Endoscope

Abstract

To provide an endoscope capable of appropriately bringing a part of an ultrasonic vibrator array into contact with an object part.SOLUTION: An endoscope includes an insertion portion including a distal end portion including an ultrasonic vibrator array and a bending portion provided on a proximal end side of the distal end portion, and a bending operation portion capable of performing a bending operation of the bending portion. The bending portion includes a first region and a second region between the first region and the distal end portion. The first region is bent on a surface side of the distal end portion on which the ultrasonic vibrator array is provided when the bending operation portion is operated in a first range. The second region is held in a state of extending along an axis of the distal end portion when the bending operation portion is operated in the first range.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to an endoscope. [Background technology]

[0002] Patent Documents 1, 3, 5 and 6 describe endoscopes having a bending portion that can bend the distal end portion more than the proximal end portion.

[0003] Patent Document 2 describes an endoscope having a bending portion that can be bent with a plurality of curvature radii.

[0004] Patent Document 4 describes that in a bending section structure of an endoscope configured by connecting a plurality of nodal rings along the axial direction of an insertion section, the plurality of nodal rings are connected such that the distance between adjacent nodal ring bodies gradually increases from the base end side of the bending section to the tip end side of the bending section. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-334050 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-154545 [Patent Document 3] Japanese Patent Application Publication No. 02-271817 [Patent Document 4] Japanese Patent Application Laid-Open No. 2000-342517 [Patent Document 5] Japanese Utility Model Application Publication No. 56-124401 [Patent Document 6] Japanese Patent Application Publication No. 11-155806 [Patent Document 7] International Publication No. 2022 / 153798 Summary of the Invention [Problem to be solved by the invention]

[0006] The technology disclosed herein provides an endoscope that can appropriately bring a portion of an ultrasound transducer array into contact with a target site. [Means for solving the problem]

[0007] An endoscope according to one aspect of the disclosed technology comprises an insertion section including a tip section including an ultrasonic transducer array and a bending section provided on the base end side of the tip section, and a bending operation section capable of bending the bending section, wherein the bending section includes a first region and a second region between the first region and the tip section, and when the bending operation section is operated in a first range, the first region bends toward the surface of the tip section on which the ultrasonic transducer array is provided, and when the bending operation section is operated in the first range, the second region is maintained in an extended state along the axis of the tip section. [Effects of the Invention]

[0008] According to the technique of the present disclosure, a portion of the ultrasound transducer array can be brought into appropriate contact with the target area. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is an overall view of an ultrasonic endoscope 1 as an endoscope according to one embodiment of the disclosed technique. [Figure 2] FIG. 2 is a perspective view of the distal end rigid portion 34 of the first embodiment. [Figure 3] FIG. 3 is an exploded perspective view of the distal end rigid portion 34 of the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view of the distal end rigid portion 34 of the first embodiment. [Figure 5] FIG. 5 is a perspective view of the distal end rigid portion 34 including the tangent line LT. [Figure 6] FIG. 6 is a side view of the distal end rigid portion 34 including the tangent line LT. [Figure 7] FIG. 7 is a cross-sectional view of a modified distal end rigid portion 34. As shown in FIG. [Figure 8] FIG. 8 is a perspective view schematically showing the main part of the bending portion 32 of the endoscope 1 shown in FIG. [Figure 9] FIG. 9 is an enlarged perspective view of the first movable member 32A shown in FIG. [Figure 10] FIG. 10 is an enlarged perspective view of the second movable member 32B shown in FIG. [Figure 11] FIG. 11 is a diagram schematically illustrating the bending portion 32 shown in FIG. 8 as viewed in the X direction. [Figure 12] FIG. 12 is a schematic diagram for explaining the bent state of the bending portion 32 when the angle lever 16 is rotated in the A1 direction from the state shown in FIG. [Figure 13] FIG. 13 is a schematic diagram for explaining the state in which the endoscope 1 is inserted into the bronchi and used. [Figure 14] FIG. 14 is a schematic diagram for explaining the bent state of the bending portion 32 when the rotation angle of the angle lever 16 is increased from the state shown in FIG. [Figure 15] FIG. 15 is a schematic diagram for explaining the state in which the endoscope 1 is inserted into the bronchi and used. [Figure 16] FIG. 16 is a schematic diagram for explaining the bent state of the bending portion 32 when the angle lever 16 is rotated in the −A1 direction from the state shown in FIG. [Figure 17] FIG. 17 is a schematic diagram for explaining another state in which the endoscope 1 is inserted into the bronchi and used. DETAILED DESCRIPTION OF THE INVENTION

[0010] Figure 1 is an overall view of an ultrasound endoscope 1 as an endoscope according to one aspect of the technology of the present disclosure. As shown in Figure 1, the ultrasound endoscope 1 (hereinafter simply referred to as "endoscope 1") is used to collect cellular tissue from a lesion (which may also be an observation site, an examination site, or an examination site). In this embodiment, a bronchial lymph node will be used as an example of the lesion.

[0011] The endoscope 1 is composed of an operation section 10 that is held by the surgeon to perform various operations, an insertion section 12 that is inserted into the patient's body, and a universal cord 14. The endoscope 1 is connected via the universal cord 14 to system component devices such as a processor device and a light source device (not shown) that constitute an endoscope system.

[0012] The operation unit 10 is provided with various operation members that are operated by the practitioner, such as an angle lever 16 and a suction button 22, the operation of which will be described later as appropriate.

[0013] The operation section 10 is also provided with a treatment tool introduction port 24 for inserting a treatment tool into a treatment tool insertion channel 23 (see FIG. 4) that passes through the insertion section 12.

[0014] The insertion section 12 extends from the tip of the operation section 10 and is formed in a long shape with a small diameter as a whole. The insertion section 12 is configured by providing, in order from the base end side to the tip end side, a flexible section 30, a bending section 32, and a tip rigid section 34 which is the tip end.

[0015] The flexible section 30 occupies the majority of the proximal end side of the insertion section 12 and has flexibility that allows it to bend in any direction. When the insertion section 12 is inserted into a body cavity, the flexible section 30 bends along the insertion path into the body cavity.

[0016] The bending portion 32 is adapted to bend in the vertical direction (A2 direction and its opposite -A2 direction) by rotating the angle lever 16 of the operating unit 10 in the A1 direction and its opposite -A1 direction, and by bending the bending portion 32, the tip rigid portion 34 can be directed in the desired direction.

[0017] The angle lever 16 is configured to be rotatable in the A1 direction up to a rotation angle of 45°, with the state shown in Fig. 1 being a rotation angle of 0°. Rotating the angle lever 16 in the A1 direction causes the bending portion 32 to bend in the A2 direction (upward). The angle lever 16 is configured to be rotatable in the -A1 direction up to an angle smaller than the rotation angle of 45° (for example, 25°). Rotating the angle lever 16 in the -A1 direction causes the bending portion 32 to bend in the -A2 direction (downward). The angle lever 16 constitutes a bending operation unit that can bend the bending portion 32.

[0018] The tip rigid portion 34 will be described in detail using Figures 2 to 4 below, and is equipped with an observation optical system 40 and an illumination optical system 44 for taking observation images of the inside of the body, an ultrasonic transducer 50 for acquiring ultrasonic images, and an outlet 52 for guiding the treatment tool inserted from the treatment tool inlet 24.

