JP2010069241A - Tomographic breast imaging system - Google Patents

Abstract

A breast tomographic imaging apparatus capable of accurately imaging a breast region necessary for breast cancer image diagnosis in mammo CT.
SOLUTION: A top plate 20 having an opening 23 through which a breast 11 is passed, and a pusher 31 disposed above the opening 23 and pressing a back of a subject 10 lying on the top plate, and a pusher to the subject. A mammography couch provided with a pusher moving device that moves relative to the X-ray generator, an X-ray generator 41 that emits X-rays, an X-ray detector 42 that detects the incident intensity of X-rays, and an X-ray The generator 41 and the X-ray detector 42 are mounted at positions facing each other across the rotation axis, and the X-ray imaging apparatus rotating around the rotation axis and the X-ray imaging apparatus are moved up and down relative to the top plate. A photographing apparatus lifting device.
[Selection] Figure 1

Description

  The present invention relates to a breast tomographic imaging apparatus using computer tomography (CT), and more particularly to a breast tomographic imaging apparatus capable of appropriately imaging a breast.

  Traditionally, breast cancer testing has been performed using palpation and ultrasound. However, these tests could not be found easily without cancer cells that grew to some extent. In breast cancer diagnosis, it is important to detect minute calcifications. It has been reported that mammography is useful for the detection of early breast cancer because it is excellent in depicting minute calcifications. On the other hand, mammography has a problem that the breast is sandwiched by a compression plate in order to reduce unnecessary exposure and obtain a good image quality, and the thickness of the breast is made uniform, causing pain to the subject. In addition, since the obtained image is a simple X-ray transmission image, image diagnosis is difficult when a tumor or calcification overlaps with an object that forms an X-ray image such as a mammary gland.

  Thus, a breast tomographic imaging apparatus (mammo CT) has been proposed that can obtain an arbitrary tomographic image without giving pain to the subject due to breast compression. Since it is a tomographic image, it has been suggested that lesions that have been difficult to diagnose due to the overlap of X-ray opaque portions can be easily detected by conventional mammography, which may contribute to early detection of breast cancer.

Patent Document 1 and Patent Document 2 each disclose an example of mammo CT.
The mammo CT disclosed in Patent Document 1 includes a mammography bed having an opening at a breast position, a frame that rotates horizontally around the opening, a motor that moves the mammography bed and the frame, and a measurement device. And a control device for controlling a switch for operating the switch. The measurement apparatus includes an X-ray generation apparatus, an X-ray detection apparatus disposed opposite to the X-ray generation apparatus, and an arithmetic unit that reconstructs a tomographic image from an X-ray transmission image obtained by the X-ray detection apparatus.

The X-ray generation device and the X-ray detection device are mounted on a gantry and acquire an X-ray transmission image of the subject from each direction while rotating together around a rotation axis passing through the opening.
The X-ray generator emits X-rays at predetermined angles, for example, according to the drive switch. The X-ray is irradiated to the subject, and the X-ray transmitted through the subject enters the X-ray detection apparatus. The X-ray detection apparatus uses a flat panel detector (FPD) in which X-ray detection elements are arranged in a matrix on a plane. Each X-ray detection element accumulates the X-ray projected from the X-ray generator as a measurement signal corresponding to the remaining X-ray intensity absorbed by the substance in the optical path, and the FPD forms an X-ray transmission image of the subject. To do. The X-ray detection apparatus can transmit an X-ray transmission image by scanning the measurement signal of each detection element and sequentially outputting it. The X-ray transmission images accumulated in this way are reconstructed to create and display an X-ray tomographic image of the subject.

  When the subject lies face down on the mammography bed and places the breast to be measured on the opening, the breast hangs between the X-ray generator and the X-ray detector. The subject presses the chest against the opening so that the breast is exposed to the measurement area as close to the chest wall. In order to avoid overlooking signs of breast cancer, the breast should be fully pulled out of the chest wall at the position where the breast hangs down and received by the breast container, and the nipple is pushed up with a piston to fit the entire breast into the measurement area. To do. The breast container is formed in a cylindrical shape with a material that easily transmits X-rays. A cushion for relieving the pain of the subject can be provided on the inside.

