WO1993018813A1

WO1993018813A1 - Medical tube

Info

Publication number: WO1993018813A1
Application number: PCT/JP1993/000318
Authority: WO
Inventors: Keiji Igaki; Sigeru Saito
Original assignee: Keiji Igaki; Sigeru Saito
Priority date: 1992-03-19
Filing date: 1993-03-17
Publication date: 1993-09-30
Also published as: JPH11221286A; AU3766893A

Abstract

A medical tube for use for inspection, diagnosis, and treatment of a lesion occurring in a vessel. The shape of the cross section of this medical tube is flat (e.g. an oval). A medical tube having a flat shape is firm and hence has a great strength, and is superior in flexibility. Moreover, since it easily bends only in a direction of its short axis, an operation made locally by an operator can accurately be transmitted to the distal end portion. It is possible to form a plurality of interior holes in the medical tube, in which case these interior holes are arranged on the long axis of the tube.

Description

TECHNICAL FIELD The present invention relates to a medical tube used for inspection, diagnosis, treatment, and the like of a lesion generated in a blood vessel. BACKGROUND ART In recent years, in the field of medicine, in examining, diagnosing, and treating lesions that have occurred in body lumens (vessels) such as the digestive tract and blood vessels, surgical methods, that is, direct examination of lesions, have been conducted. A method of opening a medical tube and inserting the medical tube into a lumen to reach a lesion is often adopted instead of using an incision method as much as possible.

For example, various types of medical tubes are used to inject drugs into lesions, and medical tubes with a tip attached to a device such as a sieve are used to remove lesions, remove gallstones, or perform medical treatments. Observing the inside of the digestive tract and the like with an endoscope in which an image receiving optical lens and a light guiding optical fiber are housed in a tube is already a common technique.

It has been established as a treatment and diagnostic act.

Recently, such medical tubes are also used for diagnosis and treatment of the circulatory system, such as injection of a contrast medium, measurement of blood pressure, and treatment of vascular stenosis caused by accumulation of atheroma on the inner wall of a blood vessel. It has become to be. In particular, the treatment of vascular stenosis has traditionally been performed by a large-scale operation called bypass surgery, which has been difficult and difficult for the patient himself. By using this method, it is possible to perform treatment with a relatively simple operation technique with almost no injury to the human body.

For example, a method is known in which the atheroma is excised using a medical tube having a shaver attached to the tip, or the atheroma is evaporated using a medical tube containing an optical fiber for guiding laser light. . Furthermore, a method of inserting a balloon catheter with a thin balloon into a medical tube inserted into a blood vessel to reach the atheroma area, and inflating the balloon catheter to expand the stenotic vessel lumen. Proposed.

By the way, as a medical tube used in the above-mentioned examination, diagnosis, treatment, etc., it is necessary that the stiffness can be pushed in strongly (push-ability). It is necessary to be able to freely change the angle of the tip (trackability) and to be able to pass through the vessel smoothly (crossability). In particular, the above performance is strictly required when inserting into a complicatedly bent vessel such as a blood vessel.

Here, the medical tubing conventionally used generally has a circular cross-section, and in such a tube having a circular cross-section, in order to strengthen the stiffness, the tube is made thicker and the tube itself is made thicker. There is a need.

However, a tube with a circular cross section is simply made thicker, Thickness makes the body less supple and difficult to operate. In addition, smooth passage through the vessel is lost, and it is particularly difficult to pass through a narrow part having a lesion.

The passability is improved by making the tube thinner. However, if the tube is made thinner, the stiffness becomes weaker and the restoring force becomes weaker, and the pushability and trackability deteriorate.

In the case of a tube having a circular cross section as described above, it is difficult to achieve both pushability, trackability, and crossability, and satisfactory performance cannot be obtained.

Also, insert a wire mesh into the tube to improve the push aptitude, apply a coating agent around the tube, and put a guide wire ahead of the tube at the time of insertion so that the wire passes through the wire (^). Although methods such as insertion into a blood vessel have been proposed, these means are secondary and cannot improve the intrinsic performance of the tube.

