JP2004275594A - Catheter with needle projection adjusting mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catheter which can accurately adjust projection of a needle on its tip. <P>SOLUTION: The catheter comprises a sheath part 20 with a lumen to dilate inside, a tip part 32 which is set slidably to the lumen in the sheath part 20 and can project from an apex part 22 of the sheath part 20, a threading member 30 having a base part to which a liquid composition is supplied and a lumen which dilates inside from the base part to the tip part 32 and the liquid composition is introduced into, a needle 33 set on the tip part 32 of the threading member 30 and connected to the lumen in the threading member 30, and an adjusting mechanism for adjusting the projection of the needle 33 from the end part 22 of the sheath part 20. The adjusting mechanism has a stopping mechanism set in the lumen in the apex part 22 of the sheath part 20 to stop moving of the tip part 32 of the threading member 30 at a predetermined position, and an operation part 40 at hand having a changing mechanism to change the predetermined position and a driving mechanism to move the threading member 30 in a longitudinal direction to the sheath part 20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a catheter for injecting a liquid composition into a target site.
[0002]
[Prior art]
Conventional catheters have a stopper at the distal end of a tube that regulates the amount of protrusion of the injection needle (for example, see Patent Documents 1 to 5).
[0003]
In addition, the injection needle has an adjustment mechanism that adjusts the amount of protrusion of the injection needle from the distal end of the sheath by moving the insertion member disposed at the distal end in the longitudinal direction with respect to the sheath. (See, for example, Patent Documents 7 to 9).
[0004]
[Patent Document 1]
JP-A-62-127030
[Patent Document 2]
Japanese Patent Publication No. 5-030460
[Patent Document 3]
JP-A-10-85331
[Patent Document 4]
U.S. Pat. No. 6,336,915
[Patent Document 5]
U.S. Pat. No. 5,785,689
[Patent Document 6]
Patent No. 2944900
[Patent Document 7]
JP-A-9-75455
[Patent Document 8]
JP 2001-178828 A
[0005]
[Problems to be solved by the invention]
However, the stoppers described in Patent Documents 1 to 5 can prevent a certain amount or more of the injection needle from protruding, but cannot change the protruding amount.
[0006]
Further, since the adjustment mechanisms described in Patent Documents 6 to 8 are arranged at the proximal end of the catheter, for example, when the catheter is curved, the sheath and the insertion member expand and contract, and the operation at the proximal end is performed. May not be accurately transmitted to the distal end portion, and there is a possibility that the protrusion amount of the injection needle may be deviated.
[0007]
Thus, for example, when injecting a therapeutic composition into heart tissue, if the injection needle projects more than expected, the injection needle may penetrate the heart wall. Further, when the puncture depth of the injection needle is shallower than expected and the injection needle is not reliably punctured into the target tissue, the therapeutic composition may leak out of the target tissue. Further, it is difficult to apply the present invention to a treatment that requires an effective insertion of an injection needle accurately at a target depth of an affected part.
[0008]
The present invention has been made in order to solve such a conventional problem, and provides a catheter capable of accurately adjusting an amount of protrusion of an injection needle at a distal end portion, and an injection method using the catheter. The purpose is to:
[0009]
[Means for Solving the Problems]
The present invention for achieving the above object is configured as follows.
[0010]
(1) a sheath having a lumen extending inside;
A distal end portion slidably disposed in the lumen of the sheath portion and protrudable from a distal end portion of the sheath portion, a base end portion to which a liquid composition is supplied, and an inside portion extending from the base end portion to the distal end portion. Extending, a penetrating member having a lumen into which the liquid composition is introduced,
An injection needle disposed at a distal end of the insertion member and communicating with a lumen of the insertion member;
An adjusting mechanism for adjusting the amount of protrusion of the injection needle from the distal end of the sheath,
The adjustment mechanism includes:
A stop mechanism that is disposed in the lumen at the distal end of the sheath and that stops the movement of the distal end of the insertion member at a predetermined position,
A hand operating unit having a changing mechanism for changing the predetermined position and a driving mechanism for moving the insertion member in the longitudinal direction with respect to the sheath;
A catheter characterized by the above-mentioned.
