Medical imaging diagnostic apparatus, medical imaging diagnostic method, and medical imaging diagnostic program

Abstract

To correctly align a plurality of medical images acquired by a plurality of medical diagnostic apparatuses.SOLUTION: A medical image diagnostic apparatus according to an embodiment comprises: a first medical image diagnostic device which captures a first medical image; a second medical image diagnostic device which captures a second medical image; a marker part; a sensor part; and a calibration part. The marker part is provided in at least one of the first medical image diagnostic device and the second medical image diagnostic device and includes at least one marker. The sensor part is provided in the other of the first medical image diagnostic device and the second medical image diagnostic device and includes at least one sensor for detecting the marker part. The calibration part calibrates position information between the first medical image and the second medical image on the basis of a physical relation between the marker part and the sensor part.SELECTED DRAWING: Figure 3A

Description

Technical Field

[0001] The embodiments disclosed in this specification and the drawings relate to a medical imaging apparatus, a medical imaging method, and a medical imaging program.

Background Art

[0002] In known combined PET / CT scanner systems, since PET (Positron Emission computed Tomography) and CT (Computed Tomography) images are generated by medical diagnostic apparatuses (e.g., scanners) that are spatially separated, even when the combined system uses a single patient transport mechanism that moves between scanners, respective medical images taken at spatially separated locations are generated. In order to "fuse (overlay)" the respective images using such a combined system, it is possible to convert the respective images into a common reference frame using alignment / calibration information. This fused image (e.g., a CT / PET image) may be useful for medical experts to understand the information acquired by the scanner more effectively than using the respective images individually.

[0003] By knowing the relative and / or absolute positions of components (such as a patient transport mechanism and a medical imaging device) in an imaging system, it becomes possible to create a more effectively fused image. One method therefor requires calibration between various components. When attempting to perform these calibrations and maintain the components in a calibrated state, many problems occur. For example, even when a minor maintenance operation is performed, often valuable scanner operation time is used for recalibration. One such realignment often occurs when an offset is formed or changed during the process of separating and then returning the gantry. In such a realignment, calibration can be saved (i.e., pre-saved) for future use until the gantry is separated again.

[0004] In cases where a heavy patient is held by a cantilever-type patient transfer mechanism during imaging, for example, dynamic calibration may be required instead of pre-stored calibration. Since the bed moves between the gantries, an offset occurs due to the deflection of the bed. This offset may not be fully captured by a single pre-stored calibration provided using a single phantom (similar bed deflection would not occur during calibration).

[0005] Furthermore, some known calibrations cannot be performed in the dark, even if some functional imaging requires darkness. In the implementation of the present invention using visible light, some functional imaging (such as measuring responses to visual stimuli in PET or MRI (Magnetic Resonance Imaging)) may be interfered with. In these cases, the present invention could be implemented using a camera (optical sensor) that images invisible radiation such as infrared rays.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to accurately align a plurality of medical images acquired by a plurality of medical diagnostic devices. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problems. The problems corresponding to the effects of each configuration shown in the embodiments described later can also be positioned as other problems.

Means for Solving the Problems

[0008] The medical image diagnostic apparatus according to the embodiment includes a first medical image diagnostic apparatus that captures a first medical image, and a second medical image diagnostic apparatus that captures a second medical image, and includes a marker unit, a sensor unit, and a calibration unit. The marker unit is provided in one of the first medical image diagnostic apparatus and the second medical image diagnostic apparatus, and includes at least one marker. The sensor unit is provided in the other of the first medical image diagnostic apparatus and the second medical image diagnostic apparatus, and includes at least one sensor for detecting the marker unit. The calibration unit calibrates the position information between the first medical image and the second medical image based on the positional relationship between the marker unit and the sensor unit.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2A

Figure 2B

Figure 3A

Figure 3B

Figure 3C

Figure 3D

Figure 3E

Figure 4A

Figure 4B

Figure 5

Figure 6A

Figure 6B

Figure 6C

Figure 7

Figure 8A

Figure 8B

DETAILED DESCRIPTION OF THE INVENTION

[0010] To address at least one problem identified in the known art, the present disclosure describes using image processing to address alignment / calibration issues between various components of a medical diagnostic system (e.g., a PET (Positron Emission computed Tomography) / CT (Computed Tomography) imaging system) accessible via a common patient transport mechanism (e.g., a patient bed). The present disclosure uses a PET / CT system to illustrate exemplary embodiments, but other environments such as a PET / MRI (Magnetic Resonance Imaging) scanner system can also benefit from the teachings herein.

