Abstract:
An applicator for delivering radioactive seeds to a prostate gland or other internal organ includes a disposable inner part formed by two mating parts that collectively define a longitudinally-extending throughbore when joined together. The disposable inner part is sandwiched between two applicator half shells secured to one another by a slide member. The throughbore is discontinuous at a cartridge-receiving chamber that accommodates a multiple seed-containing cartridge, completely shielded with a sliding inspection window. The trailing end of a transition tube is held within the throughbore on a leading side of the discontinuous throughbore and the leading end of the transition tube extends into the lumen of an elongate needle. Seeds are expelled by a push rod that extends sequentially through a seed discharge chamber in the cartridge, the transition tube, and the needle. In a first alternative embodiment the disposable inner part is one piece and in a second it is formed integrally with the half shells.

Description:
This application is a continuation-in-part of Ser. No. 09/829,190 filed Apr. 9, 2001 now U.S. Pat. No. 6,561,967. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates, generally, to a surgical tool for implanting radioactive seeds into a prostate gland or other internal organ. More particularly, it relates to a tool having disposable parts. 
     2. Description of the Prior Art 
     Radioactive seeds are implanted into a cancerous prostate gland to kill the tumor or tumors therein. Such seeds may also be used to attack tumors in other internal organs of the body. 
     In use, an applicator comes into contact with a patient&#39;s blood and other body fluids. Earlier applicators were therefore designed to be disposed of after use. 
     For example, U.S. Pat. No. 6,213,932 to the present inventor discloses a disposable applicator having the general appearance of a hypodermic syringe. It includes a transparent plastic cartridge for holding a plurality of radioactive tumor-killing seeds. Since the entire device is disposable after use, materials used in its construction must be re-cycled to avoid wasting such materials. 
     Pending U.S. patent application Ser. No. 09/829,190, now U.S. Pat. No. 6,561,967 also to the present inventor, improves upon the patented tool by providing an applicator having a plurality of cartridges that are stored on the body of the applicator so that a new cartridge is easily retrieved when all of the seeds have been discharged from an old cartridge. That patent application is incorporated herein by reference. The applicator of the pending patent application includes a disposable section from the needle to where the seeds are deployed from the cartridge. This represents an improvement over the earlier device because the entire applicator need not be discarded after use. 
     However, the patent pending applicator is not easily disassembled for cleaning. 
     It would therefore be advantageous if an applicator were provided that could be easily disassembled for cleaning. It would be even more advantageous if only the parts of an applicator that directly contact body fluids would be disposable while the rest of the applicator could be taken apart and cleaned easily for re-use. 
     Another drawback of earlier devices is that complete shielding of the cartridges precludes visual inspection of the seeds therewithin. A physician using an applicator would prefer to visually inspect the cartridges to see how many are remaining in a cartridge at any given time. If the cartridge is shielded (offers radiation protection), it is no longer transparent. 
     However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the pertinent art how such need could be fulfilled. 
     SUMMARY OF THE INVENTION 
     The long-standing but heretofore unfulfilled need for an improved cartridge and applicator for implanting radioactive seeds in internal organs is now met by a new, useful, and nonobvious invention. The invention includes a disposable internal part that comes into contact with a patient&#39;s blood and other body fluids. The disposable inner part is made of two elongate half parts and each half part has a longitudinally-extending groove formed therein. Moreover, each of the half parts has half of a cartridge housing formed therein as well. An elongate throughbore is formed by joining together the two half parts. Specifically, the elongate throughbore is formed by juxtaposition of the longitudinally-extending grooves. 
     A cartridge housing is also formed by joining together the two half parts. More particularly, the cartridge housing is formed by juxtaposition of the halves of the cartridge housing formed in said halves of said disposable inner part. 
     The elongate throughbore is discontinuous at the cartridge housing and has a trailing part on a trailing side of the cartridge housing and a leading part on a leading side of the cartridge housing. 
     The novel applicator further includes a polyimide transition tube having a trailing end captured by the leading part of the elongate throughbore. The transition tube has a leading end that extends from the elongate throughbore in leading relation thereto and the transition tube leading end is adapted to be positioned within a lumen of an elongate needle that has a sharp distal end for penetrating tissue. 
