JP2024108564A - Medical image diagnostic apparatus, medical information processor, and medical image diagnosis method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce burden on a subject when examining a blood vessel.

SOLUTION: A medical image diagnostic apparatus is provided with an acquisition part, a setting part, and an imaging part. The acquisition part acquires blood information related to a change in hemoglobin quantity contained in blood in the blood vessel at a first part of a subject. The setting part sets an imaging condition related to contrast imaging of a second part of the subject on the basis of the blood information. The imaging part performs contrast imaging on the basis of the imaging condition.

SELECTED DRAWING: Figure 2

COPYRIGHT: (C)2024,JPO&INPIT

Description

The embodiments disclosed in this specification and the drawings relate to a medical image diagnostic device, a medical information processing device, and a medical image diagnostic method.

In examinations using medical imaging diagnostic equipment such as X-ray computed tomography equipment (X-ray CT equipment), imaging is performed using a contrast agent to determine the state of blood circulation in the affected area, as well as the state of tissue and functional status. A vascular contrast agent (hereafter simply referred to as contrast agent) is injected into the blood vessels of the patient (subject) using a contrast agent injection device (injector) or manually with a syringe. The contrast agent injected into the subject's blood vessels reaches the affected area (examination site) via the bloodstream. The imaging device takes images at the desired timing, such as when the contrast agent arrives, when the contrast peaks, or when it is escaping.

For example, in CT scans using contrast agents, imaging is performed using methods such as bolus tracking and test injection to optimize the contrast timing to suit the subject's condition. With the bolus tracking method, after contrast agent is injected, intermittent imaging is performed at a low dose to monitor the arrival of the contrast agent and control the start time of the actual imaging (main scan). With the test injection method, a small amount of contrast agent is test injected before the main scan and monitored while intermittent imaging is performed to confirm the arrival of the contrast agent and the time to peak in advance, and then the start time of the main scan is decided.

The contrast agents used in the bolus tracking and test injection methods are made from substances that have little effect on the human body, but are contraindicated for people with weakened functions to expel contrast agents. In addition, the X-rays used in CT scans are invasive to the human body. Therefore, in clinical practice, it is desirable to reduce the amount of both contrast agent and X-ray exposure.

In addition, both the bolus tracking method and the test injection method require the use of contrast agents and scans required for diagnostic imaging, as well as exposure to radiation and the use of additional contrast agents to time the scans, placing an excessive burden on the subject compared to regular CT scans.

Furthermore, because the monitoring position is usually fixed at one location, even if imaging is started at the right time, if the imaging distance is long, the scan position may be moved and the scan may overtake the contrast agent. As a result, imaging cannot be performed at the correct time, and there is a risk of the subject being subjected to an unnecessary burden due to reexamination.

Japanese Patent Application Publication No. 6-277202

One of the problems that the embodiments disclosed in this specification and the drawings attempt to solve is to reduce the burden on the subject when performing blood vessel examinations. However, the problems that the embodiments disclosed in this specification and the drawings attempt to solve are not limited to the above problem. Problems that correspond to the effects of each configuration shown in the embodiments described below can also be positioned as other problems.

The medical image diagnostic apparatus according to the embodiment includes an acquisition unit, a setting unit, and an imaging unit. The acquisition unit acquires blood information related to changes in the amount of hemoglobin contained in blood in blood vessels in a first region of a subject. The setting unit sets imaging conditions related to contrast imaging of a second region of the subject based on the blood information. The imaging unit performs contrast imaging based on the imaging conditions.

FIG. 1 is a block diagram showing a medical image diagnostic apparatus according to an embodiment, and a blood information acquisition apparatus and an injector connected to the medical image diagnostic apparatus. FIG. 2 is a block diagram showing an example of the configuration of the X-ray CT apparatus according to the first embodiment. FIG. 3 is a flowchart showing a first example of the X-ray CT apparatus according to the first embodiment. FIG. 4 is an explanatory diagram illustrating an example of the installation position of the optical imaging device in the first embodiment. FIG. 5 is a schematic diagram illustrating a setup situation around a subject in the first embodiment. FIG. 6 is a diagram illustrating an example of a display screen during test injection in the first embodiment. FIG. 7 is a diagram illustrating an analysis result of the h-TDC in the first embodiment. FIG. 8 is a diagram illustrating an example of a display screen during contrast imaging in the first embodiment. FIG. 9 is a flowchart showing a second example of the X-ray CT apparatus according to the first embodiment. FIG. 10 is a schematic diagram illustrating a setup situation around a subject in the second embodiment. FIG. 11 is a diagram illustrating an example of a display screen during contrast imaging using bolus tracking in the second embodiment. FIG. 12 is a flowchart showing a third example of the X-ray CT apparatus according to the first embodiment. FIG. 13 is a schematic diagram illustrating a setup situation around a subject in the third embodiment. FIG. 14 is a diagram illustrating an example of an analysis result of a plurality of h-TDCs in the third embodiment. FIG. 15 is a block diagram showing an example of the configuration of a magnetic resonance imaging apparatus according to the second embodiment. FIG. 16 is a block diagram showing an example of the configuration of a medical image processing apparatus according to the third embodiment.

Below, an embodiment of the medical imaging diagnostic device will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a medical image diagnostic device 1 according to an embodiment, and a blood information acquisition device 2 and an injector 3 connected to the medical image diagnostic device 1. The medical image diagnostic device 1 may include at least one of the blood information acquisition device 2 and the injector 3. In addition, a system including the medical image diagnostic device 1 and at least one of the blood information acquisition device 2 and the injector 3 may be realized as a medical image diagnostic system.

The medical image diagnostic device 1 collects medical images by performing medical imaging on a subject using various imaging principles. The medical image diagnostic device 1 is also a device capable of performing contrast examinations using medical imaging. For example, the medical image diagnostic device 1 is an X-ray computed tomography device (X-ray CT device), a magnetic resonance imaging device, an ultrasound diagnostic device, and an X-ray diagnostic device. Note that the medical image diagnostic device 1 is not limited to these devices as long as it is a device capable of performing contrast examinations using medical imaging.

The blood information acquisition device 2 acquires blood information regarding changes in the amount of red blood cells (hemoglobin amount) contained in blood flowing through blood vessels in a region of the subject. The blood vessels in the region of the subject are, for example, the common carotid artery, radial artery, femoral artery, popliteal artery, posterior tibial artery, or dorsalis pedis artery. All of these blood vessels are arteries near the body surface. The region of the body surface that may contain these blood vessels may be referred to as the first region and the monitoring position. Changes in the hemoglobin amount occur, for example, when saline or contrast agent flows through the blood vessels, thinning the blood in the vessels.

The blood information acquisition device 2 is, for example, an optical sensor and an optical imaging device. When the blood information acquisition device 2 is an optical sensor, the optical sensor is placed in contact with the body surface at a position where blood vessels are present in the subject's part, or away from the body surface. The optical sensor measures the intensity of light of a specific wavelength (e.g., light of a green wavelength) reflected by red blood cells in the blood vessels. The blood information acquired using the optical sensor is sensor information indicating the value (absolute value or relative value) of the hemoglobin amount corresponding to the intensity of light of a specific wavelength.

When the blood information acquisition device 2 is an optical imaging device, the optical imaging device is arranged so that the imaging range is an area including the position of blood vessels in the subject's part. The optical imaging device images the subject's body surface included in the imaging range. The blood information acquired using the optical imaging device is a video of the subject's body surface or images continuously captured. The video or images acquired by the optical imaging device are, for example, analyzed by the medical image diagnostic device 1, and the pixel values are converted into hemoglobin amount values (absolute values or relative values). The video or images acquired by the optical imaging device may be called monitoring images. In the following description, the hemoglobin amount value is expressed as a relative value with the normal state being 100. The normal state is a state in which only blood flows through the blood vessels.

The blood information acquisition device 2 may include, for example, an optical imaging device and an analysis device. In this case, the blood information acquisition device 2 converts the video or images acquired by the optical imaging device into a hemoglobin amount value by image analysis using the analysis device. Alternatively, the optical imaging device may include the analysis device (analysis unit).

The blood information acquisition device 2 may also acquire multiple pieces of blood information corresponding to multiple parts of the subject. When acquiring multiple pieces of blood information, one blood information acquisition device 2 may be prepared, or two or more blood information acquisition devices 2 may be prepared.

The injector 3 injects the contrast agent into the subject according to the injection start timing (injection timing), injection amount, and injection speed set by the medical image diagnostic device 1. When using multiple types of contrast agents, when using contrast agents of multiple concentrations, or when injecting saline in addition to the contrast agent, the injector 3 may have multiple syringes each containing different liquids such as a contrast agent and saline. The injector 3 having multiple syringes operates, for example, to automatically select a syringe in response to an instruction from the medical image diagnostic device 1 and inject the liquid (such as a contrast agent or saline) contained in the selected syringe into the subject.

In the following, for the sake of specific explanation, the medical image diagnostic apparatus according to the first embodiment is an X-ray CT apparatus, and the medical image diagnostic apparatus according to the second embodiment is a magnetic resonance imaging apparatus. In addition, in the third embodiment, the operation using only the medical information processing apparatus included in the medical image diagnostic apparatus 1 will be described. Furthermore, the blood information acquisition apparatus according to each embodiment is an optical imaging apparatus.

First Embodiment
Fig. 2 is a block diagram showing an example of the configuration of the X-ray CT scanner 1A according to the first embodiment. Note that, for convenience of explanation, a plurality of gantry devices 10 are depicted in Fig. 2, but typically, the X-ray CT scanner 1A includes only one gantry device 10.

The X-ray CT device 1A in FIG. 2 has a gantry device 10, a bed device 30, and a console device (medical information processing device) 50. The gantry device 10 is a scanning device (imaging device) configured to perform X-ray computed tomography (X-ray CT imaging) of a subject P. The bed device 30 is a transport device for placing the subject P to be subjected to X-ray CT imaging and positioning the subject P. The medical information processing device 50 is a computer that controls the gantry device 10. The gantry device 10, the bed device 30, and the medical information processing device 50 are connected to each other by wire or wirelessly so that they can communicate with each other. The X-ray CT device 1A is also connected to an optical imaging device 2A and an injector 3.

Of the various components of the X-ray CT apparatus 1A, for example, the gantry device 10 and the bed device 30 are installed in a CT examination room, and the medical information processing device 50 is installed in a control room adjacent to the CT examination room. Note that the medical information processing device 50 does not necessarily have to be installed in the control room. For example, the medical information processing device 50 may be installed in the same room as the gantry device 10 and the bed device 30.

