JPH07143992A - Puncture needle assembly - Google Patents

Abstract

PURPOSE:To prevent reliably unintentional injury of an internal organ, etc., caused by a puncture needle. CONSTITUTION:A puncture needle assembly 1 has a puncture needle 2 consisting of a hollow pipe, a holding member 3 constituting a holding part of the puncture needle 2, a protective member 4 inserted movably in the axial direction into the inner cavity of the puncture needle 2 and a spring (an energizing means) 5 for biasing the protective member 4 in the apex direction. A sharp needle end part 21 is formed on the end of the puncture needle 2. A covering part 42 is formed on the end of the protective member 4 and when the covering part 42 is projected from the end opening 23 of the needle end part 21 by moving the protective member 4 toward the end, the tip 24 of the needle end part 21 is covered by the curve of the end part 44 of the covering part to protect an internal organ, etc. In addition, in the holding part 3, a locking mechanism 6 for controlling the movement of the protective member 4 and a retreat preventing mechanism 8 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a puncture needle assembly for use in, for example, a body cavity surgery.

[0002]

2. Description of the Related Art Recently, in excision of the appendix or gallbladder,
Laparoscopic surgery, which is performed without laparotomy, is attracting attention in place of conventional open surgery. In this laparoscopic surgery, as shown in FIG. 8, for example, four trocar tubes 10 are inserted into the abdominal cavity 101 penetrating the abdominal wall 100, and a small trocar tube 10 is inserted into the small abdominal cavity. The inside of the abdominal cavity 101 is displayed on the monitor image 103 by the camera 102, and the forceps 104, the scissors 105, and the electric scalpel 106 respectively inserted through the other trocar tubes 10 are appropriately operated while observing the monitor image 103, and the abdominal cavity 101 The operation is performed inside.

By the way, in such laparoscopic surgery, in order to penetrate the trocar tube 10 into the abdominal wall 100,
First, a puncture needle is punctured at a target site on the abdominal wall 100, and then the trocar tube 10 is inserted along the outer circumference of the puncture needle. When the puncture needle is punctured on the abdominal wall, an organ or other tissue in the abdominal cavity is inserted. A puncture needle (trocar) equipped with a safety mechanism has been proposed in order to protect it from a sharp needle tip (Japanese Patent Laid-Open No. Hei 5).
No. 168644).

This trocar has a hollow puncture needle (obturator) having a sharp blade tip, a shield inserted axially movably into the inner cavity of the puncture needle, and a puncture of the shield. The needle has a coil spring that is biased toward the tip side of the needle, and the tip of the shield has a hemispherical shape. Then, when the puncture needle penetrates the biological tissue, the shield body projects to a position beyond the tip of the puncture needle beyond the cutting edge by the action of the coil spring, and protects an organ or the like in the abdominal cavity.

However, in such a conventional trocar, the puncture needle makes a hole corresponding to the outer diameter of the living tissue (abdominal wall), and the tip of the shield receives resistance from the living tissue. Until that time, that is, until the entire tip opening of the puncture needle is punctured to a depth such that it is exposed inside the abdominal cavity, the shield does not protrude from the tip opening of the puncture needle, and the function of protecting the organs and the like is obtained. Therefore, for example, when the speed of puncturing the puncture needle is high, or when the punctured living tissue (abdominal cavity) is close to or in close contact with the internal organs or the like, the protrusion of the shield does not catch up with the needle. There is a risk of damaging the organ depending on the destination.

As described above, in the conventional puncture needle with a safety mechanism, the function of protecting living tissue is incomplete, and sufficient safety to endure actual use is not ensured.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly safe puncture needle assembly capable of reliably preventing undesired damage to an organ or the like by a puncture needle.

[0008]

The above object is achieved by the present invention described in (1) below. Also, the following (2)-
(9) is preferable.

(1) A puncture needle assembly used for guiding a tubular body penetrating a living tissue, which is a hollow puncture needle having a needle tip at its tip and is movable in the puncture needle in the axial direction thereof. Inserted into the elastic member, the protective member having an elastically deformable covering portion, and a biasing means for biasing the protective member toward the needle tip portion side, when puncturing the biological tissue with the puncture needle, the The coating portion is configured to project from the tip opening of the puncture needle and deform to cover at least the vicinity of the tip of the needle tip portion as the reaction force received from the living tissue decreases. Assembly.

