Patent Application
20250090116
Existing mammography systems image breast tissue in a transmission mode by measuring the attenuation of an X-ray source transmitted directly through the breast relative to the initial intensity of the X-ray source in one or more energy ranges. Mammograms from existing digital systems are either projections of a single view of the breast tissue from the X-ray source directly onto a 2D X-ray detector pixel array or, in a 3D mammography system, a 3D tomographic X-ray transmission image is computed from several projection views. In existing mammography systems without energy discrimination, projection images consist of grayscale values that are effectively controlled by tissue density. Tissue density can be similar enough between cancerous and benign tissue that it is difficult or impossible to differentiate with density alone. In systems with some energy discrimination, which can be achieved either through multi-energy channel detectors or multiple measurements with different source operating parameters or filtration, images composed of more than a single value per pixel can be computed, providing some additional contrast to features in the mammogram. Mammograms from these existing systems are inspected by a clinician for regions that they deem could potentially be malignant tissue. Whether they are true grayscale or multi-energy enhanced transmission-based images, mammograms from existing mammography systems provide limited information upon which the clinician must make a decision as to whether a region of tissue is cancerous, such that 70-80% of mammograms that are flagged for biopsy in the U.S. ultimately prove to be benign upon inspection of the biopsied tissue by a pathologist.
Approximately 30% of new female cancers are breast cancer, and there is an average risk of about 13% that a woman will develop breast cancer during their lifetime. According to the American Cancer Society, when breast cancer is detected early and in a localized stage then a woman has a 99% 5-year relative survival rate. Therefore, there is a need for a mammogram system that accurately detects breast cancer.
The present invention is generally directed to medical imaging, more specifically, the present invention is directed to mammography and X-ray scatter tomography for creating spatially resolved volumetric X-ray scatter spectral reconstructions.
To date, the discriminatory power of X-ray scatter measurements for breast tissue has only been demonstrated ex vivo in relatively controlled sample and measurement scenarios, but the recent development of X-ray scattering methodologies that employ coded apertures allow for spatially resolved volumetric X-ray scatter spectral reconstructions to be implemented in a sample and measurement scenario similar to those of a typical mammography system. An in vivo coded aperture-based X-ray scatter imaging system and methodology offers additional spatially resolved estimates of the likelihood a region of tissue is cancerous to a clinician, based on information that would never be accessible in a transmission-only mammography system.
The subject matter described herein includes a system and method for coded aperture-based X-ray scatter tomography of breast tissue in vivo. With this system and method, spatially resolved volumetric X-ray scatter spectral reconstructions of breast tissue in vivo are used to provide spatially resolved estimates of tissue type. Specifically, these estimates may include the likelihood that regions of breast tissue are cancerous based on comparisons to reference X-ray spectra of benign and cancerous tissue types. Given that 70-80% of mammograms flagged for biopsy prove negative, such estimates provide valuable additional information to aid clinicians in making biopsy decisions. No known prior art provides spatially resolved volumetric X-ray scatter spectral reconstructions or derived tissue type likelihood estimates calculated from X-ray scatter spectral data for breast tissue in vivo.
In contrast to X-ray transmission measurements of tissue, which can only provide the same number of features per pixel as number of effective energy channels in the measurement, spatially resolved volumetric X-ray scatter spectral reconstructions provide as many features as allowed by the energy resolution, the geometry of the measurement (particularly the size and pixel pitch of the detector when acquiring in a mostly angle-dispersive mode), and the accuracy of the model used for reconstruction. These additional features are also largely orthogonal from those provided by X-ray transmission measurements, i.e., they provide distinct information from any transmission X-ray measurement modality. More importantly for informing a clinician, transmission X-ray measurements are inherently limited by the similar and potentially overlapping density values of malignant and benign tissue, while X-ray scatter measurements of tissue have been shown to distinguish between cancerous and benign tissue ex vivo.
The mammography system described herein comprises a movable X-ray source for generating a primary X-ray beam for irradiating a breast of a patient. The X-ray source is adjustable based on at least one operating parameter that includes exposure time, current, voltage, or filtration. The mammography system further comprises a collimator between the X-ray source and the breast of the patient to shape the primary X-ray beam. The collimator includes an opening that is configurable in at least one dimension. The mammography system further includes a plurality of movable breast plates to position the breast of the patient in a path of the primary X-ray beam. The mammography system further comprises an X-ray detector array comprising a plurality of movable X-ray detecting elements. The X-ray detector array is configurable to position at least one X-ray detecting element distally from the X-ray source at a first measurement location in the path of the primary X-ray beam to measure transmitted X-ray radiation from the primary X-ray beam. The X-ray detector array is further configurable to position at least one X-ray detecting element distally from the X-ray source at a second measurement location outside the path of the primary X-ray beam past the breast of the patient to measure scattered X-ray radiation from the primary X-ray beam. The mammography system further comprises a coded aperture positioned distally from the X-ray source between the breast of the patient and the X-ray detector array, wherein the coded aperture is configured to modulate scattered X-ray radiation from the breast of the patient detected by the X-ray detector array. The mammography system is configurable to perform an X-ray scatter measurement and an X-ray transmission measurement. When performing the X-ray scatter measurement, the X-ray detector array is configured such that at least one X-ray detecting element of the plurality of X-ray detecting elements is positioned out of the path of the primary X-ray beam to detect scattered X-ray radiation from the primary X-ray beam passing through the breast of the patient. When performing the X-ray transmission measurement, the X-ray detector array is configured such that at least one X-ray detecting element of the plurality of X-ray detecting elements is positioned to detect X-rays transmitted through the breast of the patient from the primary X-ray beam. The mammography system further comprises a control system comprising memory and a processor. The processor is configured for configuring the mammography system for an X-ray transmission measurement or an X-ray scatter measurement. Configuring the mammography system includes controlling at least one configuration parameter. The at least one configuration parameter includes a position of the X-ray source, a position of the X-ray detector array, a dimension of the opening of the collimator, at least one operating parameter of the X-ray source, and a position of the plurality of breast plates. The processor is further configured for receiving X-ray transmission data detected by the X-ray detector array. The processor is further configured for producing an X-ray radiodensity mammogram image based on the received X-ray transmission data. The processor is further configured for identifying a region of interest in the breast of the patient based on the X-ray radiodensity mammogram image. The processor is further configured for determining at least one scatter configuration parameter for the X-ray scatter measurement based on the identified region of interest in the breast of the patient. The processor is further configured for configuring the mammography system for the X-ray scatter measurement based on the at least one determined scatter configuration parameter. The processor is further configured for receiving X-ray scatter data detected by the X-ray detector array. The processor is further configured for estimating a spatially resolved X-ray scatter spectral reconstruction based on the received X-ray scatter data, the received X-ray transmission data, and the at least one scatter configuration parameter. The processor is further configured for determining a spatially resolved tissue property based on the received X-ray scatter data of the region of interest. The processor is further configured for producing a spatially resolved scatter mammogram image based on the received X-ray transmission data and the received X-ray scatter data. There are many potential embodiments of the mammography system, several of which are described further below.
