JP2010137004A - Radiation image processing system and processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiation image processing system easily selecting corresponding specified regions from two pairs of radiation images obtained by radiographing a subject from two different directions, and correctly finding positions of the specified regions, and to provide a processing method. <P>SOLUTION: The radiation image processing system includes: a radiographing part 30 for radiographing the subject 28 from the two different directions and obtaining the two pairs of radiation images; a display part 78 for displaying the two pairs of radiation images; a selecting part 80 for selecting the specified regions from the respective two radiation images displayed in the display part 78; and a range calculating part 84 for calculating the specified range of one radiation image which includes the specified region selected from the other radiation image displayed in the display part 78. The display part 78 displays the calculated specified range in the one radiation image. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a radiographic image processing system and a processing method for obtaining the position of a specific part included in a radiographic image from a plurality of sets of radiographic images obtained by photographing subjects from a plurality of different directions.

  For example, a biopsy device has been developed for the purpose of collecting a tissue of a lesion site and performing a precise examination for disease diagnosis or the like (see Patent Document 1). In this case, in order to accurately collect a specific tissue, it is necessary to determine the position of the tissue in advance. Patent Document 1 discloses that the position of a specific part is calculated using two sets of radiographic images obtained by photographing a subject from two different directions.

JP 10-201749 A

  Here, in order to calculate the position of the specific part, it is necessary to select the same specific part from each of the two sets of radiation images. FIG. 8 shows a display example of the acquired two sets of radiation images 2L and 2R. Each radiation image 2L, 2R has a plurality of specific parts 4L, 6L and 4R, 6R, respectively, and the specific parts 4L and 4R and 6L and 6R correspond to each other.

  The operator confirms the displayed radiographic images 2L and 2R, and selects the same specific parts 4L and 4R or 6L and 6R from the radiographic images 2L and 2R. In this case, for example, if the specific parts 4L and 4R are selected, the three-dimensional positions of the specific parts 4L and 4R can be correctly calculated. However, since there are many such specific parts 4L, 6L and 4R, 6R on the radiographic images 2L, 2R, there is a possibility that the specific parts 4L and 6R may be selected by mistake, for example. In this case, the position of the desired specific part cannot be calculated correctly.

  The present invention has been made to solve the above-described problems, and easily selects a corresponding specific part from two sets of radiographic images obtained by photographing a subject from a plurality of different directions, and the specific part. An object of the present invention is to provide a radiation image processing system and a processing method that can accurately determine the position of the image.

The radiographic image processing system of the present invention, an imaging unit that captures a subject from a plurality of different directions and acquires a plurality of sets of radiographic images,
A display unit for displaying a plurality of sets of the radiation images;
A selection unit that selects a specific part from each of two predetermined sets of radiographic images among the plurality of sets of radiographic images displayed on the display unit;
A range calculation unit for calculating a specific range of the other radiographic image including the specific part selected from the one radiographic image;
The display unit displays the calculated specific range on the other radiation image.

Further, the radiographic image processing method of the present invention is a step of photographing a subject from a plurality of different directions and acquiring a plurality of sets of radiographic images;
Displaying a plurality of sets of the radiation images;
Selecting a specific part from one of the predetermined two sets of the radiographic images among the plurality of displayed radiographic images;
Obtaining a specific range including the selected specific part from the other radiographic image;
Displaying the specific range on the other radiographic image;
Selecting the specific part from the specific range of the other radiographic image;
It is characterized by having.

  In this case, when a specific part is selected from one radiographic image, a specific range including the specific part in the other radiographic image is obtained and displayed on the other radiographic image. The operator can easily select a corresponding specific part from the displayed specific range. And the position of a specific part is correctly calculated | required from the positional information on the same specific part selected from each radiographic image.

  In the radiographic image processing system and processing method of the present invention, a corresponding specific part can be easily and accurately selected from two sets of radiographic images obtained by photographing a subject from a plurality of different directions. As a result, the position of the specific part can be obtained accurately.

  FIG. 1 is a configuration diagram of a mammography apparatus 20 that is an embodiment to which a radiation image processing system and a processing method of the present invention are applied.

