JP2005319170A - Catheter with excellent controllability on quantity of needle puncture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catheter with an excellent controllability on the quantity of puncture of a needle. <P>SOLUTION: The catheter comprises a sheath part 170 with a lumen 171 extending in the interior, an insertion member 180 slidably disposed in the lumen 171 of the sheath part 170, a syringe needle 190 disposed at the distal end 182 of the insertion member 180 to project from the distal end 172 of the sheath part 170, and a spring member 110 disposed in the gap formed between the lumen 171 of the sheath part 170 and the outer periphery of the insertion member 180 in such a way as to surround the outer periphery of the insertion member 180. The spring member 110 has a large-diameter region 111 and a small-diameter region 112 with different outer diameters. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a catheter.

A conventional catheter has a sheath portion having a lumen extending inside, an insertion member that is slidably disposed in the lumen of the sheath portion, and an injection needle that is disposed at a distal end portion of the insertion member. The amount of protrusion of the injection needle is adjusted by controlling the amount of movement of the proximal end (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 3-15081

  However, when the lesion site in a living body, for example, a heart tissue or the like, is a target site, it is rare that a linear approach can be performed from the catheter introduction site to the target site. It is necessary to approach the curved sheath.

  Since the curvature of the sheath part causes an axial shift of the insertion member disposed inside, even if the movement amount of the proximal end portion of the insertion member is constant, the protruding amount of the injection needle changes. Therefore, it is difficult to control the needle stick amount, and there is a problem in controllability with respect to the needle stick amount.

  The present invention has been made to solve such a conventional problem, and an object thereof is to provide a catheter having good controllability with respect to the needle stick amount.

  To achieve the above object, the present invention is configured as follows.

(1) a sheath having a lumen extending inside;
An insertion member slidably disposed in the lumen of the sheath,
An injection needle that is disposed at the distal end of the insertion member and can protrude from the distal end of the sheath;
In a gap formed between the lumen of the sheath portion and the outer periphery of the insertion member, a spring member arranged so as to surround the outer periphery of the insertion member,
The catheter, wherein the spring member has an enlarged diameter part and a reduced diameter part having different outer diameters.

  (2) The catheter according to (1), wherein the spring member has a spiral shape.

  (3) The outer diameter of the enlarged diameter portion is substantially the same as the inner diameter of the lumen of the sheath portion, and the inner diameter of the reduced diameter portion is substantially the same as the outer diameter of the insertion member. The catheter according to (1) or (2) above.

  (4) The catheter according to any one of (1) to (3), wherein a plurality of the diameter-expanded portions and the diameter-reduced portions are alternately arranged.

  (5) The catheter according to any one of (1) to (4), wherein the spring member substantially matches a lumen axis of the sheath portion with an axis of the insertion member.

  (6) The catheter according to (5), wherein the lumen of the sheath, the shafts of the insertion member, and the spring member substantially coincide with each other.

(7) The insertion member has a proximal end portion to which a liquid composition is supplied, and a lumen that extends from the proximal end portion to the distal end portion and communicates with the injection needle.
The base end portion of the sheath portion is connected to a hand operation portion having operation buttons arranged on the sides,
When the operation button is pressed, the hand operation unit performs an operation for projecting the injection needle from the distal end portion of the sheath portion, and punctures a target site with the projecting injection needle, and the insertion member The operation for injecting the liquid composition supplied from the base end of the tube into the target site and the operation for retracting the injection needle into the lumen of the distal end of the sheath are performed as a series of operations. The catheter according to any one of (1) to (6) above, which can be repeatedly obtained.

  According to the present invention configured as described above, since the spring member is disposed so as to surround the outer periphery of the insertion member, when the sheath portion is curved, the axial displacement of the insertion member is suppressed, and the base of the insertion member is suppressed. The relationship between the movement amount of the end portion and the movement amount of the distal end portion of the insertion member is favorably maintained. Since the injection needle is disposed at the distal end portion of the insertion member, it is possible to control the needle stick amount with high accuracy by adjusting the movement amount of the proximal end portion of the insertion member. On the other hand, since the spring member has a reduced diameter portion having a small outer diameter, a decrease in flexibility of the sheath portion is suppressed and the operability of the catheter is not deteriorated. Therefore, the catheter which has the favorable controllability with respect to the amount of needle sticks can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 is a side view of a main part of a catheter according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the main part of the catheter of FIG. 1, and FIG. 3 is a cross section showing a state in which the injection needle of the catheter protrudes 4 and 4 are cross-sectional views showing a state where the injection needle of the catheter is retracted.

  The catheter 100 includes a sheath portion 170, an insertion member 180, an injection needle 190, a different diameter spring member 110, and a hand operation portion 120.

  The sheath 170 is formed of a hollow tube and includes a distal end 172, a proximal end 175 connected to the hand operation unit 120, and a lumen 171 extending from the proximal end 175 toward the distal end 172. . An insertion member 180 is slidably disposed in the lumen 171.

  The shape of the sheath 170 is not particularly limited, but is preferably a cylindrical shape. The outer diameter of the sheath 170 is not particularly limited. For example, in an application for approaching cardiac tissue from the ventricle intravascularly, it is preferably 10 French (3.3 mm) or less. For example, in an application approaching cardiac tissue from the outside under an endoscope, it is preferably 15 mm or less.

  The material of the sheath 170 is not particularly limited, but polyolefin, olefin elastomer, polyester, soft polyvinyl chloride, polyurethane, urethane elastomer, polyamide, amide elastomer, polytetrafluoroethylene, fluororesin elastomer, polyimide, ethylene- Polymer materials such as vinyl acetate copolymer and silicon rubber can be used.

  The polyolefin is, for example, polypropylene or polyethylene. The olefin elastomer is, for example, a polyethylene elastomer or a polypropylene elastomer. The amide elastomer is, for example, a polyamide elastomer.

