JP2004073433A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope capable of surely collecting acoustic information and optical information for producing a mutually continuous ultrasonic tomographic image and optical tomographic image at the top end of a flexible tube in an insertion part. <P>SOLUTION: The flexible tube (100) in the insertion part of the endoscope is provided with a plurality of ultrasonic wave exchange part (110) for emitting ultrasonic waves toward a living body to collect acoustic information for the ultrasonic tomographic image, and also receiving an ultrasonic echo generated in the living body. The ultrasonic wave exchange parts are arranged so as to emit ultrasonic waves along a prescribed ultrasonic wave irradiation surface. The flexible tube (100) is also provided with a plurality of light emitting/receiving parts (114) for emitting low interference light rays toward the living body and recieving the low interference lights reflected on the living body in order to collect optical information on the optical tomographic image. The light emitting/receiving parts are arranged so as to emit the low interference light rays along a prescribed light irradiation surface which is at least partially superimposed on the ultrasonic wave irradiation surface. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is to collect acoustic information for generating a tomographic image of a living body using ultrasonic waves, and optical information for generating a tomographic image of a living body using optical coherence tomography. The present invention relates to an endoscope provided with an insertion portion flexible tube inserted into a body.
[0002]
[Prior art]
Methods for obtaining a tomographic image of a living body include irradiating the living body with ultrasonic waves, detecting ultrasonic echoes generated in the living body as a result, and generating a so-called ultrasonic tomographic image, and applying low coherence light to the living body. There is an optical coherence tomography that irradiates and detects the low coherent light reflected by a living body as a result to generate a tomographic image (hereinafter referred to as “optical tomographic image”).
[0003]
The use of ultrasound has the advantage that a tomographic image from the surface of a living body to a deep region can be obtained, but has the disadvantage that the resolution of the obtained tomographic image is low. On the other hand, when low coherence light is used, the resolution of the obtained optical tomographic image is higher than that of the ultrasonic tomographic image, but the obtained tomographic image is limited to the vicinity of the surface of the living body.
[0004]
Japanese Patent Application Laid-Open No. 11-56752 discloses a method for making use of both advantages of an ultrasonic tomographic image obtained by using the above-described ultrasonic wave and an optical tomographic image obtained by using low-coherence light to compensate for a drawback. Discloses an imaging apparatus having both a function of generating an ultrasonic tomographic image of a living body and a function of generating an optical tomographic image.
[0005]
The imaging apparatus has an insertion probe inserted into a body cavity, and one tip of the insertion probe has one ultrasonic transducer that generates an ultrasonic pulse and one light that transmits low-coherence light. And a fiber. The distal end of the insertion probe is irradiated with an ultrasonic pulse generated by the ultrasonic transducer and low-coherence light emitted from the optical fiber in directions opposite to each other and in a direction perpendicular to the center axis of the probe. It is configured to: In addition, a motor and a gear for rotating the insertion probe around its central axis are provided at the base end of the insertion probe.
[0006]
In the imaging device, by rotating the insertion probe inserted into the body cavity using the motor or the like, the so-called radial scan of ultrasonic waves and low coherence light emitted from the tip of the insertion probe is performed. As a result, an annular ultrasonic tomographic image and optical tomographic image of the body cavity are obtained. Then, the obtained two tomographic images are combined into one image in which an optical tomographic image is continuously connected to the inside of the ultrasonic tomographic image and displayed on a monitor.
[0007]
[Problems to be solved by the invention]
However, in the above-described imaging apparatus, since the radial scan for obtaining a tomographic image is achieved by mechanically rotating the insertion probe, the position of the insertion probe may be shifted during rotation. If the position of the insertion probe is shifted during the radial scan, the position on the living body where the ultrasonic diagnostic image was obtained is shifted from the position on the living body where the optical diagnostic image was obtained, and these diagnostic images are continuously displayed. A problem arises in that synthesis cannot be performed.
[0008]
An object of the present invention is to provide an endoscope having an insertion portion flexible tube having a configuration that does not cause the above-described problem.
