Pet device, pet-ct device, information generation display method, and storage medium

Abstract

The PET apparatus according to the embodiment includes multiple PET detector rings, an acquisition unit, a generation unit, and a display control unit. The multiple PET detector rings are movable relative to the top plate along a central axis direction within an opening into which a top plate for placing a sample is inserted. The acquisition unit acquires position information along the central axis direction for each of the multiple PET detector rings. Based on the position information, the generation unit generates display information related to the positions of the multiple PET detector rings. The display control unit displays the display information on a display screen.

Description

Technical Field

[0001] The embodiments described herein generally relate to PET devices, PET-CT devices, information generation and display methods, and non-volatile storage media capable of being read by a computer that stores information generation and display programs. Background Technology

[0002] Traditionally, PET (Positoron Emission Tomography) devices consist of PET rings in which PET detectors for detecting photons are arranged in a ring. In recent years, PET devices with multiple PET rings have been developed. These multiple PET rings are sometimes configured to move freely along the body axis. When multiple PET rings can move freely, the positions of each ring can be appropriately varied according to the length of the imaging range along the body axis of the subject.

[0003] However, in cases where whole-body imaging or imaging of specific areas of the subject is performed, if the user moves multiple PET rings accordingly to the imaging range, it can be difficult to accurately determine the position of the PET rings. Therefore, when the PET rings are positioned arbitrarily, it can be challenging to move them effectively. Summary of the Invention

[0004] The PET apparatus according to the embodiment includes multiple PET detector rings, an acquisition unit, a generation unit, and a display control unit. The multiple PET detector rings are movable relative to the top plate along a central axis direction within an opening into which a top plate for placing a sample is inserted. The acquisition unit acquires position information along the central axis direction for each of the multiple PET detector rings. Based on the position information, the generation unit generates display information related to the positions of the multiple PET detector rings. The display control unit displays the display information on a display screen. Attached Figure Description

[0005] Figure 1 This is a diagram showing the configuration of the PET-CT device according to the first embodiment.

[0006] Figure 2 This is a diagram illustrating an example of the configuration of multiple PET detector rings corresponding to the imaging range according to the first embodiment.

[0007] Figure 3 This is a flowchart illustrating an example of the information generation and display processing involved in the first embodiment.

[0008] Figure 4 This is a diagram illustrating an example of display information displayed on a display screen according to the first embodiment.

[0009] Figure 5 This is a diagram illustrating an example of the display information for the scout image as it is swiped from the head to the legs of the subject in step S306 according to the first embodiment.

[0010] Figure 6 This is a diagram illustrating an example of the display information for the scout image as it moves from the subject's shoulder to the waist in step S306 according to the first embodiment.

[0011] Figure 7 This indicates that the user involved in the first embodiment... Figure 4 The diagram shows an example of an operation that displays information.

[0012] Figure 8 This is a diagram illustrating an example of a count rate mapping displayed on a display, as described in the first application example of the first embodiment.

[0013] Figure 9 This is a diagram illustrating an example of the difference between the first scan and the second scan when multiple PET detector rings are configured for the subject, according to the fourth application example of the first embodiment.

[0014] Figure 10 This is a diagram showing an example of the projection position of a laser beam projected from a light emitter in a variation of the first embodiment.

[0015] Figure 11 This is a diagram illustrating an example of the photographing area of ​​the first camera and the photographing area of ​​the second camera in a variation of the first embodiment.

[0016] Figure 12 This is a flowchart illustrating an example of the operation of multiple PET detector rings in a PET-CT examination according to the second embodiment.

[0017] Figure 13 This is a diagram illustrating an example of the positions of multiple PET detector rings that are retracted outside the radiation range of X-rays according to the second embodiment. Detailed Implementation

[0018] The PET apparatus according to the embodiment includes multiple PET detector rings, an acquisition unit, a generation unit, and a display control unit. The multiple PET detector rings are movable relative to the top plate along a central axis direction within an opening into which a top plate for placing a sample is inserted. The acquisition unit acquires position information along the central axis direction for each of the multiple PET detector rings. Based on the position information, the generation unit generates display information related to the positions of the multiple PET detector rings. The display control unit displays the display information on a display screen.

[0019] Hereinafter, a PET (Positoron Emission Tomography) apparatus, a PET-CT (Computed Tomography) apparatus, an information generation and display method, and an information generation and display program will be described in detail with reference to the accompanying drawings. In the following embodiments, portions marked with the same reference numerals are assumed to perform the same operations, and repeated descriptions are suitably omitted. Furthermore, the PET apparatus, PET-CT apparatus, information generation and display method, and information generation and display program involved in this application are not limited to the embodiments shown below.

[0020] The PET device according to this embodiment has a camera mechanism for performing PET imaging (PET scanning and PET scout). Examples of such PET devices include PET devices with only PET imaging function, PET-CT devices with both a PET camera mechanism and an X-ray CT (Computed Tomography) camera mechanism, and PET-MR devices with both a PET camera mechanism and an MR (Magnetic Resonance) camera mechanism. Hereinafter, for specific explanation, this embodiment will be described as a PET-CT device. In the PET camera mechanism of this embodiment, multiple PET detector rings are provided.

[0021] (First Embodiment)

[0022] Figure 1 This is a diagram showing the configuration of the PET-CT apparatus 1 according to the first embodiment. (See diagram below.) Figure 1 As shown, the PET-CT device 1 includes a PET gantry 10, a CT gantry 30, an examination bed 50, and a control console 70. The PET gantry 10, CT gantry 30, and examination bed 50 are typically located in a common examination room. The control console 70 is located in a control room adjacent to the examination room. The PET gantry 10 is an imaging device for performing PET imaging (PET scan and / or PET scout) on a subject P. The CT gantry 30 is an imaging device for performing X-ray CT imaging (CT scan and / or CT scout) on a subject P. The examination bed 50 supports a top plate 53 on which the subject P is placed, allowing for free movement. The control console 70 is a computer that controls the PET gantry 10, CT gantry 30, and examination bed 50.

[0023] The PET stand 10, for example, includes multiple PET detector rings, a signal processing circuit 13, a simultaneous counting circuit 15, and a ring moving mechanism 16. Figure 1Although only one PET detector ring 11 is shown, the actual PET stand 10 houses multiple PET detector rings that are movable relative to the top plate 53 along the central axis (Z direction) within the hole 20 into which the top plate 53 for placing the subject P is inserted. For example, a signal processing circuit 13 and a simultaneous counting circuit 15 are provided for each of the multiple PET detector rings. The ring moving mechanism 16 supports each of the multiple PET detector rings so that they can move along the central axis (Z direction) of the hole 20. Furthermore, the PET stand 10 and the CT stand 30 can also be housed in the same housing.

[0024] The PET detector ring 11 has multiple gamma-ray detectors 17 arranged in a circle around the central axis Z. The gamma-ray detectors 17 are also referred to as PET detectors. An image field of view (FOV) is set at the opening of the PET detector ring 11. The subject P is positioned such that the imaging portion of the subject P is included in the image field of view. A reagent labeled by a positron-emitting nuclide is introduced into the subject P. The positrons emitted from the positron-emitting nuclide annihilate with surrounding electrons. Through annihilation, a pair of annihilated gamma rays are generated. The gamma-ray detectors 17 detect the annihilated gamma rays emitted from within the subject P. The gamma-ray detectors 17 generate an electrical signal corresponding to the amount of annihilated gamma rays detected. For example, the gamma-ray detectors 17 have multiple scintillators and multiple photomultiplier tubes. The scintillators receive annihilated gamma rays caused by radioactive isotopes within the subject P, generating scintillation light. The photomultiplier tubes generate an electrical signal corresponding to the amount of scintillation light. The generated electrical signal is supplied to the signal processing circuit 13.

[0025] The signal processing circuit 13 generates single-event data based on the electrical signal output from the gamma ray detector 17. Specifically, the signal processing circuit 13 applies, for example, detection timing measurement processing, position calculation processing, and energy calculation processing to the electrical signal. The signal processing circuit 13 is implemented by an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), other complex programmable logic devices (CPLDs), or simple programmable logic devices (SPLDs) configured to perform detection timing measurement processing, position calculation processing, and energy calculation processing.

[0026] In the detection time measurement process, the signal processing circuit 13 measures the detection time when the gamma ray detector 17 detects the gamma ray. Specifically, the signal processing circuit 13 monitors the peak value of the electrical signal from the gamma ray detector 17 and measures the moment when the peak value exceeds a preset threshold as the detection time. In other words, the signal processing circuit 13 detects when the peak value exceeds the threshold, thereby detecting the annihilated gamma ray electrically. In the position calculation process, the signal processing circuit 13 calculates the incident position of the annihilated gamma ray based on the electrical signal from the gamma ray detector 17. The incident position of the annihilated gamma ray corresponds to the position coordinates of the scintillator into which the annihilated gamma ray is incident. In the energy calculation process, the signal processing circuit 13 calculates the energy value of the detected annihilated gamma ray based on the electrical signal from the gamma ray detector 17.

