Medical image processing device and medical image processing method

Abstract

To present a quantitative index of collateral blood circulation directly related to treatment determination and prognosis.SOLUTION: A medical image processing device according to an embodiment comprises: an acquisition unit; a generation unit; a first setting unit; a second setting unit; a calculation unit; and an output unit. The acquisition unit acquires medical images in plural time phases about an object tissue of a subject. The generation unit generates a blood vessel domination region image expressing a plurality of blood vessel domination regions included in the object tissue on the basis of the medical images in plural time phases. The first setting unit sets a region of interest in the object tissue. The second setting unit sets at least two regions in the plurality of blood vessel domination regions and an ischemic region in the region of interest on the basis of the blood vessel domination region image. The calculation unit calculates a ratio about each of the at least two regions and the region of interest. The output unit outputs information about the ratio.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The embodiments disclosed in this specification and the drawings relate to a medical image processing device and a medical image processing method. [Background technology]

[0002] Conventionally, medical image processing devices are used to diagnose infarction in target tissues such as the brain. For patients with infarction, the presence of collateral circulation is important because it is an indicator of the possibility of tissue recovery. Here, collateral circulation refers to new circulatory vessels that develop when stenosis or occlusion occurs to compensate for the deterioration of blood flow. Therefore, quantitative evaluation of collateral circulation at the tissue level, which is directly related to treatment decisions and prognosis, is desired. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2013-513411 [Patent Document 2] US Patent Application Publication No. 2015 / 0125058 [Patent Document 3] Japanese Patent Application Laid-Open No. 2015-231411 Summary of the Invention [Problem to be solved by the invention]

[0004] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to provide a quantitative index of collateral circulation that is directly related to treatment decisions and prognosis. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problem. Problems corresponding to the effects of each configuration shown in the embodiments described below can also be positioned as other problems. [Means for solving the problem]

[0005] A medical image processing apparatus according to an embodiment includes an acquisition unit, a generation unit, a first setting unit, a second setting unit, a calculation unit, and an output unit. The acquisition unit acquires medical images of a target tissue of a subject at multiple time phases. The generation unit generates a vascular control region image representing multiple vascular control regions included in the target tissue based on the medical images at multiple time phases. The first setting unit sets a region of interest in the target tissue. The second setting unit sets at least two regions out of the multiple vascular control regions and an ischemic region within the region of interest based on the vascular control region image. The calculation unit calculates a ratio between each of the at least two regions and the region of interest. The output unit outputs information related to the ratio. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a medical image processing apparatus according to the first embodiment. [Figure 2] FIG. 2 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry according to the first embodiment. [Figure 3] FIG. 3 is a flowchart showing the processing procedure of the processing performed by the processing circuit according to the first embodiment. [Figure 4] FIG. 4 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry according to the second embodiment. [Figure 5] FIG. 5 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry according to the third embodiment. [Figure 6] FIG. 6 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry according to the fourth embodiment. [Figure 7] FIG. 7 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry according to the fifth embodiment. [Figure 8] FIG. 8 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry according to the sixth embodiment. [Figure 9]FIG. 9 is a diagram illustrating an example of the configuration of a medical image processing apparatus according to the seventh embodiment. [Figure 10] FIG. 10 is a diagram for explaining an example of processing performed by a determination function of a processing circuit according to the seventh embodiment. [Figure 11] FIG. 11 is a flowchart showing the processing procedure of the processing performed by the processing circuit according to the seventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments of a medical image processing apparatus and a medical image processing method will be described in detail with reference to the drawings.

[0008] (First embodiment) FIG. 1 is a diagram illustrating an example of the configuration of a medical image processing apparatus according to the first embodiment.

[0009] For example, as shown in FIG. 1, a medical image processing apparatus 100 according to this embodiment is connected to a medical image diagnostic apparatus 20 and a medical image storage apparatus 30 via a network 10 so that they can communicate with each other.

[0010] The medical image diagnostic device 20 acquires medical images of a subject (such as a patient) to be used for image diagnosis, etc. Specifically, the medical image diagnostic device 20 generates two-dimensional images or three-dimensional images (also called volume data) of the subject as medical images. For example, the medical image diagnostic device 20 is an X-ray CT (Computed Tomography) device, an MRI (Magnetic Resonance Imaging) device, or the like.

[0011] The medical image storage device 30 acquires medical images from the medical image diagnostic device 20 via the network 10 and stores the acquired medical images in a memory circuit within the device. For example, the medical image storage device 30 is realized by a computer device such as a server or a workstation.

[0012] The medical image processing device 100 acquires medical images from a medical image diagnostic device 20 or a medical image storage device 30 via a network 10, and performs various processes using the acquired medical images. For example, the medical image processing device 100 is realized by computer equipment such as a server, a workstation, a personal computer, or a tablet terminal.

[0013] Specifically, the medical image processing apparatus 100 includes a network (NW) interface 110, a storage circuitry 120, an input interface 130, a display 140, and a processing circuitry 150.

[0014] The NW interface 110 controls the transmission and communication of various data sent and received between the medical image processing device 100 and other devices connected via the network 10. Specifically, the NW interface 110 is connected to the processing circuitry 150, and outputs medical images received from the medical image diagnostic device 20 or the medical image storage device 30 to the processing circuitry 150. For example, the NW interface 110 is realized by a network card, a network adapter, a NIC (Network Interface Controller), or the like.

[0015] The memory circuitry 120 stores various data, various programs, etc. Specifically, the memory circuitry 120 is connected to the processing circuitry 150, and stores input medical images or outputs stored medical images to the processing circuitry 150 in response to commands sent from the processing circuitry 150. For example, the memory circuitry 120 is realized by a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, a hard disk, an optical disk, etc.

[0016] The input interface 130 accepts input operations of various instructions and information from an operator. Specifically, the input interface 130 is connected to the processing circuit 150, converts the input operations received from the operator into electrical signals, and outputs the electrical signals to the processing circuit 150. For example, the input interface 130 may be realized by a trackball, a switch button, a mouse, a keyboard, a touchpad that performs input operations by touching the operation surface, a touchscreen that integrates a display screen and a touchpad, a non-contact input interface using an optical sensor, a voice input interface, or the like. Note that, in this specification, the input interface 130 is not limited to those that include physical operation components such as a mouse and a keyboard. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs the electrical signal to a control circuit is also included as an example of the input interface 130.

[0017] The display 140 displays various types of information and various types of data. Specifically, the display 140 is connected to the processing circuit 150 and displays various types of information and various types of data output from the processing circuit 150. For example, the display 140 is realized by a liquid crystal monitor, a CRT (Cathode Ray Tube) monitor, a touch panel, or the like.

[0018] The processing circuitry 150 controls the components of the medical image processing apparatus 100 in response to input operations received from an operator via the input interface 130. For example, the processing circuitry 150 stores medical images output from the NW interface 110 in the storage circuitry 120. Furthermore, for example, the processing circuitry 150 reads out the medical images from the storage circuitry 120 and displays them on the display 140.

[0019] The above has described the overall configuration of the medical image processing device 100 according to this embodiment. With such a configuration, the medical image processing device 100 according to this embodiment is installed in a medical facility such as a hospital, and is used to diagnose infarction in a target tissue such as the brain.

[0020] In patients with infarction, the presence of collateral blood flow is important because it is an indicator of the potential for tissue recovery. Collateral blood flow refers to new circulatory vessels that develop when a stenosis or occlusion occurs to compensate for the deterioration of blood flow.

