JP2008148858A - Three-dimensional image processor and medical image diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional image processor capable of displaying blood flow information of blood flowing inside a blood vessel together with stereoscopic display of the inside of the blood vessel, and a medical image diagnostic apparatus provided with such a three-dimensional image processor. <P>SOLUTION: Three-dimensional image data including the surface shape data of the blood vessel of an object are constructed from two or more pieces of tomographic image data relating to the object part of the object in an image gathering part 10, and an image when viewing the three-dimensional image data from a view point position determined inside the blood vessel is generated as a virtual endoscopic image in a virtual endoscopic image generation part 31. Further, the virtual endoscopic image and blood flow information gathered in a blood flow information gathering part 20 are combined in a composition part 32 and displayed at a display part 50. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a three-dimensional image processing apparatus that performs image processing of a medical image and a medical image diagnostic apparatus including the same, and in particular, a three-dimensional view when viewing three-dimensional image data inside a blood vessel of a subject from a viewpoint position determined inside the blood vessel. The present invention relates to a three-dimensional image processing apparatus that creates and displays an image and a medical image diagnostic apparatus including the same.

  Conventionally, three-dimensional image data is constructed from two-dimensional tomographic image (slice image) data such as an X-ray CT image and MR image generated by a medical examination for a subject, and this is stereoscopically displayed on a two-dimensional screen. Thus, a three-dimensional image display device that can observe the shape, size, and the like of each organ in the human body from the outside of each organ is known.

In such a three-dimensional image display device, an organ such as a blood vessel or stomach having a hollow inside is targeted, a viewpoint is placed inside the blood vessel or organ, and a three-dimensional image is constructed along the line of sight determined by the viewpoint. Then, a virtual endoscopic display that enables observation of the inside of a blood vessel or an organ by stereoscopically displaying it on a two-dimensional screen like an endoscopic image observed with an electronic endoscopic device is, for example, It is known in Patent Document 1.
JP 9-139339 A

  Here, in the virtual endoscope display as described above, it is possible to display a stereoscopic image inside the blood vessel, but in order to facilitate detection of an abnormality inside the blood vessel, while viewing the stereoscopic image, There is a desire to instantaneously know a portion where blood flowing inside the blood vessel is flowing backward or a portion where the blood flow velocity is slow, such as a stenotic region.

  The present invention has been made in view of the above circumstances, and includes a three-dimensional image processing apparatus capable of displaying blood flow information of blood flowing in a blood vessel together with a three-dimensional display inside the blood vessel, and such a three-dimensional image processing apparatus. Another object of the present invention is to provide a medical image diagnostic apparatus.

  To achieve the above object, a three-dimensional image processing apparatus according to claim 1 of the present invention includes three-dimensional image data including surface shape data of a blood vessel of a subject from a plurality of tomographic image data relating to the subject portion of the subject. A three-dimensional image display means for displaying the constructed three-dimensional image data as a three-dimensional image inside the blood vessel when viewed from the viewpoint position determined inside the blood vessel, and a three-dimensional image inside the blood vessel, And combining means for synthesizing blood flow information of blood flowing inside the blood vessel displayed as a stereoscopic image and displaying it on the three-dimensional image display means.

  In order to achieve the above object, a medical image diagnostic apparatus according to claim 6 of the present invention collects a plurality of tomographic image data relating to a target region of a subject, and the blood vessels of the subject from the collected tomographic images. Three-dimensional image data construction means for constructing three-dimensional image data including the surface shape data of the three-dimensional image, and a three-dimensional image displayed as a three-dimensional image inside the blood vessel when the three-dimensional image data is viewed from a viewpoint position determined inside the blood vessel. Image display means, blood flow information collection means for collecting blood flow information of blood flowing inside the blood vessel displayed as the stereoscopic image, and the collected blood flow information combined with the stereoscopic image inside the blood vessel. And combining means for displaying on the three-dimensional image display means.

  According to the present invention, there are provided a three-dimensional image processing apparatus capable of displaying blood flow information of blood flowing in a blood vessel together with a three-dimensional display inside the blood vessel, and a medical image diagnostic apparatus including such a three-dimensional image processing apparatus. Can do.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a medical image diagnostic apparatus according to an embodiment of the present invention. The medical image diagnostic apparatus shown in FIG. 1 includes an image collection unit 10, a blood flow information collection unit 20, an image processing unit 30, an input unit 40, and a display unit 50. Here, the medical image diagnostic apparatus illustrated in FIG. 1 is not particularly limited, and examples thereof include a medical image diagnostic apparatus capable of capturing a tomographic image of a subject such as an X-ray CT apparatus and an MRI apparatus.