(2) The puncture according to (1) above, wherein the needle tip portion has a blade surface that is inclined with respect to its axis, and the covering portion has an inclination that is more acute than the inclination angle of the blade surface. Needle assembly.

(3) The puncture needle assembly according to (1) or (2), wherein the covering portion has a step portion whose thickness changes stepwise.

(4) When the covering portion is located inside the tip opening of the puncture needle, it is restricted by the inner surface of the puncture needle, and when it protrudes from the tip opening of the puncture needle, the restriction is released. The puncture needle assembly according to any one of (1) to (3), wherein the puncture needle assembly returns to a state of being curved toward the tip of the needle tip.

(5) The puncture needle assembly according to any one of the above (1) to (4), which has a lock mechanism for limiting the movement of the protective member toward the needle tip side.

(6) The lock mechanism is provided in a grip portion formed on the proximal end side of the puncture needle, and when the puncture needle is inserted into the tubular body to a predetermined depth, the protection member by the lock mechanism is provided. The puncture needle assembly according to the above (5), which is configured to release the restriction of movement of the puncture needle.

(7) The puncture needle assembly according to any one of the above (1) to (6), which has a retracting prevention mechanism for preventing the protective member from retracting.

(8) The puncture needle assembly according to the above (7), wherein the receding prevention mechanism is provided in a grip portion formed on the proximal end side of the puncture needle.

(9) The puncture needle assembly according to any one of the above (1) to (8), which has a display means for knowing a protruding length of the covering portion from the tip opening.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The puncture needle assembly of the present invention will be described in detail below with reference to the preferred embodiments shown in the accompanying drawings.

FIGS. 1 and 2 are a longitudinal sectional view and a partial longitudinal sectional view, respectively, showing a structural example of the puncture needle assembly of the present invention, and FIG. 3 is a structural example of the tip portion of the puncture needle assembly of the present invention. FIG. The right side in FIGS. 1 and 2 is called the base end, and the left side is called the tip.

As shown in these figures, the puncture needle assembly 1
Is a puncture needle 2 formed of a hollow tube, a gripping member 3 that constitutes a gripping portion of the puncture needle 2, a protection member 4 that is inserted into the inner cavity of the puncture needle 2 so as to be movable in the axial direction, and is protected. It has a spring (biasing means) 5 for urging the member 4 in the distal direction.

A sharp needle tip portion 21 is formed at the tip of the puncture needle 2. The needle tip portion 21 has a blade surface 22 that is inclined at a predetermined angle with respect to the axis of the puncture needle 2. Further, as shown in FIG. 3, the tip end opening 23 of the needle tip portion 21 has an elliptical shape.

The inclination angle α of the blade surface 22 is not particularly limited, but is preferably about 10 to 30 °, particularly about 20 to 28 °. Further, the formation area of the blade surface 22 (polished portion) is not particularly limited. For example, even if the blade surface 22 is formed over the entire circumference around the tip opening 23, as shown in FIG. It may be formed up to about half the position.

Such a puncture needle 2 is made of, for example, a metal material such as stainless steel or aluminum or a hard plastic, and its outer diameter is preferably 1 to 15.
The inner diameter is preferably about 80 mm and the inner diameter is preferably about 80 to 95% of the outer diameter.

The suitable length of the puncture needle 2 varies depending on the purpose of use and the case, but when it is used for laparoscopic surgery, the length of the body insertion part is 50 to 50 when puncturing a living tissue.
The length is preferably 200 mm. Also,
A hollow grasping member 3 is fixedly connected to the proximal end of the puncture needle 2.

The protective member 4 has a rod-shaped protective member main body 41, and an elastically deformable covering portion 42 is formed at the tip thereof. It is preferable that the covering portion 42 has a step portion 43 that is formed thinner than the protective member main body 41 and that the thickness thereof gradually decreases toward the tip. By forming the step portion 43 as described above, the tip portion 24 of the needle tip portion 21 is covered with the covering portion 42 in a stepwise manner, and it is possible to prevent the area covering the blade surface 22 from increasing more than necessary, and to improve the puncture resistance. Can be as small as possible.

As shown in FIG. 4, the inclination angle β of the line segment connecting the tip and the base end of the covering portion 42 on the step side (hereinafter referred to as the inclination angle of the covering portion 42) is greater than the inclination angle α. It is preferably small, and specifically, it is preferably about α-5 to α-15 °. Further, the tip of the covering portion 42 preferably has a rounded shape in order to protect living tissue.