The gantry device 10 includes an X-ray tube 11, an X-ray detector 12, a rotating frame 13, an X-ray high voltage device 14, a control device 15, a wedge filter 16, a collimator 17, and a data acquisition circuit (DAS: Data Acquisition System) 18.

The X-ray tube 11 generates X-rays. Specifically, the X-ray tube 11 includes a cathode that generates thermoelectrons, an anode that receives thermoelectrons flying from the cathode and generates X-rays, and a vacuum tube that holds the cathode and anode. The X-ray tube 11 is connected to the X-ray high voltage device 14 via a high-voltage cable. A filament current is supplied to the cathode by the X-ray high voltage device 14. Thermoelectrons are generated from the cathode by the supply of the filament current. A tube voltage is applied between the cathode and the anode by the X-ray high voltage device 14. The application of the tube voltage causes thermoelectrons to fly from the cathode to the anode and collide with the anode, generating X-rays. The generated X-rays are irradiated onto the subject P. A tube current flows as the thermoelectrons fly from the cathode to the anode.

The X-ray detector 12 detects the X-rays generated from the X-ray tube 11 and passing through the subject P, and outputs an electrical signal corresponding to the detected X-ray dose to the DAS 18. The X-ray detector 12 has a structure in which multiple X-ray detection element rows, each of which has multiple X-ray detection elements arranged in the channel direction, are arranged in the slice direction (row direction). The X-ray detector 12 is, for example, an indirect conversion type detector having a grid, a scintillator array, and an optical sensor array. The scintillator array has multiple scintillators. The scintillator outputs a light amount corresponding to the amount of incident X-rays. The grid is arranged on the X-ray incidence surface side of the scintillator array, and has an X-ray shielding plate that absorbs scattered X-rays. The grid is sometimes called a collimator (one-dimensional collimator or two-dimensional collimator). The optical sensor array converts the light from the scintillator into an electrical signal corresponding to the amount of light. For example, a photodiode is used as the optical sensor.

The rotating frame 13 is an annular frame that supports the X-ray tube 11 and the X-ray detector 12 so that they can rotate around the rotation axis Z. Specifically, the rotating frame 13 supports the X-ray tube 11 and the X-ray detector 12 facing each other. The rotating frame 13 is supported by a fixed frame (not shown) so that they can rotate around the rotation axis Z. The control device 15 rotates the rotating frame 13 around the rotation axis Z, thereby rotating the X-ray tube 11 and the X-ray detector 12 around the rotation axis Z. An image field of view (FOV: Field Of View) is set in an opening 19 of the rotating frame 13.

In this embodiment, the rotation axis of the rotating frame 13 in the non-tilted state or the longitudinal direction of the tabletop 33 of the bed device 30 is defined as the Z-axis direction, the direction perpendicular to the Z-axis direction and horizontal to the floor surface is defined as the X-axis direction, and the direction perpendicular to the Z-axis direction and perpendicular to the floor surface is defined as the Y-axis direction.

The X-ray high voltage device 14 has a high voltage generator and an X-ray control device. The high voltage generator has electrical circuits such as a transformer and a rectifier, and generates a high voltage to be applied to the X-ray tube 11 and a filament current to be supplied to the X-ray tube 11. The X-ray control device controls the high voltage to be applied to the X-ray tube 11 and the filament current to be supplied to the X-ray tube 11. The high voltage generator may be of a transformer type or an inverter type. The X-ray high voltage device 14 may be provided on the rotating frame 13 in the gantry device 10, or on a fixed frame (not shown) in the gantry device 10.

The wedge filter 16 adjusts the dose of X-rays irradiated to the subject P. Specifically, the wedge filter 16 attenuates the X-rays so that the dose of X-rays irradiated from the X-ray tube 11 to the subject P has a predetermined distribution. For example, the wedge filter 16 is a metal filter formed by processing aluminum metal. The wedge filter 16 is processed to have a predetermined target angle and a predetermined thickness. The wedge filter 16 is also called a bow-tie filter.

The collimator 17 limits the irradiation range of the X-rays that have passed through the wedge filter 16. The collimator 17 slidably supports multiple lead plates that block X-rays, and adjusts the shape of the slits formed by the multiple lead plates. The collimator 17 is also called an X-ray aperture.

The DAS 18 reads out an electrical signal corresponding to the X-ray dose detected by the X-ray detector 12 from the X-ray detector 12, amplifies the read electrical signal, and integrates the electrical signal over a view period to collect projection data having a digital value corresponding to the X-ray dose over the view period. The DAS 18 is realized, for example, by an ASIC equipped with a circuit element capable of generating projection data. The projection data generated by the DAS 18 is transmitted by optical communication from a transmitter having a light-emitting diode (LED) provided on the rotating frame 13 to a receiver having a light-emitting diode (LED) provided on a non-rotating part (e.g., a fixed frame) of the gantry 10, and is transmitted from the receiver to the medical information processing device 50. Note that the method of transmitting the projection data from the rotating frame 13 to the non-rotating part of the gantry 10 is not limited to the optical communication described above, and any method of non-contact data transmission may be used.

The bed device 30 includes a base 31 and a tabletop 33. The base 31 is installed on the floor surface. The base 31 is a structure that supports the support frame so that it can move in a direction perpendicular to the floor surface (Y-axis direction). The support frame is a frame provided on the upper part of the base 31. The support frame supports the tabletop 33 so that it can slide along the central axis Z. The tabletop 33 is a flexible plate-like structure on which the subject P is placed. The bed driving device is housed in the bed device 30. The bed driving device is a motor or actuator that generates power to move the tabletop 33 on which the subject P is placed. The bed driving device operates under the control of the control device 15 and the medical information processing device 50, etc.

The control device 15 controls the X-ray high voltage device 14, the DAS 18, and the bed device 30 to perform X-ray CT imaging according to imaging control by the processing circuit 51 (described later) of the medical information processing device 50. The control device 15 has a processing circuit having a CPU (Central Processing Unit) and the like, and a driving device such as a motor and an actuator. The processing circuit of the control device 15 has a processor such as a CPU and a memory such as a ROM and a RAM as hardware resources. The control device 15 controls the gantry device 10 and the bed device 30 according to an operation signal from an input interface 54 (described later) provided in the medical information processing device 50, for example. The input interface 54 may be provided in the gantry device 10 and the bed device 30, etc. For example, the control device 15 controls the rotation of the rotating frame 13, the tilt of the gantry device 10, and the operation of the top plate 33 and the bed device 30. The processor realizes the above control by reading and implementing a program stored in the memory.

The medical information processing device 50 has a processing circuit 51, a memory 52, a display 53, an input interface 54, and a communication interface 55. Data communication between the processing circuit 51, the memory 52, the display 53, the input interface 54, and the communication interface 55 is performed via a bus (BUS). Note that the medical information processing device 50 is described as being separate from the gantry device 10, but the gantry device 10 may include the medical information processing device 50, or the gantry device 10 may include some of the components of the medical information processing device 50.

Below, we will first explain the memory 52, display 53, input interface 54, and communication interface 55, and then explain the processing circuit 51.

The memory 52 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. The memory 52 stores, for example, imaging data and reconstructed image data. In addition to an HDD or SSD, the memory 52 may be a drive device that reads and writes various information between a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a flash memory, or a semiconductor memory element such as a RAM (Random Access Memory). The storage area of the memory 52 may be in the X-ray CT device 1A or in an external storage device connected via a network. For example, the memory 52 stores data of CT images and display images. The memory 52 also stores a control program according to this embodiment.

The display 53 displays various information. For example, the display 53 outputs (displays) medical images generated by the processing circuit 51, a GUI (Graphical User Interface) for receiving various operations from the operator, and the like. For example, as the display 53, for example, a liquid crystal display (LCD), a cathode ray tube (CRT) display, an organic electroluminescence display (OELD), a plasma display, or any other display can be used as appropriate. The display 53 may also be provided on the pedestal device 10. The display 53 may also be a desktop type, or may be configured as a tablet terminal capable of wireless communication with the medical information processing device 50 main body.

The input interface 54 accepts various input operations from the operator, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuit 51. For example, the input interface 54 accepts from the operator the acquisition conditions (which may be called imaging conditions or scan conditions) for acquiring imaging data, the reconstruction conditions for reconstructing a CT image, and the image processing conditions for generating a post-processed image from a CT image.

As the input interface 54, for example, a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display can be used as appropriate.

In this embodiment, the input interface 54 is not limited to having physical operation parts such as a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display. For example, an example of the input interface 54 includes an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs this electrical signal to the processing circuit 51. The input interface 54 may be provided in the gantry device 10. The input interface 54 may also be configured with a tablet terminal capable of wireless communication with the medical information processing device 50 main body.

The communication interface 55 is a circuit for communicating with an external device by wired or wireless communication, or both. In this embodiment, the external device is the optical imaging device 2A and the injector 3, but is not limited to this. The external device may be, for example, a modality, an image processing device, a server included in a system such as a radiological information system (RIS), a hospital information system (HIS), or a picture archiving and communication system (PACS), or another workstation.

The processing circuitry 51 controls the operation of the entire X-ray CT device 1A in response to electrical signals of input operations output from the input interface 54. For example, the processing circuitry 51 has, as hardware resources, processors such as a CPU, MPU (Micro Processing Unit), and GPU (Graphics Processing Unit), and memories such as ROM and RAM.

Specifically, the processing circuit 51 has a system control function 511, an acquisition function 512, an analysis function 513, a setting function 514, a judgment function 515, and a display control function 516. The processing circuit 51 executes the system control function 511, the acquisition function 512, the analysis function 513, the setting function 514, the judgment function 515, and the display control function 516 by a processor that executes a program expanded in memory. Note that each function (system control function 511, acquisition function 512, analysis function 513, setting function 514, judgment function 515, and display control function 516) is not limited to being realized by a single processing circuit. A processing circuit may be configured by combining multiple independent processors, and each processor may execute a program to realize each function. In addition, although not shown, the processing circuit 51 has an imaging control function, a reconstruction processing function, and an image processing function.

The system control function 511 is a function that controls the X-ray CT device 1A based on the input operation received from the operator via the input interface 54. Specifically, the system control function 511 causes the processing circuit 51 to read out a control program stored in the memory 52, expand it on the memory in the processing circuit 51, and control each part of the X-ray CT device 1A according to the expanded control program. For example, the processing circuit 51 controls imaging and each function of the processing circuit 51 based on the input operation received from the operator via the input interface 54. For example, the system control function 511 also obtains a two-dimensional positioning image of the subject P for determining the scan range, imaging conditions, etc. The positioning image is also called a scano image (projection image) or a scout image. The system control function 511 is an example of an imaging unit.

