Abstract:
The foreign matter capture instrument includes: a first manipulation wire; framework wire materials, the base end parts being coupled to a leading end part of the first manipulation wire, and the leading end parts being respectively bundled together; and a second manipulation wire which is coupled to the leading end parts of the framework wire materials, separates from the first manipulation wire extending toward the base end side of the first manipulation wire. By moving the first manipulation wire toward the leading end side relative to the second manipulation wire, the framework wire materials expand and configure a basket, and by further relatively moving the first manipulation wire toward the leading end side, the basket becomes shallower.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a body-cavity foreign object capturing device for capturing a foreign object which is produced in a body cavity of the human body, such as a tubular organ. 
       BACKGROUND ART 
       [0002]    A foreign object such as a gallstone, a pancreatic stone, or a thrombus is sometimes produced in a tubular organ such as the bile duct, the pancreatic duct, the ureter, a blood vessel, or another body cavity of the human body. Therefore, an operation of capturing such a foreign object and removing it from a body cavity is performed. 
         [0003]    For example, Patent Literature 1 discloses a treatment tool for a tubular organ, including: a tube; a wire which is inserted through the tube; a basket which is formed into a tubular shape by knitting metal wire members, and in which base end portions thereof are bundled together and coupled to a distal end portion of the tube, and distal end portions are bundled and coupled to a distal end portion of the wire; and a handle portion which holds a base end portion of the tube, and which holds a base end portion of the wire in a manner that the wire is movable relative to the tube. 
         [0004]    The basket has an approximate spindle shape in which the ends of the tubular member are reduced in diameter into a tapered shape. In the basket, the wire is placed in the middle, the distal end side has a mesh shape formed by plural metal wire members, the plural metal wire members are bundled together to form plural bundled portions in the base end side, and openings are formed between them. 
         [0005]    In an actual use of the treatment tool, the handle portion is operated to pull the wire toward the proximal side to expand the diameter of the basket, a foreign object is received through the opening to be captured, the basket is then moved to the duodenum or the like, the handle portion is operated in the position to push and pull the wire, thereby expanding and contracting the diameter of the basket, and the foreign object is discharged through the opening of the basket. 
       CITATION LIST 
     Patent Literature 
     Patent Literature 1 
       [0000]    
       
         WO-2009-150920-A 
       
     
       SUMMARY OF INVENTION 
     Problem to be Solved by Invention 
       [0007]    In the case of the treatment tool of Patent Literature 1, however, the wire is placed in the center of the basket. When the diameter of the basket is expanded for receiving a foreign object through the opening, therefore, the wire serves as an obstacle, and a foreign object which is relatively large, such as a gallstone is sometimes hardly captured. 
         [0008]    In a tubular organ such as the bile duct, plural stones are sometimes produced in a line along the path of the tubular organ (referred to as stacked stones or the like). In this case, with a structure for capturing a foreign object by expanding the diameter of a basket as employed in the above-described treatment tool, the diameter of the basket is contracted, the basket is passed between the stones and the tubular organ, and placed in front of the leading stone, and then the diameter of the basket is expanded and pulled to the proximal side, thereby capturing the plural stones. However, it is not easy to collectively capture plural relatively-large stones. The stones may get stuck in the middle of the tubular organ, and may not be taken out. 
         [0009]    An object of the invention is to provide a body-cavity foreign object capturing device which can easily capture even a relatively-large foreign object. 
       Solution to Problem 
       [0010]    In order to attain the object, the present invention provides 
         [0011]    a body-cavity foreign object capturing device including: 
         [0012]    a first operation wire; 
         [0013]    plural framework wire members, base end portions of which are coupled to a distal end portion of the first operation wire, and distal end portions of which are bundled together; and 
         [0014]    a second operation wire which is coupled to the distal end portions of the plural framework wire members, which extends toward a base end of the first operation wire while being separated from the first operation wire, and which is operable independently from the first operation wire. 
         [0015]    There may be preferably provided, 
         [0016]    the body-cavity foreign object capturing device, 
         [0017]    wherein the second operation wire is caused to have a curved shape as a free-state initial shape as viewed from an axial distal end side. 
         [0018]    There may be preferably provided, 
         [0019]    the body-cavity foreign object capturing device, 
         [0020]    wherein the second operation wire is configured to expand in an outer radial direction by moving the second operation wire relative to the first operation wire toward the distal end, and to move to the distal end side with respect to a coupling portion between the distal ends of the plural framework wire members and the distal end of the second operation wire by further relatively moving the second operation wire toward the distal end. 
         [0021]    There may be preferably provided, 
         [0022]    the body-cavity foreign object capturing device, 
         [0023]    wherein the framework wire members are configured to expand to form a basket by moving the first operation wire relative to the second operation wire toward the distal end, and a depth of the basket is reduced by further relatively moving the first operation wire toward the distal end. 
         [0024]    There may be preferably provided, 
         [0025]    the body-cavity foreign object capturing device, 
         [0026]    wherein a resin membrane is disposed in a portion of the basket, 
         [0027]    wherein the portion ranging from a coupling portion between distal end portions of the plural framework wire members and a distal end portion of the second operation wire, to a portion where a diameter of the basket is maximally expanded. 
