Abstract:
A biopsy instrument including: a needle pipe formed in a tubular shape having a convex section, the convex section having an end section, the convex section being provided at a distal end section of the needle pipe; a distal end tip provided so as to be capable of moving longitudinally with respect to the needle pipe; a manipulation member connected to the distal end tip, the manipulation member being disposed in the needle pipe; and a circumferential edge provided at each of a proximal end side of the distal end tip and a distal end side of the needle pipe; wherein an interior of the distal end tip and an interior of the needle pipe define a cavity to capture a target tissue when the distal end tip is retracted towards the needle pipe.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation application based on a PCT International Application No. PCT/JP2013/076243, filed on Sep. 27, 2013, whose priority is claimed on U.S. Provisional Patent Application No. 61/710,210, filed on Oct. 5, 2012. The contents of both the PCT International Application and the U.S. Provisional Patent Application are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present disclosure relates generally to a biopsy instrument configured to collect a body tissue, and more particularly, to a biopsy instrument inserted into a treatment tool channel of an endoscope and used therein. 
         [0004]    2. Description of Related Art 
         [0005]    In the related art, an inspection method known as a biopsy, in which a small amount of body tissue is collected and the body tissue is observed using a microscope, is known. As a biopsy instrument configured to endoscopically collect the body tissue used for a biopsy, for example, Japanese Patent Application, First Publication No. S61-279236 discloses a biopsy instrument. The biopsy instrument includes a distal end tip, a manipulation wire connected to the distal end tip, and a flexible tube having a distal end member formed at a distal end thereof and through which the manipulation wire is inserted. A hole having an open surface is formed at a proximal end side of the distal end tip, and a sharp cutting blade is formed throughout the entire circumferential edge of the hole. When the distal end tip is inserted into the tissue and then is used to pull the manipulation wire to retract the distal end tip, a portion of the tissue is sandwiched between the cutting blade and the distal end member to be cut and accommodated in a tissue piece collecting hole. Accordingly, the biopsy instrument is capable of collecting the body tissue. 
       SUMMARY OF THE INVENTION 
       [0006]    A biopsy instrument is provided, which includes a needle pipe formed in a tubular shape having a convex section with a sharp end section provided at a distal end section of the needle pipe, a distal end tip provided so as to be capable of advancing and retracting with respect to the needle pipe, a manipulation member connected to the distal end tip and inserted into the needle pipe, and a cutting blade section provided at a proximal end side of the distal end tip and having a sharp end section. 
         [0007]    A plurality of the cutting blade sections may be provided at the proximal end side of the distal end tip, the needle pipe may have a plurality of the convex sections, and a number of the cutting blade sections may be the same as a number of the convex sections. 
         [0008]    The end section of the cutting blade section may be disposed between the plurality of the convex sections in a circumferential direction of the needle pipe. The plurality of the convex sections and the plurality of the cutting blade sections may be alternately disposed in the circumferential direction. 
         [0009]    The distal end tip may have a sharp puncturing section formed at a distal end side of the distal end tip. 
         [0010]    The width of a distal end side of the needle pipe may be set such that the distal end side of the needle pipe is capable of entering the distal end tip. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a view showing the overall configuration of a biopsy instrument according to a first embodiment of the present invention; 
           [0012]      FIG. 2A  is an enlarged view showing a periphery of a distal end section of a needle pipe of the biopsy instrument according to the first embodiment of the present invention; 
           [0013]      FIG. 2B  is a view when seen in a direction of an arrow A of  FIG. 2A ; 
           [0014]      FIG. 3  is a cross-sectional view of the distal end section of the biopsy instrument according to the first embodiment of the present invention; 
           [0015]      FIG. 4  is a view showing a process upon use of the biopsy instrument according to the first embodiment of the present invention; 
           [0016]      FIG. 5  is a view showing a process upon use of the biopsy instrument according to the first embodiment of the present invention; 
           [0017]      FIG. 6  is a view showing a process upon use of the biopsy instrument according to the first embodiment of the present invention; and 
           [0018]      FIG. 7  is an enlarged view showing a periphery of a distal end section of a needle pipe of a biopsy instrument according to a second embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     First Embodiment 
       [0019]    Hereinafter, a first embodiment of a biopsy instrument will be described with reference to  FIGS. 1 to 6 . 