The tip portion of the covering portion 42, that is, the portion (tip portion 44 of the covering portion) closer to the tip end than the first step portion 43 from the tip end has a tongue shape in the illustrated configuration. In a natural state (state in which no external stress is applied), as shown in FIG. 7, the needle tip portion 21 is curved (or bent) toward the tip 24 side, but as shown in FIG.
When the entire covering portion 42 is located inside the distal end opening 23 (inside the lumen of the puncture needle 2), it is regulated by the inner surface of the puncture needle 2 so as to extend the curvature, that is, to reduce the curvature of the curvature. Is elastically deformed. Therefore, when the tip end portion 44 of the covering portion is projected from the tip end opening 23 of the puncture needle 2, the regulation is released and the tip 24 is returned to the curved state to cover the tip 24.

As the constituent material of the covering portion 42, for example,
Polyethylene, polypropylene, rigid polyvinyl chloride,
Polymeric materials with elasticity such as acrylic resin, polyester, polyamide, ABS resin, polyurethane, polycarbonate, various synthetic rubbers, metal materials such as various steel materials, spring materials, shape memory alloys, superelastic alloys, or a combination thereof as appropriate. There are some. Further, a core member made of such a material (particularly, a metal material) may be embedded in the covering portion 42 or bonded to the surface thereof to give elasticity to the covering portion 42.

The protection member body 41 preferably has a circular cross section, and its outer diameter is preferably set to a value equal to or slightly smaller than the inner diameter of the puncture needle 2. In this case, the protective member main body 41 may be a hollow rod-shaped body with a closed tip.

The length of the protective member 4 is the same as that of the puncture needle 2
It is preferably about 2 to 20 mm, more preferably about 5 to 10 mm longer than the length of the body insertion part.

In the present invention, in order to improve the slidability of the protective member 4, the outer surface of the protective member 4 and / or the inner surface of the puncture needle 2 are treated to reduce the coefficient of friction. You can also Examples of such treatment include surface smoothing, application of various lubricants and surfactants, or, for example, polytetrafluoroethylene (Teflon), carbon powder blended resin, fluoride, polyethylene, Teflon powder blended resin, The formation of a coating layer of a low friction material such as an oil-impregnated polymer may be mentioned.

By carrying out such a treatment for reducing the coefficient of friction, the sliding resistance of the protective member 4 is reduced,
Responsiveness of the operation in which the covering portion 42 projects from the tip opening 23,
Trackability is improved. In addition, such a process is performed by the puncture needle 2
May be provided on the outer surface and / or on the inner surface of the trocar tube 10.

The puncture needle 2 is used, for example, by inserting it into a trocar tube 10 which penetrates the abdominal wall and communicates with the abdominal cavity and the outside of the body. A taper 11 is formed at the tip of the trocar tube 10 so that its outer diameter gradually decreases toward the tip, and a hub 12 is fixedly connected to the base end of the trocar tube 10.

Such a trocar tube 10 is, for example,
It is made of a hard resin such as polyethylene, polypropylene or acrylic resin, a metal material such as stainless steel or aluminum, or various ceramics, and its inner diameter is equal to or slightly larger than the outer diameter of the puncture needle 2. The outer diameter is preferably within the inner diameter + 3 mm.

Further, as shown in FIG. 1, the length of the trocar tube 10 is such that when the puncture needle 2 is inserted into the trocar tube 10 to puncture living tissue, the puncture needle 2 is inserted from the tip opening of the trocar tube 10. The entire needle tip 21 is sufficiently exposed.

The hub 12 is formed with a hole 13 into which a tip of a lever 67 described later is inserted. Although not shown, the hub 12 is provided with a fluid injection port that communicates with the inside of the trocar tube 10 so that gas or liquid can be injected into the body cavity, and further, a check valve is provided at this fluid injection port. May be provided to prevent leakage of gas or liquid in the body cavity.

The base end side of the protective member 4 is extended so as to be inserted into the grip portion 3, and further, the flange portion 45 protruding in the radial direction at the base end portion of the protective member 4 and the base end side wall of the grip portion 3. A coil-shaped spring 5 is inserted between the parts. The protection member 4 is biased toward the tip end by the spring 5.

