catheter

Abstract

The present invention provides a catheter that can improve the efficiency of delivering administered substances to the treatment site via intravascular administration without blocking blood flow. [Solution] The catheter according to the present disclosure comprises a tubular body having an administration lumen through which a substance to be administered to a living body can flow, the side wall of the tubular body is partitioned with an outlet hole that communicates with the administration lumen and can discharge the administered substance, and an inlet hole that communicates with the administration lumen and can allow blood to flow into the administration lumen, located at the proximal end of the tubular body in the longitudinal direction from the outlet hole, and the tip surface of the tubular body is partitioned with a tip opening that can discharge the blood flowing into the administration lumen from the inlet hole.

Description

[Technical Field]

[0001] The present disclosure relates to catheters. [Background Art]

[0002] Conventionally, there is known a procedure of administering an administration substance such as a drug or a cell to a predetermined region in a blood vessel, and retaining the administered substance in the predetermined region. The administered substance is supplied, for example, through the surrounding vascular endothelium to a treatment target site such as a diseased tissue. Patent Document 1 describes a balloon catheter used for this type of procedure. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2004 / 045702 [Summary of the Invention] [Problems to be Solved by the Invention]

[0004] In the balloon catheter described in Patent Document 1, an administration substance such as a drug or a cell is administered to the outside of the catheter body through an injection port of the catheter body. However, in the balloon catheter described in Patent Document 1, blood flow in the blood vessel is temporarily blocked by two balloons arranged side by side in the axial direction. The administration substance is administered into the blood vessel through the injection port of the catheter body located between these two balloons. Since the blood flow is blocked, it is possible to improve the supply efficiency with which the administration substance administered into the blood vessel is supplied through the vascular endothelium to the treatment target site such as a diseased tissue. On the other hand, in consideration of the physical burden on the patient, it is preferable that blood flow is maintained.

[0005] An object of the present disclosure is to provide a catheter capable of improving the supply efficiency of an administration substance administered into a blood vessel to a treatment target site without blocking blood flow. [Means for Solving the Problems]

[0006] A catheter as a first aspect of this disclosure is (1) It comprises a tubular body that has an internally partitioned administration lumen through which the substance to be administered to the living body can flow, The side wall of the tubular body has, A discharge port that communicates with the administration lumen and allows the administered substance to be discharged, At a position toward the proximal end in the longitudinal direction of the tubular body from the discharge hole, an inlet hole is provided which communicates with the administration lumen and allows blood to flow into the administration lumen. The catheter is characterized in that the tip surface of the tubular body is partitioned with a tip opening that allows the blood flowing in from the inlet hole to the administration lumen to be discharged.

[0007] A catheter as one embodiment of the present disclosure is (2) The tubular body is A tubular body and It comprises a discharge pipe section connected to the tip of the tubular body, The administration lumen extends across the tubular body and the discharge pipe section. The aforementioned discharge hole is partitioned in the side wall of the discharge pipe section. The inlet is partitioned in the side wall of the tubular body, The aforementioned tip opening is partitioned on the tip surface of the discharge pipe section, The discharge tube portion is the catheter described in (1) above, which is foldable so as to extend along the longitudinal direction of the tubular body.

[0008] A catheter as one embodiment of the present disclosure is (3) The aforementioned discharge pipe section is The discharge pipe body has a side wall that demarcates the discharge hole, It comprises a tubular joint portion located between the tubular body and the discharge pipe body, and having less bending rigidity than the discharge pipe body, The discharge pipe body is the catheter described in (2) above, wherein the tubular joint portion can be bent and deformed so as to extend along the longitudinal direction of the tubular body.

[0009] A catheter as one embodiment of the present disclosure is (4) The discharge pipe body is made of a porous material. The discharge hole is a hole formed in the discharge tube body, as described in (3) above.

[0010] A catheter as one embodiment of the present disclosure is (5) When the aforementioned discharge hole is referred to as the first discharge hole, the discharge pipe body as the first discharge pipe body, and the tubular joint portion as the first tubular joint portion, The aforementioned discharge pipe section is The second discharge pipe body has a second discharge hole partitioned in its side wall, It comprises a second tubular joint located between the first discharge pipe body and the second discharge pipe body, having less bending rigidity than the second discharge pipe body, The second discharge pipe body is the catheter described in (3) or (4) above, wherein the second tubular joint portion is bent and deformed so as to extend along the extending direction of the first discharge pipe body.

[0011] A catheter as one embodiment of the present disclosure is (6) The first discharge pipe body is foldable from the distal side to the proximal side by the first tubular joint, The second discharge tube body is the catheter described in (5) above, which can be folded back from the proximal side to the distal side by the second tubular joint.

