Method for automatically aligning images and dxa imaging system

Abstract

The present invention relates to a method and a DXA imaging system for automatically aligning images. The present invention provides a system for performing a scan of an internal structure of an object / patient. The system includes a radiation source that operates to emit a radiation beam; a radiation detector that operates to receive the radiation beam and generate an output signal based at least in part on the received radiation beam; and a controller that is in electronic communication with the radiation source and the radiation detector and operates to generate at least one image of the object / patient. The controller further operates to determine an offset of the at least one image relative to an image reference and uses the offset to automatically align the at least one image with the image reference without requiring the operation of the radiation source and the detector to reposition the object / patient being scanned.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to dual-energy x-ray absorptiometry ("DEXA" or "DXA") systems and methods, and more particularly to modes of operation of these types of imaging systems. BACKGROUND

[0002] Bone density imaging systems, such as dual-energy x-ray absorptiometry ("DEXA" or "DXA") systems and devices, among others, include an x-ray source that emits a collimated beam of dual-energy x-rays to image a subject / patient. In such systems, an x-ray detector is positioned relative to the x-ray source so as to receive x-rays that have passed through the subject. The x-ray source and x-ray detector are typically moved in unison along a path that traverses the subject during a scan, and the detector of many such systems typically outputs / generates an electrical signal in response to the received x-rays. In many bone density imaging systems, the electrical output signal of the detector is typically digitized and then used by the bone density imaging system to generate a scan image of the subject. Measurements of x-ray absorption by the imaged subject at two different x-ray energies reveal information about the composition and / or density of the subject when broken down into two selected base materials (e.g., fat / soft tissue and bone).

[0003] In a DXA imaging procedure, as Figure 1 Illustratively shown, the DXA system moves the arm and x-ray source along a portion of the patient's body to be imaged so as to obtain a plurality of pairs of (high energy and low energy) two-dimensional (2D) DXA images of the specified portion of the patient. The DXA system can move the x-ray source and x-ray detector along the patient's body from the head to the toes or along any portion of the body so as to obtain the desired DXA images. Depending on the type of beam generated by the x-ray source (e.g., a straight beam, a fan beam, or a narrow fan beam), the x-ray source and / or detector can be moved directly along the principal axis of the patient's body or in a raster scan pattern so as to enable the x-ray source and detector to image the entire or a specified portion of the patient's body. In certain embodiments, the x-ray source and detector are operated to perform a scan along the entire imaging window of the DXA system, while in other embodiments, the DXA system can operate the x-ray source and detector to perform a scan of multiple individual segments or sweeps of the source and detector across the imaging window.

[0004] In a DXA imaging procedure, as Figure 1 shown, after initial operation of the DXA system, the operator views the initial images produced by the DXA system so as to determine the alignment of the images and, thus, the patient relative to the imaging system. Proper alignment or centering of the field of view (FOV) of the images is essential to ensure that all regions of interest being scanned are represented in the DXA images.

[0005] If the image shows that the patient being imaged and / or the portion of the patient is not aligned with the DXA system, such as relative to a centerline of the imaging window of the DXA system, an image from a prior scan, and / or another best practice guideline for the image, the operator will abort or stop the DXA system with the sweeping imaging procedure and reposition the patient on the DXA system. The operator will then restart the DXA system to obtain a new image of the patient in order to subsequently determine the alignment of the patient with the DXA system. The operator will continue this process until the initial sweep or image of the DXA scan shows the correct alignment of the patient / image with the DXA system.

[0006] This process enables the operator to ensure that the image produced by the DXA system exhibits the desired portion of the patient being scanned to provide the operator with the desired information about the internal bone structure of the patient. However, the number of iterations of the scanning process required to determine the correct positioning of the patient to obtain the desired image alignment, the total amount of x-rays applied to the patient, and the time required to perform the entire imaging process are each undesirable.

[0007] Alternatively, other DXA devices and systems have been developed that operate to produce images or sweeps of individual sections of the patient. These DXA systems / devices operate to image a portion of the patient after each lateral sweep of the x-ray source and detector. The DXA system analyzes the images of the sections to determine where bone exists in the image to enable the DXA system to estimate the location on the subsequent sweep to begin exposing the patient to x-rays to capture the bone in the subsequent image / sweep. However, while these improved DXA systems are able to more concentrate the x-rays applied to the region of interest of the patient, the improved imaging process still does not guarantee that the target body portion is correctly aligned in the final image composed of each of the sweeps that comply with the best practices.