The spring constant of the spring 5 is, as shown in FIG.
When the needle tip portion 21 is punctured by the abdominal wall 100 and the lock of the lock mechanism 6 is released, the covering portion 42 does not protrude from the tip end opening 23, and as shown in FIG.
00, and when the tip portion thereof is exposed in the abdominal cavity 101 for a predetermined length, it is preferable that the tip end portion 44 of the covering portion be set so as to project from the tip end opening 23, specifically, 400 to 600 g. It is preferably about the same.

The protective member 4 is provided inside the grip member 3.
A lock mechanism 6 for restricting the movement of the to the tip side is installed. The lock mechanism 6 is located near the tip of the locking member 61 and has a leaf spring-like portion formed on the outer periphery of the base end of the protection member 4, and projects from the inner surface of the gripping member 3. The formed pin 62, the housing 63, the lock release member 64 that can move in the housing 63, the spring 66 that is installed in the housing 63 and biases the lock release member 64 in the distal direction, and the lock release member 64. And a lever 67 made of, for example, a metal protruding toward the tip side of the. The unlocking member 64 is formed with an inclined surface 65 that can be locked with the tip of the locking member 61. Further, the tip of the lever 67 protrudes by a predetermined length from the opening 31 formed in the tip side wall portion of the grip member 3.

As shown in FIG. 2, when the puncture needle assembly 1 is not used, the tip of the locking member 61 is locked to the pin 62 and is locked by the spring 5 in a contracted state. The movement of the protective member 4 toward the distal end side is restricted against the power. At this time, the spring 66 is in a natural state (extended state).

On the other hand, when the puncture needle 2 is inserted deep into the trocar tube 10 to puncture the living tissue with the needle tip 21,
The gripping member 3 is gripped and pressed in the distal direction, but the needle tip 2
When the distal end surface of the gripping member 3 approaches or contacts the proximal end surface of the hub 12 due to the puncture resistance received by the lever 1, the distal end of the lever 67 abuts the bottom of the hole 13 and the lever 67 is pressed in the proximal direction, and the spring 66 is contracted and the lock release member 64 is moved in the proximal direction. Along with this movement, the tip of the locking member 61 comes into contact with the inclined surface 65 of the unlocking member 64, is pressed, and moves downward in FIG. Thereby, the locking member 6
The tip of 1 is disengaged from the pin 62 and unlocked, that is, the protection member 4 is movable to the tip side by the urging force of the spring 5. When the protection member 4 moves toward the tip side, the tip of the locking member 61 moves along the lower portion of the pin 62 in FIG.

In such a lock mechanism 6, the needle tip portion 21
Since the lock is released by the puncture resistance of No. 1, it is necessary to set the spring constant of the spring 66 to an appropriate level accordingly. In the case of puncturing the abdominal wall, from the tip 24 of the needle tip portion 1/3 to
It is preferable that the lock mechanism 6 be unlocked when about half the length is punctured into the abdominal wall 100, and therefore the force corresponding to the puncture resistance at this time (for example, 500).
The spring constant of the spring 66 is set so that the lock is released when (g or more) acts on the spring 66. Also,
If the spring constant of the spring 66 is in this range, it is possible to prevent the lock from being released due to a malfunction.

A plurality of such lock mechanisms 6 may be arranged at equal angular intervals in the circumferential direction of the protective member 4. Further, the release of the lock in the lock mechanism 6 is not limited to the one performed by the puncture resistance of the needle tip portion 21 described above, and, for example, a separate button (switch) for releasing the lock is provided on the grasping member 3, and this button is manually operated. Alternatively, the lock may be released by operating with.

A covering portion 42 is provided on the outer periphery of the base end portion of the protective member 4.
The stopper 7 is formed of a protrusion for restricting the maximum protruding length from the front end opening 23. Protective member 4
When the stopper 7 contacts the inner projecting portion 32 on the distal end side of the gripping member 3, the protective member 4 does not move further in the distal end direction.

The protective member 4 is provided inside the gripping member 3.
Has a retreat prevention mechanism 8 for preventing the retreat, that is, the movement toward the base end. This reverse prevention mechanism 8
Corresponds to a linear ratchet structure, and has a plurality of saw-shaped notches 81 formed on the outer periphery of the base end portion of the protection member 4.
And an elastic member 82 having at its tip a claw 83 capable of engaging one notch 81.

