Abstract:
Shielding assemblies for systems that generate and infuse radiopharmaceuticals. The shielding assemblies include a sidewall that defines several compartments and provides a radiation barrier for the compartments and provides a passageway sized to accommodate routing of an eluate line from a radioisotope generator. One compartment is sized to contain the radioisotope generator. A second compartment is sized to hold a portion of an infusion circuit that may be an extension of the eluate line and may include a waste line and a patient line.

Description:
RELATED APPLICATIONS 
       [0001]    The present application is related to the following commonly assigned utility patent applications, all of which are filed concurrently herewith and all of which are hereby incorporated by reference in their entireties: Practitioner Docket No. 56782.1.5, entitled: SHIELDING ASSEMBLIES FOR INFUSION SYSTEMS; Practitioner Docket No. 56782.1.7, entitled: INFUSION SYSTEMS INCLUDING COMPUTER-FACILITATED MAINTENANCE AND/OR OPERATION AND METHODS OF USE; and Practitioner Docket No. 56782.1.8, entitled: CABINET STRUCTURES SUPPORTING INFUSION SYSTEMS. 
       TECHNICAL FIELD 
       [0002]    The present invention pertains to configurations of systems that generate and infuse radiopharmaceuticals, and, more particularly, to the routing of infusion circuit tubing lines. 
       BACKGROUND 
       [0003]    Nuclear medicine employs radioactive material for therapy and diagnostic imaging. Positron emission tomography (PET) is one type of diagnostic imaging, which utilizes doses of radiopharmaceutical, for example, generated by elution within a radioisotope generator, that are injected, or infused into a patient. The infused dose of radiopharmaceutical is absorbed by cells of a target organ, of the patient, and emits radiation, which is detected by a PET scanner, in order to generate an image of the organ. An example of a radioactive isotope, which may be used for PET, is Rubidium-82 (produced by the decay of Strontium-82); and an example of a radioisotope generator, which yields a saline solution of Rubidium-82, via elution, is the CardioGen-82® available from Bracco Diagnostics Inc. (Princeton, N.J.). 
         [0004]    Whether the half-life of a particular radioactive isotope, employed by a radiopharmaceutical, is relatively short or long, a patient undergoing a nuclear imaging procedure is not typically exposed to a significant amount of radiation. However those personnel, whose job it is to set up and maintain radiopharmaceutical infusion systems, and to administer doses therefrom, are subject to more frequent and prolonged exposures to radiation. Therefore, shielding assemblies, which provide a radiation barrier to protect these personnel from excessive exposure to radiation sources, are an important component of radiopharmaceutical generators and infusion systems. These shielding assemblies are typically formed with lead sidewalls, the bulk and weight of which can pose difficulties for the personnel who regularly set up disposable tubing lines for the infusion circuit of the infusion system. These lines should be routed into and out from compartments of the shielding assembly without kinking or crushing the lines. Thus, there is a need for new infusion system configurations and assemblies that facilitate this task. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The following drawings are illustrative of particular embodiments of the present invention and therefore do not limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description. Embodiments of the present invention will hereinafter be described in conjunction with the appended drawings, wherein like numerals denote like elements. 
           [0006]      FIG. 1A  is a first perspective view of an infusion system, according to some embodiments of the present invention. 
           [0007]      FIG. 1B  is another perspective view of a portion of a cabinet structure of the system shown in  FIG. 1A , according to some embodiments. 
           [0008]      FIG. 1C  is a second perspective view of the system shown in  FIG. 1A , according to some embodiments. 
           [0009]      FIG. 1D  is a schematic of an infusion circuit, according to some embodiments of the present invention. 
           [0010]      FIG. 2A  is a perspective view of a shielding assembly for an infusion system, such as that shown in  FIGS. 1A-C , according to some embodiments of the present invention. 
           [0011]      FIG. 2B  is a perspective view of a framework of the system, according to some embodiments, with an enlarged detailed view of a component of the system, according to some embodiments. 
           [0012]      FIG. 3A  is another perspective view of the shielding assembly shown in  FIG. 2A . 
           [0013]      FIG. 3B  is a perspective view of the infusion circuit, shown in  FIG. 1C , configured and routed, according to some embodiments. 
           [0014]      FIG. 3C  is a perspective view of a disposable infusion circuit subassembly, according to some embodiments. 
           [0015]      FIG. 3D  is a frame for the subassembly shown in  FIG. 3C , according to some embodiments. 
           [0016]      FIG. 4  is a main menu screen shot from an interface of a computer, which may be included in systems of the present invention, according to some embodiments. 
           [0017]      FIG. 5A  is a schematic showing a first group of successive screen shots from the computer interface, according to some embodiments. 
           [0018]      FIG. 5B  is a pair of screen shots from the computer interface, which provide indications related to eluant volume levels in a reservoir of the system, according to some embodiments. 
           [0019]      FIG. 5C  is a schematic showing a second group of successive screen shots from the computer interface, according to some embodiments. 
           [0020]      FIG. 6  is a schematic showing a third group of successive screen shots from the computer interface, according to some embodiments. 
           [0021]      FIGS. 7A-C  are schematics showing a fourth group of successive screen shots from the computer interface, according to some embodiments. 
           [0022]      FIGS. 8A-B  are schematics showing a fifth group of successive screen shots from the computer interface, according to some embodiments. 
           [0023]      FIGS. 9A-C  are schematics showing a sixth group of successive screen shots from the computer interface, according to some embodiments. 
           [0024]      FIG. 10  is a schematic showing a seventh group of successive screen shots from the computer interface, according to some embodiments. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    The following detailed description is exemplary in nature and is not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the following description provides practical illustrations for implementing exemplary embodiments. Utilizing the teaching provided herein, those skilled in the art will recognize that many of the examples have suitable alternatives that can be utilized. 