  The X-ray generator and the FPD rotate around the breast as the subject, operate the X-ray generator for each predetermined angle, take an X-ray transmission image with the X-ray detector, and display the image on the reconstruction calculation device. Transmit the signal. The reconstruction calculation device reconstructs an X-ray transmission image into 3D, and creates an X-ray tomographic image of the breast. For example, 300 X-ray transmission images are taken and used per rotation.

  Note that the mammography X-ray CT apparatus disclosed in Patent Document 2 is very similar to that disclosed in Patent Document 1, and does not use a breast container, and includes an X-ray source and an X-ray detection unit. The only difference is that the hollow part formed between the enclosing frame and the top plate whose opening is closed with the breast is decompressed to bring it to the root of the naturally suspended breast. The device is equivalent to

In the X-ray tomographic image obtained by the conventional apparatus, the calcified portion absorbs X-rays as well as the bone portion, so it is possible to visualize relatively small calcification of about several millimeters in size. Improvement in detection rate is expected. In addition, it is expected to improve the detection ability of a lesioned part behind a tissue such as a mammary gland, which is difficult to detect by conventional mammography.
US Pat. No. 6,480,565 JP 2008-093135 A

  However, for diagnosis of the entire breast, it is necessary to position the subject so that a sufficient range of breasts is within the imaging range. In addition, since breast cancer also occurs near the chest wall, it is required to closely examine the area near the base of the breast as much as possible. However, in the method in which the subject presses the chest against the opening by himself, it is difficult for any subject to sufficiently expose the breast to the imaging range to the vicinity of the chest wall. In addition, a method of fixing a subject with a belt has been proposed in order to reduce blurring of a captured image due to body movement, but the range of the breast that can be included in the imaging range by the belt fixing method is determined by the operator. This method has a problem that the photographing range is not essentially secured. On the other hand, it is not possible to accept unnecessary X-ray exposure even for inspection.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a breast tomographic imaging apparatus capable of accurately imaging a breast area necessary for cancer screening in mammo CT. It is another object of the present invention to provide a breast tomographic imaging apparatus capable of managing an area other than the breast so as not to receive unnecessary X-ray exposure.

  In order to solve the above problems, a breast tomography apparatus according to the present invention comprises an opening through which a breast passes and a subject who lies down and hangs down the breast from the opening, and a horizontal movement of the top plate. A top plate moving device to be performed, a presser that is disposed above the opening through which the breast passes and presses the back of the subject lying on the top plate and a press adjuster that adjusts the pad press, and the pad A mammography bed provided with a pusher moving device that moves relative to the person, and an X-ray generator and an X-ray detector that are opposed to each other across a rotation axis perpendicular to the top plate portion A radiographic apparatus, an imaging apparatus rotating apparatus that rotates the X-ray imaging apparatus, and an imaging apparatus elevating apparatus that elevates and lowers the X-ray imaging apparatus relative to the top plate portion.

  According to the breast tomography apparatus according to the present invention, since the back of the subject who is hanging the breast from the opening of the top plate is pushed with the pad of the press, the subject pushes out the chest by himself and the breast Compared to the case where the X-ray generator is exposed between the X-ray generator and the X-ray detector, the breast can be surely pushed out to the vicinity of the root, and the inspection can be performed over a wider range. In particular, since an X-ray image includes a region in the vicinity of the ribs where cancer is often seen, examination with few oversights can be performed.

Also, a confirmation image is generated using a low-safety X-ray that is lower than usual, and the relative positions of the breast and the X-ray imaging apparatus are analyzed based on the confirmation image. It is possible to adjust the relative position of the imaging device and the top plate, adjust the number of rotations and elevation of the X-ray imaging device, and adjust the geometric arrangement of the X-ray generator and X-ray detector. . In order to check the relationship between the breast and the apparatus and adjust the alignment and imaging range, etc., low-dose X-rays with a small exposure dose can be used. Further, instead of using X-rays, optical imaging means can be used.
The top plate portion is provided with pressure detection means for two-dimensional detection, and detects the pressure that the subject presses against the top plate in the form of a pressure distribution having a two-dimensional spread, and a pressure adjuster and By controlling the pusher moving device, it is possible to retract the sternum and ribs that are excessively pushed out by the pusher.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a partial sectional perspective view conceptually showing a breast tomography apparatus according to an embodiment of the present invention. FIG. 2 is a plan view of a mammography bed of the breast tomography apparatus according to this embodiment. FIG. 3 is a plan view of the imaging unit, and FIG. 4 is a system block diagram illustrating the overall configuration of the breast tomographic imaging apparatus.

