JP2002035137A - Fluid reflux needle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid reflux needle being a hollow puncture needle for reflux a medium into the needle pipe in order to cool or warm the surface of a needle pipe, having necessary and sufficient cooling or warming effect and reduced in the invasiveness to the body by making the outer diameter of the needle pipe as possible as fine. SOLUTION: The gap between the inner and outer pipes of a double pipe comprising hollow metal pipes arranged in a concentrically circular state is axially separated into at least two parts by a separation means and one of the partitioned gaps is set to a fluid supply route (forward channel) and the other one of them is set to a fluid discharge route (return channel) and both routes are allowed to communicate with each other at the leading end parts thereof to constitute the needle pipe for refluxing a fluid. The fluid reflux pipe is constituted of this needle pipe, the needle base for fixing the needle pipe at the end part on the base side of the needle pipe, and the fluid supply tube and fluid discharge tube connected to the needle base to allow the fluid supply route and the fluid discharge route to communicate with each other to supply the fluid to the reflux route from the outside and to discharge the fluid to the outside from the reflux route.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a puncture device used by inserting it into a human body, and more particularly to a fluid recirculation needle for cooling or heating a surface of a needle tube and for returning a cooling or heating medium to the inside of the needle tube.

[0002]

2. Description of the Related Art As a preferred medical technique to which the present invention is applied, for example, PMCT (Percutaneous M)
microwave Coagulation Thera
py: percutaneous microwave coagulation therapy). This is a technique of puncturing an electrode in abnormal tissue and cauterizing and coagulating with microwaves to necrosis the abnormal tissue.However, this kind of procedure is usually difficult to puncture the human body with a thin electrode, In order to prevent heating damage due to direct contact of healthy tissue in the electrode puncture path with the electrode, a guide needle having an inner diameter larger than that of the electrode is punctured in advance to just before the target portion, and the electrode is passed through the lumen of the guide needle. Is punctured at the target site to perform the treatment. However, when used for a long period of time, even if a guide needle is used, the heat insulation of the electrode is insufficient, and the tissue to be coagulated is only the tip, whereas the entire electrode is heated and the guide needle gradually becomes There is a problem in that the temperature rises and, as a result, adversely affects healthy tissues in contact with the puncture path of the guide needle.

[0003] On the other hand, due to a similar problem, there is an applicator for thermal treatment that heats an affected part and simultaneously cools a surface of a path of an insertion part. This is to radiate high-frequency electromagnetic waves to the affected part of the living tissue, perform thermal treatment, and circulate the cooling liquid inside the applicator to cool the path surface,
Generally, the cooling reflux path is configured as a double pipe. That is, 2
The gap between the heavy pipes serves as one of the cooling water supply line (outgoing path) or drainage line (returning path), and the gap between the electromagnetic wave radiating part located at the center and the inner pipe serves as the other path, connecting both paths at the tip. Then, a recirculation passage is formed to cool.

[0004]

However, since the above-mentioned applicator is adapted only for thermal treatment, the center of the applicator is an electromagnetic wave radiating portion and naturally has a solid structure, while the present invention is applied. Needle tube to insert the electrode into the lumen of the inner tube, or to apply a technique such as injecting a drug, the center, that is, the inner tube must have a hollow structure, the inner diameter of the inner tube If a double pipe structure that becomes a fluid recirculation path is formed further outside, there is a problem that the outer diameter of the entire needle tube becomes large, and in order to avoid this, if the outer diameter is made small and the gap between the needle tubes is made small, There is a problem that the cooling or heating effect is reduced. The problem of the outer diameter of the needle tube can be similarly applied to an applicator for thermal treatment. However, in addition to the above-described structure, the applicator is usually used in a tubular tissue of a human body (for example,
This device is used by inserting it into the urethra) and does not pose a serious problem as compared with a device punctured through the epidermis of the human body to which the present invention is applied. Furthermore, the applicator for hyperthermia treatment is intended for insertion into tubular tissue as described above, and is generally made of resin to avoid tissue damage. Therefore, various types of cooling structures have been proposed, but the needle tube of the present invention is required to be made of metal in order to apply puncture from the body surface. It is difficult to make the same structure as
They are not the same comparison.

In view of the above-mentioned problems, the present invention relates to a hollow needle which is used by puncturing it through a human body epidermis, has a necessary and sufficient cooling or heating effect, and invades the human body with the outer diameter of the needle tube being as small as possible. An object of the present invention is to provide a fluid recirculation needle having a small property.

