System and method for measuring deflection of a foam breast compression paddle

Abstract

A method of imaging a breast compressed with a foam paddle includes emitting X-ray energy from an X-ray source toward the breast, and the foam paddle has a plurality of upper markers and a plurality of lower markers, wherein the plurality of lower markers are movable relative to the upper markers. Detecting the X-ray energy from the X-ray source at a detector disposed opposite the breast. Generating an image of the compressed breast based on the detected X-ray energy. Identifying at least one of the plurality of upper markers and at least one of the plurality of lower markers in the image. Determining a thickness of the compressed breast at a plurality of thickness locations, wherein each thickness location of the plurality of thickness locations corresponds to at least one of the plurality of lower markers.

Description

[0001] Cross-references to related applications

[0002] This application, filed as a PCT international patent application on March 22, 2021, claims the benefit of priority to U.S. Provisional Patent Application Serial No. 63 / 000,790, filed on March 27, 2020, the entire disclosure of which is incorporated herein by reference. Background Technology

[0003] A known challenge in mammography and breast tomography synthesis is the potential discomfort patients may experience when the breast is compressed (which must be done with sufficient force to stabilize the breast and disperse breast tissue for X-ray imaging). Discomfort can potentially cause patient movement, negatively impacting image quality. Discomfort can also potentially deter patients from undergoing breast cancer screening. Another known challenge is ensuring the imaging field includes the desired amount of breast tissue. This discomfort has led to the development of compression paddles with flexible features, such as plastic sheets, flexible mesh, foam compression materials, etc. These flexible materials present unique challenges for accurate breast imaging. In existing imaging systems using flat, rigid compression plates, the thickness of the compressed breast can be determined fairly easily by measuring or calculating the height of the compression plate above the breast support platform. However, using flexible materials to stabilize the breast makes this simple calculation impossible. Summary of the Invention

[0004] In one aspect, the technology relates to a method for imaging a breast compressed with a foam paddle, the method comprising: emitting X-ray energy from an X-ray source toward the breast and a foam paddle having a plurality of upper and lower marks, wherein the plurality of lower marks are movable relative to the upper marks; detecting the X-ray energy from the X-ray source at a detector deployed opposite to the breast; generating an image of the compressed breast based on the detected X-ray energy; identifying at least one of the plurality of upper marks and at least one of the plurality of lower marks in the image; and determining the thickness of the compressed breast at a plurality of thickness locations, wherein each of the plurality of thickness locations corresponds to at least one of the plurality of lower marks. In one example, determining the thickness includes calculating a distance in the image between a first upper mark among the plurality of upper marks and a first lower mark among the plurality of lower marks adjacent to the image. In another example, determining the thickness includes determining a characteristic of at least one of the plurality of lower marks in the image. In yet another example, determining the thickness includes calculating a distance between a first upper mark among the plurality of upper marks and a second upper mark among the plurality of upper marks in the image. In still another example, determining the thickness includes calculating a distance between a first lower mark among the plurality of lower marks and a second lower mark among the plurality of lower marks in the image.

[0005] In another example of the above aspects, the X-ray energy includes scout exposure. In yet another example, the method also includes calculating automatic exposure control based at least in part on a determination of the thickness. In still another example, the method includes emitting imaging X-ray energy based at least in part on the calculated automatic exposure control.

[0006] In another example of the above aspects, the method includes modeling the difference between at least two of a plurality of thickness locations; and applying attenuation to the image based at least in part on the modeled difference.

[0007] In another example of the foregoing aspects, the method includes performing a tomographic synthesis imaging process; obtaining a set of tomographic synthetic images of a compressed breast from the tomographic synthesis imaging process; and identifying breast boundaries in at least one tomographic synthetic image of the tomographic synthetic image set. In this example, the identification of breast boundaries is based at least in part on the determination of thickness. In yet another example, the method includes displaying at least one tomographic synthetic image of the tomographic synthetic image set; and displaying features indicating breast boundaries on at least one tomographic synthetic image of the displayed tomographic synthetic image set. In still another example, the at least one tomographic synthetic image displayed includes the uppermost tomographic synthetic image of the breast.

[0008] In another example of the above aspects, the method includes calculating the X-ray imaging dose based at least in part on the determination.

[0009] In another example of the above aspects, the method includes processing an image; identifying at least one reference marker of at least one of a plurality of upper markers and a plurality of lower markers; applying a negative signal to the identified reference marker, wherein the application produces a corrected image; and displaying the corrected image. In another example, applying the negative signal includes adjusting the pixel count at the identified reference marker.

[0010] In another aspect, the technology relates to a paddle for compressing a breast, the paddle comprising: a foam profile including an upper surface, a lower surface, and a front wall; a plurality of upper marks disposed near the upper surface, wherein the plurality of upper marks are disposed at a first distance from the front wall; and a plurality of lower marks disposed near the lower surface, wherein the plurality of lower marks are disposed at a second distance from the front wall. In one example, the paddle includes a rigid substrate, wherein the foam profile is fixed to the rigid substrate at the upper surface, and wherein the plurality of upper marks are disposed between the rigid substrate and the foam profile. In another example, the plurality of lower marks are disposed within the foam profile. In yet another example, the plurality of marks are configured to move when the lower surface of the paddle is subjected to an upward force. In yet another example, the plurality of upper marks are configured to remain stationary when the lower surface of the paddle is subjected to an upward force. In yet another example, the paddle includes a bottom foam profile fixed to the foam profile, wherein the plurality of lower marks are disposed between the bottom foam profile and the foam profile. Attached Figure Description

[0011] Figure 1A This is a schematic diagram of an exemplary imaging system.

[0012] Figure 1B yes Figure 1A A perspective view of the imaging system.

[0013] Figure 2A-2C These are various views of a breast compression paddle with a foam compression element.

