JP2011104239A - Scanning medical probe and medical observation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scanning medical probe which is constitutively suitable for taking images from viewpoints of both direct-viewing observation images and side-viewing observation images. <P>SOLUTION: The scanning medical probe has a first optical fiber which transmits light emitted from a light source to an object, vibration means which vibrates the first optical fiber so that an emission end of the first optical fiber orbits a prescribed rotational trajectory, a direct-viewing objective optical system which condenses light emitted from the emission end onto the object and faces in a longitudinal direction of the scanning medical probe, a side-viewing objective optical system which faces in a direction perpendicular to the direct-viewing objective optical system, and a second optical fiber which transmits a reflection of the light condensed on the object to a prescribed outer device. The scanning medical probe is constituted to vibrate a neighborhood of the emission end so that light emitted from the emission end of the first optical fiber may alternatively enter the direct-viewing objective optical system or the diagonal-viewing objective optical system. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a scanning medical probe that scans light emitted from a light source on an object. Specifically, the object is optically scanned by resonating the tip of an ultrafine optical fiber to obtain image information. The present invention relates to a scanning medical probe to be acquired. The present invention also relates to a medical observation system having the medical probe.

  An electronic scope is generally known as a medical device used when a doctor observes the inside of a body cavity of a patient. A doctor who uses the electronic scope inserts the insertion portion of the electronic scope into the body cavity and guides the distal end portion provided at the distal end of the insertion portion to the vicinity of the observation target. A doctor operates an operation unit of an electronic scope or a video processor as necessary in order to photograph a living tissue in a body cavity with a solid-state imaging device such as a CCD (Charge Coupled Device) mounted on a distal end portion. A doctor observes an image of a living tissue obtained as a result of various operations through a monitor, and performs examinations and treatments.

  As described above, the electronic scope is used by being inserted into a body cavity of a patient. Therefore, regarding electronic scopes, there is a constant demand for reducing the diameter of the insertion portion in order to reduce the burden on the patient. In order to reduce the diameter of the electronic scope, it is desired to reduce the size of various built-in components themselves in addition to devising the arrangement of various built-in components. Note that the solid-state imaging device and the objective optical system have large dimensions among the built-in components of the electronic scope, and the ratio of exclusive use of the component mounting space inside the distal end portion of the electronic scope is high. According to another aspect, the minimum outer diameter dimension that can be designed in the electronic scope is substantially defined by the dimensions of the solid-state imaging device and the objective optical system.

  By the way, among electronic scopes, there is a type configured to be able to capture images of both viewpoints of a direct-view observation image and a side-view observation image. Specific configuration examples of this type of electronic scope are described in Patent Documents 1 to 4 and the like. According to each literature of patent documents 1-4, the solid-state image sensor or the objective optical system is separately arrange | positioned in the front-end | tip part of an electronic scope for direct view and side view. Therefore, it is regarded as a problem that the diameter of the electronic scope cannot be avoided.

  Here, a scanning medical probe that can be made smaller in diameter than a conventional electronic scope (that is, an electronic scope equipped with a solid-state imaging device) by adopting a configuration that does not require the solid-state imaging device itself is provided. Proposed. A specific configuration example of a medical observation system having this type of scanning medical probe is described in Patent Document 5. The scanning medical probe described in Patent Document 5 resonates the tip of a single optical fiber and scans an object with a predetermined scanning pattern using predetermined scanning light. Such a scanning medical probe detects reflected light from an object, photoelectrically converts it, and sequentially outputs it to a video processor. The video processor processes the photoelectrically converted signal, images it, and outputs it to the monitor. The doctor can observe the image in the body cavity obtained in this way through a monitor in the same manner as when using an electronic scope, and can perform examinations and treatments.

JP-A-11-137512 JP-A-11-253401 JP 2004-329699 A JP 2005-455 A US Pat. No. 6,563,105

  The problem of the increase in the diameter of the electronic scope described in Patent Documents 1 to 4 is a configuration in which the scanning medical probe described in Patent Document 5 is applied. It is considered that the problem can be solved by providing a medical observation device that can capture images of both viewpoints of the observation image. However, so far, there has been no mention of the configuration of such a medical observation system, and no problem has been raised about the medical observation system, and there are no means for solving the problem. No consideration has been given.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a scanning medical probe having a configuration suitable for capturing images of both the direct-view observation image and the side-view observation image. And a medical observation system having the scanning medical probe having the above configuration.

  A scanning medical probe according to an embodiment of the present invention that solves the above problems is a medical observation device that scans light irradiated from a light source on an object, and is configured as follows. That is, in the scanning medical probe according to the present invention, the first optical fiber that transmits the light emitted from the light source toward the object and the emission end of the first optical fiber draw a predetermined rotation locus. And an objective optical system for condensing the light emitted from the exit end onto the object, which is oriented in the long axis direction of the scanning medical probe A direct-view objective optical system; a side-view objective optical system oriented in a direction orthogonal to the direct-view objective optical system; and a second that transmits reflected light of the light collected on the object to a predetermined external device. Optical fiber. The vibration means scans the scanning light with respect to both the direct-view object and the side-view object, and obtains image information of the viewpoints of both the direct-view observation image and the side-view observation image. The vicinity of the emission end is vibrated so that light emitted from the emission end selectively enters the direct-view objective optical system or the perspective objective optical system.