[0006]

Means for Solving the Problems A fluid recirculation needle according to the present invention comprises a double pipe composed of hollow metal pipes arranged concentrically, a gap between an inner pipe and an outer pipe (that is, an outer surface of the inner pipe and an inner face of the outer pipe). Is separated by at least two separating means in the axial direction, and one of the separated gaps is used as a fluid supply route (outgoing route), the other is used as a fluid discharging route (returning route), and both routes are provided at the tip. A needle tube configured to allow the fluid to recirculate, a needle base fixing the needle tube at a proximal end, and an external pipe connected to the needle base and communicating with the fluid supply route and the fluid discharge route, respectively. A fluid supply tube and a fluid discharge tube for supplying and discharging fluid to and from each return route of the needle tube. Of course, at the tip of the needle tube, the gap between the inner tube and the outer tube is closed so that there is no leakage of fluid, and the supply route and discharge route inside the needle base are isolated so that there is no mixing of fluid.

As the separating means, two hoop materials (metallic thin plates) are provided in parallel at the position where the gap between the inner tube and the outer tube is symmetrical in parallel with the axial direction of the needle tube.

Further, as another separating means, two thin metal wires are provided in parallel at a position where the gap between the inner tube and the outer tube is symmetrical in parallel with the axial direction of the needle tube.

[0009]

According to the fluid return needle of this means, for example, PMC
As a guide needle during the procedure of T, performing the procedure while circulating the cooling water to the return path, preventing the heat generated by the electrodes from being transmitted to the tissue in the puncture path that comes into contact with the guide needle, and only the target site. Can be cauterized effectively. In addition, the outer diameter is made smaller by circulating the fluid through one gap of the double needle as compared with a means of applying an applicator for thermal treatment in which the forward path and the return path of the return path are each formed as a gap between different pipes. Diameter.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a guide needle for PMCT suitable as an embodiment of the fluid recirculation needle of the present invention will be described in detail with reference to the drawings and two embodiments. In addition, the fluid recirculation needle of the present invention is not limited to the PMCT or another guide needle, or a recirculation needle for cooling, but a puncture needle used for a procedure while piercing the human body to heat or cool. Applicable.

FIG. 1 is an overall configuration diagram of a puncture needle used for PMCT. Reference numeral 10 denotes a guide needle outer needle of the present invention, reference numeral 20 denotes a guide needle inner needle, and reference numeral 30 denotes an electrode. The guide needle outer needle 10 has a hollow stainless steel outer tube 11 and an inner tube 12 formed as a double tube on a concentric circle, a tip of the inner tube protruding from the outer tube 11 and a cutting edge 121 provided diagonally. Tapered shape 111
Laser welding is performed near the tip of the inner tube so as to close the end, while the base end is adhered to the needle base 2, and cooling water is supplied to the needle base 2 from the outside to the needle tube return route, or The supply tube 3 and the discharge tube 4 for draining are provided so as to communicate with the return route of each needle tube. The guide needle inner needle 20 is a stainless wire 21 having a length adapted to the inner diameter of the guide needle outer needle 10 and an outer diameter, and a distal end portion is provided with an oblique cutting edge 23 that matches the cutting edge 121 of the outer needle 10, and a base portion is provided. When the guide needle is pierced into a human body, the guide needle is set on the outer needle 10 and inserted into the human body to prevent tissue from entering the lumen of the guide needle. When the puncture to the site is completed, the puncture is removed leaving the outer needle 10. The electrode 30 is inserted into the inner space of the guide needle outer needle 10 after the removal of the inner needle 20 to protrude the distal end from the distal end of the guide needle, and punctures abnormal tissue to perform treatment by microwave. The entire structure is basically constituted by 31 and the base 32.

FIG. 2 is a sectional view taken along the line A--A of a guide needle outer needle used for the PMCT of the present invention, in which a hoop material is used as a separating means, and an outer pipe for explaining means for attaching the separating means. FIG. 4 is a cross-sectional view taken along the line A-A of a state where a hoop material is attached to the inner pipe before setting the inner pipe. In the gap between the hollow inner pipe 12 and the outer pipe 11 arranged concentrically, a thin metal plate-shaped hoop member 13a2 that partitions the gap in the axial direction of the needle tube 1
A plurality of sheets are provided in parallel at symmetrical positions facing each other with the inner tube 12 interposed therebetween, and a gap divided into four sections of two large and small cross sections by the hoop material 13a is formed into a supply tube 3 and a discharge tube 4 described later. Depending on the opening position of the hole 18 provided in the outer needle 11 to allow the supply route 14 and the discharge route 15 to communicate with each other, whether one side having a large cross-sectional area is the cooling water supply route 14 and the other side is the discharge route 15 Or two adjacent large and small gaps as the supply route 14,
The other two are configured as a discharge route 15. As the needle tube and the hoop material, stainless steel was used in this embodiment, but when used under MRI or the like, gold-plated brass to prevent artifacts due to instruments,
High nickel alloys (low iron), titanium and titanium alloys are selected.