[0012] A catheter as one embodiment of the present disclosure is (7) The catheter according to (6) above, wherein the discharge pipe section includes a third discharge pipe main body that connects the tubular main body and the first tubular joint section and defines a third discharge hole in a side wall thereof.

[0013] A catheter according to one embodiment of the present disclosure, (8) The catheter according to (6) or (7) above, comprising a guide member having a distal end portion connected to the second tubular joint portion and capable of guiding the folding operation of the first discharge pipe main body and the second discharge pipe main body by moving along the tubular main body.

[0014] A catheter according to one embodiment of the present disclosure, (9) The catheter according to any one of (5) to (8) above, wherein the first discharge pipe main body and the second discharge pipe main body include a connecting portion connectable by magnetic force in a state where the second discharge pipe main body is folded back so as to extend along the extending direction of the first discharge pipe main body. Effects of the Invention

[0015] According to the present disclosure, it is possible to provide a catheter capable of improving the supply efficiency of an administered substance administered into a blood vessel to a treatment target site without blocking blood flow. Brief Description of Drawings

[0016] [Figure 1] It is a diagram showing a catheter as one embodiment of the present disclosure. [Figure 2] It is a cross-sectional view taken along line I-I in FIG. 1. [Figure 3] It is a cross-sectional view taken along line II-II in FIG. 1. [Figure 4] It is a cross-sectional view taken along line III-III in FIG. 1. [Figure 5] It is a diagram showing a state where the discharge pipe section of the tubular body of the catheter shown in FIG. 1 has reached a treatment target region in a blood vessel. [Figure 6]This diagram shows the operation to fold back the discharge pipe section from the state shown in Figure 5. [Figure 7] This figure shows the state after the discharge pipe section has been folded back following the operation shown in Figure 6. [Figure 8] Figure 7 shows the state in which the administered substance is being administered intravascularly. [Figure 9] This figure shows the state after the administration of the substance shown in Figure 8 has been completed, with the discharge tube extended. [Figure 10] This figure shows an example of a folded configuration for the discharge pipe section. [Modes for carrying out the invention]

[0017] Hereinafter, embodiments of the catheter relating to this disclosure will be described with reference to the drawings. In each figure, identical components are denoted by the same reference numerals.

[0018] Figure 1 shows a catheter 100 as one embodiment of the catheter according to this disclosure. Figure 2 is a cross-sectional view of the catheter 100 at the position of line II shown in Figure 1. Figure 3 is a cross-sectional view of the catheter 100 at the position of line II-II shown in Figure 1. Figure 4 is a cross-sectional view of the catheter 100 at the position of line III-III shown in Figure 1. The catheter 100 can be inserted percutaneously into the blood vessels of a living body such as a patient.

[0019] As shown in Figure 1, the catheter 100 comprises a tubular body 10 and a hub 20 to which the proximal end of the tubular body 10 is fixed. The catheter 100 internally partitions an administration lumen 101 through which a substance to be administered to a living organism can flow, spanning the tubular body 10 and the hub 20. The substance to be administered may be, for example, a drug, cells, extracellular vesicles, etc. The substance to be administered may flow through the administration lumen 101 on its own, or it may flow through the administration lumen 101 in a state mixed with a liquid.

[0020] Hereinafter, in the catheter 100, the direction parallel to the central axis O of the tubular body 10 will be referred to as "longitudinal direction A of the tubular body 10" or simply "longitudinal direction A". Furthermore, in longitudinal direction A, the direction from the proximal end to the distal end of the tubular body 10 may be simply referred to as "proximal side A1", and the direction from the distal end to the proximal end of the tubular body 10 may be simply referred to as "proximal side A2".

[0021] As shown in Figures 1, 2, and 4, the side wall of the tubular body 10 is partitioned with an outlet hole 101a and an inlet hole 101b. Also, as shown in Figure 1, the tip surface of the tubular body 10 is partitioned with a tip opening 101c.

[0022] The discharge port 101a communicates with the administration lumen 101 and allows for the discharge of the administered substance. The administered substance is administered within the blood vessels of the living body. In other words, the administered substance is administered from the administration lumen 101 through the discharge port 101a into the blood vessels outside the tubular body 10. The administered substance is supplied to the target area for treatment, such as diseased tissue, through the vascular endothelium. As will be described in detail later, the discharge port 101a in this embodiment is a hole formed in a porous body. In Figure 4, for the sake of explanation, the discharge port 101a is shown as a hole extending radially in the radial direction of the tubular body 10, but any hole that penetrates from the inner surface to the outer surface of the tubular body 10 is acceptable, and its direction of extension is not limited to the radial direction shown in Figure 4.