  As shown in FIG. 1, an electrocardiograph 11 is connected to the image collection unit 10. The electrocardiograph 11 detects a weak current generated by the contraction of the heart of the subject, and outputs the time change of the detected current to the image collecting unit 10 as an electrocardiographic waveform. The image collection unit 10 operates based on the electrocardiographic waveform information of the electrocardiograph 11, images the inside of the subject, collects a plurality of pieces of tomographic image data such as X-ray CT images and MR images, and collects them. Three-dimensional image data (volume data) including the surface shape data of the organs and blood vessels of the subject is constructed by interpolation processing from a plurality of tomographic image data. Then, the constructed three-dimensional image data is output to the virtual endoscopic image generation unit 31 of the image processing unit 30 in association with the electrocardiographic waveform information. The image collection by the image collection unit 10 can be performed by, for example, an X-ray CT apparatus or an MRI apparatus.

  Note that, in order to display the organ lumen in the virtual endoscope, if necessary, the image collection unit 10 may delete a part of the image that hinders the virtual endoscope display by the segmentation technique.

  An electrocardiograph 21 is connected to the blood flow information collection unit 20. The blood flow information collection unit 20 collects blood flow information (blood flow velocity, blood flow direction, and the like) of the subject based on the electrocardiographic waveform information output from the electrocardiograph 21, and a virtual to be described later. In order to associate endoscopic images with blood flow information, tomographic images of the subject are collected to construct 3D image data, and electrocardiographic waveform information, blood flow information, and 3D image data are associated. At the same time, the data is output to the combining unit 32 of the image processing unit 30. Here, the collection of blood flow information by the blood flow information collection unit 20 may be performed using, for example, an ultrasonic Doppler effect, or MR blood flow measurement in an MRI apparatus may be used. Or you may make it collect blood flow information from the dynamics of the contrast part at the time of contrast agent injection | pouring in an X-ray CT apparatus. That is, the blood flow information collection unit 20 is not particularly limited as long as it can collect the three-dimensional image data and blood flow information of the subject.

The image processing unit 30 includes a virtual endoscopic image generation unit 31 and a synthesis unit 32.
The virtual endoscopic image generation unit 31 generates three-dimensional image data (virtual endoscopic image data) when an organ lumen specified by a user such as a doctor is viewed from a viewpoint position specified by the user. . That is, the virtual endoscopic image generation unit 31 stores organ characteristics such as the position, size, threshold value, edge, and pixel value of an organ according to the type of medical image such as an X-ray CT image or an MR image. Based on the distribution statistics and the like, the organ lumen designated by the user is extracted as a binarized image from the volume data obtained by the image collection unit 10. Further, based on the binarized image data, the original three-dimensional image data, and information on the viewing angle, the viewpoint position, and the line-of-sight direction in the virtual endoscope display input from the input unit 40, Endoscopic image data is created, and this virtual endoscopic image data is output to the synthesis unit 32 together with the electrocardiographic waveform information.

  The synthesizing unit 32 displays the blood flow information display image for displaying the blood flow information collected by the blood flow information collecting unit 20 on the virtual endoscope image data generated by the virtual endoscope image generating unit 31 so as to be visible. The data is synthesized and output to the display unit 50.

  The input unit 40 is an operation unit such as a mouse for a user such as a doctor to perform various input operations of the medical image diagnostic apparatus. The display unit 50 is a display unit such as a liquid crystal display that displays the virtual endoscopic image synthesized by the synthesis unit 32 on a two-dimensional screen.

  The operation of the medical image diagnostic apparatus according to this embodiment will be described below. FIG. 2 is a flowchart showing main operations of the medical image diagnostic apparatus according to the present embodiment.

  First, a subject is imaged by the image acquisition unit 10 in synchronization with the operation of the electrocardiograph 11, and three-dimensional image data (including surface shape data of the organ and blood vessels of the subject subject) is acquired from the tomographic images collected thereby. Volume data) is obtained (step S1). In addition, blood flow information and three-dimensional image data (volume data) of the subject are obtained by the blood flow information collection unit 20 in synchronization with the operation of the electrocardiograph 21 (step S2). Thereafter, the three-dimensional image data obtained by the image collecting unit 10 is input to the image processing unit 30 in association with the electrocardiographic waveform information, and the three-dimensional image data and the blood flow obtained by the blood flow information collecting unit 20 Information is input to the image processing unit 30 in association with the electrocardiographic waveform information (step S3). Here, the collection of the three-dimensional image data in the image collection unit 10 and the collection of the three-dimensional image data and the blood flow information in the blood flow information collection unit 20 may be performed simultaneously or separately.