         [0020]      FIG. 1  is a view showing an overall configuration of a biopsy instrument  1  of the first embodiment. The biopsy instrument  1  includes a long needle pipe  10  having flexibility, a distal end tip  20 , a sheath  40 , and a manipulation section (a manipulation member)  50 . The distal end tip  20  is inserted so as to be capable of advancing and retracting with respect to the needle pipe  10 . The needle pipe  10  is inserted into the sheath  40  so as to capable of advancing and retracting. The manipulation section  50  is attached to a proximal end section of the needle pipe  10 . 
         [0021]      FIG. 2A  is an enlarged view showing a periphery of the distal end section of the needle pipe  10 .  FIG. 2B  is a view when seen in a direction of an arrow A shown in FIG.  2 A. The needle pipe  10  is formed of a metal such as stainless steel or the like in a tubular shape having a lumen. The needle pipe  10  has a small outer diameter of, for example, about 1 to 2 millimeters (mm) and also has flexibility. As shown in  FIGS. 2A and 2B , the needle pipe  10  has two convex sections  11  having sharp end sections  11   a  disposed at the distal end of the needle pipe  10 . The two convex sections  11  are formed by cutting a portion of the member that forms the needle pipe  10  such that distal end surfaces of the needle pipe  10  are inclined with respect to an axis X1 of the needle pipe  10 , and have inclined surfaces  10   a  and  10   b  which approach an outer circumferential surface of the needle pipe  10  as it goes toward the proximal end of the needle pipe  10 . 
         [0022]      FIG. 3  is a cross-sectional view of the distal end section of the biopsy instrument  1 . The distal end tip  20  has a sharp puncturing section  21  with a substantially conical shape and being disposed at the distal end side of the distal end tip  20 . The proximal end side of the distal end tip  20  is formed in a substantially cylindrical shape having a lumen. Since an outer diameter of the distal end tip  20  is smaller than the inner diameter of the needle pipe  10 , as shown in  FIG. 3 , the distal end tip  20  is capable of entering the needle pipe  10 . 
         [0023]    Inclined surfaces  20   a  and ((not shown but substantially similar to inclined surface  20   a  and offset by 180 degrees from inclined surface  20   a ) are formed at the proximal end side of the distal end tip  20  through the same processing as the distal end section of the needle pipe  10 . Two cutting blade sections  22  having sharp end sections are formed at end sections of the inclined surfaces  20   a  and  20   b.  A manipulation wire (a manipulation member)  30  is connected to the distal end tip  20  in the lumen by welding or the like. The manipulation wire  30  extends to the manipulation section  50  through the inside of the needle pipe  10  and is configured to be capable of advancing and retracting with respect to the needle pipe  10 . 
         [0024]    Positions of the distal end tip  20  and the needle pipe  10  are determined in a way that the convex section  11  and the cutting blade section  22  are disposed to be alternately positioned in a circumferential direction of the needle pipe  10 . In the first embodiment, the two convex sections  11  are disposed at positions separated from each other by 180 degrees in the circumferential direction of the needle pipe  10 . The two cutting blade sections  22  are disposed at positions separated from each other by 180 degrees in the circumferential direction of the distal end tip  20 . A position relationship between the distal end tip  20  and the needle pipe  10  is defined such that each of the cutting blade sections  22  is disposed at a position separated from each of the convex sections  11  in the circumferential direction of the needle pipe  10  by 90 degrees. 
         [0025]    The sheath  40  may be appropriately selected from known sheaths having flexibility and through which the needle pipe  10  is capable of being inserted to advance and retract. The material of the sheath  40  is not particularly limited either and various known materials such as a resin, a coil, or the like, may be used. 
