Ultrasound endoscope balloon

Abstract

To provide a balloon for an ultrasonic endoscope that can allow an ultrasonic vibrator surface of an ultrasonic transducer to swell most.SOLUTION: A balloon for an ultrasonic endoscope mounted so as to cover an external surface of an ultrasonic transducer provided in a distal end body on a distal side of an insertion part includes: a balloon body of a bottomed cylindrical shape having an opening provided at one end in a first direction corresponding to a longitudinal direction of the insertion part and attached to the distal end body, which covers a vibrator surface of the ultrasonic transducer, and can swell when an ultrasonic transmission medium is stored inside; and a swelling regulation part that can swell a vibrator surface region opposed to the vibrator surface of the ultrasonic transducer most by regulating a part of the balloon body when the ultrasonic transmission medium is stored inside the balloon body.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a balloon for an ultrasonic endoscope, and more particularly to a balloon attached to the tip of an insertion section of an ultrasonic endoscope. [Background technology]

[0002] Ultrasound endoscopes are used in the medical field. An ultrasound endoscope is an endoscope that has an imaging element and an ultrasound transducer integrally arranged at the tip of an insertion section that is inserted into a body cavity of a subject. The ultrasound transducer emits ultrasound toward an area to be observed within the body cavity, receives echo signals reflected from the area to be observed, and outputs electrical signals corresponding to the received echo signals to an ultrasound observation device. After various signal processing steps are performed in the ultrasound observation device, the signals are displayed on a monitor or the like as an ultrasound tomographic image.

[0003] Because ultrasonic waves and echo signals are significantly attenuated in air, an ultrasonic transmission medium such as water or oil must be placed between the ultrasonic transducer and the region to be observed. Therefore, a stretchable balloon is attached to the tip of the ultrasonic endoscope, and the balloon is inflated by injecting an ultrasonic transmission medium into it and then placed in contact with the region to be observed. This removes air from between the ultrasonic transducer and the region to be observed, preventing attenuation of the ultrasonic waves and echo signals.

[0004] Various balloons have been proposed for attachment to the distal end of the insertion section of an ultrasonic endoscope.

[0005] Patent Document 1 discloses providing a groove surrounding a transducer at the tip of an insertion section and attaching a balloon to the groove. Patent Document 2 discloses providing a restricting means for restricting the inflation of the balloon in the scanning axis direction on the ultrasonic transducer. Patent Document 3 discloses an ultrasonic diagnostic device having a flexible membrane attached to a probe body so as to form an enclosed space in front of an ultrasonic transmission / reception surface, and a fluid filled in the enclosed space. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-254942 [Patent Document 2] Japanese Patent Application Publication No. 08-131442 [Patent Document 3] Japanese Patent Application Publication No. 53-107190 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when a balloon is attached to a position covering the outer surface of an ultrasonic transducer, for example, when diagnosing or treating narrow passages such as the bronchi inside a body cavity using an ultrasonic bronchoscope, if the balloon containing the tip where the ultrasonic transducer is located expands into a spherical shape, the outer diameter of the balloon will increase, and there is a concern that the contact position of the transducer surface will not be stable.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a balloon for an ultrasonic endoscope that allows the ultrasonic vibrator surface of the ultrasonic transducer to expand to the maximum extent. [Means for solving the problem]

[0009] A first aspect of the present invention is a balloon for an ultrasonic endoscope that is attached so as to cover the outer surface of an ultrasonic transducer provided on a tip body on the tip side of an insertion section, and is a cylindrical balloon body with a bottom that has an opening provided at one end in a first direction corresponding to the longitudinal direction of the insertion section and attached to the tip body, and is equipped with: a balloon body that covers the transducer surface of the ultrasonic transducer and can be inflated by storing an ultrasonic transmission medium inside; and an inflation control part that restricts part of the balloon body when the ultrasonic transmission medium is stored inside the balloon body, thereby causing the transducer surface area facing the transducer surface of the ultrasonic transducer to bulge the most.

[0010] A second aspect of the present invention is a balloon for an ultrasonic endoscope, in which the balloon body has at least a two-layer structure including an inner part having an opening at one end and an outer part covering the inner part and attached to the opening side, and is provided with a storage part for storing an ultrasonic transmission medium between the inner part and the outer part, and the outer part has a transducer surface area.

[0011] A third aspect of the present invention provides a balloon for an ultrasonic endoscope, which includes an adhesive portion that bonds the inner portion and the outer portion together, and the adhesive portion functions as an expansion restricting portion.

[0012] In a fourth aspect of the present invention, in a balloon for an ultrasonic endoscope, the outer part has a thick-walled portion formed on the other end side opposite to one end in a first direction with a thickness greater than the thickness of the transducer surface region, and the thick-walled portion functions as an expansion control portion.

[0013] A fifth aspect of the present invention is a balloon for an ultrasonic endoscope, in which the outer part comprises thick portions formed on both sides of the transducer surface area in a second direction perpendicular to the first direction of the transducer surface area with a thickness greater than the thickness of the transducer surface area, and a transition portion formed between the thick portions and the transducer surface area, and the transition portion functions as an expansion control portion.

[0014] A sixth aspect of the present invention provides a balloon for an ultrasonic endoscope, which has adhesive regions between an inner part and an outer part on both sides of a transducer surface region in a second direction perpendicular to the first direction, and the adhesive regions function as expansion restricting portions.

[0015] A seventh aspect of the present invention is a balloon for an ultrasonic endoscope, wherein the balloon body has an area smaller than the distance between the upright walls provided on both sides of the ultrasonic transducer before the tip body is attached.

[0016] An eighth aspect of the present invention is a balloon for an ultrasonic endoscope, wherein the balloon body has a protrusion that protrudes toward the tip body and fits into a groove formed on the base end side of the ultrasonic transducer of the tip body.

