Patent Publication Number: US-2015082614-A1

Title: Brachytherapy appliance and method

Description:
This application is a division of co-pending U.S. patent application Ser. No. 12/812,851, filed Jul. 14, 2010, which application was submitted under 35 U.S.C. 371 claiming priority to PCT/US2008/00472, filed Jan. 14, 2008. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to an appliance removably positionable on or against a surface of a living body, such as the body of a human or animal, for positioning a therapeutic delivery device in a desired precise location in relation to a selected portion of the body in or adjacent to the surface and containing a cancer, tumor, or other diseased tissue, for delivering a therapy, particularly radiation, to the diseased tissue, and a method of making the appliance so as to conform to the body surface, based on a computerized three dimensional model or map generated from a scan of the body region, the appliance being particularly adapted for use in a body cavity such as the oral cavity. 
     BACKGROUND ART 
     The disclosures of co-pending patent application Ser. No. 12/812,851, filed Jul. 14, 2010, and PCT application Serial No. PCT/US2008/00472, filed Jan. 14, 2008, are hereby incorporated herein in their entirety by reference. 
     In the field of medicine, there are courses of treatment for diseases and injuries which are facilitated by placement of a therapeutic device within a body cavity, in a particular relation to a selected, or a predetermined, region thereof, or adjacent tissue, for delivering a therapeutic dosage. For instance, in oncology, particularly for the treatment of mouth and/or throat cancers, and more generally cancers of the head and/or throat, breast and prostate, and also non-cancerous diseases, such as non-malignant tumors and neuromas, therapeutic benefit has been achieved by brachytherapy, that is, the placement of radioactive elements, also referred to as radioactive seeds, in proximity to, or surgically directly in the cancer or cancerous or other diseased tissue, for directing radiation thereat. However, a side effect that has been observed is relatively uncontrolled irradiation of the surrounding tissue and/or organs. Specifically in this regard in relation to cancers and other diseases of the neck, head and mouth, is injury to and loss of teeth, and injury to salivary and other glands such as those relating to the sense of taste and smell, which is undesirable for many reasons. 
     It is thus sought to provide an appliance configured and/or adapted for placement in conforming relation to a body surface, with particular utility for use in cooperation with a surface within a body cavity, such as, but not limited to, the oral cavity, which allows removably or temporarily positioning of one or more therapy delivery elements, particularly radiation emitting elements, such as radioactive seeds, wires or the like, in precise relation to a cancer or other diseased tissue in or adjacent to the surface, which provides shielding for other regions of healthy tissue, glands and/or organs, as well as teeth, from the radiation emitted by the radioactive element or elements. Further in this regard, it would be advantageous to provide an appliance custom configured to conform to the shapes and contours of the body surface, so as to be positionable and automatically retained thereagainst in conforming relation thereto in a selected precise location and orientation in relation to the tissue which is to be irradiated, while providing radiation shielding for the other tissue and organs not intended to be irradiated. In such appliance, it would be advantageous to provide at least one receptacle or passage into which a therapeutic device, such as a seed or seeds, or a wire having a radioactive tip or other region, or other radioactive medium, is removably insertable, so as to be positioned for delivery of a radioactive dose in precise relation to a cancer to be irradiated for a specific time or specific therapeutic dosage. 
     SUMMARY OF THE INVENTION 
     According to the invention, a brachytherapy appliance and method of practicing the same, which overcomes one or more of the problems and/or shortcomings, and provides one or more of the advantages set forth above, is disclosed. 
     According to a preferred aspect of the invention, a brachytherapy appliance is provided including a body portion fabricated to conform to contours of a body surface, which can be a surface within the oral cavity The appliance is positionable in close proximity to or against the body surface so as to be retained thereagainst or thereon, the body portion including at least one receptacle or passage disposed in or extending through a portion thereof adapted for receiving and holding a therapeutic element in precise relation to a cancer or cancerous tissue in the cavity or in nearby tissue, and which optionally includes shielding for protecting other tissue and body portions from the therapeutic element or effects thereof, particularly radiation therefrom. A therapeutic element is removably insertable in the body portion receptacle or passage in a predetermined position and/or orientation for delivering a therapeutic treatment, e.g., radiation, toward the cancer or cancerous tissue. Examples of a therapeutic element include, but are not limited to, a radiation delivery element such as a wire including a radiation emitting or irradiated portion, such as a tip or other segment, or one or more radiation emitting seeds, or other radioactive media. By providing the therapeutic, e.g. radioactive, media separately of the body portion, advantages include that the number and dosing, e.g., radioactivity, of the radioactive media can be varied, for instance, to allow changing the radiation dose or time of dosage over the course of therapy, or otherwise. This also allows use of the same radioactive media with more than one appliance, and also facilitates handling and storage of the radioactive media, and safe disposal of the non-radioactive body portion. 