[0027] A correlation is established between the detection time data, position coordinate data, and energy value data associated with a single event. The combination of energy value data, position coordinate data, and detection time data associated with a single event is called single-event data. Single-event data is generated sequentially each time annihilation gamma rays are detected. The generated single-event data is supplied to the simultaneous counting circuit 15.

[0028] Simultaneous counting circuit 15 performs simultaneous counting processing on single-event data from signal processing circuit 13. As hardware, simultaneous counting circuit 15 is implemented by an ASIC, FPGA, CPLD, or SPLD configured to perform simultaneous counting processing. In simultaneous counting processing, simultaneous counting circuit 15 repeatedly identifies single-event data related to two single events within a predetermined time frame from the repeatedly supplied single-event data. The paired single events are inferred to originate from annihilation gamma rays generated from the same annihilation point. The paired single events are collectively referred to as simultaneous counting events. The line connecting the paired gamma ray detectors 17 (more specifically, scintillators) that detect the annihilation gamma rays is called the LOR (Line of Response). The event data related to the paired events constituting the LOR is called simultaneous counting event data. Simultaneous counting event data and single-event data are transmitted to console 70. Hereinafter, without specifically distinguishing between simultaneous counting event data and single-event data, they are collectively referred to as PET event data.

[0029] Furthermore, in the above configuration, the signal processing circuit 13 and the simultaneous counting circuit 15 are included in the PET stand 10, but this embodiment is not limited to this. For example, the simultaneous counting circuit 15, or both the signal processing circuit 13 and the simultaneous counting circuit 15, may be included in a device separate from the PET stand 10. In addition, either a single simultaneous counting circuit 15 can be provided for the multiple signal processing circuits 13 mounted on the PET stand 10, or the multiple signal processing circuits 13 mounted on the PET stand 10 can be divided into multiple groups, and a single simultaneous counting circuit 15 can be provided for each group.

[0030] Under the control of the movement control function 737 in the processing circuit 73 (described later), the ring moving mechanism 16 moves multiple PET detector rings along the central axis direction (Z direction) of the aperture 20. The ring moving mechanism 16 includes, for example, a ring support mechanism that supports the multiple PET detector rings so that they can move along the central axis direction (Z direction) of the aperture 20, a moving mechanism that moves the multiple PET detector rings within the ring support mechanism, and a drive mechanism that drives the moving mechanism. The ring support mechanism is implemented, for example, by a linear bearing disposed on the PET stand 10 along the central axis direction (Z direction) of the aperture 20. The means of implementing the ring support mechanism is not limited to linear bearings; various known bearings can be suitably utilized. The guide rail of the linear bearing is provided in a fixed frame in the PET stand 10 along the central axis direction (Z direction) of the aperture 20. Furthermore, in the linear bearing, a module traveling on the guide rail is equipped with a support frame that holds each of the multiple PET detector rings in a ring shape.

[0031] The moving mechanism is implemented by multiple rack and pinion pairs corresponding to multiple PET detector rings. The means of implementing the moving mechanism is not limited to rack and pinion pairs; known devices such as ball screws can be appropriately utilized. Multiple racks in the multiple rack and pinion pairs are arranged along the central axis (Z direction) of the hole 20 and are respectively connected to multiple retaining frames corresponding to the multiple PET detector rings. Multiple pinions mesh with multiple racks. For example, a rotary encoder for measuring the rotational speed of the pinion can also be provided on the pinion. In this case, the output from the rotary encoder is output to the processing circuit 73.

[0032] The drive mechanism is implemented, for example, by a motor. The rotating shaft of the motor is connected to a pinion, for example, via various gears. Furthermore, if no rotary encoder is provided on the pinion, a rotary encoder for measuring the rotational speed of the rotating shaft can be provided, for example, on the rotating shaft of the motor or on the various gears. In this case, the output from the rotary encoder is output to the processing circuit 73. The motor is driven according to the control signal of the motion control function 737. The pinion rotates due to the rotation of the motor, thereby moving the rack along the central axis direction (Z direction) of the aperture 20. Through the movement of the rack, multiple PET detector rings move along the central axis direction (Z direction) of the aperture 20.

[0033] Figure 2 This is a diagram illustrating an example of the configuration of multiple PET detector rings 101 corresponding to the imaging range. Figure 2 The diagram on the left shows an example of a state (hereinafter referred to as a dense state) DS in which multiple PET detector rings 101 are densely arranged. In the dense state DS, for example, multiple PET detector rings 101 are arranged to correspond to a short (narrow) imaging range from the neck to the waist, as the imaging range of the subject P. Figure 2 In the dense state DS shown, the spacing of two adjacent PET detector rings is 112 times greater than that of the other two. Figure 2 Other states are narrow. At this time, the PET stage 10 is able to acquire data with a high SNR (Signal-to-Noise Ratio) in a small region of interest of the subject P.

[0034] in addition, Figure 2 The central diagram illustrates an example of a whole-body configuration (WBS) in which multiple PET detector rings 101 are evenly distributed throughout the subject P. In the WBS, multiple PET detector rings 101 are arranged to cover the imaging range of the subject P, corresponding to the (wide) imaging range of the whole body length. Figure 2 In the whole-body configuration (WBS) shown, data from a large region of interest for the subject P can be acquired over a longer imaging range. At this time, the spacing 112 between adjacent PET detector rings is... Figure 2 The dense state DS width in the middle.

[0035] in addition, Figure 2 The diagram on the right shows an example of a partially dense PDS (partially dense state) where a portion of the multiple PET detector rings 101 are concentrated at a specific location on the subject P. In a partially dense PDS, the whole body is covered as the imaging range for the subject P, and the density of the multiple PET detector rings 101 on the chest of the subject P is increased compared to other locations. Figure 2As shown, the plurality of PET detector rings 101 in this embodiment can be appropriately moved along the central axis direction (Z direction) of the hole 20.

[0036] For example, multiple PET detector rings 101 are configured based on specific characteristics of the subject P, including the subject P's age, sex, and height, the attenuation of radiation within the subject, the purpose of the examination, and the imaging range set by the user. In this way, specific areas of the subject P are defined based on associated factors of the subject P. For example, in a partially dense PDS state, the interval 112' between two adjacent PET detector rings related to PET imaging of a specific area corresponds to a first distance, and the interval 112" between two adjacent PET detector rings related to PET imaging of other specific areas of the subject P becomes a second distance, longer than the first distance. Figure 2 As shown in the partial dense state PDS, when the region of interest includes the upper respiratory tract of the subject P, the spacing 112' of the PET detector rings in the upper trunk is set to be shorter than the spacing 112" of the PET detector rings in the lower limbs.

[0037] like Figure 1 As shown, the CT gantry 30 has a CT camera assembly. The CT camera assembly performs CT scans on the subject P. Furthermore, the CT camera assembly can also perform X-ray-based scout imaging on the subject P. The CT camera assembly includes an X-ray tube 31, an X-ray detector 32, a rotating frame 33, an X-ray high-voltage device 34, a CT control device 35, a wedge 36, a collimator 37, and a DAS 38.

[0038] X-ray tube 31 generates X-rays. Specifically, X-ray tube 31 has a vacuum tube that holds a cathode that generates thermionic electrons and an anode that receives the thermionic electrons flying from the cathode and generates X-rays. X-ray tube 31 is connected to X-ray high-voltage device 34 via a high-voltage cable. A tube voltage is applied between the cathode and anode by X-ray high-voltage device 34. By applying tube voltage, thermionic electrons fly from the cathode toward the anode. Current flows through the tube as the thermionic electrons fly from the cathode toward the anode. By applying high voltage and supplying filament current from X-ray high-voltage device 34, thermionic electrons fly from the cathode toward the anode, colliding with the anode. Thus, X-rays are generated.

[0039] X-ray detector 32 detects X-rays generated from X-ray tube 31 that have passed through the subject P. X-ray detector 32 outputs an electrical signal to DAS 38 corresponding to the dose of the detected X-rays. X-ray detector 32 has a structure in which multiple rows of X-ray detection elements arranged in the channel direction are arranged along the slice direction (also called the row direction). X-ray detector 32 is, for example, an indirect conversion type detector having a grid, a scintillator array, and a photodetector array. The scintillator array has multiple scintillators. The scintillator outputs light with a quantity corresponding to the incident X-ray quantity. The grid is disposed on the X-ray incident surface side of the scintillator array. The grid has an X-ray shielding plate that absorbs scattered X-rays. The photodetector array converts the light output from the scintillators into an electrical signal corresponding to the quantity of that light. For example, a photodiode or photomultiplier tube can be used as the photodetector. Alternatively, X-ray detector 32 can also be implemented as a direct conversion type detector (semiconductor detector) having a semiconductor element that converts incident X-rays into an electrical signal.

[0040] The rotating frame 33 is an annular frame that supports the X-ray tube 31 and the X-ray detector 32, enabling them to rotate about the rotation axis Z. Specifically, the rotating frame 33 supports the X-ray tube 31 and the X-ray detector 32 opposite to each other. The rotating frame 33 is supported by a fixed frame (not shown) and is able to rotate about the rotation axis Z. Under the control of the CT control device 35, the rotating frame 33 rotates about the rotation axis Z. As a result, the X-ray tube 31 and the X-ray detector 32 rotate about the rotation axis Z. The rotating frame 33 receives power from the drive mechanism of the CT control device 35 and rotates about the rotation axis Z at a certain angular velocity. An image field of view (FOV) is provided at the opening of the rotating frame 33.