[0023] In the catheter 100 of this embodiment, the administered substance is supplied to the administration lumen 101 from a supply device connected to the connection port 20a of the hub 20. The administered substance supplied from the connection port 20a of the hub 20 is administered intravascularly through the discharge port 101a of the tubular body 10, as described above.

[0024] The inlet port 101b is located at position A2 on the proximal end side of the tubular body 10 in the longitudinal direction A, and is in communication with the administration lumen 101. With the tubular body 10 inserted into the blood vessel, blood can flow into the administration lumen 101 through the inlet port 101b.

[0025] The tip opening 101c allows blood flowing into the administration lumen 101 from the inlet hole 101b to be discharged.

[0026] Therefore, with the catheter 100, the administered substance can be delivered into the blood vessel from the delivery lumen 101 through the discharge port 101a. Furthermore, with the catheter 100, while the tubular body 10 is inserted into the blood vessel, blood can flow into the delivery lumen 101 from the inlet port 101b located at A2 proximal to the discharge port 101a. The blood that flows into the delivery lumen 101 from the inlet port 101b flows out into the blood vessel through the tip opening 101c located at A1 distal to the discharge port 101a. In other words, with the catheter 100, the administered substance can be delivered into the blood vessel without temporarily blocking the blood flow within the blood vessel. In addition, the discharge port 101a is partitioned off the side wall of the tubular body 10. Therefore, the administered substance is discharged from the discharge port 101a in a direction intersecting the direction of blood flow within the blood vessel. As a result, the administered substance is discharged towards the surrounding vascular endothelium. This improves the efficiency of supplying the administered substance to the target area such as diseased tissue through the vascular endothelium. Thus, with the catheter 100, it is possible to improve the efficiency of supplying administered substances to the treatment site via intravascular administration without blocking blood flow.

[0027] Further details of the catheter 100 of this embodiment will be described below.

[0028] As shown in Figure 1, the tubular body 10 of this embodiment comprises a tubular body 11, a discharge pipe section 12 connected to the tip side A1 of the tubular body 11, and a guide member 13. In the tubular body 10 of this embodiment, the administration lumen 101 extends across the tubular body 11 and the discharge pipe section 12.

[0029] In this embodiment, the discharge hole 101a is located in the side wall of the discharge pipe section 12. The inlet hole 101b is located in the side wall of the tubular body 11. Furthermore, the tip opening 101c is located on the tip surface of the discharge pipe section 12. In other words, in this embodiment, the tip surface of the discharge pipe section 12 is the tip surface of the tubular body 10.

[0030] As shown in Figures 1 to 3, the side wall of the tubular body 11 in this embodiment is partitioned with an insertion lumen 11a through which the guide member 13 can be inserted. The insertion lumen 11a in this embodiment is partitioned within the wall of the side wall that partitions the administration lumen 101 of the tubular body 11. As shown in Figure 3, the tubular body 11 in this embodiment has a through hole 11a1 in its side wall that communicates with the insertion lumen 11a and through which the guide member 13 passes. The through hole 11a1 in this embodiment is located at the tip side A1 from the inlet hole 101b. The guide member 13 extends from the insertion lumen 11a to the outside of the tubular body 11 through the through hole 11a1. The tip of the guide member 13 is connected to a second tubular joint 15b, which will be described later.

[0031] The discharge pipe section 12 of this embodiment is foldable so as to extend along the longitudinal direction of the tubular body 11 (the longitudinal direction A of the tubular body 10 at the position of the tubular body 11). As will be described in detail later, the discharge pipe section 12 of this embodiment is configured to be foldable twice so as to extend along the longitudinal direction of the tubular body 11 (see Figures 7 and 8).

[0032] More specifically, the discharge pipe section 12 of this embodiment comprises a discharge pipe body 14 and a tubular joint section 15. The discharge pipe body 14 can be folded back so as to extend along the longitudinal direction of the tubular body 11 (the longitudinal direction A of the tubular body 10 at the position of the tubular body 11) by bending deformation of the tubular joint section 15.

[0033] The discharge tube body 14 has a discharge hole 101a demarcated in its side wall. The discharge tube body 14 in this embodiment is a porous material. The discharge hole 101a in this embodiment is a hole formed in the discharge tube body 14. As shown in Figure 4, the hole, which serves as the discharge hole 101a, penetrates from the inner surface to the outer surface of the discharge tube body 14. Multiple holes are formed in the discharge tube body 14 in this embodiment. Therefore, the discharge tube body 14 can discharge the administered substance into the blood vessels outside through the multiple holes.

