Methods and systems for imaging breast tissue underneath implants

Abstract

Disclosed herein are methods and systems for x-ray imaging a breast and a breast implant in the breast simultaneously, comprising positioning the breast and the breast implant on a support platform of an x-ray imaging system, wherein an x-ray detector is disposed below the support platform. A high-energy x-ray is emitted through the breast and the breast implant, wherein the high-energy x-ray delivers a high-energy x-ray dose to the breast, and wherein the high-energy x-ray dose does not exceed a prescribed dose. The high-energy x-ray is received at the x-ray detector. The high-energy x-ray received at the x-ray detector is processed to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high-energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

Description

METHODS AND SYSTEMS FOR IMAGING BREAST TISSUEUNDERNEATH IMPLANTSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 677,200, filed July 30, 2024, which is incorporated by reference herein in its entirety.BACKGROUND

[0002] X-ray mammography has become the most commonly used tool for breast cancer screening, diagnosis, and evaluation in the United States. A mammogram is an x-ray image of inner breast tissue that is used to visualize normal and abnormal structures within the breasts. Mammograms provide early cancer detection because they can often show breast lumps (including tumors) and / or calcifications before they are manually palpable.

[0003] While screening x-ray mammography is recognized as the most effective method for early detection of breast cancer, there are challenges when performing x- ray mammography on patients with dense breasts or who have breast implants. An implant or dense region may obscure or partially obscure the tissue beneath (and / or above) it. An image with an implant can create a very large artifact in an image, sometimes obscuring almost an entirety of a breast image. Current procedures for imaging a breast with an implant include taking four extra images (two on each breast) in addition to other mammogram images. In these extra images, which are called implant displacement views, the implant is displaced toward the chest wall and the breast is pulled forward over it and then immobilized, allowing for better imaging of the breast tissue in front of the implant. This manipulation of the implant can be uncomfortable and even painful for the patient, especially if scar tissue has formed around all or part of the implant. These uncomfortable procedures may nevertheless result in mammography images that still have at least a portion of the breast tissue obscured by the implant, and do not provide a solution for other obscuring features, such as dense tissue.SUMMARY

[0004] Disclosed herein are systems and methods for imaging a breast and an implant within the breast simultaneously. A high-energy x-ray is emitted through both the breast tissue and the implant simultaneously. The high-energy x-ray is received at a detector, and the resulting processed image contains information allowing a user to identify features within the breast. These methods provide a method of imaging the breast with the implant in a manner that provides a usable image, does not require uncomfortable or painful manipulation of the implant out of the imaging field, and does not substantially increase the dose of radiation experienced by the patient. The disclosed systems and methods of imaging may also be useful for body parts other than the breast, where something is present (for example, dense tissue) that is obscuring the x-ray images.

[0005] According to examples of the present disclosure, a method of x-ray imaging a breast and a breast implant in the breast simultaneously comprises: determining that the implant is present in the breast; positioning the breast and the breast implant on a support platform of an x-ray imaging system, wherein an x-ray detector is disposed below the support platform; performing an automatic exposure control technique on the breast to determine a predetermined x-ray exposure dose, wherein determining the predetermined dose comprises: emitting a scout high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, and wherein the scout high-energy x-ray delivers a scout x-ray exposure to the breast; emitting an imaging high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein: the imaging high-energy x-ray delivers an imaging x- ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose; receiving the imaging high-energy x-ray at the x-ray detector; and processing the imaging high- energy x-ray received at the x-ray detector to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high-energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

[0006] In some examples, the method further includes receiving a selection of a region of interest within an area of the high-energy x-ray image defined by the breast implant.

[0007] In some examples, the selected region of interest corresponds to the breast tissue feature.

[0008] In some examples, the method further includes displaying the processed high-energy x-ray image.

[0009] In some examples, receiving the selection of the region of interest comprises receiving a user selection of the region of interest.

[0010] In some examples, emitting the imaging high-energy x-ray through the breast and the breast implant comprises performing a tomosynthesis imaging procedure.

[0011] In some examples, emitting the imaging high-energy x-ray through the breast and the breast implant comprises performing a mammography imaging procedure.

[0012] In some examples, the method further includes: emitting a low-energy x-ray through the breast and the breast implant, wherein the low-energy x-ray delivers a low- energy x-ray exposure to the breast, wherein the sum of the low-energy x-ray exposure, the scout x-ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose; receiving the low-energy x-ray at the x-ray detector; processing the low-energy x-ray received at the x-ray detector to obtain a low-energy x-ray image of the breast and the breast implant; and summing the high-energy x-ray image with the low-energy x-ray image to obtain a summed image.

[0013] In some examples, summing the high-energy x-ray image with the low- energy x-ray image comprises adding a first value of a pixel in the high-energy x-ray image to a second value of the pixel in the low-energy x-ray image.

[0014] In some examples, the method further includes collimating the imaging high-energy x-ray to emit the imaging high-energy x-ray primarily through the breast implant and portions of the breast above and below the breast implant.

[0015] In some examples, where the imaging high-energy x-ray is emitting during a first imaging modality procedure and wherein the method further comprises: emitting, during a second imaging modality procedure different than the first imaging modality procedure, a low-energy x-ray through the breast and the breast implant; and receiving the low-energy x-ray at the x-ray detector.

[0016] In some examples, the method further includes: displaying the high-energy x-ray image;

[0017] processing the low-energy x-ray received at the x-ray detector to obtain a low-energy x-ray image of the breast and the breast implant; and displaying the low- energy x-ray image.

[0018] In some examples, the scout high-energy x-ray is between about 49 kVp and 74 kVp and wherein the imaging high-energy x-ray is between about 49 kVp and 74 kVp.

[0019] In some examples, the automatic exposure control technique is performed by the x-ray imaging system.

[0020] According to an example of the present disclosure, a computing system comprises: at least one processor; and at least one memory storing computer-executable instructions for of x-ray imaging a breast and a breast implant in the breast simultaneously, the computer-executable instructions when executed by the at least one processor causing the computer to: based on the breast and the breast implant being positioned on a support platform of an x-ray imaging system, send an instruction to an x-ray source of the x-ray imaging system to emit a scout high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein the scout high-energy x-ray delivers a scout x-ray exposure to the breast; send a second instruction to the x-ray source of the x-ray imaging system to emit an imaging high- energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein: the imaging high-energy x-ray delivers an imaging x-ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose; receive the imaging high-energy x-ray at an x-ray detector, wherein the x-ray detector is disposed below the support platform; and process the imaging high-energy x-ray received at the x-ray detector to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high-energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

[0021] In some examples, the computing system further comprises instructions to transmit the high-energy x-ray image to a display of a review device.

[0022] In some examples, the computing system further comprises instructions to: based on the breast and the breast implant being positioned on the support platform, send a third instruction to the x-ray source to emit a low-energy x-ray through the breast and the breast implant, wherein the low-energy x-ray delivers a low-energy x-ray exposure to the breast, wherein the sum of the low-energy x-ray exposure, the scout x- ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose; and receive the low-energy x-ray at the x-ray detector, wherein processing the imaging high-energy x-ray further comprises summing the imaging high-energy x-ray receivedat the x-ray detector with the low-energy x-ray received at the x-ray detector to obtain the x-ray image.

[0023] In some examples, the computing system further comprises instructions to: collimate the imaging high-energy x-ray to emit the imaging high-energy x-ray primarily through the breast implant and portions of the breast above and below the breast implant.

[0024] In some examples, where the imaging high-energy x-ray is emitting during a first imaging modality procedure and where the computing system further comprises instructions to: send a third instruction to the x-ray source to emit, during a second imaging modality procedure different than the first imaging modality procedure, a low- energy x-ray through the breast and the breast implant; and receive the low-energy x- ray at the x-ray detector.

[0025] In some examples, the computing system further comprises instructions to: transmit the imaging high-energy x-ray image to a display of a review device; process the low-energy x-ray received at the x-ray detector to obtain a low-energy x-ray image of the breast and the breast implant; and transmit the low-energy x-ray image to the display of the review device.

[0026] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Non-limiting and non-exhaustive examples are described with reference to the following Figures.