     According to another preferred aspect of the invention, the body portion is configured or custom fit to fit securely on the upper teeth in the oral cavity, if any, or to the upper edentulous arch, such as by molding, so as to be positioned in the superior region of the oral cavity. The body portion is fabricated from a suitable polymeric material, such as, but not limited to, a suitable well known, commercially available moldable dental acrylic, such as, but not limited to, a methyl methacrylate. The at least one receptacle or passage will be molded into the body portion, and will comprise a tube or catheter adapted for receiving the radiation emitting media, such as a wire, therein, the tube or catheter being routed so as to have a portion or opening positioned to be disposed in desired relation to the cancer when the body portion is properly positioned in the body cavity, for delivery of the desired therapy, i.e., irradiation and destruction of the cancerous or diseased tissue or cells. The body portion additionally may include one or more layers of shielding material embedded therein, such as a lead shielding material, positioned for shielding adjacent healthy tissue, organs, teeth, or other vulnerable body parts, from radiation emitted by a radioactive region or portion of a wire or other radiation emitting media inserted into the tube or catheter. The lead shielding material, in turn, is incorporated into the body portion such that when the body portion is positioned in the oral cavity, the lead material will not contact the adjacent tissue, nor will the lead material be exposed to saliva or other fluids present in the cavity, which could carry contaminants to the surrounding tissue. It is also contemplated that an appliance of the invention can be configured for fitting in other regions of the oral cavity, such as on the lower teeth and/or edentulous arch, for treatment of cancers or diseases in the vicinity thereof. 
     According to still another preferred aspect of the invention, the therapeutic media comprises a wire removably insertable into the tube or catheter, and can be, for instance, a stainless steel wire, and can be, for instance, tipped with iridium  192 , or another suitable radioactive substance. The wire is of a suitable length so as to extend through the tube or catheter so as to position the irradiated portion in the desired location in relation to the cancer or other diseased tissue, hereinafter sometimes referred to as “the cancer”, with the opposite end of the wire protruding from the appliance, and more preferably, also from the body cavity so as to be graspable for insertion and removal from the appliance. The wire can also include indicia along the length thereof for indicating proper placement of the tip or other irradiated portion at the desired location within the appliance, and thus in relation to the cancer to be irradiated. 
     According to a further preferred aspect of the invention, the body portion of the appliance will include multiple ones of the tubes or catheters, as required for holding the media necessary for treating, e.g., irradiating, the cancer to the desired extent. As an example, a plurality of the tubes or catheters will be arranged in a required array, such as, a linear, side-by-side array, for providing a desired pattern and/or dose of therapy, e.g., radiation, to the cancer. 
     The required location of the tubes or catheters within the body portion of the appliance will be determined by the location of the cancer or diseased tissue, as found using common techniques, such as CT scanning or the like. The duration and/or dosage of treatment will be determined by an oncology professional or physicist. 
     According to a still further preferred aspect of the invention, a method of use of the appliance will include steps of molding the body portion to a surface region of a body, e.g., within a body cavity, such as the oral cavity, including installing the shielding, if used, and the at least one tube or catheter in the respective locations for holding the media for providing the therapeutic dosing to the cancer. The radioactive wire or wires or other media are then inserted into the one or more catheters or tubes, respectively, to position the therapeutic element or elements, e.g., radioactive seed or tip, in the desired relation to the cancer or diseased tissue. The appliance will then be left in place for the period of time necessary for delivery of the determined therapeutic dose to the cancer or diseased tissue. The wire or wires are then removed from the appliance, and the appliance removed from the subject body surface. 
