JP5795557B2 - Photoacoustic attachment and probe - Google Patents

Description

  The present invention relates to a photoacoustic attachment, and more particularly to a photoacoustic attachment used by being attached to a probe. The present invention also relates to a probe including such an attachment.

  An ultrasonic inspection method is known as a kind of image inspection method capable of non-invasively examining the state inside a living body. In the ultrasonic inspection, an ultrasonic probe capable of transmitting and receiving ultrasonic waves is used. When ultrasonic waves are transmitted from the ultrasonic probe to the subject (living body), the ultrasonic waves travel inside the living body and are reflected at the tissue interface. By receiving the reflected sound wave with the ultrasonic probe and calculating the distance based on the time until the reflected ultrasonic wave returns to the ultrasonic probe, the internal state can be imaged.

  In addition, photoacoustic imaging is known in which the inside of a living body is imaged using a photoacoustic effect. In general, in photoacoustic imaging, a living body is irradiated with pulsed laser light such as a laser pulse. Inside the living body, for example, living tissue absorbs the energy of pulsed laser light, and ultrasonic waves (photoacoustic signals) are generated by adiabatic expansion due to the energy. By detecting this photoacoustic signal with an ultrasonic probe or the like and constructing a photoacoustic image based on the detection signal, in-vivo visualization based on the photoacoustic signal is possible. A photoacoustic imaging apparatus is described in Patent Document 1, for example.

JP 2010-104816 A JP 2008-284136 A

  Here, it is known that an ultrasonic diagnostic imaging apparatus is used with an attachment attached to an ultrasonic probe (see, for example, Patent Document 2). However, in photoacoustic imaging that requires irradiation of the subject with laser light, it has not been studied to attach an attachment to an ultrasonic probe and perform laser light irradiation from the attachment.

  In view of the above, an object of the present invention is to provide a photoacoustic attachment that is used by being attached to an ultrasonic probe.

  In order to achieve the above object, the present invention is a photoacoustic attachment attached to a probe having an acoustic wave detector element, which guides light to be irradiated to a subject, and an acoustic wave detection surface of the probe. Provided is a photoacoustic attachment having a light guide member that emits light guided toward a subject from an opposing light emitting surface.

  In the photoacoustic attachment of the present invention, the light guide member has a first part that guides light to the acoustic wave detection surface side along the main body of the probe to be attached, and a light emission surface. And a second portion that emits light guided through the light exit surface toward the subject.

  The light guided by the first portion of the light guide member along the probe body is refracted toward the acoustic wave detector element side when viewed from the side surface of the probe body where the light is guided, and the second portion of the light guide member. It is preferable to have a refracting surface incident on this part.

  The second portion of the light guide member may include a resin lens having a refractive index different from that of the second portion main body on the light emitting surface side. The refractive index of the resin lens may be higher than the refractive index of the second partial body of the light guide member.

  The resin lens is preferably one that refracts incident light so that the emission angle of light emitted from the light emission surface approaches a right angle.

  The resin lens may have a refractive index gradient toward the center line of the light exit surface.

  The second portion of the light guide member reflects the light at the edge of the light emitting surface in the direction of the acoustic wave detection surface, and the light reflected by the first reflecting film on the light emitting surface side. It can be set as the structure which has the 2nd reflective film which reflects.

  The 2nd part of a light guide member is good also as including the light-diffusion acoustic member which is arrange | positioned so that an acoustic wave detection surface may be covered, and which has acoustic wave permeability | transmittance and light diffusibility. The light diffusing acoustic member may be formed by mixing an inorganic pigment with an acoustic material having acoustic wave permeability.

  The first portion of the light guide member may be inclined with respect to the main body of the probe to be attached so that the traveling direction of the light to be guided is inclined toward the acoustic wave detector element side when viewed from the side surface of the probe main body. .

  The second portion of the light guide member may include a transparent urethane gel. The second part of the light guide member may further include a support member that is light transmissive and that wraps and supports the transparent urethane rubber.

  The exterior which supports a light guide member is provided, and the surface at the side of the light guide member of the exterior may be formed in white.

  The present invention also provides an acoustic wave detector element disposed in a probe body and a photoacoustic attachment attached to the probe body, which guides light to be irradiated on a subject and detects acoustic waves. Provided is a probe including a photoacoustic attachment having a light guide member that emits light guided from a light emission surface facing a sound wave detection surface provided with a vessel element toward a subject.