[0011] Apparatuses for calibrating the movement and / or position of a patient transport mechanism shared among a plurality of medical diagnostic devices are described. In one exemplary embodiment, the apparatus includes (1) a first set of integrated optical devices including at least one optical marker, (2) a second set of integrated optical devices including at least one optical sensor for detecting the at least one optical marker, and (3) an image processing circuit configured to determine the position of the patient transport mechanism from the position of the at least one optical marker relative to the at least one optical sensor. The positions and the number of components in the first and second sets of integrated optical devices differ in the exemplary embodiments described herein. Generally, at least one component in one of the first and second sets of integrated optical devices is configured to be attached to the patient transport mechanism, and at least one component in the remaining one of the first and second sets of integrated optical devices is configured to be attached to at least one of the first and second medical diagnostic devices.

[0012] In one embodiment, at least one optical sensor is attached to the gantry, at least one optical marker is attached to the patient transport mechanism, and the image processing circuit determines the position and / or orientation of the patient transport mechanism relative to at least one of the at least one optical marker and the at least one optical sensor.

[0013] In another embodiment, one or more cameras are attached to the patient transfer mechanism, and one or more tags are attached to the gantry. The image processing circuit determines the position and orientation of the patient transfer mechanism relative to this tag.

[0014] Additional embodiments may include image processing for measuring deflection of the patient transfer mechanism, optical markers machined into the patient transfer mechanism or gantry during the manufacturing process, multiple camera inputs (e.g., telephoto lens, wide-angle lens, thermal camera) that can be used for signal averaging, tags that generate heat / thermal signatures, and the like.

[0015] This summary section does not identify all embodiments and / or collectively novel aspects of the present disclosure or the claimed invention. Rather, this summary merely provides a preliminary discussion of different embodiments and corresponding novel points. For additional details and / or possible perspectives of the present invention and embodiments, the reader is directed to the detailed description section of the present disclosure and corresponding drawings discussed further below.

[0016] The following disclosure provides many different embodiments or examples for implementing different features of the provided subject matter. For the sake of simplicity of the present disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to be limiting. Further, the present disclosure may repeat reference numerals and / or letters in various examples. This repetition is for the purpose of simplicity and clarity and in itself does not indicate a relationship between the various embodiments and / or configurations being discussed.

[0017] The order of discussion of the different steps described in this specification is presented for clarification. Generally, these steps can be performed in any suitable order. Furthermore, each of the different features, techniques, configurations, etc. in this specification may be discussed at different places in the present disclosure, but it is intended that each concept can be implemented independently of or in combination with each other. Therefore, the present invention can be implemented and considered in many different ways. This disclosure uses PET / CT scans to illustrate various embodiments, but the same technology can be applied to other scenarios such as PET / MRI scans.

[0018] That is, the medical imaging diagnostic apparatus according to this embodiment includes a first medical imaging diagnostic apparatus that captures a first medical image and a second medical imaging diagnostic apparatus that captures a second medical image. For example, the medical imaging diagnostic apparatus is a PET-CT apparatus in which a PET apparatus and an X-ray CT apparatus are integrated, or a PET-MRI apparatus in which a PET apparatus and an MRI apparatus are integrated. That is, the first medical imaging diagnostic apparatus is one of an X-ray CT apparatus and an MRI apparatus, and the second medical imaging diagnostic apparatus is a PET apparatus. Note that the medical imaging diagnostic apparatus is also called a medical imaging diagnostic system. Also, the first medical image is a CT image or an MRI image, and the second medical image is a PET image.

[0019] For example, a PET-CT apparatus includes a gantry of the PET apparatus, a gantry of the CT apparatus, and a patient transfer mechanism (e.g., a bed). For example, when maintenance work of the PET-CT apparatus is performed, at least one of the gantry of the PET apparatus, the gantry of the X-ray CT apparatus, and the patient transfer mechanism may be moved. In such a case, a deviation may occur in the positional relationship among the gantry of the PET apparatus, the gantry of the X-ray CT apparatus, and the patient transfer mechanism. Therefore, in order to calibrate this deviation in the positional relationship, the PET-CT apparatus according to this embodiment has the following configuration. Note that the configuration according to this embodiment is not limited to the PET-CT apparatus, and is widely applicable to an apparatus (imaging system) capable of superimposing and displaying images captured by a plurality of modalities such as a PET-MRI apparatus.

