JP2011147551A - Catheter and catheter insertion instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catheter and a catheter insertion instrument, capable of making the distal end of the catheter reach a medication target part while evading the important tissue of a blood vessel, a pancreatic duct and a lymph vessel, etc. <P>SOLUTION: The catheter 1 includes: a thin and long tubular body 3 having a lumen in the inside; a first puncture needle 2 directly or indirectly attached to the body 3 so as to be slid in the axial direction of the body 3, and separable from the body 3 by being slid from the position of projecting the distal end from the distal end of the body 3 to the proximal end of the body 3; and a second puncture needle 4 directly or indirectly attached to the body 3 so as to be slid in the axial direction of the body 3, having at least one of sharpness and rigidity different from that of the first puncture needle 3, and separable from the body 3 by being slid from the position of projecting the distal end from the distal end of the body 3 to the proximal end of the body 3. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a catheter accommodated in a catheter that is punctured into a living tissue of a mammal including a human being, and a catheter insertion device.

  Conventionally, for the purpose of medication, a tubular catheter has been inserted into the living tissue of mammals including humans, and fluids such as drugs have been discharged from the through holes at the distal end of the catheter. As such a catheter, an indwelling catheter comprising a tube-shaped catheter body and a bent elastic wire inserted at one end inside the catheter, and mainly administering a drug solution such as an anticancer drug into the blood vessel in the vicinity of the tumor Has been proposed (see, for example, Patent Document 1). By using this catheter to administer an anticancer agent to blood vessels in the vicinity of the tumor, damage to normal cells is reduced, and an anticancer effect is achieved with a small amount of drug.

Japanese Patent No. 3274384

  However, in the method described in Patent Document 1, a drug is injected into the blood vessel, and the drug cannot contact the tumor cells until the drug in the blood leaks out of the blood vessel. There was a problem that many were not taken up by the tumor, but circulated in the body through the bloodstream and excreted.

  For this reason, in recent years, in order to increase the amount of the drug in contact with tumor cells and further improve the drug efficacy, it is required to inject the drug directly into the tissue in the vicinity of the tumor. According to this method of directly injecting a drug into a tissue, the dose of the drug can be reduced as compared with the method of injecting the drug into the blood vessel, so that a reduction in side effects can be expected.

  Here, in the method of directly injecting the drug into the tissue, when the catheter is punctured into the living tissue, avoid the important tissue such as blood vessels, pancreatic ducts, lymphatic vessels, etc. in the tissue and the body surface as much as possible, and the tip of the catheter is affected There is a strong demand to reach the medication purpose part.

  The present invention has been made in view of the above, and provides a catheter and a catheter insertion device that can reach the distal end of the catheter to the administration target portion while avoiding important tissues such as blood vessels, pancreatic ducts, and lymphatic vessels. With the goal.

  In order to solve the above-described problems and achieve the object, a catheter according to the present invention is a catheter that is pierced into a living tissue of a mammal including a human, and has an elongated tubular casing having a lumen therein, First or indirectly attached to the housing so as to be slidable in the axial direction of the housing, the tip is slid toward the base end of the housing from a position protruding from the tip of the housing, and is separable from the housing. The puncture needle is attached directly or indirectly to the housing so as to be slidable in the axial direction of the housing, and differs from the first puncture needle in at least one of sharpness and rigidity, and the tip protrudes from the tip of the housing. And a second puncture needle that is slidable from a position toward the base end of the housing and is separable from the housing.

  In the catheter according to the present invention, in the above invention, the first puncture needle and the second puncture needle have a tubular shape with a sharp tip, and the casing, the first puncture needle, and the Each central axis of the second puncture needle is arranged substantially coaxially.

  In the catheter according to the present invention, the length of the first puncture needle tip protruding from the case tip when the first puncture needle slides most distally relative to the case in the above invention The protrusion length of the tip of the second puncture needle from the tip of the case when the second puncture needle slides in the most distal direction with respect to the case is different.

  In the catheter according to the present invention, in the above invention, the casing is at least partially accommodated in the lumen of the first puncture needle, and the second puncture needle is at least in the lumen of the casing. Part of it is housed.

  In the catheter according to the present invention, in the above invention, at least a part of the first puncture needle is accommodated in the lumen of the housing, and the second puncture needle is the first puncture needle. It is characterized in that at least a part is accommodated in the lumen.

  In the catheter according to the present invention as set forth in the invention described above, at least a part of the second puncture needle is accommodated in a lumen of the first puncture needle, and the casing is formed of the second puncture needle. It is characterized in that at least a part is accommodated in the lumen.

  Further, in the catheter according to the present invention, in the above invention, at least one of the first puncture needle and the second puncture needle has a bent portion that is bent when a predetermined amount of force is applied in the axial direction. Features.

  Further, the catheter according to the present invention has a locking portion for locking the relative movement in the axial direction of the first puncture needle and the second puncture needle in the above invention, The locking is released when a force of a predetermined amount or more that separates the tip of the first puncture needle and the tip of the second puncture needle in the axial direction is applied.

  In the above invention, the catheter according to the present invention further includes a connection mechanism that connects the first puncture needle and the second puncture needle to each other, and the connection mechanism includes the first puncture needle. A first state in which the first puncture needle and the second puncture needle are coupled so that a distal end position is closer to the distal end side than the distal end position of the second puncture needle; A transition is made between a second state in which the first puncture needle and the second puncture needle are connected so that a distal end position is closer to the distal end side than the distal end position of the first puncture needle. And

  In the catheter according to the present invention, in the above invention, the second puncture needle has a tubular shape with a pointed tip and a closed end opening, and the second puncture needle is formed at the closed end portion. The first puncture needle has a tip sharpness different from the second puncture needle, and has a distal end member that fits into the slit and a proximal end side. And a linear member connected to the tip member, wherein the second puncture needle is at least partially accommodated in the lumen of the housing, and the first puncture needle is the second puncture needle The tip member protrudes from the slit in a state where at least a part is accommodated in the lumen of the puncture needle.

  In the catheter according to the present invention, in the above invention, the closed tip portion of the second puncture needle is formed by an outer surface member and an elastic member, and nothing is inserted into the slit. In the absence, the elastic member is blocked.