[0009]
[Means for Solving the Problems]
In order to solve the above problem, an endoscope according to one embodiment of the present invention irradiates an ultrasonic wave toward a living body to collect acoustic information for an ultrasonic tomographic image, and generates an ultrasonic wave generated in the living body. It has an insertion section flexible tube provided with a plurality of ultrasonic transmission / reception sections for receiving echoes at its distal end. The plurality of ultrasonic transmission / reception units are arranged so that ultrasonic waves are emitted along a predetermined ultrasonic irradiation surface. Therefore, by irradiating the ultrasonic waves from each of the ultrasonic transmitting and receiving units and detecting the ultrasonic echo returning from the living body, the ultrasonic wave of the living body along the ultrasonic irradiation surface can be moved without moving the distal end of the flexible tube of the insertion unit. Acoustic information for generating an acoustic tomographic image can be collected.
[0010]
In addition, the endoscope irradiates low-coherence light toward the living body to collect optical information for an optical tomographic image on the flexible tube of the insertion section, and receives the low-coherence light reflected by the living body. A plurality of light entrances and exits are provided at the distal end. The plurality of light entrances and exits are arranged so that low coherence light is emitted along a predetermined light irradiation surface. Therefore, by irradiating low-coherence light from each of the light entrance and exit and detecting low-coherence light reflected by the living body, an optical tomographic image along the light irradiation surface without moving the distal end of the flexible tube of the insertion section Can also be obtained.
[0011]
Moreover, since the plurality of light incident portions are arranged so that the light irradiation surface at least partially overlaps the ultrasonic irradiation surface, it is possible to obtain an optical tomographic image that is reliably continuous with the above-described ultrasonic tomographic image. Can be.
[0012]
The endoscope may be configured such that, for example, a plurality of ultrasonic transmission / reception units and the plurality of light entrance / exit units are arranged substantially parallel to a longitudinal axis of a distal end portion of the insertion tube flexible tube. it can. With such a configuration, a so-called convex scan type endoscope can be provided.
[0013]
In the above case, by arranging a plurality of ultrasonic transmitting / receiving sections and a plurality of light input / output sections alternately in a line, it is possible to obtain an advantage that the outer diameter of the distal end portion of the insertion section flexible tube can be reduced.
[0014]
In addition, the endoscope may be configured such that the plurality of ultrasonic transmission / reception units and the plurality of light entrance / exit units are substantially annularly arranged along the circumferential direction of the distal end of the insertion unit flexible tube. In this case, a so-called radial scan type endoscope can be provided.
[0015]
In the above case, a plurality of optical fibers transmitting low coherence light are arranged in a ring at the distal end of the flexible tube of the insertion section, and the light input / output section controls the low coherence light emitted from each of the plurality of optical fibers. The endoscope may be configured to include a frusto-conical mirror that reflects in a radial direction (radial direction) about the central axis at the distal end portion of the insertion portion flexible tube.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an endoscope according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the vicinity of a distal end of an insertion portion flexible tube 100 in an endoscope according to an embodiment of the present invention. A rigid distal end body 102 is attached to the distal end of the insertion section flexible tube 100. In the body cavity into which the tip body 102 has been inserted, the distal end body 102 receives acoustic information for obtaining an ultrasonic tomographic image of a living body surrounding the body cavity and optical information for obtaining an optical tomographic image by optical coherence tomography. It is configured to be collected.
[0017]
More specifically, the distal end body 102 is configured to irradiate an ultrasonic pulse toward the living body from the side surface 102a and further detect an ultrasonic echo that is reflected by the living body and returned. Have been. The distal end body 102 is configured to irradiate low-interference light toward the living body from the same side surface 102a, and as a result, detect low-interference light reflected by the living body. FIG. 1 also shows an ultrasonic tomographic image and an optical tomographic image obtained based on the information collected by the distal end body 102 configured as described above.
[0018]
The ultrasonic pulse and the low coherence light are emitted from the distal end main body 102 toward the living body along the area 10 shown by the solid line in the figure. In the case of the present embodiment, the region 10 is a part of a plane including the longitudinal center axis A of the distal end portion main body 102. Thus, the distal end main body 102 can collect acoustic information and optical information for generating an ultrasonic tomographic image and an optical tomographic image along the region 10. From the collected optical information, it is possible to obtain an optical tomographic image near the surface of the living body indicated by a dotted line 12 in the figure, and from the acoustic information, an area located deeper in the living body than the optical tomographic image. Fourteen ultrasonic tomographic images can be obtained. Moreover, the obtained optical tomographic image and ultrasonic tomographic image are images that are continuous with each other at the boundary 16 irrespective of the position and the direction of the distal end main body 102.
