JP2010088586A - Mammography system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mammography system which can easily position the breast of a subject being tested. <P>SOLUTION: The mammography system includes a radiographic stand 11 for supporting a part P1 to be radiographed which is the breast of the subject P, first and second compressing plates 12 and 13 for compressing the part P1 to be radiographed which is supported by the radiographic stand 11, an X-ray generator 20 for irradiating the part P1 to be radiographed which is compressed by the first and second compressing plates 12 and 13 with X rays, an X-ray detector 30 for detecting X rays which are emitted by the X-ray generator 20 and transmit through the part P1 to be radiographed and generating X-ray projection data and an image processor 3 for processing the X-ray projection data which is generated by the X-ray detector 30 and generating image data. The first compressing plate 12 compresses and fixes parts adjacent to a chest wall of the part P1 to be radiographed which is supported by the radiographic stand 11. After the parts adjacent to the chest wall of the part P1 to be radiographed are compressed and fixed, the second compressing plate 13 compresses parts other than the parts adjacent to the chest wall of the part P1 to be radiographed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a mammography apparatus that performs X-ray imaging of a breast of a subject.

  2. Description of the Related Art A mammography apparatus that obtains image data by X-ray imaging of a breast with the subject's breast as the object of examination is known (see, for example, Patent Document 1). This mammography device is equipped with an imaging table that supports the breast and a compression plate that compresses the breast supported by the imaging table, and by compressing the breast flat with this compression plate, motion blur and overlap of mammary glands are reduced. By reducing the thickness of the breast, image data with high contrast can be obtained with less X-ray scattering.

When compressing the breast with this compression plate, the operator who performs X-ray imaging first determines the position of the breast supported by the imaging table, and then lowers the compression plate from the position held by the hand so that the breast does not move. The compression is fixed. For this reason, it is necessary to extract the hand when the pressure of the compression plate is applied to the hand holding the breast.
JP 2004-33790 A

  However, it is difficult to extract the hand while the pressure is applied to the hand holding the breast, and there is a problem that the breast is displaced from a predetermined position if the hand is forcibly extracted.

  There is also a compression plate with a structure that makes it easy to extract a hand suitable for compression of a small breast. However, since the size is smaller than a normal compression plate, there is a problem that it is impossible to compress a breast having a size larger than that of a small breast. In addition, when compressing a breast having a size larger than that of a small breast, it is necessary to replace the compression plate with a normal compression plate.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a mammography apparatus that can easily position a breast of a subject.

  In order to solve the above problem, a mammography apparatus of the present invention includes an imaging table that supports a breast of a subject, first and second compression plates that compress the breast supported by the imaging table, and the first X-ray generation means for irradiating X-rays to the breast whose part other than the part is compressed by the second compression plate after being partially compressed by the first compression plate, and by the X-ray generation means X-ray detection means for generating X-ray projection data by detecting X-rays irradiated and transmitted through the breast, and an image for generating image data by processing the X-ray projection data generated by the X-ray detection means And a processing means.

  According to the present invention, when two compression plates are provided and a breast having a size larger than a small breast is to be compressed, a part of the breast positioned on the imaging table is compressed and fixed with one compression plate, and then one is compressed. The breast can be easily positioned by compressing the portion other than the portion with the other compression plate. In addition, when a breast having a size larger than that of a small breast is compressed, it is possible to easily position the breast by using one of the compression plates, so that it is possible to reduce the trouble of replacing the compression plate.

  Examples of the present invention will be described.

  Hereinafter, an embodiment of a mammography apparatus according to the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram showing a configuration of a mammography apparatus according to an embodiment of the present invention. The mammography apparatus 100 includes an imaging unit body 1 that generates X-ray projection data by X-ray imaging of an imaging site P1 that is a breast of a subject P, and a high voltage necessary for X-ray imaging of the imaging unit body 1. A high voltage generation unit 2 to be supplied and an image processing unit 3 that processes X-ray projection data generated by the imaging unit main body 1 to generate image data are provided.

  The mammography apparatus 100 also includes a display unit 4 for displaying the image data generated by the image processing unit 3, setting of imaging conditions such as X-ray irradiation conditions, setting of various conditions related to display, input of various commands, etc. An operation unit 5 that performs operations and a system control unit 6 that controls these units in an integrated manner are provided.

  As shown in FIG. 2, the imaging unit body 1 includes an imaging unit 7 that generates X-ray projection data by X-ray imaging of the imaging region P1, and moves the imaging unit 7 in the vertical direction and in the direction of the arrow R1. And a main body support portion 8 that supports the rotation.

