Medical devices

Abstract

To provide a medical device with excellent insertability and operability. [Solution] The medical device 1 comprises a long tubular member 10 that is flexible and has a wire insertion passage formed along its axial direction, and a first operating wire W1 and a second operating wire W2 (operating wire) that are inserted through the wire insertion passage and attached to the distal end 10a of the tubular member 10. The tubular member 10 is integrally composed of a soft portion 12 that bends when pulled by the first operating wire W1 and the second operating wire W2, and a first rigid portion 11 and a second rigid portion 13 that are difficult to bend when operated by the operating wire. The soft portion 12 is located distal to the first rigid portion 11, and the second rigid portion 13 is located distal to the soft portion 12.

Description

Technical Field

[0001] The present invention relates to a medical device that includes an elongated tubular member to be inserted into a living body and is capable of performing a deflection operation on the distal end portion thereof.

Background Art

[0002] Some medical devices such as flexible endoscopes and catheters to be inserted into a living body are provided with an elongated tubular member that is inserted to a target site through a luminal organ or blood vessel in the living body. Among such medical devices, a tip-movable medical device is known in which a movable portion is provided at the distal end of the tubular member, and the movable portion is deflected by pulling an operation wire with an operation device.

[0003] Patent Document 1 below discloses a movable catheter including a first tube portion whose flexibility does not change, and a second tube portion joined to be continuous with the distal end of the first tube portion, the second tube portion being composed of a porous tube that becomes hard according to the degree of compressive force acting in the axial direction and returns to a soft state when the compressive force is released. The movable catheter of Patent Document 1 is provided with a tubular member (sheath) composed of the first tube portion (sheath main body portion) arranged on the proximal end side and the second tube portion (movable portion) arranged on the distal end side, and is configured such that the deflection operation of the movable portion can be performed by pulling the operation wire with the operation device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Conventional medical devices with movable tips have a movable part at the distal end, including the distal end of a long tubular member, which allows for flexible deflection of the distal end's orientation, resulting in excellent insertability into tubular organs and blood vessels. However, for example, in dilated areas (wide spaces) or bifurcations of tubular organs and blood vessels, if the desired position for the distal end is far away, it may not be possible to reach that position, making it difficult to smoothly and appropriately advance the distal end.

[0006] Figure 8 is a diagram illustrating the problems of the present invention. Figure 8 schematically shows the ascending aorta 301, the aortic arch 302, the descending aorta 303, and blood vessels branching from the aortic arch 302. Figure 8 schematically shows a conventional medical device 200, used as a cardiological guiding catheter, inserted into the aortic arch 302. The tubular member 210 of the conventional medical device 200 shown in Figure 8 has a movable part 220 within a predetermined range from its distal end 210a, allowing the orientation of the distal end 210a to be deflected. For example, when attempting to insert the tubular member 210, which has reached the aortic arch 302 from the brachiocephalic artery 311, into the left common carotid artery 312 or the left subclavian artery 313, the distal end 210a of the tubular member 210 may not reach the left common carotid artery 312 or the left subclavian artery 313, making insertion and progression into the target pathway difficult.

[0007] This invention has been made in view of the above-mentioned problems, and aims to provide a medical device with excellent insertability and operability. [Means for solving the problem]

[0008] To achieve the above objective, the medical device according to the present invention comprises a long tubular member having a wire insertion passage formed along the axial direction, and an operating wire inserted through the wire insertion passage and attached to the distal end of the tubular member, wherein the tubular member is integrally composed of a soft portion that bends when the operating wire is pulled, and a first rigid portion and a second rigid portion that are difficult to bend when the operating wire is pulled, wherein the soft portion is located distal to the first rigid portion, and the second rigid portion is located distal to the soft portion.

[0009] According to the above configuration, a second rigid section, which is less likely to bend under traction by the manipulating wire, is provided distal to the soft section, which is the movable part of the tubular member. Therefore, even if the desired position for advancing the distal end of the tubular member is far away, the second rigid section can reach it, allowing the distal end to advance smoothly and appropriately. Furthermore, since the tubular member is integrally constructed in the order of first rigid section, soft section, and second rigid section from the proximal side, a medical device with excellent stability and strength, as well as excellent bending mobility of the movable part, can be realized. In addition, by appropriately setting the axial length of the second rigid section, the position of the movable part can be flexibly adjusted according to the case and procedure. Moreover, by placing the second rigid section at the distal end, including the distal end of the tubular member, the distal end can be made rigid, which improves the mounting stability of the tip to the distal end.

[0010] The medical device according to the present invention has a transition portion disposed between the soft portion and at least one of the first rigid portion and the second rigid portion, and the transition portion may smoothly change the structure of the soft portion and the structure of at least one of the first rigid portion and the second rigid portion in the axial direction.

[0011] According to the above configuration, the structure between the soft and rigid parts changes continuously at the transition section, making it possible to achieve both strength stability and flexibility of the movable part.

[0012] The medical device according to the present invention may have a tubular member having a smooth circumferential surface in the axial direction.