[0020] A typical PET / CT scan requires multiple gantries that are spatially separated. Alignment calibration is performed to transform each image into a common reference frame and fuse the PET and CT images. This fused image is more valuable than the sum of its parts, as shown in Figure 1. An integrated optical device can be used to align the PET and CT images to a common reference frame, where a first set of integrated optical devices (marker section) includes at least one optical marker and a second set of integrated optical devices (sensor section) includes at least one optical sensor. An example of an optical marker is a two-dimensional barcode (e.g., a tag) that encodes specific reference information as shown in Figures 2A and 2B. These tags can be placed on a medical diagnostic device (e.g., a gantry) or a patient transport mechanism (e.g., a patient bed) and detected by one or more optical sensors (e.g., a camera). In such a configuration, an image processing circuit can extract the position, orientation, and identity (characteristics) of each marker. From a single camera, six degrees of freedom (e.g., origin, x = 0, y = 0, z = 0, and the directions of the x, y, and z axes) can be determined with varying accuracy. By using multiple cameras that image the same tag from different viewpoints, the accuracy can be improved. Determining the position of the camera from these tags is very cost-effective, fast, and robust, so alignment calibration can be performed for all scans as needed. This is effectively a dynamic self-calibration alignment scan of two separate medical diagnostic devices that are spatially separated and use a common patient transport mechanism. The example of the binary square reference marker shown in Figure 2B provides a combination of high-contrast features, ID encoding, and a clear orientation determination ability that is very useful for unconstrained measurement problems. In the case described in this disclosure, where the general position of the marker can be known and most movement is restricted to a known range, a wide range of markers can be used as long as they provide sufficient contrast for imaging by the optical sensor.

[0021] Incidentally, the PET / CT scan further includes a control unit (bed control unit) that controls the movement of the patient transfer mechanism (bed). For example, the PET / CT scan includes a bed that supports the bed. The bed control unit is provided on the bed or gantry of the PET / CT scan and moves the bed along the longitudinal direction of the bed. Here, the image processing circuit determines the position of the patient transfer mechanism after movement compared with the initial position (position before movement) of the patient transfer mechanism based on the movement of the patient transfer mechanism. Then, the image processing circuit calibrates the position information based on the determined position after movement.

[0022] That is, the image processing circuit according to the present embodiment is an example of a "calibration unit" that calibrates the position information between the first medical image and the second medical image based on the positional relationship between the marker unit and the sensor unit.

[0023] For example, the calibration unit calibrates the position information based on the absolute positions of the marker unit and the sensor unit respectively. The absolute position is, for example, the coordinates of each marker included in the marker unit and the coordinates of each sensor included in the sensor unit.

[0024] Also, for example, the calibration unit calibrates the position information based on the relative positions of the marker unit and the sensor unit respectively. The relative position is information indicating the distance and direction between each marker included in the marker unit and each sensor included in the sensor unit.

[0025] Using various combinations of optical sensors and optical markers, various calibrations described herein can be performed, monitored, and maintained. For example, a first calibration determines the offset between a first medical diagnostic device and a second medical diagnostic device. During the process of separating and returning the gantries, an offset may occur, which usually requires recalibration. The calibration that determines the offset between these two medical diagnostic devices can also identify the offset and correct it when fusing scan data. Throughout this disclosure, this calibration is referred to as gantry calibration with respect to the gantry. Similarly, a second calibration determines the position and orientation of the patient transport mechanism with respect to each medical diagnostic device, and hereafter, this is referred to as gantry calibration with respect to the bed.

[0026] Note that in this embodiment, "calibration" does not mean moving the position of the gantry or the bed, but rather refers to calibrating (adjusting) the position information (offset) between the first medical image and the second medical image. According to this embodiment, multiple medical images acquired by multiple medical diagnostic devices can be accurately aligned with each other.

