High-frequency incision instrument for an endoscope

Abstract

High-frequency incision instrument for an endoscope, with: - a flexible, insulating tube (1, 2A, 2B) that can be inserted into and withdrawn from an instrument channel of the endoscope; - a conductive wire (3) which can be connected to a high-frequency power supply and is inserted into the flexible, insulating tube (1, 2A, 2B); - a distally projecting portion formed at the distal end of the flexible, insulating tube (1, 2A, 2B), which has a rounded leading edge (2E); and - a single high-frequency electrode (5) formed by a portion of the conductive wire (3) exposed extending from the flexible insulating tube (1, 2A, 2B) and having at least one section closest to the leading edge (2E) of the protruding part, which is substantially perpendicular to a virtual plane (X) in which the longitudinal axis of the flexible insulating tube (1, 2A, 2B) and the leading edge (2E) of the protruding part lie, wherein the high-frequency electrode (5) is located in a first half of the distal end of the flexible insulating tube (1, 2A, 2B) when viewed in the direction of the distal end of the flexible insulating tube (1, 2A, 2B), while the rounded leading edge (2E) of the protruding part is located in a second half of the distal end of the flexible insulating tube (1, 2A, 2B) opposite the first half.

Description

[0001] The invention relates to a high-frequency incision instrument that allows high-frequency incision treatment to be carried out safely.

[0002] As a high-frequency incision instrument for an endoscope used to cut a raised part of a near-surface mucosal region in a body cavity using high-frequency cautery, an incision instrument having a high-frequency electrode in the shape of a straight or curved rod projecting from the distal end of a flexible tube or an incision instrument having a conductive wire as a high-frequency electrode arranged in a crisscross arrangement on a leading edge portion of a front cap of an endoscope is commonly used (see, for example, JP 2002 - 153 485 A and JP 2005 - 66 140 A).

[0003] If a raised part of the near-surface mucosal area in the body cavity is cut, it is desirable from a safety point of view to cauterize and thus cut only the mucosal area without simultaneously cauterizing the muscle layer lying beneath the mucosal area.

[0004] However, a conventional high-frequency incision instrument has the problem that its distal end, equipped with the high-frequency electrode, approaches the muscle layer underlying the mucosal area contrary to the user's intention, thus causing cauterization and damage to the area surrounding the muscle layer. This is because the high-frequency incision instrument, which is pressed during cauterization treatment, can be easily advanced toward the cauterized tissue through the area of ​​cauterized tissue evenly distributed around the high-frequency electrode, encountering little resistance to the advancement of the high-frequency incision instrument.

[0005] An endoscopic high-frequency incision instrument for performing minimally invasive surgeries is known from US 2005 / 0 049 454 A1. This instrument features a transparent cap with a cylindrical rear section that is attached to the distal end of the endoscope. The front section of the cap allows visual monitoring of the surgical area through the endoscope. The transparent cap has tubes on its front side through which the leg sections of a U-shaped high-frequency electronic unit are guided.

[0006] The object of the invention is to provide an improved high-frequency incision instrument for an endoscope, which ensures that the distal end of the high-frequency incision instrument is brought closer to a muscle layer lying beneath the mucosal region, contrary to the user's intention when the user presses on the instrument when cauterizing a raised part of the near-surface mucosa, so that the user can safely perform the high-frequency incision treatment.

[0007] The invention solves this problem by the high-frequency incision instrument according to claim 1. Advantageous further developments are specified in the subclaims.

[0008] The invention is explained in more detail below with reference to the figures, in which: Fig. 1 shows a longitudinal section through a distal end part of a high-frequency incision instrument intended for an endoscope according to a first embodiment; Fig. 2 a plan view of the high-frequency incision instrument according to the first embodiment; Fig. 3 a front view of the high-frequency incision instrument according to the first embodiment; Fig. 4 is a side view showing the overall structure of the high-frequency incision instrument according to the first embodiment; Fig. 5 is a side view showing the overall structure of the high-frequency incision instrument according to the first embodiment in an operating state; Fig. 6 is a longitudinally sectioned plan view of the distal end portion of the high-frequency incision instrument according to the first embodiment in an operating state; Fig. 7 to 10 are views showing successive phases of a percutaneous endoscopic treatment in which a raised mucosal area is incised using the high-frequency incision instrument according to the first embodiment; Fig. 11 is a longitudinally sectioned plan view of the distal end portion of a high-frequency incision instrument for an endoscope according to a second embodiment; Fig. 12 is a side view of the distal end portion of the high-frequency incision instrument according to the second embodiment; Fig. 13 is a front view of the distal end portion of the high-frequency incision instrument according to the second embodiment; Fig. 14 is a plan view of the distal end portion of a high-frequency incision instrument for an endoscope according to the third embodiment; Fig. 15 is a side view of the distal end portion of the high-frequency incision instrument according to the third embodiment; Fig. 16 is a front view of the distal end portion of the high-frequency incision instrument according to the third embodiment; and Fig. 17 a side view of the distal end part of a high-frequency incision instrument intended for an endoscope according to the fourth embodiment Description of the embodiments

