JP4349844B2 - The tip of a radial scanning ultrasound endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a distal end portion of a radial scanning ultrasonic endoscope provided with an ultrasonic probe for performing radial scanning and an objective optical system for optical observation.
[0002]
[Prior art]
In general, the distal end portion of the radial scanning type ultrasonic endoscope includes an ultrasonic head unit formed in a cylindrical shape including an ultrasonic probe for performing radial scanning, an objective optical system for performing optical observation, and the like. The optical system holding body to be held is arranged and fixed integrally with the optical system holding body passing through the ultrasonic head unit (for example, Patent Document 1).
[0003]
[Patent Document 1]
JP 2001-314401 A
[0004]
[Problems to be solved by the invention]
FIG. 6 is an exploded side cross-sectional view of the distal end portion of such a conventional radial scanning ultrasonic endoscope. The rear portion 92a of the optical system holding body 92 that holds the objective optical system 91 and the like is an ultrasonic wave. It is formed thick so as not to pass through the head unit 93.
[0005]
Then, the optical system holding body 92 is passed through the ultrasonic head unit 93 from the distal end side thereof, and a retaining nut 94 that prevents the optical system holding body 92 from coming out of the ultrasonic head unit 93 backward is provided. It is screwed into the tip.
[0006]
However, with such a configuration, the retaining nut 94 is present on the inner side, so that the outer edge portion R of the most distal portion of the insertion portion cannot be sufficiently rounded, so that the insertion into the body cavity is poor, and The O-ring engagement groove 95 for fixing the balloon becomes shallow, which may cause the balloon to fall off during use.
[0007]
Therefore, for example, as shown in FIG. 7, a portion 92b on the front end side of the optical system holding main body 92 is formed to a size that does not pass through the ultrasonic head unit 93, and the optical system holding main body 92 is extended from the rear end side. A retaining member 98 that passes through the sonic head unit 93 and prevents the optical system holding body 92 from slipping forward from the ultrasonic head unit 93 is connected and fixed to the rear end portion of the optical system holding body 93. It is also possible.
[0008]
However, with such a configuration, as shown in FIG. 8 illustrating the VIII-VIII cross section, the rear end of the optical system holding body 92 avoids interference with the signal line 96 drawn backward from the ultrasonic head unit 93. It becomes difficult to position the short columnar connecting member 98a for connecting the portion on the side and the retaining member 98, so that the retaining member 98 is not fixed to the optical system holding body 92 in an unstable and unstable configuration. End up.
[0009]
Therefore, the present invention can sufficiently round the edge portion of the outer edge of the most advanced portion to obtain a good insertion property, can form a groove for fixing the balloon sufficiently deeply, and each portion is positioned reliably. An object of the present invention is to provide a distal end portion of a radial scanning ultrasonic endoscope that can be configured in a fixed and stable manner.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the distal end portion of the radial scanning ultrasonic endoscope of the present invention includes an ultrasonic head unit formed in a cylindrical shape including an ultrasonic probe for performing radial scanning, and optical observation. A radial scanning ultrasonic endoscope in which an optical system holding main body for holding an objective optical system and the like is arranged in a state where the optical system holding main body passes through the ultrasonic head unit and is integrally fixed. At the tip, the rear part of the optical system holding body is made thick so as not to pass into the ultrasonic head unit, and the front part of the optical system holding body is passed from the tip side into the ultrasonic head unit. The tip of the optical system holding body is projected from the tip of the ultrasonic head unit, and the surface is formed in a shape that is continuous with both the outer edge of the ultrasonic head unit and the outer edge of the optical system holding body without any step. The retaining ring is obtained by fixing the distal end outer peripheral portion of the optical system holding body by a fixing pin is inserted from the side.
[0011]
The fixing pin may be a pipe-shaped member that forms a flow path for pouring and draining into the balloon attached to the outer peripheral portion of the distal end portion of the radial scanning type ultrasonic endoscope. A pair of front and rear circumferential grooves for attaching the balloon to the outer peripheral portion of the distal end portion of the ultrasonic endoscope are formed on the outer peripheral surface of the rear portion of the optical system holding body and the outer peripheral surface of the retaining ring. Also good.
[0012]
In addition, when a key and a key groove that are engaged with each other for positioning in the rotational direction around the axis of the retaining ring with respect to the optical system holding body are provided in the retaining ring and the optical system holding body, Directional positioning can be performed more stably.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 5 shows the overall configuration of the radial scanning type ultrasonic endoscope. A bending portion 1B that is bent by remote operation is provided at a portion adjacent to the distal end portion 1A of the flexible insertion portion 1 inserted into the body cavity. Are connected.
[0014]
A bending portion operation knob 6 and the like for bending the bending portion 1B are disposed on the operation portion 5 connected to the base end of the flexible insertion portion 1. Reference numeral 7 denotes a treatment instrument insertion port for inserting a treatment instrument into a treatment instrument insertion channel inserted and arranged in the flexible insertion portion 1.