The acquisition function 512 is a function for acquiring data related to the contrast examination. Specifically, the acquisition function 512 causes the processing circuit 51 to acquire vascular information related to changes in the amount of hemoglobin contained in blood in blood vessels at the subject's site. More specifically, the processing circuit 51 acquires a monitoring image as blood information from the optical imaging device 2A. The processing circuit 51 may also acquire sensor information as blood information from an optical sensor. The processing circuit 51 may also acquire a hemoglobin-time density curve (h-TDC) that associates the amount of hemoglobin stored in the memory 52 with time. The acquisition function 512 is an example of an acquisition unit.

The analysis function 513 is a function that creates an h-TDC by analyzing blood information. For example, if the blood information is a monitoring image, the analysis function 513 causes the processing circuit 51 to create an h-TDC based on the monitoring image. Specifically, the processing circuit 51 calculates the hemoglobin amount value from the pixel values of the entire monitoring image or a region of interest in the monitoring image, and creates an h-TDC by expressing the hemoglobin amount value in a time series.

In addition, when the blood information is sensor information, the processing circuit 51 creates an h-TDC based on the sensor information. Specifically, the processing circuit 51 creates an h-TDC by, for example, expressing the value of the hemoglobin amount, which is the sensor information, in a time series.

When creating an h-TDC, if there is a fluctuation in value due to the pulse, the processing circuit 51 may use the value as is without processing the fluctuation, or may use the median or average value of an amplitude that rises and falls due to the pulse. The analysis function 513 is an example of an analysis unit.

The setting function 514 is a function for setting imaging conditions for a contrast examination. Specifically, the setting function 514 causes the processing circuit 51 to set imaging conditions for contrast imaging of a second region of the subject based on blood information. More specifically, the processing circuit 51 sets imaging conditions based on h-TDC analyzed from blood information. The imaging conditions include, for example, the start time of the main scan in contrast imaging. The second region is, for example, a region for which a scan range or a region of interest (ROI) in contrast imaging is specified. Therefore, the second region may be the same as the first region. Note that the setting function 514 is an example of a setting unit.

Furthermore, the processing circuit 51 may use the setting function 514 to set a scan plan and monitor conditions related to the optical imaging device 2A. The scan plan may be, for example, a scan plan using an h-TDC, a scan plan for bolus tracking using the optical imaging device 2A, and a scan plan using multiple h-TDCs. The monitoring conditions related to the optical imaging device 2A may be, for example, a monitoring condition for a test injection using saline and a monitoring condition for bolus tracking using the optical imaging device 2A.

The judgment function 515 is a function that makes various judgments regarding the operation of the X-ray CT device 1A related to contrast examination. Specifically, the judgment function 515 causes the processing circuit 51 to judge whether or not to perform a test injection using saline. The processing circuit 51 may also judge whether or not the scan conditions for performing the main scan are satisfied in bolus tracking using the optical imaging device 2A. The judgment function 515 is an example of a judgment unit.

The display control function 516 is a function that controls the display 53 to display information on the process or results of each function or process of the processing circuit 51. Specifically, the display control function 516 causes the processing circuit 51 to display at least one of the following, or at least two or more of the following side by side: a monitoring image from the optical imaging device 2A, an image in the examination room, monitoring information, h-TDC, a positioning image, a scan image (CT image), and scan information.

In the imaging control function, the processing circuit 51 controls the X-ray high voltage device 14, the control device 15, and the DAS 18 to perform X-ray CT imaging. The processing circuit 51 controls the X-ray high voltage device 14, the control device 15, and the DAS 18 according to user instructions via the input interface 54 or automatically set imaging conditions (X-ray CT imaging parameters).

In the reconstruction processing function, the processing circuitry 51 generates a CT image based on the projection data output from the DAS 18. Specifically, the processing circuitry 51 performs preprocessing such as logarithmic conversion processing, offset correction processing, inter-channel sensitivity correction processing, and beam hardening correction on the projection data output from the DAS 18. The processing circuitry 51 then performs reconstruction processing using a filtered backprojection method, an iterative reconstruction method, or the like on the preprocessed projection data to generate a CT image.

In the image processing function, the processing circuitry 51 converts the CT images generated by the reconstruction processing function into cross-sectional images or three-dimensional images of any cross section based on input operations received from the operator via the input interface 54.

The processing circuitry 51 is not limited to being included in the medical information processing device 50, but may also be included in an integrated server that collectively processes data acquired by multiple medical image diagnostic devices.

The medical information processing device 50 has been described as a single device that executes multiple functions. However, the multiple functions may be executed individually by multiple devices. In other words, the multiple devices may have each function of the processing circuitry 51 distributed individually.

The configuration of the X-ray CT scanner 1A according to the first embodiment has been described above. Below, a first example of the X-ray CT scanner 1A according to the first embodiment will be described. In the first example, a scan plan using an h-TDC will be described.

(First embodiment)
FIG. 3 is a flowchart showing a first example of the X-ray CT apparatus 1A according to the first embodiment. First, the X-ray CT apparatus 1A acquires subject information (patient information) on the subject to be examined from an examination reservation system or the like via the communication interface 55. The subject information includes, for example, a patient ID, a patient name, a date of birth, an age, a weight, a sex, and an examination site. The subject information may also include a scan plan indicating an examination plan. In the first example, the subject information includes a scan plan using h-TDC. In the first example, the examination site is described as being the head. The examination site may also be called an imaging site because it is a site where imaging is performed.

(Step ST101)
After acquiring the subject information, the processing circuitry 51 sets a scan plan using h-TDC by the setting function 514. The scan plan using h-TDC has two patterns, for example, whether or not a test injection using saline is performed. Regarding whether or not a test injection is performed, for example, information on whether or not to perform the test injection may be included in the scan plan, or the user may instruct whether or not to perform the test injection. In the first embodiment, it is assumed that information on whether or not to perform the test injection is included in the scan plan.

(Step ST102)
After setting the scan plan, the processing circuit 51 determines whether or not to perform a test injection using saline by the determination function 515. If the scan plan includes information indicating that a test injection is to be performed, the processing circuit 51 determines that the test injection is to be performed, and if not, determines that the test injection is not to be performed. If it is determined that the test injection is to be performed, the process proceeds to step ST103. If it is determined that the test injection is not to be performed, the process proceeds to step ST108.

(Step ST103)
After it is determined that a test injection is to be performed, the X-ray CT apparatus 1A notifies the user of the positioning of the optical imaging apparatus 2A. At this time, the user installs the optical imaging apparatus 2A so that the subject's body part is included in the monitoring image. The installation position of the optical imaging apparatus 2A will be described below with reference to FIG. 4.

Fig. 4 is an explanatory diagram illustrating the installation positions of the optical imaging device 2A in the first embodiment. Fig. 4 shows an examination room R, and a gantry device 10 and a bed device installed in the examination room R. A subject P is placed on the top plate 33 of the bed device. Seven installation positions Po1 to Po7 are also illustrated in Fig. 4.

Installation position Po1 indicates a state in which it is installed on the side of the gantry device 10. Installation position Po2 indicates a state in which it is built into the gantry device 10. Installation position Po3 indicates a state in which it is installed on the tabletop 33 together with the fixed part. Installation position Po4 indicates a state in which it is installed on the floor surface of the bed device together with the fixed part. Installation position Po5 indicates a state in which it is installed on the ceiling of the examination room R. Installation position Po6 indicates a state in which it is installed on the wall surface of the examination room R. Installation position Po7 indicates a state in which it is installed on the floor surface of the examination room R together with the fixed part.

When limited to performing a test injection, monitoring imaging, which will be described later, is possible in any of the above installation positions. Furthermore, the installation position is not limited to the position shown in FIG. 4. For example, the optical imaging device 2A may be placed on the tabletop 33 during a test injection. In the first embodiment, the optical imaging device 2A is placed on the tabletop 33. Furthermore, the subject's part is, for example, the right neck where the right common carotid artery can be imaged. Furthermore, this part may be called the first part.

(Step ST104)
After positioning the optical imaging device 2A, the processing circuit 51 sets the monitoring conditions for the test injection by the setting function 514. The monitoring conditions for the test injection include, for example, setting of a region of interest (monitoring region of interest) of a monitoring image acquired by the optical imaging device 2A. The region of interest may be set manually by a user from the monitoring image, or may be automatically set by the X-ray CT device 1A by analyzing the monitoring image. The region of interest set here is used in the calculation of the hemoglobin amount, which will be described later.

(Step ST105)
After the monitoring conditions for the test injection are set, the X-ray CT apparatus 1A starts monitoring imaging by the optical imaging device 2A. The monitoring imaging may be started before or at the same time as the injection of physiological saline, which will be described later. The setup situation around the subject in the test injection will be described below with reference to FIG. 5.

Figure 5 is a schematic diagram illustrating the setup situation around the subject in the first embodiment. In Figure 5, the optical imaging device 2A is placed at an arbitrary position where it can image the right neck of the subject P. When the optical imaging device 2A starts monitoring imaging, the medical information processing device 50 acquires monitoring images at any time via the communication interface 55.

(Step ST106)
During monitoring imaging, the X-ray CT apparatus 1A instructs the injector 3 to inject physiological saline. Specifically, after preparation for monitoring imaging is completed, the user instructs the injector 3 to inject physiological saline at any timing via the input interface 54.

As shown in FIG. 5, first, an indwelling needle attached to a tube connected to the injector 3 is placed in a vein in the right arm of the blood vessel BV1 of the subject P. After the injector 3 has been set up, saline is injected into the subject P in response to an instruction from the X-ray CT device 1A. The optical imaging device 2A is positioned so that the imaging range includes the position of the neck artery in the blood vessel BV2 of the subject P.

(Step ST107)
After physiological saline is injected into the subject P, the processing circuitry 51 creates an h-TDC. Specifically, the processing circuitry 51 acquires monitoring images at any time using the acquisition function 512. The processing circuitry 51 calculates the value of the hemoglobin amount based on the monitoring images using the analysis function 513. Then, in response to an instruction to inject physiological saline, the processing circuitry 51 creates an h-TDC by expressing the value of the hemoglobin amount in a time series. The processing circuitry 51 stores the created h-TDC together with subject information in the memory 52 or the like. The display screen of the X-ray CT apparatus 1A during the test injection in the first embodiment will be described below with reference to FIG. 6.