  When the sheath 170 is formed of a polymer material, for example, it is possible to improve the rigidity by using a superelastic alloy pipe, a buried coil or a buried mesh made of metal, and the like.

  The insertion member 180 is formed of a hollow tube, and includes a distal end portion 182 where the injection needle 190 is disposed, a proximal end portion which is disposed inside the hand operation unit 120 and to which the liquid composition is supplied, and a distal end from the proximal end portion. It has a lumen 181 that extends to the part 182 and communicates with the injection needle 190. The liquid composition is, for example, a therapeutic composition containing nucleic acid, protein, or cells.

  The shape of the insertion member 180 is not particularly limited, but is preferably cylindrical. The material of the insertion member 180 is not particularly limited, and examples thereof include metals, relatively high-rigidity polymer materials, and combinations of these appropriately. For example, the metal is stainless steel, Ni—Ti alloy, Cu—Zn alloy, cobalt alloy, or tantalum. For example, the polymer material is polyamide, polyimide, ultrahigh molecular weight polyethylene, polypropylene, or fluororesin.

  The outer diameter of the insertion member 180 is not particularly limited as long as it can slide inside the lumen 171 of the sheath 170, but is preferably 0.3 to 1.0 mm. The inner diameter of the insertion member 180 is not particularly limited, but is preferably 0.2 to 0.9 mm.

  The injection needle 190 is, for example, a hollow needle having a diameter of 0.1 to 1.0 mm, and the liquid composition is supplied from the hand operation unit 120 via the lumen 181 of the insertion member 180. The distal end portion 182 of the insertion member 180 is configured to protrude from the distal end portion 172 of the sheath portion 170. Therefore, the injection needle 190 can inject the liquid composition into the target site 10 by protruding from the distal end 172 of the sheath 170 corresponding to the protruding operation of the insertion member 180.

  The target site 10 is a lesion site in a diseased tissue in a living body, such as a heart tissue. When the target site 10 is a peripheral site of the myocardial infarction, the liquid composition is, for example, a drug solution that can be expected to recover cardiac function.

  The injection needle 190 is configured by a beveled blade surface formed by applying a needle attachment process to the distal end portion 182 of the insertion member 180. However, the injection needle 190 is not limited to a form formed integrally with the insertion member 180. For example, a separate injection needle 190 can be attached (joined) to the distal end portion 182 of the insertion member 180. .

  The different diameter spring member 110 is disposed in a gap formed between the lumen 171 of the sheath portion 170 and the outer periphery of the insertion member 180 so as to surround the outer periphery of the insertion member 180. Therefore, when the sheath portion 170 is curved, the different diameter spring member 110 suppresses the axial displacement of the insertion member 180, and the amount of movement of the proximal end portion of the insertion member 180 and the amount of movement of the distal end portion 182 of the insertion member 180 Maintain a good relationship. Since the injection needle 190 is disposed at the distal end portion 182 of the insertion member 180, the amount of needle sticking can be controlled with high accuracy by adjusting the movement amount of the proximal end portion of the insertion member 180.

  Since the gap has an annular cross section, the different-diameter spring member 110 has a spiral shape. The helical shape is preferable because it is easy to manufacture. However, for example, it is also possible to form the different diameter spring members 110 by sequentially connecting the annular members at a predetermined interval and disposing them in the gap. The cross-sectional shape of the different-diameter spring member 110 is preferably circular in order to follow the deformation of the sheath portion 170 and the insertion member 180 satisfactorily.

  The axes of the lumen 171 of the sheath 170, the insertion member 180, and the different diameter spring member 110 are substantially coincident. In this case, the different diameter spring member 110 can easily make the axis of the lumen 171 of the sheath portion 170 substantially coincide with the axis of the insertion member 180, and can improve the effect of suppressing the axial deviation of the insertion member 180. It is.

  The different-diameter spring member 110 has two types of parts (expanded part and reduced-diameter part) 111 and 112 having different outer diameters. A plurality of enlarged diameter portions 111 and reduced diameter portions 112 are alternately arranged. Since the different diameter spring member 110 has the reduced diameter portion 112 having a small outer diameter, a decrease in flexibility of the sheath portion 170 is suppressed, and the operability of the catheter 100 is not decreased. The wire diameter of the different diameter spring member 110 is preferably thin from the viewpoint of flexibility.

  The outer diameter of the enlarged diameter portion 111 substantially matches the inner diameter of the lumen 171 of the sheath portion 170, and the inner diameter of the reduced diameter portion 112 substantially matches the outer diameter of the insertion member 180. Therefore, it is possible to improve the effect of suppressing the axial deviation of the insertion member 180.

  The distal end portion and the proximal end portion of the different diameter spring member 110 are fixed to the distal end side and the proximal end portion side of the lumen 171 of the sheath portion 170, respectively. The fixing method is not particularly limited, but for example, adhesion or caulking can be applied.

  The material of the different-diameter spring member 110 is not particularly limited as long as it has appropriate elasticity, and a metal or a polymer material can be applied. However, the different diameter spring member 110 is in contact with a body fluid such as blood, and the insertion member 180 slides on the inner periphery of the reduced diameter portion 112. Therefore, it is preferable to form the different diameter spring member 110 from a material having corrosion resistance and low friction, for example, a stainless steel or a Ni—Ti alloy. It is also possible to form a coating layer having good slidability on the inner periphery of the reduced diameter portion 112.

  Further, the enlarged diameter portion 111 and the reduced diameter portion 112 are manufactured separately from different materials and / or wire diameters, and the enlarged diameter portion 111 and the reduced diameter portion 112 are sequentially joined to form the different diameter spring member 110. Is also possible.

  FIG. 5 is a chart for explaining measurement results regarding controllability of the needle stick amount of the catheter.