  The mammography apparatus 20 includes a base 22 installed in an upright state, an arm member 26 fixed to a turning shaft 24 disposed at a substantially central portion of the base 22, and a mammo 28 (subject, 2), a radiation source 30 (FIG. 3) for irradiating radiation X is housed, a radiation source housing portion 32 fixed to one end of the arm member 26, and a solid for detecting the radiation X transmitted through the mammo 28. An imaging table 36 in which the detector 34 (radiation detector, FIGS. 2 and 3) is housed and fixed to the other end of the arm member 26, and a compression plate that compresses and holds the mammo 28 against the imaging table 36. 38 and a biopsy hand unit 40 (biopsy device) that is attached to the compression plate 38 and collects a necessary tissue from a biopsy site (specific site) of the mammo 28. The base 22 displays imaging information such as the imaging region and imaging direction of the subject 27, ID information of the subject 27, and the like, and a display operation unit 42 that can set such information as necessary. Arranged.

  The arm member 26 that couples the radiation source storage unit 32 and the imaging stand 36 is configured so that the imaging direction of the subject 27 with respect to the mammo 28 can be adjusted by rotating about the rotation axis 24. The radiation source storage unit 32 is connected to the arm member 26 via a hinge unit 35 and is configured to be movable independently of the imaging table 36 in the direction of the arrow θ. In this case, two sets of radiation images can be acquired by performing imaging by moving the radiation source storage unit 32 to two different locations via the hinge unit 35. The compression plate 38 is disposed between the radiation source storage unit 32 and the imaging table 36 while being connected to the arm member 26, and is configured to be displaceable in the arrow Z direction.

  The compression plate 38 is formed with an opening 44 for tissue collection using the biopsy hand unit 40. The biopsy hand unit 40 includes a post 46 fixed to the compression plate 38, a first arm 48 having one end pivotally supported by the post 46, and capable of turning along the surface of the compression plate 38, and the first arm 48. One end is pivotally supported by the end, and a second arm 50 that can pivot along the surface of the compression plate 38 is provided. A biopsy needle 52 that can move in the arrow Z direction is attached to the other end of the second arm 50. As shown in FIG. 2, the biopsy needle 52 has a collection unit 56 that sucks and collects the tissue of the biopsy site 54 of the mammo 28. The collection unit 56 of the biopsy needle 52 moves the first arm 48 and the second arm 50 of the biopsy hand unit 40 in the XY plane along the surface of the compression plate 38 and moves the biopsy needle 52 in the arrow Z direction. By moving it, it can be placed near the biopsy site 54.

  FIG. 3 is a control circuit block diagram constituting the mammography apparatus 20.

  The mammography apparatus 20 includes processing conditions such as subject information relating to the age, sex, body type, subject identification number, etc. of the subject 27, radiographic imaging conditions, imaging method, and parameters defining the position of the radiation source 30 with respect to the imaging table 36. The radiation source 30 according to the processing condition setting unit 58 for setting the radiography and the set imaging conditions, for example, the tube current, the tube voltage, the type of target or filter set to the radiation source 30, the radiation X irradiation dose, the irradiation time, etc. A radiation source drive control unit 60 that controls the drive, a compression plate drive control unit 62 that moves the compression plate 38 in the arrow Z direction (FIG. 2), and a solid state detector 34 that detects the radiation X transmitted through the mammo 28. And a biopsy needle drive control unit 66 that moves the biopsy needle 52 to a predetermined position via the biopsy hand unit 40.

  Position information of the compression plate 38 that is moved by the compression plate drive control unit 62 with respect to the imaging stand 36 is calculated by a compression plate position information calculation unit 70. The detector control unit 64 controls the solid state detector 34 to acquire radiation image information, and stores the radiation image information in the image information storage unit 72. The radiation image information stored in the image information storage unit 72 is subjected to CAD (Computer Aided Diagnosis) processing, which is quantitative analysis processing, by the CAD processing unit 74 (detection processing unit), and abnormal candidate sites are detected from the radiation image information. Extracted. The radiation image and the abnormal candidate site are processed by the display processing unit 76 (warning processing unit) and displayed on the display unit 78. Note that the display unit 78 displays two sets of radiation images captured by moving the radiation source 30 to two different locations.

