JP4904142B2 - Medical diagnostic probe and medical diagnostic system - Google Patents

Description

  The present invention relates to a medical diagnostic probe for acquiring an image inserted into a subject and used for medical diagnosis of an observation site of the subject, and a medical diagnostic system using the same.

  In recent years, medical diagnosis using ultrasonic images has been put into practical use in the medical field. The ultrasonic image is obtained by irradiating the observation site of the subject with ultrasonic waves from the ultrasonic transducer arranged at the tip of the ultrasonic probe, and receiving the echo signal from the observation site with the ultrasonic transducer. It is obtained by electrically processing the output detection signal with a processor device.

  It is also possible to obtain an ultrasonic tomographic image by irradiating while scanning with ultrasonic waves. As a method for obtaining an ultrasonic tomographic image, a mechanical scanning scanning method in which an ultrasonic transducer is mechanically rotated, oscillated, or slid, or a plurality of ultrasonic transducers arranged in an array and driven is an electronic transducer. An electronic scan scanning method that is selectively switched by a switch or the like is known.

  The electronic scan scanning method includes a convex electronic scanning method in which a plurality of ultrasonic transducers are arranged in a fan shape at the probe tip. Ultrasonic probes using the convex electronic scanning method are mainly inserted into body cavities, such as the type that is inserted into the forceps opening of an electronic endoscope or the so-called ultrasonic endoscope integrated with an image sensor such as a CCD. Used. In particular, in an ultrasonic endoscope, using a treatment instrument such as a forceps, a puncture needle, or a high-frequency knife while observing an observation site with an ultrasonic tomographic image or an endoscope optical image obtained by an imaging device, Appropriate treatment can be performed on the affected area (see Patent Document 1).

  On the other hand, recently, a technique for obtaining an optical tomographic image of a site to be observed using an OCT (Optical Coherence Tomography) apparatus has attracted attention. In the OCT apparatus, a low-coherence light emitted from a light source such as an SLD (Super Luminescent Diode) is irradiated as a measurement light to the site to be observed, and the reflected light of the measurement light reflected from the site to be observed is combined with the reference light. The intensity of the interference light included in the wave light is measured, and an optical tomographic image is generated based on the measured intensity.

  In the case of an ultrasonic tomographic image, an image in a relatively wide range can be obtained from the surface of the observed site to a depth of several tens of millimeters. However, since the ultrasonic frequency band is several MHz to several tens of MHz, the resolution is several It is about 100 μm. On the other hand, in the case of an optical tomographic image, only an image with a depth of about several millimeters can be obtained from the surface of the observed site, but since it has a high resolution of about several μm, it is difficult to do early with an ultrasonic tomographic image. The discovery of cancer and the observation of atherosclerotic plaques are possible.

  In order to obtain an optical tomographic image with the configuration described in Patent Document 1, it is necessary to prepare a probe for optical tomographic image acquisition separately as a treatment tool. Therefore, it takes time to insert and remove the probe, and the probe is used. When there is, there is a problem that other treatment tools cannot be used and treatment cannot be performed.

Therefore, in order to obtain a tomographic image from a shallow depth portion near the surface of the observed site to a deeper depth portion, and to obtain a high resolution tomographic image in the shallow depth portion, There has been proposed a medical examination system in which an optical system such as an optical fiber and a lens for acquiring an optical tomographic image is arranged on a mechanical scanning radial scanning type ultrasonic probe (see Patent Document 2). In addition, an endoscope has been proposed in which a plurality of optical fibers are inserted and ultrasonic transducers and tip surfaces of optical fibers are alternately arranged so that at least part of the scanning surfaces of the ultrasonic waves and light overlap (patent) (Refer to Reference 3.)
JP-A-11-276422 Japanese Patent Laying-Open No. 2005-095624 Japanese Patent Laying-Open No. 2005-073433

  However, the invention described in Patent Document 2 is merely an example applied to a mechanical scanning radial scanning ultrasonic probe, and cannot be applied to a convex electronic scanning ultrasonic probe as it is. In addition, since only the optical tomographic image of the part perpendicular to the axial direction of the probe can be obtained, and the acquisition location of the ultrasonic tomographic image and the optical tomographic image is greatly shifted, diagnosis is performed by collating the two images. It was difficult to do.

  Furthermore, since the invention described in Patent Document 3 uses a plurality of optical fibers, there is a problem that the diameter of the optical fiber becomes thick and the burden on the patient increases. In addition, a control system for switching and driving a plurality of optical fibers and a processing system for generating an optical tomographic image by integrating reflected light from the plurality of optical fibers are required. There were concerns such as an increase in manufacturing costs.

