Abstract:
A medicinal-solution administration device includes a body unit including a drive generator that generates a drive force; and a cartridge unit that is attachable to and detachable from the body unit, the cartridge unit including a medicinal-solution reservoir that accommodates at least a medicinal solution and feeds the medicinal solution toward a medicinal-solution administration side, a power source that causes the drive generator to drive, and a drive transmitter that transmits the drive force generated by the drive generator to the medicinal-solution reservoir to push out the medicinal solution in the medicinal-solution reservoir.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of PCT international application Ser. No. PCT/JP2009/055689 filed on Mar. 23, 2009 which designates the United States, incorporated herein by reference, and which claims the benefit of priority from Japanese Patent Application No. 2008-076726, filed on Mar. 24, 2008, incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a medicinal-solution administration device that administers a medicinal solution, such as an anticancer agent, continuously and directly to a treatment target, such as a diseased part, over a relatively long period of time. 
     2. Description of the Related Art 
     Conventionally, an osmotic pump has been used to administer a medicinal solution of a small amount of about 10 ml in a continuous manner over a relatively long and predetermined period of, for example, about one week (see, Theewes F and Yum S I. Principles of the Design and Operation of Generic Osmotic Pumps for the Delivery of Semisolid or Liquid Drug Formulations. Ann Biomed Eng 1976, 4(4):343-353). 
     SUMMARY OF THE INVENTION 
     A medicinal-solution administration device according to an aspect of the invention includes: a body unit including a drive generator that generates a drive force; and a cartridge unit that is attachable to and detachable from the body unit, the cartridge unit including a medicinal-solution reservoir that accommodates at least a medicinal solution and feeds the medicinal solution toward a medicinal-solution administration side, a power source that causes the drive generator to drive, and a drive transmitter that transmits the drive force generated by the drive generator to the medicinal-solution reservoir to push out the medicinal solution in the medicinal-solution reservoir. 
     The above and other features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram illustrating a state in which a medicinal-solution administration device according to a first embodiment of the present invention is applied to a living body; 
         FIG. 2  is an exploded perspective view of the medicinal-solution administration device illustrated in  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 1 ; 
         FIG. 4  is an exploded cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 1 ; 
         FIG. 5  is an exploded perspective view of a medicinal-solution administration device according to a second embodiment of the present invention; 
         FIG. 6  is a cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 5 ; 
         FIG. 7  is an exploded cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 5 ; 
         FIG. 8  is an exploded perspective view of a medicinal-solution administration device according to a third embodiment of the present invention; 
         FIG. 9  is a cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 8 ; 
         FIG. 10  is an exploded cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 8 ; 
         FIG. 11  is an exploded cross-sectional view of a configuration in which a battery is mounted on a medicinal-solution reservoir side; and 
         FIG. 12  is an exploded perspective view of a configuration in which a Perista Pump that directly discharges a medicinal solution is used as a driver. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Exemplary embodiments of a medicinal-solution administration device according to the present invention will be described in detail below with reference to the accompanying drawings. The present invention is not limited to the following embodiments. 
     First Embodiment 
       FIG. 1  is a diagram illustrating a state in which a medicinal-solution administration device according to a first embodiment of the present invention is applied to a living body such as a human body. In  FIG. 1 , a medicinal-solution administration device  1  includes a cannula  1   b  and a medicinal-solution unit  1   a . The cannula  1   b  is configured such that a cannula body having a tip portion for guiding a medicinal solution to a treatment target  2 , which is a diseased part such as a cancer, is implanted into a living body  3 , and a base portion is placed on a body surface S of the living body  3 . The medicinal-solution unit  1   a  is detachably attached to a base portion  25  of the cannula  1   b,  and delivers a medicinal solution to the cannula  1   b . The medicinal-solution administration device  1  continuously and intensively discharges and administers a medicinal solution of about a few ml, e.g., an anticancer agent such as fluorouracil (5-FU), to the treatment target  2  such as a cancer inside the living body  3  over a relatively long period of, e.g., about one week. 