[0011]
(2) The restraining mechanism has a fixed portion disposed on a lumen at a distal end portion of the sheath portion, and a movable portion disposed on the insertion member.
The catheter according to (1), wherein the changing mechanism changes the predetermined position by adjusting a position at which the fixed portion and the movable portion abut.
[0012]
(3) The catheter according to (2), wherein the changing mechanism changes a position where the fixed portion and the movable portion come into contact with each other by rotating the insertion member.
[0013]
(4) The target site into which the liquid composition is injected is a diseased part in a living body, and the liquid composition has a therapeutic composition. Item 2. The catheter according to item 1.
[0014]
(5) The catheter according to (4), wherein the affected part in the living body is a heart tissue.
[0015]
(6) The catheter according to (4) or (5), wherein the therapeutic composition is a composition containing a nucleic acid, a protein, or a cell.
Nucleic acid
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view of a catheter according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view for explaining a hand operation unit of the catheter shown in FIG.
[0016]
The catheter 10 includes a sheath 20, an insertion member 30, an injection needle 33, and an injection needle protrusion amount adjustment mechanism having a hand operation unit 40 and a stopping mechanism.
[0017]
The sheath 20 is a hollow substantially cylindrical member having a lumen 21 extending inside, and the insertion member 30 extends inside the lumen 21 so as to be slidable. The shape of the sheath 20 is not particularly limited to a cylindrical shape.
[0018]
Although the material of the sheath portion 20 is not particularly limited, polyolefin, olefin-based elastomer, polyester, soft polyvinyl chloride, polyurethane, urethane-based elastomer, polyamide, amide-based elastomer, polytetrafluoroethylene, fluororesin elastomer, polyimide, ethylene- Polymer materials such as vinyl acetate copolymer and silicone rubber can be used.
[0019]
The polyolefin is, for example, polypropylene or polyethylene. The olefin-based elastomer is, for example, a polyethylene elastomer or a polypropylene elastomer. The amide-based elastomer is, for example, a polyamide elastomer.
[0020]
When the sheath portion 20 is formed of a synthetic resin, the rigidity can be improved by using, for example, a pipe made of a superelastic alloy, an embedded coil or an embedded mesh made of metal.
[0021]
The insertion member 30 has a hollow, substantially cylindrical shape, penetrates the hand operation unit 40, and is slidably disposed on the lumen 21 of the sheath 20. The insertion member 30 has a distal end portion 32 that can protrude from the distal end portion of the sheath portion 20, a base end portion 35 to which the liquid composition is supplied, and an inside extending from the base end portion 35 to the distal end portion 32. And a lumen 31 into which an object is introduced. The liquid composition is, for example, a therapeutic composition containing nucleic acids, proteins, or cells. The shape of the insertion member 30 is not particularly limited to a cylindrical shape.
[0022]
The material of the insertion member 30 is not particularly limited, and examples thereof include a metal, a polymer material having relatively high rigidity, and a combination of these materials as appropriate. For example, the metal is a stainless steel, a Ni-Ti alloy, a Cu-Zn alloy, a cobalt alloy, or tantalum. For example, the polymer material is polyamide, polyimide, ultra-high molecular weight polyethylene, polypropylene, or fluororesin.
[0023]
The outer diameter of the insertion member 30 is not particularly limited as long as it can slide inside the lumen 21 of the sheath 20, but is preferably 0.3 to 0.7 mm. The inner diameter of the insertion member 30 is not particularly limited, but is preferably 0.15 to 0.55 mm.
[0024]
The injection needle 33 is arranged at the distal end portion 32 of the insertion member 30 and communicates with the lumen 31. Therefore, the injection needle 33 can inject the liquid composition flowing inside the lumen 31 of the insertion member 30. The target site into which the liquid composition is injected is a diseased part in a living body, for example, a heart tissue such as a cardiac ischemic part or a peripheral part thereof.
[0025]
The injection needle 33 can be formed, for example, by forming a beveled blade surface by performing a needle attaching process on the distal end portion 32 or by attaching a separate injection needle.