[0028] FIG. 1 depicts a perspective view of an example imaging system.

[0029] FIG. 2 A depicts a partial enlarged view of the imaging system of FIG. 1.

[0030] FIG. 2B depicts a partial front view of the imaging system of FIG. 1.

[0031] FIG. 2C depicts a partial view and collimation beams of the imaging system ofFIG. 1

[0032] FIG. 3 depicts an example x-ray image of breast tissue with a displaced implant.

[0033] FIG. 4 depicts an example high-energy x-ray image of simulated breast tissue and an implant.

[0034] FIG. 5A depicts an example low-energy x-ray image of simulated breast tissue with an implant.

[0035] FIG. 5B depicts an example high-energy x-ray image of the simulated breast tissue with implant of FIG. 5 A.

[0036] FIG. 6 depicts a method of imaging a breast and a breast implant in the breast simultaneously.

[0037] FIG. 7A depicts an example low-energy x-ray image of simulated breast tissue.

[0038] FIG. 7B depicts an example high-energy x-ray image of the simulated breast tissue of FIG. 5 A.

[0039] FIG. 8 depicts an example graph of x-ray attenuation vs. energy, and associated table showing related peak voltage values.

[0040] FIG. 9 depicts an example of a suitable operating environment in which one or more of the present examples can be implemented.DETAILED DESCRIPTION

[0041] In the following detailed description, references are made to the accompanying drawings that form a part hereof, and in which are shown by way of illustrations specific embodiments or examples. These aspects may be combined, other aspects may be utilized, and structural changes may be made without departing from the present disclosure. Examples may be practiced as methods, systems, or devices. It should be understood that this invention is not limited to the particular methodology, protocols, and reagents, etc., described herein and as such may vary. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims and their equivalents.

[0042] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as those commonly understood to one of ordinary skill in the art to which this invention pertains. As used herein and in the claims, the singular forms “a,” “an”, and “the” include the plural reference unless the context clearly indicates otherwise.

[0043] Disclosed herein are systems and methods for imaging a breast and an implant within the breast simultaneously. A high-energy x-ray is emitted through both the breast tissue and the implant simultaneously. The high-energy x-ray is received at a detector, and the resulting processed image contains information allowing a user to identify features within the breast. These methods provide a method of imaging the breast withthe implant in a manner that provides a usable image, does not require uncomfortable or painful manipulation of the implant out of the imaging field, and does not substantially increase the dose of radiation experienced by the patient. The disclosed systems and methods of imaging may also be useful for body parts other than the breast, where something is present (for example, dense tissue) that is obscuring the x-ray images.

[0044] There are challenges when performing x-ray mammography or tomosynthesis on patients with dense breasts or who have breast implants. An implant or dense region may completely or partially obscure the tissue beneath it. This is a challenge for the current population of women, 50% of whom are considered to have dense breasts. Women with dense breasts are at a higher risk of developing breast cancer because the cancer may go undetected. In addition, women with dense breast may need to undergo additional imaging such as ultrasound or MRI to be able to detect any tissue obscured by the dense tissue.

[0045] Current procedures for imaging a breast with an implant include taking four extra images (two on each breast, resulting in additional radiation exposure) in addition to other mammogram images. In these extra images, which are called implant displacement views, the implant is displaced toward the chest wall and the breast tissue is pulled forward over the implant and then immobilized, allowing for better imaging of the breast tissue in front of the implant. This manipulation of the implant can be uncomfortable and even painful for the patient, especially if scar tissue has formed around all or part of the implant. These uncomfortable procedures may still result in mammography images that still have at least a portion of the breast tissue obscured by the implant, and do not provide a solution for other obscuring features, such as dense tissue.

[0046] As disclosed herein, a breast including an implant may be positioned on a gantry for imaging, such that the implant is within the imaging field. A high-energy x-ray (as defined below) is emitted through both the breast tissue and the implant simultaneously (without needing to push the implant out of the imaging field). The high-energy x-ray is received at a detector, and the resulting processed image contains information allowing a medical professional to identify features (for example, regions of interest) within the breast (for example, tumors, cysts, areas of infection or clotting, and / or other regions of interest within the breast). The technologies herein contemplate methods of imaging the breast with the implant in a manner that provides a usable image, reduces or eliminates uncomfortable or painful manipulation of theimplant out of the imaging field (or additional imaging such as implant displacement views), and does not substantially increase the dose of radiation experienced by the patient.

[0047] In some examples, an additional benefit of utilizing the high-energy x-ray as described herein is that it allows for the use of a minimum X-ray time (for example, about 25 ms or between about 10 and 30 ms), which may decrease the total time required for imaging by about 30 ms (for example, between 10 ms and about 40 ms).

[0048] A characteristic of the digital imaging systems disclosed herein is the ability to vary the amount and intensity of radiation used to generate images. Radiation intensity is related to the atomic number (Z) of the x-ray target, the x-ray current (mA), x-ray voltage (kilovoltage peak, kVp, also referred to as x-ray energy, beam energy, or simply “energy”), x-ray quantity (mAs), and x-ray beam filtration. Radiation intensity is varied to improve image quality, which in turn can improve diagnostic sensitivity. When radiation intensity increases, quantum mottle (image noise caused by photon absorption) tends to decrease and vice versa. Mammography and tomosynthesis systems may allow the operator to control x-ray exposure by manually setting technique factors such as mAs and kVp.

[0049] The average total absorbed dose (hereinafter “dose”) of radiation to the patient’s tissue during mammography is subject to regulatory limits for patient safety. In modalities where multiple images are taken, the regulated dose for a single exposure is the sum of the individual doses that the patient was exposed to for each image. There are several methods to calculate a dose, and the calculation may be performed by a medical specialist or a computing system. Commonly, dose is calculated as a mean glandular dose (MGD) measured in gray or milligray (Gy or mGy). The dose is estimated prior to performing imaging on a patient, and typically, the total dose must not exceed 2.5 mGy per exposure for a standard breast as regulated, for example, by the International Atomic Energy Agency and the European Union. MGD may be calculated by:

[0050] MGD = Kgcs Equation 1

[0051] In the above Equation 7, K equals an incident surface air kerma (the kinetic energy released in material, at the skin entrance plane). The factor g equals a conversion factor for a 50% glandular breast based on thickness of the breast and half-value layer (the thickness of the breast tissue at which the radiation intensity is halved). The variable c equals a correction factor for non-standard granularity based on thickness of the breast and half-value layer. The variable s equals a correction factor for the x- ray spectra based on the anode / target / filter combination in use. These values may be measured or calculated. Some factors that affect radiation dose received by the breast include: breast thickness and composition, x-ray beam energy (kVp), x-ray quantity (mAs), target / filter combination, and / or use of various different modes or grids.

[0052] There are several imaging technologies utilized for breast imaging. Breast mammography is a two-dimensional imaging technology that involves acquiring images of a stationary immobilized breast. In typical exams, one mammography projection image Mp is taken at a single angle of the imaging x-ray beam relative to the breast. Breast tomosynthesis is an imaging technology that involves acquiring images of a stationary immobilized breast at multiple angles during a short scan. These individual projection tomosynthesis images Tp taken at respective angles of the imaging x-ray beam relative to the breast are then computer-processed into a series of reconstructed tomosynthesis slice images Tr each representing a respective slice of the breast. The reconstructed tomosynthesis slice images Tr, together, represent thickness of the breast. The Tr images are typically displayed individually, concurrently, or in a dynamic mode.

[0053] In one example of tomosynthesis acquisition, an x-ray tube (x-ray source) moves in an arc above the breast and a series of low-dose x-ray 2D tomosynthesis projection images Tp is obtained. The sum of the dose from all of the 2D tomosynthesis projection images Tp is similar to the dose from a single conventional digital mammogram Mp. These low-dose 2D tomosynthesis projection images Tp are reconstructed into a series of tomosynthesis slice images Tr each representing a slice of the breast where each slice is, for example, 1-5 mm thick. The slice images Tr typically conform(s) to planes parallel to the platform supporting the breast during image acquisition, but may be oriented differently. When using tomosynthesis, by showing the breast as a series of slices rather than in a single mammogram image, a lesion may be seen with greater clarity because much of the superimposed tissue present in a conventional mammogram has been removed. Further, locating the lesion within the thickness of the breast may be more easily determined.

