JP2008000270A - Biotissue identification image creation method, device and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biotissue identification image creation method, device and program sufficiently supporting a diagnosis by a doctor or the like such as specification of constricted portions in luminal tissue according to types and confirmation of tumorigenesis in the periphery of the luminal tissue. <P>SOLUTION: This biotissue identification image creation method is characterized in performing an observation image creation process (step S1) creating an observation image covering a prescribed range along the longitudinal direction of the specified luminal tissue based on three-dimensional image data in a living body, a search region setting process (step S2) setting a prescribed search region in the observation image using the position of the luminal tissue as a benchmark, and an identification display process (step S3) displaying the specific image region corresponding to a region of interest in the biotissue in the search region so as to identify it from other image regions. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a technique for supporting image diagnosis, and in particular, CT (computed).
tomography, magnetic resonance imaging (MRI), nuclear medicine and other in-vivo 3D image data based on in-vivo three-dimensional image data, attention in or around luminal tissues such as blood vessels, lymphatic vessels, and trachea Observation suitable for supporting diagnosis of a site (for example, a site where neutral fat or cholesterol is attached or calcified in a blood vessel, or a site where a tumor such as a lipoma or cyst is formed around a blood vessel) The present invention relates to a method, apparatus, and program for creating an identification image of a living tissue that can create an image for use.

  In recent years, an image reconstruction technique called CPR (curved planar reconstruction) has been widely used in diagnostic imaging systems. CPR is a technique for reconstructing 3D image data along a specified arbitrary curved surface into a 2D image, and is classified into Projected CPR, Stretched CPR, Straightened CPR, etc., depending on the final image acquisition method. (See pages 380-382 of Non-Patent Document 1 below).

  This CPR method is suitable for collecting and displaying information on a luminal tissue that travels in a living body in a complex manner on a two-dimensional image. In recent years, the CPR method is particularly useful for observing coronary blood vessels and cerebral blood vessels of the heart. It is applied to the creation of images and is used for diagnosis of stenotic sites in blood vessels.

  Conventionally, in order to create a blood vessel observation image using the CPR technique, a core line (center line) extending along the long axis direction of a blood vessel to be observed is specified in advance over the entire observation target region. It is said that there is a need, and various techniques for this have been proposed (see Patent Documents 1 and 2 below).

  In Patent Document 1 below, on each tomographic image obtained by a CT image diagnostic system, two points (start point and end point) located in a blood vessel to be observed are defined as an operator (actual) such as a doctor or an engineer. Describes a technique that can specify the core of a blood vessel in a three-dimensional manner.

  Further, in Patent Document 2 below, an operator designates a point in a blood vessel to be observed on a predetermined image obtained by a CT image diagnostic system, thereby searching for the stretching direction of the core wire. A technique capable of three-dimensionally specifying the core wire is described.

  On the other hand, unlike these methods, a method capable of appropriately creating an image for observation of a luminal tissue even when using three-dimensional image data obtained by an MRI image diagnostic system is disclosed in the present applicant. And disclosed to the Patent Office (see Patent Document 3 below). In this proposed method, an image created to include a route line designated by an operator (actual person) such as a doctor or engineer is sequentially updated in response to a route line correction operation performed by the operator. .

JP 2004-283373 A JP 2004-313736 A Japanese Patent Application No. 2006-171232 Edit Yukio Kuribayashi, Satoshi Sakuma MDCT and MRI for cardiovascular disease

  Any of the methods described in Patent Documents 1 to 3 can be applied to create an image for observation of the coronary blood vessels, cerebral blood vessels, and the like of the heart described above, and obtained by these methods. The observation image is extremely useful when an operator such as a doctor diagnoses the presence or absence of a stenosis site in a blood vessel.

  However, the obtained images for observation can be fully utilized when specifying whether the stenosis part is a part where neutral fat or cholesterol is attached or a calcified part. It is not.

