. 
         [0009]    In addition to eliminating bowing, aiding guidance, and reducing exposure the needle assist can be used to lock the needle stylet to the luer fitting to ensure the materials within the needle are secured during insertion to the patient. This is done by creating a removable resistive material between the needle stylet and the needle luer fitting. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  depicts a first brace of the present invention for a brachytherapy needle. 
           [0011]      FIG. 2  depicts the brace of  FIG. 1  engaging a brachytherapy needle during an implantation procedure. 
           [0012]      FIGS. 3A-G  depict alternative shapes for a notch defined by the brace of  FIG. 1 . 
           [0013]      FIG. 4  depicts an alternative brace of the present invention for a brachytherapy needle. 
           [0014]      FIG. 5  depicts the brace of  FIG. 4  positioned on a brachtherapy needle. 
           [0015]      FIG. 6  depicts the brace of  FIG. 4  formed as a bi-component device. 
           [0016]      FIG. 7  depicts another brace of the present invention for a brachytherapy device positioned on a brachytherapy needle. 
           [0017]      FIG. 8  depicts yet another brace of the present invention positioned on a brachytherapy needle. 
           [0018]      FIG. 9  depicts still another brace of the present invention. 
           [0019]      FIG. 10  depicts still yet another brace of the present invention. 
           [0020]      FIG. 11  depicts even yet another brace of the present invention. 
           [0021]      FIG. 12  depicts even still yet another brace of the present invention. 
           [0022]      FIG. 13  depicts even still yet another brace of the present invention. 
           [0023]      FIG. 14  depicts even still yet another brace of the present invention. 
           [0024]      FIG. 15  depicts still yet even another brace of the present invention. 
           [0025]      FIGS. 16-18  depicts even still another brace of the present invention. 
           [0026]      FIG. 19  depicts yet still another brace of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0027]    The present invention provides braces for brachytherapy needles in order to reduce bowing (or bending or buckling) of the needle due to the longitudinal loads during insertion into a patient. The braces offer convenience to the physicians using the needles by reducing the need to manually hold the needle at a location near the radioactive brachytherapy load during needle insertion. Thus, the braces of the present invention help reduce extremity exposure to the activity of the needle loads by either providing the physician some degree of stand-off from the needle while manipulating it, and/or through the additional shielding the brace provides. Certain of the braces are connected to a stylet lock at the hub of the needle so as to ensure that the brace does not come off of the needle during transportation or handling of the needle prior to implantation. 
         [0028]    The braces may be made of suitable materials which provide the structural rigidity to minimize bending of the needles during insertion into a patient. It is further contemplated that the braces may be formed from a material, or materials, which provide additional shielding against the activity of the needle loads while also providing a sufficient grip on the needle to resist movement due to gravitational or inertial forces. It may be desirable for the braces of the present invention to be able to slide along the needle body should the needle to penetrate the patient a distance that is greater than the brace&#39;s closest distance to either the patient or the needle grid through which the needle passes proximate to the patient. Certain braces are contemplated to be provided with the brace in position on the needle body, while other braces are to be applied to the needle by the physician prior to implanting the needle. It is further contemplated that any of the braces of the present invention could be provided with a brachytherapy needle in kit form. The needle may be either pre-loaded with a brachytherapy load. The brachytherapy load being either one or more brachytherapy seeds and/or spacers, or a stranded brachtherapy product where one or more seeds and/or spacers are provided in a carrier material or suture as is known in the art. 
         [0029]    The operating principle of the present invention is to provide a holding force along the needle body so as to reduce the bowing stress, which is a function of body length. Desirably, the brace is applied generally about the position of maximum bowing (were it to occur), or at a point about mid-way between the needle hub and the placement grid after the needle has been inserted into the grid but prior to penetration of tissue, although the exact placement may be selected by the physician. Once the needle as penetrated the dermis, the bowing forces are generally dissipated as the tissue offers far less resistance to further needle penetration. Thus it is desirable that the brace is able to slide along the needle body should continued insertion of the needle cause the brace to run into the grid body. 
         [0030]    With reference to  FIGS. 1 and 2 , the present invention provides a brace  10  for a brachytherapy needle. Brace  10  includes an elongate body  12  having opposed major surfaces  12  and  14 . Body  12  defines a notch  16  opening on a perimetrical edge  18  thereof. Notch  16  is defined to include a dimension larger than the cross-sectional width (typically, the diameter) of a brachytherapy needle  20 . 