     According to still another preferred aspect of the invention, a method of making the brachytherapy appliance involves utilizing a suitable three dimensional computer-generated model or rendering of a portion of a body against which, or adjacent to which, the appliance is to be located. The computer model can be generated using a suitable scanning device capable of modeling or mapping a body surface, such as, but not limited to, a CT scanning device such as a conventional multi-slice CT (MDCT) scanner, or a dental (cone-beam) CT scanner, or an MRI scanner. From this model, the topography (shape) of the surface of the body against which, or adjacent to which, the appliance is to be located, will be ascertained. This can include both soft (e.g., soft tissue) and hard (e.g., tooth) surfaces, and can be developed using known surface discernment and mapping techniques. A three dimensional physical model of this surface will then be produced. This three dimensional physical model can be of the body surface against which, or adjacent to which, the appliance is to be placed, and to which the appliance will be molded or conformed, or it can be the surface of the appliance that will be placed against, or adjacent to, the body surface, so as to essentially be a mirror image of, or mate to, that surface. The physical model can be produced, for instance, using a commercially available computer controlled lithography process, such as by solidifying liquid photopolymer into the three dimensional shape, milling a urethane or other suitable polymer block into the shape, or other three dimensional physical modeling technique used for making medical models. 
     If the physical model is of the body surface, the appliance can be made in any suitable manner, by molding or conforming the appliance to that surface, including in any of the above described ways, for instance by molding the appliance to the physical model, wherein the catheter or catheters are positioned on the model and are held in place using wax or adhesives. Also, the catheter or catheters can be set a required or desired distance from the surface of the physical model. Shielding can be applied as required or directed. Then, a vacuum form plastic shell can be sucked down on the model and catheter or catheters, and shielding, if present, to form the appliance. The formed plastic shell is then trimmed if required and the appliance is complete. 
     If the physical model is to be of the appliance itself, according to one preferred aspect of the invention, the initial conforming layer is produced, to provide a base for positioning the catheter or catheters, using any of the techniques discussed above, such as the lithographic technique. The catheter or catheters, and shielding if required, are then added to the appliance, and the thickness of the appliance can be increased, if required, using an appropriate method, such as using layers of plastics material. As an alternative, the body of the appliance can be produced, including one or more passages therein which will serve as the catheter or catheters, or for receiving the catheter or catheters, and the shielding, if required, added at an appropriate point in the fabrication process. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top view of aspects of a brachytherapy appliance according to the present invention, including a plurality of catheters for receiving radioactive tipped wires, respectively, for dosing a cancer with radiation; 
         FIG. 2  is another top view of the brachytherapy appliance, illustrating alternative locations for the catheters; 
         FIG. 3  is a side view of the brachytherapy appliance; 
         FIG. 4  is a sectional view of the brachytherapy appliance, taken along line  4 - 4  of  FIG. 3 ; 
         FIG. 4   a  is a sectional view of the appliance illustrating alternative shielding of the invention; 
         FIG. 4   b  is a top view of the appliance, illustrating another alternative shielding; 
         FIG. 4   c  is another top view of the appliance, illustrating another alternative shielding; 
         FIG. 4   d  is a fragmentary top view of the appliance, illustrating still further alternative shielding; 
         FIG. 5  is a side view of a human head including a brachytherapy appliance of the invention installed in an oral cavity of the head; 
         FIG. 5   a  is an enlarged fragmentary side view of the human head of  FIG. 5 , showing the appliance in relation to a cancer, and radiation being emitted toward the cancer; 
         FIG. 6  is a side view of aspects of another brachytherapy appliance according to the present invention, including a plurality of catheters for receiving radioactive tipped wires, respectively, for dosing a cancer with radiation; 
         FIG. 7  is a bottom view of the brachytherapy appliance of  FIG. 6 ; 
         FIG. 8  is a sectional view taken along line  8 - 8  of  FIG. 7 ; 
         FIG. 9  is another sectional view of the appliance of  FIGS. 6 and 7 , illustrated in association with teeth and a jaw in an oral cavity of a human head; 
         FIG. 10  is an illustration and a high level flow diagram, showing steps of a method of the invention for making a brachytherapy appliance; 
         FIG. 11  is a perspective view of a reservoir of liquid photopolymer, and a three-dimensional physical model of a body surface being produced by solidifying the liquid photopolymer using lasers; 
         FIG. 12  is a perspective view of a polymer block, including a three-dimensional model of a body surface to be milled from the block; 