  The present invention has been made in view of the above problems, and a tomographic image of a shallow depth portion near the surface of an observation site can be obtained as a high-resolution optical tomographic image. It is an object of the present invention to provide a medical diagnostic probe and a medical diagnostic system that can acquire an image with an ultrasonic tomographic image by an electronic scanning method.

  In order to achieve the above object, the invention according to claim 1 is a medical diagnostic probe for acquiring an image to be inserted into a subject and used for medical diagnosis of an observation site of the subject. A plurality of ultrasonic transducers arranged in an array, an ultrasonic tomographic image acquisition unit having an electronic scanning ultrasonic transducer array, and irradiating the observation site with measurement light, and from the observation site An optical system for receiving reflected light, and an optical tomographic image acquisition unit having a scanning mechanism that scans the measurement light onto the site to be observed.

  The ultrasonic transducer array is preferably driven by a convex electronic scanning method.

  The optical system is preferably provided so that a position at which the measurement light is emitted toward the site to be observed substantially coincides with the center of curvature of the curved surface.

  The scanning mechanism preferably scans the measurement light so as to be substantially parallel to the scanning direction of the ultrasonic waves. Alternatively, it is preferable that the scanning mechanism scans the measurement light so as to be substantially orthogonal to the scanning direction of the ultrasonic waves.

  The scanning mechanism preferably includes a MEMS mirror.

  Alternatively, the scanning mechanism preferably includes a motor. In this case, the motor is arranged at the base end portion, and the measurement light is scanned by rotating the optical fiber composing the optical system from the tip end portion to the base end portion by the motor. It is preferable to do. Moreover, it is preferable that the scanning mechanism includes a bevel gear that converts rotation by the motor into rotation with a direction orthogonal to the rotation axis as a rotation axis.

  Alternatively, the motor is disposed at the tip, and the optical member that emits the measurement light toward the site to be observed, which constitutes the optical system, is rotated by the motor to scan the measurement light. It is preferable to do. The distal end here refers to a portion that is connected to the distal end of the insertion portion that is inserted into the subject and is provided with an ultrasonic transducer array and an optical system. The proximal end portion refers to the distal end. Refers to the root of the insertion part opposite to the part.

  The optical tomographic image acquisition unit is preferably arranged on a side of the ultrasonic tomographic image acquisition unit. Alternatively, the ultrasonic tomographic image acquisition unit is divided into two with the ultrasonic transducer array being spaced apart at the center thereof, and the optical tomographic image acquisition unit is between the ultrasonic transducer arrays divided in two. It is preferable that it is arranged.

  It is preferable that a partition wall is provided between the ultrasonic tomographic image acquisition unit and the optical tomographic image acquisition unit.

  Alternatively, it is preferable that the ultrasonic tomographic image acquisition unit and the optical tomographic image acquisition unit are arranged close to each other. In this case, the optical tomographic image acquisition unit has an irradiation window that transmits the measurement light and the reflected light, and the irradiation window is provided to be shifted inside the surface on which the ultrasonic transducer array is arranged. Preferably it is.

  Alternatively, it is preferable that a member provided inside the surface on which the ultrasonic transducer array is disposed is formed of a material that transmits the measurement light and the reflected light, and is also used as an irradiation window of the optical tomographic image acquisition unit. .

  It is preferable that an endoscope optical image acquisition unit having an image pickup device for picking up an optical image of the observation site is provided. Moreover, it is preferable to provide a forceps channel through which the treatment tool is inserted.

  The invention according to claim 19 is a medical diagnostic system, wherein an ultrasonic tomographic image and an optical tomographic image are acquired using the medical diagnostic probe according to any one of claims 1 to 18. And

  According to the medical diagnostic probe and the medical diagnostic system of the present invention, since the electronic tomographic ultrasonic tomographic image acquisition unit and the optical tomographic image acquisition unit are provided, a shallow depth portion near the surface of the site to be observed is provided. A tomographic image can be acquired as a high-resolution optical tomographic image, and a tomographic image of a deep portion can be acquired as an electronic scanning ultrasonic tomographic image.

  In FIG. 1, a medical diagnostic system 2 according to the present invention includes a medical diagnostic probe 10, a processor device 11, a monitor 12, and the like. The medical diagnostic probe 10 includes an insertion portion 13 that is inserted into a subject, an operation portion 14 that is connected to a proximal end portion of the insertion portion 13, and a cord 15 that is connected to the processor device 11. . Various types of image acquisition units 20 to 22 (see FIG. 2 and FIG. 3) for acquiring an image of an observation site in the subject are built in the distal end portion 13a provided continuously with the distal end of the insertion portion 13. Yes. Images in the subject acquired by the various image acquisition units 20 to 22 are displayed on the monitor 12.