  The controllability of the needle puncture amount of the catheter is such that the length of the distal end portion 182 of the insertion member 180 protruding from the sheath portion 170 is moved by moving the proximal end portion of the insertion member 180 in a state where one portion of the sheath portion 170 is bent at a right angle. Was evaluated by measuring with calipers. Five kinds of movement amounts of 1 mm, 2 mm, 3 mm, 5 mm, and 10 mm were applied to the movement amount of the base end portion of the insertion member 180.

  The total length of the sheath portion 170 is 1600 mm, and the length from the end surface of the distal end portion 172 to the curved portion is 60 mm. The inner diameter of the sheath 170 is 1.8 mm. The insertion member 180 is made of a Ni—Ti alloy, has an outer diameter of 0.37 mm, and an inner diameter of 0.27 mm.

  The different diameter spring member 110 according to the embodiment has an enlarged diameter portion 111 having an outer diameter of 1.7 mm and an inner diameter of 1.5 mm, and a reduced diameter portion 112 having an outer diameter of 0.7 mm and an inner diameter of 0.5 mm. The total length of the different diameter spring member 110 is 1500 mm. The length of the enlarged diameter portion 111 and the reduced diameter portion 112 is 5 mm each, and the number of repetitions is 150. The material of the different diameter spring member 110 is a stainless steel rope.

  Comparative Example 1 is a case where no spring member is provided. The comparative example 2 is created by disposing a small diameter spring member corresponding to the reduced diameter portion 112 in the gap. Comparative Example 3 is created by disposing a large-diameter spring member corresponding to the enlarged-diameter portion 111 in the gap.

  As shown in FIG. 5, the relationship between the amount of movement of the proximal end portion of the insertion member 180 and the length (projection amount) of the distal end portion 182 of the insertion member 180 protruding from the sheath portion 170 is the first to third comparative examples. Compared to the above, the example is better, and the axial displacement of the insertion member 180 is suppressed.

  In particular, in the case of 1 mm in which the movement amount of the base end portion of the insertion member 180 is minute, in Comparative Examples 1 to 3, the protrusion of the insertion member 180 from the sheath portion 170 was not measured. A protrusion of 0.8 to 0.9 mm was measured. Further, the difference between the movement amount of the proximal end portion of the insertion member 180 and the protrusion amount is 1 to 3 mm in Comparative Examples 1 to 3, and 0 to 0.4 mm in the example.

  For example, the thickness of the myocardial infarction lesion is about 3 to 4 mm and is thin, and therefore, the needle stick amount is required to be controlled with high accuracy of 1 mm or less. However, unlike the cases of Comparative Examples 1 to 3, the present embodiment can be applied as shown by the results of the examples.

  As described above, the embodiment suppresses the axial displacement of the insertion member, can maintain the relationship between the movement amount of the proximal end portion of the insertion member and the protrusion amount, and the proximal end of the insertion member. It was confirmed that the needle stick amount can be controlled with high accuracy by adjusting the movement amount of the part.

  FIG. 6 is a schematic external view for explaining an example of a hand operation unit included in the catheter according to the embodiment of the present invention.

  The hand operation unit 120 includes a nozzle unit 121, an operation button 140, a lock tab 148, an operation tab 160, and a lid 128. The nozzle portion 121 is removably attached with a cap 130 to which the base end portion 175 of the sheath portion 170 is attached, and a protrusion amount adjusting mechanism for adjusting the protrusion amount of the injection needle 190 is provided inside. .

  As the material of the parts constituting the hand operation unit 120, for example, polycarbonate, polypropylene, polyethylene, polystyrene, urethane, ABS resin, MBS resin, PMMA resin, stainless steel, aluminum, and titanium can be used. In addition, as a method for molding the parts constituting the hand operation unit 120, for example, injection molding, cutting, or pressing can be applied.

  The operation button 140 is disposed on the side of the hand operation unit 120, and includes an injection needle driving mechanism for projecting and retracting the injection needle 190 and a liquid composition injection mechanism for injecting a predetermined amount of the liquid composition. Used to operate. The lock tab 148 can lock the operation button 140 and prevent an erroneous operation. The operation tab 160 is used to control an injection amount adjusting mechanism for adjusting the injection amount of the liquid composition.

  The lid 128 is connected to the main body case 122 so as to be openable and closable, and is used to house a syringe 195 that contains the liquid composition therein. The syringe 195 is a disposable type and is detachably incorporated in the hand operation unit 120. Therefore, the replacement of the liquid composition is easy, and the risk of infection can be reduced as compared with the case of reusing the container containing the liquid composition. The opening / closing mechanism and the locking mechanism of the lid 128 are not particularly limited, and other appropriate methods can be employed as necessary.

  FIG. 7 is a cross-sectional view for explaining the protruding amount adjustment mechanism of the injection needle, and shows the distal end portion of the hand operating portion.

  The cap 130 has a distal end 131 in which a cylindrical recess 132 is formed and a proximal end 135 in which an enlarged diameter portion 136 is formed. The concave portion 132 has an inner peripheral surface to which a distal end outer peripheral surface of the base end portion 175 of the sheath portion 170 is fixed, and a bottom surface on which an opening 133 in which the base end portion 185 of the insertion member 180 extends slidably is formed. And have. The enlarged diameter portion 136 has an outer peripheral surface on which a thread groove 137 is formed.

  The nozzle portion 121 has a cylindrical shape, and has a tip where an opening 123 into which the tip 131 of the cap 130 is slidably inserted is formed, and a screw groove 124 corresponding to the screw groove 137 of the cap 130 is formed. And a peripheral surface. The tip has a reduced diameter, and the inner diameter of the opening 123 is smaller than the outer diameter of the enlarged diameter portion 136 of the cap 130. Therefore, the tip functions as a stopper that prevents the cap 130 from falling off.

