JP7626634B2 - High frequency treatment tools - Google Patents

Description

The present invention relates to a high-frequency treatment device that is introduced into a living body via an endoscope.

In endoscopic surgery such as endoscopic sphincterotomy (EST), a treatment tool is used to perform treatment inside the body cavity through a treatment tool insertion channel of the endoscope that extends from the proximal side to the distal side. One such treatment tool is a papillotomy knife.

For example, in the treatment tools disclosed in Patent Documents 1 to 3, a conductive wire is inserted into a sheath (shaft) that extends from the tip to the proximal side, and a part of the conductive wire is exposed to the outside at the tip side of the treatment tool. By passing a high-frequency current through the conductive wire, tissue such as a lesion can be incised at the exposed part of the conductive wire.

JP 2004-73582 A JP 2016-54774 A JP 2001-79017 A

From the viewpoint of improving the efficiency of the procedure, it is beneficial to provide a treatment tool that allows the incision direction to be changed. Therefore, the present invention aims to provide a high-frequency treatment tool that allows the incision direction to be changed depending on the position of the conductive wire.

One embodiment of the high-frequency treatment tool of the present invention that has achieved the above object has a shaft and a conductive wire disposed within the shaft, the conductive wire has an exposed section that is at least partially exposed to the outside of the shaft, and the cross-sectional shape of the conductive wire taken along a cross section perpendicular to the longitudinal axis has a short axis and a long axis, and the direction of the long axis varies depending on the position of the exposed section. With the high-frequency treatment tool of the present invention, the user can change the incision direction depending on the position of the exposed section of the conductive wire that has the desired bending direction. This allows incisions to be made in multiple directions with a single high-frequency treatment tool, making it possible to treat a variety of lesions.

The conductive wire may have a first position within the exposed section and a second position proximal to the first position, and when the high-frequency treatment tool is viewed from the proximal side in the longitudinal axis direction of the shaft, the direction of the long axis of the cross-sectional shape at the first position may be tilted clockwise by 5 degrees or more than the direction of the long axis of the cross-sectional shape at the second position. The conductive wire may have a first position within the exposed section and a second position proximal to the first position, and when the high-frequency treatment tool is viewed from the proximal side in the longitudinal axis direction of the shaft, the direction of the long axis of the cross-sectional shape at the first position may be tilted counterclockwise by 5 degrees or more than the direction of the long axis of the cross-sectional shape at the second position.

The conductive wire may have a non-exposed section disposed in the first inner cavity of the shaft, and the direction of the long axis of the cross-sectional shape of the conductive wire may vary depending on the position of the non-exposed section. Also, the conductive wire may have a non-exposed section disposed in the first inner cavity of the shaft, and the direction of the long axis of the cross-sectional shape of the conductive wire may be the same at any position of the non-exposed section.

The conductive wire has an unexposed section disposed in a first lumen of the shaft, the unexposed section including a first unexposed section distal to the exposed section and a second unexposed section proximal to the exposed section, and the direction of the long axis of the cross-sectional shape of the conductive wire varies depending on the position in the first unexposed section, but may be the same at any position in the second unexposed section.

The conductive wire has a non-exposed section disposed in the first lumen of the shaft, the non-exposed section including a first non-exposed section distal to the exposed section and a second non-exposed section proximal to the exposed section, the shaft has a first opening and a second opening exposing the conductive wire, the second opening is disposed proximal to the first opening, and the distal end of the second non-exposed section of the conductive wire may be in contact with the first circumferential end side of the second opening of the inner wall of the shaft. The distal end of the second non-exposed section of the conductive wire may be in contact with the second circumferential end side of the second opening of the inner wall of the shaft. The proximal end of the first non-exposed section of the conductive wire may be in contact with the first circumferential end side of the first opening of the inner wall of the shaft.

In a cross section perpendicular to the longitudinal axis of the shaft in the exposed section of the conductive wire, the short axis of the conductive wire may be parallel to a straight line connecting the centroid of the shaft and the centroid of the conductive wire.

The conductive wire may have a non-exposed section disposed in a first lumen of the shaft, and the cross-sectional shape of a cross section perpendicular to the longitudinal axis of the conductive wire in the non-exposed section may be non-circular. The shaft may have a first lumen and a second lumen, and the tip of the conductive wire may be disposed in the first lumen. In this case, the high-frequency treatment device may further have a fixture disposed at the tip of the conductive wire and in contact with the inner wall of the first lumen.

The high-frequency treatment tool of the present invention allows the user to change the incision direction depending on the position of the exposed section of the conductive wire that has the desired bending direction. This allows incisions to be made in multiple directions with a single high-frequency treatment tool, making it possible to treat a variety of lesions.