         [0028]    There may be preferably provided, 
         [0029]    the body-cavity foreign object capturing device, 
         [0030]    wherein the plural framework wire members are placed at predetermined intervals along a circumferential direction thereof in a state where the diameter of the basket is expanded, 
         [0031]    wherein the second operation wire is configured by a single wire, and placed in a position circumferentially opposed to a portion where the plural framework wire members are placed in the state where the diameter of the basket is expanded, and 
         [0032]    wherein an interval between the second operation wire and one of the framework wire members which is closest to the second operation wire is wider than intervals among the plural framework wire members. 
       Advantageous Effects of Invention 
       [0033]    According to the invention, the second operation wire is caused to tangle with a foreign object in a body cavity by moving the second operation wire relative to the first operation wire toward the distal end, and the foreign object can be captured by interposing the foreign object between the plural framework wire members which are coupled to the first operation wire, and the second operation wire, and then taken out from the body cavity. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0034]      FIG. 1  is a perspective view showing an embodiment of the body-cavity foreign object capturing device according to the invention. 
           [0035]      FIG. 2  is a side view diagram of the foreign object capturing device. 
           [0036]      FIG. 3  is a main-portion enlarged diagram of the foreign object capturing device, as viewed along arrow line A in  FIG. 2 . 
           [0037]      FIG. 4  is a main-portion enlarged diagram of the foreign object capturing device, as viewed along arrow line B-B in  FIG. 2 . 
           [0038]      FIG. 5  is a side view diagram of a state where a basket is accommodated in a distal end portion of a catheter, and showing an operation of the foreign object capturing device. 
           [0039]      FIG. 6  is a side view diagram of a state where the diameter of the basket is expanded in the state of  FIG. 2 , and showing an operation of the foreign object capturing device. 
           [0040]      FIG. 7  is a side view diagram of a state where the diameter of the basket is expanded in the state of  FIG. 6 , and showing an operation of the foreign object capturing device. 
           [0041]      FIG. 8  is a side view diagram of a state where the diameter of the basket is further expanded in the state of  FIG. 7 , and showing an operation of the foreign object capturing device. 
           [0042]      FIG. 9  is a side view diagram of a state where the diameter of the basket is further expanded in the state of  FIG. 8 , and showing an operation of the foreign object capturing device. 
           [0043]      FIG. 10  is a diagram showing a first use state of the foreign object capturing device. 
           [0044]      FIG. 11  is a diagram showing a second use state of the foreign object capturing device. 
           [0045]      FIG. 12  is a diagram showing a third use state of the foreign object capturing device. 
           [0046]      FIG. 13  is a diagram showing a fourth use state of the foreign object capturing device. 
           [0047]      FIG. 14  is a side view diagram showing another embodiment of the body-cavity foreign object capturing device according to the invention. 
           [0048]      FIG. 15  is a main-portion enlarged perspective view of the foreign object capturing device in a state where a second operation wire is in a free state. 
           [0049]      FIG. 16  is a main-portion enlarged perspective view of the foreign object capturing device in a state where the second operation wire is moved toward distal end. 
           [0050]      FIGS. 17A and 17B  show the foreign object capturing device as viewed from the axial distal end side.  FIG. 17A  is a diagram of a case where the second operation wire is in the free state.  FIG. 17B  is a diagram in a state where the second operation wire is moved toward the distal end. 
           [0051]      FIGS. 18A and 18B  show an operation of the foreign object capturing device.  FIG. 18A  is a side view diagram of a case where the second operation wire is moved toward the distal end in the state of  FIG. 14 .  FIG. 18B  is a side view diagram of a case where the second operation wire is moved toward the distal end in the state of  FIG. 18A . 
           [0052]      FIGS. 19A and 19B  show an operation of the foreign object capturing device.  FIG. 19A  is a side view diagram of a case where the second operation wire is moved toward the distal end in the state of  FIG. 18A .  FIG. 19B  is a side view diagram of a case where the second operation wire is moved toward the distal end in the state of  FIG. 19B . 
           [0053]      FIG. 20  is a diagram showing a use state of the foreign object capturing device. 
           [0054]      FIGS. 21A and 21B  show another structure of the second operation wire in the foreign object capturing device as viewed from the axial distal end side.  FIG. 21A  is a diagram of a case where the second operation wire is in the free state.  FIG. 21B  is a diagram of a state where the second operation wire is moved toward the distal end. 
           [0055]      FIGS. 22A and 22B  show a further structure of the second operation wire in the foreign object capturing device as viewed from the axial distal end side.  FIG. 22A  is a diagram of a case where the second operation wire is in the free state.  FIG. 22B  is a diagram of a state where the second operation wire is moved toward the distal end. 
           [0056]      FIG. 23  is a photograph of an example of the foreign object capturing device, and showing a first use state of the example. 
           [0057]      FIG. 24  is a photograph of a second use state of the foreign object capturing device. 
           [0058]      FIG. 25  is a photograph of a third use state of the foreign object capturing device. 
           [0059]      FIG. 26  is a photograph of a fourth use state of the foreign object capturing device. 
           [0060]      FIG. 27  is a photograph of a fifth use state of the foreign object capturing device. 
           [0061]      FIG. 28  is a photograph of a sixth use state of the foreign object capturing device. 
           [0062]      FIG. 29  is a photograph of a seventh use state of the foreign object capturing device. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0063]    Hereinafter, an embodiment of a body-cavity foreign object capturing device according to the invention will be described with reference to  FIGS. 1 to 13 . 
         [0064]    As shown in  FIGS. 1 and 2 , a body-cavity foreign object capturing device (hereinafter, referred to as “foreign object capturing device  10 ”) of the embodiment has a first operation wire  15 , plural framework wire members  20 , and a second operation wire  25 . 