  The scanning medical probe according to the present invention further includes a wall portion that divides a space in front of the exit end of the first optical fiber into two spaces, and each of the divided spaces has a direct-view objective optical system, A side-view objective optical system may be disposed. The surface of the wall that faces the exit end of the first optical fiber is exposed to an unwanted scattering component incident on the objective optical system that is not intended and the exit end of the specular reflection component on the surface. In order to avoid the incidence to the light, a material having a high light absorptance with respect to the light having the wavelength used may be applied.

  The wall portion may be a mirror portion included in the side-view objective optical system for bending light incident on the side-view objective optical system to be emitted to the side of the scanning medical probe.

  Here, the vibration means may rotate the emission end around a predetermined rotation reference position during a light emission period in which light is emitted from the emission end of the first optical fiber, or the emission end. May be rotated around the rotation reference position while shifting a predetermined rotation reference position.

  The scanning medical probe according to the present invention includes a forceps raising base for raising a forceps, and a first objective optical system for direct viewing and a side viewing objective optical system in conjunction with the raising action of the forceps raising base. Reference position shifting means for shifting the rotation reference position of the exit end of the optical fiber may be further included. The reference position shift means may be configured to shift the rotation reference position of the exit end of the first optical fiber to the side viewing objective optical system side.

  A medical observation system according to an aspect of the present invention that solves the above problems includes a light source that causes light to enter a first optical fiber, the scanning medical probe according to any one of the above, and a second light. An image signal detecting means for detecting an image signal by receiving light transmitted by a fiber, and assigning a pixel address of a direct-view image to the image signal detected at the first timing, and a second different from the first timing A pixel arrangement determining means for allocating a pixel address of a side-view image to the image signal detected at the timing and determining a pixel arrangement of image information represented by the image signal; and a pixel determined by the pixel arrangement determining means An image creation means for creating an image by spatially arranging each piece of image information according to the arrangement.

  ADVANTAGE OF THE INVENTION According to this invention, the scanning medical probe of the structure suitable for image | photographing the viewpoint image of both a direct-viewing observation image and a side-viewing observation image, and a medical observation system which has a scanning medical probe of this structure Is provided.

It is a block diagram which shows typically the internal structure of the scanning medical probe of 1st embodiment of this invention, and a one part structure of a processor. It is a block diagram which shows the structure of the processor and monitor of 1st embodiment of this invention. It is a front view which shows typically the structure of the insertion part front-end | tip of the scanning medical probe of 1st embodiment of this invention. It is a figure which shows typically the internal structure of the insertion part front-end | tip of the scanning medical probe of 1st embodiment of this invention. It is a figure which shows the emission position of each combined pulse light at the time of the piezoelectric actuator drive of the scanning medical probe of 1st embodiment of this invention. It is a figure for demonstrating the spot formed on the observation object in 1st embodiment of this invention. It is a block diagram which shows the structure of DSP which the processor of 1st embodiment of this invention has. It is a figure which shows an example of the direct view image and side view image which are displayed on a monitor in 1st embodiment of this invention. It is a figure which shows typically the internal structure of the insertion part front-end | tip of the scanning medical probe of 2nd embodiment of this invention. It is a figure for demonstrating the positional relationship of each electrode of the piezoelectric actuator which the scanning medical probe of 3rd embodiment of this invention has. In 3rd embodiment of this invention, it is a figure for demonstrating the relationship between the rotation locus | trajectory of the exit end of the single mode fiber on a XY approximate surface, and pixel arrangement | positioning. It is a figure which shows typically the internal structure of the insertion part front-end | tip of the scanning medical probe of 4th embodiment of this invention.

  Hereinafter, a medical observation system having a scanning medical probe according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram schematically showing an internal configuration of a scanning medical probe 100 and a partial configuration of a processor 200 according to the first embodiment of the present invention. FIG. 2 is a block diagram illustrating configurations of the processor 200 and the monitor 300 according to the first embodiment. In FIG. 2, in order to clarify the connection relationship between the scanning medical probe 100 and the processor 200, a part of the configuration of the scanning medical probe 100 is also schematically shown. Further, since the monitor 300 is an image receiving apparatus having a known configuration, the detailed configuration of the monitor 300 is not shown in FIG. As shown in these drawings, the medical observation system 1 of the first embodiment includes a scanning medical probe 100, a processor 200, and a monitor 300.

  The processor 200 controls the driving of the scanning medical probe 100 and generates an image signal based on the observation light acquired by the scanning medical probe 100, and the scanning medical medical device in a body cavity where natural light does not reach. The integrated processor includes a light source device that emits scanning light through the probe 100. In another embodiment, the signal processing device and the light source device may be configured separately.

