JP5161420B2 - Endoscope insertion part - Google Patents

Description

  The present invention relates to an endoscope in which a hard tip portion is formed at the tip of an angle portion, and particularly to an insertion portion having a small diameter structure that can be inserted nasally.

  Endoscopes used for medical purposes are provided with a main body operation part connected to an insertion part into a body cavity, and at least a universal cord detachably connected to the light source device from the main body operation part. This is generally constituted by The insertion part is composed of a flexible part that bends in an arbitrary direction along the insertion path for most of the length from the connection part to the main body operation part. The flexible part has an angle part, and the angle part has A hard tip is provided continuously. The distal end hard portion is attached to the distal end surface (or the distal end side surface portion) with an endoscope observation means including an illuminating means and an imaging device, and the distal end of the treatment instrument insertion channel is open. The angle portion can be bent by a remote operation from the main body operation portion in order to direct the distal end hard portion in a desired direction.

  As an insertion path of an insertion portion of an endoscope, an endoscope for the upper digestive tract is generally inserted orally. However, when the insertion portion is inserted from the oral cavity, a pharyngeal reflex occurs, which causes discomfort and pain to the subject. In addition, since the insertion part is inserted while the subject holds the mouthpiece, the mouth breathing may be hindered and the conversation with the operator becomes difficult. .

As a path through which the endoscope can be inserted, it is possible to insert through the nasal cavity as well as the oral cavity. Although the inside of the nasal cavity is a narrow path, there is a restriction that a small-diameter insertion section must be used, but the burden on the subject is mild compared to an endoscope that is inserted into the oral cavity. It is. For this reason, for example, also in Patent Document 1, a nasal insertion method is desirable from the viewpoint of subject protection and the like, and as reported in Non-Patent Document 1, a small-diameter endoscope is used. There have been reports of clinical cases in which endoscopy was performed using the From the present situation where endoscopes having a thin insertion portion having a diameter of 6 mm or less are put into practical use, endoscopic examinations by a method of inserting nasally will tend to be frequently used in the future.
JP 2005-74035 A 54th Annual Meeting of the Japanese Gastroenterological Endoscopy Society 39 (Suppl.2) 1997 VS6-2

  By the way, in the endoscope inserted transnasally, as already explained, the insertion path is narrow, but the most narrowed part is usually the nasal septum, the middle turbinate and the turbinate. It is a space between. Moreover, for example, nasal septal curvature and other congenital or acquired structures of the nasal passage may differ significantly depending on the individual subject. Therefore, a very careful operation is required for the operator who operates the endoscope. Here, the insertion part has a structure that can be bent except for the hard tip part, but the angle part connected to the hard tip part performs a bending operation, unlike the soft part that bends freely along the insertion path. This is the first time to bend, and when the bending operation is performed, the entire angle portion is bent. Since the nasal passage is a narrow path and the width, shape, etc. of the path differ depending on the subject, it is extremely difficult to perform the operation of passing the narrowed part of the nasal passage by bending the angle part. It may cause pain to the subject such as the possibility of pressing the mucous membrane.

  From the above, while the insertion part is moving in the nasal cavity, the angle part follows the curved path as much as possible, and after the insertion part has passed through the nasal cavity, the position and direction of the distal hard part is changed. In order to stabilize, it is desirable that the angle portion be held stably so as not to bend except during the bending operation. However, since it is necessary to reduce the diameter of the insertion portion, it is not possible to adopt a configuration in which the function can be switched between a state where the angle portion can be freely bent and a state where the angle is bent based on the operation.

  The present invention has been made in view of the above points, and the purpose of the present invention is to make it possible to easily follow a bent insertion path without detracting from the function of the angle portion. It is to provide an insertion part of an endoscope.

In order to achieve the above-described object, the present invention has a distal end rigid portion having an endoscope observation means attached to the distal end, and in order to direct the distal end rigid portion in a desired direction, the proximal end side of the distal end rigid portion In the insertion portion of the endoscope provided with an angle portion, the endoscope is inserted nasally, the diameter of the insertion portion is 6 mm or less, the distal end hard portion and the angle portion, In the meantime, when a load of a predetermined set value or more is applied, a flexible part that bends following this load is interposed, and the flexible part is bent straight by an external force. An outer ring layer to be restored to a state, an end ring to which a tip body is coupled, a first node ring body pivoted so as to be bent in the vertical direction with respect to the end ring, and the first ring A second joint ring pivotally attached to the first joint ring so as to be bent in the left-right direction; and the second joint ring A tip ring pivotally mounted so as to be bent in the vertical direction, and an operation wire is fixed to the tip ring, and the tip ring is vertically operated by operating the operation wire. An angle ring pivoted so as to be curved is provided.