[0021] For this reason, a technique for scoring collateral circulation using parameters obtained by perfusion analysis has been proposed. This technique calculates the ratio of the amount of blood flowing into major arteries (e.g., cerebral blood volume) to the amount of blood perfusing into brain tissue (e.g., cerebral blood flow rate) for each of a healthy cerebral hemisphere and a non-healthy cerebral hemisphere (e.g., one with an infarct), thereby making it possible to calculate the proportion of blood supplied by collateral circulation that flows into non-healthy tissue.

[0022] In addition, collateral circulation is known to exist in two types: antegrade and retrograde. Since retrograde collateral circulation has poorer hemodynamics than antegrade collateral circulation, it is also important to distinguish whether the collateral circulation is antegrade or retrograde.

[0023] For this reason, a technology has been proposed that creates a color map representing vascularized regions of the brain based on contrast imaging. Here, vascularized regions refer to regions of an organ containing multiple arteries, divided into regions nourished by each artery. This technology divides brain regions into anatomically defined vascularized regions, but rather divides them using the arrival time of a contrast agent perfused into brain tissue. This makes it possible to create images representing vascularized regions that reflect the presence or absence of infarcted regions and collateral blood flow.

[0024] However, these techniques all evaluate the state of collateral circulation, and it is difficult to quantitatively evaluate collateral circulation at the tissue level, which is directly related to treatment decisions and prognosis.

[0025] For example, the first technique requires blood flow through major arteries to score the amount of collateral circulation, but the medical imaging diagnostic equipment (also called modality) commonly used for diagnosis lacks the time resolution to accurately measure blood flow. Furthermore, for example, the second technique visualizes collateral circulation, but it is difficult to quantitatively determine which blood vessels are dominant within the vascularly-dominated area of ​​an infarct.

[0026] For this reason, the medical image processing apparatus 100 according to this embodiment is configured to be able to present a quantitative index of collateral circulation that is directly related to treatment decisions and prognosis.

[0027] Specifically, the processing circuit 150 has an acquisition function 151, a generation function 152, a first setting function 153, a second setting function 154, a calculation function 155, and an output function 156. Here, the acquisition function 151 is an example of an acquisition unit. The generation function 152 is an example of a generation unit. The first setting function 153 is an example of a first setting unit. The second setting function 154 is an example of a second setting unit. The calculation function 155 is an example of a calculation unit. The output function 156 is an example of an output unit.

[0028] The acquisition function 151 acquires medical images of a plurality of time phases relating to a target tissue of a subject to be diagnosed from the medical image diagnostic device 20 or the medical image storage device 30. The generation function 152 generates a vascular control region image representing a plurality of vascular control regions included in the target tissue of the subject, based on the medical images of the plurality of time phases acquired by the acquisition function 151.

[0029] The first setting function 153 sets a region of interest in a target tissue of the subject. The second setting function 154 sets at least two regions out of the plurality of vascularly-dominated regions and the ischemic region within the region of interest set by the first setting function 153, based on the vascularly-dominated region image generated by the generation function 152.

[0030] The calculation function 155 calculates a ratio between each of the at least two regions set by the second setting function 154 and the region of interest set by the first setting function 153. The output function 156 outputs information about the ratio calculated by the calculation function 155 to the display 140.

[0031] With this configuration, by outputting information regarding the ratio between each vascularly-dominated area and the ischemic area contained in the region of interest and the region of interest, it is possible to present a quantitative indicator of collateral circulation that is directly related to treatment decisions and prognosis.

[0032] Each of the processing functions of the processing circuit 150 described above will be described in detail below.

[0033] In the following, an example will be described in which the target tissue to be diagnosed is the brain. In this case, the first setting function 153 sets a region of interest in the hemisphere that includes the ischemic region of the two hemispheres of the brain.

[0034] FIG. 2 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry 150 according to the first embodiment.

[0035] In this embodiment, the acquisition function 151 acquires medical images of the subject's brain at multiple time phases from the medical image diagnostic device 20 or the medical image storage device 30 .

[0036] Here, the medical image acquired by the acquisition function 151 may be any image as long as it is an image that allows the arrival time of a contrast agent to be grasped. For example, the medical image may be a CT image acquired by an X-ray CT device or an MRI image acquired by an MRI device. Note that the medical image may also be an image acquired by an imaging method that can image the dynamics of blood flow without using a contrast agent, such as ASL (Arterial Spin Labeling).

[0037] In addition, the generation function 152 generates a vascular control area image representing the middle cerebral artery control area, the anterior cerebral artery control area, and the posterior cerebral artery control area contained in the subject's brain based on medical images of multiple time phases acquired by the acquisition function 151.

[0038] For example, the generating function 152 creates a vascular region image showing a vascular region that reflects the presence or absence of an infarct region or collateral blood flow by dividing the brain region using the arrival time of a contrast agent perfused into the brain tissue. For example, the generating function 152 generates a vascular region image by the method described in Patent Document 2.

[0039] Here, the vascular control area image generated by the generation function 152 includes, for example, as shown in (A) of Figure 2, the vascular control areas of the left anterior cerebral artery control area (area "1"), the left middle cerebral artery control area (area "3"), and the left posterior cerebral artery control area (area "5") contained in the left cerebral hemisphere (right side in the figure), and the right anterior cerebral artery control area (area "2"), the right middle cerebral artery control area (area "4"), and the right posterior cerebral artery control area (area "6") contained in the right cerebral hemisphere (left side in the figure).

[0040] In addition, the first setting function 153 uses at least one of the medical images of multiple time phases acquired by the acquisition function 151 to identify the entire area of ​​the cerebral hemisphere opposite the cerebral hemisphere containing the ischemic area, and sets the area obtained by inverting the identified area relative to the median plane of the brain as the area of ​​interest.

[0041] For example, as shown in (A) of FIG. 2, assume that an ischemic region (region "7") is included in the left cerebral hemisphere. In this case, the first setting function 153 determines that the ischemic region is included in the left cerebral hemisphere using the vascular governed region image generated by the generation function 152. Then, the first setting function 153 uses at least one of the medical images of multiple time phases acquired by the acquisition function 151 to identify the entire region of the right cerebral hemisphere, which is opposite to the left cerebral hemisphere containing the ischemic region.

[0042] Thereafter, the first setting function 153 estimates the entire area of ​​the left cerebral hemisphere by inverting the entire area of ​​the right cerebral hemisphere in the vascular governed region image to the left with respect to the median plane of the brain, as shown in (B) of Figure 2. Then, the first setting function 153 sets the estimated entire area of ​​the left cerebral hemisphere as the region of interest (the area surrounded by the dashed line shown in (B) of Figure 2).

[0043] In addition, the second setting function 154 sets at least two regions among the middle cerebral artery controlled region, the anterior cerebral artery controlled region, the posterior cerebral artery controlled region, and the ischemic region within the region of interest set by the first setting function 153 based on the vascular controlled region image generated by the generation function 152.

[0044] For example, as shown in FIG. 2B, the second setting function 154 sets a region governed by the left middle cerebral artery, a region governed by the left anterior cerebral artery, a region governed by the left posterior cerebral artery, and an ischemic region within the region of interest.

[0045] Furthermore, the calculation function 155 calculates the volume ratio between each of the at least two regions set by the second setting function 154 and the region of interest as a ratio between the region of interest and each of the at least two regions.

[0046] For example, the calculation function 155 calculates the volume ratio of each of the at least two regions set by the second setting function 154 to the region of interest as a first volume ratio, and further calculates the volume ratio of each of the at least two regions included in the cerebral hemisphere opposite the cerebral hemisphere containing the ischemic region to the entire region of the cerebral hemisphere opposite the cerebral hemisphere containing the ischemic region as a second volume ratio, and calculates the difference between the first volume ratio and the second volume ratio for each corresponding region.

