JP2004275200A - Catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catheter, soft on the tip side, having a hard tube near a hand operating part, in which a prescribed range near the hand operating part is gradually varied from soft to hard, and with kink-proofing capability, etc. <P>SOLUTION: In the catheter 1, the base end side of the flexible tube 4 is held by a holder member H, and the tube 4 near the holder member H has a coil-shaped reinforcing member 42 inside a tube wall. The base end side of the coil-shaped reinforcing member 42 is covered with a pipe-shaped reinforcing member 43, which is held in the holder member H. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a catheter that is inserted into a living body and performs treatment and diagnosis of various parts of a human body.
[0002]
[Prior art]
2. Description of the Related Art In recent years, an ultrasonic diagnostic apparatus has been used when performing treatment or diagnosis of various parts of the human body. This ultrasonic diagnostic apparatus inserts an ultrasonic catheter into a body cavity such as a coronary artery or other blood vessels of the heart, a lumen such as a bile duct, or a urethra (hereinafter, collectively referred to as a “lumen”), and observes a corresponding portion. Make a diagnosis.
[0003]
Therefore, since the ultrasonic catheter is inserted into a meandering lumen, the ultrasonic catheter is formed of a flexible, long and small-diameter tube, and a probe portion is provided at a distal end thereof. The probe unit is operated by a hand operation unit connected to the external unit, receives a reflected wave of the ultrasonic wave emitted from the ultrasonic oscillator, and displays the reflected wave on a monitor or the like of the external unit.
[0004]
The tube has a cable for transmitting an electric signal for connecting the ultrasonic transducer at the tip and an external circuit therein, and a mechanically rotating or reciprocating the transducer so that a predetermined region in a body cavity can be observed at 360 °. A predetermined inner diameter is required because a driving force transmitting body (drive shaft) to be inserted is inserted. However, in consideration of mobility and workability in a lumen, it is preferably thin and flexible. Considering the torque transmission in the case of the above, some strength is required.
[0005]
Various types of such ultrasound catheters have been proposed in the past. For example, as in Patent Literature 1 below, the outer tube of the tube is formed of a superelastic metal (a metal having a property of returning to an original shape even when deformed to a region where ordinary metal plastically deforms at an operating temperature), A drive shaft in the outer tube is a hollow coil, an ultrasonic vibrator is attached to the tip of the hollow coil, and a drive shaft in the outer tube is a hollow coil as in Patent Document 2 described below. As in Document 3, four lumens are formed in the tubular element, each lumen is made into a torque tube, a balloon tube, and an injection tube. The outside of this tubular element is covered with a knitted shield, and an ultrasonic vibrator is provided at the tip. As described in Patent Literature 4 below, the outer tube is formed by using a flexible material such as a resin.
[0006]
[Patent Document 1]
JP-A-7-95980 (see paragraphs [0014] to [0021], FIG. 1)
[Patent Document 2]
JP-A-2002-360578 (paragraph numbers [0022] and [0023]; see FIGS. 1 and 2)
[Patent Document 3]
Japanese Patent Publication No. 7-57222 (see FIG. 4)
[Patent Document 4]
JP-A-11-137557 (paragraph numbers [0034] and [0035]; see FIG. 1)
[0007]
[Problems to be solved by the invention]
Regarding the actual handling of such an ultrasonic catheter, it is desirable that the distal end side is relatively flexible for guiding during insertion into a meandering lumen and for preventing damage to the lumen wall, On the side, there is a trade-off demand that it is desirable for the operator to be relatively hard so that it can be easily handled.
[0008]
However, there is no conventional ultrasonic catheter that satisfies such a demand, and at least from the viewpoint of preventing damage, a flexible material capable of deforming a tube is used, and a drive shaft in the tube is a hollow coil. Therefore, the entire tube is flexible, and the tube near the hand operation unit is easily deformed during use, which causes a problem in operability.