1 is a side view of a high-frequency treatment device according to an embodiment of the present invention. 2 is an enlarged cross-sectional view (partial side view) of a distal end portion of the high-frequency treatment instrument shown in FIG. 1 . 3 is a cross-sectional end view of the shaft and conductive wire shown in FIG. 2 taken along line III-III. FIG. 4 is a cross-sectional end view of the conductive wire shown in FIG. 2 taken along line IV-IV. 3 is a cross-sectional end view of the conductive wire shown in FIG. 2 taken along line VV. 6 is a cut end view showing a modified example of the conductive wire shown in FIG. 5 . 3 is a cross-sectional end view of the conductive wire shown in FIG. 2 taken along line VII-VII. 3 is a cross-sectional end view of the conductive wire shown in FIG. 2 taken along line VIII-VIII. 3 is a cross-sectional end view of the conductive wire shown in FIG. 2 taken along line IX-IX. 3 is a cross-sectional end view of the conductive wire shown in FIG. 2 taken along line XX. 10 is a cut end view showing a modified example of the conductive wire shown in FIG. 9 . 2 is an enlarged plan view of a distal end portion of the high-frequency treatment instrument shown in FIG. 1 . 13 is a plan view showing a modified example of the high-frequency treatment device shown in FIG. 12.

The present invention will be described in more detail below based on the following embodiment, but the present invention is not limited to the following embodiment, and can of course be modified as appropriate within the scope of the above and below, all of which are included in the technical scope of the present invention. In addition, hatching and component symbols may be omitted in each drawing for convenience, but in such cases, reference should be made to the specification or other drawings. In addition, the dimensions of various components in the drawings may differ from the actual dimensions, as priority is given to contributing to an understanding of the features of the present invention.

One embodiment of the high-frequency treatment tool of the present invention has a shaft and a conductive wire disposed within the shaft, the conductive wire having at least a portion of an exposed section exposed to the outside of the shaft, and the cross-sectional shape of the conductive wire taken along a cross section perpendicular to the longitudinal axis has a short axis and a long axis, and the direction of the long axis varies depending on the position of the exposed section. With the high-frequency treatment tool of the present invention, the user can change the incision direction depending on the position of the exposed section of the conductive wire having the desired bending direction. This allows incisions to be made in multiple directions with a single high-frequency treatment tool, making it possible to treat a variety of lesions.

A high-frequency treatment tool is introduced into a body cavity via a treatment tool insertion channel of an endoscope and is used in a procedure such as EST. Hereinafter, the high-frequency treatment tool may be simply referred to as a treatment tool. An example of the configuration of a high-frequency treatment tool will be described with reference to Figs. 1 to 13. Fig. 1 is a side view of a high-frequency treatment tool according to one embodiment of the present invention. Fig. 2 is an enlarged cross-sectional view (partial side view) of the distal end of the high-frequency treatment tool shown in Fig. 1. Fig. 3 is a cut end view of the shaft and conductive wire shown in Fig. 2 taken along line III-III. Figs. 4 to 5 and Figs. 7 to 10 are cut end views of the conductive wire shown in Fig. 2, respectively. Figs. 6 and 11 are cut end views showing modified conductive wires. Fig. 12 is an enlarged plan view of the distal end of the high-frequency treatment tool shown in Fig. 1. Fig. 13 is a plan view showing a modified high-frequency treatment tool shown in Fig. 12. Note that the third opening 16 and the fifth opening are omitted in Figs. 12 to 13. The treatment tool 1 has a shaft 5 and a conductive wire 20.

In FIG. 1, the treatment tool 1 has an insertion section 2 that is inserted into the treatment tool insertion channel of the endoscope, and a handle 65 connected to the proximal side of the insertion section 2. A curved section 3 may be provided at the distal end of the insertion section 2 to facilitate insertion into a body cavity such as the nipple. The handle 65 may be capable of changing the degree of curvature of the distal section of the shaft 5 and the curved section 3. The configuration of the hand side for moving the treatment tool 1 will be described later.

The distal side of the treatment tool 1 refers to the distal end side of the shaft 5 in the longitudinal axis direction x, which is the side to be treated. The proximal side of the treatment tool 1 refers to the proximal end side of the shaft 5 in the longitudinal axis direction x, which is the side closest to the user. When each component is divided in half along its longitudinal axis, the proximal side is sometimes referred to as the proximal portion, and the distal side is sometimes referred to as the distal portion. The inside and outside of the shaft 2 refer to the inside and outside in the radial direction of the shaft 5, and the inside in the radial direction of the shaft 5 refers to the side closer to the center of the longitudinal axis of the shaft 5.