[0047] For example, the calculation function 155 calculates the volume of the right cerebral hemisphere, which corresponds to the volume of the region of interest, using at least one of the medical images of multiple time phases acquired by the acquisition function 151. Then, the calculation function 155 calculates, as a first volume ratio, the volume ratio of the left middle cerebral artery-served region, the left anterior cerebral artery-served region, the left posterior cerebral artery-served region, and the ischemic region, which are set within the region of interest, to the right cerebral hemisphere.

[0048] For example, as shown in (C) of Figure 2, the calculation function 155 sets the volume of the right cerebral hemisphere, which corresponds to the volume of the region of interest, to 100%, and calculates the first volume ratio for the region served by the left middle cerebral artery, the first volume ratio for the region served by the left anterior cerebral artery, the first volume ratio for the region served by the left posterior cerebral artery, and the first volume ratio for the ischemic region to be 20%, 40%, 30%, and 10%, respectively.

[0049] Furthermore, the calculation function 155 calculates, as a second volume ratio, the volume ratio of each of the right middle cerebral artery-served region, the right anterior cerebral artery-served region, the right posterior cerebral artery-served region, and the ischemic region included in the right cerebral hemisphere to the entire region of the right cerebral hemisphere, using the vascular region image generated by the generation function 152. At this time, since the right cerebral hemisphere does not include an ischemic region, the second volume ratio for the ischemic region is calculated to be zero.

[0050] Then, the calculation function 155 calculates the difference between the first volume ratio and the second volume ratio for each corresponding region on the left and right. At this time, for example, the calculation function 155 subtracts the second volume ratio from the first volume ratio to calculate the increase in volume ratio from the second volume ratio to the first volume ratio as the difference between the first volume ratio and the second volume ratio. Furthermore, the calculation function 155 determines the blood vessel-dominated region in which the volume ratio is increasing as the nutrient region of collateral blood circulation, and calculates the sum of the volume ratios related to the blood vessel-dominated region as the increase in volume ratio related to the nutrient region of collateral blood circulation.

[0051] For example, as shown in (D) of Figure 2, the calculation function 155 calculates the increase in volume ratio for the region served by the left middle cerebral artery, the increase in volume ratio for the region served by the left anterior cerebral artery, the increase in volume ratio for the region served by the left posterior cerebral artery, the increase in volume ratio for the ischemic region, and the increase in volume ratio for the nutrient region of collateral circulation as -40%, +15%, +15%, +10%, and 30%, respectively.

[0052] In addition, the output function 156 outputs to the display 140, for each of the at least two regions set by the second setting function 154, the first volume ratio calculated by the calculation function 155 and information indicating the difference between the first volume ratio and the second volume ratio.

[0053] 2(C), the output function 156 outputs information indicating the first volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery-served region, the left anterior cerebral artery-served region, the left posterior cerebral artery-served region, and the ischemic region. For example, the output function 156 outputs information indicating the first volume ratio for each region in the form of a pie chart.

[0054] 2(D), the output function 156 outputs information indicating the difference between the first volume ratio and the second volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery-served region, the left anterior cerebral artery-served region, the left posterior cerebral artery-served region, and the ischemic region. For example, the output function 156 outputs information indicating the increase in the volume ratio for each region in the form of a list as shown on the left side of FIG.

[0055] The above has described each processing function possessed by the processing circuitry 150. Here, for example, the processing circuitry 150 is realized by a processor. In this case, each of the above-mentioned processing functions is stored in the storage circuitry 120 in the form of a program executable by a computer. Then, the processing circuitry 150 realizes the function corresponding to each program by reading and executing each program stored in the storage circuitry 120. In other words, when each program is read, the processing circuitry 150 has each processing function shown in FIG. 1.

[0056] FIG. 3 is a flowchart showing the processing procedure performed by the processing circuitry 150 according to the first embodiment.

[0057] 3, the processing circuitry 150 first acquires medical images of a target tissue of a subject at multiple time phases from the medical image diagnostic device 20 or the medical image storage device 30 (step S101). This step corresponds to the acquisition function 151. For example, the processing circuitry 150 executes this step by reading out a program corresponding to the acquisition function 151 from the storage circuitry 120 and executing it.

[0058] Next, the processing circuitry 150 generates a vascular control region image representing a plurality of vascular control regions included in the target tissue of the subject based on the medical images of the plurality of time phases (step S102). This step corresponds to the generation function 152. For example, the processing circuitry 150 executes this step by reading out a program corresponding to the generation function 152 from the storage circuitry 120 and executing it.

[0059] Next, the processing circuitry 150 sets a region of interest in the target tissue of the subject (step S103). This step corresponds to the first setting function 153. For example, the processing circuitry 150 executes this step by reading out a program corresponding to the first setting function 153 from the storage circuitry 120 and executing it.

[0060] Next, the processing circuitry 150 sets at least two regions among the plurality of vascularly governed regions and the ischemic region within the region of interest based on the vascularly governed region image (step S104). This step corresponds to the second setting function 154. For example, the processing circuitry 150 executes this step by reading out a program corresponding to the second setting function 154 from the storage circuitry 120 and executing it.

[0061] Next, the processing circuitry 150 calculates the ratio between each of the at least two set regions and the region of interest (step S105). This step corresponds to the calculation function 155. For example, the processing circuitry 150 executes this step by reading out a program corresponding to the calculation function 155 from the storage circuitry 120 and executing it.

[0062] Next, the processing circuitry 150 outputs information about the calculated ratio to the display 140 (step S106). This step corresponds to the output function 156. For example, the processing circuitry 150 executes this step by reading out a program corresponding to the output function 156 from the storage circuitry 120 and executing it.

[0063] As described above, in the first embodiment, the acquisition function 151 acquires medical images of a target tissue of a subject at multiple time phases. The generation function 152 generates a vascular control region image representing multiple vascular control regions included in the target tissue of the subject based on the medical images at multiple time phases. The first setting function 153 sets a region of interest. The second setting function 154 sets at least two regions out of the multiple vascular control regions and the ischemic region within the region of interest based on the vascular control region image. The calculation function 155 calculates a ratio between each of the at least two regions and the region of interest set by the first setting function 153. The output function 156 outputs information related to the ratio.

[0064] With this configuration, by outputting information on the ratio between the vascularly-dominated area and the ischemic area contained in the ROI, it is possible to present a quantitative index of collateral circulation that is directly related to treatment decisions and prognosis, and also to quantitatively grasp the dominant blood vessels within the ROI.

[0065] In the first embodiment, the calculation function 155 calculates the volume ratio between each of the at least two regions and the region of interest as a ratio between each of the at least two regions and the region of interest. This configuration allows information on the volume ratio between each vascular region or ischemic region set within the region of interest and the region of interest to be presented as a quantitative index of collateral circulation. Furthermore, it becomes possible to more accurately grasp the dominant blood vessels within the region of interest.

[0066] In the first embodiment, the target tissue to be diagnosed is the brain. The first setting function 153 sets a region of interest in the hemisphere containing the ischemic region of the two hemispheres of the brain. This configuration makes it possible to present a quantitative index of collateral circulation in the brain.

[0067] In the first embodiment, the first setting function 153 uses at least one medical image from multiple time phases to identify the entire area of ​​the cerebral hemisphere opposite to the cerebral hemisphere containing the ischemic area, and sets the identified area inverted with respect to the median plane of the brain as the region of interest. With this configuration, information regarding the ratio of the entire area of ​​the cerebral hemisphere to each blood vessel-dominated area or the ischemic area can be presented as a quantitative index of collateral circulation.