Figure 6 is a diagram illustrating a display screen 600 during test injection in the first embodiment. The display screen 600 in Figure 6 has a display area divided into four, with the upper left of the display screen 600 being area R1, the upper right being area R2, the lower left being area R3, and the lower right being area R4.

A monitoring image 610 captured by the optical imaging device 2A is displayed in region R1 of the display screen 600. The monitoring image 610 shows the area from the shoulders to the head of the subject P, and a monitoring region of interest ROIm is shown in an arbitrary area including the right common carotid artery in the right neck.

An indoor image 620 is displayed in region R2 of the display screen 600. The indoor image 620 shows the entire body of the subject P in order to grasp the condition of the subject P. Note that the optical imaging device 2A and the injector 3 are not shown in the indoor image 620.

Monitoring information 630 regarding the test injection is displayed in region R3 of the display screen 600. The monitoring information 630 includes, for example, information on the monitoring location (e.g., "right common carotid artery"), hemoglobin concentration (e.g., "70%)", saline injection rate (e.g., "1.5 mL/s"), and elapsed time (e.g., "16 s").

The hemoglobin concentration displayed in the monitoring information 630 is, for example, a real-time hemoglobin amount value calculated from the monitoring image 610. The elapsed time displayed in the monitoring information 630 is, for example, the time from the start of saline injection to the present.

The h-TDC analysis results 640 are displayed in region R4 of the display screen 600. The analysis results 640 include the h-TDCs created from the start of saline injection to the present. The h-TDC analysis results are explained below with reference to Figure 7.

Figure 7 is a diagram illustrating an example of an analysis result 700 of an h-TDC in the first embodiment. The analysis result 700 in Figure 7 includes an h-TDC 710. The h-TDC 710 is a graph with time [s] on the horizontal axis and hemoglobin amount [%] on the vertical axis. The h-TDC 710 shown in Figure 7 is, for example, a graph at the completion of a test injection.

Specifically, the h-TDC710 is drawn as a graph after physiological saline is injected into the subject P. In addition, the amount of hemoglobin in the h-TDC710 decreases over time, and after the decrease in the amount of hemoglobin reaches a peak, the amount of hemoglobin increases. In other words, this graph has a shape that is approximately the same as a time density curve (TDC), which is a conventional graph that shows time on the horizontal axis and CT value on the vertical axis.

Furthermore, the analysis result 700 shows the time Ts when the saline solution reaches the monitoring position and the time Tp (peak time) when the hemoglobin amount at the monitoring position is at its lowest. The information on the time Ts and the time Tp may be associated with the h-TDC 710.

(Step ST108)
After it is determined in step ST102 that the test injection is not to be performed, the processing circuitry 51 reads out the past h-TDC of the subject P from the memory 52 or the like by the acquisition function 512. Specifically, the processing circuitry 51 reads out the past h-TDC of the subject P based on the subject information. Note that, if the past h-TDC of the subject P does not exist, or if the h-TDC corresponding to the examination site does not exist, the X-ray CT apparatus 1A may suggest to the user that a test injection is to be performed, or may suggest to the user that a different scan plan is to be performed.

(Step ST109)
After creating the h-TDC in step ST107, or after reading out the h-TDC in step ST108, the processing circuitry 51 sets imaging conditions (scan conditions) related to contrast imaging based on the h-TDC by the setting function 514. The scan conditions in the first embodiment include, for example, a scan waiting time which is a waiting time from when a contrast agent is injected into a subject until when a main scan of an examination region is performed.

Prior to setting the scan conditions, the processing circuit 51 calculates the scan standby time. The scan standby time can be expressed, for example, as the h-TDC peak time + adjustment value. The adjustment value depends, for example, on the positional relationship between the monitoring position and the imaging part. In other words, if the monitoring position and the imaging part are close to each other, the adjustment value will be relatively small, and if the monitoring position and the imaging part are far from each other, the adjustment value will be relatively large.

The calculation of the scan waiting time can be performed, for example, using a coefficient calculated based on a predetermined condition, or using a machine learning model. In the method using the coefficient, the processing circuit 51 calculates a coefficient based on a predetermined condition, and calculates the scan waiting time (peak time + adjustment value) by multiplying the h-TDC peak time by the coefficient. The predetermined condition includes, for example, the relationship between the monitoring position and the imaging site (for example, distance, medical condition, presence or absence of a disorder that affects the blood flow speed, such as vascular stenosis), physical characteristics (for example, blood pressure, heart rate, height, weight, age, sex, imaging site), characteristics of the injection fluid (saline and contrast agent) (for example, injection amount, viscosity, concentration, temperature), and injection conditions (for example, pressure, needle thickness).

In the method using the machine learning model, the processing circuitry 51 uses a trained model that is trained by associating a combination of the h-TDC, the information on the monitoring position as the first part, and the information on the imaging part as the second part, with the scan waiting time corresponding to the imaging part. Another example of the training data set may be, for example, a combination in which the input data is the h-TDC and the output data is the TDC, assuming the same monitoring position. The processing circuitry 51 may further correct the scan waiting time calculated using the trained model based on at least one of the above-mentioned predetermined conditions and the subject information.

(Step ST110)
After the scan conditions are set, the X-ray CT apparatus 1A instructs the injector 3 to inject a contrast agent. Specifically, after the scan conditions are set, the user instructs the injector 3 to inject a contrast agent at any timing via the input interface 54.

(Step ST111)
After the contrast medium is injected into the subject P, the processing circuitry 51 executes the main scan at a timing based on the scan standby time by the system control function 511. Specifically, the processing circuitry 51 starts the main scan after the scan standby time has elapsed since the contrast medium was injected into the subject P. The main scan may be started automatically by the processing circuitry 51, for example, or the processing circuitry 51 may count down the time until the main scan to prompt the user to give a signal to start. After the process of step ST111, the flowchart of the first embodiment in FIG. 3 ends. Hereinafter, the display screen of the X-ray CT apparatus 1A during contrast imaging in the first embodiment will be described with reference to FIG. 8.

Figure 8 is a diagram illustrating a display screen 800 during contrast imaging in the first embodiment. The display screen 800 in Figure 8 has a display area divided into four, with the upper left of the display screen 800 being area R1, the upper right being area R2, the lower left being area R3, and the lower right being area R4.

A positioning image 810 is displayed in region R1 of the display screen 800. The positioning image 810 shows a projection image of the head of subject P, and shows a region of interest (ROI) corresponding to the imaging range.

The CT image 820 being captured is displayed in area R2 of the display screen 800. Note that in the example of FIG. 8, since the actual scan has just started, nothing is displayed on the CT image 820.

Scan information 830 relating to contrast imaging is displayed in region R3 of the display screen 800. The scan information 830 includes, for example, the graph monitoring position (e.g., "right common carotid artery"), the imaging position (e.g., "head"), the graph designation time (e.g., "16.8 s"), the contrast agent injection rate (e.g., "1.5 mL/s"), the start time of the main scan (e.g., "20.0 s"), and the elapsed time (e.g., "0 s").

Area R4 of the display screen 800 displays the analysis result 840 of the h-TDC. The analysis result 840 includes an h-TDC that has been created by performing a test injection or that has been read from the memory 52 or the like. The h-TDC in the analysis result 840 is, for example, the same as the h-TDC 710 in FIG. 7. The analysis result 840 also includes an indicator 841 for specifying a time. For example, the user can operate the indicator 841 to freely set the peak time of the h-TDC that contributes to the scan wait time. The analysis result 840 may also include an indicator that indicates the start time of the main scan.

The graph monitoring position displayed in the scan information 830 is, for example, the monitoring position when the analysis result 840 was obtained. The graph designated time displayed in the scan information 830 is, for example, the time indicated by the indicator 841 included in the analysis result 840. The actual scan start time displayed in the scan information 830 is, for example, the time calculated based on the graph monitoring position, the shooting position, and the graph designated time.

In the above, the case where the optical imaging device 2A is placed on the top plate 33 in the test injection has been described. However, in this case, it is necessary to move the optical imaging device 2A away from the top plate 33 since it may interfere with imaging during the main scan. If it is not necessary to move the optical imaging device 2A away during the main scan and imaging at the monitoring position is possible during the main scan, the processing circuit 51 may acquire monitoring images at any time during contrast imaging. This allows the X-ray CT device 1A to record information on the flow of the contrast agent in the blood vessels. In addition, the X-ray CT device 1A can use information on the flow of the contrast agent in the blood to calculate the scan waiting time in another contrast imaging. Another contrast imaging may be performed on the same subject or on a different subject.

To summarize the first embodiment, the X-ray CT device acquires blood information related to changes in the amount of hemoglobin contained in blood in blood vessels in a first region of the subject, sets imaging conditions related to contrast imaging of a second region of the subject based on the blood information, and performs contrast imaging based on the imaging conditions. An optical imaging device is used to acquire the blood information, and a test injection is performed using saline, which places less strain on the subject than a contrast agent.

A first example of the X-ray CT scanner 1A according to the first embodiment has been described above. Below, a second example of the X-ray CT scanner 1A according to the first embodiment will be described. In the second example, a bolus tracking scan plan using the optical imaging device 2A will be described.

Second Example
Bolus tracking using the optical imaging device 2A is a method for monitoring the contrast agent flowing through blood vessels with the optical imaging device 2A, unlike the usual method of monitoring CT values. Therefore, in this specification, when the term "bolus tracking" is simply described, it is taken to mean a method using the optical imaging device 2A.

Figure 9 is a flow chart showing a second example of the X-ray CT scanner 1A in the first embodiment. First, the X-ray CT scanner 1A acquires subject information (patient information) on the subject to be examined from an examination reservation system or the like via the communication interface 55. In the second example, it is assumed that the subject information includes a bolus tracking scan plan using the optical imaging device 2A. Also, in the second example, it is assumed that the examination site (imaging site) is the head and the first part of the subject is the right neck, as in the first example.

(Step ST201)
After acquiring the subject information, the processing circuitry 51 uses the setting function 514 to set a scan plan for bolus tracking using the optical imaging device 2A.

(Step ST202)
After the scan plan is set, the X-ray CT apparatus 1A notifies the user of the positioning of the optical imaging apparatus 2A. In the second embodiment, the optical imaging apparatus 2A is assumed to be built in the gantry apparatus 10, for example, at an installation position Po2 in FIG.