Therefore, an object of the present invention is to provide a medical tube that is excellent in any of pushability, trackability 1, and crossability. DISCLOSURE OF THE INVENTION In order to achieve the above object, the medical tube of the present invention is characterized in that its cross section is flat (for example, elliptical).

Medical tubing is used for examination, diagnosis, and treatment of lesions that have occurred in vessels. It is used and inserted into a vascular vessel having a lesion, the tip reaches the lesion, and the operation at hand of the operator is transmitted to the tip to exert a medical effect.

In order to perform more accurate medical treatment with such a medical tube, it is necessary to apply a strong stiffness during insertion into the vessel, because it can be pushed in, and the operation at hand is transmitted to the distal end, and the angle of the distal end It needs to be able to change freely and to be able to pass through the vessel smoothly, that is, push ability, track ability, and cross ability.

The flat-shaped medical tubing has strong stiffness, high strength and excellent flexibility, and it can be easily bent only in the short axis direction, so that the operation at hand of the surgeon is accurately transmitted to the distal end. . In addition, it passes smoothly even in a vessel having a lesion. In other words, it has excellent pushability, trackability, and crossability.

Therefore, according to the present invention, a medical tube having a wide range of applications can be easily inserted into a complicatedly bent vessel such as a blood vessel. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an example of the medical tube of the present invention. FIG. 2 is a sectional view showing an example of the medical tube of the present invention. FIG. 3 is a cross-sectional view showing a medical tube inserted into a vessel having a lesion. FIG. 4 is a sectional view showing another example of the medical tube of the present invention. FIG. 5 is a cross-sectional view showing an example of a tube having a two-layer structure of steel and plastic.

FIG. 6 is a schematic perspective view of a main part of an example of a plastic tube with a mesh interposed therebetween, partially cut away.

FIG. 7 is a schematic perspective view of a main part showing an example of a tube having a spiral groove formed on the surface.

FIG. 8 is a schematic perspective view of a main part showing an example of a tube having fine projections formed on the surface.

FIG. 9 is a cross-sectional view showing an example of a tube having a pair of inner holes _c . FIG. 10 is a cross-sectional view showing another example of a tube having a pair of inner holes formed therein

FIG. 11 is a cross-sectional view showing an example of a tube in which a plurality of inner holes are arranged asymmetrically.

FIG. 12 is a cross-sectional view showing an example of a tear-shaped tube.

FIG. 13 is a cross-sectional view showing another example of a tube having a tear-shaped cross section.

FIG. 14 is a sectional view showing an example in which the present invention is applied to a tube of an endoscope. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, examples in which the present invention is applied to a cardiac catheter will be described.o

A cardiac catheter 1 is inserted into the atrium or ventricle of the heart, for example, from a vein or artery, and is used to test the function of the heart In this embodiment, as shown in FIGS. 1 and 2, a soft plastic tube having a flat cross section (in this embodiment, a substantially elliptical cross section) is used. It has a predetermined length and a center hole 2 having a substantially circular cross section for injecting various drugs, contrast media, and the like in the center. The tip 3 is tapered to facilitate insertion and not to damage the blood vessel.

In the heart catheter 1 having such a shape, the outer shape is elliptical, whereas the shape of the center hole is circular, so that the thickness is increased in the major axis direction of the ellipse (the X-axis direction in FIG. 2). As the part 4 is formed, the stiffness becomes stronger and the resilience is obtained, so that the above-mentioned push appeal can be secured. In addition, flexibility is obtained by setting the thin portion 5 in the short axis direction (the Y axis direction in FIG. 2). That is, since it is selectively bent in the short-axis direction (Y-axis direction), the operation at hand of the operator can be transmitted to the distal end portion 3 by controlling the insertion direction, and the track ability and the cross ability can be transmitted. Can also be secured o

Further, as shown in FIG. 3, the blood vessel 31 having the lesion 32 usually has a luminal cross-sectional shape close to a flat shape. Therefore, it is difficult to insert a tube with a perfectly circular cross section.However, the heart catheter 1 with a flat cross section must be operated so that the short-axis direction is the narrowest part of the blood vessel 31. Thereby, it can be smoothly inserted into the blood vessel 31 having such a lesion 32.