The shaft 5 is a long member having a longitudinal axis direction x, a radial direction, and a circumferential direction p. The shaft 5 has a distal end and a proximal end in the longitudinal axis direction x. Since the conductive wire 20 is disposed within the shaft 5, the shaft 5 preferably has a cylindrical structure. The shaft 5 preferably has one or more internal cavities, and the internal cavities preferably extend in the longitudinal axis direction x of the shaft 5.

In Figures 2 and 3, the shaft 5 has a first lumen 11 and a second lumen 12. The tip of the conductive wire 20 is disposed in the first lumen 11. The second lumen 12 can be used as a passage for a guidewire or a flow path for a liquid to be injected into the body cavity. Examples of liquids include physiological saline, hyaluronic acid solution, contrast agent, and liquids containing medicines or cells.

As shown in FIG. 3, the shaft 5 may have a third lumen 13. In this case, the second lumen 12 may be used as a passage for inserting a guidewire, and the third lumen 13 may be used as a flow path for liquid to be injected into the body cavity. The first lumen 11 may extend from the distal end to the proximal end of the shaft 5, and the distal end of the first lumen 11 may be located proximal to the distal end of the shaft 5.

The shaft 5 has one or more openings for exposing the conductive wire 20. The openings are connected to the inner cavity of the shaft 5. In Figs. 1 and 2, the shaft 5 has a first opening 14 and a second opening 15 in that order from the distal side on the outer peripheral surface of the distal portion, and the first inner cavity 11 is connected to the outside of the shaft 5 through the first opening 14 and the second opening 15. In this way, the conductive wire 20 may be exposed using multiple openings, but the conductive wire 20 may also be exposed from one opening. For example, the shaft 5 may have an opening extending in the longitudinal axis direction of the shaft 5 on the outer peripheral surface of the distal portion, and the conductive wire 20 may be exposed from the opening.

In FIG. 2, the shaft 5 has a tapered portion 8 at its distal end, the outer diameter of which decreases toward the distal end. The tapered portion 8 makes it easier for the treatment tool 1 to pass through the body. The tapered portion 8 is preferably located distal to the first opening 14.

The shaft 5 may have an opening for a purpose other than exposing the conductive wire 20. The shaft 5 may have at least one of a third opening 16 communicating with the first lumen 11, a fourth opening 17 communicating with the second lumen 12 and allowing the guide wire to protrude, and a fifth opening communicating with the third lumen 13 and releasing a fluid into the body cavity. At least one of the third opening 16, the fourth opening 17, and the fifth opening may be disposed in the tapered portion 8. At least one of the third opening 16, the fourth opening 17, and the fifth opening is preferably located distal to the first opening 14.

The shaft 5 is preferably flexible. This allows the shaft 5 to be deformed according to the shape of the body cavity. In order to maintain its shape, the shaft 5 is preferably elastic. The shaft 5 is preferably made of resin, metal, or a combination of resin and metal. Examples of the shaft 5 include a resin tube; a metal tube; a hollow body formed by arranging wires in a predetermined pattern; a hollow body having at least one of the inner and outer surfaces coated with resin; or a combination of these, for example, a combination of these connected in the longitudinal direction. The resin tube can be manufactured by, for example, extrusion molding. Examples of hollow bodies in which wires are arranged in a predetermined pattern include a cylindrical body having a mesh structure formed by simply crossing or weaving wires, and a coil in which wires are wound. The wires may be one or more solid wires, or one or more twisted wires. The cross-sectional shape of the wires may be, for example, a circle, an oval, a polygon, or a combination of these. The oval shape includes an ellipse, an egg, and a rounded rectangle, and the same applies in the following explanation. The type of mesh structure is not particularly limited, and the number of turns and density of the coil are also not particularly limited. The mesh structure and coil may be formed with a constant density over the entire longitudinal axis direction x of the shaft 5, or may be formed so that the density varies depending on the position in the longitudinal axis direction x of the shaft 5. In order to increase the flexibility of the metal tube, cuts or grooves may be formed on the outer surface of the metal tube. The shape of the cuts or grooves may be linear, arc-shaped, annular, spiral, or a combination of these. When the shaft 5 is a cylindrical resin tube, the shaft 5 may be composed of a single layer or multiple layers, and a part in the longitudinal axis direction x or circumferential direction p may be composed of a single layer, and the other part may be composed of multiple layers.

The cross-sectional shape of the shaft 5 perpendicular to the longitudinal axis direction x is not particularly limited, and can be, for example, a circle, an oval, a polygon, or a combination of these.

The conductive wire 20 is disposed in the shaft 5. By passing a high-frequency current through the conductive wire 20, the conductive wire 20 can be used as the knife portion of a high-frequency knife. This allows the conductive wire 20 to incise biological tissue and remove tissue such as diseased areas. The conductive wire 20 has a tip and a base end in the longitudinal direction. The conductive wire 20 extends as a whole from the distal side to the proximal side of the shaft 5. The tip of the conductive wire 20 is fixed to the shaft 5 so that the conductive wire 20 does not come off the shaft 5 during the procedure. A detailed method of fixing the tip of the conductive wire 20 to the shaft 5 will be described later. The base end of the conductive wire 20 is connected to a high-frequency power source so that electrical conductivity is ensured. The base end of the conductive wire 20 is also connected to the handle 65.