[0017] A ninth aspect of the present invention provides a balloon for an ultrasonic endoscope, wherein the balloon body includes a locking portion that locks onto a step formed on the surface of the tip body opposite the ultrasonic transducer. [Effects of the Invention]

[0018] According to the balloon for ultrasonic endoscopes of the present invention, the ultrasonic vibrator surface of the ultrasonic transducer can be swollen to the maximum extent. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is an overall view of an ultrasonic endoscope (endoscope). [Figure 2] FIG. 2 is a perspective view of the tip body. [Figure 3] FIG. 3 is a cross-sectional view of the tip body. [Figure 4] FIG. 4 is a perspective view of the tip body. [Figure 5] FIG. 5 is a side view of the tip body. [Figure 6] FIG. 6 is a plan view of the tip body. [Figure 7] FIG. 7 is an exploded view of the balloon for an ultrasonic endoscope, omitting the tube. [Figure 8] FIG. 8 is a cross-sectional view of a balloon for an ultrasonic endoscope. [Figure 9] FIG. 9 is a cross-sectional view illustrating the flow of an ultrasonic wave transmission medium supplied to a balloon for an ultrasonic endoscope. [Figure 10] FIG. 10 is a cross-sectional view showing a state in which the transducer surface area of ​​the balloon for an ultrasonic endoscope is inflated. [Figure 11] FIG. 11 is a perspective view illustrating the attachment of the balloon for an ultrasonic endoscope, without the tube, to the distal end body. [Figure 12] FIG. 12 is a perspective view of the distal end body, to which the balloon for an ultrasonic endoscope is attached, cut along the XZ plane, without the tube. [Figure 13] FIG. 13 is a cross-sectional view of the distal end body with the ultrasonic endoscope balloon attached, cut along the YZ plane. [Figure 14] FIG. 14 is a perspective view of the balloon for an ultrasonic endoscope, without the tube, as viewed from the proximal end side. [Figure 15] FIG. 15 is a perspective view illustrating the attachment of a balloon for an ultrasonic endoscope to a distal end body in another embodiment in which the tube is omitted. DETAILED DESCRIPTION OF THE INVENTION

[0020] An ultrasonic endoscope to which a balloon for an ultrasonic endoscope according to the present invention is attached will now be described with reference to the accompanying drawings.

[0021] [Overall configuration of an ultrasound endoscope] Figure 1 is an overall view of an ultrasonic endoscope 1. As shown in Figure 1, the ultrasonic 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 a medical examination site). In this embodiment, a bronchial lymph node will be used as an example of the lesion.

[0022] The endoscope 1 is composed of an operation section 10 that is held by the practitioner 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, a light source device, and an ultrasound observation device (not shown) that constitute an endoscope system.

[0023] 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.

[0024] 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. 3) that passes through the insertion section 12.

[0025] The insertion section 12 extends from the tip of the operating section 10 and is formed in a long shape with a small diameter as a whole. The insertion section 12 is composed of, in order from the base end side to the tip end side, a flexible section 30, a bending section 32, and a tip section main body 34 which is the tip end.

[0026] 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.

[0027] The bending portion 32 is adapted to bend in the vertical direction (A2 direction) by rotating the angle lever 16 of the operating unit 10 in the A1 direction, and by bending the bending portion 32, the tip body 34 can be directed in the desired direction.

[0028] The tip body 34 will be described in detail using Figures 2 and 3 below, and is equipped with an observation optical system 40 and an illumination optical system 44 for capturing observation images inside the body, an ultrasonic transducer 50 for acquiring ultrasonic images, and a treatment tool outlet 52 (hereinafter referred to as outlet 52) ​​for guiding the treatment tool inserted from the treatment tool inlet 24.

[0029] The universal cord 14 contains signal cables 54, 56, and a light guide 58, the details of which are shown in FIG. 3, which will be described later. A connector is provided at one end (not shown) of the universal cord 14. This connector is connected to predetermined system components that constitute an endoscope system, such as a processor device, a light source device, and an ultrasound observation device. As a result, the system components supply the endoscope 1 with power, control signals, illumination light, and other signals necessary for operating the endoscope 1. Signals of observation images acquired by the observation optical system 40 and signals of ultrasound images acquired by the ultrasound transducer 50 are transmitted from the endoscope 1 to the system components. The signals transmitted to the system components are subjected to image processing, and the observation images and ultrasound images are displayed on a monitor for observation by a practitioner, etc.

[0030] The configuration of the operating unit 10 is not limited to the embodiment shown in Fig. 1. A pair of angle knobs may be provided instead of the angle lever 16, and the bending portion 32 may be bent in the up-down and left-right directions by rotating the pair of angle knobs. Also, an air / 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 tip portion main body 34 by operating the air / water supply button.

[0031] [Configuration of the tip body] Fig. 2 is a perspective view of the tip body 34 from which the puncture needle is drawn, and Fig. 3 is a cross-sectional view of the tip body 34.

[0032] The configuration of each part will be described below using a three-dimensional Cartesian coordinate system of X, Y, and Z axes. The Z direction in the drawings is parallel to the longitudinal axis 38 of the tip portion main body 34 (insertion section 12). The Z(+) direction side of the Z direction in the drawings is the tip side of the tip portion main body 34, and the Z(-) direction side is the base end side of the tip portion main body 34. The Z direction in the drawings corresponds to the first direction of the present invention. The Y direction in the drawings is perpendicular to the Z direction and, in this embodiment, corresponds to the up-down direction in each drawing. The Y(+) direction side, which is one side of this Y direction, is the upward direction in the drawings, and the Y(-) direction side, which is the other side opposite to the one side of the Y direction, is the downward direction in the drawings. The X direction in the drawings is perpendicular to both the Z and Y directions and corresponds to the second direction of the present invention.

[0033] As shown in Figures 2 and 3, the tip portion main body 34 includes, from the tip side to the base end side of the tip portion main body 34, an ultrasound mounting portion 34a, an outlet forming portion 34b, and a main body portion 34c (see Figures 2 and 3).

[0034] When the tip body 34 is viewed from the X direction side, the ultrasonic transducer 50 is attached to the ultrasonic mounting portion 34a in a position tilted forward (inclined) toward the Y (-) direction with respect to the longitudinal axis 38. This ultrasonic transducer 50 is a convex type having an oscillator surface 51 on which ultrasonic vibrators that transmit and receive ultrasonic waves are arranged in an arc along the longitudinal axis 38 (first direction). Ultrasound is transmitted from the oscillator surface 51 toward a living body, and ultrasonic echoes reflected by the living tissue are received by the oscillator surface 51. This ultrasonic transducer 50 acquires a signal that generates an ultrasonic image of the lymph node. The number of ultrasonic vibrators that make up the ultrasonic transducer 50 is not limited.

[0035] The outlet forming portion 34b has a treatment tool outlet 52 that opens toward the Y(+) direction, 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). The opening forming surface 71 is a surface that is parallel to the XZ plane and extends along the Z direction, and constitutes a part of the outer circumferential surface of the tip portion main body 34. In this embodiment, the outlet 52 opens within the planar opening forming surface 71, but it may also open within a surface of various shapes, such as a curved surface, an inclined surface, or an uneven surface. In this embodiment, a puncture needle 100 used to collect lymph node tissue will be described as an example of the treatment tool.

[0036] A duct 74 is formed inside the outlet forming portion 34b and the main body portion 34c. The distal end side of this duct 74 is connected to the outlet 52, and the proximal end side of the duct 74 is connected to the treatment tool insertion channel 23 that is inserted through the insertion portion 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 duct 74 to the outlet 52, and is then led out from the outlet 52 to the outside.