[0013] The above configuration reduces the resistance to insertion into the body and the frictional resistance during the pulling operation of the operating wire, thereby improving the insertability and operability of the medical device.

[0014] In the medical device according to the present invention, the axial length of the first rigid portion may be 90% or more of the total length of the tubular member.

[0015] According to the above configuration, a medical device can be realized in which the majority of the proximal side of the tubular member consists of a first rigid part, and a soft part and a second rigid part are arranged at the distal end as movable parts.

[0016] The medical device according to the present invention may have a tubular member made of polytetrafluoroethylene, and the soft portion may be porous.

[0017] According to the above configuration, it is possible to achieve a soft part with excellent flexibility and suppleness through porous construction, while also possessing excellent biocompatibility and chemical resistance. [Brief explanation of the drawing]

[0018] [Figure 1] This is a plan view showing the overall configuration of a medical device in an embodiment of the present invention. [Figure 2] This is a cross-sectional view along line AA in Figure 1. [Figure 3] This figure shows the vicinity of the distal end of a tubular member in an embodiment of the present invention, where (a) is a schematic perspective view showing the vicinity of the distal end of the tubular member, and (b) is a transmission view for explaining the inside of the tubular member. [Figure 4] This is a plan view illustrating the configuration of a tubular member of a medical device in an embodiment of the present invention. [Figure 5] This figure illustrates the bending motion of the movable part of the tubular member in an embodiment of the present invention, and is a schematic plan view showing the distal end of the tubular member. [Figure 6]This is a diagram showing a state in which the tubular member of the medical device according to the embodiment of the present invention is inserted into a living body. [Figure 7] This is a diagram for explaining the mounting stability of the distal tip to the distal end of the tubular member in the embodiment of the present invention, where (a) is a plan view showing the vicinity of the distal end of the tubular member of the medical device according to the prior art, and (b) is a plan view showing the vicinity of the distal end of the tubular member of the medical device according to the embodiment of the present invention. [Figure 8] This is a diagram for explaining the problem to be solved by the present invention. [Mode for Carrying Out the Invention]

[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification, with reference to the user (operator) of the medical device, the inner side of the patient's body is defined as the distal side, and the user's hand side is defined as the proximal side. The drawings referred to in the present specification do not necessarily have an exact scale relative to the actual dimensions, and some parts are exaggerated or simplified to schematically show the configuration according to the present invention.

[0020] The type of the medical device according to the present invention is not particularly limited, and can be applied to various devices such as flexible endoscopes, catheters, and cannulas. In addition, the use of the medical device according to the present invention is not particularly limited, and it can be used for various medical applications such as treatment and examination in blood vessels such as the aorta or in luminal organs such as the bile duct and pancreatic duct, or guidance of other medical devices to a target site. Hereinafter, a guiding catheter for circulatory organs will be described as an example of the medical device according to the present invention, but the present invention is not limited to the guiding catheter for circulatory organs.

[0021] First, the overall configuration of the medical device 1 according to the embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a plan view showing the overall configuration of the medical device 1 in the present embodiment.

[0022] The medical device 1 shown in Figure 1 comprises a long tubular member 10, and is configured so that a movable part 20 located at the distal end of the tubular member 10 can be bent by an operating device 100. The medical device 1 comprises a tubular member 10 with a movable part 20 at its distal end, an operating device 100, and a first operating wire W1 and a second operating wire W2. As an example, the medical device 1 shown in Figure 1 is configured to bend the movable part 20 in two directions by pulling a pair of first operating wires W1 and second operating wires W2. However, the number of bending directions is not limited to two, and the movable part 20 may be configured to bend in one direction or in three or more directions. In this case, a number of operating wires corresponding to the number of bending directions can be provided, and by pulling each operating wire, the movable part 20 can be bent in the direction of the pulled operating wire, thereby deflecting the tubular member 10.

[0023] The operating device 100 of the medical device 1 shown in Figure 1 is capable of receiving various medical devices. These medical devices can be connected, for example, to the proximal end of the operating device 100. The medical devices connected to the operating device 100 are not particularly limited, nor are there any particular limitations on the method of connecting the medical devices to the operating device 100.

[0024] The tubular member 10 is composed of a long, flexible tube. The tubular member 10 has a movable part 20 at its distal end (left side in Figure 1) that is inserted into the body, which can be bent in the left-right direction. The axial length of the tubular member 10 is not particularly limited and can be set to an appropriate length depending on the application site and use. For example, the tubular member 10 of a medical device 1 used for insertion into the circulatory system is set to a total length of approximately 800 to 1000 mm, and the tubular member 10 of a medical device 1 used for insertion into the digestive system is set to a total length of approximately 2000 to 2500 mm. The radial length (outer diameter) of the tubular member 10 is also not particularly limited and can be set to a length that can be inserted into a tubular organ or blood vessel, or into the instrument insertion channel of a flexible endoscope.