  FIG. 3 is a perspective view showing the appearance of the photographing unit 7. The imaging unit 7 includes a compression unit 10 that compresses the imaging region P1, an X-ray generation unit 20 that irradiates the imaging region P1 compressed by the compression unit 10, and an X-ray from the X-ray generation unit 20. An X-ray detection unit 30 that detects X-rays transmitted through the imaging region P1 by irradiation and generates X-ray projection data, and a cover that covers a part of the X-ray generation unit 20, the X-ray detection unit 30, and the compression unit 10 40.

  FIG. 4 is a diagram illustrating the configuration of the compression unit 10. The compression unit 10 is disposed between the X-ray generation unit 20 and the X-ray detection unit 30, and includes an imaging table 11 that supports the imaging region P1, and a first and a second that compress the imaging region P1 supported by the imaging table 11. Second compression plates 12 and 13 and first and second moving parts 14 and 15 that move the first and second compression plates 12 and 13 are provided.

  The imaging table 11 is made of, for example, a plate-like carbon composite material having excellent X-ray transparency, and a support surface 11a that supports the imaging region P1 is a flat surface.

  The first compression plate 12 is made of, for example, an acrylic material that is smaller than the size of a conventional normal compression plate and excellent in X-ray transmission, and is disposed to face the imaging table 11. Further, the compression surface 12a that compresses the imaging region P1 forms a flat surface and is arranged in parallel to the support surface 11a of the imaging table 11, and the arrow L1 that is the direction approaching the imaging table 11 and this L1 direction It is supported by the first moving part 14 so as to be movable in the direction of the arrow L2, which is the opposite direction.

  When the imaging region P1 is a small breast, the first compression plate 12 is moved in the L1 direction, and then stretched on the imaging table 11 and compressed flatly over the entire imaging region P1 whose position is determined. Stop in the state.

  Thus, when the imaging region P1 is a small breast, the imaging region P1 can be easily positioned by using the first compression plate 12.

  In addition, when the imaging region P1 is a breast having a size larger than the small breast, the portion other than the vicinity of the chest wall of the imaging region P1 is extended so that the imaging region P1 that extends on the imaging table 11 and does not move is moved. After the first compression plate 12 is moved in the L1 direction while being pressed, the operation is stopped in a state where the vicinity of the chest wall of the imaging region P1 is flatly compressed and fixed.

  As described above, when the imaging region P1 is a breast having a size larger than that of the small breast, the imaging region P1 can be positioned without being caught between the imaging table 11 and the first compression plate 12. Thereby, the imaging region P1 can be easily positioned without causing a positional shift of the imaging region P1.

  The second compression plate 13 is made of, for example, an acrylic material having excellent X-ray permeability that is the size of a conventional normal compression plate together with the first compression plate 12, for example, and is disposed to face the imaging table 11. The In addition, a compression surface 13 a that is disposed between the first compression plate 12 and the first and second moving units 14 and 15 and that compresses the imaging region P <b> 1 forms a flat surface with respect to the support surface 11 a of the imaging table 11. Arranged in parallel. Further, like the first compression plate 12, it is supported by the second moving portion 15 so as to be movable in the L1 direction and the L2 direction.

  When the imaging region P1 is larger than the small breast, after the second compression plate 13 is moved in the L1 direction after the first compression plate 12 fixes the vicinity of the chest wall of the imaging region P1, the imaging region Stop in a state where the stretched part other than the vicinity of the chest wall of P1 is pressed flat.

  As described above, when the imaging region P1 is a breast having a size larger than the small breast, since the vicinity of the chest wall of the imaging region P1 is compressed and fixed by the first compression plate 12, the imaging region P1 does not cause a positional shift. It is possible to compress the part other than the vicinity of the chest wall.

  The first moving unit 14 includes a first moving mechanism 141 that moves the first compression plate 12 in the L1 direction and the L2 direction, and first L1 and L2 directions provided in the first moving mechanism 141. A first position detector 142 such as a potentiometer for detecting the position of the compression plate 12 and a first pressure detector 143 for detecting the pressure of the first compression plate 12 that has compressed the imaging region P1.

  The first moving mechanism 141 has two first arms 141a that support the first compression plate 12 at both end faces in the longitudinal direction, and the first arm 141a is driven to move. The compression plate 12 is moved in the L1 direction and the L2 direction. Further, the first position detector 142 detects the position of the first compression plate 12 moved by the first moving mechanism 141 and outputs the position detection signal to the system control unit 6. Further, the first pressure detector 143 detects the pressure that the first moving mechanism 141 has moved and the first compression plate 12 has pressed the imaging region P1, and outputs the pressure detection signal to the system control unit 6. To do.