[0014] Figure 2D yes Figure 2A-2C A front view of a breast compression paddle.

[0015] Figure 3A and 3B A partial side view of an imaging system with a paddle, which utilizes a foam compression element and is marked thereon, is depicted.

[0016] Figure 4A A partial side view of an imaging system with a paddle is depicted, which utilizes a foam compression element and is marked thereon, in an uncompressed position.

[0017] Figure 4B Depicting Figure 4A A top view of the paddle in its uncompressed position.

[0018] Figure 5A Depicting Figure 4A A partial side view of the imaging system in the compressed position.

[0019] Figure 5B Depicting Figure 5A A top view of the paddle in the compressed position.

[0020] Figure 6 illustrates a method for imaging a breast compressed with a foam paddle.

[0021] Figure 6A A method for calculating automatic exposure control using breast thickness calculations performed in the method shown in Figure 6 is described.

[0022] Figure 6B A method for equalizing compressed breast images using breast thickness calculations performed in the method shown in Figure 6 is described.

[0023] Figure 6C A method for identifying the breast boundary of a compressed breast is described using breast thickness calculations performed in the method shown in Figure 6.

[0024] Figure 6D A method is described that uses the breast thickness calculation performed in Figure 6 to calculate the X-ray imaging dose for imaging a compressed breast.

[0025] Figure 6E A method for reducing marker artifacts in images of compressed breasts is described using breast thickness calculations performed in the method shown in Figure 6.

[0026] Figure 7 Examples depict suitable operating environments in which one or more of the given examples can be implemented.

[0027] Figure 8 Examples of networks in which the various systems and methods disclosed herein can be operated are depicted. Detailed Implementation

[0028] Using paddles made of foam compression material reduces patient discomfort during imaging, which can persuade more women to have regular checkups, leading to earlier cancer diagnoses. This improved comfort also reduces patient movement during imaging, resulting in better image outcomes. However, the breast shape produced by a paddle made of foam compression material differs significantly from that produced by a conventional rigid paddle. More specifically, the resulting compressed breast does not have a uniform thickness across the entire field of view when compressed with a foam compression element. Therefore, while paddles using foam compression elements are more comfortable, they present numerous challenges to how breast imaging systems (e.g., mammography, tomography, or combined mammography / tomography systems) expose and produce diagnostically relevant quality images.

[0029] The techniques described in this paper provide a method for accurately measuring the localized breast and foam thickness beneath a foam-compressed material across the entire field of view. This technique considers systems and methods for measuring localized thickness at discrete locations beneath the paddle. Knowing the breast thickness information for the entire breast allows for more accurate calculation of automatic exposure control (AEC) and X-ray dose. Furthermore, image processing and display can be improved. In the former example, the lack of uniform breast thickness due to the use of foam compression elements results in uneven X-ray images after standard image processing, making image review more difficult for radiologists. In the latter specific example, accurate measurement of breast thickness allows for the determination of breast boundaries, potentially excluding areas outside the boundaries (e.g., in discrete images of a tomographic composite image set) from subsequent review. Therefore, these techniques are crucial for the fabrication of viable paddles using foam-compressed materials.

[0030] Figure 1A This is a schematic diagram of an exemplary imaging system 100. Figure 1B This is a perspective view of imaging system 100. Also refer to... Figure 1A and Figure 1B The imaging system 100 fixes a patient's breast 102 for X-ray imaging (either mammography or tomography) via a breast compression fixation unit 104, which includes a static breast support platform 106 and a movable compression paddle 108. The breast support platform 106 and the compression paddle 108 each have compression surfaces 110 and 112, which move toward each other to compress and fix the breast 102. In known systems, the compression surfaces 110 and 112 are exposed for direct contact with the breast 102. The platform 106 also houses an image receiver 116 and an optional tilting mechanism 118, as well as an optional anti-scattering grid. The fixation unit 104 is positioned in the path of an imaging beam 120 emanating from an X-ray source 122, such that the beam 120 strikes the image receiver 116.

[0031] A fixation unit 104 is supported on a first support arm 124, and an X-ray source 122 is supported on a second support arm 126. For mammography, support arms 124 and 126 can rotate as units about axis 128 between different imaging orientations, such as CC and MLO, so that system 100 can acquire mammographic projection images in each orientation. In operation, image receiver 116 is held in place relative to platform 106 while acquiring images. Fixation unit 104 releases breast 102 so that arms 124, 126 move to different imaging orientations. For tomography, support arm 124 remains in place, with breast 102 fixed and held in place, while at least the second support arm 126 rotates X-ray source 122 about axis 128 relative to fixation unit 104 and compressed breast 102. System 100 acquires multiple tomographic projection images of breast 102 at various angles of beam 120 relative to breast 102.

[0032] Simultaneously and optionally, the image receiver 116 can tilt relative to the breast support platform 106 and in synchronization with the rotation of the second support arm 126. The tilt can be at the same angle as the rotation of the X-ray source 122, but can also be at different selected angles, such that each image beam 120 in multiple images remains substantially in the same position on the image receiver 116. The tilt can be about an axis 130, which may, but does not necessarily, lie in the image plane of the image receiver 116. A tilting mechanism 118 coupled to the image receiver 116 can drive the image receiver 116 with tilting motion. For tomography and / or CT imaging, the breast support platform 106 can be horizontal, or can be at an angle to the horizontal, for example, in an orientation similar to that of conventional MLO imaging in mammography. System 100 can be entirely a mammography system, a CT system, or entirely a tomography system, or a “combined” system that can perform multiple forms of imaging. Examples of such combined systems have been provided by the assignee of this document under the trade name Selenia Dimensions.

[0033] When the operating system is active, the image receiver 116 generates imaging information in response to the illumination of the imaging beam 120 and provides it to the image processor 132 for processing and generation of a mammogram. The system control and workstation unit 138, including software, controls the operation of the system and interacts with the operator to receive commands and transmit information including the processed X-ray image.

