JP2006255246A - Ultrasonic endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accomplish a backing function in a backing layer, and to reduce the diameter of the distal end hard part of an endoscope insertion tube. <P>SOLUTION: The backing layer 22 constituting an ultrasonic vibrator array 24 in the distal end hard part of the endoscope insertion tube 2 is formed to be a substantially cylindrical shape. One or a plurality of notched parts are formed in a part of the inner peripheral surface. One member constituting an endoscope mechanism inside the backing layer 22 is partially protruded to the notched part. Then the outer diameter of a tunnel shape passage 25 is reduced. In the ultrasonic endoscope, the notched part is formed, so as to allow the total value of a distance for the progress of ultrasonic wave transmitted from ultrasonic vibrators 21 before being made incident to the notched part and a distance for the progress after being reflected against the notched part to be longer than a distance for the reciprocation of the ultrasonic wave transmitted from the ultrasonic vibrators 21 when regularly reflected against the backing layer 22 at a part other than the notched part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic scanning ultrasonic endoscope.

The ultrasonic endoscope includes an endoscope observation means and an ultrasonic observation means for observing the inside of the body cavity at the distal end hard portion of the insertion portion, and the endoscope observation means allows, for example, forceps and other treatment tools to be inserted therethrough. It is configured by an endoscope mechanism including other means such as a treatment instrument insertion portion. As a scanning mode by the ultrasonic observation means, a so-called electronic scanning type in which a large number of ultrasonic vibrators are arranged in a predetermined direction and these ultrasonic vibrators are sequentially driven has been widely used. Yes. An observation field of view in the endoscope observation means is a direct-view endoscope having a visual field in front of the distal end hard portion of the insertion portion, and the ultrasonic scanning surface by the ultrasonic observation means is in a radial direction, that is, in a circumferential shape. Or what was made into circular arc shape made into the predetermined angle range is described in patent document 1, for example.
JP 2001-314403 A

  By the way, in the ultrasonic transducer array, a plurality of ultrasonic transducers are arranged in a cylindrical shape, and a backing layer is disposed inside thereof. The backing layer absorbs ultrasonic energy transmitted in the opposite direction to the subject when ultrasonic waves are transmitted from the ultrasonic transducer to the subject, and clearly depicts the ultrasound image. For this purpose, it is a member of an essential component. In the electronic radial type ultrasonic endoscope, the shape of the backing layer is formed in a cylindrical shape, the endoscope mechanism is inserted inside (tunnel-shaped passage), and the ultrasonic transducer is arranged outside thereof. Are arranged in a cylindrical shape. The backing layer is formed to have a predetermined thickness in order to perform the backing function. That is, the ultrasonic waves (ultrasound in the direction opposite to the subject) transmitted from the ultrasonic transducer are absorbed by the damping action of the backing layer, but the backing layer and the tunnel-like passage (the endoscope mechanism is inserted) Since the acoustic impedance is different from that of the portion), reflection occurs at the boundary between the backing layer and the tunnel-shaped passage. Since the backing layer has a cylindrical shape, the ultrasonic wave is regularly reflected at the boundary (reflected at a reflection direction of 180 ° with respect to the incident direction), and the ultrasonic wave is transmitted again following the same path. It will go to the vibrator. Therefore, in order for the backing layer to perform the backing function, the ultrasonic wave transmitted from the ultrasonic vibrator (the ultrasonic wave in the direction opposite to the subject) reciprocates between the ultrasonic vibrator and the boundary portion. Therefore, the backing layer needs to have a predetermined thickness.

  In addition, since the endoscope mechanism is inserted through the tunnel-shaped passage inside the backing layer, the tunnel-shaped passage needs to have a space necessary for enclosing the entire endoscope mechanism. Here, since each member constituting the endoscope mechanism has a different shape and structure, a part of the member may partially protrude from the central axis of the distal end hard portion. For this reason, the outer diameter of the tunnel passage is determined based on the most protruding portion of the endoscope mechanism, and the inner diameter of the backing layer is increased.