[0008] Accordingly, similar to the prior art DXA systems / devices, to accommodate any misalignment, these improved DXA systems can provide an initial sweep of the patient for the operator to view for determining the alignment of the patient with respect to the DXA system / device, rather than having to perform a full scan as in the prior art DXA systems and / or devices. However, even with the reduced time for alignment determination based on the ability to view the initial sweep rather than the full image, to ascertain the correct alignment of the patient, there is still a need to iteratively pause the DXA system scan, reposition the patient on the DXA system / device, and restart the scan to have the region of interest of the patient correctly positioned within the scan image / sweep.

[0009] Accordingly, it is desirable to develop an automated image alignment system for a DXA imaging system or device to eliminate or significantly reduce the iterative alignment process required in the prior art DXA imaging systems. SUMMARY

[0010] According to one aspect of the example embodiments of the present disclosure, there is provided an automated image alignment system for a DXA imaging system. The automated imaging system is operable to view initial scans or image segments obtained by the DXA imaging system and determine alignment of the individual scans relative to an alignment reference of the alignment system. If one or more of the scans are misaligned relative to the alignment reference, the alignment system can adjust the operation of the x-ray source to correspond to the actual position of the patient on the DXA system / device, thereby aligning subsequent scans with the alignment reference of the alignment system.

[0011] According to still another aspect of the example embodiments of the present disclosure, a DXA imaging system includes a support on which a subject to be imaged is adapted to be positioned; a radiation source movably disposed relative to the support and configured to emit a beam of radiation toward the subject; a detector movably disposed relative to the support and aligned with the radiation source to receive the beam of radiation from the radiation source and generate image data; a controller operably connected to the radiation source and the detector to control movement and operation of the radiation source and the detector, the controller configured to receive and process the image data from the detector to obtain at least one image of the subject; a display operably connected to the controller for presenting information to a user; and a user interface operably connected to the controller to enable input from a user to the controller, wherein the controller is configured to determine an amount of misalignment of the at least one image relative to an image reference and align the at least one image with the image reference.

[0012] According to still another aspect of the example embodiments of the present disclosure, a method for automatically aligning images obtained in performing a DXA imaging procedure of a subject includes the steps of providing a DXA imaging system having a support on which a subject to be imaged is adapted to be positioned; a radiation source movably disposed relative to the support and configured to emit a beam of radiation toward the subject; a detector movably disposed relative to the support and aligned with the radiation source to receive the beam of radiation from the radiation source and generate image data; a controller operably connected to the radiation source and the detector to control movement and operation of the radiation source and the detector, the controller configured to receive and process the image data from the detector; a display operably connected to the controller for presenting information to a user; and a user interface operably connected to the controller to enable input from a user to the controller; positioning the subject on the support; operating the radiation source and the detector to obtain at least one image of the subject; determining an amount of misalignment of the at least one image relative to an image reference; and aligning the at least one image with the image reference.

[0013] These and other exemplary aspects, features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings illustrate the best mode presently contemplated of practicing the invention.

[0015] In the attached figure:

[0016] Figure 1 is a schematic diagram of a method of aligning a patient with a prior art DXA imaging system.

[0017] Figure 2 is a perspective view of a DXA system for performing a bone density scan of a patient according to an exemplary embodiment of the present disclosure.

[0018] Figure 3 According to an exemplary embodiment of the present disclosure Figure 2 Block diagram of a DXA system.

[0019] Figure 4 According to an exemplary embodiment of the present disclosure Figure 2 A schematic diagram of the operation of an image alignment system of a DXA system operating together to align an image acquired by a DXA imaging system with an alignment reference.

[0020] Figure 5 is a diagram showing an exemplary embodiment according to the present disclosure Figure 4 Schematic diagram of an exemplary embodiment of the operation of an image alignment system.

[0021] Figure 6 According to an exemplary embodiment of the present disclosure, Figure 4 Schematic diagram of various alignment references utilized by the image alignment system.