         [0065]    The base end portions of the plural framework wire members  20  are placed on the outer circumference of a distal end portion of the first operation wire  15 , and coupled to the outer circumference of the distal end portion of the first operation wire  15  by squeezing a cylindrical coupling member  16  which is placed on the outer circumference thereof. 
         [0066]    The distal end portion of the second operation wire  25  is bundled with distal end portions of the plural framework wire members  20 , and coupled to the distal end portions of the plural framework wire members  20  by squeezing a cylindrical bundling member  22  placed on the outer circumference thereof. The second operation wire  25  extends toward the base end of the first operation wire  15  while being separated from the first operation wire  15 , and is operable independently from the first operation wire  15 . 
         [0067]    In the embodiment, a basket  30  is configured such that the plural framework wire members  20  is expandable by moving the first operation wire  15  relative to the second operation wire  25  toward the distal end (see  FIGS. 1 and 2 ) for capturing foreign objects G (see  FIG. 10 ). 
         [0068]    The term “moving the first operation wire  15  relative to the second operation wire  25  toward the distal end” includes operations such as (1) the second operation wire  25  is fixed, and the first operation wire  15  is pushed toward the distal end, (2) the first operation wire  15  is fixed, and the second operation wire  25  is pulled toward the base end, and (3) the first operation wire  15  is pushed toward the distal end, and the second operation wire  25  is pulled toward the base end. 
         [0069]    The coupling between the base end portions of the framework wire members  20  and the distal end portion of the first operation wire  15 , and that between the distal end portions of the framework wire members  20  and the distal end portion of the second operation wire  25  may be performed by, for example, an adhesive agent, brazing, soldering, or a string-like member, and are not particularly limited. 
         [0070]    Referring also to  FIGS. 3 and 4 , the framework wire members  20  in the embodiment are placed, in a state where the diameter of the basket  30  is expanded, in a plural number at predetermined intervals along the circumferential direction thereof. In the embodiment, three framework wire members  20  are placed at uniform intervals W 1  (see  FIG. 4 ) in the circumferential direction. However, the placement manner is not limited to this. The interval W 1  in the state where the diameter of the basket  30  is expanded is varied depending on a place in the body where the foreign object capturing device  10  is to be used. Usually, the interval is preferably 3 to 20 mm, more preferably 3 to 15 mm 
         [0071]    Each of the framework wire members  20  is formed by a wire member which is thinner than the second operation wire  25  (see  FIGS. 3 and 4 ). Specifically, the outer diameter of the framework wire member  20  is preferably 0.02 to 0.1 mm, more preferably 0.05 to 0.1 mm 
         [0072]    The number of the framework wire members  20  is preferably 2 to 4, more preferably 2 or 3. 
         [0073]    On the other hand, the second operation wire  25  in the embodiment is configured by a single wire member, and placed in a position circumferentially opposed to a portion where the plural framework wire members  20  are placed in the state where the diameter of the basket  30  is expanded (see  FIGS. 3 and 4 ). 
         [0074]    The interval W 2  (see  FIG. 4 ) between the second operation wire  25  and the framework wire member  20  which is closest to the second operation wire  25  is wider than the intervals W 1  between adjacent framework wire members  20 ,  20 . The interval W 2  in the state where the diameter of the basket  30  is expanded is varied depending on a place in the body where the foreign object capturing device  10  is to be used. Usually, the interval is preferably 5 to 30 mm, more preferably 10 to 25 mm 
         [0075]    The number of the second operation wire  25  is not limited to one. Plural wires may be bundled together and placed, and the placement interval is not limited to the above-described manner. In the case where the second operation wire  25  is configured by a single wire member, the outer diameter is preferably 0.05 to 0.2 mm, more preferably 0.05 to 0.15 mm 
         [0076]    The basket  30  shown in  FIG. 2  is configured so that the depth of the basket  30  is reduced by further moving the first operation wire  15  relative to the second operation wire  25  toward the distal end (see  FIGS. 6 to 9 ). The depth of the basket  30  means the axial length from the coupling portion between the distal end portions of the plural framework wire members  20  and the distal end portion of the second operation wire  25 , to a portion where the diameter of the basket  30  is maximally expanded. 
         [0077]    The first operation wire  15 , the second operation wire  25 , and the framework wire members  20  are formed by, for example, stainless steel, Ta, Ti, Pt, Au, W, or a shape memory alloy such as a Ni—Ti based alloy, a Co—Cr based alloy, a Co—Cr—Ni based alloy, a Cu—Zn—X (X=Al, Fe, etc.) based alloy, or a Ni—Ti—X (X=Fe, Cu, V, Co, etc.) based alloy. The coupling member  16  and the bundling member  22  are formed by a radiopaque metal, for example, Pt, Ti, Pd, Rh, Au, W, or an alloy thereof. 
         [0078]    The basket  30  is preferably configured such that the plural framework wire members  20  are previously shaped so as to form an approximate spindle shape as shown in  FIG. 2  in cooperation with the second operation wire  25 , whereby the distal and base end sides are contracted, and the diameter of a portion that is close to the axial base end is expanded. More preferably, the above-described shape memory alloy is used as the framework wire members  20 , and a shape memory process is performed so as to cause it to memorize the above-described shape. 
