JP2013220185A - Apparatus for acquiring information on subject - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for objectively confirming the condition of a subject when a worker performs an operation of holding the subject in an apparatus for performing photoacoustic photographing.SOLUTION: An apparatus for acquiring information on a subject acquires characteristic information on the subject by receiving acoustic waves passing through the subject, and includes: a pair of holding members which locate while facing each other and grip the subject; a light-irradiating means which irradiates with light the subject; a subject-detecting means which detects the position of the subject between the pair of holding members; and a condition display means which displays information regarding the position of the subject detected by the subject-detecting means. In the apparatus for acquiring information on a subject, the condition display means is mounted on a position visible by a worker when she (he) makes the pair of holding members grip the subject.

Description

  The present invention relates to a subject information acquisition apparatus.

  Up to now, many proposals have been made regarding a technique for photographing a biological image using light, and one of them is a photoacoustic photographing apparatus. The photoacoustic imaging apparatus has been shown to be particularly useful in the diagnosis of skin cancer and breast cancer, and can be used as a medical device in place of an ultrasonic diagnostic apparatus, an X-ray apparatus, an MRI apparatus, or the like conventionally used in the diagnosis. Expectations are rising.

  When measuring light such as visible light or near-infrared light is irradiated onto living tissue, the light absorbing substance inside the living body, especially the substance such as hemoglobin in the blood absorbs the energy of the measuring light and expands instantaneously. It is known that acoustic waves are generated. This phenomenon is called a photoacoustic effect, and the generated acoustic wave is also called a photoacoustic wave. In the photoacoustic imaging apparatus, information on a living tissue is visualized by measuring the photoacoustic wave. Such a tomographic technique using the photoacoustic effect is also referred to as photoacoustic tomography (PAT). By this photoacoustic imaging technique, the light energy absorption density distribution, that is, the density distribution of the light absorbing substance in the living body can be measured quantitatively and three-dimensionally to obtain a result.

  Generally, in breast cancer diagnosis in the mammary gland department, benign and malignant diagnosis is comprehensively performed based on palpation and the result of using the above-described modalities. In addition, the photoacoustic imaging apparatus has a great advantage in terms of patient burden because it allows non-exposed and non-invasive image diagnosis by using light for imaging diagnostic images. Therefore, in place of an X-ray apparatus that is difficult to repeatedly diagnose, it is expected to be used in breast cancer screening and early diagnosis.

  In a photoacoustic imaging apparatus that performs breast cancer imaging, a light source and an acoustic wave probe are scanned along a holding plate while the subject is held by a holding plate to obtain a three-dimensional photoacoustic image of the subject. At this time, in order to obtain a desired measurement result, the subject must be appropriately held. For this purpose, various information related to the device acquired by the sensor must be notified to an operator or the like.

  In the technique described in Patent Literature 1, information from a sensor is received in a system related to a catheter.

Special table 2011-504766 gazette

  In the photoacoustic imaging apparatus, light may leak from the apparatus depending on the state in which the subject is held by the holding plate. In such a case, the operator needs to adjust and correct the insertion state of the subject into the apparatus.

  However, since the holding state varies depending on the size and shape of the subject, it is difficult to appropriately adjust the insertion state unless the operator confirms the holding state. Therefore, there has been a demand for a photoacoustic imaging apparatus that can objectively confirm the insertion state of the subject when the operator adjusts the position of the subject.

  The present invention has been made in view of the above problems, and in an apparatus for performing photoacoustic imaging, a technique for objectively checking the state of a subject when an operator performs a holding operation of the subject. The purpose is to provide.

  The present invention employs the following configuration. That is, a subject information acquisition apparatus that receives acoustic waves propagating through a subject and obtains characteristic information of the subject, a pair of holding members that are positioned opposite to each other and sandwich the subject; Information relating to the light irradiation means for irradiating the subject with light, the subject detection means for detecting the position of the subject between the pair of holding members, and the position of the subject detected by the subject detection means. State display means for displaying, and the state display means is mounted at a position where an operator can visually recognize the object while holding the object between the pair of holding members in the object information acquiring apparatus. This is a subject information acquisition apparatus characterized by the above.

