Filter systems and methods for imaging a subject

Abstract

A method and system for acquiring image data of a subject is disclosed. Image data can be collected with an imaging system having selected filtering characteristics. Image data can be reconstructed using a reconstruction technique.

Description

[0001] Cross-reference to related applications

[0002] This application includes subject matter similar to that disclosed in concurrently filed U.S. Patent Application 4:23;3 / 6<; (Attorney’s File No. 5074A-000227-US). The entire disclosure of each of the foregoing applications is incorporated herein by reference. Technical Field

[0003] This disclosure relates to imaging a subject, and more particularly to a system for acquiring image data using a selected filter system. Background Technology

[0004] This section provides background information in connection with this disclosure, which is not necessarily prior art.

[0005] Subjects (such as human patients) may undergo surgery to address problems in their anatomy. Surgery may include various procedures such as bone repositioning or reinforcement, insertion of implants (i.e., implantable devices) or other appropriate procedures.

[0006] Images of the subject can help surgeons plan and execute procedures. Surgeons can select a two-dimensional or three-dimensional image representation of the subject based on images acquired from imaging systems such as magnetic resonance imaging (MRI), computed tomography (CT), fluorescence examination (e.g., C-arm imaging), or other appropriate imaging systems. By allowing surgeons to observe the subject's anatomy without removing covering tissues (including skin and muscle tissue), images can help surgeons perform procedures using less invasive techniques. Summary of the Invention

[0007] This section provides an overall overview of this disclosure and is not a complete disclosure of its full scope or all of its features.

[0008] According to various embodiments, the imaging system acquires image data of a subject (such as a living patient, e.g., a human patient). The imaging system may acquire image data using multiple energy sources. As an alternative to or in addition to multiple energy emission systems, the imaging system may also include filter components. The filter may, for example, use the projection of the subject to enhance or select the beam or emission (e.g., an X-ray beam) used to generate image data. The imaging system may include those disclosed in U.S. Patent Application Publication 2018 / 0310899 (published November 1, 2018, entitled "FILTER SYSTEM AND METHOD FOR IMAGING ASUBJECT"), which is incorporated herein by reference.

[0009] Enhanced or selected contrast imaging may include injecting and / or applying a contrast agent to the subject using one and / or more energies. Additionally, various filters may be used individually or in combination with the contrast agent at selected times. Therefore, multiple image projections can be obtained with or without contrast agent and / or with or without one or more selected filters.

[0010] An imaging system with multiple energies may include portions that operate with different parameters, allowing the emission of multiple beams with different characteristics. Thus, the beams may have characteristics based on selected parameters and / or have selected energy parameters. In various embodiments, the imaging system may include a first energy source having one or more first energy parameters and one or more second energy sources under a second energy parameter to excite the source. Furthermore, the imaging system may include multiple sources (each source may have the same trajectory or path), wherein each source includes one or more different features or portions to achieve the first energy parameter and the second energy parameter (e.g., voltage) to provide emitted beams with different energy characteristics (e.g., X-rays).

[0011] Imaging systems with filters may include one or more filters to ensure and / or help ensure proper or selected separation between a first energy characteristic and a second energy characteristic. The first energy characteristic may be selected to provide a first X-ray spectrum having the first energy characteristic and a second X-ray spectrum having the second energy characteristic. Filters may be provided at selected times to help ensure appropriate or selected spectra used for imaging the subject, such as eliminating possible or actual overlap of the X-ray spectra.

[0012] One or more filters can also be used for various purposes when acquiring selected image projections. Filters can be used to generate multiple image projections with a single broadband beam. Selected filters can also be used to help detect and / or correct various aberrations and / or distortions.

[0013] Further areas of applicability will become apparent from the description provided herein. The descriptions and specific examples in this overview are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0014] The accompanying drawings described herein are for illustrative purposes only, representing selected embodiments and not all possible specific implementations, and are not intended to limit the scope of this disclosure.

[0015] Figure 1 This is an environmental view of the imaging system in the operating room;

[0016] Figure 2 This is a schematic diagram of a filter assembly according to various implementation schemes;

[0017] Figure 3A and Figure 3B It is a schematic diagram of an imaging system including a source assembly, a filter assembly, and a detector according to various implementation schemes;

[0018] Figure 4 It is a flowchart of a method for operating an imaging system with a filter assembly;

[0019] Figure 5 It is a schematic diagram of an imaging system including a source assembly according to various implementation schemes;

[0020] Figure 6A and Figure 6B This is a schematic diagram of an imaging system with different configurations of filter assemblies according to various implementation schemes;

[0021] Figure 7 This is a schematic diagram of a filter assembly according to various implementation schemes;

[0022] Figure 8 These are schematic diagrams of imaging systems based on various implementation schemes; and

[0023] Figure 9 This is an exemplary illustration of a projection obtained using the selected filter configuration.

[0024] In several views of all the accompanying drawings, the corresponding reference numerals indicate the corresponding parts. Detailed Implementation

[0025] Exemplary embodiments will now be described more fully with reference to the accompanying drawings.

[0026] refer to Figure 1 In the operating room or operating room 10, a user (such as surgeon 12) can perform procedures on a subject (such as patient 14). During the procedure, user 12 can use imaging system 16 to acquire image data of patient 14, allowing a selected system to generate or create images to aid in the procedure. Models (such as three-dimensional (3D) images) can be generated using the image data and displayed as image 18 on display device 20. Display device 20 may be part of and / or connected to processor system 22, which includes input device 24 (such as a keyboard) and processor module 26, which may include one or more processors or microprocessors (e.g., central processing unit, graphics processing unit, etc.) combined with processor system 22, and a non-transitory and / or transient memory module 27 of selected type. A connection 28 may be provided between processor 26 and display device 20 for data communication to allow driving display device 20 to display or show image 18.

[0027] Imaging system 16 may include those sold by Medtronic Navigation, Inc., which has a place of business in Louisville, Colorado, USA. Imaging systems. Including Imaging system 16 or other suitable imaging system may be used during the selected procedure, such as the imaging system described in U.S. Patent Publications 2012 / 0250822, 2012 / 0099772 and 2010 / 0290690, which are incorporated herein by reference.

[0028] Imaging system 16 may include a mobile cart 30. Imaging system 16 may also include a controller and / or control system 32. In various embodiments, controller 32 may be incorporated into mobile cart 30 (if present). Control system may include processor module 33a and memory module 33b (e.g., tangible non-transitory memory). Memory 33b may include various instructions executed by processor 33a to control the imaging system (including the various parts of imaging system 16). Control system may include a processor (such as a general-purpose processor or a specific application processor) and a memory system (e.g., tangible non-transitory memory, such as a rotary disk or solid-state non-volatile memory). For example, memory system may include instructions to be executed by processor to perform functions and determine results, as discussed herein.

[0029] The imaging system 16 may also include an imaging stage 34 in which a source unit 36 ​​and a detector 38 are positioned. The stage 34 may be connected to a mobile trolley 30. The stage may be O-shaped or annular, wherein the stage is substantially annular and includes walls forming volumes in which the source unit 36 ​​and detector 38 can move.

[0030] The mobile trolley 30 can be moved from one operating room to another, and the table 34 can be moved relative to the trolley 30, as discussed elsewhere herein. This allows the imaging system 16 to be movable and capable of moving relative to the subject 14. Thus, the imaging system 16 can be used in multiple locations and for multiple procedures without requiring capital expenditure or space dedicated to a fixed imaging system.