         [0079]    A resin membrane  35  is disposed in a portion of the basket  30  which ranges from the coupling portion between the distal end portions of the plural framework wire members  20  and the distal end portion of the second operation wire  25 , to the portion where the diameter of the basket  30  is maximally expanded. In the embodiment, the resin membrane  35  is disposed so as to cover the portion between the plural framework wire members  20  and the second operation wire  25 , and has a bag-like shape in which the distal end side is closed, the diameter is gradually expanded as advancing toward the base end side, and the base end side is opened, and the diameter is expanded in accordance with the expansion of the diameter of the basket  30 . Even in the case where the foreign object G received through the opening of the basket  30  is relatively small, the resin membrane  35  enables the foreign object to be captured so as not to be discharged gaps from between the plural framework wire members  20  and the second operation wire  25 . 
         [0080]    The resin membrane  35  in the embodiment is configured so as to cover the outer circumferences of the framework wire members  20  and the second operation wire  25  (a state where the framework wire members  20  and the second operation wire  25  are so to speak embedded in the resin membrane  35 ). However, the mode of the membrane is not limited to this. Plural minute holes for allowing a fluid to pass therethrough and having a size which does not allow the foreign objects G to pass may be disposed in the resin membrane  35 . 
         [0081]    As the material of the resin membrane  35 , for example, polyurethane such as polyether-based polyurethane, polyester-based polyurethane, polycarbonate-based polyurethane, or polycaprolactone-based polyurethane, polyurethane elastomer, nylon, nylon elastomer, olefin-based elastomer including polybutadiene and the like, styrene-based elastomer, silicone, polyimide-based resin, polyether ketone, or polyether ether ketone may be employed. Among them, polyurethane is preferably employed. 
         [0082]    The resin membrane  35  can be formed by, for example, casting a polymer solution in a state where the plural framework wire members  20  are previously set in molds, or setting the plural framework wire members  20  in molds, and then dipping the molds in a polymer solution. 
         [0083]    In the foreign object capturing device  10  of the embodiment, as shown in  FIG. 2 , a catheter  45  is placed on the outer circumferences of the first operation wire  15  and the second operation wire  25  other than the distal end portions. Moreover, an operation handle  40  for operating the first operation wire  15  and the second operation wire  25  independently from each other is placed on the base end side of the catheter  45 . 
         [0084]    The catheter  45  in the embodiment is a so-called single-lumen catheter in which one lumen is disposed in a range from the base end to the distal end as shown in  FIG. 2 . Alternatively, plural lumens may be disposed. The lumen structure is not particularly limited. In the case where two lumens are disposed, for example, the first operation wire  15  is passed through a predetermined one of the lumens, and the second operation wire  25  is passed through the other lumen, thereby causing the first operation wire  15  and the second operation wire  25  not to tangle with each other, and the operability can be improved. 
         [0085]    In the operation handle  40 , as shown in  FIGS. 1 and 2 , a first slider  41  is attached to a distal end side thereof through a slit  41   a  so as to be anteroposteriorly slidable in the axial direction of the operation handle  40 , and a second slider  42  is attached to a position adjacent to the first slider  41  through a slit  42   a  so as to be anteroposteriorly slidable in the axial direction of the operation handle  40 . The base end portion of the first operation wire  15  is connected to the first slider  41  through a through hole which is formed in the operation handle  40 , and which is not shown, and on the other hand the base end portion of the second operation wire  25  is connected to the second slider  42  through a through hole which is not shown. 
         [0086]    As shown in  FIG. 5 , a tubular portion  43  which has a slightly small outer diameter extends from the distal end side of the operation handle  40 , and a slide member  44  which is slidable with respect to the tubular portion  43 , and which has a tapered cylindrical shape is attached to the outer circumference of the tubular portion  43 . A base end portion of the catheter  45  is coupled to the slide member  44 . When the slide member  44  is slid toward the distal end of the tubular portion  43 , therefore, the catheter  45  is pushed out, and the framework wire members  20  are linearly stretched to reduce the diameter so that the basket  30  is accommodated in the inner circumference of a distal end portion of the catheter  45  (see  FIG. 5 ). 
         [0087]    Although not illustrated, it is preferable that, for example, an engagement button is disposed in the slide member  44 , on the other hand an engagement recess which is engageable with the engagement button is disposed in the distal end of the tubular portion  43 , and, when the slide member  44  is slid toward the base end of the tubular portion  43 , the engagement button is engaged with the engagement recess to restrict the sliding operation of the slide member  44 . 
         [0088]    In a state where the diameter of the basket  30  is expanded as shown in  FIG. 2 , the first slider  41  is placed in a position closer to the base end of the handle, and the second slider  42  is placed in a position closer to the distal end of the handle. 
         [0089]    When, in the diameter-expanded state of the basket  30  shown in  FIG. 2 , the second slider  42  is held, and the first slider  41  is slid toward the distal end, the first operation wire  15  is moved toward the distal end with respect to the second operation wire  25 , and the diameter of the basket  30  is expanded (see  FIG. 6 ). When, in this state, the first slider  41  is further slid toward the distal end, the first operation wire  15  is further moved toward the distal end with respect to the second operation wire  25 , and the diameter of the basket  30  is further expanded (see  FIG. 7 ). 