       FIG. 2  is an exploded perspective view of the medicinal-solution administration device  1  illustrated in  FIG. 1 .  FIG. 3  is a cross-sectional view of the medicinal-solution administration device  1  illustrated in  FIG. 1 .  FIG. 4  is an exploded cross-sectional view of the medicinal-solution administration device  1  illustrated in  FIG. 1 . In  FIGS. 2 to 4 , the medicinal-solution administration device  1  mainly includes the medicinal-solution unit  1   a  and the cannula  1   b  as described above. The medicinal-solution unit  1   a  includes a medicinal-solution reservoir  10 , which is substantially cylindrical, and a drive body unit  30  (driver) covered by a casing, which is substantially cylindrical. The medicinal-solution reservoir  10  is formed such that a pipe in the form of either a loop or a coil, which is a continuous loop, is tightly and doubly wound, and a medicinal solution is accommodated in the pipe. The drive body unit  30  includes a drive-liquid unit  11 , a driving unit  20 , and the base portion  25 . The drive-liquid unit  11  is positioned in an internal space of the medicinal-solution reservoir  10  in the form of a cylinder, is covered by a casing in the form of a substantial cylinder, and includes at least a drive-liquid reservoir  12  accommodating a drive liquid (drive transmitter) for pushing out the medicinal solution. The driving unit  20  includes a pump  27  (drive generator). The pump  27  is positioned in an internal space of the medicinal-solution reservoir  10 , and arranged adjacent to the drive-liquid unit  11 . The pump  27  is realized by, for example, an electro-osmotic pump that pushes out a drive liquid for pushing out the medicinal solution. 
     The drive-liquid unit  11 , the driving unit  20 , and the base portion  25  are substantially columnar, and integrally assembled in this order toward the cannula  1   b  side along an axial direction of a cylindrical internal space formed by the medicinal-solution reservoir  10 . The drive body unit  30  functions as a driver that pushes out a medicinal solution in the medicinal-solution reservoir  10 . The medicinal-solution reservoir  10  is detachably attached to the drive body unit  30 . 
     When assembled, the drive-liquid reservoir  12  in the drive-liquid unit  11  is connected to the pump  27  of the driving unit  20  through a drive-liquid intake portion  22  arranged in the substantial center of the driving unit  20 . At an intake of the drive-liquid intake portion  22  is arranged a filter  22   a  for preventing particles from being mixed into the drive liquid. An output side of the pump  27  in the driving unit  20  is connected to an input side of the medicinal-solution reservoir  10  via a flow channel F 21  in the driving unit  20 , a drive-liquid discharging portion  21 , and a flow channel F 11  in the drive-liquid unit  11 . In  FIG. 3 , the pipe of the medicinal-solution reservoir  10  runs from an upper outer side on the upper right→a lower outer side→a lower inner side→an upper inner side on the upper left. A medicinal solution in the medicinal-solution reservoir  10  is pushed out by the drive liquid introduced into the medicinal-solution reservoir  10 . The pushed-out medicinal solution is delivered to the cannula  1   b  via a flow channel F 12  in the drive body unit  30 , and a medicinal-solution receiving portion  23  and a flow channel F 22  in the base portion  25 . The medicinal-solution receiving portion  23  and the flow channel F 12  are connected to each other at the time of assembling. In the medicinal-solution receiving portion  23  is arranged a one-way valve  23   a  functioning as a check valve that prevents, when the medicinal-solution reservoir  10  is detached, back-flow of a medicinal solution from the living body  3  side due to high pressure inside the body. 
     A pump driving unit  26  that controls drive of the pump  27  is arranged in the driving unit  20 . A battery  13  is mounted on the top of the drive-liquid unit  11 . An electrode  24  is arranged on a joint surface of the driving unit  20 , on which the drive-liquid unit  11  is joined. Energy supplied by the battery  13  is supplied to at least the pump driving unit  26  via the electrode  24 . 
     As described above, the pump  27  realized by the electro-osmotic pump that pushes out the drive liquid for pushing out the medicinal solution is arranged between the drive-liquid reservoir  12  and the medicinal-solution reservoir  10 . The operating principle of the electro-osmotic pump is such that the surfaces inside fine pores of an electro-osmotic material (porous material) are charged negatively, excessive positive ions are present in the vicinity of the surfaces, and the positive ions are caused to move because they are subjected to a force due to an electric field applied from the outside, so that the drive liquid is caused to flow, whereby the drive liquid is discharged. Therefore, a discharge amount of the drive liquid can be changed by changing the intensity of the electric field. The drive-liquid unit has a replenishing unit not illustrated, so that the drive liquid can be replenished from the outside via the replenishing unit. It is desirable to use ultrapure water and the like as the drive liquid. 
     The pump  27  obtains the drive liquid from the drive-liquid reservoir  12 , and pushes out the drive liquid to the medicinal-solution reservoir  10  to thereby indirectly pushes the medicinal solution to the cannula  1   b  outside the medicinal-solution reservoir  10 . An air layer or oil is filled between the drive liquid and the medicinal solution to separate the drive liquid and the medicinal solution from each other in order to prevent mixture. 