  The photoacoustic attachment has a first portion that guides light toward the acoustic wave detection surface side along the probe body, and a light emitting surface, and emits light guided through the first portion. A configuration including a second portion that exits from the surface toward the subject can be employed.

  The second portion of the light guide member has a first reflection film that reflects light at the edge of the light emitting surface in the direction of the acoustic wave detection surface, and the acoustic wave detector element has a surface on the acoustic wave detection surface side. The second reflection film that reflects the light reflected by the first reflection film to the light emitting surface side may be formed.

  The photoacoustic attachment of the present invention guides light to be irradiated to the subject, and guides the light guided toward the subject from the light irradiation surface facing the ultrasonic detection surface of the attached probe. It has an optical member. By using such a photoacoustic attachment, it is possible to irradiate the subject with light from the photoacoustic attachment attached to the probe. Since the photoacoustic attachment moves together with the attached probe, the user can move the probe to a desired position of the subject and irradiate light at that position, and the operability is excellent. Further, since the photoacoustic attachment and the probe are integrated, the position setting of the illumination system is stable, and light can be irradiated at a desired incident angle designed for the subject. Furthermore, for example, it is possible to prepare a plurality of types of attachments having different distances from the light irradiation surface to the ultrasonic detection surface, and use them with different attachments. An attachment can be used to generate a photoacoustic image.

The block diagram which shows the photoacoustic image generating apparatus containing the attachment for photoacoustics of 1st Embodiment of this invention. (A) is a front view of an attachment, (b) is a side view of an attachment. Sectional drawing which shows the cross section of the center vicinity of an attachment. The flowchart which shows the operation | movement procedure of photoacoustic image generation. Sectional drawing which shows the attachment for photoacoustics of 2nd Embodiment of this invention. Sectional drawing which shows an example of the resin lens which has a refractive index gradient. Sectional drawing which shows the attachment for photoacoustics of 3rd Embodiment of this invention. The front view of the attachment of 4th Embodiment of this invention, (b) is a side view of an attachment. The graph which shows the relationship between the particle | grain size of inorganic pigment, and scattering efficiency. Sectional drawing of the attachment using transparent urethane rubber. Sectional drawing which shows the attachment in which the waveguide is inclined. Sectional drawing of the attachment including the exterior. Sectional drawing which shows the example in which an attachment is integrated inside a probe case. (A) is a side view of a photoacoustic attachment attached to an intraoperative ultrasonic probe, and (b) is a front view thereof. (A) is the side view of the attachment for photoacoustics attached to the ultrasonic probe for urology, (b) is the front view.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an overall configuration of a photoacoustic image generation apparatus including a photoacoustic attachment according to a first embodiment of the present invention. The photoacoustic image generation apparatus 10 includes an ultrasonic probe 11, an ultrasonic unit 12, a laser unit 13, and an attachment 14. The ultrasonic probe 11 is connected to the ultrasonic unit 12 via a cable 15 or the like. The attachment 14 is connected to the laser unit 13 via light guiding means such as an optical fiber 16.

  The laser unit 13 is a light source unit that emits laser light to be irradiated on the subject. The wavelength of the laser light emitted from the laser unit 13 is appropriately set according to the light absorber to be observed. The attachment 14 is a photoacoustic attachment attached to the ultrasonic probe 11. The attachment 14 includes a light guide member 41 that guides laser light to be irradiated onto the subject. Laser light emitted from the laser unit 13 enters the attachment 14 through the optical fiber 16 and the like, and is irradiated from the light guide member 41 to the subject. Note that the light applied to the subject is not limited to laser light, and the subject may be irradiated with light other than the laser light.

  The ultrasonic probe 11 has an acoustic wave detector (ultrasonic wave detector) 22 for detecting an acoustic wave (typically, an ultrasonic wave) from within the subject in a probe case 21. The ultrasonic detector 22 includes an ultrasonic detector element. For example, the ultrasonic detector 22 has a plurality of ultrasonic transducers (ultrasonic detector elements) arranged one-dimensionally along the longitudinal direction of the probe case 21. The ultrasonic detector 22 detects ultrasonic waves (photoacoustic signals) generated in the subject by irradiating the subject with light. The ultrasonic unit 12 receives a photoacoustic signal from the ultrasonic probe 11 via the cable 15 and generates a photoacoustic image based on the received photoacoustic signal.