  A bending portion 13b connecting a plurality of bending pieces is provided behind the tip portion 13a. The bending portion 13b is bent in the vertical and horizontal directions when the angle knob 14a provided in the operation portion 14 is operated and a wire inserted in the insertion portion 13 is pushed and pulled. Thereby, the front-end | tip part 13a is orient | assigned to the desired direction in a subject.

  A flexible soft part 13c is provided behind the curved part 13b. The flexible portion 13c is a length for maintaining the distance from the patient so that the distal end portion 13a can reach the site to be observed and does not hinder the operator from gripping and operating the operation portion 14. Have Reference numeral 16 denotes a forceps port into which the treatment tool is inserted.

  2 and 3, the distal end portion 13a is provided with an endoscope optical image acquisition unit 20, an ultrasonic tomographic image acquisition unit 21, and an optical tomographic image acquisition unit 22. The endoscope optical image acquisition unit 20 includes an observation window 23, an objective lens 24, a CCD 25, an illumination window 26, a wiring cable 27, and the like.

  The observation window 23 is attached obliquely above the tip portion 13a. The image light of the site to be observed that has entered from the observation window 23 is imaged on the imaging surface of the CCD 25 by the objective lens 24. The CCD 25 photoelectrically converts the image light of the site to be observed that has passed through the observation window 23 and the objective lens 24 and is imaged on the imaging surface, and outputs an imaging signal. The imaging signal output from the CCD 25 is transmitted to the processor device 11 by the code 15 via the wiring cable 27 extended from the insertion unit 13 to the operation unit 14. The processor device 11 performs various signal processing and image processing on the transmitted imaging signal, and displays it on the monitor 12 as an endoscope optical image.

  The illumination window 26 is provided on both sides of the observation window 23. The illumination window 26 is connected to an emission end of a light guide (not shown). The light guide extends from the insertion unit 13 to the operation unit 14, and an incident end thereof is connected to a light source of a light source device (not shown) connected via a cord 15. Illumination light emitted from the light source travels through the light guide and is irradiated from the illumination window 26 to the site to be observed.

  The ultrasonic tomographic image acquisition unit 21 includes an ultrasonic transducer array 28. The ultrasonic transducer array 28 is provided on a backing material 29 having a convex arc shape in cross section. The backing material 29 is made of a material having rigidity such as hard rubber, and an ultrasonic attenuating material (ferrite, ceramics, etc.) is added as necessary. On the ultrasonic transducer array 28, an acoustic lens 30 made of silicon resin or the like and for converging the ultrasonic waves emitted from the ultrasonic transducer array 28 toward the site to be observed is attached.

  As an example, the ultrasonic transducer array 28 includes a plurality of ultrasonic transducers 31 arranged in a one-dimensional array at a predetermined pitch. The ultrasonic transducer 31 has a configuration in which electrodes are formed on both surfaces of a piezoelectric thick film such as PZT (lead zirconate titanate) or PVDF (polyvinylidene fluoride). One electrode is an electrode common to all the ultrasonic transducers 31, and the other electrode is an individual electrode independent for each ultrasonic transducer 31.

  When a voltage is applied to both electrodes, the piezoelectric body vibrates to generate ultrasonic waves, and thereby the ultrasonic waves are irradiated to the observation site of the subject. Then, by sequentially driving a plurality of ultrasonic transducers 31 with an electronic switch such as a multiplexer, ultrasonic waves are generated within a range of about several tens of millimeters from the center of curvature of the curved surface along the curved surface on which the ultrasonic transducer array 28 is arranged. Scanned. When an echo signal is received from the site to be observed, the piezoelectric body vibrates to generate a voltage, and this voltage is output as a detection signal. Although not shown in the figure, the gap between the ultrasonic transducers 31 is filled with a filler made of an epoxy resin, and an acoustic for relaxing acoustic impedance between the ultrasonic transducer 31 and the subject is provided on the ultrasonic transducer 31. A matching layer is provided.

  A flexible wiring substrate 33 is attached to the back surface of the backing material 29 via a substrate 32. The flexible wiring board 33 is connected to a wiring 34 connected to individual electrodes constituting the ultrasonic transducer 31. The wiring 34 extends from the insertion unit 13 to the operation unit 14 and is connected to the processor device 11 via the cord 15, similarly to the wiring cable 27 and the light guide. A drive control signal for driving the ultrasonic transducer 31 to emit an ultrasonic wave is transmitted from the processor device 11 through the wiring 34, and a detection signal output from the ultrasonic transducer 31 by receiving an echo signal is transmitted. It is transmitted to the processor unit 11. The processor device 11 performs various signal processing and image processing on the transmitted detection signal, and displays it on the monitor 12 as an ultrasonic tomographic image. In FIG. 3, hatching of the ultrasonic tomographic image acquisition unit 21 is omitted to avoid complication.