  As shown in FIG. 2, the scanning medical probe 100 has an optical connector portion 110 and an electrical connector portion 120 at the proximal end portion. Further, the processor 200 includes an optical connector unit 210 and an electrical connector unit 220. By inserting the optical connector part 110 into the optical connector part 210, the scanning medical probe 100 and the processor 200 are optically connected. Similarly, when the electrical connector unit 120 is inserted into the electrical connector unit 220, the scanning medical probe 100 and the processor 200 are electrically connected. The processor 200 and the monitor 300 are electrically connected via a predetermined cable. In FIG. 1, in order to make it easy to understand the connection relationship between the scanning medical probe 100 and the processor 200, the connection portion between the optical connector portions 110 and 210 is divided into two.

  Thus, when the scanning medical probe 100, the processor 200, and the monitor 300 are connected to each other and the power is turned on, the operator can use the medical observation system 1 to examine and perform treatment in the body cavity of the patient. It becomes like this. Specifically, the operator needs the operation panel 260 of the processor 200 while inserting the insertion portion 130 of the scanning medical probe 100 into the body cavity and guiding the insertion portion distal end 130a of the insertion portion 130 to the vicinity of the observation target. Depending on the operation. The surgeon observes an image of a living tissue in the body cavity obtained as a result of such an operation through the monitor 300, and performs an examination or a treatment.

  In the first embodiment, the scanning medical probe 100 alone is directly inserted into the body cavity in order to observe the living tissue in the body cavity. In another embodiment, for example, in order to smoothly guide the insertion portion distal end 130a to the vicinity of the observation target, the insertion portion 130 may be inserted with a guide wire or the like. Further, for example, the insertion portion 130 may be inserted through a forceps channel of an electronic scope or the like so that the insertion portion distal end 130a is close to the vicinity of the observation target.

  The processor 200 includes laser light sources 230R, 230G, and 230B that oscillate light corresponding to wavelengths of R, G, and B as light sources for scanning the observation target. These three laser light sources may be replaced with, for example, a single fiber laser that oscillates a broadband supercontinuum light or the like. Further, the light source is not limited to the laser light source, and may be a light source of another form such as an LED (Light Emitting Diode).

  The processor 200 includes a system controller 240 that comprehensively controls signal processing timing and the like of each circuit of the processor 200. The system controller 240 outputs predetermined modulation control signals to the driver circuits of the drivers 232R, 232G, and 232B. The drivers 232R, 232G, and 232B directly modulate the laser light sources 230R, 230G, and 230B based on the input modulation control signal. Specifically, each driver circuit passes currents having the same amplitude and the same phase to the corresponding laser light sources based on the modulation control signal. As a result, the laser light sources 230R, 230G, and 230B are described as pulse lights having the same intensity corresponding to the wavelengths of R, G, and B (hereinafter referred to as “R pulse light”, “G pulse light”, and “B pulse light”). Oscillates at the same time. The light emission timing of each color pulse is not limited to the same time, but may be sequential (for example, in the order of R, G, and B). In addition, the emission light amount of each color pulse light may be set or adjusted in consideration of the transmittance of the fibers constituting the scanning medical probe 100, the sensitivity of the photodetector, the intensity of scattered light from the subject, and the like. .

  The R pulse light, G pulse light, and B pulse light oscillated from each laser light source enter the optical coupler 234. The optical coupler 234 combines and emits each incident pulsed light in a state where the phases are aligned. Hereinafter, for convenience of explanation, the pulsed light coupled by the optical coupler 234 is referred to as “coupled pulsed light”.

  When the light source is a single fiber laser, timing control for synchronizing the pulsed light of each wavelength is not necessary. Therefore, there is an advantage that the circuit configuration around the laser light source can be simplified. Further, since the pulsed light that has already been coupled is oscillated, there is an advantage that the optical coupler 234 is unnecessary.

  The combined pulse light emitted from the optical coupler 234 enters the incident end 112a of the single mode fiber 112 included in the scanning medical probe 100. The single mode fiber 112 is accommodated in the outer skin member (sheath 132 shown in FIG. 3 described later) of the scanning medical probe 100 from the optical connector portion 110 to the insertion portion distal end 130a. The combined pulse light incident on the incident end 112a is propagated by repeating total reflection inside the single mode fiber 112. The propagated coupled pulse light is emitted from the exit end 112b of the single mode fiber 112 disposed inside the insertion portion distal end 130a. The transmission path of the pulsed light is not limited to a single mode fiber but may be a multimode fiber.

  FIG. 3 is a front view schematically showing the configuration of the insertion portion distal end 130a of the first embodiment. FIG. 4A is a side view schematically showing an internal configuration of the insertion portion distal end 130a when the insertion portion distal end 130a is viewed from the direction of arrow A in FIG. FIG. 4B is a top view schematically showing an internal configuration of the insertion portion distal end 130a when the insertion portion distal end 130a faces the arrow B direction in FIG. In the following, in describing the configuration of the scanning medical probe 100, for convenience, the longitudinal direction of the scanning medical probe 100 is the Z direction, the two directions orthogonal to the Z direction and orthogonal to each other are the X direction, and Y Defined as direction. Further, the reference axis “AX” is attached to the central axis of the scanning medical probe 100.