[0022] Figure 7 is a diagram showing an exemplary embodiment according to the present disclosure Figure 4 Schematic diagram of another exemplary embodiment of an image alignment system. DETAILED DESCRIPTION

[0023] One or more specific embodiments will be described below. In order to provide a concise description of these embodiments, not all features of an actual implementation may be described in the specification. It should be understood that, as in any engineering or design project, in the development of any such actual implementation, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as complying with system-related and business-related constraints that may vary between implementations. Furthermore, it should be understood that such development efforts may be complex and time-consuming, but remain a routine task of design, fabrication, and manufacturing for those of ordinary skill having the benefit of this disclosure.

[0024] When introducing elements of various embodiments of the present application, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there can be additional elements other than the listed elements. Additionally, any numerical examples in the following discussion are intended to be non-limiting, and thus additional numerical values, ranges, and percentages are within the scope of the disclosed embodiments. As used herein, the terms "substantially," "generally," and "about" indicate approximations to a ideal desired condition, within reasonable achievable manufacturing and assembly tolerances, in relation to the functional purpose of the component or assembly. Also, as used herein, "electrically coupled," "electrically connected," and "in electrical communication" mean that the referenced elements are directly or indirectly connected such that electrical current can flow from one to the other. The connection can include a direct conductive connection (i.e., without intervening capacitive, inductive, or active elements), an inductive connection, a capacitive connection, and / or any other suitable electrical connection. There can be intervening components. As used herein, the term "real-time" denotes a level of processing responsiveness that a user senses as sufficiently immediate or enables a processor to keep pace with the processing responsiveness of an external process.

[0025] Further, it is important to note that there are multiple variations of the basic functions and components of dual-energy x-ray absorptiometry ("DEXA" or "DXA") systems and / or devices described herein, but the functions and elements presented below in the manner presented with respect to the disclosed DXA systems are intended to broadly cover other configurations and types of DXA systems, such as but not limited to those disclosed in the following U.S. patents: U.S. Patent 10,499,873 entitled System And Method For Performing A Bone Density Scan Of A Patient, U.S. Patent 10,699,405 entitled System And Method For DXA Tomo-Based Finite Element Analysis Of Bones, the disclosures, structures, and methods of operation of which are each expressly incorporated herein by reference for all purposes. Further, while the embodiments disclosed herein are described with respect to dual-energy x-ray absorptiometry ("DEXA" or "DXA"), it will be appreciated that embodiments of the present application can be applicable to other types of medical imaging systems. Further, as will be appreciated, embodiments of the present application related imaging systems can be used to analyze tissue in general, and are not limited to human tissue.

[0026] Reference is now made to Figure 1, showing the main components of a system 10 for performing a scan of the internal composition of a subject / patient 12, such as a bone density scan. As will be appreciated, in embodiments, the system 10 can be a DXA system that functions as a dual-energy bone densitometer capable of performing bone density determinations. Thus, in embodiments, the bone density scan performed by the system 10 can be used to generate a bone mineral content (“BMC”) measurement, a bone mineral density (“BMD”) measurement, a body composition measurement, an atypical femur fracture (“AFF”) measurement, and / or a body thickness measurement. In embodiments, the BMD can be calculated by dividing the BMC by the area of the bone being imaged. During operation of the system 10, in accordance with embodiments of the present application, the subject / patient 12 is scanned with an x-ray beam having a wide band of energy levels to image the internal structure of the subject / patient 12 (e.g., the patient’s bones). The acquired scan images can then be used to diagnose medical conditions, such as osteoporosis. In embodiments, the scan images can be generated in part from the determined bone density information acquired during the dual-energy x-ray scan.

[0027] Thus, and as Figure 2 shown, the system 10 includes an x-ray or radiation source 14 that operates to emit an x-ray or radiation beam 16 and move along a scan path 18, a radiation detector 20 that operates to move along the scan path 18 and receive the radiation beam 16, and a controller 22 that is in electronic communication with the radiation source 14 and the radiation detector 20. As will be described in greater detail below, the controller 22 operates to adjust the radiation beam 16 as the radiation source 14 and the radiation detector 20 move along the scan path 18 such that the flux of the radiation beam 16 at the radiation detector 20 is within a target flux range.