[0009]
In addition, ultrasonic catheters include a type in which a guide wire is inserted in advance to a predetermined site in the body and a tube is inserted along the guide wire, and a type in which a guide wire is not used.In the latter case, the entire tube is flexible. Then, there is a problem in terms of operability.
[0010]
The present invention has been made in order to solve the above-described problem, and the distal end side is a flexible tube near the hand operation unit, and a predetermined range near the hand operation unit is gradually changed from a flexible portion to a hard portion. It is an object of the present invention to provide a catheter which is changed and has kink resistance and the like.
[0011]
[Means for Solving the Problems]
The object of the present invention is achieved by the following ultrasonic catheter.
[0012]
(1) A catheter in which a proximal end of a flexible tube is held by a holding member, wherein the tube in the vicinity of the holding member has a coiled reinforcing member inside the tube wall, and the coiled reinforcing member is provided. A base end side of which is covered with a pipe-shaped reinforcing member, and the pipe-shaped reinforcing member is held by the holding member.
[0013]
(2) The catheter according to (1), wherein the pipe-shaped reinforcing member is provided with a rigidity weakening portion in a predetermined region from a distal end portion to a proximal end side.
[0014]
(3) The catheter according to (2), wherein the rigidity weakening portion is a spiral slit.
[0015]
(4) The helical slit has a constant width, and the interval between the helical slits is gradually increased from a distal end side to a proximal end side of the pipe-shaped reinforcing member. The catheter of (3).
[0016]
(5) The catheter according to (3) or (4), wherein the spiral slit is formed from a tip of the pipe-shaped reinforcing member to a middle of the holding member.
[0017]
(6) The catheter according to any one of (3) to (5), wherein the coil-shaped reinforcing member and the pipe-shaped reinforcing member are joined at or near the terminal end of the spiral slit on the holding member side.
[0018]
(7) The catheter according to (6), wherein the joining includes forming a through hole in the pipe-shaped reinforcing member, and filling the through hole with a filler.
[0019]
(8) The tube has a base end portion formed of three layers of a tube layer, a coil-shaped reinforcing member layer, and a pipe-shaped reinforcing member layer; an intermediate portion formed of two layers of the tube layer and the coil-shaped reinforcing member layer; The catheter according to any one of (1) to (7), further including a distal end portion formed of only a tube layer.
[0020]
(9) The catheter according to the above (8), wherein a guide member is further provided at a distal end of the distal end portion composed of only the tube layer.
[0021]
(10) The tube has at least one lumen, and further includes a drive shaft inserted into the lumen, and an ultrasonic vibrator provided at a tip of the drive shaft. The catheter according to the above (8) or (9), wherein the child is located at a distal end portion composed of only the tube layer.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0023]
FIG. 1 is a schematic front view showing the entire embodiment of the present invention, FIG. 2 is a sectional view showing a distal end portion of the tube of the embodiment, and FIG. 3 is a sectional view showing a proximal end portion of the tube.
[0024]
The embodiment shown in FIG. 1 is, for example, an ultrasonic catheter 1 for an ultrasonic diagnostic apparatus that performs treatment or diagnosis of a vascular stenosis or the like that causes myocardial infarction or the like. In general, the ultrasonic catheter 1 includes a flexible guide member 2, a probe unit 3 for transmitting and receiving ultrasonic waves, a long tube 4, a hand operation unit 5 operated by an operator, and a hand operation from the distal end. It has an external unit 7 connected to the section 5 and does not use a guide wire.
[0025]
Further details will be described. As shown in FIG. 2, the guide member 2 has a tapered core 21 having a base end fused to the inner tube N at the center, and a coil-shaped member 22 provided outside the tapered core 21. The tapered core 21 is made of, for example, a highly elastic metal material such as stainless steel or a Ni—Ti alloy, and is a shaft having a tapered shape as a whole. ing. Further, the distal end portion 21a is brazed so as to have an arc-shaped cross section, thereby preventing the inner wall of the blood vessel from being damaged.