  Accordingly, when the inner diameter of the backing layer is increased, the distal end hard portion provided at the distal end of the insertion portion is increased in diameter. However, since the insertion part of the ultrasonic endoscope is inserted into the subject's body and performs various examinations and treatments, it is necessary to make the diameter as small as possible. If the diameter is increased, there is a problem that the request for reducing the diameter of the hard tip portion cannot be satisfied.

  An object of the present invention is to reduce the diameter of the hard end portion while the backing layer performs a backing function.

  An ultrasonic endoscope according to the present invention includes an endoscope observation unit including an endoscope observation unit including at least an illumination unit and an observation unit on a distal end surface of a rigid distal end portion connected to an angle portion of an insertion unit. In the ultrasonic endoscope in which the electronic scanning ultrasonic observation means is attached to the outer periphery of the attachment part of the endoscope mechanism, the ultrasonic observation means includes a plurality of ultrasonic transducers as a whole. An ultrasonic transducer array provided in an arc shape or a circumferential shape and a backing layer on the inner surface side thereof are provided, and the inside of the backing layer is used as a tunnel-like passage, and the inside of the tunnel-like passage is provided with the endoscope. A mirror mechanism is inserted and provided, and the backing layer is formed in a substantially cylindrical shape so as to contain the endoscope mechanism, and one or a plurality of notches are formed on a part of the inner peripheral surface thereof, Any member that constitutes the endoscope mechanism is partially Projecting into the notch, the ultrasonic wave transmitted from the ultrasonic transducer is reflected from the ultrasonic transducer more than the distance to reciprocate when regularly reflected by the backing layer other than the notch. The notch is formed so that the total value of the distance traveled before the transmitted ultrasonic wave enters the notch and the distance traveled after being reflected by the notch is increased. To do.

  The ultrasonic endoscope according to the present invention can reduce the diameter of the hard tip portion while sufficiently exhibiting the backing function without impairing the backing function of the backing layer.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, as shown in FIG. 1, the ultrasonic endoscope is roughly composed of a main body operation unit 1, an insertion unit 2, and a universal cord 3. The ultrasonic endoscope is connected to a light source device, a video signal processing device, and an ultrasonic observation device to constitute a system as a whole. The universal cord 3 is pulled out from the main body operation unit 1 and branches in the middle, and is connected to the light source device so as to be detachable, the connection connector 3b detachably connected to the video signal processing device, and the ultrasonic wave. A connection connector 3c is detachably connected to the observation apparatus.

  The main body operation unit 1 can be held by an operator with one hand, is provided with an angle operation means 4 and a treatment instrument introduction unit 5 and is equipped with operation buttons such as an air / water supply button 6 and a suction button 7. In addition, various switches 8 are also provided.

  The insertion portion 2 is a cord-like member having a predetermined length provided by being connected to the main body operation portion 1 and is inserted into the body of the subject. The insertion portion 2 is a flexible portion 2a that bends along the insertion path in a body cavity or the like for most of the length from the connecting portion to the main body operation portion 1, and an angle portion is provided at the tip of the flexible portion 2a. 2b is connected, and the distal end hard portion 2c is connected to the angle portion 2b. The angle portion 2b can be bent up and down and left and right by remote operation in order to point the distal end hard portion 2c in a desired direction. For this purpose, the main body operation unit 1 is provided with an angle operation means 4 and is controlled so that the angle portion 2b is bent by an operator's operation and the distal end hard portion 2c is directed in a desired direction.

  FIG. 2 shows the distal end portion of the insertion portion 2, and FIG. 3 shows the configuration of the distal end surface of the distal end hard portion 2 c in the insertion portion 2. As is clear from these drawings, the distal end hard portion 2c has an endoscope observation means having a predetermined viewing angle V with the direction of extension of the axis thereof, that is, the front of the distal end hard portion 2c as a visual field. Electronic radial scanning ultrasonic observation means having a circular or arcuate ultrasonic scanning surface W at a position on the base end side from the field of view of the mirror observation means is provided.