  As shown in FIGS. 1 and 2, the breast tomography apparatus 100 according to the present embodiment includes an opening 23 through which the breast passes, and the subject 10 can lie down and hang the breast 11 from the opening 23. Mammography bed provided with a top plate 20, an X-ray generator 41 that emits X-rays, and an incident intensity of X-rays that have been emitted from the X-ray generator 41 and transmitted through the breast 11 hanging from the opening 23 are detected. And an X-ray detector 42 having an FPD in which a plurality of X-ray detection elements are arranged on the surface, and a pressing unit 30 that abuts against the back of the prone subject 10 and presses downward.

  The mammography couch includes a top plate lifting device 21 that adjusts the height of the top plate 20 and a top plate translation device 22 that adjusts the position of the top plate 20 in two horizontal directions. The top plate elevating device 21 and the top plate translation device 22 are provided with a known appropriate drive mechanism, and can be automatically driven by a control signal input from the outside. The opening 23 through which the breast 11 passes may be only one object to be inspected, or two openings 23 are provided on the left and right sides, and the left and right breasts are passed from the beginning of the inspection, and the object is switched and inspected. May be. Note that the top plate translation device 22 of the breast tomographic imaging apparatus 100 that can be examined by switching between the left and right is a X-ray generator 41 and an X-ray generator 41 that replace the breast 11 that has been newly examined when the breast to be examined is switched left and right. It is necessary to have a stroke sufficient to move to the position of the rotation axis of the line detector 42.

  The top plate 20 has an appropriate ergonomic shape so that the subject 10 can lie down and project the breast 11 as much as possible from the opening 23. Moreover, it is preferable that the opening 23 can select an opening diameter and a shape according to the size of the breast 11. The opening 23 is preferably formed of a material such as silicon resin whose shape changes according to the shape of the breast 11. Further, an X-ray shielding part 25 is formed around the opening 23 so as to protrude from the surroundings, so that parts other than the breast 11 are not easily exposed to X-rays. Further, the X-ray beam radiated from the X-ray generator 41 does not direct X-rays in the direction of the top plate 20 on which the subject 10 lies. In addition, a planar pressure detection device 24 is installed around the opening 23 to monitor whether the subject 10 exhibits an abnormal pressure or abnormal pressure distribution on the chest due to the pressure received from the pressing unit 30. Has been.

  As shown in FIG. 3, the X-ray generator 41 and the X-ray detector 42 are opposed to an imaging unit rotating device 43 that rotates around a vertical rotating shaft passing through the opening 23 with the rotating shaft interposed therebetween. A necessary number of X-ray transmission images are taken at a predetermined timing while rotating around the breast 11 mounted and disposed in the vicinity of the rotation axis. When the breast 11 exceeds the X-ray irradiation range or the measurement range of the X-ray detector 42, the imaging unit elevating device 44 lowers the set of the X-ray generation device 41 and the X-ray detector 42 together to acquire the imaging range. Can be moved to the tip of the breast 11. The X-ray generator 41 and the X-ray detector 42 include an X-ray generator translation device 45 and an X-ray detector translation device 46, respectively, and change the distance from the breast 11 to be measured to change the image enlargement ratio. The shooting range can be adjusted by changing.

