JP2011072534A - Image processor and medical image diagnostic system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a diagnosis, based on a virtual endoscope image, more efficiently. <P>SOLUTION: A 3D image data memory 33 stores a 3D X-ray CT image. A VE image generator 34 generates a VE image resulting from the perspective projection of a 3D X-ray CT image from a viewpoint position. An image cut position decision part 35 determines a cut position so that it covers the region of concern. A synthesizing VE image generator 36 generates a synthesizing VE image from the VE image where the viewpoint position side regarding the cut position is cut off. An MPR image generator 37 generates an MPR image of the 3D X-ray CT image at the cut position. An image region decision part 38 determines the air region containing the region of concern to be a non-display part of the MPR image. A synthesized image generation part 39 generates a synthesized image, in which synthesis is made between the synthesizing VE image region equivalent to the non-display MPR image region part and an MPR image region equivalent to this region except the MPR non-display region part. A display control part 310 displays the synthesized image on a display 32. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image processing apparatus and a medical image diagnostic apparatus.

  Conventionally, as an image display method of three-dimensional image data collected by a medical image diagnostic apparatus such as an X-ray CT apparatus (CT), a magnetic resonance imaging (MRI) apparatus, an ultrasonic diagnostic apparatus, etc., a virtual An endoscope (VE: Virtual Endoscopy) display method (hereinafter referred to as VE method) is known. For example, the VE method is widely used as a display method (CTC: CT Colonography) of a three-dimensional X-ray CT image obtained by photographing the large intestine in a large intestine analysis system for performing preoperative diagnosis including a screening test.

  The VE method is a method of generating a projection image by a perspective projection method using a viewpoint set in three-dimensional image data. Specifically, in the VE method, parameters including “viewpoint position”, “line-of-sight direction”, and “viewing angle around the line-of-sight direction” are set inside the organ included in the three-dimensional image data. In the VE method, a projection image is generated by perspectively projecting three-dimensional image data radially from a viewpoint position in a range determined by a viewing direction and a viewing angle.

  A projection image generated by the VE method is an image similar to an endoscopic image obtained by observing the surface (inner wall) inside the organ with an endoscope, and is called a virtual endoscopic image (VE image). FIG. 10 is a diagram for explaining a virtual endoscopic image. For example, referring to a VE image of the large intestine as shown in FIG. 10, the doctor can observe the presence / absence of the large intestine polyp on the inner wall of the large intestine, the size of the large intestine polyp, and the like. In addition, by arbitrarily changing the parameters, the doctor can observe a site that could not be observed with an endoscope by using a VE image.

  By the way, for the doctor, information in the organ (tissue) of the region to be observed is also important in performing image diagnosis. For example, it is important for a doctor to perform image diagnosis to observe how much a large intestine polyp confirmed on the inner wall of the large intestine by a VE image of the large intestine spreads in the tissue of the large intestine.

  For this reason, a technique for displaying a composite image obtained by combining a cross-sectional image obtained by cutting three-dimensional image data at a predetermined cross-sectional position with a VE image is known (see, for example, Patent Document 1). FIG. 11 is a diagram for explaining the prior art.

  First, as shown in FIG. 11, a VE image as shown in FIG. 10 is generated based on the viewpoint position set in the lumen of the large intestine, the viewing direction (for example, the core line of the lumen), and the viewing angle. Then, the cutting position of the VE image and the cross-sectional position for generating the cross-sectional image are determined based on a predetermined distance set in advance. Specifically, as shown in FIG. 11, a cross section perpendicular to the line-of-sight direction is determined as a cutting position at a position advanced from the viewpoint position by a predetermined distance in the line-of-sight direction.

  Then, as shown in FIG. 11, an area on the sight line side from the cutting position is cut from the VE image to generate a synthesis VE image, and an MPR (Multi-Plate) at the cutting position is generated from the three-dimensional X-ray CT image of the large intestine. Planar Reformat) image is generated. Then, as shown in FIG. 11, a composite image is generated by combining the composite VE image and the MPR image.