         [0026]      FIG. 1A  is a first perspective view of an infusion system  10 , according to some embodiments of the present invention, wherein system  10  is shown supported by a cabinet structure, which includes a platform  113  (seen better in  FIG. 2B ) and a shell  13 ; shell  13  extends upward from a skirt  11 , that surrounds platform  113 , to surrounds an interior space in which a portion of infusion system  10  is contained (—seen in  FIG. 1C ). Shell may be formed from panels of injection-molded polyurethane fitted together according to methods known to those skilled in the art.  FIG. 1A  illustrates the cabinet structure of system  10  including a grip or handle  14 , which extends laterally from shell  13 , in proximity to an upper surface  131  thereof, and a post  142 , which extends upward from shell  13 , and to which a work surface, or tray  16  and a computer  17  are, preferably, attached, via an ergonomic, positionable mount. According to some embodiments, computer  17  is coupled to a controller of system  10 , which is mounted within the interior space surrounded by shell  13 , and a monitor  172  of computer  17  not only displays indications of system operation for a user of system  10 , but also serves as a device for user input (e.g. touch screen input). However, according to alternate embodiments, another type of user input device, known to those skilled in the art, may be employed by computer  17 . Other types of user input devices may included, for example, a keyboard, a series of control buttons or levers, a barcode reader (or other reader of encoded information), a scanner, a computer readable medium containing pertinent data, etc. The user input device may be mounted on the cabinet structure of system  10 , as shown, or may be tethered thereto; alternatively the user input device may be remote from system  10 , for example, located in a separate control room. According to some additional embodiments, another user input device, for example, in addition to a touch screen of computer  17 , may be remote from system  10  and used to start and stop infusions. Operation of system  10 , which is facilitated by computer  17 , will be described below, in conjunction with  FIGS. 4-9C . 
         [0027]      FIG. 1A  further illustrates two pairs of wheels  121 ,  122 , mounted to an underside of platform  113 , to make system  10  mobile; handle  14  is shown located at an elevation suitable for a person to grasp in order to maneuver system  10 , from one location for another, upon pairs of wheels  121 ,  122 . According to some preferred embodiments, one or both pairs of wheels  121 ,  122 , are casters, allowing for rotation in a horizontal plane (swivel), in order to provide additional flexibility for maneuvering system  10  in relatively tight spaces. 
         [0028]      FIG. 1B  is a perspective view of a portion of system  10 , on a side  111  of the cabinet structure, which is in proximity to wheels  121 .  FIG. 1B  illustrates a lever or pedal  125 , which is located for activation by a foot of the person, who grasps handle  14  to maneuver system  10 . In a neutral position, pedal  125  allows wheels  121 ,  122  to rotate, and, if embodied as casters, to swivel freely. Pedal  125  may be depressed to a first position which prevents a swiveling of wheels  122 , according to those embodiments in which wheels  122  are casters, and may be further depressed to brake wheels  121 ,  122  from rolling and swiveling, upon reaching a desired location.  FIG. 1B  further illustrates a rear access panel  174 , for example, providing access to circuit boards of the aforementioned controller contained within the interior space surrounded shell  13 , an optional lock  184 , to secure panel  174 , a power jack  118 , for connecting system  10  to a power source, and a printer  117  for providing documentation of each patient infusion carried out by system  10 , and of system quality control test results. In some embodiments, system  10  may further include one or more additional connectors, or ports (not shown), which allow system  10  to be coupled to, for communication with, other devices used for nuclear imaging procedures. 
         [0029]      FIG. 1A  further illustrates upper surface  131  of shell  13  including several openings  133 ,  135 ,  139  formed therein.  FIG. 1C  is a partially exploded perspective view of system  10 , wherein a removable access panel  132  is shown as a contoured portion of upper surface  131 , which, when exposed, by lifting away a bin  18 , that mates therewith, may be removed from another opening  137  formed in upper surface  131 .  FIG. 1C  also provides a better view of another panel  134  which may be lifted away from opening  139 . According to the illustrated embodiment, openings  139  and  137  provide a user of system  10  with independent access to separate portions of infusion system  10 , which are contained within shell  13 , for example, to set up and maintain system  10 ; and openings  133  and  135  provide passageways for tubing lines to pass through shell  13 .  FIG. 1C  further illustrates an optional switch  102 , which in case of an emergency, may be activated to abort function of system  10 . With reference to  FIGS. 1A and 1C , it may be appreciated that an arrangement of features formed in upper surface  131  of shell  13 , in conjunction with bin  18 , tray  16  and computer  17 , provide a relatively ergonomic and organized work area for technical personnel who operate system  10 . 
         [0030]    Turning now to  FIG. 1D , a schematic of an infusion circuit  300 , which may be incorporated by system  10 , is shown.  FIG. 1D  illustrates circuit  300  generally divided into a first part  300 A, which includes components mounted outside shell  13 , and a second part  300 B, which includes components mounted within the interior space surrounded by shell  13 . (Parts  300 A and  300 B are delineated by dotted lines in  FIG. 1D .)  FIG. 1D  further illustrates second part  300 B of circuit  300  including a portion contained within a shielding assembly  200 , which is designated schematically as a dashed line. Some embodiments of shielding assembly  200  will be described in greater detail, in conjunction with  FIGS. 2A-B  and  3 A-B, below. 
         [0031]    According to the illustrated embodiment, circuit  300  includes an eluant reservoir  15 , for example, a bag, bottle or other container, containing saline as the eluant, which is shown hanging from a post, or hanger  141  above upper surface  131  of shell  13  in  FIG. 1A ; a syringe pump  33 , for pumping the eluant from reservoir  15 , and a pressure syringe  34 , for monitoring pumping pressure; a filter  37 , which may also serve as a bubble trap, for the pumped eluant; a radioisotope generator  21 , through which the filtered eluant is pumped to create a radioactive eluate, for example an eluate carrying Rubidium-82 that is generated by the decay of Strontium-82, via elution, within a column of generator  21 ; and an activity detector  25 , for measuring the activity of the eluate discharged from generator  21 , in order to provide feedback for directing the flow of the eluate, via a divergence valve  35 WP, either to a waste bottle  23  or through a patient line  305   p,  for example, to inject a dose of the radiopharmaceutical eluate into a patient. With reference back to  FIG. 1A , patient line  305   p  is shown extending out from shell  13 , through opening  135 , to a distal end thereof, which, according to some embodiments, includes a filter. Patient line  305   p  may be coupled to another line that includes a patient injection needle (not shown). Alternatively, patient line  305   p  may be coupled to another line (not shown), which extends from a source of another active substance, for example, a stress agent; the other line is coupled to the line that includes the patient injection needle, in order to permit injection of the additional active substance.  FIG. 1D  illustrates an eluant tubing line  301  coupled to reservoir  15  and to pump  33 , and, with reference to  FIGS. 1A-B , it may be appreciated that opening  133  provides the passageway for tubing line  301  to enter the interior space surrounded by shell  13 . According to some preferred embodiments, opening  133  includes a grommet-type seal that prevents leakage of eluant, which may spill from reservoir  15 , into the interior space through opening  133 , while allowing a user to assemble tubing line  301  through opening  133 . Likewise opening  135 , which provides a passageway for patient line  305   p,  may include a grommet-type seal. 