  It is also known that tumors such as lipomas and cysts have a high probability of occurring in the periphery of blood vessels and lymph vessels. Therefore, if it becomes possible to make a diagnosis on a site of interest such as a tumor existing in the peripheral part of a blood vessel using the obtained observation image, the range of utilization of the observation image is further expanded.

  However, the images for observation obtained by the above methods are mainly intended for diagnosis support of stenotic sites in blood vessels, and can easily diagnose the presence of a site of interest such as a tumor around the blood vessels. It is not a thing.

  The present invention has been made in view of the above circumstances, and sufficiently supports diagnosis by a doctor or the like, such as specifying the type of a stenosis site in a tubular tissue or confirming tumor formation in the periphery of the tubular tissue. It is an object to provide a method, apparatus, and program for creating an identification image of a living tissue.

An identification image creation method for a living tissue according to the present invention includes:
An observation image creation process for creating an observation image over a predetermined range along the long axis direction of a specified tubular tissue based on in-vivo three-dimensional image data;
In the observation image, a search area setting process for setting a predetermined search area based on the position of the tubular tissue,
In the search area, an identification display process for displaying a specific image area corresponding to the attention site in the living body so as to be distinguishable from other image areas;
It is characterized by performing.

  In this biological tissue identification image creation method, it is preferable that the specific image region is displayed in a different color for each corresponding type of the region of interest.

The observation image creation process includes
A route image along the route line of the designated portion is received in response to a designation operation from the outside that designates a part of the route line extending along the long axis direction of the tubular tissue shown in the original image. After performing route image display processing to display,
In response to an external correction operation for correcting the route line indicated in the route image, an updated route image display process for displaying the updated route image along the corrected route line is performed at least once. The processing for creating the observation image can be performed.

  The biological tissue identification image creation program according to the present invention is characterized by comprising the steps of causing a computer to execute each process in the biological tissue identification image creation method according to the present invention.

Moreover, the identification image creation apparatus for living tissue according to the present invention is
Comprising image processing means, image display means and operation means;
The image processing means includes
Observation image creation means for creating an observation image over a predetermined range along the long axis direction of the tubular tissue designated via the operation means based on in-vivo three-dimensional image data;
In the observation image, search area setting means for setting a predetermined search area based on the position of the tubular tissue,
In the search area, identification display command means for causing the image display means to display a specific image area corresponding to the target site in the living body so as to be distinguishable from other image areas;
It is characterized by comprising.

In this biological tissue identification image creation device, the observation image creation means includes:
The route of the designated portion in response to a designation operation from the outside via the operation means, which designates a part of a route line extending along the long axis direction of the tubular tissue shown in the original image A route image display command means for displaying a route image along the line on the image display means;
In response to an external correction operation via the operation unit that corrects the route line indicated in the route image, the updated route image along the corrected route line is displayed on the image display unit. And an updated route image display command means for display.

  The above-mentioned “route line” means a curve (including a straight line) extending along the longitudinal direction of the tubular tissue while being located inside the tubular tissue shown on the image. The concept differs from that passing through the central position of the cross-section of the luminal tissue, such as a curve called a core line or a center line. However, the case where the route line corresponds to the core line (center line) is not excluded.

  In the present invention, a predetermined search area is set with reference to the position of the luminal tissue, and in this search area, a target site in the living body (for example, a site where a tumor such as a lipoma is formed). The corresponding specific image area is displayed so as to be distinguishable from other image areas.

  Therefore, it is possible for a doctor or other operator to easily recognize that a tumor or the like may exist in a region in the living body indicated in the observation image. Thus, it is possible to sufficiently support a diagnosis by a doctor or the like such as the occurrence of a stenosis site or the confirmation of tumor formation in the periphery of a tubular tissue.

  In particular, according to what the specific image region is displayed in different colors for each type of the corresponding region of interest, a plurality of types of regions of interest (for example, lipoma, cyst, other It is possible for an operator such as a doctor to easily recognize that there is a possibility that a tumor is present. It is possible to more effectively support diagnosis by a doctor or the like, such as specifying the type of tumor or the like in the peripheral part.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a biological tissue identification image creation apparatus according to an embodiment of the present invention.