  The light guide member 41 includes a waveguide (light guide path) 42 and a light guide plate 43. The waveguide 42 corresponds to a first portion that guides light toward the ultrasonic detection surface along the main body of the probe to which the attachment 14 is attached. The light guide plate 43 corresponds to a second portion that emits light guided through the first portion from the light exit surface toward the subject. The waveguide 42 is connected to the optical fiber 16 via, for example, a connector. The waveguide 42 guides the laser light incident from the laser unit 13 to the ultrasonic detection surface side of the ultrasonic detector 22 along the probe main body of the ultrasonic probe 11. The light guide plate 43 has a light emitting surface, and emits laser light guided through the waveguide 42 in the direction of the subject.

  FIG. 2 shows a state in which the attachment 14 is attached to the ultrasonic probe 11. FIG. 2A is a front view of the attachment 14, and FIG. 2B is a side view of the attachment 14. The ultrasonic probe 11 is, for example, a type of ultrasonic probe that is used by being held by a user's hand. The waveguide 42 portion and the light guide plate 43 portion of the light guide member 41 are integrally formed, and the light guide member 41 constitutes an attachment body. The light guide member 41 that is the attachment body is detachably attached to the ultrasonic probe 11 by, for example, a claw 44 or the like. Alternatively, after attaching the attachment, the light guide member 41 and the ultrasonic probe 11 may be inseparable.

  The waveguide 42 is connected to, for example, a light emitting end of the optical fiber 16 via a connector. Although only one optical fiber is depicted in FIG. 2A, a plurality of optical fibers may be arranged in the longitudinal direction of the ultrasonic probe 11 and laser light may be incident from the plurality of optical fibers. In FIG. 2B, the two waveguides 42 are provided so as to face each other with the ultrasonic probe 11 therebetween, but a configuration in which the waveguides 42 are provided only on one side is also possible. The waveguide 42 is formed in, for example, a taper shape when viewed from the front, and even if the laser light propagates in the longitudinal direction of the ultrasonic probe 11 while proceeding to the surface side where the ultrasonic transducers are arranged. Good.

  The light guide plate 43 has a light emission surface 51 at a position facing the ultrasonic detection surface 50 in which the ultrasonic transducers of the ultrasonic probe 11 are arranged. The light emitting surface 51 faces the ultrasonic detection surface 50 with a distance d corresponding to the thickness of the light guide plate 43 so as to spatially overlap the ultrasonic detection surface 50, for example. The light guide plate 43 receives laser light from the waveguide 42 and emits laser light from the light emitting surface 51 directly below the ultrasonic wave detection surface 50 toward the subject.

  A light guide plate 43 exists between the ultrasonic detection surface 50 and the subject, and the ultrasonic detector 22 detects a photoacoustic signal generated in the subject via the light guide plate 43. For the waveguide 42 and the light guide plate 43, for example, silicon resin, low density polyethylene, epoxy resin, acrylic, PMMA (Poly Methyl Methacrylate), PC (polycarbonate), or the like can be used. The light guide plate 43 is preferably formed of a material that transmits light in a wavelength range including the wavelength of light irradiated on the subject and has little attenuation of ultrasonic waves.

  FIG. 3 shows a cross section near the center of the attachment 14. The waveguide 42 guides the light guided along the probe body in the direction of the ultrasonic detector element when viewed from the side surface of the probe body where the light is guided (for example, the direction in which the ultrasonic transducers are one-dimensionally arranged). You may have the refractive surface 45 to refract. The refracting surface 45 is formed at an angle inclined with respect to the side surface of the probe case 21. The refracting surface 45 is composed of an interface between two members having different refractive indexes. The refractive index on the light incident side (optical fiber 16 side) of the waveguide 42 is made higher than the refractive index on the light emitting side (light guide plate 43 side), and the interface is formed on the side surface of the probe case 21 as shown in FIG. By inclining the light, the light traveling downward toward the paper surface can be bent toward the ultrasonic detector element (inside the ultrasonic detection surface 50). By providing such a refracting surface 45, the laser beam can be directed to the vicinity of the center of the ultrasonic wave detection surface 50 that is not easily irradiated with light.

  FIG. 4 shows an operation procedure for generating a photoacoustic image. Prior to the irradiation of the subject with the laser beam, the attachment 14 is attached to the ultrasonic probe 11 (step S1). For example, a plurality of attachments having different thicknesses d (FIG. 2B) of the light guide plate 43, that is, the distance between the ultrasonic detection surface 50 and the light emitting surface 51, are prepared, and the attachment 14 to be attached is observed. You may choose according to. For example, after the attachment 14 is attached, the light guide member 41 of the attachment 14 and the optical fiber 16 are connected by a connector or the like so that the laser light can enter the attachment 14.