         [0090]    When, in the above-described state, the first slider  41  is held, and the second slider  42  is slid toward the base end, the second operation wire  25  is moved toward the base end with respect to the first operation wire  15 , and the diameter is largely expanded so that the basket  30  is pressed to have a flat shape (see  FIG. 8 ). When, in this state, the second slider  42  is further slid toward the base end, the second operation wire  25  is further moved toward the base end with respect to the first operation wire  15 , and the diameter is further largely expanded so that a part of the basket  30  rolls back toward the distal end (see  FIG. 9 ). 
         [0091]    The structure and shape of the operation handle  40  are not limited to the above-described mode as far as the first operation wire  15  and the second operation wire  25  are operable independently from each other. 
         [0092]    When, in the diameter-expanded state of the basket  30  shown in  FIG. 2 , the slide member  44  is slid toward the distal end with respect to the tubular portion  43  of the operation handle  40 , the catheter  45  is pushed out, the outer circumference of the basket  30  is pressed, the framework wire members  20  are linearly stretched to reduce the diameter, and the basket  30  is accommodated in the inner circumference of the distal end portion of the catheter  45 . On the other hand, when the slide member  44  is slid toward the base end with respect to the tubular portion  43 , the basket  30  is released from the distal end portion of the catheter  45  to expand the diameter (see  FIG. 2 ). A lumen through which a guide wire  1  (see  FIG. 10 ) can be passed, and which is not shown is disposed in the catheter  45 . 
         [0093]    In the embodiment, the catheter  45  is coupled to the slide member  44  of the operation handle  40 , and the catheter  45  is slid by the sliding operation of the slide member  44 . Alternatively, for example, the operation handle  40  and the catheter  45  may be separately formed, and the catheter  45  may be made independently slidable. Alternatively, a tube, sheath, or the like which is separately formed may be placed on the outer circumference of the catheter  45 , and the basket  30  may be accommodated or released by the sliding operation thereof. 
         [0094]    Next, an example of the method of using the thus configured foreign object capturing device  10  of the invention will be described. 
         [0095]    As shown in  FIG. 10 , the foreign object capturing device  10  of the embodiment can be used for capturing foreign objects G such as gallstones produced in a cavity of the human body, for example, a tubular organ V 2  such as the bile duct, the pancreatic duct, a ureter, a trachea, or a blood vessel such as a brain blood vessel, the thoracic aorta, or the abdominal aorta, and moving the foreign objects G to a tubular organ V 1  having a relatively-large inner diameter such as the duodenum to discharge the foreign objects. The place to which the foreign object capturing device  10  is to be applied is not particularly limited. However, it may be particularly preferably used for discharge a gallstone in the bile duct or a pancreatic stone in the pancreatic duct. 
         [0096]    When the foreign object capturing device  10  is to be used, as shown in  FIG. 5 , the slide member  44  is firstly slid toward the distal end of the tubular portion  43 , the catheter  45  is pushed out to cause the framework wire members  20  to be linearly stretched, and the basket  30  in the diameter-contracted state is accommodated in the inner circumference of the distal end portion of the catheter  45 . 
         [0097]    Then, an endoscope  5  is moved by a well-known method from the oral cavity to the tubular organ V 1  having a large diameter such as the duodenum through the stomach and the like, and a distal end portion of the endoscope  5  is placed in the vicinity of a branch portion N (the papilla) of tubular organs V 2 , V 3 . 
         [0098]    Thereafter, the guide wire  1  is ejected from the distal end opening of the endoscope  5  through the lumen, and inserted into the tubular organ V 2  (bile duct), and the distal end portion is caused to reach a position which is across the portion where the plural foreign objects G exist. Thereafter, the guide wire  1  is inserted into the not-shown lumen of the catheter  45 , the foreign object capturing device  10  is moved along the guide wire  1  under observation through the endoscope  5 , and the distal end portion of the catheter  45  is caused to reach a position which is across the portion where the plural foreign objects G exist. 
         [0099]    When, in the above-described state, the slide member  44  is slid toward the base end with respect to the tubular portion  43  of the operation handle  40 , the basket  30  is released from the distal end portion of the catheter  45 , and the plural framework wire members  20  and the resin membrane  35  are widened to expand the diameter of the basket  30  (see  FIGS. 2 and 10 ). 
         [0100]    When the first slider  41  of the operation handle  40  is slid toward the distal end while holding the second slider  42 , the first operation wire  15  is moved toward the distal end with respect to the second operation wire  25 , and the diameter of the basket  30  is expanded (see  FIG. 6 ). When, in this state, the first slider  41  is further slid toward the distal end, the first operation wire  15  is further moved toward the distal end with respect to the second operation wire  25 , and the diameter of the basket  30  is further expanded (see  FIGS. 7 and 11 ). 
         [0101]    When, in the above-described state, the whole foreign object capturing device  10  is pulled toward the proximal side, the foreign objects G enter through the openings of the basket  30  as shown in  FIG. 11 , and it is possible to capture the foreign objects G 
         [0102]    In the foreign object capturing device  10 , as described above, the basket  30  is configured such that the plural framework wire members  20  is expanded by moving the first operation wire  15  relative to the second operation wire  25  toward the distal end. When, in this state, the whole foreign object capturing device  10  is pulled toward the proximal side, therefore, the foreign objects G enter through the openings of the basket  30  as shown in  FIG. 11 , and it is possible to capture the foreign objects G 
         [0103]    In the embodiment, the plural framework wire members  20  are formed by wire members which are thinner than the second operation wire  25  (see  FIGS. 3 and 4 ), and therefore the diameter of the basket  30  can be easily expanded. 