  The second moving unit 15 includes a second moving mechanism 151 that moves the second compression plate 13 in the L1 direction and the L2 direction, and a second moving mechanism 151 provided in the second moving mechanism 151 in the L1 direction and the L2 direction. A second position detector 152 such as a potentiometer for detecting the position of the compression plate 13 and a second pressure detector 153 for detecting the pressure of the second compression plate 13 that has pressed the imaging region P1.

  The second moving mechanism 151 includes a second arm 151a that supports the second compression plate 13 on both end surfaces in the longitudinal direction and the end surface on the opposite side to the first compression plate 12 side in the width direction. Then, the second arm 151a is driven to move, and the second compression plate 13 is moved in the L1 direction and the L2 direction. The second position detector 152 detects the position of the second compression plate 13 moved by the second moving mechanism 151 and outputs the position detection signal to the system control unit 6. Further, the second pressure detector 153 detects the pressure at which the second moving mechanism 151 moves and the second compression plate 13 presses the imaging region P1, and outputs the pressure detection signal to the system control unit 6. To do.

  The first and second moving units 14 and 15 are arranged at positions outside the X-ray irradiation range of the X-ray generation unit 20.

  The X-ray generator 20 shown in FIG. 1 is located between an X-ray tube 21 that generates X-rays, and the first and second compression plates 12 and 13 of the X-ray tube 21 and the compression unit 10. An X-ray diaphragm 22 that controls the X-ray irradiation range emitted from the X-ray tube 21 and applied to the imaging region P1 within a range that can be detected by the X-ray detection unit 30 is provided. Then, X-rays are irradiated to the imaging region P1 compressed by the compression unit 10. Note that low energy X-rays are irradiated because it is necessary to extract a normal tissue in the imaging region P1 and a lesion tissue having a small X-ray absorption difference with high contrast.

  The X-ray detector 30 is disposed opposite to the X-ray generator 20, detects an X-ray and converts it into an electrical signal, and a signal converted by the X-ray detector 31. And a signal processing unit 32 for generating X-ray projection data. Then, X-ray projection data generated by detecting X-rays transmitted through the imaging region P1 compressed by the compression unit 10 is output to the image processing unit 3.

  In this way, by pressing the imaging region P1 flatly with the compression unit 10, it is possible to reduce blurring due to movement and overlap of mammary glands, and to reduce X-ray scattering by reducing the thickness of the imaging region P1. Therefore, it is possible to obtain image data in which a mammary gland having a high contrast is clearly projected.

  The cover 40 shown in FIG. 3 has an opening other than the opening for irradiating the imaging region P1 of the X-ray generation unit 20 with X-rays, a detection surface other than the detection surface for detecting X-rays of the X-ray detection unit 30, and the first and second The first and second arms 141a and 151a and the first and second arms 141a and 151a that support the first and second compression plates 12 and 13 of the moving parts 14 and 15 are provided to be movable. Covers all but the opening.

  The high voltage generator 2 shown in FIG. 1 is based on the tube voltage, tube current, X-ray irradiation time, etc., which are X-ray irradiation conditions included in the imaging conditions supplied from the system control unit 6. A high voltage for generating X-rays is supplied to the X-ray tube 21 of the X-ray generator 20 in the imaging unit 7.

  The image processing unit 3 generates image data from the X-ray projection data output from the signal processing unit 32 of the X-ray detection unit 30 in the imaging unit 7 of the imaging unit body 1, and outputs the generated image data to the display unit 4. To do. The generated image data is stored.

  The display unit 4 includes a monitor such as a liquid crystal panel or a CRT, and displays the image data output from the image processing unit 3.

  The operation unit 5 includes input devices such as a keyboard, a mouse, and various switches, and includes an input operation for setting shooting conditions, an input operation for moving the imaging unit 7 up and down, and first and second compression plates 12 and 13. Are operated in the L1 and L2 directions, an input operation for starting the inspection, an input operation for ending the inspection, and the like.

  The system control unit 6 includes a CPU and a storage circuit, temporarily stores input information such as a command signal and imaging conditions supplied from the operation unit 5, and then controls the entire system based on the input information. Further, the second moving mechanism 151 of the second moving unit 15 is controlled based on the position detection signal output from the first position detector 142 of the first moving unit 14.

Hereinafter, an example of the operation of the mammography apparatus 100 will be described with reference to FIGS. 1 to 7.
FIG. 5 is a flowchart showing the operation of the mammography apparatus 100. When an operation for inputting subject information for identifying the subject P to be examined and examination information such as an imaging condition including an X-ray irradiation condition is performed from the operation unit 5, the mammography apparatus 100 starts an operation of performing an examination ( Step S1).

