JP4198214B2 - Guide wire - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a guide wire, and more particularly to a guide wire suitably used in a medical technology system for treating intestinal obstruction.
[0002]
[Prior art]
A guide wire is widely used in the medical field as a device for guiding a tube such as a catheter to a target site in a body cavity. Conventionally, guide wires in which a metal core material is encapsulated with a coil spring and guide wires in which a metal core material is coated with a synthetic resin are known, and the tip portions of these guide wires are linear. (Straight) and J-shaped. In recent years, in the medical field for treating intestinal obstruction, a technique has been developed in which a treatment tube (ileus tube) is inserted from the oral / nasal cavity into the digestive tract and the intestinal obstruction site is expanded with a balloon. These guide wires are also used to guide the blood to the digestive tract.
[0003]
[Problems to be solved by the invention]
If a straight or J-shaped guide wire used in the past is used, when the tube forms a loop in the digestive tract, the distal end of the guide wire from the side hole for suction of gastric juice or the like formed on the side wall of the tube Jumps out and it becomes difficult to advance the guide wire, and the tube cannot be guided thereafter. FIG. 5 shows a state where the distal end protrudes from the side hole 101 of the treatment tube 100 which is curved in a loop shape in the stomach 60 in the conventional guide wire 50 having a straight distal end. As shown in FIG. 5, the distal end of the straight-shaped guide wire 50 advances along the outside of the loop of the inner wall of the treatment tube 100, so that when the side hole 101 exists outside the loop, it tends to fit into the side hole 101.
[0004]
In addition, when using a relatively strong coil spring type guide wire, in order to improve the operability in the tube, olive oil may be applied to the surface of the guide wire to obtain lubricity. When the tube forms a loop, the medical practice is severely restricted, such as the tip of the guide wire popping out from the suction side hole of the tube, making it difficult to remove the guide wire from the tube, and making it difficult to reinsert. It was.
[0005]
An object of the present invention is to provide a guide wire having a structure in which a distal end of a guide wire is difficult to enter a side hole of a treatment tube in medical practice for treating intestinal obstruction.
[0006]
[Means for Solving the Problems]
Such an object is achieved by the following inventions (1) to (6).
[0007]
(1) It is inserted into a tube having a side hole, and has a substantially linear base end portion and a substantially linear tip end portion. an intermediate portion which is pre-formed in a curved shape, the height of the intermediate portion is slightly larger than the inner diameter of the tube to be inserted, and a state in which the bending has been spread in the intermediate portion by the tube wall of the tube The guide wire is characterized in that the distal end portion is at an angle from the tube wall toward the tube center portion, and the leading edge is configured to keep a state in which the tip portion does not contact the tube wall in advance.
[0008]
(2) The guide wire according to (1), wherein a transition portion between the distal end portion and the intermediate portion exists on or near an extension of the axis of the linear base end portion.
[0009]
(3) The guide wire according to (2), wherein the distal end portion is substantially parallel to the linear base end portion and is present on or near the extension of the shaft of the base end portion.
[0010]
(4) The guide wire according to any one of (1) to (3), wherein the intermediate portion has a multi-curved shape having at least three stages of curved portions.
[0011]
(5) The guide wire according to any one of (1) to (4), comprising a core material made of metal and a synthetic resin layer covering the core material.
[0012]
(6) The guide wire according to (5), wherein a hydrophilic lubricating layer is provided on the surface of the synthetic resin layer.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the guide wire of the present invention will be described in detail with reference to preferred embodiments shown in the accompanying drawings.
[0014]
FIG. 1 is a cross-sectional view showing a distal end portion of a guide wire according to an embodiment of the present invention. In FIG. 1, the guide wire 11 continues from the linear base end portion 4 to the distal end portion 6 via the first bending portion 1, the second bending portion 2, and the intermediate portion 5 having the third bending portion 3. ing. The first bending portion 1 and the third bending portion 3 have a curvature radius in the same direction, and the second bending portion 2 has a curvature radius in a different direction. Accordingly, the distal end portion 6 exists on the extension line 7 of the shaft of the proximal end portion 4 .