In the heart catheter 1, as shown in FIG. 4, a hole 41 such as a lead hole through which an air hole or a lead wire passes is used depending on the application, and a thick portion in the X-axis direction is formed. 4 may be formed. In this case, the hole By arranging 4 1 on the long axis centering on the center hole 2, the operation at hand of the surgeon can be evenly transmitted to the entire tube, and operability is improved.

In order to supply a contrast agent to, for example, the heart using such a heart catheter 1, the heart catheter 1 is introduced through a blood vessel, for example, at the Sookee part or the elbow part. At this time, the heart catheter 1 smoothly passes through the blood vessel and easily reaches the heart by the operation at hand of the operator. Then, when it reaches the heart, a contrast medium is injected into a medical tube. As a result, the contrast agent is supplied to the target part of the heart.

The embodiments to which the present invention is applied have been described above. However, the present invention is not limited to the above-described cardiac catheters, and various medical tubes such as a drug injection catheter, a catheter with an electrode, a balloon catheter, an endoscope tube, and the like. Can be applied to the Alternatively, the present invention may be applied to a vasodilator, a puncture needle, an indwelling needle, and the like.

In this case, as the material of the tube, besides polymer materials such as urethane resin, vinyl chloride, nylon, polypropylene, and silicon resin, metals such as stainless steel and titanium, and shape memory alloys can be used. It is also possible to use wire mesh materials, various reinforcing wires, plastics reinforced with wire mesh materials, and the like.

When the tube is made of a plastic material or the like, the inner peripheral side and the outer peripheral side can be made of different materials. For example, it is possible to have a two-layer structure of an inner layer made of urethane and an outer layer made of nylon. Alternatively, a hard material (such as a wire mesh or a mesh made of another material) may be provided on the inside and / or outside of the tube made of soft plastic. Figs. 5 and 6 show examples of a tube in which the tube is formed by combining a plastic material and another material. Fig. 5 shows a steel material 52 on the inner peripheral side and a plastic material layer 5 on the outer peripheral side W. 3 shows a tube 51 constituted by 3. In FIG. 6, the tube 54 has a two-layer structure of an inner plastic layer 55 and an outer plastic layer 56, and a mesh material 57 is sandwiched between them. In any case, it is possible to secure sufficient strength and flexibility in the short axis direction.

The above-mentioned tube may be subjected to some surface treatment depending on the application. Examples of surface treatment include coating of a substance having an anticoagulant effect such as heparin or a substance having an antibacterial effect, chemical surface treatment such as chemical bonding of these materials by covalent bonding, etc. Physical surface treatment for forming scratches, irregularities, grooves, spiral grooves, spiral convexes, minute projections, and the like.

For example, FIG. 7 shows an example in which a spiral groove 59 is formed on the surface of a tube 58, and FIG. 8 shows an example in which a so-called wart-like minute protrusion 61 is formed on the surface of the tube 60.

In addition, it is possible to add and mix a contrast agent to the material constituting the above-described tube, and to operate while observing the behavior of the tube by X-ray fluoroscopy or the like. It can be used.

The cross-sectional shape of the medical tube of the present invention may be any shape as long as it is a flat shape, but is generally an elliptical shape as described in the previous embodiment. However, in this case, an ellipse does not mean only an ellipse in the strict sense of having two focal points, but rather a minor axis diameter and a major axis. All of the different diameters are included.

At this time, it is preferable that the ratio of the short axis diameter to the long axis diameter is 10: 1 1 to 10:40. A tube with a circular cross section may bend in any direction when the tube is pushed in, but a flat tube with the above-mentioned axial ratio has two short axis directions when the tube is pushed in. If you push it while twisting it at hand, you will proceed smoothly inside a complicated shaped vessel.

