WO2018021179A1

WO2018021179A1 - Catheter

Info

Publication number: WO2018021179A1
Application number: PCT/JP2017/026457
Authority: WO
Inventors: 秀治狩谷; 昇谷川; 秀和当瀬; 淳関野
Original assignee: 学校法人関西医科大学; 株式会社ハイレックスコーポレーション
Priority date: 2016-07-26
Filing date: 2017-07-21
Publication date: 2018-02-01
Also published as: JP2018015086A; JP6758638B2

Abstract

A catheter 1, into which a stylet wire 2 is inserted, is provided with a body part 11, a distal-end part 12, and a proximal-end part 13, the distal-end part 12 having a small-diameter part 12b and a intermediate-diameter part 12c having a larger diameter than the small-diameter part 12b, the small-diameter part 12b having an inside diameter whereby bending thereof is possible in a state in which an internal peripheral surface thereof lies along an external peripheral surface of the stylet wire 2 when the small-diameter part 12b is bent in a state in which the stylet wire 2 is inserted therein, the intermediate-diameter part 12c having an inside diameter whereby a drug can flow through in a state in which the stylet wire 2 is inserted, and the catheter 1 having a marker M1 provided to the small-diameter part 12b and a proximal-end-side marker M2 provided so that positioning of a distal end 2a of the stylet wire 2 in the intermediate-diameter part 12c is visible.

Description

catheter

The present invention relates to a catheter.

When using the catheter for angiography, insert the catheter into the blood vessel and push it to the target site. Specifically, a guide wire capable of giving an angle shape as shown in Patent Document 1 is inserted from the guide wire introduction opening to the distal end of the catheter body. Extending the tip of the guide wire from the tip of the catheter and turning the guide wire inside the blood vessel while changing the direction of the angled tip in the blood vessel while maintaining the state where the guide wire precedes the catheter Then, the wire is inserted into the target blood vessel by pushing and pulling the wire. When the wire enters the target blood vessel, the wire is held, and the catheter tip is inserted into the target blood vessel by following the wire. To perform this operation, it is necessary for the surgeon to grasp the travel of the blood vessel. Before the catheter is advanced to the target blood vessel, the contrast medium is released from the catheter, X-ray imaging is performed, and a map to the target blood vessel is obtained. Need to get. When the tip of the catheter reaches the target site, the preceding wire is removed, and a contrast agent is injected by an injection device such as a syringe and released from the catheter tip. The contrast medium released into the blood vessel is X-rayed to diagnose the blood vessel morphology and blood flow state. When a map to a new target blood vessel is obtained, the catheter is further advanced to the target blood vessel by the same method, and the final target blood vessel is reached. In this way, angiography is appropriately performed from the central large blood vessel, and branches are selected step by step to reach the final target peripheral blood vessel.

Patent Document 2 discloses a catheter that is reduced in taper so that the inner diameter of the distal end portion of the catheter is narrowed, and that the clearance between the inner periphery of the distal end portion and the outer periphery of the guide wire is reduced to improve the followability of the catheter to the guide wire. Is disclosed.

JP-A-5-220225 JP 2006-149442 A

Conventionally, when a contrast medium is injected by inserting a catheter into a blood vessel, since the guide wire is removed and injected, it is necessary to insert the guide wire again when moving the catheter from which the guide wire has been removed. If the number of times the guide wire is removed and inserted is increased, the risk of blood vessel damage increases, and the operation takes time, putting a burden on the human body.

When attempting to inject without removing the guide wire from the catheter, if the clearance between the catheter tip and the guide wire is small, the amount of contrast medium that can be injected is small and the desired amount of contrast medium cannot be injected. On the other hand, when the clearance between the catheter tip and the guide wire is increased, the followability of the catheter with respect to the guide wire is impaired.

Therefore, the present invention provides a catheter that can inject a desired amount of contrast agent and does not impair the followability of the catheter with respect to the guide wire when an agent such as a contrast agent is to be injected without removing the guide wire from the catheter. The purpose is to do.

The catheter of the present invention is a catheter into which a stylet wire is inserted into a body cavity, and the catheter includes a main body having a lumen, a distal end provided on one end side of the main body, A proximal end portion provided at an end portion of the main body portion opposite to the distal end portion and having a proximal end side opening portion into which the stylet wire can be inserted, and the distal end portion is thinner than the main body portion. A narrow-diameter portion that is a diameter, and a medium-diameter portion that is smaller in diameter than the main body portion and larger in diameter than the thin-diameter portion, and the narrow-diameter portion is smaller than the outer diameter of the stylet wire. The inner diameter portion is provided with a lumen having an inner diameter that can be bent when the stylet wire is bent in a state in which the stylet wire is inserted. With the stylet wire inserted A lumen having an inner diameter capable of flowing through, and having a flexibility capable of bending following the bending of the small-diameter portion by the stylet wire, and the catheter is provided in the small-diameter portion. And a proximal-side marker provided so that it can be visually confirmed that the tip of the stylet wire is positioned at the medium diameter portion.