[0034] However, the discharge holes 101a do not have to be holes formed in a porous material. The discharge holes 101a may be holes such as perforations formed in the side wall of the discharge pipe body, which is made of a solid tubular portion. Furthermore, the number of holes that serve as discharge holes 101a formed in the side wall of the discharge pipe body, which is made of a solid tubular portion, is not particularly limited. There may be only one hole or multiple holes that serve as discharge holes 101a. The number of holes that serve as discharge holes 101a may be designed appropriately, taking into consideration the cross-sectional area of ​​the holes, etc.

[0035] The tubular joint section 15 is located between the tubular body 11 and the discharge pipe body 14. Furthermore, the tubular joint section 15 has less bending rigidity than the discharge pipe body 14. In other words, the discharge pipe section 12 in this embodiment is configured to be more easily deformed by bending at the position of the tubular joint section 15 than at the position of the discharge pipe body 14.

[0036] Furthermore, as shown in Figure 1, the discharge pipe section 12 of this embodiment comprises a plurality of discharge pipe bodies 14 and a plurality of tubular joint sections 15. More specifically, the discharge pipe section 12 of this embodiment comprises three discharge pipe bodies 14 and two tubular joint sections 15. For the sake of explanation, among the three discharge pipe bodies 14, the discharge pipe body 14 located in the middle of the longitudinal direction A will be referred to as the "first discharge pipe body 14a". The discharge pipe body 14 located at the tip side A1 of the longitudinal direction A will be referred to as the "second discharge pipe body 14b". Furthermore, the discharge pipe body 14 located at the base side A2 of the longitudinal direction A will be referred to as the "third discharge pipe body 14c". Furthermore, of the two tubular joint sections 15, the tubular joint section 15 located at the base end A2 is described as the "first tubular joint section 15a," and the tubular joint section 15 located at the tip end A1 is described as the "second tubular joint section 15b." In this embodiment, the tubular body 10 is connected in the following order from the base end A2 to the tip end A1 in the longitudinal direction A: third discharge pipe body 14c, first tubular joint section 15a, first discharge pipe body 14a, second tubular joint section 15b, and second discharge pipe body 14b. If the first discharge pipe body 14a, second discharge pipe body 14b, and third discharge pipe body 14c are not particularly distinguished, they are simply described as "discharge pipe body 14." Also, if the first tubular joint section 15a and second tubular joint section 15b are not particularly distinguished, they are simply described as "tubular joint section 15."

[0037] Each of the first discharge pipe body 14a, the second discharge pipe body 14b, and the third discharge pipe body 14c has a discharge hole 101a partitioned in its side wall. For the sake of explanation, the discharge hole 101a partitioned in the side wall of the first discharge pipe body 14a will be referred to as "first discharge hole 101a1". The discharge hole 101a partitioned in the side wall of the second discharge pipe body 14b will be referred to as "second discharge hole 101a2". Furthermore, the discharge hole 101a partitioned in the side wall of the third discharge pipe body 14c will be referred to as "third discharge hole 101a3". However, if there is no particular distinction between the first discharge hole 101a1, the second discharge hole 101a2, and the third discharge hole 101a3, they will simply be referred to as "discharge hole 101a".

[0038] In this embodiment, the first tubular joint portion 15a is located between the tubular body 11 and the first discharge pipe body 14a. More specifically, in this embodiment, the first tubular joint portion 15a is located between the third discharge pipe body 14c and the first discharge pipe body 14a. Furthermore, in this embodiment, the first tubular joint portion 15a has less bending rigidity than the first discharge pipe body 14a. Moreover, in this embodiment, the first tubular joint portion 15a has less bending rigidity than the third discharge pipe body 14c. Therefore, in this embodiment, the first discharge pipe body 14a can be folded back to extend along the longitudinal direction of the tubular body 11 (the longitudinal direction A of the tubular body 10 at the position of the tubular body 11) by bending deformation of the first tubular joint portion 15a. Furthermore, the first discharge pipe body 14a in this embodiment can be folded back so as to extend along the extending direction of the third discharge pipe body 14c (the longitudinal direction A of the tubular body 10 at the position of the third discharge pipe body 14c) by bending deformation of the first tubular joint portion 15a. Details of this will be described later (see Figures 7 and 8).

[0039] Furthermore, the second tubular joint portion 15b in this embodiment is located between the tubular body 11 and the second discharge pipe body 14b. More specifically, the second tubular joint portion 15b in this embodiment is located between the first discharge pipe body 14a and the second discharge pipe body 14b. Also, the second tubular joint portion 15b in this embodiment has less bending rigidity than the second discharge pipe body 14b. Moreover, the second tubular joint portion 15b in this embodiment has less bending rigidity than the first discharge pipe body 14a and the third discharge pipe body 14c. Therefore, the second discharge pipe body 14b in this embodiment can be folded back to extend along the extending direction of the first discharge pipe body 14a (the longitudinal direction A of the tubular body 10 at the position of the first discharge pipe body 14a) by bending deformation of the second tubular joint portion 15b. Furthermore, the second discharge pipe body 14b of this embodiment can be folded back to extend along the longitudinal direction of the tubular body 11 (the longitudinal direction A of the tubular body 10 at the position of the tubular body 11) by bending deformation of the first tubular joint portion 15a and the second tubular joint portion 15b. Details of this will be described later (see Figures 7 and 8).

