JP6000591B2 - Subject information acquisition apparatus and control method thereof - Google Patents

Description

  The present invention relates to a subject information acquisition apparatus and a control method thereof.

  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. 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. A technique of tomography using such a photoacoustic effect is 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.

  In order to obtain an accurate measurement result in photoacoustic tomography, the desired intensity and distribution of measurement light are required. However, since the photoacoustic imaging apparatus uses a light source such as a laser to generate measurement light, the measurement light changes due to deterioration of the light source over time. Therefore, regular maintenance is required.

  Patent Document 1 describes remote maintenance of medical devices. Further, a technique is described that enables maintenance for a predetermined function even when the medical device is in operation.

JP 2008-073448 A

The photoacoustic imaging apparatus is equipped with a safety mechanism so that light can be emitted from a light source such as a laser only in a state where predetermined requirements for safety are satisfied. This mechanism ensures the safety of the user.
On the other hand, when performing maintenance, there are cases where it is desired to irradiate light intentionally even in a state where the requirements required by the safety mechanism cannot be satisfied or in a state where the requirements are not satisfied.

  However, in the prior art, there was no means for invalidating the safety mechanism during maintenance. Therefore, in a state where the requirements for the safety mechanism are not satisfied, there is a problem that the maintenance function accompanied by light irradiation cannot be executed. In addition, other safety mechanisms, such as a mechanism that makes it impossible to move a probe, an optical device, or the like when a work opening is open, may be desired to be released during maintenance.

The present invention has been made in view of the above problems, and an object of the present invention is to enable maintenance even in a state where the requirements of the safety mechanism are not satisfied in an apparatus that performs photoacoustic imaging.

  The present invention employs the following configuration. That is, a light source that irradiates a subject with light by an optical device, a probe that receives an acoustic wave generated from the subject irradiated with light, and the optical device and the probe that move along the subject And a safety means for prohibiting light irradiation from the light source when the safety requirements of the light source are not satisfied and prohibiting movement by the moving means when the safety requirements of the moving means are not satisfied A subject information acquisition device having a mechanism and a control unit, wherein the subject information acquisition device operates in a normal mode for receiving an acoustic wave from the subject and a maintenance mode for performing maintenance, The control means disables at least one of the functions of the safety mechanism prohibiting the operation of the light source and the moving means in the maintenance mode. A subject information obtaining apparatus according to.

The present invention also employs the following configuration. That is, a light source that irradiates a subject with light by an optical device, a probe that receives an acoustic wave generated from the subject irradiated with light, and the light source when the safety requirements of the light source are not satisfied A subject information acquisition apparatus having a safety mechanism that prohibits light irradiation and control means, further comprising means for detecting an error of the subject information acquisition apparatus, the subject information acquisition apparatus comprising: operating in a normal mode for receiving an acoustic wave from the object, and a maintenance mode for performing maintenance, the control means, in the maintenance mode, intended to disable the function of the safety mechanism to prohibit the operation of the light source And, in the normal mode, the control means permits light irradiation from the light source when the error is not detected, and in the maintenance mode, The ability to inhibit the operation of the serial light source, a detection result of said error is a subject information obtaining apparatus, characterized by independently invalidated.

  The present invention also employs the following configuration. That is, a light source that irradiates a subject with light by an optical device, a probe that receives an acoustic wave generated from the subject irradiated with light, and the optical device and the probe that move along the subject And a safety means for prohibiting light irradiation from the light source when the safety requirements of the light source are not satisfied and prohibiting movement by the moving means when the safety requirements of the moving means are not satisfied A control method for a subject information acquiring apparatus having a mechanism and a control means, wherein the control means performs maintenance on the subject information acquiring apparatus and a normal mode for receiving an acoustic wave from the subject. A step of determining whether to operate in a maintenance mode; and the control means in the maintenance mode, wherein the safety mechanism controls the operation of the light source and the moving means. Of the ability to stop, a control method of an object information acquiring apparatus, comprising the steps of: disabling at least one function.