[0031] Source unit 36 ​​may be an X-ray emitter that emits X-rays through patient 14 for detection by detector 38. As will be understood by those skilled in the art, the X-rays emitted by source 36 may be cone-shaped and detected by detector 38. Source 36 / detector unit 38 are generally diametrically opposed within gantry 34. Detector 38 may move 360° around patient 14 within gantry 34, while source 36 remains approximately 180° opposite detector 38 (e.g., using a fixed internal gantry or a moving system). Additionally, gantry 34 may be generally positioned relative to subject 14, which may be placed on a patient support frame or worktable 15, such as... Figure 1 The device 16 can move equidistantly in the direction of arrow 40 shown. The gantry 34 can also tilt relative to the patient 14, as indicated by arrow 42, and move longitudinally along line 44 relative to the longitudinal axis 14L of the patient 14 and the trolley 30. It can also move vertically relative to the trolley 30 and laterally relative to the patient 14, typically along line 46, to allow the source 36 / detector 38 to be positioned relative to the patient 14. The imaging device 16 can be precisely controlled to move the source 36 / detector 38 relative to the patient 14 to generate accurate image data of the patient 14. The imaging device 16 can be connected to the processor 26 via connection 50, which may include a wired or wireless connection or physical medium transmission from the imaging system 16 to the processor 26. Therefore, image data collected using the imaging system 16 can be transmitted to the processing system 22 for navigation, display, reconstruction, etc.

[0032] As discussed herein, source 36 may include one or more X-ray sources for imaging subject 14. In various embodiments, source 36 may include a single source that may be powered by more than one power source to generate and / or emit X-rays with different energy characteristics. Furthermore, more than one X-ray source may be source 36 that can be powered to emit X-rays with different energy characteristics at selected times. Dual-energy imaging systems may include those described in U.S. Patent Application Publications 2012 / 0099768 and 2012 / 0097178, both of which are incorporated herein by reference.

[0033] According to various embodiments, the imaging system 16 can be used with non-navigation or navigation procedures. In navigation surgery, locators and / or digitizers, including any one or both of optical locators 60 and electromagnetic locators 62, can be used to generate fields and / or receive and / or transmit signals within a navigation domain relative to the patient 14. The navigation space or navigation domain relative to the patient 14 can be registered with image 18. As understood in the art, correlation allows for registration between the navigation space defined within the navigation domain and the image space defined by image 18. A patient tracker or dynamic reference frame 64 can be attached to the patient 14 to allow dynamic registration and maintain the registration of the patient 14 with image 18.

[0034] The patient tracking device or dynamic registration device 64 and the instrument 66 can then be tracked relative to the patient 14 to allow for navigation procedures. The instrument 66 may include tracking devices (such as optical tracking device 68 and / or electromagnetic tracking device 70) to allow tracking of the instrument 66 using either or both of the optical locator 60 or the electromagnetic locator 62. The instrument 66 may include a communication line 72 with a navigation / detection interface device 74, such as an electromagnetic locator 62 with a communication line 76 and / or an optical locator 60 with a communication line 78. Using communication lines 74, 78 respectively, the interface 74 can then communicate with the processor 26 via a communication line 80. It should be understood that any communication line 28, 50, 76, 78, or 80 can be wired, wireless, physically transmitted or mobile, or any other suitable communication. However, a suitable communication system may be equipped with a corresponding locator to allow tracking of the instrument 66 relative to the patient 14, thereby allowing the illustrated instrument 66 to be tracked relative to image 18 for surgical procedures.

[0035] Those skilled in the art will understand that device 66 can be any suitable device (such as a ventricular or vascular stent, spinal implant, neural stent or stimulator, ablation device, or the like). Device 66 can be an interventional device, or may include or be an implantable device. Tracking device 66 allows viewing the position (including x, y, z position and orientation) of device 66 relative to patient 14 using registered images 18 without having to directly view device 66 within patient 14.

[0036] Furthermore, the stage 34 may include an optical tracking device 82 and / or an electromagnetic tracking device 84 for tracking using a corresponding optical locator 60 or electromagnetic locator 62. Thus, the imaging device 16 can be tracked relative to the patient 14, and the instrument 66 can also be tracked to allow initial registration, automatic registration, or continued registration of the patient 14 relative to the image 18. Registration and navigation procedures are discussed in U.S. Patent No. 8,238,631, which is incorporated herein by reference. After registering and tracking the instrument 66, an icon 174 may be displayed relative to the image 18 (including overlaid on the image). In short, registration involves a transformation between image space and patient space to allow the tracking object (e.g., instrument 66) to be illustrated relative to the image 18 (e.g., overlaid on the image).

[0037] Steering Reference Figure 2According to various embodiments, source 36 may include a single x-ray tube 100, which may be connected to switch 102, which interconnects a first power supply A 104 and a second power supply B 106 with x-ray tube 100. X-rays may be emitted from x-ray tube 100 in a selected shape or configuration (such as a cone), which may be centered on a ray or line 110 directed at detector 38. Switch 102 may switch between power supply A 104 and power supply B 106 to power x-ray tube 100 with different power parameters (such as selected and different voltages and / or amperes) to emit x-rays toward detector 38 with different energy characteristics generally in the direction of vector 110. Vector 110 may be a central vector or ray within the x-ray beam. Vector 110 may include a selected line or axis associated with further interaction of the beam (such as with filter components), as discussed further herein.

[0038] However, it will be understood that switch 102 may also be connected to a single variable power source capable of providing power characteristics at different voltages and / or ampere numbers, rather than switch 102 connected to two different power sources A 104 and / or B 106. Furthermore, switch 102 may be a switch for switching a single power source between different voltages and ampere numbers. Additionally, source 36 may include more than one source configured or operable to emit X-rays with more than one energy characteristic. The switch or selected system may operate to power two or more X-ray tubes to generate X-rays at selected times.

[0039] Patient 14 can be positioned within the x-ray beam to allow image data of patient 14 to be acquired based on the emission of x-rays toward detector 38 in the direction of vector 110.

[0040] Using a beam (e.g., an X-ray beam) with more than one power or energy characteristic (e.g., dual power characteristics) to acquire a projection allows for enhanced and / or dynamic contrast reconstruction of a model of subject 14 based on the acquired image data of patient 14. However, it should be understood that more than two power sources may be provided, or they may be altered during operation to provide X-rays with more than two energy characteristics. In addition to and / or as an alternative to more than one source and / or power source, a filter assembly 200 may be provided to aid in and / or generate the acquisition of a projection with multiple power parameters. Unless specifically stated otherwise, the discussion herein of two or dual energy is merely exemplary and not intended to limit the scope of this disclosure.

[0041] Furthermore, imaging system 16 can be used to generate one or more models using one or more projections. Processor modules 24, 33a can execute selected instructions to generate the model. The instructions may include iterative or algebraic processes that can be used to reconstruct a model of at least a portion of patient 14 (such as for image 18) based on the acquired image data. It should be understood that the model may include a three-dimensional (3D) rendering of the imaging portion of patient 14 based on the image data. The rendering may be formed or generated based on selected techniques, such as those discussed herein.

[0042] The x-ray tube 100 can be used to generate a two-dimensional (2D) x-ray projection of the patient 14, a selected portion of the patient 14, or any region, area, or volume of interest. The 2D x-ray projection can be reconstructed as discussed herein to produce and / or display a three-dimensional (3D) volumetric model of the patient 14, a selected portion of the patient 14, or any region, area, or volume of interest. As discussed herein, the 2D x-ray projection can be image data acquired using the imaging system 16, while the 3D volumetric model can be generated or modeled from the image data.