  The doctor can observe not only the inner wall surface of the observation target region but also the CT value in the tissue of the observation target region by referring to the composite image generated by such a technique. As a result, the VE image is used. The image diagnosis can be performed efficiently.

Japanese Patent Laid-Open No. 11-76228

  By the way, the conventional technology described above may not always be able to efficiently perform image diagnosis using a VE image. FIG. 12 is a diagram for explaining the problems of the prior art.

  In the above-described conventional technique, a composite image is generated using a composite VE image cut from a VE image within a set viewing angle range. Therefore, when a lumen other than the observation target region is included in the range determined by the viewing angle, as shown in FIG. 12A, the composite image includes a lumen other than the observation target region (colon). The inner wall is also drawn at the same time. For this reason, even if the doctor refers to the composite image, the doctor cannot easily determine the region observed in the VE image.

  Further, in the above-described conventional technique, the composition VE image is generated using a cutting position determined by a predetermined distance and a line-of-sight direction set in advance. For this reason, depending on the setting of the predetermined distance and the line-of-sight direction, the cutting position may be set to the outside of the organ to be observed or set to a lumen different from the observation target region. In this case, as shown in FIG. 12B, only the lumen (colon inner wall) other than the observation target region is depicted in the composite image.

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and an image processing apparatus and medical image diagnosis that can efficiently perform image diagnosis using a virtual endoscopic image. An object is to provide an apparatus.

  In order to solve the above-described problems and achieve the object, the present invention according to claim 1 is a projection image from three-dimensional medical image data by a perspective projection method using setting information including a viewpoint position, a line-of-sight direction, and a viewing angle. A projection image generation unit that generates a cutting position, a cutting position determination unit that determines a cutting position that includes a region of interest determined by the setting information in the projection image generated by the projection image generation unit, and the projection image generation unit First image generating means for generating a first image by cutting a region located on the viewpoint position side with respect to the cutting position determined by the cutting position determining means from the projection image generated by And a second image for generating a cross-sectional image of the three-dimensional medical image data at the cutting position determined by the cutting position determining means as a second image Generating means, area determining means for determining an air area including the region of interest in the second image generated by the second image generating means, and area determining means for the first image determined by the area determining means. A combined image generating unit that generates a combined image by combining a region corresponding to the air region and a region corresponding to a region other than the air region determined by the region determining unit in the second image; And display control means for controlling the composite image generated by the composite image generation means to be displayed on a predetermined display unit.

  According to a third aspect of the present invention, there is provided the image data collecting means for collecting the three-dimensional medical image data and the image data collecting means by the perspective projection method using the setting information including the viewpoint position, the line-of-sight direction, and the viewing angle. A cutting image generation unit that generates a projection image from the collected three-dimensional medical image data, and a cutting position that includes a region of interest determined by the setting information is determined by the projection image generated by the projection image generation unit. A cutting position determining unit and a region located on the viewpoint position side with respect to the cutting position determined by the cutting position determining unit are cut from the projection image generated by the projection image generating unit by first cutting First image generating means for generating an image of the three-dimensional medical image at the cutting position determined by the cutting position determining means A second image generating means for generating a cross-sectional image of the data as a second image, and an area determination for determining an air area including the region of interest in the second image generated by the second image generating means; A region corresponding to the air region determined by the region determination unit in the first image, and a region corresponding to a region other than the air region determined by the region determination unit in the second image. And a display control means for controlling the composite image generated by the composite image generation means to be displayed on a predetermined display unit. Features.

  According to the first or third aspect of the present invention, it is possible to efficiently perform image diagnosis using a virtual endoscopic image.