  The pressing unit 30 is configured such that the pressing device 31 having the buffer member 32 attached to the contact surface can be moved by the pressing unit lifting / lowering device 33 and the pressing unit translation device 34. After the subject 10 lies on the top plate 20 with the pressing device 31 lifted and hangs the breast 11 from the opening 23 onto the imaging region, as illustrated in FIG. The pressing device 31 is lowered so that the pressing device 31 hits the back of the subject 10 via the buffer member 32. Further, the pressing unit lifting / lowering device 33 is operated to press the breast 11 until the breast 11 is sufficiently exposed to the imaging range. The pressing device 31 is preferably segmented so that the pressure applied to each segment can be controlled independently. Furthermore, when the most effective compression position differs from the characteristics of the subject 10, the pressing device translation means 34 can be driven to move the pressing device 31 to the optimal position. In addition, it is preferable that the pressing device 31 is provided with a safety mechanism that does not excessively press the back of the subject 10.

  FIG. 6 is a side view showing another type of pressing portion that can be used in this embodiment. Instead of adjusting the pressing force of the pressing device 31 using the pressing unit lifting / lowering device 33, a separate independent pressing force adjusting device 35 may be provided as shown in FIG. The housing portion of the pressing force adjusting device 35 is fixed relative to the pressing portion lifting device 33, and the mandrel fixed integrally with the pad of the pressing device 31 moves up and down with respect to the housing portion. Thus, the pressing force of the pressing device 31 pressing the subject's back is adjusted.

  FIG. 7 is a conceptual diagram showing the operating principle of another type of pressing force adjusting device. As the pressing force adjusting device, for example, a method of pushing a piston using air pressure can be used. In the method using air pressure, an air pressure source is required. However, adjustment of the pressing force is easy, and an excessive load can be easily prevented due to the mechanism. For example, as shown in FIG. 7, a piston corresponding to the pressing device 31 is accommodated in a cylinder 36, and pressurized air from a pressurized air source (not shown) is supplied to the cylinder upper space via a pressure adjustment valve 37. The pressure of the piston is regulated by the air pressure in the cylinder determined by the pressure adjustment valve 37. Further, if the air escape hole 38 is provided at the excessive stroke position, the piston as the pressing device 31 cannot be physically pressed any more, so that it is safe for the subject.

The breast tomography apparatus 100 further includes a control device that controls the movements of the top board 20 and the imaging unit rotation device 43 and the operations of the X-ray generation device 41 and the X-ray detector 42. A display device is provided.
Referring to FIG. 4, the breast tomographic imaging apparatus 100 includes an image generation unit 110, an image processing unit 120, an image storage unit 130, an image display unit 140, an imaging unit 160, a top plate unit 170, and a pressing unit 180. .

  Specifically, the image generation unit 110 includes an X-ray generation unit 113 corresponding to the X-ray generation device 41 displayed in FIG. 1 and an X-ray detection unit 115 corresponding to the X-ray detector 42. When the trigger signal is received, the X-ray generation means 113 emits X-rays, and the X-ray detection means 115 detects the X-rays transmitted through the breast 11 as the subject to generate an X-ray transmission image signal and generate an image processing unit. 120.

The image processing unit 120 includes an image processing unit 121, an image correction unit 123, an image reconstruction unit 125, a confirmation image generation unit 127, and an adjustment value calculation unit 129.
The image processing unit 121 generates an image signal of an X-ray transmission image detected by the X-ray detection unit 115 based on the detection signal input from the image generation unit 110. The generated image signal is transmitted to the image correction unit 123 and also transmitted to the image storage unit 130 and the image display unit 140, and can be referred to as acquired image information.

The image correcting unit 123 corrects the acquired original image signal by removing noise and reducing artifacts, and transmits the corrected image to the image reconstruction unit 125 and the confirmation image generating unit 127.
When the image signals from each direction acquired for the subject are collected, the image reconstruction unit 125 performs a reconstruction operation to generate an image signal for forming the CT screen of the subject, and the image storage unit 130 and the image display To the unit 140.

The confirmation image generation unit 127 generates a confirmation image used for adjustment of the apparatus 100 and sends it to the adjustment value calculation unit 129. An image that shows the positional relationship between the screen and the subject is generated and related to the adjustment values of the device, such as whether the alignment is correct, whether it has the correct resolution, and does not include extra noise. Confirm.
The adjustment value calculation means 129 calculates an adjustment value necessary for eliminating the deviation from the expected value for the position of the screen frame, the signal intensity, and other environmental values, and the photographing unit control means 161 and the top panel control means. 171 and the pressing unit control means 181.
The adjustment value can also be designated directly by the operator via the adjustment value input means 151. The adjustment value input unit 151 includes a data input device using a keyboard, a touch panel, or a mouse.