[0026]
The hand operation unit 40 includes a distal end portion 41 to which the proximal end portion 23 of the sheath portion 20 is connected, an injection needle control unit 44 through which the insertion member 30 penetrates the center, and a knob 45 of the injection needle control unit 44. And a window 43 for operating the. The insertion member 30 is fixed to the injection needle control unit 44.
[0027]
The injection needle control unit 44 has a substantially cylindrical shape, and is supported inside the hand operation unit 40 so as to be movable and rotatable in the longitudinal direction. Therefore, the insertion member 30 can be moved in the longitudinal direction (the distal direction or the proximal direction) with respect to the sheath portion 20 by moving the injection needle control unit 44 in the longitudinal direction. Further, as will be described later, by rotating the injection needle control unit 44, the stopping mechanism can be controlled.
[0028]
The hand operation unit 40 has O-rings 48 and 49. The O-ring 48 is disposed between the frame of the hand operation unit 40 and the injection needle control unit 44, and regulates the operation of the injection needle control unit 44 with an appropriate strength. The O-ring 49 is disposed at the distal end portion 41 between the outer surface of the insertion member 30 and the inner surface of the proximal end portion 23 of the sheath portion 20, and seals the inside of the hand operation portion 40. Prevent inflow.
[0029]
Note that the base end 35 of the insertion member 30 extends from the base end 42 of the hand operation unit 40, and a hub 36 for injecting the therapeutic composition is arranged. For example, a syringe is connected to the hub 36.
[0030]
FIG. 3 is a cross-sectional view for explaining a stopping mechanism of the catheter shown in FIG. 1 and shows a forward stop position of a movable part of the stopping mechanism. FIG. FIG. 5 is a cross-sectional view for explaining the stop position, FIG. 5 is a cross-sectional view for explaining a change in the forward stop position of the movable portion shown in FIG. 3 after rotating the insertion member of the catheter, and FIG. FIG. 6 is a cross-sectional view for explaining a retracted stop position of the movable unit shown in FIG. 5.
[0031]
The stopping mechanism according to the first embodiment includes a stopping device 50. The stop device 50 is disposed in the lumen 21 of the distal end portion 22 of the sheath portion 20 and is used to stop the movement of the distal end portion 32 of the insertion member 30 at a predetermined position, and adjusts the amount of protrusion of the injection needle 33. Having. More specifically, the restraining device 50 includes a fixed part 60, a shaft part 70, and a movable part 80.
[0032]
The fixing portion 60 has a hollow cylindrical shape fixed to the inner peripheral surface of the lumen 21, and has an elongated rectangular concave portion 65 formed to extend in the distal direction. The method of fixing the fixing portion 60 is not particularly limited, and for example, it is possible to apply adhesion.
[0033]
The shaft portion 70 has a substantially columnar shape, and the distal end portion 32 of the insertion member 30 penetrates a central portion thereof, and is fixed to the distal end portion 32. Therefore, the shaft 70 is driven by the operation of the insertion member 30. The method of fixing the shaft 70 is not particularly limited, and for example, it is possible to apply adhesion. A screw groove 71 is formed on the outer periphery of the shaft portion 70.
[0034]
The movable portion 80 has a substantially columnar shape, has a through hole at the center corresponding to the outer peripheral shape of the shaft portion 70, and accommodates the shaft portion 70 in a nested manner. A screw groove 81 corresponding to the screw groove 71 of the shaft portion 70 is formed on the inner periphery of the through hole.
[0035]
Therefore, when the shaft 70 is rotated, the shaft 70 moves inside the through hole of the movable section 80. In addition, a flange portion having a diameter larger than the through hole of the movable portion 80 is formed at the base end portion and the distal end portion of the shaft portion 70, and the movable range of the shaft portion 70 is limited.
[0036]
Further, the movable portion 80 has an elongated rectangular convex portion 85 formed to extend in the distal direction. The size of the convex portion 85 is set so as to be slidable in the concave portion 65 of the fixed portion 60. In addition, it is also possible to form a concave part in the movable part 80 and to form a convex part in the fixed part 60. In addition, the protrusion 85 is not limited to a continuous shape, and may be configured by, for example, a plurality of protrusions arranged linearly.