The present invention also employs the following configuration. That is, a light source that irradiates a subject with light by an optical device, a probe that receives an acoustic wave generated from the subject irradiated with light, and the light source when the safety requirements of the light source are not satisfied The object information acquisition apparatus has a safety mechanism that prohibits light irradiation and a control unit, and the control unit receives the object information acquisition apparatus and receives an acoustic wave from the object. Determining whether to operate in a normal mode or a maintenance mode in which maintenance is performed; and the step of disabling the function of the safety mechanism prohibiting the operation of the light source in the maintenance mode by the control means; have the object information acquiring apparatus comprises a means for detecting the error of the object information acquiring apparatus further wherein, in the normal mode, the d Over the permitted light irradiation from the light source when it is not detected, the maintenance mode, the function of inhibiting the operation of said light source, characterized in that independently of disabling the detection result of the error It is a control method of the subject information acquisition apparatus.

  According to the present invention, in a device that performs photoacoustic imaging, it is possible to perform maintenance even when the requirements for the safety mechanism are not satisfied.

The figure which shows the structure of a photoacoustic imaging device. The figure which shows the relationship between the various modes in Example 1, and a maintenance function. The figure which shows the relationship between the mode switch in Example 1, and various modes. 5 is a flowchart at the time of maintenance in the first embodiment. FIG. 6 is a diagram illustrating a function of a mode switch in the second embodiment. 9 is a flowchart at the time of maintenance 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 present invention can also be understood as a method for controlling a subject information acquiring apparatus having the following configuration.

  The photoacoustic imaging apparatus according to the present invention has a photoacoustic effect of receiving acoustic waves generated in a subject by irradiating the subject with light (electromagnetic waves) and acquiring characteristic information in the subject as image data. Includes equipment used. The characteristic information acquired at this time is the source distribution of acoustic waves generated by light irradiation, the initial sound pressure distribution in 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 in the subject.
The subject imaging referred to in the present invention is an act of irradiating a subject with light to receive an acoustic wave, an act of generating characteristic information based on the received acoustic wave, and converting the characteristic information into a display format desired by the user. This includes the act of converting it into image data.

<Example 1>
As a basic embodiment of the present invention, the configuration and operation of a system according to the present invention will be described with reference to the drawings.

(Device configuration)
As shown in FIG. 1, the photoacoustic imaging apparatus according to the present embodiment includes a holding plate 101 </ b> A and a holding plate 101 </ b> B as holding units that hold the subject 100. Furthermore, the photoacoustic imaging apparatus includes an object detection sensor 102 that detects whether an object is inserted between the holding plates, a light source 103 that generates measurement light, and an optical device 104 that converts the generated measurement light into a desired form. .

  Furthermore, the photoacoustic imaging apparatus includes an acoustic wave probe 105 (hereinafter also referred to as a probe) that detects a photoacoustic wave that is generated in the light absorbing material 111 by light irradiation and propagates through the subject, and a probe. A probe driving mechanism 106 that moves the position of the child 105 is provided. Furthermore, the photoacoustic imaging apparatus has a mode switch 107 for switching between the normal mode and the maintenance mode.

Further, the photoacoustic imaging apparatus includes a control unit 108 that controls the light source 103, the optical apparatus 104, the probe 105, and the probe driving mechanism 106. The control unit 108 also receives the states of the subject detection sensor 102 and the mode changeover switch 107.
Further, the photoacoustic imaging apparatus receives the acquired photoacoustic wave from the control unit 108 and generates a photoacoustic wave image or the like in the subject, and a display unit that displays the generated photoacoustic wave image or the like 110.

  In FIG. 1, a subject 100 to be imaged is held and fixed from both sides by a holding unit made up of a pair of two holding plates. In order to change the holding distance and pressure, the holding positions of the holding plate 101A and the holding plate 101B constituting the holding unit are controlled by a holding plate driving mechanism (not shown). When there is no need to distinguish between the holding plate 101A and the holding plate 101B, they are collectively referred to as the holding plate 101.