[0054] In some examples, general radiology techniques may be employed to image the implants and tissues as described herein.

[0055] In some examples, a low-energy x-ray energy (typical of mammography and tomosynthesis applications) is about 29 kVp. In an example, a low-energy x-ray energy is between about 24 kVp and about 35 kVp. In an example, a low-energy x-ray energy is between about 24 kVp and about 39 kVp. In an example, a low-energy x-ray energy is between about 24 kVp and about 29 kVp. In an example, a low-energy x-ray energy is between about 29 kVp and about 35 kVp. In an example, a low-energy x-ray energy is less than about 40 kVp. In an example, a low-energy x-ray energy is less than about 35 kVp. In an example, a low-energy x-ray energy is less than about 30 kVp. In an example, a low-energy x-ray energy is less than about 29 kVp. In an example, a low-energy x-ray energy is less than about 25 kVp.

[0056] In some examples, a high-energy x-ray energy (not previously typical of mammography and tomosynthesis applications, due to concerns of image quality / feature contrast as discussed further below regarding to FIGS. 7A, 7B, and 8) is about 49 kVp. In an example, a high-energy x-ray energy is between about 43 kVp and about 49 kVp. In an example, a high-energy x-ray energy is between about 35 kVp and about 49 kVp. In an example, a high-energy x-ray energy is between about 35 kVp and about 74 kVp. In an example, a high-energy x-ray energy is between about 49 kVp and about 74 kVp. In an example, a high-energy x-ray energy less than or equal to about 74 kVp. In an example, a high-energy x-ray energy is between about 40 kVp and about 49 kVp. In an example, a high-energy x-ray energy is at least about 35 kVp. In an example, a high-energy x-ray energy is at least about 40 kVp. In an example, a high- energy x-ray energy is at least about 43 kVp. In an example, a high-energy x-ray energy is at least about 49 kVp. In an example, a high-energy x-ray energy is at least about 50 kVp.

[0057] Some systems include an Automatic Exposure Control (AEC) functionality which controls a duration of administration of radiation, turning off the x-ray source when the desired dose has been administered. Automatic Exposure Control (AEC) methods may vary the dosing parameters, including exposure time, kVp, mAs, and / or filter modes for an image to vary the exposure and the radiation intensity.

[0058] Once an image acquisition mode and an acquisition process are identified, acquisition parameters and image processing techniques can be varied at a projection image granularity by varying at least one of kVp, mAs, and / or filter for each image capture or series of image captures.

[0059] To maintain a same or similar dose (for example, similar to a first dose that is an AEC calculated dose), if the x-ray energy in kVp is increased, the x-ray quantity in mAs may be decreased. The prescribed / predetermined dose is dependent at least in part on a thickness of the breast. In an example, a similar dose may be less than about 10% of an AEC predicted dose. In an example, a similar dose may be less than about 2% of an AEC predicted dose. In an example, a similar dose may be less than about 5% of an AEC predicted dose. In an example, a similar dose may be less than about 20% of an AEC predicted dose. In an example, a similar dose may be between about 2% and about 5% of an AEC predicted dose. In an example, a similar dose may be between about 5% and about 10% of an AEC predicted dose. In an example, a similar dose may be between about 10% and about 20% of an AEC predicted dose. In an example, a similar dose may be between about 5% and about 20% of an AEC predicted dose. In an example, a similar dose may be between about 2% and about 10% of an AEC predicted dose. In an example, a similar dose may be between about 2% and about 20% of an AEC predicted dose.

[0060] In typical and / or low-energy AEC determinations, the thickness of the breast (for example, including the implant) may be determined via positioning of a compression paddle. One or more scout shots (i.e. a short test exposure) that include(s) a low-energy x-ray exposure (for example, low-energy x-ray as defined above) may be performed at the determined thickness to measure tissue density and to ultimately determine optimum imaging settings and technique (in some examples, including an imaging vKp) which together define a resulting prescribed dosage to be used for one or more imaging shots / exposures. In some examples, a typical low-energy scout shot may be about 26kVp. The scout shot has an associated mAs that contributes to an overall dose delivered to the breast. However, when this low-energy AEC technique is applied to a thick breast, or to dense tissue, the mAs required for the scout shot contributes to a higher dose being associated with the scout shot. Additionally, when this low-energy AEC technique is applied to a tissue that includes an implant, the thickness may be determined including the implant, but the scout shot may be performed through tissue with the implant moved out of the way. The mAs required for the scout shot contributes to a higher dose being associated with the scout shot. Not only does this expose the tissue to additional dose, but it reduces the dose available from the prescribed / predetermined dose available for subsequent imaging shots, to avoid exposing the tissue to too high of a total dose. Further, a scout shot taken through tissue with an implant moved out of the way contributes to determined optimum imaging settings and techniques that cannot reliablyor clearly image through the implant (and therefore, features above or below the implant may be missed in the subsequent imaging shots).

[0061] In some examples (for example, where an implant is determined to be present within a breast), a high-energy AEC is performed (this high-energy AEC may be performed manually or automatically via the x-ray imaging system). The thickness of the breast (for example, including the implant) may be determined via positioning of a compression paddle. One or more scout shot(s) that include(s) a high-energy x-ray exposure (for example, high-energy x-ray as defined above) at a defined kVp may be performed (through both tissue and a dense region or implant) at the determined thickness to determine optimum imaging settings and technique (which define a resulting dosage). The scout shot has an associated mAs that contributes to an overall dose delivered to the breast. After the scout shot, an imaging shot (or multiple imaging shots or exposures) that includes a high-energy x-ray exposure (for example, a high- energy x-ray of the same energy as that used for the scout shot) may be performed on the breast. The imaging shot has an associated mAs that contributes to an overall dose delivered to the breast, however, only the dose associated with the imaging shot contributes to the image(s) that will be evaluated by medical personnel. The manual mode AEC prescribed / predetermined dose places a limit on the overall dose (i.e. sum of dose from the scout shot and the imaging shot(s)) that the patient / breast is exposed to.

[0062] The use of the manual mode AEC with a high-energy scout shot (for example, as applied to a tissue that includes an implant, to a thick breast, or to dense tissue) provides determination of imaging techniques and a prescribed / predetermined dose that ensures subsequent imaging shots will be able to identify features in the higher-density tissues (e.g. tissues including an implant). The use of the manual mode AEC with a high-energy scout shot also provides repeatability in imaging clarity for the scout shot(s). The mAs required for the high-energy scout shot contributes to a lower dose being associated with the scout shot (the mAs required for the high-energy scout shot may be lower than an mAs required for a low-energy scout shot as discussed above). Not only does this expose the tissue to a smaller dose, but it increases the dose available from the prescribed / predetermined dose available for subsequent imaging shots, to avoid exposing the tissue to too high of a total dose while providing for the ability to capture more images or higher energy images.

[0063] FIG. 1 depicts a perspective view of an example imaging system 100. FIG. 2A depicts a partial enlarged view of the imaging system 100. FIG. 2B depicts a partial front view of the imaging system 100. FIGS. 1, 2A, and 2B are described concurrently, and not all features may be shown in each of FIG. 1, FIG. 2A, and FIG. 2B. In the example, the imaging system 100 may include a gantry 102 and a data acquisition workstation 104. The gantry 102 includes a housing 106 supporting a tube arm unit 108 that includes a rotatable compression arm assembly 110 and a rotatable x-ray tube assembly 112. The compression arm assembly 110 enables a patient’s breast to be immobilized for x-ray imagining, such as either, or both, of mammography and tomosynthesis. The compression arm assembly 110 includes a compression paddle 114 and a receptor housing 116 disposed opposite the compression paddle 114. The receptor housing 116 has a compression surface 118 that directly contacts the breast during compression and immobilization. The receptor housing 116 encloses a detector subsystem 120 that includes an image receptor 122 and may include a retractable anti-scatter grid 124 (both shown in FIGS. 2A and 2B). The compression arm assembly 110 is in a path of an imaging beam that emanates from an x- ray source 126 housed in the x-ray tube assembly 112, such that the beam impinges in the image receptor 122. X-ray tube assembly 112 includes at least an x-ray tube (x-ray source) generating x-ray energy in a selected range, such as 20 to 50 kV, at mAs such as in the range 3-400 mAs, with focal spots such as a nominal size 0.3 mm large spot and nominal size 0.1 mm small spot. Also included may be supports for multiple x-ray filters such as molybdenum, rhodium, aluminum, copper, titanium, cesium iodide, silver and tin filters. An adjustable collimation assembly selectively collimating the x-ray beam may also be present. The collimation assembly may collimate the beam from the focal spot in a range such as from a 7 by 8 cm rectangle to a 24 by 29 cm rectangle when measured at the image plane of an x-ray image receptor 502 included in the system, at a maximum source-image distance such as 75 cm.