  The catheter insertion device according to the present invention is a catheter insertion device used in the above invention for inserting a catheter having an elongated tubular housing having a lumen therein into a living tissue of a mammal including a human. In addition, it is directly or indirectly attached to the casing so as to be slidable in the axial direction of the casing, and can be separated from the casing by sliding toward the base end of the casing from a position where the tip protrudes from the tip of the casing. The first puncture needle is directly or indirectly attached to the casing so as to be slidable in the axial direction of the casing. The first puncture needle is different from the first puncture needle in at least one of sharpness and rigidity, and the distal end extends from the distal end of the casing. And a second puncture needle that is slidable from the protruding position toward the base end of the housing and can be separated from the housing.

  According to the present invention, the elongate tubular casing having a lumen therein is attached to the casing directly or indirectly so as to be slidable in the axial direction, and the distal end slides from the position protruding from the distal end of the casing toward the proximal end of the casing. A first puncture needle that is separable from the housing, and is directly or indirectly attached to the housing so as to be slidable in the axial direction of the housing, and differs from the first puncture needle in at least one of sharpness and rigidity, and the tip is the housing. And a first puncture needle that can be separated from the housing by sliding toward the proximal end of the housing from the position protruding from the tip of the body, and by switching the puncture needle according to the puncture target, blood vessels, pancreatic ducts, lymphatic vessels, etc. It is possible to smoothly reach the distal end of the catheter to the administration target portion while avoiding important tissue.

FIG. 1 is an exploded perspective view of the catheter according to the first embodiment. FIG. 2 is a cross-sectional view of the catheter assembled with each member shown in FIG. 1 cut along the central axis. FIG. 3 is a diagram illustrating a method of using the catheter shown in FIG. FIG. 4 is a cross-sectional view of another catheter according to the first embodiment cut along a central axis. FIG. 5 is a cross-sectional view of another catheter according to the first embodiment cut along the central axis. FIG. 6 is a cross-sectional view of another catheter according to the first embodiment cut along a central axis. FIG. 7 is a cross-sectional view of another catheter according to the first embodiment cut along a central axis. FIG. 8 is a cross-sectional view of another catheter according to the first embodiment cut along the central axis. FIG. 9 is a cross-sectional view of the catheter according to the second embodiment cut along the axial direction. FIG. 10 is a cross-sectional view of another catheter according to the second embodiment cut along a central axis. FIG. 11 is a cross-sectional view of the catheter according to the third embodiment cut along the axial direction. FIG. 12 is a cross-sectional view of another catheter according to the third embodiment cut along a central axis. FIG. 13 is an exploded perspective view of the first puncture needle and the second puncture needle shown in FIG. FIG. 14 is a perspective view of the catheter 301a in each state shown in FIGS. 12 (1) and 12 (2). FIG. 15 is a cross-sectional view taken along line AA in FIG. FIG. 16 is a cross-sectional view of another catheter according to the first to third embodiments cut along the axial direction. FIG. 17 is an exploded perspective view of the catheter according to the fourth embodiment. 18 is a left side view of the second puncture needle shown in FIG. FIG. 19 is a perspective view of a catheter according to the fourth embodiment. 20 is a cross-sectional view in the axial direction of the tip of the second puncture needle 504 shown in FIG. FIG. 21 is a perspective view of another catheter tip according to the fourth embodiment. 22 is a left side view of another example of the second puncture needle shown in FIG.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a catheter and a catheter insertion device that are punctured into a living tissue of a mammal including a human and administer a drug will be described as embodiments for carrying out the present invention with reference to the drawings. Note that the present invention is not limited to the embodiments. In the description of the drawings, the same parts are denoted by the same reference numerals.

(Embodiment 1)
FIG. 1 is an exploded perspective view of the catheter according to the first embodiment. FIG. 2 is a cross-sectional view of the catheter assembled with each member shown in FIG. 1 cut along the central axis. As shown in FIGS. 1 and 2, the catheter 1 according to the first embodiment includes an elongated tubular casing 3 having a lumen therein, a first puncture needle 2, and a second puncture needle 4. .

  The housing 3 is provided with an opening communicating with the internal lumen at the distal end and an opening at the proximal end so that a medicine or the like can be input from the opening. The casing 3 is made of a biocompatible flexible material (for example, polyurethane, elastic silicon, fluororesin, polyvinyl chloride, polyethylene, natural rubber).

  The first puncture needle 2 and the second puncture needle 4 have a tubular shape with a sharp tip. The first puncture needle 2 and the second puncture needle 4 are formed so as to have different sharpness. In the example shown in FIGS. 1 and 2, the first puncture needle 2 has a sharper tip than the second puncture needle 4. As the material of the puncture needles 2 and 4, for example, metal (stainless steel, titanium, aluminum, etc.), resin (fluororesin or various engineering plastics), or the like can be used.

  When the first puncture needle 2 and the second puncture needle 4 are assembled to the housing 3, the central axes of the housing 3, the first puncture needle 2, and the second puncture needle 4 are substantially coaxial. It is arranged like this. The housing 3 is at least partially housed in the lumen of the first puncture needle 2, and the second puncture needle 4 is at least partially housed in the lumen of the housing 3. Therefore, the 1st puncture needle 2 which accommodated the housing 3 in the lumen turns into the outer needle located in the outermost side, and the 2nd puncture needle 4 accommodated in the lumen of the housing 3 becomes the inner needle located in the innermost side. Become.

  As shown in FIG. 2, the first puncture needle 2 includes a pointed distal end portion 21, a cylindrical intermediate portion 22, a cylindrical proximal end portion 23 having an outer diameter larger than that of the intermediate portion, and a first stopper. 24. The first puncture needle 2 is attached to the housing 3 such that at least a part of the inner wall of the first puncture needle 2 contacts the outer surface of the housing 3. Specifically, the catheter housing 3 is accommodated in the lumen of the first puncture needle 2, and the housing 3 and the first puncture needle 2 are contained in the lumen corresponding to the intermediate portion 22 of the first puncture needle 2. The inner wall of the lumen is slidably in contact. The first puncture needle 2 is attached to the housing 3 so as to be slidable in the axial direction of the housing 3, and slides toward the base end of the housing 3 from the position where the distal end protrudes from the distal end of the housing 3. Separable. Furthermore, a gap 26 is formed in the lumen of the first puncture needle 2 so that the inner wall of the lumen of the first puncture needle 2 does not contact the outer surface of the housing 3. By providing this gap 26 and reducing the contact surface between the lumen inner wall of the second puncture needle 4 and the housing 3, the second puncture needle 4 can be smoothly slid from the outer surface of the housing 3.

