Abstract:
An apparatus and method for loading brachytherapy carriers with radioactive seeds in order to implement brachytherapy treatment protocols with more precise and predictable dosimetry. These apparatuses and methods enable a medical team to create a radionuclide carrier for each patient and tumor reliably, reproducibly and efficiently.

Description:
PRIORITY CLAIM 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/696,293, filed on Apr. 24, 2015, entitled “APPARATUS AND METHOD FOR LOADING RADIOACTIVE SEEDS INTO CARRIERS”. The disclosure of the foregoing application is hereby incorporated by reference in its entirety. 
     
    
     FIELD 
       [0002]    The invention generally relates to improvements to radioactive brachytherapy. 
       BACKGROUND 
       [0003]    Tumors in living organisms are highly variable in size, location and their amount of infiltration into normal tissues, and the variability of tumors in general make them very difficult to treat with a one-size fits all approach. Furthermore, the extent of tumors and/or void created upon debulking are typically not known until presented in the operating room. Thus the options necessary to effectively treat a tumor or tumor bed need to be quite diverse. 
         [0004]    Brachytherapy involves placing a radiation source either into or immediately adjacent to a tumor. It provides an effective treatment of cancers of many body sites. Brachytherapy, as a component of multimodality cancer care, provides cost-effective treatment. Brachytherapy may be intracavitary, such as when treating gynecologic malignancies; intraluminal, such as when treating esophageal or lung cancers; external surface, such as when treating cancers of the skin, or interstitial, such as when treating various central nervous system tumors as well as extracranial tumors of the head and neck, lung, soft tissue, gynecologic sites, rectum, liver, prostate, penis and skin. 
       SUMMARY 
       [0005]    The systems, methods, and devices described herein each have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this disclosure, several non-limiting features will now be described briefly. 
         [0006]    In one embodiment, an apparatus comprises a loader having a top surface, an opposing bottom surface, and a receiving surface therebetween, the loader further comprising: a loading bed configured to contain a radioactive seed carrier, the carrier comprising collagen and configured to contain a radioactive seed, the carrier having a first surface, and an opposing second surface; and a loading port through the receiving surface, the loading port defining a channel configured to receive an injection device. In one embodiment, the injection device comprises a distal end configured for insertion into the loading port, an injection channel configured to contain a radioactive seed, and a plunger having a first end comprising a longitudinal rod extending at least partially within the injection channel and a second end outside of the injection channel configured for engagement by a human operator in order to move the longitudinal rod within the injection channel. In one embodiment, the distal end of the injection device is configured for at least partial insertion into the loading port in order to move the radioactive seed out of the injection device into the carrier in response to pushing the second end of the plunger towards the distal end of the injection device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The principles of the present invention will be apparent with reference to the following drawings, in which like reference numerals denote like components: 
           [0008]      FIG. 1  is a cross-sectional diagram of a loader containing a carrier and an injector. 
           [0009]      FIG. 2  is a cross-sectional view of another embodiment of a carrier that includes a port having an alignment interface configured to engage with a corresponding alignment interface at the distal end of the injector. 
           [0010]      FIG. 3  is a cross-sectional view of several loaders, each with different alignment interfaces that are configured for engagement with a corresponding alignment interface of an injector. 
           [0011]      FIG. 4  is a cross-sectional view of an example carrier, a guide path tool, and injector. 
           [0012]      FIGS. 5A and 5B  are cross-sectional views of example multi-port loaders and injectors. 
           [0013]      FIG. 6  is a cross-sectional view of a multi-port loader that is being loaded using a single channel injector (as discussed above with reference to  FIG. 2 , for example). 
           [0014]      FIG. 7  is a cross-sectional view of a loader and a carrier during a process of loading the loader with the carrier. 
           [0015]      FIG. 8  is a cross-sectional view of the same loader, including loading bed, as illustrated in  FIG. 7 , but now the loading bed loaded with a carrier cartridge that holds multiple carriers in place. 
           [0016]      FIG. 9  illustrates three additional example carrier cartridges containing carriers of varying shapes. 
           [0017]      FIG. 10  is a cross-sectional view of a loader having a loading bed that includes wells sized to receive circular carriers. 
           [0018]      FIG. 11  illustrates an example use case of the loader and injector systems discussed herein. 
           [0019]      FIG. 12  illustrates an injector that includes a loading port for loading seeds into the injection channel. 
           [0020]      FIG. 13  is a diagram illustrating an example external view of an injector with a magazine port, and a seed magazine configured for attachment to the injector via the magazine port. 
           [0021]      FIG. 14  illustrates a cross-sectional view of an injector in various states as a seed magazine is used to move seeds into the injection channel one at a time for injection into a carrier. 
           [0022]      FIG. 15A  illustrates an example “auto loader” that automates much of the process of loading seeds into carriers. 
           [0023]      FIG. 15B  illustrates another example autoloader, including a cross-sectional view of the loader. 
           [0024]      FIG. 16  illustrates a top and a front view of an auto loader. 
           [0025]      FIG. 17  illustrates example components that are usable in an automated process of loading seeds into carriers. 
           [0026]      FIG. 18  illustrates another seed injection system that may be used in place of the seed injection system of  FIG. 17  and/or in any other automated seed injection embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Although certain preferred embodiments and examples are disclosed below, inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and to modifications and equivalents thereof. Thus, the scope of the claims appended hereto is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein. 
       Definitions 
       [0028]    In order to facilitate an understanding of the systems and methods discussed herein, a number of terms are defined below. The terms defined below, as well as other terms used herein, should be construed to include the provided definitions, the ordinary and customary meaning of the terms, and/or any other implied meaning for the respective terms. Thus, the definitions below do not limit the meaning of these terms, but only provide exemplary definitions. 
         [0029]    Tumor bed: an anatomical area where a tumor exists and/or an area surrounding a surgically removed tumor, such as a cranial cavity from which a tumor was surgically removed. 
         [0030]    Brachytherapy: radiation treatment in which the source of radiation is placed close to the surface of the body, on the surface of the body, within the body, or in a tumor bed. 
         [0031]    Seed: a radioactive material that is configured for delivery of radiation to a tumor and/or tumor bed. A seed may be in various shapes and sizes, such as cylinder, cone, sphere, pyramid, cube, prism, rectangular prism, triangular prism, and/or any combination of these or other shapes. While seeds are generally referred to herein as cylindrical, any other shape or size of seed may alternatively be used in the various systems and methods discussed herein. Seeds may comprise any combination of one or more of multiple radioactive components, such as Cs 131, Ir 192, I125, Pd 103, for example. Seeds may include a protective outer shell that partially or fully encases the radioactive material. 