[0043] To reconstruct or form a 3D volumetric image, appropriate algebraic techniques include Expectation Maximization (EM), Ordered Subset EM (OS-EM), Simultaneous Algebraic Reconstruction Technique (SART), and Total Variation Minimization (TVM), as generally understood by those skilled in the art. Applications performing 3D volumetric reconstruction based on 2D projections allow for efficient and complete volumetric reconstruction. Typically, algebraic techniques may involve iterative processes to perform a reconstruction of patient 14 for display as image 18. For example, projections of pure or theoretical image data, such as those based on or derived from atlases or stylized models of a "theoretical" patient, can be iteratively modified until the theoretical projected image matches the acquired 2D projected image data of patient 14. The stylized model can then be appropriately modified into a 3D volumetric reconstruction model of the acquired 2D projected image data of the selected patient 14 and can be used for surgical procedures, such as navigation, diagnosis, or planning. Theoretical models can be associated with theoretical image data to construct theoretical models. In this way, the model or image data 18 can be constructed based on image data of patient 14 acquired using imaging device 16.

[0044] 2D projected image data can be acquired by moving the source / detector 36 / 38 around the patient 14 in a substantially circular or 360° directional motion around the patient 14, as the source / detector 36 / 38 moves individually or in conjunction with the movement of the stage 34. The optimal motion can be a predetermined movement of the source / detector 36 / 38 within a circle, as described above. The optimal motion can also be a motion that allows for the acquisition of sufficient image data to reconstruct a selected quality of image 18. This optimal movement can allow for the acquisition of a selected amount of image data by moving the source / detector 36 / 38 along a path to minimize, or attempt to minimize, the x-ray exposure of the patient 14 and / or user 12 without requiring additional or substantially more x-ray exposure.

[0045] Furthermore, due to the movement of the gantry 34, the detector never needs to move in a perfectly circular motion, but can instead move in a spiral or other rotational motion around or relative to the patient 14. Moreover, based on the movement of the imaging system 16 (including the gantry 34 and detector 38 together), the path can be substantially asymmetric and / or nonlinear. In other words, the path does not need to be continuous, because detector 38 and gantry 34 can stop, move backward (e.g., oscillate), etc., while following an optimal path. Therefore, detector 38 never needs to travel a full 360° around the patient 14, because gantry 34 can tilt or otherwise move and detector 38 can stop and move back in the direction it has already traveled.

[0046] When acquiring image data at detector 38, the selected energy X-rays typically interact differently with the tissues and / or contrast agents in patient 14, based on the properties of the tissues or contrast agents in patient 14 and the energies of the two X-ray beams emitted by X-ray tube 100. For example, the soft tissues of patient 14 may absorb or scatter X-rays with a first energy, which differs from X-rays with a second energy. Similarly, contrast agents (such as iodine) may absorb or scatter X-rays at a first energy, which differs from X-rays at a second energy. Different energy X-rays can be used to distinguish and / or differentiate between different types of material properties (e.g., hard or soft anatomical structures or two types of soft anatomical structures (e.g., blood vessels and surrounding tissues)), contrast agents, implants (e.g., metallic implants), and surrounding natural anatomical structures (e.g., bone) within patient 14. By switching between two or more power parameters and knowing the time of X-ray generation, the information detected at detector 38 can be used to identify or separate different types of anatomical structures or contrast agents being imaged.

[0047] Because the x-ray tube 100 is in a movable imaging system, such as imaging system 16, it can move relative to the patient 14. Therefore, as the x-ray tube 100 moves relative to the patient 14, the energy of the x-rays reaching or attenuating the patient 14 is being altered or changed. Consequently, the image projection acquired using the first energy may not be in the same pose or position relative to the patient 14 as with the second energy. However, if it is desired or preferred that the model be formed from a single position within the patient 14, various interpolation techniques can be used to generate the model. Interpolation can occur between the first and second acquired image data. The first and second image data can be generated using two different energies. Therefore, interpolation between the acquired image data can be used to form a model that includes image data from both energies. Furthermore, interpolation can account for the amount of movement (e.g., linearity, rotation, etc.) of the x-ray tube 100 when generating a projection using the first energy and when generating a projection using the second energy. Therefore, a projection about a single pose can be generated using both energies via interpolation that accounts for the movement of the source 100 during image acquisition.

[0048] In addition to generating x-rays from one or more sources at two different energies and / or as an alternative, filter assembly 200 can be used to help ensure or generate a selective difference between the x-ray spectra of two different energies of x-rays. Suitable filter assemblies include those disclosed in U.S. Patent Application Publication 2018 / 0310899 (published November 1, 2018, entitled "FILTER SYSTEM AND METHOD FOR IMAGING A SUBJECT"), which is incorporated herein by reference. Filter assembly 200 can be operated in a selected manner, such as an interval mode that can be timed and / or gated to involve various parameters including those discussed above for image acquisition. Thus, filter assembly 200 can be operated to image patient 14 to achieve a difference between the two energies of x-rays.

[0049] Steering Reference Figure 2 The image shows a filter assembly 200. The filter assembly 200 may include a filter member 210 carried by a filter carrier 210, wherein the filter carrier 210 is rotatable about an axis 214 on an axis 218. The filter member 204 may be formed of a selected material (including those that selectively attenuate X-rays, including lead, aluminum, tin, etc.) and is fixed to the filter carrier 210. The first filter 204 may block or limit selected X-ray photons associated with a selected energy of a broadband beam, as discussed herein.

[0050] The first filter component 204 may be secured or held together with the carrier in a chosen manner (e.g., holes may be formed in the filter component 204, and one or more screws 222 secure the filter component 204 to the filter carrier 210 by passing through or engaging the filter component 204 and the filter carrier 210). It should be understood that other securing mechanisms (such as welding, adhesives, brazing, etc.) may be provided to secure the filter component 204 to the filter carrier 210. The carrier 210 may also be provided as a frame such that X-rays passing through the filter component 204 and reaching the detector 38 pass through the filter component 204 but not through the material of the filter carrier 210.

[0051] like Figure 2 As shown, the filter carrier 210 may have a curved outer edge 226, such that the filter carrier 210 includes a radius 228 and has an arcuate outer edge 226. Therefore, the filter carrier 210 may form at least a portion of a circular or circular member. The combination of the filter carrier 210 and the filter member 204 may have a selected mass, which defines or forms only a portion of the circle. Therefore, a balancing member 230 may be fixed to the filter carrier 210 to balance the mass of the filter member 204 and the filter carrier 210.

[0052] The balancing element may have an arcuate outer edge 234 and a radius 238 substantially similar to that of radius 228. Therefore, the balancing element 230 may form a circle with the filter carrier 210. The balancing element 230 and the filter carrier 210 form a filter carrier assembly 240 to move the filter member 204 relative to the x-ray, thereby positioning it inside or outside the x-ray traveling generally along direction 110, such as... Figure 2 As illustrated in the diagram.

[0053] In various embodiments, the filter carrier 210 may include a second filter element or material 260. The second filter 260 may block or limit selected X-ray photons associated with a selected energy of the broadband beam, as discussed herein. The second filter may be positioned relative to the first filter 204 at a selected location. The second filter 260 may replace or serve as a positioning element for the first filter 204. Thus, the second filter 260 may also be positioned within the beam 110 as the filter carrier 210 rotates.

[0054] The filter carrier 210 is rotatable about an axis 218 having or forming a central axis 214. The filter carrier 210 can be operated to rotate in two directions or in a single direction (such as in the direction of arrow 250 about axis 214). In various embodiments, the filter carrier 210 can be moved to carry the filter member 204 in substantially one rotational direction.