The conductive wire 20 has an exposed section 21, at least a portion of which is exposed to the outside of the shaft 5. The exposed section 21 is disposed between the tip and base ends of the conductive wire 20. In FIG. 2, the portion exposed from the first opening 14 and the second opening 15 of the shaft 5 is the exposed section 21. It is preferable that the exposed section 21 is a part of the tip of the conductive wire 20. By operating the handle 65 to advance and retreat the conductive wire 20, the length and degree of bending of the exposed section 21 can be changed, and the shape of the knife can be changed according to the procedure. The shape of the conductive wire 20 in the exposed section 21 is not particularly limited, but may be, for example, a loop shape or a half loop shape.

2, the conductive wire 20 has a non-exposed section 22 arranged in the first lumen 11 of the shaft 5. The non-exposed section 22 may include a first non-exposed section 221 located distal to the exposed section 21 and a second non-exposed section 222 located proximal to the exposed section 21. The exposed section 21 may be shorter than the non-exposed section 22. The conductive wire 20 may have an insulating layer on its surface to maintain electrical insulation. The insulating layer of the conductive wire 20 may be arranged not only in the non-exposed section 22 of the conductive wire 20 but also in a part of the exposed section 21 to prevent electrical current and incision to the endoscope or unintended tissue. The part of the exposed section 21 without the insulating layer functions as a knife section.

The shape of the cross section perpendicular to the longitudinal axis of the conductive wire 20 is not particularly limited, and can be a circle, an oval, a polygon, or a combination of these, but a non-circular shape is preferable. The cross section perpendicular to the longitudinal axis of the conductive wire 20 may be the same throughout the entire longitudinal axis of the conductive wire 20, or may differ depending on the position of the exposed section 21 or the unexposed section 22. The cross section may have only straight portions 25, may have only curved portions 26, or may have straight portions 25 and curved portions 26 as shown in FIG. 4.

The conductive wire 20 is preferably made of an elastically deformable material. The conductive wire 20 may be made of any conductive material, such as a superelastic alloy such as a Ni-Ti alloy, or stainless steel such as SUS303, SUS304, or SUS316. The conductive wire 20 may be made of a single member, or may be made by joining multiple members midway along the longitudinal axis. As a joining method, in addition to a method of crimping the ends of multiple members with a ring member such as a metal tube, welding, adhesives, etc. can be used. The conductive wire 20 may be a solid wire, or a twisted wire made by twisting together single wires.

As shown in Figures 4 and 5, the cross-sectional shape of the conductive wire 20 taken along a cross section perpendicular to the longitudinal axis has a short axis 23 and a long axis 24, and the direction of the long axis 24 of the cross-sectional shape varies depending on the position of the exposed section 21. With the treatment tool 1, the user can change the incision direction depending on the position of the conductive wire 20 in the exposed section 21 that has the desired bending direction. This allows incisions to be made in multiple directions with one treatment tool 1, making it possible to treat a variety of lesions.

In the present invention, the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 differs depending on the position of the exposed section 21 means that when the cross-sectional shapes are observed at two different positions in the longitudinal axis direction of the conductive wire 20, the directions of the long axis 24 of the two cross-sectional shapes are non-parallel. The description later that the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 differs depending on the position of the unexposed section 22 can also be interpreted in a similar manner.

The conductive wire 20 has a first position 41 and a second position 42 located closer to the first position 41 in the exposed section 21. The cross-sectional shape of the conductive wire 20 at the first position 41 is shown in FIG. 4, and the cross-sectional shape of the conductive wire 20 at the second position 42 is shown in FIG. 5. The first position 41 and the second position 42 can be set at any two positions in the exposed section 21. When the exposed section 21 of the conductive wire 20 is divided into two equal parts in the longitudinal direction of the shaft 5, the section on the distal side is the first exposed section 211, and the section on the proximal side is the second exposed section 212. In this case, the first position 41 may be located in the first exposed section 211, and the second position 42 may be located in the second exposed section 212. Also, the first position 41 and the second position 42 may be located in the first exposed section 211, and the first position 41 and the second position 42 may be located in the second exposed section 212.