         [0032]    Carrier: a substrate that holds or contains a radioactive seed. Carriers may be configured for permanent implantation into a tumor bed, such as to provide radioactive energy to a tumor and/or area where a tumor has been removed in order to treat any remaining malignant tissue. Carriers can be composed of various materials and take on various shapes and sizes. Examples carriers, such as carriers having various sizes, shapes, configurations, etc., are included in the following patents, each of which is hereby incorporated by reference in its entirety and for all purposes:
       U.S. patent application Ser. No. 14/322,785, filed Jul. 2, 2014, now U.S. Pat. No. 8,876,684, entitled “Dosimetrically Customizable Brachytherapy Carriers And Methods Thereof In The Treatment Of Tumors,” and   U.S. patent application Ser. No. 14/216,723, filed Mar. 17, 2014, publication No. 2014/0275715, entitled “Dosimetrically Customizable Brachytherapy Carriers And Methods Thereof In The Treatment Of Tumors.”       
 
         [0035]    Tile Carrier (also referred to as “Tile”): type of carrier that is planar and maintains a two-dimensional planar geometry when placed in a tumors bed. 
         [0036]    Gore Carrier (also referred to as “Gore”): type of carrier that is 3-dimensional and conform to the treatment environment while maintaining the geometry necessary for an effective implant. In some embodiments, gores are initially planar and are reconfigured to take on a 3-dimensional shape, such as to form a hemispherical surface that may be placed into a similarly shaped tumor cavity. 
         [0037]    Loader: a device that aids in placement of radioactive seeds in carriers, such as via injection of seeds into carriers. A loader, also referred to herein as a “loading device,” may include multiple components, such as to hold a carrier in place and guide a delivery device, such as a needle or injector, into the carrier in order to place a seed at a precise location in the carrier. U.S. patent application Ser. No. 13/460,809, filed Apr. 30, 2012, now U.S. Pat. No. 8,939,881, entitled “Apparatus For Loading Dosimetrically Customizable Brachytherapy Carriers,” which is hereby incorporated by reference in its entirety for all purposes, describes several embodiments of loaders. As discussed further herein, loaders may be operated manually, such as by human operators, or may be fully automated, such that carriers can be loaded with seeds using an automated process. Alternatively, loaders may be configured to be automated in part and require manual operation in part. Each loader includes a loading bed, which is a portion of the loader configured to receive one or more carriers (and/or a carrier cartridge that houses multiple carriers) for loading of one or more seeds into the one or more carriers. 
         [0038]    Teletherapy: radiation treatment in which the source of the radiation is at a distance from the body. 
         [0039]    High Z Materials: any element with an atomic number greater than 20, or an alloy containing such materials. 
         [0040]    Hot material: a material that is Radioactive. 
         [0041]    Cold material: a material low in radioactivity or not radioactive. 
         [0042]    Dosimetry: a process of measurement and quantitative description of the radiation absorbed dose (rad) in a tissue or organ. 
         [0043]    Tumor: an abnormal growth of tissue resulting from uncontrolled, progressive multiplication of cells. Tumors can be benign or malignant. 
       Example Embodiments 
       [0044]    Described herein are various embodiments of loading devices and systems for enabling more precise, efficient, accurate, and/or convenient loading of radioactive seeds into radioactive carriers. The various loader configurations disclosed herein may be sterilizable single or multi-use devices for manual or automated loading (in real time or for pre-loading) of carriers (e.g., GammaTiles, GammaDots, GammaStars, or GammaGores provided by Gammatile, Inc.,) with radioactive seeds such as I 125, Cs 131 or Pd 111 or other materials. The loaders may be constructed of metal, plastic or composite material, and manufactured by casting, molding, stamping, forming or 3D printing. Embodiments of the loaders may include shielding either by way of construction with a high Z material, or with other materials with a sufficient dimension (thickness) to provide the necessary dose attenuation for a user. Alternative embodiments may remain unshielded, and be made of materials suitable for the purpose including but not limited to tungsten, stainless steel, nylon or plastic. 
         [0045]      FIG. 1  is a cross-sectional diagram of a loader  110  containing a carrier  120  and an injector  130 .  FIG. 1  illustrates an example process of loading a seed  132  into the carrier  120  using the injector  130  (also referred to as an “injection device” herein). In this example, the representations of the loader  110 , carrier  120 , injector  130 , and seed  132  are shown repeatedly in different states as the seed  132  is loaded into the carrier  120  using the injector  130 . The states are indicated by the illustrated “A”-“F” characters along the left margin of the figure. Similar labeling of states using characters in this same manner is used in other figures also to aid in illustrating example processes. 
         [0046]    Beginning at state A, the injector  130  has been loaded with a seed  132  in preparation for injecting the seed  132  into the carrier  120 , which is held in place in the loader  110 . The seed  132  may be loaded into the injector  130  in various manners, some of which are discussed herein with reference to other figures. For example, in one embodiment the seed is dropped into an opening at the distal end  131  of the injector  130 . In other embodiments, the seed is preloaded into the injector  130 , such as might be received from a manufacturer of the injector  130 , so that loading of the seed  132  into the injector  130  is not required by the individual that performs the process illustrated in  FIG. 1  (as well as other similar processes discussed herein). In other embodiments, automated loading systems may be used, such as a magazine that automatically inserts a seed into an injection channel  134  of the injector  130 . In one embodiment, seeds are sized to fit a channel similar to that of a syringe, such as a 17 gauge syringe channel. However, other sized seeds, either smaller, larger, different shape, etc., may be used in the embodiments discussed herein. For example, other sizes, shapes, dimensions, and characteristics of seeds, such as those provided in the various applications and patents incorporated by reference herein, may be used in the injection systems and methods discussed herein. 
         [0047]    In the embodiment of  FIG. 1 , the injector  130  comprises a plunger  136  attached to a plate  137  within the injection channel  134 , where the injection channel  134  is defined by an injection cylinder  133  having an inner diameter sized substantially the same as an outer diameter of the seed  132  and an out diameter sized substantially the same as the loading port  112 . With reference to dimensions discussed herein, substantially the same indicates that two measurements are the same or very close to one another, such as from 0.0-1.0 millimeters difference in diameter. For example, for a cylindrical seed  132  having an outer diameter of 0.8 mm, the injection channel  134  diameter (that is, the inner diameter of the injection cylinder  133 ) may be in the range of 0.8 mm-0.9 mm. This example seed diameter and example injection channel  134  diameter are considered substantially the same for purposes of this disclosure. 