  FIG. 4 shows a cross section of the distal end portion of the insertion portion 2. As is apparent from FIG. 3, the endoscope observation means includes an illuminating unit 10 and an observing unit 11, and the illuminating unit 10 is disposed on both sides of the observing unit 11. The illumination unit 10 includes an illumination lens 10a facing the distal end surface of the distal end hard portion 2c, and a light guide 10b (see FIG. 5). The light guide 10b includes an optical fiber bundle, and is connected to the connection connector 3a of the universal cord 3. It extends to the distal end hard portion 2c of the insertion portion 2, and the illumination light emission end faces a position facing the illumination lens 10a. On the other hand, the observation unit 11 includes an objective lens 11a and a prism 11b that bends the optical path from the objective lens 11a by 90 °. The objective lens 11a is provided in the lens barrel 12, and the prism 11b is fixed to the lens barrel 12. Provided. A solid-state image sensor 13 is joined to the prism 11b, and a predetermined number of signal lines are connected to the first substrate 13a of the solid-state image sensor 13. In addition to the first substrate 13a, a second substrate 13b for fixing an electronic component 13c such as a capacitor required when transmitting a signal from the solid-state imaging device 13 via a signal line is a first substrate. It is arranged at the top of 13a. Signal lines from the solid-state imaging device 13 and the electronic component 13 c are bundled and extended as a single video cable 14 to the connection connector 3 b of the universal cord 3.

  The distal end surface of the distal end hard portion 2c of the insertion portion 2 is further provided with a treatment instrument derivation opening 15 for deriving forceps and other treatment instruments. A connection pipe 16 to which a treatment instrument insertion tube from the treatment instrument introduction portion 5 provided in the apparatus is connected is attached. Further, the treatment instrument insertion tube is configured to join the suction passage inside the main body operation unit 1. Furthermore, a nozzle 17 is mounted on the hard tip portion 2c for cleaning when the tip surface of the objective lens 11a in the observation unit 11 is soiled with body fluid or the like. The nozzle 17 is connected to a cleaning fluid supply tube 9 operated by the air / water supply button 6. Therefore, these also function as an endoscope mechanism that constitutes the endoscope together with the endoscope observation means.

  Although the endoscope mechanism is configured as described above, the distal end portion of each member constituting the endoscope mechanism is fixedly held by the endoscope mounting member 18. The endoscope mounting member 18 is made of a metal material such as stainless steel having a plurality of through holes through which the members constituting the endoscope mechanism described above are inserted, and a distal end cap 19 projects from the endoscope mounting member 18. The distal end cap 19 prevents the endoscope mounting member 18 made of a metal material from being exposed to the outside, and the distal end block is configured by the endoscope mounting member 18 and the distal end cap 19. . As shown in FIG. 4, the tip cap 19 is formed with two screw holes 19a in the thickness direction, and set screws 20 are screwed into these screw holes 19a. The distal end of the set screw 20 is brought into pressure contact with the endoscope mounting member 18 and the abutment surface between the endoscope mounting member 18 and the distal end cap 19 is bonded to thereby constitute the endoscope mounting member 18 and the distal end cap 19. The tip block is integrated.

  Ultrasonic observation means having a radial scanning surface is attached to the proximal end side position of the distal end cap 19 in the distal end rigid portion 2c. As is apparent from FIG. 5, this ultrasonic observation means has a large number of ultrasonic transducers 21 arranged in the circumferential direction so that the transmitting and receiving surfaces thereof face the axial direction of the distal end hard portion 2c. The sound wave vibrators 21 are arranged in a circumferential shape or a circular arc shape (for example, about 270 °) so as to perform electronic scanning. A backing layer 22 is attached to the inner peripheral side of the ultrasonic transducers 21 arranged in this way, and a large number of these ultrasonic transducers 21 are fixed on the backing layer 22 by means such as adhesion. In addition, an acoustic lens 23 is provided on the outer peripheral surface of the ultrasonic transducer 21, and an ultrasonic transducer array 24 having a cylindrical shape as a whole is formed. A cable 40 is connected to each ultrasonic transducer 21, and these cables 40 are bundled one by one or plurally and are extended from the insertion portion 2 to the main body operation portion 1.