According to the catheter of the present invention, when a drug is to be injected without removing the stylet wire from the catheter, a desired amount of drug can be injected and the followability of the catheter to the stylet wire is improved.

1 is an overall view showing a medical device using a catheter according to an embodiment of the present invention. (A) is a cross-sectional view of the catheter of FIG. 1 cut along the axial direction before the stylet wire enters the distal end of the catheter, and (B) is the catheter of (A). FIG. (A) is sectional drawing which shows the state in which the stylet wire was inserted in the small diameter part of the catheter in the catheter of FIG. 1, (B) is a tip of a stylet wire retreating to the inside diameter part of a catheter. It is a side view which shows the state which carried out. It is the schematic which shows the state which the catheter of FIG. 1 located in front of the branch location of the blood vessel. It is the schematic which shows the state by which the contrast agent was discharge | released from the catheter of FIG. FIG. 2 is a schematic view showing a state where the distal end portion of the catheter of FIG. 1 is inserted into a blood vessel toward a target site at a branching portion of the blood vessel.

Hereinafter, a catheter according to an embodiment of the present invention will be described with reference to the drawings. In the following embodiment, a medical device including a catheter and a stylet wire will be described as an example. However, the following embodiment is merely an example, and the catheter of the present invention is described in the following embodiment. It is not limited.

1, the medical device D includes a catheter 1 inserted into a body cavity and a stylet wire 2 inserted into the catheter 1. In the present embodiment, the medical device D is an injection that injects a drug into the inside of the catheter 1 as shown in FIG. 1 in order to release a drug such as a contrast medium from the tip of the catheter 1 inserted into the body cavity. A tool 3 is further provided. For example, the medical device D inserts the catheter 1 into a body cavity and discharges the drug from the distal end portion 12 side of the catheter 1, thereby diagnosing or treating a target site in humans or animals and preventing disease. Used. The medical device D is not limited to the structure shown in FIG. 1, and can be applied to any structure used for diagnosis and treatment using the catheter 1.

The catheter 1 is a tube-like member into which the stylet wire 2 is inserted as shown in FIGS. 1, 2 (A) and 2 (B). The catheter 1 is used for performing a predetermined treatment such as introducing a drug into a target site by positioning the distal end portion 12 at a target site in a body cavity such as a blood vessel, a lymphatic vessel, a bile duct, or a digestive tract. The catheter 1 is made of a flexible material so that it can move in a curved body cavity. The material of the catheter 1 is not particularly limited as long as it has flexibility to move along the body cavity, and a synthetic resin or the like used for a known catheter can be used.

The stylet wire 2 is a wire that is inserted into the catheter 1 and functions as the stylet of the catheter 1. The stylet wire 2 moves in the body cavity together with the catheter 1 and is movable with respect to the axial direction of the catheter 1. The stylet wire 2 is composed of an elongated metal wire. As the stylet wire 2, a known guide wire can be used. In the present embodiment, the tip 2a side of the stylet wire 2 is shaped into a curved shape as shown in FIG. Hereinafter, the portion shaped into the curved shape on the distal end 2 a side of the stylet wire 2 is referred to as a distal end region of the stylet wire 2. When the catheter 1 is inserted into the body cavity, the distal end 2a of the stylet wire 2 is positioned on the distal end portion 12 side of the catheter 1 as shown in FIG. The stylet wire 2 has rigidity capable of bending the distal end portion 12 of the catheter 1 along the curvature of the stylet wire 2. Thus, when the distal end 2a of the stylet wire 2 is inserted into the distal end portion 12 of the catheter 1, the distal end portion 12 is deformed along the curved shape of the distal end region of the stylet wire 2 as shown in FIG. The

The other end (not shown) of the stylet wire 2 is led out from a proximal end portion 13 of the catheter 1 which will be described later, and is located on the proximal side so that a hand operation is possible. The material and structure of the stylet wire 2 are not particularly limited. For example, as the material of the stylet wire 2, SUS, Ni—Ti alloy or the like can be used. Examples of the structure of the stylet wire 2 include a single wire or a stranded wire, and a single wire or a stranded wire as a core wire and a single wire or a stranded wire wound around the outer periphery in a coil shape. The distal end region of the stylet wire 2 may be shaped by bending, such as a curve, at the time of manufacture, or may be shaped by the surgeon according to the blood vessel during the operation. An arbitrary shape is provided on the stylet wire 2 and an arbitrary shape is also provided on the distal end of the catheter 1. With this combination, the operator can always change the shape according to the blood vessel shape without removing the catheter 1 into an arbitrary three-dimensional shape. It can also be made possible.