[0041] Furthermore, in this embodiment, the rotation axis of the rotating frame 33 in the non-tilted state or the length direction of the top plate 53 of the examination bed 50 is defined as the Z-axis direction, the axis direction that is orthogonal to the Z-axis direction and horizontal relative to the ground is defined as the X-axis direction, and the axis direction that is orthogonal to the Z-axis direction and perpendicular to the ground is defined as the Y-axis direction.

[0042] The X-ray high-voltage device 34 includes electrical circuits such as a transformer and a rectifier. Furthermore, the X-ray high-voltage device 34 includes a high-voltage generating device that generates the high voltage applied to the X-ray tube 31 and the filament current supplied to the X-ray tube 31, and an X-ray control device that controls the output voltage corresponding to the X-rays irradiated by the X-ray tube 31. The high-voltage generating device can be either a transformer or an inverter. The X-ray high-voltage device 34 can be installed in either a rotating frame 33 within the CT gantry 30 or a fixed frame (not shown) within the CT gantry 30.

[0043] The wedge 36 adjusts the dose of X-rays irradiated onto the subject P. Specifically, the wedge 36 attenuates the X-rays so that the dose of X-rays irradiated onto the subject P from the X-ray tube 31 is a predetermined distribution. For example, the wedge 36 can be a metal plate such as aluminum, such as a wedge filter or a bow-tie filter.

[0044] Collimator 37 limits the irradiation range of the X-rays transmitted through wedge 36. Collimator 37 supports multiple lead plates that shield the X-rays so that they can slide and adjust the shape of the slit formed by the multiple lead plates.

[0045] The DAS (Data Acquisition System) 38 reads an electrical signal corresponding to the dose of X-rays detected by the X-ray detector 32. The DAS 38 amplifies the read electrical signal at a variable magnification. Next, the DAS 38 accumulates the amplified electrical signal during the viewing period, thereby acquiring raw CT data with digital values ​​corresponding to the dose of X-rays during that viewing period. The DAS 38 is implemented, for example, by an ASIC equipped with circuitry capable of generating raw CT data. The raw CT data is transmitted to the control console 70 via a non-contact data transmission device or the like.

[0046] The CT control unit 35 controls the X-ray high-voltage device 34, DAS 38, etc., for X-ray CT imaging via the camera control function 733 of the processing circuit 73 of the control console 70. The CT control unit 35 includes a processing circuit with a CPU (Central Processing Unit) and drive mechanisms such as motors and actuators. The processing circuit includes processors such as CPUs and MPUs (Micro-Processing Units) and memories such as ROM (Read-Only Memory) and RAM (Random Access Memory) as hardware resources. Alternatively, the CT control unit 35 can also be implemented using ASICs, FPGAs, CPLDs, or SPLDs.

[0047] In addition, the CT stand 30 has various types, such as the Rotate / Rotate-Type (3rd generation CT) where the X-ray generating unit and the X-ray detection unit are integrated and rotate around the subject, and the Stationary / Rotate-Type (4th generation CT) where multiple X-ray detection elements are fixed in a ring array and only the X-ray generating unit rotates around the subject. Any type can be applied to one implementation.

[0048] like Figure 1 As shown, the examination table 50 holds the subject P, which is the object to be scanned, and moves the subject. The examination table 50 is shared by the PET gantry 10 and the CT gantry 30.

[0049] The examination table 50 includes a base 51, a support frame 52, a top plate 53, and an examination table drive unit 54. The base 51 is disposed on the ground. The base 51 is a housing that supports the support frame 52 and is movable in a direction perpendicular to the ground (Y-axis direction). The support frame 52 is a frame disposed on the upper part of the base 51. The support frame 52 supports the top plate 53 and is slidable along the central axis Z. The top plate 53 is a flexible plate for placing the subject P.

[0050] The examination bed drive unit 54 is housed within the housing of the examination bed 50. The examination bed drive unit 54 is a motor or actuator that generates power to move the support frame 52 and the top plate 53 on which the subject P is placed. The examination bed drive unit 54 operates according to the control of the control console 70, etc.

[0051] The PET stand 10 and CT stand 30 are configured such that the central axis Z of the opening of the PET stand 10 is approximately aligned with the central axis Z of the opening of the CT stand 30. The examination bed 50 is configured such that the major axis of the top plate 53 is parallel to the central axis Z of the openings of the PET stand 10 and CT stand 30. The CT stand 30 and PET stand 10 are arranged, for example, in the order of CT stand 30 and PET stand 10, starting from the side closest to the examination bed 50.

[0052] like Figure 1 As shown, the console 70 includes a PET data memory 71, a CT data memory 72, a processing circuit 73, a display 74, a memory 75, and an input interface 76. For example, data communication between the PET data memory 71, the CT data memory 72, the processing circuit 73, the display 74, the memory 75, and the input interface 76 is performed via a bus.

[0053] The PET data storage device 71 is a storage device that stores single-event data and simultaneously counted event data transmitted from the PET rack 10. The PET data storage device 71 can be a storage device such as an HDD (Hard Disk Drive), SSD (Solid State Drive), or an integrated circuit storage device.

[0054] The CT data storage device 72 is a storage device that stores the raw CT data transmitted from the CT gantry 30. The CT data storage device 72 can be a storage device such as an HDD, SSD, or integrated circuit storage device.

[0055] The processing circuit 73 includes processors such as CPU, MPU, and GPU (Graphics Processing Unit), as well as memories such as ROM and RAM, as hardware resources. The processing circuit 73 executes various programs read from the memory to implement reconstruction function 731, image processing function 732, camera control function 733, acquisition function 734, generation function 735, display control function 736, and motion control function 737. In other words, the processing circuit 73 is equivalent to a processor that reads programs from memory and executes them to implement the functions corresponding to each program. In other words, the processing circuit 73, having read the state of each program, has the function corresponding to the read program. Furthermore, the reconstruction function 731, image processing function 732, camera control function 733, acquisition function 734, generation function 735, display control function 736, and motion control function 737 can be mounted on a single substrate or distributed across multiple substrates. The processing circuit 73, which implements the reconstruction function 731, image processing function 732, camera control function 733, acquisition function 734, generation function 735, display control function 736, and motion control function 737, corresponds to the reconstruction unit, image processing unit, camera control unit, acquisition unit, generation unit, display control unit, and motion control unit, respectively.

[0056] In reconstruction function 731, processing circuit 73 reconstructs a PET image representing the distribution of positron-emitting nuclides emitted towards the subject P based on simultaneous count event data. Additionally, processing circuit 73 reconstructs a CT image representing the spatial distribution of CT values ​​related to the subject P based on raw CT data. Existing image reconstruction algorithms such as FBP (Filtered Back Projection) and successive approximation reconstruction methods can be used as image reconstruction algorithms. Furthermore, processing circuit 73 can also generate PET-related localization images based on PET event data, or CT-related localization images (CT scout images) based on raw CT data.

[0057] In image processing function 732, processing circuit 73 applies various image processing techniques to the PET and CT images reconstructed by reconstruction function 731. For example, processing circuit 73 applies 3D image processing techniques such as volume rendering, surface rendering, pixel value projection processing, MPR (Multi-Planer Reconstruction) processing, and CPR (Curved MPR) processing to the PET and CT images to generate display images.

[0058] In the camera control function 733, the processing circuit 73 synchronously controls the PET stage 10 and the examination table 50 for PET imaging. Similarly, the camera control function 733 synchronously controls the CT stage 30 and the examination table 50 for CT imaging. When performing both PET and CT imaging consecutively, the camera control function 733 synchronously controls the PET stage 10, the CT stage 30, and the examination table 50. Furthermore, the processing circuit 73 can perform positioning scans based on the PET stage 10 (hereinafter referred to as PET positioning scans) and positioning scans based on the CT stage 30 (hereinafter referred to as CT positioning scans). For PET positioning scans, the camera control function 733 synchronously controls the PET stage 10 and the examination table 50. For CT positioning scans, the camera control function 733 synchronously controls the CT stage 30 and the examination table 50.

[0059] Processing circuit 73 acquires position information in the central axis direction (Z direction) for each of the multiple PET detector rings via acquisition function 734. For example, acquisition function 734 acquires the position information of each of the multiple PET detector rings based on the output of a rotary encoder mounted on a pinion gear or the output of a rotary encoder mounted on the rotating shaft of a motor in the drive mechanism. Furthermore, the source of the position information is not limited to the aforementioned rotary encoder; it can also be a known position sensor. Acquisition function 734 stores the acquired position information in memory 75. Additionally, acquisition function 734 also acquires information related to the subject P. Here, information related to the subject P may be, for example, a scout image generated by scout photography (CT scout or PET scout) performed on the subject P. Acquisition function 734 stores the acquired information related to the subject P in memory 75.