         FIG. 13  is another perspective view of a polymer block of  FIG. 12 , illustrating a portion of the three-dimensional model milled therefrom; 
         FIG. 14  is a perspective view of a finished brachytherapy appliance that can be made using the solidified liquid photopolymer process of  FIG. 11 , or the milling process of  FIGS. 12 and 13 ; 
         FIG. 14   a  is a perspective view of another finished brachytherapy appliance that can be made using the solidified liquid photopolymer process of  FIG. 11 , or the milling process of  FIGS. 12 and 13 ; 
         FIG. 15  is sectional view taken through the appliance of  FIG. 14   a , illustrating one embodiment of channels or catheters that can be formed in the appliance as part of the lithography process of  FIG. 11 ; and 
         FIG. 16  is another sectional view of the appliance of  FIG. 14   a , illustrating another embodiment of channels, that can be formed as part of the processes of either  FIG. 11 , or  FIGS. 12 and 13 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring now to  FIGS. 1 ,  2 ,  3  and  4 , wherein like numerals refer to like parts, a brachytherapy appliance  10  constructed and operable according to the teachings of the present invention, is shown. Brachytherapy appliance  10  is configured for use in cooperation with body surfaces within an oral cavity of a living body, which, as depicted hereinafter, is a human body. It should be recognized however, that the teachings of the invention have utility for brachytherapy appliances for use in cooperation with a wide variety of surfaces of a living body. Appliance  10  generally includes a body portion  12  which will be at least generally and preferably custom molded to the contours of a region of an oral cavity of a living body. More particularly, body portion  12  is molded to conform to the upper regions or palate of a human oral cavity, including a center region  14  molded to selected regions of the hard and/or the soft palate of the oral cavity, and a peripheral region  16  molded to the upper teeth, if any, and/or the endentulous ridge or arch, thereby forming a recess  18  extending partially around the center region  14 , and contoured for cooperatively receiving and releasably attaching to the upper teeth, if any, or to the edentulous ridge or arch. Body portion  12  can be molded using common dental molding techniques and commercially available polymeric materials commonly used in the same, such as a well-known, commercially available dental acrylic material such as a methyl methacrylate. Importantly, at least one therapy delivery element is incorporated into appliance  10 , which here preferably comprises at least one catheter  20  incorporated in or on body portion  12 . Each catheter  20  is preferably adapted for cooperatively receiving and positioning radioactive media in desired relation to a cancer, which media here comprises an elongate wire  22  including a radiation emitting portion, which is preferably a radioactive tip  24  of iridium  192 . Each catheter  20  is essentially a hollow tube defining a passage  26  ( FIG. 4 ) having at least a terminal end portion  28  ( FIG. 1 ) which is precisely positioned in relation to body portion  12 , such that when a wire  12  is received in passage  26  with radioactive tip  24  located in the terminal end portion  28 , tip  24  will be precisely positioned for irradiating a cancer or diseased tissue when appliance  10  is installed in the oral cavity. 
     The location, size and extent of the cancer will be determined by an oncology professional, and the radiological dosing will be determined by the oncology professional and/or physicist. From that information, the number and position of catheters  20  required will be determined by the professionals. Appliance  10  will be fabricated to include the required number of catheters  20 , in the required position or positions, such that the therapy delivering region or regions of the wire or wires inserted into the catheter or catheters will be properly disposed for delivering the contemplated radiation dose to the cancer or diseased tissue. In this embodiment, this will entail the positioning of terminal end portions  28  of the catheters  20  in, or in connection with, molded body portion  12 , such that the radioactive tips  24  of the wires when located in the catheters will be positioned for delivery of the required radiation dose to the cancer. Preferably, this will entail the fixed molding or affixing in place of catheters  20  within body portion  12 , such that terminal end portions  28  will be fixed in location with respect to the cancer or diseased tissue when appliance  10  is installed in the oral cavity. Also preferably, this will entail allowing the extension of opposite ends  30  of catheters  20  from body portion  12 , and thus also from the mouth  32  of a person  34  when appliance  10  is installed, as shown in  FIG. 5 . This will allow a healthcare professional to safely and conveniently insert wires  22  into catheters  20  with body portion  12  installed in the mouth, to position radioactive tips  24  at terminal end portions  28  within catheters  20 , for delivering the required radiation dose to a cancer or diseased tissue, such as representative cancer  36 , also illustrated in  FIG. 5 . At the end of the radiation therapy, wires  22  are removed from body portion  12 , and body portion  12  removed from the mouth. 