[0015]
A video signal connector portion 8A and a light guide connector portion 8B connected to a video processor (not shown) are provided side by side at the tip of the first connecting flexible tube 8 connected to the operation portion 5, and the second An ultrasonic signal connector portion 9A connected to an ultrasonic signal processing device (not shown) is provided at the distal end of the connecting flexible tube 9.
[0016]
FIG. 1 shows a distal end portion 1A of the flexible insertion portion 1, and a plurality of members at different cross-sectional positions are shown in one drawing for easy understanding.
Reference numeral 11 denotes an ultrasonic head unit that is formed in a substantially cylindrical shape by integrating an ultrasonic probe 11a for radial scanning, a receiving member, and the like. An ultrasonic signal is transmitted and received in the vertical direction around the axis of the tip portion 1A of the head, and so-called radial scanning is performed.
[0017]
Reference numeral 20 denotes an ultrasonic signal cable for transmitting signals input to and output from the ultrasonic head unit 11. In this embodiment, an ultrasonic signal cable 20 having a flexible substrate with an insulating coating is used.
[0018]
Reference numeral 12 denotes an optical system holding main body that holds the objective optical system 13 and the like, the objective optical system 13 for observing the subject in the axial direction of the distal end portion 1A of the flexible insertion portion 1, and the objective optical system A solid-state image sensor 14 for capturing an image of the subject projected by the camera 13 is built-in and fixed.
[0019]
In addition, an imaging signal cable 15 for transmitting an imaging signal extends rearward, and the optical system holding body 12 is additionally provided with an injection / drainage tube 16 for injecting / draining into a balloon (not shown). The distal end portions of the treatment instrument insertion channel, the lamp lamp guide for illumination, etc., not shown, are also held.
[0020]
The optical system holding body 12 has a front half formed in a circular cross-sectional shape that can be inserted inside the ultrasonic head unit 11, and the rear half 12 a is the same as the outer surface of the ultrasonic head unit 11. O-ring engagement groove 19 </ b> A for locking the rear end of the balloon to the outer surface of the outer-diameter shape (that is, a shape that is too thick to be inserted into the ultrasonic head unit 11). Is formed.
[0021]
When assembling this part, the optical system holding body 12 is inserted into the ultrasonic head unit 11 from the front end side, and the stepped portion 12b formed at the middle position of the optical system holding body 12 is ultrasonicated. By bringing the head unit 11 into contact with the rear end surface, the tip portion of the optical system holding body 12 protrudes from the tip of the ultrasonic head unit 11.
[0022]
Therefore, the retaining ring 21 is fitted on the distal end portion of the optical system holding body 12 protruding from the distal end of the ultrasonic head unit 11 so that the surface of the retaining ring 21 is in contact with the outer edge of the distal end of the ultrasonic head unit 11 and the optical system. The holding body 12 is smoothly connected to both the outer edges of the front end without any step.
[0023]
In this state, the rear end face of the retaining ring 21 is in contact with the front end face of the ultrasonic head unit 11, and at the same time, the retaining ring 21 and the optical system holding body 12 are in contact with each other at the intermediate stepped portion D. Thus, the axial direction positioning of the retaining ring 21 with respect to the ultrasonic head unit 11 and the optical system holding body 12 is performed.
[0024]
On the outer peripheral surface of the retaining ring 21, an O-ring engagement groove 19 </ b> B for locking the front end portion of the balloon is formed.
In addition, a drainage hole 23 that communicates with the drainage tube 16 and is formed in the optical system holding body 12 in a direction perpendicular to the axial direction at a position behind the O-ring engagement groove 19B of the retaining ring 21. A water-injecting hole 22 of the same diameter is formed straight at the coaxial line position with the water-injecting / draining hole 23 of the optical system holding body 12, and the pipe-shaped pin made of stainless steel pipe extends over both the water-injecting / draining holes 22, 23. 24 is press-fitted from the side.
[0025]
As a result, the inside of the balloon (not shown) in which the front and rear ends are attached to the distal end portion 1A of the flexible insertion portion 1 in the O-ring engagement grooves 19B and 19A and the inside of the pouring / draining tube 16 pass through the pipe-shaped pin 24. The deaeration water can be poured and drained into the balloon.
[0026]
Further, the retaining ring 21 is mechanically positioned and fixed to the optical system holding body 12 by the pipe-shaped pin 24, so that the optical system holding body 12 does not come out backward from the ultrasonic head unit 11, The pipe-shaped pin 24 serves as a retaining pin for the optical system holding body 12 with respect to the ultrasonic head unit 11.
[0027]
Note that a water-resistant adhesive is applied to the fitting surface between the retaining ring 21 and the optical system holding body 12 and the contact surface between the retaining ring 21 and the ultrasonic head unit 11 without any gaps. They are in a joined state.
[0028]
The inner peripheral surface portion of the retaining ring 21 fitted to the tip portion of the optical system holding body 12 is shown in FIG. 3 showing the retaining ring 21 alone and in FIG. 4 which is a sectional view taken along the line IV-IV. As shown, a key 26 is projected inward.