         [0032]      FIG. 1D  further illustrates another eluant tubing line  302  coupled to pump  33  and a divergence valve  35 BG, which may either direct pumped eluant through a tubing line  304 , to generator  21 , or direct the pumped eluant through a by-pass tubing line  303 , directly to patient line  305   p.  Divergence valve  35 BG, as well as divergence valve  35 WP, which directs eluate from an eluate tubing line  305  either to a waste line  305   w  or to patient line  305   p,  may each be automatically operated by a corresponding servomotor (not shown), coupled to the controller (not shown) of system  10 , which controller receives feedback from activity detector  25 . When system  10  is operating for automatic infusion, to deliver a dose of radiopharmaceutical to a patient, for example, Rubidium-82 for diagnostic imaging, divergence valve  35 BG is initially set to direct eluant to generator  21  and divergence valve  35 WP is set to direct eluate from generator into waste bottle  23 , until activity detector  25  detects the desired activity of the eluate, at which time the feedback from activity detector  25  causes the controller to direct the corresponding servo-motor to re-set valve  35 WP for diverting the flow of eluate into patient line  305   p.  According to some embodiments, once a prescribed volume of the eluate has passed through patient line  305   p,  the controller directs the corresponding servomotor to re-set divergence valve  35 BG for diverting the flow of eluant through by-pass line  303  and into patient line  305   p  in order to flush, or push any eluate remaining in patient line  305   p  into the patient. According to some embodiments, the controller may also direct the corresponding servomotor to re-set divergence valve  35 WP back toward waste bottle  23 , prior to the flush through by-pass line  303 , in order to prevent back flow of eluant, through line  305 , toward generator  21 . 
         [0033]    With further reference to  FIG. 1D , it may be appreciated that shielding assembly  200  encloses those portions of circuit  300  from which radioactive radiation may emanate, with the exception of that portion of patient line  305   p,  which must extend out from shielding assembly  200  in order to be coupled to the patient for injection, or in order to be coupled to shielded sample vials, as will be described below. Thus, technical personnel, who operate system  10 , are protected from radiation by shielding assembly  200 , except at those times when an infusion is taking place, or when quality control tests require collection of eluate into sample vials. During infusions and quality control test sample collection, all technical personnel are typically in another room, or otherwise distanced from system  10 , in order to avoid exposure to radiation during the infusion, and, according to some preferred embodiments of the present invention, system  10  includes at least one means for informing technical personnel that an infusion is about to take place or is taking place. With reference back to  FIGS. 1A and 1C , system  10  is shown including a light projector  100 , mounted on post  142 . According to the illustrated embodiment, projector  100 , projects a light signal upward, for maximum visibility, when pump  33  is pumping eluant and elution is taking place within generator  21 , or at all times when pump  33  is pumping eluant. According to some embodiments, the light signal flashes on and off when the eluate is being diverted from generator  21  into waste bottle  23 , and the light signal shines steadily when the eluate is being diverted through patient line  305   p,  or visa versa. According to other embodiments, a projector  100  shines a light having a first color, to indicate that eluate is being diverted to waste bottle  23 , and then shines a light having a second, different color, to indicate that eluate is being directed to patient line  305   p  for infusion. Light projector  100  may further project a more rapidly flashing light, for example, for approximately five seconds, once a peak bolus of radioactivity is detected in the eluate, to provide further information to technical personnel. Alternative means of informing technical personnel that an infusion is taking place may also be incorporated by system  10 , for example, including audible alarms or other types of visible or readable signals that are apparent at a distance from system, including in the control room. 
         [0034]    When maintenance of system  10  requires the emptying waste bottle  23 , relatively easy access to waste bottle  23  is provided through opening  139  in top surface  131  of shell  13 . It should be noted that technical personnel are preferably trained to empty waste bottle  23  at times when the eluate, contained in waste bottle  23 , has decayed sufficiently to ensure that the radioactivity thereof has fallen below a threshold to be safe. Opening  139  is preferably located at an elevation of between approximately 2 feet and approximately 3 feet; for example, opening  139  may be at an elevation of approximately 24 inches, with respect to a lower surface of platform  113 , or at an elevation of approximately 32 inches, with respect to a ground surface upon which wheels  121 ,  122  rest. According to the illustrated embodiment, opening  139  is accessed by lifting panel  134 ; just within opening  139 , a shielded lid or door  223  ( FIG. 2A ) may be lifted away from a compartment of shielding assembly  200  that contains waste bottle  23 . With further reference to  FIG. 1C , it may be appreciated that opening  137  provides access to other portions of circuit  300  for additional maintenance procedures, such as changing out generator  21  and/or other components of circuit  300 , as will be described below. 
         [0035]      FIGS. 1A and 1C  further illustrate a pair of relatively shallow external recesses  190 , which are formed in upper surface  131  of shell  13 , for example, in order to catch any spills from infusion system; one of recesses  190  is shown located in proximity to post, or hanger  141 , which holds reservoir  15 , and in proximity to opening  133 , through which tubing line  301  passes. Another recess  192  is shown formed in upper surface  131 ; a width and depth of recess  192  may accommodate storage of technical documentation associated with infusion system  10 , for example, a technical manual and/or maintenance records, or printouts from printer  117  ( FIG. 1B ). With reference to  FIG. 1C , upper surface  131  of shell  13  is shown to also include additional recesses  101 , which are each sized to hold a shielded test vial, which contains samples from infusion system  10 , for example, for breakthrough testing and/or calibration, which will be described in greater detail, below. Additional receptacles  180  are shown formed in bin  18 , on either side of a handle  182 , which facilitates removal of bin  18  away from shell  13 . Technical personnel may, thus, conveniently transport bin  18  to a storage area for a collection of supplies, for example, sharps, gloves, tubing lines, etc . . . , into one or more receptacles  180  thereof, and/or to a waste container where separate receptacles  180  of bin  18  may be emptied of waste, such as packaging for the aforementioned supplies, for example, deposited therein during infusion procedures. 