  The sheath 132 shown in FIG. 3 or 4 is a protective tube of the scanning medical probe 100 having flexibility. The sheath 132 has a shape extending from the insertion portion distal end 130a to the optical connector portion 110, and protects various built-in components of the scanning medical probe 100. The outer diameter dimension of the sheath 132 is much smaller than the outer diameter of a conventional electronic scope because the scanning medical probe 100 is not mounted with a solid-state imaging device or the like. Therefore, the scanning medical probe 100 achieves even lower invasiveness than a conventional electronic scope.

  The scanning medical probe 100 has a forceps raising base 160. The forceps raising base 160 raises the treatment tool inserted and passed through a forceps channel (not shown) inside the sheath 132 toward the affected area or the like.

As shown in FIG. 4A or 4B, a support 134 is provided inside the sheath 132. The support 134 supports the piezoelectric actuator 136. A single mode fiber 112 is passed through the piezoelectric actuator 136. The single mode fiber 112 has a tip 112c protruding from the tip of the piezoelectric actuator 136 by a predetermined amount, and is supported by the piezoelectric actuator 136 in a cantilever state. In the vicinity of the rear end of the piezoelectric actuator 136, electrodes 136X ₁ , 136X ₂ , 136Y ₁ , 136Y ₂ are provided. Each electrode has, for example, the same size and the same shape. Electrode 136X ₁ and the electrode 136X ₂ are arranged symmetrically about the Y direction of a straight line passing through the central axis of the single mode fiber 112. Electrode 136Y ₁ and the electrode 136Y ₂ are arranged symmetrically about the X direction of the straight line passing through the central axis of the single mode fiber 112. Each electrode has a terminal connected to an electric wire (not shown) housed in the electrical connector portion 120. Electrodes 136X ₁ and 136X _2, when allowed to connect the electrical connector 120 and the electrical connector portion 220 is connected to the X-axis driver 236X included in the processor 200. Electrodes 136Y ₁ and 136Y _2, when allowed to connect the electrical connector 120 and the electrical connector portion 220 is connected to the Y-axis driver 236Y included in the processor 200.

The system controller 240 outputs predetermined drive control signals to the driver circuits of the X-axis driver 236X and the Y-axis driver 236Y. The X-axis driver 236X applies an AC voltage Vx between the electrodes 136X ₁ and 136X ₂ based on the drive control signal to resonate the piezoelectric actuator 136 in the X direction. Based on the drive control signal, the Y-axis driver 236Y applies an AC voltage Vy having the same frequency as the AC voltage Vx and orthogonal in phase between the electrodes 136Y ₁ and 136Y ₂ to resonate the piezoelectric actuator 136 in the Y direction. . The AC voltages Vx and Vy are respectively defined as voltages that linearly increase in amplitude and reach effective values (Vx) and (Vy) over time (Vx) and (Vy).

FIG. 5 is a diagram showing the emission position Pi (i = 0 to n) of each coupled pulsed light when the piezoelectric actuator 136 is driven. In FIG. 5, for convenience of explanation, the origin is set slightly above the initial position P ₀ (position when the piezoelectric actuator 136 is not driven) of the exit end 112 b of the single mode fiber 112. The injection end 112b has an initial position P on a surface that approximates the XY plane (hereinafter referred to as “XY approximate surface”) by combining the kinetic energy in the X and Y directions by the piezoelectric actuator 136. Rotate to draw a spiral pattern SP around _zero . The rotation trajectory of the injection end 112b increases in proportion to the applied voltage, and draws a trajectory of a circle having the largest diameter when the AC voltage having the effective values (Vx) and (Vy) is applied. The coupled pulsed light incident on the incident end 112a of the single mode fiber 112 is a period (ie, a period corresponding to time (Vx) or (Vy)) from immediately after application of AC voltage to the piezoelectric actuator 136 is stopped. Hereinafter, it is referred to as a “sampling period”.), And the injection is continued from the injection end 112b. Each combined pulse light is sequentially emitted from the emission end 112b at the timing of the emission positions P ₀ , P ₁ , P ₂ ,..., P _n−2 , P _n−1 , and P _n during the sampling period. .

The vibration of the distal end portion 112c of the single mode fiber 112 is gradually attenuated after the sampling period has elapsed, since the application of the AC voltage to the piezoelectric actuator 136 is stopped. With the such attenuation, circular motion of the exit end 112b of the single mode fiber 112 on the XY approximate surface is gradually attenuated, and stops at the initial position P ₀ after a predetermined time. For convenience of explanation, the duration of the sampling period has ended and the exit end 112b is stopped at the initial position P ₀ referred to as "braking period". A period corresponding to one frame (or one field) includes a sampling period and a braking period. In order to shorten the braking period, a reverse phase voltage may be applied to the piezoelectric actuator 136 in the initial stage of the braking period so as to positively apply the braking torque.