  As described above, the ultrasonic transducer array 24 has a cylindrical shape, and the inner peripheral surface thereof is a tunnel-shaped passage 25. Accordingly, each member constituting the endoscope mechanism is inserted into the tunnel-shaped passage 25 formed by the inner peripheral surface of the backing layer 22 in the ultrasonic transducer array 24 so as to be closer to the distal end than the ultrasonic transducer array 24. And is fixed to an endoscope mounting member 18 covered with a tip cap 19. Further, the proximal end portion of the endoscope mounting member 18 is a large-diameter stepped portion 18a, and the distal end portion of the acoustic lens 23 constituting the ultrasonic transducer array 24 extends to a front position from the ultrasonic transducer 21. Then, the ultrasonic transducer array 24 is fixed by means of adhesion or the like so as to protrude onto the large-diameter stepped portion 18a of the endoscope mounting member 18. Further, the proximal end side of the ultrasonic transducer array 24 is in contact with the connecting member 32 connected to the most advanced ring 30a of the angle ring 30 constituting the structure of the angle portion 2b by the screw 31, and the gap is bonded between them. It will be fixed by.

  Here, as shown in FIG. 4, in the tunnel-shaped passage 25 inside the backing layer 22, as an endoscope mechanism, a prism 11 b constituting the observation unit, the individual imaging device 13, and the first substrate 13 a. The second substrate 12b, the electronic component 13c, and the tip portion of the video signal cable 14 are located. Further, the light guide 10b (see FIG. 5) constituting the illuminating unit 10, the connection pipe 16 constituting the treatment instrument insertion path, and the air / water supply tube 9 (see FIG. 5) are arranged inside the backing layer 22. Has been. Accordingly, various members are inserted into the tunnel-shaped passage 25. In the cross-sectional view taken along the line A-A in FIG. 5, the electrons constituting the endoscope mechanism are viewed from the central axis of the tunnel-shaped passage 25. The tip portion of the component 13c protrudes to the outermost side.

  As described above, when the backing layer 22 is formed in a cylindrical shape and includes all the members inserted through the tunnel-shaped passage 25, the backing layer 22 is included so as to include the portion protruding outward. It is necessary to form the cylindrical shape of the layer 22. Accordingly, the inner diameter of the backing layer 22, that is, the outer diameter of the tunnel-shaped passage 25 is determined with reference to the outermost protruding portion of each member inserted through the tunnel-shaped passage 25, that is, the tip portion of the electronic component 13 c. Is done.

  In the present invention, the backing layer 22 is formed in a substantially cylindrical shape, one or a plurality of notches are formed in a part of the inner peripheral surface of the backing layer 22, and the tunnel-like passage 25 is inserted into the notch. A part of each member (a part protruding outward) is protruded. When the notch is formed in one place, the outermost projecting part of each member is projected into the notch, and when a plurality of notches are formed, the parts are sequentially projected outward. Project into the notch from what it is. Thereby, it is not necessary to determine the outer diameter of the tunnel-shaped passage 25 with reference to the protruding portion of the members constituting the endoscope mechanism having different shapes and structures. When the notch is formed at one place, the outer diameter of the tunnel-shaped passage 25 can be determined based on the next protruding part, and when it is formed at two places, the next The outer diameter can be determined on the basis of the protruding part. Accordingly, the outer diameter of the tunnel passage 25 (the inner diameter of the backing layer 22) can be reduced, and the diameter of the distal end hard portion 2c of the endoscope insertion portion 2 can be reduced. Of course, when a large number of notches are formed, the distal end hard portion 2c can be made thinner.