  When the cap 130 is rotated, the screw groove 137 of the cap 130 and the screw groove 124 of the nozzle portion 121 are fitted to each other, and the cap 130 moves in the direction away from the nozzle portion 121 or approaches in a direction close to the nozzle portion 121 according to the rotation direction. Moving. The sheath part 170 is fixed to the cap 130, while the insertion member 180 is not restrained by the cap 130, so that the relative position between the insertion member 180 and the sheath part 170 changes.

Therefore, by rotating the cap 130 and changing the relative position between the insertion member 180 and the sheath portion 170, it is possible to adjust the protruding amount of the injection needle 190 disposed at the distal end portion 182 of the insertion member 180. . The length L ₁ of the thread groove 124 is formed, an adjustable range of the protrusion amount.

  Further, the different diameter spring member 110 is disposed between the lumen 171 of the sheath portion 170 and the outer periphery of the insertion member 180, and the axial displacement of the insertion member 180 is suppressed, and the proximal end portion 185 of the insertion member 180 is The relationship between the amount of movement and the amount of protrusion of the injection needle 190 is maintained well. Therefore, even when the sheath 170 is partially bent at a right angle, the injection needle 190 protrudes in accordance with the set protrusion amount, so that the needle stick amount is controlled with high accuracy.

  As described above, the protruding amount adjustment mechanism of the injection needle 190 according to the present embodiment is based on the change in the relative position between the insertion member 180 and the sheath portion 170 caused by the fitting of the screw grooves 124 and 137.

  FIG. 8 is a cross-sectional view for explaining the injection needle driving mechanism in the hand operation unit 120, showing the vicinity of the operation button 140 in the hand operation unit 120. FIG. 9 shows the lock of the operation button 140. It is a top view for demonstrating a mechanism.

  The operation button 140 has an extended portion inside the main body case 122, and the extended portion has a slot 141, a guide groove 143, a pressing member 144, a rack 145, and a concave portion 147, and in the vicinity thereof. The lock tab 148, the transmission member 150, and the needle drive member 155 are arranged.

  The slot 141 has an oval shape, and a guide pin 142 fixed to the main body case 122 is slidably inserted. Therefore, when the operation button 140 is pressed, the inner periphery of the slot 141 slides on the outer periphery of the guide pin 142, so that the operation button 140 moves toward the inside of the main body case 122.

  The guide groove 143 is used to link the operation button 140 and the transmission member 150 and has a semi-oval shape. The pressing member 144 has elasticity, can be bent, and has a triangular tip portion 144A. The rack 145 includes a protruding portion 145A and a plurality of sawtooth portions 145B. The distal end portion 144A and the protruding portion 145A are disposed close to each other.

  The operation button 140 activates the injection needle drive mechanism simultaneously with the movement, and the transmission member 150 of the injection needle drive mechanism turns to move the needle drive member 155 toward the cap 130 (see FIG. 8). Since the insertion member 180 is fixed to the needle driving member 155, the injection needle 190 disposed at the distal end portion 182 of the insertion member 180 is moved from the distal end portion 172 of the sheath portion 170 according to the setting of the protrusion amount adjustment mechanism. Protruding.

  The distal end portion 144A, the protruding portion 145A, and the sawtooth portion 145B are used for interlocking the operation button 140 and the liquid composition injection mechanism. Note that a spring (elastic body) 146 is disposed inside the operation button 140 and urges the operation button 140 outward.

  As shown in FIG. 9, the lock tab 148 is movably disposed in the opening 125 formed in the main body case 122. The opening 125 is rectangular. The lock tab 148 has a rectangular base 149 disposed inside the main body case 122. The base 149 has a shape larger than the opening 125 and has a protrusion 149A.

  The recess 147 of the operation button 140 is aligned with the protrusion 149A and has a corresponding shape. Therefore, when the lock tab 148 is moved toward the recess 147, the protrusion 149A and the recess 147 are fitted to lock the operation button 140. On the other hand, when the lock tab 148 is moved away from the recess 147, the fitting between the projection 149A and the recess 147 is released, and the operation button 140 becomes movable.

  As described above, the hand operation unit 120 has the lock mechanism of the operation button 140, and by appropriately locking the movement of the operation button 140, it is possible to prevent an erroneous operation.

  The transmission member 150 has a triangular shape, is supported so as to be pivotable about an axis 151, and has through holes into which the connecting pins 152 and 153 are inserted. The connection pin 152 is slidably connected to the guide groove 143 of the operation button 140.

  Therefore, when the operation button 140 moves toward the inside of the main body case 122, the guide groove 143 presses the connection pin 152, so that the transmission member 150 turns around the shaft 151. At this time, the connecting pin 152 moves along the guide groove 143. The connecting pin 153 is used for interlocking the transmission member 150 and the needle driving member 155.

  The needle drive member 155 has a proximal end portion 185 of the insertion member 180 fixed thereto. The end portion of the base end portion 185 is connected by relaxing a flexible hollow tube 192. The tube 192 extends from a plug 193 detachably connected to the nozzle 194 of the syringe 195, and the liquid composition accommodated in the syringe 195 circulates inside. As a material of the tube 192 and the plug 193, for example, vinyl chloride, soft polypropylene, silicon, polyurethane, styrene elastomer, and the like are preferable.

  The needle drive member 155 has an L-order shape and has oval slots 156 and 157 arranged in the intersecting direction. The slot 156 is connected to the connecting pin 153 of the transmission member 150. In the slot 157, a guide pin 158 fixed to the main body case 122 is slidably inserted.