  Here, the insertion portion is composed of a distal end rigid portion, an angle portion, and a flexible portion from the distal end side, and a proximal end portion of the flexible portion is connected to the main body operation portion. Of this insertion portion, the hard tip portion is a portion that cannot be bent. The soft part has a structure that bends due to the action of an external force and bends in any direction. The angle portion can be bent itself, but bends based on an operation from the main body operation portion. However, in order to stably hold the hard tip portion, it is not easily bent by the action of an external force.

  When the insertion portion is inserted into the body cavity, the distal end of the insertion portion may come into contact with the body wall constituting the insertion path. When the insertion path is wide, the distal end hard part can be directed in the direction of the insertion path by adjusting the direction of the distal end hard part by bending the angle part. However, when there is a large bend in the insertion path as in the nasal cavity and the path itself is narrow, it may be difficult to adjust the direction of the insertion section by curving the angle portion. . Nevertheless, forcibly pushing the insertion part will cause pain to the subject and the progress of the insertion part will be hindered. By providing a flexible portion on the proximal end side of the distal end hard portion, when the distal end of the insertion portion hits the inner wall of the body cavity, the flexible portion bends to deviate the direction of the distal end hard portion and follow the direction of the insertion path. In this way, it can proceed smoothly. As described above, the direction is automatically adjusted by the flexible portion, so that the insertion portion can be smoothly inserted into an insertion path that is not constant depending on the subject, such as a nasal cavity.

  When the distal end hard part of the insertion part is oriented in an appropriate direction with respect to the insertion path, the angle part is appropriately curved so that the entire insertion part is along the insertion path, thereby reducing pain to the subject. can do. Therefore, an angle portion is provided on the proximal end side of the flexible portion, and it is desirable that an operation wire for bending the angle portion is positioned near the flexible portion.

  In order to smoothly advance the insertion portion in the thin insertion path, it is desirable that the flexible portion be easily bent in any direction. However, the narrow path such as the nasal cavity is a path that guides the distal end of the insertion part to a predetermined observation target part, and the distal end hard part passes through this path and moves to the inside of the organ to be observed or inside the organ. When starting the observation inside the body cavity, it is necessary to stably hold the hard tip portion in order to enable accurate observation.

  From the above, when a load of a certain value or more is applied in order to stably hold the distal end hard part during endoscopic observation and to be able to smoothly insert it into a thin and curved path The distal end hard portion is bent around the flexible portion. Here, how much load is applied to the distal end hard part, the flexible part bends and the direction of the distal end hard part changes, the pain of the subject is reduced, the insertion operability of the insertion part, and the observation Therefore, it is set in consideration of ensuring the stability of the hard tip portion. Further, since the bending of the flexible portion is for adjusting the direction of the distal end hard portion to face the insertion path, it is not necessary to increase the maximum bending angle too much. The bending angle with respect to the central axis when the insertion portion is in a straight state is 90 ° or less, preferably 45 ° or less, and more preferably about 15 to 30 °.

  As a specific configuration of the flexible portion, a node ring structure similar to the angle ring constituting the angle portion can be used. In other words, the angle ring of the angle part is extended by a predetermined length, and the distal end of the operation wire is not fixed to the node ring body constituting the flexible part, but is operated on the ring at a position closer to the proximal end than that. Secure the wire. In addition, in the insertion part, a soft part is continuously provided on the base end side of the angle part. A metal band similar to the soft part is wound between the tip hard part and the angle part. By doing so, a flexible part can also be comprised. Further, the flexible portion can be constituted by a coil-like member such as a metal or a flexible sleeve.

  By configuring as described above, it is possible to smoothly perform the operation of inserting the insertion portion through the thin and bent insertion path, and the pain given to the subject is minimized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, an endoscope insertion portion is inserted through a subject's nasal cavity and used for an upper digestive tract such as the esophagus, stomach, duodenum, and the like.

  First, as shown in FIG. 1, the insertion portion 2 of the endoscope 1 passes through a narrow path from the outer nostril that is the entrance of the nasal passage through the nasal passage including the middle nasal passage or the lower nasal passage, and from the rear nostril to the nasopharynx It will be introduced to the esophagus through the department. In this insertion path, the narrowest part is a gap formed between the nasal septum and the middle turbinate and lower turbinate in the part indicated by A in FIG.