The method of performing spatially resolved volumetric X-ray scatter tomography mammography described herein comprises performing an X-ray transmission measurement. The X-ray transmission measurement comprises transmitting a first primary X-ray beam from an X-ray source through a collimator having an opening configurable in at least one dimension to shape the first primary X-ray beam and through a breast of a patient positioned between a plurality of breast plates. The X-ray source is adjustable based on at least one operating parameter that includes exposure time, current, voltage, or filtration. The X-ray transmission measurement further comprises detecting X-ray radiation from the first primary X-ray beam transmitted directly through the breast of the patient using at least one X-ray detecting element of an X-ray detector array. The X-ray transmission measurement further comprises receiving X-ray transmission data via a control system including a processor and memory from the X-ray detector array. The method further comprises producing a radiodensity mammogram image of the breast of the patient based on the received X-ray transmission data. The method further comprises identifying a region of interest in the breast of the patient based on the radiodensity mammogram image. The method further comprises determining at least one scatter measurement configuration parameter for an X-ray scatter measurement of the identified region of interest in the breast of the patient. The scatter measurement configuration parameter includes a position of the X-ray source, a position of the plurality of the X-ray detecting elements, a dimension of the opening of the collimator, an X-ray source operating parameter, and a position of the plurality of breast plates. The method further comprises performing the X-ray scatter measurement of the region of interest. The X-ray scatter measurement comprises transmitting a second primary X-ray beam from the X-ray source through the collimator to shape the second primary X-ray beam and through the breast of the patient positioned with the plurality of breast plates. The X-ray scatter measurement further comprises modulating scattered X-ray radiation from the second primary X-ray beam interacting with the breast of the patient using a coded aperture positioned between the breast of the patient and the plurality of X-ray detecting elements. The X-ray scatter measurement further comprises detecting the modulated scattered X-ray radiation using the X-ray detector array. The X-ray scatter measurement further comprises receiving X-ray scatter data representing detected scattered X-ray radiation from the X-ray detector array. The method further comprises calculating a spatially resolved X-ray scatter spectral reconstruction based on the received X-ray scatter data, the received X-ray transmission data, and the determined scatter measurement configuration parameter. The method further comprises determining at least one spatially resolved tissue property based on the received X-ray scatter data of the region of interest. The method further comprises producing a spatially resolved scatter mammogram image based on the received X-ray transmission data and the received X-ray scatter data. There are many potential embodiments of the method, several of which are described further below.
Scattered X-ray radiation from breast tissue contains tissue-specific information. More specifically, tissue X-ray diffraction (XRD) spectra reflect local molecular ordering. For example, fat, gland, and cancerous tissue have different molecular ordering which results in distinct XRD spectra.
There are many potential embodiments of the system, several of which are described further below. The system includes at least one X-ray source to irradiate breast tissue. The system also includes at least one collimation stage between the X-ray source and the breast tissue. The system further includes a coded aperture positioned between the breast tissue and the detector. The system further includes a processor which can use the detected X-ray scatter signal, which has been modulated by the coded aperture, to compute a spatially resolved estimate of the tissue types of the irradiated breast tissue. Lastly, the system may further include a component for representing the tissue type estimate data to the operator or clinician, e.g., a computer monitor.
Molecular ordering also impacts density. In existing transmission mammography systems, the local molecular ordering is generally collapsed down to a single radiodensity value. However, the mammography system described herein is designed to generate spatially resolved X-ray scatter spectra of the region of breast tissue on which the scatter measurement and reconstruction are performed. The X-ray scatter spectra provides more features and to increase the contrast for differentiation of tissue types relative to existing mammography systems and the spatially resolved nature of the reconstructed data allows this differential ability to be associated with specific, known locations in the breast of the patient, and therefore correlated with observable features in radiodensity mammogram images produced by transmission measurements. The irradiance and X-ray energy spectrum reaching the breast tissue can be controlled using filters, which can be done to minimize the dose the patient receives as well as to improve contrast and X-ray spectral resolution. The cross-sectional shape (e.g., pencil, fan, or cone beam), divergence, and spatial extent of the X-ray beam reaching the breast tissue can be controlled with collimators between the X-ray source and the breast tissue. Second, the scattered X-rays are measured with an X-ray detector. A coded aperture, i.e., a patterned aperture with a known open fraction and pattern, is located between the breast tissue and the X-ray detector to selectively and purposefully attenuate the scattered X-rays based on the known code pattern and measurement geometry. Third, a spatially resolved estimate of the tissue types of the irradiated breast tissue is computed from the detected coded aperture modulated X-ray scatter signal using the processor. Finally, the estimates of the tissue types are presented to the operator or clinician using the display component. For example, and not limitation, the mammography system described herein is designed to generate a color map, overlaid onto an X-ray transmission image, corresponding to estimated tissue types and/or a likelihood of cancer. Additionally, the mammography system may flag a region of the transmission image that includes a value for the percentage of the likelihood of cancer. Advantageously, the mammography system is further operable to measure and display the X-ray scatter data of a subregion of the transmission data (e.g., scatter spot-checking during transmission magnification mode).
Spatially resolved volumetric X-ray spectral data can be reconstructed from an irradiated volume using a coded aperture to modulate the scatter, a 2D pixelated detector to measure the modulated scatter signal, a forward matrix model of the physics and the geometry of the measurement, and a processor to iteratively estimate, by commonly known algorithms (e.g., maximum likelihood estimation), the spatially resolved volumetric X-ray spectral data from the forward matrix model. This general procedure is used in the methods described herein. Specifically, this includes estimation of momentum transfer spectra on a pixel or voxel basis, which can be compared to reference momentum transfer spectra, such as those of cancerous tissue or benign adipose or gland tissue, or utilized in machine learning classification methods.