[0026]
The coil-shaped member 22 has a distal-side coil-shaped member 22a and a proximal-side coil-shaped member 22b. When the catheter 1 is inserted into the body, the distal-side coil-shaped member 22a functions as an X-ray contrast marker (a hatched portion in the drawing) for identifying the position of the catheter 1 so that the distal-side coil-shaped member 22a is made of a radiopaque material or It is constituted by a material having such a material in a part. With this configuration, the position of the catheter 1 in the living body, particularly the position of the distal end portion, can be confirmed under fluoroscopy without separately installing a contrast marker.
[0027]
Here, examples of the X-ray opaque material include gold, silver, platinum, tungsten, palladium, and alloys thereof.
[0028]
The base-side coil-shaped member 22b is made of a highly elastic metal material, for example, stainless steel, and the inner tube N of the tube 4 described later is fused to the outside to prevent the guide member 2 from falling off. I have.
[0029]
The distal coil side member 22a and the proximal coil side member 22b are provided with brazing portions 23a and 23b at respective intermediate positions for adjusting the elasticity of the guide member 2.
[0030]
The guide member 2 has a large diameter at the base end portion 21 b of the tapered core 21 so as to be firmly connected to the probe portion 3, and is fused to the first coil member 31 of the probe portion 3 by the reinforcing tube 24.
[0031]
The reinforcing tube 24 is formed by filling an adhesive. Such an adhesive is not particularly limited, but a photocurable or thermosetting adhesive is preferable. In particular, a photocurable adhesive such as an ultraviolet curable adhesive is preferable because the degree of curing can be easily adjusted.
[0032]
The probe unit 3 is a part for substantially diagnosing the inside of a blood vessel. As shown in FIG. 2, a cylinder provided at the tip of a drive shaft S is provided in the inner tube N in addition to the first coil member 31. The housing 32 includes a partially cut-out housing 32, an ultrasonic vibrator 33 installed in the housing 32 for transmitting and receiving ultrasonic waves, and a second coil member 34 attached to a tip of the housing 32. .
[0033]
The second coil member 34 has a tip portion protruding into the first coil member 31 for the purpose of preventing vibration. When the second coil member 34 rotates with the rotation of the drive shaft S, the tip of the second coil member 34 hits the inner peripheral surface of the first coil member 31 to prevent vibration and stably rotate the ultrasonic vibrator 33 and the like. Become.
[0034]
The first coil member 31 is made of the same X-ray opaque material as described above, and serves as a sensor marker for confirming the position of the ultrasonic transducer 33, in other words, the position where an ultrasonic image is obtained. Function.
[0035]
The tube 4 is a long and flexible tube extending from the rear end of the guide member 2 to the hand operation unit 5, and the drive shaft S is rotatably provided in the inner tube N. The drive shaft S has a layered structure in which a plurality of coils are wrapped so as to have flexibility and rotational torque transmission characteristics. For example, the winding direction is changed as follows, for example, right-handed layer-left-handed layer-right-handed layer. It is a tubular body having an alternately changed configuration, the outer diameter of which is constant from the beginning to the end. With this configuration, when a torsional force is applied, the coils of the respective layers are mutually tightened, and torque transmission is reliably performed.
[0036]
However, the winding direction or the number of layers to be wrapped can be freely selected depending on each model, performance, and the like. As a specific example of the drive shaft S, stainless steel, a piano wire or the like having a diameter or a thickness of 0.001 to 0.5 mm is formed in a hollow coil shape having an outer diameter of 0.1 to 4 mm.
[0037]
The rotation speed of the drive shaft S varies depending on the pathological condition or the part to be diagnosed, but is generally 30 times / sec because the monitor image is 30 frames / sec.
[0038]
The rotation of the drive shaft S makes it possible to observe the inside of the lumen 360 degrees, but to observe a wider range, the catheter 1 may be moved in the axial direction. The movement in the axial direction may be performed by the operator, or may be performed by the external unit 7.