[0060] The processing circuit 73 generates display information related to the positions of the plurality of PET detector rings 101 based on the acquired position information through the generation function 735. For example, the generation function 735 establishes a correspondence between the positions of the plurality of PET detector rings 101 and information related to the subject P to generate the display information. The display information is, for example, information indicating the relative positional relationship of the plurality of PET detector rings 101 with respect to the subject P placed on the top plate 53. At this time, the display information has the ring display object indicating the position of the plurality of PET detector rings 101 as the ring display object of each of the plurality of PET detector rings. In addition, the display information may also include the position of the X-ray detector 32 relative to the subject P.

[0061] Additionally, the displayed information may also include: information indicating the radiographic range for the subject P in accordance with the instructions given by the user via the input interface 76 or the examination site in the examination order output from the Radiology Information System (RIS) or Hospital Information System (HIS) (e.g., a dashed box or radiographic pattern indicating the radiographic object).

[0062] Processing circuit 73, through generation function 735, selects a photographic mode (hereinafter referred to as the recommended mode) from multiple photographic modes, including mode 1 and mode 2, that is close to the input photographic range based on the photographic range input via input interface 76. Mode 1 is a photographic mode in which multiple PET detector rings 101 are arranged equally at predetermined intervals corresponding to the body length of the subject P. Mode 1 corresponds, for example, to... Figure 2 The WBS (Whole Body Layout) shows the configuration of multiple PET detector rings 101. The second mode is an imaging mode in which the multiple PET detector rings 101 are densely arranged along the central axis, corresponding to various locations among the multiple sites of the subject P. In the case where the imaging range is from the neck to the waist, the second mode corresponds to... Figure 2 The partial dense state PDS shows the configuration of multiple PET detector rings 101.

[0063] The processing circuit 73, through the display control function 736, displays the display information generated by the generation function 735 on the display 74. Furthermore, if a user inputs an operation to move a ring display object (hereinafter referred to as a movement operation) via the input interface 76, the display control function 736 updates the display information and displays it on the display 74 along with the movement of the ring display object. Additionally, if a recommended mode is selected from multiple photography modes via the generation function 735, the display control function 736, in addition to the display information, displays the selected photography mode (recommended mode) and the corresponding scan range on the display 74. The scan range is represented in the display information, for example, by the arrangement of multiple ring display objects corresponding to the recommended mode and / or by a frame for the scout image. The display method in the display information will be explained in the information generation and display processing described later.

[0064] The processing circuit 73 controls the movement of multiple PET detector rings 101 via the movement control function 737. For example, after determining the movement of the ring display object shown on the display 74, the movement control function 737 moves the PET detector ring corresponding to the moved ring display object along the central axis direction based on the moved ring display object and its position information.

[0065] Specifically, if a determination instruction to move the ring display object is input via input interface 76, the movement control function 737 determines the position within the PET rack 10 corresponding to the position of the moved ring display object in the display information, and the position information of the PET detector ring corresponding to the moved ring display object. Next, the movement control function 737 calculates the amount of movement of the PET detector ring (e.g., the rotational speed of the pinion gear or the rotational speed of the motor) based on the position information associated with the PET detector ring and the determined position. Then, the movement control function 737 controls the ring movement mechanism 16 (more specifically, the drive mechanism) to move the PET detector ring by the calculated amount of movement.

[0066] Under the control of the display control function 736 in the processing circuit 73, the display 74 displays various information, such as display information generated by the generation function 735. As the display 74, for example, a CRT (Cathode Ray Tube) display, a liquid crystal display (LCD), an organic EL (Organic Electro Luminescence) display, an LED (Light Emitting Diode) display, a plasma display, or any other display known in the art can be suitably used. Furthermore, the display 74 can be a desktop type or a tablet computer terminal capable of wireless communication with the control console 70. The display 74 corresponds to the display unit.

[0067] The memory 75 is a storage device such as an HDD, SSD, or integrated circuit storage device that stores various types of information. Alternatively, the memory 75 can also be a drive device for reading and writing various types of information between removable storage media such as CD (Compact Disc)-ROM drives, DVD (Digital Versatile Disc) drives, and flash memory. The memory 75 stores, for example, various data related to the execution of functions such as storage and reconstruction 731, image processing 732, camera control 733, acquisition 734, generation 735, display control 736, and motion control 737. The memory 75 stores position information acquired through the acquisition function 734. The memory 75 stores display information generated through the generation function 735. The memory 75 stores the configuration modes of the multiple PET detector rings 101, such as the first mode and the second mode. The memory 75 executes various programs related to the storage and reconstruction function 731, image processing function 732, camera control function 733, acquisition function 734, generation function 735, display control function 736, and motion control function 737.

[0068] The input interface 76 receives various input operations from the user (e.g., instructions to execute PET scans, instructions to execute CT scans, selection of imaging range, etc.), converts the received input operations into electrical signals, and outputs them to the processing circuit 73. For example, the input interface 76 can be suitably equipped with a mouse, keyboard, trackball, switch, button, joystick, touchpad, or touch panel display. Furthermore, in this embodiment, the input interface 76 is not limited to physical operating components such as a mouse, keyboard, trackball, switch, button, joystick, touchpad, or touch panel display. For example, a processing circuit that receives electrical signals corresponding to input operations from an external input device separate from the device and outputs these electrical signals to the processing circuit 73 is also included in the example of the input interface 76. Additionally, the input interface 76 can also be configured as a tablet computer terminal or the like capable of wireless communication with the control console 70. The input interface 76 corresponds to the input section.

[0069] The above describes the overall structure of PET-CT device 1. The following will use... Figures 3 to 7 This describes the information generation and display process. The information generation and display process generates and displays display information related to the multiple PET detector rings 101 based on the position information associated with each of the multiple PET detector rings. Figure 3 This is a flowchart illustrating an example of the information generation, display, and processing process.

[0070] (Information generation, display, and processing)

[0071] (Step S301)

[0072] Processing circuit 73 acquires information related to the subject P through acquisition function 734. For example, prior to this step, processing circuit 73 performs scout imaging (CT scout or PET scout) on subject P through camera control function 733. As a result, processing circuit 73 generates a scout image of subject P through reconstruction function 731 or image processing function 732. Next, in this step, processing circuit 73 acquires the scout image as information related to subject P through acquisition function 734.

[0073] (Step S302)

[0074] Processing circuit 73 acquires position information in the central axis direction for each of the multiple PET detector rings via acquisition function 734. For example, acquisition function 734 acquires the position information of each of the multiple PET detector rings based on the output of the rotary encoder in ring movement mechanism 16.

[0075] (Step S303)

[0076] The processing circuit 73, through the generation function 735, establishes a correspondence between multiple PET detector rings 101 and information related to the subject P, and generates display information related to the multiple PET detector rings 101 based on the position information. Specifically, the generation function 735 overlays the ring display object onto the scout image, which serves as information associated with the subject P, at a position based on the position information, and generates display information. At this time, the generation function 735 can also add a frame representing the top plate 53 on the back of the scout image of the subject P to the display information. In addition, the generation function 735 can also further overlay frames representing the PET gantry 10 and / or the CT gantry 30, and frames representing the X-ray detector 32, etc., onto the scout image based on the position information, and generate display information. Alternatively, the generation function 735 can use the outline of the scout image as information related to the subject P instead of the scout image of the subject P, and generate display information.

[0077] (Step S304)

[0078] The processing circuit 73 displays the information on the display 74 via the display control function 736. At this time, by means of instructions given by the user via the input interface 76, each of the multiple ring display objects in the display information can be moved appropriately along the central axis direction (the long axis direction of the top plate 53) in the display information.

[0079] Figure 4 This is a diagram illustrating an example of display information DI shown on the monitor 74. For example... Figure 4 As shown, the display information DI shows the scout image SI of the subject P, the four ring display objects RDO corresponding to the four PET detector rings, and the imaging mode IM. Figure 4 As shown, on the scout image SI of the subject P, four rings are overlaid to display the object RDO according to its position information. Figure 4 As shown, the display of the four ring display objects RDO is equivalent to reflecting the positions of multiple PET detector rings 101 in the display information DI.

[0080] (Step S305)

[0081] If the shooting range is input via input interface 76 (step S305: Yes), then the process of step S306 is executed. If the shooting range is not input (step S305: No), then the process of step S308 is executed.

[0082] (Step S306)

[0083] The processing circuit 73 selects a recommended imaging mode (close to the input imaging range) from multiple imaging modes through the generation function 735. For example, if the user swipes along the head-to-tail direction of the subject P in the scout image SI in the display information DI, the generation function 735 determines the imaging range based on the swipe range and the length of the subject P in the head-to-tail direction in the scout image SI. Furthermore, the input of the imaging range is not limited to swiping; for example, known operations such as moving the cursor along the head-to-tail direction while clicking with a mouse, or rotating the scroll wheel while clicking with a mouse, can be used. The generation function 735 determines the imaging mode corresponding to the input imaging range as the recommended mode. Alternatively, the imaging mode selected by the user from the multiple imaging modes IM in the display information DI can also be set as the recommended mode. Additionally, the positions of the multiple ring display objects corresponding to the multiple imaging modes and the positions of the multiple PET detector rings 101 are pre-established and stored in the memory 75.