         [0104]    In the embodiment, moreover, the single second operation wire  25  is placed so as to be circumferentially opposed to the plural framework wire members  20 , and the interval W 2  between the second operation wire  25  and the framework wire member  20  which is closest to the second operation wire  25  is wider than the intervals W 1  between the framework wire members  20 ,  20  (see  FIG. 4 ). Therefore, the diameter of the basket  30  is expanded so that the basket expands in the circumferential direction, the large openings can be ensured, and even a large foreign object can be easily captured. 
         [0105]    After the foreign objects G are captured by the basket  30  as described above, the whole foreign object capturing device  10  is further pulled back toward the proximal side, and the plural framework wire members  20  and the resin membrane  35  are moved to the tubular organ V 1  (for example, the duodenum) having a diameter which is larger than the tubular organ V 2  (see  FIG. 12 ). 
         [0106]    When, in this position, the second slider  42  of the operation handle  40  is slid toward the base end while holding the first slider  41 , the second operation wire  25  is moved toward the base end with respect to the first operation wire  15 , and the diameter is largely expanded so that the basket  30  is pressed to have a flat shape as shown in  FIGS. 8 and 12 . 
         [0107]    When, in this state, the second slider  42  of the operation handle  40  is further slid toward the base end while holding the first slider  41 , the second operation wire  25  is further moved toward the base end with respect to the first operation wire  15 , and the diameter is further largely expanded so that a part of the basket  30  rolls back toward the distal end as shown in  FIGS. 9 and 13 . 
         [0108]    As a result, the foreign objects G captured in the basket  30  can be smoothly pushed out through the openings, and discharged into the tubular organ V 1  as shown in  FIG. 13 . In the case where the foreign objects G cannot be sufficiently discharged by the above-described operation, the diameter of the basket  30  can be expanded and contracted, and the foreign objects G can be discharged from the interior of the resin membrane  35  by, in a state where the first slider  41  of the operation handle  40  is fixed, repeatedly anteroposteriorly sliding the second slider  42  in the axial direction. 
         [0109]    In the embodiment, the resin membrane  35  is disposed in the basket  30 . Even when the foreign objects G are relatively small substances such as fragmentary stones, debris, or plaque, therefore, the foreign objects can be captured without omission. 
         [0110]    When a large foreign object G or a large number of foreign objects G are captured in the basket  30 , there is a possibility that the basket  30  may be caught in a small-inner diameter place (for example, the papilla) in a tubular organ, and may not be taken out. In this case, the resin membrane  35  is broken, and the foreign objects G are discharged. Therefore, the basket  30  can be safely taken out. 
         [0111]      FIGS. 14 to 22  show another embodiment of the body-cavity foreign object capturing device according to invention. Portions which are substantially identical with the above-described embodiment are denoted by the same reference numerals, and their description is omitted. 
         [0112]    As shown in  FIG. 14 , the body-cavity foreign object capturing device  10   a  (hereinafter, referred to as “foreign object capturing device  10   a ”) of the embodiment has: the first operation wire  15 ; the plural framework wire members  20  in which the base end portions are coupled to the distal end portion of the first operation wire  15  through the coupling member  16 , and the distal end portions are bundled together through the bundling member  22 ; and a second operation wire  26  which is coupled to the distal end portions of the plural framework wire members  20  through the bundling member  22 , which extends toward the base end of the first operation wire  15  while being separated from the first operation wire  15 , and which is operable independently from the first operation wire  15 . 
         [0113]    The foreign object capturing device  10   a  of the embodiment has a structure in which the resin membrane  35  is not stretched among the plural framework wire members  20 . In the operation handle  40  in the embodiment, the second slider  42  for operating the second operation wire  26  is placed in a distal end side thereof, and the first slider  41  for operating the first operation wire  15  is placed in a position adjacent to the second slider  42  (the positional relationship is opposite to that of the above-described embodiment). 
         [0114]    The foreign object capturing device  10   a  has a shape in which the distal end side of the second operation wire  26  is caused to have a predetermined curved shape as an initial shape (see  FIG. 15 ). Namely, as shown in  FIG. 17A , the second operation wire  25  is caused to have a curved shape as an initial shape, which expands in the outer circumference and circumferentially extends, as viewed from the axial distal end side, in a free state where the second operation wire  26  is not operated (a state where the second slider  42  is placed in a position closer to the base end of the handle). 
         [0115]    As shown in  FIGS. 15 and 17A , the curved shape of the second operation wire  26  in the embodiment has: a distal end portion  26   a  which is bent in the outer radial direction from the bundling member  22  that is a coupling portion between the plural framework wire members  20  and the second operation wire  26 ; a bent portion  26   b  which extends in the circumferential direction from the distal end portion  26   a  while expanding; and a curved portion  26   c  which extends from the bent portion  26   b  and returns toward the base end of the first operation wire  15  while being gently curved (see  FIG. 15 ) so as to pass outside a predetermined one of the framework wire members  20 . The shape of the second operation wire  26  is not limited to this mode. For example, the curved portion  26   c  may be caused to have a spiral shape with plural loops as an initial shape. However, it is preferable that the wire has at least the distal end portion  26   a  which is bent in the outer radial direction from the coupling portion, the bent portion  26   b  which extends in the circumferential direction while expanding, and the curved portion  26   c  which returns toward the base end of the first operation wire  15 . 