  In a state where the ultrasonic probe 11 to which the attachment 14 is attached is in contact with a desired position of the subject, laser light is emitted from the laser unit 13, and the subject is irradiated with laser light from the attachment 14 (step S2). . The light absorber in the subject absorbs the energy of the irradiated laser light and generates a photoacoustic signal. The ultrasonic detector 22 of the ultrasonic probe 11 detects a photoacoustic signal from the subject (step S3). The ultrasonic unit 12 receives the photoacoustic signal detected via the cable 15, and generates a photoacoustic image based on the received photoacoustic signal (step S4). For example, the ultrasonic unit 12 displays the generated photoacoustic image on the display monitor.

  In the present embodiment, the attachment 14 attached to the ultrasonic probe 11 is constituted by the light guide member 41, and the subject can be irradiated with laser light from the attachment 14 integrated with the waveguide. In the present embodiment, when the ultrasonic probe 11 is moved, the attachment 14 attached to the ultrasonic probe 11 is also moved together. Therefore, the user moves the ultrasonic probe 11 to a desired position on the subject and moves the laser beam to that position. The operability is excellent. In the present embodiment, since the ultrasonic probe 11 and the attachment 14 are integrated, the position setting of the illumination system is stable. Therefore, the laser beam can be irradiated from the attachment 14 at the designed incident angle with respect to the subject.

  In the present embodiment, a refractive surface 45 is provided in the waveguide 42. In this case, the refracting surface 45 provides the refracting surface 45 by refracting the laser light incident from the optical fiber 16 side in the cross section shown in FIG. 3 in the direction of the ultrasonic detector element when viewed from the side of the probe body. The amount of light near the center can be increased as compared to the case where there is not. For this reason, the laser beam irradiated to the subject from near the center in the thickness direction of the ultrasonic probe 11 (for example, a direction substantially orthogonal to the longitudinal direction in which a plurality of ultrasonic detector elements are arranged one-dimensionally) that tends to be dark. Can be ensured, and the laser beam can be irradiated with a sufficient amount of light just below the ultrasonic detection surface 50.

  Next, a second embodiment of the present invention will be described. FIG. 5 shows a photoacoustic attachment according to the second embodiment of the present invention. The photoacoustic attachment 14a of this embodiment is different from the photoacoustic attachment 14 of the first embodiment shown in FIG. 3 in that the light guide plate 43a includes a resin lens 46 having a refractive index different from that of the light guide plate main body. Other points may be the same as in the first embodiment.

  The resin lens 46 is disposed on the light emitting surface 51 side of the light guide plate 43a. For example, in the cross section shown in FIG. 5, the resin lens 46 is centered in a direction orthogonal to the longitudinal direction of the ultrasonic detection surface 50 (in a direction substantially orthogonal to the direction in which a plurality of ultrasonic detector elements are arranged one-dimensionally. Are arranged symmetrically with respect to the center). The refractive index of the resin lens 46 is higher than the refractive index of the light guide plate 43a main body. The resin lens 46 refracts incident light so that the emission angle of light emitted from the light emission surface 51 of the light guide plate 43a approaches a right angle.

  Laser light emitted from the laser unit 13 (FIG. 1) enters the waveguide 42 through the optical fiber 16. The light guided through the waveguide 42 travels toward the light guide plate 43 a and further travels toward the light exit surface 51. When the laser light traveling toward the light emitting surface 51 is incident on the resin lens 46, the laser light is refracted by the refractive index difference between the resin lens 46 and the light guide plate body, and the light is emitted at an angle closer to a right angle. The light exits from the surface 51 toward the subject.

Here, the resin lens 46 may have a refractive index gradient toward the center line of the light emitting surface 51. FIG. 6 shows an example of a resin lens having a refractive index gradient. The resin lens 46 is formed of five layers of resin lens layers 46-1, 46-2, 46-3, 46-4, and 46-5 from the interface side with the light guide plate 43a. When the refractive index of the resin lens layer 46-1～46-5 and _n 1 ~n _5, the refractive index of each layer _satisfies the _{n 5> n 4> n 3} > n 2> n 1 relationship.

  In the present embodiment, the resin lens 46 is provided on the light emitting surface 51 side of the light guide plate 43a. The resin lens 46 can irradiate laser light at an angle closer to a right angle with respect to the subject by refracting incident light. Other effects are the same as those of the first embodiment.