[0015]
The guide wire 11 is formed by covering a synthetic metal layer 9 on a metal cored bar 8 in which the intermediate portion 5 and the tip end portion 6 are tapered. Examples of the metal material suitably used for the core metal 8 include a superelastic alloy such as a Ni—Ti alloy, a stainless alloy, and the like. Examples of the resin material suitably used for the synthetic resin layer 9 include polyurethane resins such as polyurethane and PTFE (polytetrafluoroethylene), polyamide resins such as nylon, polyethylene, polypropylene, and polyolefin. These resins can be mixed with X-ray contrast fine powders such as barium oxide and tungsten. In addition, a coil 10 made of platinum, gold, or the like for X-ray contrast is wound around the distal end portion of the cored bar 8, thereby making it possible to perform work under X-ray fluoroscopy. It is desirable that the surface of the synthetic resin layer 9 is further coated with a hydrophilic lubricating film made of maleic anhydride or the like. Thereby, the insertion resistance in the treatment tube or the body cavity is reduced, and smooth insertion is possible. Desirably, the lubricious coating is not coated on portions that are not inserted into the body cavity.
[0016]
Although the outer diameter of such a guide wire 11 is not specifically limited, Usually, it is preferable that it is about 0.6-1.7 mm, and it is more preferable that it is about 0.9-1.3 mm. The thickness of the synthetic resin layer 9 is desirably about 0.05 to 0.15 mm in the vicinity of the base end portion 4 and about 0.15 to 0.3 mm in the vicinity of the distal end portion 6. Furthermore, the total length of the guide wire 11 is about 100 to 450 cm, preferably about 260 to 350 cm.
[0017]
Next, suitable specifications such as a multi-curved shape in the guide wire 11 of the present invention will be described with reference to FIG.
[0018]
In FIG. 2, H is the height of the intermediate portion 5, in other words, the maximum separation distance between the extension line 7 of the shaft and the intermediate portion 5. The value of H is desirably slightly larger than the inner diameter of the treatment tube, specifically, preferably 3 to 15 mm, and more preferably 6 to 10 mm.
[0019]
L1 indicates the length of the tip portion 6. L1 is preferably 3 to 15 mm, and more preferably 5 to 8 mm, considering the route selectivity of the guide wire 11.
[0020]
L2 indicates the length of the intermediate portion 5 in the guide wire axial direction. L2 is preferably 10 to 40 mm, more preferably 15 to 25 mm, considering that the force from the proximal end is transmitted to the distal end portion 6 in balance with the value of H.
[0021]
As a method for pre-molding the multi-curved shape of the guide wire 11 of the present invention, it is sufficient to anneal it after fixing it in the mold at the stage of the core metal, and anneal it at 400 to 600 degrees for about 5 minutes to 2 hours. Is preferred.
[0022]
3 and 4 are views showing a state in which the guide wire 11 of the present invention is inserted into the treatment tube 100. In FIG. 3, an intestinal obstruction treatment tube (ileus tube) 100 inserted into the stomach 60 shows a loop-like curved state as shown in the figure. The treatment tube 100 is provided with a side hole 101 for sucking gastric juice or the like. FIG. 4 is a view for explaining the operation of the guide wire distal end portion 6 and the intermediate portion 5 in FIG.
[0023]
Since the guide wire 11 of the present invention has a height H of the intermediate portion 5 slightly larger than the inner diameter of the treatment tube 100, the curve is pushed and spread by the tube wall of the treatment tube 100 as shown in FIG. . The distal end portion 6 of the guide wire 11 is preformed so as to be substantially parallel to the proximal end portion 4, but the distal end portion 6 becomes the treatment tube 100 by being in a state where the curve is expanded in this way. The leading end 12 of the guide wire 11 advances while maintaining a state of not contacting the tube wall. Therefore, even when the side hole 101 exists on the pipe line, the leading edge 12 does not jump out of the side hole 101.