[0040] More specifically, the first discharge tube body 14a of this embodiment can be folded back from the distal side to the proximal side by the first tubular joint portion 15a. Similarly, the second discharge tube body 14b of this embodiment can be folded back from the proximal side to the distal side by the second tubular joint portion 15b. Details of this will be described later (see Figures 7 and 8). The term "distal side" refers to the insertion direction when the catheter 100 is inserted into a blood vessel. The term "proximal side" refers to the withdrawal direction when the catheter 100 is withdrawn from a blood vessel. In other words, the withdrawal direction is the opposite of the insertion direction.

[0041] Furthermore, as shown in Figure 1, the first discharge pipe body 14a and the second discharge pipe body 14b of this embodiment are provided with a connecting portion 16 that can be connected by magnetic force, with the second discharge pipe body 14b folded back so as to extend along the extending direction of the first discharge pipe body 14a (the longitudinal direction A of the tubular body 10 at the position of the first discharge pipe body 14a). Specifically, the connecting portion 16 of this embodiment comprises a first magnetic pole portion 16a provided on the first discharge pipe body 14a and a second magnetic pole portion 16b provided on the second discharge pipe body 14b. One of the first magnetic pole portion 16a and the second magnetic pole portion 16b is the positive pole, and the other is the negative pole. As a result, the first magnetic pole portion 16a and the second magnetic pole portion 16b can be connected by attractive force. The first magnetic pole portion 16a may be attached, for example, to the inner surface of the first discharge pipe body 14a. The second magnetic pole portion 16b may also be attached, for example, to the inner surface of the second discharge pipe body 14b.

[0042] Furthermore, as shown in Figure 1, the first discharge pipe body 14a and the third discharge pipe body 14c of this embodiment are provided with a connecting portion 17 that can be connected by magnetic force, with the first discharge pipe body 14a folded back so as to extend along the extending direction of the third discharge pipe body 14c (the longitudinal direction A of the tubular body 10 at the position of the third discharge pipe body 14c). The configuration of the connecting portion 17 is the same as that of the connecting portion 16 described above. Specifically, the connecting portion 17 of this embodiment comprises a first magnetic pole portion 17a provided on the third discharge pipe body 14c and a second magnetic pole portion 17b provided on the first discharge pipe body 14a. One of the first magnetic pole portion 17a and the second magnetic pole portion 17b is the positive pole and the other is the negative pole. As a result, the first magnetic pole portion 17a and the second magnetic pole portion 17b can be connected by attractive force. The first magnetic pole portion 17a may be attached, for example, to the inner surface of the third discharge pipe body 14c. The second magnetic pole portion 17b may also be attached, for example, to the inner surface of the first discharge pipe body 14a.

[0043] In this embodiment, it is preferable that the first magnetic pole portion 16a and the second magnetic pole portion 17b of the first discharge pipe body 14a have the same magnetic poles that generate a repulsive force between them. By doing so, it is possible to suppress deformation of the first discharge pipe body 14a that would cause it to collapse due to an attractive force generated between the first magnetic pole portion 16a and the second magnetic pole portion 17b. Therefore, in order to suppress the aforementioned collapse, the second discharge pipe body 14b may further include, for example, a magnetic pole portion having the same magnetic pole as the second magnetic pole portion 16b. Similarly, the third discharge pipe body 14c may also further include, for example, a magnetic pole portion having the same magnetic pole as the first magnetic pole portion 17a in order to suppress the aforementioned collapse.