The specific embodiments discussed below include direct transmission measurements and are generally descriptive of embodiments of the system that have similar geometries, components, and form factors to existing mammography systems.
The embodiments illustrated, described, and discussed herein are illustrative of the present invention. As these embodiments of the present invention are described with reference to illustrations, various modifications or adaptations of the methods and or specific structures described may become apparent to those skilled in the art. It will be appreciated that modifications and variations are covered by the above teachings and within the scope of the appended claims without departing from the spirit and intended scope thereof. All such modifications, adaptations, or variations that rely upon the teachings of the present invention, and through which these teachings have advanced the art, are considered to be within the spirit and scope of the present invention. Hence, these descriptions and drawings should not be considered in a limiting sense, as it is understood that the present invention is in no way limited to only the embodiments illustrated.
For the purposes of promoting an understanding of the present disclosure, reference will be made to preferred embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alteration and further modifications of the disclosure as illustrated herein, being contemplated as would normally occur to one skilled in the art to which the disclosure relates.
Articles “a” and “an” are used herein to refer to one or to more than one (i.e., at least one) of the grammatical object of the article. By way of example, “a composite” means at least one composite and can include more than one composite.
Throughout the specification, the terms “about” and/or “approximately” may be used in conjunction with numerical values and/or ranges. The term “about” is understood to mean those values near to a recited value. For example, “about 40 [units]” may mean within +/−25% of 40 (e.g., from 30 to 50), within +/−20%, +/−15%, +/−10%, +/−9%, +/−8%, +/−7%, +/−6%, +/−5%, +/−4%, +/−3%, +/−2%, +/−1%, less than +/−1%, or any other value or range of values therein or there below. Furthermore, the phrases “less than about [a value]” or “greater than about [a value]” should be understood in view of the definition of the term “about” provided herein. The terms “about” and “approximately” may be used interchangeably.
As used herein, the verb “comprise” as is used in this description and in the claims and its conjugations are used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded.
Throughout the specification the word “comprising,” or variations such as “comprises” or “comprising,” will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers, or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. The present disclosure may suitably “comprise,” “consist of,” or “consist essentially of,” the steps, elements, and/or reagents described in the claims.
It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only,” and the like in connection with the recitation of claim elements, or the use of a “negative” limitation.
In the descriptions herein, the measured scatter signal and reconstructed spatially resolved scatter spectra are referred to as pertaining to the “X-ray scatter,” though the X-ray scatter field will in general be comprised of both Rayleigh and Compton scatter. The use of the measured scatter signal and reconstructed spatially resolved scatter spectra and similar terminology, particularly the use of the term “diffraction,” is not intended to limit the present invention to pertaining to scatter arising from one physical process and not another.
Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Preferred methods, devices, and materials are described, although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure. All references cited herein are incorporated by reference in their entirety.
The subject matter described herein is generally directed to mammography, and more specifically to mammography systems that use coded apertures to modulate the scattered X-ray radiation from the irradiated breast of a patient. More specifically, the subject matter described herein is directed to mammography systems that measure the modulated scattered X-ray radiation from the breast for estimating a spatially resolved volumetric X-ray scatter tomography spectral reconstruction of the breast. Spatially resolved volumetric X-ray scatter tomography is defined herein as the measurement of X-ray scatter spectra throughout a tomographic image, such that each pixel or voxel contains an additional dimension of data which is the spatially resolved scatter measurement. This tomographic image is obtained by conducting X-ray scatter measurements. The X-ray scatter measurements include detecting X-rays scattering from tissues and processing the X-ray scatter measurement data to localize scattered X-rays angle and origin from within the tissue. Such mammography systems are designed to measure spatially resolved structural differences in a patient's body at a cellular level as reflected in the spatially resolved volumetric X-ray scatter spectral reconstruction.
Existing X-ray mammography systems comprise X-ray sources to produce X-rays and an X-ray detector to capture the X-rays after passing through the patient's tissue. In this manner, existing X-ray mammography systems operate in a transmission mode and perform X-ray transmission measurements which are used to generate transmission, or X-ray radiodensity, mammogram images. The X-ray radiodensity intensity scale is based on the amount of X-rays transmitted through the tissue. The measurement of the X-rays transmitted through the tissue represents the X-ray transmission measurement. X-ray radiodensity mammogram images can be two dimensional or three dimensional, with three dimensional mammogram images being tomographically reconstructed from X-ray transmission measurements from multiple perspectives of the tissue. Clinicians evaluate X-ray radiodensity mammograms based on the shape and radiodensity of features observed in the tissue. Adipose tissue is less dense than other types of breast tissue, whereas cancerous tissue can have similar density to healthy gland tissue or benign masses. Calcifications in the tissue are more dense than adipose, glandular, and cancerous tissues, as well as fibroadenoma, but are not a definitive indication of the presence of cancerous tissue. Therefore, in general, cancerous tissue cannot be unambiguously distinguished from healthy tissue in X-ray radiodensity mammograms.
Beam divergence results in X-ray beams becoming larger in area and less intense the further the distance from the X-ray source. This further causes some magnification of an object being radiographed. The basic principle of transmission X-ray imaging is that X-rays travel in straight lines. However, when X-ray scattering events occur in the patient, the resulting scattered X-rays are not aligned with the trajectory of the original primary X-ray beam. In existing transmission mammography systems, scattered radiation detected by the X-ray detector can be a significant cause of image degradation. Scattered radiation generates undesired image intensity that is not indicative of the radiodensity of the tissue along the straight line path from the source in the region of the image in which it is detected, which can significantly reduce contrast. Contrast can be increased in digital radiodensity images by windowing, leveling, or other adjustment schemes, so for digital radiographic images, scatter acts chiefly as a source of noise, degrading the signal-to-noise ratio (SNR).