         [0036]      FIG. 2A  is a perspective view of shielding assembly  200 , according to some embodiments of the present invention. With reference to  FIGS. 1C and 2A , together, it may be appreciated that opening  137 , in upper surface  131  of shell  13 , provides access to a lid or door  221  of a sidewall  201  of shielding assembly  200 , which sidewall  201  encloses a compartment sized to contain a radioisotope generator of system  10 , for example, generator  21 , previously introduced. According to the illustrated embodiment, opening  137  and door  221  are located at a lower elevation, for example, with respect to platform  113 , than are opening  139  and lid  223 , which provide access to the compartment being formed by a sidewall  203  of shielding assembly  200  to contain waste bottle  23 , as previously described. When panel  132  is separated from shell  13 , and door  221  opened, generator  21  may be lifted out from an opening  231  ( FIG. 3A ) which mates with door  221  of sidewall  201 . A weight of generator  21 , which includes its own shielding, may be between approximately 23 and approximately 25 pounds, thus, according to some preferred embodiments of the present invention, the elevation of each of openings  137  and  231 , with respect to the lowermost portion of the cabinet structure, is between approximately 1 foot and approximately 2 feet, in order to facilitate an ergonomic stance for technical personnel to lift generator  21  out from the compartment. According to an exemplary embodiment, when shielding assembly  200  is contained in the cabinet structure of  FIG. 1A , openings  137  and  231  are located at an elevation of approximately 12 inches, with respect to the lower surface of platform  113 , or at an elevation of approximately 19 inches, with respect to the ground surface upon which wheels  121 ,  122  rest.  FIG. 1C  further illustrates access panel  132  including a security lock  138 , which mates with a framework  19  of system  10 , shown in  FIG. 2B , in order to limit access to generator  21 . 
         [0037]      FIGS. 1C and 2A  further illustrate a lid or a door  225  of another sidewall  205  ( FIG. 3A ) of shielding assembly  200 , which encloses another compartment that is accessible through opening  137  of shell  13 , and which is located adjacent the compartment enclosed by sidewall  201 . Each of doors  221 ,  225  are shown being attached by a corresponding hinge H, and another door  227  is shown attached to sidewall  203  by another hinge H.  FIG. 2A  illustrates each of lid  223  and doors  221 ,  225 ,  227  including a handle  232 ,  212 ,  252  and  272 , respectively, for moving lid  223  and doors  221 ,  225 ,  227 , in order to provide access to the corresponding compartments, which can be seen in  FIGS. 3A-B .  FIG. 2A  further illustrates optional thumb screws  290 , one securing lid  223  to sidewall  203  and another securing door  221  to sidewall  201 , or other means for securing the doors, which are known to those skilled in the art, may be incorporated. Each sidewall  201 ,  203 ,  205  and the corresponding lid/door  223 ,  221 ,  225 ,  227  thereof may be individually cast from 3% antimony lead, or from other known shielding materials, and then assembled together according to methods known to those skilled in the art. 
         [0038]    According to the illustrated embodiment, doors  221 ,  225  are hinged to open in an upward direction, per arrows D and C, and, with reference back to  FIG. 1C , a latch component  191  is provided to hold each of doors  221 ,  225  in an opened position, thereby, preventing doors  221 ,  225  from falling closed, which could pinch/crush fingers of technical personnel and/or tubing lines of circuit  300 , when in the midst of a maintenance procedure.  FIG. 2B  is a perspective view of framework  19  of the cabinet structure of system  10 , according to some embodiments, to which latch component  191  is mounted;  FIG. 2B  includes an enlarged detailed view of latch component  191 , according to some embodiments.  FIG. 2B  illustrates latch component  191  including a first pin  193 , corresponding to door  225 , and a second pin  195 , corresponding to door  221 ; each pin  193 ,  195  includes a lever end  193 A,  193 B, respectively, and a holding end  193 B,  195 B, respectively. An edge of each door  221 ,  225 , upon opening of doors  221 ,  225 , may push past the holding end  195 B,  193 B of the corresponding pin  195 ,  193 , in a first direction, per arrow F, and then may rest against a respective side S 95  and S 93  of each end  195 B,  193 B, until the corresponding lever end  195 A,  193 A is rotated in a counter-clockwise direction, per arrow cc, thereby moving the corresponding holding end  193 B,  195 B to make way for the closing of doors  221 ,  225 . Doors  221 ,  225  being held by latch component  191  in an open position may be seen in  FIG. 3A . 
         [0039]    With further reference to  FIG. 2A , according to some preferred embodiments of the present invention, an edge of door  225  overlaps door  221  to prevent door  221  from being opened, per arrow D, if door  225  is not opened, per arrow C; and an edge of door  227  overlaps an edge of door  225  to prevent door  225  from being opened if door  227  is not opened, per arrow B; and an edge of lid  223  overlaps door  227  to prevent door  227  from being opened if lid  223  is not opened, per arrow A. Thus, access to the compartment enclosed by sidewall  201  and containing generator  21  is only systematically allowed through a sequential opening of lid  223  and doors  227 ,  225 ,  221 , since, when generator  21  is replaced it is typically desirable to also replace those portions of circuit  300  which are shielded behind lid  223  and doors  227 ,  225 . The routing of these portions of circuit  300  will be described in conjunction with  FIGS. 3A-C . 
         [0040]      FIG. 3A  is another perspective view of shielding assembly  200 , according to some embodiments of the present invention. In  FIG. 3A , lid  223  and doors  221 ,  225 , and  227  are opened to provide a view into openings  233 ,  235  and  231  of sidewalls  203 ,  205  and  201 , respectively, and into a passageway  207 , which is formed in sidewall  203 , opposite the compartment, which contains waste bottle  23 . Passageway  207  is shown extending vertically along sidewall  203  and having a grooved extension  213  formed in a perimeter surface of opening  233 . An optional retaining member  237 , for example, formed from an elongate strip of resilient plastic having a generally c-shape cross-section, is shown being mounted along a length of passageway  207  to hold lines  305   w  and  305   p  in place within passageway  207 .  FIG. 3A  further illustrates a pair of passageways  251   b  and  251   g,  which are formed as grooves in a portion of sidewall  205 , and another pair of passageways  215   i  and  215   o,  which are formed as grooves in a portion of sidewall  201 . A routing of portions of tubing circuit  300  ( FIG. 1D ) through passageways  207 ,  251   b,    251   c,    215   i  and  215   o  is shown in  FIG. 3B . 