     As noted hereinabove, radiation emitted by a therapeutic device, such as any of radioactive tips  24  of wires  22 , can potentially unintentionally injure or damage noncancerous body parts, tissue, glands and/or organs, such as the teeth, salivary glands, olfactory nerves, taste buds, and the like. To avoid such injury or damage, appliance  10  includes one or more shields, such as a radiation shield  38  as variously illustrated in  FIGS. 4 ,  4   a ,  4   b ,  4   c  and  4   d , in association with body portion  12 , positioned or disposed for providing shielding of desired tissue regions, glands, organs, and/or other body parts, from radiation emitted by tips  24 . A shield, such as radiation shield  38 , can comprise a suitable radiation absorbing or containing material, such as lead. To protect non-diseased body portions, such as the tissue of the superior region of the oral cavity, such as the endentulous arch, the tongue, teeth, and the like, located in the vicinity of a shield, such as shield  38 , from unhealthy effects from exposure to the material of the shield, the shield is preferably encapsulated by a layer of protective material, for instance, by one or more layers of the polymeric material constituting body portion  12 , such as an acrylic or the like. A shield can be encapsulated within body portion  12  when molded, or can be installed on a surface thereof, then coated with the protective layer. Here, for instance, terminal and portions  28  of catheters  20  are disposed in the posterior region of body portion  12 , for irradiating a cancer in the posterior region of the oral cavity, or the upper throat region, as generally illustrated by cancer  36  in  FIGS. 5 and 5   a . Shield  38  for this location, can cover the inferior or lower or lateral surface of body portion  12  which will face the oral cavity, generally denoted as region  40  in  FIG. 3 , to protect the healthy tissue, as well as those portions of the upper teeth and gums that face and therefore could be injured by subjection to radiation emitted by tips  24  when installed in catheters  20  ( FIG. 5   a ), as generally denoted by regions  42  and  44  in  FIG. 4 . 
     Here, it should be noted that it is contemplated that the shielding to be used in association with a brachytherapy appliance of the invention, such as appliance  10 , can take any of a variety of forms, as desired or required for providing protection to tissue and other body parts from radiation emitted by the radioactive elements of the appliance. For instance, the shielding can take the form of an envelope ( FIGS. 4   a ,  4   b ,  4   c  and  4   d ) covering both the superior and/or inferior surfaces of catheters  20 , as well as, anterior and/or posterior shielding and lateral shielding. More particularly in this regard, it is contemplated that an appliance according to the invention could include catheters  20  which are substantially completely ensconced within radiation shielding, with the exception of one or more precisely placed and oriented windows, such as a window or windows ( FIGS. 4   b ,  4   c  and  4   d ) for the emission of radiation toward a cancer or diseased tissue. 
     Referring more particularly to  FIG. 2 , as noted above, it is also contemplated that catheters  20 , and more particularly, the terminal end portions  28  or other portions thereof which are to hold the radiation emitting elements, can be positioned at any location on or in connection with an appliance of the invention, such as appliance  10 , for facilitating delivery of the radiation dose required for treatment of a cancer. This is denoted by numerals  28 A,  28 B,  28 C and  28 D, which illustrate alternative locations for terminal and portions  28 , both in the anterior/posterior and lateral directions. 
     Still further, it is contemplated according to the invention that catheters  20  can be of the same or a different length, for positioning radiation emitting portions of wires, such as tips  24  of wires  22 , in desired relation to a cancer for dosing the cancer with radiation, as illustrated in  FIGS. 4   b ,  4   c  and  4   d . For instance, terminal end portions  28  or other radiation positioning portions of a plurality of catheters  20  could be arranged in a generally circular, oval, offset, or other shaped array deemed most effective for dosing a cancer with radiation, as illustrated in  FIGS. 4   c  and  4   d . A plurality of catheters  20  can also be arranged in a three-dimensional array, again, such as deemed most effective for dosing a cancer with radiation. 