Therefore, in transmission mammography, it is typically important to control the amount of scatter radiation reaching the X-ray detector to create a high-quality image. Scatter radiation causes unwanted exposure to an image. To address the undesired image intensity generated in transmission mammograms by scattered radiation, anti-scatter grids are used to absorb scatter radiation exiting a patient and reduce the amount of scatter reaching the image detector. An anti-scatter grid is a component placed near a detector that is designed to angularly reject X-rays not originating from the X-ray source. The anti-scatter grid blocks many of the scattered X-rays that, in a transmission measurement, are a source of noise or image degradation. In contrast, for volumetric X-ray diffraction imaging, these scattered X-rays are the desired source of signal that need to be measured. For these measurements, the anti-scatter grid is removed from the system. The coded aperture component is positioned between the breast and detector, but not directly against the detector like the anti-scatter grid. The coded aperture absorbs some of the scattered X-rays while letting others pass through to the detector. The absorption of some of the scattered X-rays generates unique shadows within the measured scatter data that an algorithm (e.g., maximum likelihood estimation) benefits from, enabling the computation of scattered X-ray origins and scattered angles that generate the X-ray scatter spectra of the volumetric X-ray diffraction image.
In addition to beam-modifying and/or restricting devices, two major factors affect the amount and energy of scatter radiation exiting the patient's tissue: kilovoltage peak (kVp) and the volume of tissue irradiated. The volume of tissue depends on the thickness of a region of interest, the sub-region within a patient that an operator is interested in examining, and the X-ray beam field size. Increasing the volume of tissue irradiated results in increased scatter production. In addition, using a higher kVp increases X-ray transmission and reduces its overall absorption (photoelectric interactions); however, higher kVp increases the percentage of photon interactions (e.g., Compton interactions, Thomson scattering) and the energy of scatter radiation exiting the patient. Using higher kVp or increasing the volume of tissue irradiated results in increased scatter radiation reaching the image detector.
While performing mammography, one goal is to limit the beam field size to an area of interest. In order to limit the field size, the X-ray beam is restricted to limit patient exposure and reduce the amount of scatter radiation produced. For example, an unrestricted beam projects beyond the boundaries of the image detector and increases patient exposure. Increasing the collimation decreases the volume of tissue irradiated, the amount of scatter radiation produced, the number of photons that strike the patient, and the number of X-ray photons reaching the image detector to produce the latent image. Therefore, in order to improve a radiodensity mammography image by limiting scatter radiation, a mammography system should include controllable beam-modifying and/or restricting devices and/or components. For X-ray scatter measurements with the present invention, controlling the region of interest of irradiated tissue via collimation allows for measuring less scatter from non-suspicious regions of tissue so, while the total strength of the full scattered radiation field is decreased, there is less multiplexing of scatter from non-suspicious regions of tissue in the total measured scatter signal, allowing for measuring more useful scatter signal with less total radiation dose to the patient.
To address the aforementioned problems, in one embodiment, the mammography system described herein includes an X-ray source (x-ray generator), an X-ray tube, a collimator, at least one compression plate, anti-scatter grid, a coded aperture, and an image detector. The X-ray source is designed for delivering, modulating, and regulating electrical energy required by the X-ray tube. The X-ray tube is designed to emit, accelerate, and decelerate electrons to produce X-radiation. The voltage applied between the electrodes (cathode and anode) accelerates the electrons. The anode material determines the characteristics of the radiation. The X-ray source and X-ray tube affect the radiation yield, exposure time, and image quality. The collimator controls the shape of the X-ray beam and subsequent illuminated tissue volume. The compression plate is manually and/or automatically adjustable to alter the thickness and pressure on a region of interest of a patient. Advantageously, for transmission measurements, adequate compression results in less scattering of radiation, improved contrast due to less beam hardening, reduced radiation dose, prevents motion blurring, better image geometry, and better tissue separation.
In one embodiment, the mammography system includes an auxiliary filter placed in the X-ray beam path to modify the photon spectrum of the primary X-ray beam and to optimize radiation quality. For example, and not limitation, the filter material includes, but is not limited to, molybdenum, rhodium, copper, and aluminum. In another embodiment, the collimator is designed to decrease a patient dose, scatter radiation, and exposure to image receptor while increasing radiographic contrast.
A general depiction of such an embodiment of the mammography system is shown in
Mammography system 100 separately performs X-ray transmission measurements and X-ray scatter measurements and uses different configurations for the X-ray transmission measurements versus the X-ray scatter measurements. More specifically, mammography system 100 performs an initial X-ray transmission measurement or set of X-ray transmission measurements with accompanying data processing to produce two-dimensional (2D) or three-dimensional (3D) transmission mammograms that are typical of existing digital mammography methods, followed by a subsequent X-ray scatter measurement or set of X-ray scatter measurements and associated data processing to calculate spatially resolved X-ray scatter spectral reconstructions and the associated estimates of tissue type for the illuminated tissue volume in the X-ray scatter measurement, as explained in more detail below. Spatially resolved X-ray scatter spectral reconstructions are defined here as the multi-dimensional data or image that contains X-ray scatter spectra within each spatial location, as reconstructed (or computed) by a reconstruction algorithm (e.g., maximum likelihood estimation). Advantageously, mammography system 100 identifies a region of interest of the transmission mammogram to perform X-ray scatter measurements and tissue type analysis, which minimizes a radiation dose to the patient, improves speed of the total measurement and analysis process, and facilitates adoption of the methods by clinicians, relative to a method that performs scatter measurements of the entire breast. Alternatively, or additionally, mammography system 100 may receive a selection of the region of interest via a user interface. Transmission mammogram data can also be used jointly with reconstructed estimates of pixel or voxel scatter spectra to classify tissue.