[0019] The universal cord 14 contains a signal cable 54, a signal cable 56, and a light guide 58, the details of which are shown in Figures 3 and 4 described below. A connector is provided at an end (not shown) of the universal cord 14. This connector is connected to predetermined system component devices that constitute an endoscope system, such as a processor device and a light source device. As a result, the system component devices supply the endoscope 1 with power, control signals, illumination light, and the like required for operating the endoscope 1. Conversely, data of observation images acquired by the observation optical system 40 and data of ultrasound images acquired by the ultrasound transducer 50 are transmitted from the endoscope 1 to the system component devices. The observation images and ultrasound images transmitted to the system component devices are displayed on a monitor so that they can be observed by a practitioner, etc.

[0020] The configuration of the operating unit 10 is not limited to the embodiment shown in Fig. 1. An angle knob may be provided instead of the angle lever 16, or a pair of angle levers 16 or angle knobs may be provided, and the bending portion 32 may be bent in the up-down direction (A2 direction and -A2 direction) and the left-right direction perpendicular thereto by rotating the pair of angle levers 16 or the pair of angle knobs. Also, an air and water supply button may be provided on the operating unit 10, and a gas such as air and a cleaning liquid may be supplied to the rigid tip portion 34 by operating the air and water supply button.

[0021] Fig. 2 is a perspective view of the tip rigid portion 34. Fig. 3 is an exploded perspective view of the tip rigid portion 34. Fig. 4 is a cross-sectional view of the tip rigid portion 34.

[0022] The Z direction in the drawing is a direction parallel to the longitudinal axis 38 of the insertion section 12. The Z direction constitutes the longitudinal axis direction of the insertion section 12. The Z(+) direction side, which is one of the Z directions in the drawing, is the tip side of the insertion section 12, and the Z(-) direction side is the base end side of the insertion section 12. The Y direction in the drawing is a first direction perpendicular to the Z direction (in other words, perpendicular to the longitudinal axis 38), and corresponds to the A2 direction and -A2 direction in Figure 1. The Y(+) direction, which is one of the Y directions, is the A2 direction in Figure 1, and the Y(-) direction, which is the other of the Y directions, is the -A2 direction in Figure 1. The X direction in the drawing is a second direction perpendicular to both the Z direction and the Y direction.

[0023] 2 to 4, the tip rigid section 34 is configured by combining an ultrasound block component 60, a channel block component 70, and an optical system block component 80 (see FIG. 3 in particular). When the block components are combined, the tip rigid section 34 comprises, from the tip side to the base end side of the tip rigid section 34, an ultrasound attachment section 34a, an outlet forming section 34b, and a main body section 34c (see FIGS. 2 and 4).

[0024] The ultrasound block component 60 is formed from an insulating material having insulating properties, for example, a resin material such as a plastic, such as polysulfone or polyetherimide. From its distal end toward its proximal end, the ultrasound block component 60 includes an ultrasound mounting portion 34a and an optical system block component mounting portion 62 (see FIG. 3). The ultrasound mounting portion 34a and the optical system block component mounting portion 62 are integrally formed.

[0025] When the distal end rigid portion 34 is viewed from the X-direction side, the ultrasonic transducer 50 is attached to the ultrasonic attachment portion 34a in a position tilted forward (inclined) in the Y (-) direction with respect to the longitudinal axis 38. This ultrasonic transducer 50 is a convex type having an ultrasonic transmission / reception surface in which ultrasonic vibrators that transmit and receive ultrasonic waves are arranged in a curved shape along the direction of the longitudinal axis 38. This ultrasonic transducer 50 acquires data to generate an ultrasonic image of the lymph node. The ultrasonic transducers 50 form an ultrasonic vibrator array. The number of ultrasonic vibrators that make up the ultrasonic transducer 50 is not limited.

[0026] Furthermore, when the distal end rigid portion 34 is viewed from the X direction side, the optical system block component mounting portion 62 extends from the Y(-) direction side region of the proximal end of the ultrasound mounting portion 34a toward the proximal end side [Z(-) direction side] of the ultrasound mounting portion 34a. Furthermore, a locking portion 64 that locks with a locked portion 73 of a channel block component 70 (described later) is formed in the Y(+) direction side region of the proximal end of the ultrasound mounting portion 34a (see FIG. 4). The locking portion 64 has, for example, a locking claw that forms a snap fit.

[0027] The optical system block component mounting portion 62 has a generally semi-cylindrical shape corresponding to the Y(-) direction split portion, i.e., the lower half split portion, of the two split portions obtained by splitting the outlet forming portion 34b and the main body portion 34c in the Y direction (upper and lower halves) (see FIG. 3). Therefore, the optical system block component mounting portion 62 has a mounting portion opening 65 that opens to the Y(+) direction side.

[0028] The mounting portion opening 65 is formed parallel to the XZ plane and along the Z direction. Inside the mounting portion opening 65 of the optical system block component mounting portion 62, a signal cable 54 is arranged, which connects the ultrasonic transducer 50 to the above-described system component device.

[0029] The optical system block component mounting portion 62 is formed with a pair of guide portions 66 that form a mounting portion opening 65 and extend in the Z(-) direction along the mounting portion opening 65. An optical system block component 80 (described below) is mounted to the pair of guide portions 66 while sliding in the Z direction. In this way, the optical system block component 80 is mounted to the optical system block component mounting portion 62, i.e., the ultrasound block component 60, via the pair of guide portions 66.

[0030] The channel block component 70, together with the optical system block component 80 described below, constitutes the outlet forming portion 34b, and is made of a known metal material. The channel block component 70 has a treatment tool outlet 52 that opens on the Y(+) direction side, and a substantially rectangular opening forming surface 71 that is parallel to the XZ plane in which the outlet 52 opens and that extends along the Z direction (including the longitudinal axis 38, the same applies below). In this embodiment, a puncture needle 100 used to collect lymph node tissue will be described as an example of the treatment tool.

[0031] A pair of flange surfaces 72 parallel to the XZ plane are formed along the Z direction at both ends of the opening forming surface 71 in the X direction (see FIG. 3). The pair of flange surfaces 72 are used to attach the channel block component 70 to the optical system block component 80, and extend outward (in the X direction) from both ends of the opening forming surface 71 in the X direction.

[0032] Furthermore, a locked portion 73 that engages with the locking portion 64 of the ultrasonic mounting portion 34a is formed on the tip side of the channel block component 70 (see FIGS. 3 and 4). The locked portion 73 has, for example, an engagement hole that engages with the locking claw of the locking portion 64.

[0033] As shown in Fig. 4, an intra-block duct 74 is formed inside the channel block component 70. The intra-block duct 74 constitutes a duct together with the treatment tool insertion channel 23. The distal end side of this intra-block duct 74 is connected to the outlet 52, and the proximal end side of the intra-block duct 74 is connected to the treatment tool insertion channel 23 inserted through the insertion section 12. As a result, the distal end of the puncture needle 100 inserted from the treatment tool introduction port 24 is guided through the treatment tool insertion channel 23 and the intra-block duct 74 to the outlet 52, and then led out from the outlet 52 to the outside.

[0034] The optical system block component 80 is made of a resin material, similar to the ultrasound block component 60. The optical system block component 80 has a shape corresponding to the divided part on the Y(+) direction side, i.e., the divided part on the upper half side, of the two divided parts obtained by dividing the outlet forming part 34b and the main body part 34c in the Y direction (upper and lower halves).

[0035] The optical system block component 80 includes a pair of channel block component mounting portions 81 and an optical system housing portion 82, which are spaced apart in the X direction from the distal end toward the proximal end (see FIG. 3). The pair of channel block component mounting portions 81 and the optical system housing portion 82 are integrally formed.