  By fixing the subject 100 between the holding plate 101 and the apparatus, the measurement error due to the movement of the subject 100 can be reduced. Since the holding plate 101B is located on the optical path of the measurement light, the holding plate 101B preferably has a high transmittance with respect to the measurement light. In addition, the holding plate 101A is preferably a member having high acoustic matching with the probe 105. As the holding plate, for example, a member such as polymethylpentene used in an ultrasonic diagnostic apparatus or the like is used.

  In order to detect whether or not the subject 100 exists between the holding plates, a subject detection sensor 102 is mounted. If light irradiation is performed in a state where the subject 100 does not exist between the holding plates, light may leak from the subject (for example, breast) insertion port between the holding plates, and the predetermined requirements for ensuring safety may not be satisfied. For example, there is a risk that a laser leaking from the insertion port may enter the eyes of the user. In order to prevent such danger, the object detection sensor 102 exists. That is, if the subject detection sensor 102 does not detect the presence of the subject, the safety mechanism prevents the light from being irradiated. Any object detection sensor 102 may be used as long as it can detect the object, such as a light detection sensor or a pressure sensor.

  Such a safety mechanism is realized as a system in which each member constituting the photoacoustic imaging apparatus is interlocked. For example, a control unit that prohibits execution of light irradiation based on the result of object detection, a light source or an optical device that stops light irradiation according to an instruction from the control unit, a shutter that blocks light from the light source or the optical device, etc. Various members constitute a safety device. In addition, a memory that stores safety conditions for prohibiting execution of light irradiation may be included in the safety mechanism.

  The measurement light emitted to the subject 100 is generated by the light source 103. In general, the light source 103 is a solid-state laser (for example, a Yttrium-Aluminium-Garnet laser or a Titanium-Sapphire laser) capable of emitting a pulse having a center wavelength in the near-infrared region.

  The wavelength of the measurement light is selected according to a light absorbing substance (for example, hemoglobin, glucose, cholesterol, etc.) in the subject 100 to be imaged. Preferably, the wavelength is between 530 nm and 1300 nm. For example, hemoglobin in breast cancer new blood vessels to be imaged in breast examination 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 of hemoglobin 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.

  The optical device 104 for irradiating the subject 100 with measurement light from the light source 103 in a desired shape includes an optical system such as a lens, a mirror, and an optical fiber. In addition, by providing a scanning mechanism that scans the light irradiation position with respect to the holding plate 101, a wide range of the subject can be measured. Any optical system may be used as long as measurement light emitted from the light source 103 is irradiated on the subject 100 in a desired shape.

When measurement light generated by the light source 103 is irradiated onto the subject 100 via the optical device 104, the light absorbing material 111 in the subject absorbs light and emits photoacoustic waves. In this case, the light absorbing material 111 corresponds to the sound source.

  The probe 105 receives a photoacoustic wave generated by the light absorbing material 111 and converts it into an electric signal. The photoacoustic wave generated from the living body is usually an ultrasonic wave of 100 KHz to 100 MHz. Therefore, a probe capable of receiving the above frequency band is used as the probe 105. Any probe can 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 a plurality of elements are arranged one-dimensionally or two-dimensionally, photoacoustic waves can be detected at a plurality of locations at the same time, and the detection time can be shortened. The influence of vibration etc. can be reduced.

  In the present embodiment, the subject 100 is irradiated with measurement light on the front surface of the probe 105. Therefore, the optical device 104 and the probe 105 are arranged at positions facing each other with the subject 100 interposed therebetween. Then, scanning control is performed in which the optical device 104 and the probe driving mechanism 106 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 mode switch 107 is for switching the operation mode of the photoacoustic imaging apparatus between the normal mode and the maintenance mode. Although details will be described later, a plurality of maintenance modes may be prepared. In that case, a plurality of maintenance modes can be handled by installing a plurality of mode changeover switches 107. As the mode switch 107, for example, a switch that switches ON / OFF by pressing, or a sensor that detects contact or load can be used. In addition, any switch may be used as long as the user's intention can be transmitted to the control unit. Alternatively, a switch that electrically switches control in response to an instruction from the control unit 108 may be used.