As shown in FIG. 1, the catheter 1 includes a main body portion 11 having a lumen B <b> 1 (see FIG. 2A), a distal end portion 12 provided on one end side of the main body portion 11, and a distal end portion 12. And a base end portion 13 provided at the end of the main body portion 11 on the opposite side. As shown in FIG. 2A, the lumen B1 of the main body 11 communicates with the lumen B2 of the distal end portion 12 and the lumen (not shown) of the proximal end portion 13. Thereby, the stylet wire 2 can be inserted into the catheter 1, and the medicine can be supplied from the proximal end portion 13 side to the distal end portion 12.

The distal end portion 12 is a portion that is formed at the distal end of the catheter 1 and advances in advance in a body cavity such as a blood vessel. As will be described later, the distal end portion 12 bends along the shape of the shaped and curved stylet wire 2 and can be advanced toward the target site at a branch point in a body cavity such as a blood vessel. . Details of the distal end portion 12 will be described later.

The main body 11 is a long part of the catheter 1 located between the distal end 12 and the proximal end 13 as shown in FIG. The main body 11 has a predetermined length necessary for the catheter 1 to reach a target site in the body from the body surface. Moreover, the main-body part 11 has a predetermined | prescribed outer diameter according to a body cavity so that it can insert in body cavities, such as a blood vessel. The outer diameter of the main body 11 is larger than the outer diameter of the distal end portion 12 (a small diameter portion 12b and a medium diameter portion 12c described later). Thereby, the main body 11 has higher rigidity than the distal end portion 12 and also has necessary pushability and torque transmission from the proximal end portion 13 to the distal end portion 12. Further, the main body 11 is configured to be less crushed than the distal end 12 when inserted into the body cavity. The lumen B1 of the main body 11 serves as a supply path for a medicine supplied from the proximal end 13 side while the stylet wire 2 is inserted. In the present embodiment, the inner diameter of the lumen B1 of the main body portion 11 is larger than the inner diameter of the lumen B2 of the distal end portion 12. Thereby, the medicine can be smoothly supplied when the medicine passes through the main body 11. The inner diameter of the lumen B1 is not particularly limited as long as the stylet wire 2 can be inserted and the medicine can be smoothly supplied.

The proximal end portion 13 is a portion where various operations for diagnosis and treatment of the target portion using the catheter 1 such as insertion of the stylet wire 2 are performed. As shown in FIG. 1, the base end portion 13 has a base end side opening 13 a into which the stylet wire 2 can be inserted. Moreover, the base end part 13 has the main-body-part side opening part 13b in the main-body part 11 side. The proximal end side opening portion 13a and the main body portion side opening portion 13b communicate with each other through a lumen (not shown) of the proximal end portion 13, and the main body portion side opening portion 13b communicates with the lumen B1 of the main body portion 11. ing. Thereby, the stylet wire 2 inserted from the proximal end side opening 13a passes through the lumen of the proximal end portion 13, the lumen B1 of the main body portion 11, the lumen B2 of the distal end portion 12, and the The tip of the stylet wire 2 can be projected and retracted from the tip side opening 12a (see FIG. 2A).

The structure of the proximal end portion 13 is not particularly limited as long as the stylet wire 2 can be inserted. In the present embodiment, the proximal end portion 13 is shown as a catheter hub connected to the main body portion 11 as shown in FIG. Yes. More specifically, the base end portion 13 is shown as a Y-shaped connector that is bifurcated in the present embodiment. As shown in FIG. 1, the base end portion 13 includes a wire insertion portion 13 c into which the stylet wire 2 is inserted and an injection device connection portion 13 d to which the injection device 3 is connected. In the present embodiment, the injection device 3 is directly connected to the injection device connection portion 13d. However, the injection device 3 may be connected indirectly through another member such as a connector (not shown). The wire insertion portion 13c and the injection tool connection portion 13d are connected to a base portion 13e connected to the main body portion 11 of the catheter 1. The wire insertion portion 13c and the base portion 13e are formed hollow and communicate with each other so that the stylet wire 2 inserted into the wire insertion portion 13c can be introduced into the lumen B1 of the main body portion 11. In addition, the injection tool connecting portion 13d and the base portion 13e are formed in a hollow shape and communicate with each other so that a drug can be supplied from the injection tool 3 to the catheter 1. In the present embodiment, the base portion 13e and the injection tool connection portion 13d are provided in a straight line, and the wire insertion portion 13c is provided inclined with respect to the base portion 13e and the injection tool connection portion 13d. However, the arrangement and shape of each part of the base end part 13 are not limited to those illustrated.