  For example, in FIG. 5, since one notch is formed on the inner peripheral surface of the backing layer 22 corresponding to the electronic component 13c and the electronic component 13c protrudes from the notch, the tip portion of the electronic component 13c It is not necessary to determine the outer diameter of the tunnel-like passage 25 on the basis of In this case, the outer diameter of the tunnel-shaped passage 25 is determined so as to enclose the connection pipe 16 projecting outward next. Therefore, compared with the case where the inner diameter of the backing layer 22 is formed so as to enclose the front end portion of the electronic component 13c as described above, the one in which the cutout portion is formed and the electronic component 13c protrudes is formed in a tunnel shape. The outer diameter of the passage 25 can be reduced. Thereby, the front-end | tip hard part 2c can be made into a small diameter.

  By the way, when the notch is formed in the backing layer 22, the distance between the notch and the ultrasonic transducer 21 becomes shorter than other parts. For example, as shown in FIG. 6, a distance D (backing) until the ultrasonic wave transmitted from the ultrasonic transducer 21 </ b> A (one of the ultrasonic transducers 21) reaches the inner peripheral surface of the backing layer 22. And the distance D1 until the ultrasonic wave transmitted from the ultrasonic transducer 21B (one of the ultrasonic transducers 21) reaches the notch, D1 <D. Become. Since the backing layer 22 is configured to have a minimum thickness necessary for absorbing ultrasonic waves, the ultrasonic waves transmitted from the ultrasonic transducer 21A are reflected by the inner peripheral surface of the backing layer 22. It is absorbed at the distance between the round trips, that is, the distance D + D = 2 × D. Therefore, when the ultrasonic wave transmitted from the ultrasonic transducer 21B is reflected by the notch and the ultrasonic wave reciprocates at a distance D1 shorter than the distance D, the ultrasonic wave cannot be absorbed, and the backing layer 22 has a sufficient backing function. Can not fulfill.

  However, the ultrasonic wave incident on the notch is reflected toward the ultrasonic vibrator 21C (one of the ultrasonic vibrators 21) different from the ultrasonic vibrator 21B that is the transmission source. Therefore, the distance D1 traveled by the ultrasonic wave transmitted from the ultrasonic transducer 21B before entering the cutout portion, and the distance traveled by the ultrasonic wave reflected by the cutout portion (from the cutout portion to the ultrasonic transducer). (D1 + D2) so that the total value (D1 + D2) with the distance D2 to 21C is longer than the ultrasonic reciprocation distance 2 × D when the ultrasonic transducer 21A is reflected by the inner peripheral surface of the backing layer 22 Cutouts are formed so that ≧ 2 × D). Thereby, since the ultrasonic wave incident on the notch is also completely absorbed inside the backing layer 22, the backing function can be sufficiently achieved.

  FIG. 5 shows an example in which the shape of the cutout portion becomes gradually sharper from the inner peripheral side (backing layer 22 side) toward the outer peripheral side (ultrasonic transducer 21 side). In this shape, the reflection angle becomes smaller toward the outer peripheral portion, and the reflection angle becomes larger toward the inner peripheral portion. When the reflection angle becomes small, a long distance traveled by the ultrasonic wave after reflection can be secured, and the damping action of the backing layer 22 can be sufficiently exhibited. On the other hand, when the reflection angle increases, the distance traveled by the ultrasonic wave after reflection cannot be increased, but the reflection angle increases at the inner peripheral part, so that the ultrasonic wave is transmitted to the reflection surface after transmission. Sufficient distance to reach can be taken. Therefore, the damping action of the backing layer 22 can be sufficiently exerted.