A description will be given of the means for attaching the hoop material 13a. Before combining the inner tube 12 and the outer tube 11, appropriate non-attached portions are left at both ends of the inner tube 12 at the aforementioned symmetric positions of the inner tube 12, respectively. Two hoops 13a
Are attached to the inner tube 12 at appropriate intervals by spot welding, and inserted into the outer tube 11 for setting. At this time, the length in the width direction of the hoop material 13a is
If both ends in the width direction of the hoop material 13a are set slightly longer than the length of the position in contact with the inner surface of the outer tube 11, both ends in the width direction of the hoop material 13a are curved and come into surface contact with the inner surface of the outer tube 11,
More reliable isolation.

FIG. 3 is an AA cross-sectional view of a needle tube when a metal wire is used as a separating means, which is a guide needle outer needle used for PMCT in the same manner as described above, and an external view for explaining means for attaching the separating means. FIG. 4 is a cross-sectional view taken along the line A-A of a state where a metal wire is attached to the inner tube before setting the tube and the inner tube. In the gap between the hollow inner pipe 12 and the outer pipe 11 arranged on the concentric circle, two metal wires 13 b dividing the gap in the axial direction of the needle tube 1 are inserted into the inner pipe 1.
2 are provided in parallel at symmetrical positions facing each other, and one side of a gap divided into two by the metal wire 13b is configured as a cooling water supply line 14 and the other side is configured as a discharge line 15. In the case of this means, the inner diameter of the outer tube 11 is required to be the same as the sum of the outer diameter of the two metal wires 13b and the outer diameter of the inner tube 12 for reliable isolation. It is necessary that the inner diameter of the outer tube 11 be slightly larger, and the mixing of the cooling water on the supply side and the discharge side is practically inevitable. Therefore, this is not applicable when truly reliable isolation is required. Since the mixing is only slightly stopped, the PMCT guide needle of the present embodiment does not hinder the cooling effect or the like in actual use. Further, in this embodiment, stainless steel wire is used for the material, but for the purpose of MRI or the like, the above-mentioned metal may be used.

A description will be given of the means for attaching the metal wire 13b. Before assembling the inner tube 12 and the outer tube 11, non-attached portions which are respectively appropriate at both ends of the inner tube 12 are left at the above-mentioned symmetric positions of the inner tube 12, Two metal wires 13b are attached to the inner tube 12 by spot welding at appropriate intervals at several places, and these are inserted into the outer tube 11 and set. that time,
As described above, the inner diameter of the outer tube 11 is set slightly larger than the sum of the outer diameter of the inner tube 12 and the outer diameters of the two metal wires 13b to facilitate insertion.

FIG. 4 is a sectional view taken along the line BB of a portion near the distal end of the needle tube, which is a guide needle outer needle used for the PMCT of the present invention and uses a metal wire as a separating means. Note that the same applies to the case where the hoop material 13a is used as the separating means, and the drawings and description are omitted. Explaining the vicinity of the distal end of the guide needle outer needle 10 of the present embodiment, the outer tube 1 arranged concentrically
The inner tube 1 and the inner tube 12 are formed such that the inner tube 12 slightly projects from the outer tube 11, and the distal end of the outer tube 12 is formed into a tapered shape 16 by laser welding so that the needle tube 1 has a shape capable of puncturing a human body. It is welded to the protruding inner tube 12 and closes the gap between the inner tube 12 and the outer tube 11. The metal wire 13b serving as a separating means is provided with an end shorter than the end of the outer tube 11 so that the cooling water supply route 14 and the discharge route 15 communicate with each other at the end, and the end is used as a passage as shown by an arrow in the drawing. A simple reflux path is formed.

FIG. 5 is a vertical cross-sectional view of a part of a base portion B-B of a needle tube when a metal wire is used as a separating means, which is a guide needle outer needle used for the PMCT of the present invention. Note that the same applies to the case where the hoop material 13a is used as the separating means, and the drawings and description are omitted. The base portion of the outer needle 10 of the guide needle according to the present embodiment will be described. The outer tube 11 and the inner tube 1 are arranged concentrically.
Numerals 2 are bonded and fixed to the needle base 2 of the resin molded product. At this time, the needle base 2 has a structure that reliably closes the gap between the outer pipe 11 and the inner pipe 12 to prevent leakage of the cooling water from the base.
Metal wire 13b of separation means to prevent mixing of cooling water
Is provided at the same position as the end of the outer tube 11 or at a longer position, so that the routes 14 and 15 can be reliably isolated.