         [0041]      FIG. 3B  illustrates tubing line  304  being routed through passageways  251   g  and  215   i,  eluate tubing line  305  being routed through passageway  215   o,  and both waste line  305   w  and patient line  305   p  being routed along passageway  207 . Waste line  305   w  further extends through grooved extension  213  to waste bottle  23 , and patient line  305   p  further extends outward from shielding assembly  200 , for example, to extend out through opening  135  in upper surface  131  of shell  13  ( FIG. 1A ). According to the illustrated embodiment, each passageway formed in shielding assembly  200 , by being accessible along a length thereof, can facilitate a relatively easy routing of the corresponding tubing line therethrough, when the corresponding lid/door is open, and a depth of each passageway prevents pinching and/or crushing of the corresponding tubing line routed therethrough, when the corresponding lid/door is closed down thereover. 
         [0042]      FIG. 3A  further illustrates sidewall  205  including a valve actuator receptacle  253 , into which divergence valve  35 WP is mounted, to be controlled by one of the servomotors (not shown) of system  10 , and an opening  325  for activity detector  25 . Activity detector  25  is mounted in a shielded well  255  that extends downward from opening  325  (shown in  FIG. 3B ), and, with reference to  FIG. 3B , tubing line  305  passes over opening  325  so that detector  25  can detect an activity of the eluate, which passes therethrough. According to some embodiments, the positioning, within the compartment enclosed by sidewall  205 , of the components of the portion of infusion circuit  300  which are shown routed therein, is facilitated by providing the components mounted in a frame  39  as a disposable subassembly  390 , an embodiment of which is illustrated by  FIGS. 3C-D . 
         [0043]      FIG. 3C  is a perspective view of subassembly  390 , and  FIG. 3D  is a perspective view of frame  39 . According to the embodiment illustrated by  FIG. 3D , frame  39  is formed from mating trays  39 A,  39 B, for example, formed from a thermoformed plastic, which fit together to capture, therebetween, and hold, in fixed relation to a perimeter edge of frame  39 , divergence valve  35 WP and portions of eluant tubing line  304 , by-pass tubing line  303 , eluate tubing line  305 , waste line  305   w  and patient line  305   p.    FIG. 3C  illustrates the perimeter edge divided into a first side  391 , a second side  392 , opposite first side  391 , a third side  393 , extending between first and second sides  391 ,  392 , and a fourth side  394 , opposite third side  393 . Although  FIG. 3D  shows trays  39 A,  39 B individually formed for fitting together, according to alternate embodiments, mating trays of frame  39  may be parts of a continuous sheet of plastic folded over on itself. 
         [0044]    According to the illustrated embodiment, an end  404 A, of eluant line  304 , and an end  403 , of by-pass line  303  extend from third side  393  of frame  39  to couple with divergence valve  35 BG and an upstream section of eluant tubing line  302 .  FIG. 3C  further illustrates an opposite end  404 B of eluant line extending from first side  391  of frame  39 , alongside a similarly extending end  405  of eluate line  305 , and ends  406  and  407  of patient line  305   p  and waste line  305   w,  respectively, extending from second side  392  of frame  39 . Although ends  406 ,  407  are shown extending upward from tray  39   a,  as they would within shielding assembly  200 , it should be appreciated that the tubing lines of circuit  300  are preferably flexible and would drop down under their own weight rather than extending upward, as shown, if not supported. Referring back to  FIG. 1D , in conjunction with  FIG. 3C , it can be seen that fittings are provided for coupling subassembly  390  into circuit  300 : a first fitting  311  couples the section of eluant line  302  to filter  37 ; a second fitting  312  couples eluant line  304  to an inlet port of generator  21 ; a third fitting  313 , which may incorporate a check valve, couples eluate line  305  to an outlet port of generator  21 ; a fourth fitting  314  couples waste line  305   w  to waste bottle  23 ; and a fifth fitting  315  couples patient line  305   p  to an extension thereof, which extends outside shell  13  (designated by the dotted line). Each of the fittings  311 ,  312 ,  313 ,  314 ,  315  may be of the Luer type, or any other suitable type that is known to those skilled in the art. 
         [0045]    As previously mentioned, when generator  21  is replaced, it is typically desirable to also replace those portions of circuit  300  which are shielded behind lid  223  and doors  227 ,  225 , and, in those instances wherein system  10  is moved to a new site each day, these portions may be replaced daily. Thus, according to the illustrated embodiment, these portions are conveniently held together by frame  39 , as subassembly  390 , in order to facilitate relatively speedy removal and replacement, while assuring a proper assembly orientation, via registration with features formed in sidewall  205  ( FIG. 3A ), for example: registration of divergence valve  35 WP with valve actuator receptacle  253 , registration of tubing line ends  403  and  404 A with passageways  251   b  and  251   g,  respectively, registration of tubing line ends  404 B and  405  with passageways  215   i  and  215   o,  respectively, and registration of tubing line ends  406  and  407  with passageway  207 . 
         [0046]    With further reference to  FIG. 3B , other portions of tubing circuit  300  are shown.  FIG. 3B  illustrates eluant tubing line  301  extending from reservoir  15 , outside of shell  13  ( FIG. 1A ), to syringe pump  33 , which is mounted to an actuating platform  433 . According to the illustrated embodiment, platform  433  is actuated by another servomotor (not shown) of system  10 , which is controlled by the controller and computer  17  of system  10 , to cause a plunger of pump  33  to move, per arrow I, so as to draw in eluant, from reservoir  15 , through tubing line  301 , and then to cause the plunger to move in the opposite direction so as to pump the eluant, through tubing line  302 , to either generator  21  or to by-pass line  303 . Although the illustrated embodiment includes syringe pump  33 , other suitable pumps, known to those skilled in the art, may be substituted for pump  33 , in order to draw eluant from reservoir  15  and to pump the eluant throughout circuit  300 . Although not shown, it should be appreciated that divergence valve  35 BG is fitted into another valve actuating receptacle mounted within shell  13  and coupled to yet another servomotor (not shown) of system  10 . 
         [0047]      FIG. 3B  further illustrates a filter holder  317  that is mounted alongside an interior surface of shell  13  to hold filter  37  ( FIG. 1D ) of tubing line  302 . Filter holder  317 , like frame  39  for subassembly  390 , may be formed from a thermoformed plastic sheet; holder  317  may have a clam-shell structure to enclose filter  37  in an interior space, yet allow tubing line  302 , on either side of filter  37 , to extend out from the interior space, in between opposing sides of the clam-shell structure. Holder  317  is shown including an appendage  307  for hanging holder  317  from a structure (not shown) inside shell  13 . 