[0068] In the first embodiment, the calculation function 155 calculates a first volume ratio as a volume ratio to the region of interest for each of at least two regions, and calculates a second volume ratio as a volume ratio to the entire region of the opposite hemisphere for each of the at least two regions included in the opposite hemisphere to the hemisphere containing the ischemic region, and calculates the difference between the first volume ratio and the second volume ratio for each corresponding region. This configuration makes it easy to grasp the increase or decrease in size of each blood vessel-dominated region and the ischemic region.

[0069] Although the first embodiment has been described above, the above-described medical image processing apparatus 100 can be implemented by appropriately modifying part of its configuration. Therefore, the following describes a modified version of the first embodiment as another embodiment. Note that the following embodiments will mainly describe the differences from the first embodiment, and detailed description of overlapping content will be omitted.

[0070] (Second embodiment) For example, in the first embodiment described above, an example was described in which at least one medical image of multiple time phases is used to identify the entire area of ​​the cerebral hemisphere opposite the cerebral hemisphere containing the ischemic area, and a region of interest is set based on that area, but the embodiment is not limited to this.

[0071] For example, a vascularized region image may be used to identify a vascularized region in the cerebral hemisphere opposite to the cerebral hemisphere containing the ischemic region, including a position corresponding to the position of the ischemic region, and a region of interest may be set based on the vascularized region. Such an example will be described below as a second embodiment.

[0072] FIG. 4 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry 150 according to the second embodiment.

[0073] In this embodiment, the first setting function 153 uses the vascular region image generated by the generation function 152 to detect the position of the ischemic region in the cerebral hemisphere containing the ischemic region, and further identifies a vascular region containing a position corresponding to the position of the ischemic region in the cerebral hemisphere opposite to the cerebral hemisphere containing the ischemic region, and sets the region obtained by inverting the identified vascular region with respect to the median plane of the brain as the region of interest.

[0074] For example, as shown in FIG. 4A, assume that an ischemic region (region "7") is included in the left cerebral hemisphere. In this case, the first setting function 153 uses the vascular governed region image to determine that the left cerebral hemisphere includes an ischemic region and detects the position of the ischemic region. Then, the first setting function 153 further uses the vascular governed region image to identify a vascular governed region including a position corresponding to the position of the ischemic region in the right cerebral hemisphere, which is opposite the left cerebral hemisphere including the ischemic region.

[0075] For example, assume that the vascularly-dominated region including the position corresponding to the position of the ischemic region in the right cerebral hemisphere is the right middle cerebral artery-dominated region (region "4"). In this case, the first setting function 153 inverts the right middle cerebral artery-dominated region in the vascularly-dominated region image to the left with respect to the median plane of the brain, as shown in FIG. 4B, and sets the inverted region as the region of interest (the region surrounded by the dashed line shown in FIG. 4B).

[0076] In addition, the second setting function 154 sets at least two regions from the middle cerebral artery controlled region, the anterior cerebral artery controlled region, the posterior cerebral artery controlled region, and the ischemic region within the region of interest set by the first setting function 153, similar to the first embodiment, although the region of interest is different.

[0077] For example, as shown in FIG. 4B, the second setting function 154 sets a region governed by the left middle cerebral artery, a region governed by the left anterior cerebral artery, a region governed by the left posterior cerebral artery, and an ischemic region within the region of interest.

[0078] Furthermore, although the regions of interest are different, the calculation function 155 calculates the volume ratio between each of the at least two regions set by the second setting function 154 and the region of interest, similarly to the first embodiment.

[0079] For example, the calculation function 155 calculates the volume of the right middle cerebral artery governed region, which corresponds to the volume of the region of interest, using the vascular governed region image generated by the generation function 152. Then, the calculation function 155 calculates, as a first volume ratio, the volume ratio of the left middle cerebral artery governed region, the left anterior cerebral artery governed region, the left posterior cerebral artery governed region, and the ischemic region set within the region of interest to the right middle cerebral artery governed region.

[0080] For example, as shown in (C) of Figure 4, the calculation function 155 sets the volume of the right middle cerebral artery-dominated region, which corresponds to the volume of the region of interest, to 100%, and calculates the first volume ratio for the left middle cerebral artery-dominated region, the first volume ratio for the left anterior cerebral artery-dominated region, the first volume ratio for the left posterior cerebral artery-dominated region, and the first volume ratio for the ischemic region to be 30%, 40%, 20%, and 10%, respectively.

[0081] Furthermore, the calculation function 155 calculates, as in the first embodiment, the volume ratio of the right middle cerebral artery-served region, the right anterior cerebral artery-served region, the right posterior cerebral artery-served region, and the ischemic region included in the right cerebral hemisphere to the entire region of the right cerebral hemisphere as a second volume ratio. Then, as in the first embodiment, the calculation function 155 calculates the difference between the first volume ratio and the second volume ratio for each corresponding region on the left and right.

[0082] For example, as shown in (D) of Figure 4, the calculation function 155 calculates the increase in volume ratio for the region served by the left middle cerebral artery, the increase in volume ratio for the region served by the left anterior cerebral artery, the increase in volume ratio for the region served by the left posterior cerebral artery, the increase in volume ratio for the ischemic region, and the increase in volume ratio for the nutrient region of collateral circulation as -30%, +15%, +5%, +10%, and 20%, respectively.

[0083] Furthermore, as in the first embodiment, the output function 156 outputs to the display 140, for each of the at least two regions set by the second setting function 154, the first volume ratio calculated by the calculation function 155 and information indicating the difference between the first volume ratio and the second volume ratio.

[0084] For example, as shown in (C) of Fig. 4, the output function 156 outputs information indicating the first volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery governed region, the left anterior cerebral artery governed region, the left posterior cerebral artery governed region, and the ischemic region. Also, for example, as shown in (D) of Fig. 4, the output function 156 outputs information indicating the difference between the first volume ratio and the second volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery governed region, the left anterior cerebral artery governed region, the left posterior cerebral artery governed region, and the ischemic region.

[0085] As described above, in the second embodiment, the first setting function 153 uses a vascularized region image to detect the position of an ischemic region in a cerebral hemisphere containing the ischemic region, and further identifies a vascularized region in the cerebral hemisphere opposite the cerebral hemisphere containing the ischemic region, including a position corresponding to the position of the ischemic region, and sets the identified vascularized region as a region of interest by inverting it with respect to the median plane of the brain. With this configuration, information regarding the ratio of a specific vascularized region to each vascularized region or the ischemic region can be presented as a quantitative index of collateral circulation.

[0086] (Third embodiment) Furthermore, for example, in the above-described second embodiment, an example has been described in which a vascular region image is used to identify a vascular region including a position corresponding to the position of the ischemic region in the cerebral hemisphere opposite to the cerebral hemisphere including the ischemic region, and a region of interest is set based on the vascular region. However, the embodiment is not limited to this.

[0087] For example, a vascular region governed by a healthy subject image representing a vascular region governed by a healthy subject may be identified, including the position of the ischemic region detected in the vascular region governed by the healthy subject image, and a region of interest may be set based on the vascular region governed by the identified vascular region. Such an example will be described below as a third embodiment.

[0088] FIG. 5 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry 150 according to the third embodiment.

[0089] In this embodiment, the acquisition function 151 further acquires a healthy state vascular governed region image representing a vascular governed region in a healthy state from the medical image diagnostic device 20 or the medical image storage device 30.

[0090] For example, the acquisition function 151 acquires, as a healthy state vascular control area image, an image representing an anatomically defined vascular control area such as an atlas image, or an image of the vascular control area of ​​the subject to be diagnosed after treatment.

[0091] In addition, the first setting function 153 uses the vascular control region image generated by the generation function 152 to detect the position of the ischemic region in the cerebral hemisphere including the ischemic region, and further uses the vascular control region image in a healthy state acquired by the acquisition function 151 to identify the vascular control region including the position of the ischemic region detected in the vascular control region image, and sets the area in which the identified vascular control region is mapped onto the vascular control region image as the region of interest.