[0037]
The movable section 80 cannot rotate because the movement of the convex section 85 is restricted by the side surface of the concave section 65 of the fixed section 60. Further, the movement of the movable portion 80 in the longitudinal direction is restricted by the protrusions 85 abutting on the end surfaces 66 and 67 of the recesses 65 of the fixed portion 60.
[0038]
Therefore, when the injection needle control unit 44 of the hand operation unit 40 is advanced and the insertion member 30 fixed to the injection needle control unit 44 is moved in the distal direction with respect to the sheath portion 20, the distal end side of the convex portion 85 The end surface 86 abuts on the end surface 66 on the tip side of the concave portion 65, and the movable portion 80 reaches the forward stop position (see FIG. 3). That is, since the movable portion 80 is fixed to the distal end portion 32 of the insertion member 30, the distal end movement of the distal end portion 32 of the insertion member 30 is stopped at the predetermined position.
[0039]
On the other hand, when the injection needle control unit 44 of the hand operation unit 40 is retracted and the insertion member 30 is moved in the proximal direction with respect to the sheath portion 20, the proximal end surface 87 of the convex portion 85 is The movable portion 80 comes into contact with the end surface 67 on the end side to reach the retraction stop position (see FIG. 4). That is, the movement of the distal end portion 32 of the insertion member 30 in the proximal direction is stopped at the predetermined position.
[0040]
Therefore, since the movement of the distal end portion 32 of the insertion member 30 is stopped at the predetermined position, the amount of projection of the injection needle 33 takes an accurate value. In addition, the injection needle 33 is housed inside the distal end portion 22 of the sheath portion 20 at the retracted stop position.
[0041]
When the injection needle control unit 44 of the hand operation unit 40 is rotated using the knob 45, the insertion member 30 fixed to the injection needle control unit 44 is driven to rotate, and as a result, the distal end of the insertion member 30 is rotated. The shaft 70 fixed to 32 rotates.
[0042]
Since the convex portion 85 of the movable portion 80 disposed outside the shaft portion 70 is inserted into the concave portion 65 of the fixed portion 60, the rotation of the movable portion 80 is restricted. Therefore, the shaft portion 70 moves in the longitudinal direction while rotating with respect to the movable portion 80 by the action of the screw grooves 71 and 81.
[0043]
That is, the positional relationship between the shaft portion 70 to which the distal end portion 32 of the insertion member 30 is fixed and the movable portion 80 changes, and the distance between the convex portion 85 of the movable portion 80 and the injection needle 33 changes. Accordingly, the amount of protrusion of the injection needle 33 at the forward stop position where the end surface 86 on the distal end side of the convex portion 85 and the end surface 66 on the distal end side of the concave portion 65 abut is adjusted.
[0044]
For example, as shown in FIG. 5, when the shaft 70 moves in the proximal direction with respect to the movable part 80, the amount of protrusion of the distal end 32 of the insertion member 30 depends on the positional relationship shown in FIG. 3. It becomes smaller than the amount of protrusion.
[0045]
When the injection needle control unit 44 of the hand operation unit 40 is retracted and the insertion member 30 is moved in the proximal direction with respect to the sheath portion 20, the proximal end surface 87 of the convex portion 85 is The movable portion 80 reaches the retraction stop position, and the injection needle 33 of the distal end portion 32 of the insertion member 30 is housed inside the distal end portion 22 of the sheath portion 20 (FIG. 6). reference).
[0046]
As described above, the hand operation unit 40 moves the insertion member 30 in the longitudinal direction with respect to the sheath 20 and the change mechanism for changing the predetermined position where the movement of the distal end portion 32 of the insertion member 30 is restricted. And a drive mechanism. The change mechanism changes the predetermined position by rotating the insertion member 30 to adjust the position where the fixed portion 60 and the movable portion 80 come into contact with each other.
[0047]
The material of the restraining device 50 is not particularly limited, but may be a metal, a relatively high-rigidity polymer material, or a combination of these materials as appropriate. For example, the metal is a stainless steel, a NiTi alloy, a Cu-Zn alloy, a cobalt alloy, or tantalum. The polymer material is polyamide, polyimide, ultra-high molecular weight polyethylene, polypropylene, or fluororesin.