[0037] The main body 34c includes an optical system housing section 82 in which the observation optical system 40 and the illumination optical system 44 are disposed. The optical system housing section 82 has a generally semi-cylindrical shape and includes a convex surface 84 and a stepped surface 85. The convex surface 84 forms part of the outer circumferential surface of the tip body 34 (optical system housing section 82). This convex surface 84 is located on the Y(+) direction side of the opening forming surface 71 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.

[0038] The step surface 85 is a slope that connects the base end side of the opening forming surface 71 and the tip side of the convex surface 84, and constitutes part of the outer circumferential surface of the tip portion main body 34. Note that the slope here also includes a vertical surface with an inclination angle of 90° with respect to the Z direction.

[0039] 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 .

[0040] The observation optical system 40 includes an observation window 40a provided in the step surface 85, and a lens system 40b and an image pickup element 40c provided in the optical system housing portion 82. 40c is a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) image sensor that captures an observation image captured through the observation window 40a via the lens system 40b. The image sensor 40c then outputs an image signal of the observation image to the system configuration device via a signal cable 56 inserted inside the insertion portion 12.

[0041] 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 emission ends of the light guides 58 are disposed behind each illumination window 44a. This allows illumination light supplied from the light source device to each light guide 58 to be emitted from each illumination window 44a.

[0042] As described above, in this tip portion main body 34, the ultrasonic transducer 50, the outlet 52, and the stepped surface 85 (observation window 40a) are arranged in this order from the tip side to the base end. That is, the outlet 52 is arranged between the ultrasonic transducer 50 and the observation window 40a. Therefore, the puncture site on the bronchial wall surface toward the lymph node by the puncture needle 100 can be observed with the observation optical system 40.

[0043] <Ultrasound Endoscope System> Next, an ultrasonic endoscope system according to an embodiment will be described. The ultrasonic endoscope system includes an endoscope 1 having a tip body 34 provided at the tip side of the insertion section 12 and an ultrasonic transducer 50 provided on the tip body 34, and an ultrasonic endoscope balloon 120 (see FIG. 7, hereinafter referred to as "balloon") that covers the outer surface of the ultrasonic transducer 50.

[0044] The configuration of the tip portion main body 34 to which the balloon 120 is attached will be described. Fig. 4 is a perspective view of the tip portion main body 34. Fig. 5 is a side view of the tip portion main body 34. Fig. 6 is a plan view of the tip portion main body 34.

[0045] The tip portion main body 34 has standing wall portions 91 on both sides of the ultrasonic transducer 50 in a width direction (X direction) that is a direction perpendicular to the first direction (Z direction) and parallel to the plane direction of the vibrator surface 51 of the ultrasonic transducer 50. The two standing wall portions 91 are formed with surfaces parallel to the YZ plane. The standing wall portion 91 does not need to be parallel to the YZ plane over the entire surface, and "parallel" includes being approximately parallel. The distance in the width direction between the two standing wall portions 91, i.e., the width of the ultrasonic mounting portion 34a, is shorter than other parts of the tip portion main body 34 (the outlet forming portion 34b and the main body portion 34c) when viewed from the Y direction (see FIG. 6).

[0046] A fixing portion of the balloon 120, which will be described later, is fixed in close contact with the upright wall portion 91, whereby the balloon is fixed to the tip portion main body .

[0047] The tip portion main body 34 also has a flat portion 93 between the ultrasonic transducer 50 and the outlet 52. The flat portion 93 is a plane that is approximately parallel to the XZ plane, and its length in the X direction is longer than its length in the Z direction. The flat portion 93 is connected to the tip side of the opening forming surface 71 described above, and the flat portion 93 and the opening forming surface 71 form an integrated flat surface.

[0048] The tip portion body 34 also has grooves 92 on both side surfaces in the X direction of the tip portion body 34 between the ultrasonic transducer 50 and the outlet port 52. In other words, as shown in FIG. 6, when the tip portion body 34 is viewed from the Y(+) direction side, the grooves 92 are disposed between the ultrasonic transducer 50 and the outlet port 52. The grooves 92 extend from both ends of the flat portion 93 to the Y(-) direction side. )Y 4 to 6, the groove 92 is provided on the base end side of the ultrasonic transducer 50, but the position where the groove 92 is formed is not limited to the base end side of the ultrasonic transducer 50, and the groove 92 may be provided on the standing wall portion 91.

[0049] As will be described later, a protrusion 122j provided on the fixing portion of the balloon 120 fits into the groove 92. The engagement of the groove 92 with the protrusion 122j makes it difficult for the balloon 120 to come off from the tip portion main body 34.

[0050] The tip body 34 has a step portion 94 on the base end side (Z(-) direction side) of the ultrasonic transducer 50, on the surface opposite the transducer surface 51 (see FIG. 5). The step portion 94 is a flat surface approximately parallel to the XY plane, and protrudes in the Y(-) direction when viewed from the Z(-) direction.

[0051] As will be described later, the step portion 94 can be locked to a locking portion 122k provided on the fixing portion of the balloon 120, thereby preventing the balloon 120 from slipping off from the tip portion main body .

[0052] [Balloon configuration] Next, the balloon of the embodiment will be described. In the figures, as in Figures 2 to 6, a three-dimensional Cartesian coordinate system of X, Y, and Z axes will be used for description. These correspond to the X, Y, and Z directions when the balloon 120 is attached to the distal end body 34. The Z(+) direction side is the distal end side, and the Z(-) direction side is the proximal end side. The Z direction in the figures corresponds to the first direction of the present invention and corresponds to the longitudinal direction of the insertion section. The Y direction in the figures is perpendicular to the Z direction and, in this embodiment, is the up-down direction in each figure. The Y(+) direction side, which is one side of this Y direction, is the upward direction in the figures, and the Y(-) direction side, which is the other side opposite to the one side of the Y direction, is the downward direction in the figures. The X direction in the figures is perpendicular to both the Z and Y directions and corresponds to the second direction of the present invention.

[0053] 7 is an assembly diagram of balloon 120 omitting the tube, where 700A in FIG. 7 is a perspective view after assembly and 700B in FIG. 7 is a perspective view before assembly. As shown in FIG. 7, balloon 120 is composed of balloon body 121 with a two-layer structure including inner portion 122 and outer portion 124.

[0054] <Inner part> The inner portion 122 has an opening 122a at one end in the first direction (Z direction), and includes two opposing side surfaces 122b, a top surface 122c, an inclined surface 122d, and a bottom surface 122e. The inner portion 122 is configured in a bottomed cylindrical shape having the opening 122a, and all parts other than the opening 122a are closed by the two side surfaces 122b, the top surface 122c, the inclined surface 122d, and the bottom surface 122e.