  The present invention also employs the following configuration. That is, a subject information acquisition apparatus that receives acoustic waves propagating through a subject and obtains characteristic information of the subject, a pair of holding members that are positioned opposite to each other and sandwich the subject; Light irradiation means for irradiating the subject with light, subject detection means for detecting whether the subject exists between the pair of holding members, and presence of the subject detected by the subject detection means Status display means for displaying information relating to the information, and the status display means is mounted at a position where the operator can visually recognize the object when the object is held between the pair of holding members in the object information acquisition apparatus. This is a subject information acquisition apparatus characterized by being configured.

  ADVANTAGE OF THE INVENTION According to this invention, in the apparatus which performs a photoacoustic imaging, when an operator performs the holding | maintenance operation | work of a subject, the technique for confirming the state of a subject objectively can be provided.

1 is a diagram illustrating a configuration of a photoacoustic imaging apparatus in Embodiment 1. FIG. FIG. 3 is a flowchart illustrating photoacoustic imaging according to the first embodiment. FIG. 6 is a diagram illustrating a configuration of a photoacoustic imaging apparatus according to a second embodiment. FIG. 6 is a flowchart illustrating photoacoustic imaging in the second embodiment.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described below should be changed as appropriate according to the configuration of the apparatus to which the invention is applied and various conditions. It is not intended to limit the following description.

  The photoacoustic imaging apparatus of the present invention utilizes the photoacoustic effect in which an acoustic wave is generated and propagated inside a subject by irradiating the subject with light (electromagnetic waves), and the characteristic information inside the subject is used as image data. It is a device to acquire. The characteristic information acquired at this time is the source distribution of acoustic waves generated by light irradiation, the initial sound pressure distribution inside the subject, or the optical energy absorption density distribution, absorption coefficient distribution, and tissue derived from the initial sound pressure distribution. The concentration distribution of the constituent substances is shown. The concentration distribution of the substance is, for example, an oxygen saturation distribution or an oxidized / reduced hemoglobin concentration distribution. Since such characteristic information is also called object information, the photoacoustic imaging apparatus of the present invention can also be called an object information acquiring apparatus.

The acoustic wave referred to in the present invention is typically an ultrasonic wave, and includes an elastic wave called a sound wave, an ultrasonic wave, or an acoustic wave. An acoustic wave generated by the photoacoustic effect is called a photoacoustic wave or an optical ultrasonic wave. The probe of the subject information acquisition apparatus receives an acoustic wave generated inside the subject.

<Example 1>
The configuration of the photoacoustic imaging apparatus and the photoacoustic imaging method in Embodiment 1 of the present invention will be described.

(Device configuration)
As shown in FIG. 1, the photoacoustic imaging apparatus of the present embodiment includes holding plates 101A and 101B that hold the subject 100, and a holding plate driving mechanism 102 that moves the holding plate and acquires the position thereof. Furthermore, the photoacoustic imaging apparatus includes an object detection sensor 103 that detects whether an object is inserted between the holding plates. The subject detection sensor corresponds to the subject detection means of the present invention. The subject detection sensor 103 may not only confirm the presence / absence of the subject, but may also acquire information such as thinness when the subject is present. Further, the photoacoustic imaging apparatus includes a light source 104 that generates measurement light and an optical device 105 that converts the generated measurement light into a desired form. The optical device corresponds to the light irradiation means of the present invention.

  Further, the photoacoustic imaging apparatus moves the positions of an acoustic wave probe (hereinafter also referred to as a probe) 106 and a probe 106 that detect photoacoustic waves that are generated by light irradiation and propagate through the subject 100. A probe driving mechanism 107 is provided. Further, the photoacoustic imaging apparatus includes a control unit 108 that controls the holding plate driving mechanism 102, the light source 104, the optical device 105, the probe 106, and the probe driving mechanism 107. Further, the control unit 108 receives the state of the subject detection sensor 103.