[0036] When the optical system block component 80 is viewed from the X-direction side, the pair of channel block component mounting portions 81 extend from a position one step lower than the vertex on the Y(+) direction side of the optical system storage section 82, i.e., from a position on the Y(-) direction side of the vertex, to the tip side [Z(+) direction side] of the optical system storage section 82.

[0037] A space for attaching the channel block component 70 is secured between the pair of channel block component attachment portions 81. A pair of flat surfaces 81a and a pair of support surfaces 81b are formed at the ends of the pair of channel block component attachment portions 81 on the Y(+) direction side (see FIG. 3). The pair of flat surfaces 81a are parallel to the XZ plane and have a shape along the Z direction.

[0038] The pair of support surfaces 81b are parallel to the pair of flat surfaces 81a. The pair of support surfaces 81b are shifted toward the space from the pair of flat surfaces 81a, and are positioned lower in the Y(-) direction than the pair of flat surfaces 81a by the thickness of the pair of flange surfaces 72 in the Y direction.

[0039] The pair of support surfaces 81b support the pair of flange surfaces 72 from both sides in the X direction. Therefore, the channel block component 70 is supported between the pair of channel block component mounting portions 81 so as to be slidable in the Z direction via the pair of flange surfaces 72 and the pair of support surfaces 81b. This allows the channel block component 70 to be mounted on the optical system block component 80 while sliding in the Z direction. The channel block component 70 is then adhesively fixed to the optical system block component 80.

[0040] When the channel block component 70 is attached to the optical system block component 80, the opening forming surface 71 and the pair of flat surfaces 81a form a continuous flat surface 90 (constituting the first surface) (see FIG. 2). The continuous flat surface 90 is a surface parallel to the XZ plane and along the Z direction, and constitutes part of the outer peripheral surface of the tip rigid portion 34. Note that in this embodiment, the continuous flat surface 90 is flat, but it may be a surface of various shapes such as a curved surface, an inclined surface, or an uneven surface.

[0041] The optical system housing section 82 has a substantially semi-cylindrical shape and has a convex surface 84 and a stepped surface 85. The convex surface 84 constitutes the second surface and constitutes part of the outer peripheral surface of the tip rigid section 34 (optical system housing section 82). This convex surface 84 is located on the Y(+) direction side of the continuous plane 90 and has a shape that follows the Z direction. Note that the convex surface 84 may also be formed into various shapes such as a curved surface, an inclined surface, or an uneven surface.

[0042] The step surface 85 is an inclined surface that connects the base end side of the continuous flat surface 90 and the tip side of the convex surface 84, and constitutes part of the outer peripheral surface of the tip rigid portion 34. Note that the inclined surface here also includes a vertical surface with an inclination angle of 90° with respect to the Z direction.

[0043] The step surface 85 is provided with an observation window 40 a of the observation optical system 40 and illumination windows 44 a of the pair of illumination optical systems 44 .

[0044] The observation optical system 40 includes an observation window 40a provided in the stepped surface 85, and a lens system 40b and an image pickup element 40c provided in the optical system housing portion 82. The image pickup element 40c is a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) image sensor, and captures an observation image captured from the observation window 40a via the lens system 40b. The image pickup element 40c then outputs an image pickup signal of the observation image to the system configuration device via a signal cable 56 inserted inside the insertion portion 12.

[0045] The illumination optical systems 44 are provided on both sides of the observation optical system 40 in the X direction, and include illumination windows 44a provided in the step surface 85 and light guides 58 inserted into the insertion section 12. The exit ends of the light guides 58 are disposed behind each illumination window 44a. As a result, illumination light supplied from the system component to each light guide 58 is emitted from each illumination window 44a.

[0046] With the channel block component 70 attached, the optical system block component 80 is attached by sliding it in the Z direction relative to the optical system block component attachment portion 62 of the ultrasound block component 60 via the pair of guide portions 66. At this time, the locking portion 64 of the ultrasound attachment portion 34a locks the locked portion 73 of the channel block component 70. This restricts movement of the channel block component 70 and the optical system block component 80 in the Z direction relative to the ultrasound block component 60, and the channel block component 70 is assembled to the ultrasound block component 60.

[0047] Furthermore, the distal end of the bending portion 32 is fitted and fixed to the proximal end of both the optical system housing portion 82 and the optical system block component mounting portion 62 (see FIG. 4). As a result, the optical system housing portion 82 and the optical system block component mounting portion 62 are held inseparably in the Y direction by the bending portion 32. As a result, the optical system block component 80 is assembled to the ultrasound block component 60.

[0048] As described above, the ultrasound block component 60, the channel block component 70, and the optical system block component 80 are combined to form the distal end rigid portion 34. In this distal end rigid portion 34, the ultrasound transducer 50, the outlet 52, and the stepped surface 85 (observation window 40a) are arranged in this order from the distal end toward the proximal end. That is, the outlet 52 is arranged between the ultrasound transducer 50 and the observation window 40a. Therefore, the puncture of the lymph node from the bronchial wall by the puncture needle 100 can be observed with the observation optical system 40.

[0049] The distal end rigid portion 34 of this embodiment has a shape that can increase the contact area of ​​the base end portion on the Z(-) direction side of the ultrasonic transducer 50 with the bronchial wall surface, i.e., the base end portion on the outlet 52 side from which the puncture needle 100 is led out, when an ultrasonic image of a lymph node is obtained using the endoscope 1. This shape will be specifically described below.

[0050] Fig. 5 is a perspective view of the tip rigid portion 34 including the tangent line LT. Fig. 6 is a side view of the tip rigid portion 34 including the tangent line LT. As shown in Figs. 5 and 6, in this embodiment, the shape of the tip rigid portion 34 that can increase the contact area of ​​the base end of the ultrasonic transducer 50 with the bronchial wall surface is defined using the tangent line LT and the effective angle θ1 of the ultrasonic transducer 50.

[0051] The tangent line LT is a line that is tangent to the ultrasonic transducer 50 and is tangent to the step surface 85 at a position (vertex) closest to the Y(+) direction side. Here, the point where the tangent line LT is tangent to the ultrasonic transducer 50 is defined as a tangent point P1 (forming a first intersection), and the point where the tangent line LT is tangent to the step surface 85 is defined as a tangent point P2.

[0052] The effective angle θ1 of the ultrasonic transducer 50 is an angle that indicates the irradiation range R1 of the ultrasonic waves emitted from the ultrasonic transducer 50 when the distal end rigid portion 34 is viewed from the X-direction side. Also, the dashed dotted line R1a in Fig. 6 indicates the boundary of the range of 1 / 3 (θ2 = 1 / 3 × θ1) from the base end side [Z(-) direction side] of the effective angle θ1.

[0053] 6, when the tip rigid portion 34 is viewed from the X direction, when the tip rigid portion 34 is brought into contact with the bronchial wall surface, contact points P1 and P2 come into contact with the bronchial wall surface, as indicated by the tangent line LT. In this case, the region of the tip rigid portion 34 between contact points P1 and P2 is an area that is difficult to contact with the bronchial wall surface, and conversely, the area distal to contact point P1 is an area that is easy to contact with the bronchial wall surface. Therefore, the area distal to contact point P1 of the base end of the ultrasonic transducer 50 is easy to contact with the bronchial wall surface, and conversely, the area proximal to contact point P1 is difficult to contact with the bronchial wall surface.