[0055] According to various embodiments, the filter carrier 210 can be operated to rotate about axis 214 at a selected rate. The selected rate can be a substantially constant speed and a rotational speed per minute (RPM) and / or can be varied for a selected time period. Thus, the second filter 260 and / or the selected opening region (e.g., no filter) can be in the beam path 110 regardless of whether the filter component 204 is in the beam path 110. In various embodiments, selected portions of the filter assembly 200 can be placed in the beam 110 every approximately 33 milliseconds.

[0056] In various embodiments, the filter carrier assembly 210 may be connected to a carrier gear 270. In various embodiments, the carrier gear 270 is driven by a belt 274, which is driven by a drive gear 278 connected to a shaft 282 powered by a motor assembly 302. The motor assembly 302 may include a housing 306 and a power motor (not specifically shown) within the housing 306. The motor assembly 302 may be powered by various power mechanisms, such as electric, pneumatic, etc. The motor assembly 306 may be any suitable motor assembly capable of driving the filter carrier assembly 210 at a selected speed and powered by the imaging system 16 and controlled by the controller 32. The motor assembly 306 may include suitable stepper motors and / or servo motors, such as those sold by Maxon MotorAg, which has a business location in Switzerland. EC-I-40 brushless DC servo motor.

[0057] A control connection 314 may be provided and interconnected with the imaging system controller 32. As discussed above, the positioning of the filter assembly 200 may be controlled by the imaging system controller 32 to filter the X-ray spectrum, as discussed above. The filter assembly carrier assembly 210 may be mounted to the carrier gear 270 via a suitable mechanism (such as one or more screws, bolts, adhesives, rivets, or other suitable mechanical or chemical adhesion of the carrier assembly 210 to the carrier gear 270). Thus, when the drive gear 278 rotates, the belt 274 may drive the carrier gear 270 to rotate the filter carrier assembly 210 (including filter components 204, 260) at a selected rotational rate. However, it should be understood that the motor assembly 302 may be directly connected to the carrier gear 270 without the belt 274. In a direct connection, for example, the carrier gear 270 may be directly mounted to the shaft 282 (e.g., instead of the drive gear 278) and / or the carrier gear 270 may directly engage the drive gear 278 without the belt 274 and / or other transmission systems. Alternatively, other suitable drive or transmission mechanisms may be provided between the drive gear 278 and the load-bearing gear 270, such as worm gears, gear drives or other suitable connection systems.

[0058] During operation, the position of filter assembly 200 may be synchronized with the position of beam 110, while emitting X-rays at a selected power, which are intended or selected to pass through filter assemblies 204, 260 before reaching patient 14. According to various embodiments, filter assembly 200 may include an encoder assembly. The encoder assembly may be used to sense, determine, and / or transmit the position of filter carrier 210 to controller 32 or other suitable controller. In various embodiments, the encoder may include various components, such as a magnetic member 320 positioned on carrier 210 and a sensor (e.g., a Hall effect sensor) 324 positioned to sense movement of the magnetic member 320. The encoder may include those disclosed in U.S. Patent Application Publication 2018 / 0310899 (published November 1, 2018, entitled "FILTERSYSTEM AND METHOD FOR IMAGING A SUBJECT"), which is incorporated herein by reference.

[0059] Continue to refer to Figure 2 Referring also to Figure 3, the imaging system 16 can be used to generate a projection of the patient 14 at detector 38 using one or more energies. Specifically, the energy of the beam (such as an X-ray beam traveling along the path of ray 110) can be discrete, and the selected energy strikes or reaches detector 38 and / or patient 14. For example, a beam traveling along path 110 through patient 14 to detector 38 can be selected to be at least two different energies. As discussed herein, these two energies can be separated by a selected amount.

[0060] In various embodiments, for example, the source 36 at the x-ray tube 100 may deliver or emit a broadband beam (such as an x-ray beam) having a number of different energy levels encompassing a broad energy spectrum. For example, the beam emitted by tube 100 may emit beam 110a in the direction of ray 110 to encompass an energy spectrum (e.g., from about 40 keV to about 140 keV), wherein peak energies include from about 50 kVp to about 200 kVp, and from about 80 kVp to about 140 kVp. However, at each of these peak energies, it should be understood that the energy range in the spectrum may include the peak. However, beam 110a may be selectively modified and / or filtered.

[0061] like Figure 2As schematically shown, beam 110a is emitted from tube 100. When the beam passes through filter assembly 200, it may engage a first filter 204 and / or a second filter 260. Therefore, beam 110a can be attenuated by both filters 204, 260. In various embodiments, the two filters may limit or attenuate beam 110a to two different energies in a filtered beam portion 110b. Thus, beam 110a may include a pre-filter portion 110a and a second filtered portion or a post-filter portion 110b. The post-filter portion 110b may have two different energies depending on which filter it passes through.

[0062] like Figure 3A and Figure 3B As schematically shown, the pre-filter beam 110a can be a broadband beam and can have a selected energy range or spectrum, as discussed above. The post-filter beam 110b passing through the first filter 204 can have a first beam spectrum in which low-energy X-rays are attenuated and thus the half-value layer (HVL) is increased, which can also change the kVp of the post-filter beam. (Reference) Figure 3A The first filter 204 can filter the pre-filtered beam portion 110a into a first selected filtered spectrum 110b', which may also be referred to as a partial or limited beam.

[0063] Steering Reference Figure 3B The second filter 260 can filter the broadband pre-filtered beam 110a into a second selected post-filtered beam 110b. The second post-filtered beam 110b may include selected power characteristics (such as a spectrum or voltage that is separate from or different from the first post-filtered beam 110b') and may also have a different HVL. The second post-filtered beam energy 110b (which may also be referred to as a finite beam or partial beam) may have a second post-beam spectrum with an HVL higher than that of the first post-filtered beam.

[0064] Therefore, the first and second filtered beams can have different peak energies (e.g., a difference of about 40 kVp to about 80 kVp), with each beam selected from a range of about 40 kVp to about 200 kVp. However, each selected kVp can have a known or understood range around that kVp. Furthermore, the HVL can differ between the first and second filtered beams. For example, the HVL can differ from about 2 mm of aluminum (mm Al) to about 8 mm Al, and the HVL value for each beam can be selected from about 1 mm Al to about 15 mm Al, including about 2 mm Al to about 10 mm Al. Those skilled in the art will understand that HVL is the equivalent thickness of aluminum (Al) that reduces the beam intensity by half.

[0065] like Figure 3A and Figure 3B As shown, the filter carrier 210 may also define one or more openings or channels 210a. For image acquisition and / or other purposes, the openings may allow unfiltered or broadband beams to pass through. Thus, one or more filter arrangements and / or openings can be used to acquire image data (i.e., broadband beam image data acquisition).

[0066] like Figure 3A and Figure 3B As shown, both filtered beams 110b can reach detector 38. However, in both cases, the filtered beam 110b can pass through subject 14 and / or be attenuated by the subject. Therefore, since both filtered beams 110b' and 110b'' include different energy or power characteristics attenuated by patient 14 and reaching detector 38, the projection received or determined using detector 38 can be based on different beam energies. Thus, although a single pre-filtered beam 110a can be emitted by source 36 including x-ray tube 100, the attenuated or reaching subject 14 beam can be distinguished into at least two different beams. The two different energies of the two different filtered beams 110b' and 110b''' can be used to distinguish and / or differentiate various features in patient 14 in the image data collected at detector 38 as discussed above. However, a single source tube and a single pre-filter beam 110a can be used to generate two post-filter beams 110b', 110b' with different energies. A filter assembly 200 including two filter components 204, 260 can be used to generate two different post-filter beams 110b', 110b'. However, it should also be understood that the filter assembly may include more than two filters and / or opening regions, which allow the generation of more than two energies and / or allow the entire broadband beam to pass through path 110 for image data acquisition.