[0084] (Step S307)

[0085] The processing circuit 73 updates the display information DI according to the recommended mode using the display control function 736 and displays it on the display 74. For example, in addition to the display information, the display control function 736 also displays the selected imaging mode (recommended mode) and the corresponding scannable range on the display 74. Specifically, the display control function 736 highlights the imaging mode corresponding to the recommended mode among multiple imaging modes IM in the display information DI. Furthermore, the display control function 736 displays the configuration of multiple ring display objects RDOs at the positions of the multiple ring display objects RDOs corresponding to the recommended mode in the display information DI. The positions of the multiple ring display objects RDOs corresponding to the recommended mode, for example, correspond to the scannable range where PET scanning can be performed. Moreover, the scannable range is not limited to the positions of the multiple ring display objects RDOs corresponding to the recommended mode; for example, it can also be displayed as a frame for the scout image SI.

[0086] Figure 5 This diagram illustrates an example of the display information DI when the scout image SI is swiped from the head to the leg of the subject P in step S306. Swiping from the head to the leg of the subject P, as... Figure 5 The area shown corresponds to the user's desired shooting range. At this point, as... Figure 5 As shown, in the display information DI, the "full body" photography mode, which corresponds to the recommended mode (mode 1) RM, is highlighted among the multiple photography modes IM. Furthermore, as... Figure 5 As shown, in the display information DI, multiple ring display objects RDO are displayed in a positional relationship corresponding to the first mode.

[0087] Figure 6 This diagram illustrates an example of the display information DI shown in step S306 when the scout image SI moves from the shoulder to the waist of the subject P. The movement from the shoulder to the waist of the subject P is as follows... Figure 6 The area shown corresponds to the user's desired shooting range. At this point, as... Figure 6 As shown, in the display information DI, the "Chest" photography mode, which corresponds to the recommended mode (Mode 2) RM among multiple photography modes IM, is highlighted. Furthermore, as... Figure 6 As shown, in the display information DI, multiple ring display objects RDO are displayed as display information DI according to their positional relationship corresponding to the second mode.

[0088] (Step S308)

[0089] If a movement operation of the ring display object is input via input interface 76 (step S308: Yes), then the process of step S309 is executed. If no movement operation of the ring display object is input (step S308: No), then the process of step S310 is executed.

[0090] Figure 7 It means that the user is targeting Figure 4 The diagram shows an example of the operation performed by the display information DI. (See diagram for example.) Figure 7 As shown, the ring-shaped display object at the knee position in the scout image SI can be moved by the user's actions. Figure 7 As an example, this illustrates a scenario where a ring-shaped display object at the knee position in the scout image SI moves in the direction of the arrow due to user input. Specifically, the processing circuit 73 updates the display information DI and displays it on the monitor 74 via the display control function 736, in conjunction with the movement of the ring-shaped display object.

[0091] (Step S309)

[0092] The processing circuit 73, through the display control function 736, updates the display information and displays it on the display 74 in conjunction with the movement of the ring display object. For example, in Figure 7 In the context of the scout image SI, if a ring display object at the knee position in the scout image SI is moved to a ring display object at the abdomen position in the scout image SI due to user interaction, then the positional relationship between the multiple ring display objects and the scout image SI becomes as follows: Figure 6 The positional relationship is shown.

[0093] (Step S310)

[0094] If the position of the multiple PET detector rings 101 is determined by the user's instruction via input interface 76 (step S310: Yes), then the process of step S311 is executed. If the position of the multiple PET detector rings 101 is not determined (step S310: No), then the process after step S305 is repeated. The processes in steps S307 and S309 above are equivalent to prompting the user with a demonstration (demonstration animation) related to the movement of the PET detector rings.

[0095] (Step S311)

[0096] The processing circuit 73, through the movement control function 737, moves the PET detector ring corresponding to the moved ring display object along the central axis direction based on the moved ring display object and its position information. That is, the movement control function 737 feeds back the position of the ring display object as the position of the multiple PET detector rings 101. Furthermore, the processing circuit 73 can also update the display information DI according to the change in position information accompanying the movement of the PET detector rings via the display control function 736 and display it on the display 74. That is, in this step, the display control function 736 can also be linked to the movement of the PET detector rings, displaying the display information DI after the ring display object has been moved on the display 74. After the information generation and display processing is completed, PET imaging is performed on the subject P according to the user's instruction via the input interface 76.

[0097] The PET-CT apparatus 1 (or PET apparatus) described in the first embodiment above acquires position information in the central axis direction of each of the plurality of PET detector rings that can move relative to the top plate 53 along the central axis direction within the hole 20 into which the top plate 53 for placing the subject P is inserted. Based on the acquired position information, display information DI related to the position of the plurality of PET detector rings 101 is generated and displayed on the display 74. Alternatively, this embodiment may also acquire information related to the subject P, establish a correspondence between the position of the plurality of PET detector rings 101 and the information related to the subject P, and generate display information DI. Furthermore, this embodiment inputs an operation in the display information DI that moves the ring display object representing each of the plurality of PET detector rings.

[0098] Furthermore, after the position of the ring display object is determined, the PET-CT device 1 (or PET device) according to the first embodiment moves the PET detector ring corresponding to the moved ring display object along the central axis direction based on the moved ring display object and position information. Along with the operation of moving the ring display object, the display information DI is updated and displayed on the display 74.

[0099] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the first embodiment, the positions of multiple PET detector rings 101 can be displayed on the display 74, and the positions of the multiple PET detector rings 101 can be operated from the display 74. Furthermore, according to this embodiment, on the user-operable display 74, the positions of the multiple PET detector rings 101 can be overlaid as ring display objects on the scout image, which is the imaging result of CT scout or PET scout.

[0100] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the first embodiment, if the user operates the position of the ring display object on the display 74 in accordance with the desired imaging range, the scannable range can be displayed along with a demonstration of the movement of the multiple PET detector rings 101. Thus, if the user determines the position (coordinates) of the ring display object, this determined position can be fed back to the control of the multiple PET detector rings 101, causing the multiple PET detector rings 101 to move to the position determined by the user.

[0101] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the first embodiment, the positions of the plurality of PET detector rings 101 that can move relative to the top plate 53 are easily determined, and the position adjustments of the plurality of PET detector rings 101 can be easily performed. Thus, according to this embodiment, the burden on the user associated with operating the plurality of PET detector rings 101 can be reduced, and the throughput of examinations of the subject P can be increased. Furthermore, according to this embodiment, the clinical effectiveness of PET scans performed by the movable plurality of PET detector rings 101 can be maximized, and the image quality obtained by PET scans can be improved.

[0102] In addition, the PET-CT device 1 (or PET device) according to the first embodiment inputs the imaging range of the subject P in the display information DI, and selects an imaging mode close to the imaging range from a plurality of imaging modes including the first mode and the second mode based on the input imaging range. In addition to displaying the display information DI, the selected imaging mode (recommended mode) and the scannable range corresponding to the recommended mode are also displayed on the display 74.

[0103] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the first embodiment, by pre-preparing multiple imaging modes including a first mode and a second mode in the software (or memory 75), and determining the imaging mode with the closest imaging range from the pre-prepared multiple imaging modes based on the imaging range selected by the user, the applicable scanning range can be suggested to the user, and imaging mode can be proposed to the user. Therefore, according to this embodiment, the time for the user to select the imaging range and adjust the position of the multiple PET detector rings 101 can be shortened, and the efficiency of the workflow for examining the subject P can be improved.

[0104] (Application Example 1)

[0105] In this application example, during information generation and display processing, a count rate map representing the number of gamma rays counted per unit time in the multiple PET detectors is generated for each of the multiple PET detector rings 101 based on simultaneous count event data. In the display information DI, the generated count rate map is overlaid onto the ring display object RDO and displayed on the display 74. Furthermore, since the count rate in this application example is generated during PET imaging of the subject P, it can also be referred to as the real-time count rate. Specifically, the count rate is generated and displayed on the display information DI during PET scanning and / or PET scout. Additionally, the unit time can be preset to 30 seconds, 1 minute, etc., and can be arbitrarily set by the user through the input interface 76.

[0106] The processing circuit 73 acquires simultaneous count event data based on the outputs of multiple gamma-ray detectors (PET detectors) 17 mounted on each of the multiple PET detector rings via the acquisition function 734. For example, during PET imaging of a subject P, the acquisition function 734 acquires simultaneous count event data from the simultaneous counting circuit 15.

[0107] Processing circuit 73, through generation function 735, generates a count rate map for each of the multiple PET detector rings during PET imaging of the subject P, based on simultaneous count event data. For example, in each of the multiple PET detector rings, the count rate map is generated by adding (compressing) the counts of simultaneous count events obtained from two PET detectors positioned vertically opposite each other, forming a planar image. In this case, multiple pixels in the count rate map represent the positions of the PET detectors, and the pixel value of each pixel corresponds to a brightness value (or color value) representing the count rate. Furthermore, the count rate map is not limited to a planar image; for example, it can also be generated from a 3D image representing the count rate in units of the PET detectors, i.e., in units of detection channels, corresponding to the volume data of the subject P.