The direction of the long axis 24 of the cross-sectional figure at the first position 41 may be different from the direction of the long axis 24 of the cross-sectional figure at the second position 42. The inclination angle of the direction of the long axis 24 of the cross-sectional figure at the first position 41 relative to the direction of the long axis 24 of the cross-sectional figure at the second position 42 is not particularly limited. For example, as shown in Figs. 4 and 5, when the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, it is preferable that the direction of the long axis 24 of the cross-sectional figure at the first position 41 is inclined clockwise by 5 degrees or more from the direction of the long axis 24 of the cross-sectional figure at the second position 42. By arranging the conductive wire 20 so that it is twisted clockwise when viewed from the proximal side, it becomes easier to perform the incision. Note that the direction of the long axis 24 in Fig. 4 is inclined clockwise by 40 degrees compared to Fig. 5.

When the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional figure at the first position 41 may be inclined clockwise by 10 degrees or more, 20 degrees or more, 180 degrees or less, 150 degrees or less, or 120 degrees or less than the direction of the long axis 24 of the cross-sectional figure at the second position 42.

Figure 6 shows a modified cross-sectional view at the second position 42. As shown in Figure 6, when the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, it is preferable that the direction of the long axis 24 of the cross-sectional view at the first position 41 is tilted counterclockwise by 5 degrees or more from the direction of the long axis 24 of the cross-sectional view at the second position 42. The incision direction can also be adjusted by arranging the conductive wire 20 so that it is twisted counterclockwise when viewed from the proximal side. Note that in Figure 4, the direction of the long axis 24 is tilted counterclockwise by 20 degrees compared to Figure 6.

When the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional figure at the first position 41 may be inclined counterclockwise by 10 degrees or more, 20 degrees or more, or may be inclined less than 180 degrees, 150 degrees or less, or 120 degrees or less than. In this specification, when the direction of the long axis 24 of the cross-sectional figure at the first position 41 is inclined more than 0 degrees and 180 degrees or less than the direction of the long axis 24 of the cross-sectional figure at the second position 42, it is expressed as clockwise, and when it is inclined more than 180 degrees and less than 360 degrees, it is expressed as counterclockwise. Therefore, a clockwise tilt of 181 degrees and a counterclockwise tilt of 179 degrees are synonymous, but in this case, it will be expressed as counterclockwise.

The conductive wire 20 may also be twisted within the first lumen 11. For example, as shown in Figures 2 and 7 to 10, the conductive wire 20 has a non-exposed section 22 arranged in the first lumen 11 of the shaft 5, and the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 may differ depending on the position of the non-exposed section 22. By twisting the conductive wire 20 in this way even in the non-exposed section 22, it becomes easier to adjust the bending direction of the conductive wire 20 so that incision can be made easily in the exposed section 21.

The non-exposed section 22 includes a first non-exposed section 221 that is distal to the exposed section 21, and a second non-exposed section 222 that is proximal to the exposed section 21. The conductive wire 20 has a third position 43 in the first non-exposed section 221 and a fourth position 44 that is proximal to the third position 43, and has a fifth position 45 in the second non-exposed section 222 and a sixth position 46 that is proximal to the fifth position 45. The cross-sectional diagram of the conductive wire 20 at the third position 43 is shown in FIG. 7, the cross-sectional diagram of the conductive wire 20 at the fourth position 44 is shown in FIG. 8, the cross-sectional diagram of the conductive wire 20 at the fifth position 45 is shown in FIG. 9, and the cross-sectional diagram of the conductive wire 20 at the sixth position 46 is shown in FIG. 10.

The third position 43 and the fourth position 44 can be set at any two positions within the first unexposed section 221. It is preferable that the third position 43 is located on the base end side of the tip of the conductive wire 20. Furthermore, when a fixing device 50 is disposed at the tip of the conductive wire 20, it is preferable that the third position 43 is located on the proximal side of the fixing device 50.

The fifth position 45 and the sixth position 46 can be set at any two positions within the second unexposed section 222. It is preferable that the sixth position 46 is located closer to the tip side than the base end of the conductive wire 20. It is also preferable that the sixth position 46 is located at the curved portion 3 of the shaft 5.

As shown in Figures 7 and 8, when the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional figure at the third position 43 may be inclined clockwise by 5 degrees or more, 10 degrees or more, 20 degrees or more, 90 degrees or less, 60 degrees or less, or 45 degrees or less than the direction of the long axis 24 of the cross-sectional figure at the fourth position 44. Note that in Figure 7, the direction of the long axis 24 is inclined 15 degrees clockwise compared to Figure 8.

When the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional figure at the third position 43 may be inclined counterclockwise by 5 degrees or more, 10 degrees or more, 20 degrees or more, 90 degrees or less, 60 degrees or less, or 45 degrees or less than the direction of the long axis 24 of the cross-sectional figure at the fourth position 44.

The direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 may be the same at any position in the first unexposed section 221. For example, when the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional shape at the third position 43 may be the same as the direction of the long axis 24 of the cross-sectional shape at the fourth position 44.