[0055] The opening 122a is defined by two side surface portions 122b, a top surface portion 122c, and a bottom surface portion 122e, each of which has a straight line shape, and the opening 122a has a substantially rectangular shape.

[0056] The opening 122a is inclined from the lower side (Y(-) side) to the upper side (Y(+) side) from the base end side (Z(-) side) to the tip end side (Z(+) side).

[0057] The side surface portion 122b extends along the first direction (Z direction), is composed of a surface substantially parallel to the YZ plane, and includes a first side surface portion 122f located on the side of the top surface portion 122c and the inclined surface portion 122d, and a second side surface portion 122g located on the side of the opening 122a. The distance between the opposing first side surface portions 122f is shorter than the distance between the opposing second side surface portions 122g. A step portion 122h is formed between the first side surface portion 122f and the second side surface portion 122g.

[0058] Furthermore, the inner portion 122 includes a flange portion 122i that surrounds the outer periphery of the inner portion 122. The flange portion 122i is provided on the base end side of the top surface portion 122c and on the base end side of the first side surface portion 122f, and is also provided on the bottom surface portion 122e (not shown). The flange portion 122i is made up of four connected linear portions and is provided so as to surround the outer periphery of the inner portion 122.

[0059] The inclined surface portion 122d has a shape that imitates the vibrator surface 51 of the ultrasonic transducer 50 described above, and slopes in an arc from the upper side (Y(+) side) to the lower side (Y(-) side) as it moves from the base end side (Z(-) side) to the tip end side (Z(+) side).

[0060] The side surface portion 122b has two opposing protrusions 122j on the inner surface of the second side surface portion 122g. The two protrusions 122j extend parallel to the Y direction and protrude in directions approaching each other.

[0061] <Outer part> The outer part 124 has an opening 124a at one end in the first direction (Z direction), and includes two opposing side surfaces 124b, a top surface 124c, an inclined surface 124d, and a bottom surface 124e. The outer part 124 is configured in a bottomed cylindrical shape having the opening 124a, and all parts other than the opening 124a are closed by the two side surfaces 124b, the top surface 124c, the inclined surface 124d, and the bottom surface 124e.

[0062] The two side surfaces 122b, the top surface 122c, and the bottom surface 122e that define the opening 124a are all straight, so that the opening 124a has a substantially rectangular shape.

[0063] The side surface portion 124b extends along the first direction (Z direction) and is configured as a surface approximately parallel to the YZ plane. The opening 124a of the outer portion 124 widens toward the side surface portion 124b (X direction) to accommodate the step portion 122h of the inner portion 122.

[0064] The inclined surface portion 124d has a shape that imitates the vibrator surface 51 of the ultrasonic transducer 50 described above, and is curved and inclined from the upper side (Y(+) side) to the lower side (Y(-) side) as it moves from the base end side (Z(-) side) to the tip end side (Z(+) side).

[0065] <Balloon body> As shown in 700A, the inner part 122 is housed in the outer part 124 via the opening 124a of the outer part 124, and the outer part 124 covers the inner part 122. However, the outer part 124 does not need to cover the entire inner part 122. The outer part 124 covers the two first side surface parts 122f, the top surface part 122c, the inclined surface part 122d, and a portion (on the tip side) of the bottom surface part 122e of the inner part 122. On the other hand, the outer part 124 does not cover the second side surface part 122g of the inner part 122 and a portion (on the base side) of the bottom surface part 122e.

[0066] As shown in 700A, the two side surface portions 122b and the two side surface portions 124b constituting the inner portion 122 and the outer portion 124 are arranged opposite each other, the top surface portion 122c and the top surface portion 124c are arranged opposite each other, the inclined surface portion 122d and the inclined surface portion 124d are arranged opposite each other, and the bottom surface portion 122e and the bottom surface portion 124e are arranged opposite each other.

[0067] The peripheral edge of the opening 124a of the outer part 124 abuts against the flange part 122i of the inner part 122. The relative position of the outer part 124 with respect to the inner part 122 is determined by the flange part 122i.

[0068] The outer part 124 is bonded to the inner part 122 on the side of the opening 122a to form a two-layered balloon body 121. The balloon body 121 is provided at one end of the insertion part 12 in the first direction (Z direction) and is configured in a bottomed tubular shape having the opening 122a attached to the tip part body 34.

[0069] As for the material of the balloon body 121, it is preferable that the inner part 122 and the outer part 124 are made of different materials so that the inner part 122 and the outer part 124 do not stick together. However, as will be described later, by providing a clearance between the inner part 122 and the outer part 124, it is possible to prevent the inner part 122 and the outer part 124 from sticking together. Therefore, the inner part 122 and the outer part 124 may be made of the same material. The material of the inner part 122 and the outer part 124 may be silicone rubber, natural rubber, or the like.

[0070] When the balloon 120 is attached to the tip portion main body 34, the first side surface portion 122f of the inner portion 122 and the standing wall portion 91 are arranged opposite to each other, and the inclined surface portion 122d and the ultrasonic transducer 50 are arranged opposite to each other. The side surface portion 124b of the outer portion 124 and the standing wall portion 91 are arranged opposite to each other with the first side surface portion 122f interposed therebetween, and the inclined surface portion 124d and the ultrasonic transducer 50 are arranged opposite to each other with the inclined surface portion 122d interposed therebetween.

[0071] The opening 122a provided in the inner part 122 serves as an insertion port through which the tip portion main body 34 described above is inserted. The internal space of the inner part 122 has a shape similar to that of the tip portion main body 34 and is formed in a shape smaller than the outer shape of the tip portion main body 34. The width (length in the X direction) of the two side surface parts 122b of the balloon 120 before being attached to the tip portion main body 34 is set smaller than the distance in the width direction between the two standing wall parts 91. As a result, when the balloon 120 is inserted into the tip portion main body 34 from the opening 122a of the inner part 122, the two side surface parts 122b of the inner part 122 expand in the X direction, and the contractile force that tries to return causes the side surface parts 122b to adhere closely to the standing wall parts 91, thereby fixing them in place. The two side surface parts 122b of the inner part 122 function as fixing parts that adhere closely to the tip portion main body 34.

[0072] The two convex portions 122j provided on the second side surface portion 122g constituting the side surface portion 122b of the inner portion 122 fit into the groove portion 92 of the tip portion main body 34 described above when the balloon 120 is attached to the tip portion main body 34. The two convex portions 122j that fit into the groove portion 92 of the tip portion main body 34 are provided on the side surface portion 122b that functions as a fixing portion. Note that when the groove portion 92 is provided on the standing wall portion 91, the two convex portions 122j are provided on the first side surface portion 122f constituting the side surface portion 122b.