The contour of each notch 81 on the tip side is perpendicular to the central axis of the protective member 4, and the contour on the base end side is the protective member 4.
Is inclined at a predetermined angle (for example, 45 °) with respect to the central axis of the. The shape of the claw 83 also corresponds to the shape of the notch 81.

With the above-described structure, when the protective member 4 moves in the distal direction, the claw 83 slides along the inclination of the notch 81 on the base end side and successively climbs over the ridges between the notches 81. However, when the protection member 4 is moved in the proximal direction, the tip side of the claw 83 is locked to the tip side of the notch 81 to prevent the movement.

The notch 81 is provided so as to cover the entire movement range of the protective member 4, and has a function of preventing the protective member from retreating regardless of the length of protrusion of the covering portion 42 from the front end opening 23. It always works. Note that the above-described backward movement preventing mechanism 8 may be configured to be able to cancel its function, if necessary.

Further, the gripping member 3 is provided with a display means 9 for knowing the protruding length of the covering portion 42 from the tip end opening 23. As shown in FIG. 1, the display means 9 has a long hole 91 formed linearly in the gripping member 3 along the moving direction of the protection member 4, and a scale 92 displayed near the long hole 91. And a display projection 93 which is erected in the vicinity of the collar portion 45 of the protection member 4 and is movable in the long hole 91. The display projection 93 moves in the long hole 91 as the protective member 4 moves. By reading the position on the scale 92, the moving amount of the protective member 4, that is, the covering portion 4 is obtained.
It is possible to know the length of protrusion from the tip end opening 23 of No. 2.
Note that the scale 92 may indicate an absolute projection length from the tip end opening 23 of the covering portion 42 or a relative projection length (projection amount).

Next, the operation of the puncture needle assembly 1 will be described. When the puncture needle 2 is inserted into the trocar tube 10, the grasping member 3 is grasped by hand, and the needle tip 21 is punctured into the abdominal wall (living tissue) 100 as shown in FIG. The tip end surface of 3 contacts the base end surface of the hub 12, the tip end of the lever 67 abuts the bottom of the hole 13, the lever 67 is pressed in the base end direction, and the lock mechanism 6 is unlocked as described above. The protection member 4 is biased by the spring 5 toward the tip.

In this case, as shown in FIG. 5, when the apex 24 of the puncture needle 2 is inside the abdominal wall 100, the reaction force (resistance) that the covering portion 42 receives from the tissue of the abdominal wall 100 is large.
The tip portion 44 of the covering portion does not protrude from the tip opening 23, and therefore, the puncture action of the needle tip portion 21 is not hindered.

As the puncture progresses further, as shown in FIG. 6, the needle point portion 21 penetrates the abdominal wall 100, and the tip 24 thereof is abdominal wall 1.
When exposed to the abdominal cavity 101 side of No. 00, the reaction force received by the cover end portion 44 from the tissue of the abdominal wall 100 decreases, and the cover end portion 44 projects from the end opening 23 by the biasing force of the spring 5. The tip of the covering portion 44, which has been regulated by the inner surface of the puncture needle 2 until then, is released from the regulation due to this protrusion and returns to the shape curved toward the tip 24 side to coat the tip 24. In this way, the tip end 24 of the needle tip 21 is moved to the abdominal cavity 101.
When exposed inside, the tip 44 of the covering portion immediately covers the tip 24, so that the biological tissue (organ, etc.) near the abdominal wall is protected, that is, the tip 24 prevents damage to the organ and the like.

In the state shown in FIG. 6, since the reaction force received by the tissue of the abdominal wall 100 against the stepped portion 43 of the covering portion 42 is still large, the stepped portion 43 does not protrude from the distal end opening 23. I can't reach it. Therefore, the portion of the blade surface 22 located inside the abdominal wall is not covered by the covering portion 42, so that the puncture action of the needle tip portion 21 is not hindered.

When the puncture further progresses and as shown in FIG. 7, almost the entire needle tip portion 21 is exposed inside the abdominal cavity 101, the reaction force received by the tissue of the abdominal wall 100 by the covering portion 42 becomes almost zero, and the covering portion 42 is covered. Further protrudes to such an extent as to cover the blade surface 22 and protects organs and the like near the abdominal wall.