[0039]
Note that a signal line 55 (see FIG. 7) for transmitting a signal detected by the ultrasonic transducer 33 to the external unit 7 via the hand operation unit 5 is passed inside the drive shaft S.
[0040]
The tube 4 has a structure in which the base end side is held by a rigid holding member H. In the present embodiment, as shown in FIG. 3, the rigidity gradually changes up to the main body 50 of the hand operation unit 5. It has such a configuration. In other words, the inner tube N near the anti-kink protector 63 has a coil-shaped reinforcing member 42 provided on the outer periphery of the inner tube N and a pipe-shaped member having a certain rigidity covering the base end side of the coil-shaped reinforcing member 42. The reinforcing member 43 and the anti-kink protector 63 are provided, and thereby the rigidity up to the hand operation unit 5 is changed. In order to ensure safety, it is preferable that the outer periphery of the coil-shaped reinforcing member 42 or the pipe-shaped reinforcing member 43 is laminated with a skin G made of synthetic resin. That is, it is preferable to provide the coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43 inside the wall of the tube 4.
[0041]
The inner tube N is provided over the entire length of the tube 4, but a material having flexibility and strength, for example, one layer of HDPE (High Density Polyethylene) or two layers of LLDPE (Low Level Density Polyethylene) is used. .
[0042]
However, not only this, but also polyolefins such as polyvinyl chloride, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polystyrene, polyurethane, polyamide Uses various resins such as polyimide, polyoxymethylene, polyvinyl alcohol, polytetrafluoroethylene, polyvinylidene fluoride, and other fluorine-based resins, thermoplastic elastomers such as polyamide elastomers and polyester elastomers, and various rubbers such as silicone rubber and latex rubber. it can.
[0043]
As described above, the tube 4 has a proximal end portion on the side of the hand operation unit 5, a tube layer made of the material forming the inner tube N, a coiled reinforcing member layer made of the coiled reinforcing member 42, and a pipe-shaped reinforcing member. 43, the intermediate portion is composed of two layers of the tube layer and the coil-shaped reinforcement member layer, and the tip portion is composed of only the tube layer. Therefore, the outer diameter becomes narrower from the base end toward the tip end, so that the deep portion can be easily reached and the operability is improved.
[0044]
In addition, since the flexible guide member 2 is provided at the distal end of the distal end portion composed of only the tube layer, the operability when advancing in the lumen is also improved.
[0045]
In particular, the tube 4 has at least one lumen n, a drive shaft S is inserted into the lumen n, and an ultrasonic vibrator 33 is provided at the tip of the drive shaft S. Is located at the distal end consisting of only the tube layer, so that the distal end of this tube layer alone serves as an ultrasonic window, so that the transmission and reception of ultrasonic waves are performed smoothly, and the accuracy or operability of ultrasonic diagnosis is improved. become.
[0046]
Further, a lubricating layer made of a hydrophilic polymer substance having lubricity in a wet state may be formed on the outer surface of the distal end side of the catheter 1 so that the catheter 1 can be smoothly inserted into the lumen. The lubricating layer made of a hydrophilic polymer substance is preferably provided on the distal end side of the catheter 1, near the guide member 2, the probe section 3, and near the center of the tube 4 (near the distal end of the pipe-shaped reinforcing member 43). desirable. If high lubricity is imparted to the entire catheter 1, the hand to be operated at the time of insertion into a lumen becomes slippery and handling becomes difficult. Further, it is desirable to provide a lubricating layer made of silicone or the like having a certain degree of lubricating property on the base end side where the lubricating layer made of a hydrophilic polymer substance is not provided, although the lubricating property is lower than that of the hydrophilic polymer substance. .
[0047]
Since the coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43 reinforce the inner tube N, they are preferably rigid, for example, made of metal. However, the coil-shaped reinforcing member 42 is configured so that the pitch of the coil is slightly increased, the rigidity is gradually increased from the flexible inner tube N, and the kink resistance is improved. It is preferable to use a metal pipe having greater rigidity than the reinforcing member 42.