FIG. 1 is a diagram illustrating the configuration of the image processing apparatus according to the first embodiment. FIG. 2 is a diagram for explaining the VE image generation unit. FIG. 3 is a diagram for explaining the cutting position determination unit. FIG. 4 is a diagram for explaining the composition VE image generation unit. FIG. 5 is a diagram for explaining the MPR image generation unit. FIG. 6 is a diagram for explaining the region determination unit according to the first embodiment. FIG. 7 is a diagram for explaining the composite image generation unit. FIG. 8 is a flowchart for explaining processing of the image processing apparatus according to the first embodiment. FIG. 9 is a diagram for explaining the region determining unit according to the second embodiment. FIG. 10 is a diagram for explaining a virtual endoscopic image. FIG. 11 is a diagram for explaining the prior art. FIG. 12 is a diagram for explaining the problems of the prior art.

  Exemplary embodiments of an image processing apparatus and a medical image diagnostic apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments.

  First, the configuration of the image processing apparatus according to the first embodiment will be described. FIG. 1 is a diagram illustrating the configuration of the image processing apparatus according to the first embodiment. As shown in FIG. 1, the image processing apparatus 30 according to the first embodiment is connected to a medical image database 20, and the medical image database 20 is connected to a medical image diagnostic apparatus 10. The medical image database 20 is actually connected to a plurality of medical image diagnostic apparatuses 10.

  The medical image diagnostic apparatus 10 according to the first embodiment is a medical image diagnostic apparatus capable of generating a three-dimensional medical image. Specifically, the medical image diagnostic apparatus 10 is an X-ray CT apparatus capable of generating a three-dimensional X-ray CT image, an MRI apparatus capable of generating a three-dimensional MRI image, and an ultrasonic diagnosis capable of generating a three-dimensional ultrasonic image. Such as a device.

  The medical image database 20 is a database that stores various three-dimensional medical images generated by the medical image diagnostic apparatus 10. Specifically, the medical image database 20 is a database of a PACS (Picture Archiving and Communication System) that is a system that manages data of various medical images, and a database of an electronic medical record system that manages an electronic medical record to which medical images are attached. Etc.

  Here, the image processing apparatus 30 according to the first embodiment acquires a three-dimensional medical image designated by a doctor who is an operator from the medical image database 20, performs image processing on the acquired three-dimensional medical image, and then performs a process for the doctor. Present.

  Specifically, the image processing apparatus 30 according to the first embodiment generates a virtual endoscopy (VE) image by a perspective projection method based on a three-dimensional medical image acquired from the medical image database 20. Then, the image processing apparatus 30 according to the first embodiment generates and displays a composite image in which the generated VE image and the cross-sectional image generated from the three-dimensional medical image that is the generation source of the VE image are combined and displayed. It is an apparatus configured to be able to efficiently perform image diagnosis using an image.

  Hereinafter, image processing performed by the image processing apparatus 30 according to the first embodiment will be described in detail with reference to FIGS. 2 is a diagram for explaining the VE image generation unit, FIG. 3 is a diagram for explaining the cutting position determination unit, and FIG. 4 is a diagram for explaining the composition VE image generation unit. FIG. 5 is a diagram for explaining the MPR image generation unit, FIG. 6 is a diagram for explaining the region determination unit in the first embodiment, and FIG. 7 is a composite image generation unit. It is a figure for demonstrating.

  As illustrated in FIG. 1, the image processing apparatus 30 according to the first embodiment includes an input unit 31, a display unit 32, a three-dimensional image data storage unit 33, a VE image generation unit 34, a cutting position determination unit 35, It has a composition VE image generation unit 36, an MPR image generation unit 37, an area determination unit 38, a composite image generation unit 39, and a display control unit 310.

  The input unit 31 includes a mouse, a keyboard, a microphone, and the like, and is used for inputting various setting information for an operator such as a doctor who interprets a medical image to operate the image processing apparatus 30. Various setting information received by the input unit 31 will be described in detail later.

  The display unit 32 includes a monitor and displays various images under the control of the GUI (Graphical User Interface) for receiving various setting information from the operator via the input unit 31 and the display control unit 310 described later. To do.