  Therefore, when the transmission member 150 rotates, the outer periphery of the connecting pin 153 presses the inner periphery of the slot 156, so that the inner periphery of the slot 157 slides on the outer periphery of the guide pin 158, and the needle driving member 155 has the cap 130. Move towards. At this time, the outer periphery of the connecting pin 153 slides on the inner periphery of the slot 156 and moves. Since the proximal end portion 185 of the insertion member 180 is fixed to the needle driving member 155, the injection needle 190 disposed at the distal end portion 182 of the insertion member 180 protrudes from the distal end portion 172 of the sheath portion 170.

  As described above, when the operation button 140 is pushed toward the inside of the main body case 122, the transmission member 150 is turned, while the transmission member 150 moves the needle driving member 155 toward the cap 130. That is, the injection needle drive mechanism according to the present embodiment causes the needle drive member 155, the insertion member 180, and the injection needle 190 to perform the downward movement caused by the pressing operation of the operation button 140 via the turning operation of the transmission member 150. Based on converting into forward movement.

  10 and 11 are cross-sectional views of the intermediate portion and the rear end of the hand operation unit 120, and FIGS. 12 and 13 are plan views of the ratchet member and the transmission member of the liquid composition injection mechanism in the hand operation unit 120. FIG. 14 is an enlarged view of a main part for explaining the liquid composition injection mechanism, showing a non-operation state, and FIG. 15 is an enlarged view of a main part for explaining the operation start state following FIG. FIG. 16 is an enlarged view of a main part for explaining the operation completion state following FIG. 15.

  In the vicinity of the operation button 140, a ratchet member 162, a transmission member 163, a syringe drive member 166, a syringe table 199, and an operation tab 160 are arranged.

  The ratchet member 162 is supported so as to be pivotable about a shaft 162A, a connector 162B to which a spring (elastic member) 165A is connected, a protrusion 162C that can be fitted to the sawtooth portion 145B of the rack 145, and the rack 145 It has a protrusion 162D that can come into contact with the protrusion 145A. The spring 165 </ b> A is fixed to the main body case 122 and biases the ratchet member 162.

  The transmission member 163 is supported so as to be pivotable about a shaft 163A, and includes a connector to which a spring (elastic member) 165B is connected, and a protrusion 163B and an extension portion 163C used to move the syringe drive member 166. . The spring 165B is fixed to the main body case 122 and biases the transmission member 163. The expanded portion 163C can come into contact with the distal end portion 144A of the pressing member 144 of the operation button 140.

  The syringe drive member 166 has a d-shape having a rectangular portion and a long arm extending from the rectangular portion. The rectangular portion is formed with an opening 166A in which the protrusion 163B is disposed. The arm has a tip provided with a claw 167.

  Therefore, when the operation button 140 is pushed toward the inside of the main body case 122, the liquid composition injection mechanism shifts from the non-operation state to the operation completion state via the operation start state.

  In the initial state shown in FIG. 14, that is, the non-operating state, the protrusion 162C of the ratchet member 162 abuts on the end of the rack 145 where the sawtooth portion 145B is not formed based on the biasing force of the springs 165A and 165B. The protrusion 163B of the transmission member 163 holds the syringe drive member 166 at the initial position via the opening 166A in which the protrusion 163B is disposed.

  In the half-pressed state shown in FIG. 15, that is, in the operation start state, the pressing member 144 and the rack 145 of the operation button 140 move toward the inside. The protrusion 162C of the ratchet member 162 slides on a flat portion where the sawtooth portion 145B is not formed, and fits with the sawtooth portion 145B of the rack 145. Since the ratchet member 162 is movable around the shaft 162A, the protrusion 162C is sequentially fitted with the adjacent sawtooth portion 145B as the rack 145 moves. In addition, the said flat part is set corresponding to the operation time of an injection needle drive mechanism. That is, the length of the flat portion is set so that the liquid composition injection mechanism is activated after the injection operation of the injection needle 190 by the injection needle drive mechanism is completed.

  The fitting between the projection 162C and the sawtooth portion 145B fixes the rack 145, prevents the operation button 140 from retreating or returning to the initial position, and prevents malfunction. Further, since the fitting between the projection 162C and the sawtooth portion 145B causes a click feeling, the pressing state of the operation button 140 can be grasped.

  On the other hand, the extended portion 163C of the transmission member 163 contacts the distal end portion 144A of the pressing member 144. Since the transmission member 163 can move around the shaft 163A, the transmission member 163 gradually turns by pressing the expansion portion 163C as the distal end portion 144A moves. The protrusion 163B of the transmission member 163 presses the inner periphery of the opening 166A of the syringe drive member 166, and moves the syringe drive member 166 toward the rear end side of the main body case 122.

  In the fully-pressed state shown in FIG. 16, that is, the operation completion state, the pressing member 144 and the rack 145 of the operation button 140 reach the most advanced position. At this time, the ratchet member 162 is separated from the sawtooth portion 145B of the rack 145, and the transmission member 163 is at the maximum turning position, and the driving of the syringe driving member 166 is finished.

  Therefore, when the pressing of the operation button 140 is removed, the operation button 140 returns to the initial state based on the biasing force of the spring 146. On the other hand, the ratchet member 162 returns to the initial state based on the contact between the protrusion 162D and the protrusion 145A of the rack 145 and the biasing force of the spring 165A. The transmission member 163 returns to the initial state based on the biasing force of the spring 165B. At this time, the protrusion 163B of the transmission member 163 presses the inner periphery of the opening 166A of the syringe drive member 166, and brings the syringe drive member 166 to the initial position.

  The syringe base 199 has a recess 199A, an enlarged diameter portion 199B, and a rack 168. Recess 199A has an arcuate cross section, and the outer cylinder of syringe 195 is detachably disposed. The enlarged diameter portion 199B is urged toward the operation button by a spring (elastic body) 169, and its inner diameter is smaller than the outer diameter of the flange 196 of the outer cylinder. The rack 168 has a plurality of right-angled triangular teeth 168 </ b> A, is disposed on the side facing the syringe drive member 166, and can be engaged with the claw 167 of the syringe drive member 166.