  The endoscope 1 is roughly configured by the insertion portion 2 described above, a main body operation portion 3 and a universal cord 4 to which the insertion portion 2 is connected. The insertion portion 2 is composed of a flexible portion 2a in which a predetermined length is bent from the connecting portion to the main body operation portion 3 in an arbitrary direction, and an angle portion is provided at the distal end portion of the flexible portion 2a. 2b is connected, and a hard tip portion 2c is connected to the tip of the angle portion 2b. The universal cord 4 is detachably connected to a processor equipped with a light source device (not shown) and a video signal processing circuit.

  FIG. 2 shows a cross-sectional structure of the distal end portion of the insertion portion 2 of the endoscope 1. In FIG. 2, a portion from the distal end hard portion 2c to the distal end portion of the angle portion 2b is shown, and the flexible portion 2a is not shown, but the configuration of the flexible portion 2a is conventionally known, The illustration and detailed description of the specific configuration are omitted.

  As is clear from FIG. 2, the distal end hard portion 2 c in the insertion portion 2 includes a distal end portion body 10 and an insulating cap 11, and the distal end portion body 10 is connected to the end ring 12. Therefore, specifically, the distal end hard portion 2 c is configured from the insulating cap 11 to the proximal end portion of the end ring 12. An observation means 5 is attached to the distal end hard portion 2c. The observation means 5 includes an objective optical system 5a and a solid-state image sensor 5b. Although not shown, illumination means for irradiating illumination light is attached to the left and right sides of the attachment part of the observation means 5 on the distal end surface of the distal end hard part 2c. These illumination means and observation means constitute an endoscope observation means. Furthermore, a treatment instrument insertion path 6 is provided in the insertion portion 2, and the treatment instrument insertion path 6 includes a treatment instrument insertion pipe 6 a made of a hard pipe and a treatment instrument insertion that is fitted to the treatment instrument insertion pipe 6 a. The treatment instrument insertion pipe 6a is open to the distal end surface of the distal end hard portion 2c.

  The angle portion 2b can be bent by remote operation so that the hard tip portion 2c is directed in a desired direction. Here, the bending direction of the angle portion 2b is set to be two directions of up and down or four directions of up and down, left and right, but in this embodiment, the bending operation is made possible in four directions of up and down and left and right. The angle portion 2b is constructed by pivoting the angle ring 13 with the pivot pin 14 at two locations, up and down and left and right. A net 15 made of a braided metal wire is covered on the outer periphery of the plurality of angle rings 13 connected in this way, and the net 15 is covered with an outer skin layer 16 made of an elastic tube. . Inside the angle ring 14 constituting the angle portion 2b, operation wires 17 are mounted at four locations at equal intervals in the circumferential direction. Therefore, the angle portion 2b is bent vertically and horizontally by pushing and pulling the operation wire 17.

  The bending operation of the angle portion 2 b is performed by remote operation from the main body operation unit 3. For this purpose, the main body operation unit 3 is provided with an angle knob 7. The operation wire 17 is wound around a pulley (not shown) rotated by the angle knob 7, and the distal end portion extends to the position of the distal end ring 13 a located at the foremost end of the angle ring 13. ing. And in order to position each operation wire 13 in the circumferential direction, each operation wire 13 is sequentially inserted through a through hole 14 a provided in the pivot pin 14. In addition, a cut-out portion 18 for fixing the tip end portion of the operation wire 13 is formed on the tip ring 13 a, and the tip end portion of the operation wire 17 is fixed to each cut-out portion 18.

  The distal end hard portion 2c extends to the proximal end portion of the end ring 12, and the distal end position of the angle portion 2b is a distal end ring 13a. A flexible portion 2d is provided between the angle portion 2b and the hard tip portion 2c. The flexible portion 2d is composed of a first node ring body 21 pivotally attached to the end ring 12 with a pivot pin 20 and a second node ring body 23 pivotally attached to the tip ring 13a with a pivot pin 22. The pivot pins 20 and 22 are provided at two positions on both the left and right sides, that is, at positions orthogonal to the paper surface of FIG. Therefore, the distal end hard portion 2c can be bent up and down by the pivot pins 20 and 22. Further, the first node ring body 21 and the second node ring body 23 are pivotally attached to the upper and lower end portions of the paper by pivot pins 24 and 24. Thereby, the distal end hard portion 2c can be bent left and right.

  Here, the first and second node rings 21 and 23 have the same configuration as the angle ring 13, and the pivot pins 20, 22, and 24 are pivot pins that are pivotally mounted between the angle rings 13 and 13. Although it is the same structure as 14, the through-hole which penetrates an operation wire is not provided. The net 15 and the outer skin layer 16 extend from the end ring 12 to a position covering the tip end body 10 through the flexible portion 2d.