[0048]
Stainless steel, superelastic alloy, or the like is used as a metal material for forming the coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43. As the superelastic alloy, for example, a Ni-Ti alloy is preferably used.
[0049]
FIG. 4 is a diagram illustrating the structure of the pipe-shaped reinforcing member. As shown in FIG. 4, the pipe-shaped reinforcing member 43 forms a stiffness weakening portion Y in a predetermined region L from the distal end portion to the anti-kink protector 63, and gradually changes the stiffness of the pipe-shaped reinforcing member 43. I have. As the rigidity weakening portion Y, any shape may be used, but a spiral slit 44 is preferable in consideration of ease of manufacture.
[0050]
If the spiral slits 44 are formed in the pipe-shaped reinforcing member 43 made of a straight metal pipe as described above, a sudden change in rigidity at a connection portion between the coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43 is reduced. The rigidity gradually changes with the addition of the coil-shaped reinforcing member 42 and the addition of the pipe-shaped reinforcing member 43 from the single layer of the inner tube N, and the bending and breakage of the tube 4 can be further prevented or suppressed. 2 can improve kink resistance and breakage resistance.
[0051]
However, if the spiral slit 44 is formed over the entire length of the pipe-shaped reinforcing member 43, the rigidity of the pipe-shaped reinforcing member 43 itself is reduced. It is preferable to terminate at a position halfway to the point, preferably within a position within 100 mm from the tip of the pipe-shaped reinforcing member 43.
[0052]
When a spiral slit 44 having a constant width is formed, the pitch may be uniform, but as shown in FIG. 4, the pitch gradually increases from the distal end to the proximal end of the pipe-shaped reinforcing member 43. When this is changed, the rigidity of the pipe-shaped reinforcing member 43 itself gradually changes from the distal end side to the base end side, which is more preferable.
[0053]
The coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43 may be separate bodies, but the surgeon may perform an operation of twisting and rotating the entire operation section 5 at hand. In such a case, since the torsional torque must be reliably transmitted to the inner pipe N, it is desirable that the coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43 be connected to each other.
[0054]
FIG. 5 is a sectional view taken along line 5-5 in FIG. As shown in FIG. 5, when the joint connection between the two is performed at or near the terminal end of the spiral slit 44, the torque transmitted to at least the rigid portion where no slit is formed can be reliably applied to the coiled reinforcing member. 42.
[0055]
The joining is preferably performed by forming one or more through holes 45 in the pipe-shaped reinforcing member 43 and filling the through holes 45 with a filler 46 such as an adhesive. In this way, not only is the joining workability good, but also unnecessary ones, for example, ones in which the burrs do not protrude outward in the radial direction and have a high degree of use safety can be obtained. In FIG. 5, two through holes 45 are provided at symmetric positions with respect to the axis of the catheter 1.
[0056]
FIG. 6 is a cross-sectional view showing the coil-shaped reinforcing member in the pipe-shaped reinforcing member. In the guide member 2, the brazing portions 23a and 23b are provided to adjust the elasticity. Alternatively, as shown in FIG. 6, a brazing portion 42a (indicated by a broken-line hatch) may be provided at a predetermined position of the coil-shaped reinforcing member 42.
[0057]
FIG. 7 is a diagram showing a hand operation unit and an external unit. As shown in FIG. 7, the hand operation unit 5 has a main body 50 at the center corresponding to the rigid holding member H described above. On the right side of the main body 50, a joint 51 connected to the right end of the main body 50, and a connector 52 connected to a connector 72 of the external unit 7 described later and configured to transmit a signal from the signal line 55, , A rotor 53 supported between the main body 50 and the joint 51 so as to be rotated by a rotational force from the external unit 7 and rotated together with the connector 52, and an inner space of the main body 50 connected to the rotor 53 And a connection pipe 54 that is provided so as to pass through 50a.