  The biological tissue identification image creation device shown in FIG. 1 is designated based on in-vivo three-dimensional image data obtained by an image diagnostic system such as CT, MRI, nuclear medicine, etc., and designated blood vessels, lymph vessels, intestinal tracts, trachea An image for observation over a predetermined range along the long axis direction of a tubular tissue such as an esophageal tube is created, and in this observation image, a specific image region is displayed so as to be distinguishable from other image regions As an operation means composed of an image processing apparatus 1 as an image processing means composed of a computer or the like, an image display apparatus 2 as an image display means having a display screen composed of a liquid crystal panel or the like, and a mouse or a keyboard The operating device 3 is provided.

  The image processing apparatus 1 includes a CPU 11 that performs various arithmetic processes and a storage unit such as a RAM and a ROM, and image data that stores in-vivo three-dimensional image data obtained by an image diagnostic system. A storage unit 12 and a created image storage unit 13 that stores the image-processed image are provided. Also, a created image output interface 14 that outputs an image-processed image to the image display device 2, an operation input interface 15 that transmits various operation inputs from the operation device 3 to the control unit, and a communication or storage medium. And an image data interface 16 for transmitting the in-vivo three-dimensional image data input to the control unit 11.

  The storage device in the control unit 11 stores an identification image creation program for living tissue according to an embodiment of the present invention for causing the image processing apparatus 1 to execute each process described later. The controller 11 that executes the identification image creation program constitutes the observation image creation means, search area setting means, identification display command means, route image display command means, and updated route image display command means in the apparatus of the present embodiment. ing.

  Next, a method for creating an identification image of a living tissue according to the present invention will be described. 2-6 is a figure which shows the procedure of the identification image creation method of the biological tissue which concerns on one Embodiment of this invention. FIG. 2 is a flowchart of the identification image creation process, and FIG. 3 is a flowchart of the observation image creation process shown in FIG. 4 is a flowchart of the route image display process shown in FIG. 3, FIG. 5 is a flowchart of the changed route image display process shown in FIGS. 4 and 6, and FIG. 6 is a flowchart of the updated route image display process shown in FIG. It is. The biological tissue identification image creation method according to the present embodiment is performed using the biological tissue identification image creation apparatus shown in FIG.

  In the identification image creation process shown in FIG. 2, first, an observation image for creating an observation image within a predetermined range along the long axis direction of a specified tubular tissue based on in-vivo three-dimensional image data. Creation processing is performed (step S1 in FIG. 2).

  In this observation image creation process, as shown in FIG. 3, designation from the outside (by the operator) that designates a part of the route line extending along the long axis direction of the tubular tissue shown in the original image In response to the operation, a route image display process for displaying a route image along the route line of the designated portion is performed (step S10 in FIG. 3), and then from the outside for correcting the route line indicated in the route image. In response to the correction operation (by the operator), an updated route image display process for displaying the updated route image along the corrected route line is performed (step S20 in FIG. 3). This updated route image display process is normally repeated a plurality of times until an instruction is given from the operator to use the displayed updated route image as an observation image (step S30 in FIG. 3).

  The route image display process is performed according to the procedure shown in FIG. 4, and the updated route image display process is performed according to the procedure shown in FIG. Further, the post-change route image display process shown in FIGS. 4 and 6 is performed according to the procedure shown in FIG. 4 to 6 are the same as FIGS. 3 to 5 described in Patent Document 3 described above. The specific contents of each process shown in these drawings are the same as those described in the above-mentioned Patent Document 3, and detailed description thereof is omitted in this specification.