  The three-dimensional image data storage unit 33 stores the three-dimensional medical image data acquired from the medical image database 20 by the image processing device 30 as specified by the operator via the input unit 31. In the following, when a three-dimensional X-ray image obtained by imaging the large intestine of a subject on which a contrast medium is administered and carbon dioxide is injected is stored in the three-dimensional image data storage unit 33. Will be described. However, the present invention is applicable even when a three-dimensional MRI image or a three-dimensional ultrasonic image obtained by photographing the large intestine of a subject is stored in the three-dimensional image data storage unit 33. In addition, the present invention can be applied even when a portion other than the large intestine is an imaging region of a subject as long as it is a portion where image diagnosis using a VE image can be performed.

  The VE image generation unit 34 generates a virtual endoscopy (VE) image from the three-dimensional X-ray CT image by a perspective projection method. First, the VE image generation unit 34 extracts a region (air region) having a CT value corresponding to air in the three-dimensional X-ray CT image, for example, by processing using a threshold value. Further, the VE image generation unit 34 receives parameters including the viewpoint position, the line-of-sight direction, and the viewing angle set in the air region from the operator via the input unit 31. By setting such parameters, an effective field of view (FOV: Field Of View) of the VE image is set. Then, the VE image generation unit 34 generates a VE image by perspectively projecting a three-dimensional X-ray CT image radially from a set viewpoint position in a range determined by the viewing direction and the viewing angle.

  For example, when parameters including a viewpoint position, a line-of-sight direction, and a viewing angle as shown in FIG. 2A are set, the VE image generation unit 34 is the same as the core line in the colon lumen from the set viewpoint position. In the direction, a VE image in which the inner wall of the large intestine is observed is generated. When the parameters as shown in FIG. 2B are set, the VE image generation unit 34 causes the inner wall of the large intestine in the viewing direction that is difficult to observe with a normal endoscope from the set viewpoint position. A VE image in which is observed is generated.

  Here, if parameters including the viewpoint position, the line-of-sight direction, and the viewing angle as shown in FIG. 2A are set, the region of interest that the operator wants to observe is the inner wall of the large intestine centering on the core line direction. The whole surroundings. If the parameters as shown in FIG. 2B are set, the region of interest that the operator wants to observe is the inner wall portion of the large intestine located on the lower side of the core line direction with respect to the viewpoint position.

  Returning to FIG. 1, the cutting position determination unit 35 determines a cutting position in which the region of interest determined by the above-described parameters is included in the VE image generated by the VE image generation unit 34. Specifically, the cutting position determination unit 35 determines a cutting position for generating an MPR (Multi Planar Reformat) image to be combined with the VE image. Here, as an initial setting, for example, a “predetermined distance” is set in advance by the operator via the input unit 31, and the cutting position determination unit 35 follows the viewpoint direction from the viewpoint position as shown in FIG. 3. It is determined whether or not the region of interest is included in a cross section orthogonal to the line-of-sight direction (hereinafter referred to as A) at a position advanced by a “predetermined distance”.

  First, the cutting position determination unit 35 refers to the air region extracted from the three-dimensional X-ray CT image by the VE image generation unit 34, and the air region and the non-air region located on the extension line in the line-of-sight direction from the viewpoint position. And the boundary surface is calculated. Here, as shown in FIG. 3, the air region is a region corresponding to the lumen of the large intestine, and the boundary surface between the air region and the non-air region is the most when observed from the viewpoint position along the line-of-sight direction. It is a surface (hereinafter referred to as A ′) where the inner wall of the large intestine exists at a close position.

  Here, when the position of A is closer to the position of A ′ when viewed from the viewpoint position, the cutting position determination unit 35 determines that A is included in the region of interest and determines A determined by the initial setting as the cutting position ( (See (A) of FIG. 3). On the other hand, when the position of A ′ is closer to the position of A when viewed from the viewpoint position, the cutting position determination unit 35 determines that A does not include the region of interest and A ′ includes the region of interest. Then, A ′ is determined as the cutting position (see FIG. 3B).