[0009] Embodiments of the invention are described below with reference to the figures. Fig. 1, Fig. 2 and Fig. 3 is a longitudinal section, a plan view, and a front view of a distal end portion of a high-frequency incision instrument for an endoscope according to a first embodiment.

[0010] The reference numerals 1, 2A and 2B in Fig. 1 denotes a flexible tube having a diameter of, for example, about 2 mm, which can be inserted into and withdrawn from an instrument channel (not shown) of the endoscope and is made of an electrically insulating synthetic resin such as ethylene tetrafluoride resin.

[0011] A rear tube 1, which forms part of the aforementioned flexible tube, is a comparatively long tube, the total length of which is approximately 1 to 2 meters. In contrast, the front tubes 2A and 2B, which also each form part of the flexible tube, are shorter tubes, each having a total length of several centimeters. The front tubes 2A and 2B are laminated and integrally assembled at a connecting portion to form a locking step (stepped stopper) 2C, which can be firmly pressed into the distal end of the rear tube 1. The front tubes 2A and 2B can thus be formed as a single thermoformed tube.

[0012] The front tubes 2A and 2B are provided with a section that extends backwards (in Fig. 1 right) is loosely inserted into the rear tube 1. In a state where the locking step 2C is not pressed into the distal end of the rear tube, the front tubes 2A and 2B can slide forward and backward and rotate relative to the rear tube 1 about the longitudinal axis of the flexible tube composed of parts 1, 2A, and 2B. In contrast, in a state where the locking step 2C is pressed into the distal end of the rear tube 1, the front tubes 2A and 2B are fixed to the rear tube 1 with a certain force.

[0013] The rear tube 1 is formed to have a constant diameter along its entire length. However, the rear tube 1 is elastically deformed such that its distal end portion, into which the locking step 2C of the front tubes 2A and 2B is pressed, expands, increasing its diameter.

[0014] A flexible, conductive wire 3 is inserted into the flexible tube 1, 2A, and 2B along its entire length. The wire 3 can be connected to a high-frequency power supply at the rear end of the flexible tube 1, 2A, 2B and can be retracted and advanced along the longitudinal axis of the flexible tube 1, 2A, 2B, as well as rotated about the longitudinal axis. Reference numeral 3a denotes a cover tube for the high-frequency electrode 3.

[0015] The distal end of the front tube 2A has a forward protruding portion. In the first embodiment, a distal end or end surface 2D of the front tube 2A has a slant-cut shape and has a rounded leading edge portion (end portion) 2E.

[0016] As in Fig. 3, the leading edge portion 2E of the front tube 2A is located on the lower side of the front tube 2A when viewed from the front. Fig. 3, the dashed line X denotes a virtual plane in which the longitudinal axis of the front tube 2A and the leading edge portion 2E lie.

[0017] As in the Fig. 1 and Fig. As shown in Figure 2, in a region adjacent to the distal end face 2D on the upper outer peripheral surface of the distal end portion of the front tube 2A, two openings 4 are provided symmetrically with respect to the virtual plane X, which openings are formed so that the conductive wire 3 can be passed through them. The wire 3 is thus exposed along the outer peripheral surface of the front tube 2A between the two openings 4.

[0018] The part of the conductive wire 3 that is exposed between the two openings 4 on the outer peripheral surface serves as a high-frequency electrode 5, with which high-frequency cauterization can be performed. As shown in Fig. 3, the high-frequency electrode 5 is therefore not located on the lower outer peripheral surface of the front tube 2A, that is, on the side near the leading edge portion 2E. The high-frequency electrode 5 is arranged substantially perpendicular to the virtual plane X.