         [0048]    Turning now to  FIGS. 4-9C  details concerning computer-facilitated operation of system  10  will be described, according to some embodiments of the present invention. As previously mentioned, and with reference back to  FIG. 1A , computer  17  of system  10  includes monitor  172 , which, preferably, not only displays indications of system operation to inform a user of system  10 , but is also configured as a touch screen to receive input from the user. It should be understood that computer  17  is coupled to the controller of system  10 , which may be mounted within the interior space surrounded by shell  13 . Although  FIG. 1A  shows computer  17  mounted to post  142  of system  10 , for direct hardwiring to the controller of system  10 , according to some alternate embodiments, computer  17  is coupled to the controller via a flexible lead that allows computer  17  to be positioned somewhat remotely from those portions of system  10 , from which radioactive radiation may emanate; or, according to some other embodiments, computer  17  is wirelessly coupled, for example, via two-way telemetry, to the controller of system  10 , for even greater flexibility in positioning computer  17  away from radioactive radiation. 
         [0049]    According to some preferred embodiments, computer  17  is pre-programmed to guide the user, via monitor  172 , through procedures necessary to maintain system  10 , to perform quality control tests on system  10 , and to operate system  10  for patient infusions, as well as to interact with the user, via the touch-screen capability of monitor  172 , according to preferred embodiments, in order to track volumes of eluant and eluate contained within system  10 , to track a time from completion of each elution performed by system  10 , to calculate one or more system parameters for the quality control tests, and to perform various data operations. It should be understood that screen shots shown in  FIGS. 4-9C  are exemplary in nature and are presented to provide an outline of some methods of the present invention in which computer  17  facilitates the aforementioned procedures, without limiting the scope of the invention to any particular computer interface format. 
         [0050]      FIG. 4  is a screen shot of a main menu  470 , which is presented by computer  17  on monitor  172 , according to some embodiments. Main menu  470  includes a listing of each computer-facilitated operation that may be selected by the user, once the user has logged on. 
         [0051]      FIG. 5A  is a schematic showing a series of screen shots which includes a log in screen  570 . After the user enters the appropriate information into data entry fields of log in screen  570 , computer  17  presents a request for the user to confirm the volume of eluant that is within reservoir  15  (e.g. saline in saline bag), via a screen  571 , and then brings up main menu  470 . According to some embodiments, when the user touch-selects the data entry fields of screen  570  or  571 , or of any of the other screens presented herein, below, a virtual keyboard is displayed for touch-select data entry into the selected data entry field; alternately, computer  17  may be augmented with another type of device for user data entry, examples of which include, without limitation, a peripheral keyboard device, a storage medium (i.e. disk) reader, a scanner, a barcode reader (or other reader of encoded information), a hand control (i.e. mouse, joy stick, etc . . . ). 
         [0052]    If the user determines that the volume of eluant/saline is insufficient, the user selects a menu item  573 , to replace the saline bag, which leads computer  17  to prompt the user to enter a quantity of saline contained by the new saline bag, via a screen  574 . Thus, computer  17  uses either the confirmed eluant/saline volume, via screen  571 , or the newly entered eluant/saline volume, via screen  574 , as a baseline from which to track depletion of reservoir volume, via activations of pump  33 , in the operation of system  10 . With reference to  FIG. 5B , during the operation of system  10 , when computer  17  detects that the eluant reservoir/saline bag has been depleted to a predetermined volume threshold, computer  17  warns the user, via a screen  577 . If the user has disregarded screen  577  and continues to deplete the saline bag, computer  17  detects when the saline bag is empty and provides indication of the same to the user, via a screen  578 . To replenish the reservoir/saline bag, the user may either refill the reservoir/bag or replace the empty reservoir/bag with a full reservoir/bag. According to some embodiments, system  10  automatically precludes any further operation of the system until the reservoir is replenished. 
         [0053]    In addition to tracking the volume of eluant in reservoir  15 , computer  17  also tracks a volume of the eluate which is discharged from generator  21  into waste bottle  23 . With reference to  FIG. 5C , an item  583  is provided in main menu  470 , to be selected by the user when the user empties waste bottle  23 . When the user selects item  583 , computer  17  presents a screen  584 , by which the user may effectively command computer  17  to set a waste bottle level indicator to zero, once the user has emptied waste bottle  23 . Typically, the user, when powering up system  10  for operation, each day, will either empty waste bottle  23 , or confirm that waste bottle  23  was emptied at the end of operation the previous day, and utilize screen  584  to set the waste bottle level indicator to zero. Thus, computer  17 , can track the filling of waste bottle  23  via monitoring of the operation of pump  33  and divergence valve  35 WP, and provide an indication to the user when waste bottle  23  needs to be emptied, for example, via presentation of screen  584 , in order to warn the user that, unless emptied, the waste bottle will overflow. According to some embodiments, system  10  automatically precludes any further operation of the system until the waste bottle is emptied. 
         [0054]    In addition to the above maintenance steps related to eluant and eluate volumes of system  10 , the user of system  10  will typically perform quality control tests each day, prior to any patient infusions. With reference to  FIG. 6 , according to preferred methods, prior to performing the quality control tests (outlined in conjunction with  FIGS. 7A-C  and  8 A-B), the user may select an item  675  from main menu  470 , in order to direct system  10  to wash the column of generator  21 . During the generator column wash, which is performed by pumping a predetermined volume of eluant, for example, approximately 50 milliliters, through generator  21  and into waste bottle  23 , computer  17  provides an indication, via a screen  676 , that the wash is in progress. Also, during the generator column wash, the system may provide a signal to indicate that eluate it being diverted to waste bottle  23 , for example, light projector  100  ( FIG. 1C ) may project a flashing light signal, as previously described. 
         [0055]      FIG. 6  further illustrates a screen  677 , which is presented by computer  17  upon completion of the column wash, and which provides an indication of a time lapse since the completion of the wash, in terms of a time countdown, until a subsequent elution process may be effectively carried out. While screen  677  is displayed, system  10  may be refilling, from reservoir  15 , pump  33 , which has a capacity of approximately 55 milliliters, according to some embodiments. According to some preferred embodiments of the present invention, computer  17  starts a timer once any elution process is completed and informs the user of the time lapse, either in terms of the time countdown (screen  677 ), or in terms of a time from completion of the elution, for example, as will be described in conjunction with  FIG. 7B . According to an exemplary embodiment, wherein generator  21  is the CardioGen-82® that yields a saline solution of Rubidium-82, produced by the decay of Strontium-82, via the elution, a time required between two effective elution processes is approximately 10 minutes. 