[0064] The housing 106 may also house and enclose a vertical travel assembly for moving the tube arm assembly 108 up and down to accommodate a particular patient or imaging position. An x-ray tube arm position mechanism rotates and / or positions the x-ray tube assembly 112 for different imaging positions. A compression arm position mechanism rotates and / or positions the compression paddle 114, image receptor 122, and the grid 124. Generally, the housing 106 includes any suitable motors and electrical and mechanical components and connections to implement these functions as discussed herein.

[0065] The workstation 104 may include a display (for example, a screen) 150 (typically a flat panel display that may include touch-screen functionality), user interface devices such as a keyboard, a mouse or trackball, and various switches and indicator lights and / or displays. The workstation 104 also includes computing facilities (e.g., hardware, firmware, and software) for controlling the gantry 102 and for processing, storing, and displaying data and images received from the gantry 102 during imaging operations. The gantry 102 and the workstation 104 may exchange data and controls of a schematically illustrated connection 136. In other examples, the gantry 102 and the workstation 104 may be integration in a single unit. A power source 138 may power the imaging system 100.

[0066] FIG. 2A is a partial enlarged view of the imaging system 100. FIG. 2B is a partial front view of the imaging system 100. Referring concurrently to FIGS. 2A and 2B, certain components of the imaging system of FIG. 1 are described above, and as such, are not necessarily described further. In operation, the imaging system 100 immobilizes a patient’s breast for x-ray imaging (either or both of mammography and tomosynthesis) via the compression arm assembly 110 that includes the static receptor housing 116 and the moveable compression paddle 114, both which are coupled to a support arm 140. The compression paddle 114 is configured to move M along the support arm 140 and toward the receptor housing 116 to compress and immobilize the breast. The compression paddle 114 is positionable and supported by a compression arm device 142 that is disposed at least partially within the support arm 140 and at least partially outside of the support arm 140. In some examples, the compression paddle 114 may also be configured to linearly translate T in relation to the compression arm device 142. The compression arm device 142 includes an external compression device assembly 144 that the compression paddle 114 can removably couple thereto. The compression device assembly 144 includes at least one rotatable knob 146, which can be utilized to move the compression paddle 114 as described herein. In the example, the compression arm device 142 may be a component of the compression arm position mechanism 132 (shown in FIG. 2A) that drives motion of the compression paddle 114.

[0067] For mammography or tomosynthesis, the compression arm assembly 110 and the x-ray tube assembly 112 can rotate as a unit about an axis 148 (shown in FIG. 2A) between different imaging orientations such as CC and MLO, so that the imaging system 100 can take a mammogram projection image at each orientation. In 2D mammography mode, the image receptor 122 remains in place relative to the receptor housing 116 while an image is taken. The compression arm assembly 110 can release thebreast for movement of one or more of the compression arm assembly 110 and the x-ray tube assembly 112 to a different imaging orientation. The vertical travel assembly and x- ray tube arm position mechanisms can make position adjustments to accommodate a patient and can rotate x-ray tube assembly 112 and compression arm assembly 110 together as a about a horizontal axis for different image orientations. For example, tube x-ray tube assembly 112 and compression arm assembly 110 can rotate between (-195 degrees) and (+150 degrees). Compression paddle 114 can move laterally, in a direction along the chest wall of a patient, to adjust for different imaging orientations. The compression paddle may comprise any one of a plurality of types of paddles, including but not limited to a full paddle, a spot paddle, a foam paddle, or a curved paddle, and may be configured to tilt against a spring bias and / or to move laterally.

[0068] In tomosynthesis mode, the compression arm assembly 110 stays in place, with the breast immobilized therein, while at least the x-ray tube assembly 112 rotates the x-ray source 126 relative to the compression arm assembly 110 (for example, plus or minus 15 degrees relative to compression arm assembly 110, plus or minus 7 degrees relative to compression arm assembly 110, or another desired angular range) and the immobilized breast about the axis 148. In some examples, the disclosed technologies may be performed in a wide-angle tomosynthesis mode, such as plus or minus 15 degrees. The imaging system 100 takes plural tomosynthesis projection images of the breast at respective angles of the x-ray beam relative to the breast.

[0069] Concurrently and optionally, the image receptor 122 may be tilted relative to the receptor housing 116 and coordinated with the rotation of the x-ray tube assembly 112. The tilting can be through the same angle as the rotation of the x-ray source 126 but may also be through a different angle selected such that the x-ray beam remains substantially in the same position on the image receptor 122 for each of the plural images. The tilting can be about the axis 148, which can, but need not, be in the image plane of the image receptor 122. The compression arm position mechanism 132 can drive the image receptor 122 in a tilting motion. For tomosynthesis imaging and / or CT imaging, the receptor housing 106 can be horizontal or can be at an angle to the horizontal, e.g., at an orientation similar to that for conventional MLO imaging in mammography. The system 100 can be solely a mammography system, a CT system, or solely a tomosynthesis system, or a “combo” system that can perform multiple forms of imaging. In some examples, other imaging modes can be contemplated.

[0070] When the system is operated, the image receptor 122 produces imaging information in response to illumination by the imaging x-ray beam from the x-ray source 126 and supplies it to an image processor of the workstation 104 (shown in FIG. 1) for processing and generating breast x-ray images. The workstation 104 may control the operation of the imaging system 100 and interacts with the health professional to receive commands and deliver information including processed x-ray images. Workstation 104 includes a display 150 (for example, a flat panel display that may include touch-screen functionality); user interface devices such as a keyboard, touch-screen, and / or a mouse / trackball; and / or various switches and indicator lights. Workstation 104 may also include computer facilities for controlling gantry 102 and for processing, storing and displaying data received from gantry 102. In some examples workstation 104 communicates with one or more other computer systems via a network. Gantry 102 and workstation 104 may exchange data and controls over a wired or wireless connection.

[0071] Images captured by system 100 are comprised by pixels, and each pixel may have an associated digital value (DV) corresponding to a delta between a high signal value and a low signal value. A pixel with a high signal value may appear black on an image and corresponds to a high amount of x-ray signal passing through the tissue / target. A pixel with a low signal value may appear white on an image and corresponds to a low amount of x-ray signal passing through the tissue / target. Areas of imaged tissue that include contrasting DVs along may indicate that a feature of the imaged tissue can be clearly identified.

[0072] For images captured by like x-ray imaging modalities (for example, images from different tomosynthesis procedures, or images from different 2D mammography procedures), the DVs of corresponding pixels in different images can be summed to generate a summed image. This summation may increase the DV contrast (for example, between dark and light areas), and the summed image may include areas where features are more clearly identifiable. Similarly, DVs of corresponding pixels in different images can be subtracted to generate a subtracted image. The summation may be initiated at any point in a chain of images. In some examples, a signal range normalization may occur before the summation occurs. Normalized projections may be summed. Additionally, slices can be summed directly, because a normalization of the input projections to the reconstruction engine may already have occurred.