  The mammography apparatus 20 includes a biopsy site selection unit 80 (selection unit) in which an operator selects a desired biopsy site from two sets of radiographic images displayed on the display unit 78. Note that the biopsy site selection unit 80 includes, for example, a mouse, a touch panel, a cursor moving unit, and the like for selecting a desired biopsy site from a radiation image including a plurality of abnormal candidate sites displayed on the display unit 78. be able to. The biopsy site position information calculation unit 82 (position calculation unit) determines the biopsy site selected by the biopsy site selection unit 80 based on the parameters that define the position of the radiation source 30 supplied from the processing condition setting unit 58. The position information is calculated, and the position information is supplied to the biopsy site range calculation unit 84 (range calculation unit). Further, the biopsy site position information calculation unit 82 supplies the calculated biopsy site position information to the biopsy needle drive control unit 66, and the biopsy needle drive control unit 66 sets the biopsy hand unit 40 according to the supplied position information. Drive control is performed to control the movement of the biopsy needle 52 to the vicinity of the biopsy site.

  The biopsy site range calculation unit 84 calculates a range in which the biopsy site of the other radiographic image corresponding to the biopsy site selected from one of the two radiographic images displayed on the display unit 78 exists. Based on the biopsy site position information of one of the radiographic images calculated by the biopsy site position information calculation unit 82 and the parameter defining the position of the radiation source 30 supplied from the processing condition setting unit 58 . The biopsy site range information calculated by the biopsy site range calculation unit 84 is stored in the range information storage unit 86 (range storage unit). The display unit 78 displays the calculated biopsy site range so as to overlap the other radiation image.

  The mammography apparatus 20 of the present embodiment is basically configured as described above. Next, the operation will be described with reference to the flowchart shown in FIG.

  First, using the processing condition setting unit 58, subject information relating to the age, sex, body type, subject identification number, etc. of the subject 27, imaging conditions of radiographic image information, imaging method, and position of the radiation source 30 with respect to the imaging table 36 are determined. Processing conditions such as prescribed parameters are set (step S1). These processing conditions can be confirmed by displaying them on the display operation unit 42 of the mammography apparatus 20. Among the set processing conditions, imaging conditions such as tube current, tube voltage, radiation X irradiation dose, and irradiation time of the radiation source 30 are set in the radiation source drive control unit 60. In addition, parameters that define the position of the radiation source 30 with respect to the imaging table 36 are set in the biopsy site position information calculation unit 82 and the biopsy site range calculation unit 84.

  Next, the engineer positions the mammo 28 of the subject 27 in accordance with the designated imaging method (step S2). That is, after placing the mammo 28 at a predetermined position on the imaging table 36, the compression plate drive control unit 62 moves the compression plate 38 toward the imaging table 36 to compress the mammo 28 and perform positioning. The position information of the compression plate 38 is calculated by the compression plate position information calculation unit 70 and supplied to the biopsy site range calculation unit 84.

  After the positioning is completed, the radiation source 30 is driven and stereo imaging of the mammo 28 is performed (step S3). In this case, the radiation source storage unit 32 is moved in the direction of the arrow θ around the hinge unit 35 (FIG. 1), and the radiation source 30 is disposed at the A position and the B position as shown in FIG. The radiation image information of the mammo 28 at each position is acquired. That is, by arranging the radiation source 30 at the A position and the B position and irradiating the radiation X, the radiation X transmitted through the mammo 28 is detected as radiation image information by the solid state detector 34 of the imaging stand 36. The detector control unit 64 controls the solid state detector 34 to acquire the radiation image information of the mammo 28 at the A position and the B position, and temporarily stores these two sets of radiation image information in the image information storage unit 72. .