Further, as shown in FIG. 1, the wire insertion portion 13c may include a backflow prevention valve 13f that prevents the medicine injected from the injection tool 3 from flowing back to the proximal end opening portion 13a. While the stylet wire 2 can be inserted, the backflow prevention valve 13f includes a slit, a switch, a cock, and the like so as to prevent the medicine from leaking out from the proximal opening 13a when the medicine is injected. It only has to be. Further, in order to facilitate rotation of the stylet wire 2 around the axis and facilitate transmission of torque to the distal end side of the catheter 1, a torque device 13g (see FIG. 1) is provided on the proximal side of the stylet wire 2. It may be provided. A known torque device can be used as the torque device 13g, but the torque device 13g may be fixed to the proximal end portion 13 in order to restrict relative movement between the stylet wire 2 and the catheter 1 in the axial direction. Good. For example, a connecting portion that can be attached to and detached from the base end portion 13 is provided in the torque device 13g, a connected member including the backflow prevention valve 13f is provided at the free end of the wire insertion portion 13c, and the connecting portion of the torque device 13g is connected to the connected member. You may connect to.

The injection tool 3 connected to the injection tool connection portion 13d is a member that injects a drug into the catheter 1. The drug injected from the injection device 3 into the catheter 1 is a substance released into the body cavity for the purpose of treatment, examination, disease prevention, and the like. The drug is not particularly limited as long as it is a drug for the purpose of treatment or examination, disease prevention, or the like, for example, a contrast agent, an anticancer agent, or a thrombolytic agent. In the present embodiment, a contrast medium is described as an example, but the drug injected from the injection tool 3 may be other than the contrast medium. A contrast agent is administered to a patient in order to make an image while contrasting an image or emphasizing a specific tissue during image diagnosis using X-rays. For example, when the catheter 1 travels through a body cavity such as a blood vessel, the contrast agent is released from the distal end portion 12 of the catheter 1 into the body cavity. The contrast medium is released and the body cavity in the vicinity of the distal end portion 12 of the catheter 1 is X-rayed, so that a contrast image of a body cavity such as a blood vessel can be displayed on an image display device (not shown). In this embodiment, as shown in FIG. 1, a syringe is used as the injection tool 3, but the injection tool 3 is not limited to a syringe as long as a drug can be injected into the catheter 1. For example, as an infusion device, an infusion bag may be used, or a medicine supply device including an infusion mechanism such as a pump may be used.

Next, the distal end portion 12 of the catheter 1 will be described with reference to FIGS. 1 to 3B. The distal end portion 12 is configured to bend at the distal end of the catheter 1 following the curvature of the distal end region of the stylet wire 2. As a result, by operating the catheter 1, it is easy to advance the distal end portion 12 in a direction toward the target site at a branch point of a body cavity such as a blood vessel. Although details will be described later, the distal end portion 12 can release the contrast agent from the distal end side opening portion 12a (see FIG. 2A) without removing the stylet wire 2 from the catheter 1.

As shown in FIGS. 2A and 2B, the distal end portion 12 has a narrow diameter portion 12b that is smaller in diameter than the main body portion 11, and a smaller diameter than the main body portion 11 and is smaller than the small diameter portion 12b. And a medium diameter portion 12c having a large diameter. The small diameter portion 12 b is located on the distal end side of the distal end portion 12, and the middle diameter portion 12 c is provided on the proximal end side (the main body portion 11 side) of the small diameter portion 12 b in the distal end portion 12.

The small diameter portion 12b is provided on the distal end side of the distal end portion 12 relative to the middle diameter portion 12c, and is a portion that becomes the leading side when the catheter 1 advances in the body cavity. In the small diameter portion 12b, the stylet wire 2 is inserted at least partially when the catheter 1 advances in the body cavity. As shown in FIG. 1 and FIG. 3A, the small diameter portion 12b is deformed along the curvature of the distal end region of the stylet wire 2. In the present embodiment, as shown in FIG. 2A, the small-diameter portion 12b has a distal end side opening 12a at the distal end (the free end of the distal end portion 12), and contrast is formed from the distal end side opening 12a. The agent can be released.

As shown in FIGS. 2A and 2B, the outer diameter of the small diameter portion 12b is smaller than the outer diameter of the main body portion 11 and the medium diameter portion 12c. As a result, when the catheter 1 is advanced toward the target site at a branch point of a body cavity such as a blood vessel, the tip of the small diameter portion 12b is caught on the surface of the body cavity such as a blood vessel wall (see reference numeral VW in FIG. 5). It is difficult to damage the surface of the body cavity. The outer diameter of the small-diameter portion 12b is not particularly limited as long as the small-diameter portion 12b is easily inserted into the target site at a branch point in the body cavity. The small diameter portion 12b is deformed along the curvature of the distal end region of the stylet wire 2 so as to facilitate insertion of the catheter 1 toward the target site at a branch point in the body cavity or the like. It has a length. The axial length of the small-diameter portion 12b can be appropriately changed according to the length of the distal end region of the stylet wire 2, and is not particularly limited. Moreover, the shape of the small diameter part 12b is not specifically limited, For example, it can be set as a substantially cylindrical shape.