  The control unit 108 amplifies the electrical signal converted from the photoacoustic wave received by the probe 105 and converts the analog signal (analog electrical signal) into a digital signal (digital electrical signal). The control unit 108 also performs integration processing of digital signals for noise reduction. The control unit 108 also controls the light source 103, the optical device 104, the probe 105, and the probe drive mechanism 106.

  Further, the control unit 108 receives the state of the subject detection sensor 102 and the mode changeover switch 107. Based on the received state of the mode changeover switch 107, the state of the system of the photoacoustic imaging apparatus (hereinafter also referred to as the system) is shifted between the normal mode and the maintenance mode. When there are a plurality of maintenance modes, which one to use is determined according to the state of the mode switch. Furthermore, the state of the photoacoustic imaging apparatus is monitored, and if an error has occurred, the system is shifted to the error state.

  The integration process between digital signals refers to repeatedly measuring the same part of the subject 100 and performing an addition averaging process. This is done to reduce system noise and improve the S / N ratio of the photoacoustic wave signal. At this time, it is desirable that the necessary number of integration processes is set based on preliminary measurement.

  Scanning control in which the optical device 104 and the probe driving mechanism 106 are linked is performed while maintaining the positional relationship between the optical device 104 and the probe 105. By performing two-dimensional scanning on the subject 100 with the optical device 104 and the probe driving mechanism 106 and performing measurement at each scanning position, even the small probe 105 can acquire photoacoustic waves from a wide imaging region. It becomes like this. For example, when the subject is a breast, a full-breast photoacoustic wave image can be captured.

  The information processing unit 109 generates a photoacoustic wave image based on the photoacoustic wave signal received from the control unit 108 and displays it on the display unit 110. The photoacoustic wave image is an image obtained by visualizing desired characteristic information (subject information) in the subject. Image data is generated based on the characteristic information and transmitted to the display unit. As the information processing unit 109, 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. For example, a display device provided with a liquid crystal panel or the like can be used as the display unit 110.

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

(Shooting conditions)
Next, conditions for enabling the photoacoustic imaging apparatus to perform imaging will be described. In order to make the apparatus capable of photographing, the following two conditions must be satisfied.
Condition (1): No error has occurred from the photoacoustic imaging apparatus.
Condition (2): The requirement of the safety mechanism mounted on the photoacoustic imaging apparatus is satisfied.

  The error shown in the condition (1) is notified and recognized when an abnormality occurs in the apparatus. Examples of the error include damage to the probe 105, the information processing unit 109 not installed, or a communication failure with the information processing unit 109. The control unit 108 recognizes the occurrence of an error by receiving an error notification from each block or by detecting an error in each block or communication path using a sensor.

  The safety mechanism in the condition (2) is a mechanism mounted for safely irradiating light, and the subject detection sensor 102 corresponds to this embodiment. In this embodiment, the function of the safety mechanism prohibits light irradiation under a predetermined condition. The safety mechanism also prohibits movement of the probe and optical device under certain conditions. As for the safety mechanism, various safety mechanisms are expected to be mounted depending on the device configuration and the like, and are not limited to the mechanisms described in this embodiment. Further, the functions of the safety mechanism are expected to be various functions depending on the device configuration and the like, and are not limited to the functions described in this embodiment.

(Maintenance function)
A maintenance function of the photoacoustic imaging apparatus will be described.

First, the optical maintenance function will be described.
The measurement light emitted from the light source 103 changes due to the influence of aging degradation of the light source. In addition, when the mirror mounted on the optical device 104 moves due to vibration or the like, a change occurs in the light distribution of the measurement light applied to the subject. In order to confirm whether or not these changes have occurred, an optical maintenance function is prepared. A method for realizing the optical maintenance function is, for example, as follows.