         [0031]    Needle 20 is a suitable for performing brachytherapy procedures, such as 16-gage, 18-gage, or 20-gage needle. Needle  20  has a tubular needle body  22  having opposed first and second open ends,  24  and  26  respectively, and an elongate cylindrical body wall  28  extending therebetween. Needle body  22  defines an elongate passageway  30  extending in fluid communication with first and second openings  32  and  34  respectively defined by first and second open ends  24  and  26 . Needle  20  includes a brachytherapy load positioned within passageway  30  for dispensing out first end  24 , as is known in the prior art. Needle  20  typically includes a needle hub  36  at second end  26  and an elongate stylet  38  which is extendable through opening  34  and passageway  30  for dispensing the brachytherapy load. 
         [0032]    With particular reference to  FIG. 2 , needle  20  is typically inserted through a grid  40  positioned adjacent to a patient. Grid  40  includes a grid body  42  defining a number of parallel passages  44  therethrough in a standardized 2×2 array used for brachytherapy treatment, or dosing, plans. The physician can push on hub  36  to drive first end  24  of needle  20  into the patient towards the target tissue. In order to reduce any bowing, bending, or buckling of needle  20  during needle insertion, the physician may use their free hand to hold brace  10  so that needle body  22  extends generally transversely through notch  16 . As the expanse of notch  16  is generally slightly larger than the diameter of needle  20 , the physician may thus hold brace  10  at an oblique angle a to needle body  22 . Thus, needle body  22  is pinned between opposed notch edges  13  and  15  of opposing major surfaces  12  and  14 , respectively. It has been demonstrated that bowing of needle  20  can be reduced or even eliminated by providing a counter-acting holding force along needle body  22 . Desirably, brace  10  is positioned at a location about mid-way between hub  36  and grid  40  after needle  20  has been inserted into a passage  44  but prior to penetration of tissue. 
         [0033]    Referring now to  FIGS. 3A-G , the present invention contemplates that notch  16  of brace  10  may take different forms and be located at different positions than shown in  FIG. 1 . In each case, the notch is defined to include a dimension larger than the cross-sectional width of said needle body so as to receive the needle body therein such that a tilting of the brace body with respect to the needle body will provide the desired grip to steady the needle body against bowing. Additionally, for  FIGS. 3A-G , like numbering will denote like components. 
         [0034]    In  FIG. 3A , notch  16   a  is defined at a longitudinal end of brace body  10   a.  Each of the notches which open on a perimetrical edge of the brace body are contemplated to be located at either a longitudinal end of the brace body or to open transversely with respect to the brace body. In  FIG. 3B , notch  16   b  is defined to have a hook-shape. In  FIG. 3C , notch  16   c  is defined to have a first expanse in fluid communication with a second, larger, expanse. In  FIG. 3D , notch  16   d  is defined to have the shape of a bayonet-connector, or an L-shape. In  FIG. 3E , notch  16   e  is defined by either an arcuate or U-shaped notch edgewall. In  FIG. 3F , notch  16 F is defined as a bounded arcuate aperture opening on both major surfaces of brace body  12   f.  In  FIG. 3G , notch  16   g  is defined as bounded rectilinear aperture opening on both major surfaces of brace body  12   g.    
         [0035]      FIGS. 4-6  depict a brace  110  of the present invention. Brace  110  includes an elongate cylindrical brace body, or support body,  112  having opposed first and second open ends  114  and  116 . Brace body  110  includes a needle engagement member  118 . Needle engagement member  118  is an elongate cylindrical wall having an inner surface  120  defining an elongate brace passageway  122  extending in fluid communication between open ends  114  and  116 . First end  24  of needle  20  is inserted through brace passageway  122  so that brace  110  is retained on the outer surface  22   a  thereof. Brace  110  is desirably sized to slideably engage outer surface  22   a  of needle  20 , that is, brace  110  is able to hold its place on needle  20  against gravitational or inertial forces, but is still relatively easy to be slid therealong. 
         [0036]    Brace  110  may be formed as a unitary structure, as shown in  FIG. 4 , or as a two-part structure as shown in  FIG. 5 . In  FIG. 5 , engagement member  118  of brace  110  is provided by an inner cylindrical body  124  extending within support body  112 . The present invention contemplates that support body  112  is formed from a structurally rigid material to resist the bowing of needle  20  and desirably from a material which attenuates radioactivity or provides additional shielding to a user or technician. Inner cylindrical body  124  is desirably formed from a softer material than support body  112 , such as a polymeric material, which can provide some give to needle body on which it is placed. 
         [0037]    The longitudinal length of brace  110  may be selected to satisfy the purpose of the present invention, to reduce the bowing of its respective needle. For example, while brace  110  may be from about 0.25 inches to 1 inch in length, the present invention contemplates that the length is only limited by the length of needle extending between the needle hub and the grid body when the needle has reached its maximum insertion depth. The thickness of brace  10  is selected to be sufficient for the needle on which it is to be positioned. It is further contemplated that brace body  112  forms one or more detents or projections which may be deflected to engage the needle body onto which it has been positioned. 