  As shown in FIG. 4A, in front of the single mode fiber 112, the direct-view objective optical system 138 and the side-view objective optical system 140 are separately provided in each of the two spaces separated by the wall 150. An independent objective optical system is arranged. The direct-view objective optical system 138 is arranged so that the optical axis is parallel to the long axis direction (center axis AX direction) of the scanning medical probe 100. The side-view objective optical system 140 has an optical configuration in which the optical axis of the lens closest to the object (observation target) side is orthogonal to the optical axis of the direct-view objective optical system 138.

  The combined pulse light emitted from the exit end 112b of the single mode fiber 112 is incident on either the direct-view objective optical system 138 or the side-view objective optical system 140 according to the deflection angle of the tip 112c of the single mode fiber 112. To do.

  On the surface of the wall portion 150 facing the emission end 112b of the single mode fiber 112, a laser light absorbent 152 having a high light absorption rate for the laser light having the wavelength used is applied. Due to the light absorption action of the laser light absorber 152, an unwanted scattering component is incident on the objective optical system which is not intended originally (for example, the combined pulsed light emitted toward the direct-view objective optical system 138 is scattered by the wall portion 150). Etc.) is effectively suppressed. Further, it is possible to prevent the regular reflection component on the surface from entering the exit end 112b.

  The combined pulsed light incident on the direct-view objective optical system 138 forms a spot Si on the observation target positioned in front of the insertion portion distal end 130a by the power of the direct-view objective optical system 138. The combined pulsed light incident on the side-view objective optical system 140 forms a spot Si on the observation target positioned on the side of the insertion portion tip 130a by the power of the side-view objective optical system 140 while being bent by the mirror M. .

  FIGS. 6A and 6B are diagrams for explaining the spot Si formed on the observation target. In FIG. 6A or 6B, the same subscript as the injection position Pi is attached to the spot Si corresponding to the injection position Pi in FIG. FIGS. 6A and 6B show the spots Si formed on the observation target via the side-view objective optical system 140 and the direct-view objective optical system 138, respectively, during one sampling period. As is clear from FIGS. 5 and 6, the combined pulse light emitted when the Y coordinate in FIG. 5 is positive passes the spot Si onto the observation target via the side-view objective optical system 140. Form. In addition, the combined pulse light emitted when the Y coordinate in FIG. 5 is negative forms a spot Si on the observation target via the direct-view objective optical system 138. In addition, the spiral solid line in FIG. 6A or FIG. 6B is a virtual scanning locus drawn on the assumption that continuous light is scanned on the observation target instead of pulsed light.

  The relationship between the emission position Pi of each combined pulse light during the sampling period and the formation position of the spot Si in the observation field corresponding to the emission position Pi is obtained in advance as a result of repeated experiments. Further, the relationship between the formation position of each spot Si and the pixel position at the time of imaging by detecting the reflected pulse light from the formation position is also calculated in advance. Based on this known information, the system controller 240 controls the X-axis driver 236X and the Y-axis driver 236Y (that is, controls the AC voltage applied to each piezoelectric actuator) and controls the drivers 232R, 232G, and 232B ( In other words, each modulation control of each laser light source during the sampling period is repeated at a cycle according to the frame rate.

  As shown in FIG. 4, the scanning medical probe 100 includes a direct-view light-receiving fiber bundle 142A and a side-view light-receiving fiber bundle 142B. The direct-viewing light receiving fiber bundle 142A is supported by the sheath 132 so that the incident end is positioned in front of the insertion portion distal end 130a. The side-viewing optical fiber bundle 142B is supported by the sheath 132 so that the incident end is positioned on the side wall surface of the sheath 132. Although not shown in FIG. 4, the respective light receiving fiber bundles are bundled behind the support 134, and constitute an optical fiber bundle 142.

  The spot Si formed on the observation target via the direct-view objective optical system 138 is scattered on the observation target and is incident on the direct-view light receiving fiber bundle 142A. The spot Si formed on the observation object via the side-view objective optical system 140 is scattered on the observation object and enters the side-view light-receiving fiber bundle 142B. The direct-viewing light-receiving fiber bundle 142A and the side-viewing light-receiving fiber bundle 142B are disposed relatively apart from each other with their incident end faces orthogonal to each other. Therefore, the component scattered on the observation object located in front of the insertion portion distal end 130a does not substantially enter the side-viewing light-receiving fiber bundle 142B. In addition, the component scattered on the observation object located on the side of the insertion portion distal end 130a does not substantially enter the direct-view light receiving fiber bundle 142A.

  The reflected pulsed light incident on each light receiving fiber bundle is propagated inside the optical fiber bundle 142 toward the end. The end of the optical fiber bundle 142 is accommodated in the optical connector unit 110 and is coupled to the optical separator 238 of the processor 200 through a connecting portion between the optical connector unit 110 and the optical connector unit 210.