As shown in Figures 9 and 10, when the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional figure at the fifth position 45 may be inclined clockwise by 5 degrees or more, 10 degrees or more, 20 degrees or more, 90 degrees or less, 60 degrees or less, or 45 degrees or less than the direction of the long axis 24 of the cross-sectional figure at the sixth position 46. Note that in Figure 9, the direction of the long axis 24 is inclined 15 degrees clockwise compared to Figure 10.

When the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional figure at the fifth position 45 may be inclined counterclockwise by 5 degrees or more, 10 degrees or more, 20 degrees or more, 90 degrees or less, 60 degrees or less, or 45 degrees or less than the direction of the long axis 24 of the cross-sectional figure at the sixth position 46.

The direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 may be the same at any position in the second unexposed section 222. For example, when the treatment tool 1 is viewed from the proximal side of the longitudinal axis direction x of the shaft 5, the direction of the long axis 24 of the cross-sectional shape at the fifth position 45 may be the same as the direction of the long axis 24 of the cross-sectional shape at the sixth position 46.

The conductive wire 20 may be twisted in a portion of the non-exposed section 22, and may not be twisted in the remaining portion of the non-exposed section 22. FIG. 11 shows a modified cross-sectional view at the fifth position 45. The direction of the long axis 24 of the cross-sectional view of the conductive wire 20 may vary depending on the position in the first non-exposed section 221, and may be the same at any position in the second non-exposed section 222. For example, in FIGS. 7 to 8, the direction of the long axis 24 of the cross-sectional view at the third position 43 is inclined 15 degrees clockwise with respect to the direction of the long axis 24 of the cross-sectional view at the fourth position 44. As shown in FIGS. 10 and 11, the directions of the long axis 24 of the cross-sectional view of the conductive wire 20 at the fifth position 45 and the sixth position 46 extend in the vertical direction of the paper and are consistent. With this configuration, the bending direction of the conductive wire 20 can be adjusted so that the exposed section 21 can be easily incised.

The conductive wire 20 does not have to be twisted within the first lumen 11. The direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 may be the same at any position in the unexposed section 22. This configuration also allows the bending direction of the conductive wire 20 to be adjusted. In detail, the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 may be the same at any position in the first unexposed section 221 and at any position in the second unexposed section 222.

The direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the first exposed section 211 may be different from the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the first unexposed section 221. Also, the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the second exposed section 212 may be different from the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the second unexposed section 222.

The direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the first exposed section 211 may be the same as the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the first unexposed section 221. Also, the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the second exposed section 212 may be the same as the direction of the long axis 24 of the cross-sectional shape of the conductive wire 20 in the second unexposed section 222.

It is preferable that the conductive wire 20 is twisted at least in the exposed section 21 so that the conductive wire 20 contacts the inner wall 6 of the shaft 5 at the opening. For example, as shown in FIG. 12, the shaft 5 has a first opening 14 and a second opening 15 that expose the conductive wire 20, and the second opening 15 is arranged closer to the first opening 14. In the circumferential direction p of the shaft 5, the first opening 14 has a first end 141 and a second end 142, and the second opening 15 also has a first end 151 and a second end 152. In this case, it is preferable that the distal end of the second non-exposed section 222 of the conductive wire 20 contacts the first end 151 side of the second opening 15 of the inner wall 6 of the shaft 5 in the circumferential direction p. By arranging the conductive wire 20 in this manner, the bending direction of the conductive wire 20 can be adjusted so that the incision can be easily performed in the exposed section 21.

To adjust the bending direction of the conductive wire 20 in the exposed section 21, the length of the first opening 14 and the length of the second opening 15 may be different in the circumferential direction p of the shaft 5. Also, the first end 141 of the first opening 14 and the first end 151 of the second opening 15 may be in different positions in the circumferential direction p of the shaft 5. Similarly, the second end 142 of the first opening 14 and the second end 152 of the second opening 15 may be in different positions in the circumferential direction p of the shaft 5.

As shown in FIG. 12, the proximal end of the first unexposed section 221 of the conductive wire 20 may be in contact with the first end 141 side of the first opening 14 in the inner wall 6 of the shaft 5 in the circumferential direction p. By arranging the conductive wire 20 in this manner, the bending direction of the conductive wire 20 can be adjusted to make it easier to make an incision in the exposed section 21.

As shown in FIG. 13, it is preferable that the distal end of the second unexposed section 222 of the conductive wire 20 contacts the second end 152 side of the second opening 15 in the inner wall 6 of the shaft 5 in the circumferential direction p. By arranging the conductive wire 20 in this manner, the bending direction of the conductive wire 20 can also be adjusted.