The mammography system described herein is designed for scattered X-rays to pass through the coded aperture such that the intensity of the scattered X-rays is modulated based on the aperture pattern. This results in different magnifications and projections of shadows in the scatter data. In addition to the spatially dependent intensity modulations, different tissue types have different scatter signatures. The mammography system may simultaneously measure all irradiated tissue points. The raw modulated scatter data is summed from all irradiated tissue points. The measured scatter data may be processed (e.g., background subtraction or Fourier filtration). The mammography system reconstructs X-ray scatter spectra of the object space, where there are the number of chosen object dimensions plus an additional dimension for the scatter data. This can include a reconstruction with three spatial dimensions and a fourth scatter dimension. In such an example, the reconstruction would consist of 4D pixels, referred to in some contexts as toxels. As an example, and not limitation, using a system of linear equations, the mammography system reconstructs the X-ray spectral data of the object space by vectorizing the entire pixelated intensity of scatter data, then vectorizing the entire reconstructed spatially resolved object space spectral map. Next, the mammography system creates a forward matrix that represents the forward projection of the scatter X-rays from an object vector to a measurement vector. As an example, the detected scatter intensity vector equals the forward matrix multiplied by the XRD map vector. The forward matrix may include a spatial model of the coded aperture with attenuation properties and locations relative to each point in object space and each point in the detector space. The mammography system may further include at least one algorithm to estimate the object space using the measured detector space and a model of the XRD map system. The coded aperture enables differentiation in the X-ray signal based on location in the breast tissue to accurately estimate XRD spectra in each voxel and generate a toxel map.
For example, and not limitation, in one embodiment, the X-ray source is configured to generate a pencil beam to perform an X-ray scatter measurement and acquire data for a region of interest flagged by a user and/or the software of the mammography system. The mammography system determines that the X-ray source may be moved to change the perspective of the breast, provide a shorter beam through the tissue, vary types of tissue the beam passes through (e.g., to minimize the amount of gland tissue in the beam path), and generally to target the region of interest. Decreasing the amount of tissue that the X-ray beam passes through will result in less attenuation of the scatter X-ray signal and therefore a lower amount of radiation dosage needed for the same signal to noise quality of the measured scatter data. Additionally, the collimator is adjustable to move the pencil beam from the X-ray source through the region of interest to minimize the beam path. The mammography system may move the beam block so the direct X-ray beam is blocked from reaching the detector. The detector and/or coded aperture may be moved to optimize the X-ray scatter measurements (e.g., capture more signal or a more relevant region of the scatter radiation field in a shorter amount of time). The mammography system may further adjust X-ray exposure time, an amount of current, and/or voltage to optimize dosage and the measurement signal-to-noise ratio.
Some specific features of the components in these similar embodiments of the system are shown in
An embodiment of the mammography system that facilitates demonstration of the first transmission measurement and second scatter measurement of a region of interest, or switching between a transmission measurement and a scatter measurement is shown in
A similar embodiment of the mammography system to that shown in
Another similar embodiment includes separate detectors for transmission and diffraction measurements and is shown in
The embodiments of the mammography system that are described in the preceding paragraphs and shown in
Another embodiment of the mammography system is shown in
Another embodiment of the mammography system that allows for varying perspective on the breast tissue for the X-ray scatter measurement(s) is shown in
Another approach for using the X-ray scatter reconstruction to add clinically relevant visual contrast to a standard X-ray radiodensity mammogram generated from X-ray transmission measurements is shown in
The mammography system described herein further includes controllable electronics. In one embodiment, the mammography device includes components such as a processor, a system memory having a random-access memory (RAM) and a read-only memory (ROM), an I2C sensor, a system bus that couples the memory to the processor. The processor manages the overall operations of the mammography system. The processor is any controller, microcontroller, or microprocessor that is capable of processing program instructions. In one embodiment, the control electronics includes at least one antenna, which enables the mammography system to send information to at least one remote device and/or receive information from at least one remote device. The at least one antenna provides wireless communications, standards-based or non-standards-based including but not limited to, radiofrequency (RF), Wi-Fi, Bluetooth, Zigbee, near field communication (NFC), 3G, 4G, and/or 5G Cellular or other similar communication methods.
As further example, the processor may be a general-purpose microprocessor (e.g., a central processing (CPU)), a graphics processing unit (GPU), a microcontroller, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Programmable Logic Device (PLD), a controller, a state machine, agate or transistor logic, discrete hardware components or any other suitable entity or combinations thereof that can perform calculations, process instructions for execution, and/or other manipulations of information.
The mammography system described herein is operable to analyze image data to determine whether to modify an X-ray beam and the positioning of the components of the mammography device. For example, and not limitation the at least one processor is designed to control the cross-sectional shape, divergence, and spatial extent of the initial X-ray beam(s) and one or more filters to modify the energy spectrum and irradiance of the X-ray beam(s) reaching the breast tissue, located between the X-ray source(s) and the breast tissue. Advantageously, if the at least one processor detects that the image data has poor quality, the at least one processor is operable to transmit a command to the x-ray source to change at least one of the shape, divergence, spatial extent, and/or intensity based on the quality.
Yet another advantage of the mammography system described herein is the ability to classify tissue based on image data (e.g., scatter data). Using a modulated coded aperture, the mammography system described herein is operable to receive image data corresponding to the breast of a patient and classify the breast tissue.
The mammography system described herein is further operable to analyze X-ray transmission data and determine a tissue type (e.g., adipose, normal, fibroglandular, cancer), optimize power supplied, system efficiency, a signal to noise ratio, an angle of scatter, momentum transfer. Advantageously, the mammography system described herein is operable to identify a healthy tissue margin based on the transmission image data and generate at least one recommendation based on the transmission image data. For example, and not limitation, the at least one recommendation includes identifying a region of interest to be removed. Another example includes a recommendation to modify and/or swap the coded aperture if the signal to noise ratio and/or received transmission data is insufficient.
In one embodiment, the mammography system described herein includes at least one algorithm designed to analyze the received image data to determine at least one tissue property (e.g., tissue classification). For example, and not limitation, the at least one algorithm includes a deblurring algorithm. In yet another embodiment, the at least one algorithm includes a machine learning algorithm. For example, and not limitation, the machine learning algorithm includes a supervised learning algorithm (e.g., classification), a semi-supervised learning algorithm, an unsupervised learning algorithm, and/or a reinforcement learning algorithm. In yet another example, the machine learning algorithm includes a Naïve Bayes algorithm, a K Means clustering algorithm, a Support Vector Machine (SVM) algorithm, a linear regression algorithm, a logistic regression algorithm, an artificial neural network, a decision trees, a random forest, a K-nearest-neighbor algorithm, a gradient boosting algorithm, and/or a dimensionality reduction algorithm.