[0019]
FIG. 2 is a plan view showing the vicinity of the distal end of the insertion portion flexible tube 100 shown in FIG. FIG. 3 is a partial cross-sectional view near the distal end of the flexible tube 100 of the insertion section shown in FIG.
[0020]
As shown in FIG. 3, an inclined surface 102b is formed near the rear side of the distal end portion main body 102. As shown in FIG. 2, three openings 150, 152, and 154 are formed in the slope 102b. The opening 150 is an outlet portion of a forceps channel for passing a treatment tool such as forceps. The opening 152 and the opening 154 are an outlet portion of an air supply nozzle for sending air and an outlet portion of a water supply nozzle for sending water, respectively.
[0021]
The slope 102b is further provided with an objective lens 156. The objective lens 156 is provided on the inclined surface 102b so as to form a subject image on a light receiving surface of a CCD (not shown) mounted in the distal end portion main body 102. Further, a light distribution lens 158 for irradiating illumination light toward a subject to be photographed by a CCD (not shown) is provided on the slope 102b.
[0022]
A curved side surface 102a is formed near the distal end of the distal end body 102. A plurality of ultrasonic transducers 110 are provided on the side surface 102a. These ultrasonic transducers 110 generate an ultrasonic pulse, irradiate it toward a living body, and detect an ultrasonic echo reflected from the living body. The plurality of ultrasonic transducers 110 are arranged in a line along a plane including the region 10 in FIG. 1, preferably at equal intervals. By arranging in this manner, the plurality of ultrasonic transducers 110 irradiate an ultrasonic pulse along the region 10 in FIG. It becomes possible to detect an ultrasonic echo containing information on the structure.
[0023]
A plurality of optical fibers 112 pass through the inside of the flexible tube 100 from the proximal end (not shown) to the distal end main body 102. Each optical fiber 112 is provided on the insertion portion flexible tube 100 to irradiate the low coherence light toward the living body from the distal end surface 114 and to receive the low coherent light reflected by the living body at the distal end surface 114. ing. The distal end surfaces 114 of the optical fibers 112 are arranged on the side surface 102a of the distal end main body 102 so as to be located between two adjacent ultrasonic transducers 110, preferably such that the distal end surfaces 114 are arranged at equal intervals. Have been. That is, on the side surface 102a of the distal end portion main body 102, the ultrasonic transducers 110 and the distal end surfaces 114 of the optical fibers are arranged in a line and alternately along a plane including the region 10 described above.
[0024]
The distal end surface 114 of the optical fiber 112 arranged as described above can irradiate the low-coherence light along the region 10 in FIG. Each optical fiber 112 can receive low coherence light including information indicating the structure of the living body near the surface (the area 12 in FIG. 1) without moving the distal end main body 102.
[0025]
A signal line 116 is connected to each ultrasonic transducer 110. The signal line 116 is wired to the endoscope main body (not shown) attached to the base end (not shown) of the insertion part flexible tube 100 through the inside of the insertion part flexible tube 100. Further, the signal line 116 is connected from the endoscope main body to an image processing device (not shown). Similarly, each optical fiber 112 passing through the insertion portion flexible tube 100 also extends to the endoscope main body (not shown), and is connected from the endoscope main body to the above-described image processing apparatus (not shown). Have been.
[0026]
The image processing apparatus (not shown) irradiates the living body with low-coherence light via each optical fiber 112 and receives the low-coherence light reflected on the living body via each optical fiber 112. Further, an image processing device (not shown) generates an optical tomographic image of the living body from the received low coherence light by applying optical coherence tomography. In the case of the present embodiment, the image processing apparatus generates an optical diagnostic image of a living body particularly corresponding to the region 12 in FIG. The image processing apparatus (not shown) supplies a drive signal for irradiating the living body with the ultrasonic pulse by the ultrasonic vibrator 110 to the signal line 116, and responds to the ultrasonic echo detected by the ultrasonic vibrator 110. The detection signal to be output is received via a signal line 116. Further, the image processing device generates an ultrasonic tomographic image of the living body based on the received detection signal. In the case of the present embodiment, the image processing apparatus generates an ultrasonic tomographic image of the living body particularly corresponding to the region 14 in FIG.
