JP2005323898A - Injection needle and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily thrust an injection needle into biological tissue and to reduce a cut width for cutting the tissue open. <P>SOLUTION: In this injection needle formed with a cutting edge part by grinding the tip part of a needle tube obliquely, both sides of the needle tip of the needle tube 11 are provided with first cutting edge parts 131, 141 formed with sharp edges 131, 141 at the outer peripheral edges of cutting edge faces extending in an outer peripheral direction, and second cutting edge parts 132, 142 formed with edges with the rounded outer peripheral edges of the cutting edge faces continuous with the first cutting edge parts 131, 141. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a medical injection needle, in particular, an injection needle with a blade at the tip and a method of manufacturing the same.

Injection needles have long been used for medical purposes, and there are cutting needles with blades at the tips and non-cutting needles.
A typical cutting needle is a quinque needle, which has two blade surfaces ground in a mountain shape and is widely used. There is also a green needle with one blade surface (see Non-Patent Document 1).
On the other hand, the non-cutting needle is also referred to as a pencil point needle and has a conical tip, which is mainly used for anesthesia.

FIG. 7 is a plan view showing a quinke needle described in the conventional non-patent document 1, and FIG. 8 is a cross-sectional view taken along the line CC.
A first blade surface 2 that is obliquely ground in the axial direction of the needle tube 1 and a second blade surface 3 and a third blade that are connected to both ends of the first blade surface 2 and ground in a mountain shape. Surface 4.
As shown in FIG. 8, the outer peripheral edges 3a and 4a of the second blade surface 3 and the third blade surface 4 form a sharp blade tip as a whole and are easy to puncture.

However, when the cutting edge is pierced into the human tissue, the sharp cutting edge is large, so there is a problem that not only is there stinging, but also the cutting width for cutting the tissue becomes large, and it takes time to repair it.
Therefore, various improvements have been proposed.

For example, the needle tip side is curved so as to be thin to reduce stinging and to quickly recover the piercing trace (see Patent Document 1).
Also, the tip of the needle tip has a sharp conical shape, and the outer peripheral wall surface of the hem is formed in a round shape so that no sharp blade can be formed. (See Patent Document 2).

Takayasu Yasumi, “Sticking” Local Anesthesia, Medical Science International Co., Ltd., issued July 15, 2002 109-112 Japanese Patent No. 3310270 JP-A-11-276586

However, since the tip described in Patent Document 1 is curved, the insertion length of the needle is slightly shortened, but the blade portion in the insertion width direction does not change. It will open up the human body by the size of.
The one described in Patent Document 2 has no blade oriented in the direction of entry of the injection needle and does not cut biological tissue. Therefore, it cannot be called a cutting needle with a blade, and the blade is not at all. Since there is no needle, there is a problem that it is difficult to puncture when using an injection needle.

  An object of the present invention is to make it easier to pierce a living tissue with an injection needle and to reduce a cutting width for opening the tissue.

  In order to solve the above-described problems, the present invention provides an injection needle in which a tip portion of a needle tube is obliquely ground to form a blade portion, and is sharp on the outer peripheral edge of the blade surface extending in the outer peripheral direction on both sides of the needle tip of the needle tube. A first blade portion having a blade edge and a second blade portion continuous with the first blade portion and formed with a blade edge with a rounded outer peripheral edge of the blade surface are provided.

The present invention comprises, on both sides of the needle tip, a first blade portion that forms a sharp blade edge, and a second blade portion that forms a round outer peripheral edge of the blade surface continuous to the first blade portion, It is easy to pierce the injection needle, and the cut width for cutting the living tissue can be made small, and there is an effect that it takes less time to repair the cut.
Moreover, since the structure as an injection needle is simple, there exists an advantage that manufacturing cost is low.

In particular, when the injection needle of the present invention is used as a spinal anesthesia needle (a spinal cord subarachnoid anesthesia needle), there is no leakage of cerebrospinal fluid or anesthetic solution because the dural cut is small, and nerves in the subarachnoid space are also present. This has the effect of reducing the risk of damage.
Furthermore, there is an advantage that resistance is large when puncturing the dura mater, and the click feeling of the needle tip entering the subarachnoid space is large and easy to detect.

  The present invention includes a first blade surface that is obliquely ground in the axial direction of the needle tube at a tip portion of the needle tube, and a second blade surface and a third blade surface that are connected to both sides of the first blade surface and ground in a mountain shape. A first blade part having a sharp blade edge formed on the outer peripheral edge of the blade surface extending in the outer circumferential direction from the needle tip on each of the second blade surface and the third blade surface; and a blade surface continuous with the first blade portion This was realized by including a second blade portion having a blade edge with a rounded outer peripheral edge.