  Furthermore, the photoacoustic imaging apparatus includes a status display unit 109 that displays information necessary for inserting the subject into the photoacoustic imaging apparatus, such as information on the subject detection sensor. The status display unit corresponds to status display means of the present invention. Further, the photoacoustic imaging apparatus receives the photoacoustic wave acquired by the probe from the control unit 108, generates characteristic information in the subject, and further generates an information processing unit 110 that generates a photoacoustic image and the like. The display unit 111 displays a photoacoustic image or the like.

  In FIG. 1, a subject 100 to be imaged is clamped from both sides by a holding unit and fixed. The holding part is composed of a pair of holding plates 101A and holding plates 101B that are positioned to face each other. In order to change the holding distance and the pressure, the holding plate driving mechanism 102 controls the position of the holding plate. When it is not necessary to distinguish between the holding plate 101A and the holding plate 101B, they are collectively referred to as the holding plate 101. By sandwiching and fixing the subject 100 with the holding plate 101, measurement errors due to movement of the subject 100 can be reduced. Since the holding plate 101 is located on the optical path of the measurement light, the holding plate 101 preferably has a high transmittance with respect to the measurement light. Further, the holding plate 101 is preferably a member having high acoustic matching with the probe 106. For example, a member such as polymethylpentene used in an ultrasonic diagnostic apparatus or the like is used. The holding plate 101 corresponds to the holding member of the present invention.

  In order to detect whether or not the subject 100 exists between the holding plates, a subject detection sensor 103 is mounted. It is dangerous to irradiate light in a state where the subject 100 does not exist between the holding plates because light leaks from between the holding plates. In order to prevent such light leakage, the object detection sensor 103 exists. If the object detection sensor 103 does not react to the presence of the object, light cannot be irradiated under the control of the control unit. The object detection sensor 103 may be anything as long as it can detect the object, such as a sensor that detects light or a sensor that detects contact or pressure.

The light source 104 generates measurement light emitted to the subject 100. As the light source 104, an individual laser (for example, a Yttrium-Aluminium-Garnet laser or a Titanium-Sapphire laser) capable of emitting a pulse having a central wavelength in the near infrared region is generally used. The wavelength of the measurement light is selected between 530 nm and 1300 nm according to a light absorbing substance (for example, hemoglobin, glucose, cholesterol, etc.) in the subject 100 to be imaged. For example, hemoglobin in breast cancer new blood vessels to be imaged generally absorbs light of 600 nm to 1000 nm. On the other hand, since the light absorption of water constituting the living body is minimized in the vicinity of 830 nm, the light absorption is relatively increased between 750 nm and 850 nm. In addition, since the light absorption rate changes depending on the state of hemoglobin (oxygen saturation), it is possible to measure a functional change in the living body by comparing this change.

  An optical device 105 for irradiating the subject 100 with measurement light from the light source 104 in a desired shape includes an optical system such as a lens, a mirror, and an optical fiber, and a scanning mechanism that scans the holding plate 101. . Any optical system may be used as long as measurement light emitted from the light source 104 is irradiated on the subject 100 in a desired shape.

  When measurement light generated by the light source 104 is irradiated onto the subject 100 via the optical device 105, the light absorbing material 112 in the subject absorbs light and emits photoacoustic waves. In this case, the light absorbing material 112 corresponds to the sound source.

  The probe 106 detects a photoacoustic wave generated by the light absorbing material 112 and converts it into an electric signal. A photoacoustic wave generated from a living body is an ultrasonic wave of 100 KHz to 100 MHz. Therefore, the probe 106 that can receive the above-described frequency band is used as the probe 106. Any probe may be used as long as it can detect photoacoustic waves, such as a transducer using a piezoelectric phenomenon, a transducer using optical resonance, and a transducer using a change in capacitance. In addition, by using a probe in which elements are arranged one-dimensionally or two-dimensionally, photoacoustic waves can be detected at a plurality of locations at the same time, the detection time can be shortened, and the influence of vibration of the subject can be affected. Can be reduced.