[0073] FIG. 2C depicts a partial view and collimation beams 160 of the imaging system 100. When a breast is placed on compression surface 118 and immobilized (forexample, between compression surface 118 and compression paddle 114, shown in FIGS. 1-2B), a full area 154 of the entire breast may be illuminated by the x-ray beams. While it is known to collimate an x-ray emission so as to limit the amount of x-ray energy received at the detector (while imaging the entire breast), the technologies described herein contemplate collimating an x-ray beam so as to limit high-energy x-ray dose to an even smaller area, e.g., an area defined by a breast implant. When an implant (or area of dense tissue) is present in the breast, an implant area 156 is illuminated by the x-ray beams. The x-ray source 126 may include collimators 152 that limit the size of the emitted x-ray beams 160 to a desired area, for example defined by the implant or particularly dense tissue. In some examples, the image resulting from the collimated beams 160 is substantially rectangular. The collimated beams 160 may be configured (manually by a medical specialist or automatically) to illuminate an area just large enough to include the implant area 156. Automatic collimation (autocollimation) may include (a) an automatic exposure control (AEC) coupled with an AEC sensor and / or receptor to receive exposure information in a pre-imaging firing of source, (b) an autocollimation control to adjust the collimation of beams 160, (c) an auto-grid control to selectively withdraw all or a portion of a grid, and / or (d) an auto-magnification control to adjust parameters for magnification of imaging. An AEC sensor can be a conventional separate sensor that helps determine imaging exposure parameters in a pre-imaging exposure of the immobilized breast at a particular x-ray dosage. Alternatively, receptors can be used for that purpose, eliminating the need for a separate AEC sensor, because the output of receptor resulting from a low- dose pre-imaging exposure can provide the information for autoexposure control. In addition, the output of the receptor in response to the pre-imaging exposure can reveal the position of the breast relative to the receptor, and thus provide information for autocollimation to confine beams 160 to a footprint that matches the implant area 156, even when the implant area 156 is off center relative to a proximal edge of compression surface 118.

[0074] FIG. 3 depicts an example x-ray image 300 of breast tissue with a displaced implant 306, which is typical for existing procedures where the breast is imaged. In the process of creating image 300, the patient’s implant 306 was pushed close to the chest wall, to remove as much of the implant 306 from the image 300 as possible to maximize the amount of imaged breast tissue 304. Image 300 was generated using 35 kVp and 6 mAs on a breast and implant with a total thickness of 82 mm (8.2 cm), at a dose of about 0.24 mGy. Blank area 302 represents area outside of the breast where no tissue is present andall x-rays were received. Depicted in the area of the breast tissue 304 are details and features of the breast as contrasting light and dark areas on image 300. The implant 306, however, appears on image 300 as a bright white area. As can be seen, the implant 306 creates a significant artifact in the image, preventing the identification of any features that might be present in the tissue but located above or below the implant 306.

[0075] FIG. 4 depicts an example high-energy x-ray image 400 of simulated breast tissue and an implant. In image 400 (as well as FIGS. 5A, 5B, 7A, and 7B), breast tissue was simulated by the use of semicircular BR3D Breast Imaging Phantoms, Model 020 (swirls), which can be obtained from Computerized Imaging Reference Systems, Inc., 900 Asbury Ave, Norfolk, VA 23513. The swirls utilized each had an average density of 50 / 50 (meaning that each swirl slab included a 1 : 1 ratio of two materials swirled together, one material representing adipose and the other material representing gland tissue). A total of six swirls were used. Each swirl is 1 cm thick; the total thickness of all six swirls is 6 cm. Each swirl measured about 10 cm by 18 cm by 1 cm. In image 400 (as well as FIGS. 5 A and 5B), the implant was simulated by a 4.9 mm thick aluminum plate, which behaves similarly in an x-ray to both saline and silicone (the two most common implant fillers). The simulated implant was placed between the top three and bottom three breast phantoms. One of the six swirls included various features for identification. This “featured” swirl may be placed at various positions within the stack of swirls and may be place above or below the simulated implant. The features included resin spheroidal masses (for example, for simulation of breast carcinoma), fibers, and / or CaCOs specs.

[0076] Image 400 was created utilizing a high-energy x-ray technique, in which an x- ray energy of 49 kVp was used. In some examples, the energy (kVp) that is available at a gantry (such as gantry 102 including x-ray source 126) is limited by the technical capability of the source (for example, limited to 49 kVp). F or creation of image 400, an x-ray quantity of 12 mAs was utilized, and the resulting dose was 1.61 mGy. These parameters resulted in an image 400 wherein features, such as feature 408, are visible and identifiable within the region that includes the simulated implant 406. The blank area 402 surrounding the simulated tissue appears dark. The simulated tissue area 404 includes contrasting light and dark areas that correspond to tissue features. Although simulated implant area 406 appears lighter than simulated tissue area 404, the feature 408 is still clearly visible.

[0077] FIG. 5A depicts an example low-energy x-ray image 500a of simulated breast tissue with an implant. FIG. 5B depicts an example high-energy x-ray image 500b of the simulated breast tissue with implant of FIG. 5A. Simulated breast tissue, implant, andfeatures of FIGS. 5 A and 5B were the same as those outlined above regarding FIG. 4. In FIG. 5 A, Low-energy x-ray image 500a was captured using a low x-ray energy of 29 kVp, an x-ray quantity of 50 mAs, and a resulting dose of 1.41 mGy. The blank area 502a surrounding the simulated tissue appears dark. The simulated tissue area 504a includes contrasting light and dark areas that correspond to tissue features. Simulated implant area 506a appears lighter and overall brighter than simulated tissue area 504a. Simulated implant area 506a includes much less contrast than simulated tissue area 504a and appears washed-out, such that feature 508a is difficult to see and identify.

[0078] In FIG. 5B, high-energy x-ray image 500b was captured using a high x-ray energy of 49 kVp, an x-ray quantity of 10 mAs, and a resulting dose of 1.31 mGy (7% to 8% less than the resulting dose from the low-energy exposure of low-energy x-ray image 500a). The blank area 502b surrounding the simulated tissue appears dark. The simulated tissue area 504b includes contrasting light and dark areas that correspond to tissue features. Unlike feature 508a, although simulated implant area 506b appears lighter than simulated tissue area 504b, simulated implant area 506b includes more contrast between light and dark areas, and the feature 508b is clearly visible and identifiable.

[0079] FIG. 6 depicts a method 600 of imaging a breast and a breast implant in the breast simultaneously. At operation 602, a determination is made that an implant is present in the breast. For example, the determination may be made automatically by an imaging system (for example, based on previous images and / or patient data). In some examples, the determination may be made by a medical personnel.

[0080] At operation 604, a breast and a breast implant are positioned on a support platform (for example, compression surface 118) of an x-ray imaging system (for example, system 100), where an x-ray detector (for example, image receptor 122) is disposed below the support platform. The imaging method may be 2D mammography imaging, tomosynthesis imaging, general radiology, another suitable imaging modality, or a combination of imaging modalities.

[0081] At operation 606, an automatic exposure control (AEC) technique is performed (for example, manually or automatically by the imaging system) on the breast and the implant to determine a predetermined x-ray exposure dose (for example, a predetermined dose determined based at least in part based on breast size and / or density). Determining the predetermined dose includes emitting a scout high-energy x-ray (for example, a high-energy x-ray as described above) through the breast and the breast implant. The scout high-energy x-ray delivers a scout x-ray exposure to the breast. Insome examples, the high-energy x-ray has energy of at least 49 kVp. At operation 608, an imaging high-energy x-ray (for example, a high-energy x-ray as described above) is emitted through the breast and the breast implant. In some examples, the high-energy x- ray has energy of at least 49 kVp. The imaging high-energy x-ray delivers an imaging x-ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose. In examples where multiple images are to be taken, the sum of the exposures for each image may be equal to (or less than) the predetermined dose. In some examples, the high-energy x-ray is collimated to emit the high-energy x-ray primarily through the breast implant and portions of the breast tissue above and below the breast implant.

[0082] In an example, a low-energy (for example, a low-energy x-ray as described above) x-ray is emitted through the breast and the breast implant, where the low-energy x-ray delivers a x-ray exposure to the breast, and where the sum of the low-energy x-ray exposure, the scout x-ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose, but the low-energy x-ray exposure is sufficient to image the breast effectively. The low-energy x-ray is received at the x-ray detector, and the low-energy x-ray received at the x-ray is processed detector to obtain a low-energy x-ray image of the breast and the breast implant. The imaging high-energy x-ray image is summed with the low-energy x-ray image to obtain a summed image. Summing (for example, summation as described above) the high-energy x-ray image with the low-energy x-ray image may include adding a first value of a pixel in the high-energy x-ray image to a second value of the pixel in the low-energy x-ray image.