[0034] One challenge with the imaging system 100 is how to fix and compress the breast 102 for the desired or required imaging. Healthcare professionals (typically X-ray technicians) typically adjust the breast 102 within the fixator unit 104 while pulling tissue toward the imaging area and moving the compression paddle 108 toward the breast support platform 106 to fix the breast 102 and hold it in place, with as much breast tissue as possible between the compression surfaces 110, 112. This can cause patient discomfort.

[0035] To improve patient comfort, compression paddles utilizing foam compression materials have been developed. Compression paddles utilizing foam compression materials are generally described in PCT international patent applications filed May 24, 2019, No. PCT / US2019 / 033998, No. PCT / US2019 / 034001, and No. PCT / US2019 / 034010, the disclosures of which are incorporated herein by reference in their entirety. Such paddles stabilize and gently compress the breast while reducing the discomfort associated with compression paddles that only have a rigid compression surface.

[0036] Figure 2A-2C Various views are shown of an example of a breast compression paddle 200 having a foam compression element 202 fixed to a rigid substrate 204. (The description also includes...) Figure 2A-2C The paddle 200 includes a bracket portion 206, which is generally integrally formed with the substrate 204 for connecting the paddle to the compression arm of the imaging system. The paddle 200 also includes a front surface 208 opposite the bracket portion 206, which is arranged close to the patient's chest wall during compression and imaging. In this example, the substrate may be rigid. As used herein, the term "rigid" does not mean that the substrate 204 does not bend during breast compression, but rather that the substrate 204 exhibits greater resistance to bending or deformation than the foam compression element 202 attached to the bottom of the substrate 204. A raised wall 204a provides additional rigidity.

[0037] The foam compression element 202 can be secured to the bottom surface of the substrate 204 using a chemical adhesive. In other examples, the upper surface of the compression element can be a rigid plastic or other material to which the foam compression element 202 is secured. Such rigid plastic can be attached to the rigid substrate 204 of the paddle 200 using multiple bolts, hooks, or other mechanical fasteners (not shown). If such mechanical fasteners are used, it may be desirable to position them outside the area of ​​the foam compression material 202 intended to be compressed against the breast, thereby avoiding pressure points and the resulting discomfort, as well as preventing artifacts in any generated X-ray images.

[0038] The foam compression element 202 includes multiple edge surfaces. A leading edge surface 210 is arranged near the front surface 208 of the substrate 204 to be close to the patient's chest wall during compression and imaging. A trailing edge surface 212 is arranged opposite the leading edge surface 210, near the support portion 206. Side edge surfaces 214, 216 are also depicted. Generally, these side edge surfaces 214, 216 can be depicted as inner or outer side edge surfaces, consistent with the terms commonly used to describe the inner and outer sides of the breast. Of course, those skilled in the art will recognize that the same compression paddle 200 can be used to compress either breast one at a time, which would effectively change the application of the terms "inner" and "outer" to the side edge surfaces of the foam compression material 202. Furthermore, a midplane 220 is arranged between the side edge surfaces 214, 216 at their approximate midpoint. The midplane 220 is arranged substantially orthogonal to the compression surface 218 arranged on the underside of the foam compression material 202. Portions of the compression surface 218 will contact the breast during compression. In another example, the foam compression material 202 may be covered with a biocompatible covering that protects the foam compression material 202 from absorbing bodily fluids. In this example, it may be disposable or washable. To improve the patient experience, the covering may be made of a soft material where it contacts the patient. To prevent fluid from transferring into the foam compression material 202, the opposing plastic side may contact the foam compression material 202. Interface 222 is located where the compression surface 218 meets the leading edge surface 210. The shape of interface 222 during compression helps define the foam compression material 202 and its function.

[0039] Figure 2D This is a front view of a compression system 250 used in an imaging system. The compression system 250 includes a first compression element in the form of a compression paddle 200, having a rigid base plate 204 and a foam compression element 202 fixed thereto. A second compression element, in this case a breast support platform 252, is also depicted. A breast 254 rests on the upper surface 256 of the breast support platform 252. During use, the breast 254 is compressed by a force F applied by the compression paddle 200. As compression increases, the foam compression material 202 deforms and conforms to the contour of the breast 254. Thus, both the breast 254 and the foam compression material 202 are compressed as the force F increases. This compression can be defined by the percentage of compression of the foam compression material 202 near the mid-plane 220 at the leading edge surface 210 when the breast 254 is substantially centered along the mid-plane 220. In other examples, the contour of the interface 222 may define the compression of the foam compression material 202.

[0040] As described above, the foam compression material 202 has an uncompressed height H at its front edge surface 210. In one example, the uncompressed height H at the front edge surface 210 can be approximately one inch to approximately two inches. In another example, the uncompressed height H can be approximately two inches to approximately three inches. In yet another example, the uncompressed height H can exceed approximately three inches. Testing has determined that an uncompressed height H of approximately three inches is sufficient to compress a large number of breasts, from small to large. Prior to the tomographic imaging process, the breast 254 can be compressed to an imaging state, in this example, a state that allows the breast to be sufficiently stabilized and slightly compressed. Unlike previous systems that used rigid compression paddles resulting in significant flattening of the breast, this compressed breast imaging state only requires a manageable amount of thickness for the resulting tomographic images. Such a manageable amount can be a diagnostically meaningful amount, allowing the resulting breast image slices to provide sufficient differentiation between slices, but without such a large number of images, this would require significantly more review time for clinicians.