There are several commonalities of the embodiments of the mammography system and method described above that provide key advantages when implemented. One such commonality is components that are used in both X-ray transmission measurements and X-ray scatter measurements. This allows for lower total system cost, less likelihood of component failure, and potential for decreased overall measurement time. Another commonality is the ability for key components (e.g., X-ray sources, collimators, coded apertures, and X-ray detectors) to rotate or translate. This allows for: certain combinations of the components to be used in one measurement mode (e.g., for X-ray scatter measurements or X-ray transmission measurements) and not the other, or both measurement modes, potentially saving on component costs; directing the X-ray source and accompanying X-ray scatter measurement components (e.g. pencil or fan beam collimators, coded apertures, beam blocks, detectors) in order to measure a specified sub-region of tissue, which could be used to lower patient dose or optimize measurements for reconstruction performance; measurements from multiple perspectives in either X-ray transmission or X-ray scatter modes, which could also be used to optimize performance; implementation of an embodiment of the system described herein that is readily integrated into an existing transmission-based mammography system.
Further specific aspects of potential embodiments of the general method may provide further advantages. One such specification is that the transmission and scatter measurements are performed synchronously over the same time period, which would reduce measurement time and could potentially reduce dose to the patient if the same beam was used synchronously for scatter and transmission measurements. The key components of the general system may vary in ways that would be common knowledge to those trained in the art and have obvious associated advantages in their implementation. These variations include but are not limited to variations in the type of X-ray source (e.g. X-ray generator versus radioactive isotope, generator anode material, generator focal spot size), variations in the type of X-ray detector (energy-integrating, stacked multi-energy channel, and energy discriminating or photon counting), variations in coded aperture pattern type (e.g. periodic, Fresnel zone plate, random or optimized random, uniformly redundant array), material, or thickness. Multiple coded apertures may also be used in combination or by themselves to modulate the detected scatter signal, the choice of which could be controlled automatically given the measurement conditions, e.g., given the geometric constraints of measuring scatter from a user-specified subregion of tissue. Existing mammography systems use digital pixelated area X-ray detectors to measure an X-ray transmission image of the breast of a patient. These include scintillator detectors such as those employing cesium iodide scintillators, or direct conversion detectors such as those employing amorphous selenium. While one of these commonly used energy-integrating X-ray transmission detectors would be sufficient for the present invention, detection of scattered X-rays by an energy differentiating or photon counting detector could provide for improved signal to noise ratio, dose reduction to patient, and overall performance of the system. There are also obvious advantages for scatter measurements to those skilled in the art for embodiments having a curved or staggered area configurations of pixels or detecting elements.
In one embodiment, a spatially resolved volumetric X-ray scatter tomography mammography system is disclosed. The mammography system includes a movable X-ray source for generating a primary X-ray beam for irradiating a breast of a patient. The X-ray source is adjustable based on at least one operating parameter that includes exposure time, current, voltage, or filtration. The mammography system further includes a collimator positioned between the X-ray source and the breast of the patient. The collimator includes an opening that is configurable in at least one dimension to shape the primary X-ray beam. The mammography system further includes a plurality of movable breast plates operable to position the breast of the patient in a path of the primary X-ray beam. The mammography system further includes an X-ray detector array comprising a plurality of X-ray detecting elements. At least some of the X-ray detecting elements are movable. The X-ray detector array is configurable to position at least one X-ray detecting element distally from the X-ray source at a first measurement location in the path of the primary X-ray beam past the breast of the patient to measure transmitted X-ray radiation from the primary X-ray beam. The X-ray detector array is further configurable to position at least one X-ray detecting element distally from the X-ray source at a second measurement location outside the path of the primary X-ray beam past the breast of the patient to measure scattered X-ray radiation from the primary X-ray beam. The mammography system further includes a coded aperture positioned distally from the X-ray source between the breast of the patient and the X-ray detector array. The coded aperture is configured to modulate scattered X-ray radiation from the breast of the patient detected by the X-ray detector array. The mammography system is configurable to perform an X-ray scatter measurement and an X-ray transmission measurement. When performing the X-ray scatter measurement, the X-ray detector array is configured such that at least one X-ray detecting element is positioned out of the path of the primary X-ray beam to detect scattered X-ray radiation from the primary X-ray beam passing through the breast of the patient. When performing the X-ray transmission measurement, the X-ray detector array is configured such that at least one X-ray detecting element is positioned in the path of the primary X-ray beam to detect X-ray radiation transmitted through the breast of the patient. The mammography system further includes a control system comprising memory and a processor. The processor of the mammography system is configured for configuring the mammography system for the X-ray transmission measurement or the X-ray scatter measurement. Configuring the mammography system includes controlling at least one configuration parameter that includes a position of the X-ray source, a position of the X-ray detector array, a dimension of the opening of the collimator, at least one operating parameter of the X-ray source, or a position of at least one of the breast plates.
For the X-ray transmission measurement, the processor of the mammography system is further configured for receiving X-ray transmission data that represents transmitted X-ray radiation detected by the plurality of X-ray detecting elements of the X-ray detector array. The processor of the mammography system is further configured for producing an X-ray radiodensity mammogram image based on the received X-ray transmission data. The processor of the mammography system is further configured for identifying a region of interest in the breast of the patient based on the X-ray radiodensity mammogram image. The processor of the mammography system is further configured for determining at least one scatter configuration parameter for the X-ray scatter measurement based on the identified region of interest in the breast of the patient. The processor of the mammography system is further configured for configuring the mammography system for the X-ray scatter measurement based on the determined at least one scatter configuration parameter.
For the X-ray scatter measurement, the processor of the mammography system is further configured for receiving X-ray scatter data that represents scattered X-ray radiation for the region of interest detected by the plurality of X-ray detecting elements of the X-ray detector array. The processor of the mammography system is further configured for estimating a spatially resolved X-ray scatter spectral reconstruction based on the received X-ray scatter data, the received X-ray transmission data, and the at least one scatter configuration parameter. The processor of the mammography system is further configured for determining a spatially resolved tissue property based on the received X-ray scatter data of the region of interest. The processor of the mammography system is further configured for producing a spatially resolved scatter mammogram image based on the received X-ray transmission data and the received X-ray scatter data.