         [0026]    As shown in  FIG. 1 , the manipulation section  50  includes a manipulation section main body  51  and a slider  52 . The manipulation section main body  51  is fixed to the proximal end section of the needle pipe  10 . The slider  52  is attached to be slidable in a longitudinal direction of the manipulation section main body  51 . A basic configuration of the manipulation section  50  is known. The proximal end section of the manipulation wire  30  extending through the inside of the needle pipe  10  protrudes into the internal space of the manipulation section main body  51  to be fixed to the slider  52 . Accordingly, as the slider  52  is slid with respect to the manipulation section main body  51 , the manipulation wire  30  is capable of advancing and retracting with respect to the needle pipe  10 . When the manipulation section main body  51  is relatively moved with respect to the sheath  40 , the needle pipe  10  and the distal end tip  20  is capable of advancing and retracting with respect to the sheath  40 . Accordingly, the manipulation section  50  is capable of adjusting the protrusion amount of the needle pipe  10  and the distal end tip  20  protruding from the distal end of the sheath  40 . 
         [0027]    In an operation using the biopsy instrument  1  of the first embodiment having the above-mentioned configuration, the example in which the pancreas is a tissue of a biopsy target (hereinafter, simply referred to as a “target tissue”) will be described. 
         [0028]    An operator first introduces an endoscope (not shown) into a patient&#39;s body and moves a distal end section of the endoscope to the vicinity of the pancreas. Next, in a state in which the needle pipe  10  and the distal end tip  20  are accommodated in the sheath  40 , the operator inserts the biopsy instrument  1  into a forceps channel of the endoscope from the puncturing section  21  side, and causes the distal end section of the sheath  40  to protrude from the distal end of the forceps channel. The endoscope may be appropriately selected from various known endoscopes such as an optical endoscope, an ultrasonic endoscope, and so on, according to the kind or the position of the target tissue. 
         [0029]    The operator manipulates the manipulation section main body  51  while checking the pancreas and a portion of the pancreas from which the tissue piece is collected (a collecting area) within a field of vision of the endoscope, and causes the needle pipe  10  and the distal end tip  20  to be protruded from the sheath  40 . Further, as shown in  FIG. 4 , the operator performs manipulation of inserting the puncturing section  21  into the pancreas Pc and advancing the puncturing section  21  to a position slightly in front of the collecting area by, for example, several millimeters. 
         [0030]    Next, when the operator moves the slider  52  forward with respect to the manipulation section main body  51 , the manipulation wire  30  connected to the slider  52  moves forward with respect to the needle pipe  10 . As a result, as shown in  FIG. 5 , the distal end tip  20  protrudes in front of the needle pipe  10 . Accordingly, the distal end tip  20  is separated from the needle pipe  10 , and a portion of the tissue of the pancreas Pc enters a space generated between the distal end tip  20  and the needle pipe  10 . 
         [0031]    When the operator retracts the slider  52  with respect to the manipulation section main body  51  in this state, as shown in  FIG. 6 , the distal end tip  20  is retracted to approach the needle pipe  10 . Here, the cutting blade section  22  of the retracted distal end tip  20  presses and gradually cuts the tissue entering between the distal end tip  20  and the needle pipe  10 . A collecting area of the entered tissue disposed between the two cutting blade sections  22  in the circumferential direction of the distal end tip  20  is hard for the distal end tip  20  to cut. However, when the distal end tip  20  approaches the needle pipe  10 , the convex section  11  of the needle pipe  10  presses the collecting area such that the collecting area is sandwiched between the convex section  11  and the distal end tip  20 . As a result, the collecting area is gradually cut by the convex section  11  of the needle pipe  10  disposed at an opposite side of the distal end tip  20 . When the distal end tip  20  is retracted until the inclined surface  20   a  formed at the proximal end side of the distal end tip  20  and the other inclined surface  20   b  (not shown) are disposed in the lumen of the needle pipe  10 , and the portion of the tissue is cut, separated and accommodated in the needle pipe  10  as a tissue piece. 
         [0032]    According to the biopsy instrument  1  of the first embodiment, the two convex sections  11  having the sharp distal ends are disposed at the needle pipe  10 , and the two the cutting blade sections  22  having the sharp distal ends are also disposed at the distal end tip  20 . For this reason, when the distal end tip  20  approaches the needle pipe  10  to gradually cut the tissue, a force applied to the tissue is capable of being concentrated on the convex section  11  and the cutting blade section  22  to appropriately cut the tissue. As a result, the body tissue is capable of being securely cut and collected with easy manipulation through retraction of the slider  52 . 