[0041] In the example, this imaging state of the breast 254 is achieved before the foam compression material 202 at the front edge surface 210 is fully compressed. Figure 2D The maximum amount of foam compression material required to compress the breast 254 to an imaging state is depicted. For illustrative purposes, Figure 2D A breast 254 is depicted centered on the midplane 220 of the foam compression material 202. Therefore, a portion of the foam compression element 202 at this location is not fully compressed, and... Figure 2D The height H' is depicted as the incompletely compressed height. This incompletely compressed height H' is the portion of the foam compression material 202 measured at the leading edge surface 210. Although it represents the most compressed portion of the foam compression material 202, it can still be further compressed if further force is applied to the breast 254. In the example, imaging conditions for the breast are achieved when only a portion of the foam compression material 202 reaches the fully compressed height H'. This fully compressed height H' changes (i.e., increases) with increasing distance from the chest wall. This is a result of the breast shape and the properties of the foam compression material.

[0042] The shape of interface 222 can define the compression of the foam compression material 202. Unlike prior art thin foam pads where the interface between the compression surface and the leading edge surface is substantially flattened along the entire length of the breast, the foam compression material 202 of this technology maintains a curved shape along most of the entire breast 254. Interface 222 defines, for example, a generally smooth curvature 256 from a first contact point 258 near the inner side of the breast 254 to a second contact point 260 near the outer side of the breast 254. However, prior art thin foam pads are almost flat from the first contact point to the second contact point.

[0043] Figure 3A and 3B A partial side view of an imaging system 300 with a paddle 302 is depicted. The paddle 302 utilizes a foam compression material 304 and has multiple markings thereon. The multiple markings arranged in multiple rows above and below the foam compression material 304 (as described in more detail herein) allow for the detection of uneven thickness in the compressed breast. Unless otherwise stated, Figure 3A and 3B The suffixes depicted correspond to specific features described in the figures without the suffixes. Each paddle 302 includes a rigid substrate 308 and a foam compression material 304 fixed to its bottom surface. In the figures, the rigid substrate 308 is depicted spaced apart from the foam compression material 304, but this is for illustrative purposes only. Fixed between the rigid substrate 308 and the foam compression material 304 are a plurality of top marks arranged in rows parallel to the breast wall. The first row of top marks 306 is depicted closest to the breast wall, for example, close to the front surface of the rigid substrate 308 and the foam compression element 304. The second row of top marks 310 is deployed at a first distance d1 from the first row 306, and the third row of top marks 312 is deployed at a second distance d2 from the second row 310. Top marks 306, 310, and 312 can be fixed to the rigid substrate 308 or the foam compression material 304 and can be deployed between those elements. In another example, the top marks can be deployed on the upper surface of the rigid substrate. At these locations, top markings 306, 310, and 312 primarily indicate the level of the top surface of the foam compression material 304 and the bottom surface of the rigid substrate 308. Top markings 306, 310, and 312 serve as fixing references.

[0044] Attached to the bottom surface of the foam compression material 304 are a plurality of bottom marks arranged in rows parallel to the breast wall. The first row of bottom marks 314 is depicted closest to the breast wall, for example, at a third distance d3 from the front surfaces of the foam compression element 304 and the rigid substrate 308. The second row of bottom marks 316 is positioned at a fourth distance d4 from the first row 314, and the third row of bottom marks 318 is positioned at a fifth distance d5 from the second row 316. The bottom marks 314, 316, and 318 may be exposed at the bottom of the foam compression material 304a, such as... Figure 3A As shown, or it can be covered by a thin foam covering 320b, such as Figure 3BAs shown in the diagram. The thin foam covering 320b may be formed of the same or different material as the foam compression material 304, and may be approximately 5%, approximately 7%, approximately 10%, approximately 12%, approximately 15%, or approximately 17% of the thickness of the foam compression material 304. In this location, the bottom markings 314, 316, and 318 primarily indicate the level of the top surface of the compressed breast or the bottom surface of the foam compression material 304 (for the portion of the foam compression material 304 that does not contact the breast).

[0045] Distances d1, d2, d3, d4, and d5 allow each of the rows 306, 310, 312, 314, 316, and 318 to be visible in the resulting image generated from the emission from the X-ray tube (its focal point is plotted at 320). Therefore, given the angle of the X-ray energy 322, the second bottom row marker 316 remains visible in the resulting image due to the spacing distance d2 between the second top row marker 310 and the third top row marker 312. Distances d1, d2, d3, d4, and d5 can be determined at least in part based on the thickness of the foam compression material 304, the length of each marker in each row (described in more detail herein), the expected distance between the focal point 322 and the markers, and other factors.

[0046] Figure 4A A partial side view of an imaging system 400 with a paddle 402 is depicted, which utilizes a foam compression element 406 and has markings thereon, in an uncompressed position. Figure 4B Depicting Figure 4A A top view of the paddle 402 in its uncompressed position. During imaging, all markings appear on a single depicted plane. Simultaneously described... Figure 4A and 4B As is known in the art, the foam compression material 406 is fixed to the rigid substrate 404 and is movably positioned relative to the breast support platform 408. Rows are depicted with top markings 410, 412, 414, each of which includes a plurality of discrete lines, scale lines, or other markings of known dimensions and spacing. For example, each line in each row 410, 412, 414 has a known length l. T Furthermore, the distances between adjacent rows 410, 412, and 414 are also known. Rows marked with bottom labels 416, 418, and 420 are also depicted, and each includes numerous discrete lines, tick marks, or other markings with known dimensions and intervals. For example, each line in each row 410, 412, and 414 has a known length l. B Furthermore, the distances between adjacent rows 410, 412, and 414 are also known. When an X-ray image of paddle 402 is taken, the distances between adjacent rows (e.g., ...) are also known. Figure 4BThe distance (drawn in the resulting image) can be identified as D. Here, the distance D is not necessarily the same across all projections of all rows, but is used for illustrative purposes only.