  Next, a third embodiment of the present invention will be described. FIG. 7 shows a photoacoustic attachment according to a third embodiment of the present invention. The photoacoustic attachment 14b of this embodiment is different from the photoacoustic attachment 14 of the first embodiment shown in FIG. 3 in that it includes light reflecting films 47 and 48 that reflect the light incident on the light guide plate 43b. Other points may be the same as in the first embodiment.

  The ultrasonic detection surface 50 of the ultrasonic probe 11 and the light emitting surface 51 of the attachment 14b face each other with an interval corresponding to the thickness of the light guide plate 43b. The first reflective film 47 is formed on the light emitting surface 51 side of the light guide plate 43b. The first reflective film 47 is formed to be inclined at a predetermined angle with respect to the light emitting surface 51 directly below the light traveling direction of the waveguide 42, and in the direction of the light emitting surface 51 around the edge of the light emitting surface 51. The light that has traveled in the direction is reflected in the direction of the ultrasonic detection surface 50.

  The second reflective film 48 is formed on the ultrasonic detection surface 50 side of the light guide plate 43b. The second reflective film 48 is formed so as to cover a plurality of one-dimensionally arranged ultrasonic detector elements, for example, in parallel with the ultrasonic detection surface 50. The second reflection film 48 reflects the light reflected by the first reflection film 47 and traveling toward the ultrasonic detection surface 50 toward the light emission surface 51. The second reflective film 48 is not necessarily provided on the light guide plate 43b. For example, the second reflective film 48 can be formed on the ultrasonic probe 11. For example, the surface on the ultrasonic detection surface 50 side of a plurality of ultrasonic detector elements arranged one-dimensionally may be coated with a metal thin film, and this may be used as the second reflective film 48.

  Laser light emitted from the laser unit 13 (FIG. 1) enters the waveguide 42 through the optical fiber 16. The light guided through the waveguide 42 travels toward the light guide plate 43 b and further travels toward the light exit surface 51. The laser light traveling straight from the waveguide 42 toward the light exit surface 51 is reflected by the first reflection film 47 and travels toward the ultrasonic detection surface 50, and is reflected again by the second reflection film 48. Heading toward the light exit surface 51. The laser beam reflected by the second reflective film 48 is emitted from the opening of the first reflective film 47 toward the subject.

  In the present embodiment, light directed toward the edge of the light emitting surface 51 is reflected by the first reflective film 47 in the direction of the ultrasonic detection surface 50, and the reflected light is reflected again by the second reflective film 48. The subject is irradiated with laser light from the emission surface 51. By using the first reflective film 47 and the second reflective film 48, light can be collected near the center in the direction orthogonal to the longitudinal direction of the ultrasonic detection surface 50. In addition, by appropriately setting the relative angle between the first reflective film 47 and the second reflective film 48, the laser light applied to the subject is closer to a right angle from the light emitting surface 51. It can be emitted at an angle. Other effects are the same as those of the first embodiment.

  Next, a fourth embodiment of the present invention will be described. FIG. 8 shows a state in which the attachment according to the fourth embodiment of the present invention is attached to the ultrasonic probe. FIG. 8A is a front view of the attachment, and FIG. 8B is a side view of the attachment. The attachment 14c according to the present embodiment further includes a light diffusing acoustic member 60 having acoustic wave permeability and light diffusing properties, which is disposed so as to cover the ultrasonic detection surface 50, and is shown in FIGS. This is different from the attachment 14 of the first embodiment shown in FIG. In FIGS. 8A and 8B, the claw 44 is omitted.

  The light diffusing acoustic member 60 is formed, for example, by mixing an inorganic pigment with an acoustic material having acoustic wave permeability. As the acoustic material, rubber materials such as silicone rubber and polyurethane can be used. As the inorganic material, at least one oxide particle of titanium oxide, zirconium oxide, iron oxide, and cerium oxide can be used.

  Preferred optical characteristics of the light diffusing acoustic member 60 will be described. For example, when the average diffuse reflectance in the wavelength region of the light (measurement light) irradiated to the subject of the light diffusing acoustic member 60 is less than 85%, the light reflected by the measurement object passes through the light diffusing acoustic member 60. Artifacts (virtual images or false images) due to vibrations generated by passing through and entering the ultrasonic detector 22 and absorbing light by the ultrasonic detector 22 are generated. Further, when the average absorptance in the wavelength range of the measurement light of the light diffusing acoustic member 60 exceeds 10%, the light reflected by the measurement object is absorbed by the light diffusing acoustic member 60, and artifacts due to the acoustic waves generated there Will occur. Therefore, the light diffusing acoustic member 60 preferably has optical characteristics such that the average diffuse reflectance in the wavelength region of the measurement light is 85% or more and the average absorption rate is 10% or less. By providing the light diffusing acoustic member 60 with such optical characteristics, generation of artifacts can be suppressed.