  The description has been given of the case where one notch is formed on the inner peripheral surface of the backing layer 22, but a plurality of notches may be formed in the backing layer 22. For example, when cutout portions are formed at two locations corresponding to the electronic component 13c and the connection pipe 16, the light guide 10b, which is a member that protrudes to the outside, is used as a reference outside the tunnel-shaped passage 25. The diameter can be determined. Therefore, the outer diameter of the tunnel-like passage 25 can be reduced, and the distal end hard portion 2c can be further reduced in diameter.

  Here, when one or a plurality of cutout portions are formed on the inner peripheral surface of the backing layer 22 and a part of the members constituting the endoscope mechanism is partially protruded through the cutout portions, the distal end hard portion 2c. However, the filling rate of the hard tip portion 2c is increased, and the portion is hardened. However, since the distal end hard portion 2c of the endoscope insertion portion 2 is originally a hard member, it does not need to have flexibility, and even if the filling rate of the distal end hard portion 2c is increased, there is no particular problem.

  As described above, according to the present invention, the backing layer is formed in a substantially cylindrical shape, one or a plurality of notches are formed in a part of the inner peripheral surface thereof, and inserted into the tunnel-shaped passage inside the backing layer. The outer diameter of the tunnel-shaped passage can be reduced by partially projecting a part of the members constituting the endoscope mechanism. For this reason, the diameter of the distal end hard portion 2c can be reduced. At this time, the distance between the ultrasonic transducer and the notch is shortened, but the distance traveled by the ultrasonic wave before entering the notch and the distance traveled by the ultrasonic wave reflected by the notch By forming the notch so that the total length of the ultrasonic wave transmitted from the ultrasonic transducer is longer than the reciprocal distance when the ultrasonic wave is regularly reflected on the inner peripheral surface of the backing layer, the ultrasonic wave is A distance traveling inside can be secured, and all ultrasonic transducers can perform a sufficient backing function.

1 is an overall configuration diagram of an ultrasonic endoscope showing an embodiment of the present invention. It is an external view of the front-end | tip part of an insertion part. It is a figure which shows the front end surface of a front-end | tip hard part. It is a longitudinal cross-sectional view which shows a front-end | tip part from the angle part of an insertion part. It is AA sectional drawing of FIG. FIG. 6 is an enlarged view of FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body operation part 2 Insertion part 2a Soft part 2b Angle part 2c Hard tip part 10 Illumination part 10a Illumination lens 10b Light guide 11 Observation part 11a Objective lens 11b Prism 12 Lens tube 13 Solid-state image sensor 13a Substrate 13c Electronic component 18 Internal view Mirror mounting member
19 Tip Cap 21 Ultrasonic Vibrator
22 backing layer 24 ultrasonic transducer array 25 tunnel passage

Claims (2)

An endoscope mechanism including an endoscope observation means including at least an illumination part and an observation part is attached to the distal end hard part provided connected to the angle part of the insertion part. In an ultrasonic endoscope in which an electronic scanning ultrasonic observation means is mounted on the outer periphery of the mounting portion,
The ultrasonic observation means has a configuration including an ultrasonic transducer array in which a plurality of ultrasonic transducers are provided in a circular arc shape or a circumferential shape, and a backing layer on the inner surface side thereof,
The inside of the backing layer is used as a tunnel-shaped passage, and the endoscope mechanism is inserted through the tunnel-shaped passage.
The backing layer is formed in a substantially cylindrical shape so as to contain the endoscope mechanism, and one or a plurality of notches are formed on a part of the inner peripheral surface thereof, and any of the endoscope mechanism is configured. Such a member partially protrudes into the notch,
The ultrasonic wave transmitted from the ultrasonic transducer is more than the distance traveled when the ultrasonic wave transmitted from the ultrasonic transducer is regularly reflected by the backing layer other than the cutout portion. The ultrasonic endoscope is characterized in that the cutout portion is formed so that a total value of a distance traveled before being incident on and a distance traveled after being reflected by the cutout portion becomes long. The ultrasonic endoscope according to claim 1, wherein the notch has a shape that gradually becomes sharper from the inner peripheral side to the outer peripheral side of the backing layer.

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