         [0048]    In operation, the plunger  136  is pressed towards the distal end  131  of the injector  130  in order to cause the plate  137  to move within the injection channel  134 , thus forcing any object within the injection channel  134  out of the injection channel  134  at the distal end  131  of the injector  130 . In some embodiments, the rod  135  of the plunger may include one or more supports that extend outward from and are sized to engage with the inner diameter of the injection channel. For example, the rod  135  may include multiple (e.g., 3-9) appendages extending outward along a length (or some portion of) the rod, such that the outer ends of the appendages engage with the inner diameter of the injection channel and support the rod  135  as it moves through the invention channel  134 . 
         [0049]    For purposes of clarity in the figures, reference numerals provided with reference to state A of  FIG. 1  are not all included with reference to states B-F. In some embodiments, the plunger  136  may include a rod that is sized uniformly along a longitudinal length, without a separate larger plate  137 . For example the rod may have a diameter that is substantially the inner diameter of the injection channel (e.g., the entire rod may be the size of the plate  137  in the example of  FIG. 1 ). The embodiment of  FIG. 14  uses such a plunger  1136 , which may be used in other injector embodiments herein. 
         [0050]    Moving to state B, the distal end  131  of the injector  130  has been placed into a loading port  112  of the loader  110 . As noted above, in some embodiments the loading port  112  is sized to engage the outer diameter of the injection cylinder  133  of the injector  130 . For example, the loading port  112  diameter may be from 0.0-1.0 millimeters larger than the outer diameter of the injection cylinder. Other embodiments of loading ports are discussed below with reference to other figures. 
         [0051]    Next, at state C the plunger  136  has been moved towards the distal end  131  of the injector  130 , which has correspondingly moved the seed  132  further towards the distal end  131  of the injector  130 . Such movement may be performed by a human operator in a similar manner as a syringe may be used to administer an injection into a patient. 
         [0052]    Continuing to state D, the plunger  136  has been further moved toward the distal end  131  such that the seed  132  has been injected into the desired position/portion of the carrier  120 . With the seed  132  placed within the carrier  120 , the injector  130  may be removed from the loader  110 , such as is illustrated in state D of  FIG. 1 . In this example, removal of the injector  130  from the carrier  120  has created a void  122  in the carrier  120 . Depending on the characteristics of the carrier  120 , such as the material(s) of the carrier  120 , the void  122  may be smaller or larger than is illustrated in  FIG. 1 . For example, with certain materials, such as collagen, the collagen that is displaced by insertion of the seed  132  may return to its original position such that the void  122  is insignificant. With other materials, however, a void may remain that is large enough to allow movement of the seed  132  within the carrier  120 , such as when the carrier  120  is being moved and manipulated as it is moved into the treatment bed. Thus, in some embodiments, the seed  132  includes an adhesive on a distal end that enters the carrier  120  first, wherein the adhesive is configured to adhere to the carrier  120  and hold the seed  132  in place, even if a significant void  122  is created by the insertion process. 
         [0053]    Furthermore, in some embodiments a plug  124  may be placed into the void  122  to contain the seed  132  at the desired location within the carrier  120 . The plug  124  can be inserted in any manner, such as by manually pushing the plug  124  into the carrier through the loading port  112 , possibly using a tool such as a screwdriver or chisel to ensure that the plug  124  is entirely in the carrier  120 . Alternatively, the plug  124  can be placed using the injector  130  or a similar injection tool that allows placement of the plug in a similar manner as discussed above. In another embodiment, the seed and plug may be placed concurrently into the carrier  120  using an injector, such as by loading the injector with both the seed and plug, with the seed closest to the distal end  131  of the injector, and injecting both the seed  132  and plug  124  with the same movement of the plunger  136 . The plug  124  can include an adhesive on one or more of its outer surfaces, such as a distal end and/or on the outer diameter, so that once inserted into the carrier  120  the adhesive adheres the plug to the carrier material. In other embodiments, the seed  132  may be further secured in place within the carrier  120  by suturing or otherwise closing the void  122 . 
         [0054]    In one embodiment, multiple seeds  132  may be inserted using a plunger similar to plunger  136 , where the seeds may be separated by one or more spacers similar to plug  124 . For example, the injection channel  134  may be loaded with a seed, then a spacer (e.g., a material similar to the plug  124 , but sized to fit the spacing need(s)), then another seed. In this example, when the plunger is moved in order to evacuate the injection channel  134 , the seed, spacer, seed series of objects are all injected into the carrier. Such combinations of multiple seed and spacer insertions may be used in any of the other embodiments discussed herein also, whether by manual or automatic process. Additionally, depending on the embodiment additional seeds and spacers may be inserted, such as a combinations of three seeds separated by two spacers, four seeds separated by three spacers, etc. 
         [0055]      FIG. 2  is a cross-sectional view of another embodiment of a carrier  210  that includes a port  212  having an alignment interface  213  configured to engage with a corresponding alignment interface  214  at the distal end  231  of the injector  230 . Similar to the injector  130 , the injector  230  includes a plunger  236  connected to a plate  237  (or a plunger have a uniformly sized rod that without a separate plate  237 , such as in the example rod  1336  of  FIG. 14 ), which are configured to move a seed  232  through an injection channel  234  as the plunger  236  is urged towards the distal end  231  of the injector  230 . However, the injector  230  additionally includes an alignment interface  214  on its distal end  231  that is the mirror of the alignment interface  213  of the loader  210 . Thus, the injector  230  may be more securely interfaced with the loader  210  by means of the corresponding alignment interfaces of the loader  210  and the injector  230 . The alignment interfaces  213  and  214  may advantageously allow more precise insertion of the seed  232  into the carrier  120  as an orientation of the injector  230  can be more precisely maintained as the alignment interface  214  is engaged with the alignment interface  213  of the loader  210   
         [0056]    At state A of  FIG. 2 , the seed  232  has been loaded into the injector  230  and is ready for injection into the carrier  120 . The seed  232  may be loaded in any manner, including the example loading methods discussed herein. 