[0028] In exemplary embodiments, the system 10 can also include a support / patient table 24 for providing a horizontal surface for supporting the subject / patient 12 in a supine or lateral position along a longitudinal axis 26, a support member 28, which in embodiments can be a C-arm having a lower end 30 positioned below the table 24 so as to support the radiation source 14 and an upper end 32 positioned above the table 24 so as to support the radiation detector 20. While the radiation source 14 and the radiation detector 20 are shown in Figure 1 as being below and above the patient 12, respectively, it will be appreciated that the positions of the radiation source 14 and the radiation detector 20 can be reversed such that the radiation source 14 and the radiation detector 20 are above and below the patient 12, respectively. In embodiments, the radiation detector 20 can be fabricated, for example, as a multi-element cadmium telluride (“CdTe”) detector that provides energy discrimination. In embodiments, the radiation detector 20 can also be a single-element or multi-element scintillator with photomultiplier for energy discrimination.

[0029] As described above, the radiation source 14 and the radiation detector 20 are moved along the scan path 18 in order to track a series of transverse scans 34 of the patient 12 during which the radiation detector 20 collects dual-energy radiation (e.g., x-ray) data. In embodiments, the transverse scan procedure generates a single scan image or a quantitative data set from a plurality of scan images acquired from the patient 12 full body with the radiation source 14 and the radiation detector 20 longitudinally aligned with the superior-inferior axis of the patient 12 or transversely aligned from side-to-side (e.g., left-to-right) of the patient. As will be appreciated, using transverse motion to scan the patient 12 facilitates minimizing the time between acquisition of adjacent scan images because the transverse direction of the patient 12 full body is shorter than the longitudinal direction of the patient 12 full body. Thus, transverse scanning can reduce the severity of motion artifacts between scan images, which in turn can further improve the accuracy of merging acquired scan images. However, as will be appreciated, in embodiments, the scan path 18 can be a series of longitudinal scans.

[0030] In certain embodiments, the transverse scan motion can be generated by an actuator (not shown) controlled via the translation controller 36, which can be in electronic communication with or form a part of the controller 22. During operation, the radiation source 14 generates / emits / transmits the radiation beam 16, which in embodiments can have a fan shape with a plane parallel to the longitudinal axis 26. However, in other embodiments, the radiation beam 16 can have a fan shape with a plane perpendicular to the longitudinal axis 26. Further, in embodiments, the scan pattern / path 18 can be configured such that there is some overlap (e.g., 10% of the scanned surface area) between successive scan lines 34 of the radiation beam 16. As will be appreciated, in embodiments, the radiation beam 16 can have a straight shape, a fan shape, a cone shape, and / or other shapes suitable for scanning the patient 12.

[0031] In embodiments, the radiation source 14, the radiation detector 20, and the translation controller 36 can be controlled via a controller 22. The controller 22 can be in electronic communication with a terminal device 38 including a display 40, a keyboard 42, and a cursor control device 44 (e.g., a mouse) that allow for input and output of information (e.g., text, images, and / or other forms of data) to and from the system 10. In embodiments, the controller 22 can be located remotely from the terminal device 38. In other embodiments, the controller 22 can be integrated into the terminal device 38. In embodiments, the controller 22 is adapted to perform one or more processing operations. For example, upon the controller 22 receiving data from the radiation detector 20, the bone and tissue information acquired by the radiation detector 20 can be processed and displayed in real-time during a scan session. The display 40 can include one or more monitors that present information (e.g., scan images and bone length images) about the patient 12 to an operator for diagnosis and analysis. The displayed images can be modified, and the display settings of the display 40 are also adjusted manually using the keyboard 42, the mouse 44, and / or touch screen icons on the display 40.

[0032] As will be further appreciated, the system 10 can be configured to operate in a dual-energy mode, a single-energy mode, or a wideband mode. In the single-energy mode, the radiation beam 16 includes a single narrow energy band, e.g., 20 keV - 150 keV. The single-energy mode can provide high resolution scan images. In the dual-energy mode, the radiation beam 16 includes two or more narrow energy bands that can be emitted simultaneously or consecutively. The dual-energy mode can be used to acquire scan images of the entire body of the patient 12 that include information related to the bone and tissue of the body of the patient 12, which in turn can be used to measure bone density and / or other bone and tissue properties or content. In the wideband mode, the radiation beam 16 can include a single wide energy band. As will be appreciated, the system 10 can be able to switch between the various aforementioned modes.