[0044] In this embodiment, the discharge pipe section 12 comprises three discharge pipe bodies 14 and two tubular joint sections 15, but is not limited to this configuration. The discharge pipe section 12 may also comprise, for example, only one discharge pipe body 14 and only one tubular joint section 15 located between this single discharge pipe body 14 and the tubular body 11. In other words, the discharge pipe section 12 may comprise only one set of discharge pipe bodies 14 and tubular joint sections 15. Thus, the number of sets of discharge pipe bodies 14 and tubular joint sections 15 in the discharge pipe section 12 is not particularly limited. However, when one set of discharge pipe body 14 and tubular joint section 15 is defined as one discharge pipe body 14 and tubular joint section 15 connected to the base end A2 of the discharge pipe body 14, it is preferable that the discharge pipe section 12 comprises an even number of sets of discharge pipe bodies 14 and tubular joint sections 15. In this way, the flow of blood flowing out from the tip opening 101c and the flow of blood flowing from the tubular body 11 into the discharge pipe section 12 can be made to be in the same direction. In other words, the flow of blood flowing out from the tip opening 101c can be aligned with the direction of blood flow within the blood vessel. The discharge pipe section 12 in this embodiment comprises a total of two sets of discharge pipe bodies 14 and tubular joint sections 15 (one set consisting of a first discharge pipe body 14a and a first tubular joint section 15a, and one set consisting of a second discharge pipe body 14b and a second tubular joint section 15b, for a total of two sets). In this embodiment, the third discharge pipe body 14c is connected to the tip side A1 of the tubular body 11 and connects the tubular body 11 and the first tubular joint section 15a, but the configuration is not limited to this. The first tubular joint section 15a may also be connected to the tip side A1 of the tubular body 11. In other words, either the discharge pipe body 14 or the tubular joint portion 15 may be connected to the tip A1 of the tubular body 11.

[0045] The tubular body 11 of the tubular body 10 is preferably formed from a flexible material, but the material is not particularly limited. Examples of constituent materials include various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polyimide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based materials, and combinations of one or more of these (polymer alloys, polymer blends, laminates, etc.) can also be used. In addition, a hydrophilic lubricating coating layer that exhibits lubricity when wet may be placed on the outer surface of the tubular body 11.

[0046] The discharge tube portion 12 of the tubular body 10 may be formed from a flexible material integral with the tubular body 11. However, it is preferable to form the solid tubular body 11 and the porous discharge tube portion 12 separately and then join them. Examples of porous materials for the porous discharge tube portion 12 include synthetic resins or porous synthetic fibers. Examples of constituent materials for the porous discharge tube portion 12 include polyester, polyamide, polypropylene, polyethylene, polyurethane, polyvinyl chloride, acrylonitrile, styrene-based elastomer, polyethersulfone (PES), polysulfone (PS), and regenerated cellulose. The pores as discharge holes 101a formed in the porous discharge tube portion 12 only need to be large enough for the administered substance to pass through, and may be appropriately changed depending on the type of administered substance. If the administered substance is, for example, an extracellular vesicle, it is preferable that the cross-sectional area of ​​the discharge holes 101a be 100 nm or more. Furthermore, if the administered substance is, for example, cells, the cross-sectional area of ​​the efflux pore 101a is preferably 10 to 50 μm or more.

[0047] Furthermore, in the case where the discharge pipe section 12 comprises a discharge pipe body 14 and a tubular joint section 15, as in this embodiment, it is preferable that the discharge pipe body 14 be porous, as described above. The tubular joint section 15 only needs to have a configuration that is less bending rigid than the discharge pipe body 14, and the tubular joint section 15 may be formed integrally with the porous discharge pipe body 14, for example. In this case, the bending rigidity of the tubular joint section 15 may be made smaller than that of the discharge pipe body 14, for example, by making the wall thickness thinner than that of the discharge pipe body 14. However, the tubular joint section 15 may be formed from a different material than the discharge pipe body 14 and joined to the discharge pipe body 14. In this case, it is preferable that the tubular joint section 15 be formed from a flexible material, similar to the tubular body 11. Examples of constituent materials for the tubular joint section 15 include the constituent materials listed above as constituent materials for the tubular body 11. Furthermore, since the tubular joint portion 15 is not intended to be adjacent to the vascular endothelium, it is preferable that it be formed from a solid material rather than a porous material. The tubular joint portion 15 may be, for example, a solid tube made of rubber that is easily bendable.

[0048] As shown in Figure 1, the tip of the guide member 13 in this embodiment is connected to the second tubular joint portion 15b. Also, as shown in Figure 1, the guide member 13 in this embodiment is inserted through the insertion lumen 11a of the tubular body 11, and its base end protrudes from the hub 20. Therefore, the guide member 13 in this embodiment can move the insertion lumen 11a in the longitudinal direction A by manipulating the base end protruding from the hub 20. As a result, the guide member 13 in this embodiment can guide the folding operation of the first discharge pipe body 14a and the second discharge pipe body 14b by moving along the tubular body 11. Details of this will be described later (see Figures 5 to 7).