Further, holes 18 serving as cooling water passages are provided in the side surfaces of the outer pipe 11 at positions corresponding to the cooling water supply route 14 and the discharge route 15, respectively. A tube 3 and a discharge tube 4 for discharging cooling water to the outside are provided by bonding to a tube connecting portion 19 provided on the needle base 2, and the hole 18 communicates with each tube end inside the needle base 2. , A cooling water return route is formed as shown by the arrows in the figure. Thus, the cooling water supplied to the supply tube 3 of the needle base 2 from the cooling water supply device (not shown) passes through the gap on one side of the inner tube 12 and the outer tube 11 of the needle tube 1 and is inverted near the distal end of the needle tube. Then, a recirculation route for discharging from the discharge tube 4 through the gap between the needle tubes on the other side is formed.

FIG. 6 is a vertical cross-sectional view taken along the line C-C of the needle tube for explaining the guide needle outer needle used in the PMCT according to the present invention and illustrating the opening position of the hole in the needle tube outer tube when the hoop material is used as the separating means. The figure is shown. (A) is divided into two large and small cross-sectional areas by two hoops 13a in the manner described above in the gap between the hollow inner pipe 12 and the outer pipe 11 arranged concentrically.
Among the divided gaps, one side having a large cross-sectional area is configured as a cooling water supply route 14 and the other side is configured as a discharge route 15, and a hole 18 opened in the outer pipe 11 is formed of two hoop materials. Water supply and drainage openings are provided facing each other at positions communicating with gaps having a large cross-sectional area between them.
In this case, although a small amount of cooling water infiltrates into the gap 16 having a small cross-sectional area, the base end is closed by the needle base 2 as described above, so that there is no escape route for air, and there is practically only a slight escape. Since there is only a small gap, there is little hindrance in actual use such as a cooling effect.

(B) shows the four divided gaps.
The two adjacent large and small gaps are configured as a supply route 14 and the other two are configured as a discharge route 15.
The hole 18 is provided with a water-absorbing and drain-water opening facing each other at a position in contact with and communicating with both a gap having a large cross-sectional area and a gap having a small cross-sectional area with one end of the hoop material interposed therebetween. In this case, the above-described problem is also eliminated because the gap having a small cross-sectional area also serves as a passage, and a large amount of the cooling medium recirculates over a larger area, so that a higher cooling effect can be obtained.

[0021]

According to the present invention, according to the above-described operation, for example, in the case of PMCT, damage to healthy tissue due to excessive heating due to the cooling effect of the puncture route is prevented, and the use of a drug that requires heating can be prevented. In the case of injection or the like, it is possible to effectively treat a target site by preventing the temperature of the medicine from decreasing due to the heat retention effect. In addition, since the outer diameter of the needle tube to be punctured is minimized, a device that is less invasive and less burdensome on the human body can be provided.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a puncture needle used for PMCT according to an embodiment of the present invention.

FIG. 2 is an AA cross-sectional view of a PMCT guide needle according to an embodiment of the present invention using a hoop material as a separating means and an AA cross-sectional view for explaining a hoop material attaching means.

FIG. 3 is an AA cross-sectional view of a PMCT guide needle according to an embodiment of the present invention using a metal wire as a separating means and an AA cross-sectional view for explaining a metal wire attaching means.

FIG. 4 is a view showing a part of the outer periphery of a needle tube near the tip of a needle tube using a metal wire as a separating means in the outer needle of the PMCT guide needle according to the embodiment of the present invention.
B vertical section

FIG. 5 is a vertical cross-sectional view of a part of a needle tube using a metal wire as a separating means in a PMCT guide needle according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view taken along the line CC of the needle tube for explaining the opening position of the hole using the hoop material as the separating means in the outer needle of the PMCT guide needle according to the embodiment of the present invention.

[Explanation of reference numerals] Guide needle outside needle 1. Needle tube 11. Outer tube 12. Inner tube 13a. Separation means (hoop material) 13b. Separation means (metal wire) Supply route 15. Discharge route 16. 17. Small cross-sectional area gap Tapered section 18. Hole 19. Tube connection part 2. Needle base 3. Supply tube 4. Discharge tube 20. Needle in guide needle 30. electrode

Claims (3)

[Claims] 1. A separation means for separating a gap between an inner pipe and an outer pipe made of a hollow metal pipe arranged on a concentric circle into at least two in an axial direction, wherein the separated gap forms a return pipe and a needle tube. A needle base provided at the base end of the needle tube for fixing the needle tube, and a supply tube provided to be connected to the needle base and serving as a passage for supplying fluid from outside to the needle tube return path and discharging fluid from the needle pipe return path to the outside And a fluid return needle comprising a discharge tube. 2. The fluid recirculation needle according to claim 1, wherein said separating means is provided with a hoop material (a thin metal plate) in a gap between said inner tube and said outer tube. 3. The liquid recirculation needle according to claim 1, wherein said separating means provides a metal wire in a gap between said inner tube and said outer tube.