     The novel applicator outer shell is formed by two half shells. Each of the two outer half shells has a longitudinally-extending half-channel formed therein. An elongate channel is formed by joining together the two half shells in juxtaposition with one another. 
     A cartridge housing-receiving recess is formed in each of the half shells. Each half channel is discontinuous at the cartridge housing-receiving recess. The disposable inner part, including the cartridge housing, is disposed in sandwiched relation between the half shells when the half shells are in juxtaposition with one another. 
     A longitudinally-extending groove is formed in an external side wall of each of the half shells. A slide member has a generally “U”-shaped configuration that includes a pair of upstanding side walls projecting from a base wall in parallel relation to one another. A longitudinally-extending tongue is formed in each side wall of the pair of side walls. The longitudinally-extending tongues protrude toward one another so that the longitudinally-extending tongues respectively slideably engage the longitudinally-extending grooves formed in the exterior side walls of the applicator half shells. 
     The applicator half shells are held in juxtaposition to one another by the slide member to form the applicator shell. Removal of the slide member from the applicator half shells enables cleaning of the slide member and the applicator half shells. 
     An elongate rod is secured to and projects from the slide member in leading relation thereto. A “U”-shaped support member is secured to a leading end of the elongate rod. 
     A transversely disposed handle is secured to a trailing end of a preselected applicator half shell. The transversely disposed handle is centered with respect to the applicator shell when the applicator half shells are joined together. 
     The novel seed cartridge for holding radioactive seeds includes a seed housing adapted to hold a plurality of radioactive seeds. The seed housing includes a shielded front plate and a shielded door is formed in the front plate. The shielded door is adapted to be opened and closed so that seeds within the seed housing may be viewed when the shielded door is open and so that the seeds within the seed housing may not be viewed when the shielded door is closed. The shielded door and shielded front plate protect an ambient environment from radiation when the door is closed. 
     More particularly, a vertically extending opening is formed in the front plate and a vertically extending tongue is formed in opposite vertically extending edges of the vertically extending opening. A vertically extending groove is formed in each vertically extending edge of the shielded door and a door handle is secured to the shielded door so that a user may slide the door in the opening in a first direction to view seeds disposed in the housing and so that a user may slide the door in the opening in a second direction to close the door. 
     In a second embodiment of the invention, the disposable internal parts are integrally formed with one another. 
     In a third embodiment of the invention, the disposable internal parts are integrally formed with the two applicator half shells. 
     An important object of this invention is to provide an applicator having disposable internal parts that directly contact a patient&#39;s blood and other body fluids. 
     Another important object is to provide an applicator that is easily disassembled so that the internal parts requiring disposal are easily separated from the rest of the applicator for such disposal. 
     Still another object is to provide an applicator where the parts thereof that do not require disposal are easily assembled and disassembled and easily cleaned for re-use. 
     Yet another object is to provide a cartridge having a sliding door so that a physician may slide the door open to view the seeds, and to slide the door closed to restore the shielding function of the door, thereby preventing radiation leakage in all directions. 
     These and other important objects, advantages, and features of the invention will become clear as this description proceeds. 