[0054] Therefore, in this embodiment, the shape of the tip rigid portion 34 is adjusted so that the contact point P1 is included in the range of 1 / 3 of the effective angle θ1 on the proximal side (the range of angle θ2 in the figure). This adjustment of the shape of the tip rigid portion 34 includes adjustment of the shape, attachment position, and posture of the ultrasonic transducer 50, and adjustment of the shape, formation position, and inclination angle of the step surface 85. It is more preferable that the contact point P1 be included in the range of 1 / 4 of the effective angle θ1 on the proximal side.

[0055] By adjusting the shape of the tip rigid portion 34 in this way, when the tip rigid portion 34 is brought into contact with the bronchial wall surface and when the tip rigid portion 34 is viewed from the X-direction side, the region of the base end of the ultrasonic transducer 50 between the dashed dotted line R1a and the contact point P1 can be reliably brought into contact with the bronchial wall surface (see FIG. 6). That is, a portion of the base end of the ultrasonic transducer 50 can be reliably brought into contact with the bronchial wall surface. As a result, the contact area of ​​the base end of the ultrasonic transducer 50 with the bronchial wall surface can be increased.

[0056] Furthermore, by adjusting the shape of the tip rigid portion 34 so that the position of the contact point P1 is shifted further toward the base end [Z(-) direction], the contact area of ​​the base end of the ultrasonic transducer 50 with the bronchial wall surface can be further increased.

[0057] As described above, by adjusting the shape of the tip rigid portion 34 so that the contact point P1 is within the range of 1 / 3 of the base end side of the effective angle θ1 of the ultrasonic transducer 50 when the tip rigid portion 34 is viewed from the X direction side, it is possible to reliably increase the contact area of ​​the base end of the ultrasonic transducer 50 with the bronchial wall surface. This ensures that the base end of the ultrasonic transducer 50 can reliably depict ultrasonic images of lymph nodes.

[0058] Next, we will explain modified examples of the tip rigid portion 34. In the tip rigid portion 34 of the above embodiment, the ultrasonic transducer 50, the outlet 52, and the stepped surface 85 (observation window 40a) are arranged from the tip side toward the base end, making it possible to observe with the observation optical system 40 the puncture of the lymph node from the bronchial wall surface by the puncture needle 100.

[0059] In contrast, the tip rigid section 34 of the modified example specifically defines conditions for ensuring that the puncture of the lymph node can be reliably observed with the observation optical system 40. The tip rigid section 34 of the modified example has basically the same configuration as the tip rigid section 34 of the above embodiment, and therefore, the same reference numerals are used to designate components that are the same in function or configuration as those of the above embodiment, and a description thereof will be omitted, and a description of the same effects as those of the above embodiment will also be omitted.

[0060] 7 is a cross-sectional view of a modified distal end rigid portion 34. As shown in FIG. 7, the intra-block conduit 74 has a shape that is bent in two stages when the distal end rigid portion 34 is viewed from the X direction side. Specifically, the intra-block conduit 74 is composed of a first conduit 74a and a second conduit 74b. The first conduit 74a is connected to the outlet 52 within the channel block component 70. The second conduit 74b is provided on the proximal end side of the first conduit 74a. The distal end of the treatment instrument insertion channel 23 is connected to the second conduit 74b.

[0061] When the distal end rigid portion 34 is viewed from the X direction side, an intersection P3 (forming the second intersection) between the tangent line LT and the center line L2A of the first conduit 74a is located at a position closer to the base end of the distal end rigid portion 34 than the contact point P1, more preferably within the range W between the ultrasonic transducer 50 and the observation window 40a. Note that if the outlet 52 opens closer to the base end of the distal end rigid portion 34 than the step surface 85 (observation window 40a), the intersection P3 will be located closer to the base end of the distal end rigid portion 34 than the contact point P1.

[0062] Intersection P3 corresponds to the position where the puncture needle 100, led out from the outlet 52, starts to puncture the lymph node from the bronchial wall when the ultrasonic transducer 50 is in contact with the bronchial wall. By positioning intersection P3 within range W, i.e., in front of the observation window 40a, the puncture of the lymph node from the bronchial wall by the puncture needle 100 can be reliably observed by the observation optical system 40.

[0063] Fig. 8 is a perspective view schematically showing the main parts of the bending section 32 of the endoscope 1 shown in Fig. 1. The bending section 32 includes a plurality of movable members 320 arranged in the Z direction, a base-end connecting member 35 connecting the most proximal (Z(-) direction) of the plurality of movable members 320 to the flexible section 30, a tip-end connecting member 33 connecting the most distal (Z(+) direction) of the plurality of movable members 320 to the tip-end rigid section 34, and two wires W inserted through the movable members 320, the base-end connecting member 35, and the tip-end connecting member 33. Although not shown, the plurality of movable members 320 are covered with a covering member, and an outer cover of the insertion section 12 is provided around the outer periphery of the movable members 320.

[0064] The bending section 32 includes a first region 321 and a second region 322 between the first region 321 and the distal rigid section 34. The first region 321 and the second region 322 are configured to be bendable with different radii of curvature. Specifically, the first region 321 is configured to be bendable with a first radius of curvature, and the second region 322 is configured to be bendable with a second radius of curvature that is smaller than the first radius of curvature. In other words, the bending section 32 is configured to bend slightly on its proximal end side and bend more on its distal end side than on the proximal end side.

[0065] 8, a total of 19 movable members 320 are provided. The first region 321 is configured to include 12 of the 19 movable members 320, which are arranged from the proximal connecting member 35 side. The second region 322 is configured to include 7 of the 19 movable members 320, which are arranged from the distal connecting member 33 side.

[0066] Each of the multiple movable members 320 is composed of a cylindrical member with an axis extending in the Z direction. The multiple movable members 320 include a first movable member 32A and a second movable member 32B whose width in the Z direction is smaller than that of the first movable member 32A. Of the 19 movable members 320, the first 10 movable members 320 counting from the base-end connecting member 35 side are first movable members 32A, and the 11th and subsequent movable members 320 counting from the base-end connecting member 35 side are second movable members 32B.

[0067] The first region 321 is configured to include ten first movable members 32A and two second movable members 32B. The second region 322 is configured to include seven second movable members 32B. The first movable member 32A located closest to the base end of the first region 321 is rotatably connected to a cylindrical base end connecting member 35. The second movable member 32B located closest to the tip end of the second region 322 is rotatably connected to a cylindrical tip end connecting member 33.

[0068] The two wires W are each connected to the angle lever 16 through the flexible section 30. The movable members 320, the base-side connecting member 35, and the tip-side connecting member 33 are made of, for example, metal or resin. The tip of each wire W is fixed to the tip-side connecting member 33.

[0069] Fig. 9 is an enlarged perspective view of the first movable member 32A shown in Fig. 8. Fig. 10 is an enlarged perspective view of the second movable member 32B shown in Fig. 8.

[0070] An end face 329 on the Z(+) direction side and an end face 329 on the Z(-) direction side of the first movable member 32A are each flat surfaces perpendicular to the Z direction.

[0071] The first movable member 32A is provided at one end in the X direction with a connecting piece 325 that protrudes in the Z(+) direction from an end face 329 on the Z(+) direction side, and at the other end of the first movable member 32A with a connecting piece 326 that protrudes in the Z(-) direction from an end face 329 on the Z(-) direction side. The connecting pieces 325 and 326 are plate-shaped with a thickness in the X direction. The connecting pieces 325 and 326 each have a connecting hole that penetrates in the X direction.