     As another feature of the invention, wires  22  and/or catheters  20  can include indicia for indicating when wires  22  are fully received within catheters  20 , respectively, for positioning the radiation emitting portions of the wires, such as radioactive tips  24 , at the desired position in relation to a cancer. For instance, such indicia can include a mark or markings along the length of a wire  22 , such as a dyed or etched spot, notch, or the like, as generally denoted by numerals  46  in  FIG. 1 , which will match up with an end  30  of a catheter  20  ( FIG. 5 ), such that when the mark or marking is coincident with, or in other predetermined relation with, end  30 , a healthcare professional inserting the wire  22  into a catheter  20  will know that the wire is properly and fully positioned within the catheter. The properly positioned wire or wires  22  will then be left in the catheter or catheters  20  for the prescribed time, and then removed when the radiation dose has been delivered. Alternatively, or additionally, a wire or wires  22  could include a hard stop, such as a sharp bend or crease at the location therealong to be coincident with the end  30  of conduit  20 , to provide the desired indication of proper positioning. 
     Referring also to  FIGS. 6 ,  7 ,  8  and  9 , another brachytherapy appliance  50  constructed and operable according to the teachings of the present invention, is shown, like parts of appliance  50  and appliance  10  being identified by like numerals. Brachytherapy appliance  50 , like appliance  10 , is configured for use in an oral cavity of a living body, which, as depicted in  FIG. 9 , is a human body. Appliance  50  generally includes a body portion  52  which will be at least generally and preferably custom molded to the contours of a region of an oral cavity of a living body. More particularly, body portion  52  is molded to conform to the lower teeth  54 , if any, and/or the lower endentulous ridge or arch, thereby forming a recess  56  contoured for cooperatively receiving and releasably attaching to the lower teeth  54 , if any, or to the lower edentulous ridge or arch. Body portion  52 , like body portion  12 , can be molded using common dental molding techniques and commercially available polymeric materials commonly used in the same, such as a well-known, commercially available dental acrylic material such as a methyl methacrylate. Importantly, at least one therapy delivery element is incorporated into appliance  50 , which here preferably comprises at least one catheter  20  incorporated in or on body portion  52 . Each catheter  20  is preferably adapted for cooperatively receiving and positioning radioactive media in desired relation to a cancer, which media here comprises an elongate wire  22  (illustrated in other Figures) including a radiation emitting portion, which is preferably a radioactive tip of iridium  192 , as explained above. Each catheter  20  is essentially a hollow tube defining a passage having at least a terminal end portion  28  which is precisely positioned in relation to body portion  52 , such that when a wire  12  is receivable in the passage with radioactive tip  24  located in the terminal end portion  28 , tip  24  will be precisely positioned for irradiating a cancer or diseased tissue when appliance  50  is installed in the oral cavity. 
     The location, size and extent of the cancer will be determined by an oncology professional, and the radiological dosing will be determined by the oncology professional and/or physicist. From that information, the number and position of catheters  20  required will be determined by the professionals. Appliance  50  will be fabricated to include the required number of catheters  20 , in the required position or positions, such that the therapy delivering region or regions of the wire or wires inserted into the catheter or catheters will be properly disposed for delivering the contemplated radiation dose to the cancer or diseased tissue. In this embodiment, this will entail the positioning of terminal end portions  28  of the catheters  20  in, or in connection with, molded body portion  52 , such that the radioactive tips  24  of the wires when located in the catheters will be positioned for delivery of the required radiation dose to the cancer. Preferably, this will entail the fixed molding in place of catheters  20  within body portion  52 , such that terminal end portions  28  will be fixed in location with respect to the cancer or diseased tissue when appliance  50  is installed in the oral cavity. Also preferably, this will entail allowing the extension of opposite ends  30  of catheters  20  from body portion  52 , and thus also from the mouth  32  of a person  34  when appliance  50  is installed, as shown in  FIG. 9 . This will allow a healthcare professional to safely and conveniently insert wires  22  into catheters  20  with body portion  52  installed in the mouth, to position radioactive tips  24  at terminal end portions  28  within catheters  20 , for delivering the required radiation dose to a cancer or diseased tissue, such as representative cancer  58 , also illustrated in  FIG. 9 . At the end of the radiation therapy, wires  22  are removed from body portion  52 , and body portion  52  removed from the mouth. 