[0027] In this first exemplary embodiment, one or more cameras functioning as optical sensors are arranged on the patient transport mechanism, and one or more two-dimensional barcodes functioning as optical markers are arranged on the gantry. One or more markers / tags can be firmly attached to each gantry at different known positions. The geometric design of the scanner is used to determine where to place the markers. The cameras attached to the patient transport mechanism scan these markers throughout the PET / CT imaging process. Figures 3A - 3E show some examples of layouts incorporating this embodiment.

[0028] In FIG. 3A, no patient imaging is being performed. The device configuration is as follows as a pre-scan or default configuration. Camera 301 is attached to patient bed 302, first marker 303 is disposed on first medical diagnostic device 304, and second marker 305 is disposed on second medical diagnostic device 306. Patient transport mechanism 302 has not yet entered first medical diagnostic device 304. In this embodiment, first medical diagnostic device 304 is shown as a CT gantry, and second medical diagnostic device 306 is shown as a PET gantry. However, note that the scan order of the gantries is not important. In other words, the first medical diagnostic device could be a PET gantry, an MRI gantry, etc. in other embodiments.

[0029] Calibration of the gantry with respect to the gantry can be performed at any time as long as the images are within the layout shown in FIG. 3A and before they are fused. As long as camera 301 has a field of view with respect to first marker 303 and second marker 305, position information can be captured. From there, the processing circuit can calculate the gantry offset. If the gantry offset is not the default (i.e., the last calculated offset), an alert or error message may be triggered. Additionally or alternatively, the patient scan can be performed with this new gantry offset, and the image processing circuit can take this new offset into account when fusing the PET image and the CT image.

[0030] In FIG. 3B, the patient bed 302 has entered the first medical imaging device 304. The calibration of the gantry with respect to the bed of the first gantry 304 can be performed here, and the camera 301 captures the position data of the first marker 303 with respect to itself for the processing circuit to process. The machine learning software enables the camera 301 to recognize the first marker 303 on the first gantry 304 and the second marker 305 on the second gantry 306, and the image processing circuit uses the data received by the combination of the camera and the markers to determine the position and orientation of each optical marker. All the captured results (e.g., the distance from the marker to the camera, the angle from the marker to the camera, the rotation direction from the gantry to the camera, etc.) are processed by the processing circuit so that they can be fused after all imaging has occurred.

[0031] In FIG. 3C, the end of the patient bed 302 is located between the first gantry 304 and the second gantry 306. Even if the camera 301 has passed through the first gantry 304, if the camera 301 has visibility with respect to the first marker 303 on the first gantry 304, the patient image taken from the first gantry 304 can be calibrated and fused by the processing circuit. If all the necessary imaging and position information from the first gantry 304 has already been captured, a line of sight is desirable but not absolutely necessary.

[0032] In FIG. 3D, the patient bed 302 has entered the second medical imaging device 306. The calibration of the gantry with respect to the bed for the second gantry 306 can be performed here before the patient scan is carried out, the camera 301 can capture an image of the marker 305, and the processing circuit can extract the marker 305 position data.

[0033] In FIG. 3E, the camera 301 has passed both gantries. The patient's image can be taken in this layout. As long as the camera 301 can visually recognize the marker 303 on the first gantry 304 and similarly the marker 305 on the second gantry 306, calibration / integration can be monitored at each gantry. When the patient's scan is completed, both the patient's scan data and the PET / CT alignment data are generated.

[0034] That is, the marker part is attached to the gantry of the first medical imaging diagnostic apparatus and the gantry of the second medical imaging diagnostic apparatus. The sensor part is attached to the patient transport mechanism provided in the medical imaging diagnostic apparatus.

[0035] In some examples, the markers may rotate relative to each other. For example, FIG. 4A shows a first marker 403 disposed on a CT gantry 404 and a second marker 405 disposed on a PET gantry 406. FIG. 4B shows a perspective view looking down on the markers from the viewpoint of the camera 401, and the second marker 405 on the PET gantry 406 is slightly rotated with respect to the first marker 403 on the CT gantry 404. Since the orientations of the respective markers can be extracted even if they rotate relative to each other, the image processing circuit will be able to correct the captured image and properly align it.