[0092] For example, as shown in (A) of FIG. 5, assume that an ischemic region (region "7") is included in the left cerebral hemisphere. In this case, the first setting function 153 determines that an ischemic region is included in the left cerebral hemisphere using the vascular governed region image generated by the generation function 152, and detects the position of the ischemic region. Then, the first setting function 153 uses the vascular governed region image in a healthy state acquired by the acquisition function 151 to identify the vascular governed region that includes the position of the ischemic region detected in the vascular governed region image.

[0093] For example, assume that the vascular control region including the position of the ischemic region in the vascular control region image in a healthy state is the left middle cerebral artery control region (region "3") as shown in FIG. 5(B). In this case, the first setting function 153 estimates the left middle cerebral artery control region in a healthy state in the cerebral hemisphere including the ischemic region by mapping the left middle cerebral artery control region in the vascular control region image in a healthy state onto the vascular control region image as shown in FIG. 5(C). Then, the first setting function 153 sets the estimated vascular control region as a region of interest (the region surrounded by a dashed line in FIG. 5(C)).

[0094] In addition, the second setting function 154, as in the first embodiment, sets at least two regions from the middle cerebral artery controlled region, the anterior cerebral artery controlled region, the posterior cerebral artery controlled region, and the ischemic region within the region of interest set by the first setting function 153.

[0095] For example, as shown in FIG. 5C, the second setting function 154 sets a region governed by the left middle cerebral artery, a region governed by the left anterior cerebral artery, a region governed by the left posterior cerebral artery, and an ischemic region within the region of interest.

[0096] Furthermore, although the regions of interest are different, the calculation function 155 calculates the volume ratio between each of the at least two regions set by the second setting function 154 and the region of interest, similarly to the first embodiment.

[0097] For example, the calculation function 155 calculates the volume of the left middle cerebral artery governed region, which corresponds to the volume of the region of interest, using the healthy state vascular governed region image acquired by the acquisition function 151. Then, the calculation function 155 calculates the volume ratio of the left middle cerebral artery governed region, the left anterior cerebral artery governed region, the left posterior cerebral artery governed region, and the ischemic region set within the region of interest to the left middle cerebral artery governed region as a first volume ratio.

[0098] For example, as shown in (D) of Figure 5, the calculation function 155 sets the volume of the left middle cerebral artery-dominated region, which corresponds to the volume of the region of interest, to 100%, and calculates the first volume ratio for the left middle cerebral artery-dominated region, the first volume ratio for the left anterior cerebral artery-dominated region, the first volume ratio for the left posterior cerebral artery-dominated region, and the first volume ratio for the ischemic region to be 30%, 40%, 20%, and 10%, respectively.

[0099] Furthermore, the calculation function 155 calculates, as in the first embodiment, the volume ratio of the right middle cerebral artery-served region, the right anterior cerebral artery-served region, the right posterior cerebral artery-served region, and the ischemic region included in the right cerebral hemisphere to the entire region of the right cerebral hemisphere as a second volume ratio. Then, as in the first embodiment, the calculation function 155 calculates the difference between the first volume ratio and the second volume ratio for each corresponding region on the left and right.

[0100] For example, as shown in (E) of Figure 5, the calculation function 155 calculates the increase in volume ratio for the region served by the left middle cerebral artery, the increase in volume ratio for the region served by the left anterior cerebral artery, the increase in volume ratio for the region served by the left posterior cerebral artery, the increase in volume ratio for the ischemic region, and the increase in volume ratio for the nutrient region of collateral circulation as -30%, +15%, +5%, +10%, and 20%, respectively.

[0101] Furthermore, as in the first embodiment, the output function 156 outputs to the display 140, for each of the at least two regions set by the second setting function 154, the first volume ratio calculated by the calculation function 155 and information indicating the difference between the first volume ratio and the second volume ratio.

[0102] 5(D), the output function 156 outputs information indicating the first volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery-served region, the left anterior cerebral artery-served region, the left posterior cerebral artery-served region, and the ischemic region. Also, as shown in FIG. 5(E), the output function 156 outputs information indicating the difference between the first volume ratio and the second volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery-served region, the left anterior cerebral artery-served region, the left posterior cerebral artery-served region, and the ischemic region.

[0103] As described above, in the third embodiment, the acquisition function 151 further acquires a vascular region image in a healthy state, which represents a vascular region in a healthy state. The first setting function 153 then uses the vascular region image to detect the position of the ischemic region in the cerebral hemisphere containing the ischemic region, and further uses the vascular region image in a healthy state to identify a vascular region including the position of the ischemic region detected in the vascular region image. The first setting function 153 then sets a region obtained by mapping the identified vascular region onto the vascular region image as a region of interest. This configuration allows information regarding the ratio of the vascular region in a healthy state to each vascular region or the ischemic region to be presented as a quantitative index of collateral circulation.

[0104] (Fourth embodiment) Furthermore, for example, in the above-described third embodiment, an example has been described in which a vascular control region image in a healthy state representing a vascular control region in a healthy state is used to identify a vascular control region including the position of an ischemic region detected in the vascular control region image, and a region of interest is set based on the vascular control region, but the embodiment is not limited to this.

[0105] For example, a hypoperfused region in a cerebral hemisphere containing an ischemic region may be identified using a perfusion image of the same subject, and a region of interest may be set based on the hypoperfused region. Such an example will be described below as a fourth embodiment.

[0106] FIG. 6 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry 150 according to the fourth embodiment.

[0107] In this embodiment, the acquisition function 151 further acquires perfusion images of the subject to be diagnosed from the medical image diagnostic apparatus 20 or the medical image storage apparatus 30 .

[0108] In addition, the first setting function 153 uses the perfusion image acquired by the acquisition function 151 to identify a hypoperfused area in the cerebral hemisphere including the ischemic area, and sets the area in which the identified hypoperfused area is mapped onto the vascular control area image as the region of interest.

[0109] At this time, for example, the first setting function 153 identifies a hypoperfusion region based on perfusion parameters obtained from a perfusion image. For example, the first setting function 153 identifies a region where Tmax exceeds 6 seconds or a region where contralateral cerebral blood flow (CBF) is less than 30% as a hypoperfusion region.

[0110] For example, as shown in FIG. 6A, assume that an ischemic region (region "7") is included in the left cerebral hemisphere. In this case, the first setting function 153 determines that the left cerebral hemisphere includes an ischemic region using the vascular governed region image generated by the generation function 152, and detects the location of the ischemic region. Then, as shown in FIG. 6B, the first setting function 153 identifies a hypoperfusion region (the region marked with diagonal lines in FIG. 6B) in the cerebral hemisphere including the ischemic region using the perfusion image acquired by the acquisition function 151.

[0111] Then, as shown in (C) of FIG. 6, the first setting function 153 maps the hypoperfusion region in the perfusion image onto the vascular governed region image, and sets the mapped region as a region of interest (the region surrounded by a dashed line in (C) of FIG. 6).

[0112] In addition, the second setting function 154 sets at least two regions from the middle cerebral artery controlled region, the anterior cerebral artery controlled region, the posterior cerebral artery controlled region, and the ischemic region within the region of interest set by the first setting function 153, similar to the first embodiment, although the region of interest is different.

[0113] For example, as shown in FIG. 6C, the second setting function 154 sets a region governed by the left middle cerebral artery, a region governed by the left anterior cerebral artery, a region governed by the left posterior cerebral artery, and an ischemic region within the region of interest.