  The optical tomographic image acquisition unit 22 includes an optical fiber 35, a lens 36, a micro electro mechanical systems (MEMS) mirror 37, and the like. The optical fiber 35 extends from the insertion portion 13 to the operation portion 14 and is connected to a light source device (not shown) via the cord 15, similarly to the wiring cable 27, the light guide, and the wiring 34. The incident end of the optical fiber 35 is connected to a light source of a light source device that emits low-coherence light, whereby the measurement light L <b> 1 is emitted from the emission end of the optical fiber 35. The lens 36 condenses the measurement light L1 emitted from the optical fiber 35 and guides the reflected light L2 of the measurement light L1 reflected from the observation site to the optical fiber 35.

  The MEMS mirror 37 has a configuration in which a movable mirror 38 and a drive control board 39 are integrated. The movable mirror 38 is arranged near the center of curvature of the curved surface on which the ultrasonic transducer array 28 is arranged. The movable mirror 38 reflects the measurement light L1 collected by the lens 36 toward the site to be observed, and guides the reflected light L2 from the site to be observed to the lens 36. The movable mirror 38 rotates with a line parallel to the direction B perpendicular to the axial direction A of the insertion portion 13 as a rotation axis by a control signal from the drive control board 39. The drive control board 39 controls the rotation of the movable mirror 38 so that the scanning speed of the measurement light L1 is synchronized with the ultrasonic scanning speed. As a result, the measurement light L1 is scanned in the range of about several mm from the center of curvature of the curved surface (the range of the arrow C shown in FIG. 3) along the curved surface on which the ultrasonic transducer array 28 is disposed.

  The ultrasonic tomographic image acquisition unit 21 and the optical tomographic image acquisition unit 22 are separated by a partition wall 40 in order to prevent the vibration of the ultrasonic transducer 31 from affecting the operation of the optical tomographic image acquisition unit 22. An irradiation window 41 made of a material that transmits the measurement light L1 and the reflected light L2 is attached to the opposite side of the acoustic lens 30 across the partition wall 40.

  The reflected light L2 guided to the optical fiber 35 is combined with the reference light reflected by the reference light reflecting system by the fiber coupler of the light source device. The processor device 11 generates an optical tomographic image based on the measurement result of the intensity of the interference light included in the combined light and displays it on the monitor 12.

  A forceps outlet 42 is provided between the endoscope optical image acquisition unit 20 and the ultrasonic tomographic image acquisition unit 21. A forceps channel 43 provided through the insertion portion 13 from the forceps opening 16 communicates with the forceps outlet 42, and a distal end of a treatment instrument such as a forceps, a puncture needle, or a high-frequency knife protrudes from the forceps outlet 42. Is done.

  Next, the operation of the medical diagnostic probe 10 having the above configuration will be described. First, the insertion unit 13 is inserted into the subject, and the observation site is searched while observing the endoscope optical image acquired by the endoscope optical image acquisition unit 20 on the monitor 12.

  When the distal end portion 13 a reaches the site to be observed and an instruction to acquire an ultrasonic tomographic image is given, a drive control signal from the processor device 11 is input to the ultrasonic transducer 31 via the wiring 34. When the drive control signal is input, a prescribed voltage is applied to both electrodes of the ultrasonic transducer 31. Then, the piezoelectric body of the ultrasonic transducer 31 is excited, and ultrasonic waves are emitted to the site to be observed via the acoustic lens 30.

  After the ultrasonic irradiation, an echo signal from the site to be observed is received by the ultrasonic transducer 31. The irradiation of the ultrasonic wave and the reception of the echo signal are repeatedly performed while the driving ultrasonic transducer 31 is shifted by an electronic switch such as a multiplexer. Thereby, an ultrasonic wave is scanned to the site to be observed. Then, the processor device 11 generates an ultrasonic tomographic image based on the detection signal output from the ultrasonic transducer 31 upon receiving the echo signal. The generated ultrasonic tomographic image is displayed on the monitor 12.

  On the other hand, when an instruction to acquire an optical tomographic image is given, low-coherence light is emitted from the light source of the light source device. The emitted low coherence light is branched into the measurement light L1 traveling to the optical fiber 35 and the reference light.

  The measurement light L1 directed toward the optical fiber 35 is emitted from the emission end of the optical fiber 35, is condensed by the lens 36, is reflected by the movable mirror 38, and is irradiated onto the site to be observed through the irradiation window 41. The reflected light L <b> 2 reflected at a predetermined depth of the site to be observed is guided to the optical fiber 35 through the movable mirror 38 and the lens 36. The reflected light L2 guided to the optical fiber 35 is returned to the light source device through the optical fiber 35 again. On the other hand, the reference light is reflected by the reference light reflection system and then multiplexed by the reflected light L2 guided to the optical fiber 35 by the fiber coupler.