[0067] Therefore, the image acquisition or image data acquisition of subject 14 at detector 38 can be selected in a manner (such as according to...) Figure 4 The method shown is 300. Method 300 can be used to acquire image projections or image data of subject 14 under two different energy or power characteristics, namely a beam 110a from a single source tube 100 and a single broadband beam 110a. The method may begin in box 310, which may include positioning subject 14 relative to imaging system 16, moving imaging system 16 relative to subject, or other suitable procedures.

[0068] Method 300 can be used to collect image data of subject 14 using either a first filtered beam 110b' or a second filtered beam 110b'. However, it should be understood that additional filters may be provided, and thus additional or more than two filtered beams with different and distinguishable energies may also be generated. Furthermore, although the methods herein illustrate and reference the use of two filters 204, 260, it should be understood that for the operation of imaging system 16, only a single filter may be used to collect all projections of subject 14 and / or only two filters may be selected from a plurality of filters. Therefore, the discussion herein using two filters 204, 260 is merely exemplary in the inclusion of multiple filters to achieve multiple filtered beam energies for collecting multiple image data of subject 14.

[0069] Therefore, after starting in box 310, method 300 may include selecting a location in box 314 for the projection of the first energy image. For example, the image assembly 16 may include rotation of the source 36 relative to the subject 14 and / or other movement of the gantry 34 relative to the subject 14. As discussed above, the gantry 34 may be axially movable along the long axis 14L of the subject 14 in the direction of arrow 44, rotated in the direction of arrow 40, and moved perpendicular to and / or orthogonally to the long axis 14L in the direction of arrow 42. Therefore, selecting a location in box 314 for the projection of the first energy image may include positioning the source 36 relative to the subject 14 in any suitable location. For example, it may be desirable to acquire image data for imaging and / or reconstructing a model of a selected portion of the subject, such as a selected vertebra. Therefore, those skilled in the art will understand that positioning the imaging system to acquire the first energy projection may include positioning the imaging system 16 relative to the subject 14 to acquire the selected image.

[0070] After a selection is made in box 314, the first filter can be moved into the broadband beam in box 318. As discussed above, the first filter 204 can be moved into beam path 110 to produce a first filtered beam 110b'. Therefore, image data can be collected using the first filtered beam in box 322. After collecting the first image data using the first filtered beam in box 322, a location for projecting the second energy image can be selected in box 326. As discussed above, collecting the second energy image is not required; however, if collecting the second energy is selected, the location can be determined in box 326. This location can be a selected location made in a manner similar to that discussed above regarding the selection of the first energy projection in box 314. In various embodiments, for example, a projection at the subject 14 can be selected, such that neither energy nor, consequently, movement of the imaging system (such as source 36 including x-ray tube 100) occurs. However, it should be understood that the source 36 is movable, such as rotating around the subject 14 and / or rotating due to the movement of the platform 34 relative to the subject.

[0071] After selecting the location for the second energy projection in box 326, the second filter 260 can be moved into beam 110a in box 330. After the filter is moved into beam 110a, the second filtered beam 110b” can pass through the filter assembly 200 to collect image data when the second filtered beam in box 334 is available. Therefore, by moving the individual filters 204, 260 into beam 110a, image data can be collected using filtered beams 110b', 110b” at two energies. A single broadband beam 110a can be filtered to generate or create any one and / or both of filtered beams 110b', 110b”. Filtered beams 110b can also be referred to as partial or finite-spectral beams because they are finite or partial spectra of the broadband beam 110a.

[0072] After collecting the second filtered beam image data in box 334, a determination can be made in box 338 as to whether additional projection is required. If no additional projection is required or not selected, the “No” path 342 can be followed to the ending box 346. The ending in box 346 may include ending or collecting projection using either the filtered beams 110b' and 110b”. However, it should be understood that other procedures may occur (such as reconstruction of the selected model, performing procedures on subject 14), or other appropriate post-imaging procedures may occur.

[0073] If a different projection is selected in box 338, the "Yes" path 350 can be followed. The "Yes" path 350 allows selection of either or both of the image projections having the first or second filtered beam. As discussed above, the filter assembly 200 may also include an opening or blank area 210a in the filter carrier. Therefore, if selected, a full-spectrum or broadband beam 110a can also be used to collect image data. Therefore, it should be understood that a broadband image can also be collected at box 351. However, it should be understood that a broadband image is optional.

[0074] After determining and / or collecting optional broadband image data, the first filtered beam path 354 can be followed to select the location of the first energy image projection in box 314 to continue or cycle the process. Therefore, only the first energy image projection can be collected and / or both the first and second energy projections can be collected.

[0075] However, in addition to and / or as an alternative, a second filtered beam path 358 may also be followed. The second filtered beam path 358 may be moved to the position selected in box 326 for second energy image projection. Again, as discussed above, image data may be collected at any one or both of the first or second energy and / or other additional energies, and / or it may not be necessary to collect image data at all selected energies. Therefore, the "yes" path 350 may include image collection at any selected energy and / or broadband energy, as shown above.

[0076] Imaging system 16, including a single X-ray beam source 100, can emit a broadband beam 110a. Selected filters (such as a first filter 204 and a second filter 260) can filter the single broadband beam 110a into two filtered or partial spectral beams 110b', 110b'". The two filtered beams 110b', 110b'' may include energies that allow the collection of two different energy image projections for a selected purpose (such as for distinguishing a selected contrast agent, selected tissue, or other suitable substance with distinguishable attenuation characteristics). However, imaging system 16 may include a filter assembly 200 to allow the generation of two energy beams, even if the X-ray source tube 100 of source 36 emits only a single broadband initial or primary beam.

[0077] As discussed above, imaging system 16 can be used to acquire image data of subject 14 for the reconstruction of its model. Reconstructing the model of subject 14 may include generating a 3D model of subject 14 using multiple projections acquired using imaging system 16. Therefore, image data acquired relative to subject 14 at multiple locations and / or over a period of time can be used to reconstruct a model (such as model 18 for display on display device 20). Reconstruction can occur as discussed above. However, in various embodiments, reconstruction of model 18 for display may be based on various types of image data acquired from subject 14. As discussed above, dual-energy image data of subject 14 may be acquired. In addition to and / or as an alternative, low-dose or lower-dose image acquisition techniques may be used to acquire image data of subject 14 for performing 3D reconstruction. In various embodiments, for example, source 36 may be positioned at various locations relative to subject 14, and image projections may be acquired at different locations for reconstruction. Therefore, reconstruction is based on multiple projections. In various embodiments, each of the projections may be at a single dose or a selected dose, such as having a different energy spectrum. Therefore, instead of acquiring all image data with a broad spectrum, the X-ray dose to subject 14 can be limited to about 10% to about 60%.