[0019] As in Fig. 1, an end portion 3b of the conductive wire 3, which is withdrawn through the two openings 4 in the front tubes 2A and 2B, is wound around and fixed to an insulating tube 6 covering the conductive wire 3.

[0020] Fig. Figure 4 shows the overall structure of the high-frequency incision instrument designed for an endoscope. As shown in Fig. 4, a pipe sleeve 7, which is attached to the rear end of the pipe 1, has a supply sleeve 8 that projects laterally and can be connected to a syringe. A rinsing fluid can be supplied via the supply sleeve 7, which is transported through the cavity of the flexible pipe 1, 2A, and 2B and sprayed out of the opening of the distal end of the front pipe 2A.

[0021] The pipe sleeve 7 is connected to an operating unit 10. The operating unit 10 has a fixed finger part 12 attached to one end of a body 11 of the operating unit 10, which is connected to the pipe sleeve 7 and is rotatable about the longitudinal axis of the pipe sleeve 7. The operating unit 10 further has a movable finger part 13 attached to the body 11 and movable back and forth along the longitudinal axis of the body 11.

[0022] The rear end of the conductive wire 3, designated 3a, is firmly connected to the movable finger part 13. A terminal 14, which can be connected to a high-frequency power cable (not shown), is attached to the movable finger part 13. By connecting the high-frequency power cable to the terminal 14, the high-frequency electrode 5 can be supplied with a high-frequency current via the conductive wire 3.

[0023] If, in the construction described above, the movable finger part 13 is pushed forward, as in Fig. 5 is indicated by the arrow A, the locking stage 2C of the front tubes 2A and 2B is pushed forward from the inside of the rear tube 1, as shown in the Fig. 5 and Fig. 6 is indicated by the arrow B, whereby the front tubes 2A and 2B are released, ie come into a state in which they are not attached to the rear tube 1.

[0024] If in this state the entire control unit 10 is rotated around the longitudinal axis of the pipe socket 7, as in Fig. 5 is indicated by the arrow C, the front tubes 2A and 2B are rotated around the longitudinal axis of the rear tube 1, as shown in the Fig. 5 and Fig. 6 is indicated by arrow D. This makes it possible to adjust the relative arrangement between the rear tube 1 and the high-frequency electrode 5 in the direction of rotation as desired. After this adjustment is completed, the locking step 2C is pushed back into the rear tube 1, thereby securing the front tubes 2A and 2B to the rear tube 1.

[0025] The Fig. 7 to 10 show successive states in which, in a percutaneous endoscopic treatment, a raised mucosal region 101 is incised using the high-frequency incision instrument for an endoscope constructed as described in the first embodiment. As shown in Fig. As shown in Fig. 7, first, the leading or distal edge portion 2E of the flexible tube 1, 2A, and 2B, which is inserted into the instrument channel 51, is pressed to a position near the base of the raised mucosal region 101. At this time, the orientation of the front tubes 2A and 2B in the rotational direction has been previously adjusted such that the leading edge portion 2E faces a muscle layer 102, while the high-frequency electrode 5 faces away from the muscle layer 102.

[0026] Then, the high-frequency electrode 5 is supplied with a high-frequency current, whereby the tissue of the raised mucous membrane area 101 around the point where it is in contact with the high-frequency electrode 5 is cauterized and thus incised, as shown in Fig. 8. In contrast, the tissue in an area closer to the muscle layer 102 than the leading edge portion 2E is cauterized only to a slight extent, if at all, since this area is located away from the high-frequency electrode 5.

[0027] If then, as in Fig. 9, the flexible tube 1, 2A, and 2B is pushed forward, the leading edge portion 2E is advanced along the tissue. However, the leading edge portion 2E can be prevented from approaching the muscle layer 102 contrary to the user's intention, since the tissue area closer to the muscle layer 102 than the leading edge portion 2E is not cauterized.

[0028] If the high-frequency electrode 5 is then supplied with high-frequency current again, the tissue of the raised mucous membrane area 101 is cauterized and incised around a point that is in contact with the high-frequency electrode 5, as shown in Fig. 10. This reliably incises the raised mucosal region 101 around its base without the cauterized region approaching the muscle layer 102.