     The above-mentioned medicinal-solution reservoir  10  is detachably attached to the drive body unit  30 . The medicinal-solution reservoir  10  and the drive body unit  30  are combined with each other by a drive-liquid connection portion  31  and a medicinal-solution connection portion  32  that combine an inlet and an outlet of the medicinal-solution reservoir  10 , and an inner wall of the medicinal-solution reservoir  10  functions as a guide for attachment to and detachment from the drive body unit  30 . The drive-liquid connection portion  31  on the medicinal-solution reservoir  10  side is detachably connected to the flow channel F 11  of the drive body unit  30 . The medicinal-solution connection portion  32  on the medicinal-solution reservoir  10  side is detachably connected to the flow channel F 12  of the drive body unit  30 . The medicinal solution in the medicinal-solution reservoir  10  is consumable supplies, and is replaced by replacing the medicinal-solution reservoir  10  as a whole as an integrated cartridge. In particular, even when the cannula  1   b  is implanted into the living body  3 , it is possible to replace only the medicinal-solution reservoir  10 , so that the medicinal solution can be administered continuously. 
     The medicinal-solution reservoir  10  includes an information input unit  33  for inputting medicinal-solution administration information, which is medicinal-solution administration information related to an administration amount of the medicinal solution and is specific to the medicinal-solution reservoir. The drive body unit  30  includes an information detecting unit  34  that detects the medicinal-solution administration information input by the information input unit  33 . The information input unit  33  includes three protrusions for representing the medicinal-solution administration information on the accommodated medicinal solution by three-bit information, and is arranged on the internal space side of the medicinal-solution reservoir  10 . Examples of the medicinal-solution administration information include, but not limited to, a standard administration amount of the medicinal solution per unit time (ml/h), a maximum administration amount, and an effective amount of the medicinal solution. Furthermore, the information input unit  33  may be embodied in various forms other than the three protrusions. On the other hand, the information detecting unit  34  includes detecting portions for detecting the three-bit information corresponding to the three protrusions. When the medicinal-solution reservoir  10  is attached to the drive body unit  30 , respective bit-corresponding positions of the information input unit  33  and the information detecting unit  34  are combined with each other by using the medicinal-solution connection portion  32  and the drive-liquid connection portion  31  as positioning mechanisms in circumferential directions. 
     The medicinal-solution administration information represents information on the administration amount of the medicinal solution by three bits, and the information detected by the information detecting unit  34  is input to the pump driving unit  26  via the electrode  24 . The pump driving unit  26  controls the pump  27  based on the input medicinal-solution administration information to thereby control the administration amount of the medicinal solution. The medicinal-solution administration information may be information indicating time profile information related to the administration amount of the medicinal solution. In this case, it is preferable that the pump driving unit  26  stores detailed medicinal-solution administration amount information corresponding to the bit information being the input medicinal-solution administration amount information. Although the above-mentioned three bits indicate the eight types of medicinal-solution administration information, the present invention is not limited to this example. It is possible to include an information input unit and an information detecting unit for handling the increased number of bits. Furthermore, it is possible to input the medicinal-solution administration information by using a configuration in which the mounting position of the medicinal-solution connection portion  32  or the drive-liquid connection portion  31  is adjusted to the protrusion position (bit position) of the information input unit  33 . While the information input unit  33  and the information detecting unit  34  described above are physically contacted with each other to input the medicinal-solution administration information, it is possible to input the medicinal-solution administration information by electrical contact. Furthermore, it is possible to arrange a memory chip or a bit switch for storing the bit information representing the medicinal-solution administration information onto the medicinal-solution reservoir  10  side and to cause the pump driving unit  26  to read the bit information by electrical contact when the medicinal-solution reservoir  10  is attached. Namely, any configurations may be applied as long as the medicinal-solution administration information can be input by attaching the medicinal-solution reservoir  10 . Thus, according to the embodiment, it is possible to replace the medicinal solution and cope with a new required amount when a type of the medicinal solution is changed, in contrast to a conventional osmotic pump that has difficulty with replacement of the medicinal solution. Furthermore, as described above, because the medicinal-solution reservoir  10  is provided with the medicinal-solution administration information, it is possible to prevent a failure to set the amount caused by a human error when the medicinal solution is replaced. 
     According to the first embodiment, the medicinal-solution reservoir  10  is detachably attached to the drive body unit  30 , so that it is possible to replace the medicinal-solution reservoir  10 . Therefore, even with a medicinal-solution administration device having the drive body unit  30  that variably controls the administration amount of the medicinal solution by using a drive liquid, it is possible to easily replace the medicinal solution as consumable supplies. 
     Second Embodiment 
     Next, a second embodiment of the present invention is explained. In the embodiment described above, only the medicinal-solution reservoir  10  is detachable. However, in the second embodiment, the medicinal-solution reservoir  10  and the drive-liquid unit  11  are integrated with each other so that not only the medicinal solution but also the drive liquid can be replaced together with the medicinal solution. In other words, the drive-liquid unit  11  is arranged not on the drive body unit  30  (driver) side but on the medicinal-solution reservoir  10  side. The medicinal-solution reservoir  10  and the drive-liquid unit  11  integrated with each other are detachably attached to the drive body unit  30 . 