As shown in FIG. 2A, the small diameter portion 12b has a lumen B21 having an inner diameter larger than the outer diameter of the stylet wire 2. As shown in FIG. 3A, the inner diameter of the lumen B21 is such that the inner peripheral surface IS of the small diameter portion 12b is a stylet when the small diameter portion 12b is bent with the stylet wire 2 inserted. The size of the wire 2 is such that it can be bent along the outer peripheral surface OS. That is, when the stylet wire 2 is inserted into the narrow diameter portion 12b, the small diameter portion 12b follows the curvature of the distal end region of the stylet wire 2 and is in substantially the same curved state. Therefore, since the small-diameter portion 12b having a small outer diameter follows the curvature of the distal end region of the stylet wire 2, the catheter 1 and the stylet wire 2 are both moved from the branching point in the body cavity toward the target site. You can move forward. Therefore, unlike the prior art, a complicated and time-consuming operation of advancing only the guide wire and then advancing the catheter is unnecessary, and the treatment time can be shortened.

The inner diameter of the lumen B21 of the small diameter portion 12b is not particularly limited as long as the inner peripheral surface IS of the small diameter portion 12b can be bent in a state along the outer peripheral surface OS of the stylet wire 2, for example. As long as 2 can be inserted, the outer diameter of the stylet wire 2 can be made substantially the same. As shown in FIG. 3 (A), the lumen B21 of the small-diameter portion 12b can form a gap with which the body fluid can flow with the outer surface OS of the stylet wire 2 in a state where the stylet wire 2 is inserted. Also good. In this case, bodily fluids such as blood can flow through the gap between the inner circumferential surface IS of the narrow-diameter portion 12b and the outer circumferential surface OS of the stylet wire 2, and air remaining in the gap or a medical solution such as a contrast medium can be removed. It becomes easy to discharge to the outside of the catheter 1. Further, with the stylet wire 2 inserted, a small amount of a medical solution such as a contrast medium may be discharged through the gap from the distal end side opening 12a of the small diameter portion 12b into the body cavity.

The middle diameter portion 12c is a portion provided on the proximal end side of the small diameter portion 12b that constitutes the distal end portion 12 of the catheter 1 together with the small diameter portion 12b. The medium diameter portion 12c has flexibility that allows bending following the bending of the small diameter portion 12b by the stylet wire 2. Since the middle diameter portion 12 c exists between the distal end portion 12 and the main body portion 11 of the catheter 1, a step between the main body portion 11 and a portion having a smaller diameter than the main body portion 11 can be reduced. Can bend more along the stylet wire 2. Therefore, as shown in FIG. 3A, the medium diameter portion 12c can be bent on the proximal end side of the distal end portion 12 of the catheter 1 when the stylet wire 2 is inserted into the small diameter portion 12b. . The medium diameter portion 12c is not only curved following the bending of the small diameter portion 12b by the stylet wire 2, but the tip 2a of the stylet wire 2 has a medium diameter as shown in FIG. When located in the part 12c, it may be bent directly by the stylet wire 2. Further, the shape of the middle diameter portion 12c is not particularly limited, but may be substantially cylindrical as shown in FIGS. 2A and 2B, for example.

As shown in FIGS. 2A and 2B, the outer diameter of the medium diameter portion 12c is smaller than the outer diameter of the main body portion 11 and larger than the outer diameter of the small diameter portion 12b. Yes. This facilitates insertion of the catheter 1 into a body cavity such as a blood vessel toward the target site when the catheter 1 is advanced toward the target site at a branch point of the body cavity such as a blood vessel. The outer diameter of the medium diameter portion 12c is not particularly limited as long as it is smaller than the outer diameter of the main body portion 11 and larger than the outer diameter of the small diameter portion 12b. Further, the axial length of the medium diameter portion 12c is not particularly limited as long as it can be bent along the distal end region of the stylet wire 2 together with the small diameter portion 12b.

The distal end 2a of the stylet wire 2 protrudes from the small-diameter portion 12b shown in FIG. 3A when releasing the contrast agent at, for example, a branch point in the body cavity, or the lumen of the small-diameter portion 12b. From the position in B21, it is positioned in the lumen B22 of the medium diameter portion 12c shown in FIG. The medium diameter portion 12c is provided with a lumen B22 (see FIGS. 2A and 3A) having an inner diameter that allows the contrast medium to flow in a state where the stylet wire 2 is inserted. The medium diameter portion 12c is a state in which the stylet wire 2 is inserted into the lumen B22 of the medium diameter portion 12c (see FIGS. 3A and 3B). The supply path which can be supplied toward is formed. In the present embodiment, as shown in FIG. 2A, the lumen B22 of the medium diameter portion 12c is formed to be at least larger than the inner diameter of the lumen B21 of the small diameter portion 12b. The inner diameter of the lumen B22 of the medium diameter portion 12c is not particularly limited as long as a gap is formed between the outer circumference of the stylet wire 2 and the inner wall of the medium diameter portion 12c and the contrast medium can be circulated in the gap. Note that the inner diameter of the medium diameter portion 12c can be appropriately set according to the use situation such as the type of medicine and the purpose and size of the catheter, as long as the effects of the present invention can be exhibited.