  The size of the inorganic pigment particles mixed in the acoustic member such as silicone rubber may be appropriately adjusted within a range that does not cause a problem in terms of image where the generation of artifacts becomes an electric noise level. FIG. 9 shows the relationship between the particle size of the inorganic pigment and the scattering efficiency. The graph shown in FIG. 9 is a plot of scattering efficiency values calculated assuming Mie scattering for 756 nm light. Plot A is data for a sample in which titanium rubber (refractive index: 2.6) is mixed with silicone rubber (refractive index: 1.41), and plot B is zirconium oxide (refractive index: 2.1) with silicone rubber. It is the data about the sample which mixed 4). Plot C is data for a sample in which polystyrene (refractive index: 1.6) is mixed with silicone rubber.

  Referring to FIG. 9, when the inorganic pigment particle size is in the range of 0.05 to 0.35 μm, a high diffuse reflectance can be obtained even if the oxide particle concentration (particle concentration) relative to the acoustic material is low. You can see that Therefore, the size of the inorganic pigment particles mixed in the acoustic member is preferably 0.05 to 0.35 μm. Further, considering that the inorganic pigment particles do not increase the acoustic attenuation rate, the size of the inorganic pigment particles is preferably 0.08 to 0.2 μm. Here, “particle size” means the average value of the diameters of particles of the material type. The particle size can be measured by, for example, a dynamic light scattering method, a laser diffraction method, an image imaging method using a scanning electron microscope (SEM), or the like.

  The thickness of the light diffusing acoustic member 60 (the thickness of the thickest part) is preferably 0.5 to 2 mm. When the thickness is less than 0.5 mm, it is difficult to obtain diffuse reflectance in the wavelength range of the measurement light with a predetermined concentration. Moreover, when the thickness is thicker than 2 mm, the absorption in the wavelength region of the measurement light by the material of the member increases.

  The addition amount of the inorganic pigment is appropriately adjusted within a range in which the generation of artifacts becomes an electric noise level and does not cause a problem on an image. The amount of the inorganic pigment added is preferably 2 to 65 wt%. When the addition amount of the inorganic pigment is lower than 2 wt%, the average diffuse reflectance in the wavelength region of the measurement light does not reach 85%, and when the addition amount is more than 65 wt%, the average in the wavelength region of the measurement light The effect of increasing the diffuse reflectance is saturated.

  Generally, when the particle concentration increases to such an extent that the particles are close to a distance of half or less of the particle diameter, the scattering ability (diffuse reflectance) is saturated. For example, assuming that 0.2 μm particles enter a cubic space with a side of 0.3 μm, the scattering power is saturated when the volume fraction of the inorganic pigment is, for example, 0.155 in a mixture of silicone rubber and inorganic pigment. . Therefore, the addition amount of the inorganic pigment is appropriately set in a range where the volume fraction of the inorganic pigment in the material constituting the light diffusing acoustic member 60 is lower than 0.155. The same applies to iron oxide and cerium oxide not shown in the graph of FIG.

  In the present embodiment, the attachment 14 c includes a light diffusion acoustic member 60 that covers the ultrasonic detection surface 50 of the ultrasonic detector 22. The light diffusing acoustic member 60 can suppress the light incident on the ultrasonic detector 22, thereby suppressing artifacts caused by the light entering the ultrasonic detector 22. Other effects are the same as those of the first embodiment.

  In each of the above embodiments, an example in which the second portion of the light guide member that emits the guided light from the light exit surface toward the subject is configured by the light guide plate 43 has been described. The portion is not limited to the light guide plate 43. The second part only needs to have optical transparency and ultrasonic transparency, and a transparent urethane gel such as Sonagel (trade name) may be used for the second part. In this case, the second portion may have a light transmitting property and a bag (support member) that wraps and supports the transparent urethane rubber.

  FIG. 10 shows a cross section of an attachment using transparent urethane rubber. The cross section shown in FIG. 10 corresponds to the cross section of the side surface shown in FIG. The second portion 43 d of the light guide member includes a bag 61 and a transparent urethane gel 62. The transparent urethane gel 62 is formed of a gel material that transmits light and acoustic waves. The bag 61 has a characteristic of transmitting light and acoustic waves, and encloses and holds the transparent urethane gel 62. By wrapping the transparent urethane gel 62 with the bag 61, the shape of the transparent urethane gel 62 is easily maintained. In addition, the strength is improved. In FIG. 10, the light diffusing acoustic member 60 is disposed at a position that covers the ultrasonic detector 22 (FIG. 3) when the attachment 14 d is attached to the probe. Good.