  Returning to FIG. 1, the composition VE image generation unit 36 selects an area located on the viewpoint position side with respect to the cutting position determined by the cutting position determination unit 35 from the VE image generated by the VE image generation unit 34. A composite VE image is generated by cutting. For example, the composition VE image generation unit 36 determines the cutting position “A” determined by the cutting position determination unit 35 from the VE image generated by the VE image generation unit 34 based on the parameters shown in FIG. 3 (see (A)), a region located on the viewpoint position side is cut to generate a composition VE image as shown in FIG. Further, the composition VE image generation unit 36 determines the cutting position “A ′” determined by the cutting position determination unit 35 from the VE image generated by the VE image generation unit 34 based on the parameters shown in FIG. A composite VE image is generated by cutting a region located on the viewpoint position side with respect to (see FIG. 3B).

  Returning to FIG. 1, the MPR image generation unit 37 generates an MPR image of the three-dimensional X-ray CT image at the cutting position determined by the cutting position determination unit 35. For example, the synthesizing VE image generation unit 36 targets the three-dimensional X-ray CT image used for generating the VE image by the VE image generation unit 34 based on the parameters shown in FIG. An MPR image at the cutting position “A” of the three-dimensional X-ray CT image is generated (see FIG. 5). In addition, the synthesis VE image generation unit 36 sets the three-dimensional X-ray CT image used by the VE image generation unit 34 to generate the VE image based on the parameters shown in FIG. An MPR image at the cutting position “A ′” of the three-dimensional X-ray CT image is generated (see FIG. 5).

  Returning to FIG. 1, the region determination unit 38 determines an air region in which the region of interest is included in the MPR image generated by the MPR image generation unit 37. Specifically, as shown in FIG. 6A, the region determination unit 38 passes through the viewpoint position of the three-dimensional X-ray CT image and is farthest from the viewpoint position on a straight line in the line-of-sight direction. The position of the point “P” in the located air region is calculated. As a result, the region determination unit 38 calculates position information (hereinafter referred to as point sequence information) of a point sequence connecting the viewpoint position and the point “P” as shown in FIG.

  Then, as shown in FIG. 6A, the region determining unit 38 determines the intersection between the calculated point sequence information and the cutting position determined by the cutting position determining unit 35. Then, the region determination unit 38 determines an air region that is included in the cutting position and connected to the determined intersection. Then, the area determination unit 38 determines that the determined area is a non-display area of the MPR image, as illustrated in FIG. That is, the non-display area of the MPR image is an area that the operator wants to observe on the VE image.

  Returning to FIG. 1, the composite image generation unit 39 generates an area corresponding to the “non-display area of the MPR image” in the composite VE image generated by the composite VE image generation unit 36 and the MPR image generation unit 37 generates. In the MPR image, a composite image is generated by combining regions corresponding to regions other than the “MPR image non-display region”. For example, when the VE image is generated with the parameters shown in FIG. 2A, the composite image generation unit 39 includes a region corresponding to the “MPR image non-display region” of the composite VE image shown in FIG. The synthesized image as shown in FIG. 7 is generated by synthesizing the MPR image shown in FIG. 5 with an area corresponding to an area other than the “non-display area of the MPR image”.

  Returning to FIG. 1, the display control unit 310 controls to display the composite image generated by the composite image generation unit 39 on the monitor of the display unit 32. For example, the composite image generation unit 39 controls to display the composite image illustrated in FIG. 7 on the monitor of the display unit 32. Thereby, the doctor who is an image interpreter can refer to the composite image in which only the VE image of the region of interest is combined with the MPR image.

  Next, processing of the image processing apparatus 30 according to the first embodiment will be described with reference to FIG. FIG. 8 is a flowchart for explaining processing of the image processing apparatus according to the first embodiment.

  As shown in FIG. 8, the image processing apparatus 30 according to the first embodiment stores a 3D X-ray CT image to be processed from the medical image database 20 in the 3D image data storage unit 33 (Yes in step S101). Then, it is determined whether various parameters are set by the operator (step S102). Here, as described above, the various parameters set by the operator are the VE image generation parameters including the viewpoint position, the line-of-sight direction, and the viewing angle, and the “predetermined distance” used for setting the initial cutting position. ".