  If the optical path length until the reflected light L2 reaches the fiber coupler after the low coherence light is split into the measurement light L1 and the reference light is equal to the optical path length until the reference light reaches the fiber coupler Interfere.

  Then, the processor device 11 detects the intensity of the interference light from the combined light of the reflected light L2 and the reference light. The detection of the intensity of the interference light is performed while changing the optical path length until the reference light reaches the fiber coupler, whereby tomographic information from the surface of the observed site to a desired depth is acquired.

  When the series of detections at the observation site is completed, the movable mirror 38 is slightly rotated about the line parallel to the direction B by the drive control board 39, and a predetermined point at a point slightly shifted from the first observation site is obtained. Fault information up to the depth is acquired by the same procedure as described above. In this way, the tomographic information in the desired scanning range is acquired while the minute movement by the movable mirror 38 is repeated. Then, the processor device 11 generates an optical tomographic image based on the detection result of the intensity of the interference light. The generated optical tomographic image is displayed on the monitor 12.

  As described above, while an endoscopic optical image, an ultrasonic tomographic image, or an optical tomographic image is observed on the monitor 12, a treatment tool is inserted into the forceps port 16 as necessary, and an appropriate treatment such as a biopsy is performed. Applied.

  As described above, the medical diagnostic probe 10 acquires an ultrasonic tomographic image of a surface having a depth of about several tens of millimeters substantially parallel to the axial direction A of the insertion portion 13 by a convex electronic scanning method. Since the image acquisition unit 21 and the optical tomographic image acquisition unit 22 that acquires an optical tomographic image having a depth of about several millimeters are provided, the ultrasonic tomographic image and the optical tomographic image can be acquired seamlessly. . For this reason, it is not necessary to place a burden on the patient, such as replacing the probe by inserting and removing the probe one by one.

  In addition, when observing a deep part of the observed region, an ultrasonic tomographic image that covers a wide range with a low resolution can be obtained using the ultrasonic tomographic image acquisition unit 21. When observing a shallow portion, a high-resolution optical tomographic image can be obtained using the optical tomographic image acquisition unit 22. Therefore, a tomographic image corresponding to the purpose of diagnosis can be acquired quickly.

  Conventionally, in order to obtain an optical tomographic image, a probe for acquiring an optical tomographic image is inserted into the forceps port 16 to make a diagnosis, so there is a problem that treatment cannot be performed with another treatment tool. However, since the forceps channel 43 is vacant, various treatments can be performed freely.

  Furthermore, a movable mirror 38 is arranged near the center of curvature of the curved surface on which the ultrasonic transducer array 28 is arranged so that the centers of the ultrasonic tomographic image and the optical tomographic image substantially coincide with each other. And a more detailed and comprehensive diagnosis with reference to both images can be performed.

  In the above embodiment, the ultrasonic tomographic image acquisition unit 21 and the optical tomographic image acquisition unit 22 are separated by the partition wall 40. However, as shown in FIG. 21 and the optical tomographic image acquisition unit 22 may be arranged close to each other. In this way, the area of the ultrasonic transducer array 28 can be increased by the space taken by the partition wall 40, and the ultrasonic scanning range can be widened. Moreover, the acquisition location of an ultrasonic tomographic image and an optical tomographic image can be brought closer.

  In the above case, in order to prevent the vibration of the ultrasonic transducer 31 from affecting the operation of the optical tomographic image acquisition unit 22, the irradiation window 41 is substantially the same as the acoustic lens 30 as shown in FIGS. 5 and 6. It is preferable to dispose not the position of the surface but the position inside the backing material 29 or the side of the substrate 32 inside.

  Further, as shown in FIG. 7, the substrate 32 is formed of a material that transmits the measurement light L <b> 1 and the reflected light L <b> 2, is extended to the side so as to cover the optical tomographic image acquisition unit 22, and is also used as the irradiation window 41. It is good also as a structure. In this way, the number of parts and the number of assembly steps can be reduced.

  In the above embodiment, the optical tomographic image acquisition unit 22 is arranged on the side of the ultrasonic tomographic image acquisition unit 21, but the present invention is not limited to this, and as shown in FIG. The transducer array 28 may be divided into two at the center, and the optical tomographic image acquisition unit 22 may be disposed therebetween. In this way, it is possible to acquire an ultrasonic tomographic image and an optical tomographic image in a plane perpendicular to the axial direction A that passes through the center of curvature of the curved surface on which the ultrasonic transducer array 28 is disposed. Becomes easier. In FIG. 8, the ultrasonic tomographic image acquisition unit 21 and the optical tomographic image acquisition unit 22 are arranged close to each other as in the examples illustrated in FIGS. 4 to 7. Similarly to the example shown, a partition may be provided between the ultrasonic tomographic image acquisition unit 21 and the optical tomographic image acquisition unit 22 to separate them.