[0083] In some examples where the imaging high-energy x-ray is emitting during a first imaging modality procedure, method 600 may also include emitting, during a second imaging modality procedure different than the first imaging modality procedure, a low- energy x-ray through the breast and the breast implant. The low-energy x-ray is received at the x-ray detector. The imaging high-energy x-ray image may be displayed. The low- energy x-ray received at the x-ray detector to obtain a low-energy x-ray image of the breast and the breast implant and the low-energy x-ray image is displayed.

[0084] At operation 610, the imaging high-energy x-ray is received at the x-ray detector. At operation 612, the imaging high-energy x-ray received at the x-ray detector is processed to obtain a high-energy x-ray image of the breast and the breast implant. The high-energy x-ray image includes a breast tissue feature (for example, a breast tissue feature that can be clearly identified, such as a carcinoma / tumor or other feature) within anarea of the x-ray image defined by the breast implant. The high-energy x-ray image may be displayed (for example, on a display such as display 150) at a review device display. In some examples, method 600 also includes receiving a selection of a region of interest within an area of the high-energy x-ray image defined by the breast implant. The selected region of interest may correspond to the breast tissue feature identified within the x-ray image. A medical specialist reviewing the displayed image may select a feature / region of interest (for example, at a display of a computing system, medical equipment, or other means of image display capable of receiving user input at a user interface), and the selection of the region of interest may be received based on the user selection of the region of interest. In some examples, the region of interest may be selected automatically by the imaging system.

[0085] Method 600 may be performed on a single modality alone, or may be performed on multiple modalities, the output image formats of which may be reviewed together. In some examples, high-energy exposure images and / or low-energy exposure images may be reviewed together and may be summed (for images of like modalities). In some examples, high-energy x-rays and / or low-energy x-rays may be collimated. Collimation may be performed on an area corresponding to an area of an implant, dense area, or other feature in the breast. These different combinations and options provide a medical specialist an advantage in being able to customize the imaging to a particular patient’s needs, as well as to enable efficient and accurate diagnoses and treatment decisions. A non-exhaustive and non-limiting list of possible use cases are outlined below:

[0086] Method 600 may be performed using high-energy x-rays (for example, high- energy x-ray exposures as described above) in a 2D mammography procedure to generate x-ray images in a single mammography format.

[0087] Method 600 may be performed using high-energy x-rays (for example, high- energy x-ray exposures as described above) in a tomosynthesis procedure to generate x- ray images in a single tomosynthesis format.

[0088] Method 600 may be performed using high-energy x-rays (for example, high- energy x-ray exposures as described above) in a 2D mammography procedure, in combination with using low-energy x-rays in a tomosynthesis procedure, to generate x-ray images in multiple formats (both mammography and tomosynthesis).

[0089] Method 600 may be performed using high-energy x-rays (for example, high- energy x-ray exposures as described above) in a tomosynthesis procedure as well as usinglow-energy x-rays in a tomosynthesis procedure, to generate x-ray images in a single tomosynthesis format, and summing (for example, summation as described above) at least some of the high-energy and low-energy x-ray images.

[0090] Method 600 may be performed using high-energy x-rays (for example, high- energy x-ray exposures as described above) in a 2D mammography procedure as well as using low-energy x-rays in a 2D mammography procedure, to generate x-ray images in a single mammography format, and summing (for example, summation as described above) at least some of the high-energy and low-energy x-ray images.

[0091] Method 600 may be performed using collimated high-energy x-rays (for example, high-energy x-ray exposures as described above) in a tomosynthesis procedure as well as using low-energy x-rays in a tomosynthesis procedure, to generate x-ray images in a single tomosynthesis format, and summing (for example, summation as described above) at least some of the high-energy and low-energy x-ray images.

[0092] Method 600 may be performed using collimated high-energy x-rays (for example, high-energy x-ray exposures as described above) in a 2D mammography procedure as well as using low-energy x-rays in a 2D mammography procedure, to generate x-ray images in a single mammography format, and summing (for example, summation as described above) at least some of the high-energy and low-energy x-ray images. In some examples, the collimation may be performed on an area corresponding to an area of an implant, dense area, or other feature in the breast.

[0093] Method 600 may be performed using high-energy x-rays in a 2D mammography procedure as well as using low-energy x-rays in a 2D mammography procedure, to generate x-ray images in a single mammography format, and summing (for example, summation as described above) at least some of the high-energy and low-energy x-ray images; this may be utilized in combination with using low-energy x-rays in a tomosynthesis procedure to generate x-ray images of a tomosynthesis format.

[0094] One preconception about utilizing high-energy x-ray beams (for example, high- energy x-ray exposures as described above) in breast imaging is that the high-energy beams would result in an image having degraded tissue feature identification. The inventor of the present technology has determined that such degradation does not occur or occurs minimally, such that diagnostically relevant images may still be obtained by the technologies described herein. FIG. 7A depicts an example low-energy x-ray image 700a of simulated breast tissue. FIG. 7B depicts an example high-energy x-ray image 700b of the simulated breast tissue of FIG. 5 A. Simulated breast tissue and features of FIGS. 7Aand 7B were the same as those outlined above regarding FIG. 4. Low-energy x-ray image 700a was captured using a low x-ray energy of 29 kVp, an x-ray quantity of 48 mAs, and a resulting dose of 1.33 mGy. Blank area 702a appears dark. The simulated tissue area 704a shows areas of differing brightness that correspond to simulated tissue features. For example, feature 708a is visible and can be clearly identified.

[0095] One potential concern with utilizing high-energy x-ray images was that the high-energy x-ray energy would result in an image wherein features of the tissue in the image were less clear and less identifiable. Surprisingly, as depicted in high-energy x-ray image 700b, utilizing high-energy x-ray beams that amount to the same dose do not result in an image with degraded tissue feature identification. High-energy x-ray image 700b was captured using a high x-ray energy of 49 kVp, an x-ray quantity of only 10 mAs, and a resulting dose of 1.33 mGy (the same dose as that of low-energy x-ray image 700a). The simulated tissue area 704b still shows areas of differing brightness with adequate contrast that correspond to simulated tissue features. For example, feature 708b is just as visible as feature 708a (in FIG. 7A) and can be clearly identified.

[0096] FIG. 8 depicts an example graph of x-ray attenuation vs. energy, and associated table showing related peak voltage values. Shown are Graph 800 that depicts an example x-ray attenuation vs. energy graph, and Table 801 that depicts mean energy values relating keV and kVp values. As noted above, the ranges disclosed for historical or low-energy x-ray typically used in mammography and tomosynthesis applications are historically selected for purposes of image quality / feature contrast. These lower energies selected for reasons of attenuation of x-rays through the soft tissue of the breast, which is predominantly composed of fat, water and muscle. This is noted in Table 801 where an example historical / current maximum mammography imaging energy is listed to correspond to about 39 kVp, historically suitable for imaging fats and muscle as indicated in Graph 800. At such low energies, the contrast between bone and tissues is greater, but the detectable signals at the detector are lower when compared to the higher energies. Contrarily, for other types of historical imaging through hard tissue (such as teeth and bone imaging, for example) higher x-ray energies are used to allow imaging through the denser tissues. This is noted in Graph 800 for keV energy values greater than 70 keV, suitable for imaging bone / teeth. Typically, the higher the energy selected, the more radiation exposure a patient receives. Therefore, it would not be historically recommended to increase the energy of the x-ray for purposes of imaging as it would result in higher dose to the patient and would be thought to not result in the enhancedcontrast desired for soft tissue imaging (as discussed above regarding FIGS. 7A and 7B). However, such levels of contrast are not needed for imaging of non-breast tissue, although a satisfactory contrast level is required.