  The optical fiber bundle 142 is merely a bundle of about several tens (for example, 80) optical fibers. Therefore, the optical fiber bundle 142 has a much smaller diameter than a conventional electronic scope or an optical fiber bundle of a fiberscope (for example, an optical fiber bundle in which several hundred to thousands of optical fibers are bundled).

  The optical separator 238 converts reflected pulsed light from the optical fiber bundle 142 into reflected pulsed light of each wavelength of R, G, and B (hereinafter, “reflected R pulsed light”, “reflected G pulsed light”, “reflected B pulsed light”). Are output to the photodetectors 250R, 250G, and 250B.

  As described above, the combined pulse light is guided by the single single mode fiber 112 and irradiates the observation target. Therefore, the amount of reflected pulsed light reflected on the observation target is very small. In order to detect such weak light reliably and with low noise, high-sensitivity photodetectors such as photomultiplier tubes are employed for the photodetectors of the photodetectors 250R, 250G, and 250B.

  The photodetectors 250R, 250G, and 250B photoelectrically convert the received reflected pulse light of each wavelength to generate an analog signal and output the analog signal to a subsequent circuit. An analog signal corresponding to the reflected pulse light of each wavelength detected by each photodetector is sampled and held, and converted into a digital signal sequence by A / D converters 252R, 252G, and 252B. The converted digital signal sequence is input to a DSP (Digital Signal Processor) 254.

  FIG. 7 is a block diagram showing the configuration of the DSP 254 of the first embodiment. As shown in FIG. 7, the DSP 254 includes a waveform storage circuit 254a having regions 254aR, 254aG, and 254aB that are physically or logically separated for digital signal sequences corresponding to the R, G, and B wavelengths. Have. The waveform storage circuit 254a latches each digital signal sequence from the A / D converters 252R, 252G, and 252B in each corresponding region. The digital signal sequence latched in each corresponding area is sequentially discarded after a predetermined time has elapsed in consideration of the capacity of the waveform storage circuit 254a.

  The waveform storage circuit 254a is created based on the above-described known information, the position in the observation visual field where the spot Si of each combined pulsed light is formed (according to another aspect, the address of the pixel constituting the image), A table that associates the timing T at which the reflected pulse light from each spot Si is detected is held. The waveform accumulation circuit 254a monitors the digital signal sequence latched in each corresponding region while referring to the above table, and converts the signal corresponding to each wavelength at each timing T into image information (that is, the signal in the region 254aR is R color). , A signal of the region 254aG is detected as a G-color luminance value, and a signal of the region 254aB is detected as a B-color luminance value), and a pixel address corresponding to the timing T is assigned to the detected signal. In the present specification, processing (pixel address allocation processing) for determining the pixel arrangement of the image information represented by the signal based on the signal detection timing T is referred to as “pixel mapping processing”. By such pixel mapping processing, spatially discrete pixels are arranged in an appropriate order to obtain a direct view image or a side view image.

  As described above, the combined pulse light corresponding to the negative Y coordinate in FIG. 5 forms the spot Si constituting the direct-view image on the observation target. On the other hand, the combined pulsed light having a positive Y coordinate in FIG. 5 forms a spot Si constituting the side view image on the observation target. Therefore, the waveform accumulating circuit 254a performs pixel mapping processing of the direct-view image using the signal at the timing T (the AC voltage Vy is a negative amplitude period) corresponding to the former, and the direct-view image information is stored in the direct-view image memory Write sequentially to 254b. Further, pixel mapping processing of the side-view image is performed using a signal corresponding to the latter at a timing T (AC voltage Vy is a timing with a positive amplitude period), and side-view image information is sequentially stored in the side-view image memory 254c. Write.

  The direct-view image memory 254b and the side-view image memory 254c are frame buffers, and buffer a predetermined amount of information (for example, image information for one frame (or one field)). The image information reading circuit 254d conforms the image information buffered in the direct-view image memory 254b or the side-view image memory 254c to a predetermined standard (for example, NTSC (National Television System Committee), etc.) according to the timing control by the system controller 240. The data are read out in the matching order and output to the mask generation circuit 254e. The mask generation circuit 254e generates and adds predetermined masking data to a pixel address that does not have direct-view or side-view image information, and outputs the masking data to the video signal output circuit 256.

The video signal output circuit 256 converts the input image information into a video signal conforming to a predetermined standard and outputs the video signal to the monitor 300. As a result, a color image to be observed consisting of R color, G color, and B color is displayed on the monitor 300. Here, FIG. 8A and FIG. 8B show a direct-view image 400 and a side-view image 500 displayed on the monitor 300. The case that the image using all of the image information corresponding to the spot S ₀ to S _n, the monitor 300, as the observation region is semicircular view image 400 and the lateral vision shown in FIG. 8 (a) An image 500 is displayed. When an image is constructed using only pixel information corresponding to the spots Si in the regions R ₁ and R ₂ indicated by the broken lines in FIGS. 6A and 6B, the image is shown in FIG. As shown, a direct-view image 400 and a side-view image 500 having a rectangular observation area are displayed. In general, this type of observation image often has a region of interest in the center rather than the periphery. Therefore, even when trimming corresponding to the region R ₁ or R ₂ is performed and image information of the peripheral portion is not displayed, diagnosis, treatment, etc. are not substantially affected. The size, shape, display position, and the like of the observation area can be appropriately changed by assigning pixel addresses in the pixel mapping process. In addition, image distortion caused by optical factors can be corrected as appropriate by assigning pixel addresses in the pixel mapping process.