[0048]
Next, a method of using the catheter 10 when injecting a therapeutic composition into a diseased part in a living body, for example, a heart tissue, will be described.
[0049]
First, a syringe is connected to the hub 36 arranged at the base end 35 of the insertion member 30, and priming with the therapeutic composition is performed.
[0050]
Thereafter, the guiding catheter 10 is guided using the guiding catheter, and the distal end portion 22 of the sheath 20 is pressed against the target site of the heart tissue. Then, by rotating the knob 45 of the injection needle control unit 44, the setting of the stopping device 50 is changed, and the protrusion amount of the injection needle 33 is adjusted to a necessary value. The protrusion amount is determined in advance by measuring the thickness of the heart tissue by echocardiography.
[0051]
Next, the injection needle control unit 44 is moved toward the distal end side 41 of the hand operation unit 40 so that the injection needle 33 is projected from the distal end portion 22 of the sheath 20. At this time, for example, even if the catheter 10 is curved or the sheath 20 and the insertion member 30 expand and contract, the amount of protrusion of the injection needle 33 is accurately adjusted by the restraining device 50. At the puncture depth, the heart wall is punctured. Therefore, it is possible to reliably prevent the injection needle from protruding more than expected, and prevent the injection needle from penetrating the heart wall and puncturing the affected part at an unintended depth.
[0052]
Thereafter, the therapeutic composition is injected from the syringe via the hub 36 arranged at the base end 35 of the insertion member 30. At this time, as described above, the injection needle is accurately positioned at the target puncture depth, so that the therapeutic composition is prevented from leaking out of the target tissue. After the injection is completed, the injection needle 33 is accommodated in the lumen 21 of the distal end portion 22 of the sheath portion 20 by moving the injection needle control portion 44 toward the proximal end side 42 of the hand operation portion 40.
[0053]
Then, the catheter 10 is moved toward the next target part of the heart tissue, the setting of the restraint device 50 is changed as necessary, the protrusion amount of the injection needle 33 is adjusted, and the above operation is repeated.
[0054]
Note that the tip portion 22 of the sheath portion 20 is preferably formed using a resin containing an X-ray opaque material. In this case, the distal end of the sheath 20 has X-ray contrast properties and functions as an X-ray contrast marker. Therefore, the catheter 10 can be guided while confirming the position of the distal end portion 22 of the sheath portion 20 under fluoroscopy.
[0055]
The radiopaque material is, for example, a powder of tantalum, tungsten carbide, bismuth oxide, barium sulfate, platinum or an alloy thereof, or a cobalt alloy.
[0056]
The injection method using the catheter 10 can be applied to gene therapy or cell therapy.
[0057]
Gene therapy is, for example, a method for treating heart disease, and injecting the gene therapy composition with a syringe needle built into a catheter is preferable in that it is minimally invasive.
[0058]
Cell therapy is, for example, a method of transplanting new cells (cardiomyocytes, skeletal myoblasts, smooth muscle cells, bone marrow-derived cells) from the outside to improve cardiac function. Therefore, an injection needle built into a catheter can be applied, for example, to implant bone marrow-derived cells at and around an infarct site.
[0059]
As described above, the catheter according to Embodiment 1 of the present invention is disposed in the lumen at the distal end of the sheath, and controls the movement of the distal end of the insertion member at a predetermined position. And a hand operating portion having a driving mechanism for moving the insertion member in the longitudinal direction with respect to the sheath portion with the changing mechanism for changing the length of the needle. The protrusion amount of the needle can be adjusted accurately. That is, it is possible to provide a catheter that can accurately adjust the amount of protrusion of the injection needle at the distal end.
[0060]
In addition, when the catheter is used for an injection method, it is possible to provide an injection method that can accurately adjust the amount of protrusion of the injection needle at the distal end portion, for example, by adjusting the amount of protrusion of the injection needle. The target site can be punctured and the liquid composition can be injected.