1A and 1B are diagrams showing Embodiment 1 of the present invention, in which FIG. 1A is a plan view showing a tip portion of an injection needle and other portions are omitted, and FIG. 1B is a side view of the same.
The injection needle of Example 1 shows an example of a quinke needle that is a representative of a cutting needle, and a first blade surface 12 that is obliquely ground in the axial direction of the needle tube 11 at the tip of a hollow pipe-shaped needle tube 11; A second blade surface 13 and a third blade surface 14 that are connected to both ends of the first blade surface 12 and ground in a mountain shape are provided. The configuration so far is the same as the conventional one.

On the needle tip side of the second blade surface 13, a first blade portion 131 is formed in which a sharp blade tip is formed on the outer peripheral edge of the blade surface extending in the outer circumferential direction of the needle tube 11. Furthermore, the 2nd blade part 132 which formed continuously from the 1st blade part 131 and formed the blade edge | round | yen which rounded the outer periphery of the blade surface is provided.
Although the direction of the third blade surface 14 is different from that of the second blade surface 13, a first blade portion 141 and a second blade portion 142 that are symmetrically formed in the same manner are formed.

2A and 2B are cross-sectional views of the first embodiment. FIG. 2A is a cross-sectional view taken along the line AA in FIG. 1, and FIG.
The 1st blade part 131 formed in the 2nd blade surface 13 and the 1st blade part 141 formed in the 3rd blade surface 14 form a sharp blade edge, as shown to (a).
On the other hand, the 2nd blade part 132 of the 2nd blade surface 13 and the 2nd blade part 142 of the 3rd blade surface 14 form the blade edge which rounded the outer periphery, as shown in (b).

The first blade portions 131 and 141 are well cut because the blade edges are sharply formed, but as can be seen from FIG. 1, the first blade portions 131 and 141 are much smaller than the second blade portions 132 and 142. When puncturing a living tissue, it is easy to puncture and the width of cutting the tissue can be reduced.
In addition, since the second blade portions 132 and 142 larger than the first blade portions 131 and 141 have a rounded blade tip and are made like an uncut knife, the tissues are pushed apart without cutting the living tissue. To enter. For this reason, it is said that after the needle is pulled out, the tissue immediately closes the hole where the needle has been inserted, so that the wound is repaired quickly.

Generally, a needle tube is formed of a hollow cylindrical pipe made of a metal, for example, a cold rolled stainless steel plate. For medical use, a needle tube having an outer diameter of about 0.3 to 3 mm is used.
The length of the first blade portions 131 and 141 in the axial direction is suitably 0.05 to 0.5 mm in consideration of the outer diameter of the needle tube described above.
Although the length is 0.05 mm when the outer diameter is 0.3 mm and 0.5 mm when the outer diameter is 3 mm, it does not correspond strictly, but the outer diameter and the axial direction of the first blade portions 131 and 141 The length of is very relevant.

Although it differs depending on the opening angle of the first blade portions 131 and 141 with respect to the axial direction, in the case of FIG. 1, it is about 45 °, and the length of the first blade portions 131 and 141 in the axial direction is about the cut width. Doubled.
Therefore, if the length in the axial direction is large, the cutting width will be further increased.
On the other hand, if the injection needle is too small, so-called cutting becomes worse when the injection needle is inserted into the living tissue, and it becomes difficult to insert the needle.

For example, in the case of a needle having an outer diameter of 0.7 mm used as an anesthetic injection needle, by setting the first blade portions 131 and 141 to 0.08 mm, the cutting width becomes 0.16 mm, which is easy to puncture, which is compared with the conventional case. Thus, the cut end can be greatly reduced. Incidentally, in the conventional case, the cut edge is equivalent to the second blade portions 132 and 142, so the cut width is about 0.6 mm, which is slightly smaller than the outer diameter.
Moreover, since the length of the 2nd blade parts 132 and 142 will be 0.42 mm, and an outer diameter is 0.7 mm, resistance is large and the click feeling at the time of penetrating a dura can fully be acquired.

As described above, according to the first embodiment, the first blade part having the sharp edge formed on the outer peripheral edge of the blade surface extending in the outer circumferential direction on both sides of the needle tip, and the blade surface continuous with the first blade part. By providing a second blade part with a rounded outer peripheral edge, it is possible to make the injection needle easy to puncture and to reduce the cutting width for opening the living tissue at the time of puncturing, and to repair the cut. There is an effect that does not take.
In addition, since the structure as an injection needle is simple, it is possible to process a large number of needles at a time, and there is an advantage that the manufacturing cost is low.