  The second puncture needle 4 has a pointed distal end portion 41, a cylindrical intermediate portion 42, and a proximal end portion 43 having an outer diameter larger than that of the intermediate portion 42. In the second puncture needle 4, a protruding portion 44 having the same diameter as the proximal end portion 43 is formed between the distal end portion 41 and the intermediate portion 42. The second puncture needle 4 further includes a second stopper 45 at the proximal end portion 43. The second puncture needle 4 is attached in the housing 3 such that at least a part of the second puncture needle 4 contacts the inner wall of the housing 3. Specifically, at least a part of the second puncture needle 4 is accommodated in the lumen of the housing 3, and the second puncture needle 4 is disposed in front of the protruding portion 44 and the base end portion 43 in the lumen of the housing 3. The portion is slidably in contact with the inner wall of the lumen of the housing 3. Similarly to the first puncture needle 2, the second puncture needle 4 is attached to the housing 3 so as to be slidable in the axial direction of the housing 3, and the distal end protrudes from the distal end of the housing 3 toward the proximal end of the housing 3. And can be separated from the housing 3 by sliding. Further, in the lumen of the housing 3, a gap 46 is formed in which the second puncture needle 4 and the lumen inner wall of the housing 3 do not contact each other. By providing this gap 46 and reducing the contact surface between the lumen inner wall of the second puncture needle 4 and the housing 3, the second puncture needle 4 can be smoothly slid within the lumen of the housing 3.

  As shown in FIG. 2, the first puncture needle 2 and the second puncture needle 4 are positioned and assembled with respect to the housing 3 in a state where each slides most toward the distal end. In this assembled state, the relative positions of the first puncture needle 2 and the second puncture needle 4 are the first stopper 24 of the first puncture needle 2 and the second stopper 45 of the second puncture needle 4. Is determined by contact. The relative position between the second puncture needle 4 and the catheter housing 3 is determined by the second stopper 45 of the second puncture needle 4 coming into contact with the proximal end surface of the housing 3.

  By being positioned and assembled in this way, the tip of the first puncture needle 2 and the tip of the second puncture needle 4 are in different positions, and the tip of the first puncture needle 2 is the second one. It is located closer to the distal end side of the catheter 1 than the distal end of the puncture needle 4. In other words, when the first puncture needle 2 slides in the most distal direction with respect to the housing 3, the protruding length of the tip 21 from the distal end of the housing 3 and the second puncture needle 4 in the most distal direction with respect to the housing 3. The protruding length of the tip 41 from the tip of the housing 3 when sliding is different from each other. In this way, the first puncture needle 2 and the second puncture needle are arranged such that the distal end of the first puncture needle 2 is positioned closer to the distal end side of the catheter 1 than the distal end of the second puncture needle 4. A configuration in which 4 is assembled to the housing 3 is a basic configuration.

  In this catheter 1, the tip of the catheter 1 is smoothly punctured by switching the puncture needle protruding from the tip of the catheter 1 to one having an appropriate degree of sharpness according to the puncture target. A method of using the catheter 1 shown in FIG. 1 will be described. FIG. 3 is a view for explaining a method of using the catheter 1 shown in FIG. 1, and is a cross-sectional view of the catheter 1 shown in FIG. 1 cut along the axial direction.

  First, when puncturing the skin of the organ surface, it is desirable to use the first puncture needle 2 of the puncture needles 2 and 4 having a relatively high tip sharpness. This is because the organ surface has a film, and a certain amount of force is required to puncture the film. For this reason, the first puncture needle 2 having a high degree of tip sharpness is more suitable for puncturing by breaking the skin on the organ surface than the second puncture needle 4 having a low degree of tip sharpness.

  Therefore, when puncturing the surface of the organ surface, the distal end of the first puncture needle 2 is more distal than the distal end of the second puncture needle 4 as shown in FIG. The distal end of the catheter 1 is punctured to the surface of the organ 5 with the basic configuration located in FIG. In other words, the tip of the catheter 1 is punctured up to the surface of the organ 5 as indicated by the arrow Y1, with the tip of the first puncture needle 2 having a high degree of sharpness exposed at the tip of the catheter 1. In this case, the distal end of the catheter 1 is inserted until all the slopes of the distal end of the first puncture needle 2 are located under the skin of the organ 5 so that the distal end of the housing 3 is located under the skin of the organ 5.

  When the tip of the catheter 1 is punctured to the affected part 6, for example, a tumor, which is a drug administration target part inside the organ 5, the second puncture needle 4 having a relatively low tip sharpness among the puncture needles 2 and 4. Select. Since the inside of the organ 5 and the tumor are softer than the skin on the organ surface, the sharpness of the needle tip is not necessary as compared with the case of puncturing the skin on the organ surface. In addition, since there are many blood vessels such as blood vessels that perform important functions in the organ, there is a puncture needle whose tip is not so sharp from the viewpoint of protecting these vessels after puncturing the surface of the organ. desirable. A blood vessel such as a blood vessel is a tissue mainly containing smooth muscles, elastic fibers and collagen fibers, and has a relatively strong tissue having elasticity. On the other hand, other than the organ vasculature, it is a soft parenchyma. For this reason, even when the puncture needle is actually in contact with the vessel, the tip of the needle does not puncture the vessel when the tip is not so sharp, and the vessel avoids the puncture needle. The puncture needle can be deformed to avoid the vessel. Therefore, the second puncture needle 4 having a lower degree of sharpness than the first puncture needle 2 used for the membrane puncture of the organ 5 is desirable for puncture after the membrane of the organ 5 is once punctured.

  In order to switch the first puncture needle 2 exposed at the distal end of the catheter 1 to the second puncture needle 4, as shown by an arrow Y2 in FIG. The first puncture needle 2 is pulled out from the proximal end side of the catheter 1 by sliding from the distal end toward the proximal end. As a result, as shown in FIG. 3 (3), the distal end of the second puncture needle 4 with a low degree of sharpness is exposed at the distal end of the catheter 1. In this state, the catheter 1 is further inserted into the organ 5 as indicated by an arrow Y3. In this case, since the tip of the catheter 1 is the second puncture needle 4 with a low degree of sharpness, even if the tip of the second puncture needle 4 actually contacts the blood vessel B, the tip of the needle does not puncture the blood vessel B. The blood vessel B moves so as to avoid the puncture needle as indicated by an arrow Y4 in FIG. Then, as shown in FIG. 3 (4), the surface of the tumor 6 is punctured with the second puncture needle 4 and inserted until the tip of the housing 3 is located inside the tumor 6.