[0029] The Fig. 11 to 13 show a longitudinally sectioned plan view, a side view, and a front view of a distal end portion of a high-frequency incision instrument for an endoscope according to the second embodiment. Fig. As shown in Figures 11 to 13, a high-frequency electrode 5 is exposed at a distal end surface 2D of a front tube 2A between two openings 4 and is arranged over its entire length substantially perpendicular to the virtual plane X. With this construction, the same technical effects as in the first embodiment are achieved.

[0030] The Fig. 14 to 16 show a plan view, a side view, and a front view of a distal end portion of a high-frequency incision instrument for an endoscope according to the third embodiment. As shown in FIGS. Fig. As shown in Figures 14 to 16, a high-frequency electrode 5 is formed in a substantially U-shape and arranged such that two parallel portions of the U-shaped electrode 5 along a distal end surface 2D are parallel to the virtual plane X, while a bridge portion located between these parallel portions of the U-shaped electrode 5 is arranged substantially perpendicular to the virtual plane X. With this construction, the same technical effects as in the first embodiment are achieved.

[0031] Fig. 17 is a side view of a distal end portion of a high-frequency incision instrument for an endoscope according to the fourth embodiment. As shown in Fig.As shown in Figure 17, a front tube 2A has a distal end portion formed with a tongue-shaped protrusion and a rounded leading edge portion 2E. A high-frequency electrode 5 is disposed therein as described in the first embodiment. This construction achieves the same technical effects as the first embodiment.

Claims

[1] High-frequency incision instrument for an endoscope, comprising: - a flexible, insulating tube (1, 2A, 2B) which can be inserted into and withdrawn from an instrument channel of the endoscope; - a conductive wire (3) connectable to a high-frequency power supply and inserted into the flexible insulating tube (1, 2A, 2B); - a distally projecting portion formed at the distal end of the flexible insulating tube (1, 2A, 2B) and having a rounded leading edge (2E); and - a single high-frequency electrode (5) formed by a part of the conductive wire (3) exposed from the flexible, insulating tube (1, 2A, 2B), and having at least one portion closest to the leading edge (2E) of the projecting part, which portion is substantially perpendicular to a virtual plane (X) in which the longitudinal axis of the flexible, insulating tube (1, 2A, 2B) and the leading edge (2E) of the projecting part lie, wherein the high-frequency electrode (5) is located in a first half of the distal end of the flexible, insulating tube (1, 2A, 2B) as viewed toward the distal end of the flexible, insulating tube (1, 2A, 2B), while the rounded leading edge (2E) of the projecting part is located in a second half of the distal end of the flexible, insulating tube (1, 2A, 2B) opposite the first half. [2] A high-frequency incision instrument according to claim 1, wherein the projecting part has an obliquely cut shape, the distal end of which forms the rounded leading edge (2E). [3] A high-frequency incision instrument according to claim 1, wherein the projecting part has a tongue shape whose distal end forms the rounded leading edge (2E). [4] High-frequency incision instrument according to one of claims 1 to 3, further comprising a pair of openings (4) arranged circumferentially adjacent to each other on the outer peripheral surface of the distal end of the flexible insulating tube (1, 2A, 2B) and formed such that the conductive wire (3) can be passed through the openings (4), - wherein the high-frequency electrode (5) is led out of the insulating tube (1, 2A, 2B) through the two openings (4) and is exposed between the two openings (4) along the outer peripheral surface of the first half of the distal end of the flexible insulating tube (1, 2A, 2B). [5] High-frequency incision instrument according to claim 4, wherein the two openings (4) are arranged symmetrically to the virtual plane (X). [6] High-frequency incision instrument according to one of the preceding claims, wherein the high-frequency electrode (5) is designed such that it is arranged substantially perpendicular to the virtual plane (X) over its entire length. [7] High-frequency incision instrument according to claim 5, wherein the high-frequency electrode (5) is substantially U-shaped and has two first sections arranged along a distal end surface (2D) of the flexible, insulating tube (1, 2A, 2B) substantially parallel to the virtual plane (X), and a second section arranged between the two first sections substantially perpendicular to the virtual plane (X). [8] High-frequency incision instrument according to one of the preceding claims, wherein the flexible, insulating tube (1, 2A, 2B) comprises a first tube (2A, 2B) and a second tube (1), and the first tube (2A, 2B) is connected to the second tube (1) in such a way that it is rotatable about the longitudinal axis of the flexible, insulating tube (1, 2A, 2B) relative to the second tube (1).

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