         [0057]    Moving to state B of  FIG. 2 , the injector  230  has been moved such that its alignment interface  214  is engaged with the alignment interface  213  of the loader  210 . With the injector  230  engaged with the loader  210 , at state C the plunger  236  may be urged towards the distal end  231  in order to push the seed  232  into the loader  210 , and further into the carrier  120  as shown at state D. Finally, the injector  230  may be removed from engagement with the alignment interface  213  at state E. In some embodiments, an adhesive on the seed  232  and/or a plug may be used in order to more securely maintain the position of the seed  232  within the carrier  120 , such as is discussed above with reference to  FIG. 1 . 
         [0058]      FIG. 3  is a cross-sectional view of several loaders, each with different alignment interfaces that are configured for engagement with a corresponding alignment interface of an injector. The loader  210  and its alignment interface  213 , which were discussed with reference to  FIG. 2 , are illustrated in  FIG. 3  for comparison with other possible alignment interfaces. Loader  310  includes a multi-tier interlocking alignment interface  313  and loader  320  includes a rounded interlocking alignment interface  323 . Alignment interfaces  213 ,  313 ,  323  correspond to mirror—image alignment interfaces on distal ends of the injectors, such that the injector may be held in a specific position and orientation with reference to the respective loaders and carrier within the loaders. 
         [0059]    Alignment interfaces  333  and  343  of loaders  330  and  340 , respectively, may even more securely engage injectors with the loaders. For example, alignment interface  333  includes a female threaded portion configured to engage a male threaded alignment interface on the distal end of an injector. Thus, in this embodiment the injector can be threaded onto the loader  330  to be held in place more securely, such that movement of the injector while engaged with the loader  330  is less likely. Once the seed has been injected into the carrier, the injector can be unscrewed from engagement with the alignment interface  333 . In the example of loader  340 , the alignment interface  343  includes one or more flexible clips around the circumference of the entry to the injection channel of the loader  340 . In this embodiment, the injector includes a corresponding one or more cavities at the distal end of the injector so that when the injector is engaged with the alignment interface  343 , the clips of the alignment interface  343  are depressed until the corresponding cavities in the injector reach the clips (e.g., as the user pushes the injector into the loading port of the loader), whereupon the clips enter the cavities and hold the injector securely against the loader. As shown in the example loader  340 , the alignment interface  343  may also include a shape similar to alignment interfaces  213 ,  313 ,  323 , with the injectors having engagement interfaces that mirror the interfaces  213 ,  313 ,  323 , in order to better hold the injector in place against the loader. In other embodiments any other configuration of alignment interfaces may be used in order to improve stability of engagement between an injector and loader as one or more seeds are injected into the loader. 
         [0060]      FIG. 4  is a cross-sectional view of an example carrier  120 , a guide path tool  410 , and injector  230 . The illustrated states of these components illustrates an example process of creating a guide channel  412  for insertion of a seed into the carrier  120 , such as by using a guide path tool  410  that comprises a punch, lance, needle, trochar, blade, laser, chisel, screwdriver, drill, and/or other similar device. In the example of  FIG. 4 , a punch  410  (which may be replaced with any other similar device in other embodiments, such as those mentioned above) is used to create the guide channel  412  in the carrier  120  in order to decrease tension from a seed against the carrier material, which could result in disfiguring or crushing the seed and/or the carrier in some embodiments. 
         [0061]    At state A in  FIG. 4 , the carrier  120  has been placed in the loader  210 . While the punch  410  is illustrated in conjunction with the loader  210 , the punch  410  and/or other similar guide channel creation instruments may be used in conjunction with any other loader, such as those illustrated in  FIG. 3 , whether in a manual loader or in an automated loader arrangement. 
         [0062]    Moving to state B, the punch  410  has been inserted through the loading port of the loader  210  in order to create a guide channel  412  in the carrier  120 , which can be seen in state C with the punch  410  now removed. 
         [0063]    With a guide channel  412  in the carrier  120 , a seed may more easily inserted into the carrier  120 , such as using the injector  230  and the injection methods discussed above. 
         [0064]      FIGS. 5A and 5B  are cross-sectional views of example multi-port loaders and injectors. While these particular example loaders facilitate loading of two seeds and four seeds concurrently, respectively, carriers may include any other quantity of loading ports and injectors may include a corresponding quantity of injection channels holding seeds for injection into corresponding loading ports. 
         [0065]    Beginning with  FIG. 5A , the loader  510  includes two loading ports  512 , including loading ports  512 A and  512 B. In this embodiment the loading ports  512  each include a single tier alignment interface, but in other embodiments different alignment interfaces may be used. The injector  530  includes two injection channels  534 , including injection channel  534 A and  534 B. Each of these injection channels includes an alignment interface at the distal end  531  of the injector  530  that is configured to engage with the corresponding alignment interface  512  of loader  510 . In this embodiment, the plunger  536  includes rods  537 , including rods  537 A and  537 B, sized to substantially fill the injection channels such that movement of the plunger  536  towards the distal end  531  causes movement of both rods  537  within the corresponding injection channels  534  in order to urge the seeds  532  (e.g., seeds  532 A and  532 B) towards the distal end  531  and into the carrier  520 . 
         [0066]    As shown in  FIG. 5A , the carrier  520  is a different size and shape than the carriers discussed in previous Figures. In this embodiment, the carrier  520  is configured to contain two seeds  532  (for example, seeds  532 A and  532 B). In other embodiments, other quantities of seeds may be inserted into the carrier  520  and/or other carriers. In some embodiments, carriers, such as carrier  520  and  560  (discussed below) are configured to be resized, such as in an operating room where the carriers are inserted into a tumor bed. Thus, certain carriers are configured for cutting, tearing, or breaking, in order to achieve a desired size and/or shape for appropriate insertion and therapeutic effect for the particular application of the carrier. In some embodiments, carriers include markings indicating to a user where it is safe to cut a carrier in order to avoid impacting an inserted radioactive seed. Thus, in embodiments where multiple seeds are injected into a carrier, markings may be included on the carrier that allow a user to cut the carrier into multiple single seed carriers for insertion into the tumor bed. 
         [0067]    In  FIG. 5B , the loader  550  includes four injection ports and the injector  570  includes four injection channels, each configured to contain one or more radioactive seeds. In this embodiment, the plunger of the injector  570  is coupled to injection plates within each of the four injection channels such that movement of the plunger towards a distal end of the injector  570  causes all four seeds to move towards the distal end and then into the carrier  560  (once the injector  570  has been engaged with the alignment interfaces of the loader  550 ). 