  Thereafter, as indicated by an arrow Y5 in FIG. 3 (5), the second puncture needle 4 is slid from the distal end of the housing 3 toward the proximal end, thereby causing the second puncture needle 4 from the proximal end side of the catheter 1 to move. As shown in FIG. 3 (6), the housing 3 is placed at a position where the distal end portion of the housing 3 is in the tumor 6. When the length of the housing 3 is insufficient, another tube may be connected to the base end side of the housing 3 and used. Further, the position of the catheter 1 can be confirmed by ultrasound, CT or the like during the operation. Then, by introducing a drug or the like from the opening at the proximal end of the catheter 1 as indicated by an arrow Y6, the drug is administered into the tumor 6 from the opening at the distal end of the catheter 1 as indicated by an arrow Y7.

  Thus, when puncturing the skin on the surface of the organ 5, the catheter 1 is held in the organ 5 with the basic configuration in which the tip of the first puncture needle 2 having a relatively high tip sharpness is exposed at the tip of the catheter 1. When puncturing to the surface and puncturing the inside of the organ 5 or the tumor 6, the first puncture needle 2 is pulled out, and the second puncture needle 4 having a relatively low tip sharpness is exposed at the distal end of the catheter 1. In this state, the tip of the catheter 1 can be reliably punctured on the organ surface, and the tip of the catheter can be smoothly reached to the administration target portion while avoiding important tissues such as blood vessels, pancreatic ducts and lymphatic vessels. .

  Since the second puncture needle located on the innermost side does not need to accommodate a member therein, as shown in the catheter 101 in FIG. 4, the second puncture needle 104 having the closed tip 141 is used as the inner needle. It can also be used. Although not shown, a solid structure puncture needle may be used as the second puncture needle.

(First Modification of Embodiment 1)
Next, a first modification of the first embodiment will be described. FIG. 5 is a cross-sectional view of the catheter according to the first modification of the first embodiment cut along the axial direction. As shown in FIGS. 5 (1) and 5 (2), in the catheter 1a according to the first modification, the proximal end portion 23a of the first puncture needle 2a is subjected to a predetermined amount of force in the axial direction. Bend. The catheter added when the tip of the catheter 1 is punctured into the body tissue as indicated by the arrow Y1a in FIG. 5 (1), and the tip of the first puncture needle 2a reaches the skin of the organ 5 as shown in FIG. 5 (2). The bendability of the base end portion 23a is set so that the base end portion 23a bends outward of the housing 3 as indicated by an arrow Y8 by the repulsive force in the direction of one base end. When the proximal end portion 23a is bent once, even if the first puncture needle 2a is further pushed into the body tissue, the proximal end portion 23a only bends, and the distal end of the first puncture needle 2a is left behind. It never enters. For this reason, puncture up to the inside of the organ 5 by the first puncture needle 2a can be avoided. Further, since the proximal end portion 23a bends when the distal end of the first puncture needle 2a reaches the surface of the organ 5, the operator of the catheter 1 can bend the distal end of the first puncture needle 2a by bending the proximal end portion 23a. Can grasp that the skin on the surface of the organ 5 has been punctured, so that the timing of withdrawing the first puncture needle 2a from the catheter 1 can be recognized.

  In FIG. 5, the case where the first puncture needle 2a is provided with the bent base end portion 23a has been described as an example. Similarly, the second puncture needle 4 is also more than a predetermined amount in the axial direction. A bending portion that bends when the above force is applied may be provided. In this case, if the bent portion of the second puncture needle 4 is bent by the repulsive force in the proximal direction of the catheter 1 applied when the distal end of the second puncture needle 4 reaches the inside of the tumor 6 inside the organ 5. Good. Thus, the operator of the catheter 1 can grasp that the distal end of the second puncture needle 4 has reached the inside of the tumor 6 due to the bending of the bent portion of the distal end of the second puncture needle 4. The timing for pulling out the needle 4 can be recognized. Of course, at least one of the first puncture needle and the second puncture needle is provided with a bent portion that bends when a predetermined amount or more of force is applied in the axial direction, and both the first puncture needle and the second puncture needle. In addition, a bending portion that bends when a predetermined amount or more of force is applied in the axial direction may be provided.

(Second Modification of Embodiment 1)
Next, a second modification of the first embodiment will be described. The catheter according to the second modification of the first embodiment includes a locking portion that locks the relative movement of the first puncture needle and the second puncture needle in the axial direction. This locking portion releases the engagement when a force of a predetermined amount or more separating the first puncture needle 2 and the second puncture needle 4 in the axial direction is applied. In the second modification of the first embodiment, by providing such a locking portion, the axial displacement between the first puncture needle and the second puncture needle at the time of puncture to the organ surface is prevented. In addition, the first puncture needle extraction process is facilitated.

  FIG. 6 is a cross-sectional view of the catheter according to the second modification of the first embodiment cut along the axial direction. As shown in FIG. 6 (1), in the catheter 1b according to the second modification, the locking portion is constituted by the first stopper 24b in the first puncture needle 2b and the second stopper 45b in the second puncture needle 4b. Composed.

  The first stopper 24b and the second stopper 45b are provided with recesses on the contact surfaces with which they are in contact with each other. Further, the second puncture needle 4b is provided with a spring 47 having one end fixed to the wall surface of the second stopper 45b on the distal end side of the recess. The spring 47 has a basic shape that protrudes in the direction of the first stopper 24b (upward in the figure), and relates to the relative movement of the first puncture needle 2 and the second puncture needle 4 in the axial direction. It functions as a locking part that stops.