[0025] The material of the tubular member 10 is preferably a flexible material that can be flexibly deformed when inserted into the body, and is also preferably a material that is harmless to the human body. As the material of the tubular member 10, for example, a biocompatible polymer material such as polyurethane, polyethylene, polypropylene, or fluororesin such as polytetrafluoroethylene can be used, and in particular, it is preferable to use polytetrafluoroethylene, which has excellent properties such as chemical resistance, heat resistance, weather resistance, abrasion resistance, and water repellency.

[0026] The tubular member 10 has a tubular structure in which one or more lumens are formed along its extending direction. In this embodiment, the tubular member 10 has a multi-lumen structure. Each lumen opens at the distal end 10a and the proximal end 10b of the tubular member 10 and is independent of each other and does not communicate with one another.

[0027] A tip 50 is attached to the distal end 10a of the tubular member 10, and a movable part 20 is provided proximal to the tip 50, which can be bent by the user using an operating device 100. In this specification, bending includes the concept of curvature that bends like an arc. The axial length and position of the movable part 20 can be appropriately set according to the target site for treatment or examination inside the body.

[0028] The movable part 20, positioned near the distal end 10a of the tubular member 10, has higher flexibility and bending mobility compared to the parts other than the movable part 20. The movable part 20 bends flexibly when operated by the operating device 100, causing the distal end 10a of the tubular member 10 to be flexibly deflected. On the other hand, the parts of the tubular member 10 other than the movable part 20 have flexibility that allows them to deform flexibly according to the shape of tubular organs and blood vessels in the body, but they are designed to be difficult to bend when operated by the operating device 100. In other words, when a user operates the device 100, only the movable part 20 bends in response to the operation, and the parts other than the movable part 20 do not bend substantially.

[0029] A first operating wire W1 and a second operating wire W2 are inserted inside the tubular member 10. The first operating wire W1 and the second operating wire W2 are operation transmission members that transmit operations from the proximal operating device 100 to the distal end of the tubular member 10, thereby bending the movable part 20. Specifically, the operating device 100 pulls either the first operating wire W1 or the second operating wire W2 and moves it proximal in the axial direction, thereby bending the movable part 20. The first operating wire W1 and the second operating wire W2 constitute the operating wires of the present invention.

[0030] The first operating wire W1 and the second operating wire W2 can be made of a metal (such as stainless steel) that has enough flexibility to bend in accordance with the bending of the tubular member 10 including the movable part 20. The first operating wire W1 and the second operating wire W2 are designed to bend the movable part 20 by moving them proximal to the axial direction through operation of the operating device 100. Alternatively, the first operating wire W1 and the second operating wire W2 may be made of a material that has rigidity in the axial direction and can transmit force from the proximal to the distal side.

[0031] The proximal end of the tubular member 10 is connected to the distal end of the operating device 100. The operating device 100 is placed outside the body when the user of the medical device 1 performs treatment or examination inside the body. The operating device 100 is configured to bend the movable part 20 of the tubular member 10 by displacing a first operating wire W1 or a second operating wire W2 attached to the distal end of the tubular member 10 in the axial direction. The operating device 100 only needs to be capable of pulling the first operating wire W1 and the second operating wire W2, and the configuration of the operating device 100 is not particularly limited.

[0032] The tubular member 10, as well as the first operating wire W1 and the second operating wire W2, will be described with reference to Figure 2. Figure 2 is a cross-sectional view along line AA in Figure 1.

[0033] The distal end of the tubular member 10 is provided with a movable part 20 that can be bent using an operating device 100. By operating the bending motion of the movable part 20 with the operating device 100, the distal end of the tubular member 10 can be deflected in a desired deflection direction.

[0034] As shown in the cross-sectional view of Figure 2, the tubular member 10 has a tubular structure with a lumen formed along its extending direction. A main lumen 33 is formed approximately in the center of the cross-section of the tubular member 10, along the axial direction of the tubular member 10. The main lumen 33 can, for example, be used to insert various medical instruments or to allow fluids to flow through it.

[0035] Wire lumens 31a, 31b, 32a, and 32b are formed in the tube wall between the outer surface of the tubular member 10 and the main lumen 33, for inserting the first operating wire W1 and the second operating wire W2. As an example, as shown in Figure 2, the tubular member 10 has a pair of wire lumens 31a, 31b and a pair of wire lumens 32a, 32b, i.e., a total of four wire lumens 31a, 31b, 32a, and 32b. Each wire lumen 31a, 31b, 32a, and 32b is formed to open at the distal end 10a and the proximal end 10b of the tubular member 10, similar to the main lumen 33.

[0036] As described later, a first operating wire W1 is inserted through a pair of wire lumens 31a and 31b, and a second operating wire W2 is inserted through a pair of wire lumens 32a and 32b. The wire lumens 31a, 31b, 32a, and 32b constitute the wire insertion passages of the present invention. The pair of wire lumens 31a, 31b and the pair of wire lumens 32a, 32b are positioned at approximately 180° opposite each other in the circumferential direction with respect to the central axis of the tubular member 10.