  Then, when various parameters are not set by the operator (No at Step S102), the image processing device 30 according to the first embodiment stands by until various parameters are set. On the other hand, when various parameters are set by the operator (Yes in step S102), the VE image generation unit 34 extracts an air region from the three-dimensional X-ray CT image, and looks from the viewpoint position set in the air region. A VE image is generated by perspectively projecting a three-dimensional X-ray CT image radially over a range determined by the direction and the viewing angle (step S103).

  Then, the cutting position determination unit 35 determines a cutting position based on the set parameters in the three-dimensional X-ray CT image (step S104). That is, the cutting position determination unit 35 sets a cross section orthogonal to the line-of-sight direction as a cutting position (A) at a position advanced by “a predetermined distance” from the viewpoint position along the viewpoint direction in the three-dimensional X-ray CT image. decide.

  After that, the cutting position determination unit 35 determines whether or not the region of interest is included in the cutting position determined in step S104 (step S105). Specifically, the cutting position determination unit 35 refers to the air region extracted from the three-dimensional X-ray CT image by the VE image generation unit 34, and the inner wall of the large intestine located on the extended line in the line-of-sight direction from the viewpoint position The surface (A ′) on which is present is calculated. Then, when the position of A is closer to the position of A ′ when viewed from the viewpoint position, the cutting position determination unit 35 determines that a region of interest is included in A. On the other hand, when the position of A ′ is closer to the position of A when viewed from the viewpoint position, the cutting position determination unit 35 determines that the region of interest is not included in A.

  Here, when it is determined that the region of interest is included in the cutting position (A) determined in step S104 (Yes in step S105), the cutting position determination unit 35 uses the cutting position determined in step S104 as a composition VE. The image generation unit 36 and the MPR image generation unit 37 are notified (step S108).

  On the other hand, when it is determined that the region of interest is not included in the cutting position (A) determined in step S104 (No in step S105), the cutting position determination unit 35 determines a new cutting position (step S106). That is, the cutting position determination unit 35 determines that A ′ includes a region of interest, and determines A ′ as a new cutting position. Then, the cutting position determination unit 35 notifies the combining VE image generation unit 36 and the MPR image generation unit 37 of the cutting position determined in step S106 (step S107).

  Then, the composition VE image generation unit 36 generates a composition VE image from the VE image generated by the VE image generation unit 34 by using the cutting position notified from the cutting position determination unit 35 (step S109). That is, the composition VE image generation unit 36 generates a composition VE image by cutting an area located on the viewpoint position side with respect to the cutting position from the VE image generated by the VE image generation unit 34.

  Subsequently, the MPR image generation unit 37 generates an MPR image from the three-dimensional X-ray CT image using the cutting position notified from the cutting position determination unit 35 (step S110). That is, the MPR image generation unit 37 generates an MPR image of the three-dimensional X-ray CT image at the cutting position determined by the cutting position determination unit 35.

  Then, the region determination unit 38 determines a non-display region of the MPR image by determining an air region including the region of interest in the MPR image generated by the MPR image generation unit 37 (see step S111, FIG. 6). .

  After that, the composite image generation unit 39 combines the region corresponding to the “non-display region of the MPR image” in the composite VE image and the region corresponding to the region other than the “non-display region of the MPR image” in the MPR image. The synthesized image is generated (step S112).

  Then, the display control unit 310 controls to display the composite image generated by the composite image generation unit 39 on the monitor of the display unit 32 (step S113), and ends the process.