  Similar to the catheter 1, as shown in FIG. 6 (2), after the tip of the first puncture needle 2b has punctured the surface of the organ 5, the first puncture needle 2b is removed in order to extract the first puncture needle 2b. It is slid in the proximal direction of the catheter 1 as indicated by an arrow Y2. In this case, the bottom surface 24c of the first stopper 24b also slides to the proximal direction side as indicated by the arrow Y2. Along with this, a force pushing downward in the figure is applied to the spring 47 by the bottom surface 24c slid and moved as indicated by the arrow Y2. When the first puncture needle 2b is slid so that the downward pressing force is larger than the protruding force of the spring 47, the spring 47 is moved to the bottom of the concave portion of the second stopper 45b (as indicated by the arrow Y9). It is deformed so as to be pushed in (downward in the figure). As a result, the spring 47 releases the locking with respect to the relative movement of the first puncture needle 2 and the second puncture needle 4 in the axial direction, and as shown by the arrow Y2b in FIG. The puncture needle 2b can be pulled out. Next, the catheter 1b may be further inserted into the organ 5 in a state where the tip of the second puncture needle 4b is exposed as indicated by an arrow Y3b.

(Third Modification of Embodiment 1)
Next, a third modification of the first embodiment will be described. FIG. 7 is a cross-sectional view of the catheter according to the third modification of the first embodiment cut along the axial direction. As shown in FIG. 7, the catheter 1d according to the third modification has a second puncture needle 4d having a low degree of sharpness on the outside of the housing 3d as an outer needle, and has a high degree of sharpness in the lumen of the housing 3d. One puncture needle 2d is provided as an inner needle.

  In the catheter 1d, the distal end opening surface 31d of the housing 3d is cut obliquely so that the inclined surface and the inclined surface of the second puncture needle 4 are continuous. As a result, since there is no gap between the tip of the first puncture needle 2d and the tip of the second puncture needle 4d, the tip of the first puncture needle 2d and the second puncture needle are punctured into the body of the catheter 1. It is possible to prevent a tissue piece or the like from entering between the tip of 4d.

  A recess is provided on the outer surface of the first puncture needle 2d so that a gap 26d is formed between the inner wall of the housing 3d and the outer surface of the first puncture needle 2d. As a result, when the first puncture needle 2d, which is the inner needle, is pulled out, the housing 3d is pulled by the friction in the pulling direction, the diameter of the housing 3 is reduced, and the first puncture needle 2d is pressed by the housing 3d and is difficult to pull out. Can be reduced. When the second puncture needle 4d, which is an outer needle, is pulled out, the housing 3d is pulled in the pulling direction due to friction and the diameter of the housing 3d is reduced, so that the housing 3d is removed from the inner wall of the second puncture needle 4d. Since the outer surface is separated, the second puncture needle 4d is not easily pulled out.

  Since the innermost first puncture needle does not need to accommodate a member therein, as shown in the catheter 1e in FIG. 8, the first puncture needle 2e having the closed tip 21e is used as the inner needle. It can also be used. Although not shown, a solid structure puncture needle may be used as the first puncture needle.

(Embodiment 2)
Next, a second embodiment will be described. FIG. 9 is a cross-sectional view of the catheter according to the second embodiment cut along the axial direction. FIG. 9 is a diagram illustrating a basic configuration of the catheter 201 according to the second embodiment, and illustrates a state in which the first puncture needle 202 and the second puncture needle 204 are assembled to the housing 3.

  As shown in FIG. 9, the catheter 201 has a part of the first puncture needle 202 with a high degree of sharpness at the tip and a second puncture needle 204 with a low degree of sharpness at the tip inside the lumen of the housing 3. All of the parts have a structure accommodated. That is, in the catheter 201, a part of the second puncture needle 204 is accommodated in the lumen of the housing 3, and a part of the first puncture needle 202 is accommodated in the lumen of the second puncture needle 204. . The catheter 201 has the first puncture needle 202 and the second puncture needle so that the distal end of the first puncture needle 202 is positioned closer to the distal end side of the catheter 201 than the distal end of the second puncture needle 204. The configuration in which 204 is assembled to the housing 3 is a basic configuration, and the first puncture needle 202 and the second puncture needle 204 can be pulled out, so that the same effects as in the first embodiment can be obtained.

  Further, in the catheter 201, a gap 246 is formed in which the inner wall of the lumen of the housing 3 and the outer surface of the second puncture needle 204 do not contact with each other, and sliding friction when the second puncture needle 204 is pulled out is reduced. Similarly, in the catheter 201, a gap 226 is formed in which the inner wall of the lumen of the second puncture needle 204 and the outer surface of the first puncture needle 202 are not in contact with each other. Reduced.

  Further, in the catheter 201, the diameter of the first puncture needle 202 and the diameter of the second puncture needle 204 are made smaller than the diameter of the casing 3, and the inside of the casing 3 to be placed in the living tissue is used. A first puncture needle 202 and a second puncture needle 204 that are pulled out after puncture are accommodated. Therefore, since the outer surface of the housing 3 and the living tissue are in direct contact with each other until the puncture needles are pulled out after the catheter 201 is punctured, the housing 3 and the living body are compared with the first embodiment. Adhesion with the tissue can be increased, and leakage of tissue secretions and tumor cells can be reduced.

  In the second embodiment, as in the catheter 201a shown in FIG. 10, the positions of the first puncture needle and the second puncture needle are interchanged, and a part of the first puncture needle is accommodated in the lumen of the housing 3. A part of the second puncture needle 204a may be accommodated in the lumen of one puncture needle 202a.

  Further, in the catheter 201, in order to reduce sliding friction when the first puncture needle 202a is pulled out, a recess is provided on the outer side of the first puncture needle 202a, and the first puncture needle 202a is assembled to the housing 3. A gap 226a is formed in which the outer surface of the first puncture needle 202a and the inner wall of the lumen of the housing 3 do not contact each other.

  In the catheter 201a, a basic configuration is formed by covering the outer side of the first puncture needle 202a having an outer diameter larger than the inner diameter of the casing 3 while expanding the casing 3. Accordingly, since the housing 3 is stretched and thinned, the overall diameter of the catheter 201 is reduced as compared with the case where the inner diameter of the housing 3 is the same as the outer diameter of the outer first puncture needle 202a. And puncture into the living tissue can be facilitated. Further, when the first puncture needle 202a is pulled out, the extension of the casing 3 is canceled and the inner wall of the casing 3 comes into contact with the outer surface of the second puncture needle 204a inside. As a result, the gap between the inner wall of the housing 3 and the outer surface of the second puncture needle 204a is eliminated, so that a tissue piece or the like does not enter between the housing 3 and the tip of the second puncture needle 202a.

  It should be noted that the catheters 201 and 201a may be further added with the bent portion or the locking portion described in the first and second modifications of the first embodiment to facilitate the puncture of the catheter into the body and the withdrawal of each puncture needle. Good.