[0024]
Moreover, since the guide wire 11 of the present invention has a synthetic resin coating layer and a hydrophilic lubricating film on the surface, the apex of the intermediate portion 5 and the transition portion between the intermediate portion 5 and the distal end portion 6 are tubes of the treatment tube 100. Even if it moves while in contact with the wall, there is almost no frictional resistance and it can proceed smoothly.
[0025]
The specific structure of the guide wire of the present invention is not particularly limited as long as it has the above-described characteristics, and the tube (catheter) to be applied is not particularly limited to treatment for intestinal obstruction. Various catheters used in the human body such as vascular catheters such as ding catheters and angiographic catheters, introducer sheaths, outer needles, gastric tube catheters, endotracheal tubes, endoscopic tubes, ultrasonic catheters, ureteral catheters, etc. Kind.
[0026]
【Example】
Hereinafter, specific examples of the present invention will be described in detail. A guide wire having the structure shown in FIGS. 1 and 2 was manufactured. Each condition of this guide wire is as follows.
[0027]
Total length of guide wire: 350cm
Constituent material of the core metal: Ni-Ti superelastic alloy guide wire outer diameter: 0.97 mm
Constituent material of synthetic resin layer: Constituent material of polyurethane hydrophilic lubricating film coating: Height of block polymer intermediate part 5 of dimethylacrylamide and glycidyl methacrylate H: 8 mm
Length L1 of tip 6: 7 mm
Axial length L2 of intermediate part 5: 20 mm
The degree of curvature of the second bending portion 2: When the guide wire obtained as described above corresponding to the circumference with a radius of 15 mm was inserted into the ileus tube curved in a loop shape, the tip advanced without being caught by the side hole.
[0028]
【The invention's effect】
As described above, according to the guide wire of the present invention, there is no protrusion from the suction side hole in the treatment tube, and the insertion property and the operability of the digestive tract selection are excellent, reducing the burden on the operator and the patient. It becomes possible.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of a guide wire according to the present invention.
FIG. 2 is a view for explaining the specifications of the guide wire of the present invention.
FIG. 3 is a diagram for explaining a use state of the guide wire of the present invention.
FIG. 4 is a diagram for explaining the operation of the guide wire of the present invention.
FIG. 5 is a diagram for explaining a use state of a conventional guide wire.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 1st bending part 2 2nd bending part 3 3rd bending part 4 Base end part 5 Intermediate | middle part 6 Tip part 7 Axis extension line 8 Core metal 9 Synthetic resin layer 10 Coil 11 Guide wire

Claims (6)

It is inserted into a tube having a side hole, and has a substantially linear base end portion and a substantially linear tip end portion, and has a multi-curved shape between the base end portion and the tip end portion. an intermediate portion which is preformed, the height of the intermediate portion is slightly larger than the inner diameter of the tube to be inserted, when a state in which the bending has been spread in the intermediate portion by the tube wall of the tube, The guide wire is characterized in that the tip portion is at an angle from the tube wall toward the tube center portion, and the leading end is configured not to contact the tube wall in advance.  The guide wire according to claim 1, wherein a transition portion between the distal end portion and the intermediate portion exists on or near an extension of the axis of the linear base end portion.  3. The guide wire according to claim 2, wherein the distal end portion is substantially parallel to the linear base end portion and is present on or near an extension of the shaft of the base end portion.  4. The guide wire according to claim 1, wherein the intermediate portion has a multi-curved shape having at least three stages of curved portions.  The guide wire according to claim 1, comprising a core material made of metal and a synthetic resin layer formed by coating the core material.   The intermediate portion has a first bending portion, a second bending portion, and a third bending portion from the base end portion, and the first bending portion and the third bending portion have a radius of curvature in the same direction, The guide wire according to claim 1, wherein the second bending portion has a radius of curvature in a direction different from that of the first bending portion and the third bending portion.

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