  Each radiographic image information stored in the image information storage unit 72 is subjected to CAD processing by the CAD processing unit 74, and an abnormal candidate site is extracted from each radiographic image information (step S4). Each radiographic image including the abnormal candidate site is processed by the display processing unit 76 and displayed on the display unit 78 as shown in FIG. 6 (step S5). For example, the display unit 78 displays two sets of radiographic images 88A and 88B taken at the A position and the B position, and abnormal candidate portions 90A and 92A extracted from the radiographic images 88A and 88B by CAD processing. An arrow-shaped marker 94 indicating 90B and 92B is displayed. The CAD processing unit 74 can automatically extract the abnormal candidate portions 90A, 92A, 90B, and 92B using an iris filter or a morphology filter (see Japanese Patent Laid-Open No. 8-294479).

  Next, the operator uses the biopsy site selection unit 80 such as a mouse to select an abnormal candidate site 90A or 92A that is determined to be biopsyed from one of the radiographic images 88A displayed on the display unit 78. It selects as a biopsy site | part (step S6). The biopsy site position information calculation unit 82 calculates the position information on the radiographic image 88A of the selected biopsy site and supplies it to the biopsy site range calculation unit 84 (step S7). The biopsy site range calculation unit 84 calculates a biopsy site range including the corresponding abnormal candidate site 90B or 92B on the other radiographic image 88B according to the supplied positional information of the abnormal candidate site 90A or 92A (step S8). ).

  A method for calculating the biopsy site range will be described with reference to FIG.

The biopsy site 54 of the mammo 28 selected from one radiographic image 88A is a straight line CD (point C is the intersection of the straight line AD and the compression plate 38, and point D is an extension of the straight line AC and the solid detector 34. Exists on the intersection). Therefore, the biopsy site 54 on the other radiographic image 88B is a straight line DE (point E is the intersection of the extension line of the straight line BC and the imaging table 36) obtained by projecting the biopsy site 54 onto the solid detector 34. Exists in range. The inclination angle of the radiation source 30 with respect to the symmetry axis 96 when the radiation source 30 is moved to the A position and the B position is α, the distance between the radiation source 30 and the solid detector 34 at which the symmetry axis 96 intersects is L, and the solid If the distance between the detector 34 and the compression plate 38 is h, the biopsy site range a, which is the length of the straight line DE, from the similar conditions of the triangle ABC and CDE is:
(Lcos α−h): h = 2L sin α: a
It can be calculated from the relationship.

  Therefore, the biopsy site range calculation unit 84 stores the calculated biopsy site range a in the range information storage unit 86 (step S9). On the other hand, the display processing unit 76, based on the biopsy site range a, as shown in FIG. 6, a range in which there is an abnormal candidate site 90B or 92B corresponding to the abnormal candidate site 90A or 92A selected from one radiographic image 88A. Is superimposed and displayed on the other radiation image 88B as the specific range 98 (step S10).

  In FIG. 6, when an abnormal candidate site 90A is selected by the operator from one radiographic image 88A, the biopsy site ranges a and b are formed so as to surround the corresponding abnormal candidate site 90B in the other radiographic image 88B. Although the rectangular specific range 98 is displayed, as shown in FIG. 7, a linear specific range 100 consisting only of the biopsy site range a may be displayed.

  By the way, for example, when the operator selects the abnormal candidate parts 90A and 92A from the radiographic image 88A, if the part without the abnormal candidate parts 90A and 92A is selected by mistake, the specific range 98 displayed on the radiographic image 88B is displayed. There may be no abnormal candidate site in the area. The display processing unit 76 determines whether or not there is an abnormal candidate site (step S11). If there is no abnormal candidate site, the display processing unit 76 displays a warning on the display unit 78 (step S12). The user is prompted to perform the process of selecting the abnormal candidate portions 90A and 92A again from the radiation image 88A. Further, in the CAD process in step S4, there may be a case where an abnormal candidate site cannot be extracted within the specific range 98 of the radiation image 88B. In this case as well, warning processing is performed. In addition to warning display on the display unit 78, warning processing may be performed by warning sound, vibration, or the like.

  Next, the operator uses the biopsy site selection unit 80 to select abnormal candidate sites 90B and 92B corresponding to the abnormal candidate sites 90A and 92A selected from the radiographic image 88A from within the specific range 98 displayed on the radiographic image 88B. Is selected (step S13). In this case, since the abnormal candidate sites 90B and 92B are selected from the displayed specific range 98, the corresponding abnormal candidate sites 90B and 92B can be easily and accurately selected.