[0047] Figure 5A Depicting Figure 4A A partial side view of the imaging system 400 in the compressed position. Figure 5B Depicting Figure 5A A top view of the image of propeller 402 in the compressed position. During imaging, all markings appear on a single depicted plane. Simultaneously described... Figure 5A and 5B . Figure 4A and 4B Some of the components depicted in the text are also Figure 5A and 5B The description is provided and therefore need not be further elaborated. The foam compression material 406 presses the breast B against the breast support platform 408. During compression, the top markings 410, 412, and 414 typically maintain their position and projected length l. T However, as the foam compression element 406 changes shape to fit the contour of the compressed breast B, this compression alters one or both of the positions and projected lengths of the bottom markings 416, 418. Then, in Figure 5B In the projection, these changes are depicted as the interval distance D' between adjacent projection rows. Here, the distance D' between all projections of all rows is not necessarily the same, but is used for illustrative purposes only. However, note that since the position of marker row 420 does not change (because it is not located on the deflected portion of the foam compression material 406), the interval distance with the adjacent top marker row 414 is the same as... Figure 4B The spacing in the middle remains unchanged. Furthermore, the projected lengths of the bottom marker rows 416 and 418 also change due to the variation in the curvature of the foam compression material (this changed projected length is depicted as l'). B Since the marker line 420 is not located on the deflection portion of the foam compression material 406, its length remains l. B Given these variations in marker length and marker spacing, geometric calculations allow the system to determine the curvature of the foam compression material 406, and thus determine information about the thickness of the breast beneath each marker.

[0048] It can be recognized that if Figure 4A and 5A The length l of the mark depicted in the middle T l B The interval distance D is known, and the length l' of the imaging marker is known. T 、l' BSince the spacing distance D' is measured in the X-ray image, triangulation can produce the distances between the actual markers 410-420 and the imaging plane. The distances between markers 410, 412, 414 and the bottom of the rigid substrate 404, and the distance between the imaging plane and the top of the breast platform, are known. By measuring the spacing distances between adjacent rows of projected markers (e.g., top row 410 and bottom row 416), and the lengths of the bottom rows 416, 418, 420, the deflection of the bottom surface of the foam compression material 406 can be determined. These various calculations are used to calculate the geometric thickness of the compressed breast B at numerous locations to generate the profile of the compressed breast. Techniques for calculating the thickness of a breast compressed by a rigid paddle are described in U.S. Patent No. 8,768,026, the disclosure of which is incorporated herein by reference in its entirety. These techniques solve the problem of measuring the spacing distances between adjacent markers in a single row to determine the breast paddle height, thereby determining the breast thickness. These techniques are applicable to determining the distances of the top markers 410, 412, 414 above the breast support platform.

[0049] It has been discovered that the method described in U.S. Patent No. 8,768,026 can be modified and applied to calculate the interval distances D and D' between adjacent imaging rows, and the length l of discrete markers in the rows. T l B 、l' B These calculations allow us to determine the breast thickness at multiple discrete points on the foam compression material.

[0050] More generally, Figure 6 depicts a method 600 for imaging a breast compressed with a paddle having a flexible compression element such as a foam compression material. Method 600 begins in operation 602, where X-ray energy is emitted from an X-ray source toward the breast and the foam paddle. The foam paddle can be configured as depicted elsewhere herein and includes at least a plurality of upper markers and a plurality of lower markers. The lower markers are movable relative to the upper markers because they are deployed near the lower surface of the foam paddle, while the upper markers remain fixed because they are typically deployed near a rigid substrate of the foam paddle. In operation 604, the X-ray energy from the X-ray source is detected at a detector deployed opposite the breast (e.g., below a breast support platform). This detection can be a single detection (e.g., in the context of a standard mammographic exposure or a reconnaissance image exposure) or multiple detections may occur (e.g., in the context of a tomographic synthesis process). In operation 606, an image of the compressed breast is generated based on the detected X-ray energy. In operation 608, at least one of the plurality of upper markers and at least one of the plurality of lower markers is identified in the image generated in operation 606.

[0051] When this method 600 is used in a tomographic synthesis imaging process, it can be applied to each tomographic projection image to perform thickness analysis. In this respect, method 600 can be applied to 2D images generated during standard mammography, as well as individual 2D images acquired during the tomographic synthesis imaging process. However, during tomography, another analytical method can be used to obtain thickness information. Each slice can be examined, and slices with stronger marker signals can be identified. The number of slices in the slice stack allows for the determination of the slice height, which can be used to calculate the vertical (e.g., Z-axis) position of the top and bottom markers. By identifying the slice with the strongest marker signal, the marker will appear in several slices rather than a single slice, but the slice with the strongest signal corresponds to the vertical position of that slice in the Z-axis.

[0052] Returning to method 600, operation 610 can determine the thickness of the compressed breast at multiple thickness locations. Each of the multiple thickness locations corresponds to at least one of a plurality of subscripts. By determining the thickness of the breast (e.g., the height of the top of the breast above the breast platform), a complete contour of the upper surface of the breast can be generated.

[0053] Method 600 describes multiple operations for calculating breast thickness. In some examples, typically only a single operation of these operations is needed to determine breast thickness. However, multiple operations are generally desired to improve the accuracy of the generated contour, leading to performance improvements and more accurate calculations in downstream processing (described further herein). In the context of determining or calculating the image distance between upper markers (e.g., a distance depicted in an X-ray image), operation 618 is used to determine the height of the upper markers (the rigid substrate deployment near the paddle), as described in U.S. Patent No. 8,768,026, the entire disclosure of which is incorporated herein by reference. This calculation provides baseline or reference information about the height of the rigid portion of the paddle and can be used in conjunction with other calculations described herein. Breast thickness at discrete locations can be calculated based on the determination or calculation of one or both of the characteristics of the markers (e.g., operation 612) and the spacing between two markers (e.g., operation 614). For example, determining thickness may include calculating the length of at least one of a plurality of lower markers in the image, operation 612a. Since the length of the markers is known, variations in that length (as reflected in the image) can help determine the amount of deformation of the foam compression element. This deformation will cause the individual markers to appear shorter in the resulting image. In operation 612b, the resulting pattern of the markers can be determined and compared with a known pattern of the markers. For example, if the markers are dashed lines and the frequency of the dashed lines changes in the resulting image, then the deflection of that portion of the foam compression material can be determined.