(Embodiment 3)
Next, Embodiment 3 will be described. FIG. 11 is a cross-sectional view of the catheter according to the third embodiment cut along the axial direction. FIG. 11 is a diagram illustrating a basic configuration of the catheter 301 according to the third embodiment, and illustrates a state in which the first puncture needle 302 and the second puncture needle 304 are assembled to the housing 3.

  As shown in FIG. 11, the catheter 301 has a structure in which the housing 3 is accommodated on the innermost side. That is, in the catheter 301, a part of the second puncture needle 304 with a low tip sharpness is accommodated in the lumen of the first puncture needle 302 with a high tip sharpness. A part of the housing 3 is accommodated in the lumen. The catheter 301 has the first puncture needle 302 and the second puncture needle so that the distal end of the first puncture needle 302 is positioned closer to the distal end side of the catheter 201 than the distal end of the second puncture needle 304. Since the configuration in which 304 is assembled to the housing 3 is a basic configuration, and the first puncture needle 302 and the second puncture needle 304 can be pulled out, the same effects as in the first embodiment can be obtained.

  As described above, in the catheter according to the present invention, the first puncture needle is directly or indirectly attached to the housing so as to be slidable in the axial direction of the housing, and the distal end protrudes from the distal end of the housing toward the proximal end of the housing. The second puncture needle is directly or indirectly attached to the housing so as to be slidable in the axial direction of the housing, and differs from the first puncture needle in at least one of sharpness and rigidity, What is necessary is just to be able to slide from the position where the front-end | tip protruded from the front-end | tip of a housing | casing toward the base end of a housing, and to separate from a housing.

  Further, the distal end of the housing 3 needs to be positioned on the proximal side from the distal end of each puncture needle so as not to protrude from the distal end of each puncture needle and hinder puncture. In this catheter 301, since the housing 3 is disposed on the innermost side, the distal end 32a of the housing 3 is extended to the end of the inner wall where the tip of the second puncture needle 304 where the outer surface of the housing 3 comes into direct contact starts. Can be shifted to the tip side. Therefore, in the catheter 301, since the distal end of the housing 3 can be positioned on the distal end side as compared with the first and second embodiments, the housing 3 can be lengthened and a flexible design can be realized. Can do.

  Further, in the catheter 301, the distal end 32a of the housing 3 can be positioned on the distal end side as compared with the first and second embodiments, so that it is positioned on the outermost side as compared with the first and second embodiments. The distance L between the tip 321a of the first puncture needle 302 and the tip 32a of the housing 3 can be shortened. Here, when puncturing the surface of an organ with the first puncture needle, it is necessary to insert the distal end of the catheter until the distal end of the body is located under the skin of the organ. In the catheter 301, since the distance L between the distal end 321a of the first puncture needle 302 and the distal end 32a of the housing 3 can be made shorter than in the first and second embodiments, the degree of sharpness is higher than in the first and second embodiments. The degree of insertion of the first puncture needle 302 into the organ 5 can be reduced.

(First Modification of Embodiment 3)
Next, a first modification of the third embodiment will be described. FIG. 12 is a cross-sectional view of the catheter according to the first modification of the third embodiment cut along the axial direction. FIG. 12 (1) shows a basic configuration of a catheter 301a according to the first modification of the third embodiment. As shown in FIG. 12 (1), the catheter 301 a has a configuration in which the positions of the first puncture needle and the second puncture needle are interchanged as compared with the catheter 301. That is, in the catheter 301a, a part of the first puncture needle 302a having a high degree of tip sharpness is accommodated in the lumen of the second puncture needle 304a having a low degree of tip sharpness. A part of the housing 3 is accommodated in the lumen.

  The catheter 301a has a connection mechanism that connects the first puncture needle 302a and the second puncture needle 304a to each other. FIG. 13 is an exploded perspective view of the first puncture needle 302a and the second puncture needle 304a shown in FIG.

  As shown in FIGS. 12A and 13, the second puncture needle 304a located on the outermost side is formed with a through groove 348 in the axial direction. The through-groove 348 is a narrow portion having a narrow groove width after extending in the axial direction at a distance corresponding to the protruding portion of the first puncture needle 302a protruding from the second puncture needle 304a and then being bent in the circumferential direction. 348a. A substantially circular wide portion 348b is formed on the circumferential side of the narrow portion 348a. On the other hand, a protrusion 328 is formed on the outer surface of the first puncture needle 302a toward the outside. The protrusion 328 has a width capable of moving through the through groove 348.

  14 (1) and (2) are perspective views of the catheter 301a in each state shown in FIGS. 12 (1) and (2), and FIG. 15 is a cross-sectional view taken along the line AA in FIG. 14 (2). is there. As shown in FIGS. 12 (1) and 14 (1), in the basic configuration of the catheter 301a, the protrusion 328 of the first puncture needle 302a is located at the position P1 on the distal end side of the through groove 348 of the second puncture needle 304a. To position. As a result, the first puncture needle 302a and the second puncture needle 304a are positioned and connected so that the distal end position of the first puncture needle 302a is closer to the distal end side than the distal end position of the second puncture needle 304a. Will be.

  Then, as shown in FIGS. 12 (1) and 14 (1), the first puncture needle 302a is moved in the direction of the arrow Y31 on the proximal end side, thereby protruding from the distal end of the second puncture needle 304a. The tip of the first puncture needle 302a is housed inside the lumen of the second puncture needle 304a. With the movement of the first puncture needle 302a on the proximal end side, the protrusion 328 also moves in the through groove 348 toward the proximal end side as indicated by an arrow Y31a.

  Then, after the first puncture needle 302a is moved to the proximal side until the protrusion 328 comes into contact with the bent portion of the through groove 348, as shown in FIGS. The puncture needle 302a is rotated in the circumferential direction as indicated by an arrow Y32. By the rotation of the first puncture needle 302a, the protrusion 328 moves in the circumferential direction as shown by the arrow Y32a in FIGS. 14 (2) and 15 in the through groove 348, and the protrusion 328 elastically deforms the narrow portion 348a. And fit in the large width portion 348b. When the protrusion 328 is accommodated in the large width part 348b, as shown in FIG. 12 (2), the distal end position of the second puncture needle 304a is closer to the distal end side than the distal end position of the first puncture needle 302a. The first puncture needle 302a and the second puncture needle 304a are connected in a state where all the inclined portions of the tip 21 of the first puncture needle 302a are accommodated in the lumen of the second puncture needle 304a. It becomes. The protrusion 328 may exceed the narrow portion 348a by elastic deformation of the protrusion 328.