  In the above embodiment, the measurement light L1 is scanned using the MEMS mirror 37. However, as shown in FIG. 9, a motor 50 is disposed at the base end of the operation unit 14 or the like, and the motor 50 is driven to rotate. It may be used to scan the measurement light L1.

  The motor 50 is connected to the optical fiber 35 and rotationally drives the optical fiber 35 about a line parallel to the axial direction A as a rotation axis. A bevel gear 52 that is rotatably fitted to the bearing 51 is attached to the exit end of the optical fiber 35, and a mirror 53 that reflects light at a right angle is provided at the end of the exit end of the optical fiber 35. . A bevel gear 55 that is rotatably fitted to the bearing 54 and meshes with the bevel gear 52 is attached at a position perpendicular to the bevel gear 52 with the mirror 53 interposed therebetween. The bevel gear 55 has a hole 56 that transmits light. A GRIN (Great Index) lens 57 that refracts light in a parabolic shape is attached to the root portion of the bevel gear 55, and a prism mirror 58 that reflects light at a right angle is attached to the GRIN lens 57. It is attached.

  The measurement light L1 emitted from the optical fiber 35 is reflected by the mirror 53 in parallel with the direction B, passes through the hole 56 of the bevel gear 55, and enters the GRIN lens 57. The measurement light L1 incident on the GRIN lens 57 is refracted into a parabolic shape by the GRIN lens 57 to be parallel light, is reflected at a right angle by the prism mirror 58, and is irradiated to the observation site through the irradiation window 41. The reflected light L <b> 2 reflected at the site to be observed follows the optical path opposite to that of the measuring light L <b> 1 and is guided to the optical fiber 35.

  When the optical fiber 35 is rotationally driven by the motor 50 using a line parallel to the axial direction A as a rotation axis, the bevel gear 55 meshed with the bevel gear 52 is rotated using a line parallel to the direction B as a rotation axis. Along with this, the GRIN lens 57 and the prism mirror 58 attached to the bevel gear 55 are rotated, and the measurement light L1 is scanned over the site to be observed.

  As described above, if the rotation of the optical fiber 35 with the line parallel to the axial direction A by the motor 50 as the rotation axis is converted into the rotation with the line parallel to the direction B at the bevel gears 52 and 55, The measurement light L1 can be scanned with a simple structure so as to be substantially parallel to the ultrasonic scanning direction.

  Further, as shown in FIG. 10, a small motor 60 such as an ultrasonic motor may be disposed at the tip end portion 13 a and the measurement light L <b> 1 may be scanned using the rotational drive of the motor 60. The motor 60 is connected to a mirror 61 corresponding to the optical member according to the ninth aspect, and rotationally drives the mirror 61 about a line parallel to the direction B as a rotation axis. A GRIN lens 62 is attached to the emission end of the optical fiber 35, and a prism mirror 63 that reflects light at a right angle is attached to the GRIN lens 62.

  The measurement light L1 emitted from the optical fiber 35 is refracted into a parabolic shape by the GRIN lens 62 to become parallel light, and is reflected by the prism mirror 63 at a right angle in the B direction. The measurement light L <b> 1 reflected by the prism mirror 63 is reflected by the mirror 61 and is irradiated to the observation site via the irradiation window 41. The reflected light L <b> 2 reflected at the site to be observed follows the optical path opposite to that of the measuring light L <b> 1 and is guided to the optical fiber 35. The motor 60 rotates the mirror 61 about a line parallel to the direction B as a rotation axis, and thereby the measurement light L1 is scanned over the site to be observed.

  In the case of the system shown in FIG. 10, since the bevel gears 52 and 55 for converting the rotation are not required as in the system shown in FIG. 9, the number of parts and the number of assembling steps are reduced, and the scanning of the measuring light L1 is smoother. Can be done. For this reason, it is preferable to employ the system shown in FIG. 9 when there is no space for disposing the motor 60 at the distal end portion 13a, and the system shown in FIG. 10 when there is a space.

  In the above-described embodiment, the example in which the measurement light L1 is scanned so as to be substantially parallel to the ultrasonic scanning direction has been described. However, even if the measurement light L1 is scanned so as to be substantially orthogonal to the ultrasonic scanning direction. Good. In this case, for example, as shown in FIG. 11, which is a modification of the system shown in FIG. 8, the ultrasonic transducer array 28 is divided into two along the direction B, and the optical tomographic image acquisition unit 22 is arranged therebetween. Further, unlike the above embodiment, the irradiation window 41 is arranged to be parallel to the direction B. Then, the movable mirror 38 is driven to rotate about the axial direction A as the rotation axis.