[0078] Acquiring image data of the subject for reconstructing a three-dimensional image may, for example, involve collecting projections around the subject at selected intervals. (Reference) Figure 5 The image system 16 is schematically shown. The image system 16 may include a source 36' that is movable within and / or relative to the gantry 34. It should be understood that the detector 38 may also be movable relative to the source 36 to acquire an image projection of the subject 14. Therefore, although... Figure 5 The stage 34 and source 36' are shown schematically, but it should be understood that the detector and other components of the imaging system 16 may also be present. However, the source 36' may move together with the imaging system 16 around a circle or in another suitable shape relative to the subject 14. Figure 5 As shown, for example, source 36' can be moved to various selected locations, any number of locations can be selected, and the eight locations shown are merely exemplary. However, it should be understood that source 36' can be moved to any appropriate number of locations to obtain the projection of subject 14, thereby ensuring sufficient data collection for performing image reconstruction.

[0079] In various implementations, for example, the imaging system 16 may be operated by a controller 32 based on input from the user 12 or other appropriate input, to... Figure 5Source 26 is moved relative to subject 14 in one of the eight exemplary locations (or other suitable locations) shown. At each location, source 26 may emit high-power or selected-power X-rays, which are detected at a detector used to acquire an image projection of subject 14. The image projection may allow reconstruction of selected images (such as a 3D model) of subject 14.

[0080] However, in various embodiments, the eight locations of source 36 can be used to collect the projection of subject 14 at different or varying intensities of the X-ray beam. In various embodiments, filter assembly 200 can be used in source 36 to vary the power of the beam emitted by X-ray tube 100 passing through subject 14. In various embodiments, for example, reference Figure 6A and Figure 6B Source assembly 36' may include a filter assembly 200' similar to the filter assembly 200 discussed above. Filter assembly 200' may include a first filter 204 and an opening or unfiltered portion 400. The opening portion 400 may be an opening or gap in the filter carrier 210. As discussed above, the X-ray tube or tube 100 may emit a pre-filtered beam 110a. The pre-filtered beam may be filtered by the first filter 204 into a filtered beam 110b. The first filter 604 may filter the pre-filtered beam 110a into a low-energy post-filtered beam 110b.

[0081] Steering Reference Figure 6A The filter assembly 200' is rotatable or movable relative to the filter carrier 210, such that the filter 204 is moved out of the beam 110a and the gap 400 is moved into the beam 110a. Therefore, the source assembly 26'a may include the gap 400 positioned within the beam 110a. Thus, in this position or configuration, the source assembly 36'a can be used to emit a full-power beam such that the beam has the same power after passing through the filter carrier 210 and is unfiltered. Therefore, the full-power beam emitted by the tube 100 can pass through or interact with the subject 14 and be detected at the detector 38.

[0082] Return to reference Figure 5 And continue to refer to Figure 6A and Figure 6B The imaging system 16 can acquire image projections of the subject 14 at different positions relative to the subject 14 with different power or different attenuation. For example, as Figure 6AAs shown, source assembly 36 can be configured as source assembly 36' such that filter 204 is positioned within beam 110a to filter or reduce beam power as the beam passes through or interacts with subject 14. At the location of source 36'a, source assembly 36'a may include an unfiltered beam and is therefore configured to allow an unfiltered beam to pass through source tube 100 and interact with subject 14. Figure 5 As shown, the source assembly 36 can be configured to alternate or alternate between a high-power beam and a low-power beam reaching the subject 14. Figure 5 As shown, the imaging system 16 allows the single source tube 100 to easily change the power of the X-rays reaching the subject 14.

[0083] The imaging system 16 having source assembly 36 can be configured in at least two configurations, including such as Figure 6A The configuration shown is 36' and as follows Figure 6B The configuration 36'a is shown. The x-ray tube 100 can emit a beam 110a. In the first or filtered configuration, a first filter 204 can filter the beam 110a, such that the source assembly 36 emits a filtered beam 110b. The filtered beam 110b can be a low-power beam and / or a different spectrum reaching the subject 14. The low-power beam 110b can include selected power characteristics (such as kVp and beam filtering amount).

[0084] The source assembly 36'a configuration may include the filter carrier 210 and / or the unfiltered area 400 of the filter assembly 200, such that the emitted beam 110a is emitted from or exits the source assembly 36'a and reaches the subject 14 at full power or a first power. Therefore, the source assembly 36'a allows the emission of a high-power radio beam to reach the subject 14.

[0085] Therefore, as shown above, a single source assembly 36, including a single source tube 100, can be used to emit a beam at high power or a first power 110a and a second power or a low power 110b. Figure 5 As shown, the source assembly 36 can be changed between configurations of alternating positions, or to acquire alternating frames of image projections of the subject 14. Therefore, the imaging system 16 can be used to acquire image projections of the subject 14 at two different frequencies from different positions.

[0086] The low-power beam 110b allows for the acquisition of image projections of the subject 14 at a lower power compared to the high-power full-power beam 110a. Therefore, when the alternating source assembly 36 is configured, as... Figure 5 As shown, a lower dose can be used to acquire a selected set of image projections of subject 14 compared to acquiring all projections at a higher full dose. Figure 5As exemplarily illustrated, a complete set of projections of subject 14 can be acquired by selecting a power reduction. Therefore, instead of acquiring all image data with a broad spectrum, the X-ray dose to subject 14 can be limited to approximately 10% to approximately 60%.

[0087] Due to such Figure 5 The low-power acquisition at position 36' shown allows for a total lower dose (e.g., X-ray) of the selected projection for reconstruction onto subject 14. High-dose projection 36'a allows for a high signal-to-noise ratio (SNR) in the model used to reconstruct subject 14. Low-power projection may have a lower SNR but provides appropriate data to aid in the reconstruction of model 18 of subject 14. For example, low-power projection may allow for the identification of edges of various features of subject 14, such as bone or high-attenuation structures. Therefore, while a high SNR may not be achievable using low-power projection, selected information can be acquired to aid reconstruction. Interpolation can be performed between high-power and low-power projections to aid reconstruction. Thus, reconstruction can be performed using low-power projection even if a lower SNR is achievable.

[0088] Various reconstruction techniques can be used to construct model 18 of subject 14, even when projecting from images with a low signal-to-noise ratio. Low signal-to-noise ratio projections can also be referred to as noisy projections, even if they include the selected data.

[0089] To perform reconstruction, various reconstruction techniques may include, for example, machine learning systems. Machine learning systems can be trained to identify features in high-noise projections to help define the reconstruction using sparse data collection techniques that include selected or alternating high-energy or high-dose projections. Low-dose projections may allow or generate sparse image acquisition or data acquisition for subject 14, where the selected reconstruction technique can be used to textualize the sparse data (such as identifying edges within the low-dose projection). High-dose projections can be used to identify spatial resolution and perform reconstruction, and low-loss reconstruction can be provided in conjunction with high-noise projections used for interpolation or to aid the reconstruction method. Therefore, instead of acquiring all image data with a broad spectrum, the X-ray dose to subject 14 can be limited to approximately 10% to approximately 60%.

[0090] In various embodiments, as discussed above, the imaging system 16 including the filter assembly 200 may include additional or alternative filter components (such as those included in...). Figure 7(Those in the filter system 500 shown). The filter system 200 may include a filter carrier 210' similar to the filter carrier 210 discussed above. The filter carrier 210' may be driven by various assemblies and portions, including those discussed above (such as those that can be directly driven and / or via various driven motors or motor assemblies 302 discussed above). However, the filter carrier 210 may rotate relative to the source 36 and the detector 38. The source 36 may emit a beam along the beam path 110. The beam emitted by the source 36 may pass through a portion of the filter carrier 210 and reach and / or be blocked or filtered by the filter portions on the filter carrier 210.