[0036] Additional tags or cameras can be placed to perform further calibration as needed. There are ways to identify, calibrate, and account for detector elements that are disrupted or defective (e.g., improperly manufactured). For example, as shown in FIG. 5, a useful calibration can be the alignment of critical detector elements. In the case of the CT gantry 501, the critical alignment elements are the X-ray tube 502 and the CT detector 503. In the case of the PET gantry 504, the critical alignment element is the PET detector 505. Additional optical markers 506 can be placed on these critical elements to determine their relative positions with respect to each other or with respect to any other optical device 507 before scanning. Optionally, any of the markers can be hidden (e.g., by placing a cover over the marker) and visualized only when needed.

[0037] The various calibrations described can be performed every time for each scan or can be performed based on pick-and-choose. For example, the calibration of the gantry with respect to the gantry can be performed every time the gantry is moved and every time the cover is opened and closed during all routine clinical scans. In the above description, the calibration is performed once for each imaging system. In other cases such as helical CT scans or continuous bed movement PET, the calibration can be performed at multiple individual time points, and then the calibration can be determined at any time by interpolation. In the case of step-and-shoot PET acquisition, an individual calibration can be determined for each bed position.

[0038] Figures 6A - 6C are useful for explaining another embodiment, where one or more optical markers are placed on the patient transport mechanism and one or more sensors are placed on the medical imaging device.

[0039] In FIG. 6A, the marker / tag 602 is disposed on the patient bed 601, the first camera 604 is disposed on the CT gantry 603, and the second camera 606 is disposed on the PET gantry 605. The patient bed has not yet entered any of the gantries. For example, the pre-scan settings as default settings are as follows. However, calibration / integration can still be performed (e.g., gantry calibration for the gantry, gantry calibration for the bed). In this configuration, clinical scans may or may not be performed. Again, this is because the optical calibration system and the normal functions of the scanner operate independently.

[0040] In FIG. 6B, the marker 602 has passed through the CT gantry 603. While the CT scan of the patient is being captured, the first camera 604 captures the position data of the marker 602 for the calibration of the gantry with respect to the bed. The data captured from this calibration of the gantry with respect to the bed is transmitted to the processing circuit.

[0041] In FIG. 6C, the marker 602 passes through the PET gantry 605 and the PET image of the patient is being captured. The CT image of the first gantry 603 can also be captured during this time. While the PET scan of the patient is being captured, the camera 606 on the second gantry 605 captures the position data from the marker 602. The data captured from this calibration from the gantry to the bed is also sent to the processing circuit.

[0042] That is, the marker unit is attached to the patient transfer mechanism provided in the medical imaging diagnostic apparatus. Also, the sensor unit is attached to the gantry of the first medical imaging diagnostic apparatus and the gantry of the second medical imaging diagnostic apparatus.

[0043] The calibration of the gantry with respect to the bed of each gantry can occur when each respective gantry is imaging the patient, but the calibration of the gantry with respect to the gantry can be performed at any time as long as the images are not yet fused. After both medical imaging devices have scanned the patient, the PET / CT images are fused using the calibration data.

[0044] Additional markers or cameras can be placed to perform additional calibration as needed. For example, as shown in FIG. 7, a marker 701 can be placed on important components such as an X-ray tube 702, a CT detector 703, and a PET detector 704, and the position of a camera 705 relative to these important components, or the position of the camera 705 relative to each other among these important components, can be determined.

[0045] Another embodiment includes image processing for measuring the deflection of a patient transfer mechanism. Since a camera and an optical tag (2D barcode) are used, it is possible to estimate six degrees of freedom [the center of the tag (x, y, z), the normal direction of the tag (two angles), and the rotation about the normal], and using the measured values of the movement and orientation changes of a single tag, the deflection of the cantilever bed can be estimated. One example where these deflections can occur is when there is a heavy patient on the patient bed. The continuous movement of the bed can be evaluated using camera-based spatial positioning. Information on the continuous bed positions (including changes in the magnitude and direction of deflection) is integrated using reconstruction software, where the image processing circuit takes the deflection into account (e.g., the patient transfer mechanism moves during the execution of the scan). For example, during the calibration process before scanning the patient (e.g., loading bags filled with sand of various weights onto the bed to mimic various weights, and measuring the displacements at various points along the bed when the bed is extended), a model or look-up table relating displacement and angle can be determined, which relates the displacement and angle of the tags at the end of the bed to the deflection at various points along the length of the bed. Alternatively, a mechanical finite element model (FEM) can be used to generate a look-up table that can relate the deflection measured at one tag position to the deflection at various points along the length of the bed. One embodiment for use with a cantilever bed is shown in FIGS. 8A and 8B. In this case, as shown in FIG. 8A, a first tag 801, a second tag 802, and a third tag 803 are applied along the longitudinal direction (direction of movement) of the bed 804. As the bed 804 moves, as shown in FIG. 8B, it will have a deflection. Even if the bed is deflected, at any given point in time, by acquiring and processing an image from the camera, the position and orientation of each tag can be determined. Then, the position and orientation of the bed surface at other positions can be estimated by interpolating the measurements from the tag positions.