  In the present embodiment, the subject 100 is irradiated with measurement light on the front surface of the probe 106. Therefore, the optical device 105 and the probe 106 are arranged at positions facing each other with the subject 100 interposed therebetween. Then, scanning control is performed in which the optical device 105 and the probe driving mechanism 107 are interlocked so as to maintain the positional relationship. However, the arrangement of the probe and the optical device is not limited to this. For example, it is conceivable to irradiate the subject with light from two holding plates at the same time, or to arrange the probe and the optical device on the same holding plate.

  The control unit 108 amplifies the photoacoustic wave electrical signal obtained from the probe 106 and converts the analog signal (analog electrical signal) to a digital signal (digital electrical signal). Then, the converted digital signal (photoacoustic signal) is transmitted to the information processing unit. Also, integration processing between digital signals for noise reduction is performed. Further, the light source 104, the optical device 105, the probe 106, and the probe driving mechanism 107 are controlled. Further, the state of the subject detection sensor 103 is received and transmitted to the state display unit 109.

  The digital signal integration process refers to repeatedly measuring the same part of the subject 100 and performing an averaging process. This is done to reduce system noise and improve the S / N ratio of the photoacoustic signal. Here, it is preferable that the necessary number of times of integration processing is set to an ideal value based on measurement performed in advance.

  The scanning control of the optical device 105 and the probe driving mechanism 107 is performed in conjunction with each other while maintaining the positional relationship between the optical device 105 and the probe 106. The optical device 105 and the probe driving mechanism 107 are two-dimensionally scanned with respect to the subject 100, and measurement is performed at each scanning position, so that even the small probe 106 acquires photoacoustic waves necessary for a wide imaging region. become able to. For example, when a breast is imaged, a full breasted photoacoustic image can be captured.

  The state display unit 109 receives and displays the state of the subject detection sensor received from the control unit. As the status display unit 109, a display device such as an LCD display can be used. As will be described in detail later, the present invention is characterized by the position where the state display unit 109 is mounted in the photoacoustic imaging apparatus. That is, it is mounted at a position that can be visually recognized by the operator.

  The information processing unit 110 generates a photoacoustic image based on the photoacoustic signal received from the control unit 108 and displays it on the display unit 111. As the information processing unit 110, a device having a high-performance arithmetic processing function or a graphics display function such as a personal computer or a workstation can be used. Here, all the contents displayed on the display unit 111 may be displayed on the status display unit 109, and the display unit 111 may not be mounted.

  In the photoacoustic imaging apparatus having the above configuration, by imaging based on the photoacoustic effect, the optical characteristic distribution of the subject 100 can be imaged and a photoacoustic image can be presented.

(Status display section)
Next, the status display unit will be described.

  In the photoacoustic imaging apparatus, an operator such as a doctor or an engineer performs a procedure when the subject is sandwiched between holding plates. For example, if the subject is a breast, the operator extends the breast so that the measurement light reaches the deep part. At this time, depending on the state of holding the object between the holding plates, a desired photoacoustic wave may not be obtained or light may leak from the apparatus. For example, if the insertion between the holding plates is insufficient, the light does not reach the deep part and an image suitable for diagnosis cannot be obtained. Therefore, the operator needs to make adjustments so as to be in a state suitable for photoacoustic imaging while confirming the insertion state. However, since the adjustment of the insertion state varies depending on the size and shape of the subject, it is necessary to objectively confirm the state of the subject detection sensor 103 and the insertion state of the subject while adjusting the position of the subject. There is.

  Here, when the information acquired by the subject detection sensor 103 is the presence / absence of the subject and the information that the subject does not exist is displayed, the operator can know that the breast is not inserted correctly. Even when the object detection sensor can detect other information related to the position of the object, such as bias of the holding state, thinness of holding, holding pressure, etc., the holding state may be adjusted using the information.

  From the above, the mounting position of the state display unit 109 needs to be mounted at a position where it can be visually recognized without greatly changing the posture when an operator such as a doctor or an engineer performs a procedure. For example, the mounting position may be determined in view of the viewing angle of the state display unit 109 and the average height of a doctor or engineer.