[0091] In various embodiments, the filter carrier may carry or move one or more filter portions. The filter carrier 210 may hold a first filter portion 510, a second filter portion 514, a third filter portion 518, and a fourth filter portion 522. Each of the filter portions may be similar to one another but includes varying sections, as further discussed herein, that may block a portion or area of ​​the beam 110. In various embodiments, for example, each of the filter portions 510, 514, 518, 522 may be provided to aid in detecting and / or correcting scattering of the beam 110 between the source 36 and the detector 38. The beam 110 may be an X-ray beam emitted by a tube (such as tube 100) and the source 36. The X-ray beam may pass through or relative to the filter carrier 210 to reach the detector 38 and be detected to generate an image projection of a subject (such as subject 14). However, the beam 110a may be scattered by various interactions, including interactions with air or other materials.

[0092] Each of the filter segments 510-522 may include a different or selected configuration. For example, the filter segment in 510 may include a filtering or blocking portion 530 and an opening or blanking portion 534. The blocking portion 530 may include a portion that substantially or completely blocks the beam 110a from passing through the filter segment 510 toward the detector 38. The blocking portion 530 may, for example, include a high-density X-ray blocking material (such as lead) or other suitable material. The blanking portion 534 may be substantially open, such as an air gap or opening positioned relative to the blocking portion 530. The filter segment 510 may include selected dimensions, such as a first dimension 538 and a second dimension 542. For each segment or portion where the projection of the subject 14 can be acquired at the detector 38, dimensions 538, 542 may generally be known or consistent. Thus, the filter carrier 210' may also be formed of a substantially blocking material such that the beam 110a passes substantially only through the filter portion (including the blanking portion 534 of the filter portion 510).

[0093] As discussed above, the filter carrier 210 may include a selected number (e.g., four) of filter regions, including filter region 510, filter region 514, filter region 518, and filter region 522. Each of the filter regions may include substantially blocking portions, such as blocking portions 550, 554, and 558 of the respective filter regions 514, 518, and 522. Each of the filter regions may also include corresponding void or opening portions 560, 564, and 568 of the respective filter regions 514, 518, and 522. Thus, each of the filter regions may include substantially blocking regions 530, 550, 554, and 558 and corresponding opening or void regions 534, 560, 564, and 568.

[0094] Each of the filter regions 510, 514, 518, and 522 can be positioned relative to the beam 110. For example... Figure 7 As shown, the corresponding gap portions and blocking portions positioned within the beam 110 can allow the beam to be defined or allow the beam to pass through blocking portions different from the gap portions to identify or block selected halves, thereby allowing the quadrant of detector 38 to be defined. Figure 7 As shown, when the filter carrier 210 rotates about the center point 570 in a selected direction (e.g., approximately along direction 574), each of the filter regions 510, 514, 518, and 522 passes through the beam 110. Each of the filter regions, including the blocking portion, allows blocking half of the detector space or surface. Therefore, a quadrant can be defined on the detector 38 when each of the four blocking regions or filter regions passes through the beam 110. The blocking regions, positioned relative to the opening or gap area, allow imaging or definition of the scattered portion of the beam 110.

[0095] Continue to refer to Figure 7 And refer to other sources Figure 8 The image shows filter region 510 as an example. As discussed above, filter region 510 includes a gap portion 534 and a blocking portion 530. Source 36 can emit beam 110 through filter region 510 and toward detector 38. Figure 8 As shown, the blocking region 530 blocks a portion of the beam 110 (such as substantially about half of the beam 110, including the blocked beam portion 110x). The opening or blade portion 534 allows the beam 110 to pass through, and allows the unblocked beam portion 110y to pass through.

[0096] like Figure 8As shown, the beam 110 may be separated or at least partially separated between the blocked portion 110x and the through or passing portion 110y. The through portion 110y (also referred to as the partial beam) may contact the detector 38 to generate or allow the generation of a projection through the portion 110y. However, the blocked portion 110x is generally blocked and cannot reach the detector 38. Figure 8 As shown, the filter region 510, including the through or gap portion 534 and the blocking filter 530, allows the beam 110 to be separated into a blocked portion 110x and a through portion 110y. As discussed above, the filter carrier 210 may include a selected number of portions (such as four filter gap regions or portions 510, 514, 518, 522) to allow the generation or selection of different blocked portions of the beam 110, and as... Figure 8 The blocking portion or filter portion 510 shown is merely exemplary.

[0097] Filter region 510 (including other filter regions as discussed above, including blocking portion 530) typically blocks at least a portion of detector 38 from the influence of beam 110. However, beam 110 may have a certain amount of scattering due to various interactions of portions of beam 110, interactions with beam 110, or the portions it reaches, or other factors. Therefore, in various embodiments or under various conditions, beam 110 may have scattering such that all rays (e.g., X-rays in beam 110) do not travel in a straight path from source 36 to detector 38. Scattering can be detected and / or determined as discussed herein.

[0098] like Figure 8 As shown, for example, the beam or a portion of the beam passing through the gap region 534 may be scattered due to various interactions along the direct or straight path from source 36 to detector 38. A portion of the beam 110 that travels substantially straight through source 36 to detector 38 may typically pass along the unobstructed beam 110y or within its region. The portion of the beam passing through the gap region 534 may be scattered for various reasons. Therefore, as... Figure 8As shown, exemplary scattered portions of the beam may include scattered portions 110za, 110zb, and 110zc. One or more scattered portions 110za, 110zb, and 110zc may contact detector 38 in a normally blocked area or region 38x, which may also be referred to as a blocked portion or region. The blocked region 38x may typically be a region of detector 38 that is blocked by the blocking region 530 of the filter region or portion 510. Therefore, any detection in the blocked region 38 is typically due to the scattering of 110za, 110zb, and 110zc by the beam 110. Scattered beam portions 110za, 110zb, and 110zc may interact with or reach detector 38 in the blocked region 38x. It should be understood that different locations of the blocking portions (such as blocking portion 530, which includes blocking portions 550, 554, and 558, as discussed above) may create or allow the determination of different scattering regions or portions.

[0099] Continue to refer to Figure 8 And refer to Figure 9 The scattered beam information (i.e., the detected portion on detector 38 in the blocked region 38x) can be used to selectively determine and / or correct scattering distortion and / or artifacts in the image data. Reference Figure 9 The image data or projection 570 is shown. The imaged projection 570 may include an unobstructed or beam-projected portion 11Oy'. An obstructed or non-image-projected portion 11Oz' may also be included in the image data 570. Figure 9 As schematically illustrated, the projection 570 of the image may include an unobstructed region 110y′, which substantially encompasses the entire region of the detector 38 irradiated by the beam 110. As discussed above, a gap region 534 may allow the beam 110 to pass through and reach the detector 38 in region 110y.

[0100] However, because detector 38 is blocked by obstruction region 530, the projection at 570 will typically include gaps or unprojected areas. However, as discussed above, scattering allows for partial scattering of the beam 110z1, 110z2, 110z3. The scattered portion of the beam 110z1 can produce a selected detection on detector 38, which can be detected for use in the projection or image data 570. Figure 9 As exemplarily shown, the blocked portion may also include scattered projection data 110za', 110zb', and 110zc'. It should be understood that any appropriate or dispersed amount of data can be detected at detector 38 within the blocked area. Therefore, projection 570 may include more than three scattering points, such as... Figure 9 As shown, the more than three scattering points are almost all included in the examples discussed in this paper.

[0101] As discussed above, the projection 570 obtained using one of the selected filter regions can be used to correct the image data collected using the imaging system 16. As discussed above, various projection or blocking regions can be used to determine any appropriate division of the detector 38 for scattering image data or artifacts. The inclusion of four projection regions or filter regions is merely exemplary. However, each of the filter regions allows for the determination of a selected amount of scattering relative to the detector 38 and the source 36.