[0046] In FIGS. 8A and 8B, the marker unit includes at least two markers attached to a patient transfer mechanism included in a medical imaging device. The sensor unit is attached to at least one of the first medical imaging device and the second medical imaging device.

[0047] Note that the positions of the marker unit and the sensor unit may be reversed. That is, the marker unit is attached to at least one of the first medical imaging device and the second medical imaging device. The sensor unit includes at least two sensors attached to a patient transfer mechanism included in a medical imaging device.

[0048] That is, at least two markers or at least two sensors provided in the patient transfer mechanism are arranged along the moving direction of the patient transfer mechanism. The calibration unit measures at least one of the magnitude and direction of the deflection after the movement of the patient transfer mechanism, and calibrates the position information (offset) based on at least one of the measured magnitude and direction of the deflection.

[0049] Another embodiment includes the use of different optical sensors (e.g., telephoto lens, wide-angle lens) at various locations for signal averaging. A plurality of different optical sensors can be attached to each medical imaging device or patient bed. Some optical sensor inputs may be weighted more than other inputs when calculating position and orientation. For example, a camera with a telephoto lens can be weighted more than a wide-angle lens. In another embodiment, a single camera may include a zoom lens that enables acquisition of both wide-angle and telephoto fields of view.

[0050] Furthermore, another embodiment involves using a thermo-optical sensor (e.g., a thermal camera), a thermo-optical marker (e.g., an infrared emission tag), and the thermal signature of the device. The optical sensor can detect, for example, infrared light and / or ultraviolet light. The use of a thermal sensor can be useful when imaging needs to be performed in the dark (such as when performing some types of functional imaging or when the patient is light-sensitive). In this case, the tag can perhaps be made to emit infrared light, for example, by differential heating of separate elements within the tag or by using an infrared light-emitting diode, or the tag can be illuminated by an external infrared light source.

[0051] Another embodiment involves using multiple optical sensors and / or multiple optical markers for redundancy or additional calibration. For example, even if a patient or other equipment (such as an IV holder) blocks one camera or one marker, the system can still function because another camera or marker still has a line of sight.

[0052] In other words, the sensor unit may include a camera that detects visible light. Also, the sensor unit may include a camera that detects at least one of infrared light and ultraviolet light. Also, the marker unit may include a two-dimensional barcode. Also, the marker unit may include an infrared emission tag.

[0053] Another embodiment includes tags that are mechanically processed onto a patient transport mechanism or gantry during the manufacturing process. Processing the tags can be done more quickly and accurately than manually placing the tags. Further, after machining, paint or dye (or a similar substance) can be applied to these tags to improve visibility. For example, the tags may be colored.

[0054] In other words, the marker unit may be mechanically processed onto the patient transport mechanism. Also, the marker unit may be mechanically processed onto the patient transport mechanism during the manufacture of the patient transport mechanism. Also, the marker unit may include an optical marker that is painted after being machined.

[0055] Also, as described above, either the marker unit or the sensor unit may be provided on the gantry and the other may be provided on the bed. That is, the marker unit is provided on one of the first medical imaging diagnostic apparatus and the second medical imaging diagnostic apparatus and includes at least one marker. Further, the sensor unit is provided on the other of the first medical imaging diagnostic apparatus and the second medical imaging diagnostic apparatus and includes at least one sensor for detecting the marker unit. Here, the "other" means the one on which the marker unit is not provided.

[0056] Note that, for example, in order to calibrate the position information between a CT image and a PET image, it is preferable that at least the marker unit is provided on one of the gantry of the X-ray CT apparatus and the gantry of the PET apparatus, and the sensor unit is provided on the other of the gantry of the X-ray CT apparatus and the gantry of the PET apparatus.