[0033] Turning now to Figure 3 , a block diagram of the system 10 is shown, with the longitudinal axis 26 depicted as extending out of the page, e.g., Figure 3 a longitudinal view of the patient 12 lying down on the table 24 is depicted. As Figure 3As shown, in embodiments, the radiation source 14 can include an x-ray or beam generator 46, an x-ray or beam tube 48, a source current 50, and a source voltage 52. Thus, in embodiments, the beam generator 46 generates / current based on the source current 50 and / or the source voltage 52. The generated current is then fed to the beam tube 48 via an electrical connection 53, resulting in the radiation beam 16. As will be appreciated, the intensity of the radiation beam 16 at the beam tube 48 is determined, at least in part, by the source current 50 and the source voltage 52. Thus, in embodiments, the initial setting of the source current 50 and / or the source voltage 52 can be based on one or more characteristics of the patient 12, e.g., height, weight, body mass index, and / or other appropriate characteristics. For example, in some embodiments, the initial setting of the source current 50 and / or the source voltage 52 can be based, at least in part, on a height and weight chart that correlates various heights and weights with initial settings of the source current 50 and / or the source voltage 52. As will be appreciated, in embodiments, the initial source current 50 can be between about 0.1 mA and 3 mA.

[0034] As will be appreciated, as the beam 16 moves along the scan path, the flux at the radiation detector 20 changes. For example, in embodiments, when the beam 16 has fully reached the right or left side of the patient 12 such that the beam 16 does not pass through the patient 12, i.e., when the beam 16 is “scanning in air,” the intensity of the beam 16 at the detector 20 (i.e., the flux) is substantially the same as the intensity of the beam 16 at the tube 48. In other words, the body of the patient 12 does not absorb and / or deflect the rays / photons from the beam 16. As the beam 16 begins to move throughout the patient 12 (e.g., right to left), some of the rays / photons within the beam 16 are absorbed and / or deflected by the body of the patient 12, such that the intensity of the beam 16 at the detector 20 (e.g., the flux) is less than the intensity of the beam 16 at the tube 48. As the beam 16 continues to pass through the patient 12, the flux of the beam 16 at the detector 20 changes with the changes in thickness and density of the body of the patient 12.

[0035] As noted above, in embodiments, the controller 22 adjusts the radiation beam 16 such that the flux (i.e., the intensity of the beam 16 at the detector 20) is within a target flux range as the radiation source 14 and the radiation detector 20 move along the scan path 18. As will be appreciated, in embodiments, the controller 22 can adjust the beam 16 and / or the target flux range in real-time can be between about 20 counts / second - 100,000 counts / second. As used herein, the term “counts” means the detection of photons by the radiation detector 20, e.g., 100 counts / second means that the radiation detector 20 detected 100 photons from the radiation beam 16 over a duration of one (1) second. Further, the data storage device / recorder 64 is in electronic communication with the controller 22 and operates to store data transmitted from the detector 20, operational commands for operation of the system 10, and other related information for operation of the system 10.

[0036] As Figure 3 Further shown, the controller 22 can include a flux translator 54 that adjusts the intensity of the beam 16 based on the output signal 58 of the detector 20. In other words, in embodiments, the flux translator 54 translates the output signal 58 into a desired beam 16 intensity at the tube 48 based on the desired flux at the radiation detector 20. In embodiments, the flux translator 54 can adjust the intensity of the beam 16 via adjusting the source current 50 and / or the source voltage 52. For example, if the controller 22 determines that the flux at the detector 20 is too high, e.g., greater than or equal to 100,000 counts / second, the flux translator 54 can decrease the source current 50 and / or the source voltage 52. Conversely, if the controller 22 determines that the flux at the detector 20 is too low, e.g., less than or equal to 20 counts / second, the flux translator 54 can increase the source current 50 and / or the source voltage 52.

[0037] As will be appreciated, in embodiments, the output signal 58 generated by the radiation detector 20 can be a voltage and / or a current, to include direct current (“DC”) and alternating current (“AC”), modulated by the radiation detector 20 in response to the amount of flux of the beam 16 as measured / sensed by the radiation detector 20. In embodiments, the output signal 58 can be an analog or digital signal that encodes the flux level of the beam as measured / determined by the radiation detector 20. For example, in embodiments, the output signal 58 can encode the flux of the beam 16 at the radiation detector as a range between about 0.95 mA to 1.0 mA.