(Step ST203)
After positioning the optical photographing device 2A, the processing circuit 51 sets the monitoring conditions for bolus tracking by the setting function 514. The monitoring conditions for bolus tracking include, for example, setting the region of interest (monitoring region of interest) of the monitoring image acquired by the optical photographing device 2A. The setting of the region of interest is the same as in the first embodiment.

(Step ST204)
After the monitoring conditions for bolus tracking are set, the processing circuitry 51 sets imaging conditions (scan conditions) for contrast imaging using bolus tracking by the setting function 514. The scan conditions in the second embodiment include, for example, the timing to start the main scan (main scan start timing) and a hemoglobin concentration (main scan start concentration) for setting the main scan start timing.

The main scan start concentration is, for example, a threshold value for hemoglobin concentration. The processing circuit 51 sets the main scan start timing based on, for example, the point in time when the hemoglobin concentration exceeds the main scan start concentration. The main scan start timing can be selected, for example, from either immediately after the hemoglobin concentration reaches the main scan start concentration (immediately after reaching), or a predetermined time after the hemoglobin concentration reaches the main scan start concentration. The predetermined time may be specified by the user, or may be calculated by the processing circuit 51 based on the monitoring position and the imaging area.

(Step ST205)
After the scan conditions are set, the X-ray CT apparatus 1A starts monitoring imaging by the optical imaging device 2A. The monitoring imaging may be started before the injection of a contrast agent, which will be described later, or may be started simultaneously with the injection of the contrast agent. The setup situation around the subject in bolus tracking will be described below with reference to FIG. 10.

Figure 10 is a schematic diagram illustrating the setup situation around the subject in the second embodiment. In Figure 10, the optical imaging device 2A is built into the gantry device 10. When the optical imaging device 2A starts monitoring imaging, the medical information processing device 50 acquires monitoring images at any time via the communication interface 55.

(Step ST206)
During monitoring imaging, the X-ray CT apparatus 1A instructs the injector 3 to inject a contrast agent. Specifically, after scan conditions are set and preparation for monitoring imaging is completed, the user instructs the injector 3 to inject a contrast agent at any timing via the input interface 54. Note that the setting of the injector 3 into the subject P is the same as in the first embodiment, and therefore will not be described here.

(Step ST207)
After the contrast agent is injected into the subject P, the processing circuitry 51 creates an h-TDC. Specifically, the processing circuitry 51 acquires monitoring images at any time using the acquisition function 512. The processing circuitry 51 calculates the value of the hemoglobin amount based on the monitoring images using the analysis function 513. Then, in response to an instruction to inject the contrast agent, the processing circuitry 51 creates an h-TDC by expressing the value of the hemoglobin amount in a time series. The processing circuitry 51 stores the created h-TDC together with subject information in the memory 52 or the like. Hereinafter, the display screen of the X-ray CT apparatus 1A during contrast imaging using bolus tracking in the second embodiment will be described with reference to FIG. 11.

Figure 11 is a diagram illustrating a display screen 1100 during contrast imaging using bolus tracking in the second embodiment. The display screen 1100 in Figure 11 has a display area divided into four areas, with the upper left of the display screen 1100 being area R1, the upper right being area R2, the lower left being area R3, and the lower right being area R4.

A positioning image 1110 is displayed in region R1 of the display screen 1100. The positioning image 1110 shows a projection image of the head of subject P, and displays a region of interest ROI corresponding to the imaging range. Furthermore, the positioning image 1110 shows a monitoring region of interest ROIm corresponding to the monitoring position (near the right common carotid artery in FIG. 11).

The CT image 1120 being captured is displayed in area R2 of the display screen 1100. Note that in the example of FIG. 11, the actual scan has not yet started, so nothing is displayed on the CT image 1120.

Scan information 1130 relating to contrast imaging using bolus tracking is displayed in region R3 of display screen 1100. Scan information 1130 includes, for example, information on the start timing of the main scan (e.g., "immediately after arrival"), monitoring position (e.g., "right common carotid artery"), start concentration of the main scan (e.g., "70%)", contrast injection rate (e.g., 1.5 mL/s), and elapsed time (e.g., "12 s").

Area R4 on the display screen 1100 displays the h-TDC analysis results 1140. The analysis results 1140 include the h-TDCs created from the start of contrast agent injection to the present. The analysis results 1140 also include an indicator 1141 indicating a threshold value that is the main scan start concentration. For example, the user can operate the indicator 1141 to freely set the main scan start concentration that contributes to the main scan start timing. The analysis results 1140 may also include an indicator indicating the main scan start time.

(Step ST208)
During the creation of the h-TDC, the processing circuitry 51 uses the judgment function 515 to judge whether or not the current hemoglobin concentration value satisfies the scan condition. Specifically, the processing circuitry 51 judges whether or not the current hemoglobin concentration value (hemoglobin amount value) is equal to or greater than the main scan start concentration (threshold value) included in the scan condition. If the hemoglobin amount value is equal to or greater than the threshold value, the processing circuitry 51 judges that the scan condition is satisfied, and if not, judges that the scan condition is not satisfied. If it is judged that the scan condition is satisfied, the process proceeds to step ST209. If it is judged that the scan condition is not satisfied, the process repeats step ST208.

(Step ST209)
After it is determined that the scan conditions are satisfied, the processing circuitry 51 starts the main scan at the main scan start timing by the system control function 511. Specifically, if the main scan start timing is "immediately after arrival", the processing circuitry 51 starts the main scan at the time when the scan conditions are satisfied. The main scan may be started automatically by the processing circuitry 51, for example, or the processing circuitry 51 may count down the time until the main scan to prompt the user to give a signal to start. After the process of step ST209, the flowchart of the second embodiment in FIG. 9 ends.

In the second embodiment, the X-ray CT scanner 1A may store information on the flow of the contrast agent in the blood, as in the first embodiment. In addition, the X-ray CT scanner 1A may use the information on the flow of the contrast agent in the blood to calculate the scan waiting time in another contrast imaging.

To summarize the second embodiment, the X-ray CT device acquires blood information related to changes in the amount of hemoglobin contained in blood in blood vessels in a first region of a subject, sets imaging conditions related to contrast imaging of a second region of the subject based on the blood information, and performs contrast imaging based on the imaging conditions. An optical imaging device that is not exposed to radiation is used to acquire blood information by bolus tracking.

The second example of the X-ray CT scanner 1A according to the first embodiment has been described above. Below, a third example of the X-ray CT scanner 1A according to the first embodiment will be described.

(Third Example)
In the first and second examples, a scan plan using one h-TDC is described. In the third example, a scan plan using multiple h-TDCs is described. In the third example, a case where one optical imaging device is used to obtain multiple blood information is described, but multiple optical imaging devices may be used.

Figure 12 is a flowchart showing a third example of the X-ray CT apparatus according to the first embodiment. First, the X-ray CT apparatus 1A acquires subject information (patient information) related to the subject to be examined from an examination reservation system or the like via the communication interface 55. In the third example, it is assumed that the subject information includes a scan plan using multiple h-TDCs. In addition, in the third example, it is assumed that the examination site (imaging site) is the lower limb (thigh, lower leg, and foot).

In the third embodiment, the processing circuitry 51 acquires multiple pieces of blood information corresponding to multiple parts of the subject using the acquisition function 512. The processing circuitry 51 creates multiple h-TDCs by analyzing each of the multiple pieces of blood information using the analysis function 513. The processing circuitry 51 sets imaging conditions for contrast imaging for the imaging parts based on the multiple h-TDCs using the setting function 514. Note that when there are two parts, the two parts may be referred to as the first part and the third part, respectively. Also, the second part is the imaging part.

(Step ST301)
After acquiring the subject information, the processing circuitry 51 sets a scan plan using multiple h-TDCs by the setting function 514. The scan plan using multiple h-TDCs has two patterns, for example, whether or not to perform a test injection using saline. Regarding whether or not to perform a test injection, for example, information on whether or not to perform the test injection may be included in the scan plan, or the user may instruct whether or not to perform the test injection. In the third embodiment, it is assumed that information on whether or not to perform the test injection is included in the scan plan.

(Step ST302)
After setting the scan plan, the processing circuit 51 determines whether or not to perform a test injection using saline by the determination function 515. If the scan plan includes information indicating that a test injection is to be performed, the processing circuit 51 determines that the test injection is to be performed, and if not, determines that the test injection is not to be performed. If it is determined that the test injection is to be performed, the process proceeds to step ST303. If it is determined that the test injection is not to be performed, the process proceeds to step ST308.

(Step ST303)
After it is determined that the test injection is to be performed, the X-ray CT apparatus 1A notifies the user of the positioning of the optical imaging device 2A. At this time, the user installs the optical imaging device 2A so that a plurality of parts of the subject are included in the monitoring image. For example, in the third embodiment, the optical imaging device 2A is built into the gantry device 10, as shown in the installation position Po2 in FIG.

(Step ST304)
After positioning the optical imaging device 2A, the processing circuit 51 sets the monitoring conditions for the test injection by the setting function 514. The monitoring conditions for the test injection include, for example, setting of a region of interest (monitoring region of interest) of a monitoring image acquired by the optical imaging device 2A. The region of interest may be set manually by a user from the monitoring image, or may be automatically set by the X-ray CT device 1A by analyzing the monitoring image. In the third embodiment, a plurality of monitoring regions of interest are set. The region of interest set here is used in the calculation of the hemoglobin amount described later.

The multiple monitoring regions of interest may be set by one monitoring image, or may be set by multiple monitoring images acquired from each of the multiple optical imaging devices 2A. Specifically, if the imaging region is the lower leg and the monitoring position is the upper part of the thigh and the foot, the processing circuit 51 may set the upper part of the thigh and the foot as monitoring regions of interest from one monitoring image including the entire lower leg, or may set monitoring regions of interest from two monitoring images including the upper part of the thigh and the foot, respectively.

(Step ST305)
After the monitoring conditions for the test injection are set, the X-ray CT apparatus 1A starts monitoring imaging by the optical imaging device 2A. The monitoring imaging may start before or at the same time as the injection of physiological saline, which will be described later. The setup situation around the subject in the test injection will be described below with reference to FIG. 13.

Figure 13 is a schematic diagram illustrating the setup situation around the subject in the third embodiment. In Figure 13, the optical imaging device 2A is built into the gantry device 10 (not shown). When the optical imaging device 2A starts monitoring imaging, the medical information processing device 50 acquires monitoring images at any time via the communication interface 55.