         [0033]    In addition, according to the biopsy instrument  1  of the first embodiment, the convex sections  11  and the cutting blade sections  22  are alternately disposed in the circumferential direction of the needle pipe  10 . For this reason, an area of the tissue that is hard for the convex section  11  to cut is cut by the cutting blade section  22 , and an area of the tissue that is hard for the cutting blade section  22  to cut is cut by the convex section  11 . As a result, separation and collection of the body tissue is capable of being more appropriately performed. 
         [0034]    In the flow of the above-mentioned procedure, an example in which the distal end tip is moved forward with respect to the needle pipe by advancing the puncturing section to a position slightly in front of the collecting area has been described. However, instead of this, a procedure of advancing the puncturing section to the collecting area or a position slightly behind the collecting area and then retracting the needle pipe with respect to the distal end tip may be used. The distal end tip is capable of being separated from the needle pipe in this manipulation as well. As a result, as the distal end tip approaches the needle pipe, cutting and collecting of the tissue is capable of being performed in the same manner. 
       Second Embodiment 
       [0035]    Next, a second embodiment will be described with reference to  FIG. 7 . A biopsy instrument  61  according to the second embodiment is distinguished from the above-mentioned biopsy instrument  1  in that a size relation between the distal end tip and the needle pipe is varied. Further, in the following description, the same elements as the above-mentioned second embodiment are designated by the same reference numerals and an overlapping description thereof will be omitted here. 
         [0036]      FIG. 7  is an enlarged view of a periphery of a distal end section of a needle pipe  63  in the biopsy instrument  61  according to the second embodiment. In the biopsy instrument  61 , as shown in  FIG. 7 , the inner diameter of a distal end tip  62  near a proximal end is set to be larger than the outer diameter of the needle pipe  63 . In the biopsy instrument  61 , the width of a distal end side of the needle pipe  63  including a convex section  64  is set such that the distal end side of the needle pipe is capable of entering the proximal end side of the distal end tip  62 . The other aspects are substantially the same as those of the biopsy instrument  1  according to the first embodiment. 
         [0037]    In the biopsy instrument  61  according to the present second embodiment, similar to that of the first embodiment, the distal end tip  62  is capable of approaching the needle pipe  63  through easy manipulation by simply extracting the slider  52  to securely cut and collect the body tissue. 
         [0038]    In addition, when the needle pipe  63  collides with the distal end tip  62 , the distal end tip  62  is disposed not to retract further with respect to the needle pipe  63 . For this reason, even if a reaction force is applied to the distal end tip  62  from the tissue when the puncturing section  21  is inserted into the target tissue, the puncturing section  21  does not enter the needle pipe  63 . Accordingly, there is no need to hold the slider  52  such that the puncturing section  21  does not enter the needle pipe  63  upon insertion of the target tissue, and the manipulation is capable of being further facilitated. 
         [0039]    Hereinabove, while the above embodiments have been described, the technical spirit of the present invention is not limited to the embodiments, and combinations of the components may be varied or various modifications may be added to or deleted from the components in the embodiments without departing from the spirit of the present invention. 
         [0040]    For example, the number of convex sections may be equal to the number of cutting blade sections. For example, neither of the number of convex sections or the number of cutting blade sections is limited to 2 as described in the above-mentioned embodiment, and each of the number of convex sections and the number of cutting blade sections may be 3 or more. However, as the number of convex sections and the number of cutting blade sections are increased, a force applied to the tissue is distributed. For this reason, the skill required to manipulate the distal end tip to approach the needle pipe is increased. Accordingly, both the number of convex sections and the number of cutting blade sections is most preferably 2. 
         [0041]    Further, a certain effect is capable of being obtained even when only one of each of the convex section and the cutting blade section is provided or the number of convex sections is different from the number of cutting blade sections. 
         [0042]    While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit and scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.