  Subsequently, a user such as a doctor designates the position of the organ lumen to be displayed in the virtual endoscope, the viewing angle, the viewpoint position, and the line-of-sight direction in the virtual endoscope display (step S4). At this time, the MPR3 cross-sectional image or volume rendering image of the organ designated by the user is generated from the three-dimensional image data obtained by the image collecting unit 10, and the viewing angle in a state where these images are displayed on the display unit 50, You may enable it to designate a viewpoint position and a gaze direction.

  When the above various data inputs are completed, a virtual endoscopic image is generated in the virtual endoscopic image generating unit 31 of the image processing unit 30 (step S5). Note that the opacity and color of the virtual endoscope image generated in step S5 may be fixed, but may be set freely by the user.

  After the virtual endoscopic image is generated, the combining unit 32 combines a blood flow information display image for displaying blood flow information so as to be visible on the virtual endoscopic image (step S6). Then, the virtual endoscopic image obtained by combining the blood flow information display image is displayed on the display unit 50 as shown in FIG. 3, for example (step S7). Here, reference numeral 51 a in FIG. 3 is a blood flow information display image showing the blood flow direction at the viewpoint position 52, and 51 b is a blood flow information display image showing the blood flow velocity at the viewpoint position 52. That is, in the example of FIG. 3, at the viewpoint position 52, the blood flow direction is from the front to the back of the drawing, and the blood flow velocity is 300 ml / s (20 cm / s). The display position of the blood flow information display image and the display form of the blood flow information display image are not limited to those shown in FIG. For example, when inputting the viewpoint position or the like in step S4, one or more pieces of information on the position where blood flow information is to be displayed can be input, and the blood flow information corresponding to the position is represented by, for example, the reference symbol in FIG. You may make it display as shown to 53,54. Further, the blood flow may be indicated by a three-dimensional arrow image as indicated by reference numeral 55 in FIG. 4 so that the three-dimensional blood flow can be easily seen.

  In addition, the viewpoint position and the line-of-sight direction can be changed by the user's operation of the input unit 40 in the virtual endoscopic image displayed as shown in FIGS. 3 and 4. In this case, the processing after step S5 in FIG. 2 may be performed again based on the changed viewpoint position and line-of-sight direction. Further, if the input unit 40 is an operation member such as a wheel mouse, it is possible to move the viewpoint position of the virtual endoscopic image as the wheel rotates. In this case, if the moving speed of the viewpoint position is changed in accordance with the blood flow velocity and the blood flow direction, it is possible to give a visual effect as if the user is traveling in the blood flow.

  Furthermore, the virtual endoscopic image on the display unit 50 is not limited to a simple three-dimensional image, and may be a four-dimensional image that displays a three-dimensional image in time series. In this case, a new virtual endoscopic image may be sequentially generated as time changes, and a blood flow information display image may be synthesized and displayed on the generated virtual endoscopic image.

  Next, the composition process in step S6 will be further described. FIG. 5 is a flowchart showing the composition process in the composition unit 32.

  In the synthesis process, first, the time alignment between the three-dimensional image data (virtual endoscope image) generated by the virtual endoscope image generation unit 31 and the three-dimensional image data input from the blood flow information collection unit 20 is performed. Is performed (step S11). That is, in the three-dimensional image data input from the blood flow information collection unit 20 from the electrocardiogram waveform information of the electrocardiograph 11 and the electrocardiogram waveform information of the electrocardiograph 21, the virtual endoscope image generation unit 31. Three-dimensional image data collected at the same phase timing on the electrocardiogram waveform and the generated virtual endoscope image data is selected. Next, the 3D image data generated in the virtual endoscope image generating unit 31 and the 3D image data selected in step S11 are aligned (step S12).