  The scanning trajectory of the combined pulsed light on the observation target can be appropriately changed. Specifically, the scanning locus is substantially circular in the first embodiment, but may be elliptical. In order to make the scanning locus elliptical, the balance of the amplitudes of the AC voltage Vx and the AC voltage Vy may be changed with respect to the first embodiment. For example, when scanning an ellipse according to the aspect ratio of the image, the difference in scanning speed generated between the inner and outer peripheral sides of the scanning trajectory can be reduced compared to the case of scanning in a circular shape. it can. For example, since the observation target can be scanned at a relatively uniform speed, spots Si can be formed on the observation target at uniform intervals (uniform pixel arrangement according to another expression).

  FIG. 9 is a side view similar to FIG. 4A schematically showing the internal configuration of the insertion portion distal end 130az of the scanning medical probe 100 of the second embodiment of the present invention. The scanning medical probe 100 of the second embodiment is different from the scanning medical probe 100 of the first embodiment only in the configuration around the objective optical system. In each embodiment after the second embodiment, the same or similar components as those of the first embodiment are denoted by the same or similar reference numerals, and description thereof is omitted.

  As shown in FIG. 9, the insertion portion distal end 130az has a direct-view objective optical system 138z and a side-view objective optical system 140z. In the second embodiment, the mirror Mz of the side-view objective optical system 140z has the function of the wall 150 of the first embodiment. Therefore, in 2nd embodiment, the structure of insertion part front-end | tip 130az is simplified and the further diameter reduction of insertion part front-end | tip 130az is achieved. Note that a laser light absorbent 152z having a high light absorptance with respect to a laser beam having a working wavelength is applied to the side end surface of the mirror Mz facing the emission end 112b of the single mode fiber 112.

  FIG. 10 is a diagram for explaining the positional relationship between the electrodes of the piezoelectric actuator 136y included in the scanning medical probe 100 according to the third embodiment of the present invention. FIGS. 11A to 11C are diagrams for explaining the relationship between the rotation locus of the exit end 112b of the single mode fiber 112 on the XY approximate plane and the pixel arrangement in the third embodiment.

As shown in FIG. 10, the electrode 136X ₁ and the electrode 136X _2, like the first embodiment, they are arranged symmetrically about the Y 'axis in FIG. 10. On the other hand, unlike the first embodiment, the electrode 136Y ₁ and the electrode 136Y ₂ are arranged at asymmetric positions with the X ′ axis in FIG. When AC voltages Vx and Vy are applied, the piezoelectric actuator 136y resonates so as to draw an elliptical trajectory while the center of rotation is eccentrically moved in the Y direction by the generation of a polarization vector corresponding to the asymmetry of the electrode arrangement. To do. By such resonance operation, the exit end 112b of the single mode fiber 112 is gradually rotated in the direction of arrow C during the sampling period to draw an ellipse, and gradually in the direction of arrow D (direction corresponding to the Y direction) in FIG. shift. In the third embodiment, in order to draw an elliptical locus, the frequencies of the AC voltages Vx and Vy are set to different values (because the resonance frequencies are different between the X direction and the Y direction).

  FIG. 11B shows a virtual scanning trajectory (solid line) drawn on the assumption that continuous light is scanned on the observation target via the direct-view objective optical system 138, and a direct-view rectangular observation region. The relationship with 500 is shown. FIG. 11C shows a virtual scanning locus (solid line) drawn on the assumption that continuous light is scanned on the observation target via the side-view objective optical system 140, and a side-view rectangle. The relationship with the observation area 400 is shown. As shown in FIGS. 11B and 11C, the combined pulsed light sequentially scans the observation targets on the direct viewing side and the side viewing side for each horizontal scanning line. Therefore, image information for each horizontal scanning line is sequentially input to the DSP 254. Therefore, the image information readout circuit 254d does not need to rearrange the image information of each pixel address into an order compliant with a predetermined standard such as NTSC as in the other embodiments, and the input order remains as it is in the subsequent circuit. Can be output. For this reason, the processing load and processing speed of the DSP 254 are improved. Further, the amount of image information to be stored in the direct view image memory 254b or the side view image memory 254c can be reduced, and the memory utilization efficiency is improved.

  FIG. 12A is a side view similar to FIG. 4A schematically showing the internal configuration of the insertion portion distal end 130ax of the scanning medical probe 100 of the fourth embodiment of the present invention. FIG. 12B is a side view schematically showing the configuration of the forceps raising base built in the insertion portion distal end 130ax of the scanning medical probe 100 according to the fourth embodiment of the present invention and its periphery.