  The protrusion 328 and the through groove 348 functioning as the coupling mechanism are connected to the first puncture needle 302a and the first puncture needle 302a so that the distal end position of the first puncture needle 304a is closer to the distal end side than the distal end position of the second puncture needle 304a. The first state where the second puncture needle 304a is connected, and the first puncture needle 302a and the second puncture needle 304a so that the distal end position of the second puncture needle 304a is closer to the distal end side than the distal end position of the first puncture needle 302a. A transition is made between the second states connecting the two puncture needles 304a.

  When the housing 3 is completely placed in the tumor, the second puncture needle 302a and the first puncture needle 302a accommodated in the lumen of the second puncture needle 302a are shown in FIG. As shown by the arrow Y33 in FIG.

  Thus, in the catheter 301a, since the first puncture needle 302a and the second puncture needle 304a can be pulled out from the housing 3 at the same time, the puncture needle can be pulled out only once. It is possible to reduce the operation burden on the surgeon.

  In the first to third embodiments, the first puncture needle 2, 2a, 2b, 2e, 202, 202a, 302, 302a having a high degree of sharpness at the tip is used for coating the surface of the organ, The case where the second puncture needle 4, 4b, 4c, 4d, 204, 204a, 304, 304a having a low tip sharpness is used as an example for puncturing the inside or tumor has been described. By making the rigidity of the puncture needles 2, 2a, 2b, 2e, 202, 202a, 302, 302a higher than the rigidity of the second puncture needles 4, 4b, 4c, 4d, 204, 204a, 304, 304a Further, the puncture of the skin on the organ surface may be further facilitated.

  Of course, it is not necessary to change both the sharpness and rigidity of the tip between the first puncture needle and the second puncture needle. For example, as shown in the catheter 401 of FIG. 16, the tip 421 of the first puncture needle 402 and the tip 441 of the second puncture needle 404 are set to have approximately the same sharpness, and the first puncture needle is set. Even when the stiffness of the needle 402 is set to be higher than the stiffness of the second puncture needle, puncture of the surface of the organ and the puncture of the inside of the organ or tumor can be facilitated.

  Further, in Embodiments 1 to 3, the innermost puncture needle tip is illustrated as a shape in which the cylindrical tip is cut out from one direction. Also good.

(Embodiment 4)
Next, a fourth embodiment will be described. In the fourth embodiment, a case where the first puncture needle tip having a higher degree of sharpness than the second puncture needle tip is protruded from the tubular second puncture needle tip whose tip opening is closed will be described.

  FIG. 17 is an exploded perspective view of the catheter according to the fourth embodiment. As shown in FIG. 17, in the catheter according to the fourth embodiment, a part of the first puncture needle 502 is accommodated in the lumen of the housing 3. The second puncture needle 504 is formed by a tube 543 having a pointed tip and a tip opening portion closed by a closing member 541. The length of the tube 543 is longer than the length of the housing 3. FIG. 18 is a left side view of the second puncture needle 504 shown in FIG. As shown in FIG. 18, the closing member 541 at the distal end of the second puncture needle 504 is formed with two slits 549 that cross each other. The slit 549 communicates the inside and the outside of the second puncture needle 504.

  A part of the first puncture needle 502 is accommodated in the tube 543 of the second puncture needle 504. The first puncture needle 502 is assembled in a cross shape so that a plurality of blade members 522 are fitted to the slits 549 at the tip, and the sharpness of the tip 521 of the assembled blade member 522 is the second puncture. The sharpness of the tip of the needle 504 is higher. A linear member 523 such as a wire extending to the base end side is connected to the base end of the blade member 522. The linear member 523 has a smaller diameter than the lumen diameter of the tube 543. The length from the distal end to the proximal end of the first puncture needle 502 is set to be longer than the length from the distal end to the proximal end of the catheter 3.

  FIG. 19 is a perspective view of a catheter according to the fourth embodiment. First, the catheter 501 according to the fourth embodiment is housed in the lumen of the housing 3 so that the tip of the second puncture needle 504 protrudes from the opening at the tip of the housing 3 as shown in FIG. Is done. The first puncture needle 502 is inserted into the tube 543 from the proximal end side of the second puncture needle 504. The first puncture needle 502 is inserted into the tube 543 until a part of the blade member 522 at the distal end of the first puncture needle 502 protrudes by pushing open the slit 549 at the distal end of the second puncture needle 504. The That is, when the first puncture needle 502 is partially accommodated in the lumen of the second puncture needle 504, the tip 521 projects from the slit 549, so that the tip 521 projects from the tip of the housing 3. It becomes the position. Thus, the first puncture needle 502 and the second puncture needle 504 are assembled to the housing 3 such that the tip of the first puncture needle 502 protrudes from the tip of the second puncture needle 504. Basic configuration.

  Since the length from the distal end 521 to the proximal end of the first puncture needle 502 is set to be longer than the length from the distal end to the proximal end of the catheter 3, even in the basic configuration state, The proximal end of the linear member 523 of one puncture needle 502 holds the state of exiting from the tube 543. Therefore, after the skin puncture of the organ surface, the first puncture needle 502 is moved to the second puncture as shown in FIG. 19 (2) by moving the linear member 523 to the proximal end side as indicated by an arrow Y51. Pull out from the needle 504.

  20 is a cross-sectional view in the axial direction of the tip of the second puncture needle 504 shown in FIG. As shown in FIG. 20, in the second puncture needle 504, the closing member 541 has a hemispherical shape, and a slit 549 is formed by making a cross-shaped cut into this hemispherical. The slit 549 maintains a closed state by the elasticity of the closing member 541 when nothing is inserted. Further, an elastic member 550 is formed on the lower surface of the closing member 541 so as to be embedded in the tube 543. The elastic member 550 is also provided with a slit at the same position as the slit 549. Therefore, as shown in FIG. 20 (1), when the tip 521 of the first puncture needle 502 protrudes, the blade member 522 also in the slit of the elastic member 550 in addition to the slit 549 of the closing member 541 on the outer surface side. Therefore, even when the catheter 501 is punctured, the blade member 522 is not pushed back into the second puncture needle 504. 20 (2), when nothing is inserted into the slit 549, the slit of the elastic member 550 is also closed as indicated by an arrow due to elasticity, so that the slit 549 is reliably closed by the elastic member 550. Thus, it is possible to prevent a tissue piece or the like from entering the second puncture needle 502.