[0102] like Figure 9 As exemplarily illustrated, the projected image 570 may include scattered image data. The scattered image data 110z' can be used to correct image data collected using the imaging system. For example, any filter applied to the imaging system 16 (even including lower or partial filtering filters) may allow or include scattered image data. Therefore, a scattered filter including the scattered filter regions 510-522 as discussed above may allow the collection of scattered projections (including...) Figure 9 (Shown as a scattering projection of scattering image 570). The scattering image can be acquired using imaging system 16. The scattering image can then be subtracted from a selected projection to allow for correction of the scattering data and image projection. For example, as... Figure 9 As shown, the scattering projection points 110z1', 110z2', and 110z3' can be subtracted from the selected image projection acquired using the imaging system 16. When the imaging system 16 collects the image projection of the subject 14, the scattering data can be subtracted to allow for the reduction of artifacts caused by scattering. Additionally, the occluded portion 38x of the image acquisition area 110z1 can be allowed to change over time. That is, during image data acquisition (i.e., projection acquisition), the filter can move over time to occlude different portions of the detector 38. Therefore, the occluded area or portion can change or be altered with each acquisition, and each acquisition can change over time due to the movement of the imaging system 16 and / or the filter portion 510. Therefore, the position of the occluded portion generated by the filter member 510 can change over time with and relative to the acquisition time.

[0103] Therefore, the imaging system 16 may include one or more filter sections that allow filtering and selection of selected image projections collected by the imaging system 16. Due to the interaction of the X-ray beam from source 36 with its physical properties and / or the interaction of the projection or the environment through which the beam passes, the filter sections may generate scattered image data or projections. Scattering filters (such as filter sections 510-522) may be moved into the beam 110 to aid in and / or determine the scattering of the beam 110 in the imaging system 16. Thus, scattering filters or sections 510-522 may help determine or correct the scattering as discussed above.

[0104] The foregoing description of embodiments has been provided for illustrative and descriptive purposes. The foregoing description is not intended to be exhaustive or limiting of the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable and may also be used in selected embodiments where applicable, even if not specifically shown or described. The same element or feature may be varied in many ways. Such variations are not considered to depart from the invention, and all such modifications are intended to be included within the scope of the invention.

[0105] It should be understood that the various aspects disclosed herein can be combined in combinations different from those specifically given in the specification and drawings. It should also be understood that, depending on the example, certain actions or events of any of the processes or methods described herein may be performed in a different order, or may be completely added, combined, or omitted (e.g., performing these techniques may not require all the described actions or events). Furthermore, although for clarity some aspects of this disclosure are described as being performed by a single module or unit, it should be understood that the techniques of this disclosure can be performed by combinations of units or modules associated with, for example, a medical device.

[0106] In one or more examples, the described techniques may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functionality may be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include non-transitory computer-readable media, which correspond to tangible media such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and is accessible by a computer).

[0107] The instructions can be executed by one or more processors, such as one or more digital signal processors (DSPs), general-purpose microprocessors, graphics processing units (GPUs), application-specific integrated circuits (ASICs), field-programmable arrays (FPGAs), or other equivalent integrated or discrete logic circuit systems. Therefore, the term "processor" as used herein can refer to any of the foregoing structures or any other physical structures suitable for implementing the described techniques. Furthermore, this technique can be fully implemented in one or more circuit or logic elements.

Claims

1. An imaging system configured to acquire an image projection of a subject, the imaging system comprising: The source is configured to emit X-rays as a whole beam having the entire cross-sectional area; Filter assembly, the filter assembly comprising: A filter component configured to block at least a portion of the cross-sectional region of the entire beam to form a partial beam. A filter carrier is configured to move the filter member relative to the entire beam such that the filter member blocks at least a portion of the entire beam to form the partial beam, and to move the filter member away from the entire beam to allow the entire beam to pass through; Detector, the detector being configured to detect the X-rays in the entire beam and the portion of the beam; and A control system configured to control the position of the filter element using the filter carrier to detect the entire beam and the portion of the beam; The calibration system is configured to execute instructions to: Determine the scattering of X-rays in the partial beam at least at the detector, and Determine projection correction to correct the scattering of the X-rays; The filter component includes a first filter component and a second filter component; The first filter component blocks a first portion of the entire beam to form a first partial beam, and the second filter component blocks a second portion of the entire beam to form a second partial beam. The first portion of the beam is detected at the detector to determine a first scattering in a first detector region, and the second portion of the beam is detected at the detector to determine a second scattering in a second detector region; The filter component further includes a third filter component and a fourth filter component; The third filter component blocks a third portion of the entire beam to form a third portion beam, and the fourth filter component blocks a fourth portion of the entire beam to form a fourth portion beam. The third portion of the beam is detected at the detector to determine the third scattering in the third detector region, and the fourth portion of the beam is detected at the detector to determine the fourth scattering in the fourth detector region; The first detector region, the second detector region, the third detector region, and the fourth detector region are configured to overlap to allow for the determination of scattering in the four quadrants of the detector.

2. The system according to claim 1, further comprising: A reconstruction system configured to reconstruct a model of the subject using image data acquired using the entire beam, based on a determined projection correction.

3. The system according to claim 1, The filter carrier further defines an opening channel to allow the entire beam to pass through and be detected at the detector.

4. A method for correcting X-ray scattering, the method using the imaging system of claim 1, comprising: The entire beam of X-rays is emitted from a source having the entire cross-sectional area; The entire beam is detected at the detector; The entire beam is selectively blocked using a filter component to block at least a portion of the cross-sectional area of ​​the entire beam to form a partial beam; The portion of the beam is detected at the detector; as well as Operate the processor module to execute instructions that are operable to: Determine the scattering of X-rays in the partial beam at least at the detector, and Determine projection correction to correct the scattering of the X-rays.

5. The method according to claim 4, further comprising: When the first portion of the beam is detected, the scattering of X-rays in the blocked area of ​​the detector, excluding the first detector area, is detected; Operating the processor module to execute instructions to determine the scattering of the x-rays includes receiving x-ray scattering image data.

6. The method of claim 5, wherein operating the processor module to execute instructions to determine projection correction operable to correct the scattering of the x-rays comprises: Remove scattered X-ray image data from image data based on projections obtained using the entire beam.

7. The method according to claim 6, further comprising: A reconstruction is generated based on the determined projection correction.

8. A method for correcting X-ray scattering in image reconstruction, the method using the imaging system of claim 1, comprising: The entire beam of X-rays is detected at the detector, which detects multiple entire projections. Based on a partial beam of X-rays, multiple partial projections are detected at the detector, wherein the partial beam is a portion of the entire beam that is blocked by a filter element; Multiple scattered X-ray projections are detected at the blocked portion of the detector, wherein the blocked portion is the portion of the detector configured to be blocked by the filter member; as well as The processor module is operated to execute instructions that are operable to determine projection corrections in the plurality of overall projections to correct the scattering of the X-rays in the detected plurality of scattered X-ray projections.

9. The method according to claim 8, further comprising: The partial beam is formed by selectively blocking the entire beam with the filter component to block at least a portion of the cross-sectional area of ​​the entire beam.

10. The method of claim 9, wherein detecting the plurality of scattered X-ray projections at the obstructed portion of the detector comprises: Acquire image data at the selected acquisition time; The position of the obscured portion created by the filter component changes over time as the acquisition time increases.

Images