[0073] Furthermore, by making the inside of the inner part 122 similar in shape to the tip part main body 34 and smaller in shape than the outer shape of the tip part main body 34, it is possible to closely fix the inner part 122 from the transducer surface 51 and the surface opposite to the transducer surface 51. This allows the inner part 122 to closely fix the inner part 122 to the transducer surface 51 and the surface opposite to the transducer surface 51 of the tip part main body 34, and the balloon 120 can be firmly fixed to the tip part main body 34. The inclined surface part 122d and the bottom surface part 122e of the inner part 122 function as fixing parts that closely fix the inner part 122 to the tip part main body 34.

[0074] Moreover, it is preferable that the balloon body 121 has a shape that follows the outer shape of the vibrator surface of the aforementioned ultrasonic transducer 50. By configuring the balloon body 121 in this way, the orientation of the balloon 120 when attached to the tip portion body 34 can be stabilized.

[0075] Figure 8 is a cross-sectional view of balloon 120. 800A is a cross-sectional view of balloon 120 cut along the YZ plane, and 800B is a cross-sectional view of balloon 120 cut along the XY plane. As shown in Figure 8, outer part 124 covers inner part 122, and balloon body 121 is formed by bonding outer part 124 and inner part 122 together.

[0076] As shown in 800A, the inner part 122 and the outer part 124 are bonded together, forming a closed space between the inner part 122 and the outer part 124. This space serves as a storage part 121a for storing an ultrasonic transmission medium. By storing the ultrasonic transmission medium in the storage part 121a, the transducer surface area 124f constituting the inclined surface part 124d of the outer part 124 can be expanded, and the transducer surface area 124f functions as a bulging part. The transducer surface area 124f is an area facing the transducer surface 51 of the ultrasonic transducer 50.

[0077] As described above, the reservoir 121a of the balloon 120 is formed by a closed space between the inner part 122 and the outer part 124, so the balloon 120 itself can ensure liquid-tightness. Therefore, unlike conventional methods for ensuring liquid-tightness between the distal end portion body and the balloon, the balloon 120 does not necessarily require a circular groove shape to engage the distal end portion body with the balloon. The balloon 120 makes it possible to avoid the increase in diameter and size of the distal end portion body 34 that would result from using a circular groove shape. Furthermore, the balloon 120 allows for freedom in designing the shape of the distal end portion body 34. As shown in FIG. 7, the opening 122a of the balloon 120 can be rectangular rather than circular.

[0078] It is preferable that there is a clearance between the inner part 122 and the outer part 124, and that they are not in close contact with each other. By not having the inner part 122 and the outer part 124 in close contact with each other, when supplying the ultrasonic transmission medium to the storage part 121a, it is possible to prevent the outer surface of the inner part 122 from sticking to the inner surface of the outer part 124, which would make it difficult to supply the ultrasonic transmission medium. Furthermore, as will be described later, when the inner part 122 and the outer part 124 are bonded and assembled, it is possible to prevent the inner part 122 and the outer part 124 from sticking to each other. The clearance means a state in which the outer surface of the inner part 122 and the inner surface of the outer part 124 are separated by a certain distance.

[0079] As shown in 800A, the inner part 122 and the outer part 124 are bonded together with an adhesive or the like in the area surrounded by a square. There is no clearance at the adhesive joint 121b between the inner part 122 and the outer part 124 bonded together with the adhesive. The clearance does not have to exist in the entire area between the inner part 122 and the outer part 124.

[0080] The adhesive portion 121b may be located at a position corresponding to, for example, an upper surface portion 122c (not shown) of the inner portion 122 and an upper surface portion 124c (not shown) of the outer portion 124.

[0081] The adhesive portion 121b does not expand even when an ultrasonic wave transmission medium is supplied into the balloon 120, and therefore the base end side (Z(-) side) of the balloon 120 does not expand even when the puncture needle 100 is led out from the lead-out port 52, thereby preventing the puncture needle 100 led out from the lead-out port 52 from coming into contact with the inflated balloon 120. The adhesive portion 121b can suppress expansion other than in the transducer surface region 124f, which will be described later, and functions as an expansion restriction portion. The adhesive portion 121b suppresses expansion of the base end side (Z(-) side) of the transducer surface region 124f.

[0082] The inclined surface portion 124d of the outer portion 124 includes a transducer surface region 124f and a thick portion 124g. The thick portion 124g is arranged on the other end side (Z(+) side) opposite to one end (Z(-) side) in the first direction (Z direction), and is formed with a thickness greater than the thickness of the transducer surface region 124f. The thick portion 124g prevents the tip side (Z(+) side) of the transducer surface region 124f of the outer portion 124 from expanding when the ultrasonic transmission medium is supplied to the storage portion 121a. The thick portion 124g functions as an expansion restriction portion, allowing the transducer surface region 124f to expand more effectively.

[0083] The transducer surface region 124f is formed to have a thickness thinner than other regions of the outer portion 124, including the thick portion 124g, so that the transducer surface region 124f can bulge more easily than other regions.

[0084] The bottom surface 122e of the inner part 122, which functions as a fixing part for the balloon 120, has a locking part 122k on the inside. The locking part 122k is formed of a flat surface that is approximately parallel to the XY plane, and rises in the Y(+) direction when viewed from the tip side (Z(+) side). When the balloon 120 is attached to the tip part main body 34, the locking part 122k locks with the step part 94 of the tip part main body 34 described above.

[0085] The inner portion 122 of the balloon body 121 has a communication passage 122m that communicates with the storage portion 121a on the bottom surface portion 122e opposite the transducer surface region 124f. The communication passage 122m has an opening in the Z(-) direction, and the storage portion 121a communicates with the outside via the communication passage 122m.

[0086] The tube 140 can be attached to the balloon 120 by inserting it into the communication passage 122m in the bottom surface portion 122e of the inner portion 122, which functions as a fixing portion for the balloon 120. The tube 140 may be attached to the balloon 120 in a detachable or inseparable manner. The tube 140 is a cylindrical member having a space therein that serves as a flow path. An ultrasound transmission medium can be supplied from the flow path of the tube 140 to the reservoir portion 121a in the balloon 120 via the communication passage 122m. This allows the transducer surface region 124f that constitutes the outer portion 124 of the balloon 120 to be inflated. Attaching the tube 140 to the balloon 120 eliminates the need to provide a supply pipe in the insertion portion 12 of the endoscope 1 for supplying the ultrasound transmission medium to the balloon 120, allowing the diameter of the insertion portion 12 to be reduced. Furthermore, by making the balloon 120 (and the tube 140) disposable, there is no need to clean and sterilize the tube 140. In recent years, sterilization devices have specified the minimum diameter of pipes to be sterilized, and the demands for cleaning, disinfection, and sterilization have increased. By making the tube 140 disposable, it is possible to omit the work of cleaning and sterilizing the supply pipes.