[0029]
The key 26 engages with a linear groove-like key groove 27 formed in a direction parallel to the axis on the side surface near the tip of the optical system holding body 12, and the retaining ring 21 with respect to the optical system holding body 12 is engaged. Positioning in the rotational direction around the axis. FIG. 3 illustrates different cross-sectional positions in the upper half and the lower half.
[0030]
Since the distal end portion of the distal end portion 1A of the flexible insertion portion 1 has such a configuration, the outer edge portion R of the distal end portion of the optical system holding body 12 can be smoothly rounded with a large radius of curvature and an excellent insertion portion. In addition, the depth of the front O-ring engagement groove 19B can be sufficiently ensured, and the ultrasonic head unit 11, the optical system holding body 12, and the retaining ring 21 can be reliably positioned. A fixed and stable configuration can be obtained.
[0031]
FIG. 2 is a cross-sectional view of the rear end portion of the optical system holding body 12 shown by II-II in FIG. 1, 23 is a pouring / drainage hole into which the pipe-shaped pin 24 is press-fitted, and 27 is a key 26. It is a keyway to engage.
[0032]
The rear half 12a of the optical system holding body 12 is formed with arc-shaped long holes 18 at intervals of 90 °, for example, for passing the ultrasonic signal cable 20 extending backward from the ultrasonic head unit 11. By forming the hole through which the ultrasonic signal cable 20 passes in this way, a sufficiently large space can be secured and a sufficient amount of the ultrasonic signal cable 20 can be inserted and arranged.
[0033]
【The invention's effect】
According to the distal end portion of the radial scanning ultrasonic endoscope of the present invention, the retaining ring is fixed to the outer peripheral portion of the distal end of the optical system holding body protruding from the distal end of the ultrasonic head unit by a fixing pin inserted from the side. As a result, the ridgeline on the outer edge of the most advanced part can be sufficiently rounded to obtain good insertability, and the groove for fixing the balloon can be formed sufficiently deep, and each part is securely positioned and fixed. It is possible to obtain an excellent effect that can achieve a stable configuration.
[Brief description of the drawings]
FIG. 1 is a composite side sectional view of a distal end portion of a radial scanning ultrasonic endoscope according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line II-II in FIG.
FIG. 3 is a side sectional view of a single retaining ring of an embodiment of the present invention.
4 is a cross-sectional view taken along line IV-IV in FIG.
FIG. 5 is a side view showing the overall configuration of a radial scanning ultrasonic endoscope according to an embodiment of the present invention.
FIG. 6 is an exploded side cross-sectional view of the distal end portion of a conventional radial scanning ultrasonic endoscope.
FIG. 7 is a side sectional view of a reference example of a distal end portion of a radial scanning ultrasonic endoscope.
8 is a cross-sectional view taken along the line VIII-VIII in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1A The front-end | tip part 11 of a flexible insertion part Ultrasonic head unit 12 Optical system holding | maintenance body 12a Rear side half part 13 Objective optical system 16 Drainage tube 18 Arc-shaped long hole 19A, 19B O-ring engagement groove 20 Ultrasonic signal cable 21 Retaining ring 22 Drain hole 23 Drain hole 24 Pipe pin 26 Key 27 Key groove

Claims (4)

An ultrasonic head unit formed in a cylindrical shape including an ultrasonic probe for performing radial scanning, and an optical system holding body for holding an objective optical system for performing optical observation. In the distal end portion of the radial scanning ultrasonic endoscope that is arranged in a state of penetrating through the ultrasonic head unit and fixed integrally,
The rear part of the optical system holding body is formed thick so as not to pass through the ultrasonic head unit, and the front part of the optical system holding body is passed through the ultrasonic head unit from the front end side. The tip portion of the optical system holding body is projected from the tip of the ultrasonic head unit, and the surface is formed in a shape that is continuous with both the tip outer edge of the ultrasonic head unit and the tip outer edge of the optical system holding body without a step. The distal end portion of the radial scanning ultrasonic endoscope, wherein the retaining ring is fixed to the outer periphery of the distal end of the optical system holding body by a fixing pin inserted from the side. The radial scanning according to claim 1, wherein the fixing pin is a pipe-like member that forms a flow path for pouring and draining into a balloon attached to an outer peripheral portion of a distal end portion of the radial scanning ultrasonic endoscope. Tip of a type ultrasound endoscope. A pair of front and rear circumferential grooves for attaching the balloon to the outer peripheral portion of the distal end portion of the radial scanning ultrasonic endoscope includes an outer peripheral surface of a rear portion of the optical system holding body and an outer periphery of the retaining ring. The distal end portion of the radial scanning ultrasonic endoscope according to claim 1 or 2, wherein the distal end portion is formed on a surface. A key and a key groove that are engaged with each other for positioning in the rotational direction around the axis of the retaining ring with respect to the optical system holding body are provided on the retaining ring and the optical system holding body. Item 4. The distal end portion of the radial scanning ultrasonic endoscope according to item 1, 2 or 3.

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