[0037] To reinforce the tubular member 10 and suppress its twisting, a braided layer may be provided on the tubular member 10, which consists of a reinforcing member made of braided wire, such as stainless steel. The braided layer may be provided on a part of the tubular member 10, for example, only on the first rigid section 11 or the second rigid section 13, or particularly only on the first rigid section 11, as described later. The tubular member 10 may have multiple lumens other than the wire lumen, and may be a multilayer tube.

[0038] The configuration of the vicinity of the distal end 10a of the tubular member 10 will be described with reference to Figures 3(a) and 3(b). Figure 3 shows the vicinity of the distal end 10a of the tubular member 10 in this embodiment, where (a) is a schematic perspective view showing the vicinity of the distal end 10a of the tubular member 10, and (b) is a transmission view for explaining the inside of the tubular member 10. Note that the main lumen 33 is omitted from the illustration in Figure 3(b).

[0039] The distal end 10a of the tubular member 10 is provided with a tip 50 made of, for example, metal. The tip 50 protects the distal end 10a of the tubular member 10 and, by being formed in a tapered shape, reduces the resistance to inserting the tubular member 10 into the body. The tip 50 is fixed to the distal end 10a of the tubular member 10.

[0040] The tip 50 is provided with a through-hole 55a along its central axis. The through-hole 55a communicates with the main lumen 33 of the tubular member 10, and the main lumen 33 of the tubular member 10 communicates with the outside through this through-hole 55a.

[0041] The tip 50 has a pair of side recesses 56 and 57 formed on its proximal side surface. Wire insertion holes 56a and 56b are formed in the side recess 56. Similarly, wire insertion holes 57a and 57b are formed in the side recess 57. The wire insertion holes 56a, 56b, 57a, and 57b are provided to correspond to the opening positions of the wire lumens 31a, 31b, 32a, and 32b that open at the distal end 10a of the tubular member 10, and the first operating wire W1 and the second operating wire W2, which are inserted through the wire lumens 31a, 31b, 32a, and 32b, are inserted through the wire insertion holes 56a, 56b, 57a, and 57b, respectively.

[0042] As shown in Figures 2 and 3(b), a single operating wire (first operating wire W1) is inserted through the wire lumens 31a and 31b, and a single operating wire (second operating wire W2) is inserted through the wire lumens 32a and 32b.

[0043] The first operating wire W1, which is inserted through the wire lumens 31a and 31b, is inserted through wire insertion holes 56a and 56b of the tip 50, which are provided corresponding to the wire lumens 31a and 31b. The first operating wire W1 has a length slightly longer than about twice the length of the tubular member 10, and a folded intermediate portion W1c, which corresponds to approximately halfway along the axial direction of the wire, is folded back in the side recess 56 of the tip 50. With the folded intermediate portion W1c as a reference, the operating wire W1a at one end is inserted through the wire insertion hole 56a into the wire lumen 31a, and the operating wire W1b at the other end is inserted through the wire insertion hole 56b into the wire lumen 31b. When the operating wires W1a and W1b are pulled proximally, the folded intermediate portion W1c is configured to engage with the tip 50 due to the tensile force.

[0044] The second operating wire W2, which is inserted through the wire lumens 32a and 32b, is inserted through wire insertion holes 57a and 57b of the tip 50, which are provided corresponding to the wire lumens 32a and 32b. The second operating wire W2 has a length slightly longer than about twice the length of the tubular member 10, and a folded intermediate portion W2c, which corresponds to approximately halfway along the axial direction of the wire, is folded back in the side recess 57 of the tip 50. With the folded intermediate portion W2c as a reference, the operating wire W2a at one end is inserted through the wire insertion hole 57a into the wire lumen 32a, and the operating wire W2b at the other end is inserted through the wire insertion hole 57b into the wire lumen 32b. When the operating wires W2a and W2b are pulled proximally, the folded intermediate portion W2c is configured to engage with the tip 50 due to the tensile force.

[0045] In this way, by folding the wire back at the distal end 10a of the tubular member 10, the number of parts can be reduced, thereby reducing the amount of work required during manufacturing, and structural limitations can be minimized.

[0046] One end of the first operating wire W1, operating wire W1a, extends along the tubular member 10 while being inserted through the wire lumen 31a, and the proximal end of operating wire W1a is guided into the operating device 100. Similarly, the other end of the first operating wire W11, operating wire W1b, extends along the tubular member 10 while being inserted through the wire lumen 31b, and the proximal end of operating wire W1b is guided into the operating device 100. When operating wires W1a and W1b are pulled proximal by the operating device 100, the movable part 20 bends toward the side where the side recess 56 of the tip 50 is located (in the direction of arrow α shown in Figure 5, which will be described later).