When the shaft 5 does not have the second opening 15 and the conductive wire 20 is exposed only from the first opening 14, the distal end or proximal end of the non-exposed section 22 of the conductive wire 20 may be in contact with the inner wall 6 of the shaft 5 as follows. The distal end of the second non-exposed section 221 of the conductive wire 20 may be in contact with the first end 141 side of the first opening 14 of the inner wall 6 of the shaft 5 in the circumferential direction p. The distal end of the second non-exposed section 222 of the conductive wire 20 may be in contact with the second end 142 side of the first opening 14 of the inner wall 6 of the shaft 5 in the circumferential direction p. The proximal end of the first non-exposed section 221 of the conductive wire 20 may be in contact with the first end 141 side of the first opening 14 of the inner wall 6 of the shaft 5 in the circumferential direction p.

As shown in FIG. 3, in the exposed section 21 of the conductive wire 20, in a cross section perpendicular to the longitudinal axis direction x of the shaft 5, it is preferable that the short axis 23 of the conductive wire 20 is parallel to the straight line connecting the centroid 19 of the shaft 5 and the centroid 27 of the conductive wire 20. By using a conductive wire 20 having such a cross section, it is possible to position the conductive wire 20 in a direction away from the shaft 5. The centroid is the point at which the figure is balanced when the weight acts uniformly and the position is used as a fulcrum. The centroid coincides with the center of gravity when the cross section perpendicular to the longitudinal axis direction x is a uniform plate.

At the midpoint of the exposed section 21 of the conductive wire 20, in a cross section perpendicular to the longitudinal axis direction x of the shaft 5, it is preferable that the straight line connecting the centroid 19 of the shaft 5 and the centroid 27 of the conductive wire 20 is parallel to the short axis 23 of the conductive wire 20. The midpoint of the exposed section 21 means the midpoint in the longitudinal direction of the conductive wire 20 when the conductive wire 20 is exposed from the shaft 5 so that the exposed portion is at its longest. For example, if the length of the conductive wire 20 is longer than the shaft 5 and the conductive wire 20 is curved within the inner cavity of the shaft 5, the length of the exposed portion of the conductive wire 20 in the natural state may be shorter than the length of the conductive wire 20 when the conductive wire 20 is exposed from the shaft 5 by pulling the conductive wire 20 in the radial direction so that the exposed portion is at its longest.

A detailed method of fixing the tip of the conductive wire 20 to the shaft 5 will be described. The tip of the conductive wire 20 may be directly fixed to the shaft 5, or may be indirectly fixed via another member. In FIG. 2, a fixture 50 is disposed at the tip of the conductive wire 20. In this case, it is preferable that the fixture 50 contacts the inner wall of the first cavity 11 of the shaft 5. Since frictional resistance is generated by the fixture 50 abutting against the inner wall of the first cavity 11, it is possible to prevent the conductive wire 20 from coming out of the shaft 5 when the conductive wire 20 is advanced or retreated.

The fixture 50 has a tip and a base. The tip of the fixture 50 is located on the tip side of the conductive wire 20, and the direction from the tip to the base of the fixture 50 coincides with the direction from the tip to the base of the conductive wire 20. The shape of the fixture 50 is not particularly limited, and may be, for example, a rectangular column, a cylindrical column, an oblong cylindrical column, or a combination of these. The fixture 50 may have a portion whose outer diameter becomes smaller toward the tip. Examples of such shapes include truncated pyramid shapes, such as a truncated cone shape, a truncated cone shape, an oblong truncated cone shape, and a truncated cone shape with rounded corners.

The fixing device 50 can be made of the same resin as the shaft 5 or the same metal as the conductive wire 20. The fixing device 50 can also contain an X-ray opaque material. There are no particular limitations on the method of fixing the fixing device 50 to the conductive wire 20, but methods such as crimping, welding, and adhesion can be used.

When the conductive wire 20 has a non-exposed section 22 arranged in the first lumen 11, it is preferable that the cross-sectional shape of the cross section perpendicular to the longitudinal axis direction of the conductive wire 20 in the non-exposed section 22 is non-circular, for example, as shown in Figures 7 to 10. In detail, it is preferable that the cross-sectional shape of the cross section perpendicular to the longitudinal axis direction x of the conductive wire 20 in the first non-exposed section 221 is non-circular. By making the cross-sectional shape like this, frictional resistance occurs between the conductive wire 20 and the shaft 5 or the fixture 50, so that the conductive wire 20 can be prevented from rotating relative to the shaft 5 or the fixture 50. The cross-sectional shapes of the conductive wire 20 in the exposed section 21 and the non-exposed section 22 may be the same or different from each other.