[0097] It is appreciated by the applicant that dense breast tissue, as well as breasts including implants, are not uniform in the density of the tissue. Thus, the lower energies typically / historically used in mammography and tomosynthesis applications, while allowing for the necessary contrast for soft tissue image, would not result in the image able to detect cancers obscured by dense tissue and implants. In contrast, the high energies ranges described above allow for imaging through the dense tissue and through implant while still allowing the necessary contrast to image soft tissue. In Table 801, a maximum dense tissue / implant future imaging energy is noted of about 70 kVp (noting also that many current mammography / tomosynthesis imaging systems are limited functionally to a maximum of 49 kVp). Accordingly, Graph 800 depicts an example high-energy imaging range to be from about 39 kVp to about 70 kVp (about 26 keV to about 39 keV). This range unexpectedly allows for enhanced contrast within the tissues of the breast, including dense tissues and implants, while also achieving satisfactory image quality, as shown in FIGS. 7A and 7B.

[0098] FIG. 9 depicts an example of a suitable operating environment 900 in which one or more of the present examples can be implemented. This operating environment may be incorporated directly into the controller for a breast imaging system, e.g., such as the breast imaging system 100. This is only one example of a suitable operating environment and is not intended to suggest any limitation as to the scope of use or functionality. Other well-known computing systems, environments, and / or configurations that can be suitable for use include, but are not limited to, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, programmable consumer electronics such as smart phones, network PCs, minicomputers, mainframe computers, tablets, distributed computing environments that include any of the above systems or devices, and the like.

[0099] In its most basic configuration, operating environment 900 typically includes at least one processing unit 902 and memory 904. Depending on the exact configuration and type of computing device, memory 904 (storing, among other things, instructions to perform AEC, control collimators, limit an x-ray dose for a patient, image a breast, adjust x-ray energy levels, calculate x-ray dose, or perform other methods disclosed herein) can be volatile (such as RAM), non-volatile (such as ROM,flash memory, etc.), or some combination of the two. This most basic configuration is illustrated in FIG. 9 by dashed line 906. Further, environment 900 can also include storage devices (removable, 908, and / or non-removable, 910) including, but not limited to, magnetic or optical disks or tape. Similarly, environment 900 can also have input device(s) 914 such as touch screens, keyboard, mouse, pen, voice input, etc., and / or output device(s) 916 such as a display, speakers, printer, etc. Also included in the environment can be one or more communication connections 912, such as LAN, WAN, point to point, Bluetooth, RF, etc.

[0100] Operating environment 900 typically includes at least some form of computer readable media. Computer readable media can be any available media that can be accessed by processing unit 902 or other devices having the operating environment. By way of example, and not limitation, computer readable media can include computer storage media and communication media. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of 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 technology, CD- ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, solid state storage, or any other tangible medium which can be used to store the desired information. Communication media embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term "modulated data signal" means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of the any 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.

[0101] The operating environment 900 can be a single computer operating in a networked environment using logical connections to one or more remote computers. The remote computer can be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of theelements described above as well as others not so mentioned. The logical connections can include any method supported by available communications media. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet.

[0102] In some examples, the components described herein include such modules or instructions executable by computer system 900 that can be stored on computer storage medium and other tangible mediums and transmitted in communication media. Computer storage media includes volatile and non-volatile, removable and nonremovable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules, or other data. Combinations of any of the above should also be included within the scope of readable media. In some examples, computer system 900 is part of a network that stores data in remote storage media for use by the computer system 900.

[0103] Illustrative examples of the systems and methods described herein are provided below. An embodiment of the system or method described herein may include any one or more, and any combination of, the clauses described below:

[0104] Clause 1. A method of x-ray imaging a breast and a breast implant in the breast simultaneously, the method comprising: determining that the implant is present in the breast; positioning the breast and the breast implant on a support platform of an x-ray imaging system, wherein an x-ray detector is disposed below the support platform; performing an automatic exposure control technique on the breast to determine a predetermined x-ray exposure dose, wherein determining the predetermined dose comprises: emitting a scout high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, and wherein the scout high-energy x-ray delivers a scout x-ray exposure to the breast; emitting an imaging high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein: the imaging high-energy x-ray delivers an imaging x-ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose; receiving the imaging high-energy x-ray at the x-ray detector; and processing the imaging high-energy x-ray received at the x-ray detector to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high- energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

[0105] Clause 2. The method of clause 1, further comprising receiving a selection of a region of interest within an area of the high-energy x-ray image defined by the breast implant.

[0106] Clause 3. The method of clause 2, wherein the selected region of interest corresponds to the breast tissue feature.

[0107] Clause 4. The method of clause 2, further comprising displaying the processed high-energy x-ray image.

[0108] Clause 5. The method of clause 4, wherein receiving the selection of the region of interest comprises receiving a user selection of the region of interest.

[0109] Clause 6. The method of any of clauses 1-5, wherein emitting the imaging high-energy x-ray through the breast and the breast implant comprises performing a tomosynthesis imaging procedure.

[0110] Clause 7. The method of any of clauses 1-6, wherein emitting the imaging high-energy x-ray through the breast and the breast implant comprises performing a mammography imaging procedure.

[0111] Clause 8. The method of any of clauses 1-7, further comprising: emitting a low-energy x-ray through the breast and the breast implant, wherein the low-energy x- ray delivers a low-energy x-ray exposure to the breast, wherein the sum of the low-energy x-ray exposure, the scout x-ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose; receiving the low-energy x-ray at the x-ray detector; processing the low-energy x-ray received at the x-ray detector to obtain a low-energy x- ray image of the breast and the breast implant; and summing the high-energy x-ray image with the low-energy x-ray image to obtain a summed image.

[0112] Clause 9. The method of clause 8, wherein summing the high-energy x-ray image with the low-energy x-ray image comprises adding a first value of a pixel in the high-energy x-ray image to a second value of the pixel in the low-energy x-ray image.

[0113] Clause 10. The method of any of clauses 1-9, further comprising collimating the imaging high-energy x-ray to emit the imaging high-energy x-ray primarily through the breast implant and portions of the breast above and below the breast implant.

[0114] Clause 11. The method of any of clauses 1-10, wherein the imaging high- energy x-ray is emitting during a first imaging modality procedure and wherein the method further comprises: emitting, during a second imaging modality procedure different than the first imaging modality procedure, a low-energy x-ray through the breast and the breast implant; and receiving the low-energy x-ray at the x-ray detector.

[0115] Clause 12. The method of clause 11, further comprising: displaying the high- energy x-ray image;

[0116] processing the low-energy x-ray received at the x-ray detector to obtain a low- energy x-ray image of the breast and the breast implant; and displaying the low-energy x-ray image.

[0117] Clause 13. The method of any of clauses 1-12, wherein the scout high-energy x-ray is between about 49 kVp and 74 kVp and wherein the imaging high-energy x-ray is between about 49 kVp and 74 kVp.

[0118] Clause 14. The method of clause 1, wherein the automatic exposure control technique is performed by the x-ray imaging system.

[0119] Clause 15. The method of clause 1, wherein the automatic exposure control technique is performed manually.

[0120] Clause 16. A computing system, comprising: at least one processor; and at least one memory storing computer-executable instructions for of x-ray imaging a breast and a breast implant in the breast simultaneously, the computer-executable instructions when executed by the at least one processor causing the computer to: based on the breast and the breast implant being positioned on a support platform of an x-ray imaging system, send an instruction to an x-ray source of the x-ray imaging system to emit a scout high- energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein the scout high-energy x-ray delivers a scout x-ray exposure to the breast; send a second instruction to the x-ray source of the x-ray imaging system to emit an imaging high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein: the imaging high-energy x-ray delivers an imaging x-ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose; receive the imaging high-energy x-ray at an x-ray detector, wherein the x-ray detector is disposed below the support platform; and process the imaging high-energy x-ray received at the x-ray detector to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high-energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

[0121] Clause 17. The computing system of clause 16, further comprising instructions to: transmit the high-energy x-ray image to a display of a review device.

[0122] Clause 18. The computing system of any of clauses 16-17, further comprising instructions to: based on the breast and the breast implant being positioned on the supportplatform, send a third instruction to the x-ray source to emit a low-energy x-ray through the breast and the breast implant, wherein the low-energy x-ray delivers a low-energy x- ray exposure to the breast, wherein the sum of the low-energy x-ray exposure, the scout x-ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose; and receive the low-energy x-ray at the x-ray detector, wherein processing the imaging high-energy x-ray further comprises summing the imaging high-energy x-ray received at the x-ray detector with the low-energy x-ray received at the x-ray detector to obtain the x-ray image.