In this embodiment, as described above, the medium diameter portion 12c is deformed according to the curvature of the distal end region of the stylet wire 2, and the contrast medium can be circulated in the state where the stylet wire 2 is inserted. In this case, when supplying the contrast agent, as shown in FIG. 3B, the middle diameter portion 12c is bent by the distal end region of the stylet wire 2, and the distal end portion 12 of the catheter 1 is bent. . Therefore, even when the distal end 2a of the stylet wire 2 does not protrude from the small-diameter portion 12b (or when it is not in the lumen B21 of the small-diameter portion 12b), the small-diameter portion 12b is released when the contrast agent is released. The front opening 12a can be oriented. Therefore, it becomes easy to release the contrast agent in a desired direction.

In this embodiment, as shown in FIGS. 2 (A) and 2 (B), a reduced diameter portion (in which the inner diameter and the outer diameter decrease toward the tip) between the small diameter portion 12b and the medium diameter portion 12c ( (Hereinafter referred to as a tip-side reduced diameter portion) 12d. In the present embodiment, the tip-side reduced diameter portion 12d is reduced in diameter as both the inner diameter and the outer diameter are directed toward the tip, but the tip-side reduced diameter portion 12d is only one of the inner diameter and the outer diameter. May have a reduced diameter. When the inner diameter of the distal-side reduced diameter portion 12d is reduced, the contrast agent can be smoothly supplied from the medium diameter portion 12c side to the small diameter portion 12b side. In addition, when the outer diameter of the distal-side reduced diameter portion 12d is reduced, the catheter 1 can be easily inserted into the body cavity toward the target site at a branching site in the body cavity such as a blood vessel.

Further, in the present embodiment, there is a reduced diameter portion (hereinafter referred to as a proximal-side reduced diameter portion) 12e that is reduced in diameter as the inner diameter and the outer diameter toward the distal end between the middle diameter portion 12c and the main body portion 11. ing. In the present embodiment, the proximal-side reduced diameter portion 12e is reduced in diameter as both the inner diameter and the outer diameter are directed toward the distal end. However, the proximal-side reduced diameter portion 12e is any of the inner diameter and the outer diameter. Only one of the diameters may be reduced. When the inner diameter of the proximal-side reduced diameter portion 12e is reduced, the contrast agent can be smoothly supplied from the main body portion 11 side to the intermediate diameter portion 12c side. Further, when the outer diameter of the proximal-side reduced-diameter portion 12e is reduced, the catheter 1 can be easily inserted into the body cavity toward the target site at a branch point in the body cavity such as a blood vessel.

As shown in FIGS. 2 (B) and 3 (B), the catheter 1 has a marker M1 provided on the small diameter portion 12b (hereinafter referred to as a small diameter portion side marker) M1 and a stylus on the medium diameter portion 12c. The proximal end side marker M2 provided so that it can visually recognize that the front-end | tip 2a of the let wire 2 is located is provided.

The small diameter portion side marker M1 is a marker for grasping the positional relationship between the distal end 2a of the stylet wire 2 and the small diameter portion 12b of the catheter 1 and the position of the distal end of the catheter 1. More specifically, the positional relationship between the wire-side marker M3 and the small-diameter portion-side marker M1 provided on the stylet wire 2 is grasped on the image display device under X-ray fluoroscopy. When the catheter 1 in which the distal end portion 12 is bent by the stylet wire 2 is advanced in the body cavity, the distal end of the stylet wire 2 from the distal end side opening portion 12a of the small diameter portion 12b by the small diameter portion side marker M1. The state in which 2a protrudes and the state in which the tip 2a of the stylet wire 2 enters the lumen B21 of the small diameter portion 12b can be easily confirmed. In the present embodiment, the wire-side marker M3 is provided on the distal end 2a side of the stylet wire 2. However, the position at which the wire side marker M3 is provided is not particularly limited as long as the positional relationship with the small diameter portion side marker M1 and the proximal end side marker M2 can be grasped.

In this embodiment, the small-diameter portion side marker M1 is provided at the tip of the small-diameter portion 12b as shown in FIGS. 2 (B) and 3 (B). In this case, the position of the tip of the small diameter portion 12b can be easily grasped, and the positional relationship between the tip 2a of the stylet wire 2 and the tip of the small diameter portion 12b can be easily grasped. The position where the small-diameter portion side marker M1 is provided is not particularly limited as long as it can be grasped that the tip 2a of the stylet wire 2 is at a predetermined position, such as a position where the tip 2a of the stylet wire 2 protrudes.