[0057] Also, there may be a case where the positional relationship between the gantry of the X-ray CT apparatus and the bed (initial position) is invariant (constant). For example, when only the PET apparatus is moved during maintenance work, the positional relationship between the gantry of the X-ray CT apparatus and the bed is invariant. Further, for example, when the position of the bed is fixed at a predetermined position by an anchor or the like, even if the bed is moved, it can be returned to the original position. Also in this case, the positional relationship between the gantry of the X-ray CT apparatus and the bed is invariant. In such a case, the marker unit may be provided on one of the bed and the gantry of the PET apparatus, and the sensor unit may be provided on the other of the bed and the gantry of the PET apparatus.

[0058] The methods and systems described herein can be implemented in many technologies, but generally relate to processing circuitry for executing the processes described herein. In one embodiment, the processing circuitry (e.g., an image processing circuit and a controller circuit) is implemented as an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Generic Array Of Logic (GAL), a Programmable Array Of Logic (PAL), a circuit that allows one-time programmability of logic gates (e.g., using fuses) or a combination of one or more of reprogrammable logic gates. Further, the processing circuitry can include a computer processor and can have embedded and / or external non-volatile computer-readable memory (e.g., RAM, SRAM, FRAM®, PROM, EPROM, and / or EEPROM) for storing computer instructions (binary executable instructions and / or interpreted computer instructions) for controlling the computer processor to execute the processes described herein. The computer processor circuitry can implement a single processor or multiple processors, each supporting a single thread or multiple threads and each having a single core or multiple cores. In embodiments where a neural network is used, the processing circuitry used to train an artificial neural network need not be the same as the processing circuitry used to implement the trained artificial neural network that performs the calibration described herein. For example, a processor circuit and memory can be used to generate a trained artificial neural network (such as defined by its interconnections and weights), and an FPGA can be used to implement the trained artificial neural network.Furthermore, the training and use of the trained artificial neural network can use serial or parallel implementations (e.g., by implementing the trained neural network on a parallel processor architecture such as a graphics processor architecture) to improve performance.

[0059] In the foregoing description, specific details have been set forth, such as specific methods and systems for calibrating a patient transport mechanism using first and second sets of integrated optical systems, and descriptions of various components and processes used therein. However, it should be understood that the techniques herein can be practiced in other embodiments that depart from these specific details, and that the description of such details is for purposes of explanation and not limitation. The embodiments disclosed herein are described with reference to the accompanying drawings. Similarly, for purposes of explanation, specific numbers, materials, and configurations are shown to provide a complete understanding. However, the embodiments can be practiced without such specific details. Components having substantially the same functional structure can be denoted by like reference characters, and thus redundant description may be omitted.

[0060] For the sake of helping in understanding the various embodiments, various techniques have been described as a plurality of individual operations. The order of description should not be construed to mean that these operations necessarily depend on the order. In fact, these operations need not be performed in the order presented. The described operations can be performed in an order different from the described embodiments. In additional embodiments, various additional operations can be performed and / or the described operations can be omitted.

[0061] Those skilled in the art will also understand that many modifications can be made to the operation of the technology described above while achieving the same object of the present invention. Such modifications are intended to be included within the scope of the present disclosure. Accordingly, the foregoing description of the embodiments of the present invention is not intended to be limiting. Rather, the limitations to the embodiments of the present invention are presented in the following claims.

Explanation of Reference Numerals

[0062] 301 Camera 302 Patient transfer mechanism 303 First marker 304 First medical diagnostic device 305 Second marker 306 Second medical diagnostic device

Claims

A medical imaging diagnostic apparatus comprising: a patient transfer mechanism for transferring a patient; a first gantry of a first medical imaging diagnostic apparatus that captures a first medical image; and a second gantry of a second medical imaging diagnostic apparatus that captures a second medical image, a marker unit including at least one marker, a sensor unit including at least one sensor for detecting the marker unit, a calibration unit that calibrates position information between the first medical image and the second medical image based on a positional relationship between the marker unit and the sensor unit, and comprising, wherein one of the marker and the sensor is provided in the patient transfer mechanism along the moving direction of the patient transfer mechanism in a plurality of numbers, the remaining one of the marker and the sensor is provided on the first gantry and the second gantry, the calibration unit, by determining the position and orientation of each of the plurality of markers arranged in the moving direction, or the position and orientation of each of the plurality of sensors arranged in the moving direction, measures at least one of the magnitude and direction of deflection after the movement of the patient transfer mechanism, and calibrates the position information based on at least one of the measured magnitude and direction of deflection, a medical imaging diagnostic apparatus.