  It is described that all the image acquisition units 20 to 22 are connected to the processor device 11 and each image is generated only by the processor device 11. However, a dedicated processor device may be prepared separately. Good. Similarly, each image is displayed on the monitor 12, but a dedicated monitor may be prepared separately. Further, although the display form of each image is not particularly mentioned, it can be changed as appropriate, such as switching each image to display it individually, displaying each image in a superimposed manner, or dividing the screen. Is possible.

  In the above embodiment, the intensity distribution of reflected light corresponding to the position in the depth direction of the site to be observed is acquired by measuring the interference light intensity while changing the optical path length of the reference light, so-called TD (Time Domain). Although the system OCT (TD-OCT) has been described as an example, the present invention is not limited to this, and other systems, for example, an FD (Fourier Domain) system OCT (FD-OCT) may be adopted. .

  The FD-OCT measures the interference light intensity for each spectral component of light without changing the optical path lengths of the measurement light and the reference light. Then, the spectrum interference intensity signal thus obtained is subjected to frequency analysis represented by Fourier transform by a computer, thereby obtaining a reflected light intensity distribution corresponding to the position in the depth direction of the site to be observed. Since FD-OCT does not require the operation of changing the optical path lengths of the measurement light and the reference light, which is essential in TD-OCT, high-speed measurement is possible.

  As typical examples of the FD-OCT apparatus configuration, there are two types of SD (Spectral Domain) -OCT and SS (Swept Source) -OCT. SD-OCT uses broadband low-coherent light such as SLD, ASE (Amplified Spontaneous Emission) light source, and white light as a light source. Using a Michelson interferometer or the like, broadband low-coherent light is divided into measurement light and reference light, and then the measurement light is irradiated onto the site to be observed, and reflected light and reference light at that time interfere with each other. Then, the interference light is decomposed into frequency components by a spectrometer, and the interference light intensity of each frequency component is measured using a detector array in which elements such as photodiodes are arranged in an array. An optical tomographic image is generated by Fourier-transforming the spectral interference intensity signal obtained by this measurement with a computer.

  SS-OCT uses, as a light source, a laser that temporally sweeps the optical frequency. The reflected light and the reference light are caused to interfere at each wavelength, and the time waveform of the signal corresponding to the time change of the optical frequency is measured. Then, an optical tomographic image is generated by Fourier-transforming the spectral interference intensity signal thus obtained by a computer.

  The present invention is not limited to the convex electronic scanning method exemplified in the above embodiment, and a plano-concave (plano-concave) electron in which an ultrasonic transducer is formed so as to have a non-uniform thickness with respect to the axial direction of the insertion portion. The scanning method can also be applied.

It is the schematic which shows the structure of the medical diagnostic system of this invention. It is an enlarged plan view which shows the front-end | tip part vicinity of the probe for medical diagnosis of this invention. It is an expanded sectional view showing the tip part vicinity of the probe for medical diagnosis of the present invention. It is an enlarged plan view which shows the example which has arrange | positioned the ultrasonic tomographic image acquisition part and the optical tomographic image acquisition part closely. It is an expanded sectional view which shows the front-end | tip part vicinity of the example shown in FIG. It is an expanded sectional view which shows the front-end | tip part vicinity of the example shown in FIG. It is an enlarged plan view which shows the example which used the board | substrate also as the irradiation window. FIG. 6 is an enlarged plan view showing an example in which an ultrasonic transducer array is divided and an optical tomographic image acquisition unit is arranged between them. It is an enlarged plan view which shows the example which scans measurement light using a motor and a bevel gear. It is an enlarged plan view which shows the example which scans measurement light using a motor. It is an enlarged plan view showing an example of scanning measurement light so as to be substantially orthogonal to the scanning direction of ultrasonic waves.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Medical diagnostic system 10 Medical diagnostic probe 13a Tip part 20 Endoscopic optical image acquisition part 21 Ultrasonic tomographic image acquisition part 22 Optical tomographic image acquisition part 25 CCD
28 Ultrasonic transducer array 31 Ultrasonic transducer 32 Substrate 35 Optical fiber 37 MEMS mirror 40 Bulkhead 41 Irradiation window 43 Forceps channel 50, 60 Motor 52, 55 Bevel gear 61 Mirror

Claims (18)