  When selecting abnormal candidate sites 90A, 92A, 90B, 92B from the radiographic images 88A, 88B, a local region including the abnormal candidate sites 90A, 92A, 90B, 92B is extracted from the radiographic images 88A, 88B in the CAD process. If the operator's observation consciousness is concentrated on the local area by displaying the enlarged image, the abnormal candidate sites 90A, 92A, 90B, and 92B can be selected more reliably.

  For example, in the radiographic images 88A and 88B of the mammo 28 photographed for the purpose of breast cancer examination, a search for a calcium deposit called microcalcification is performed, but since the site is fine, the radiographic images 88A and 88B. It is difficult to select from the whole. Therefore, if a local region including a shape and brightness of each micro calcification and a calcification cluster in which a plurality of micro calcified portions are connected is extracted and the portion is enlarged and displayed, the abnormal candidate portions 90A and 92A are displayed. , 90B, and 92B are more easily selected (see Japanese Patent Laid-Open No. 2000-237176).

  When the corresponding biopsy site 54 is selected from each of the radiographic images 88A and 88B, the biopsy site position information calculation unit 82 uses the two-dimensional position information of the selected biopsy site 54 to set 3 in the mammo 28. The dimension position information is calculated (step S14).

  The calculated position information of the biopsy site 54 is supplied to the biopsy needle drive control unit 66, and the biopsy hand unit 40 is driven and controlled so that the biopsy needle 52 is inserted into the mammo 28 and the desired biopsy site is obtained. It moves to the vicinity of 54 (step S15).

  When the collection part 56 of the biopsy needle 52 reaches the vicinity of the biopsy site 54, suction processing by the biopsy needle 52 is started, and the biopsy site 54 is collected (step S16). Thereafter, the biopsy needle 52 is extracted from the mammo 28, and the operation is completed (step S17).

  In addition, this invention is not limited to embodiment mentioned above, Of course, it can change freely in the range which does not deviate from the main point of this invention.

  For example, when the radiation source 30 is arranged at two different A positions and B positions, and two sets of radiation images 88A and 88B are acquired and displayed on the display unit 78, the corresponding abnormality candidate is caused by the overlap of mammary glands and the like. There is a possibility that the portions 90A, 90B, 92A, and 92B cannot be selected. Therefore, the radiation sources 30 are arranged at three or more different positions, three or more sets of radiation images are acquired and displayed on the display unit 78, and from these plurality of radiation images, abnormal candidate sites 90A, 90B, 92A, The radiation image specific range 98 may be calculated by selecting two sets of radiation images that can designate 92B.

  Further, a radiographic image taken after the biopsy site 54 is collected using the biopsy hand unit 40 is displayed on the display unit 78, and the specific range 98 calculated before the biopsy site 54 is sampled for the radiographic image. Is read from the range information storage unit 86 and displayed, it can be confirmed whether or not the biopsy site 54 has been collected from the specific range 98.

  Of course, the present invention can also be applied to a radiographic image processing apparatus other than a mammography apparatus or a biopsy apparatus.

It is a block diagram of the mammography apparatus of this embodiment. It is principal part side explanatory drawing of the mammography apparatus containing a biopsy hand part. It is a control circuit block diagram which comprises the mammography apparatus of this embodiment. It is an operation | movement flowchart of the mammography apparatus of this embodiment. In the mammography apparatus of this embodiment, it is explanatory drawing for calculating the specific range of a biopsy site | part. It is explanatory drawing of two sets of radiographic images displayed on the display part of the mammography apparatus of this embodiment, and a specific range. It is explanatory drawing of the other form of the specific range shown in FIG. It is explanatory drawing of two sets of radiographic images with which it uses for description of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 ... Mammography apparatus 28 ... Mammo 30 ... Radiation source 32 ... Radiation source storage part 34 ... Solid state detector 36 ... Imaging stand 38 ... Compression plate 40 ... Biopsy hand part 54 ... Biopsy site 58 ... Processing condition setting part 70 ... Compression plate Position information calculation unit 74 ... CAD processing unit 78 ... display unit 80 ... biopsy site selection unit 82 ... biopsy site position information calculation unit 84 ... biopsy site range calculation unit 86 ... range information storage units 88A, 88B ... radiation image 90A , 92A, 90B, 92B ... abnormal candidate part 94 ... marker 98, 100 ... specific range