         [0068]      FIG. 6  is a cross-sectional view of a multi-port loader  610  that is being loaded using a single channel injector  230  (as discussed above with reference to  FIG. 2 , for example). At state A of  FIG. 6 , a carrier  620  has been placed in a loading bed of the loader  610 , such as may be performed by a manufacturer of the loader  610  so that the carrier  620  is preloaded in the loading bed of the loader  610 , or by the entity that injects the seeds into the carrier  620 . The injector  230  is loaded with the seed and the seed is injected into a first port  612 A of the loader  610  so that the seed is contained within the carrier  620 , as shown in state B. 
         [0069]    With the first seed in place within the carrier  620  (state B), the injector  230  can be reloaded with another seed and injected into a second loading port  612 B of the loader  610 . Similarly, with the second seed embedded in the carrier  620 , as shown in state C, a third seed may be loaded in the same injector  230  and injected into the carrier via port  612 C. While not shown, a fourth seed can also be loaded into the injector  230  and inserted into the carrier via port  612 D. Such an iterative loading process can be performed with loaders having any number of loading ports and injectors having any number of injection channels and seeds. For example, a dual channel injector  530  ( FIG. 5 ) may be used with the loader  610  to load two seeds into the carrier  620  concurrently, so that the process can be performed twice in order to load four seeds into the carrier. 
         [0070]      FIG. 7  is a cross-sectional view of loader  710  and a carrier  720  during a process of loading the loader  710  with a carrier  720 . In this example, the loader  710  is a four port loader, the loading bed  705  is rectangular, and the carrier  720  is similarly rectangular with a size substantially the same as the loading bed  705 . However, in other embodiments the loading methods discussed herein may be used with any other loaders, loading beds, carriers, etc. 
         [0071]    At state A, the loader  710  and carrier  720  are separate devices, which may be manufactured separately, purchased from separate entities, or manufactured and/or purchased from a single entity. The loading bed  705  is configured to engage with the carrier  720  in order to maintain a position of the carrier  720  within the loading bed  705 . Various mechanisms may be used in the loading bed  705  in order to achieve stability of the carrier  720  therein. For example, the loading bed  705  may be sized to tightly fit the carrier  720  therein. In other embodiments, the loader  710  may include a lid that attaches to a top of the loader  710  and holds a top surface of the carrier  720  in place within the loading bed  705 . In some embodiments the loader  710  includes a lid having a loading bed insert sized to fit within outer walls of the loading bed  705  and engage a top surface of the carrier  722  to more securely hold the carrier  720  in position within the loading bed  705 . Various configurations and examples of loading beds are discussed in the co-owned patent noted above with reference to the definition of Loader. All such configurations and examples of loading beds and loader functionality is hereby incorporated by reference for all purposes. 
         [0072]    Moving to state B, the carrier  720  has been placed into the loading bed  705 . Depending on the embodiment, the carrier  720  may be manually placed into the loading bed  705 . For example, a lid may be removed from a top of the loader  710  in order to expose the loading bed  705 , the carrier  720  can then be manually placed into the loading bed, and then the lid can be replaced in order to further hold the carrier  720  within the loading bed  705  and/or to provide shielding against radiation from seeds once they are inserted into the carrier  720 . In another embodiment, the loader  710  includes a slot through which the carrier  720  can be inserted, similar to how a VHS tape can be inserted into a VCR. In other embodiments, the carrier  720  can be loaded in any other manner. With the carrier  720  held in place within the loading bed  705 , the carrier is now set to receive one or more seeds via an injector. 
         [0073]      FIG. 8  is a cross-sectional view of the same loader  710 , including loading bed  705 , as illustrated in  FIG. 7 , but now the loading bed  705  loaded with a carrier cartridge  820  that holds multiple carriers in place. The example carrier cartridge  820  comprises a hard outer shell  824  and a material  822  that is dense enough to hold the multiple circular carriers  830  in predetermined positions within the carrier cartridge  820 . The shell  824  may be made of plastic, metal, or any other substance that maintains the shape of the carrier cartridge  820 . The shell  824  and/or the carrier cartridge  820  may be formed of one or more of polyethylene, high density polyethylene, borated polyethylene, polyetherimide resin, polyurethane, polytetrafluorethylene, polyehtylene terephthalate, and/or any other suitable material. 
         [0074]    In one embodiment, the shell  824  comprises a shielding material, such as a high z material, that provides radioactive shielding from seeds that are placed in carriers within the carrier cartridge  820 . In some embodiments carrier cartridge  820  does not include a separate shell  824  material; rather, the outer surface of the carrier cartridge  820  is defined by the material  822 . Thus, the carrier cartridge  820  may be molded (or formed by another manufacturing processing) in a single molding process. 
         [0075]    In the example of  FIG. 8 , the circular carriers  830  are maintained in precise positions so that when the carrier cartridge  820  is loaded in the loading bed  705  and radioactive seeds are injected into the loader  710  via the multiple loading ports, the seeds are directed into a precise area of the respective carriers  830 . For example, the carrier cartridge  820  may be configured to hold the carriers  830  such that the radioactive seeds are positioned in a center of the carriers  830 . Depending on the embodiment, the carriers  830  may be positioned in various configurations within the carrier cartridge  820  in order to achieve various placements of seeds within the carriers. For example, some of the previous patents of the current assignee listed above with reference to the definition of Carrier include details regarding offset spacing of seeds within carriers, such as so a seed can be placed closer to a top surface of the carrier than to a bottom surface of the carrier (e.g.,  1 mm from a top surface of a  4 mm thick carrier). In such an embodiment, the carrier can be placed in the tumor bed with the seed closer to the treatment area or, alternatively, that same carrier can be flipped over so that the seed is further from the treatment area if reduced radiation to the particular treatment area is desired. Placement, orientation, seed strength, and/or other characteristics related to a radiation therapy protocol may be determined manually or via one or more automated processes, such as the processes described in co-pending provisional application No. 62/113,252, filed Feb. 6, 2015, and titled “Implant Planning System And Implant Placement Guide System,” which is hereby incorporated by reference in its entirety for all purposes. 
         [0076]    At state B in  FIG. 8 , the carrier cartridge  820  has been loaded into the loader  710 , and is ready for insertion of seeds into the carriers  830  using any suitable injector, such as those discussed above and/or any other injector. 