For ease of explanation, the monitoring image in FIG. 13 shows the area through which the lower limb arteries pass with dashed lines. The monitoring image in FIG. 13 includes the lower limbs of subject P, with a first monitoring region of interest ROIm1 set in the upper part of the thigh and a monitoring region of interest ROIm2 set in the foot. Both the first monitoring region of interest ROIm1 and the second monitoring region of interest ROIm2 are set in ranges that include the lower limb arteries. Note that some or all of the lower limb arteries may not be shown in the actual monitoring image.

(Step ST306)
During monitoring imaging, the X-ray CT apparatus 1A instructs the injector 3 to inject physiological saline. Specifically, after preparation for monitoring imaging is completed, the user instructs the injector 3 to inject physiological saline at any timing via the input interface 54. Note that the setting of the injector 3 into the subject P is the same as in the first embodiment, and therefore will not be described here.

(Step ST307)
After physiological saline is injected into the subject P, the processing circuitry 51 creates a plurality of h-TDCs. Specifically, the processing circuitry 51 acquires monitoring images at any time using the acquisition function 512. The processing circuitry 51 calculates the hemoglobin amount values at different monitoring positions based on the monitoring images using the analysis function 513. Then, in response to an instruction to inject physiological saline, the processing circuitry 51 creates a plurality of h-TDCs for the different monitoring positions. The processing circuitry 51 stores the created plurality of h-TDCs together with subject information in the memory 52 or the like. Hereinafter, the analysis results of the plurality of h-TDCs will be described with reference to FIG. 14.

Figure 14 is a diagram illustrating the analysis results of multiple h-TDCs in the third embodiment. The analysis result 1400 in Figure 14 includes a first h-TDC 1410 and a second h-TDC 1420. The first h-TDC 1410 and the second h-TDC 1420 are graphs with time [s] on the horizontal axis and hemoglobin amount [%] on the vertical axis. The first h-TDC 1410 and the second h-TDC 1420 shown in Figure 14 are graphs at the completion of test injection, for example.

Furthermore, the analysis result 1400 shows the time Ts1 when the saline solution reaches the first monitoring position (e.g., the upper part of the thigh) and the time Tp1 (first peak time) when the hemoglobin amount at the first monitoring position is the lowest. The analysis result 1400 also shows the time Ts2 when the saline solution reaches the second monitoring position (e.g., the foot) and the time Tp2 (second peak time) when the hemoglobin amount at the second monitoring position is the lowest. The information on the times Ts1 and Tp1 may be associated with the h-TDC 1410, and the information on the times Ts2 and Tp2 may be associated with the h-TDC 1420.

(Step ST308)
After it is determined in step ST302 that the test injection is not to be performed, the processing circuitry 51 reads out a plurality of past h-TDCs of the subject P from the memory 52 or the like by the acquisition function 512. Specifically, the processing circuitry 51 reads out a plurality of past h-TDCs of the subject P based on the subject information. Note that, when a plurality of past h-TDCs of the subject P do not exist, or a plurality of h-TDCs corresponding to the examination region do not exist, the X-ray CT apparatus 1A may suggest to the user that a test injection is to be performed, or may suggest to the user that a different scan plan is to be performed.

(Step ST309)
After creating a plurality of h-TDCs in step ST307, or after reading out a plurality of h-TDCs in step ST308, the processing circuitry 51 sets imaging conditions (scan conditions) related to contrast imaging based on the plurality of h-TDCs by the setting function 514. The scan conditions in the third embodiment include, for example, a plurality of scan waiting times.

Prior to setting the scan conditions, the processing circuitry 51 calculates multiple scan wait times. In the third embodiment, since it is assumed that a wide area of the imaging region is to be imaged, the imaging region is divided into several regions and the scan wait time for each is calculated. Specifically, the processing circuitry 51 calculates three scan wait times for the thigh, the lower leg, and the foot. The calculation of each scan wait time is substantially similar to that in the first embodiment, and therefore a description thereof will be omitted. By calculating multiple scan wait times in this manner, the X-ray CT apparatus 1A can prevent overtaking of scans, such as performing a scan even when no contrast agent has flowed.

When performing a helical scan, the processing circuitry 51 may set different scan conditions for each region of the imaging part. The scan conditions here are, for example, the moving speed of the tabletop 33 and the rotation speed of the rotating frame 13. Specifically, when performing a helical scan of the lower limbs, the processing circuitry 51 may set different scan conditions for each of the thighs, lower legs, and feet, for example.

(Step ST310)
After the scan conditions are set, the X-ray CT apparatus 1A instructs the injector 3 to inject a contrast agent. Specifically, after the scan conditions are set, the user instructs the injector 3 to inject a contrast agent at any timing via the input interface 54.

(Step ST311)
After the contrast agent is injected into the subject P, the processing circuitry 51 executes a main scan at a timing based on a plurality of scan standby times by the system control function 511. For example, the main scan may be started automatically by the processing circuitry 51, or the processing circuitry 51 may count down the time until the main scan to prompt the user to give a signal to start. Note that the main scan may be started only by an instruction for the region where imaging is to be started first. After the process of step ST311, the flowchart of the third embodiment in FIG. 12 ends.

In the third embodiment, the X-ray CT scanner 1A may store information on the flow of the contrast agent in the blood, as in the first and second embodiments. In addition, the X-ray CT scanner 1A may use the information on the flow of the contrast agent in the blood to calculate the scan waiting time in another contrast imaging.

In summary of the third embodiment, the X-ray CT device acquires blood information related to changes in the amount of hemoglobin contained in blood in blood vessels in a first region of the subject, sets imaging conditions for contrast imaging of a second region of the subject based on the blood information, and performs contrast imaging based on the imaging conditions. As in the first embodiment, an optical imaging device is used to acquire the blood information, and a test injection is performed using saline, which places less strain on the subject than a contrast agent. Furthermore, in the third embodiment, multiple pieces of blood information are acquired, making it possible to set scan conditions in detail, thereby preventing overtaking of the scan even in a wide imaging region.

The multiple blood information described in the third embodiment may also be used in the bolus tracking described in the second embodiment.

In addition, if the optical imaging device 2A (or blood information acquisition device 2) can acquire information equivalent to a pulse oximeter (e.g., oxygen saturation), the X-ray CT device 1A may be used for breathing (breath holding) control during X-ray CT imaging.

As described above, the medical imaging diagnostic apparatus according to the first embodiment acquires blood information regarding changes in the amount of hemoglobin contained in blood in blood vessels in a first region of a subject, sets imaging conditions for contrast imaging of a second region of the subject based on the blood information, and performs contrast imaging based on the imaging conditions.

Therefore, the medical imaging diagnostic apparatus according to the first embodiment can eliminate the need for test injections using contrast agents and bolus tracking using X-rays, thereby reducing the burden on the subject when performing vascular examinations.

Second Embodiment
In the first embodiment, an X-ray CT apparatus has been described, whereas in the second embodiment, a magnetic resonance imaging apparatus will be described.

Figure 15 is a block diagram showing an example of the configuration of a magnetic resonance imaging apparatus 1B according to the second embodiment. As shown in Figure 15, the magnetic resonance imaging apparatus 1B has a gantry device 10-2, a bed device 30-2, a gradient magnetic field power supply 21, a transmission circuit 23, a reception circuit 25, a bed driving device 27, a sequence control circuit 29, and a console device (medical information processing device) 50-2. The magnetic resonance imaging apparatus 1B is also connected to an optical imaging device 2A and an injector 3.

The gantry 10-2 has a static magnetic field magnet 41 and a gradient magnetic field coil 43. The static magnetic field magnet 41 and the gradient magnetic field coil 43 are housed in the housing of the gantry 10-2. A hollow bore is formed in the housing of the gantry 10-2. A transmitting coil 45 and a receiving coil 47 are arranged in the bore of the gantry 10-2.

The static magnetic field magnet 41 has a hollow, approximately cylindrical shape, and generates a static magnetic field inside the approximately cylinder. For example, a permanent magnet, a superconducting magnet, or a normal conducting magnet is used as the static magnetic field magnet 41. Here, the central axis of the static magnetic field magnet 41 is defined as the Z axis, the axis perpendicular to the Z axis is defined as the Y axis, and the axis horizontally perpendicular to the Z axis is defined as the X axis. The X axis, Y axis, and Z axis form an orthogonal three-dimensional coordinate system.

The gradient coil 43 is a coil unit attached to the inside of the static magnetic field magnet 41 and formed in a hollow, approximately cylindrical shape. The gradient coil 43 generates a gradient magnetic field by receiving a current from the gradient magnetic field power supply 21. More specifically, the gradient coil 43 has three coils corresponding to the X-axis, Y-axis, and Z-axis that are mutually orthogonal. The three coils form a gradient magnetic field whose magnetic field strength changes along each of the X-axis, Y-axis, and Z-axis. The gradient magnetic fields along each of the X-axis, Y-axis, and Z-axis are synthesized to form a slice selection gradient magnetic field Gs, a phase encoding gradient magnetic field Gp, and a frequency encoding gradient magnetic field Gr that are mutually orthogonal in a desired direction. The slice selection gradient magnetic field Gs is used to arbitrarily determine an imaging section (slice). The phase encoding gradient magnetic field Gp is used to change the phase of a magnetic resonance signal (hereinafter referred to as an MR signal) according to a spatial position. The frequency encoding gradient magnetic field Gr is used to change the frequency of the MR signal according to a spatial position. In the following description, the gradient direction of the slice selection gradient magnetic field Gs is the Z axis, the gradient direction of the phase encoding gradient magnetic field Gp is the Y axis, and the gradient direction of the frequency encoding gradient magnetic field Gr is the X axis.

The gradient magnetic field power supply 21 supplies current to the gradient magnetic field coil 43 in accordance with a sequence control signal from the sequence control circuit 29. The gradient magnetic field power supply 21 supplies current to the gradient magnetic field coil 43, causing the gradient magnetic field coil 43 to generate gradient magnetic fields along the X-axis, Y-axis, and Z-axis. The gradient magnetic field is superimposed on the static magnetic field formed by the static magnetic field magnet 41 and applied to the subject P.

The transmission coil 45 is disposed, for example, inside the gradient magnetic field coil 43, and receives a current from the transmission circuit 23 to generate a radio frequency magnetic field pulse (hereinafter referred to as an RF magnetic field pulse).

The transmission circuit 23 supplies a current to the transmission coil 45 in order to apply an RF magnetic field pulse to the subject P via the transmission coil 45 in order to excite the target protons present in the subject P. The RF magnetic field pulse oscillates at a resonance frequency specific to the target protons, exciting the target protons. An MR signal is generated from the excited target protons and is detected by the reception coil 47. The transmission coil 45 is, for example, a whole-body coil (WB coil). The whole-body coil may be used as a transmission/reception coil.