The image storage unit 130 is provided with image storage means 131 formed by an image memory or the like, and can be easily read and used when image information is required.
The image display unit 140 is provided with an image display unit 141 and a confirmation image display unit 143. The image display unit 141 displays a breast cross-sectional image, a stereoscopic image, or the like as an image used for diagnosis. The confirmation image display unit 143 displays an image that can be used to monitor or adjust the abnormality or malfunction of the breast tomography apparatus 100. In particular, when the adjustment is performed by the operator, it is necessary to make an adjustment while observing the image displayed by the confirmation image display unit 143. The confirmation image generating means 127 displays the scale so that the adjustment amount can be easily calculated by imprinting a scale on the display screen or clearly indicating a numerical value that can determine the deviation from the target value in order to help the operator's judgment. It is preferable that

  The imaging unit 160 includes an imaging unit rotation unit 163 controlled by the imaging unit control unit 161, an imaging unit lifting / lowering unit 165, an X-ray detection unit translation unit 167, and an X-ray generation unit translation unit 169. The imaging unit 111 that has driven the image generation unit 110 supplies a trigger signal to the imaging unit control unit 161 every time the imaging procedure proceeds, and the imaging unit rotation unit that corresponds to the imaging unit rotation device 43 displayed in FIG. Then, the rotation and height of the X-ray generation means 113 and the X-ray detection means 115 are adjusted to the next determined positions via the imaging part raising / lowering means 165 corresponding to 163 and the imaging part raising / lowering device 44. Further, by using the X-ray detection unit translation unit 167 and the X-ray generation unit translation unit 169, the X-ray detection unit 115 which is the X-ray detector 42 and the X-ray generation unit 113 which is the X-ray generation device 41 or the subject. The detection sensitivity can be adjusted by adjusting the distance to a certain breast 11, that is, the rotation axis.

The top plate 170 includes a top plate translation unit 173, a top plate elevating unit 175, and a pressure detection unit 177 controlled by the top plate control unit 171. The top plate translation unit 173 and the top plate lifting unit 175 correspond to the top plate translation device 22 and the top plate lifting device 21 shown in FIG. The position of the X-ray bundle irradiated to the breast 11 can be easily adjusted by raising and lowering the imaging unit rotating device 43. However, since it is in a relative relationship, by adjusting the height by raising and lowering the top plate 20 Is also possible. Further, when making a diagnosis by switching the left and right breasts, it is necessary to reset the position of the new breast 11 to the rotation axis of the imaging unit rotating device 43 at the time of switching. In particular, when the top plate 20 is provided with two openings 23 corresponding to the left and right breasts, the other opening 23 is translated to the position of the rotation axis for alignment.
The pressure detection means 177 is a pressure detector 24 that is installed around the opening 23 as shown in FIG. 2 and detects pressure and pressure distribution. The pressure detector 24 senses the pressure distribution applied by the pressing unit 30 in response to the pressure received from the chest wall of the subject 10. The measurement result of the pressure detection unit 177 is transmitted to the pressing unit control unit 181 and used for controlling the pressing unit 31.

  The pressing unit 180 includes a pressing unit 183, a pressing unit translation unit 185, and a pressing unit lifting / lowering unit 187 controlled by the pressing unit control unit 181. Specifically, the pressing unit 180 is configured by the pressing unit 30 shown in FIG. 1 so that the pressing device 31 having the buffer member 32 attached to the contact surface can be moved by the pressing unit lifting device 33 and the pressing unit translation device 34. Is. After the subject 10 lies on the top plate 20 and hangs the breast 11 from the opening 23 to the imaging region, the pressing device 31 is applied to the back of the subject 10 via the buffer member 32, and the pressing portion The lifting device 33 is operated and pressed. Then, the chest of the subject 10 is pressed against the opening 23, the chest wall advances, the breast 11 is pushed out, and the base part of the breast 11 is entered into the imaging region. Since breast cancer also occurs in the vicinity of the chest wall, it is convenient for diagnosis that the root portion can be observed.