[0038] Referring now to Figure 4When the DXA system 10 is operated to scan the patient 12, as previously described, the radiation source 14 is operated to emit the beams 16 through the patient 12 and to contact the detector 20 as it moves relative to the patient 12 along a defined path. Information obtained from the beams 16 as they contact the detector 20 is used by the controller 22 to generate an image 100 of the area of the patient 12 scanned by the beams 16 in a known manner. After each pass, scan, or sweep of the radiation source 14 through the patient 12 body, the controller 22 will generate a swept image 100 for representation on the display 40. In generating the swept image 100, the controller 22 will analyze the swept image 100 to determine the positioning or representation of bone within the swept image 100. Using this positioning or location of bone in the swept image 100, the controller 22 can adjust the operation of the radiation source 14 to limit the emission of the beams 16 from the source 14 to the area directly beneath and adjacent to the bone structure of the patient 12 to be imaged so as to produce relevant image data on the detector 20 without overexposing the patient 12 to the beams 16 from the source 14 throughout the field of view (FOV) 102 of the DXA system 10.

[0039] In generating the swept image 100 in real time to enable adaptation to the operation of the source 14 continuously sweeping during the scan being performed, the controller 22 will also present a representation of each swept image 100 on the display 40 of the DXA system 10. The controller 22 can additionally position the positioning of the swept image 100 relative to the FOV 102 so that the controller 22 of the DXA system 10 can determine the alignment of the swept image 100 relative to the FOV 102, such as by determining the alignment of the anatomical structures contained in the swept image 100 relative to the FOV 102.

[0040] In one exemplary embodiment of the present disclosure, the controller 22 initially compares the first swept image 100 or any other number of initial swept images 100 to an image reference 104 ( Figure 5 ) in order to determine whether the swept image 100 is misaligned with the FOV 102, such as due to a mispositioning of the patient 12 on the DXA system 10 (e.g., the table 24). As Figure 5 and Figure 6 shown, the image reference 104 can take a variety of different forms, such as a geometric representation 106 of the FOV 102, a representative anatomical model 108 of the body of the patient 12, or a prior scan image 110 of the patient 12, each of which is properly aligned with the FOV 102 of the DXA system 10 (e.g., with the centerline 116 of the FOV 102).

[0041] Regardless of the form of the image reference 104, in operation of the DXA system 10 to perform image alignment, initially the controller 22 compares the positioning of the initial swept image 100 with the image reference 104. If it is determined that the swept image 100 is misaligned relative to the image reference 104, the controller 22 determines the difference between the actual positioning of the swept image 100 and the expected or aligned positioning relative to the image reference 104, optionally in real time as the initial swept image 100 is obtained. This process can be performed automatically by the controller 22, without the need to pause and / or abort the ongoing scan, reposition the subject / patient 12 on the support / table 24, and restart the scan, as in prior art systems and methods.

[0042] like Figure 5 As shown, in one exemplary embodiment, the determination of a difference between the actual position of the swept image 100 and the aligned position can be performed by ascertaining the position of a structure and / or anatomical landmark 112 of the object / patient 12 (such as the iliac crest) in the swept image 100 compared to the position or location of the same landmark 112 present in a previously scanned image 110 of the patient 12. Using the difference in the position of the landmark 112 in the swept image 100 and the previously scanned image 110, the controller 22 can determine an offset 114 in the position of the patient 12 relative to a centerline 116 of the FOV 102 of the DXA system 10 due to the incorrect positioning of the patient 12, if the previously scanned image 110 had previously been aligned with the FOV 102 of the DXA system 10. Once the offset 114 is determined, the controller 22 can shift the position of the swept image 100 relative to the FOV 102 in order to align the swept image 100 about the centerline 116.

[0043] In one alternative embodiment, employed alone or in combination with other embodiments, the offset 114 can be determined by the controller 22 using a comparison of the landmarks 112 in the swept image 100 with other image references 104, such as a representative anatomical model / generalized representation 108 of the body of the patient 12. In another alternative embodiment, employed alone or in combination with other embodiments, the offset 114 can be determined by comparing information about the portion of the FOV 102 within which the source 104 operates to obtain the swept image 100 with a known location of the FOV 102, such as by using a geometric representation 106 of the FOV 102.