[0049] Next, with reference to Figures 5 to 9, an example of a procedure for administering substance X into a blood vessel BV using a catheter 100 will be described. Figure 5 shows the state in which the tubular body 10 of the catheter 100 is inserted into the blood vessel BV of the body, and the discharge tube portion 12 of the tubular body 10 has reached the vicinity of the treatment target area such as lesion tissue (hereinafter referred to as the "treatment target area"). Figure 6 shows the operation to fold back the discharge tube portion 12 from the state shown in Figure 5. Figure 7 shows the state in which the discharge tube portion 12 has been folded back by the operation shown in Figure 6. Figure 8 shows the state in which, in the state shown in Figure 7, the administered substance X is flowing through the administration lumen 101, and the administered substance X is being discharged from the administration lumen 101 through the discharge hole 101a. In other words, Figure 8 shows the state in which the administered substance X is being administered into the blood vessel BV. Figure 9 shows the state in which the discharge tube portion 12 is extended from the folded state in order to remove the tubular body 10 from the body after the administration of the administered substance X shown in Figure 8 is completed.

[0050] As shown in Figure 5, the tubular body 10 of the catheter 100 in this embodiment is delivered into the blood vessel BV with the discharge tube portion 12 not folded back relative to the tubular body 11. The tubular body 10 may be delivered within the blood vessel BV along, for example, a guidewire GW (see the dashed line in Figure 5).

[0051] As shown in Figure 6, after the discharge tube portion 12 of the tubular body 10 reaches the treatment area within the blood vessel BV, the guide member 13 can be manipulated to deform the discharge tube portion 12 so that it folds back. Specifically, the proximal end of the guide member 13 that protrudes from the hub 20 is moved proximal (see the white arrow in Figure 6). This allows the discharge tube portion 12 to be deformed so that the second tubular joint portion 15b, which is connected to the tip of the guide member 13, moves proximal. Specifically, as shown in Figure 7, the first discharge tube body 14a is folded back from the distal side to the proximal side by the first tubular joint portion 15a. Also, as shown in Figure 7, the second discharge tube body 14b is folded back from the proximal side to the distal side by the second tubular joint portion 15b. As a result, in this embodiment, the blood flowing through the tubular body 11, the third discharge pipe body 14c, and the second discharge pipe body 14b is in a direction approximately equal to the blood flow direction of the blood vessel BV. In contrast, the blood flowing through the first discharge pipe body 14a in this embodiment is in the opposite direction to the blood flow direction of the blood vessel BV. Thus, in this embodiment, the discharge pipe section 12 can be deformed so that both the first tubular joint section 15a and the second tubular joint section 15b are bent by operating the guide member 13.

[0052] By deforming the discharge tube portion 12 so as to fold back within the blood vessel BV, the extended length of the discharge tube portion 12 in the treatment area within the blood vessel BV can be increased. As a result, as shown in Figure 8, the amount of administered substance X discharged from the discharge port 101a of the discharge tube portion 12 in the treatment area within the blood vessel BV can be increased. Furthermore, by deforming the discharge tube portion 12 so as to fold back within the blood vessel BV, the discharge tube portion 12 overlaps radially, bringing the side walls of the discharge tube portion 12 closer to the vascular endothelium surrounding the treatment area. As a result, the administered substance X discharged from the discharge port 101a partitioned in the side walls of the discharge tube portion 12 is more easily taken up by the vascular endothelium surrounding the treatment area, thereby further improving the efficiency of the supply of administered substance X to the treatment area.

[0053] On the other hand, as the discharge tube portion 12 deforms so as to fold back within the blood vessel BV, the cross-sectional area of ​​the flow path within the blood vessel BV decreases. Furthermore, as the discharge tube portion 12 deforms so as to fold back within the blood vessel BV, for example as shown in Figure 10, the side walls of the discharge tube portion 12 come into contact with each other, and the side walls of the discharge tube portion 12 come into contact with the inner surface of the blood vessel BV, potentially resulting in a state where the blood vessel BV is substantially occluded by the discharge tube portion 12. In contrast, the catheter 100 has an inlet hole 101b and a tip opening 101c in the tubular body 10. Therefore, even if the blood vessel BV is substantially occluded by the folding of the discharge tube portion 12, blood flow can be maintained using the administration lumen 101 of the tubular body 10.

[0054] Furthermore, as shown in Figures 7 and 8, the first discharge pipe body 14a and the second discharge pipe body 14b of this embodiment are connected by a connecting portion 16. This makes it easier to maintain the folded state of the first discharge pipe body 14a and the second discharge pipe body 14b. Moreover, as shown in Figures 7 and 8, the third discharge pipe body 14c and the first discharge pipe body 14a of this embodiment are connected by a connecting portion 17. This makes it easier to maintain the folded state of the third discharge pipe body 14c and the first discharge pipe body 14a.

[0055] As shown in Figure 9, after the administration of substance X is complete, the guide member 13 is operated again. By moving the guide member 13 distally (see the white arrow in Figure 9), the discharge tube 12 can be extended again from the folded state. This allows the tubular body 10 to be removed from the body.