  In each of the above embodiments, for example, in FIG. 3 and the like, the cross-sectional shape of the waveguide 42 is drawn as a rectangle, but the cross-sectional shape of the waveguide 42 is arbitrary. For example, the cross-sectional shape of the waveguide 42 may be a cross-sectional shape formed of a straight line, a spherical surface, or any other shape so that the light intensity distribution of the laser light emitted from the light emitting surface of the light guide plate 43 is as uniform as possible. Good. The waveguide 42 does not have to be parallel to the side surface of the probe body, and the waveguide 42 may be inclined with respect to the side surface of the probe body. FIG. 11 shows an attachment in which the waveguide is tilted. In the attachment 14e, the waveguide 42 (first portion of the light guide member) is attached so that the traveling direction of the light to be guided is inclined toward the detector element side of the ultrasonic detector 22 when viewed from the side of the probe body. Tilted with respect to the body of the probe. By using such an attachment 14d, light can be collected in the vicinity of the center in the direction orthogonal to the longitudinal direction of the ultrasonic detection surface 50.

  Here, in FIGS. 2A and 2B, FIG. 3, and the like, the exterior covering the light guide member 41 (FIG. 1) including the waveguide 42 and the light guide plate 43 is not shown in order to simplify the description. However, the attachment is at least partially covered with an exterior made of, for example, resin. In that case, it is preferable that at least the light guide member 41 side surface of the exterior is formed in white.

  FIG. 12 shows a cross section of the attachment including the exterior. The exterior 63 is made of, for example, ABS resin (Acrylonitrile Butadiene Styrene) resin, and a coating containing an inorganic pigment is applied to the surface of the waveguide 42 and the light guide plate 43 (inner side). As the inorganic pigment, at least one oxide particle of titanium oxide, zirconium oxide, iron oxide, and cerium oxide can be used. By the coating film of these inorganic pigments, the color inside the exterior 63 becomes white. The white here does not need to be completely white, but may be white mixed with some color such as yellow or brown. By making the inner surface of the exterior 63 white, it is possible to suppress light absorption in the exterior 63 and generation of unnecessary acoustic waves.

  Furthermore, although each said embodiment demonstrated as what attaches the attachment 14 to the outer side of the probe case 21 of the ultrasonic probe 11, it is not limited to this. FIG. 13 shows an example in which the attachment 14 is incorporated inside the probe case 21. The probe case 21 has a space for accommodating the attachment 14. The attachment 14 can be attached to the ultrasonic probe 11 by inserting the waveguide portion of the attachment 14 into the space.

  In FIGS. 2A and 2B, a hand-held type ultrasonic probe is assumed as the ultrasonic probe 11, but the ultrasonic probe to which the photoacoustic attachment is attached is not limited to the hand-held type. 14A and 14B show a state in which the photoacoustic attachment is attached to the intraoperative ultrasonic probe. FIG. 14A is a side view, and FIG. 14B is a front view. A suitable photoacoustic attachment 14 is attached to the intraoperative ultrasonic probe 11a. In this case as well, the laser light incident from the optical fiber 16 passes through the waveguide 42 and the light guide plate 43, and enters the subject from directly below the surface on which the detector elements of the ultrasonic detector 22 are arranged (ultrasonic detection surface). Irradiated.

  FIGS. 15A and 15B show a state in which the photoacoustic attachment is attached to the urinary ultrasonic probe. FIG. 15A is a side view, and FIG. 15B is a front view. A suitable photoacoustic attachment 14 is attached to the urinary ultrasonic probe 11b. In this example, similarly to the example of FIG. 13, the waveguide 42 portion is inserted into the probe body, and is held by a holding member (outer case) 49. In this case as well, the laser light incident from the optical fiber 16 passes through the waveguide 42 and the light guide plate 43, and enters the subject from directly below the surface on which the detector elements of the ultrasonic detector 22 are arranged (ultrasonic detection surface). Irradiated.

  As mentioned above, although this invention was demonstrated based on the suitable embodiment, the attachment for photoacoustics and ultrasonic probe of this invention are not limited only to the said embodiment, Various from the structure of the said embodiment. Modifications and changes are also included in the scope of the present invention.