  For example, when the three-dimensional image collected by the image collection unit 10 is an X-ray CT image and the blood flow information collected by the blood flow information collection unit 20 is information obtained from an ultrasonic Doppler image, usually, Since the coordinate systems when the two are collected do not match, it is necessary to perform the alignment shown in step S12. This alignment is performed by, for example, matching the coordinate system of the image collecting unit 10 with the feature point matching between the three-dimensional image data obtained by the image collecting unit 10 and the three-dimensional image data obtained by the blood flow information collecting unit 20. If image space position correction data (for example, a conversion matrix for converting the coordinate system of the image collection unit 10 into the coordinate system of the blood flow information collection unit 20) for matching with the coordinate system of the flow information collection unit 20 is obtained. good. By such alignment, one point on the space in the three-dimensional image data collected by the image collecting unit 10 and the three-dimensional image data collected by the blood flow information collecting unit 20 showing the same coordinate value as this point. One point on the space indicates the same position of the subject.

  In step S12, after the image space position correction data is obtained, blood flow information corresponding to the viewpoint position designated by the user is selected (step S13). Thereafter, blood flow information display image data for displaying the blood flow information in a visually recognizable manner (for example, an index image for indicating the blood flow direction and a character image for indicating the blood flow velocity) is generated and generated. The blood flow information display image data and the virtual endoscope image data are synthesized as shown in FIGS. 3 and 4 (step S14).

  As described above, according to the present embodiment, the blood flow information is displayed so as to be visible when the virtual endoscopic image is displayed, so that the user can view the blood flow information such as the blood flow direction and the blood flow velocity. It is possible to confirm while looking at the mirror image.

  Although the present invention has been described based on the above embodiments, the present invention is not limited to the above-described embodiments, and various modifications and applications are naturally possible within the scope of the gist of the present invention.

  Further, the above-described embodiments include various stages of the invention, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some configuration requirements are deleted from all the configuration requirements shown in the embodiment, the above-described problem can be solved, and this configuration requirement is deleted when the above-described effects can be obtained. The configuration can also be extracted as an invention.

It is a block diagram which shows the structure of the medical image diagnostic apparatus which concerns on one Embodiment of this invention. It is a flowchart shown about main operation | movement of a medical image diagnostic apparatus. It is a 1st display example of a virtual endoscopic image and a blood flow information display image. It is a 2nd display example of a virtual endoscopic image and a blood flow information display image. It is a flowchart shown about the synthetic | combination process in a synthetic | combination part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Image collection part, 11 ... Electrocardiograph, 20 ... Blood flow information collection part, 21 ... Electrocardiograph, 30 ... Image processing part, 31 ... Virtual endoscopic image generation part, 32 ... Synthesis part, 40 ... Input 50, display unit

Claims (6)

The three-dimensional image data including the surface shape data of the blood vessel of the subject is constructed from a plurality of tomographic image data related to the target region of the subject, and the constructed three-dimensional image data is viewed from a viewpoint position determined inside the blood vessel. 3D image display means for displaying as a stereoscopic image inside the blood vessel at the time,
Synthesis means for synthesizing blood flow information of blood flowing inside the blood vessel displayed as the stereoscopic image with the stereoscopic image inside the blood vessel and displaying the information on the three-dimensional image display means;
A three-dimensional image processing apparatus comprising:   The three-dimensional image processing apparatus according to claim 1, wherein the display position of the blood flow information is a viewpoint position determined inside the blood vessel. Further comprising position specifying means for specifying the position of at least one point in the stereoscopic image inside the blood vessel;
The three-dimensional image processing apparatus according to claim 1, wherein the display position of the blood flow information is a position specified by the position specifying means.   The said synthetic | combination means synthesize | combines the parameter | index which shows the blood flow direction which shows the direction of the blood flow in the three-dimensional image inside the said blood vessel as the said blood flow information three-dimensionally. 3D image processing device.   The three-dimensional image display means, based on a plurality of tomographic image data relating to a target region of a subject input in time series, a stereoscopic image inside the blood vessel when viewed from the viewpoint position determined in the blood vessel in time series. The three-dimensional image processing apparatus according to claim 1, wherein the three-dimensional image processing apparatus is displayed. Three-dimensional image data construction means for collecting a plurality of tomographic image data relating to a target region of a subject and constructing three-dimensional image data including surface shape data of the blood vessels of the subject from the collected tomographic images;
3D image display means for displaying the 3D image data as a stereoscopic image inside the blood vessel when viewed from a viewpoint position determined inside the blood vessel;
Blood flow information collecting means for collecting blood flow information of blood flowing inside the blood vessel displayed as the stereoscopic image;
Synthesis means for synthesizing the collected blood flow information with the stereoscopic image inside the blood vessel and displaying it on the three-dimensional image display means;
A medical image diagnostic apparatus comprising:

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