In particular, when the injection needle of the present invention is used as a spinal anesthesia needle (spinal spinal anesthesia needle), since the first blade portion of the sharp blade tip is small, the cut edge when cutting the dura mater is small, so There is no leakage of cerebrospinal fluid or anesthetic fluid in the extramembrane space, and there is an effect that there is less fear of damaging nerves in the subarachnoid space.
Leakage of cerebrospinal fluid in the subarachnoid space or injected anesthetic fluid into the epidural space is thought to cause postoperative headaches.
Furthermore, since the first blade portion of the needle tip is small and the second blade portion of the round blade tip is large, there is a large resistance when puncturing the dura mater, and the click feeling of the needle tip entering the subarachnoid space is large and sensed. There is also an advantage that it is easy to understand, that is, the perforation of the dura is easy to understand.
The fact that the penetration of the dura is easy to understand means that it is possible to confirm whether the injection needle has penetrated the dura mater and entered the subarachnoid space, and can accurately inject an anesthetic solution into the subarachnoid space. It means that.

FIG. 3 is a plan view showing Embodiment 2 of the present invention, showing the distal end portion of the injection needle, and omitting other portions.
In the first embodiment, the second blade surface and the third blade surface are formed small, and the ridgeline formed by the second blade surface and the third blade surface is configured to be short. The third blade surface 24 is enlarged, and the ridgeline formed by the second blade surface 23 and the third blade surface is configured to be as long as the needle tube 21 is full. Other components are the same as those in the first embodiment.

That is, the first blade surface 22 is formed by obliquely grinding the tip of the needle tube 21, the second blade surface 23 and the third blade surface 24 are formed on both sides of the first blade surface 22, and the second blade surface 23 is formed. The third blade surface 24 is connected in a mountain shape at the needle tip, and a long ridge line is formed.
A first blade portion 231 having a sharp blade edge and a second blade portion 232 having a round blade edge are formed on the second blade surface 23, and a first blade having a sharp blade edge is formed on the third blade surface 24. A portion 241 and a second blade portion 242 having a round blade edge are formed.
Therefore, according to the second embodiment, the same effect as the first embodiment can be obtained.

FIG. 4 is a plan view showing Embodiment 3 of the present invention, showing the distal end portion of the injection needle, and omitting other portions.
Example 3 shows an example of a green needle, and a first blade surface 32 that is ground obliquely in the axial direction of the needle tube 31 is formed at the tip of the needle tube 31. A first blade part 321 having a sharp edge at the outer peripheral edge of the blade surface extending in the outer peripheral direction of the needle tube 31 is formed on both sides of the tip of the first blade surface 32, and the blade surface is continuous with the first blade part 321. The 2nd blade part 322 which has the blade edge | round | yen which rounded the outer peripheral part of is formed.

  In the case of Example 3, since the second blade surface and the third blade surface such as a quinke needle are not formed, there are problems in insertion pain and insertion pressure, but the same effect as in Example 1 Can expect.

FIGS. 5A and 5B are views showing a method of manufacturing the injection needle of the present invention, where FIG. 5A is a plan view and FIG. 5B is a side view. The needle of Example 1 will be described as an example. As shown in (a), the tip is first ground obliquely and sharp on the outer peripheral edges of the blade surfaces 13, 14 extending in the outer peripheral direction on both sides of the needle tip, respectively. A needle tube 11 having a cutting edge is prepared.
In this case, the needle tube 11 is formed with a first blade surface 12, a second blade surface 13 with a sharp blade, and a third blade surface 14.
A plurality of needle tubes 11 are arranged on the jig plate 16 and are fixed in position by means such as taping.

Next, a mask 15 having a width w is formed in a region where the first blade portions 131 and 141 on the needle tip side of the second blade surface 13 and the third blade surface 14 are formed. The mask 15 covers the region with a width w of 0.05 to 0.5 mm in order to set the axial length of the first blade portions 131 and 141 to 0.05 to 0.5 mm. It is composed of a synthetic resin plate, rubber plate, metal plate, adhesive tape, and the like.
If the mask 15 such as a synthetic resin plate can be precisely moved by using a tool (not shown) in order to accurately cover a minute length region so that a large number of needle tubes 11 can be processed collectively. good.

Next, as shown in (b), small particles of the abrasive 17 are sprayed from the upper side to the tip of the needle tube 11, that is, the second blade surface 13 and the third blade surface 14, as shown by the arrow, and the first mask is not masked. The sharp edge of the outer peripheral edge of the region forming the second blade portion 132 of the second blade surface 13 and the second blade portion 142 of the third blade surface is crushed and rounded, the blade is eliminated, and the second blade portion 132, 142 is formed.
The abrasive 17 is commercially available for blasting, and glass-based, ceramic-based, or metal-based glass beads, sandblasting sand, or the like is used.
The processing method for spraying the abrasive 17 is well known, and rounding the blade edge can be easily performed.