  As described above, in the first embodiment, the VE image generation unit 34 determines the 3D X-ray CT image stored in the 3D image data storage unit 33 based on the viewing direction and the viewing angle from the set viewpoint position. A VE image is generated by performing radial projection on the range in a radial manner. Then, the cutting position determination unit 35 determines a cutting position including a region of interest determined by the viewpoint position, the line-of-sight direction, and the viewing angle in the VE image generated by the VE image generation unit 34. Then, the composition VE image generation unit 36 cuts a region located on the viewpoint position side with respect to the cutting position determined by the cutting position determination unit 35 from the VE image generated by the VE image generation unit 34. The composition VE image is generated, and the MPR image generation unit 37 generates an MPR image of the three-dimensional X-ray CT image at the cutting position determined by the cutting position determination unit 35.

  Then, the region determination unit 38 determines an air region that includes the region of interest in the MPR image generated by the MPR image generation unit 37. The composite image generation unit 39 includes an “MPR image” in the region corresponding to the “non-display region of the MPR image” in the composite VE image generated by the composite VE image generation unit 36 and the MPR image generated by the MPR image generation unit 37. A combined image is generated by combining regions corresponding to regions other than “non-display region”. The display control unit 310 performs control so that the composite image generated by the composite image generation unit 39 is displayed on the monitor of the display unit 32.

  Therefore, according to the first embodiment, since only the region of interest to be observed with the VE image is always displayed with the composite image, the image diagnosis using the VE image can be performed efficiently. In particular, it is possible to improve the efficiency of image diagnosis in preoperative diagnosis including screening examination. In addition, according to the first embodiment, since the synthesized image synthesized with the MPR image is displayed except for the region of interest of the VE image, the CT value inside the tissue of the region of interest (the inner wall of the large intestine) can be reliably grasped. Therefore, image diagnosis using a VE image can be performed more efficiently.

  Further, the composite image display method according to the first embodiment is advantageous not only in CTC (CT Colonography) in the X-ray CT apparatus, but also in that the burden on the subject is reduced and the X-ray exposure does not occur compared to the CTC. It can also be executed by MRC (MR Colonography) in the MRI apparatus that has it, and the spread of MRC can be promoted.

  In the second embodiment, a case in which a composite image is sequentially generated and displayed by moving the viewpoint position at “predetermined intervals” along the line-of-sight direction will be described with reference to FIG. FIG. 9 is a diagram for explaining the region determination unit in the second embodiment.

  The image processing apparatus according to the second embodiment has the same configuration as that of the image processing apparatus 30 illustrated in FIG. 1, but the processing content performed by the region determination unit 38 is different from that of the first embodiment. Hereinafter, this will be mainly described.

  Similar to the first embodiment, the region determination unit 38 in the second embodiment determines an air region in which the region of interest is included in the MPR image. However, unlike the first embodiment, the region determination unit 38 in the second embodiment newly uses the air region including the region of interest determined in the MPR image generated immediately before and the “predetermined interval”. An air region that includes a region of interest in the generated MPR image is determined.

  For example, as shown in FIG. 9A, it is assumed that the line-of-sight direction is set as the core of the large intestine, and “movement interval: d” is set as the “predetermined interval”. In such a case, the viewpoint position (i) used when the composite image is generated and displayed immediately before is set to the viewpoint position (i + 1) advanced by “movement interval: d” along the core line direction at the next time point. Will move. Here, the image processing apparatus 30 sequentially uses the viewpoint position (i + 1) to generate a VE image, determine a cutting position, generate a synthesis VE image, and generate an MPR image, as in the first embodiment.

  Then, as shown in FIG. 9B, the region determination unit 38 sets the non-display region (i) of the MPR image determined in the processing of the viewpoint position (i) along the core line direction as “movement interval: d”. The cross section in the same air region as the non-display area (i) is determined as the non-display area (i + 1). Thereby, the image processing device 30 performs the generation and display processing of the composite image at the viewpoint position (i + 1).

  In the processing of the image processing apparatus 30 in the second embodiment, “movement interval: d” is added to the parameter set in step S102 in FIG. Further, the image processing apparatus 30 according to the second embodiment performs the processes of steps S103 to S112 in FIG. 8 in the same manner as the first embodiment at the first viewpoint position. Then, after the second viewpoint position, the image processing apparatus 30 according to the second embodiment performs the process of step S111 among the processes of steps S103 to S112 in FIG. 8 by the process described above.