Step (1): A two-dimensional photosensor is disposed instead of the subject so as to face the holding plate 101B on the light irradiation side, and is connected to the control unit 108.
Step (2): The measurement light emitted from the light source is received by a two-dimensional optical sensor disposed between the holding plates, and the acquired light quantity is transmitted to the control unit.
Step (3): The amount of light received by the control unit 108 is transmitted to the information processing unit 109, and the information processing unit creates a light distribution from the amount of light and causes the display unit 110 to display the light distribution.
Step (4): From the light distribution, the state of deterioration of the light source over time, the installation change of the optical device 104 such as a mirror, etc. are confirmed.

  In step (4), in addition to the user confirming the display unit, the control unit may automatically analyze the light distribution according to program control and perform maintenance.

  In such an optical maintenance function, light is emitted from a light source, and a maintainer (maintenance person for maintenance) may perform an operation such as adjustment at that time. On the other hand, in consideration of the fact that high-energy laser light is generally generated during light irradiation, from the viewpoint of safety, for example, there is a gap in the working opening or the subject is held correctly. The condition is set such that light is not irradiated in a state where there is no vibration or a state where there is some vibration. Therefore, it may happen that the requirements of the safety mechanism are not satisfied due to the adjustment operation performed by the maintainer or the absence of the subject.

Next, the stage maintenance function will be described.
The optical device 104 and the probe driving mechanism 106 gradually change in operation speed or the like due to aging or the like. However, unless the optical device 104 and the probe driving mechanism 106 are scanned and controlled in conjunction with each other, photoacoustic data cannot be acquired at the correct position. In order to solve this problem, a stage maintenance function for periodically operating the optical device 104 and the probe driving mechanism 106 is prepared.

  In order to realize the stage maintenance function, for example, a mechanism for measuring the speed of the optical device 104 and the probe driving mechanism 106 and a mechanism for measuring the relative positions of each other are provided. Then, by measuring the speed and relative position of the optical device and the probe drive mechanism in the absence of the subject, it is possible to confirm the change in speed due to aging of each component.

  In such a stage maintenance function, the optical device and the probe are mechanically scanned, and the maintainer may perform operations such as adjustment during the scanning. On the other hand, in general, when an optical device or a probe is scanned, there is a gap in the working opening, a state in which the subject is not properly held, or some vibration from the viewpoint of safety. A condition that scanning is not performed in the state is set. Therefore, it may happen that the requirements of the safety mechanism are not satisfied due to the adjustment operation performed by the maintainer or the absence of the subject.

  Further, in the stage maintenance function, it may be possible to confirm whether or not the photographing in which the optical device and the probe are linked is performed correctly. That is, it is confirmation whether light irradiation from the light source is performed in accordance with the timing of movement and stop of the optical device and the probe. If such timing control is not properly performed, an acoustic wave derived from the subject cannot be accurately received, which may lead to an error in characteristic information or mixing of artifacts in an image in the subject. . However, as will be described later, in this embodiment, optical maintenance is impossible in the maintenance mode for local workers, and optical maintenance is possible only in the maintenance mode for developers. This is based on the fact that maintenance involving light irradiation has a higher safety standard than other actions, and the stage maintenance function in such a case preferably does not involve light irradiation.

  When the system of the photoacoustic imaging apparatus performs the maintenance function as described above, unlike the case of acquiring normal object information, light irradiation is performed without holding the object between the holding plates. Is called. As a result, the object detection sensor notifies the control unit of the detection result that there is no object. Here, if the safety requirement required by the safety mechanism is that the subject is held, light irradiation cannot be performed without the subject.

  The maintenance function of the photoacoustic imaging apparatus has been described above. However, the maintenance function is not limited to these. Various maintenance functions can be installed depending on the device configuration and the like, and a measuring method corresponding to each maintenance function can be used.

(Device mode)
Next, modes of the photoacoustic imaging apparatus will be described.
The modes of the photoacoustic imaging apparatus are roughly classified into a normal mode and a maintenance mode. The normal mode is a mode used by a device user such as a doctor to perform a normal diagnosis. The maintenance mode is a mode used when the maintainer performs maintenance. Furthermore, a plurality of modes are prepared for the maintenance mode according to the level of the maintainer, such as a mode for local workers and a mode for developers.