  With this configuration, the angle portion 2b can be bent by operating the angle knob 7. However, the portion bent on the proximal end side of the distal end ring 13a is bent by this operation. Even if 2b is curved, the flexible portion 2d is held in a straight traveling state so as to be continuous with the distal end hard portion 2c. The flexible portion 2d is bent when an external force is applied. On the other hand, the angle portion 2b is bent only when the angle knob 7 is operated and the upper and lower pairs or the left and right operation wires 17 and 17 are paired and one is pulled and the other is slack. Even if an external force acts on the angle portion 2b, the operation wire 17 is held so as not to be easily bent due to a tension acting on the operation wire 17.

  When an external force acts on the distal end hard portion 2c in the direction indicated by the arrow in FIG. 2 (this direction is referred to as the vertical direction), the pivot pin 20 between the end cap 12 and the first nodal ring body 21, Or it will bend in the up-and-down direction centering on either one or both of the pivot pin 22 between the 2nd node ring body 23 and tip ring 13a. Further, when an external force is applied in a direction orthogonal to the arrow in FIG. 2 (this direction is referred to as the left-right direction), the left and right are centered on the pivot pin 24 between the first node ring body 20 and the second node ring body 21. Bend in the direction. Further, when an external force is applied in an oblique direction, the distal end hard portion 2c is bent around the pivot pins 20, 21 and 24. That is, when an external force in the bending direction acts on the distal end hard portion 2c, the bending portion 2d bends in an arbitrary direction with respect to the angle portion 2b.

  The angle of bending of the flexible portion 2d in each direction described above depends on the shape of the node ring bodies 21 and 23, and is appropriately set according to the situation in which the endoscope is used. For example, as shown in FIG. 1, in an endoscope 1 that is inserted nasally, the most narrowed and greatly bent portion A in the insertion path is easily and smoothly formed. It can be passed with minimal burden on the subject.

  Thus, as shown by a solid line in FIG. 3, when the distal end of the insertion portion 2 is advanced in the direction of arrow F from the outer nostril to the middle turbinate and lower turbinate, the path is greatly curved. Therefore, the distal end of the insertion portion 2 may be pressed against the middle turbinate. At this time, a reaction force against the pushing force acts on the distal end hard portion 2 c of the insertion portion 2. As a result, as indicated by the phantom line in FIG. 3, the flexible portion 2d located at the proximal end portion of the distal end hard portion 2c bends in the direction of the arrow T, and the posture generally follows the bending of the insertion path. Come to take. Then, by operating the angle portion 2b and continuing the insertion while curving the angle portion 2b, the insertion portion 2 can smoothly pass through this portion. Further, at this time, the subject feels a slight pressure, but since only the pressing force sufficient to bend the flexible portion 2d acts, no great pain is given. In order to reduce the pain of the subject, the resistance to bending of the flexible portion 2d is made as small as possible. However, if the resistance is too small, the distal end hard portion 2c becomes unstable during insertion or observation in the body cavity. . Therefore, considering the relationship with the path through which the insertion portion 2 is inserted, it is possible to adjust the resistance against elongation of the outer skin layer 16 and the sliding resistance generated when the pivot pins 20, 22, 24 pivot. It can set so that the resistance with respect to bending of 2 d of bending parts may become optimal. Further, the bending angle, that is, the angle of the distal end hard portion 2c with respect to the state where the insertion portion 2 is straightened is set according to the degree of bending of the route. It is appropriate to set it to about °.

  The flexible portion 2d bends when passing through a path that is largely bent as described above, but the bending of the flexible portion 2d is eliminated when it passes through this path and reaches a substantially linear path. Then, it will automatically return to a straight state. That is, when the flexible portion 2d is bent by an external force, the outer skin layer 16 is deformed so that the outer peripheral portion of the bend is extended. Therefore, when the action of the external force is eliminated, the outer skin layer 16 is subjected to a force in a direction in which it is elastically restored. For this reason, when the action of the external force on the distal end hard portion 2c is released by passing through the curved path, the flexible portion 2d is automatically and quickly restored to a straight state.

  As described above, when the insertion path of the insertion section 2 is thin and bent, the flexible section 2d bends following the path. The bending force does not act on the bending portion 2d, and the pushing thrust can be reliably transmitted to the distal end hard portion 2c, and the insertion operation of the insertion portion 2 is performed by interposing the flexible portion 2d that bends freely. There is no particular decline in sex. In addition, when the insertion portion 2 is inserted to a predetermined position and an endoscopic examination is performed in the body cavity, the angle portion 2b is appropriately bent to change the observation field of view by the distal end hard portion 2c. When the bending portion 2d performs this bending operation, the bending portion 2d is not bent gently, and the stability of the position and direction of the distal end hard portion 2c is not impaired.