[0061]
FIG. 7 is a cross-sectional view for explaining a stopping mechanism of the catheter according to Embodiment 2 of the present invention, and shows a forward stopping position of a movable portion of the stopping mechanism. FIG. 8 is shown in FIG. FIG. 9 is a cross-sectional view for explaining a retreat stop position of the movable section, FIG. 9 is a cross-sectional view for explaining a change in a forward stop position of the movable section shown in FIG. 7 after rotating the insertion member of the catheter, FIG. 10 is a cross-sectional view for explaining the retracted stop position of the movable portion shown in FIG.
[0062]
The catheter according to the second embodiment of the present invention is generally different from the first embodiment in that the amount of protrusion of the injection needle can be adjusted in two stages and the structure of the stopping mechanism is simplified.
[0063]
More specifically, the restraining mechanism has a fixed portion 160 fixed to the lumen 123 of the distal end portion 122 of the sheath portion 120, and a movable portion 180 fixed to the distal end portion 132 of the insertion member 130. The fixing portion 160 has a hollow cylindrical frame 161, a distal stopper 165 fixed to the distal end of the frame 161, and a proximal stopper 168 fixed to the proximal end of the frame 161.
[0064]
The distal end stopper 165 is an L-shaped member having a cylindrical portion and a semi-cylindrical portion protruding from the cylindrical portion, and has a through hole through which the insertion member 130 is slidable.
[0065]
The base end stopper 168 is a ring-shaped member and has a through hole through which the insertion member 130 can slide. The inner diameter of the through hole is smaller than the outer diameter of the movable part 180. Therefore, the proximal end stopper 168 defines the retraction stop position of the movable portion 180. That is, the movement of the distal end 132 of the insertion member 130 in the proximal direction is restricted at the position where the proximal stopper 168 is disposed. Note that the proximal stopper 168 can be directly fixed to the sheath 120.
[0066]
Instead of providing the proximal stopper 168, the inner diameter of the sheath 120 is reduced at a portion adjacent to the proximal end of the frame 161, thereby serving as a stopper for restricting movement of the insertion member 130 in the proximal direction. You may let it.
[0067]
The movable part 180 has substantially the same shape as the tip stopper 165 except that the diameter is slightly smaller in order to be slidable inside the frame 161 of the fixed part 160, and is extended from the cylindrical part and the cylindrical part. And is fixed to the insertion member 130 through the through-hole.
[0068]
Therefore, when the semi-cylindrical portion of the movable portion 180 and the semi-cylindrical portion of the distal end stopper 165 are alternately arranged to move the insertion member 130 in the distal direction, the movable portion 180 and the distal end stopper 165 are fitted. Then, the movable portion 180 reaches the forward stop position (see FIG. 7).
[0069]
On the other hand, when the insertion member 130 is moved in the proximal direction with respect to the sheath portion 120, the proximal end of the movable portion 180 comes into contact with the proximal stopper 168, and the movable portion 180 reaches the retraction stop position (FIG. 8). Therefore, since the movement of the movable portion 180 is limited to the range from the forward stop position shown in FIG. 7 to the retreat stop position shown in FIG. 8, the movement of the distal end portion 132 of the insertion member 130 is performed at a predetermined position. Will be suspended. That is, the protrusion amount of the injection needle 133 takes an accurate value.
[0070]
In addition, the injection needle control unit (the insertion member 130) is rotated, and the position of the semi-cylindrical portion of the movable portion 180 fixed to the insertion member 130 and the semi-cylindrical portion of the distal end stopper 165 are aligned. To change the insertion member 130 in the distal direction, the semi-cylindrical portion of the movable portion 180 and the semi-cylindrical portion of the distal end stopper 165 abut, and the movable portion 180 reaches the forward stop position (see FIG. 9). .
[0071]
On the other hand, when the insertion member 130 is moved in the proximal direction with respect to the sheath portion 120, the proximal end of the movable portion 180 comes into contact with the proximal stopper 168, and the movable portion 180 reaches the retraction stop position (FIG. 10).
[0072]
Therefore, since the movement of the movable portion 180 is limited to the range from the forward stop position shown in FIG. 9 to the retreat stop position shown in FIG. 10, the amount of protrusion of the injection needle 133 is shown in FIGS. Shorter than the settings shown.