  The observation image obtained by the observation image creation process is displayed on the screen of the image display device 2 (see FIG. 1). FIG. 7 shows a display example of an observation image. In this display example, three types of images, a stretched CPR image 26, a straightened CPR image 27, and a cross-sectional image 28, are displayed on the screen of the image display device 2. It is like that. The stretched CPR image 26 is an image in a state in which the path curved surface set by the path curved surface setting process (step S13 in FIG. 4) shown in FIG. 4 is extended to a plane. The image is reconstructed so that 23 is a straight line. The cross-sectional image 28 is an image along a cross-section orthogonal to the route line 23 at a predetermined position in the long axis direction of the tubular tissue 21 shown in the Stretched CPR image 26.

  In the Stretched CPR image 26 and the Straightened CPR image 27, the luminal tissue 21 (coronary blood vessel of the heart) located on the path curved surface is set by the path line display process shown in FIG. 4 (step S12 in FIG. 4). 23 (see the above-mentioned Patent Document 3 for details). In the cross-sectional image 28, a linear inclined line 32 indicating the inclination of the path curved surface extended in a plane is displayed together with the tubular tissue 21. The inclination line 32 can be changed on the screen by the operator using the operation device 3 (see FIG. 1). When the inclination of the inclination line 32 is changed, FIG. The same process as the path curved surface direction changing process (step S41 in FIG. 5) shown in FIG. 5 is performed, whereby the observation direction of the luminal tissue 21 can be changed. In FIG. 7, for the sake of simplification, illustration of biological tissues other than the tubular tissue 21 is omitted.

  After the observation image creation process, a search area setting process is performed (step S2 in FIG. 2). This search area setting process is a process for setting a predetermined search area based on the position of the luminal tissue 21 in the observation image (Stretched CPR image 26 or Straightened CPR image 27 shown in FIG. 7). In the form, it is performed as follows. FIG. 8 is a diagram showing an example of setting a search area.

  That is, in the example shown in FIG. 8, in the Straightened CPR image 27, the search area 40 is set as a rectangular internal area indicated by a two-dot chain line in the figure. Although the size and position of the search area 40 can be arbitrarily set, in this example, the length of the search area 40 in the left-right direction in the drawing matches the length of the route line 23 and the left-right direction. Are set so as to coincide with the positions of the start point SP and the end point EP of the route line 23. Further, both end positions of the search area 40 in the vertical direction in the figure are equal distances from each other in the vertical direction from the position of the route line 23 (for example, constant within a numerical range of 10 to 20 mm when converted into actual dimensions in the human body). ) Distance).

  The size and position of the search area 40 are automatically set according to a program stored in advance by the control unit 11 (see FIG. 1) when the Straightened CPR image 27 as the observation image is displayed. However, the operation device 3 (see FIG. 1) can be used to allow the operator to instruct the setting of the size and position of the search area 40.

  Subsequent to the search area setting process, an identification display process is performed (step S3 in FIG. 2). This identification display process is a process of displaying a specific image area corresponding to the target site in the living body in the search area 40 so as to be distinguishable from other image areas. In this embodiment, the identification display process is performed as follows. Is called. 9 and 10 are diagrams schematically showing an example of an image in which a specific image region is identified and displayed, and FIG. 9 is a diagram showing an example in which the specific image region is displayed inside the tubular tissue 21. Reference numeral 10 denotes an example in which a specific image region is displayed in the peripheral part of the tubular tissue 21.

  First, it is determined in advance what site is the target site in and around the tubular tissue 21 that is a coronary blood vessel. In the present embodiment, in the tubular tissue 21, a site where (neutral) fat is attached, a site where cholesterol is attached, and a site where calcification is attached are considered as sites of interest. In the periphery of the tubular tissue 21, a site where a lipoma is formed, a site where a cyst is formed, and two other types of tumors (hereinafter referred to as “tumor A”, “tumor” for convenience) Each of the regions where “B” is formed is a region of interest.

Next, the search area 40 is searched for whether or not there is a specific image area corresponding to each region of interest. Whether or not a predetermined area in the search area 40 corresponds to the specific image area is determined based on whether or not the predetermined condition satisfies a predetermined determination condition. As this determination condition, for example, the image density value (including the CT value, MRI signal intensity value, etc.) in the region is within the image density value range shown when each of the target sites is imaged. And that region has a predetermined size (for example, a size of 1 mm ^{2 to 3} cm ² when converted to an actual size).