[0056] The catheter relating to this disclosure is not limited to the specific configuration shown in the embodiments described above, and various modifications, changes, and combinations are possible as long as they do not deviate from the scope of the claims. For example, in Figures 7 and 8, for the sake of explanation, the first discharge tube body 14a, the second discharge tube body 14b, and the third discharge tube body 14c are shown folded so as to be stacked in three layers in the radial direction of the blood vessel, but the catheter is not limited to such a folded configuration. As shown in Figure 10, the first discharge tube body 14a, the second discharge tube body 14b, and the third discharge tube body 14c may be folded, for example, while shifting their positions in the circumferential direction of the blood vessel. [Industrial applicability]

[0057] This disclosure relates to catheters. [Explanation of Symbols]

[0058] 10: Tubular body 11: Tubular body 11a: Insertion lumens 11a1: Passing hole 12: Discharge pipe part 13: Guide member 14: Discharge pipe body 14a: 1st discharge pipe body 14b: 2nd discharge pipe body 14c: Third discharge pipe body 15: Tubular joint 15a: First tubular joint 15b: Second tubular joint 16:Connection part 16a: First magnetic pole part 16b: Second magnetic pole part 17:Connection part 17a: First magnetic pole part 17b: Second magnetic pole part 20: Hub 20a: Connection port 100: Catheter 101: Administration Lumen 101a: Discharge hole 101a1: 1st discharge hole 101a2: 2nd discharge hole 101a3: 3rd discharge hole 101b: Inflow hole 101c: Tip opening A: Long direction A1: Tip A2: Proximal side BV: Blood vessel GW: Guidewire O: Central axis X: administered substance

Claims

1. It comprises a tubular body that has an internally partitioned administration lumen through which the substance to be administered to the living body can flow, The side wall of the tubular body has, A discharge port that communicates with the administration lumen and allows the administered substance to be discharged, At a position toward the proximal end in the longitudinal direction of the tubular body from the discharge hole, an inlet hole is provided which communicates with the administration lumen and allows blood to flow into the administration lumen. A catheter wherein the tip surface of the tubular body is partitioned with a tip opening that allows the blood flowing in from the inlet hole to the administration lumen to flow out.

2. The tubular body is A tubular body and It comprises a discharge pipe section connected to the tip of the tubular body, The administration lumen extends across the tubular body and the discharge pipe section. The aforementioned discharge hole is partitioned in the side wall of the discharge pipe section. The inlet is partitioned in the side wall of the tubular body, The aforementioned tip opening is partitioned on the tip surface of the discharge pipe section, The catheter according to claim 1, wherein the discharge pipe portion is foldable so as to extend along the longitudinal direction of the tubular body.

3. The aforementioned discharge pipe section is The discharge pipe body has a side wall that demarcates the discharge hole, It comprises a tubular joint portion located between the tubular body and the discharge pipe body, and having less bending rigidity than the discharge pipe body, The catheter according to claim 2, wherein the discharge pipe body is foldable so as to extend along the longitudinal direction of the tubular body by bending deformation of the tubular joint portion.

4. The discharge pipe body is made of a porous material. The catheter according to claim 3, wherein the discharge hole is a hole formed in the discharge tube body.

5. When the discharge hole is referred to as the first discharge hole, the discharge pipe body as the first discharge pipe body, and the tubular joint portion as the first tubular joint portion, The aforementioned discharge pipe section is The second discharge pipe body has a second discharge hole partitioned in its side wall, It comprises a second tubular joint portion located between the first discharge pipe body and the second discharge pipe body, and having less bending rigidity than the second discharge pipe body, The catheter according to claim 3 or 4, wherein the second discharge pipe body is foldable so as to extend along the extending direction of the first discharge pipe body by bending deformation of the second tubular joint portion.

6. The first discharge pipe body is foldable from the distal side to the proximal side by the first tubular joint, The catheter according to claim 5, wherein the second discharge tube body is foldable back from the proximal side to the distal side by the second tubular joint.

7. The catheter according to claim 6, wherein the discharge pipe section comprises a third discharge pipe body that connects the tubular body and the first tubular joint section and has a third discharge hole demarcated in its side wall.

8. The catheter according to claim 6, further comprising a guide member whose tip is connected to the second tubular joint and which moves along the tubular body to guide the folding motion of the first discharge pipe body and the second discharge pipe body.

9. The catheter according to claim 5, wherein the first discharge tube body and the second discharge tube body are provided with a connecting portion that can be connected by magnetic force, with the second discharge tube body folded back so as to extend along the extending direction of the first discharge tube body.

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