[0108] The processing circuit 73, through the display control function 736, overlays the count rate mapping onto the ring display object representing each PET detector ring in the multiple PET detector rings in the display information DI and displays it on the display 74. Figure 8 This is a diagram illustrating an example of a count rate mapping CRMI displayed on monitor 74. (See diagram for example.) Figure 8 As shown, the four count rate maps CRMI corresponding to the four PET detector rings are overlaid onto the four ring display objects RDO corresponding to the four PET detector rings for display. Figure 8 The count rate mapping shown in CRMI corresponds to individual cells in the PET detector, i.e., channels. Figure 8 In the diagram, the difference in count rate in the CRMI is represented by shading, but in reality, the magnitude of the count rate is represented by the difference in brightness values.

[0109] The PET-CT apparatus 1 (or PET apparatus) described in the first application example of the first embodiment above acquires simultaneous counting event data based on the outputs of multiple PET detectors mounted on each of the multiple PET detector rings. Based on the simultaneous counting event data, a count rate mapping CRMI representing the number of gamma rays counted per unit time in each of the multiple PET detector rings is generated. In the display information DI, the count rate mapping CRMI is overlaid onto the ring display object representing each of the multiple PET detector rings and displayed on the display 74.

[0110] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) of the first application example of the first embodiment, the count rate can be measured in real time based on the simultaneous counting events in each channel of the gamma ray detector 17 during PET imaging data acquisition, and the measured count rate and display information DI are displayed on the display 74 in real time. Therefore, according to this application example, the user can monitor (confirm) the accumulation of radionuclides or the dynamic distribution of radionuclides in the subject P in real time.

[0111] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the first application example of the first embodiment, the user can, for example, select the imaging range of PET imaging based on the count rate, and thus can enter the formal scan (PET scan) of PET imaging with accurate selection of the imaging range and a high dose. That is, according to this application example, a PET scan can be performed without CTscout, thus reducing radiation to the subject P. Moreover, according to this application example, the count rate can be displayed in real time, thus shortening the time of PET examination using FDG (fluorodeoxyglucose) as a radionuclide, i.e., shortening (improving) the examination workflow. Therefore, according to this application example, the dosage of radionuclide administered to the subject P can be reduced, thus reducing radiation to the subject P.

[0112] (Application Example 2)

[0113] In this application example, during information generation and display processing, PET imaging (first scan) is performed in a state (first mode) where multiple PET detector rings 101 are evenly arranged at predetermined intervals corresponding to the body length of the subject P. An accumulation map representing the accumulation distribution of gamma ray counts is generated for each PET detector ring. Next, in this application example, multiple PET detector rings 101 are densely arranged with the position of the PET detector ring corresponding to the accumulation map with the least accumulation among the multiple accumulation distributions corresponding to the multiple PET detector rings 101 as the center. This is the recommended configuration of the multiple PET detector rings 101 in the second scan, and it is displayed on the display 74 in the display information DI.

[0114] The processing circuit 73 performs a first scan (PET scan) on the subject P in a first mode via the camera control function 733. During the first scan, the processing circuit 73 acquires simultaneous count event data based on the outputs of multiple PET detectors mounted on each of the multiple PET detector rings via the acquisition function 734.

[0115] Processing circuit 73, through generation function 735, generates an accumulation map representing the distribution of gamma ray count accumulation per PET detector ring in a plurality of PET detector rings, based on simultaneous counting event data. For example, the accumulation map is dynamically generated during the first scan. The accumulation map is equivalent to a mapping representing the total number of count values ​​for each PET detector per PET detector ring from the start of the first scan up to the current time.

[0116] The processing circuit 73, through the display control function 736, overlays multiple accumulation maps onto the corresponding ring display objects in the display information DI and displays them on the display 74. After the first scan is completed, the display control function 736 determines the accumulation map with the least accumulation among the multiple accumulation maps in the display information DI. The display control function 736 then densely configures multiple PET detector rings 101 with the position of the PET detector ring corresponding to the determined accumulation map as the center (hereinafter referred to as the dense configuration state), and displays it on the display 74 as the recommended configuration of multiple PET detector rings 101 in the second scan that can be performed after the first scan.

[0117] If the dense configuration state related to the second scan is agreed upon by the user through the input interface 76, the processing circuit 73 controls the ring movement mechanism 16 through the movement control function 737 to place the multiple PET detector rings 101 in the dense configuration state.

[0118] In the first scan of the second application example of the first embodiment described above, the PET-CT device 1 (or PET device) acquires simultaneous count event data based on the outputs of multiple PET detectors mounted on each of the multiple PET detector rings in the first mode. Based on the simultaneous count event data, an accumulation map is generated for each of the multiple PET detector rings. In the display information, the dense configuration state is displayed on the display 74 as the recommended configuration of the multiple PET detector rings 101 in the second scan.

[0119] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) of the second application example according to the first embodiment, when uniformly acquiring whole-body PET images of the subject P, simultaneous counting event data can be acquired efficiently. Therefore, according to this application example, the workflow of PET examination for the subject P can be improved, and the examination efficiency (throughput) can be increased.

[0120] (Application Example 3)

[0121] In this application example, during information generation and display processing, the count rate in the count rate mapping RDO reaches a predetermined value as a trigger, causing the switching object, indicating a switch from the first scan (e.g., PET scout) to the corresponding second scan (e.g., PET formal scan), to be displayed, for example, on a display 74 disposed on the surface of the PET gantry 10 and / or the CT gantry 30. The generation of the count rate mapping RDO is the same as in the first application example, therefore detailed description is omitted. The count rate mapping RDO is displayed on this display 74 during both the implementation of the first scan and the implementation of the second scan.

[0122] The memory 75 stores the prescribed values. These prescribed values ​​can be appropriately set or changed by the user through the input interface 76. Additionally, the prescribed values ​​can be set according to the category of the radionuclide.

[0123] The processing circuit 73 determines, through the display control function 736, whether the count count in the count rate mapping RDO has reached a predetermined value. Alternatively, this determination can be achieved through other functions within the processing circuit 73 or through a newly configured determination function. The processing circuit 73, which implements the determination function, is equivalent to a determination unit. The display control function 736, triggering the determination of the count count to reach the predetermined value, displays the switching target on the display 74. The switching target is information used to prompt (propose) the user to switch from PET scout to formal PET scanning, such as character messages like "Perform formal scan?" and / or a button display indicating "Start formal scan".

[0124] If a user inputs a scan mode switch via input interface 76, processing circuit 73, through movement control function 737, controls ring movement mechanism 16 to move multiple PET detector rings 101 along the central axis in order to switch from the first mode under the first scan to the second mode corresponding to the area of ​​the subject P to be imaged. Thus, the configuration of the multiple PET detector rings 101 changes from the first mode to the second mode. Next, processing circuit 73 performs a second scan on subject P through imaging control function 733.

[0125] In the third application example of the first embodiment described above, the PET-CT apparatus 1 (or PET apparatus) displays display information DI with a count rate mapping RDO on a display 74 disposed on the surface of the PET gantry 10 and / or the CT gantry 30. Thus, the user can confirm the count rate in the first scan, just as in the first application example. Furthermore, in this application example, when the count count in the count rate mapping RDO reaches a predetermined value, a switching target is displayed on the display 74. Moreover, in this application example, a formal PET scan is performed on the subject P in accordance with the operation of the switching target.

[0126] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the third application example of the first embodiment, by confirming the real-time count rate mapping (RDO) by the user, the user can operate from the PET gantry 10 and / or the CT gantry 30 to switch the scan mode from the first scan to a formal PET scan (second scan) that performs formal acquisition of simultaneous count event data. Therefore, according to this application example, for example, when rubidium 82 ( 82 In the case of short-half-lived nuclides such as Rb, the dynamic distribution of short-half-lived nuclides in real time (count rate mapping RDO) and the reliable administration of short-half-lived nuclides to the subject P can be easily confirmed. Furthermore, according to this application example, imaging can begin in real time from the confirmation of administration of short-half-lived nuclides to the subject P. As described above, according to this application example, failures in performing formal PET scans on the subject P can be reduced, and the scan switching time can be shortened compared to the past. Therefore, the workflow for PET examination of the subject P is improved, and examination efficiency (throughput) can be increased.

[0127] (Application Example 4)

[0128] In the fourth application example, during a PET scan of a subject P, a first scan is performed with the arrangement of multiple PET detector rings 101 in the first mode. After the first scan is performed, the multiple PET detector rings 101 or the top plate 53 on which the subject P is placed is moved along the central axis so that the multiple PET detector rings 101 are respectively arranged at multiple positions corresponding to the specified intervals in the first mode, and then a second scan is performed.

[0129] During the first scan of the subject P, the processing circuit 73, through the movement control function 737, moves multiple PET detector rings 101 along the central axis so that the multiple PET detector rings 101 are evenly arranged at predetermined intervals corresponding to the body length of the subject P. That is, the movement control function 737 controls the ring movement mechanism 16 to achieve the arrangement of the multiple PET detector rings 101 in the first mode. Thus, the arrangement of the multiple PET detector rings 101 corresponding to the first mode is achieved before the first scan is performed.