[0123] Clause 19. The computing system of any of clauses 16-18, further comprising instructions to: collimate the imaging high-energy x-ray to emit the imaging high-energy x-ray primarily through the breast implant and portions of the breast above and below the breast implant.

[0124] Clause 20. The computing system of any of clauses 16-19, wherein the imaging high-energy x-ray is emitting during a first imaging modality procedure and wherein the computing system further comprises instructions to: send a third instruction to the x-ray source to emit, during a second imaging modality procedure different than the first imaging modality procedure, a low-energy x-ray through the breast and the breast implant; and receive the low-energy x-ray at the x-ray detector.

[0125] Clause 21. The computing system of clause 20, further comprising instructions to: transmit the imaging high-energy x-ray image to a display of a review device; process the low-energy x-ray received at the x-ray detector to obtain a low-energy x-ray image of the breast and the breast implant; and transmit the low-energy x-ray image to the display of the review device.

[0126] While particular uses of the technology have been illustrated and discussed above, the disclosed technology can be used with a variety of environments in accordance with many examples of the technology. The above discussion is not meant to suggest that the disclosed technology is only suitable for implementation within the environments shown and described above. As should be appreciated, the various aspects described with respect to the figures herein are not intended to limit the technology to the particular aspects described. Accordingly, additional configurations can be used to practice the technology herein and / or some aspects described can be excluded without departing from the methods and systems disclosed herein.

[0127] This disclosure described some aspects of the present technology with reference to the accompanying drawings, in which only some of the possible aspects wereshown. Other aspects can, however, be embodied in many different forms and should not be construed as limited to the aspects set forth herein. Rather, these aspects were provided so that this disclosure was thorough and complete and fully conveyed the scope of the possible aspects to those skilled in the art.

[0128] Similarly, where operations of a process are disclosed, those operations are described for purposes of illustrating the present technology and are not intended to limit the disclosure to a particular sequence of operations. For example, the operations can be performed in differing order, two or more operations can be performed concurrently, additional operations can be performed, and disclosed operations can be excluded without departing from the present disclosure. Further, each operation can be accomplished via one or more sub-operations. The disclosed processes can be repeated.

Claims

CLAIMSWhat is claimed is:

1. A method of x-ray imaging a breast and a breast implant in the breast simultaneously, the method comprising: determining that the implant is present in the breast; positioning the breast and the breast implant on a support platform of an x-ray imaging system, wherein an x-ray detector is disposed below the support platform; performing an automatic exposure control technique on the breast to determine a predetermined x-ray exposure dose, wherein determining the predetermined dose comprises: emitting a scout high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, and wherein the scout high-energy x-ray delivers a scout x-ray exposure to the breast; emitting an imaging high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein: the imaging high-energy x-ray delivers an imaging x-ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose; receiving the imaging high-energy x-ray at the x-ray detector; and processing the imaging high-energy x-ray received at the x-ray detector to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high- energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

2. The method of claim 1, further comprising receiving a selection of a region of interest within an area of the high-energy x-ray image defined by the breast implant.

3. The method of claim 2, wherein the selected region of interest corresponds to the breast tissue feature.

4. The method of claim 2, further comprising displaying the processed high- energy x-ray image.

5. The method of claim 4, wherein receiving the selection of the region of interest comprises receiving a user selection of the region of interest.

6. The method of any of claims 1-5, wherein emitting the imaging high-energy x- ray through the breast and the breast implant comprises performing a tomosynthesis imaging procedure.

7. The method of any of claims 1-6, wherein emitting the imaging high-energy x- ray through the breast and the breast implant comprises performing a mammography imaging procedure.

8. The method of any of claims 1-7, further comprising: emitting a low-energy x-ray through the breast and the breast implant, wherein the low-energy x-ray delivers a low-energy x-ray exposure to the breast, wherein the sum of the low-energy x-ray exposure, the scout x-ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose; receiving the low-energy x-ray at the x-ray detector; processing the low-energy x-ray received at the x-ray detector to obtain a low- energy x-ray image of the breast and the breast implant; and summing the high-energy x-ray image with the low-energy x-ray image to obtain a summed image.

9. The method of claim 8, wherein summing the high-energy x-ray image with the low-energy x-ray image comprises adding a first value of a pixel in the high-energy x- ray image to a second value of the pixel in the low-energy x-ray image.

10. The method of any of claims 1-9, further comprising collimating the imaging high-energy x-ray to emit the imaging high-energy x-ray primarily through the breast implant and portions of the breast above and below the breast implant.

11. The method of any of claims 1-10, wherein the imaging high-energy x-ray is emitting during a first imaging modality procedure and wherein the method further comprises:emitting, during a second imaging modality procedure different than the first imaging modality procedure, a low-energy x-ray through the breast and the breast implant; and receiving the low-energy x-ray at the x-ray detector.

12. The method of claim 11, further comprising: displaying the high-energy x-ray image; processing the low-energy x-ray received at the x-ray detector to obtain a low- energy x-ray image of the breast and the breast implant; and displaying the low-energy x-ray image.

13. The method of any of claims 1-12, wherein the scout high-energy x-ray is between about 49 kVp and 74 kVp and wherein the imaging high-energy x-ray is between about 49 kVp and 74 kVp.

14. The method of claim 1, wherein the automatic exposure control technique is performed by the x-ray imaging system.

15. The method of claim 1, wherein the automatic exposure control technique is performed manually.

16. A computing system, comprising: at least one processor; and at least one memory storing computer-executable instructions for of x-ray imaging a breast and a breast implant in the breast simultaneously, the computerexecutable instructions when executed by the at least one processor causing the computer to: based on the breast and the breast implant being positioned on a support platform of an x-ray imaging system, send an instruction to an x-ray source of the x-ray imaging system to emit a scout high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein the scout high-energy x-ray delivers a scout x-ray exposure to the breast;send a second instruction to the x-ray source of the x-ray imaging system to emit an imaging high-energy x-ray having an x-ray energy of at least 49 kVp through the breast and the breast implant, wherein: the imaging high-energy x-ray delivers an imaging x-ray exposure to the breast, and the sum of the scout exposure and the imaging x-ray exposure does not exceed the predetermined x-ray exposure dose; receive the imaging high-energy x-ray at an x-ray detector, wherein the x-ray detector is disposed below the support platform; and process the imaging high-energy x-ray received at the x-ray detector to obtain a high-energy x-ray image of the breast and the breast implant, wherein the high-energy x-ray image comprises a breast tissue feature within an area of the x-ray image defined by the breast implant.

17. The computing system of claim 16, further comprising instructions to: transmit the high-energy x-ray image to a display of a review device.

18. The computing system of any of claims 16-17, further comprising instructions to: based on the breast and the breast implant being positioned on the support platform, send a third instruction to the x-ray source to emit a low-energy x-ray through the breast and the breast implant, wherein the low-energy x-ray delivers a low-energy x-ray exposure to the breast, wherein the sum of the low-energy x-ray exposure, the scout x-ray exposure, and the imaging x-ray exposure does not exceed the predetermined dose; and receive the low-energy x-ray at the x-ray detector, wherein processing the imaging high-energy x-ray further comprises summing the imaging high-energy x-ray received at the x-ray detector with the low-energy x-ray received at the x-ray detector to obtain the x-ray image.

19. The computing system of any of claims 16-18, further comprising instructions to:collimate the imaging high-energy x-ray to emit the imaging high-energy x-ray primarily through the breast implant and portions of the breast above and below the breast implant.

20. The computing system of any of claims 16-19, wherein the imaging high-energy x-ray is emitting during a first imaging modality procedure and wherein the computing system further comprises instructions to: send a third instruction to the x-ray source to emit, during a second imaging modality procedure different than the first imaging modality procedure, a low-energy x- ray through the breast and the breast implant; and receive the low-energy x-ray at the x-ray detector.

21. The computing system of claim 20, further comprising instructions to: transmit the imaging high-energy x-ray image to a display of a review device; process the low-energy x-ray received at the x-ray detector to obtain a low- energy x-ray image of the breast and the breast implant; and transmit the low-energy x-ray image to the display of the review device.

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