[0027]
Since the configuration and functions of such an image processing apparatus are described in detail in, for example, Japanese Patent Application Laid-Open No. 11-56752, detailed description thereof will be omitted in this specification.
[0028]
The insertion section flexible tube 100 of the endoscope according to one embodiment of the present invention has been described above. However, the insertion section flexible tube 100 can be modified into various forms. For example, in the flexible insertion tube 100 shown in FIG. 2, the plurality of ultrasonic transducers 110 and the tip surfaces 114 of the plurality of optical fibers are arranged in a line in the tip portion main body 102. As in the first modification shown in FIG. 4, the arrangement may be such that two rows 120 and 122 are formed.
[0029]
In this case, in the direction orthogonal to the arrangement direction (the direction parallel to the central axis A), the ultrasonic transducers (or the end faces of the optical fibers) of the first row 120 and the supersonic waves of the second row 122 The ultrasonic vibrator 110 and the optical fiber distal end surface 114 are arranged so that the ultrasonic vibrator (or the distal end surface of the optical fiber) does not adjoin, but rather the ultrasonic vibrator 110 and the distal end surface 114 of the optical fiber are adjacent to each other. Are desirably arranged. With this arrangement, for example, data detected by two ultrasonic transducers 110a and 110b adjacent to each other across one optical fiber 122a in the first row corresponds to the optical fiber 122a in the second row 122. It is possible to generate an ultrasonic tomographic image while supplementing with data detected by the ultrasonic transducer 110c disposed at the position where the ultrasonic tomographic image is located.
[0030]
Further, the ultrasonic transducer 110 and the distal end surface 114 of the optical fiber are arranged so that two rows 130 and 132 adjacent to each other are formed independently from each other as in a second modification illustrated in FIG. It may be. In this case, as shown in FIG. 6, the low coherent light 134 emitted from the optical fiber 112 passes through the ultrasonic sound field 136 emitted from the ultrasonic transducer 110 adjacent to the optical fiber 112. More preferably, it is preferable to adjust the direction of the distal end surface 114 so as to pass through the focus point 138 in the ultrasonic sound field 136 and to provide each optical fiber 112 to the distal end body 102.
[0031]
FIG. 7 is a view showing an insertion section flexible tube 200 which is a third modification of the insertion section flexible tube of the endoscope shown in FIG. FIG. 3 shows a partial cross-sectional view near the tip. FIG. 8 is a cross-sectional view of the flexible insertion tube 200 taken along the line II-II in FIG.
[0032]
The flexible insertion tube 200 of this modified example has a plurality of ultrasonic transducers 110 and a plurality of distal end surfaces 114 of optical fibers along the peripheral surface of a distal end body 202 attached to the distal end of the flexible insertion tube 200. It is different from the flexible tube 100 in FIG. By arranging the ultrasonic transducer 110 and the distal end surface 114 of the optical fiber in an annular shape, the flexible tube 200 irradiates the ultrasonic pulse and the low-interference light in a radial direction around the central axis A. In addition, a so-called radial scan can be performed. Therefore, if the flexible tube 200 is inserted into a body cavity such as the large intestine, an annular ultrasonic tomographic image and optical tomographic image of the body cavity can be obtained without rotating the distal end body 202.
[0033]
FIGS. 7 and 8 show a structure in which the distal end surface 114 of the optical fiber and the ultrasonic transducer 110 are arranged along different circumferences, respectively. The vibrator 110 may be arranged on the distal end body 202 so as to be alternately located along the same circumference.
[0034]
FIG. 9 is a view showing the vicinity of the distal end of the flexible insertion tube 300 as a further modification of the flexible flexible tube 200 shown in FIG. The cross section of the vicinity is shown. FIG. 10 is a sectional view of the flexible tube 300 along the line III-III in FIG.
[0035]
The insertion section flexible tube 300 of this modification is different from the insertion section flexible tube 200 shown in FIG. 7 in that a distal end main body 302 attached to the distal end thereof has a truncated conical mirror 304. . In the mirror 304, the side surface 306 is a reflecting surface that can reflect low-coherence light transmitted by the optical fiber 112.