  Therefore, when the rack 168 and the claw 167 are engaged, the movement of the syringe driving member 166 causes the movement of the syringe base 199 toward the rear end side of the main body case 122. As a result, the enlarged diameter portion 199B of the syringe base 199 comes into contact with the flange 196 of the outer cylinder and accompanies the outer cylinder of the syringe 195. Note that it is preferable to insert a support bar inside the spring 169 to suppress unnecessary deformation of the spring 169.

  A pusher (plunger) 197 is slidably inserted into the outer cylinder, and a base 198 of the pusher 197 is fixed. Therefore, the tip 197 </ b> A of the pusher 197 moves inside the outer cylinder toward the nozzle 194, and pushes out the liquid composition accommodated inside the outer cylinder of the syringe 195. That is, in order to inject the liquid composition, it is not necessary to press and move the base 198 of the pusher 197. Therefore, it is not necessary to arrange an operation space behind the base portion 198 of the pusher 197, the rear end portion of the main body case 122 becomes compact, and the overall length of the hand operation portion 120 can be shortened.

  As described above, when the operation button 140 is pushed toward the inside of the main body case 122, the ratchet member 162 and the transmission member 163 are driven after the completion of the protruding operation of the injection needle 190 by the injection needle drive mechanism, and the syringe drive member 166 is moved toward the rear end side of the hand operation unit 120. Since the syringe drive member 166 accompanies the outer cylinder of the syringe 195, the pusher 197 moves inside the outer cylinder of the syringe 195 toward the nozzle 194.

  That is, in the liquid composition injection mechanism according to the present embodiment, the downward movement caused by the pressing operation of the operation button 140 is performed on the outer cylinders of the syringe driving member 166, the syringe base 199, and the syringe 195 via the ratchet mechanism. This is based on the fact that the position of the pusher 197 inside the outer cylinder is relatively changed by converting into forward movement.

  FIG. 17 is an enlarged view of a main part for explaining a restraining mechanism of the syringe base 199 in the hand operation unit 120.

  The lid 128 of the main body case 122 is formed with hooks 127 and 129 having elasticity. The hook 127 fixes the lid 128 to the main body case 122 by engaging with a recess 127 </ b> A formed in the main body case 122. When the rack 168 moves toward the rear end portion, the hook 129 slides along the slope of the tooth 168A, and thus does not hinder the movement. On the other hand, when the rack 168 moves in the opposite direction, the hook 129 contacts the vertical surface of the teeth 168A and stops the rack 168.

  Therefore, the hook 129 functions as a stopper for preventing the syringe table 199 on which the rack 168 is formed from returning backward. When the hook 127 and the recess 127A are manually disengaged and the lid 128 is opened, the hook 129 formed on the lid 128 is separated from the rack 168, and the engagement between the hook 129 and the rack 168 is released. Is done. Since the syringe table 199 is biased toward the operation button by the spring 169, the syringe table 199 returns backward and returns to the initial position.

  FIG. 18 is an enlarged view of a main part for explaining the liquid composition injection amount adjusting mechanism in the hand operation unit 120, and shows an initial state when the maximum injection amount is set. FIG. FIG. 20 is a main part enlarged view showing an initial state when an injection amount smaller than the maximum injection amount according to FIG. 18 is set. FIGS. 21 and 21 are enlarged views of the main part showing the final state when the small injection amount according to FIG. 20 is set.

  The operation tab 160 is L-shaped and includes a protrusion 160 </ b> A exposed to the outside and a plate 161 that extends inside the main body case 122. The protrusion 160 </ b> A is movably disposed in the opening 126 formed in the main body case 122. The opening 126 has a rectangular shape. The plate 161 is disposed in parallel to the rack 168 of the syringe table 199 and abuts the rack 168 in a slidable manner. Therefore, the plate 161 obstructs the engagement between the claw 167 of the syringe drive member 166 and the rack 168.

  When the projection 160A is set so that the tip of the claw 167 in the initial position is positioned on the end surface of the plate 161 (see FIG. 18), the claw 167 is moved to the rack 168 at the same time as the syringe driving member 166 moves. Engage and drive the syringe base 199 (see FIG. 19). At this time, since the plate 161 does not interfere with the engagement between the claw 167 and the rack 168, the moving amount of the syringe driving member 166 and the moving amount of the syringe table 199 substantially coincide with each other, and the injection amount of the liquid composition is , Become the maximum.

On the other hand, the tip of the nail 167 in the initial position is, as will be positioned a distance L ₂ away from the end face of the plate 161, if the protrusion 160A is set (see FIG. 20), the syringe driving member 166 is moved, the pawl 167 slides the plate 161. The pawl 167, after distance _{L 2} moves, the rack 168 engages and drives the syringe mount 199 (see FIG. 21).

At this time, the movement amount of the syringe drive member 166 and the movement amount of the syringe table 199 do not coincide with each other, and the movement amount of the syringe table 199 is a value obtained by subtracting the distance L ₂ from the movement amount of the syringe drive member 166. . That is, the moving amount of the syringe driving member 166 is constant, by adjusting the set position of the projections 160A, by changing the distance L _2, the injection amount of the liquid composition is properly adjusted.

  As described above, the injection amount adjusting mechanism according to the present embodiment is based on obstructing the transmission that causes the movement of the syringe table 199 within an appropriate range.

  Next, an example of how to use the catheter 100 will be described. The target site is the peripheral site of the myocardial infarction, and the injected liquid composition is a drug solution that can be expected to recover cardiac function. Also, a stage at the end of endoscopic surgery in which a plurality of holes of about 10 mm are made between ribs, instruments such as an endoscopic camera and forceps are inserted into the holes, and treatment is performed while viewing the images of the endoscopic camera. 1 assumes a situation in which two holes for the endoscope camera and catheter 100 are used.