  Based on the examination information input from the operation unit 5, the system control unit 6 instructs the imaging unit body 1, the image processing unit 3, and the display unit 4 to examine the subject P. By the input operation from the operation unit 5, the first and second compression plates 12, 13 are moved in the L2 direction. Next, after the imaging part P1, which is a breast having a size larger than the small breast, for example, of the subject P to be examined is extended on the support surface 11a of the imaging table 11 and positioned, the imaging part P1 does not move. When an operation of moving the first compression plate 12 in the L1 direction from the operation unit 5 in a state where the operator presses a portion other than the vicinity of the chest wall of the imaging region P1 with the hand, the first moving unit 14 After moving the first compression plate 12 in the L1 direction, the moving mechanism 141 compresses the vicinity of the chest wall of the imaging region P1 with the first compression plate 12 (step S2).

  The first pressure detector 143 outputs a pressure detection signal of the first compression plate 12 that has compressed the imaging region P <b> 1 to the system control unit 6. The system control unit 6 generates pressure data that is a force for pressing the imaging region P1 with the first compression plate 12 from the pressure detection signal from the first pressure detector 143, and displays the pressure data on the display unit 4 (step S3). .

  When the pressure data displayed on the display unit 4 reaches a predetermined pressure value, when the operation unit 5 is operated to stop the first compression plate 12, the first compression plate 12 is shown in FIG. As described above, the first moving mechanism 141 stops in a state where the vicinity of the chest wall of the imaging region P1 supported by the imaging table 11 is compressed and fixed (step S4).

  As described above, when the imaging region P1 is larger in size than the small breast, the first compression plate 12 is used to hold the portion other than the vicinity of the chest wall of the imaging region P1 with the hand and the vicinity of the chest wall of the imaging region P1. The imaging region P1 can be positioned by pressing and fixing. As a result, the imaging region P1 can be positioned without a hand being caught between the imaging table 11 and the first compression plate 12, and the imaging region P1 can be easily positioned without causing a positional shift of the imaging region P1. Can be done.

  The first position detector 142 detects the position where the first compression plate 12 stops and outputs the position detection signal to the system control unit 6. The system control unit 6 calculates, for example, the distance D1 between the imaging table 11 and the first compression plate 12 as the position information of the first compression plate 12 from the position detection signal output from the first position detector 142. And stored in an internal storage circuit.

  When an input operation for moving the second compression plate 13 in the L1 direction is performed from the operation unit 5 after positioning the imaging region P1 with the first compression plate 12, the second position detector 152 The position of the second compression plate 13 is detected and a position detection signal is output to the system control unit 6. The system control unit 6 controls the second compression mechanism 151 based on the position detection signal output from the second position detector 152 and the stopped position information of the first compression plate 12 to control the second compression. The plate 13 is activated. Then, as shown in FIG. 7, the second compression plate 13 has a distance between the end surface in the width direction and the imaging table 11 close to the end surface in the width direction of the first compression plate 12. At a position that is the same as the distance D1 between the compression plates 12, the portion other than the vicinity of the chest wall of the imaging region P1 is pressed and stopped (step S5).

  Thus, when the imaging region P1 is larger than the small breast, the position of the first compression plate 12 that is compression-fixed after the first compression plate 12 is used to compress and fix the vicinity of the chest wall of the imaging region P1. Based on the information, the second pressure plate 13 is stopped at a position separated from the imaging table 11 by the same distance as the first compression plate 12 to compress the portion other than the vicinity of the chest wall using the second compression plate 13. can do. Accordingly, it is possible to compress the entire region of the imaging region P1 with a uniform thickness.

  Next, when an X-ray imaging operation is performed from the operation unit 5, the high voltage generation unit 2 supplies a high voltage to the X-ray generation unit 20. The X-ray generation unit 20 irradiates the imaging region P1 compressed by the first and second compression plates 12 and 13 with X-rays. The X-ray detection unit 30 generates X-ray projection data by detecting X-rays that have passed through the imaging region P1, and outputs the generated X-ray projection data to the image processing unit 3. The image processing unit 3 generates image data based on the X-ray projection data output from the X-ray detection unit 30, displays the image data on the display unit 4, and stores the generated image data.

  In this manner, the imaging region P1 is compressed flatly by the imaging table 11 and the first and second compression plates 12 and 13, thereby reducing blur due to body movement and overlapping of the mammary glands and reducing the thickness of the imaging region P1. As a result, X-ray scattering can be reduced, and image data in which a mammary gland having a high contrast is clearly displayed can be obtained.