[0130] After performing the first scan, the processing circuit 73, through the movement control function 737, moves the plurality of PET detector rings 101 or the top plate 53 carrying the subject P along the central axis, so that the plurality of PET detector rings 101 are respectively positioned at a plurality of positions corresponding to a predetermined interval in the first mode. Specifically, the movement control function 737 controls the ring movement mechanism 16 or the examination bed drive device 54 to position the PET detector rings between two adjacent PET detector rings spaced apart by a predetermined interval in the first mode.

[0131] The processing circuit 73, through the display control function 736, displays the configuration of the plurality of PET detector rings 101 in the first scan and the second scan performed after the first scan as display information DI on the display 74. Specifically, the display control function 736 displays the display information DI on the display 74 in a manner that differs between the relative positional relationship of the plurality of PET detector rings 101 and the top plate 53 during the execution of the first scan and during the execution of the second scan. That is, the display control function 736 displays the display information DI on the display 74 in a manner that alternates between the plurality of ring display objects representing the respective configurations of the plurality of PET detector rings 101 during the execution of the first scan and the plurality of ring display objects representing the respective configurations of the plurality of PET detector rings 101 during the execution of the second scan, relative to the scout image.

[0132] Figure 9 This is a diagram illustrating an example of the difference between the first scan S1 and the second scan S2 in a configuration of multiple PET detector rings 101 relative to the subject P. Figure 9 In the same housing (PET / CT gantry) PCG, PET gantry 10 and CT gantry 30 are shown. Figure 9 As shown, in the first scan S1, multiple PET detector rings 101 are equally arranged at predetermined intervals PI to capture a full-body image of the subject P. Furthermore, as... Figure 9 As shown, in the second scan S2, multiple PET detector rings 101 are respectively arranged at multiple positions at predetermined intervals PI to capture whole-body images of the subject P. Furthermore, the display control function 736 can also display the object RDO using the multiple rings before performing the first scan and before performing the second scan. Figure 9 The display information DI of multiple PET detector rings 101 shown on the scout image of the subject P is displayed on the display 74.

[0133] In the PET-CT apparatus 1 (or PET apparatus) described above in the fourth application example of the first embodiment, during the first scan, multiple PET detector rings 101 are moved along the central axis direction to achieve a first mode. After the first scan, the multiple PET detector rings 101 or the top plate 53 are moved along the central axis direction so that the multiple PET detector rings 101 are respectively arranged at multiple positions corresponding to a predetermined interval in the first mode. During the first and second scans, as follows... Figure 9 The different relative positions of the multiple PET detector rings 101 and the top plate 53 shown enable the display information DI to be displayed on the display 74.

[0134] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the fourth application example of the first embodiment, when a PET scan is performed with multiple PET detector rings 101 uniformly arranged relative to the whole body of the subject P in the first scan, the position of the multiple PET detector rings 101 or the top plate 53 can be adjusted between the first and second scans to fill the gap PI between two adjacent PET detector rings in the arrangement of the multiple PET detector rings 101 in the first scan in the second scan. Therefore, according to this application example, high-sensitivity imaging can be performed on a large imaging range such as the whole body of the subject P. As described above, according to this application example, when obtaining high-sensitivity whole-body images, PET event data can be acquired efficiently, and the workflow of PET examination of the subject P can be improved.

[0135] (Modified Example)

[0136] This variation does not use scout images as information related to the subject P. That is, in this variation, location information and information related to the subject P are obtained based on image data generated by photography through the acquisition function 734. For example, the camera is located outside the PET stand 10 and / or the CT stand 30. Moreover, information related to the subject P is also obtained based on the image data through the acquisition function 734.

[0137] Each of the multiple PET detector rings has a light emitter capable of projecting light perpendicularly to the top plate 53. In each of the multiple PET detector rings, the light emitter is, for example, mounted in a position opposite to the top plate 53. The light emitter projects laser light toward the top plate 53 in a manner perpendicular to it, i.e., parallel to the vertical direction. Furthermore, the light emitter is not limited to a device that projects laser light. For example, if the camera is an optical camera, visible light can also be generated. Additionally, if the camera is an infrared camera, the light emitter can also generate infrared light. Furthermore, the projection of the light emitter can be controlled, for example, by instructions given by a user via the input interface 76, to turn the light emitter on / off.

[0138] The processing circuit 73 acquires, via the acquisition function 734, the projection positions of the light emitted vertically from the multiple light emitters mounted on the multiple PET detector rings 101 towards the top plate 53 on which the subject P is mounted, as position information. For example, the acquisition function 734 determines the projection position in the image data output from the camera through image processing and acquires the determined projection position as position information. Additionally, the acquisition function 734 determines the area of ​​the subject P on the top plate 53 through image processing of the image data and acquires the determined area of ​​the subject P as information related to the subject. Furthermore, image processing can also be performed on the image data output from the camera via the image processing function 732. The image processing for determining the projection position can be suitably performed using existing technology, therefore its description is omitted.

[0139] Figure 10 This is a diagram illustrating an example of the projection position IP of a laser beam projected from a light emitter FL. (See diagram for example.) Figure 10 As shown, multiple PET detector rings 101 are arranged at equal intervals corresponding to the body length of the subject P (Mode 1). Figure 10 As shown, if lasers projected from multiple light emitters FL parallel to the vertical direction toward the top plate 53 reach the top plate 53, they will reach multiple projection positions IP corresponding to the multiple PET detector rings 101 on the top plate 53. Additionally, as... Figure 10 As shown, a first camera 121 is installed on the exterior of the PET stand 10, for example, on a beam extending from the support column PR and mounted on the floor FLO of the examination room. Additionally, a second camera 123 is also installed, for example, above the opening 20 in the CT stand 30. The location of the cameras in this variation is not limited to... Figure 10 As long as multiple projection positions (IPs) can be photographed, the settings can be arbitrary. In this variant, the image data output from the camera is transmitted to the control console 70 via wired or wireless means. At this time, the image data is stored in the memory 75.

[0140] Figure 11This is a diagram illustrating an example of the imaging area IR1 of the first camera 121 and the imaging area IR2 of the second camera 123. For example... Figure 11 As shown, multiple projection positions IP can be photographed by the first camera 121 and the second camera 123. The processing circuit 73 obtains the relative positions of multiple PET detector rings 101 with respect to the top plate 53 based on the multiple projection positions IP in the image data output from the first camera 121 and the second camera 123 through the acquisition function 734, as position information.

[0141] The PET-CT apparatus 1 (or PET apparatus) described above, in its variation of the first embodiment, obtains the projection position IP of the light emitted vertically from the multiple light emitters FL mounted on the multiple PET detector rings 101 to the top plate 53, as position information. Therefore, according to this variation, the subject P within the PET frame 10 and the projection position IP to which the laser is projected are photographed using the first camera 121 outside the PET frame 10 and the second camera 123 mounted inside the CT frame 30. Next, according to this variation, by performing image processing on the photographed images, the position of the subject P and the positions of the multiple PET detector rings 101 can be confirmed in real-time and in a realistic manner.

[0142] Therefore, according to the PET-CT apparatus 1 (or PET apparatus) according to the modification of the first embodiment, without performing scout imaging for obtaining scout images, it is possible to obtain position information of multiple PET detector rings 101 and information related to the subject. Furthermore, according to this modification, by using the method described in the first embodiment… Figure 5 and Figure 6 The document describes a function that pre-configures multiple PET detector rings 101 with imaging modes corresponding to the imaging range selected by the user. Figure 5 , Figure 6 Combined with this variant, multiple PET detector rings 101 can be proposed to the user for the desired imaging range without performing scout imaging of the subject P.

[0143] Therefore, according to this modification, radiation associated with acquiring scout images can be reduced. Furthermore, according to this modification, the effort required for the user to select the imaging range can be reduced, thus improving the efficiency of the workflow for examining the subject P and increasing examination efficiency (throughput).

[0144] (Second Implementation)

[0145] In the second embodiment, the PET detectors are moved out of the X-ray radiation range before CT imaging is performed. For example, the processing circuit 73 controls the ring movement mechanism 16 before CT imaging is performed via the movement control function 737, so that the multiple PET detector rings 101 are moved out of the X-ray radiation range.

[0146] Figure 12 This is a flowchart illustrating an example of the operation of multiple PET detector rings 101 during a PET-CT examination. Figure 12 The image shows an example where a CT scan was performed before a PET scan. However, a CT scan can also be performed after a PET scan. Figure 12 As shown, the user inputs the selection of PET-CT scan, i.e. the execution instruction of CT scan, into the input interface 76 (S121).

[0147] Processing circuit 73, through movement control function 737, controls ring movement mechanism 16 based on the input of CT scan execution instruction, to cause multiple PET detector rings 101 to retract from the radiation range of the CT scan. As a result, the multiple PET detector rings 101 move to a position separated from the CT gantry 30 (S122). At this time, processing circuit 73 can also display the retraction of the multiple PET detector rings 101 out of the X-ray radiation range as display information DI on display 74 through display control function 736.