In one embodiment of the mammography system described herein, for the X-ray scatter measurement, the coded aperture is operable to move to a position distal from the X-ray source between the breast of the patient and the plurality of X-ray detecting elements to modulate the detected scattered X-ray radiation. For the X-ray transmission measurement, the breast of the patient is positioned at a first distance from the X-ray detector array. For the X-ray scatter measurement, the system may be further operable in a magnification mode. In the magnification mode, the breast of the patient is positioned at a second distance from the X-ray detector array. The second distance is greater than the first distance. The processor may be further configured determining a coded aperture configuration parameter that includes a position of the coded aperture during the X-ray scatter measurement of the identified region of interest in the breast of the patient. The processor may be further configured for controlling the position of the coded aperture based on the determined coded aperture configuration parameter.
In one embodiment of the mammography system described herein, the mammography system may further include a beam block configured to block the primary X-ray beam during the X-ray scatter measurement. The beam block is positioned between the breast of the patient and the X-ray detector array in the path of the primary X-ray beam. The beam block may be movable and controllable by the processor, and the processor may be further configured for determining a beam block configuration parameter that includes a position of the beam block during the X-ray scatter measurement of the identified region of interest in the breast of the patient. The processor may be further configured for controlling the position of the beam block based on the determined beam block configuration parameter.
In one embodiment of the mammography system described herein, the mammography system may further include an additional X-ray source. The X-ray source is configured for the X-ray transmission measurement and the additional X-ray source is configured for the scatter measurement.
In one embodiment of the mammography system described herein, the at least one spatially resolved tissue property includes a tissue type that indicates cancerous tissue or benign tissue. The spatially resolved scatter mammogram image includes at least one indication based on the spatially resolved X-ray scatter spectral reconstruction. The at least one indication indicates whether the region of interest includes benign tissue or cancerous tissue.
In one embodiment of the mammography system described herein, the processor may be further configured for generating a colorization of the spatially resolved scatter mammogram image produced based on the received X-ray transmission data and the received X-ray scatter data. The colorization is based on the spatially resolved X-ray scatter spectral reconstruction.
In one embodiment of the mammography system described herein, the processor may be further configured for calculating a spatially resolved estimate of momentum transfer spectra of the breast of region of interest from the received X-ray scatter data. The processor may be further configured for using the spatially resolved estimate of the momentum transfer spectra in the determination of the spatially resolved tissue property. The memory may include a reference library of a plurality of existing tissue momentum transfer spectra. The processor may be further configured for using the reference library of existing tissue momentum transfer spectra in combination with the calculated spatially resolved estimate of the momentum transfer spectra of region of interest to determine the spatially resolved tissue property. The processor may be further configured for using a classification algorithm in the determination of the spatially resolved tissue property. The processor may be further configured for using a machine-learning algorithm in the calculation of the spatially resolved estimate of the spatially resolved tissue property. The processor may be further configured for using a rules-based classification algorithm in the calculation of the spatially resolved estimate of the spatially resolved tissue property.
In one embodiment of the mammography system described herein, at least one of the X-ray detecting elements is used for both the X-ray transmission measurement and the X-ray scatter measurement.
In one embodiment of the mammography system described herein, the processor is further configured for changing the position of the X-ray source to control an angle of incidence of the primary X-ray beam relative to the breast of the patient.
In one embodiment of the mammography system described herein, the at least one operating parameter of the X-ray source is configurable to control an irradiance and an energy spectrum of the primary X-ray beam.
In one embodiment of the mammography system described herein, for the X-ray scatter measurement, at least one of the X-ray detecting elements is configurable for detecting X-ray radiation from the primary X-ray beam transmitted directly through the breast of the patient. The processor may be further configured for receiving X-ray transmission data detected by the X-ray detecting elements that are configured for detecting X-ray radiation from the primary X-ray beam transmitted directly through the breast of the patient. The received X-ray transmission data represents the detected transmitted X-ray radiation during the X-ray scatter measurement. The estimation of the spatially resolved X-ray scatter spectral reconstruction is further based on the received X-ray transmission data detected during the X-ray scatter measurement.
In one embodiment of the mammography system described herein, the processor is further configured for estimating a dose of radiation of the patient during the X-ray scatter measurement and determining the at least one scatter configuration parameter for the X-ray scatter measurement based on the estimated dose of radiation to the patient.
In an embodiment, a method of performing spatially resolved volumetric X-ray diffraction tomography mammography is disclosed. The method includes performing an X-ray transmission measurement. The X-ray transmission measurement is performed by transmitting a first primary X-ray beam from an X-ray source through a collimator having an opening configurable in at least one dimension to shape the first primary X-ray beam and through a breast of a patient positioned between a plurality of breast plates. The X-ray source is adjustable based on at least one operating parameter that includes exposure time, current, voltage, and/or filtration. The X-ray transmission measurement is further performed by detecting X-ray radiation from the first primary X-ray beam transmitted directly through the breast of the patient using a plurality of X-ray detecting elements of an X-ray detector array. At least some of the X-ray detecting elements are movable. The X-ray transmission measurement is further performed by receiving X-ray transmission data via a control system including a processor and memory from the plurality of X-ray detecting elements. The X-ray transmission data represents the detected X-ray radiation from the first primary X-ray beam after the first primary X-ray beam has passed through the collimator and the breast of the patient. The X-ray transmission measurement is further performed by producing a radiodensity mammogram image of the breast of the patient based on the received X-ray transmission data. For example, and not limitation, the radiodensity mammogram image is two-dimensional or three-dimensional. The method further includes identifying a region of interest in the breast of the patient based on the radiodensity mammogram image. The method further includes determining a scatter measurement configuration parameter for an X-ray scatter measurement of the identified region of interest in the breast of the patient. The scatter measurement configuration parameter includes a position of the X-ray source, a position of the plurality of the X-ray detecting elements, a dimension of the opening of the collimator, an X-ray source operating parameter, and/or a position of at least one of the plurality of breast plates. The method further includes performing the X-ray scatter measurement of the region of interest. The X-ray scatter measurement of the region of interest is performed by transmitting a second primary X-ray beam from the X-ray source through the collimator to shape the second primary X-ray beam and through the breast of the patient positioned with the plurality of breast plates. The X-ray scatter measurement of the region of interest is further performed by modulating scattered X-ray radiation from the second primary X-ray beam interacting with the breast of the patient using a coded aperture positioned between the breast of the patient and the plurality of X-ray detecting elements. The X-ray scatter measurement of the region of interest is further performed by detecting the modulated scattered X-ray radiation using the plurality of X-ray detecting elements. The X-ray scatter measurement of the region of interest is further performed by receiving X-ray scatter data representing detected scattered X-ray radiation from the plurality of X-ray detecting elements. The X-ray scatter measurement of the region of interest is further performed by calculating a spatially resolved X-ray scatter spectral reconstruction based on the received X-ray scatter data, the received X-ray transmission data, and the determined scatter measurement configuration parameter. The X-ray scatter measurement of the region of interest is further performed by determining at least one spatially resolved tissue property based on the received X-ray scatter data of the region of interest. The X-ray scatter measurement of the region of interest is further performed by producing a spatially resolved scatter mammogram image based on the received X-ray transmission data and the received X-ray scatter data.