  First, the operator disengages the hook 127 of the lid 128 and the recess 127A of the main body case 122, and opens the lid 128. The hook 129 formed on the lid 128 is separated from the rack 168, and the engagement between the hook 129 and the rack 168 is released. Since the syringe table 199 is biased toward the operation button by the spring 169, the syringe table 199 returns backward and returns to the initial position (see FIG. 17).

  Then, the surgeon places the syringe 195 containing the liquid composition inside the main body case 122, and attaches the tube 192 connected to the insertion member 180 to the nozzle 194 of the syringe 195 (see FIG. 8).

  Thereafter, the surgeon rotates the cap 130 and changes the relative position between the insertion member 180 and the sheath portion 170, thereby adjusting the protruding amount of the injection needle 190 disposed at the distal end portion 182 of the insertion member 180 ( (See FIG. 7). Further, the injection amount of the liquid composition is adjusted by moving the protrusion 160A of the operation tab 160 and hindering the transmission that causes the movement of the syringe table 199 within an appropriate range (see FIGS. 18 to 21).

  When the setting of the protrusion amount adjustment mechanism and the injection amount adjustment mechanism is completed, the operator moves the lock tab 148 (see FIG. 9), and fits the protrusion 149A of the lock tab 148 and the recess 147 of the operation button 140 to operate. The button 140 is locked.

  Then, for example, the distal end portion 172 of the sheath portion 170 of the catheter 100 is inserted into the living body through a hole provided in advance between the scissors, and the target region (the peripheral region of the myocardial infarction portion is viewed while viewing the image of the endoscopic camera. ) And adhere closely to the tissue of the target site.

  The surgeon moves the lock tab 148, unlocks the operation button 140, presses the operation button 140 with the finger of one hand holding the hand operation unit 120, and places the operation button 140 inside the main body case 122. Push in.

  The operation button 140 activates the injection needle drive mechanism simultaneously with the movement, and the transmission member 150 of the injection needle drive mechanism turns to move the needle drive member 155 toward the cap 130 (see FIG. 8). Since the proximal end portion 185 of the insertion member 180 is fixed to the needle driving member 155, the injection needle 190 disposed at the distal end portion 182 of the insertion member 180 protrudes from the distal end portion 172 of the sheath portion 170.

  At this time, the different-diameter spring member 110 is disposed between the lumen 171 of the sheath portion 170 and the outer periphery of the insertion member 180, so that the axial displacement of the insertion member 180 is suppressed, and the proximal end portion 185 of the insertion member 180. The relationship between the amount of movement and the amount of protrusion of the injection needle 190 is well maintained. Therefore, even when the sheath 170 is partially bent at a right angle, the injection needle 190 protrudes in accordance with the setting of the protrusion amount adjustment mechanism, so that the needle stick amount is controlled with high accuracy.

  When the operation button 140 is further pushed toward the inside of the main body case 122, the liquid composition injection mechanism is actuated, the ratchet member 162 and the transmission member 163 are driven (see FIGS. 15 and 16), and the syringe drive member 166 moves toward the rear end side of the hand operation unit 120.

  Since the syringe drive member 166 accompanies the outer cylinder, the pusher 197 moves inside the outer cylinder toward the nozzle 194. As a result, the liquid composition accommodated in the syringe 195 is sent out and injected into the target site from the injection needle 190.

  When the operation button 140 reaches the most advanced position, the driving of the syringe driving member 166 is finished. Thereby, the supply of a predetermined amount of the liquid composition according to the setting of the injection amount adjusting mechanism is completed. When the surgeon stops (cancels) pressing of the operation button 140, the operation button 140, the injection needle drive mechanism, and the liquid composition injection mechanism return to the initial position based on the biasing force of the spring, and the injection needle 190 is retracted into the tip 172 of the sheath 170.

  Thereafter, the surgeon moves the distal end 172 of the sheath 170 toward the next target tissue and repeats the above operation to continuously apply a predetermined amount of the therapeutic composition to a plurality of locations in the heart tissue. Can be injected.

  As described above, this embodiment can provide a catheter having good controllability with respect to the amount of needle stick.

  Further, the hand operating part of the catheter has an operation for projecting the injection needle from the distal end portion of the sheath part, a puncture of the target site with the projected injection needle, and injection of the liquid composition into the target site An operation button that can continuously and continuously repeat the operation and the operation for retracting the injection needle to the lumen of the distal end portion of the sheath portion as a series of operations is provided. Accordingly, it is possible to inject the liquid composition over a wide range of target sites, and since it has good operability and is simple, it is preferable.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims.

  For example, when used under X-ray fluoroscopy, it is preferable to form the tip of the sheath using a resin containing a radiopaque material. In this case, the distal end portion of the sheath part has X-ray contrast properties and functions as an X-ray contrast marker. Therefore, it can be guided into the ventricle, for example, while confirming the position of the tip of the sheath under X-ray fluoroscopy. 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.

  Further, the present invention can be applied to gene therapy and cell therapy. Gene therapy is, for example, treatment for ischemic heart disease, and injecting a nucleic acid with a built-in injection needle is preferable because it is minimally invasive.

  Cell therapy is a treatment method for improving cardiac function by transplanting new cells (cardiomyocytes, skeletal myoblasts, smooth muscle cells, bone marrow-derived cells, peripheral blood stem cells, cord blood-derived cells) from the outside, for example. It is. Therefore, a built-in injection needle can be applied, for example, in order to transplant bone marrow-derived cells into an infarct.