Claims (16)

An imaging unit for imaging a subject from a plurality of different directions and acquiring a plurality of sets of radiation images;
A display unit for displaying a plurality of sets of the radiation images;
A selection unit that selects a specific part from each of two predetermined sets of radiographic images among the plurality of sets of radiographic images displayed on the display unit;
A range calculation unit for calculating a specific range of the other radiographic image including the specific part selected from the one radiographic image;
And the display section displays the calculated specific range on the other radiographic image. The system of claim 1, wherein
A radiation image processing system, comprising: a position calculation unit that calculates a position of the specific part from the two sets of the specific parts selected by the selection unit. The system of claim 1, wherein
A radiation image processing system comprising: a detection processing unit that performs a detection process of detecting an abnormal candidate site that can be the specific site from the radiographic image, and the display unit displays the detected abnormal candidate site. The system of claim 3, wherein
A radiation image processing system comprising: a warning processing unit that performs a warning process when the detection processing unit cannot detect the abnormal candidate site in the specific range. The system of claim 1, wherein
A radiation image processing system comprising: a range storage unit that stores the calculated specific range, wherein the display unit displays the specific range stored in the range storage unit. The system of claim 1, wherein
A radiographic image processing system comprising a biopsy device for collecting a tissue for biopsy from the specific site. The system of claim 6, wherein
A position calculation unit that calculates the position of the specific part from the two sets of specific parts selected by the selection unit; and the biopsy device collects the tissue from the calculated position. Radiation image processing system. The system of claim 1, wherein
The radiographic image processing system, wherein the imaging unit constitutes a mammography apparatus. The system of claim 1, wherein
The imaging unit includes a radiation source that irradiates the subject with radiation, and a radiation detector that detects the radiation transmitted through the subject,
The range calculation unit includes a distance between the radiation source and the radiation detector, a distance between the two positions when the radiation source is moved to two different positions and the subject is imaged, and a thickness of the subject. The specific range is calculated using a radiation image processing system. The system of claim 9, wherein
The range calculation unit determines the specific range a as a tilt angle α of the radiation source with respect to the radiation detector, a distance Lcosα between the radiation source and the radiation detector, a distance 2Lsinα between the two positions, and a thickness of the subject. Using h
(Lcos α−h): h = 2L sin α: a
The radiation image processing system characterized by calculating from the relationship. Photographing a subject from a plurality of different directions and acquiring a plurality of sets of radiation images;
Displaying a plurality of sets of the radiation images;
Selecting a specific part from one of the predetermined two sets of the radiographic images among the plurality of displayed radiographic images;
Obtaining a specific range including the selected specific part from the other radiographic image;
Displaying the specific range on the other radiographic image;
Selecting the specific part from the specific range of the other radiographic image;
A radiation image processing method comprising: The method of claim 11 wherein:
A radiographic image processing method comprising a step of calculating a position of the specific part from the two selected sets of specific parts. The method of claim 11 wherein:
Detecting an abnormal candidate site that can be the specific site from the radiation image;
Displaying the detected abnormal candidate site;
Selecting the specific site from the abnormal candidate sites;
A radiation image processing method comprising: 14. The method of claim 13, wherein
A radiographic image processing method comprising a step of performing a warning process when the abnormal candidate part is not included in the specific range. The method of claim 11 wherein:
The specific range is a distance between a radiation source that irradiates the subject with radiation and a radiation detector that detects the radiation transmitted through the subject, and the radiation source is moved to two different positions. A radiographic image processing method comprising: calculating using a distance between the two positions at the time of photographing and a thickness of the subject. The method of claim 15, wherein
The specific range a is determined by using an inclination angle α of the radiation source with respect to the radiation detector, a distance Lcosα between the radiation source and the radiation detector, a distance 2Lsinα between the two positions, and a thickness h of the subject.
(Lcos α−h): h = 2L sin α: a
The radiation image processing method characterized by calculating from the relationship of these.

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