[0058]
On the other hand, an inlet pipe 57 connected to a luer hub 56 into which an ultrasonic transmission liquid such as a physiological saline solution is injected from a pressure-resistant tube T is provided at a central portion of the main body 50, and a check valve for preventing a backflow of the ultrasonic transmission liquid. A valve 58, a flow path 59 through which a physiological saline solution flows, a seal plate 60 for sealing between the flow path 59 and the decompression chamber 50b, and a seal member 61 composed of an O-ring O (two locations before and after the decompression chamber 50b) And are provided.
[0059]
Note that, in the flow path 59, the inner pipe N is not provided on the outer periphery of the drive shaft S, so that the ultrasonic transmission liquid injected into the flow path 59 from the inlet pipe 57 flows into the inner pipe N. Will be introduced.
[0060]
The ultrasonic transmission liquid introduced into the inner tube N passes through the inside of the lumen n of the inner tube N, fills around the ultrasonic vibrator 33, and forms a priming flow path provided in the housing 32 and the reinforcing tube 24. R ₁ , R ₂ (See FIG. 2).
[0061]
On the left side of the main body 50, a kink-resistant protector 63 is tightly connected to the tapered end of the main body 50. The kink-resistant protector 63 has a passage 62 in which the tube 4 is inserted. The pipe-shaped reinforcing member 63 and the pipe-shaped reinforcing member 43 are provided so that the kink-resistant property can be exhibited. The material or the shape is adjusted by a material having an intermediate hardness between the hardness of 43 and the hardness of the main body 50.
[0062]
In FIG. 7, reference numeral "64" denotes a waterproof cover, and reference numeral "65" denotes a through hole for depressurizing the decompression chamber.
[0063]
The external unit 7 transmits the rotational force of the motor M, which is a rotational drive source, to the drive shaft S via the rotary shaft 71 and the connectors 72 and 52, and outputs an electric signal from the ultrasonic transducer 33 to a signal line. The signal is transmitted to the ultrasonic diagnostic apparatus 74 via the rotary shaft 71 and the rotary connector 73, subjected to appropriate processing in the ultrasonic diagnostic apparatus 74, and displayed on a monitor or the like. Avoid statements.
[0064]
Next, the operation of the present embodiment will be described.
[0065]
First, the surgeon connects the connectors 52 and 72 to electrically and mechanically connect the hand operation unit 5 and the external unit 7. On the other hand, the ultrasonic transmission liquid is filled into the inner pipe N from the inlet pipe 57 of the hand operation unit 5. Whether the filling of the ultrasonic transmission liquid is completed is determined by the priming flow path R of the reinforcing tube 24. ₂ It can be determined by whether or not the ultrasonic transmission liquid has been discharged to the outside.
[0066]
In this state, the operator holds the hand operation unit 5 and inserts the catheter 1 into the lumen. X-ray irradiation is performed from the start of this insertion, and the position of the catheter 1 in the living body is confirmed while observing the position of the distal-side coil-shaped member 22a that is radiopaque.
[0067]
When the probe section 3 of the catheter 1 reaches a predetermined position in the lumen, the external unit 7 operates. When the motor M rotates, the rotational force is transmitted to the drive shaft S via the rotating shaft 71 and the connectors 72 and 52, and the electric signal from the ultrasonic diagnostic apparatus 74 is transmitted via the rotary connector 73 and the signal line 55. And transmitted to the ultrasonic vibrator 33.
[0068]
Therefore, the ultrasonic transducer 33 emits an ultrasonic wave while rotating in the tube 4, reaches the affected part via the ultrasonic transmission liquid, and is reflected. The reflected wave is received by the ultrasonic transducer 33. Is transmitted to the ultrasonic diagnostic apparatus 74 via the signal line 55. The ultrasonic diagnostic device 74 appropriately processes the signal internally, converts the signal into a video signal, and displays the video signal on a monitor screen.
[0069]
At the time of such observation or diagnosis, in order to observe or diagnose other parts or the like, the hand operation unit 5 or the base end of the tube 4 is often operated to displace or twist the catheter 1 in the direction perpendicular to the axis. There is a case where an addition operation is performed.