[0073]
As described above, in the catheter according to Embodiment 2 of the present invention, the protrusion amount of the injection needle can be adjusted in two stages, and the structure of the stopping mechanism is simplified. Reference numeral 121 denotes a lumen of the sheath 120, and reference numeral 131 denotes a lumen of the insertion member 130.
[0074]
FIG. 11 is a cross-sectional view for explaining a catheter stopping mechanism according to Embodiment 3 of the present invention, and shows a forward stopping position of a movable portion of the stopping mechanism. FIG. 12 shows a catheter insertion member. FIG. 12 is a cross-sectional view for explaining a change in a forward stop position of the movable unit shown in FIG. 11 after being rotated.
[0075]
The catheter according to the third embodiment of the present invention is generally different from the second embodiment in the shapes of the distal end stopper and the movable portion of the restraining mechanism.
[0076]
More specifically, the tip stopper 265 has a tapered shape in which one end of a cylindrical body is cut obliquely, and has a cylindrical portion, a tapered portion extending from the cylindrical portion and protruding therefrom, and a through-hole through which the insertion member 230 is slidable. And
[0077]
The movable part 280 has substantially the same shape as the tip stopper 265 except that the diameter is slightly smaller and the end face of the tapered part is also small, so that the movable part 280 can slide inside the frame 261 of the fixed part 260. It is fixed to the insertion member 230 through the through hole.
[0078]
Therefore, when the tapered portion of the movable portion 280 and the tapered portion of the distal end stopper 265 are alternately arranged to move the insertion member 230 in the distal direction, the inclined surface of the tapered portion of the movable portion 280 and the tapered portion of the distal end stopper 265 are moved. The movable portion 280 comes into contact with the slope of the tapered portion to reach the forward stop position (see FIG. 11).
[0079]
On the other hand, the injection needle control unit (the insertion member 230) is rotated, and the position is changed so that the end surface of the tapered portion of the movable portion 280 and the end surface of the tapered portion of the distal end stopper 265 are arranged on the same line. Is moved in the distal direction, the end surface of the tapered portion of the movable portion 280 comes into contact with the end surface of the tapered portion of the distal stopper 265, and the movable portion 280 reaches the forward stop position (see FIG. 12). Therefore, the movement of the movable part 280 is shorter than the setting shown in FIG. 11, and the amount of protrusion of the injection needle 233 arranged at the distal end 232 of the insertion member 230 from the distal end 222 of the sheath 220 is Change.
[0080]
As described above, in the catheter according to Embodiment 3 of the present invention, similarly to Embodiment 2, the protrusion amount of the injection needle can be adjusted in two stages, and the structure of the stopping mechanism is simplified. Reference numeral 221 indicates a lumen of the sheath 220, reference numeral 231 indicates a lumen of the insertion member 230, and reference numeral 268 indicates a proximal stopper.
[0081]
【The invention's effect】
According to the present invention described above, the stop mechanism for stopping the movement of the distal end of the insertion member at a predetermined position, which is disposed in the lumen at the distal end of the sheath, and a change mechanism for changing the predetermined position, Since there is provided an injection needle protrusion amount adjustment mechanism having a hand operating portion having a drive mechanism for moving the insertion member in the longitudinal direction with respect to the sheath portion, the protrusion amount of the injection needle at the distal end portion is accurately adjusted. be able to. That is, it is possible to provide a catheter that can accurately adjust the amount of protrusion of the injection needle at the distal end.
[0082]
In addition, when the catheter is used for an injection method, it is possible to provide an injection method that can accurately adjust the amount of protrusion of the injection needle at the distal end portion, for example, by adjusting the amount of protrusion of the injection needle. The target site can be punctured and the liquid composition can be injected.
[Brief description of the drawings]
FIG. 1 is a plan view of a catheter according to Embodiment 1 of the present invention.
FIG. 2 is a cross-sectional view for explaining a hand operation unit of the catheter shown in FIG.
FIG. 3 is a cross-sectional view for explaining a restraining mechanism of the catheter shown in FIG. 1, showing a forward restraining position of a movable portion of the restraining mechanism.