[0072] The first movable member 32A is provided at its other end in the X direction with a connecting piece 327 that protrudes in the Z(+) direction from an end face 329 on the Z(+) direction side, and at its other end with a connecting piece 328 that protrudes in the Z(-) direction from an end face 329 on the Z(-) direction side. The connecting pieces 327 and 328 are plate-shaped with a thickness in the X direction. Each of the connecting pieces 327 and 328 is provided with a connecting hole that penetrates in the X direction.

[0073] A pair of wire guides 324, through which two wires W are inserted, are provided on the inner circumferential surface of the first movable member 32A, facing each other in the Y direction between one end and the other end in the X direction.

[0074] As shown in FIG. 10, the second movable member 32B has the same configuration as the first movable member 32A, except that the width in the Z direction (the distance between the end face 329 on the Z(+) direction side and the end face 329 on the Z(-) direction side) is smaller than that of the first movable member 32A.

[0075] As shown in FIG. 8 , the connecting piece 325 of each movable member 320, except for the two closest to the base end and the two closest to the tip end, is rotatably connected to the connecting piece 326 of the adjacent movable member 320 on the tip end side by a connecting member 323 such as a rivet. The connecting piece 326 of each movable member 320 is rotatably connected to the connecting piece 325 of the adjacent movable member 320 on the base end side by a connecting member such as a rivet. The connecting piece 327 of each movable member 320 is rotatably connected to the connecting piece 328 of the adjacent movable member 320 on the tip end side by a connecting member such as a rivet. The connecting piece 328 of each movable member 320 is rotatably connected to the connecting piece 327 of the adjacent movable member 320 on the base end side by a connecting member such as a rivet.

[0076] Of all the movable members 320, the movable member 320 located closest to the base end is rotatably connected to the base end connecting member 35 by connecting members 323 such as rivets at connecting pieces 326 and 328. Of all the movable members 320, the movable member 320 located closest to the tip end is rotatably connected to the tip end connecting member 33 by connecting members 323 such as rivets at connecting pieces 325 and 327.

[0077] In the endoscope 1, the wire W inserted through the wire guide 324 on the Y(+) direction side of the wire guides 324 of the movable member 320 is pulled by rotating the angle lever 16 in the A1 direction, whereby the bending section 32 is bent in the Y(+) direction (the A2 direction in FIG. 1). The wire W inserted through the wire guide 324 on the Y(-) direction side of the wire guides 324 of the movable member 320 is pulled by rotating the angle lever 16 in the -A1 direction, whereby the bending section 32 is bent in the Y(-) direction (the -A2 direction in FIG. 1).

[0078] FIG. 11 is a schematic diagram showing the curved portion 32 shown in FIG. 8 as viewed in direction X. As shown in FIG. 11, a gap is provided between the end faces 329 of two adjacent first movable members 32A, and the length of this gap in the Z direction is distance L1. A gap is provided between the end faces 329 of two adjacent second movable members 32B, and the length of this gap in the Z direction is distance L2. A gap is provided between the end faces 329 of the tenth first movable member 32A counting from the base end and the adjacent second movable member 32B, and the length of this gap in the Z direction is distance L3. The distance L4 in the Z direction between the connecting members 323 that rotatably connect adjacent movable members 320 is uniform throughout.

[0079] Since the gap L4 is uniform, the distance L2 is greater than the distance L1 due to the difference in the width in the Z direction between the first movable member 32A and the second movable member 32B. The distance L3 is half the distance L2 plus half the distance L1.

[0080] The length in the Z direction of the gap between the base-end connecting member 35 and the adjacent first movable member 32A is a distance L7. Distance L7 is preferably greater than distance L1. Furthermore, distance L7 is preferably smaller than distance L2. Distance L7 is preferably equal to or less than distance L3, for example. This makes it easy to increase the bending angle when the first region 321 is bent to the maximum while suppressing the length of the first region 321 in the Z direction.

[0081] 11, the portion from the distal end face of the proximal connecting member 35 to the proximal end face 329 of the seventh second movable member 32B, counting from the distal connecting member 33 side, constitutes the first region 321. Furthermore, the portion from the proximal end face of the distal connecting member 33 to the proximal end face 329 of the seventh second movable member 32B, counting from the distal connecting member 33 side, constitutes the second region 322. It is preferable that the length L5 of the first region 321 in the Z direction be equal to or greater than the length L6 of the second region 322 in the Z direction.

[0082] When the rotation angle of the angle lever 16 is 0°, as shown in FIG. 11, the axis 35J of the base-end connecting member 35 and the axis 33J of the tip-end connecting member 33 are aligned in a straight line, and the angle between the axis 35J and the axis 33J is 0°. The axis 33J coincides with the axis of the tip-end rigid section 34. The axis 35J coincides with the axis of the flexible section 30. When the angle lever 16 is rotated, the axis 33J of the tip-end connecting member 33 tilts relative to the axis 35J of the base-end connecting member 35, and the angle between the axis 35J and the axis 33J increases. The angle between the axis 35J and the axis 33J is defined as the bending angle of the bending section 32. In the state shown in FIG. 11, the bending angle is 0°.

[0083] The bending angle of the bending section 32 when the angle lever 16 is rotated to the maximum in the A1 direction (when the rotation angle is 45°) (the second upper limit of the bending angle when rotated in the A1 direction) is also referred to as the maximum bending angle in the A2 direction. In order to ensure that the surface of the tip rigid section 34 on the ultrasonic transducer 50 side can easily and appropriately contact the desired site in the bronchus, the maximum bending angle in the A2 direction is preferably in the range of 165° to 195°, and more preferably 180°.

[0084] The bending angle of the bending section 32 when the angle lever 16 is rotated to the maximum in the -A1 direction (the third upper limit of the bending angle when rotated in the -A1 direction) is also referred to as the maximum bending angle in the -A2 direction. Taking into consideration the ability to follow the shape of the bronchi, operability, and optimization of manufacturing costs, the maximum bending angle in the -A2 direction is preferably smaller than the maximum bending angle in the A2 direction. The maximum bending angle in the -A2 direction is preferably, for example, in the range of 75° to 115°, and more preferably 90°.

[0085] Fig. 12 is a schematic diagram for explaining the bending state of the bending portion 32 when the angle lever 16 is rotated in the A1 direction from the state shown in Fig. 11. The Y direction and Z direction shown in Fig. 12 are shown as directions in a state in which the bending portion 32 extends linearly in the vertical direction in the figure (a state in which the bending portion 32 is not bent).

[0086] When the angle lever 16 is rotated in the A1 direction within a first range (a range of a rotation angle greater than 0° and equal to or less than 25°), only the first region 321 of the first region 321 and the second region 322 is bent in the Y(+) direction as shown in Fig. 12. Meanwhile, the second region 322 maintains a state of extending along the axis 33J (synonymous with the axis of the distal end rigid portion 34).

[0087] 12 shows a state in which the angle lever 16 is rotated within the first range to reach the maximum bending angle (angle θ3) (a state in which the angle lever 16 has a rotation angle of 25°). Until the angle lever 16 reaches a rotation angle of 25°, the gap between the base-end connecting member 35 and the adjacent movable member 320, the gap between the movable members 320 included in the first region 321, and the gap between the most distal movable member 320 in the first region 321 and the adjacent movable member 320 on that distal side gradually narrow, and the first region 321 bends in the Y(+) direction.