  However, since the sternum and ribs absorb X-rays easily and the influence of exposure cannot be ignored, it is desirable to avoid exposure as much as possible. Therefore, by detecting the positions where the sternum and ribs are reflected and pushing the chest to the limit where the chest wall is not included in the imaging region, the balance between the expansion of the examination region and the suppression of exposure is achieved. In addition, it is necessary to manage so that the pressure by the pressing unit 30 does not go too far and the chest wall is exposed to the X-ray irradiation region or the spine and sternum are extremely deformed and do not cause pain to the subject 10. . For this reason, the measurement result of the pressure detector 24 is monitored, and when an abnormality occurs, the pressing portion 30 is immediately raised or the pressurization is released so that safety can be ensured.

  FIG. 8 is a flowchart showing a process example when a target X-ray transmission image is acquired using the breast tomography apparatus 100 of the present embodiment. In the first stage S01, when the subject 10 climbs on the top board 20 and becomes prone and drops the breast 11 into the opening 23 of the top board 20, the breast 11 becomes the X-ray generator 41 and the X-ray detector. It hangs down near the rotation axis between 18 and falls within the imaging area. The opening 23 can be selected to have a size and shape that best fits the breast 11 having a different size and shape depending on the subject 10. Moreover, it is preferable that the opening part 23 is a raw material which changes a breast shape, such as a silicone resin. The subject 10 is protected by a shielding member 25 so that portions other than the breast 11 are not exposed to X-rays.

  In the next second stage S02, the pressing device 31 is pressed from the back side of the subject 10 via the buffer member 32. The pressing device 31 is segmented and can control the pressing force independently for each place. Therefore, in the third step S03, as a result of the pressing device 31 pressing the back of the subject 10, the chest wall portion of the subject 10 comes into contact with the pressure detector 24 to transmit the pressure to the subject 10. The pressing effect is detected as a pressure distribution. In the fourth stage S04, the pressing force of the pressing device 31 is controlled based on the measurement result by the pressure detector 24. When there is a deviation in the pressure distribution, the desired pressure and pressure distribution are realized by adjusting the pressing position or changing the pressing force for each segment. By correctly depressing with the pressing device 31, a range sufficient for diagnosis from the nipple to the chest wall boundary portion can be arranged in the imaging region, and the body movement of the subject can be suppressed to suppress the variation of the breast. The pressure distribution measured by the pressure detector 24 is displayed on a monitor so that the operator can observe it. In addition, it is preferable to determine the setting range so that the pressing force of the pressing device 31 cannot be set beyond a range that does not cause pain to the subject.

Next, it is determined whether a sufficient range of breasts for diagnosis is within the imaging range. Therefore, in the fifth step S05, X-ray simple imaging with a low dose is performed and image data of an X-ray transmission image is supplied to the determination device. Instead of X-ray imaging, optical image capturing may be performed with a light source (not shown) and a CCD camera, and determination may be made based on the outer shape. In the sixth step S06, the acquired captured image is used to determine whether the nipple serving as the lower boundary and the chest wall serving as the upper boundary are appropriately within the capturing region. This determination is performed by the determination unit configuring the adjustment value calculation unit 129 using image analysis or the like, but may be performed by an operator. For this reason, it is preferable to display the X-ray transmission image and the optical image on the confirmation image display means 143 so that the operator can observe.
An appropriate imaging range can be determined by checking the position of the marker affixed or applied to the surface of the breast 11 of the subject 10 on the screen. When using low-dose X-rays, the shadows of the ribs and sternum can be used as markers.

  If it is determined in the sixth step S06 that the necessary area of the breast 11 is not included in the imaging range, the process proceeds to a seventh step S07, and the relative position between the breast 11 and the imaging device 40 is set so that the imaging range is appropriate. adjust. Adjustment of the relative position of the top plate 20 and the imaging device 40 can be performed using either the top plate elevating device 21 or the imaging unit elevating device 44. If the breast 11 is large and does not fit within the imaging range, the X-ray transmission image is acquired while shifting the imaging device 40, and the relative position adjustment amount between the top 20 and the imaging device 40 and the X-ray imaging device 40. The number of rotations is calculated and imaging is performed while shifting from the base of the breast to the tip. In the case of a large breast that does not fit within the predetermined imaging range, the distance between the rotation axis of the X-ray imaging apparatus 40 where the breast 11 is located and the X-ray generation apparatus 41 or X-ray detector 42, that is, the geometrical arrangement is adjusted. As a result, the entire breast can fall within the imaging range.