     As noted hereinabove in relation to appliance  10 , radiation emitted by a therapeutic device, such as any of radioactive tips  24  of wires  22 , can potentially unintentionally injure or damage noncancerous body parts, tissue, glands and/or organs, such as the teeth, salivary glands, olfactory nerves, taste buds, and the like. To avoid such injury or damage, appliance  50  includes one or more shields, such as a radiation shield  38  as illustrated in  FIGS. 8 and 9 , in association with body portion  52 , positioned or disposed for providing shielding of desired tissue regions, glands, organs, and/or other body parts, from radiation emitted by tips  24 . A shield, such as radiation shield  38 , can comprise a suitable radiation absorbing or containing material, such as lead. To protect non-diseased body portions, such as the tissue of the inferior and superior regions of the oral cavity, such as the endentulous arch, the tongue, teeth, and the like, located in the vicinity of a shield, such as shield  38 , from unhealthy effects from exposure to the material of the shield, the shield is preferably encapsulated by a layer of protective material, for instance, by one or more layers of the polymeric material constituting body portion  52 , such as an acrylic or the like. A shield can be encapsulated within body portion  52  when molded, or can be installed on a surface thereof, then coated with the protective layer. Here, for instance, terminal and portions  28  of catheters  20  are disposed in the lateral region of body portion  52 , for irradiating a cancer in the cheek region of the oral cavity, as generally illustrated by cancer  58  in  FIG. 9 . Shield  38  for this location, can cover the region of body portion  52  which will face the healthy tissue to be shielded, generally denoted as region  60  in  FIG. 9 , to protect the healthy tissue, as well as those portions of the teeth and gums that face and therefore could be injured by subjection to radiation emitted by tips  24  when installed in catheters  20 . 
     Referring also to  FIGS. 10 ,  11 ,  12  and  13 , steps of additional methods according to the invention for producing a brachytherapy appliance are illustrated, and in  FIGS. 14 ,  15  and  16 , a brachytherapy appliance illustrative of those that can be made by any of such additional methods, is shown. Essentially, in the additional methods of the invention, a computerized model or map of the topography of a surface of a portion of a body against which a brachytherapy appliance is to be positioned, is developed. Referring in particular to  FIG. 10 , using a suitable scanning device capable of modeling or mapping a body surface, such as, but not limited to, a tomography device such as a CT scanning device, e.g., a conventional multi-slice CT (MDCT) scanner, a dental (cone-beam) CT scanner, or an MRI scanner, as represented by scanning device  60 , the computer model can be generated, as denoted at step  62 . X-ray data and/or data from a laser scan of the oral cavity can also or alternatively be used for developing the computerized data set. Manual interpretation and surface feature discrimination of data can also be used as required, for achieving the desired accuracy. The objective of the map is to provide a shape to which the appliance will be modeled, having sufficient detail for the purposes of the present invention, which is to position a therapeutic element or elements, e.g., radioactive tipped wire or wires, in desired position and proximity to diseased tissue, for delivering a therapeutic treatment to the tissue. 
     It is contemplated and anticipated that, as an advantage of the invention, in many instances, at least one of scan of the pertinent body region will be or have been performed as a matter of course in a diagnosis of the disease and/or determination of the location and/or extent of the diseased tissue, or for other more routine dental related purposes. It is also contemplated that such a diagnostic scan or scans will include imaging data which encompasses the surface of the body portion against which the brachytherapy appliance is sought is to be placed, which data will thus have utility for generating the surface model or map for the present purposes. Using an existing scan is advantageous for a number of reasons, including that eliminates need for a new scan and thus limits radiation exposure, which can be an important factor for patients about to receive radiation therapy, and it can eliminate a need for physically molding the body surface itself, e.g., the making of impressions. This can be particularly desirable when the patient is sickly, recovering from a surgery, and/or unable to open his or her mouth to the extent required for making an impression of the subject surface with conventional dental molding materials. This is also desirable in the event the subject surface is in a location wherein the molding operation may generate a gag reflex and/or discomfort or pain, such as more toward the rear of the oral cavity. If an existing scan is not available, one can be performed, with the advantage that it will not be as invasive as making a dental impression. 
     As still another advantage, the computerized surface map can be generated at any time subsequent to the scan or scans, and additional physical access to the patient is not required. Such mapping will include either or both soft (e.g., soft tissue) and hard (e.g., tooth) surfaces, depending on the required positioning of the appliance. 
     From the map, a three dimensional physical model of the body surface will be produced, as denoted at step  64 . This three dimensional physical model can be of the body surface against which, or adjacent to which, the appliance is to be placed, and thus to which the appliance will be molded or conformed, or it can be the surface of the appliance itself that will be placed against, or adjacent to, the body surface, that is, so as to essentially be a mirror image or mating surface to the subject body surface. The appliance is then produced, using the model, as denoted by step  66 . Here, if the three dimensional model is the mirror or mating surface to the body surface, the model will form all or a portion of the body of the appliance. 