[0036]
In the flexible tube 200 shown in FIG. 7, the distal end of each optical fiber 112 passed through the flexible tube is bent toward the outer peripheral surface of the flexible tube, and the distal end surface 114 of each optical fiber is bent. Is installed so as to face outward from the outer peripheral surface. On the other hand, in the flexible tube 300 of the insertion section of this modification, each optical fiber 112 emits low-coherence light toward the reflection surface 306 of the mirror without bending the tip end, and is substantially straight. The insertion portion is disposed inside the flexible tube 300. The emitted low coherence light is reflected on the reflecting surface 306 of the mirror in a radial direction about the center axis A of the distal end body 302, and furthermore, a light transmitting portion (such as an optical glass) provided in the probe 300. Irradiated to the outside of the probe 300 via a not-shown). This makes it possible to perform a substantial radial scan of low-coherence light.
[0037]
In the present modification in which the irradiation direction of the low coherence light is adjusted using the mirror 304 having the truncated cone shape as described above, since it is not necessary to perform the bending process on each end of the plurality of optical fibers 112, the insertion portion Flexible tubes can be manufactured more easily.
[0038]
【The invention's effect】
According to the present invention, acoustic information and optical information for generating an ultrasonic tomographic image and an optical tomographic image which are continuous with each other are reliably collected near the distal end of the flexible tube inserted into the body. An endoscope that can be provided can be provided.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external appearance near a distal end of an insertion portion flexible tube in an endoscope according to one embodiment of the present invention.
FIG. 2 is a plan view showing the vicinity of a distal end of the flexible tube of the insertion portion shown in FIG.
FIG. 3 is a partial cross-sectional view of the vicinity of a distal end of the flexible tube of the insertion portion shown in FIG. 2;
FIG. 4 is a view showing a first modification of the flexible tube of the insertion portion shown in FIG. 1;
FIG. 5 is a view showing a second modified example of the flexible tube of the insertion portion shown in FIG. 1;
FIG. 6 is a diagram illustrating the orientation of the distal end surface of the optical fiber in the flexible tube of the insertion section shown in FIG. 5;
FIG. 7 is a view showing a third modified example of the flexible tube of the insertion portion shown in FIG. 1;
8 is a cross-sectional view of the flexible tube of the insertion section taken along line II-II in FIG.
9 is a diagram showing a further modification of the flexible tube of the insertion portion shown in FIG. 7; FIG. 10 is a cross-sectional view of the flexible tube of the insertion portion along line III-III in FIG. 9;
[Explanation of symbols]
100, 200, 300 Flexible tube for insertion part 110 Ultrasonic transducer 112 Optical fiber 304 Frustoconical mirror

Claims (5)

It is inserted into the body to collect acoustic information for generating a tomographic image of a living body using ultrasound and optical information for generating a tomographic image of a living body using optical coherence tomography. An endoscope having an insertion portion flexible tube,
Along with irradiating an ultrasonic wave toward the living body to collect the acoustic information, a plurality of ultrasonic transmitting and receiving units that receive ultrasonic echoes generated in the living body,
The low-coherence light is irradiated toward the living body to collect the optical information, and a plurality of light entrances and exits that receive the low-coherence light reflected by the living body are provided at the distal end of the flexible tube. For the part,
The plurality of ultrasonic transmitting and receiving units are arranged so that the ultrasonic waves are irradiated along a predetermined ultrasonic irradiation surface,
An endoscope, wherein the plurality of light entrances and exits are arranged so that the low coherence light is irradiated along a predetermined light irradiation surface at least partially overlapping the ultrasonic irradiation surface. The endoscope according to claim 1, wherein the plurality of ultrasonic transmission / reception units and the plurality of light entrance / exit units are arranged substantially parallel to a longitudinal axis of the insertion unit flexible tube. . The endoscope according to claim 2, wherein the plurality of ultrasonic transmission / reception units and the plurality of light entrance / exit units are alternately arranged in a line. The said plurality of ultrasonic transmission / reception parts and the said several light-in / out parts are substantially annularly arranged along the circumferential direction of the front-end | tip part of the said insertion part flexible tube, The claim 1 characterized by the above-mentioned. Endoscope. A plurality of optical fibers for transmitting the low coherence light are arranged in a ring shape in the vicinity of the distal end of the insertion portion flexible tube,
The light entrance / exit portion includes a frusto-conical mirror that reflects the low coherence light emitted from each of the plurality of optical fibers in a radial direction around a central axis at a distal end portion of the insertion portion flexible tube. The endoscope according to claim 4, comprising:

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