[0114] Furthermore, although the regions of interest are different, the calculation function 155 calculates the volume ratio between each of the at least two regions set by the second setting function 154 and the region of interest, similarly to the first embodiment.

[0115] For example, the calculation function 155 calculates the volume of a hypoperfusion region corresponding to the volume of the region of interest using the perfusion image acquired by the acquisition function 151. Then, the calculation function 155 calculates, as a first volume ratio, the volume ratio of the region served by the right middle cerebral artery to the region served by the left middle cerebral artery, the region served by the left anterior cerebral artery, the region served by the left posterior cerebral artery, and the ischemic region included in the region of interest.

[0116] For example, as shown in (D) of Figure 6, the calculation function 155 sets the volume of the hypoperfusion region corresponding to the volume of the region of interest as 100%, and calculates the first volume ratio for the region served by the left middle cerebral artery, the first volume ratio for the region served by the left anterior cerebral artery, the first volume ratio for the region served by the left posterior cerebral artery, and the first volume ratio for the ischemic region as 10%, 40%, 20%, and 30%, respectively.

[0117] Furthermore, the calculation function 155 calculates, as in the first embodiment, the volume ratio of the right middle cerebral artery-served region, the right anterior cerebral artery-served region, the right posterior cerebral artery-served region, and the ischemic region included in the right cerebral hemisphere to the entire region of the right cerebral hemisphere as a second volume ratio. Then, as in the first embodiment, the calculation function 155 calculates the difference between the first volume ratio and the second volume ratio for each corresponding region on the left and right.

[0118] For example, as shown in (E) of Figure 6, the calculation function 155 calculates the increase in volume ratio for the region served by the left middle cerebral artery, the increase in volume ratio for the region served by the left anterior cerebral artery, the increase in volume ratio for the region served by the left posterior cerebral artery, the increase in volume ratio for the ischemic region, and the increase in volume ratio for the nutrient region of collateral circulation as -50%, +15%, +5%, +30%, and 20%, respectively.

[0119] Furthermore, as in the first embodiment, the output function 156 outputs to the display 140, for each of the at least two regions set by the second setting function 154, the first volume ratio calculated by the calculation function 155 and information indicating the difference between the first volume ratio and the second volume ratio.

[0120] For example, as shown in (D) of Fig. 6, the output function 156 outputs information indicating the first volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery governed region, the left anterior cerebral artery governed region, the left posterior cerebral artery governed region, and the ischemic region. Also, for example, as shown in (E) of Fig. 6, the output function 156 outputs information indicating the difference between the first volume ratio and the second volume ratio calculated by the calculation function 155 for each of the left middle cerebral artery governed region, the left anterior cerebral artery governed region, the left posterior cerebral artery governed region, and the ischemic region.

[0121] As described above, in the fourth embodiment, the acquisition function 151 further acquires a perfusion image of the subject. Then, the first setting function 153 uses the perfusion image to identify a hypoperfusion region in a cerebral hemisphere including an ischemic region, and sets the identified hypoperfusion region as a region of interest by mapping the identified hypoperfusion region onto a vascular-dominated region image. This configuration allows information regarding the ratio of the hypoperfusion region to each vascular-dominated region or the ischemic region to be presented as a quantitative index of collateral circulation.

[0122] (Fifth embodiment) Furthermore, for example, in the above-described first to fourth embodiments, examples have been described in which the ratio between each region and the region of interest is calculated for each of multiple vascular control regions and ischemic regions, but the embodiments are not limited to this.

[0123] For example, each region may be classified into a plurality of blood flow patterns including an antegrade perfusion region, a retrograde perfusion region, and an ischemic region, and the ratio of each region to the region of interest may be calculated for each blood flow pattern. Such an example will be described below as a fifth embodiment.

[0124] FIG. 7 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry 150 according to the fifth embodiment.

[0125] In this embodiment, the calculation function 155 classifies at least two regions set by the second setting function 154 into a plurality of blood flow patterns including an antegrade perfusion region, a retrograde perfusion region, and an ischemic region, and calculates the ratio between each region and the region of interest for each blood flow pattern.

[0126] Here, an antegrade perfusion region is a region in which the arteries nourished by it have not changed compared to when the patient is healthy, a retrograde perfusion region is a region in which the arteries nourished by it are different compared to when the patient is healthy, and an ischemic region is a region in which the arrival time of the contrast agent is longer than a certain time and in which no perfusion is observed within that certain time.

[0127] Specifically, the calculation function 155 calculates the increase for each vascularly governed area in the same manner as in any of the first to fourth embodiments, and then classifies the vascularly governed area where the volume ratio is decreasing as an antegrade perfusion area, and classifies the vascularly governed area where the volume ratio is increasing as a retrograde perfusion area. In addition, the calculation function 155 classifies the ischemic area as an ischemic area.

[0128] For example, as shown in Fig. 4, suppose that the increase in the volume ratio for the region served by the left middle cerebral artery, the increase in the volume ratio for the region served by the left anterior cerebral artery, and the increase in the volume ratio for the region served by the left posterior cerebral artery are -30%, +15%, and +5%, respectively. In this case, the calculation function 155 classifies the region served by the left middle cerebral artery as an antegrade perfusion region, the region served by the left anterior cerebral artery and the region served by the left posterior cerebral artery as retrograde perfusion regions, and the ischemic region as an ischemic region.

[0129] Then, the calculation function 155 calculates the first volume ratio, which is the volume ratio to the region of interest, for each blood flow pattern by summing up the first volume ratios for each blood vessel governed region classified into the same blood flow pattern.

[0130] For example, as shown in the example of Fig. 4, it is assumed that the first volume ratio for the region served by the left middle cerebral artery, the first volume ratio for the region served by the left anterior cerebral artery, the first volume ratio for the region served by the left posterior cerebral artery, and the first volume ratio for the ischemic region are 30%, 40%, 20%, and 10%, respectively. In this case, the calculation function 155 calculates the first volume ratio for the antegrade perfusion region (Anterograde), the first volume ratio for the retrograde perfusion region (Retrograde), and the first volume ratio for the ischemic region (No flow) to be 30%, 60%, and 10%, respectively, assuming that the volume of the region of interest is 100%, as shown in Fig. 7(C).

[0131] Furthermore, the calculation function 155 calculates the difference between the first volume ratio and the second volume ratio for each blood flow pattern by summing up the differences between the first volume ratio and the second volume ratio for each blood vessel governed area classified into the same blood flow pattern. At this time, for example, the calculation function 155 calculates the increase in the volume ratio from the second volume ratio to the first volume ratio as the difference between the first volume ratio and the second volume ratio for each blood flow pattern.

[0132] For example, as shown in (D) of Figure 7, the calculation function 155 calculates the increase in the volume ratio for the antegrade perfusion region (anterograde), the increase in the volume ratio for the retrograde perfusion region (retrograde), the increase in the volume ratio for the ischemic region (no flow), and the increase in the volume ratio for the nutrient region of collateral circulation as -30%, +20%, +10%, and 20%, respectively.

[0133] In addition, the output function 156 outputs to the display 140, for each blood flow pattern, the first volume ratio calculated by the calculation function 155 and information indicating the difference between the first volume ratio and the second volume ratio.

[0134] 7(C), the output function 156 outputs information indicating the first volume ratio calculated by the calculation function 155 for each of the antegrade perfusion region (Anterograde), the retrograde perfusion region (Retrograde), and the ischemic region (No flow). Also, for example, as shown in FIG. 7(D), the output function 156 outputs information indicating the difference between the first volume ratio and the second volume ratio calculated by the calculation function 155 for each of the antegrade perfusion region (Anterograde), the retrograde perfusion region (Retrograde), and the ischemic region (No flow).