     If the physical model is of the body surface, the appliance can be made in any suitable manner, by molding or conforming the appliance to the model, including in any of the ways described above for making appliances  10  and  50 , for instance, by molding, thermal or vacuum forming or otherwise conforming the appliance to the physical model, e.g., wherein the catheter or catheters are positioned on the model and are held in place using wax or adhesives, and set a required or desired distance from the surface of the physical model. Shielding can be applied or incorporated as required or directed by the physician or physicist, and a shell, such as a thermal form or vacuum form plastic shell, can be formed or placed on the model and catheter or catheters, and the shielding, if present, to hold them in place. The formed plastic shell is then trimmed if required and the appliance is complete. As an alternative, the catheter or catheters, or representations thereof can be located on the physical model, and the appliance molded or formed thereover, for incorporating the catheter or catheters into the appliance. 
     If the three-dimensional physical model is of the appliance side of the surface, the model can be formed so as to comprise essentially the complete appliance, or just the portion or layer thereof which will be placed against, or adjacent to, the subject body surface. In either instance, the computerized map can be adapted to also include locations for an element or elements to serve as, or to receive, the catheter or catheters, for instance, one or more grooves and/or fully or partially enclosed channels, positioned and routed as determined by the oncology professional or physicist. This is illustrated in  FIGS. 15 and 16  discussed below. Additional features, such as the surface shape and contours of the opposite side of the appliance can be incorporated into the model. 
     Referring more particularly to  FIG. 11 , the physical model can be produced, for instance, using a commercially available computer controlled lithography process, such as a stereo lithography process wherein a liquid photopolymer  68  contained in a reservoir  70  is selectively cured into a three dimensional model  72 , using beams emitted from appropriate light or radiation sources  74  and  76  based on the map data. The light or radiation sources can comprise, for instance, but are not limited to, lasers or ultraviolet lights. Essentially, this process relies on precisely controlled relative movements of the polymer reservoir and light or radiation beams, as denoted by arrows  78 , for the selective curing of the polymer at the intersection  80  of the beams, as controlled by a computer based on the three dimensional map data. 
     Referring more particularly to  FIGS. 12 and 13 , the physical model  72  can also be produced by computer controlled milling machine, from a urethane or other suitable polymer block  82 . As in the stereo lithography process, the computer will control the milling operation based on the three dimensional map data to produce the replica of the body surface, the milling cutter  84  and block  82  being relatively precisely movable, as denoted by arrows  76 , for forming model  72 . Again, this surface can be the body surface itself, as illustrated in  FIG. 13 , or the mirror image or mating surface that forms part of the appliance. In the latter instance, the dotted lines of model  72  illustrated in  FIG. 12  will represent the features and contours of the inner surface of the appliance itself, that will be positioned against or adjacent to the subject body surfaces. Here, it should be noted that milling cutter  84  is intended to be representative of a variety of cutters that can be used, but is not intended to be limiting in configuration, shape and/or size. 
       FIGS. 14 and 14   a  illustrate additional appliances  86  and  88  that can be made using the processes of  FIGS. 11 ,  12  and  13 , like parts of appliances  86  and  88  and  10  and  52 , being identified by like numerals. Appliance  86  is configured for placement on a lower jaw, and appliance  88  being configured for placement on an upper jaw, each including multiple catheters  20  for receiving wires, as illustrated by wire  22 , in the above-discussed manner, and shields  28 .  FIGS. 15 and 16  are sectional views of appliance  88 , including passages  90  and grooves  92 , respectively, that can either form the catheters  20  (passages  90 ), or receive them (passages  90  and grooves  92 ), and which can be computer positioned as part of the mapping process and/or the manufacturing process, and incorporated into the appliance when made. Appliance  88  in these views also includes appropriately positioned shields  28 . 
     Thus, there has been shown and described a novel_brachytherapy appliance and method, which overcomes many of the problems and shortcomings set forth above. It will be apparent, however, to those familiar in the art, that many changes, variations, modifications, and other uses and applications for the subject device are possible. All such changes, variations, modifications, and other uses and applications that do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.