Next, when the mask 15 covering the area where the first blade portions 131 and 141 are formed is removed, the first blade portions 131 and 141 with sharp blade edges remaining because they are protected by the mask 15 are formed.
In this way, the first blade portions 131 and 141 having sharp blade edges and the second blade portions 132 and 142 having round blade edges continuous with the first blade portions 131 and 141 are formed, and the injection needle is formed. Complete.
In addition, although description was abbreviate | omitted, in order to remove the burr | flash which can be made in the jaw part 18 of the needle tube 11, the abrasives are sprayed toward the jaw part 18 from the direction of the needle tip. By changing the blowing direction so as to blow from above or obliquely above the region where the second blade portions 132 and 142 are formed, the above-described step of rounding the blade edge can be easily performed.

  Therefore, according to the manufacturing method of the present invention, it is possible to process a large number of needle tubes at once, and there is an advantage that the manufacturing cost is low.

FIG. 6 is a view showing a use state as a spinal anesthesia needle.
The state where the injection needle of the present invention is used as the spinal anesthesia needle 41 and the anesthetic liquid 43 in the syringe barrel 42 of the syringe is injected into the spine of the human body is shown.
The human body is shown in a sectional view. The outermost side is skin 51, the next layer is ligament 52, the next is epidural space 53, and the inner side of the outer space is dura 54. The arachnoid membrane 55 is formed in a bag shape inside the dura mater 54, in which the cerebrospinal fluid circulates in the subarachnoid space 56 between the two layers of the arachnoid membrane 55, and the cauda equina 57 runs.

The spinal anesthesia needle 41 is omitted on the way and the human body side is enlarged, but the anesthetic liquid 43 is injected through the anesthetic needle 41 into the subarachnoid space 56 as indicated by an arrow and acts on the caudadial nerve 57 to apply anesthesia. .
At the time of injection, the anesthesia needle 41 is punctured and reaches the dura 54 through the skin 51, the ligament 52, and the epidural space 53. The anesthesia needle 41 has a first blade portion with a small sharp edge. Therefore, the first blade portion cuts through the fibers of the dura mater 54 slightly and penetrates easily.
However, the dura 54 is hard, and the second blade following the first blade has a rounded cutting edge. Therefore, there is a great resistance to push the fibers of the dura 54 separately, and the penetrating membrane The penetration feeling when reaching the lower cavity 56, that is, the clicking feeling is large and can be easily detected.
Therefore, the anesthetic solution 43 can be accurately injected into the subarachnoid space 56.
The cut width by the first blade portion is small, there is no leakage of cerebrospinal fluid or anesthetic fluid 43 to the epidural space 53, there is little possibility of damaging the cauda equina 57 in the subarachnoid space 56, and the cut is repaired. Of course, it is fast.

It is a figure which shows Example 1 of this invention. 1 is a cross-sectional view of Example 1. FIG. It is a figure which shows Example 2 of this invention. It is a figure which shows Example 3 of this invention. It is a figure which shows the manufacturing method of this invention. It is a figure which shows the use condition as a spinal anesthesia needle. It is a top view which shows the conventional injection needle. It is sectional drawing of the conventional injection needle.

Explanation of symbols

11, 21, 31 Needle tube 12, 22, 32 First blade surface 13, 23 Second blade surface 14, 24 Third blade surface 131, 141, 231, 241, 321 First blade portion 132, 142, 232, 242 , 322 Second blade portion 15 Mask 16 Jig plate 17 Abrasive material 18 Chin portion

Claims (6)

In the injection needle in which the tip of the needle tube is ground obliquely to form the blade part,
A first blade part having a sharp edge formed on the outer peripheral edge of the blade surface extending in the outer peripheral direction on both sides of the needle point of the needle tube;
An injection needle comprising: a second blade portion that is continuous with the first blade portion and has a blade edge with a rounded outer peripheral edge of the blade surface.   A first blade surface that is obliquely ground in the axial direction of the needle tube, and a second blade surface and a third blade surface that are connected to both sides of the first blade surface and are ground in a mountain shape. 2. The injection needle according to claim 1, wherein the first blade portion and the second blade portion are formed on each of the second blade surface and the third blade surface.   The injection needle according to claim 1 or 2, wherein an axial length of the first blade portion is 0.05 to 0.5 mm. Preparing a needle tube having a sharp cutting edge formed on the outer peripheral edge of the blade surface extending in the outer circumferential direction on both sides of the needle tip by obliquely grinding the tip portion; and
Masking the region forming the first blade portion on the needle tip side of the blade surface;
Spraying abrasive on the tip of the needle tube, rounding the outer periphery of the region forming the second blade continuous with the region of the first blade,
And a step of removing the mask.   5. The method of manufacturing an injection needle according to claim 4, wherein a mask having a width of 0.05 to 0.5 mm is formed in a direction perpendicular to the axial direction of the needle tube.   6. The method for manufacturing an injection needle according to claim 4, wherein the mask is made of any one of a synthetic resin plate, a rubber plate, a metal plate, and an adhesive tape.

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