     The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts that will be exemplified in the description set forth hereinafter and the scope of the invention will be indicated in the claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which: 
     FIG. 1 is an exploded perspective view of the disposable internal parts of the novel applicator; 
     FIG. 2 is a perspective view of the assembled internal parts and further depicting how a luer lock is attached thereto; 
     FIG. 3 is an exploded perspective view depicting the applicator shell that houses the disposable internal parts; 
     FIG. 4 is a perspective view depicting the applicator shell in its assembled configuration and further depicts how an elongate needle is attached to the luer lock fitting; 
     FIG. 5 is a perspective view depicting a slide member that holds together the two parts of the applicator shell and that further provides a needle support; 
     FIG. 6 is a perspective view depicting the slide member in its assembled configuration with the applicator shell and further depicting a cartridge and seeds in exploded view; 
     FIG. 7 is a perspective view like FIG. 6 but further adds an elongate plunger rod that pushed radioactive seeds from a seed discharge chamber in the applicator through the elongate needle and into an internal organ; 
     FIG. 8 is a perspective view depicting the plunger of FIG. 7 when fully inserted into the applicator so that a seed is discharged from the distal end of the elongate needle; 
     FIG. 9 is a perspective view of a cartridge with the viewing door closed; 
     FIG. 10 is a perspective view of the cartridge of FIG. 9 with the seed viewing door open; 
     FIG. 11 is an exploded perspective view of an embodiment where the disposable internal parts of the novel applicator formed of three parts in FIG. 1 are combined into one part; 
     FIG. 12 is a perspective view depicting an assembly that is alternative to the assembly of FIG. 3 where the applicator shell that houses the disposable internal parts is assembled prior to the luer lock base being inserted thereon; 
     FIG. 13 is a perspective view depicting the assembly of the parts depicted in FIGS. 11 and 12, which assembly is the same as depicted in the upper left of FIG. 4; 
     FIG. 14 is an exploded perspective view of an alternative embodiment of the applicator half shells where the internal disposable parts are eliminated as separate parts and become an integral part of the applicator half shells; 
     FIG. 15 is a perspective view depicting an alternative assembly where the applicator half shells of FIG. 14 are joined to one another prior to the mounting of the luer lock base thereto; and 
     FIG. 16 is a perspective view depicting the assembly of the parts depicted in FIG. 15, which results in the same assembly as depicted in the upper left half of FIG.  4  and in FIG.  13 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, it will there be seen that the reference numeral  10  denotes an illustrative embodiment of the present invention as a whole. 
     All of the parts denoted by the reference numeral  10  are the internal, disposable parts of the novel applicator and are hereinafter referred to as the “guts.” The guts are the parts of the applicator that come into contact with the blood and other body fluids of the patient. 
     Guts  10  include parts  12 ,  14 , and  16 . Part  12  has an elongate straight base and a plurality of ears, collectively denoted  18  integrally formed therewith in longitudinally spaced apart relation to one another. Each ear  18  is centrally apertured as at  20 . 
     Part  14  has an elongate straight base and a plurality of ears, collectively denoted  22  integrally formed therewith in longitudinally spaced apart relation to one another. Each ear  22  has a centrally mounted protrusion  24  that interlocks with an associated central aperture  20  to thereby join parts  12  and  14  to one another. The interconnection between parts  12  and  14  may rely on a press fit or an adhesive may be used to supplement the interconnection. 
     Half cartridge housing  26  is formed integrally with part  12  and half cartridge housing  28  is formed integrally with part  14 . As best understood in connection with FIG. 2, said half cartridge housings  26 ,  28  together form cartridge housing  30  when parts  12  and  14  are joined to one another. 
     Returning to FIG. 1, it will there be seen that groove  32  is formed along the entire extent of part  14 . A mating groove, not shown, is formed in part  12  so that an elongate bore that extends from the trailing end of the assembled parts  12  and  14  to the leading end thereof is formed when said two parts are joined together as depicted in FIG.  2 . 
     As best understood in connection with FIG. 1, transition tube  16 , preferably formed of polyimide, has a slightly enlarged trailing end  16   a  that is received with the elongate bore formed when groove  32  formed in part  14  and its unillustrated counterpart formed in part  12  are in juxtaposition with another. Groove  32  and its unillustrated counterpart are slightly enlarged as at  32   a  to accommodate the slightly enlarged trailing end  16   a  of polyimide transition tube  16  so that when parts  12  and  14  are joined to one another in sandwiching relation to transition tube  16 , said enlarged trailing end  16   a  is captured within said enlargement  32   a  to ensure that polyimide transition tube  16  does not slide out of said throughbore. 
     Polyimide transition tube  16  is depicted in its captured relation to parts  12  and  14  in FIG.  2 . 
     Returning again to FIG. 1, it should be observed that groove  32  formed in part  14  and its unillustrated counterpart formed in part  12  is discontinuous at cartridge housing  30 . When a cartridge is positioned within cartridge housing  30 , a radioactive seed is positioned in alignment with the throughbore formed by groove  32  and its unillustrated counterpart. An elongate plunger, not depicted in FIGS. 1 and 2, is introduced into the trailing end of the throughbore defined by disposable guts  10  and the leading end of said plunger bears against the trailing end of the seed in cartridge housing  30  and pushes it towards the leading end of the throughbore so that said seed enters into transition tube  16 . The leading end of polyimide transition tube  16 , denoted  16   b  in FIG. 1, is received within the lumen of an elongate needle, not illustrated in FIGS. 1 and 2, that is in turn inserted into the prostate or other organ into which the radioactive seeds are to be implanted. 