[0054] Regarding the calculation of distances in an image, operation 614 describes several calculations or determinations. In operation 614a, determining the thickness includes calculating the interval distance between a first upper marker among a plurality of upper markers and a first lower marker among a plurality of lower markers adjacent to the image. Here, the term "adjacent to the image" is used to indicate that the upper and lower markers will appear in the same two-dimensional image, even if they are located at different heights of the paddle. A change in the interval distance from a known interval distance (e.g., when the paddle is uncompressed) indicates that the lower marker has moved relative to the upper marker. Based on this information, geometric calculations can be performed to correlate the change in the interval distance with a change in the height of the second marker. In operation 618b, determining the thickness includes calculating the distance between a first upper marker among a plurality of upper markers and a second upper marker among a plurality of upper markers in the image. Again, this is described in U.S. Patent No. 8,768,026. In operation 614c, determining the thickness includes calculating the interval distance between a first lower marker among a plurality of lower markers and a first lower marker among a plurality of lower markers in the image. The significant variation in the spacing indicates that multiple submarkers are at different elevations, and therefore, that one part of the breast has a different thickness than another. Once the thickness is determined, further methods can be performed to properly image the breast, generate images for display, eliminate artifacts, etc., as described below.

[0055] Figure 6A A method 630 is depicted for calculating automatic exposure control (AEC) using the breast thickness calculation performed in method 600 of Figure 6. The calculation of automatic exposure control requires breast thickness as input. Operation 632, for example, obtains the breast thickness calculation from method 600. In method 630, the breast thickness can be calculated in method 600 based on the reconnaissance exposure (e.g., the emitted X-ray energy). Based on the thickness, operation 634 calculates the AEC. When calculating the AEC of a non-uniformly compressed breast, one or more factors can be utilized or considered. In one example, the volume of the breast (which can be calculated based on a defined breast contour) can be considered. In another example, the breast thickness at a specific location (e.g., near the chest wall or near the nipple) can be considered. In yet another example, the average thickness of the breast over its region can be considered. In yet another example, the AEC can be calculated for one or more discrete portions of the breast (e.g., near the chest wall, nipple, or one or more other locations). Those obtained AECs can also be considered or weighted to determine the AEC of the entire breast. In the examples, a variety of considerations can be utilized. Once the AEC is known, subsequent imaging X-ray emission (e.g., standard mammography and / or tomographic synthesis scan) can be emitted, operation 636. The dose of the subsequent X-ray emission is based at least in part on the calculated automatic exposure control.

[0056] Figure 6BA method 640 is described to equalize an image of a compressed breast using the breast thickness calculation performed in method 600 of Figure 6. When the breast under compression does not have a uniform thickness, the resulting X-ray image will be uneven after standard image processing. This unevenness can make it difficult to review mammograms, as breast images need to appear flat to correctly identify lesions. Generally, few (if any) efficient image processing methods can flatten images of breasts with irregular thickness. However, if the breast thickness distribution is known (e.g., via method 600 of Figure 6), then the physical thickness variation of the breast can be modeled. The breast image can then be compensated using additional tissue attenuation. The resulting breast image will appear as if the breast has a uniform thickness. Known image processing algorithms can then be used to generate diagnostically relevant images for review. In method 640, the breast thickness can be calculated in method 600 and obtained from it, operation 642. Based on the thickness varying across the entire breast, the breast contour can be constructed. The difference in breast thickness at at least two locations with different thicknesses can be modeled, operation 644. The model used determines which parts of the breast should be attenuated (and by how much) to flatten the appearance of the breast in the image. Based on the differences in the modeling, the attenuation can be applied to the breast, operation 646.

[0057] Figure 6CMethod 650 is described to identify the breast boundaries of a compressed breast using breast thickness calculations performed in method 600 of Figure 6. In a tomographic synthetic image set, the last slice reconstructing the breast volume often lacks a clear indication of the breast boundaries due to limited Z-axis resolution. This problem is exacerbated when using a paddle with foam compression elements, as the physical breast boundaries can be located on more than one slice (in fact, often affecting several slices). Since the proposed technique accurately measures the breast thickness within the field of view, this thickness information can be used to identify the breast boundaries. The breast volume boundaries in each reconstructed slice can be digitally labeled using additional software. This helps save time for image stack reviewers (e.g., clinicians), as they no longer need to review slice portions deployed outside the breast volume. In method 650, the breast thickness can be calculated in method 600 and obtained from it, operation 652. In operation 654, a tomographic synthetic imaging process is performed. In one example, the tomographic synthetic imaging process performed can be the X-ray energy emitted as operation 602 of method 600. In another example, the tomographic synthetic imaging process can be separated from it. In operation 656, a set of tomographic synthetic images of the compressed breast is obtained from the tomographic synthetic imaging process. In operation 658, the breast boundary is identified in at least one tomographic synthetic image of the set of tomographic synthetic images; typically, determined at least in part based on thickness, the boundary will be identified in multiple slices, usually one or more of the uppermost slices. In the example, the boundary can be identified by comparing the breast thickness at multiple discrete locations with the various generated slices. The thickness at these multiple discrete locations corresponds to the upper contour or vertical boundary of the breast (e.g., the uppermost skin surface). Therefore, all portions of the slice located outside the breast thickness at each particular location can be excluded from further processing and / or display. In operations 660 and 662, the display of the slice(s) and breast boundary is performed, respectively. Specifically, in operation 660, at least one tomographic synthetic image of the set of tomographic synthetic images is displayed. In operation 662, features indicating the breast boundary are displayed on the displayed tomographic synthetic image(s). The boundary can be a line, contour line, or curve surrounding the relevant area. In other examples, all areas outside the breast boundary can be obscured, covered, or otherwise deformed. In another example, the portion of the image outside the breast boundary can be completely removed from the display.