         [0077]    Depending on the embodiment, the carrier cartridge  820  may be reusable or a single use cartridge. For example, a single use carrier cartridge may require removal of a portion of the carrier cartridge  802 , such as by unsnapping, using break-away detents, or other mechanism by which the cartridge  820  is held together, such that the carriers  830  may be removed from the cartridge  820  after seed injection. In such an embodiment, the carriers  830  may be sterilely manufactured within the carrier cartridge  820  such that a user of the carriers  830  is not required to load the circular carriers  830  into the carrier cartridge  820 . For example, a collagen manufacture that produces collagen carriers may place the carriers in a carrier cartridge  820  and seal the carrier cartridge  820  in a sterile environment for shipping to an end user. In other embodiments, the carrier cartridge  820  includes wells or slots wherein carriers can be interchangeably placed therein, loaded with seeds, and removed. In such an embodiment, the carrier cartridge  820  may be reused indefinitely. Such a carrier cartridge is discussed below with reference to  FIG. 10 . 
         [0078]    In some embodiments, a carrier cartridge may include a gridded pattern or other feature to allow a radiograph to be taken after seed loading, so seed positions can be confirmed. In some embodiments, a punch is used to create a guide channel through the shell  824  of the carrier cartridge  820 , the carrier material  822 , and/or the carrier  830  itself in order allow easier insertion of the seed from outside the carrier cartridge  820  into the carrier. For example, a single punch tool may be configured to penetrate each of these materials to create a guide channel for seed placement. 
         [0079]      FIG. 9  illustrates three additional example carrier cartridges  920 ,  930 , and  940 . As with carrier cartridge  820 , each of these carrier cartridges may be preloaded with carriers, or may include wells, slots, or other openings where carriers can be loaded into the cartridge. As shown in  FIG. 9 , the carrier cartridge  920  is loaded with four star shaped carriers, the carrier cartridge  930  is loaded with four rectangular shaped carriers, and the carrier cartridge  940  is loaded with four Gore shaped carriers. 
         [0080]      FIG. 10  is a cross-sectional view of a loader  1010  having a loading bed that includes wells  1007  sized to receive circular carriers  1030 . In this embodiment, the wells  1007  may be integrally formed as part of the loader  1010 , such that the wells  1007  are positioned at precise locations to maintain carriers at the desired location for seed injection. In another embodiment, the wells are part of a carrier cartridge that is pre-inserted into the loader  1010  prior to insertion of carriers into the wells of the carrier cartridge. For example, the carrier cartridge may be an integral part of a loader. In one embodiment, the carrier cartridge includes a channel from each of the injection ports to the wells  1007  sized and configured to allow a seed to be injected through the carrier material  1022 . In other embodiments, a punch may be used to create guide channels through the carrier material, and into the carriers in some embodiments. In other embodiments, the carrier material  1022  is configured to allow a seed to move through the carrier material  1022  into the carrier without a pre-created channel. 
         [0081]    As shown at state B in  FIG. 10 , each of the carriers  1030  has been inserted into a corresponding well  1007  of the loader  1010 . The carriers  1030  may be inserted manually, such as by a user&#39;s hands, tweezers, pliers, etc. placing each of the circular carriers into wells one at a time, or the process may be automated by a device that places the circular carriers  1030  into the wells  1007 . 
         [0082]      FIG. 11  illustrates an example use case of the loader and injector systems discussed herein. In the example of  FIG. 11 , exposure to radiation by one or more individuals that load the carrier(s) with radioactive seeds is reduced by pre-packaging of components used in the process by suppliers of the loader and/or the injector. Thus, rather than pre-inserting seeds into carriers (e.g., creating hot carriers) before they are inserted into a body (e.g., creating hot carriers by a manufacture prior to shipping), it may be advantageous to provide components that allow easy injection of seeds into carriers just prior to the expected implantation of the carriers, while also reducing risk of excessive radiation exposure to the user that loads the carriers. 
         [0083]    Separation of the carriers from seeds until time of application may provide one or more advantages. For example, the usable life of a carrier (e.g., collagen) compared to seeds may be vastly different. Seeds are typically configured for use (e.g., insertion into a tumor bed for delivery of radiation) within 5-10 days (or less) from manufacture. Collagen, however, may be useful for two years or more without appreciable deterioration in properties. Because both seeds and carriers are expensive, once they are combined into a hot carrier, the effective life of the hot carrier begins to elapse and if not used within the determined useful time frame of the seed, the combination of both seed and carrier becomes useless. Thus, use of the loading systems and methods discussed herein provide a “just in time” solution for combining seeds with carriers to minimize waste of pre-loaded hot carriers. Loading of seeds using the systems and methods discussed herein may take place at various locations and may be performed by various personnel. For example, loading can take place at the location where seeds are made (e.g., “hot carriers” may be made to order for a particular patient and dosimetry plan), with pre-packaged collagen (again, long shelf life) being combined with seeds, and shipped (e.g., overnight by a common carrier, such as FedEx) to point of use (e.g., an operating room). Alternatively, a variety of “cold” carriers and/or carrier cartridges could be stocked at the hospital, like any other sterile semi-durable supply (e.g., such as I.V. catheters). Seeds may then be pre-ordered and accessible to the operating room. For example, an expected supply of seeds (e.g., of varying radioactivity levels, sizes, shapes, etc.) may be kept on hand at the hospital and usable on demand. Thus, when an operation takes place and a tumor bed is assessed, a dosimetry may be planned (and/or confirmed from prior planning) and seeds loaded into one or more carriers (e.g., tiles, gores, stars, or a combination as suits the need). In this implementation, if not used within the usable lifetime, seeds may be wasted components, but collagen typically will not be wasted because of its longer useful lifespan. 
         [0084]    In  FIG. 11 , a sealed packaging  1110 , such as from a first supplier, may be purchased and received by an end user, such as a surgeon that is implementing a radiation treatment plan after a tumor removal surgery has been performed on a patient. In this example, the sealed packaging includes a loader  1112  that is preloaded with a carrier cartridge having one or more carriers therein. Thus, the surgeon (or other user) is not required to load carriers into the loader. In some embodiments, the loader may be preloaded with a single carrier, or the loader may be shipped along with a carrier cartridge preloaded with carriers that can be placed in the loading bed of the loader  1112  by the end user. 