In FIG. 1, the handle 65 has a first handle 66 connected to the base end of the conductive wire 20 and a second handle 68 connected to the proximal side of the shaft 5. The first handle 66 is arranged outside the second handle 68, but the second handle 68 may be arranged outside the first handle 66. The first handle 66 is configured to be movable relative to the second handle 68. By moving the first handle 66, the length and degree of bending of the exposed section 21 can be changed. The shaft 5 and the second handle 68 are connected via a connecting tube 60, and the tube 60 has a first inlet 61 for inserting a guide wire. The second handle 68 has a second inlet 67 for introducing a liquid into the second lumen 12 or the third lumen 13 of the shaft 5. The first handle 66 has a connection part 69 with a high-frequency power source. The shaft 5 and the second handle 68, or the conductive wire 20 and the first handle 66 may be directly connected to each other, or may be connected via another member such as the tube 60. These can be connected using methods such as thermocompression bonding or adhesive bonding.

1: High-frequency treatment tool 5: Shaft 20: Conductive wire 21: Exposed section 22: Non-exposed section 23: Short axis 24: Long axis 41: First position 42: Second position 50: Fixing device x: Longitudinal direction of shaft p: Circumferential direction of shaft

Claims (13)

The electromechanical device has a shaft and a conductive wire disposed within the shaft,
The shaft has a first opening and a second opening in order from the distal side on an outer circumferential surface of a distal portion thereof,
the conductive wire has an exposed section exposed to the outside of the shaft through the first opening and the second opening , a cross-sectional shape of the conductive wire taken along a cross section perpendicular to a longitudinal axis direction has a minor axis and a major axis, and a direction of the major axis varies depending on a position of the exposed section ;
A high-frequency treatment tool in which a tip portion of the conductive wire is fixed to the shaft . 2. The high-frequency treatment device according to claim 1, wherein, when the high-frequency treatment device is viewed from a proximal side in a longitudinal axial direction of the shaft, the conductive wire is twisted clockwise from a proximal side to a distal side in the exposed section . 2. The high-frequency treatment device according to claim 1, wherein, when the high-frequency treatment device is viewed from a proximal side in a longitudinal axis direction of the shaft, the conductive wire is twisted counterclockwise from a proximal side to a distal side in the exposed section . the conductive wire has an unexposed section disposed in a first lumen of the shaft;
4. The high-frequency treatment tool according to claim 1, wherein a direction of the major axis of the cross-sectional shape of the conductive wire varies depending on a position of the unexposed section. the conductive wire has an unexposed section disposed in a first lumen of the shaft;
4. The high-frequency treatment tool according to claim 1, wherein the direction of the major axis of the cross-sectional shape of the conductive wire is the same at any position in the unexposed section. the conductive wire has an unexposed section disposed in a first lumen of the shaft;
The non-exposed section includes a first non-exposed section distal to the exposed section and a second non-exposed section proximal to the exposed section,
The high-frequency treatment device according to any one of claims 1 to 3, wherein the direction of the long axis of the cross-sectional shape of the conductive wire varies depending on its position in the first non-exposed section, and is the same at any position in the second non-exposed section. the conductive wire has an unexposed section disposed in a first lumen of the shaft;
The non-exposed section includes a first non-exposed section distal to the exposed section and a second non-exposed section proximal to the exposed section ,
The high-frequency treatment instrument according to any one of claims 1 to 6, wherein a distal end of the second unexposed section of the conductive wire is in contact with a first circumferential end side of the second opening in the inner wall of the shaft. the conductive wire has an unexposed section disposed in a first lumen of the shaft;
The non-exposed section includes a first non-exposed section distal to the exposed section and a second non-exposed section proximal to the exposed section ,
The high-frequency treatment instrument according to any one of claims 1 to 6, wherein a distal end of the second unexposed section of the conductive wire is in contact with a second circumferential end side of the second opening in the inner wall of the shaft. The high-frequency treatment device according to claim 7 or 8, wherein the proximal end of the first unexposed section of the conductive wire is in contact with the first end side of the first opening in the inner wall of the shaft in the circumferential direction. The high-frequency treatment device according to any one of claims 1 to 9, wherein in a cross section perpendicular to the longitudinal axis of the shaft in the exposed section of the conductive wire, a straight line connecting the centroid of the shaft and the centroid of the conductive wire is parallel to the short axis of the conductive wire. the conductive wire has an unexposed section disposed in a first lumen of the shaft;
The high-frequency treatment tool according to any one of claims 1 to 10, wherein a cross section perpendicular to a longitudinal axis direction of the conductive wire in the unexposed section has a non-circular shape. The high-frequency treatment device according to any one of claims 1 to 11, wherein the shaft has a first inner cavity and a second inner cavity, and the tip of the conductive wire is disposed in the first inner cavity. The high-frequency treatment device according to claim 12, further comprising a fixture disposed at the tip of the conductive wire and in contact with the inner wall of the first cavity.

Images