[0058] Figure 6DA method 670 is described, which uses the breast thickness calculation performed in method 600 of Figure 6 to calculate the X-ray imaging dose for imaging a compressed breast. Without breast thickness as input, the X-ray radiation dose cannot be calculated correctly. In method 670, the breast thickness can be calculated in method 600 and obtained from it, operation 672. In operation 674, the X-ray imaging dose can be calculated based on it. In the example, a dose correction factor can be applied, or the dose can be based on local thickness (e.g., a specific portion near the breast), or the dose can be based on a calculated average of the entire breast thickness, based on area.

[0059] Figure 6E A method 680 is described to reduce marker artifacts in an image of a compressed breast by utilizing breast thickness calculation performed in method 600 of Figure 6. In method 680, markers are selected such that they are invisible in a normal breast image and only become visible after supplementary image processing. After image processing, the intensity of the upper and lower markers and their positions in the image are known. A negative marker signal can then be added to the image to make the image markers artifact-free. This is particularly important for the quality control images of the system. In method 680, breast thickness can be calculated in method 600 and obtained from it, operation 682. In operation 684, the image is processed via known processing techniques. In operation 686, at least one reference marker of at least one of a plurality of upper and a plurality of lower markers is identified in the image. In operation 688, a negative signal is applied to the identified reference marker; this application produces a corrected image. In an example, the negative signal may correspond to an adjustment of the pixel count at the identified marker location, operation 690. These identification and application operations can be performed on the entire image to effectively remove marker artifacts. In other examples, markers located only within the breast boundary (e.g., such as...) Figure 6C The image identified in method 650 can be identified in this way. In operation 692, the corrected image is displayed.

[0060] Figure 7An example of a suitable operating environment 700 in which one or more of the given examples may be implemented is illustrated. This operating environment may be directly incorporated into the imaging system disclosed herein, or it may be incorporated into a computer system separate from the imaging and compression system described herein but used to control the imaging and compression system described herein. This is merely one example of a suitable operating environment and is not intended to imply any limitation on the scope of use or functionality. Other well-known computing systems, environments, and / or configurations suitable for use include, but are not limited to, imaging systems, personal computers, server computers, handheld or laptop devices, multiprocessor systems, microprocessor-based systems, programmable consumer electronics such as smartphones, network PCs, minicomputers, mainframe computers, tablet computers, distributed computing environments including any of the foregoing systems or devices, etc.

[0061] In the most basic configuration of the operating environment 700, at least one processing unit 702 and a memory 704 are typically included. Depending on the exact configuration and type of computing device, the memory 704 (which, among other things, stores instructions for calculating breast thickness, determining X-ray dose, or performing other methods disclosed herein) may be volatile (such as RAM), non-volatile (such as ROM, flash memory, etc.), or some combination of both. Figure 7 The most basic configuration is illustrated by dashed line 706. Furthermore, environment 700 may also include storage devices (removable device 708 and / or non-removable device 710), including but not limited to magnetic or optical discs or tapes. Similarly, environment 700 may also have one or more input devices 714, such as touchscreens, keyboards, mice, pens, voice input, etc., and / or one or more output devices 716, such as displays, speakers, printers, etc. Environment may also include one or more communication connections 712, such as LAN, WAN, peer-to-peer, Bluetooth, RF, etc.

[0062] Operating environment 700 typically includes at least some form of computer-readable medium. Computer-readable medium can be any available medium accessible by processing unit 702 or other devices having an operating environment. By way of example and not limitation, computer-readable medium can include computer storage media and communication media. Computer storage media includes volatile and non-volatile, removable and non-removable media implemented using any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical storage devices, magnetic cartridges, magnetic tape, disk storage devices or other magnetic storage devices, solid-state storage devices, or any other tangible medium that can be used to store desired information. Communication media implements computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and includes any information delivery medium. The term "modulated data signal" refers to a signal having one or more characteristics set or altered in a manner that encodes information in the signal. By way of example and not limitation, communication media include wired media such as wired networks or direct wired connections, and wireless media such as acoustic, RF, infrared, and other wireless media. Any combination of the above should also be included within the scope of computer-readable media. A computer-readable device is a hardware device incorporating computer storage media.

[0063] The operating environment 700 can be a single computer operating in a networked environment using a logical connection to one or more remote computers. The remote computers can be personal computers, servers, routers, network PCs, peer-to-peer devices, or other public network nodes, and typically include many or all of the above-mentioned components as well as other components not mentioned. The logical connection can include any method supported by a communication medium. Such networked environments are common in offices, enterprise-wide computer networks, intranets, and the Internet.

[0064] In some embodiments, the components described herein include modules or instructions executable by computer system 700, which may be stored on computer storage media and other tangible media and transmitted over communication media. Computer storage media include volatile and non-volatile, removable and non-removable media implemented with any method or technique for storing information such as computer-readable instructions, data structures, program modules, or other data. Any combination of the above should also be included within the scope of readable media. In some embodiments, computer system 700 is part of a network that stores data in remote storage media for use by computer system 700.