[0088] Meanwhile, while the first region 321 is curved, the gaps between the movable members 320 included in the second region 322 and the gap between the tip side connecting member 33 and the adjacent movable member 320 are maintained in the state shown in Fig. 11. The angle θ3 shown in Fig. 12 is 90°, for example. In this way, the orientation of the tip rigid section 34 can be changed while the second region 322 is kept straight until the bending angle changes from 0° to 90°.

[0089] Fig. 13 is a schematic diagram illustrating a state in which an endoscope 1 is inserted into a bronchus and used. Fig. 13 shows a trachea 101 of a subject, lungs 103 of the subject, a pair of main bronchi 102 branching downward from the trachea 101, and a bronchus 105 branching upward from the main bronchus 102 via an upper lobe bronchus 104. In clinical practice, treatment may be performed on an ipsilateral hilar lymph node 106 located above the main bronchus 102 at the back.

[0090] As described above, the endoscope 1 can bend the first region 321 with a large radius of curvature while maintaining the second region 322 in a straight line. As shown in Fig. 13, by bending the first region 321, the tip rigid section 34 can be smoothly inserted along a gently curved and relatively long path from the trachea 101 to the main bronchus 102.

[0091] 13, if the first region 321 is further bent in direction B in the figure (corresponding to the Y(+) direction), the tip rigid portion 34 moves in direction C in the figure. Because the second region 322 is maintained in a straight line, the contact point P1 (see FIG. 5) of the tip rigid portion 34 can move without significantly changing its relative position with respect to the ipsilateral hilar lymph node 106. This makes it easy to bring the vicinity of the contact point P1 of the tip rigid portion 34 into contact with the ipsilateral hilar lymph node 106.

[0092] For example, assume a configuration in which the proximal end of the bending section 32 remains straight while only the distal end bends, as in the prior art. In this configuration, it becomes difficult to insert the distal rigid section 34 to the position of the ipsilateral hilar lymph node 106 deep inside the main bronchus 102.

[0093] Also, assume that the bending portion 32 is configured to bend as a whole in response to the rotation of the angle lever 16. In this configuration, there is a possibility that the ultrasonic transducer 50 will be directed toward the base end during the process of inserting the distal rigid portion 34 deep into the main bronchus 102, making it difficult to position the vicinity of the contact point P1 facing the ipsilateral hilar lymph node 106.

[0094] According to the endoscope 1 of this embodiment, the vicinity of the contact point P1 can be easily positioned to face the ipsilateral hilar lymph node 106 located deep and above the main bronchus 102. Therefore, when treating the ipsilateral hilar lymph node 106 while observing it with an ultrasound image, the treatment can be performed with high accuracy.

[0095] In order to bring the ultrasonic transducer 50 into contact with the wall surface of the main bronchus 102 near the ipsilateral hilar lymph node 106, the bending angle of the bending portion 32 when the second region 322 is held linearly may be approximately 50° to 65°. In other words, the first upper limit value (angle θ3 shown in FIG. 12) of the bending angle of the bending portion 32 when the second region 322 is held linearly (when the angle lever 16 is rotated within the first range) may be set to at least a range of 50° to 65°.

[0096] However, when a procedure such as a biopsy is performed on the ipsilateral hilar lymph node 106, the puncture needle 100 is inserted into the ipsilateral hilar lymph node 106 with the ultrasonic transducer 50 in contact with the wall surface of the main bronchus 102. When the puncture needle 100 is inserted, the first region 321 may be pushed back by about 30° in the direction opposite to direction B in FIG. 13 , and in this case, the ultrasonic transducer 50 may be separated from the wall surface of the main bronchus 102.

[0097] Therefore, it is preferable to set the first upper limit value to be greater than the range of 50° to 65°. In this way, the puncture needle 100 can be inserted while further bending the first region 321 in direction B in the state shown in Fig. 13 (for example, a state where the bending angle is 60°). In this way, the puncture needle 100 can be inserted into the ipsilateral hilar lymph node 106 while preventing the ultrasonic transducer 50 from separating from the wall surface of the main bronchus 102.

[0098] From the viewpoint of properly observing and treating the ipsilateral hilar lymph node 106, the above-mentioned first upper limit value is preferably 50° or more and 100° or less, more preferably 60° or more and 95° or less, and even more preferably 90°.

[0099] Fig. 14 is a schematic diagram for explaining the bending state of the bending portion 32 when the rotation angle of the angle lever 16 is increased from the state shown in Fig. 12. When the angle lever 16 is rotated in the A1 direction through a second range (a range of a rotation angle greater than 25° and equal to or less than 45°) that exceeds the first range, only the second region 322 of the first region 321 and the second region 322 is bent, as shown in Fig. 14. Meanwhile, the first region 321 maintains the bending state shown in Fig. 12 (the bending state at a rotation angle of 25° (the rotation angle at the end of the first range on the second range side)).

[0100] FIG. 14 shows a state in which the angle lever 16 is rotated within the second range to reach the maximum bending angle (180° in the illustrated example) (when the angle lever 16 is rotated at a 45° angle). Until the angle lever 16 reaches a rotation angle of 45° beyond 25°, the gaps between the five movable members 320 included in the second region 322, excluding the two distal-side movable members 320 (denoted by reference numeral 32Bb in FIG. 14), gradually decrease. As a result, a portion 322A of the second region 322 (a portion proximal to the two movable members 32Bb) bends with a smaller radius of curvature than the first region 321. As shown in FIG. 14, when the angle lever 16 is rotated at a 45° angle, the axes of the two movable members 32Bb coincide with the axis 33J of the distal-side connecting member 33. That is, even when the angle lever 16 is rotated to the maximum in the A1 direction, the other portion 322B of the second region 322, excluding the portion 322A, maintains a straight shape.

[0101] In this way, the other portion 322B of the second region 322 is configured so that it cannot be bent by rotating the angle lever 16. In this embodiment, the rotational range of the angle lever 16 is restricted to prevent the other portion 322B from bending. However, when an external force is applied to the other portion 322B, it can be bent in both the Y(+) direction and the Y(-) direction with the same radius of curvature as the part 322A. Because the other portion 322B is linear, the puncture needle 100 can be smoothly led out from the lead-out port 52. Note that the other portion 322B is not essential to the second region 322 and can be omitted.

[0102] 15 is a schematic diagram for explaining a state in which the endoscope 1 is inserted into a bronchus and used. In clinical practice, there are cases in which observation and treatment are performed around a bronchus 105 branching upward from an upper lobe bronchus 104.

[0103] When inserting the tip rigid section 34 into the bronchus 105, the tip rigid section 34 can be smoothly inserted along a gently curved and relatively long path from the trachea 101 to the upper lobe bronchi 104 while bending the first region 321. Furthermore, because the second region 322 can be curved with a small radius of curvature from a state in which the first region 321 is curved to the maximum extent, the tip rigid section 34 can be easily inserted deep into the bronchi 105, which branch off at an acute angle from the path from the trachea 101 to the upper lobe bronchi 104, as shown in Fig. 15 .

[0104] Even when the distal end rigid portion 34 is inserted into a narrow bronchus, the other portion 322B of the second region 322 is passively bendable, so that the insertion can be carried out smoothly.

[0105] Furthermore, when the second region 322 is bent from a state in which the first region 321 is maximally bent, the bent state of the first region 321 is maintained. Therefore, with the first region 321 stabilized by being brought into contact with the wall surface of the main bronchus 102, for example, the second region 322 can be bent to change the orientation of the tip rigid portion 34.