The receiving coil 47 receives MR signals emitted from target protons present in the subject P in response to the action of an RF magnetic field pulse. The receiving coil 47 has multiple receiving coil elements capable of receiving MR signals. The received MR signals are supplied to the receiving circuit 25 via wire or wirelessly. Although not shown in FIG. 15, the receiving coil 47 has multiple receiving channels implemented in parallel. Each receiving channel has a receiving coil element that receives the MR signal and an amplifier that amplifies the MR signal. The MR signal is output for each receiving channel. The total number of receiving channels and the total number of receiving coil elements may be the same, or the total number of receiving channels may be greater or less than the total number of receiving coil elements.

The receiving circuit 25 receives the MR signal generated from the excited target protons via the receiving coil 47. The receiving circuit 25 processes the received MR signal to generate a digital MR signal. The digital MR signal can be expressed in k-space defined by spatial frequency. Therefore, hereinafter, the digital MR signal will be referred to as k-space data. The k-space data is supplied to the medical information processing device 50-2 via a wired or wireless connection.

The above-mentioned transmitting coil 45 and receiving coil 47 are merely examples. Instead of the transmitting coil 45 and receiving coil 47, a transmitting/receiving coil having a transmitting function and a receiving function may be used. Also, the transmitting coil 45, the receiving coil 47, and the transmitting/receiving coil may be combined.

The bed device 30-2 is installed adjacent to the gantry device 10-2. The bed device 30-2 has a tabletop 33-2 and a base 31-2. The subject P is placed on the tabletop 33-2. The base 31-2 supports the tabletop 33-2 so that it can slide along the X-axis, Y-axis, and Z-axis. The base 31-2 houses a bed driving device 27. The bed driving device 27 moves the tabletop 33-2 under the control of a sequence control circuit 29. The bed driving device 27 may include any motor, such as a servo motor or a stepping motor.

The sequence control circuit 29 has, as hardware resources, a processor such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit) and memories such as a ROM (Read Only Memory) or a RAM (Random Access Memory). The sequence control circuit 29 synchronously controls the gradient magnetic field power supply 21, the transmission circuit 23, and the reception circuit 25 based on an imaging protocol determined by the processing circuit 51, etc., performs imaging using magnetic resonance imaging (MR imaging) on the subject P according to a pulse sequence corresponding to the imaging protocol, and collects k-space data on the subject P.

As shown in FIG. 15, the medical information processing device 50-2 is a computer having a processing circuit 51, a memory 52, a display 53, an input interface 54, and a communication interface 55.

The processing circuitry 51 has a processor such as a CPU as a hardware resource. The processing circuitry 51 functions as the core of the magnetic resonance imaging apparatus 1B. For example, the processing circuitry 51 has a system control function 511, an acquisition function 512, an analysis function 513, a setting function 514, a judgment function 515, and a display control function 516 by executing various programs. Although not shown, the processing circuitry 51 has an image reconstruction function and an image processing function by executing various programs.

In the image reconstruction function, the processing circuitry 51 reconstructs an MR image based on the k-space data collected by various scans. There are no particular limitations on the reconstruction method.

In the image processing function, the processing circuitry 51 performs various image processing on the MR image. For example, the processing circuitry 51 performs image processing such as volume rendering, surface rendering, pixel value projection processing, MPR (Multi-Planer Reconstruction) processing, and CPR (Curved MPR) processing.

The system control function 511 is a function that controls the magnetic resonance imaging apparatus 1B based on input operations received from the operator via the input interface 54. Specifically, the system control function 511 causes the processing circuitry 51 to read out a control program stored in the memory 52, expand it on the memory within the processing circuitry 51, and control each part of the magnetic resonance imaging apparatus 1B according to the expanded control program. For example, the processing circuitry 51 controls each function of the processing circuitry 51 based on input operations received from the operator via the input interface 54.

The display control function 516 is a function that controls the display 53 to display information on the process or results of each function or process of the processing circuit 51. Specifically, the display control function 516 causes the processing circuit 51 to display at least one of the following, or at least two or more of the following side by side: a monitoring image from the optical imaging device 2A, an image in the examination room, monitoring information, h-TDC, a positioning image, a scan image (MR image), and scan information.

The processing circuitry 51 is not limited to being included in the medical information processing device 50-2, but may also be included in an integrated server that collectively processes data acquired by multiple medical image diagnostic devices.

The memory 52 is a storage device such as a HDD (Hard Disk Drive), SSD (Solid State Drive), or integrated circuit storage device that stores various information. The memory 52 stores, for example, imaging data and reconstructed image data. In addition to an HDD or SSD, the memory 52 may be a drive device that reads and writes various information between a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a flash memory, or a semiconductor memory element such as a RAM (Random Access Memory). The storage area of the memory 52 may be in the magnetic resonance imaging apparatus 1B or in an external storage device connected via a network. For example, the memory 52 stores data of MR images and display images. The memory 52 also stores a control program according to this embodiment.

The input interface 54 accepts various input operations from the operator, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuit 51. For example, the input interface 54 accepts from the operator the acquisition conditions (which may be called imaging conditions or scan conditions) for acquiring imaging data, the reconstruction conditions for reconstructing MR images, and the image processing conditions for generating post-processed images from MR images.

Note that the acquisition function 512, analysis function 513, setting function 514, judgment function 515, display 53, and communication interface 55 are substantially the same as those in the first embodiment, and therefore will not be described here.

The medical information processing device 50-2 has been described as a single device that executes multiple functions. However, the multiple functions may be executed individually by multiple devices. In other words, the multiple devices may have each function of the processing circuitry 51 distributed individually.

The configuration of the magnetic resonance imaging apparatus 1B according to the second embodiment has been described above. Note that an example of a contrast examination using the magnetic resonance imaging apparatus 1B is basically performed in a procedure similar to that of a contrast examination using an X-ray CT scanner, and therefore a description thereof will be omitted.

As described above, the magnetic resonance imaging apparatus according to the second embodiment acquires blood information regarding changes in the amount of hemoglobin contained in blood in blood vessels in a first region of a subject, sets imaging conditions for contrast imaging of a second region of the subject based on the blood information, and performs contrast imaging based on the imaging conditions.

Therefore, the magnetic resonance imaging apparatus according to the second embodiment can eliminate the need for test injections using a contrast agent, thereby reducing the burden on the subject when performing blood vessel examinations. In addition, the magnetic resonance imaging apparatus according to the second embodiment can reduce the specific absorption rate (SAR) in MRI examinations by performing bolus tracking using an optical imaging device.

Third Embodiment
In the first and second embodiments, a medical image diagnostic apparatus has been described, whereas in the third embodiment, a medical image processing apparatus will be described.

Figure 16 is a block diagram showing an example of the configuration of a medical information processing device 50-3 according to the third embodiment. The medical information processing device 50-3 is a computer having a processing circuit 51, a memory 52, a display 53, an input interface 54, and a communication interface 55. The medical information processing device 50-3 is also connected to the optical imaging device 2A and the injector 3.

The processing circuitry 51 has a processor such as a CPU as a hardware resource. The processing circuitry 51 functions as the core of the medical information processing device 50-3. For example, the processing circuitry 51 has a system control function 511, an acquisition function 512, an analysis function 513, a judgment function 515, and a display control function 516 by executing various programs.

The system control function 511 is a function that controls the medical information processing device 50-3 based on input operations received from the operator via the input interface 54. Specifically, the system control function 511 causes the processing circuitry 51 to read out a control program stored in the memory 52, expand it on the memory within the processing circuitry 51, and control the medical information processing device 50-3 according to the expanded control program. For example, the processing circuitry 51 controls each function of the processing circuitry 51 based on input operations received from the operator via the input interface 54.

The acquisition function 512 is a function for acquiring data related to a blood flow test. The blood flow test here refers to a test that does not use a contrast agent. Specifically, the acquisition function 512 causes the processing circuit 51 to acquire blood information related to changes in the amount of hemoglobin contained in the blood in blood vessels at the subject's site. More specifically, the processing circuit 51 acquires a monitoring image as blood information from the optical imaging device 2A. The processing circuit 51 may also acquire sensor information as blood information from an optical sensor. The acquisition function 512 is an example of an acquisition unit.

The analysis function 513 is a function that creates an h-TDC by analyzing blood information. The details of the analysis function 513 are substantially the same as those in the first embodiment, and therefore will not be described here.

The judgment function 515 is a function that makes various judgments about the analysis results related to the blood flow test. Specifically, the judgment function 515 causes the processing circuit 51 to judge the presence or absence of a disease by comparing different h-TDCs. More specifically, the processing circuit 51 compares, for example, the h-TDC created in the most recent blood flow test with a given h-TDC. The given h-TDC is, for example, a typical h-TDC of a healthy person and an h-TDC of subject P that was created in the past. By such a comparison, the processing circuit 51 can, for example, judge the presence or absence of a possibility of a disease in which the arrival of blood flow is delayed (for example, arterioSclerosis obliterans (ASO) and varicose veins) based on the state of blood flow (for example, delay).

The medical information processing device 50-3 is not limited to comparing different h-TDCs related to a specific part of the subject, but may also compare different h-TDCs related to different parts of the subject. Specifically, the medical information processing device 50-3 can create different h-TDCs related to different parts of the subject by freely arranging one or more optical imaging devices 2A, and therefore, for example, the blood circulation state of the entire body can be understood by comparing these different h-TDCs.

The medical information processing device 50-3 may also use the created h-TDC to evaluate and estimate lung function. For example, the medical information processing device 50-3 may create h-TDCs before and after oxygen is inhaled by the subject, and calculate the oxygen absorption efficiency by comparing the two h-TDCs.

In addition, if the optical imaging device 2A (or the blood information acquisition device 2) can acquire information equivalent to that of a pulse oximeter (e.g., oxygen saturation), the medical information processing device 50-3 may evaluate and estimate lung function using the oxygen saturation as an analysis result.

The medical information processing device 50-3 may also determine the imaging conditions for any medical imaging diagnostic device based on the created h-TDC.

As described above, the medical information processing device according to the third embodiment acquires blood information related to changes in the amount of hemoglobin contained in blood in blood vessels at a site of the subject, analyzes the blood information to generate a time-concentration curve that correlates the amount of hemoglobin with time, and determines the presence or absence of a disease by comparing the generated time-concentration curve with a given time-concentration curve.