[0087] The tube 140 is configured to be less likely to expand than the balloon body 121 (the inner portion 122 and the outer portion 124). In other words, the balloon body 121 is configured to be more easily expanded than the tube 140. Making the balloon body 121 more easily expandable than the tube 140 can be achieved, for example, by making the film thickness of the balloon body thinner than the film thickness of the tube, or by using a material for the balloon body 121 with a higher expansion coefficient than the material for the tube 140.

[0088] As shown in 800B, the outer portion 124 has side portions 124b (i.e., thick portions) formed with a thickness greater than the thickness of the transducer surface region 124f on both sides of the transducer surface region 124f in a second direction (X direction) perpendicular to the first direction (Z direction). The outer portion 124 has a transition portion 124h connecting the transducer surface region 124f and the side portion 122b. The transition portion 124h becomes thicker as it approaches the side portion 124b from the transducer surface region 124f. The transition portion 124h can suppress the transducer surface region 124f from expanding in the X direction when the ultrasonic transmission medium is supplied to the storage portion 121a, and functions as an expansion restriction portion. The transition portion 124h can be formed by a portion of the Y(+) side of the side portion 124b.

[0089] As shown in 800B, in the balloon main body 121, the side surface portion 122b of the inner part 122 and the side surface portion 124b of the outer part 124 are arranged opposite each other on both sides of the transducer surface region 124f in a second direction (X direction) perpendicular to the first direction (Z(+) direction). The balloon main body 121 has an adhesive region 121c between the opposing side surface portions 122b and 124b for bonding the inner part 122 and the outer part 124 with an adhesive or the like. The adhesive region 121c functions as an expansion restrictor, suppressing the transducer surface region 124f from expanding in the X direction when an ultrasonic transmission medium is supplied to the reservoir 121a. As shown in 800B, the adhesive region 121c may be a partial region between the side surface portions 122b and 124b, or the entire region between the opposing side surface portions 122b and 124b.

[0090] As shown in 800B, the bottom surface portion 124e of the outer portion 124 has a recess 124i that is hemispherical in cross section and extends in the Z direction, approximately at the center in the width direction (X direction). The recess 124i forms part of the clearance and is a portion that communicates with the communication passage 122m of the inner portion 122. The recess 124i makes it easy to supply the ultrasonic transmission medium to the storage portion 121a.

[0091] 9 is a cross-sectional view of balloon 120 illustrating the flow of an ultrasound transmission medium supplied to balloon 120. 900A is a cross-sectional view of balloon 120 cut along the YZ plane, and 900B is a cross-sectional view of balloon 120 cut along the XY plane.

[0092] 9, the flow path through which the ultrasonic wave transmission medium is supplied to the storage portion 121a will be described. As shown in 900A, a tube 140 is attached to the communication path 122m of the outer portion 124 to supply the ultrasonic wave transmission medium to the storage portion 121a. The tube 140 is arranged on the opposite side (Y(-) side) of the transducer surface region 124f, so it does not hinder the expansion of the transducer surface region 124f. Furthermore, it does not hinder the acquisition of an observation image by the observation optical system 40.

[0093] An ultrasonic transmission medium is supplied to the balloon 120 through the tube 140. The ultrasonic transmission medium is supplied to the area having a clearance between the inner part 122 and the outer part 124 via the communication path 122m of the inner part 122. The ultrasonic transmission medium is filled between the bottom surface 122e of the inner part 122 and the bottom surface 124e of the outer part 124, and further filled between the inclined surface 122d of the inner part 122 and the inclined surface 124d of the outer part 124. The ultrasonic transmission medium is finally stored in the reservoir 121a which is mainly composed of the transducer surface area 124f and the inclined surface 122d.

[0094] As shown in 900B, the ultrasonic transmission medium is filled between the bottom surface 122e of the inner part 122 and the bottom surface 124e of the outer part 124, and further between the side surface 122b of the inner part 122 and the side surface 124b of the outer part 124. The ultrasonic transmission medium is finally stored in the reservoir 121a which is mainly composed of the transducer surface region 124f and the inclined surface 122d.

[0095] 10 is a cross-sectional view showing the state in which the transducer surface region of the balloon for an ultrasonic endoscope is inflated, and is a cross-sectional view of the balloon 120 cut along the YZ plane. As shown in FIG. 10, when the ultrasonic transmission medium is stored in the storage portion 121a, the transducer surface region 124f is most inflated.

[0096] As described above, the transducer surface region 124f, including the thick portion 124g, is formed to have a thickness thinner than other regions of the outer portion 124. This makes the transducer surface region 124f more likely to bulge than other regions.

[0097] In the region other than the transducer surface region 124f, for example, thickened portion 124g, adhesive portion 121b, transition portion 124h (not shown), and adhesive region 121c (not shown) that function as expansion restriction portions are provided. Thickened portion 124g and adhesive portion 121b prevent expansion of the region other than the transducer surface region 124f (regions in the Z(+) direction and Z(-) direction across transducer surface region 124f). Furthermore, transition portion 124h and adhesive region 121c prevent expansion of the region other than the transducer surface region 124f (regions in the X direction across transducer surface region 124f).

[0098] By expanding the transducer surface region 124f of the balloon 120 to the maximum extent, the expansion of the bottom and side surfaces of the balloon 120 can be suppressed, and when the tip body 34 equipped with the balloon 120 is inserted into a body cavity, it can be inserted further to the periphery.

[0099] The tube 140 is a member that expands least compared to the balloon 120. Therefore, when the ultrasound transmission medium is supplied to the balloon 120 through the tube 140, the expansion of the tube 140 is suppressed, and the ultrasound transmission medium can be supplied to the balloon 120 effectively.

[0100] Next, the attachment of the balloon 120 to the tip portion main body 34 will be described. FIG. 11 is a perspective view illustrating the attachment of the balloon 120 to the tip portion main body 34, with the tube omitted. 1100A shows the state before the balloon 120 is attached to the tip portion main body 34. The opening 122a of the balloon 120 is aligned with the tip side of the tip portion main body 34. 1100B shows the state after the balloon 120 has been attached to the tip portion main body 34. The opening 122a of the balloon 120 is attached to the tip portion main body 34, and the balloon 120 is attached to the tip portion main body 34. The inner part 122 covers the ultrasonic transducer 50 of the ultrasonic attachment part 34a and also covers part of the outer peripheral surface of the outlet forming part 34b other than the opening forming surface 71. The outer part 124 is positioned to cover the ultrasonic transducer 50 of the ultrasonic attachment part 34a.

[0101] As described above, at least the side surface portion 122b (not shown), which is the fixing portion of the inner portion 122, is tightly fixed to the standing wall portion 91 by the contraction force of the side surface portion 122b.