  After the desired image data is stored, when an input operation is performed to move the first and second compression plates 12 and 13 in the L1 direction from the operation unit 5, the first and second compression plates 12 and 13 are The first and second moving mechanisms 141 and 151 are moved in the L1 direction and stopped at a predetermined height. Next, when an input operation for ending the examination of the subject P is performed from the operation unit 5, the system control unit 6 instructs the imaging unit main body 1, the image processing unit 3, and the display unit 4 to end the examination. The mammography apparatus 100 ends the inspection operation (step S6).

  According to the embodiment of the present invention described above, the first and second compression plates 12 and 13 that compress the imaging region P1 supported by the imaging table 11 are provided, and the imaging region P1 has a size larger than that of the small breast. In the case of a breast, the first imaging plate 11 and the first imaging plate 11 are fixed by flatly pressing and fixing the vicinity of the chest wall of the imaging region P1 using the first compression plate 12 with the portion other than the vicinity of the chest wall of the imaging region P1 held by hand. The imaging region P <b> 1 can be positioned without a hand being caught between the one compression plate 12. Thereby, the imaging region P1 can be easily positioned without causing a positional shift of the imaging region P1.

  After compressing and fixing the vicinity of the chest wall of the imaging region P1, the second pressure plate 13 is separated from the imaging table 11 by the same distance as the first compression plate 12 based on the positional information of the first compression plate 12 at that position. By stopping at the position, the portion other than the vicinity of the chest wall of the imaging region P1 can be pressed flat. Accordingly, it is possible to compress the entire region of the imaging region P1 with a uniform thickness.

  As described above, it is possible to reduce blurring due to body movements and overlap of mammary glands, and to reduce the scattering of X-rays by reducing the thickness of the imaging region P1, so that image data that clearly shows a mammary gland with high contrast can be obtained. Obtainable.

  When the imaging region P1 is a small breast, the imaging region P1 can be easily positioned by pressing the imaging region P1 using the first compression plate 12. Then, by properly using the first compression plate 12 and the first and second compression plates 12 and 13 in accordance with the size of the breast of the subject P, it is possible to reduce time and effort for exchanging the compression plate.

The block diagram which shows the structure of the mammography apparatus which concerns on the Example of this invention. The figure which shows the external appearance of the imaging | photography part main body which concerns on the Example of this invention. The perspective view which shows the external appearance of the imaging | photography part which concerns on the Example of this invention. The figure which shows the structure of the compression part which concerns on the Example of this invention. The flowchart which shows operation | movement of the mammography apparatus which concerns on the Example of this invention. The figure which shows the 1st compression board stopped in the state which compressed and fixed the chest wall vicinity of the imaging | photography site | part concerning the Example of this invention. The figure which shows the 2nd compression board stopped in the state which compressed the part other than the chest wall vicinity of the imaging | photography site | part concerning the Example of this invention.

Explanation of symbols

P1 imaging part 1 imaging part main body 2 high voltage generation part 3 image processing part 4 display part 5 operation part 6 system control part 7 imaging part 8 main body support part 10 compression part 11 imaging base 12 first compression plate 13 second compression Plate 14 First moving unit 15 Second moving unit 20 X-ray generation unit 21 X-ray tube 22 X-ray restrictor 30 X-ray detection unit 31 X-ray detector 32 Signal processing unit

Claims (5)

An imaging table that supports the breast of the subject,
First and second compression plates that compress the breast supported by the imaging table;
X-ray generation means for irradiating X-rays to the breast whose part other than the part is compressed by the second compression plate after being partially compressed by the first compression plate;
X-ray detection means for generating X-ray projection data by detecting X-rays irradiated by the X-ray generation means and transmitted through the breast;
A mammography apparatus comprising: an image processing unit that processes the X-ray projection data generated by the X-ray detection unit to generate image data. First and second moving means for moving the first and second compression plates to compress the breast;
The mammography apparatus according to claim 1, wherein the second compression plate is disposed between the first compression plate and the first and second moving means. The first moving means compresses the vicinity of the chest wall of the breast supported by the imaging table by moving the first compression plate,
The said 2nd moving means moved the said 2nd compression board, and compressed the part other than the chest wall vicinity of the said breast supported by the said imaging stand, The said 2nd movement means is characterized by the above-mentioned. Mammography device. Having first position detecting means for detecting the position of the first compression plate moved by the first moving means;
The second moving means moves the second pressure plate based on a position detection signal of the first compression plate detected by the first position detecting means. The mammography apparatus according to claim 2.   5. The mammography apparatus according to claim 4, wherein the second moving unit stops the second pressure plate at a position separated from the imaging table by the same distance as the first compression plate. 6. .

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