[0106] In this way, in order to enable the tip rigid portion 34 to be smoothly inserted along the path from the trachea 101 through the main bronchus 102 to the upper lobe bronchus 104, and from the upper lobe bronchus 104 to the upper bronchus 105, the relationship between the length L5 of the first region 321 and the length L6 of the second region 322 shown in Figure 11 is important.

[0107] If length L6 is greater than length L5, it will be difficult to maneuver the rigid tip portion 34 in the narrow space beyond the upper lobe lance 104. In contrast, by making length L6 and length L5 the same, it will be possible to insert the rigid tip portion 34 deep into the bronchus 105 while making it easier to maneuver the rigid tip portion 34 in the narrow space beyond the upper lobe lance 104.

[0108] Furthermore, if length L6 is set to be shorter than length L5, it becomes easier to handle the tip rigid portion 34 in the narrow space beyond the upper lobe bronchus 104. However, if length L6 is set too short, it becomes difficult to insert the tip rigid portion 34 deep into the bronchus 105. Furthermore, if length L6 is set too short, it becomes difficult to increase the amount of curvature of the second region 322.

[0109] 13, when the tip rigid portion 34 is to approach the ipsilateral hilar lymph node 106, if the length L6 is made too large, it becomes difficult to move the tip rigid portion 34 deep into the main bronchus 102. If the length L6 is made too small, for example, with the base end of the first region 321 inserted into the main bronchus 102, the tip rigid portion 34 needs to be curved in a direction that brings it closer to the ipsilateral hilar lymph node 106. As shown in FIG. 13, with the base end of the first region 321 supported and stabilized by the wall surface of the trachea 101, it becomes difficult to curve the first region 321 and bring the tip rigid portion 34 closer to the ipsilateral hilar lymph node 106.

[0110] Taking the above circumstances into consideration, and as a result of repeated verification, it was found that by setting the length L6 to be between 0.5 and 1.0 times the length L5, it is possible to improve the operability and treatment accuracy when approaching the ipsilateral hilar lymph node 106 with the tip rigid portion 34, and also to improve the operability of inserting the tip rigid portion 34 into the bronchus 105.

[0111] As an example, it is preferable that the length L5 is 34.5 mm, the length L6 is 19.6 mm, the distance L1 is 0.2 mm, the distance L2 is 0.95 mm, the distance L3 is 0.575 mm, the spacing L4 is 2.8 mm, the distance L7 is 0.5 mm, the outer diameter of the movable member 320 is 6.3 mm, and the curvature R of the second region 322 is R6.

[0112] As described above, when examining or treating the bronchi, it is preferable to set the second upper limit of the bending angle of the bending section 32 when the angle lever 16 is operated within the second range to 165° or more and 195° or less. This allows the tip rigid section 34 to appropriately approach the bronchi that branch off from the upper lobe bronchus 104 at an acute angle, as described above.

[0113] Fig. 16 is a schematic diagram for explaining the bending state of the bending portion 32 when the angle lever 16 is rotated in the -A1 direction from the state shown in Fig. 11. The Y direction and Z direction shown in Fig. 16 are shown as directions in a state in which the bending portion 32 extends linearly in the vertical direction in the figure (a state in which the bending portion 32 is not bent).

[0114] When the angle lever 16 is rotated in the -A1 direction within a third range (a range of a rotation angle greater than 0° and equal to or less than 25°), only the first region 321 of the first region 321 and the second region 322 is bent in the Y(-) direction as shown in Fig. 16. Meanwhile, the second region 322 maintains a state of extending along the axis 33J (synonymous with the axis of the distal end rigid portion 34).

[0115] The bending state of the bending portion 32 when the angle lever 16 is rotated in the -A1 direction through the third range is the same as when the angle lever 16 is rotated in the A1 direction through the first range, except that the bending direction of the bending portion 32 is the Y (-) direction. Figure 16 shows the state in which the angle lever 16 is rotated in the third range and the bending angle is at its maximum (angle θ4). The angle θ4 is, for example, 90°. The angle θ4 is preferably the same as the angle θ3, but may be smaller than the angle θ3.

[0116] In this embodiment, the angle lever 16 can only rotate within a third range in the -A1 direction. That is, the third upper limit (angle θ4) of the bending angle of the bending portion 32 in the Y(-) direction when the angle lever 16 is rotated is smaller than the second upper limit.

[0117] As shown in Figure 17, assuming that the tip rigid section 34 is inserted into a bronchus below the upper lobe bronchus 104, the maximum bending angle in the Y(-) direction can be smaller than the maximum bending angle in the Y(+) direction. In this way, by configuring the tip rigid section 34 to bend just enough in the Y(-) direction, efficient operation according to the area to be observed is possible. In particular, when the tip rigid section 34 is inserted into a narrow area such as the bronchus, it is preferable to bend it only as much as necessary, and from this perspective, it is also preferable to make the maximum bending angle in the Y(-) direction smaller than the maximum bending angle in the Y(+) direction.

[0118] As explained above, this specification describes at least the following:

[0119] (1) an insertion section including a distal end portion including an ultrasound transducer array and a curved portion provided on a proximal end side of the distal end portion; a bending operation unit capable of bending the bending portion, the curved portion includes a first region and a second region between the first region and the tip portion; the first region is curved toward a surface of the distal end portion on which the ultrasonic transducer array is provided when the bending operation unit is operated within a first range, The second region is maintained in a state of extending along the axis of the tip portion when the bending operation section is operated within the first range.

[0120] (2) The endoscope according to (1), The endoscope has a distal end portion having an outlet for a treatment tool on the bending portion side of the ultrasonic transducer array.

[0121] (3) The endoscope according to (2), The endoscope has a first upper limit value of the bending angle of the bending portion when the bending operation portion is operated within the first range, which is equal to or greater than 50° and equal to or less than 100°.

[0122] (4) The endoscope according to (3), The first upper limit value is equal to or greater than 60° and equal to or less than 95°.

[0123] (5) An endoscope according to any one of (1) to (4), An endoscope in which at least a portion of the second region bends toward the surface of the tip on which the ultrasonic transducer array is provided when the bending operation section is operated within a second range that exceeds the first range.

[0124] (6) (5) The endoscope according to the present invention, The first region is an endoscope that maintains a bent state when the bending operation unit is operated to the end of the first range on the second range side when the bending operation unit is operated in the second range.

[0125] (7) (6) The endoscope according to (6), The endoscope is configured so that the tip end portion of the second region cannot be bent by the bending operation portion.

[0126] (8) (7) The endoscope according to (7), The end of the second region on the tip side is configured to be bendable by an external force.

[0127] (9) The endoscope according to any one of (5) to (8), The endoscope has a second upper limit value of the bending angle of the bending portion when the bending operation portion is operated within the second range, which is equal to or greater than 165° and equal to or less than 195°.

[0128] (10) (9) The endoscope according to (9), the bending portion is further bendable to a side opposite to a surface of the distal end portion on which the ultrasonic transducer array is provided, an endoscope wherein a third upper limit value of the bending angle to the opposite side when the bending operation section is operated is smaller than the second upper limit value;

[0129] (11) The endoscope according to (10), The third upper limit value is equal to or less than the upper limit value of the bending angle of the bending portion when the bending operation portion is operated within the first range.

[0130] (12) An endoscope according to any one of (1) to (11), an endoscope in which the length of the second region in the longitudinal axis direction of the insertion portion is equal to or less than the length of the first region in the longitudinal axis direction;

[0131] (13) The endoscope according to (12), An endoscope in which the length of the second region in the longitudinal axis direction of the insertion section is 0.5 times or more the length of the first region in the longitudinal axis direction.