[0102] The inner part 122, which functions as a fixing part, has a flat part 122q on the base end side of the transducer surface area 124f, which functions as the expansion part of the balloon 120. The flat part 93 between the ultrasonic transducer 50 and the outlet 52 and the flat part 122q of the balloon 120 are closely fixed. In addition, by having the flat part 122q, the transducer surface area 124f and the outlet 52 are closely fixed. Between This can increase the distance between the puncture needle 100 and the inflated balloon 120, thereby preventing the puncture needle 100 from coming into contact with the inflated balloon 120. The flat portion 122q may be located at the position of the adhesive portion 121b described above.

[0103] In addition, since the balloon 120 has a shape in which the ultrasonic transducer 50 is offset as a whole, the operator can easily grasp the orientation in which the balloon 120 is attached to the tip portion main body 34 .

[0104] According to the balloon 120 of this embodiment, the inner part 122 and the outer part 124 are bonded together to form a sealed space, which serves as the storage part 121a for storing the ultrasound transmission medium. Therefore, the external shape of the tip part body 34 is not limited to a shape that ensures liquid-tightness, and can be designed taking into consideration the reduction in diameter of the tip part body 34 and the lead-out route of the puncture needle 100.

[0105] When a tube 140 is attached to the balloon 120 and the ultrasound transmission medium is supplied to the reservoir 121a via the tube 140, there is no need to provide a supply conduit in the tip body 34 of the endoscope 1, as shown in FIG.

[0106] Fig. 12 is a cross-sectional view of the tip portion main body 34, on which the balloon 120 is mounted, with the tube omitted, taken along the XZ plane. As shown in Fig. 12, the side surface portion 122b, which is the fixing portion of the inner portion 122 constituting the balloon 120, has a convex portion 122j. In addition, a groove portion 92 is provided between the ultrasonic transducer 50 and the outlet 52. The convex portion 122j fits into the groove portion 92. The fitting of the groove portion 92 and the convex portion 122j restricts movement of the balloon 120 and the tip portion main body 34 in a direction away from each other, making it difficult for the balloon 120 to come off the tip portion main body 34.

[0107] In addition, when the standing wall portion 91 has a groove portion (not shown), a convex portion (not shown) is provided on the side portion 122b of the balloon 120 facing the ultrasonic transducer 50, and this convex portion and the groove portion fit together to make it difficult for the balloon 120 to come off the tip portion main body 34.

[0108] The balloon 120 has a reservoir 121a between a transducer surface region 124f facing the transducer surface 51 and the inclined surface portion 122d.

[0109] 13 is a cross section of the tip portion main body 34, on which the balloon 120 is attached, cut along the YZ plane. As shown in FIG. 13, the tip portion main body 34 has a step portion 94 on the base end side (Z(-) direction side) of the ultrasonic transducer 50, on the surface opposite the transducer surface 51. The bottom surface portion 122e, which is the fixing portion of the inner portion 122 constituting the balloon 120, has a locking portion 122k. The locking between the step portion 94 and the locking portion 122k prevents the balloon 120 from coming off the tip portion main body 34. When the insertion section 12 of the endoscope 1, on which the balloon 120 is attached, is pulled out from the body cavity in the Z(-) direction, the balloon 120 can be prevented from falling off. In addition, the tube 140 is attached parallel to the insertion section 12 and is connected to a supply / discharge means for an ultrasonic transmission medium, such as a syringe, near the operation unit 10.

[0110] 14 is a perspective view of the balloon 120, with the tube omitted, viewed from the Z(-) direction to the Z(+) direction. The bottom surface portion 122e of the inner portion 122 has a tapered portion 122n on the base end side (Z(-) side). The tapered portion 122n slopes toward the Y(+) direction as it extends in the Z(-) direction. In addition, the two side surface portions 122b of the inner portion 122 each have a tapered portion 122p on the base end side (Z(-) side). The two tapered portions 122p slope toward each other as they extend in the Z(-) direction.

[0111] By providing tapered portion 122n, it is possible to release the force in the first direction (Z direction) in the Y direction. Furthermore, by providing tapered portion 122p, it is possible to release the force in the first direction (Z direction) in the X direction. This allows the force applied by contact with the internal tissue when inserting or removing the tip portion into or from the body cavity to be released in the Y and X directions, thereby preventing the balloon 120 from falling off from the tip portion main body 34.

[0112] Although the balloon 120 has the tapered portion 122n and the tapered portion 122p in the example, it may have only one of them.

[0113] When the ultrasound transmission medium is stored inside the storage portion 121a of the balloon body 121, the balloon 120 of the embodiment can maximally inflate the transducer surface region 124f of the outer part 124 that faces the transducer surface 51 of the ultrasonic transducer 50 by restricting a portion of the balloon body 121 with the expansion restricting portion. As a result, when the balloon 120 is expanded, the outer diameter of the balloon 120 can be reduced, and since the balloon 120 does not expand on the side opposite to the transducer surface 51, the transducer surface 51 can be stably brought into contact with the site to be observed in the body cavity via the balloon 120.

[0114] In the above embodiment, the balloon 120 has been described as having a two-layer balloon body 121 made up of an inner portion 122 and an outer portion 124, but is not limited to a two-layer balloon body 121. For example, in addition to the inner portion 122 and the outer portion 124, a separate member may be laminated to form a balloon body having a three-layer or more layer structure.

[0115] Next, a balloon of another embodiment will be described. Figure 15 is a perspective view for explaining the attachment of a balloon 150 of another embodiment to the distal end portion main body 34. The Z direction in the figure corresponds to the first direction of the present invention, and corresponds to the longitudinal direction of the insertion part.

[0116] 1500A shows the state before the balloon 150 is attached to the tip portion body 34. 1500B shows the state after the balloon 150 is attached to the tip portion body 34. Unlike the balloon 120, the balloon 150 is a balloon made up of one layer.

[0117] The structure of the balloon 150 will be described. The balloon 150 includes a balloon body 152, which has an opening 152a at one end in the first direction (Z direction), two opposing side surfaces 152b, a top surface 152c, an inclined surface 152d, and a bottom surface 152e. The balloon body 152 is configured as a bottomed cylinder having the opening 152a attached to the tip portion main body 34, and the two side surfaces 152b, the top surface 152c, the inclined surface 152d, and the bottom surface 152e block all but the opening 152a. Because the balloon body 152 is configured as a bottomed cylinder, an ultrasound transmission medium can be stored inside.

[0118] The inclined surface portion 152d has a transducer surface region 152f that faces the transducer surface 51 of the ultrasonic transducer 50. The transducer surface region 152f is configured to have a thinner film thickness than other parts of the balloon body 152, and therefore the transducer surface region 152f is configured to expand more easily than other regions.