[0065] Figure 8This is an embodiment of network 800 in which the various systems and methods disclosed herein can be operated. In this embodiment, a client device, such as client device 802, can communicate with one or more servers (such as servers 804 and 806) via network 808. In this embodiment, the client device can be a standalone imaging system including all the functions described herein (e.g., Figure 1A The imaging system 120 depicted in the image. Client devices may also include or be combined with laptops, personal computers, smartphones, PDAs, netbooks, or any other type of computing device, such as... Figure 7 The computing device in the example. In this example, such a client device can be connected to an imaging system. In the embodiment, servers 804 and 806 can also be any type of computing device, such as... Figure 7 The computing device shown. Network 808 can be any type of network capable of facilitating communication between client devices and one or more servers 804 and 806. For example, surface image data and interior image data can be acquired locally via an imaging system and transmitted to another (or more) computing devices for further processing, such as an image acquisition workstation or a cloud-based service. Examples of such networks include, but are not limited to, LANs, WANs, cellular networks, and / or the Internet.

[0066] In embodiments, the various systems and methods disclosed herein may be executed by one or more server devices. For example, in one embodiment, a single server, such as server 804, may be used to execute the systems and methods disclosed herein, such as the imaging methods discussed herein. Client device 802 may interact with server 804 via network 808. In another embodiment, client device 802 may also perform the functions disclosed herein, such as scanning and image processing, which may then be provided to server 804 and / or 806.

[0067] This disclosure describes some examples of the technology with reference to the accompanying drawings, which show only a few possible examples. However, other aspects may be implemented in many different forms and should not be construed as limited to the examples set forth herein. Rather, these examples are provided to make this disclosure thorough and complete, and to fully convey the scope of possible examples to those skilled in the art.

[0068] While specific examples are described herein, the scope of this technology is not limited to those specific examples. Those skilled in the art will recognize other examples or modifications within the scope of this technology. Therefore, specific structures, actions, or media are disclosed only as illustrative examples. Unless otherwise stated herein, elements or components generally disclosed but not explicitly illustrated can also be combined according to the examples of this technology. The scope of this technology is defined by the appended claims and any equivalents thereof.

Claims

1. A method for imaging a breast compressed with a foam paddle, the method comprising: X-ray energy is emitted from an X-ray source toward the breast and the foam paddle, the foam paddle having multiple upper and multiple lower markings, wherein the multiple lower markings are movable relative to the upper markings; The X-ray energy from the X-ray source is detected at a detector deployed opposite to the breast; An image of a compressed breast is generated based on the detected X-ray energy; Identify at least one of the plurality of upper marks and at least one of the plurality of lower marks in the image; as well as The thickness of the compressed breast is determined at multiple thickness locations, each of the multiple thickness locations corresponding to at least one of the multiple subscripts.

2. The method of claim 1, wherein determining the thickness includes calculating the distance between a first upper marker of the plurality of upper markers and a first lower marker of an adjacent image of the plurality of lower markers in the image.

3. The method of claim 1, wherein determining the thickness includes determining the characteristics of at least one of the plurality of submarks in the image.

4. The method of claim 1, wherein determining the thickness includes calculating the distance between a first top marker and a second top marker among the plurality of top markers in the image.

5. The method of claim 1, wherein determining the thickness includes calculating the distance between a first sub-marker and a second sub-marker among the plurality of sub-markers in the image.

6. The method of claim 1, wherein the X-ray energy includes reconnaissance exposure.

7. The method of claim 6, further comprising calculating automatic exposure control based at least in part on the determination of thickness.

8. The method of claim 7, further comprising at least in part based on the calculated automatic exposure control emission imaging X-ray energy.

9. The method of claim 1, further comprising: Model the difference between at least two of the plurality of thickness locations; as well as Attenuation is applied to the image at least in part based on differences in modeling.

10. The method of claim 1, further comprising: Perform the tomographic synthetic imaging process; A set of tomographic synthetic images of the compressed breast is obtained from the tomographic synthetic imaging process; as well as Identify the breast boundary in at least one tomographic composite image from the set of tomographic composite images.

11. The method of claim 10, wherein identifying the breast boundary is based at least in part on the determination of thickness.

12. The method of claim 11, further comprising: Display at least one tomographic composite image from the set of tomographic composite images; as well as Features indicating breast boundaries are displayed on at least one tomographic composite image in the set of tomographic composite images shown.

13. The method of claim 12, wherein at least one tomographic image displayed includes a tomographic image of the uppermost part of the breast.

14. The method of claim 1, further comprising calculating the X-ray imaging dose based at least in part on the thickness of the determined compressed breast at a plurality of thickness locations.

15. The method of claim 1, further comprising: Process the image; At least one reference mark is identified among at least one of the plurality of upper marks and the plurality of lower marks; A negative signal is applied to the identified reference marker, wherein the application produces a corrected image; as well as The corrected image is displayed.

16. The method of claim 15, wherein applying the negative signal includes adjusting the pixel count at the identified reference marker.

17. A paddle for compressing a breast, the paddle comprising: Foam profile, including upper surface, lower surface and front wall; Multiple upper markers are deployed near the upper surface, wherein the multiple upper markers are deployed at a first distance from the front wall; as well as Multiple lower markers are deployed near the lower surface, wherein the multiple lower markers are deployed at a second distance from the front wall. The second distance is configured relative to the first distance such that the movement of one or more of the plurality of lower markers relative to the plurality of upper markers is measurable.

18. The paddle of claim 17, further comprising a rigid substrate, wherein the foam profile is fixed to the rigid substrate at the upper surface, and wherein the plurality of upper markings are disposed between the rigid substrate and the foam profile.

19. The paddle of claim 17, wherein the plurality of undermarks are deployed within the foam profile.

20. The paddle of claim 17, wherein the plurality of lower marks are configured to move when the lower surface of the paddle is subjected to an upward force.

21. The paddle of claim 20, wherein the plurality of upper markings are configured to remain stationary when the lower surface of the paddle is subjected to an upward force.

22. The paddle of claim 17, further comprising a bottom foam profile fixed to the foam profile, wherein the plurality of sub-markers are disposed between the bottom foam profile and the foam profile.

Images