     As indicated in FIGS. 2 and 3, a luer lock base  34  or equivalent device is mounted to transition tube  16 . Luer lock base  34  is adapted to provide a mounting means for any luer lock or screw-in type needle. 
     Applicator shell  40 , depicted in FIG. 4, is formed of two parts  36  and  38  as best understood in connection with FIG.  3 . Half channel  42  formed in part  38  has an unillustrated counterpart in part  36  to accommodate guts  10  when parts  36  and  38  are assembled together. Recesses  44  accommodate ears  22  and unillustrated recesses formed in part  36  accommodate ears  18 . Recesses  46  accommodate cartridge housing  30  and annular groove  48 , only half of which is depicted, accommodates flange  50  formed in the trailing end of luer lock base  34 . Luer lock base  34  abuts the leading end of applicator shell  40  when it is fully assembled as depicted in FIG.  4 . 
     Transversely disposed handle  52  is formed integrally with applicator half shell  38  at the trailing end thereof. 
     Longitudinally-extending bore  54  is formed in said handle  52  to admit a pushrod into the throughbore formed when the two parts of guts  10  are assembled as mentioned above. 
     Openings  56  formed in applicator half shell parts  36  and  38  are adapted to accommodate cartridges that are not in use when a seed-implanting procedure is performed, as more fully set forth in the incorporated pending patent application. 
     It should also be observed in FIGS. 3 and 4 that elongate slots  58  and  60  are formed in applicator half shell parts  36  and  38 , respectively. Said elongate slots extend the entire extent of said half shell parts and are formed on respective exterior surfaces thereof. 
     FIG. 4 further depicts luer lock main body  62  that engages luer lock base  34  in a well-known way. Elongate needle  64  is engaged at its trailing end by said luer lock main body  62 . Radioactive seeds, not depicted in FIG. 4, are driven from the sharp distal end  66  of elongate needle by a push rod, not depicted in said Figure, when the inventive structure is in use. Sharp distal end  66  of needle  64  is adapted to penetrate tissue. 
     FIG. 5 depicts slide member  68  having an elongate “U” or channel-shaped structure including a pair of upstanding side walls projecting from a base wall in parallel relation to one another. A longitudinally-extending tongue  70 ,  72  is formed in each side wall of said pair of side walls. Said longitudinally-extending tongues protrude toward one another so that they respectively slideably engage longitudinally-extending grooves  58  and  60 , respectively, formed in said exterior side walls of said applicator half shells as indicated by the dotted assembly lines. Slide member  68  is used to hold together the two half parts  36  and  38  of applicator shell  40 . 
     As depicted in FIG. 6, slide member  68  abuts handle  52  when the novel applicator is in use. Applicator shell  40  is centered with respect to handle  52  when applicator shell half parts  36 ,  38  are secured to one another by slide member  68 . 
     As best depicted in FIG. 5, elongate rod  74  is secured to and projects from slide member  68  in leading relation thereto. “U”-shaped support member  76  is secured to the leading end of elongate rod  74 . 
     As perhaps best understood in connection with FIG. 6, “U”-shaped support member  76  cooperates with handle  52  to provide a stable support for applicator shell  40  when it is in use. As explained in the incorporated pending patent application, said seeds may be implanted by holding applicator shell  40  against movement and advancing the push rod, or by holding the push rod against movement and retracting applicator shell  40 . Either relative movement expels the seeds through distal end  66  into an internal organ. In the preferred technique, handle  52 , slide member  68 , and “U”-shaped support member  76  collectively anchor against the needle grid and serve as a purchase to retract needle  64  as the seeds are deployed. 
     FIG. 6 further depicts seed cartridge  78  that holds a plurality of seeds  80 . The leading end of seed cartridge  78  is inserted into cartridge housing  30  as indicated by the dotted lines when the novel assembly is in use. The structure of seed cartridge  78  is fully disclosed in the incorporated pending patent application. 
     Seed cartridge  78  of this invention differs, however, in that it includes an opaque, shielded, slideably-mounted window that the physician may momentarily slide open to view seeds  80  and slide closed to provide shielding in all directions. The window rides on a tongue and groove track, disclosed hereinafter. 