A medical diagnostic probe for acquiring an image inserted into a subject and used for medical diagnosis of an observation site of the subject,
An ultrasonic tomographic image acquisition unit having an electronic scanning ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged in an array on a curved surface;
An optical tomographic image acquisition unit having an optical system for irradiating the observation site with measurement light and receiving reflected light from the observation site, and a scanning mechanism for scanning the measurement light on the observation site; equipped with a,
A medical diagnostic probe, wherein a partition wall is provided between the ultrasonic tomographic image acquisition unit and the optical tomographic image acquisition unit .   The medical diagnostic probe according to claim 1, wherein the ultrasonic transducer array is driven by a convex electronic scanning method.   The medical system according to claim 1 or 2, wherein the optical system is provided so that a position at which the measurement light is emitted toward the site to be observed substantially coincides with a center of curvature of the curved surface. Diagnostic probe.   The medical diagnostic probe according to claim 1, wherein the scanning mechanism scans the measurement light so as to be substantially parallel to a scanning direction of the ultrasonic wave.   The medical diagnostic probe according to any one of claims 1 to 3, wherein the scanning mechanism scans the measurement light so as to be substantially orthogonal to a scanning direction of the ultrasonic waves.   6. The medical diagnostic probe according to claim 1, wherein the scanning mechanism includes a MEMS type mirror.   The medical diagnostic probe according to claim 1, wherein the scanning mechanism includes a motor. The motor is arranged at the base end,
The medical diagnostic scan according to claim 7, wherein the measurement light is scanned by rotating an optical fiber constituting the optical system, which is communicated from a distal end portion to the proximal end portion, by the motor. probe.   The medical diagnostic probe according to claim 7 or 8, wherein the scanning mechanism includes a bevel gear that converts rotation by the motor into rotation with a direction orthogonal to the rotation axis as a rotation axis. The motor is arranged at the tip,
The medical device according to claim 7, wherein the measurement light is scanned by rotating an optical member that constitutes the optical system and emits the measurement light toward the site to be observed by the motor. Diagnostic probe.   The medical diagnostic probe according to any one of claims 1 to 10, wherein the optical tomographic image acquisition unit is arranged on a side of the ultrasonic tomographic image acquisition unit. In the ultrasonic tomographic image acquisition unit, the ultrasonic transducer array is divided into two with a gap in the center,
The medical diagnostic probe according to any one of claims 1 to 10, wherein the optical tomographic image acquisition unit is disposed between the two ultrasonic transducer arrays. The medical diagnostic probe according to any one of claims 1 to 12 , further comprising an endoscope optical image acquisition unit having an imaging element that captures an optical image of the observation site. The medical diagnostic probe according to any one of claims 1 to 13 , further comprising a forceps channel through which the treatment tool is inserted. Medical diagnostic system characterized by using medical diagnostic probe according to any one of claims 1 to 14, and acquires an ultrasonic tomographic image and the optical tomographic image. A medical diagnostic probe for acquiring an image inserted into a subject and used for medical diagnosis of an observation site of the subject,
An ultrasonic tomographic image acquisition unit having an electronic scanning ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged in an array on a curved surface;
An optical tomographic image acquisition unit having an optical system for irradiating the observation site with measurement light and receiving reflected light from the observation site, and a scanning mechanism for scanning the measurement light on the observation site; With
The medical diagnostic probe, wherein the scanning mechanism scans the measurement light so as to be substantially orthogonal to a scanning direction of the ultrasonic waves. A medical diagnostic probe for acquiring an image inserted into a subject and used for medical diagnosis of an observation site of the subject,
An ultrasonic tomographic image acquisition unit having an electronic scanning ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged in an array on a curved surface;
An optical tomographic image acquisition unit having an optical system for irradiating the observation site with measurement light and receiving reflected light from the observation site, and a scanning mechanism for scanning the measurement light on the observation site; With
The ultrasonic tomographic image acquisition unit and the optical tomographic image acquisition unit are arranged close to each other,
The optical tomographic image acquisition unit has an irradiation window that transmits the measurement light and the reflected light,
The medical diagnostic probe according to claim 1, wherein the irradiation window is provided so as to be shifted inside a surface on which the ultrasonic transducer array is arranged. A medical diagnostic probe for acquiring an image inserted into a subject and used for medical diagnosis of an observation site of the subject,
An ultrasonic tomographic image acquisition unit having an electronic scanning ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged in an array on a curved surface;
An optical tomographic image acquisition unit having an optical system for irradiating the observation site with measurement light and receiving reflected light from the observation site, and a scanning mechanism for scanning the measurement light on the observation site; With
The ultrasonic tomographic image acquisition unit and the optical tomographic image acquisition unit are arranged close to each other,
A member provided inside the surface on which the ultrasonic transducer array is disposed is formed of a material that transmits the measurement light and the reflected light, and is also used as an irradiation window of the optical tomographic image acquisition unit. Medical diagnostic probe.

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