When the tip of the trocar tube 10 projects into the abdominal cavity 101 for a predetermined length, the puncture needle 2 is pulled out from the trocar tube 10 and the operation of penetrating the trocar tube 10 into the abdominal wall 100 is completed.

In the series of puncturing operations as described above, the change in the protruding length of the covering portion 42 can be confirmed by the display means 9. Further, since the maximum protrusion length of the covering portion 42 from the tip end opening 23 is regulated by the stopper 7, the covering portion 42 does not excessively protrude.

Further, even if the covering portion 42 that has once protruded is not pushed back to the base end side by the retreat prevention mechanism 8 even if it comes into contact with an organ or the like and is pressed to the base end side, for example, the organ etc. Can be safely protected.

Although the puncture needle assembly of the present invention has been described above with reference to the illustrated structural example, the present invention is not limited to this.

For example, the shape of the covering portion 42 and the protective member 4
Urging means for urging the lock mechanism 6, the lock mechanism 6, the backward movement prevention mechanism 8,
Each configuration of the display means 9 and the like may have the same operation and function different from those shown. Further, the lock mechanism 6, the stopper 7, the backward movement preventing mechanism 8, the display means 9
Etc. may be omitted as necessary.

Further, the deformation of the covering portion 42, which is represented by the bending of the covering portion distal end portion 44, is not limited to the above-described deformation caused by releasing the regulation of the natural bending in advance, but for example, the wire. By the pulling operation of
It is also possible to give the 2 deformation such as bending and bending.

[0061]

As described above, according to the puncture needle assembly of the present invention, when the needle tip portion of the puncture needle punctures and penetrates the living tissue, the protection member is covered according to the progress of the puncture. The part sequentially projects from the tip opening of the needle tip and deforms to cover at least the vicinity of the tip of the needle tip, so it is possible to reliably damage the organs and the like near the lower part of the punctured living tissue by the tip of the needle tip. Prevented and highly safe. In particular, the above effect is effectively exhibited even when the puncture needle has a high puncture speed, or when the punctured living tissue is close to or in close contact with an organ or the like below it.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view showing a configuration example of a puncture needle assembly of the present invention.

FIG. 2 is a vertical sectional view showing a configuration example of a puncture needle assembly of the present invention.

FIG. 3 is a perspective view showing the configuration of the tip portion of the puncture needle assembly of the present invention.

FIG. 4 is a vertical cross-sectional view showing the configuration of the tip portion of the puncture needle assembly of the present invention.

FIG. 5 is a cross-sectional view showing the operation of the puncture needle assembly of the present invention.

FIG. 6 is a cross-sectional view showing the operation of the puncture needle assembly of the present invention.

FIG. 7 is a cross-sectional view showing the operation of the puncture needle assembly of the present invention.

FIG. 8 is a cross-sectional view showing a state of laparoscopic surgery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Puncture needle assembly 2 Puncture needle 21 Needle tip part 22 Blade surface 23 Tip opening 24 Tip 3 Grasping part 31 Opening 32 Inner protrusion 4 Protective member 41 Protective member main body 42 Cover part 43 Step part 44 Cover part Tip part 45 Collar part 5 Spring 6 Lock Mechanism 61 Locking Member 62 Pin 63 Housing 64 Lock Release Member 65 Inclined Surface 66 Spring 67 Lever 7 Stopper 8 Backward Prevention Mechanism 81 Notch 81 Notch 82 Elastic Member 83 Claw 9 Display Means 91 Long Hole 92 Scale 93 For Display Protrusion 10 Trocar tube 11 Taper 12 Hub 13 Hole 100 Abdominal wall 101 Abdominal cavity 102 Small camera 103 Monitor image 104 Forceps 105 Scissors 106 Electric knife

Claims (1)

[Claims] 1. A puncture needle assembly used for guiding a tubular body penetrating a biological tissue, comprising: a hollow puncture needle having a needle tip at its tip, and a puncture needle movable in the axial direction within the puncture needle. The protective member is inserted and has an elastically deformable coating portion, and has a biasing means for biasing the protective member toward the needle tip portion side, and when the biopsy tissue is punctured, the coating Department is
A puncture needle assembly, wherein the puncture needle assembly is configured to project from the tip opening of the puncture needle and deform to cover at least the vicinity of the tip of the needle tip as the reaction force received from living tissue decreases.