  When the distal end of the catheter 501 is inserted to the tumor, the second puncture needle 504 is moved into the housing 3 as shown in FIG. 19 (3) by moving the tube 543 to the proximal end side as indicated by an arrow Y52. Pull out from.

  Thus, even in the catheter 501 in which the first puncture needle tip having a higher degree of sharpness than the second puncture needle tip is projected from the tubular second puncture needle tip whose end opening is closed, the first puncture is also performed. The first puncture needle 502 and the second puncture needle 504 are assembled to the housing 3 so that the distal end of the needle 502 is positioned closer to the distal end side of the catheter 501 than the distal end of the second puncture needle 504. Since the configuration is a basic configuration and the first puncture needle 502 and the second puncture needle 504 can be pulled out, the same effects as in the first embodiment can be obtained.

  In the catheter according to the fourth embodiment, the slit shape of the second puncture needle tip may be set in correspondence with the first puncture needle tip shape. For example, as shown in FIG. 21, in the case where the tip of the first puncture needle is formed by a single blade member 522a having a pointed shape, the closing member 541a of the second puncture needle has this blade A single slit 549a may be formed in correspondence with the member 522a as shown in FIG. 22 so that the blade member 522a at the tip of the first puncture needle can protrude from the slit 549a.

  Note that the number of first puncture needles 502 is not limited to one and can be appropriately selected depending on the puncture target from a plurality of puncture needles with different degrees of sharpness.

1, 1a, 1b, 1d, 1e, 101, 201, 201a, 301, 301a, 401, 501 Catheter 2, 2a, 2b, 2d, 2e, 202, 202a, 302, 302a, 402, 502 First puncture needle 3, 3d rod 4, 4b, 4d, 204, 104, 204a, 304, 304a, 404, 504 second puncture needle 5 organ 6 tumor 22, 42 intermediate portion 23, 43 proximal portion 44 protruding portion 24, 24b, 45, 45b Stopper 47 Spring 328 Protrusion 348 Through groove 348a Narrow part 348b Wide part 522, 522a Blade member 523 Linear member 541, 541a Closure member 543 Tube 549, 549a Slit 550 Elastic member

Claims (12)

A catheter that is pierced into the biological tissue of a mammal, including a human,
An elongated tubular housing having a lumen inside;
First or indirectly attached to the housing so as to be slidable in the axial direction of the housing, the tip is slid toward the base end of the housing from a position protruding from the tip of the housing, and is separable from the housing. A puncture needle,
It is directly or indirectly attached to the casing so as to be slidable in the axial direction of the casing, and is different from the first puncture needle in at least one of sharpness and rigidity, and the tip of the casing is protruded from a position protruding from the tip of the casing. A second puncture needle slidable toward the proximal end and separable from the housing;
A catheter comprising: The first puncture needle and the second puncture needle have a tubular shape with a sharp tip,
The catheter according to claim 1, wherein central axes of the casing, the first puncture needle, and the second puncture needle are arranged substantially coaxially.   A protruding length of the first puncture needle tip from the tip of the case when the first puncture needle slides in the most distal direction with respect to the case, and the second puncture needle is the most distal end with respect to the case. The catheter according to claim 2, wherein the length of the second puncture needle tip protruding from the housing tip when sliding in the direction is different. The housing is at least partially housed in the lumen of the first puncture needle,
The catheter according to claim 2, wherein at least a part of the second puncture needle is accommodated in a lumen of the housing. The first puncture needle is at least partially housed in the lumen of the housing;
The catheter according to claim 2, wherein at least a part of the second puncture needle is accommodated in a lumen of the first puncture needle. The second puncture needle is at least partially housed in the lumen of the first puncture needle,
The catheter according to claim 2, wherein at least a part of the housing is accommodated in a lumen of the second puncture needle.   2. The catheter according to claim 1, wherein at least one of the first puncture needle and the second puncture needle has a bent portion that bends when a predetermined amount or more of force is applied in an axial direction. A locking portion for locking the axial relative movement of the first puncture needle and the second puncture needle;
The locking portion releases the locking when a force of a predetermined amount or more that separates the distal end of the first puncture needle and the distal end of the second puncture needle in the axial direction is applied. 2. The catheter according to 1. A connection mechanism for connecting the first puncture needle and the second puncture needle to each other;
The coupling mechanism connects the first puncture needle and the second puncture needle so that the distal end position of the first puncture needle is closer to the distal end side than the distal end position of the second puncture needle. The first puncture needle and the second puncture needle are connected to each other so that the tip position of the first puncture needle is closer to the tip side than the tip position of the first puncture needle. The catheter according to claim 1, which transitions between two states. The second puncture needle has a tubular shape with a pointed tip and a closed end opening, and has a slit communicating the inside and the outside of the second puncture needle at the closed end portion.
The first puncture needle is:
The second puncture needle is different from the second puncture needle in the sharpness of the tip, and a tip member fitted into the slit;
A linear member extending to the proximal end and connected to the distal member;
Have
The second puncture needle is at least partially housed in the lumen of the housing,
2. The catheter according to claim 1, wherein the tip member protrudes from the slit in a state where at least a part of the first puncture needle is accommodated in a lumen of the second puncture needle. The closed tip portion of the second puncture needle is formed by an outer surface member and an elastic member,
The catheter according to claim 10, wherein the slit is blocked by the elastic member in a state where nothing is inserted into the slit. A catheter insertion device used when a catheter having an elongated tubular casing having a lumen therein is inserted into a biological tissue of a mammal including a human,
First or indirectly attached to the housing so as to be slidable in the axial direction of the housing, the tip is slid toward the base end of the housing from a position protruding from the tip of the housing, and is separable from the housing. A puncture needle,
It is directly or indirectly attached to the casing so as to be slidable in the axial direction of the casing, and is different from the first puncture needle in at least one of sharpness and rigidity, and the tip of the casing is protruded from a position protruding from the tip of the casing. A second puncture needle slidable toward the proximal end and separable from the housing;
A catheter insertion device comprising:

Images