The above-mentioned tube having a flat cross section can be easily formed by, for example, forming the die into a flat shape (for example, an elliptical shape) in extrusion molding.

Further, the shape of the tube is not limited to a shape in which the peripheral surface is smoothly continuous (for example, the elliptical shape), and may be a so-called tear shape in which one end on the long axis is formed at an acute angle.

The above-mentioned tube may be provided with various holes such as a hole for guiding water and air for various treatments, in addition to a hole for supplying medicine, a hole for passing water, air, various gases, and light. It is possible.

9 to 14 show cross-sectional shapes of typical tubes to which the present invention is applied.

FIG. 9 shows an example of a tube 71 provided with two inner holes 72 and 73 having substantially equal opening diameters. By providing the two inner holes 72 and 73 in this way, it becomes possible to supply two types of chemical solutions in parallel without difficulty.

FIG. 10 shows an improved example of the tube shown in FIG. 9. However, when two inner holes 72 and 73 are provided, it is also possible to make the center part concave. Fig. 11 shows a case where the main inner hole 82 is moved to one end on the long axis, and the other inner holes 83, 84 are arranged at the end on the long axis opposite to the inner hole 82. It is. The tube 81 of this example is also one in which a plurality of inner holes are arranged on the long axis, but unlike the previous embodiment, it is not bilaterally symmetric. FIGS. 12 and 13 show an example of a tube having a so-called tear-shaped cross-sectional shape, and FIG. 12 shows a tube 91 provided with only an inner hole 92 for supplying a chemical solution at a central portion thereof. FIG. 13 shows an example in which an inner hole 93 for a plan or a treatment is provided in addition to the inner hole 92.

FIG. 14 shows an example in which the tube of the present invention is applied to an endoscope. In the tube 101 of this endoscope, the objective lens 102, the light guides 103, 104, the air supply / water supply ports 105, and the suction along the long axis when viewed in cross section · Forceps ports 106 are arranged.

The various inner holes provided in the medical tube of the present invention do not necessarily need to be formed along the longitudinal direction of the tube from the beginning to the end of the tube. It may face the outer peripheral surface of. Further, various inner holes may be branched so that a part of the inner holes is opened to the outer peripheral surface of the tube.

The medical tube of the present invention may have a flat cross section from the beginning to the end, but also includes a tube in which only a part of the tube has a flat cross section.

For example, the distal end side may have a flat cross-sectional shape, and the rearwardly continuous portion may have a circular cross-sectional shape. Conversely, the distal end may have a circular cross section, and the portion operated by hand may have a flat cross section. Further, the configuration may be such that the flat cross section and the circular cross section are alternately repeated. In addition, the tube of the present invention can have a change in thickness, for example, by gradually narrowing the tip and making the other portions thicker than this. It is also possible to combine such changes in thickness. The material of the tube may be uniform from the beginning to the end, or the material of the tube may be changed in the middle.

Claims

m Range of request

I. A medical tube characterized by having a flat portion whose cross-sectional shape is a flat shape having a different minor axis diameter and major axis diameter.

2. The medical tube according to claim 1, wherein the medical tube has flexibility in a short axis direction.

3. The medical tube according to claim 1, wherein the ratio of the minor axis diameter to the major axis diameter is 10:11 to 10:40.

4. The medical tube according to claim 1, wherein inner holes are arranged along a long axis.

5. The medical tube according to claim 1, wherein the inner holes are arranged symmetrically.

6. The medical tube according to claim 1, wherein the outer peripheral surface is subjected to a chemical surface treatment or a physical surface treatment.

7. The medical tube according to claim 6, wherein irregularities are formed on an outer peripheral surface.

8. The medical tube according to claim 7, wherein the unevenness is a spiral groove or a minute projection.

9. The medical tube according to claim 1, wherein at least one of a plastic material, a metal, and a wire mesh material is formed as a constituent material.

10. The medical tube according to claim 9, wherein a contrast agent is mixed in the constituent material.

2. The medical tube according to claim 1, wherein the outer diameter is different in a longitudinal direction.