[0070]
At the time of such an operation, the long and flexible catheter 1 is bent at a portion where the soft tube 4 is connected to the main body 50 which is a hard portion, or at a point where the physical properties of the tube 4, the probe portion 3 and the guide member 2 change. It may be twisted or twisted.
[0071]
However, in the present embodiment, the pipe-like reinforcing member 43 is provided at the tip of the anti-kink protector 63 of the hand operation unit 5, the spiral slit 44 is provided at the tip of the pipe-like reinforcing member 43, and the pipe-like reinforcing member 43 is further provided. Since the coil-shaped reinforcing members 42 are provided between the inner tube N and the inner tube N, the rigidity gradually changes from the flexible inner tube N to the rigid main body 50 of the hand operation unit 5. The strength with respect to the acting external force does not change significantly but changes gradually.
[0072]
Therefore, even if the catheter 1 is displaced or twisted in the direction perpendicular to the axis, bending or breakage of the tube 4 at this connection portion is prevented or suppressed, and the tube 4 does not kink, and breakage does not occur.
[0073]
In particular, since the spiral slits 44 of the pipe-shaped reinforcing member 43 gradually increase the interval from the distal end to the proximal end, the rigidity of the pipe-shaped reinforcing member 43 itself gradually increases from the distal end to the proximal end. And the tube 4 is supported so as not to be bent, and as a result, the tube 4 is prevented from being damaged.
[0074]
Further, when the operator performs an operation of twisting and rotating the entire catheter 1 from the hand side, the coil-shaped reinforcing member 42 and the pipe-shaped reinforcing member 43 are joined and connected to each other. Is transmitted to the inner tube N.
[0075]
The present invention is not limited to only the above-described embodiments, and various modifications can be made by those skilled in the art within the technical concept of the present invention. For example, the catheter has a single lumen n, but may have a plurality of lumens. The catheter may use not only ultrasound but also other catheters such as optical coherence tomography (OCT). It can also be applied to the diagnostic catheters described above.
[0076]
Further, the rigidity weakening portion Y in the above-described embodiment is a spiral slit, but may have any shape as long as it can reduce the rigidity.
[0077]
【The invention's effect】
As described above, according to the first aspect of the present invention, when the proximal end side of the flexible tube of the catheter is held by the holding member, the coil-shaped reinforcing member is provided inside the tube near the holding member, and this is connected to the pipe shape. Since the catheter is covered with the reinforcing member, even if the catheter is displaced or twisted in the direction perpendicular to the axis, bending and breakage of the tube near the holding member are prevented and suppressed, and the kink resistance and breakage resistance of the tube are improved.
[0078]
According to the invention of claim 2, since the rigidity weakening portion is provided in a predetermined region from the distal end portion of the pipe-shaped reinforcing member, the change in strength at the connecting portion is reduced, and the rigidity of the pipe-shaped reinforcing member is gradually changed. The kink resistance and breakage resistance of the tube can be improved.
[0079]
According to the third aspect of the invention, since the rigidity weakening portion is formed by the spiral slit, it is possible to easily change the strength at the connecting portion, which is advantageous in terms of manufacturing.
[0080]
According to the invention of claim 4, since the interval between the spiral slits is gradually widened from the distal end side to the proximal end side, the effect of the preceding aspect is further improved.
[0081]
According to the fifth aspect of the present invention, since the spiral slit is formed from the tip of the pipe-shaped reinforcing member to the middle of the holding member, the base has a high rigidity and the tip is a flexible pipe-shaped reinforcing member.
[0082]
According to the sixth aspect of the present invention, since the coil-shaped reinforcing member and the pipe-shaped reinforcing member are joined at the end of the spiral slit on the holding member side, the torsional torque can be transmitted reliably.
[0083]
According to the seventh aspect of the present invention, the through hole is formed in the pipe-like reinforcing member, and the coil-like reinforcing member and the pipe-like reinforcing member are joined by filling the through-hole with a filler. It does not protrude and can be obtained with high safety.