       FIG. 5  is an exploded perspective view of a medicinal-solution administration device according to the second embodiment of the present invention.  FIG. 6  is a cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 5 .  FIG. 7  is an exploded cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 5 . In  FIGS. 5 to 7 , in the medicinal-solution administration device, a medicinal-solution combining portion  43 , which is inserted in the flow channel F 12 , is provided on the driving unit  20  side so that the drive-liquid unit  11  and the driving unit  20  can be detached from each other. Furthermore, the medicinal-solution reservoir  10  and the drive-liquid unit  11  are integrated with each other. In the second embodiment, the medicinal-solution connection portion  32  and the drive-liquid connection portion  31  described in the first embodiment are removed, and the inlet and the outlet of the medicinal-solution reservoir  10  are directly connected to the flow channels F 11  and F 12 , respectively. Other configurations are the same as those of the first embodiment. 
     A medicinal-solution driving unit  41  that includes the medicinal-solution reservoir  10  and the drive-liquid unit  11  integrated with each other is detachably attached to the driving unit  20 . The medicinal-solution administration information similar to that of the first embodiment is set when the medicinal-solution driving unit  41  is integrally formed, and is input to the driving unit  20  side via the electrode  24 . It is of course possible to arrange a mechanism corresponding to the information input unit between the drive-liquid unit  11  and the driving unit  20 , and a mechanism corresponding to the information detecting unit between the medicinal-solution reservoir  10  and the driving unit  20 . 
     According to the second embodiment, because the medicinal-solution reservoir  10  and the drive-liquid unit  11  are integrated with each other and they are detachable, it is possible to easily replace consumable supplies, such as the medicinal solution in the medicinal-solution reservoir  10 , the drive liquid in the drive-liquid unit  11 , and the battery  13 , in an integrated manner. 
     Third Embodiment 
     Next, a third embodiment of the present invention is explained. In the first embodiment described above, only the medicinal-solution reservoir  10  is detachable, and, in the second embodiment described above, the medicinal-solution reservoir  10  and the drive-liquid unit  11  are detachable. In contrast, in the third embodiment, the medicinal-solution reservoir  10  and the drive-liquid unit  11  are formed such that they are independently detachable. 
       FIG. 8  is an exploded perspective view of a medicinal-solution administration device according to the third embodiment of the present invention.  FIG. 9  is a cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 8 .  FIG. 10  is an exploded cross-sectional view of the medicinal-solution administration device illustrated in  FIG. 8 . In  FIGS. 8 to 10 , the medicinal-solution administration device is formed such that the medicinal-solution connection portion  32  and the drive-liquid connection portion  31  described in the first embodiment are added to the configuration of the second embodiment, and the medicinal-solution reservoir  10  is detachably attached to the drive-liquid unit  11 . 
     In the third embodiment, because the medicinal-solution reservoir  10  and the drive-liquid unit  11  are independently detachable, it is possible to flexibly and easily replace arbitrary consumable supplies. 
     In the first and the third embodiments described above, the battery  13  is mounted on the drive-liquid unit  11  side; however, it is not limited thereto. It is possible to mount the battery  13  on the medicinal-solution reservoir  10  side as illustrated in  FIG. 11 . In this configuration, particularly when only the medicinal-solution reservoir  10  is detachable as described in the first embodiment, it is possible to appropriately replace the battery as consumable supplies. 
     Furthermore, in the first to the third embodiments described above, the electro-osmotic pump is used as an example; however, it is not limited thereto. It is possible to use other types of pumps, e.g., a Perista Pump, as the driver. In this case, because the Perista Pump can directly discharge the medicinal solution, it is possible to omit the drive-liquid unit  11  from the configuration. For example, as illustrated in  FIG. 12 , it is possible to cause a drive body unit  130  realized by the Perista Pump to discharge the medicinal solution in the detachable medicinal-solution reservoir  10  to the cannula  1   b . In this case, the drive body unit (driver)  130  may be configured such that an eccentric cam (drive transmitter) is attached to an axis of a rotary motor (drive generator), and the medicinal-solution reservoir may be configured in a tube structure as a pipeline arranged in a loop shape. In this case, it is possible to realize a mechanism in which the eccentric cam that is driven along with the rotation of the rotary motor pushes to deform the loop-shaped tube from the outside so that the medicinal solution contained in the tube is pushed forward. In this manner, when the driver for driving the medicinal solution is arranged inside the loop of the loop-shaped pipeline in a geometrical arrangement, a compact design can be achieved. The medicinal-solution reservoir may be arranged on portions other than the inside of the driver. For example, the medicinal-solution reservoir may be arranged on the top portion. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.