         [0038]      FIG. 7  depicts brace  210  having a brace body  112  (as described for  FIGS. 4-6 ) affixed to a stylet lock  212 . Stylet lock  212  includes an annular rim  214  through which stylet  38  extends locking engagement and a spacing arm  216  which holds brace body  112  a fixed distance from hub  36  of needle  20 . Spacing arm  216  is selected to be a length which still allows needle  20  to be inserted to the required dispense depth within the patient. Stylet lock engages hub  36  and stylet  38  and holds stylet  38  in place against gravitational and inertial forces but still allows the physician to advance stylet  38  within the needle passageway to effect dispensing of the brachytherapy load. 
         [0039]      FIG. 8  depicts brace  310  having a brace  110  (as described for  FIGS. 4-6 ) affixed to a stylet lock  212  (as described for  FIG. 7 ). Brace  310  includes a deflectable spacing arm  316  which limits the maximum spacing of brace body  110  from hub  36  of needle  20 , while allowing brace body  110  to be urged towards hub  36 . 
         [0040]      FIG. 9  depicts a brace  410  of the present invention. Brace  410  includes an elongate cylindrical brace body, or support body,  412  having opposed first and second open ends  414  and  416 . Brace body  412  also defines an elongate transversely-opening channel  415  along the length thereof. Brace body  410  includes a needle engagement member  418 . Needle engagement member  418  is an elongate cylindrical wall having an inner surface  420  defining an elongate brace passageway  422  extending in fluid communication between open ends  414  and  416 . First end  24  of needle  20  is inserted through brace passageway  422  so that brace  410  is retained on the outer surface  22   a  thereof. Alternatively, should brace body be formed of a sufficiently flexible material, the present invention contemplates that needle  20  may be inserted through channel  415  into passageway  422 . Brace  410  is desirably sized to slideably engage outer surface  22   a  of needle  20 , that is, brace  410  is able to hold its place on needle  20  against gravitational or inertial forces, but is still relatively easy to be slid therealong. The present invention contemplates that brace  410  extends sufficiently about needle  20  to prevent needle  20  from bowing back through channel  415 . The present invention also contemplates that multiple braces  410  may be applied to a single needle, in which case it would be desirable to arrange the channels  415  of each brace to extend in different orientations about needle  20 . 
         [0041]      FIG. 10  depicts a brace  510  of the present invention. Brace  510  includes a planar body  512  having opposed major faces  514  and  516 . Body  512  defines a number of passages  518  extending in parallel therethrough, arranged in a 2×2 matrix array corresponding to a brachytherapy dose plan, to open on faces  514  and  516 . The present invention contemplates that brace  510  may have more than a single needle extending therethrough, desirably each needle loaded and positioned in accordance with the dose plan. As only a single needle will be dispensed at a time, brace  510  may be held by the physician at a location from the dispensing needle that reduces any bowing of that needle during needle penetration into a patient. Brace  510  may be shipped with a carrier kit for a dose plan as is more fully described in copending patent application, attorney docket number PM-0986P, filed on even date herewith, the entire contents of which are hereby incorporated by reference as if fully disclosed herein 
         [0042]      FIGS. 11-13  depict various clamp braces of the present invention. The clamp braces of the present invention provide spring-loaded clamps for holding a portion of a brachytherapy needle at multiple points therealong so as to minimize deflection of the needle during insertion into a patient. The clamps of the present invention are contemplated as either grasping the surface of the needle at distinct points or along a length of the surface thereof. The clamp braces include opposing first and second surfaces which are urgeable towards each other by a resilient spring means for engaging the tubular body of said needle. A physician opens the clamp brace by overcoming the spring means to urge the opposed surfaces away from each other so that the needle body may be inserted therebetween. The physician then relaxes the opening force to allow the opposing surfaces to close about the needle body. It is contemplated that a single clamp brace may be use for each of the needles provided for a single dose plan, although each needle may alternatively be provided with its own clip. 
         [0043]    In  FIG. 11 , clamp brace  610  includes opposing first and second surfaces  612  and  614  which are urgeable towards each other by a resilient spring means  616  for engaging the tubular body of needle  20 . Desirably, one or both of first and second surfaces  612  and  614  defines an elongate arcuate channel  620  and  622  which conform about needle body  22  to thereby provide support fully thereabout. It is contemplated that arcuate channels  620  and  622  are sized to allow clamp brace  610  to grasp and hold onto needle  20  without slippage due to gravitational or inertial forces. 