[0084]
In the invention of claim 8, the base end of the tube is formed from three layers of the tube layer, the coil-shaped reinforcing member layer, and the pipe-shaped reinforcing member layer, and the middle portion is formed from the two layers of the tube layer and the coil-shaped reinforcing member layer. Since the portion is composed only of the tube layer, the outer diameter becomes thinner toward the tip, and the reach to the deep portion is improved.
[0085]
According to the ninth aspect of the present invention, since a more flexible guide member is provided at the distal end of the distal end portion composed of only the tube layer, the operability when advancing in the lumen is improved.
[0086]
In the invention according to claim 10, the tube has at least one lumen, a drive shaft is inserted into the lumen, an ultrasonic vibrator is provided at a tip of the drive shaft, and the ultrasonic vibrator is a tube. Since it is located at the distal end composed of only the layer, the distal end of only the tube layer serves as an ultrasonic window, and the accuracy or operability of ultrasonic diagnosis is improved.
[Brief description of the drawings]
FIG. 1 is a schematic front view showing an embodiment of the present invention.
FIG. 2 is a sectional view showing a distal end portion of the tube of the embodiment.
FIG. 3 is a sectional view showing a proximal end portion of a tube.
FIG. 4 is a diagram illustrating a structure of a pipe-shaped reinforcing member.
FIG. 5 is a sectional view taken along line 5-5 in FIG. 4;
FIG. 6 is a cross-sectional view showing a coil-shaped reinforcing member in a pipe-shaped reinforcing member.
FIG. 7 is a diagram showing a hand operation unit and an external unit.
[Explanation of symbols]
1. Ultrasonic catheter,
2. Guide member,
33 ... Ultrasonic vibrator
4 ... tube,
42 ... Coil-shaped reinforcing member,
43 ... pipe-shaped reinforcing member,
44 ... helical slit,
45 ... through hole,
46 ... filler,
H: holding member,
n ... lumen,
S: drive shaft,
Y: Rigidity weakened part.

Claims (10)

A catheter in which a proximal end side of a flexible tube is held by a holding member, wherein the tube near the holding member has a coiled reinforcing member inside the tube wall, and the base end of the coiled reinforcing member. A catheter covered on its side with a pipe-shaped reinforcing member, and the pipe-shaped reinforcing member is held by the holding member. The catheter according to claim 1, wherein the pipe-shaped reinforcing member has a rigidity weakening portion provided in a predetermined region from a distal end portion to a proximal end side. The catheter according to claim 2, wherein the rigidity weakening portion is a spiral slit. The said spiral-shaped slit has a fixed width | variety, The space | interval between them was made to gradually widen from the front-end | tip side of the said pipe-shaped reinforcement member to the base end side, The Claim 3 characterized by the above-mentioned. The catheter as described. 5. The catheter according to claim 3, wherein the spiral slit is formed from a tip of the pipe-shaped reinforcing member to a middle of the holding member. 6. The catheter according to any one of claims 3 to 5, wherein the coil-shaped reinforcing member and the pipe-shaped reinforcing member are joined at or near the terminal end of the spiral slit on the holding member side. 7. The catheter according to claim 6, wherein the joining forms a through-hole in the pipe-shaped reinforcing member, and the through-hole is filled with a filler. The tube has a base end composed of three layers of a tube layer, a coil-shaped reinforcement member layer, and a pipe-shaped reinforcement member layer, an intermediate part composed of two layers of the tube layer and the coil-shaped reinforcement member layer, and only the tube layer. The catheter according to any one of claims 1 to 7, further comprising a distal end portion made of: The catheter according to claim 8, further comprising a guide member at a distal end of the distal end portion composed of only the tube layer. The tube has at least one lumen, further includes a drive shaft inserted into the lumen, and an ultrasonic vibrator provided at a tip of the drive shaft, the ultrasonic vibrator includes: The catheter according to claim 8, wherein the catheter is located at a distal end portion composed of only the tube layer.

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