  As shown in FIG. 12A, a support body 134x formed integrally with the support shaft 135 is provided as an alternative to the support body 134 at the insertion portion distal end 130ax. Further, as shown in FIG. 12B, a forceps raising wire 161 is stretched inside the sheath 132. The forceps raising wire 161 is pulled to the proximal end side of the scanning medical probe 100 in accordance with the operation of the operation unit (not shown) at the hand of the scanning medical probe 100. At this time, the forceps raising lever 162 joined to the tip of the forceps raising wire 161 is pulled in the direction of arrow E in FIG. 12B, and the forceps raising stand 160 formed integrally with the forceps raising lever 162. Rises in the direction of arrow F in FIG.

  A pulley 163 that rotates together with the forceps raising base 160 is attached to a fulcrum of the forceps raising base 160 or the forceps raising lever 162. An interlocking wire 164 is hung on the pulley 163. The interlocking wire 164 is also hung on the support shaft 135 at a predetermined distance from the pulley 163. The support shaft 135 (and the support body 134x integrally formed with the support shaft 135) is rotated by the rotation of the pulley 163 accompanying the raising of the forceps raising base 160, and the distal end portion 112c of the single mode fiber 112 is moved as shown in FIG. a) Move in the direction of the middle arrow G. That is, when the forceps raising base 160 is raised, the rotation center (rotation reference position) of the distal end portion 112 c of the single mode fiber 112 is shifted to the side-view objective optical system 140. As a result, the exit end 112b of the single mode fiber 112 is rotated mainly within the pupil of the side-view objective optical system 140, and the side-view side scanning range is expanded. For example, the operator can finely observe the periphery of the treatment tool raised on the forceps raising stand 160 with an enlarged image.

  As described above, according to each embodiment of the present invention, a scanning medical probe that is capable of capturing images of viewpoints of both a direct-view observation image and a side-view observation image while having a small diameter, and the scanning medical A medical observation system having a probe is provided.

  The above is the description of the embodiment of the present invention. The present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the technical idea of the present invention.

1 Medical Observation System 100 Scanning Medical Probe 136 Piezoelectric Actuator 138 Direct Viewing Objective Optical System 140 Side Viewing Objective Optical System 200 Processor 240 System Controller 254 DSP
300 monitors

Claims (9)

In a scanning medical probe that scans light irradiated from a light source on an object,
A first optical fiber that transmits light emitted from the light source toward the object;
Vibration means for vibrating the first optical fiber so that the exit end of the first optical fiber draws a predetermined rotation locus;
An objective optical system for condensing the light emitted from the exit end onto the object, the direct-view objective optical system facing the long axis of the scanning medical probe, and the direct-view objective optical system A side-view objective optical system oriented in a direction perpendicular to
A second optical fiber that transmits the reflected light of the light collected on the object to a predetermined external device;
Have
The vibration means vibrates the vicinity of the emission end so that light emitted from the emission end of the first optical fiber selectively enters the direct-view objective optical system or the perspective objective optical system. A scanning medical probe characterized by the above. A wall portion that divides a space in front of the injection end into two spaces;
2. The scanning medical probe according to claim 1, wherein the direct-view objective optical system and the side-view objective optical system are arranged in each of the divided spaces.   The scanning medical probe according to claim 2, wherein a material having a high light absorptance with respect to the light is applied to a surface of the wall portion facing the emission end.   The wall portion is a mirror portion included in the side-view objective optical system for bending the light incident on the side-view objective optical system and emitting it to the side of the scanning medical probe. The scanning medical probe according to claim 2, wherein the scanning medical probe is characterized.   The vibration means rotates the emission end around a predetermined rotation reference position during the light emission period in which the light is emitted from the emission end. The scanning medical probe according to one item.   The oscillation means rotates the emission end around the rotation reference position while shifting a predetermined rotation reference position during a light emission period in which the light is emitted from the emission end. The scanning medical probe according to any one of claims 1 to 4. A forceps raising base for raising the forceps;
Reference position shift means for shifting the rotation reference position of the exit end with respect to the direct-view objective optical system and the side-view objective optical system in conjunction with the raising operation of the forceps raising base,
The scanning medical probe according to any one of claims 1 to 6, further comprising:   The scanning medical probe according to claim 7, wherein the reference position shift means shifts the rotation reference position of the exit end toward the side-view objective optical system. A light source for making the light incident on the first optical fiber;
A scanning medical probe according to any one of claims 1 to 8,
Image signal detection means for receiving the light transmitted by the second optical fiber and detecting an image signal;
A pixel address of the direct view image is assigned to the image signal detected at the first timing, and a pixel address of the side view image is assigned to the image signal detected at the second timing different from the first timing. Pixel arrangement determining means for determining the pixel arrangement of the image information represented by the signal;
Image creating means for spatially arranging the image information according to the determined pixel arrangement to create an image;
A medical observation system characterized by comprising:

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