  Note that the image density value range is determined in advance for each type of target region. As a determination method, when a CT value is used as an image density value, a range of CT values set for each type of attention site can be used as the image density value range. In addition, when a site where fat exists is a target site, ROI (Region of interest) is set in a portion where fat is known to exist in a living body (human body), and measurement is performed. It is also possible to calculate in advance the standard deviation, etc., and use the calculation result for discrimination of the specific image area. In addition, when information such as individual differences between living organisms is obtained in advance, the image density value range can be corrected based on the individual difference information.

  If it is determined by the search that a specific image area exists, the specific image area is displayed so as to be distinguishable from other image areas. In addition, when there are a plurality of specific image areas having different types of corresponding attention parts, the specific image areas are displayed in different colors. In the example shown in FIG. 9, each corresponds to a site where (neutral) fat is attached, a site where cholesterol is attached, and a site where calcification is present in the lumenal tissue 21 which is a coronary blood vessel. The specific image areas 41, 42, and 43 to be displayed are displayed in different colors (for example, red, blue, and yellow). On the other hand, in the example shown in FIG. 10, a site where a lipoma is formed, a site where a cyst is formed, a site where a tumor A is formed, and a tumor B are formed in the periphery of the tubular tissue 21. The specific image areas 44, 45, 46 and 47 corresponding to the portions are displayed in different colors (for example, scarlet, green, indigo and brown). Note that image regions other than the specific image regions 41 to 47 are displayed without being colored.

  An operator such as a doctor looks at the observation image shown in FIG. 9, so that the part where the fat is attached, the part where the cholesterol is attached, and the part where the cholesterol is attached inside the tubular tissue 21 However, it is possible to easily recognize that each of them may exist. Further, by looking at the observation image shown in FIG. 10, a site where a lipoma is formed, a site where a cyst is formed, and another tumor A are formed in the periphery of the tubular tissue 21. It becomes possible to easily recognize that there is a possibility that a part and a part where another tumor B is formed are present.

  The observation images shown in FIGS. 9 and 10 are the Straightened CPR image 27 shown in FIG. 8, and only the image information located on the path curved surface is shown there. Therefore, when the inside and the peripheral part of the tubular tissue 21 are searched three-dimensionally, even if there is a region of interest, on the specific observation image carrying only two-dimensional image information. In some cases, the specific image area is not displayed. In the present embodiment, as described above, an operator such as a doctor can change the inclination of the inclination line 32 shown on the cross-sectional image 28 of FIG. 8 using the operation device 3 (see FIG. 1). This is configured so that when the inclination of the inclined line 32 is changed, the process of changing the direction of the path curved surface is performed. When the direction of the path curved surface is changed, the image information carried in the observation image is changed, so even if the specific image area is not displayed before the direction change of the path curved surface, the direction of the path curved surface is changed. The specific image area may be displayed. That is, in this embodiment, it is possible to search the inside and the peripheral part of the tubular tissue 21 three-dimensionally by changing the direction of the path curved surface.

As described above, in the present embodiment, the search area 40 is set two-dimensionally in the Straightened CPR image 27 shown in FIG. 8, but it may be configured so as to be set three-dimensionally. FIG. 11 shows an example in which the search area is set three-dimensionally. That is, in the example shown in FIG. 11, after specifying the position of the route line 23 in the three-dimensional space, a predetermined area (for example, an actual dimension) that is orthogonal to the route line 23 and centered on the position of the route line 23 is used. A spatial region composed of a plane group (a constant area within a numerical range of 3 to 5 cm ² in terms of 3) (a circle group, only part of which is shown in FIG. 11) 48 is a search region 40A (indicated by a two-dot chain line in the figure) ) Is set.