  FIG. 2 shows a list of functions that can be used for each mode. In the field worker mode, only the stage maintenance function can be used. All maintenance functions are available in developer mode. In this way, by limiting the functions that can be used for each mode, it is possible to prevent an operation error by a maintainer or an apparatus user. Various maintenance functions can be provided according to the configuration of the photoacoustic imaging apparatus, and the types of maintenance modes are not limited to those shown in the figure.

  Next, the relationship between the state of the mode switch 107 and the maintenance mode will be described with reference to FIG. FIG. 3 shows a method of switching between modes by installing two mode changeover switches when the maintenance mode is a mode for a local worker and a mode for a developer. The two mode change switches are referred to as mode change switches A and B, respectively.

  The state in which both the mode selector switches A and B are turned off is referred to as a normal mode. A state in which the mode changeover switch A is turned on and the mode changeover switch B is turned off is set as a field worker mode. The mode change switch A is turned OFF and the mode change switch B is turned ON is set as a developer mode.

  Here, when there are three maintenance modes, the state where both the mode change-over switches A and B are turned on may be used. If the maintenance mode is 4 modes or more, three or more mode change-over switches may be prepared. Here, the maintenance mode may be switched by any switch as long as one state can be selected from a plurality of stages. Alternatively, other than a simple switch, an input device (not shown) may be provided in the information processing unit 109, and password input or the like may be performed from the input device.

Next, the flow from the execution to the end of the maintenance function will be described with reference to the flow of FIG.
(Step S400) Maintenance is started after the user presses the mode switch 107.
(Step S401) The state of the mode changeover switch 107 is transmitted to the control unit.

  (Step S402) The control unit 108 receives the state of the mode changeover switch 107, and shifts the system to the corresponding maintenance mode. At this time, any errors that have occurred up to that point are cleared. In addition, after the transition to the maintenance mode, the error and the safety mechanism are invalidated. This measure makes it possible to execute the maintenance function even in an error state or a state where the safety mechanism is not satisfied.

(Step S403) All necessary maintenance functions are executed according to the system after the transition. At this time, if an operation by the maintainer is necessary, maintenance can be performed interactively through image output or sound output, and if automatic maintenance by the apparatus is possible, it can be followed.
(Step S404) All the mode changeover switches 107 are turned OFF, and the control unit 108 shifts the system to the normal mode. Also enable error and safety mechanisms.
Maintenance is performed as described above, and the flow ends in step S405.

  According to the present embodiment, even when the requirements of the safety mechanism are not satisfied (for example, the state where the subject is not detected) or the error is recognized, the maintenance function of the apparatus, particularly the light irradiation is performed. The accompanying maintenance can be performed. As a result, the maintainability of the apparatus is improved, and diagnosis can be performed in a good state.

  Further, according to the present embodiment, since the functions that can be executed for each maintenance mode are limited, only the operation according to the authority of the maintainer is performed. As a result, it is possible to prevent an operation error caused by the maintainer and unnecessary execution of the maintenance function.

<Example 2>
In the second embodiment, there is only one type of maintenance mode, and a case where a function that can be used is determined according to an error state and a state of a safety mechanism will be described. The configuration of the photoacoustic imaging apparatus in the present embodiment is basically the same as that in the first embodiment, and the control and processing flow by the control unit is different.

First, the state of the mode changeover switch 107, error, and invalidation of the safety mechanism will be described with reference to FIG.
When the mode switch A is ON, the error is invalidated, the error that has occurred so far is cleared, and even if an error occurs thereafter, it is ignored. When the mode switch B is ON, the safety mechanism is invalidated. Therefore, when both the mode change-over switches A and B are turned on, both the error state and the safety mechanism are invalidated.
When the mode change switch A or the mode change switch B is ON, the apparatus is in the maintenance mode.