10: Photoacoustic image generation apparatus 11: Ultrasonic probe 12: Ultrasonic unit 13: Laser unit 14: Attachment 15: Cable 16: Optical fiber 21: Probe case 22: Ultrasonic detector 41: Light guide member 42: Waveguide 43: Light guide plate 44: Claw 45: Refraction surface 46: Resin lens 47, 48: Reflective film 49: Holding member 50: Ultrasonic detection surface 51: Light emitting surface 60: Light diffusion acoustic member 61: Support member 62: Transparent urethane Gel 63: Exterior

Claims (16)

A photoacoustic attachment attached to a probe having an acoustic wave detector element,
A light guide member that guides light to be irradiated to the subject and emits the guided light toward the subject from a light exit surface facing the acoustic wave detection surface of the probe ;
The light guide member includes a first portion that guides light toward the acoustic wave detection surface along the main body of the probe to be attached, and the light exit surface, and guides light through the first portion. And a second portion that emits the emitted light from the light exit surface toward the subject . The first part refracts the light guided along the probe main body to the acoustic wave detector element side when viewed from the side of the probe main body through which the light is guided to the second part. The attachment for photoacoustics according to claim 1 , further comprising an incident refracting surface. The second part, on the light emitting surface side, the photoacoustic attachment according to claim 1 or 2 and the second part body, characterized in that the refractive index contains a different resin lens. The photoacoustic attachment according to claim 3 , wherein a refractive index of the resin lens is higher than a refractive index of the second partial body. The resin lens, the photoacoustic attachment according to claim 3 or 4 emission angle of the light emitted from the light emitting surface is characterized in that for refracting incident light so as to approach a right angle.   The photoacoustic attachment according to any one of claims 3 to 5, wherein the resin lens has a refractive index gradient toward a center line of the light emitting surface. The second portion reflects the light at the edge of the light emitting surface in the direction of the acoustic wave detection surface, and the light reflected by the first reflecting film on the light emitting surface side. photoacoustic attachment according to claim 1 or 2, characterized in that a second reflective film that reflects. Said second portion, said being arranged so as to cover the acoustic wave detection surface, according to 6 claim 1, characterized in that it comprises a light diffusing acoustic member having an acoustic wave transparency and light diffusion property Attachment for photoacoustic. 9. The photoacoustic attachment according to claim 8 , wherein the light diffusing acoustic member is formed by mixing an inorganic pigment with an acoustic material having acoustic wave permeability. The first portion is inclined with respect to a main body of a probe to be attached so that a traveling direction of light to be guided is inclined toward the acoustic wave detector element side when viewed from a side surface of the probe main body. The photoacoustic attachment according to any one of claims 1 to 9 . The photoacoustic attachment according to any one of claims 1 to 10, wherein the second portion includes a transparent urethane gel. The attachment for photoacoustics according to claim 11 , wherein the second portion further includes a support member having light transparency and enclosing and supporting the transparent urethane rubber. A photoacoustic attachment attached to a probe having an acoustic wave detector element,
A light guide member that guides light to be irradiated to the subject and emits the guided light toward the subject from a light exit surface facing the acoustic wave detection surface of the probe;
An exterior that supports the light guide member ,
The photoacoustic attachment is characterized in that the exterior is formed in white. An acoustic wave detector element disposed within the probe body;
A photoacoustic attachment attached to the probe main body, which guides light to be irradiated to a subject, from a light emitting surface facing the acoustic wave detection surface provided with the acoustic wave detector element A photoacoustic attachment having a light guide member that emits the light guided toward the subject ;
The photoacoustic attachment has a first portion that guides light toward the acoustic wave detection surface along the probe body, and the light exit surface, and is guided through the first portion. And a second portion that emits the emitted light from the light exit surface toward the subject . The second portion has a first reflective film that reflects light at an edge of the light emitting surface toward the acoustic wave detection surface;
A second reflective film for reflecting light reflected by the first reflective film to the light emitting surface side is formed on a surface on the acoustic wave detection surface side of the acoustic wave detector element. The probe according to claim 14 .   An acoustic wave detector element disposed within the probe body;
  A photoacoustic attachment attached to the probe main body, which guides light to be irradiated to a subject, from a light emitting surface facing the acoustic wave detection surface provided with the acoustic wave detector element A light guide member that emits the light guided toward the subject, and a photoacoustic attachment having an exterior that supports the light guide member,
  The probe characterized in that the exterior is formed in white.

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