  The mounting position of the state display unit is preferably a position where an operator who directly performs a procedure by visually recognizing between the pair of holding plates can confirm the position without moving or changing the posture. For example, the side surface of the photoacoustic imaging apparatus (subject information acquisition apparatus) is good. However, the mounting position is not limited to this, and any surface that intersects with the extension line of the subject holding surface of the pair of holding plates in the outer surface of the main body of the photoacoustic imaging apparatus may be used. Further, if the pair of holding plates is made of a transparent member, it can be mounted on any of the outer surfaces of the photoacoustic imaging apparatus.

(Processing flow)
Next, the flow from when the photoacoustic imaging apparatus of the present invention performs photoacoustic imaging according to the operator's instruction to display the photoacoustic image will be described with reference to the flowchart of FIG.

In FIG. 2A, in order to start this flow in step S200, the user (
The worker) needs to confirm the display of the state display unit 109 and determine that the holding state of the subject 100 is appropriate. A series of processing is started by instructing the start of photoacoustic imaging. There are various criteria for determining the holding state. For example, the entire breast may be stretched evenly and thinned. Whether the entire breast is thin or not can be determined by checking whether the distance between the holding plates is sufficiently close.If the information detected by the sensor is displayed on the status display section, refer to it to perform the holding operation. It can be executed smoothly.

  Further, when an acoustic wave is received by the probe, a good image cannot be acquired if air is present between the breast and the breast, and the holding plate needs to be in close contact. Moreover, when using the acoustic matching agent for taking an acoustic matching, it is also confirmed whether it is arrange | positioned appropriately.

  In consideration of these various factors, the operator performs holding by appropriately moving the holding plate driving mechanism 102 while operating the breast by a technique. At this time, it is also confirmed whether the subject detection sensor 103 is reacting. Information necessary for this confirmation is displayed on the state display unit 109 at a position where the operator can visually recognize the procedure while performing the procedure. Thereby, preparation is completed and photoacoustic imaging is started.

  In step S <b> 201, the control unit 108 receives the state of the subject detection sensor 103. When the subject detection sensor 103 is reacting (S201 = YES), the subject holding state is appropriate, and imaging is continued. If the subject detection sensor 103 has not reacted (S201 = NO), the imaging is terminated (step S204). Here, when the subject detection sensor 103 is not responding, the imaging start in S200 may be disabled.

In step S202, a photoacoustic signal is acquired. Details of this processing will be described with reference to FIG.
In step S2020, photoacoustic signal acquisition is started.
In step S2021, the optical device 105 and the probe 106 are moved to the imaging initial position under the control of the control unit 108.

In step S2022, the subject 100 is irradiated with light from the optical device 105.
In step S2023, the probe 106 acquires a photoacoustic wave generated by light irradiation. The electrical signal based on the photoacoustic wave is processed by the information processing unit 110 to become a photoacoustic signal.
In step S2024, it is determined whether the acquired photoacoustic signal has reached a preset number of integrations. If the number of integration has been reached (S2024 = YES), the process proceeds to step S2025. If it has not been reached (S2024 = NO), the process returns to step S2022 to acquire the photoacoustic signal again.

  In step S2025, it is determined whether the acquisition of photoacoustic signals for all the imaging regions is completed. If there is an unacquired area (S2025 = NO), the process proceeds to step S2026, and the optical device and the probe are moved to the next imaging position. This process is also called step-and-repeat. Steps S2022 to S2024 are repeated again. On the other hand, when the signal acquisition from the imaging region is completed (S2025 = YES), the acquisition of the photoacoustic signal is terminated (step S2027).

Returning to FIG. 2A again, the description will be continued.
In step S203, the information processing unit 110 generates characteristic information in the subject from the acquired photoacoustic signal, and converts it into a format of image data that can be displayed on the display unit. And the display part 111 displays a photoacoustic image.
A photoacoustic image is generated and displayed according to the above flow.