[0132] (14) The endoscope according to any one of (1) to (13), The outer peripheral surface of the tip portion is a first surface provided on a proximal end side of the ultrasound transducer array and extending along a longitudinal axis of the insertion portion; a second surface provided on a base end side of the first surface, the second surface being along the longitudinal axis and positioned on one side of the first surface in a first direction perpendicular to the longitudinal axis; a step surface connecting a base end side of the first surface and a tip end side of the second surface; Including, An ultrasonic endoscope in which, when a direction perpendicular to both the longitudinal axis and the first direction is defined as a second direction, an angle indicating the irradiation range of ultrasound emitted from the ultrasonic transducer array when the tip is viewed from the second direction side is defined as an effective angle, and the intersection of a tangent line that is tangent to the ultrasonic transducer array and to the step surface at a position closest to the one direction side with the ultrasonic transducer array is defined as a first intersection, the first intersection is included within a range of the base end side 1 / 3 of the effective angle.

[0133] (15) The endoscope according to (14), an outlet provided on an outer peripheral surface of the distal end portion, the outlet opening toward the one side and through which a treatment tool is led out; a conduit connected to the outlet in the distal end portion and through which the treatment tool is inserted; an observation window for an observation optical system provided on the step surface; Equipped with When the tip portion is viewed from the second direction side, a second intersection point, which is the intersection point between the center line of the tip portion of the conduit connected to the outlet and the tangent line, is located closer to the base end of the tip portion than the first intersection point.

[0134] (16) The endoscope according to (15), An endoscope in which the second intersection is located between the ultrasound transducer array and the step surface. [Explanation of symbols]

[0135] 1. Ultrasound endoscope 10 Control section 12 Insertion section 14 Universal Code 16 Angle lever 22 Suction button 23 Treatment tool insertion channel 24 Treatment tool introduction port 30 Soft part 32 Curved section 32A First Movable Member 32B, 32Bb Second movable member 320 Movable parts 33 Tip connecting member 33J,35J axis 34 Tip rigid part 34a Ultrasonic mounting part 34b Outlet forming part 34c Main body 35 Base end connecting member 38 Longitudinal axis 40 Observation optical system 40a Observation window 40b lens system 40c image sensor 44 Illumination optical system 44a Lighting window 50 Ultrasonic Transducer 52 Outlet 54,56 Signal cable 58 Light Guide 60 Ultrasonic Block Parts 62 Optical block component mounting section 64 Locking part 65 Mounting opening 66 Guide part 70 Channel Block Parts 71 Aperture forming surface 72 flange surface 73 Locked part 74 Block internal pipeline 74a 1st pipeline 74b 2nd pipeline 80 Optical block parts 81 Channel block part mounting section 81a plane 81b Support surface 82 Optical system storage section 84 Convex 85 Step surface 90 Continuous Plane 100 puncture needle 101 Trachea 102 Main bronchus 103 Lungs 104 Upper lobe 105 Bronchi 106 Ipsilateral hilar lymph nodes 321 1st area 322 Second area 322A part 322B Other parts 323 Connecting members 324 Wire Guide 325,326,327,328 Connecting piece 329 End face P1, P2 contacts P3 intersection θ1 effective angle R1 Irradiation Range L2A center line L1,L2,L3,L7 distance L4 interval L5, L6 length

Claims

1. an insertion section including a distal end portion including an ultrasound transducer array and a curved portion provided on a proximal end side of the distal end portion; a bending operation unit capable of bending the bending portion, the curved portion includes a first region and a second region between the first region and the tip portion, the first region is curved toward a surface of the distal end portion on which the ultrasonic transducer array is provided when the bending operation unit is operated within a first range, The second region is maintained in a state of extending along the axis of the tip portion when the bending operation section is operated within the first range.

2. The endoscope according to claim 1, The endoscope has a distal end portion having an outlet for a treatment tool on the bending portion side of the ultrasonic transducer array.

3. The endoscope according to claim 2, An endoscope, wherein a first upper limit value of the bending angle of the bending portion when the bending operation portion is operated within the first range is 50° or more and 100° or less.

4. The endoscope according to claim 3, An endoscope wherein the first upper limit value is equal to or greater than 60° and equal to or less than 95°.

5. The endoscope according to any one of claims 1 to 4, An endoscope in which at least a portion of the second region bends toward the surface of the tip on which the ultrasonic transducer array is provided when the bending operation unit is operated within a second range that exceeds the first range.

6. The endoscope according to claim 5, The first region is an endoscope that maintains a bent state when the bending operation unit is operated to the end of the first range on the second range side when the bending operation unit is operated within the second range.

7. The endoscope according to claim 6, An endoscope in which the end portion on the tip side of the second region is configured so that it cannot be bent by the bending operation portion.

8. The endoscope according to claim 7, The end of the second region on the tip side is configured to be bendable by an external force.

9. The endoscope according to claim 8, An endoscope wherein a second upper limit value of the bending angle of the bending portion when the bending operation portion is operated within the second range is 165° or more and 195° or less.

10. The endoscope according to claim 9, the bending portion is further bendable to a side opposite to a surface of the distal end portion on which the ultrasonic transducer array is provided, an endoscope in which a third upper limit value of the bending angle to the opposite side when the bending operation section is operated is smaller than the second upper limit value;

11. The endoscope according to claim 10, The third upper limit value is equal to or less than the upper limit value of the bending angle of the bending portion when the bending operation portion is operated within the first range.

12. The endoscope according to claim 11, An endoscope, wherein the length of the second region in the longitudinal axis direction of the insertion portion is equal to or less than the length of the first region in the longitudinal axis direction.

13. The endoscope according to claim 12, An endoscope, wherein the length of the second region in the longitudinal axis direction of the insertion portion is 0.5 times or more the length of the first region in the longitudinal axis direction.

14. The endoscope according to claim 13, The outer peripheral surface of the tip portion is a first surface provided on a proximal end side of the ultrasound transducer array and extending along a longitudinal axis of the insertion portion; a second surface provided on a base end side of the first surface, the second surface being along the longitudinal axis and positioned on one side of the first surface in a first direction perpendicular to the longitudinal axis; a step surface connecting a base end side of the first surface and a tip end side of the second surface; Including, an ultrasonic endoscope in which, when a direction perpendicular to both the longitudinal axis and the first direction is defined as a second direction, an angle indicating the irradiation range of ultrasound emitted from the ultrasonic transducer array when the tip is viewed from the second direction side is defined as an effective angle, and a first intersection point is defined as an intersection point between a tangent line that is tangent to the ultrasonic transducer array and to the step surface at a position closest to the one direction side and the ultrasonic transducer array, the first intersection point is included within a range of 1 / 3 of the base end side of the effective angle.

15. The endoscope according to claim 14, an outlet provided on an outer peripheral surface of the distal end portion, the outlet opening toward the one side and through which a treatment tool is led out; a conduit connected to the outlet in the distal end portion and through which the treatment tool is inserted; an observation window for an observation optical system provided on the step surface; Equipped with When the tip portion is viewed from the second direction, a second intersection point, which is the intersection point between the center line of the tip portion of the duct connected to the outlet and the tangent line, is located closer to the base end of the tip portion than the first intersection point.

16. 16. The endoscope according to claim 15, An endoscope in which the second intersection is located between the ultrasound transducer array and the step surface.

Images