  Next, the relationship between the maintenance function, the error state, and the safety mechanism state in this embodiment will be described. In the first embodiment, safety is ensured by subdividing the maintenance mode and restricting operations that can be executed according to authority, but there is a lack of flexibility. On the other hand, in the present embodiment, since the maintainer switches the restriction of the safety mechanism according to the desired control, it is possible to perform appropriate processing according to the actual state of the apparatus.

In the present embodiment, the usage condition of the optical maintenance function is that no error has occurred and that the requirements required by the safety mechanism are satisfied. With this condition, safety can be ensured even with light irradiation.
In the present embodiment, the use condition of the stage maintenance function is that no error has occurred. If no error has occurred, it is considered that there is no problem in the operation of the apparatus even if the safety mechanism is not satisfied.

  Depending on the configuration of the photoacoustic imaging apparatus and the like, the use conditions of each maintenance function may change. Therefore, the relationship between the maintenance function, the error, and the safety mechanism is not limited to the relationship described in the present embodiment. The relationship can be determined depending on whether various safety mechanisms need to be operating when performing maintenance.

Next, the relationship between the maintenance function and the mode change switch will be described.
When the mode switch A is ON and the mode switch B is OFF, the stage maintenance function can be used. When both switches A and B are ON, the stage maintenance function and the optical maintenance function can be used.

  Next, the flow from the execution to the end of the maintenance function will be described with reference to the flow of FIG. However, steps S400 to S401 and S403 to S405 common to the first embodiment are denoted by the same reference numerals and description thereof is omitted. In this embodiment, S600 is executed instead of step S402.

  (Step S600) The control unit 108 receives the state of the mode switch 107. Then, according to the received state, as described above, the error or the safety mechanism is invalidated, or both are invalidated, and the mode is changed to the maintenance mode.

  According to the present embodiment, the usable maintenance function is determined by the error or the invalid state of the safety mechanism. As a result, errors and safety mechanisms are appropriately invalidated according to the level of the maintainer, so that the safety of maintenance work can be improved.

  100: subject, 101A: holding plate, 101B: holding plate, 102: subject detection sensor, 103: light source, 104: optical device, 105: probe, 106: probe drive mechanism, 107: mode switch 108: Control unit 109: Information processing unit 110: Display unit 111: Light absorbing material

Claims (15)