[0047] One end of the second operating wire W2, W2a, extends along the tubular member 10 while being inserted through the wire lumen 32a, and the proximal end of operating wire W2a is guided into the operating device 100. Similarly, the other end of the second operating wire W2, W2b, extends along the tubular member 10 while being inserted through the wire lumen 32b, and the proximal end of operating wire W2b is guided into the operating device 100. When operating wires W2a and W2b are pulled proximal by the operating device 100, the movable part 20 bends toward the side where the side recess 57 of the tip 50 is located (in the direction of arrow β shown in Figure 5, which will be described later).

[0048] The configuration of the tubular member 10 will be described with reference to Figure 4. Figure 4 is a plan view illustrating the configuration of the tubular member 10 of the medical device 1 in this embodiment.

[0049] As shown in Figure 4, the tubular member 10 is composed of a first rigid portion 11, a flexible portion 12, and a second rigid portion 13 integrated together. The first rigid portion 11, the flexible portion 12, and the second rigid portion 13 are arranged in this order from the proximal side. That is, the flexible portion 12 is located distal to the first rigid portion 11, and the second rigid portion 13 is located distal to the flexible portion 12.

[0050] The soft part 12 has a structure that is more flexible than the first rigid part 11 and the second rigid part 13. The movable part 20 is composed of the soft part 12. On the other hand, the first rigid part 11 and the second rigid part 13 have a structure that is more rigid than the soft part 12. The first rigid part 11 and the second rigid part 13 have flexibility that allows them to bend flexibly within the body, but they are configured to be difficult to bend (substantially not bend) during the pulling operation of the first operating wire W1 and the second operating wire W2. As a result, the tubular member 10 has a configuration in which the flexibility ranges different along the axial direction.

[0051] The proximal end of the first rigid portion 11 constitutes the proximal end 10b of the tubular member 10, and the distal end of the second rigid portion 13 constitutes the distal end 10a of the tubular member 10. In other words, the first rigid portion 11 and the second rigid portion 13 are positioned at both ends of the tubular member 10, and the highly flexible soft portion 12 is sandwiched between the less flexible first rigid portion 11 and the second rigid portion 13.

[0052] The flexible portion 12 is located near the distal end 10a of the tubular member 10, and the majority of the proximal side of the tubular member 10 is composed of the first rigid portion 11. The axial length of the first rigid portion 11 (length L2 in Figure 4) is preferably 90% or more of the total length of the tubular member 10 (length L1 in Figure 4) (L2 / L1 ≥ 90 / 100). The flexible portion 12 constitutes the movable portion 20 of the tubular member 10, and the movable portion 20 is located near the distal end 10a. The axial length of the flexible portion 12 and the axial length of the second rigid portion 13 should be set to appropriate lengths depending on the application and use.

[0053] For example, the soft part 12 is formed to have a porous structure containing more pores than the first rigid part 11 and the second rigid part 13, while the first rigid part 11 and the second rigid part 13 are formed to have a solid structure with fewer pores and a higher density than the soft part 12. The first rigid part 11 and the second rigid part 13 and the soft part 12 have different physical properties, as illustrated below. The structure and physical properties of the first rigid part 11 and the second rigid part 13 may be the same or different, but in either case, the soft part 12 is configured to have higher flexibility than the first rigid part 11 and the second rigid part 13.

[0054] The specific gravity of the first rigid portion 11 and the second rigid portion 13 is not particularly limited, but is preferably 0.80 to 2.20. The specific gravity of the soft portion 12 is not particularly limited, but is preferably 0.10 to 2.00. Furthermore, the ratio of the specific gravity of the first rigid portion 11 and the second rigid portion 13 to the specific gravity of the soft portion 12 (soft portion / rigid portion) is preferably 0.30 to 0.95, more preferably 0.40 to 0.90, and even more preferably 0.50 to 0.90 in at least a portion of the tubular member 10 in the axial direction. As a result, most of the tubular member 10, including the proximal side, becomes highly rigid due to the action of the first rigid portion 11. In addition, the movable portion 20 provided near the distal end 10a of the tubular member 10 becomes highly flexible due to the action of the soft portion 12. Furthermore, a second rigid section 13 that is substantially non-bending can be positioned distal to the movable section 20, which includes the soft section 12. The specific gravity test method conforms to the liquid weighing method described in JIS Z 8807, and the standard substance is water.

[0055] The ratio of the bending stress in the first rigid section 11 and the second rigid section 13 to the bending stress in the flexible section 12 (flexible section / rigid section) is preferably 0.10 or more and less than 1.0. If the ratio related to the bending stress is 0.40 or more and less than 1.0, a certain bending stress can be secured even in the flexible section 12, so the tubular member 10 will have excellent mechanical strength. On the other hand, if the ratio related to the bending stress is 0.10 or more and less than 0.40, the tubular member 10 will have excellent flexibility as well as mechanical strength. The bending stress was measured by performing a bending test on a bending test machine and measuring the reaction force when indented by 5.0 mm. The tube length is 100 mm, the compression section shape is a cylindrical shape with a diameter of 10 mm, the distance between supports is 60 mm, the support member shape is a cylindrical shape with a diameter of 10 mm, and the indentation speed is 50 mm / min.