[0135] As described above, in the fifth embodiment, the calculation function 155 classifies at least two regions into a plurality of blood flow patterns including an antegrade perfusion region, a retrograde perfusion region, and an ischemic region, and calculates the ratio of each region to the region of interest for each blood flow pattern. With this configuration, information on the ratio of the region of interest to each vascularly-served region or the ischemic region for each blood flow pattern can be presented as a quantitative index of collateral circulation.

[0136] (Sixth embodiment) Furthermore, for example, in the above-described fifth embodiment, an example has been described in which information relating to the ratio calculated for each blood flow pattern is output, but the embodiment is not limited to this.

[0137] For example, a blood vessel governed region image representing at least one range of a plurality of blood flow patterns may be further output. Such an example will be described below as a sixth embodiment.

[0138] FIG. 8 is a diagram for explaining an example of processing performed by each processing function of the processing circuitry 150 according to the sixth embodiment.

[0139] In this embodiment, the calculation function 155 classifies at least two regions set by the second setting function 154 into multiple blood flow patterns including an antegrade perfusion region, a retrograde perfusion region, and an ischemic region, as in the fifth embodiment.

[0140] Furthermore, the output function 156 further outputs to the display 140 a blood vessel governed region image showing the region of at least one blood flow pattern among the plurality of blood flow patterns classified by the calculation function 155.

[0141] For example, as shown in (D) of Figure 8, the output function 156 outputs a vascular region image showing the left anterior cerebral artery region and the left posterior cerebral artery region, which are classified as retrograde perfusion regions, in a display mode different from regions with other blood flow patterns.

[0142] Alternatively, the output function 156 may display the vascular distribution area classified as an antegrade perfusion area in a different display mode.

[0143] Here, any method for changing the display mode of the blood flow pattern region may be used as long as it allows the region to be distinguished from other regions. For example, the region may be displayed in a different color, pattern, texture, or the like.

[0144] As described above, in the sixth embodiment, the output function 156 further outputs a blood vessel governed region image showing the region of at least one blood flow pattern among the plurality of blood flow patterns. With this configuration, it becomes possible to easily grasp the region of a specific blood flow pattern on the blood vessel governed region image.

[0145] (Seventh embodiment) Furthermore, for example, in the above-described first to sixth embodiments, examples have been described in which the ratios of a plurality of blood vessel governed regions and ischemic regions to the region of interest are calculated, but the embodiments are not limited to this.

[0146] For example, the suitability of treatment for the target tissue may be determined based on the ratio of each region to the region of interest. Such an example will be described below as a seventh embodiment.

[0147] FIG. 9 is a diagram illustrating an example of the configuration of a medical image processing apparatus according to the seventh embodiment.

[0148] For example, as shown in Fig. 9, in the medical image processing apparatus 200 according to this embodiment, the processing circuitry 250 further has a determination function 257 in addition to the acquisition function 151, the generation function 152, the first setting function 153, the second setting function 154, the calculation function 155, and the output function 156 shown in Fig. 1. Here, the determination function 257 is an example of a determination unit.

[0149] The determination function 257 determines whether or not a treatment is appropriate for the target tissue of the subject based on the ratios calculated by the calculation function 155 for each of the at least two regions and the region of interest.

[0150] FIG. 10 is a diagram for explaining an example of processing performed by the determination function 257 of the processing circuitry 250 according to the seventh embodiment.

[0151] For example, as shown in Fig. 10, the determination function 257 determines whether a treatment is appropriate for the subject's brain by using a decision tree whose leaves represent treatment methods. Here, it is assumed that, as in the fourth embodiment, a region of interest is set based on a hypoperfusion region identified using a perfusion image, and an increase in volume ratio is calculated for each region set within the region of interest.

[0152] For example, the determination function 257 first determines whether the increase in the volume ratio of the ischemic region (No flow) calculated by the calculation function 155 is greater than 50%. If the increase in the volume ratio of the ischemic region (No flow) is greater than 50%, the determination function 257 determines that the treatment method is "not suitable for treatment."

[0153] On the other hand, if the increase in the volume ratio of the ischemic region (No flow) is 50% or less, the determination function 257 determines whether the increase in the volume ratio of the nutrient region of collateral circulation calculated by the calculation function 155 is greater than 50%. If the increase in the volume ratio of the nutrient region of collateral circulation is greater than 50%, the determination function 257 determines the treatment method to be "rt-PA injection only."

[0154] On the other hand, if the increase in the volume ratio of the nutritional region of the collateral circulation is 50% or less, the determination function 257 determines whether the volume of the region where Tmax is greater than 8 seconds among the low perfusion regions in the perfusion image acquired by the acquisition function 151 is 30 mm 3 Then, determine whether the volume of the region where Tmax is greater than 8s is 30 mm 3 If the Tmax is greater than 8 seconds, the determination function 257 determines that the treatment method is "not applicable." 3 If the following is true, the determination function 257 determines the treatment method to be "thrombectomy therapy."

[0155] Although the example in which the determination function 257 uses the increase in the volume ratio related to the ischemic region has been described here, the index value used for determining the suitability of treatment is not limited to this. For example, the increase in the volume ratio related to the blood vessel governed region may be used, or the increase in the volume ratio related to the blood flow pattern described in the fifth embodiment may be used.

[0156] The above has described each processing function possessed by the processing circuitry 250. Here, for example, the processing circuitry 250 is realized by a processor. In this case, each of the above-described processing functions is stored in the storage circuitry 120 in the form of a program executable by a computer. The processing circuitry 250 then reads and executes each program stored in the storage circuitry 120 to realize the function corresponding to each program. In other words, the processing circuitry 250 has each processing function shown in FIG. 9 when each program has been read.

[0157] FIG. 11 is a flowchart showing the processing procedure performed by the processing circuitry 250 according to the seventh embodiment.

[0158] For example, as shown in FIG. 11, the processing circuit 250 executes the same processes as steps S101 to S106 shown in FIG.

[0159] Next, the processing circuitry 250 determines whether the target tissue of the subject is suitable for treatment based on the calculated ratios between each of the at least two regions and the region of interest (step S207). This step corresponds to the determination function 257. For example, the processing circuitry 250 executes this step by reading a program corresponding to the determination function 257 from the storage circuitry 120 and executing it.

[0160] As described above, in the seventh embodiment, the determination function 257 determines the suitability of treatment for the target tissue of the subject based on the ratios of at least two regions to the region of interest. With this configuration, it is possible to more appropriately determine the treatment method for the target tissue of the subject.

[0161] (Other embodiments) In the above-described embodiment, an example in which the target tissue to be diagnosed is the brain has been described, but the embodiment is not limited to this. For example, the medical image processing device described in the above-described embodiment can be similarly applied to cases in which the target tissue is another organ or organs. An example of the other organ or organ referred to here is the heart.

[0162] In the above-described embodiment, an example has been described in which the first setting function 153 sets a region of interest using a vascular governed region image, a medical image of multiple time phases, a vascular governed region image in a healthy state, or a perfusion image. However, the embodiment is not limited to this. For example, the first setting function 153 may receive, via the input interface 130, an operation from the operator to specify a range to be set as a region of interest on an image depicting a target tissue, and set the received range as the region of interest.

[0163] The configuration of the medical image processing device described in the above-mentioned embodiment can also be applied to a medical image diagnostic device. In this case, a processing circuit included in a console device or the like of the medical image diagnostic device has the above-mentioned acquisition function, generation function, first setting function, second setting function, calculation function, output function, and determination function.