A light source that irradiates a subject with light by an optical device;
A probe for receiving an acoustic wave generated from a subject irradiated with light;
Moving means for moving the optical device and the probe along a subject;
A safety mechanism that prohibits light irradiation from the light source when safety requirements of the light source are not satisfied, and prohibits movement by the moving means when safety requirements of the moving means are not satisfied;
Control means;
A subject information acquisition apparatus comprising:
The subject information acquisition apparatus operates in a normal mode for receiving an acoustic wave from a subject and a maintenance mode for performing maintenance,
In the maintenance mode, the control unit invalidates at least one of the functions of the safety mechanism for prohibiting the operation of the light source and the moving unit. The maintenance mode includes a plurality of maintenance modes,
The subject information acquiring apparatus according to claim 1, wherein the control unit determines which function of the safety mechanism is invalidated according to which maintenance mode is executed. 3. The subject information acquiring apparatus according to claim 2, wherein which of the plurality of maintenance modes is executed is determined according to a level of a maintenance person.   An object detection means for detecting the presence of the object;
  The safety mechanism operates when the subject detection means does not detect the presence of the subject.
The object information acquiring apparatus according to claim 1, wherein the object information acquiring apparatus is an object information acquiring apparatus.   Further comprising means for detecting an error in the subject information acquiring apparatus,
  In the normal mode, the control means performs light irradiation from the light source and the moving means when the safety requirements of the light source and the moving means are satisfied and the error is not detected. Allow movement
The object information acquiring apparatus according to claim 1, wherein the object information acquiring apparatus is an object information acquiring apparatus.   Further comprising means for detecting an error in the subject information acquiring apparatus,
  In the normal mode, the control means permits the light irradiation from the light source when the error is not detected, and prohibits the operation of the light source in the maintenance mode. Disable regardless
The object information acquiring apparatus according to claim 1, wherein the object information acquiring apparatus is an object information acquiring apparatus. A light source that irradiates a subject with light by an optical device;
A probe for receiving an acoustic wave generated from a subject irradiated with light;
A safety mechanism for prohibiting light irradiation from the light source if the safety requirements of the light source are not met,
Control means;
A subject information acquisition apparatus comprising:
It further has means for detecting an error in the subject information acquisition apparatus,
The subject information acquisition apparatus operates in a normal mode for receiving an acoustic wave from a subject and a maintenance mode for performing maintenance,
The control means disables the function of the safety mechanism prohibiting the operation of the light source in the maintenance mode , and
In the normal mode, the control means permits the light irradiation from the light source when the error is not detected, and prohibits the operation of the light source in the maintenance mode. <Desc / Clms Page number 15> An object information acquisition apparatus characterized by invalidating regardless of the above .   An object detection means for detecting the presence of the object;
  The safety mechanism operates when the subject detection means does not detect the presence of the subject.
The subject information acquiring apparatus according to claim 7. A light source that irradiates light onto the subject by the optical device, a probe that receives an acoustic wave generated from the subject irradiated with light, and a movement that moves the optical device and the probe along the subject. And a safety mechanism that prohibits light irradiation from the light source when the safety requirements of the light source are not satisfied, and prohibits movement by the moving means when the safety requirements of the moving means are not satisfied Control means;
A method for controlling a subject information acquisition apparatus comprising:
Determining whether the control means operates the subject information acquisition apparatus in a normal mode for receiving an acoustic wave from the subject or a maintenance mode for performing maintenance;
Invalidating at least one of the functions of the safety mechanism prohibiting the operation of the light source and the moving means in the maintenance mode;
A method for controlling a subject information acquiring apparatus, comprising:   The maintenance mode includes a plurality of maintenance modes,
  In the invalidating step, the control means determines which function of the safety mechanism is invalidated according to which maintenance mode is executed.
The method for controlling an object information acquiring apparatus according to claim 9.   The subject information acquisition apparatus further includes subject detection means for detecting the presence of the subject,
  The safety mechanism operates when the subject detection means does not detect the presence of the subject.
The control method of the subject information acquiring apparatus according to claim 9 or 10.   The subject information acquisition apparatus further includes means for detecting an error in the subject information acquisition apparatus,
  In the normal mode, the control means performs light irradiation from the light source and the moving means when the safety requirements of the light source and the moving means are satisfied and the error is not detected. Allow movement
The control method of the subject information acquiring apparatus according to claim 9 or 10.   The subject information acquisition apparatus further includes means for detecting an error in the subject information acquisition apparatus,
  In the normal mode, the control means permits the light irradiation from the light source when the error is not detected, and prohibits the operation of the light source in the maintenance mode. Disable regardless
The control method of the subject information acquiring apparatus according to claim 9 or 10. A light source for irradiating the subject with light by an optical device, a probe for receiving an acoustic wave generated from the subject irradiated with the light, and light from the light source when safety requirements of the light source are not satisfied A safety mechanism for prohibiting irradiation, a control means,
A method for controlling a subject information acquisition apparatus comprising:
Determining whether the control means operates the subject information acquisition apparatus in a normal mode for receiving an acoustic wave from the subject or a maintenance mode for performing maintenance;
The control means invalidating a function of the safety mechanism prohibiting the operation of the light source in a maintenance mode;
Have
The subject information acquisition apparatus further includes means for detecting an error in the subject information acquisition apparatus,
In the normal mode, the control means permits the light irradiation from the light source when the error is not detected, and prohibits the operation of the light source in the maintenance mode. The method for controlling the subject information acquiring apparatus, wherein the method is invalidated independently .   The subject information acquisition apparatus further includes subject detection means for detecting the presence of the subject,
  The safety mechanism operates when the subject detection means does not detect the presence of the subject.
The control method of the subject information acquiring apparatus according to claim 14.

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