[0056] The structure of the boundary between the first rigid portion 11 and the second rigid portion 13 and the soft portion 12 is not particularly limited, but for example, transition portions 14 and 15 in which the structure and physical properties gradually change along the axial direction may be provided at either or both of the boundary portions between the first rigid portion 11 and the soft portion 12, and the boundary portion between the soft portion 12 and the second rigid portion 13. In this embodiment, as shown in Figure 4, the transition portion 14 is located at the boundary portion between the first rigid portion 11 and the soft portion 12, and the transition portion 15 is located at the boundary portion between the soft portion 12 and the second rigid portion 13. The axial length of the transition portions 14 and 15 is not particularly limited. The transition portions 14 and 15 located near the boundary portion with the soft portion 12 have a structure and physical properties similar to the soft portion 12. Therefore, as shown in Figure 4, the movable portion 20 includes the entire soft portion 12 and parts of the transition portions 14 and 15.

[0057] When transition sections 14 and 15 are provided, the load does not concentrate near the boundary between the first rigid section 11 and the soft section 12, or near the boundary between the soft section 12 and the second rigid section 13, when the tubular member 10 is deflected. As a result, bending and crushing are less likely to occur, and the tubular member 10 becomes more kink-resistant. On the other hand, the configuration may also be made without transition sections 14 and 15. In this case, the rigidity of the tubular member 10 can be increased by the action of the first rigid section 11 and the second rigid section 13.

[0058] The soft portion 12 itself may be designed to gradually become more flexible towards the distal end. In this case, since the flexibility of the tubular member 10 gradually increases towards the distal end, the movable portion 20, which includes the soft portion 12, will bend more significantly towards the tip.

[0059] Preferably, in the tubular member 10, the inner and outer circumferential surfaces of the first rigid portion 11, the flexible portion 12, and the second rigid portion 13 are formed smoothly in the axial direction, and the surfaces are flush with no joints or steps at each boundary. By smoothing the inner circumferential surface of the tubular member 10 (the circumferential surfaces of the main lumen 33 and the wire lumens 31a, 31b, 32a, and 32b), the ease of insertion of various treatment instruments into the main lumen 33 can be improved, and the frictional resistance of the first operating wire W1 and the second operating wire W2 can be reduced. Furthermore, by smoothing the outer circumferential surface of the tubular member 10, an increase in the insertion resistance of the tubular member 10 can be prevented, and the ease of insertion into tubular organs, blood vessels, treatment instrument insertion channels of flexible endoscopes can be improved.

[0060] The manufacturing method for the tubular member 10 is not particularly limited. Examples include extrusion molding, injection molding, and a method of winding a film into a tube. If necessary, stretching, chemical treatment, plasma treatment, laser treatment, electron crosslinking treatment, etc., may be applied. In particular, when the entire tubular member 10 is made of polytetrafluoroethylene, an unfired tube may be manufactured by extrusion molding, the parts corresponding to the first rigid part 11 and the second rigid part 13 may be sintered, and then the part corresponding to the soft part 12 may be stretched to make it porous before being sintered. By adjusting the stretching rate (degree of stretching) during the stretching process, the porosity of the porous soft part 12 and transition parts 14 and 15 can be adjusted to appropriately set the flexibility of the soft part 12 and transition parts 14 and 15. The degree of porosity of the transition parts 14 and 15 should be appropriately varied along the axial direction.

[0061] The first rigid portion 11, the flexible portion 12, the second rigid portion 13, and even the transition portions 14 and 15 can all be made of biocompatible polymer materials such as polyurethane, polyethylene, polypropylene, or fluororesins such as polytetrafluoroethylene. In particular, by adjusting the extent and degree of porosity in a single tube, a tubular member 10 can be created that integrally includes the first rigid portion 11, the flexible portion 12, the second rigid portion 13, and even the transition portions 14 and 15.

[0062] Furthermore, it is preferable that the soft portion 12 has isotropy in the circumferential direction. This allows the soft portion 12 to have uniform flexibility and bending mobility in all directions, making it easier to set up the movable portion 20 that bends in multiple directions.

[0063] Referring to Figure 5, the deflection operation of the tubular member 10 in the medical device 1 will be explained. Figure 5 is a diagram illustrating the bending operation of the movable part 20 of the tubular member 10 in this embodiment, and is a schematic plan view showing the distal end of the tubular member 10. Figure 5 schematically shows the state in which no deflection operation is performed by the operating device 100 (neutral state) and the state in which the distal end of the tubular member 10 is deflected to the left and right, respectively.

[0064] When the operating device 100 is operated to pull the first operating wire W1 (operating wires W1a and W1b) proximal, the movable part 20 can be bent toward the side where the side recess 56 of the tip 50 is located (direction of arrow α). At this time, the movable part 20, which is composed of the soft part 12 and parts of the transition parts 14 and 15, bends, but the first rigid part 11 and the second rigid part 13 do not bend substantially. As a result, the second rigid part 13 located distal to the movable part 20 remains in a straight line, while only the movable part 20 bends in the direction of arrow α. In this state, the first rigid part 11 and the second rigid part 13, which are positioned to sandwich the soft part 12, remain in a straight line while the movable part 20 bends, so the tubular member 10 takes on a shape that is deflected in the direction of arrow α midway along the axial direction.