  In this case, in the search area 40A, a three-dimensional search is performed to determine whether or not a specific image area corresponding to the target site exists. If there is a path curved surface that passes through the specific image area is set. Then, an image for observation (Stretched CPR image 26 or Straightened CPR image 27) carrying image information located on the path curved surface can be created and displayed. The specific image region is displayed in a color-coded manner on the displayed observation image, as in the above-described embodiment.

  In addition, when the method for searching for a specific image region in three dimensions is employed, a 3D image created using a volume rendering (VR) method can be used as the observation image. Such a technique can also be applied to the methods described in the above-mentioned Patent Documents 1 and 2 that three-dimensionally specify the position of the core line (center line) of the tubular tissue. .

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, A mode can be variously changed.

  For example, in the above-described embodiment, an example in which the coronary blood vessel of the heart is a luminal tissue is described. The present invention can be applied even in the case of a textured structure.

  The present invention is useful when using three-dimensional image data obtained by a CT or MRI image diagnostic system, but is also applicable when using image data obtained by another image diagnostic system such as nuclear medicine. Is possible.

The block diagram of the identification image creation apparatus of the biological tissue which concerns on one Embodiment of this invention. Flow chart of identification image creation processing Flowchart of observation image creation processing Flowchart of route image display processing Flowchart of post-change route image display processing Flowchart of updated route image display processing Figure showing a display example of an image for observation Diagram showing search area setting example The figure which shows an example of the image by which the specific image area was identified and displayed The figure which shows the other example of the image by which the specific image area was identified and displayed The figure which shows the example which sets a search area | region in three dimensions

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image processing apparatus 2 Image display apparatus 3 Operation apparatus 11 Control part 12 Image data memory | storage part 13 Created image memory | storage part 14 Created image output interface 15 Operation input interface 16 Image data interface 21 Luminous structure | tissue 23 Path line 26 Stretched CPR image 27 StraightenedCPR Image 28 Cross-sectional image 32 Inclined line 40, 40A Search area 41-47 Specific image area 48 Plane group SP (path line) start point EP (path line) end point

Claims (6)

An observation image creation process for creating an observation image over a predetermined range along the long axis direction of a specified tubular tissue based on in-vivo three-dimensional image data;
In the observation image, a search area setting process for setting a predetermined search area based on the position of the tubular tissue,
In the search area, an identification display process for displaying a specific image area corresponding to the attention site in the living body so as to be distinguishable from other image areas;
A method for creating an identification image of a living tissue, characterized in that:   The method of claim 1, wherein the specific image area is displayed in a different color for each type of the target region of interest. The observation image creation process includes:
A route image along the route line of the designated portion is received in response to a designation operation from the outside that designates a part of the route line extending along the long axis direction of the tubular tissue shown in the original image. After performing route image display processing to display,
In response to an external correction operation for correcting the route line indicated in the route image, an updated route image display process for displaying the updated route image along the corrected route line is performed at least once. ,
The method for creating an identification image of a living tissue according to claim 1 or 2, wherein the image for observation is created.   A biological tissue identification image creation program comprising the steps of causing a computer to execute each process in the biological tissue identification image creation method according to any one of claims 1 to 3. Comprising image processing means, image display means and operation means;
The image processing means includes
Observation image creation means for creating an observation image over a predetermined range along the long axis direction of the tubular tissue designated via the operation means based on in-vivo three-dimensional image data;
In the observation image, search area setting means for setting a predetermined search area based on the position of the tubular tissue,
In the search area, identification display command means for causing the image display means to display a specific image area corresponding to the target site in the living body so as to be distinguishable from other image areas;
An apparatus for creating an identification image of a living tissue, comprising: The observation image creation means includes:
The route of the designated portion in response to a designation operation from the outside via the operation means, which designates a part of a route line extending along the long axis direction of the tubular tissue shown in the original image A route image display command means for displaying a route image along the line on the image display means;
In response to an external correction operation via the operation unit that corrects the route line indicated in the route image, the updated route image along the corrected route line is displayed on the image display unit. Updated route image display command means for displaying; and
The biological tissue identification image creation device according to claim 5, comprising:

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