The proximal end side marker M2 is a marker for grasping the positional relationship between the distal end 2a of the stylet wire 2 and the medium diameter portion 12c. More specifically, the wire side marker M3 and the proximal end side marker M2 are visually recognized on the image display device under X-ray fluoroscopy so as to grasp the mutual positional relationship. When the contrast agent is released from the distal opening 12a of the catheter 1, it can be confirmed by the proximal marker M2 that the distal end 2a of the stylet wire 2 is located in the lumen B22 of the medium diameter portion 12c. . The proximal end marker M2 may be a marker that can adjust the positional relationship with the stylet wire 2.

In the present embodiment, one proximal-side marker M2 is provided on each of the distal end side and the proximal end side of the middle diameter portion 12c as shown in FIGS. 2B and 3B ( Hereinafter, the distal marker is referred to as a first proximal marker M21, and the proximal marker is referred to as a second proximal marker M22). In this case, when the distal end 2a of the stylet wire 2 is positioned on the middle diameter portion 12c when the contrast agent is released, the first proximal end marker M21 and the second proximal end marker M22 are used as marks to identify the wire side marker M3. The position can be adjusted. Therefore, it is possible to easily adjust the position of the stylet wire 2 in the axial direction that requires high accuracy with respect to the catheter 1. In addition, by grasping the positional relationship between the small-diameter portion side marker M1, the first proximal end side marker M21 and the second proximal end side marker M22, the bending state of the distal end portion 12 of the catheter 1 within the body cavity, the catheter It is possible to easily grasp how one tip portion 12 is oriented. The position where the proximal end side marker M2 is provided is not particularly limited as long as it can be understood that the distal end 2a of the stylet wire 2 is located in the lumen B22 of the medium diameter portion 12c. For example, the proximal end side marker M2 may be provided in addition to the middle diameter portion 12c.

In addition, the number, width, and position in the axial direction of the above-described small-diameter portion side marker M1, proximal end side marker M2, and wire side marker M3 are not particularly limited. In the present embodiment, the small-diameter portion side marker M1, the proximal end side marker M2, and the wire side marker M3 are formed as annular lines. However, any shape and pattern of the marker can be used as long as they are visible. It can be a shape or a pattern.

As described above, when the catheter 1 is moved, the catheter 1 can move integrally with the stylet wire 2 inserted into the small diameter portion 12b, and the body cavity branches. Is easily inserted into the body cavity toward the target site, and the body cavity is not easily damaged. When the contrast agent needs to be released, the tip 2a of the stylet wire 2 only needs to be moved slightly from the small diameter portion 12b side to the medium diameter portion 12c side. Therefore, when releasing the contrast agent, the operation of removing the stylet wire 2 from the catheter 1 is unnecessary, and when the catheter 1 is advanced again, the operation of reinserting the stylet wire 2 is also unnecessary. After the contrast agent is released, the catheter 1 can be quickly moved to the target site by slightly moving the stylet wire 2 from the medium diameter portion 12c to the small diameter portion 12b. Since the small-diameter portion side marker M1 and the proximal end side marker M2 are provided, it is easy to grasp the positional relationship of the stylet wire 2 or the catheter 1 with respect to each other and adjust the operation amount when the contrast agent is released. Become. Therefore, the procedure at the time of releasing the contrast agent can be performed easily and quickly, the procedure time in the body cavity can be shortened, and the burden on the patient is reduced.

In addition, when the distal end 2a of the stylet wire 2 is positioned at the middle diameter portion 12c when the contrast agent is released, the middle diameter portion 12c is curved following the curvature of the stylet wire 2. Therefore, the curvature of the distal end portion 12 of the catheter 1 is maintained even when the contrast agent is released (see FIG. 3B). Therefore, it becomes easy to orient the distal end portion 12 of the catheter 1 when releasing the contrast agent and to release the contrast agent in a desired direction.

Next, an example of the operation of the catheter 1 and the medical device D of this embodiment will be described. In addition, the following description is an example to the last, does not limit this invention, and may be used with another operation method.

First, as shown in FIG. 4, the stylet wire 2 is inserted into the catheter 1, and the distal end 2 a of the stylet wire 2 is projected from the distal end side opening portion 12 a of the small diameter portion 12 b of the catheter 1. The small diameter portion 12b of the catheter 1 is curved along the curvature of the distal end region of the stylet wire 2, and the middle diameter portion 12c is curved following the curvature of the small diameter portion 12b.

The catheter 1 is inserted into the body cavity, and the catheter 1 moves forward in the blood vessel Va together with the stylet wire 2. Note that while the stylet wire 2 is inserted into the small diameter portion 12b while the catheter 1 is advanced in the blood vessel Va, the inner peripheral surface IS of the small diameter portion 12b and the outer peripheral surface OS of the stylet wire 2 are A small amount of contrast agent may be released from the gap (see FIG. 3A). When the distal end portion 12 of the catheter 1 reaches the branching point of the blood vessel Va as shown in FIG. 4, the small-diameter portion side marker M1, the first proximal side marker M21, and the second base portion displayed on the image display device. By grasping the positional relationship of the end side marker M22, the direction of the distal end of the catheter 1 is adjusted.