[0065] When the operating device 100 is operated to pull the second operating wire W2 (operating wires W2a and W2b) proximal, the movable part 20 can be bent toward the side where the side recess 57 of the tip 50 is located (direction of arrow β). Similarly, in this case as well, the movable part 20, which is composed of the soft part 12 and parts of the transition parts 14 and 15, bends, but the first rigid part 11 and the second rigid part 13 do not bend substantially. As the movable part 20 bends while the first rigid part 11 and the second rigid part 13, which are positioned to sandwich the soft part 12, are kept in a straight line, the tubular member 10 takes on a shape that is deflected in the direction of arrow β midway along the axial direction.

[0066] As shown in Figure 8, in conventional medical devices 200, the tubular member 210 has a movable portion 220 within a predetermined range from its distal end 210a. However, in dilated areas (wide spaces) or bifurcations of tubular organs or blood vessels, for example, if the desired position for advancing the distal end 210a is far away, it may not be possible to reach that position, making it difficult to advance the distal end 210a smoothly and appropriately.

[0067] Figure 6 shows the state in which the tubular member 10 of the medical device 1 in this embodiment is inserted into the body. Figure 6 schematically shows the ascending aorta 301, the aortic arch 302, the descending aorta 303, and the blood vessels branching from the aortic arch 302. Similar to Figure 8 described above, Figure 6 schematically shows the state in which the medical device 1, as a guiding catheter for the circulatory system, is inserted into the aortic arch 302.

[0068] For example, if a tubular member 10 that has reached the aortic arch 302 from the brachiocephalic artery 311 is to be inserted into the left common carotid artery 312 or the left subclavian artery 313, as shown in Figure 8, with conventional medical devices 200, the distal end 210a of the tubular member 210 may not reach the left common carotid artery 312 or the left subclavian artery 313, making insertion and progression through the target pathway difficult.

[0069] In contrast, in this embodiment, even when the movable part 20 of the medical device 1 is bent, the second rigid part 13 located distal to the movable part 20 maintains a straight-line extension. This allows the straight-line extension of the second rigid part 13 to be rotated starting from the movable part 20, thereby expanding the reach of the distal end 10a compared to the conventional medical device 200. For example, as shown in Figure 6, it becomes easier to reach the left subclavian artery 313 with the distal end 10a of the tubular member 10. By expanding the reach of the distal end 10a of the tubular member 10 in this way, the ability of the tubular member 10 to select the target path can be improved.

[0070] Furthermore, the medical device 1 in this embodiment has the effect of improving the mounting stability of the tip 50 to the distal end 10a of the tubular member 10. Figure 7 is a diagram illustrating the mounting stability of the tip 50 to the distal end 10a of the tubular member 10 in this embodiment, where (a) is a plan view showing the vicinity of the distal end 210a of the tubular member 210 of a prior art medical device 200, and (b) is a plan view showing the vicinity of the distal end 10a of the tubular member 10 of the medical device 1 in this embodiment.

[0071] In conventional medical devices 200, a predetermined range from the distal end 210a of the tubular member 210 is a movable part 220, and the distal end 210a that the tip 250 contacts is made of a highly flexible material. For example, as shown in Figure 7(a), when the tubular member 210 is deflected by pulling the first operating wire W1 proximal, the bending inner side (the side where the first operating wire W1 is located) is pulled proximal. At this time, a force is applied to the distal end 210a that contacts the tip 250, pushing it proximal by the tip 250 on the side where the first operating wire W1 is located. However, no tension is generated in the second operating wire W2, and no force from the tip 250 is applied to the bending outer side (the side where the second operating wire W2 is located). Therefore, the contact surfaces where the distal end 210a and the tip 250 face each other may tilt inward, potentially creating a gap G on the outside. When such gaps G occur, unintended loads may be placed on the distal end 210a or tip 250 of the tubular member 210, potentially causing deformation or damage.

[0072] On the other hand, in the medical device 1 of this embodiment, the distal end 10a that the tip 50 contacts is composed of a second rigid portion 13. Since the second rigid portion 13 does not bend substantially during the traction operation of the operating device 100, no gap G is created at the contact surfaces where the distal end 10a and the tip 50 face each other, and they can maintain contact with each other. As a result, the mounting stability and durability of the tip 50 are improved.

[0073] The operation of the medical device 1 in this embodiment will be described below.

[0074] The medical device 1 in this embodiment includes a long tubular member 10 having wire lumens 31a, 31b, 32a, and 32b formed along the axial direction, and a first operating wire W1 and a second operating wire W2 inserted through the wire lumens 31a, 31b, 32a, and 32b and attached to the distal end 10a of the tubular member 10. The tubular member 10 is integrally composed of a soft portion 12 that bends when pulled by the first operating wire W1 and the second operating wire W2, and a first rigid portion 11 and a second rigid portion 13 that are difficult to bend when pulled by the first operating wire W1 and the second operating wire W2. The soft portion 12 is located distal to the first rigid portion 11, and the second rigid portion 13 is located distal to the soft portion 12.