  Next, FIG. 4 shows a second embodiment of the present invention. In this embodiment, as the flexible portion 30 interposed between the hard tip portion 2c and the angle portion 2b, FIG. The spiral tube 31 is formed by spirally winding a metal strip. And the holding ring 32 is extended toward the flexible part 30 from the end ring 12 which comprises the front-end | tip hard part 2c, and also hold | maintains toward the flexible part 30 also from the front-end ring 13a which comprises the angle part 2b. A ring 33 is extended. A gap B is formed between the opposite ends of the holding rings 32 and 33. A net 34 is sheathed on the spiral tube 31, and together with the net 34, the distal end side of the spiral tube 31 is fixed to the holding ring 32 and the proximal end side is fixed to the holding ring 33 by means such as soldering. The outer skin layer 14 extends beyond the flexible portion 30 to the distal end hard portion 2c.

  Also with the above configuration, when an external force is applied to the distal end hard portion 2c, the flexible portion 30 bends, and, as in the first embodiment described above, a narrow path that is greatly bent is smooth. Can be passed through. In the embodiment of FIG. 4, the bending angle of the distal end hard portion 2 c by the flexible portion 30 depends on the interval B between the holding rings 32 and 33, the width dimension of the spiral tube 31, and the winding angle. Further, the magnitude of resistance to bending depends on the thickness of the spiral tube 31 and the like.

  Further, FIG. 5 shows a third embodiment of the present invention. The flexible portion 40 of the present embodiment uses a metal coil 41 formed of a metal wire as an elastic member in place of the spiral tube 31 in the second embodiment described above. These are fixed to a holding ring 42 and a holding ring 43 which are arranged to face each other with a gap B, and a net 44 is attached to the outer peripheral portion. Also with this configuration, when an external force acts on the distal end hard portion 2c, the metal coil 41 is elastically deformed to perform an operation as a universal joint.

  FIG. 6 shows a third embodiment of the present invention, and the flexible part 50 has a flexible tube 51. The flexible tube 51 has its both ends fixed to the holding ring 52 and the tip ring 53 on the end ring 12 side, and the net 54 is attached to the outer peripheral portion. This is the same as the third embodiment. In this case, the flexible tube 51 is bonded to the net 54, and the net 54 is fixed to the holding rings 52 and 53 by welding.

It is an external view which shows the state which has inserted the endoscope which shows 1st Embodiment in this invention in a nasal cavity. It is sectional drawing of the front-end | tip part of the insertion part in the endoscope of FIG. It is operation | movement explanatory drawing about 1st Embodiment. It is sectional drawing of the front-end | tip part of the insertion part in 2nd Embodiment in this invention. It is sectional drawing of the front-end | tip part of the insertion part in the 3rd Embodiment in this invention. It is sectional drawing of the front-end | tip part of the insertion part in 4th Embodiment in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Endoscope 2 Insertion part 2a Soft part 2b Angle part 2c Hard tip part 2d, 30, 40, 50 Flexible part 12 End ring 13 Angle ring 13a End ring 16 Outer skin layer 17 Operation wire 20, 22, 24 Pin 21 First node ring body 23 Second node ring body 31 Spiral tube 41 Metal coil 51 Flexible tube 32, 33, 42, 43, 52, 53 Retaining ring 34, 44, 54 Net

Claims (2)

In an endoscope insertion portion having a distal end rigid portion with an endoscope observation means attached to the distal end and providing an angle portion on the proximal end side of the distal end rigid portion in order to direct the distal end rigid portion in a desired direction. ,
The endoscope is inserted nasally, and the diameter of the insertion portion is 6 mm or less,
When a load of a predetermined set value or more acts between the tip hard portion and the angle portion, a flexible portion that bends following this load is interposed,
The flexible portion is covered with an outer skin layer that restores the flexible portion bent by an external force to a straight state,
An end ring to which the tip body is coupled;
A first nodal body pivotally attached to the end ring so as to be bent in the vertical direction;
A second joint ring pivotally attached to the first joint ring so as to be bent in the left-right direction;
A tip ring pivotally attached to the second node ring body so as to be bent in the vertical direction;
An operation wire is fixed to the tip ring,
An insertion portion of an endoscope, wherein the distal end ring is provided with an angle ring pivoted so as to be bent in the vertical direction by operation of the operation wire.   In order to perform the bending operation of the angle portion, a plurality of operation wires are provided, and the distal end of each operation wire is configured to be fixed at a position closer to the base end side than the flexible portion. The endoscope insertion portion according to claim 1.

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