The determination in the sixth step S06 and the adjustment in the seventh step S07 are preferably performed automatically by the breast tomography apparatus 100 itself, but may be determined manually by the operator. In order for the operator to make accurate judgments and adjustments, the confirmation image display means 143 has an auxiliary display that supports the evaluation of the amount of transition between the nipple or chest wall and the imaging range boundary and the calculation of the adjustment amount, such as a scale display. It is preferable. Further, the operator can manually input the adjustment amount via the adjustment value input means 151.
When it is determined in the sixth step S06 that the necessary area of the breast 11 is included in the imaging range, the process proceeds to an eighth step S08, and desired X-ray transmission image imaging is performed. The X-ray transmission image may be used for simple X-ray imaging or may be used for reconstruction as CT imaging.

  The breast tomography apparatus of the present invention pushes the back of the subject with a press while observing the relative position of the breast and the X-ray imaging apparatus based on the confirmation image, so that the breast can be pushed out to the chest wall region. Thus, it has become possible to perform image diagnosis over a wider range.

1 is a conceptual configuration diagram conceptually showing a breast tomographic imaging apparatus according to an embodiment of the present invention. It is a top view of the bed for mammography of the breast tomography apparatus concerning this embodiment. It is a top view of the imaging part in an embodiment. 1 is a system block diagram illustrating an overall configuration of a breast tomographic imaging apparatus according to an embodiment. It is a side view explaining an example of the press part raising / lowering apparatus in this embodiment. It is a side view which shows the press part of another type which can be used for this embodiment. It is a conceptual diagram which shows the operating principle of another type of pressing force adjustment apparatus in this embodiment. It is a flowchart showing the example of a process when acquiring the target X-ray transmission image using the breast tomography apparatus of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Subject 11 Breast 20 Top plate 21 Top plate elevating device 22 Top plate translating device 23 Opening portion 24 Pressure detecting device 25 Shielding portion 30 Pressing portion 31 Pressing device 32 Buffer member 33 Pressing portion elevating device 34 Pressing portion translating device 35 Pressing Pressure adjusting device 36 Cylinder 37 Pressure adjusting valve 38 Relief hole 40 Imaging unit 41 X-ray generating device 42 X-ray detector 43 Imaging unit rotating device 44 Imaging unit lifting device 45 X-ray generating unit translation device 46 X-ray detecting unit translation device 110 Image generation unit 111 Imaging unit 113 X-ray generation unit 115 X-ray detection unit 120 Image processing unit 121 Image processing unit 123 Image correction unit 125 Image reconstruction unit 127 Confirmation image generation unit 129 Adjustment value calculation unit 130 Image storage unit 131 Image storage Means 140 Image display unit 141 Image display means 143 Confirmation image display means 15 Adjustment value input unit 160 Imaging unit 161 Imaging unit control unit 163 Imaging unit rotation unit 165 Imaging unit elevating unit 167 X-ray detection unit translation unit 169 X-ray generation unit translation unit 170 Top plate unit 171 Top plate unit control unit 170 Top plate unit 171 Top plate control means 173 Top plate translation means 175 Top plate lift means 177 Pressure detection means 180 Press part 181 Press part control means 183 Press means 185 Press part translation means 187 Press part lift means 100 Breast tomographic imaging apparatus

Claims (15)