It is a principal part side view of the catheter which concerns on embodiment of this invention. It is principal part sectional drawing of the catheter of FIG. It is sectional drawing which shows the state which the injection needle of the catheter protruded. It is sectional drawing which shows the state which the injection needle of the catheter retracted. It is a graph for demonstrating the measurement result regarding the controllability of the needle stick amount of a catheter. It is a schematic external view for demonstrating an example of the hand operation part which the catheter which concerns on embodiment of this invention has. It is sectional drawing for demonstrating the protrusion amount adjustment mechanism of an injection needle, and has shown the front-end | tip part of a hand operation part. It is sectional drawing for demonstrating the injection needle drive mechanism in a hand operation part, and has shown the vicinity centering on the operation button in a hand operation part. It is a top view for demonstrating the lock mechanism of an operation button. It is sectional drawing of the intermediate part of a hand operation part. It is sectional drawing of the rear-end part of a hand operation part. It is a top view of the ratchet member which the liquid composition injection | pouring mechanism in a hand operation part has. It is a top view of the transmission member which a liquid composition injection | pouring mechanism has. It is a principal part enlarged view for demonstrating a liquid composition injection | pouring mechanism, and has shown the non-operation state. It is a principal part enlarged view for demonstrating the operation start state following FIG. FIG. 16 is an enlarged view of a main part for explaining the operation completion state following FIG. 15. It is a principal part enlarged view for demonstrating the stop mechanism of the syringe stand in a hand operation part. It is a principal part enlarged view for demonstrating the injection amount adjustment mechanism of the liquid composition in a hand operation part, and has shown the initial state at the time of setting the maximum injection amount. It is a principal part enlarged view which shows the final state at the time of setting the maximum injection amount which concerns on FIG. It is a principal part enlarged view which shows the initial state when the injection amount smaller than the maximum injection amount which concerns on FIG. 18 is set. It is a principal part enlarged view which shows the final state at the time of setting the small injection amount which concerns on FIG.

Explanation of symbols

10. Target site,
100. Catheter,
110 .. Spring member with different diameter,
111 .. Diameter expansion part,
112 .. Reduced diameter part,
120..Hand control unit,
121 .. Nozzle part,
122 .. Body case,
123 .. opening,
124 .. groove,
125 .. opening,
126 .. opening,
127. Hook,
127A..Recess,
128 .. lid,
129. Hook,
130 .. Cap
131 ... tip
132 .. Recess,
133 .. opening,
135 .. Base end
136 .. Expanded part,
137..Groove,
140 .. Operation buttons
141 .. slot
142 .. Guide pin,
143 .. Guide groove,
144 ..Pressing member,
144A ... tip
145 ・ Rack,
145A ・ ・ Protruding part,
145B ・ ・ Sawtooth part,
146 .. Spring,
147 .. Recess,
148 .. Lock tab,
149 .. Base,
149A..Protrusions,
150 .. transmission member,
151 .. axis
152, 153 .. connecting pin,
155 .. Needle drive member,
156, 157 .. slot,
158 .. Guide pin,
160 .. Operation tab,
160A ・ ・ Protrusions,
161 .. plate,
162 .. Ratchet member,
162A ... axis
162B ... Connector
162C ・ ・ Protrusions,
162D..Protrusions,
163 .. Transmission member,
163A ... axis
163B ・ ・ Protrusions,
163C ・ ・ Expansion part,
165A, 165B ... Spring
166 .. Syringe drive member,
166A .. opening,
167 ... the nails,
168.Rack,
168A ... Teeth
169 .. Spring,
170 .. sheath part,
171, Lumen,
172..
175 .. Base end,
180 .. Insertion member,
181, Lumen,
182 ... tip
185 .. Base end,
190 .. Needle,
192 tube
193 .. plug,
194 Nozzle,
195 ・ ・ Syringe,
196 ・ ・ Flange,
197 ...
197A ... tip,
198 ・ ・ Base
199 ... Syringe stand
199A .. Recess,
199B ・ ・ Expanded part,
L ₁ .... length,
L ₂ ... Distance.

Claims (7)

A sheath having a lumen extending the interior;
An insertion member slidably disposed in the lumen of the sheath,
An injection needle that is disposed at the distal end of the insertion member and can protrude from the distal end of the sheath;
In a gap formed between the lumen of the sheath portion and the outer periphery of the insertion member, a spring member arranged so as to surround the outer periphery of the insertion member,
The catheter, wherein the spring member has an enlarged diameter part and a reduced diameter part having different outer diameters.   The catheter according to claim 1, wherein the spring member has a spiral shape.   The outer diameter of the enlarged diameter portion is substantially the same as the inner diameter of the lumen of the sheath portion, and the inner diameter of the reduced diameter portion is substantially the same as the outer diameter of the insertion member. The catheter according to claim 1 or 2.   The catheter according to any one of claims 1 to 3, wherein a plurality of the diameter-expanded portions and the diameter-reduced portions are alternately arranged.   The catheter according to any one of claims 1 to 4, wherein the spring member substantially matches a lumen axis of the sheath portion with an axis of the insertion member.   The catheter according to claim 5, wherein the lumen of the sheath, the insertion member, and the spring member have substantially the same axis. The insertion member has a proximal end portion to which a liquid composition is supplied, and a lumen extending from the proximal end portion to the distal end portion and communicating with the injection needle,
The base end portion of the sheath portion is connected to a hand operation portion having operation buttons arranged on the sides,
When the operation button is pressed, the hand operation unit performs an operation for projecting the injection needle from the distal end portion of the sheath portion, and punctures a target site with the projecting injection needle, and the insertion member The operation for injecting the liquid composition supplied from the base end of the tube into the target site and the operation for retracting the injection needle into the lumen of the distal end of the sheath are performed as a series of operations. The catheter according to any one of claims 1 to 6, wherein the catheter can be repeated.

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