         [0056]    Once the appropriate amount of time has lapsed, after the elution process of generator column wash, a first quality control test may be performed. With reference to  FIG. 7A , the user may select, from main menu  470 , an item  773 A, which directs computer  17  to begin a sequence for breakthrough testing. In conjunction with the selection of item  773 A, the user attaches a needle to an end of patient line  305   p  and inserts the needle into to a test vial, for the collection of an eluate sample therefrom, and, according to  FIG. 7A , computer  17  presents a screen  774 , which instructs the user to insert the test vial into a vial shield, which may be held in recess  101  of shell  13  ( FIG. 1C ). 
         [0057]      FIG. 7A  further illustrates a subsequent screen  775 , by which computer  17  receives input, from the user, for system  10  to start the breakthrough elution, followed by a screen  776 , which provides both an indication that the elution is in progress and an option for the user to abort the elution. As previously described, the system may provide a signal to indicate that elution is in progress, for example, light projector  100  ( FIG. 1C ) may project a flashing light signal during that portion of the elution process when eluate is diverted from generator  21  through waste line  305   w  and into waste bottle  23 , and then a steady light signal during that portion of the elution process when the eluate is diverted from generator  21  through patient line  305   p  and into the test vial, for example, once activity detector  25  detects a dose rate of approximately 1.0 mCi/sec in the eluate discharged from generator  21 . Another type of light signal, for example, the more rapidly flashing light, as previously described, may be projected when a peak bolus of radioactivity is detected in the eluate. 
         [0058]    Upon completion of the elution process for breakthrough testing, computer  17  presents a screen  777 , shown in  FIG. 7B , which, like screen  677 , provides an indication of a time lapse since the completion of the elution, but now in terms of a time since completion of the breakthrough elution process. When the user transfers the vial containing the sample of eluate into a dose calibrator, to measure the activity of the sample, the user may make a note of the time lapse indicated on screen  777 . With further reference to  FIG. 7B , once the user has received the activity measure from the dose calibrator, the user proceeds to a screen  778 , which includes data entry fields for the activity measure and the time between that at which the dose calibrator measured the activity of the sample and that at which the elution was completed. The user may enter the data via the touch-screen interface of monitor  172 , or via any of the other aforementioned devices for user data entry. According to some alternate embodiments, computer  17  may receive the data, electronically, from the dose calibrator, either via wireless communication or a cable connection. 
         [0059]    After the data is entered by the user, computer  17  presents screen  779 , from which the user moves back to main menu  470  to perform a system calibration, for example, as will be described in conjunction with  FIGS. 8A-B , although the breakthrough testing is not completed. With reference back to  FIG. 7A , an item  773 B is shown, somewhat faded, in main menu  470 ; item  773 B may only be effectively selected following the completion of steps for item  773 A, so as to perform a second stage of breakthrough testing. In the second stage, the breakthrough of the sample of eluate collected in the test vial for the breakthrough testing is measured, at a time of approximately 60 minutes from the completion of the elution that produced the sample. With reference to  FIG. 7C , after the user has selected item  773 B from main menu  470 , in order to direct computer  17  to provide breakthrough test results, a screen  781  is displayed. Screen  781  includes, for reference, the values previously entered by the user in screen  778 , along with another pair of data entry fields into which the user is instructed to enter the breakthrough reading of the sample at 60 minutes and the background radiation reading, respectively. After the user enters this remaining information, as described above, computer  17  may calculate and then display, on a screen  782 , the breakthrough test results. According to the illustrated embodiment, computer  17  also displays on screen  782  pre-programmed allowable limits for the results, so that the user may verify that the breakthrough test results are in compliance with acceptable limits, before moving on to a patient infusion. According to some embodiments, system  10  will not allow an infusion if the results exceed the acceptable limits, and may present a screen explaining that the results are outside the acceptable limits; the screen may further direct the user to contact the generator supplier, for example, to order a replacement generator. 
         [0060]    With reference to  FIG. 8A , during the aforementioned 60 minute time period, while waiting to complete the breakthrough testing, the user may perform calibration by selecting item  873  from main menu  470 . Upon selection of item  873 , computer  17  presents a screen  874 , which instructs the user to insert a new test vial into an elution vial shield. In addition to placing the vial in the shield, the user, preferably, replaces patient line  305   p  with a new patient line, and then attaches a needle to the end of the new patient line for insertion into the test vial, in order to collect an eluate sample therefrom. After performing these steps, the user may move to screen  875 , wherein a plurality of data entry fields are presented; all or some of the fields may be filled in with pre-programmed default parameters, which the user has an option to change, if necessary. Once the user confirms entry of desired parameters for the calibration, the user may enter a command, via interaction with a subsequent screen  876 , to start the calibration elution. 
         [0061]    With reference to  FIG. 8B , after computer  17  starts the elution process, a screen  87  informs the user that the calibration elution is in progress and provides an option to abort the elution. As previously described, the system may provide an indication that elution is in progress, for example, light projector  100  ( FIG. 1C ) may project a flashing light signal during that portion of the elution process when eluate is diverted from generator  21  through waste line  305   w  and into waste bottle  23 , and then a steady light signal during that portion of the elution process when activity detector  25  has detected that a prescribed dose rate threshold is reached, for example, 1.0 mCi/sec, and the eluate is being diverted from generator  21 , through the new patient line, and into the test vial. Another type of light signal, for example, the more rapidly flashing light, as previously described, may be projected when a peak bolus of radioactivity is detected in the eluate. Upon completion of the elution process for calibration, computer  17  presents a screen  878 , which provides an indication of a time lapse since the completion of the elution, in terms of a time since completion of the calibration elution process. When the user transfers the vial containing the sample of eluate into the dose calibrator, to measure the activity of the sample, the user may make a note of the time lapse indicated on screen  878 . With further reference to  FIG. 8B , once the user has received the activity measure from the dose calibrator, the user proceeds to a screen  879 , which includes data entry fields for the activity measure and the time, with respect to the completion of elution, at which the dose calibrator measured the activity of the sample. Once the data is input by the user, as described above, computer calculates a calibration coefficient, or ratio, and presents the ratio on a screen  880 . According to  FIG. 8B , screen  880  further provides an indication of a desirable range for the calibration ratio and presents an option for the user to reject the calculated ratio, in which case, the user may instruct computer  17  to recalculate the ratio. 