         [0116]    The foreign object capturing device  10   a  is configured so that the second operation wire  26  expands in the outer radial direction by moving the second operation wire  25  relative to the first operation wire  15  toward the distal end (see  FIGS. 16, 17B, 18A, 18B and 19A ), and the second operation wire  26  is moved to the distal end side with respect to the coupling portion (bundling member  22 ) between the distal ends of the plural framework wire members  20  and the distal end of the second operation wire  26  by further relatively moving the second operation wire  26  toward the distal end (see  FIG. 19B ). 
         [0117]    In the embodiment, the second operation wire  26  is moved in the following manner. That is, when, in a free state which is shown in  FIG. 14 , and in which the second operation wire  26  is not operated, the second operation wire  25  is moved toward the distal end with respect to the first operation wire  15 , the second operation wire  26  expands in the outer radial direction as shown in  FIG. 18A , and the curved portion  26   c  butts against the inner wall of the tubular organ V 2  to be curved. When the second operation wire  26  is further moved toward the distal end, the curved portion  26   c  of the second operation wire  26  butts against the inner wall of the tubular organ V 2  to be further curved as shown in  FIG. 18B , and spirally expands along the inner wall of the tubular organ V 2 . When the second operation wire  26  is further moved toward the distal end, the curved portion  26   c  is moved toward the distal end so that the loop interval of the curved portion  26   c  is narrowed as shown in  FIG. 19A . When the second operation wire  26  is further moved toward the distal end, the curved portion  26   c  of the second operation wire  26  is moved to the distal end side with respect to the bundling member  22  as shown in  FIG. 19B . 
         [0118]    For the sake of convenience,  FIGS. 18A, 18B and 19A  show a state where a stone K (see  FIG. 19B ) does not exist in the tubular organ V 2 . 
         [0119]    The second operation wire  26  in the embodiment is formed by a twisted wire which is configured by twisting plural wire members. Alternatively, the second operation wire may be formed by a solid wire which is configured by a single wire, and is not particularly limited. Because the foreign object G such as a relatively-large stone is captured by causing the second operation wire  26  to tangle with the outer circumference of the stone, however, the wire is preferably formed by a twisted wire which is flexible and easily bendable, and which has stiffness of a certain degree in order to transmit the operation force. 
         [0120]    The second operation wire  26  in the embodiment is formed by a single twisted wire which is configured by twisting plural wire members. Alternatively, the second operation wire may be formed by plural wires as shown in  FIGS. 21A to 22B . 
         [0121]    In the structure shown in  FIGS. 21A and 21B , a pair of second operation wires  26 ,  26  are disposed which are caused to have a curved shape as an initial shape, such that they are point-symmetric about the axis C (center of the bundling member  22 ) of the first operation wire  15  as viewed from the axial distal end side in a free state. As shown in  FIG. 21A , the pair of second operation wires  26 ,  26  form a substantially 8-like shape, and, in the case where the second operation wires  26  are moved toward the distal end, the curved portion  26   c  of each of the second operation wires  26  expands in the outer radial direction, and the whole pair of second operation wires  26  are deformed so as to exhibit a circular shape as shown in  FIG. 21B . 
         [0122]    In the structure shown in  FIGS. 22A and 22B , a pair of second operation wires  26 ,  26  are disposed, and are caused to have a curved shape as an initial shape, such that they are axisymmetric about a line L that passes through the axis C (center of the bundling member  22 ) of the first operation wire  15  as viewed from the axial distal end side in a free state, and that extends along the diameter expansion direction of the framework wire member  20  which is placed in the middle of the plural framework wire members  20 . As shown in  FIG. 22A , the pair of second operation wires  26 ,  26  form a shape similar to a bow knot, and, in the case where the second operation wires  26  are moved toward the distal end, the curved portion  26   c  of each of the second operation wires  26  expands in the outer radial direction, and the whole pair of second operation wires  26 ,  26  are deformed so as to exhibit a heart shape as shown in  FIG. 22B . 
         [0123]    Similarly with the second operation wire  25  in the above-described embodiment, the second operation wire  26  may be formed by, for example, stainless steel, Ta, Ti, Pt, Au, W, or a shape memory alloy such as a Ni—Ti based alloy, a Co—Cr based alloy, a Co—Cr—Ni based alloy, a Cu—Zn—X (X=Al, Fe, etc.) based alloy, or a Ni—Ti—X (X=Fe, Cu, V, Co, etc.) based alloy. Among them, a shape memory alloy is preferably used so that the second operation wire  26  is caused to have a predetermined curved shape as an initial shape. In the case where the second operation wire  26  is formed by a twisted wire, one or plural wire members in the twisted wire are preferably formed by a radiopaque metal, for example, Pt, Ti, Pd, Rh, Au, W, or an alloy thereof so that the second operation wire  26  is visible under radiation imaging. 
         [0124]    As shown in  FIG. 20 , the thus structured foreign object capturing device  10   a  may be preferably used in the case where, with respect to so-called stacked stones in which plural stones K are produced in a line along the path of the tubular organ V 2  such as the bile duct, the stones K are to be sequentially captured from the proximal side of the tubular organ V 2 . 
         [0125]    This will be described with reference also to  FIG. 20  and photographs ( FIGS. 23 to 29 ) of an example (described later) of the foreign object capturing device  10   a  having the above-described structure. In  FIGS. 23 to 29 , a tube (in the following description, described as “tubular organ”) modeled after a tubular organ is disposed as a body cavity, and plural stones (in the following description, described as “stones”) modeled after stones are placed in the tube. 