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the coded aperture is moved to a position distal from the X-ray source between the breast of the patient and the plurality of X-ray detecting elements to modulate the detected scattered X-ray radiation from the second primary X-ray beam during the X-ray scatter measurement. When performing the X-ray transmission measurement, the breast of the patient is positioned at a first distance from the plurality of the X-ray detecting elements, and when performing the X-ray scatter measurement, a magnification mode is used in which the breast of the patient is positioned at a second distance from the plurality of the X-ray detecting elements. The second distance is greater than the first distance. The method may further include determining, via the processor, a configuration parameter that represents the position of the coded aperture during the X-ray scatter measurement of the identified region of interest in the breast of the patient and controlling, via the processor, the position of the coded aperture.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method may further include blocking the second primary X-ray during the X-ray scatter measurement with a beam block positioned in the path of the second primary X-ray beam between the breast of the patient and the plurality of X-ray detecting elements. The beam block is movable, and when performing the X-ray scatter measurement, the beam block is positioned between the breast of the patient and the X-ray detecting elements in the path of the second primary X-ray beam. The method may further include determining, via the processor, a beam block configuration parameter that represents the position of the beam block during the X-ray scatter measurement of the identified region of interest and controlling, via the processor, the position of the beam block based on the determined beam block configuration parameter.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the X-ray source is used for the X-ray transmission measurement and an additional X-ray source is used for the X-ray scatter measurement.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the at least one spatially resolved tissue property includes a tissue type that indicates cancerous tissue or benign tissue. The spatially resolved scatter mammogram image includes at least one indication based on the spatially resolved X-ray scatter spectral reconstruction. The at least one indication indicates whether the identified region of interest includes benign tissue or cancerous tissue.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes generating a colorization of the spatially resolved scatter mammogram image based on the received X-ray transmission data and the received X-ray scatter data. The colorization is determined based on the spatially resolved X-ray scatter spectral reconstruction.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes calculating a spatially resolved estimate of momentum transfer spectra of the region of interest from the received X-ray scatter data. The method further includes using the spatially resolved estimate of the momentum transfer spectra in the determination of the at least one spatially resolved tissue property. The method may further include using a reference library of a plurality of existing tissue momentum transfer spectra in combination with the calculated spatially resolved estimate of the momentum transfer spectra of the region of interest to determine the at least one spatially resolved tissue property. The method may further include using a classification algorithm when determining the at least one spatially resolved tissue property. The method may further include using a machine-learning algorithm in the calculation of the spatially resolved estimate of the at least one spatially resolved tissue property. The method may further include using a rules-based classification algorithm in the calculation of the spatially resolved estimate of the at least one spatially resolved tissue property.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes using at least one X-ray detecting element for both the X-ray transmission measurement and the X-ray scatter measurement.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes controlling the position of the X-ray source to control an angle of incidence of the first primary X-ray beam or the second primary X-ray beam relative to the breast of the patient.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes configuring at least one operating parameter of the X-ray source to control an irradiance and an energy spectrum of the first primary X-ray beam or the second primary X-ray beam.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes, for the X-ray scatter measurement, receiving X-ray transmission data detected by the X-ray detecting elements that are configured for detecting X-ray radiation from the second primary X-ray beam transmitted directly through the breast of the patient. The received X-ray transmission data represents the detected transmitted X-ray radiation during the X-ray scatter measurement. The calculation of the spatially resolved X-ray scatter spectral reconstruction is further based on the received X-ray transmission data detected during the X-ray scatter measurement. At least one X-ray detecting element is configurable for detecting X-ray radiation from the second primary X-ray beam transmitted directly through the breast of the patient.
In one embodiment of the method of performing spatially resolved volumetric X-ray diffraction tomography mammography, the method further includes, for the X-ray scatter measurement, estimating a dose of radiation to the patient, and determining the at least one scatter configuration parameter for the X-ray scatter measurement based on the estimated dose of radiation to the patient.
Any combination of one or more computer-readable medium(s) may be utilized with the mammography system described herein. The computer-readable medium may be a computer readable signal medium or a computer-readable storage medium (including, but not limited to, non-transitory computer-readable storage media). A computer-readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.
A computer-readable signal medium may include a propagated data signal with computer-readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer-readable signal medium may be any computer-readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.
In one or more exemplary aspects, the instructions may be implemented in hardware, software, firmware, or any combinations thereof. A computer readable medium may provide volatile or non-volatile storage for one or more sets of instructions, such as operating systems, data structures, program modules, applications, or other data embodying any one or more of the methodologies or functions described herein. The computer readable medium may include the memory, the processor, and/or the storage media and may be a single medium or multiple media (e.g., a centralized or distributed computer system) that stores the one or more sets of instructions. Non-transitory computer readable media includes all computer readable media, with the sole exception being a transitory, propagating signal per se. The instructions may further be transmitted or received over the network via the network interface unit as communication media, which may include a modulated data signal such as a carrier wave or other transport mechanism and includes any delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics changed or set in a manner as to encode information in the signal.
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the mammography system described herein has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.
The descriptions of the various embodiments of the mammography system described herein have been presented for purposes of illustration but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
This application claims priority to U.S. Provisional Patent Application No. 63/297,793, entitled “An apparatus and method for in vivo breast tissue imaging used coded aperture X-ray scatter tomography,” which was filed on Jan. 9, 2022, the entire contents of which is incorporated by reference herein in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2023/060302 | 1/9/2023 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63297793 | Jan 2022 | US |