FIG. 4 is a cross-sectional view for explaining a retracted stop position of the movable unit shown in FIG. 3;
FIG. 5 is a cross-sectional view for explaining a change in a forward stop position of the movable unit shown in FIG. 3 after the insertion member of the catheter is rotated.
FIG. 6 is a cross-sectional view for explaining a retracted stop position of the movable portion shown in FIG.
FIG. 7 is a cross-sectional view for explaining a blocking mechanism of a catheter according to Embodiment 2 of the present invention, and shows a forward blocking position of a movable portion of the blocking mechanism.
FIG. 8 is a cross-sectional view for explaining a retracted stop position of the movable portion shown in FIG. 7;
FIG. 9 is a cross-sectional view for explaining a change in a forward-restricted position of the movable portion shown in FIG. 7 after the insertion member of the catheter is rotated.
FIG. 10 is a cross-sectional view for explaining a retracted stop position of the movable portion shown in FIG. 9;
FIG. 11 is a cross-sectional view for explaining a blocking mechanism of a catheter according to Embodiment 3 of the present invention, and shows a forward blocking position of a movable portion of the blocking mechanism.
FIG. 12 is a cross-sectional view for explaining a change in a forward-restricted position of the movable portion shown in FIG. 11 after the insertion member of the catheter is rotated.
[Explanation of symbols]
10 ... catheter,
20 ... sheath,
21 ... lumens,
22 ... the tip,
23 ... base end,
30 ... insertion member,
31 ... lumens,
32 ... tip,
33 ... injection needle,
35 ... proximal end,
36 ... Hub,
40 ... hand operation part,
41 ... tip,
42 ... base end,
43 ... window,
44: injection needle control unit,
45 ... knob,
48… O-ring,
49 ... O-ring,
50 ... stop device,
60 fixed part,
65 ... recess,
66, 67 ... end face,
70 ... shaft part,
71 ... screw groove,
80 ... movable part,
81 ... screw groove,
85 ... convex part,
86, 87 ... end face,
120 ... sheath,
121 ... lumens,
122 ... tip,
130 ... insertion member,
131 ... lumens,
132 ... tip,
133 ... injection needle,
160 ... fixed part,
161 ... frame,
165: Tip stopper,
168: base end stopper,
180 ... movable part,
220 ... sheath part,
221 ... lumens,
222 ... tip part,
230 ... insertion member,
231 ... lumens,
232: tip,
233: injection needle,
260 fixed part,
261, a frame,
265: Tip stopper,
268: base end stopper,
280 movable part.

Claims (6)

A sheath having a lumen extending the inside,
A distal end portion slidably disposed in the lumen of the sheath portion and protrudable from a distal end portion of the sheath portion, a base end portion to which a liquid composition is supplied, and an inside portion extending from the base end portion to the distal end portion. Extending, a penetrating member having a lumen into which the liquid composition is introduced,
An injection needle disposed at a distal end of the insertion member and communicating with a lumen of the insertion member;
An adjusting mechanism for adjusting the amount of protrusion of the injection needle from the distal end of the sheath,
The adjustment mechanism includes:
A stop mechanism that is disposed in the lumen at the distal end of the sheath and that stops the movement of the distal end of the insertion member at a predetermined position,
A catheter comprising: a change mechanism for changing the predetermined position; and a hand operation unit having a drive mechanism for moving the insertion member in a longitudinal direction with respect to the sheath. The stopping mechanism has a fixed portion disposed on a lumen at a distal end portion of the sheath portion, and a movable portion disposed on the insertion member,
The catheter according to claim 1, wherein the change mechanism changes the predetermined position by adjusting a position where the fixed portion and the movable portion abut. The catheter according to claim 2, wherein the changing mechanism changes a position where the fixed portion and the movable portion come into contact with each other by rotating the insertion member. The catheter according to any one of claims 1 to 3, wherein the target site into which the liquid composition is injected is an affected part in a living body, and the liquid composition has a therapeutic composition. . The catheter according to claim 4, wherein the affected part in the living body is heart tissue. The catheter according to claim 4 or 5, wherein the therapeutic composition is a composition containing a nucleic acid, a protein, or a cell.

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