2. The first medical imaging diagnostic apparatus is one of an X-ray CT (Computed Tomography) apparatus and an MRI (Magnetic Resonance Imaging) apparatus, the second medical imaging diagnostic apparatus is a PET (Positron Emission computed Tomography) apparatus, The medical imaging diagnostic apparatus according to claim 1.

3. The medical imaging diagnostic apparatus further comprises a control unit that controls the movement of the patient transfer mechanism provided in the medical imaging diagnostic apparatus, the calibration unit, determines the position after the movement of the patient transfer mechanism compared to the initial position of the patient transfer mechanism based on the movement of the patient transfer mechanism, and calibrates the position information based on the determined position after the movement, The medical imaging diagnostic apparatus according to claim 1 or 2.

4. The calibration unit calibrates the position information based on the absolute positions of the marker unit and the sensor unit respectively, The medical imaging diagnostic apparatus according to any one of claims 1 to 3.

5. The calibration unit calibrates the position information based on the relative positions of the marker unit and the sensor unit respectively, The medical imaging diagnostic apparatus according to any one of claims 1 to 3.

6. The sensor unit includes a camera that detects visible light. The medical image diagnostic apparatus according to any one of claims 1 to 5.

7. The sensor unit includes a camera that detects at least one of infrared rays and ultraviolet rays. The medical image diagnostic apparatus according to any one of claims 1 to 6.

8. The marker unit includes a two-dimensional barcode. The medical image diagnostic apparatus according to any one of claims 1 to 7.

9. The marker unit includes an infrared light-emitting tag. The medical image diagnostic apparatus according to any one of claims 1 to 8.

10. The marker unit is machined on a patient transfer mechanism included in the medical image diagnostic apparatus. The medical image diagnostic apparatus according to any one of claims 1 to 9.

11. The marker unit is machined on the patient transfer mechanism during the manufacture of the patient transfer mechanism included in the medical image diagnostic apparatus. The medical image diagnostic apparatus according to any one of claims 1 to 10.

12. The marker unit includes an optical marker that is painted after the machining. The medical image diagnostic apparatus according to claim 10 or 11.

13. A medical image diagnostic method using a medical image diagnostic apparatus including a patient transfer mechanism for transferring a patient, a first gantry of a first medical image diagnostic apparatus for imaging a first medical image, and a second gantry of a second medical image diagnostic apparatus for imaging a second medical image, calibrating the position information between the first medical image and the second medical image based on a positional relationship between a marker unit including at least one marker and a sensor unit including at least one sensor for detecting the marker unit including One of the marker and the sensor is provided in the patient transfer mechanism along the moving direction of the patient transfer mechanism in a plurality of numbers, The remaining one of the marker and the sensor is provided on the first gantry and the second gantry, The process of calibrating is by determining the position and orientation of each of the plurality of markers arranged in the moving direction, or the position and orientation of each of the plurality of sensors arranged in the moving direction, measuring at least one of the magnitude and direction of deflection after the movement of the patient transfer mechanism, calibrating the position information based on at least one of the measured magnitude of deflection and the direction of deflection, Medical image diagnostic method. A medical image diagnosis program for causing a computer to execute a process using a medical image diagnosis apparatus including a patient transfer mechanism for transferring a patient, a first gantry of a first medical image diagnosis apparatus for capturing a first medical image, and a second gantry of a second medical image diagnosis apparatus for capturing a second medical image, calibrating position information between the first medical image and the second medical image based on a positional relationship between a marker unit including at least one marker and a sensor unit including at least one sensor for detecting the marker unit causing the computer to execute the process, wherein one of the marker and the sensor is provided in the patient transfer mechanism along a moving direction of the patient transfer mechanism in a plurality of numbers, the remaining one of the marker and the sensor is provided in the first gantry and the second gantry, the calibrating process measures at least one of a magnitude and a direction of deflection after movement of the patient transfer mechanism by determining positions and orientations of the plurality of markers arranged in the moving direction or positions and orientations of the plurality of sensors arranged in the moving direction, calibrates the position information based on at least one of the measured magnitude and direction of the deflection, Medical image diagnosis program.

Images