In order to release the contrast agent at the branching point of the blood vessel Va, as shown in FIG. 5, the stylet wire 2 is retracted with respect to the distal end of the catheter 1, and the distal end 2a of the stylet wire 2 is moved to the middle diameter portion 12c. To move. Thereby, the stylet wire 2 is extracted from the lumen B21 of the small-diameter portion 12b. By operating the injection tool 3 (see FIG. 1), the contrast medium is supplied from the proximal end portion 13 of the catheter 1 to the lumen B1 of the main body portion 11, the lumen B22 of the medium diameter portion 12c, and the lumen B21 of the small diameter portion 12b. Then, the contrast medium is released from the distal end side opening 12a. Since the contrast medium can be circulated in the lumen B22 of the middle diameter portion 12c with the stylet wire 2 inserted, the contrast medium can be smoothly discharged. When the contrast agent needs to be released, the above operation is performed each time, so that the contrast agent can be released with a simple operation without removing the stylet wire 2 from the catheter 1 each time the contrast agent is released. Therefore, there is no need to extract the stylet wire 2 or insert it again before and after the release of the contrast agent, and the time for the procedure can be shortened. Therefore, the burden on the patient due to the long-time treatment is reduced.

As shown in FIG. 5, when the blood vessel Vb toward the target site is imaged at the branching point of the blood vessel Va, the catheter 1 is moved toward the blood vessel Vb toward the target site. At this time, as shown in FIG. 6, the distal end 2a of the stylet wire 2 is projected from the distal end portion 12 of the catheter 1 while recognizing the positional relationship between the small-diameter portion side marker M1 and the wire side marker M3 again. . With the narrow diameter portion 12b bent along the curvature of the distal end region of the stylet wire 2, the narrow diameter portion 12b of the catheter 1 is inserted into the entrance of the blood vessel Vb toward the target site, as shown in FIG. , Move forward. At this time, since the distal end of the catheter 1 has a small diameter due to the small diameter portion 12b, it is easy to insert the distal end of the catheter 1 into the blood vessel Vb. For this reason, the blood vessel wall VW around the entrance of the blood vessel Vb toward the target site is hardly damaged by the distal end of the catheter 1. When the above operation is repeated and the distal end of the catheter 1 reaches the target site, predetermined treatments such as drug release and blood suction are performed, and examinations and treatments are performed.

DESCRIPTION OF SYMBOLS 1 Catheter 11 Main body part 12 Tip part 12a Tip side opening part 12b Thin diameter part 12c Medium diameter part 12d Tip side diameter reduction part 12e Base end side diameter reduction part 13 Base end part 13a Base end side opening part 13b Main body part side opening part 13c Wire insertion part 13d Injection tool connection part 13e Base part 13f Backflow prevention valve 13g Torque device 2 Stylet wire 2a Stylet wire tip 3 Injection tool B1 Body part lumen B2 Tip part lumen B21 Small diameter part lumen B22 Inner diameter lumen D Medical device M1 Small diameter side marker M2 Base end side marker M21 First base end side marker M22 Second base end side marker M3 Wire side marker IS Small diameter part inner peripheral surface OS style Outer surface of let wire Va, Vb Blood vessel VW Blood vessel wall

Claims

A catheter that is inserted into a body cavity and into which a stylet wire is inserted,
The catheter is provided at a body portion having a lumen, a tip portion provided on one end side of the body portion, and an end portion of the body portion opposite to the tip portion, and the stylet wire is inserted therein A proximal end having a possible proximal opening,
The distal end portion has a narrow diameter portion that is smaller in diameter than the main body portion, and a medium diameter portion that is smaller in diameter than the main body portion and larger in diameter than the narrow diameter portion,
The small-diameter portion is larger than the outer diameter of the stylet wire, and can be bent with the inner peripheral surface being along the outer peripheral surface of the stylet wire when the stylet wire is bent and inserted. A lumen having an inner diameter is provided,
The medium diameter portion is provided with a lumen having an inner diameter that allows a medicine to flow in a state where the stylet wire is inserted, and can be bent following the bending of the small diameter portion by the stylet wire. Has flexibility,
The catheter includes
The catheter which has the marker provided in the said small diameter part, and the base end side marker provided so that it could visually recognize that the front-end | tip of the said stylet wire is located in the said medium diameter part.
The catheter according to claim 1, further comprising a reduced-diameter portion between the narrow-diameter portion and the medium-diameter portion, the inner-diameter and outer-diameter being reduced in diameter toward the tip.
The catheter according to claim 1 or 2, wherein the lumen of the small-diameter portion can form a gap through which the body fluid can flow with the stylet wire inserted, from the outer periphery of the stylet wire.