A top plate with an opening to suspend the breast when the subject prone,
A top plate moving device for horizontally moving the top plate portion;
A pressing device including a pad that is placed above the opening and presses the back of the subject lying on the top plate, and a pressing adjuster that adjusts the pressing of the pad;
A mammography bed provided with a pusher moving device for moving the pad relative to the subject;
An X-ray imaging apparatus in which an X-ray generator and an X-ray detector are arranged to face each other with a rotation axis perpendicular to the top plate part interposed therebetween;
An imaging device rotating device for rotating the X-ray imaging device;
An imaging apparatus lifting apparatus for moving the X-ray imaging apparatus relative to the top plate portion;
A breast tomographic imaging apparatus comprising: the top plate moving apparatus; and an adjustment value calculating apparatus that outputs an adjustment value to the imaging apparatus lifting apparatus.   The X-ray generator generates X-rays with a dose lower than usual, and the image generated by the X-ray detector is used as a confirmation image, and the adjustment value calculation device uses the breast and the X based on the confirmation image. The breast tomographic imaging apparatus according to claim 1, wherein an adjustment value is generated by analyzing a relative position of the X-ray imaging apparatus, and a relative position between the X-ray imaging apparatus and the top plate is adjusted based on the adjustment value.   The X-ray generator generates X-rays with a dose lower than usual, and the image generated by the X-ray detector is used as a confirmation image, and the adjustment value calculation device uses the breast and the X based on the confirmation image. The breast tomography according to claim 1, wherein the relative position of the X-ray imaging apparatus is analyzed to generate an adjustment value, and the number of rotations of the X-ray imaging apparatus and the elevation relative to the top plate portion are adjusted based on the adjustment value. apparatus.   The X-ray generator generates a lower dose of X-rays than usual, and the image generated by the X-ray detector is used as a confirmation image. The breast tomographic image according to claim 1, wherein an adjustment value is generated by analyzing a relative position of the X-ray imaging apparatus, and a geometric arrangement of the X-ray generation apparatus and the X-ray detector is adjusted based on the adjustment value. Shooting device.   The X-ray imaging apparatus includes an optical imaging unit, and the adjustment value calculation apparatus analyzes the relative position between the breast and the X-ray imaging apparatus based on a confirmation image generated by the optical imaging unit, and adjusts the adjustment value. The breast tomographic imaging apparatus according to claim 1, wherein a relative position between the X-ray imaging apparatus and the top plate is adjusted based on the adjustment value.   The X-ray imaging apparatus includes an optical imaging unit, and the adjustment value calculation apparatus analyzes the relative position between the breast and the X-ray imaging apparatus based on a confirmation image generated by the optical imaging unit, and adjusts the adjustment value. The tomographic image imaging apparatus according to claim 1, wherein the number of rotations of the X-ray imaging apparatus and the elevation relative to the top plate portion are adjusted based on the adjustment value.   The X-ray imaging apparatus includes an optical imaging unit, and the adjustment value calculation apparatus analyzes the relative position between the breast and the X-ray imaging apparatus based on a confirmation image generated by the optical imaging unit, and adjusts the adjustment value. The breast tomography apparatus according to claim 1, wherein a geometrical arrangement of the X-ray generator and the X-ray detector is adjusted based on the adjustment value.   The breast tomographic imaging apparatus according to any one of claims 2 to 7, wherein the adjustment value calculation apparatus analyzes a marker attached or applied to the breast as an index.   The breast tomographic imaging apparatus according to any one of claims 2 to 4, wherein the adjustment value calculation apparatus analyzes the chest wall portion of the subject imaged in the confirmation image as an index.   The breast tomography apparatus according to any one of claims 2 to 9, further comprising a display device that displays the confirmation image.   The breast tomographic image according to any one of claims 2 to 9, further comprising a display device for displaying the confirmation image, and displaying an index for measuring an adjustment amount of a relative position between the breast and the imaging device. Shooting device.   The top plate portion includes pressure detection means for two-dimensionally detecting the pressure that the subject presses against the top plate, and the pressure adjuster according to the two-dimensional pressure detected by the pressure detection means and The breast tomography apparatus according to any one of claims 1 to 11, which controls the pusher moving device.   The breast tomography apparatus according to claim 12, wherein the two-dimensional pressure detected by the pressure detection means is displayed on a display device.   The breast tomography apparatus according to claim 1, wherein the opening can be selected in size and shape.   The breast tomography apparatus according to claim 1, wherein the opening is formed of a material whose shape changes.

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