[0044] Further, for the known offset 114 of the position of the swept images 100, the controller 22 can utilize the offset 114 to correct all subsequent swept images 100 to properly align the swept images 100 with the FOV 102. In one embodiment, the controller 22 can shift the positioning of each continuously obtained swept image 100 by the offset 114 either in real-time as each swept image 100 is obtained or after all of the swept images 100 have been obtained. Alternatively, the controller 22 can shift the operation of the source 104 by the amount of the offset 104 relative to the FOV 102 to shift the position of the swept images 100 to align with the FOV 102.

[0045] In another exemplary embodiment, where the image reference 104 is used to determine the positioning of the patient 12 relative to the FOV 102 to place the desired region of the patient 12 to be imaged entirely outside of the FOV 102, the controller 22 can operate to automatically abort the scanning process and optionally provide a suitable indication of the positioning problem to an operator.

[0046] Reference is now made to Figure 7 In another exemplary embodiment of the present disclosure, the DXA system 10 includes an optical camera 120 disposed proximate to the table 24 of the DXA system 10. The camera 120 is connected to the controller 22 and is operable to obtain visual images of the table 24 and the position of the positioning of the patient 12 on the table 24. These images from the camera 120 can be used by the controller 22 to determine the FOV 102 of the DXA system 10. With the information of the FOV 120 from the camera 120, the controller 22 can determine various structural and / or anatomical landmarks 124 of the subject / patient 12 relative to the FOV 102 in known manners using artificial intelligence (“AI”) and / or computer vision system tools. Those landmarks 124 can then be used by the controller 22 to determine the initial scan starting point 122 to provide the swept images 100 of the desired region of the patient 12. Further, similar to the landmarks 112, the landmarks 124 can be used by the controller 22 to determine the offset 114 for aligning the swept images 100 of the subject / patient 12. These landmarks 124 can additionally be obtained via sources other than the camera 120, such as pressure sensitive pads or capacitive panels or matrices (not shown) disposed on the table 24 that are contacted by the patient 12. Using the determined actual position of the landmarks 124 from the information obtained from the pads or panels relative to the actual FOV 102, i.e., the positioning of the patient 12, the controller 22 can determine the scan region 116 within which the swept images 100 will be obtained for the desired region of the patient 12.

[0047] Finally, it should be understood that the system 10 can include necessary electronics, software, memory, storage, databases, firmware, logic / sate machines, microprocessors, communication links, displays or other visual or audio user interfaces, printing devices, and any other input / output interfaces adapted to perform the functions and / or processes described herein. For example, as previously described, the system can include at least one processor and system memory / data storage structures, which can include random access memory (RAM) and read-only memory (ROM). The at least one processor of the system can include one or more conventional microprocessors and one or more supplementary co-processors, such as math co-processors and the like. The data storage structures discussed herein can include an appropriate combination of magnetic, optical and / or semiconductor memory, and can include, for example, RAM, ROM, flash drive, optical discs and / or hard disk or drive.

[0048] Additionally, a software application adapted to execute the methods disclosed herein can be read into the main memory of at least one processor from a computer-readable medium. As used herein, the term "computer-readable medium" refers to any medium that provides or participates in providing instructions to the at least one processor (or any other processor of any other device discussed herein) of the system 10 for execution. Such a medium can take many forms, including but not limited to non-volatile media and volatile media. Non-volatile media includes, for example, optical, magnetic, or magneto-optical disks, such as a storage device. Volatile media includes dynamic random access memory (DRAM), which typically constitutes the main memory. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, a hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, RAM, PROM, EPROM, a FLASH- EPROM, any other memory chip or cartridge, a carrier wave, or any other medium from which a computer can read.

[0049] While in embodiments, execution of sequences of instructions in the software applications causes the at least one processor to perform the methods / processes described herein, hard-wired circuitry can be used in place of, or in combination with, software instructions for implementation of the methods / processes of the present application. Thus, embodiments of the present application are not limited to any specific combination of hardware and / or software.

[0050] It should be understood that the foregoing described aspects, embodiments and implementations of the present disclosure are merely exemplary and are not limiting, as these can vary. It is also to be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only, and is not intended to limit the scope of the present disclosure which will be limited only by the appended claims.