     FIG. 7 depicts push rod  84  having handle  86  at its trailing end. The dotted line at the leading end of push rod  84  indicates how said push rod is introduced into the throughbore defined by the disposable guts of the applicator. 
     FIG. 8 depicts push rod  84  when fully inserted into said throughbore. A seed  80  is depicted being expelled into an internal organ from the leading end  66  of needle  64 . 
     FIG. 9 depicts seed cartridge  78  having cartridge handle  79  and a slideably mounted shielded door  88  of elongate vertical construction. Door handle  90  is formed integrally with door  88 . A vertically extending groove is formed in shielded door  88  in each of its opposite vertically extending edges. Each groove slideably engages a vertically extending tongue  92  formed on each side of vertically extending opening  94  which is formed in front plate  96  that forms a part of seed housing  97  of seed cartridge  78 . Neck  98  is urged into said seed housing  97  by biasing means  100 ,  100  that extend in tension between said seed housing  97  and said neck  98 . 
     The tongue and groove connection may be reversed, with a tongue formed in each vertically extending opposite edge of door  88  and a groove formed in each vertically extending opposite edge of opening  94 . 
     FIG. 10 depicts shielded door  88  in its open configuration. Seeds  80  can be seen and counted by the physician when said door is open. Door  88  is kept closed at all other times and its shielding along with the shielding of front cover  96 , rear housing  97 , and handle  79  prevent radiation from escaping into the ambient environment. 
     Applicator shell  40  and slide member  68  are easily cleaned and re-used. The absence of a need to re-cycle or discard said parts results in a significant saving of materials. 
     However, in an additional embodiment, applicator shell  40  could be formed integrally with disposable guts  10  so that only slide member  68  would be retained and cleaned. 
     An alternative assembly depicted in FIGS. 11-13 is best understood by referring again to FIG. 1 where internal disposable parts or guts  12 ,  14 , and  16  are depicted in unassembled configuration. In the assembly of FIG. 11, disposable internal parts  12 ,  14 , and  16  are pre-assembled, i.e., polyimide transition tube  16  is sandwiched between parts  12  and  14 . The integrally formed guts are denoted  10   a  in FIG.  11 . Applicator shell halves  36  and  38  are then brought into sandwiching relation to said guts as depicted in FIG. 12, prior to the addition of luer lock base  34  (FIG. 12) thereto. This differs from the assembly depicted in FIGS. 3 and 4 where luer lock base  34  is mounted to polyimide transition tube  16  (FIG. 3) prior to the step of bringing together applicator half shells  36 ,  38 . However, the next step of the alternative assembly procedure, where luer lock base  34  is mounted onto polyimide transition tube  16 , as depicted in FIG. 13, results in the same structure as depicted in the upper left of FIG.  4 . 
     Another improvement is depicted in FIGS. 14-16. As perhaps best understood by comparing FIGS. 11 and 14, disposable inner parts  12 ,  14 , and  16  are merged into, i.e., integrally formed with applicator half shells  36   a  and  38   a . Note that polyimide transition tube  16  is now formed and replaced with integral molding of half shell  36   a  and when part  16   a  of applicator half shell  36   a  is brought into juxtaposition with part  16   b  of applicator half shell  38   a . Similarly, groove  32  is now formed when half groove  32   a  formed in applicator half shell  38   a  is brought into juxtaposition with an unillustrated mating half groove formed in applicator half shell  36   a.    
     In this way, all three separate disposable inner parts  12 ,  14 , and  16 , are eliminated. As in the embodiment of FIGS. 11-13, applicator half shells  36   a ,  38   a  are assembled prior to the mounting of luer lock base  34  onto polyimide transition tube  16   a  and the final structure is depicted in FIG.  16 . Groove  32   a  is formed in half shell  36   a  and  38   a  and is not defined by the disposable internal parts as in the earlier embodiments. Groove  32   a  and its unillustrated counterpart formed in half shell  36   a  are thus in fluid communication with the lumen formed by integrally formed transition tube  16 . 
     It will thus be seen that the objects set forth above, and those made apparent from the foregoing description, are efficiently attained. Since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention that, as a matter of language, might be said to fall therebetween. 
     Now that the invention has been described,