According to the present embodiment, the operator can hold the subject while confirming the state of the subject detection sensor 103. As a result, it is possible to perform an appropriate procedure according to the state of holding the subject, and to perform good photoacoustic imaging. In other words, although the state of insertion of the subject into the apparatus varies depending on the size and shape of the subject, failure in subject insertion adjustment can be reduced by performing the procedure while confirming (visually confirming) the detection result.

<Example 2>
In the present embodiment, a case will be described in which confirmation regarding the holding state of the subject is performed in more detail than in the first embodiment.

  In general, when applying a photoacoustic wave device to a living body, it is necessary to limit the amount of irradiation light to a predetermined threshold value or less in order to avoid damage to living tissue. This value is called MPE (maximum permissible exposure).

  In the photoacoustic imaging apparatus, due to the characteristics of the optical system of the optical apparatus 105, the light irradiation density increases as the distance from the light projecting unit to the subject decreases. Therefore, it is necessary to control (weaken) the amount of emitted light by the light source 104 or the optical device 105 so that the irradiation density on the subject does not exceed MPE throughout the movable range of the holding plate 101. However, when the movable range of the holding plate 101 is large, the amount of emitted light is greatly limited, so that a sufficiently large signal cannot be obtained by the probe 106, which may lead to a decrease in contrast of the photoacoustic image. There is.

Therefore, in this embodiment, when the distance between the holding plates is larger than a predetermined value, that is, when the distance from the optical device 105 to the holding plate 101B (hereinafter also referred to as a light projection distance) is equal to or smaller than a predetermined value. , Making light irradiation impossible.
As described above, when the projection distance from the optical device is equal to or less than a predetermined value, it is possible to suppress the amount of light irradiated to the subject to a value that does not exceed the MPE by disabling light irradiation. Further, by performing light amount control accurately, it is possible to irradiate light having a large amount of light as long as it does not exceed MPE, so that it is possible to capture an image without reducing the contrast of the photoacoustic image.

  Therefore, by displaying information on the projection distance on the status display unit 109, it is possible to prompt the operator to appropriately hold the subject by the holding plate, and to prevent leakage of light and Appropriate pressure holding of the specimen becomes possible.

  Here, in this embodiment, an example in which light irradiation is impossible when the projection distance is 80 mm or less is shown. However, this distance is set as an ideal value in consideration of the size of the breast and the configuration of the apparatus in advance, and is not limited to this value.

(Device configuration)
An embodiment of the photoacoustic imaging apparatus in Example 2 will be described with reference to FIG. However, the same modules as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. The photoacoustic imaging apparatus according to the present embodiment is characterized in that it includes a light projecting sensor 300 that is connected to the control unit 108 and detects a distance irradiated with light. The light projecting sensor corresponds to the distance detecting means of the present invention.

In this embodiment, the light projection sensor 300 is installed at a light projection distance of 80 mm from the optical device 105. The light projection sensor 300 detects the light projection distance from the optical device to the subject, and reacts if it is 80 mm or more. On the other hand, if the projection distance is less than 80 mm, the projection sensor 300 is not reacted.
It is dangerous to irradiate light in a state where the light projection sensor 300 is not reacting because the distance from the optical device to the subject is too close and may exceed the MPE. Therefore, the control unit 108 performs control so that light cannot be emitted unless the light projection sensor 300 is reacted.

The light projecting sensor 300 may be anything as long as it can detect the holding plate, such as a sensor that detects light (light detection sensor).
Note that the method for obtaining the information regarding the light projection distance is not limited to this, and any detection means that can detect the distance between the optical device 105 and the holding plate 101 may be used. For example, the distance from the optical device 105 may be obtained using an existing position sensor provided on the holding plate 101. For example, since the positional relationship between the optical device 105 and the holding plate 101 is known from the configuration of the device, if the compression distance between the two holding plates is known, from the light projecting unit of the optical device to the holding plate (or to the subject) The distance is also revealed.