[0164] Furthermore, in the above-described embodiments, examples have been described in which the acquisition unit, generation unit, first setting unit, second setting unit, calculation unit, output unit, and determination unit in this specification are realized by the acquisition function, generation function, first setting function, second setting function, calculation function, output function, and determination function of a processing circuit, respectively, but the embodiments are not limited to this. For example, the acquisition unit, generation unit, first setting unit, second setting unit, calculation unit, output unit, and determination unit in this specification may be realized by the acquisition function, generation function, first setting function, second setting function, calculation function, output function, and determination function described in the embodiments, or the same functions may be realized by hardware only, software only, or a combination of hardware and software.

[0165] Furthermore, in the above-described embodiment, an example in which the processing circuit is realized by a single processor has been described, but the embodiment is not limited thereto. For example, the processing circuit may be configured by combining multiple independent processors, and each processor may execute a program to realize each processing function. Furthermore, each processing function of the processing circuit may be realized by being appropriately distributed or integrated among a single or multiple processing circuits. Furthermore, each processing function of the processing circuit may be realized by a combination of hardware and software, such as a circuit. Furthermore, while the above-described embodiment describes an example in which programs corresponding to each processing function are stored in a single storage circuit, the embodiment is not limited thereto. For example, a configuration in which programs corresponding to each processing function are distributed and stored among multiple storage circuits, and the processing circuit reads and executes each program from each storage circuit, may also be used.

[0166] Furthermore, the term "processor" used in the description of the above-mentioned embodiments refers to circuits such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). Here, instead of storing a program in a memory circuit, the processor may be configured so that the program is directly embedded in the circuit. In this case, the processor realizes its function by reading and executing the program embedded in the circuit. Furthermore, each processor in the present embodiment is not limited to being configured as a single circuit for each processor, but may also be configured as a single processor by combining multiple independent circuits to realize its function.

[0167] Here, the program executed by the processor is provided in advance in a read-only memory (ROM) or a storage circuit. The program may be provided by being recorded on a computer-readable, non-transitory storage medium such as a compact disk (CD)-ROM, a flexible disk (FD), a recordable CD-R (CD-R), or a digital versatile disk (DVD) in a format that can be installed or executed on these devices. The program may also be provided or distributed by being stored on a computer connected to a network such as the Internet and downloaded via the network. For example, the program may be composed of modules including the above-described processing functions. In actual hardware, a CPU reads and executes the program from a storage medium such as a ROM, whereby each module is loaded into a main memory device and generated on the main memory device.

[0168] In addition, in the above-described embodiments and modifications, the components of each device shown in the drawings are functional concepts and do not necessarily have to be physically configured as shown. In other words, the specific form of distribution or integration of each device is not limited to that shown in the drawings, and all or part of the devices can be functionally or physically distributed or integrated in any unit depending on various loads, usage conditions, etc. Furthermore, all or any part of the processing functions performed by each device can be realized by a CPU and a program analyzed and executed by the CPU, or can be realized as hardware using wired logic.

[0169] Furthermore, among the processes described in the above-mentioned embodiments and modifications, all or part of the processes described as being performed automatically can be performed manually, or all or part of the processes described as being performed manually can be performed automatically using a known method.In addition, the information including the processing procedures, control procedures, specific names, various data and parameters shown in the above documents and drawings can be changed as desired unless otherwise specified.

[0170] The various data handled in this specification are typically digital data.

[0171] According to at least one of the embodiments described above, it is possible to present a quantitative index of collateral circulation that is directly related to treatment decisions and prognosis.

[0172] Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0173] 100 Medical image processing device 150,250 processing circuit 151 Acquisition Function 152 Generation function 153 First Setting Function 154 Second Setting Function 155 Calculation Function 156 Output Function 257 Judgment Function

Claims

1. an acquisition unit that acquires medical images of a target tissue of a subject at multiple time phases; a generating unit that generates a vascular region image representing a plurality of vascular regions included in the target tissue based on the medical images of the plurality of time phases; a first setting unit that sets a region of interest in a region including an ischemic region of the target tissue in the blood vessel governed region image; a second setting unit that sets at least two regions of the plurality of blood vessel governed regions and the ischemic region within the region of interest based on the blood vessel governed region image; a calculation unit that calculates a ratio for each of the at least two regions and the region of interest; an output unit that outputs information about the ratio; A medical image processing device comprising:

2. the calculation unit calculates a volume ratio between each of the at least two regions and the region of interest as a ratio between each of the at least two regions and the region of interest; The medical image processing device according to claim 1 .

3. the target tissue is the brain; the first setting unit sets the region of interest in a cerebral hemisphere including the ischemic region, of the two cerebral hemispheres of the brain, in the vascular governed region image; The medical image processing device according to claim 1 or 2.

4. the first setting unit identifies an entire region of the cerebral hemisphere opposite to the cerebral hemisphere including the ischemic region using at least one of the medical images of the multiple time phases, and sets the identified region as the region of interest by inverting it with respect to the median plane of the brain. The medical image processing device according to claim 3 .

5. the first setting unit detects a position of the ischemic region in the cerebral hemisphere including the ischemic region using the vascularized region image, and further specifies a vascularized region including a position corresponding to the position of the ischemic region in the cerebral hemisphere opposite to the cerebral hemisphere including the ischemic region, and sets the specified vascularized region as the region of interest by inverting it with respect to the median plane of the brain. The medical image processing device according to claim 3 .

6. the acquisition unit further acquires a healthy state vascular governed region image representing a vascular governed region in a healthy state; the first setting unit uses the vascular governed region image to detect the position of the ischemic region in the cerebral hemisphere including the ischemic region, and further uses the vascular governed region image in a healthy state to identify a vascular governed region including the position of the ischemic region detected in the vascular governed region image, and sets a region obtained by mapping the identified vascular governed region onto the vascular governed region image as the region of interest. The medical image processing device according to claim 3 .

7. the acquisition unit further acquires a perfusion image of the subject; the first setting unit identifies a hypoperfusion region in the cerebral hemisphere including the ischemic region using the perfusion image, and sets a region obtained by mapping the identified hypoperfusion region onto the vascular-dominated region image as the region of interest. The medical image processing device according to claim 3 .

8. the calculation unit calculates a volume ratio of each of the at least two regions to the region of interest as a first volume ratio, and further calculates a volume ratio of each of the two regions included in the cerebral hemisphere opposite to the cerebral hemisphere including the ischemic region to the entire region of the cerebral hemisphere opposite to the cerebral hemisphere including the ischemic region as a second volume ratio, and calculates a difference between the first volume ratio and the second volume ratio for each corresponding region.

8. The medical image processing device according to claim 3.

9. The plurality of vascular distribution areas are a middle cerebral artery distribution area, an anterior cerebral artery distribution area, and a posterior cerebral artery distribution area.

9. The medical image processing device according to claim 3.

10. the calculation unit classifies the at least two regions into a plurality of blood flow patterns including an antegrade perfusion region, a retrograde perfusion region, and an ischemic region, and calculates the ratio for each of the blood flow patterns. The medical image processing device according to any one of claims 1 to 9.

11. the output unit further outputs the blood vessel governed region image displaying a region of at least one blood flow pattern among the plurality of blood flow patterns. The medical image processing device according to claim 10.

12. a determination unit for determining whether a treatment is appropriate for the target tissue based on a ratio between each of the at least two regions and the region of interest; The medical image processing device according to any one of claims 1 to 11.

13. acquiring medical images of a target tissue of a subject at multiple time phases; generating a vascular region image representing a plurality of vascular regions included in the target tissue based on the medical images of the plurality of time phases; setting a region of interest in a region including an ischemic region of the target tissue in the vascular governed region image; setting at least two regions of the plurality of vascularly-dominated regions and the ischemic region within the region of interest based on the vascularly-dominated region image; calculating a ratio for each of the at least two regions and the region of interest; outputting information about the ratio; A medical image processing method comprising:

Images