         [0126]    In a state where the plural framework wire members  20  and the second operation wire  26  are accommodated in the distal end portion of the catheter  45 , firstly, the distal end portion of the catheter  45  is moved to the front side of the most front stone K in the stacked stones produced in the tubular organ V 2 , through the endoscope  5  and the guide wire  1 . 
         [0127]    In this state, after the plural framework wire members  20  and the second operation wire  26  are projected from the distal end opening of the catheter  45  (see  FIG. 14 ), the bundling member  22  in the distal end is inserted between the stone K and the inner wall of the tubular organ V 2  as shown in  FIG. 23 , and positioning of the bundling member  22  is performed. 
         [0128]    When the second slider  42  is thereafter slid toward the distal end while holding the first slider  41 , the second operation wire  26  expands in the outer radial direction, and the curved portion  26   c  butts against the inner wall of the tubular organ V 2  to be curved (see  FIG. 18A ). When the second slider  42  is further slid toward the distal end, the curved portion  26   c  of the second operation wire  26  butts against the inner wall of the tubular organ V 2  to be further curved, and spirally expands (see  FIG. 18B ) and enters between the stone K and the inner wall of the tubular organ V 2  to start an operation of enclosing the stone K (see  FIG. 24 ). At this time, the stone K is supported by the plural framework wire members  20 , and therefore, the stone K is hardly positionally shifted. 
         [0129]    When the second slider  42  is further slid toward the distal end, the curved portion  26   c  of the second operation wire  26  is moved toward the distal end so that the loop interval is narrowed (see  FIG. 19A ), and the stone K is further enclosed (see  FIG. 25 ). When the second slider  42  is further slid toward the distal end, the curved portion  26   c  of the second operation wire  26  is moved to the distal end side with respect to the bundling member  22 , and, as shown in  FIGS. 19B, 20, and 26 , can enclose and capture the stone K so as to tangle with the stone, and the stone can be taken out in a manner that it is scraped off from the inner wall of the tubular organ V 2  (see  FIG. 27 ). 
         [0130]    The stone K can be discharged into the tubular organ V 1  by, in the above-described state, pulling the whole foreign object capturing device  10   a  toward the proximal side, moving the plural framework wire members  20  and the second operation wire  26  to the large-diameter tubular organ V 1  such as the duodenum, and adequately sliding the first slider  41  and second slider  42  of the operation handle  40 . Thereafter, the stones K in the tubular organ V 2  can be captured and discharged by repeating the work plural times. 
         [0131]    According to the foreign object capturing device  10   a  in the embodiment, as described above, the second operation wire  26  is caused to have a curved shape as a free-state initial shape as viewed from the axial distal end side. When the second operation wire  25  is moved relative to the first operation wire  15  toward the distal end, therefore, the curved portion expands along the inner wall of a body cavity, enters between a foreign object and the inner wall of the body cavity, and encloses and captures the foreign object, and the foreign object can be taken out in a manner that it is scraped off from the inner wall of the body cavity. 
         [0132]    Furthermore, the embodiment is configured so that the second operation wire  26  expands in the outer radial direction by moving the second operation wire  26  relative to the first operation wire  15  toward the distal end, and moves to the distal end side with respect to the coupling portion (bundling member  22 ) between the distal ends of the plural framework wire members  20  and the distal end of the second operation wire  26  by further relatively moving the second operation wire  26  toward the distal end. 
         [0133]    In the case where plural large foreign objects lie in a line along the path in a body cavity as shown in  FIG. 20 , the foreign objects get stuck unless the foreign objects are sequentially taken out beginning with the front foreign object. In such case, according to the foreign object capturing device  10   a  of the embodiment, the second operation wire  26  expands in the outer radial direction and moves to the distal end side with respect to the coupling portion (bundling member  22 ) between the distal ends of the plural framework wire members  20  and the distal end of the second operation wire  26  by placing the distal end portion of the foreign object capturing device  10   a  in front of the most front foreign object, and moving the second operation wire  26  relative to the first operation wire  15  toward the distal end. Therefore, the second operation wire  26  can tangle with and capture the front foreign object, and the foreign objects can be sequentially taken out beginning with the front foreign object. 
       Example 
     Production of Foreign Object Capturing Device 
       [0134]    A foreign object capturing device having a structure similar to the foreign object capturing device  10   a  of the embodiment shown in  FIGS. 14 to 20  is produced. 
         [0135]    The first operation wire  15  is made of stainless steel, also the plural framework wire members  20  are made of stainless steel, and the second operation wire  26  is formed by a single twisted wire which is configured by twisting  8  wire members made of stainless steel. 
         [0136]    (Test for Checking Capture Performance) 
         [0137]    Plural foreign objects (stones) are placed in a resin tube, and an operation test of capturing the foreign objects is performed using the above-described foreign object capturing device. As described above, as shown in  FIGS. 23 to 26 , the foreign objects are safely captured by the second operation wire  26 , and are taken out as shown in  FIG. 27 . It is also confirmed that, as shown in  FIGS. 28 and 29 , the second operation wire  26  can enclose a foreign object so as to tangle with the outer circumference of the foreign object, and capture the foreign object. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           10 ,  10   a  body-cavity foreign object capturing device (foreign object capturing device) 
           15  first operation wire 
           20  framework wire member 
           25 ,  26  second operation wire 
           30  basket 
           35  resin membrane 
           40  operation handle 
           45  catheter