         [0044]    In  FIG. 12  clamp brace  710  includes opposing first and second surfaces  712  and  714  which are urgeable towards each other by a resilient spring means  716  for engaging the tubular body of needle  20 . Desirably, one or both of first and second surfaces  712  and  714  defines an elongate arcuate channel  720  and  722 . Arcuate channels  720  and  722  thus provide a semi-cylindrical wall which together conform about needle body  22  to thereby provide support thereabout. It is contemplated that arcuate channels  720  and  722  are sized to allow clamp brace  710  to grasp and hold onto needle  20  without slippage due to gravitational or inertial forces. Clamp brace  710  further includes an elongate first arm  724  supporting first surface  712  at one end thereof and an elongate second arm  726  supporting second surface  714  at one thereof. First and second arms are pivotally connected so as to allow movement of first surface  712  towards and away from second surface  714 . 
         [0045]    In  FIG. 13 , clamp brace  810  includes a support member having opposing first and second surfaces  812  and  814  which are urgeable towards each other by a resilient spring means  815  for engaging the tubular body of needle  20 . First and second surfaces  812  and  814  are provided as opposing surfaces of opposed U-shaped walls  816  and  818 . It is further contemplated that either U-shaped wall  816  or  818  may be instead provided by a pair of transversely-spaced elongate arms  816   a,    816   b  or  818   a,    818   b,  respectively. Clamp brace  810  thus provide two pairs of spaced hold points for needle  20 . 
         [0046]      FIG. 14  depicts another brace  910  of the present invention. Brace  910  includes a brace body  912  and includes an elongate cylindrical inner surface  914  which defines opposed apertures  916  and  918  and an elongate needle passage  920  extending in fluid communication therebetween. Brace body  912  includes an outer surface  922  shaped to ergonomically conform to a user&#39;s hand or fingers. The length of body  912  is desirably limited to allow needle  20  to be inserted to a desired depth within a patient. It is contemplated that brace  910  may be preferably used in procedures where a physician desires to grip about needle  20 . As such, brace body  912  is desirably formed from a radiation-shielding material so as to further protect the extremity gripping brace  910 . 
         [0047]      FIG. 19  depicts another brace  1210  of the present invention. Brace  1210  includes an elongate cylindrical brace body  912  having an elongate cylindrical surface  1214  defining opposed apertures  1216  and  1218  and an elongate needle passage  1220  extending in fluid communication therebetween. Brace body  1212  includes an elongate cylindrical outer surface  1222 . The length of body  1212  is desirably limited to allow needle  20  to be inserted to a desired depth within the patient. Brace body further includes a hub-engaging surface  1224  for limiting insertion of needle  20  through passage  1220 . Brace body  1212  is desirably formed from a radiation-shielding material although may be formed of a suitable metal or rigid plastic. 
         [0048]      FIG. 15  depicts another brace  1010  of the present invention. Brace  1010  is similar in concept to braces  210  in that a brace body  110  is connected to a stylet lock  212  by a two-segment spacing arm  1126 . Spacing arm  1026  includes a first segment  1026   a  extending from lock  212  substantially normal to needle  20  and a second segment  1026   b  connected between brace body  112  and first segment  1026   a.  Spacing arm  1026  thus provides a transverse stand-off from the brachytherapy load within needle  20  where a physician may hold brace  1010  at a lower risk of exposure. The present invention further contemplates that the brace  410  may be incorporated into this design as well. 
         [0049]      FIGS. 16-18  depict brace  1110  of the present invention. Brace  1110  is similar in concept to brace  310  in that a brace body  1112  is urgeable towards a stylet lock  1114  located at the needle hub. Brace  1110  includes bushing rod  1130  which is receivable within a bushing passageway  1132  defined by the brace body  1112 . The loaded needle is inserted through the aperture in stylet lock  1114  and then through passageway  1142  defined through brace body  1112 . The needle hub will abuttingly engage stylet lock  1114  as it is too large to pass through its aperture. The needle hub will travel towards brace body  1112 , and thus be inserted into a patient out the opposite end of body  1112 , with stylet lock  1114  as bushing rod  1130  extends into bushing passage  1140 . The bulk of brace body  1112  will counter the deflection of the needle body as it is inserted into the patient. 
         [0050]    The present invention further provides a kit for a brachytherapy procedure, the kit includes an elongate needle having a tubular needle body and a brace of the present invention adapted to engage a portion of said body wall of said needle so as to reduce bending of said needle as said needle is inserted into a patient. The needle desirably includes at least one brachytherapy source positioned within said passageway thereof. The kit desirably also includes an elongate stylet adapted to be extendable through the needle so as to effect dispensing of the brachytherapy source. The kit is desirably provided sterilized within a sealed container which maintains the sterility of the kit components. 
         [0051]    While the particular embodiment of the present invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the teachings of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.