[0119] The base end side (Z(-) side) of the side surface portion 152b has two opposing protrusions 152h. The two protrusions 152h are parallel to the Y direction and protrude in directions approaching each other.

[0120] As shown in 1500A, the opening 152a of the balloon 150 is aligned with the distal side of the tip body 34, and as shown in 1500B, the opening 152a of the balloon 150 is attached to the tip body 34, and the balloon 150 is attached to the tip body 34.

[0121] By fitting the convex portion 152h of the balloon 150 into the groove portion 92 of the tip portion body , it is possible to make it difficult for the balloon 150 to come off from the tip portion body .

[0122] By storing an ultrasonic wave transmission medium in the space defined by the balloon 150 and the distal end body 34, the transducer surface region 152f of the balloon body 152 is caused to expand.

[0123] In this case, the transducer surface region 124f can be expanded more effectively by providing an expansion restriction portion in the balloon main body 152. For example, the expansion restriction portion is a thick portion 152g arranged on the other end side (Z(+) side) opposite to one end (Z(-) side) in the first direction (Z direction) of the inclined surface portion 152d. When the ultrasonic transmission medium is supplied into the balloon main body 152, the thick portion 152g suppresses the expansion of the tip side (Z(+) side) of the transducer surface region 152f.

[0124] Another expansion restriction portion is to closely fix the two side surface portions 152b to the standing wall portion 91. The side surface portions 152b closely fixed to the standing wall portion 91 suppress the expansion of the transducer surface region 152f in the width direction (X direction) when an ultrasonic wave transmission medium is supplied into the balloon main body 152. By making the width (length in the X direction) of the two side surface portions 152b of the balloon 150 before being attached to the tip portion main body 34 smaller than the distance in the width direction (length in the X direction) between the two standing wall portions 91, the two side surface portions 152b can be closely fixed to the standing wall portion 91.

[0125] Another expansion restriction portion is that the top surface portion 152c is tightly fixed to the flat surface portion 93 of the tip portion main body 34. The top surface portion 152c that is tightly fixed to the flat surface portion 93 suppresses expansion toward the base end side (Z(-) side) of the transducer surface region 152f when an ultrasonic transmission medium is supplied into the balloon main body 152. The top surface portion 152c can be tightly fixed to the flat surface portion 93 by making the distance (length in the Y direction) between the top surface portion 152c and the bottom surface portion 152e of the balloon 150 before it is attached to the tip portion main body 34 smaller than the height (length in the Y direction) of the tip portion main body 34, which is the portion where the top surface portion 152c and the bottom surface portion 152e are tightly fixed.

[0126] In another embodiment, when an ultrasound transmission medium is stored inside the balloon body 152, the balloon 150 can maximally inflate the transducer surface region 152f of the balloon body 152 that faces the transducer surface 51 of the ultrasonic transducer 50 by restricting a portion of the balloon body 152 with an inflation restricting portion. As a result, when the balloon 150 is inflated, the outer diameter of the balloon 150 can be reduced, and the balloon 150 does not inflate on the side opposite the transducer surface 51, so that the transducer surface 51 can be stably abutted against the site to be observed in the body cavity via the balloon 150. [Explanation of symbols]

[0127] 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 34 Tip body 34a Ultrasonic mounting part 34b Outlet forming part 34c Main body 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 51 vibrator surface 52 Treatment tool outlet 54 Signal Cable 56 Signal cable 58 Light Guide 71 Aperture forming surface 74 Pipeline 82 Optical system storage section 84 Convex 85 Step surface 91 Standing wall 92 Groove 93 Plane part 94 Step 100 puncture needle 120 Ultrasound Endoscope Balloon 121 Balloon body 121a Storage section 121b Adhesive part 121c adhesive area 122 Inner part 122a opening 122b Side part 122c Top part 122d Slope section 122e Bottom part 122f 1st side part 122g 2nd side part 122h Step 122i flange 122j convex part 122k locking part 122m communication path 122n Tapered section 122p Tapered section 122q flat area 124 outer part 124a opening 124b Side part 124c Top part 124d Slope section 124e Bottom part 124f Oscillator surface area 124g thick part 124h Transition 124i recess 140 tubes 150 balloons 152 Balloon body 152a opening 152b Side part 152c Top part 152d Slope section 152e Bottom part 152f Oscillator surface area 152g thick part 152h convex part

Claims

1. A balloon for an ultrasonic endoscope is attached to cover the outer surface of an ultrasonic transducer provided on a distal end body on the distal side of an insertion section, a bottomed cylindrical balloon body having an opening provided at one end in a first direction corresponding to the longitudinal direction of the insertion portion and attached to the tip portion body, the balloon body covering the transducer surface of the ultrasonic transducer and capable of being inflated by storing an ultrasonic transmission medium therein; an expansion restriction portion that restricts a portion of the balloon body when the ultrasonic transmission medium is stored inside the balloon body, thereby allowing a transducer surface area facing the transducer surface of the ultrasonic transducer to expand most; The balloon body is an inner part having the opening at one end thereof, and an outer part covering the inner part and bonded to the opening side; a reservoir portion for storing the ultrasonic transmission medium between the inner portion and the outer portion; The outer portion is the transducer surface area; a first thick portion formed on the other end side opposite to the one end in the first direction and having a thickness greater than a thickness of the vibrator surface area; second thick portions formed on both sides of the vibrator surface area in a second direction perpendicular to the first direction, the second thick portions having a thickness greater than the thickness of the vibrator surface area; a transition portion formed between the second thickened portion and the transducer face area; Equipped with an adhesive portion that bonds together the inner portion and an extension portion that extends from the vibrator surface area of ​​the outer portion toward the one end in the first direction, the first thick portion, the transition portion, and the adhesive portion function as the bulge restricting portion; Balloon for ultrasound endoscope.

2. The first thick-walled portion forms the bottom of the balloon body, which has a bottomed cylindrical shape. The balloon for an ultrasonic endoscope according to claim 1.

3. 3. The balloon for an ultrasonic endoscope according to claim 1, wherein the inner portion and the outer portion are bonded to each other on both sides of the transducer surface area in a second direction perpendicular to the first direction, and the bonded areas function as the expansion restriction portions.

4. 4. The balloon for an ultrasonic endoscope according to claim 1, wherein the balloon body has an area smaller than the distance between the upright wall portions provided on both sides of the ultrasonic transducer before the tip portion body is attached.

5. 5. The balloon for an ultrasonic endoscope according to claim 1, wherein the balloon body has a protrusion that protrudes toward the tip body and fits into a groove formed in the tip body on the base end side of the ultrasonic transducer.

6. 6. The balloon for an ultrasonic endoscope according to claim 1, wherein the balloon body has a locking portion that locks onto a step formed on a surface of the tip body opposite the ultrasonic transducer.

Images