         [0085]    In this example, sealed packaging  1120  contains an injection device  1122  that is preloaded with radioactive seeds configured for injection into the carriers within the loader  1112 . In this example, the loader  1112  includes four loading ports and the injection device  1122  includes four injection channels that are visible in the cross section views at the bottom of  FIG. 11 . As discussed above, the injector  1122  may be engaged with the loader  1112  via the alignment interfaces on each device, and the seeds may be injected into the carriers by pressing the plunger towards the loader  1112  in order to inject multiple (four in this example) seeds into the carriers concurrently. Once the carriers become “hot”, having seeds loaded therein, the carriers may be removed from the loader  1112  in various manners, such as by removing a lid (not shown; see related “loader” patent noted in definition section for examples of lids) of the loader  1112 . 
         [0086]      FIG. 12  illustrates an injector  1230  that includes a loading port for loading seeds into the injection channel. As discussed in some of the embodiments above, the seed may be placed in the injection channel at the distal end of the injector. In other embodiments, seeds may be loaded in other manners, such as those discussed below. 
         [0087]    The top illustration of injector  1230  is an example external view of the injector  1230 , while the remaining three illustrations are cross-sections of the same injector  1230  that illustrate operation of the injector  1230 . In particular, at state A the injector  1230  has not yet been loaded with the seed  1232 . The injector  1230  includes components similar to those discussed in various other embodiments, including an injection channel  1234 , a plunger  1236  (having a uniformly sized rod  1237  in this example, but could include a smaller rod and a plate in other embodiments), and a distal end  1231  that includes an alignment interface configured to engage with a similar alignment interface on a loader. In this embodiment, however, the injector  1230  includes a loading port  1233 , such as an opening in the injection cylinder sized to allow a seed  1232  to pass from outside the injector  1230  into the injection channel  1234 . In one embodiment, the loading port  1233  is sized horizontally and/or vertically to the precise dimensions of the seed intended for use in that particular injector  1230 , such that, for example, seeds that are too big for the injector may not be inserted (and potentially jam the injector) and seeds that are too small may be identified prior to or as they are placed into the loading port  1233  in response to a user identifying that the seed does not fit tightly within the size constraints of the loading port  1233 . 
         [0088]    At state B, the seed  1232  has been moved through the loading port  1233  and is in the injection channel  1234 . With the seed in the injection channel  1234 , the plunger  1236  may be moved towards the distal end  1231  in order to urge the seed  1232  out of the injection channel  1234  into a carrier. 
         [0089]      FIG. 13  is a diagram illustrating an example external view of an injector with a magazine port, and a seed magazine configured for attachment to the injector via the magazine port. In this embodiment, the injector  1330  includes a magazine port  1335  that fixedly receives the seed magazine  1350  so that the seed magazine  1350  can access the injection channel of the injector  1330  via the loading port  1333 . As shown in the lower illustration in  FIG. 13 , the seed magazine  1350  has been fixedly attached to the injector  1330  and, in this configuration, the injector  1330  may be used to inject multiple seeds (e.g. a quantity defined by how many seeds are in the seed magazine  1350 ) without manual loading of each seed into the injector  1330  separately. 
         [0090]    In this embodiment, the magazine port  1335  comprises a locking mechanism, such as a mechanism that might be found on a gun for receiving and attaching an ammunition clip thereto, which secures the seed magazine  1350  onto the injector  1330  while the injector  1330  is in use. Once the seeds from the seed magazine  1350  have all been injected into carriers by the injector  1330 , the seed magazine  1350  may be removed and replaced with another seed magazine having seeds loaded therein. In some embodiments, the seed magazine  1350  is reloadable, such that an empty seed magazine  1350  may be loaded by a technician, or an automated machine, by pushing seeds into the seed magazine  1350 . This reloading process may be similar to the process of loading an ammunition clip with rounds of ammunition. 
         [0091]      FIG. 14  illustrates a cross-sectional view of injector  1330  in various states as a seed magazine  1350  is used to move seeds  1332  into the injection channel  1334  one at a time for injection into a carrier. As shown at state A, the seed magazine  1350  includes a force providing source, such as a spring  1338 , that pushes seeds downward towards the loading port  1333  of the injector  1330 , and then into the injection channel  1334 . While a spring  1330  is shown in  FIG. 14 , any other component that provides a force against the seeds towards the loading port  1333  may be used. 
         [0092]    Moving to state B, the plunger  1336  has been moved towards the distal end  1331  in order to move the seed out of the injection channel  1334  (and into a carrier preferably). At state C, the plunger  1336  is then moved away from the distal end  1331  and as it moves past the loading port  1333 , the force applied by the spring  1338  causes a next seed to enter the injection channel  1334  via the loading port  1333 . Thus, at state D the next seed is in the injection channel  1334 , ready for implantation into a carrier by movement of the plunger  1336  towards the distal end  1331 . This process (e.g. moving the plunger forward to inject seeds into carriers and then pulling the plunger back to allow a next seed to be forced into the injection channel by the spring  1338 ) may be repeated until all of the seeds in the seed magazine  1350  have been injected or the desired number of seeds is used, even if seeds remain in the magazine. As noted above, the seed magazine  1350  may be replaceable, such that it can be removed and replaced with another seed magazine  1350  in order to inject additional seeds using the same plunger  1336 . In other embodiments, the seed magazine  1350  is integrally attached to the plunger  1336 , such that when the seeds are all injected, the seed magazine  1350  cannot be refilled. Such a one-time use (where one-time use includes injection of multiple seeds that are in the seed magazine  1350 ) may advantageously limit exposure to radiation by a user that could otherwise be absorbed when the seed magazine  1350  is handled, attached to the injector  1330 , and/or removed from the injector  1330 . 
         [0093]    In other embodiments, other mechanisms for loading multiple seeds into a single injection channel, such as one after another as they are inserted into different carriers or areas of a carrier, may be used. For example, a rotating multi-chamber loader, such as a revolving chamber of a revolver gun or a multi-color ball point pen, may be attached to the injector and rotated to alternate the position of the rotating loader in order to select chambers of the loader to align with the injection channel. In this way, such a rotating multi-chamber loader may be loaded (e.g., pre-loaded by a manufacturer and/or loaded by a user performing the seed injection) with multiple seeds (e.g., one seed per chamber of a multi-chamber loader, such as a loader having 3, 4, 5, 6, 7, 8, 9, 10, or any other number of rotatable loading chambers) so that the injections can be “re-loaded” with another seed simply by rotating the multi-chamber loader. 