The medical information processing device according to the third embodiment can therefore perform blood flow examinations without using contrast agents or X-rays, reducing the burden on the subject when performing examinations related to blood vessels.

According to at least one of the embodiments described above, it is possible to reduce the burden on the subject when performing vascular examinations.

In addition, the term "processor" used in the above explanation refers to circuits such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or an application specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). If the processor is, for example, a CPU, the processor realizes the function by reading and executing a program stored in a memory circuit. On the other hand, if the processor is, for example, an ASIC, instead of storing the program in a memory circuit, the function is directly incorporated as a logic circuit in the circuit of the processor. Note that each processor in this embodiment is not limited to being configured as a single circuit for each processor, but may be configured as a single processor by combining multiple independent circuits to realize the function. Furthermore, multiple components in the figure may be integrated into a single processor to realize the function.

In addition, each function according to the embodiment can be realized by installing a program that executes the above-mentioned processes in a computer such as a workstation and expanding the program in memory. In this case, the program that can cause the computer to execute the above-mentioned methods can also be stored and distributed on a storage medium such as a magnetic disk (such as a hard disk), an optical disk (such as a CD-ROM or DVD), or a semiconductor memory.

Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments can be made without departing from the spirit of the invention. These embodiments and their modifications are within the scope of the invention and its equivalents as set forth in the claims, as well as the scope and spirit of the invention.

With regard to the above embodiment, the following notes are disclosed as one aspect and optional feature of the invention.

(Appendix 1)
an acquisition unit that acquires blood information related to a change in an amount of hemoglobin contained in blood in a blood vessel at a first site of a subject;
a setting unit that sets imaging conditions for contrast imaging of a second region of the subject based on the blood information;
an imaging unit that performs the contrast imaging based on the imaging conditions;
A medical image diagnostic apparatus comprising:

(Appendix 2)
an analysis unit that generates a time-concentration curve that correlates the hemoglobin amount with time by analyzing the blood information;
Further comprising:
The setting unit may set the imaging condition based on the time-density curve.

(Appendix 3)
the blood information is an image obtained by optically photographing the first site,
The analysis unit may generate the time-density curve by analyzing the image.

(Appendix 4)
An optical photographing device for acquiring the image by optically photographing the first portion.
It may further comprise:

(Appendix 5)
the blood information is sensor information indicating a value of the hemoglobin amount obtained by sensing a blood vessel in the first region,
The analysis unit may generate the time-density curve based on the sensor information.

(Appendix 6)
a sensor for acquiring the sensor information by sensing a blood vessel in the first region;
It may further comprise:

(Appendix 7)
a memory for storing the time-density curve and examination information including information of the subject in association with each other;
It may further comprise:

(Appendix 8)
said memory stores a given time-concentration curve;
The acquisition unit acquires the given time-density curve from the memory;
The setting unit may set the imaging condition based on the given time-density curve.

(Appendix 9)
The given time-density curve may be a historical time-density curve of the subject or a typical time-density curve of a healthy individual.

(Appendix 10)
the imaging condition includes a threshold value related to the value of the hemoglobin amount,
a determination unit that determines whether the amount of hemoglobin is equal to or greater than the threshold value after injecting a contrast agent into the blood vessel of the subject;
Further comprising:
The imaging section may perform the contrast imaging based on a time point when the value of the hemoglobin amount becomes equal to or greater than the threshold value.

(Appendix 11)
The setting unit may set the time point at which the amount of hemoglobin becomes equal to or greater than the threshold value as the start time of the contrast imaging.

(Appendix 12)
The setting unit may set the start time of the contrast imaging based on a time point when the value of the hemoglobin amount becomes equal to or greater than the threshold value and a positional relationship between the first region and the second region.

(Appendix 13)
The blood vessel at the first site may be the common carotid artery, the radial artery, the femoral artery, the popliteal artery, the posterior tibial artery, or the dorsalis pedis artery.

(Appendix 14)
The blood information is first blood information,
The acquisition unit further acquires second blood information related to a change in an amount of hemoglobin contained in blood in a blood vessel in a third part of the subject,
The setting unit may set the imaging condition based on the first blood information and the second blood information.

(Appendix 15)
an analysis unit that generates a first time-density curve in which the hemoglobin amount corresponds to time by analyzing the first blood information, and generates a second time-density curve by analyzing the second blood information;
Further comprising:
The setting unit may set the imaging condition based on the first time density curve and the second time density curve.

(Appendix 16)
The imaging unit may perform the contrast imaging using X-ray computed tomography or magnetic resonance imaging.

(Appendix 17)
an acquisition unit that acquires blood information related to a change in the amount of hemoglobin contained in blood in blood vessels at a site of the subject;
an analysis unit that generates a time-concentration curve that correlates the hemoglobin amount with time by analyzing the blood information;
a determination unit for determining the presence or absence of a disease by comparing the time-density curve with a given time-density curve;
A medical information processing device comprising:

(Appendix 18)
obtaining blood information relating to a change in hemoglobin content in blood vessels at a first location of the subject;
setting imaging conditions for contrast imaging of a second region of the subject based on the blood information;
performing the contrast imaging based on the imaging conditions;
A medical image diagnostic method comprising:

REFERENCE SIGNS LIST 1 Medical image diagnostic device 1A X-ray CT device 1B Magnetic resonance imaging device 2 Blood information acquisition device 2A Optical imaging device 3 Injector 10, 10-2 Platform device 11 X-ray tube 12 X-ray detector 13 Rotating frame 14 X-ray high voltage device 15 Control device 16 Wedge filter 17 Collimator 18 DAS
19 Opening 21 Gradient magnetic field power supply 23 Transmission circuit 25 Reception circuit 27 Bed driving device 29 Sequence control circuit 30, 30-2 Bed device 31, 31-2 Base 33, 33-2 Top board 41 Static magnetic field magnet 43 Gradient magnetic field coil 45 Transmission coil 47 Reception coil 50, 50-2, 50-3 Medical information processing device 51 Processing circuit 511 System control function 512 Acquisition function 513 Analysis function 514 Setting function 515 Judgment function 516 Display control function 52 Memory 53 Display 54 Input interface 55 Communication interface 600, 800, 1100 Display screen 610 Monitoring image 620 Indoor image 630 Monitoring information 640, 700, 840, 1140, 1400 Analysis result 810, 1110 Positioning image 820, 1120 CT images 830, 1130 Scan information 841, 1141 Designator BV Blood vessel P Subject Po1, Po2, Po3, Po4, Po5, Po6, Po7 Installation position R Examination room R1, R2, R3, R4 Region ROI Region of interest ROIm Monitoring region of interest Tp, Tp1, Tp2, Ts, Ts1, Ts2 Time

Claims (18)

an acquisition unit that acquires blood information related to a change in an amount of hemoglobin contained in blood in a blood vessel at a first site of a subject;
a setting unit that sets imaging conditions for contrast imaging of a second region of the subject based on the blood information;
and an imaging unit that performs the contrast imaging based on the imaging conditions. an analysis unit that generates a time-concentration curve that correlates the hemoglobin amount with time by analyzing the blood information,
the setting unit sets the imaging condition based on the time-density curve.
The medical image diagnostic apparatus according to claim 1 . the blood information is an image obtained by optically photographing the first site,
The analysis unit generates the time-density curve by analyzing the image.
The medical image diagnostic apparatus according to claim 2 . The method further includes an optical photographing device that photographs the first portion to obtain the image.
The medical image diagnostic apparatus according to claim 3 . the blood information is sensor information indicating a value of the hemoglobin amount obtained by sensing a blood vessel in the first region,
The analysis unit generates the time-density curve based on the sensor information.
The medical image diagnostic apparatus according to claim 2 . A sensor that acquires the sensor information by sensing a blood vessel at the first site.
The medical image diagnostic apparatus according to claim 5 . a memory that stores the time-density curve and examination information including information of the subject in association with each other.
The medical image diagnostic apparatus according to claim 2 . said memory stores a given time-concentration curve;
The acquisition unit acquires the given time-density curve from the memory;
The setting unit sets the imaging condition based on the given time-density curve.
The medical image diagnostic apparatus according to claim 7. The given time-concentration curve is a historical time-concentration curve of the subject or a typical time-concentration curve of a healthy individual.
The medical image diagnostic apparatus according to claim 8. the imaging condition includes a threshold value related to the value of the hemoglobin amount,
a determination unit that determines whether or not the amount of hemoglobin is equal to or greater than the threshold value after a contrast agent is injected into the blood vessel of the subject,
The imaging unit performs the contrast imaging based on a time point when the value of the hemoglobin amount becomes equal to or greater than the threshold value.
The medical image diagnostic apparatus according to claim 1 . the setting unit sets a time point when the amount of hemoglobin becomes equal to or greater than the threshold value as the start time of the contrast imaging.
The medical image diagnostic apparatus according to claim 10. the setting unit sets a start time of the contrast imaging based on a time point when the value of the hemoglobin amount becomes equal to or greater than the threshold value and a positional relationship between the first region and the second region.
The medical image diagnostic apparatus according to claim 10. The blood vessel at the first site is a common carotid artery, a radial artery, a femoral artery, a popliteal artery, a posterior tibial artery, or a dorsalis pedis artery;
The medical image diagnostic apparatus according to claim 1 . The blood information is first blood information,
The acquisition unit further acquires second blood information related to a change in an amount of hemoglobin contained in blood in a blood vessel in a third part of the subject,
The setting unit sets the imaging condition based on the first blood information and the second blood information.
The medical image diagnostic apparatus according to claim 1 . an analysis unit that generates a first time-density curve in which the hemoglobin amount corresponds to time by analyzing the first blood information, and generates a second time-density curve by analyzing the second blood information,
the setting unit sets the imaging condition based on the first time density curve and the second time density curve.
The medical image diagnostic apparatus according to claim 14. The imaging unit performs the contrast imaging using X-ray computed tomography or magnetic resonance imaging.
The medical image diagnostic apparatus according to any one of claims 1 to 15. an acquisition unit that acquires blood information related to a change in the amount of hemoglobin contained in blood in blood vessels at a site of the subject;
an analysis unit that generates a time-concentration curve that correlates the hemoglobin amount with time by analyzing the blood information;
a determination unit that determines the presence or absence of a disease by comparing the time-density curve with a given time-density curve. obtaining blood information relating to a change in hemoglobin content in blood vessels at a first location of the subject;
setting imaging conditions for contrast imaging of a second region of the subject based on the blood information;
performing the contrast imaging based on the imaging conditions.