(Processing flow)
Next, the flow from the implementation of photoacoustic imaging in Example 2 to the display of the photoacoustic image will be described with reference to the flow of FIG. However, steps common to the flow shown in FIG. 2A in the first embodiment are denoted by the same reference numerals and description thereof is omitted. Photoacoustic signal acquisition is performed in the same manner as in FIG.

In FIG. 4, in order to start this flow in step S400, it is necessary for the user (worker) to confirm the display of the state display unit 109 and determine that the holding state of the subject 100 is appropriate. is there. The worker makes a determination based on various criteria as in the first embodiment.
Then, the operator performs holding by moving the holding plate driving mechanism 102 appropriately while operating the breast by a technique. At this time, it is also confirmed whether both the subject detection sensor 103 and the light projection sensor 300 are reacting. Information necessary for this confirmation is displayed on the state display unit 109 at a position where the operator can visually recognize the procedure while performing the procedure. Thereby, preparation is completed and photoacoustic imaging is started.

  In step S <b> 401, the control unit 108 receives the states of the subject detection sensor 103 and the light projection sensor 300. When the subject detection sensor 103 and the light projection sensor 300 are both reacting (S401 = YES), the imaging is continued. If the subject detection sensor 103 and the light projection sensor 300 are not reacting on either side (S401 = NO), the imaging is terminated (step S204). Here, when the subject detection sensor 103 or the light projecting sensor 300 is not responding, the imaging start in S400 may be disabled.

  The photoacoustic signal acquisition in step S202 is performed in the same procedure as the flow in FIG. Steps S203 and S204 are the same as in the first embodiment. A photoacoustic image is generated and displayed according to the above flow.

  Also in the present embodiment, as in the first embodiment, the advantage that the insertion adjustment of the subject is performed well can be enjoyed. In addition, according to the present embodiment, it is possible to realize an irradiation light amount that does not exceed MPE without causing a decrease in contrast. Furthermore, the subject can be held while checking the state of the light projecting sensor. As a result, it is possible to perform an appropriate procedure in accordance with the state of holding the subject and the safety state from the viewpoint of the amount of irradiation light, and good photoacoustic imaging can be performed. In other words, the state of insertion of the subject into the device varies depending on the size and shape of the subject, but by performing the procedure while confirming (visually confirming) the detection result of the light projecting sensor, the light amount satisfies the safety standard. Can be realized.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not restricted to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  101A: holding plate, 101B: holding plate, 102: holding plate driving mechanism, 103: subject detection sensor, 104: light source, 105: optical device, 106: probe, 107: probe driving mechanism, 108: control 109, status display unit, 110: information processing unit

Claims (4)

An object information acquisition apparatus that receives acoustic waves propagating through an object and acquires characteristic information of the object,
A pair of holding members positioned opposite to each other and sandwiching the subject;
Light irradiation means for irradiating the subject with light;
Subject detection means for detecting the position of the subject between the pair of holding members;
State display means for displaying information on the position of the subject detected by the subject detection means,
The object information acquisition apparatus according to claim 1, wherein the state display unit is mounted at a position where an operator can visually recognize the object when the object is held between the pair of holding members. The light irradiating means irradiates the subject with light through one of the pair of holding members,
A distance detection means for detecting a distance between the light irradiation means and a holding member on the side irradiated with light from the light irradiation means;
The object information acquiring apparatus according to claim 1, wherein the state display unit displays information detected by the distance detection unit. The subject according to claim 2, wherein the distance detection means is a light detection sensor located between the light irradiation means and a holding member on a side irradiated with light from the light irradiation means. Information acquisition device. An object information acquisition apparatus that receives acoustic waves propagating through an object and acquires characteristic information of the object,
A pair of holding members positioned opposite to each other and sandwiching the subject;
Light irradiation means for irradiating the subject with light;
Subject detection means for detecting whether the subject exists between the pair of holding members;
State display means for displaying information on the presence of the object detected by the object detection means,
The object information acquisition apparatus according to claim 1, wherein the state display unit is mounted at a position where an operator can visually recognize the object when the object is held between the pair of holding members.

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