[0148] If multiple PET detector rings 101 are retracted outside the X-ray radiation range, the processing circuit 73 performs a CT scan on the subject P via the camera control function 733 (S123). Furthermore, the camera control function 733 can also perform a CT scan on the subject P before performing the CT scan.

[0149] Figure 13 This diagram illustrates an example of the positions of multiple PET detector rings 101 that are positioned outside the radiation range of X-rays. (See diagram for example.) Figure 13 As shown, when X-ray irradiation is performed on the subject P, multiple PET detector rings 101 are located outside the X-ray irradiation range. For example, Figure 13 The diagram shown can also be displayed on the display 74 as display information DI in processing S122 via display control function 736.

[0150] After a CT scan is performed on the subject P, the processing circuit 73 controls the ring movement mechanism 16 via the movement control function 737, so that the multiple PET detector rings 101 are evenly arranged in the PET stand 10 along the long axis of the top plate 53, corresponding to the body length of the subject P (S124). Thus, the arrangement of the multiple PET detector rings 101 corresponding to the first mode is completed.

[0151] After configuring the multiple PET detector rings 101 corresponding to the first mode, the position of the PET detector rings is operated on the monitor (display 74) (S125). Next, the position of the PET detector rings is determined (S126). Next, the movement of the PET detector rings is performed (S127). The processing of S125 to S127 is the same as the information generation and display processing IGDP in the first embodiment, so the description is omitted. After the PET detector ring movement is completed, the processing circuit 73 performs a PET scan on the subject through the camera control function 733 (S128).

[0152] The PET-CT apparatus 1 described in the second embodiment above uses the input of an instruction to perform a CT scan on the subject P as a trigger to move multiple PET detector rings 101 away from the imaging range of the CT scan. That is, according to the PET-CT apparatus 1 of the second embodiment, after the user selects a CT scan and before X-ray radiation, the multiple PET detector rings 101 can be moved to a position separated from the radiation range of the CT scan, which can reduce the aging of the gamma ray detector 17 caused by scattered X-rays during CT imaging. Therefore, the PET-CT apparatus 1 according to this embodiment can improve the lifespan of the PET-CT apparatus 1 and reduce maintenance costs and other expenses.

[0153] In implementing the technical concept of this embodiment using an information generation and display method, the method acquires position information in the central axis direction of each of a plurality of PET detector rings that can move relative to the top plate 53 along the central axis direction within the hole 20 into which the top plate 53 for placing the test subject P is inserted. Based on the acquired position information, it generates display information DI related to the position of the plurality of PET detector rings 101 and displays the generated display information DI on the display 74. The processing steps and effects in this information generation and display method are the same as in the first embodiment, and therefore are omitted from the description.

[0154] In implementing the technical concept of this embodiment using an information generation and display program, the program enables a computer to: acquire position information in the central axis direction of each of a plurality of PET detector rings that can move relative to the top plate 53 along the central axis direction within the hole 20 into which the test subject P is inserted; generate display information DI related to the position of the plurality of PET detector rings 101 based on the acquired position information; and display the generated display information DI on the display 74. At this time, the program enabling the computer to execute this method can also be stored in and distributed on storage media such as disks (hard disks, etc.), optical discs (CD-ROMs, DVDs, etc.), and semiconductor memories. Since the processing procedures and effects in the information generation and display program are the same as in the first embodiment, their description is omitted.

[0155] According to at least one embodiment described above, efficiency related to the movement of the positions of the plurality of PET detector rings 101 can be improved.

[0156] The above description illustrates specific embodiments, but these embodiments are merely illustrative and are not intended to limit the scope of the invention. The novel embodiments described above can be implemented in various other ways, and various omissions, substitutions, and modifications can be made to the described embodiments without departing from the spirit of the invention. The appended claims and their equivalents are intended to cover these ways or modifications, all of which are included within the scope and spirit of the invention.

Claims

1. A PET apparatus wherein, have: Multiple PET detector rings are capable of moving relative to the top plate along the central axis direction within the hole into which the top plate for placing the test subject is inserted; The acquisition unit acquires position information along the central axis for each of the plurality of PET detector rings. The generation unit generates display information related to the position of each of the plurality of PET detector rings based on the obtained position information; as well as The display control unit causes the display information to be displayed on the monitor. In the first scan, with the plurality of PET detector rings evenly arranged at predetermined intervals corresponding to the body length of the subject, the acquisition unit acquires simultaneous counting event data based on the outputs from the plurality of PET detectors mounted on each of the plurality of PET detector rings. The generation unit generates an accumulation map representing the distribution of gamma ray count accumulation based on the simultaneous counting event data, for each of the plurality of PET detector rings. The display control unit displays the state of the plurality of PET detector rings densely arranged around the position of the PET detector ring corresponding to the accumulation map with the least accumulation among the plurality of accumulation maps in the display information, as a recommended configuration of the plurality of PET detector rings in the second scan on the display.

2. The PET apparatus as claimed in claim 1, wherein, The acquisition unit also acquires information related to the subject. The generation unit establishes a correspondence between the positions of the plurality of PET detector rings and the information obtained related to the subject to generate the display information.

3. The PET apparatus of claim 1, wherein, It also has: The input unit is used to receive user instructions in the display information to move one or more of the plurality of ring display objects, wherein the plurality of ring display objects respectively represent the plurality of PET detector rings.

4. The PET apparatus as claimed in claim 3, wherein, It also includes a movement control unit, which, after the positions of the plurality of ring display objects are determined, controls one or more PET detector rings corresponding to the one or more ring display objects to move along the central axis direction based on the obtained position information and the determined positions of one or more ring display objects among the plurality of ring display objects. The display control unit updates the display information to reflect the movement of one or more of the plurality of ring display objects along the central axis direction, and displays the updated display information on the display.

5. The PET apparatus of claim 1, wherein, It also has: An input unit is used to input the imaging range of the subject into the displayed information. Based on the imaging range, the generating unit selects an imaging mode close to the imaging range from a plurality of imaging modes, including a first mode and a second mode. The first mode is a mode in which the plurality of PET detector rings are arranged equally at predetermined intervals corresponding to the body length of the subject. The second mode is a mode in which the plurality of PET detector rings are arranged densely along the central axis direction, corresponding to each of the plurality of parts of the subject. In addition to the display information, the display control unit also displays the selected photography mode and the corresponding scan range on the display.

6. The PET apparatus of claim 1, wherein, The acquisition unit acquires the projection position of light vertically projected from the multiple light emitters mounted on the multiple PET detector rings onto the top plate on which the subject is mounted, as the position information.

7. The PET apparatus of claim 1, wherein, The acquisition unit acquires simultaneous count event data based on the outputs of multiple PET detectors mounted on each of the multiple PET detector rings. Based on the simultaneous counting event data, the generation unit generates a count rate map representing the number of gamma rays counted per unit time in each of the plurality of PET detector rings. The display control unit, in the display information, causes the count rate mapping to be superimposed onto the ring display object representing each of the plurality of PET detector rings and displayed on the display.

8. An information generation display method, wherein, Includes the following steps: For each of the multiple PET detector rings that can move relative to the top plate along the central axis direction of the hole into which the top plate for placing the test subject is inserted, position information in the central axis direction is obtained for each of the multiple PET detector rings that can move relative to the top plate along the central axis direction of the hole into which the test subject is inserted. Based on the obtained location information, display information related to the position of each of the plurality of PET detector rings is generated; The display displays the information. In the first scan, with the plurality of PET detector rings arranged equally at predetermined intervals corresponding to the body length of the subject, simultaneous count event data is obtained based on the outputs from the plurality of PET detectors mounted on each of the plurality of PET detector rings. Based on the simultaneous counting event data, an accumulation map representing the distribution of the accumulated gamma ray counts is generated for each of the plurality of PET detector rings; as well as The display information shows that the PET detector rings are densely configured with the position of the PET detector ring corresponding to the accumulation map with the least accumulation among the multiple accumulation maps as the center, and is displayed on the display as the recommended configuration of the multiple PET detector rings in the second scan.

9. A non-volatile storage medium readable by a computer, storing an information generation and display program that enables the computer to perform the following steps: For each of the multiple PET detector rings that can move relative to the top plate along the central axis direction of the hole into which the top plate for placing the test subject is inserted, position information in the central axis direction is obtained for each of the multiple PET detector rings that can move relative to the top plate along the central axis direction of the hole into which the test subject is inserted. Based on the obtained location information, display information related to the position of each of the plurality of PET detector rings is generated; The display displays the information. In the first scan, with the plurality of PET detector rings arranged equally at predetermined intervals corresponding to the body length of the subject, simultaneous count event data is obtained based on the outputs from the plurality of PET detectors mounted on each of the plurality of PET detector rings. Based on the simultaneous counting event data, an accumulation map representing the distribution of the accumulated gamma ray counts is generated for each of the plurality of PET detector rings; as well as The display information shows that the PET detector rings are densely configured with the position of the PET detector ring corresponding to the accumulation map with the least accumulation among the multiple accumulation maps as the center, and is displayed on the display as the recommended configuration of the multiple PET detector rings in the second scan.

Images