[0075] According to the above configuration, a second rigid section 13, which is less likely to bend during the traction operation of the first operating wire W1 and the second operating wire W2, is provided distal to the soft section 12, which acts as the movable section 20 of the tubular member 10. Therefore, even if the desired position for advancing the distal end 10a of the tubular member 10 is far away, the second rigid section 13 can reach it, allowing the distal end 10a to advance smoothly and appropriately. Furthermore, since the tubular member 10 is integrally constructed in the order of the first rigid section 11, the soft section 12, and the second rigid section 13 from the proximal side, a medical device 1 can be realized that is excellent in stability and strength, as well as in the bending mobility of the movable section 20. In addition, by appropriately setting the axial length of the second rigid section 13, the position of the movable section 20 can be flexibly adjusted according to the case and procedure. Furthermore, by arranging the second rigid portion 13 at the distal end of the tubular member 10, including the distal end 10a, the distal end 10a is made rigid, thereby improving the mounting stability of the tip 50 to the distal end 10a.

[0076] In this embodiment, the medical device 1 has transition sections 14 and 15 positioned between the soft section 12 and at least one of the first rigid section 11 and the second rigid section 13, and the transition sections 14 and 15 may smoothly change the structure of the soft section 12 and the structure of at least one of the first rigid section 11 and the second rigid section 13 in the axial direction.

[0077] According to the above configuration, the transition sections 14 and 15 continuously change the structure between the soft section 12 and the first rigid section 11 and the second rigid section 13, making it possible to achieve both strength stability and flexibility of the movable section 20.

[0078] In this embodiment, the medical device 1 may have a tubular member 10 that has a smooth circumferential surface in the axial direction.

[0079] With the above configuration, the insertion resistance into the body and the frictional resistance during the traction operation of the first operating wire W1 and the second operating wire W2 can be reduced, thereby improving the insertability and operability of the medical device 1.

[0080] In this embodiment, the axial length of the first rigid portion 11 of the medical device 1 may be 90% or more of the total length of the tubular member 10.

[0081] According to the above configuration, a medical device 1 can be realized in which the majority of the proximal side of the tubular member 10 consists of a first rigid part 11, and a soft part 12 as a movable part 20 and a second rigid part 13 are arranged at the distal end.

[0082] In this embodiment, the medical device 1 may have a tubular member 10 made of polytetrafluoroethylene, and the soft portion 12 may be porous.

[0083] According to the above configuration, a soft part 12 can be realized that is excellent in various properties such as biocompatibility and chemical resistance, and also has excellent flexibility due to its porous structure.

[0084] The embodiments described above are provided to facilitate understanding of the present invention and do not limit it. Each component disclosed in the embodiments described above is intended to include all design modifications and equivalents that fall within the technical scope of the present invention. [Explanation of symbols]

[0085] 1,200 medical devices 10, 210 Tubular member 10a, 210a distal end 10b Proximal end 11 First rigid part 12 Soft part 13 Second rigid part 14, 15 Transition Section 20, 220 Moving parts 31a, 31b, 32a, 32b Lumen for wire (wire insertion passage) 33 main lumens 50, 250 tip 55a through hole 56, 57 side recess 56a, 56b, 57a, 57b Wire insertion holes 100 Operating device 301 Ascending aorta 302 Aortic arch 303 Descending aorta 311 Innominate artery 312 Left common carotid artery 313 Left subclavian artery W1 First operating wire (operating wire) W1a, W1b, W2a, W2b operating wires W1c, W2c folded middle part W2 Second operating wire (operating wire)

Claims

1. A long, tubular member having flexibility and having a wire insertion passage formed along its axial direction, The operating wire is inserted through the wire insertion passage and attached to the distal end of the tubular member, The tubular member is integrally composed of a flexible portion that bends when pulled by the operating wire, and a first rigid portion and a second rigid portion that are difficult to bend when operated by the operating wire. A medical device characterized in that the soft portion is positioned distal to the first rigid portion, and the second rigid portion is positioned distal to the soft portion.

2. A transition portion is provided between the soft portion and at least one of the first rigid portion and the second rigid portion. The medical device according to claim 1, characterized in that the transition portion smoothly changes the structure of the soft portion and the structure of at least one of the first rigid portion and the second rigid portion in the axial direction.

3. The medical device according to claim 1 or 2, characterized in that the tubular member has a smooth circumferential surface in the axial direction.

4. The medical device according to claim 1 or 2, characterized in that the axial length of the first rigid portion is 90% or more of the total length of the tubular member.

5. The medical device according to claim 1 or 2, characterized in that the tubular member is made of polytetrafluoroethylene and the soft portion is porous.

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