         [0094]      FIG. 15A  illustrates an example “auto loader” that automates much of the process of loading seeds into carriers. In this example, the auto loader  1510  includes a carrier cartridge port  1506 , a seed magazine port  1504 , and an injection button  1502 . In operation, a user can place a carrier cartridge into the port  1506 , a seed magazine into the port  1504 , and then simply press the injection button  1502  in order for the auto loader  1510  to inject the seeds into the carriers within the carrier cartridge, without further human involvement. The user can then remove the carrier cartridge from the port  1506  and access the hot carriers (loaded with radioactive seeds) for use in radiotherapy treatment of a patient, for example. 
         [0095]    Depending on the embodiment, the auto loader  1510  may perform the seed insertion in many manners. In one embodiment, the auto loader  1510  comprises electromechanical parts, such as one or more servomotors that are arranged to extend in a similar manner as the plungers discussed with reference to other embodiments above in order to push seeds contained in the seed magazine into carriers within the carrier cartridge. Depending on the embodiment, the seed magazine may take on different forms. In one embodiment the seed magazine comprises a series of seeds each having access to an exit port (e.g., such as by breaking a perforation that holds the seeds in the magazine prior to insertion into the auto loader  1510 , but that is easily broken when the seeds are pressed outward) that are aligned with the ports of the carrier cartridge such that seeds can be pressed directly out of the seed magazine into the appropriate ports of the carrier cartridge and further into the appropriate locations within the carriers. Thus, in one embodiment the carrier cartridge and seed magazine are paired, such that the positions of carriers within the carrier cartridge matches the spacing of seeds within the seed magazine. 
         [0096]      FIG. 15B  illustrates another example autoloader  1511 , including a cross-sectional view of the loading bed. In this embodiment, the loading bed that receives the carrier cartridge is adjustable, such that different sizes, shapes, and/or orientations of carrier cartridges and/or carriers can be held securely in the loading bed. In the example illustrated, an adjustable member  1512  is included in the loading bed such that the user can slide the member back and forth within the loading bed in order to decrease an effective size of the loading bed and more tightly contain a smaller carrier cartridge and/or carrier. In other embodiments, a similar adjustable member may be included on the orthogonal dimension, such that the carrier cartridge may be tightly contained on all sides. 
         [0097]    In this embodiment, the auto loader  1511  includes four sliders  1514  that are movable by a user to indicate positions of carriers within the loading bed and/or positions in which seeds should be inserted into the carrier(s) within the loading bed. In one embodiment, for example, the sliders are attached to respective loading channels that extends between the seed magazine and the loading bed, such that movement of the sliders adjusts a loading channel through which seeds are pushed when the injection button is pressed and the electromechanical components within the auto loader  1511  are activated. In this way, custom seed loading patterns could be generated within a single carrier, such as seeds that are placed asymmetrically within a carrier. Additionally, each of the loading channels may be set to deliver different seeds (e.g., different radioactivity, sizes, etc.) and/or different quantities of seeds to a particular carrier. For example, the auto loader  1511  may be set to deliver three seeds in a first channel, two seeds in a second channel, one seed in a third channel, and no seeds in a fourth channel. 
         [0098]      FIG. 16  illustrates a top and a front view of an auto loader  1610 . In this embodiment, a seed magazine is inserted on a top of the auto loader  1610 , and the carrier cartridge is inserted on the front of the auto loader  1610 . In this embodiment, the carrier cartridge and seed magazine may engage one another when fully inserted, as each is supported by a separate portion of the auto loader  1610  frame. Thus, alignment of seeds within the magazine and loading ports within the carrier cartridge may be more precise. 
         [0099]      FIG. 17  illustrates example components that are usable in an automated process of loading seeds into carriers. In this particular example, a carrier placement system  1710  includes one or more electronic and/or mechanical components that deliver carriers to a conveyor belt, such as the vertically oriented conveyor belt system illustrated in  FIG. 17 . In this example, the conveyor belt includes multiple supports  1723  that are each sized to support a carrier  1724  as it is received from the carrier placement system  1710 . In this example, the conveyor belt moves in a clockwise direction, such that the carriers  1724  are placed on supports  1723  near a top of the system and then are moved down as the conveyor belt and supports  1723  are moved downward. In other embodiments, configurations of automated systems for delivery of carriers may be performed by any known or later developed robotics and/or manufacturing processes. In this example, the conveyor belt moves the carriers  1724  downward towards a seed injection system  1720  that includes electromechanical components configured to operate a seed injector  1722  in order to inject a seed (or multiple seeds in some embodiments) into each of the carriers  1724 . In the example illustrated, the seed injector  1722  operates in a similar manner as the injectors discussed above, such as by a plunger being moved through an injection channel in order to force a seed out of the injector  1722  and into an adjacent carrier  1724 . 
         [0100]    In one embodiment, the conveyor belt stops momentarily when a carrier is positioned to be loaded with the seed. This pausing may be performed based on an expected uniform spacing of supports  1723  on the conveyor belt or may be performed in response to optical and/or mechanical components sensing that a carrier is in the appropriate position for seed injection. 
         [0101]    In the embodiment illustrated, the seed injector  1722  may be reloaded with seeds using automated loading components such as those discussed above with reference to  FIG. 14 , for example. 
         [0102]      FIG. 18  illustrates another seed injection system  1820  that may be used in place of the seed injection system  1720  of  FIG. 17  and/or in any other automated seed injection embodiment. In this example, the seed injection system  1820  includes the same or similar seed injector  1722 , but also includes a guide path creation tool  1802  that is configured to move left to right (in this particular implementation) in order to puncture each carrier at a precise location where the seed injector  1722  will later insert the seed into the carrier. The guide path creation tool  1802  creates a guide path that allows the seed to more easily be inserted into the carrier material. With use of a guide path creation tool  1802 , rectangular shaped seeds may be more reliably inserted into carriers using this automated process, minimizing damage to the seed and carrier material. In other embodiments, the carriers may have a guide path pre-punched such that the seed injection system does not need to create the guide path. 
       Other Embodiments 
       [0103]    Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. 
         [0104]    It should be emphasized that many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure. The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the invention can be practiced in many ways. As is also stated above, the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to including any specific characteristics of the features or aspects of the invention with which that terminology is associated. The scope of the invention should therefore be construed in accordance with the appended claims and any equivalents thereof.