         [0062]    With reference to  FIG. 9A , upon completion of the above-described quality control tests, the user may select an item  971 , from main menu  470 , in order to direct system  10  to begin a procedure for the generation and automatic infusion of a radiopharmaceutical into a patient. As previously described, system  10  infuses the patient with the radiopharmaceutical so that nuclear diagnostic imaging equipment, for example, a PET scanner, can create images of an organ of the patient, which absorbs the radiopharmaceutical, via detection of radioactive radiation therefrom. According to  FIG. 9A , upon selection of item  971 , computer  17  presents a screen  972  which includes a data entry field for a patient identification number. This identification number that is entered by the user is retained by computer  17 , in conjunction with the pertinent system parameters associated with the patient&#39;s infusion. After the user enters the patient identification number, computer  17  directs, per a screen  973 , the user to attach a new patient line and to purge the patient line of air. A subsequent screen  974  presented by computer  17  includes data entry fields by which the user may establish parameters for the automatic infusion; all or some of the fields may be filled in with pre-programmed default parameters, which the user has an option to change, if necessary. 
         [0063]    With reference to  FIG. 9B , if pump  33  does not contain enough eluant/saline for the patient infusion, computer  17  will present a warning, via a screen  901 , which includes an option for the user to direct the refilling of pump  33 , via a subsequent screen  902 . Once pump  33  has been filled, computer  17  presents an indication to the user, via a screen  903 . According to some embodiments, if the user does not re-fill pump  33 , yet attempts to proceed with an infusion, system  10  will preclude the infusion and present another screen, that communicates to the user that no infusion is possible, if the pump is not refilled, and asking the user to refill the pump, as in screen  901 . When pump  33  contains a sufficient volume of eluant for the patient infusion, computer  17  presents a screen  975 , which is shown in  FIG. 9C , and allows the user to enter a command for system  10  to start the patient infusion. During the infusion, computer  17  provides the user with an indication that the infusion is in process and with a option for the user to abort the infusion, via a screen  976 . As previously described, the system may provide an indication that an elution is in progress, for example, light projector  100  ( FIG. 1C ) may project a flashing light signal during that portion of the elution process when eluate is diverted from generator  21  through waste line  305   w  and into waste bottle  23 , and then a steady light signal during that portion of the elution process when activity detector  25  has detected that a prescribed dose rate threshold is reached, for example, 1.0 mCi/sec, and the eluate is being diverted from generator  21 , through the new patient line for infusion into the patient. Another type of light signal, for example, the more rapidly flashing light, previously described, may be projected when a peak bolus of radioactivity is detected in the eluate. At the completion of the infusion, a screen  977  is displayed by computer  17  to inform the user of the completion of the infusion and a time since the completion. Computer  17  also displays a summary of the infusion, per screen  978 . 
         [0064]    Printer  117  ( FIG. 1B ) may be activated to print out a hard copy of the infusion summary, on which the patient identification number and pertinent system parameters are also printed, for reference. Alternatively, or in addition, according to some embodiments, the summary of the infusion, which includes the patient identification number and pertinent system parameters, may be downloaded onto a computer readable storage device to be transferred to one or more remote computers and/or automatically transferred thereto, via wireless communication or a cable connection. The one or more remote computers may be included, for example, in a hospital information system, and/or an inventory system, and/or a billing system, and/or in a medical imaging system. With reference back to  FIG. 9A  the user may select an item  995 , from main menu  470 , in order have system  10  perform data operations, such as, archiving a data base of patient infusion information and quality control test results, transmitting patient infusion summary records to USB mass storage devices, and various types of data filtering, for example, according to date ranges and/or patient identification numbers, for example, to search for a particular set of data and/or to compile a summary report of related sets of data. 
         [0065]    Turning now to  FIG. 10 , an item  981  for computer-facilitated purging of the tubing lines of system  10  is shown included in main menu  470 . When a user selects item  981 , computer  17  guides the user to select either an air purge or a saline purge. The direction provided by computer  17  is not explicitly laid out herein, for a saline purge, as procedures for saline purging should be readily apparent to those skilled in the art, with reference to the schematic of infusion circuit  300  shown in  FIG. 1D . A saline purge of circuit  300  is desired to assure that all the air is removed from circuit  300  when a new generator and/or a new complete or partial tubing set is installed. An air purge of the tubing lines of circuit  300  may be performed after removing reservoir  15 , by-passing generator  21 , by connecting tubing line  304  to tubing line  305 , and coupling patient line  305   p  to a vial, for example, as is directed by the computer interface, in screens  983  and  984  shown in  FIG. 10 . The air purge is desirable for blowing out the tubing lines, thereby removing all remaining eluant and eluate, prior to installing a new generator and/or prior to transporting system  10  from one site to another. If generator  21  is not depleted and will be used in system  10  at the new site, it is important to by-pass the generator prior to purging the tubing lines of circuit  300  with air, so that air is not blown across the generator, since air through generator  21  may compromise both the function and the aseptic nature of generator  21 . 
         [0066]    According to preferred embodiments, once the user has followed the instructions presented in screens  983  and  984  and selects to start the air purge, for example, via screen  985 , computer  17  directs the controller of system  10  to carry out a complete air purge, in which pump  33  and divergence valves  35 BG and  35 WP are automatically controlled. The automated air purge preferably includes the following steps, which may be best understood with reference to tubing circuit  300  in  FIG. 1D : pumping any remaining volume of eluant left in pump  33 , through lines  302 ,  304 ,  305  and  305   w,  to waste bottle  23 ; refilling pump  33  with air and pumping the air through lines  302 ,  304 ,  305  and  305   w,  into waste bottle  23  (lines  304  and  305  have been previously connected directly to one another, in order to by-pass generator  21 ; if generator  21  is depleted and will be replaced with a new generator, pumping air through generator  21  may be acceptable); refilling pump  33  with air and then pumping a portion of the air through lines  302 ,  304 ,  305  and  305   p,  into the vial, and then a remaining portion of the air through lines  302 ,  304 ,  303  and  305   p,  into the vial. With reference to  FIG. 1D  and the previous description of divergence valves  35 BG,  35 WP, it should be understood how divergence valves  35 BG,  35 WP are automatically controlled to carry out the above steps. 
         [0067]    The purge operations, which are facilitated by selecting item  981  from main menu  470 , may also be accessed via the selection of an item  991  for generator setup. When the user selects item  991 , computer  17  may present an option for guidance in removing an old, depleted, generator and a set of tubing lines, prior to installing the new generator, or an option to just be guided in the installation of the new generator. 
         [0068]    In the foregoing detailed description, the invention has been described with reference to specific embodiments. However, it may be appreciated that various modifications and changes can be made without departing from the scope of the invention as set forth in the appended claims.