Claims

1. A method for automatically aligning images obtained when performing a DXA imaging procedure on a subject, the method comprising the steps of: a. Providing a DXA imaging system, the DXA imaging system comprising: i. a support member on which the object to be imaged is positioned; ii. a radiation source movably disposed relative to the support and configured to emit a radiation beam toward the object; iii. a detector movably disposed relative to the support member and aligned with the radiation source to receive the radiation beam from the radiation source and generate image data; iv. a controller operatively connected to the radiation source and the detector to control movement and operation of the radiation source and the detector, the controller being configured to receive and process image data from the detector; v. a display operatively connected to the controller for presenting information to a user; and vi. a user interface operatively connected to the controller to enable user input to the controller; b. positioning the object on the support member; c. operating the radiation source and the detector to obtain at least one image of the object; d. determining an offset of said at least one image relative to an image reference; and e. Applying the offset to the at least one image to shift the position of the at least one image relative to the field of view of the DXA imaging system, thereby aligning the at least one image with the image reference.

2. The method according to claim 1, further comprising the steps of: The offset is applied to subsequent images acquired by the DXA imaging system to align the subsequent images with the image reference.

3. The method of claim 2, wherein the step of applying the offset to subsequent images acquired by the DXA imaging system comprises: The subsequent images are shifted in position relative to the field of view of the DXA imaging system. The method of claim 1 , wherein the image reference is a previously scanned image of the object. The method of claim 4 , wherein the object is at least a part of a patient's body.

6. The method of claim 5, wherein the step of determining the offset comprises the steps of: a. locating at least one landmark in said at least one image; b. comparing the position of the at least one landmark in the at least one image with the positioning of the same landmark in the previously scanned image; as well as c. Determining a difference between the position of the landmark in the at least one image and the location of the landmark in the previously scanned image to define the offset.

7. The method of claim 5, wherein the step of determining the offset comprises the steps of: a. locating at least one landmark in said at least one image; b. comparing the position of the at least one landmark in the at least one image with the positioning of the same landmark in the generalized representation of the shape of the object; as well as c. Determining a difference between the position of the landmark in the at least one image and the location of the landmark in the generalized representation to define the offset.

8. The method according to claim 1 , wherein the step of determining the offset of the at least one image relative to an image reference comprises the steps of: a. locating at least one landmark in said at least one image; b. comparing the position of the at least one landmark in the at least one image with the positioning of the same landmark in the image reference; c. determining whether the desired area of ​​the object to be imaged is located outside the field of view of the DXA imaging system so that an offset cannot be determined; and d. suspending said operation of said radiation source.

9. The method according to claim 1, further comprising the steps of: a. operating an optical camera connected to the controller to obtain a visual representation of the positioning of the object on the support member after positioning the object on the support member; b. determining structural landmarks of the object relative to the field of view of the DXA imaging system; as well as c. Determining a starting point for said operation of said radiation source to obtain said at least one image of said object.

10. The method of claim 1 , wherein determining the offset of the at least one image relative to the image reference and aligning the at least one image with the image reference occur in real time relative to operating the radiation source and the detector to obtain at least one image of the object.

11. The method according to claim 10, further comprising the steps of: The offset is applied to subsequent images acquired by the DXA imaging system in real time relative to the step of acquiring subsequent images by the DXA imaging system to align the subsequent images with the image reference.

12. A DXA imaging system, comprising: a support member, the object to be imaged is suitable for positioning on the support member; b. a radiation source movably disposed relative to the support and configured to emit a radiation beam toward the object; c. a detector movably disposed relative to the support and aligned with the radiation source to receive the radiation beam from the radiation source and generate image data; d. a controller operatively connected to the radiation source and the detector to control movement and operation of the radiation source and the detector, the controller being configured to receive and process image data from the detector to obtain at least one image of the object; e. a display operatively connected to the controller for presenting information to a user; as well as f. a user interface operatively connected to the controller to enable user input to the controller; wherein the controller is configured to determine an offset of the at least one image relative to an image reference and apply the offset to the at least one image to shift the position of the at least one image relative to the field of view of the DXA imaging system, thereby aligning the at least one image with the image reference.

13. The imaging system of claim 12, wherein the image reference is selected from: a geometric representation of the field of view of the DXA imaging system, a generalized representation of the shape of the object, or a previously scanned image of the object.

Images