  As described above, in the second embodiment, when the viewpoint position is moved and the synthesized images are sequentially synthesized and displayed, a new non-display area is determined using the non-display area determined immediately before. It is possible to reduce the processing load when generating.

  In the first and second embodiments, the case where the image processing apparatus 30 is installed independently of the medical image diagnostic apparatus 30 has been described. However, the present invention is not limited to this and the medical image diagnostic apparatus 10 is not limited thereto. The image processing apparatus 30 may be incorporated in the image processing apparatus. That is, the image processing apparatus 30 is incorporated in an X-ray CT apparatus that can generate a three-dimensional X-ray CT image, an MRI apparatus that can generate a three-dimensional MRI image, an ultrasonic diagnostic apparatus that can generate a three-dimensional ultrasonic image, and the like. It may be the case.

  As described above, the image processing apparatus and the medical image diagnostic apparatus according to the present invention are useful when performing virtual endoscopy display, and in particular, efficiently perform image diagnosis using a virtual endoscopic image. Suitable for.

DESCRIPTION OF SYMBOLS 10 Medical image diagnostic apparatus 20 Medical image database 30 Image processing apparatus 31 Input part 32 Display part 33 Three-dimensional image data memory | storage part 34 VE image generation part 35 Cutting position determination part 36 VE image generation part 37 MPR image generation part 38 Area | region Determination unit 39 Composite image generation unit 310 Display control unit

Claims (3)

Projection image generating means for generating a projection image from three-dimensional medical image data by a perspective projection method using setting information including a viewpoint position, a line-of-sight direction, and a viewing angle;
A cutting position determining means for determining a cutting position including a region of interest determined by the setting information in the projection image generated by the projection image generating means;
A first image is generated by cutting an area located on the viewpoint position side with respect to the cutting position determined by the cutting position determining means from the projection image generated by the projection image generating means. An image generating means;
Second image generating means for generating a cross-sectional image of the three-dimensional medical image data at the cutting position determined by the cutting position determining means as a second image;
Area determining means for determining an air area in which the region of interest is included in the second image generated by the second image generating means;
The region corresponding to the air region determined by the region determining unit in the first image and the region corresponding to a region other than the air region determined by the region determining unit in the second image are combined. A composite image generating means for generating the composite image,
Display control means for controlling the composite image generated by the composite image generation means to be displayed on a predetermined display unit;
An image processing apparatus comprising: When the composite image is generated and displayed sequentially by moving the viewpoint position at a predetermined interval along the line-of-sight direction,
The region determination unit determines an air region including the region of interest in the second image newly generated by the second image generation unit based on the air region determined immediately before and the predetermined interval. The image processing apparatus according to claim 1, wherein: Image data collection means for collecting three-dimensional medical image data;
A projection image generating means for generating a projection image from the three-dimensional medical image data collected by the image data collecting means by a perspective projection method using setting information including a viewpoint position, a line-of-sight direction, and a viewing angle;
A cutting position determining means for determining a cutting position including a region of interest determined by the setting information in the projection image generated by the projection image generating means;
A first image is generated by cutting an area located on the viewpoint position side with respect to the cutting position determined by the cutting position determining means from the projection image generated by the projection image generating means. An image generating means;
Second image generating means for generating a cross-sectional image of the three-dimensional medical image data at the cutting position determined by the cutting position determining means as a second image;
Area determining means for determining an air area in which the region of interest is included in the second image generated by the second image generating means;
The region corresponding to the air region determined by the region determining unit in the first image and the region corresponding to a region other than the air region determined by the region determining unit in the second image are combined. A composite image generating means for generating the composite image,
Display control means for controlling the composite image generated by the composite image generation means to be displayed on a predetermined display unit;
A medical image diagnostic apparatus comprising:

Images