Fast vibration correction for images with metal objects in CBCT

Abstract

The present invention relates to vibration correction. A vibration artifact suppression method 100 includes: a) step 110 of reconstructing a three-dimensional image of an object of interest based on projection data acquired by an X-ray imaging system; b) step 120 of determining whether the reconstructed three-dimensional image includes a metal object; and c) step 130 of performing a vibration correction method based on a metal object segmented in the reconstructed three-dimensional image in response to the determination that the reconstructed three-dimensional image includes a metal object; or c2) step 140 of performing a vibration correction method based on an object of interest segmented in the reconstructed three-dimensional image in response to the determination that the reconstructed three-dimensional image does not include a metal object. Using the vibration artifact suppression method, the number of iterations is significantly reduced, resulting in a significant speedup of the overall reconstruction time.

Description

[Technical Field]

[0001] The present invention relates to a vibration artifact suppression method, a vibration artifact suppression device, an X-ray imaging system, a computer program product, and a computer-readable medium. [Background technology]

[0002] Three-dimensional (3D) imaging with interventional C-arm systems is an area of ​​increasing interest for many interventional procedures. For data collection, motorized movement of the C-arc is performed to move the tube and detector around the region of interest. During this movement, projection data is acquired that can be used with knowledge of the tube and detector positions to reconstruct a 3D image.

[0003] In the geometry data obtained from the calibration procedure, it can be observed that the C-arc oscillates during acquisition due to acceleration forces associated with the movement. If the phase and / or amplitude of the oscillation pattern deviates between the calibration procedure and the interventional data acquisition, significant image artifacts can occur that significantly impair image quality. This can particularly affect moving C-arm systems, as the vibrations are significantly greater than in fixed systems. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, there may be a need for improved vibration compensation for x-ray imaging systems, such as, for example, moving C-arm systems. [Means for solving the problem]

[0005] The object of the present invention is solved by the subject matter of the independent claims, further embodiments are incorporated in the dependent claims.

[0006] In a first aspect, a vibration artifact suppression method is provided, the method comprising: a) reconstructing a three-dimensional image of an object of interest based on projection data acquired with an X-ray imaging system; b) determining whether the reconstructed three-dimensional image contains a metal object; c) performing a vibration correction method based on the segmented structure of interest in the reconstructed three-dimensional image; and the structure of interest is selected based on the result of the determining step.

[0007] In other words, the present disclosure proposes a vibration compensation method for an X-ray system, such as a moving C-arm system, to effectively reduce vibration artifacts.

[0008] In a particular example, the vibration artifact suppression method disclosed herein includes an initial reconstruction in which certain reconstructed image structures are segmented. The segmented image structures are forward projected onto the originally acquired projections and aligned with corresponding structures in the projection data to estimate vibration. Using the estimated vibration information thus determined, a new reconstruction with reduced vibration artifacts can be performed. If necessary, the process may be repeated multiple times to obtain sufficient image quality.

[0009] The image structures to be segmented are selected based on the result of determining the presence of metal objects. That is, in some cases where the reconstructed image contains metal objects, the image structures to be segmented include the metal objects, and step c) includes c1) performing a vibration correction method based on the segmented metal objects. In this case, advantageously, the number of iterations can be small, even for mobile C-arm 3D imaging. This is explained in detail below, particularly for the image shown in FIG. 4. Thus, if one or more metal objects are present, the one or more metal objects are segmented and used as a basis for vibration estimation.

[0010] In other cases where the reconstructed image does not contain metal objects or where a limited amount of metal is present, for example, bone structures are segmented instead of the metal and used as a reference for vibration estimation, i.e., step c) includes c2) performing a vibration correction method based on the segmented bone structures.

[0011] This is explained in more detail below, particularly for the example shown in FIG.

[0012] In one embodiment, step c1) further includes determining an amount of metal objects in the reconstructed three-dimensional image, and determining based on the amount of metal objects whether to perform a vibration correction method based on the metal objects segmented in the reconstructed three-dimensional image.

[0013] Apart from simply determining whether an image contains metal, it is optional to check whether enough metal structure is available to robustly estimate vibration. This may be done by checking how many image slices have a significant portion of metal structure. Since the distribution within the field of view (FOV) is an important aspect for robust vibration correction, other possible criteria could be the metal volume percentage or the metal convex hull volume percentage.

[0014] In one embodiment, the amount of metal objects is: the number of image slices in the projection data that have metal objects; Volume percentage of metal objects, or The volume percentage of the convex hull of the metal object, The determination is based on at least one of the following:

[0015] In one embodiment, a vibration correction method comprises: Segmenting metal objects in the reconstructed three-dimensional image; forward projecting the segmented metal object onto the acquired projections of the projection data; aligning the forward projected metal object with the metal object in the acquired projections to estimate vibrations of the C-arm X-ray imaging system during acquisition of the projection data; performing a further reconstruction using the estimated vibrations; It has.

[0016] This is explained in detail below for the example shown in Figure 2.

[0017] According to one embodiment, the vibration correction method in step c2) comprises the steps of: segmenting bone structures in the reconstructed three-dimensional image; forward projecting the segmented bone structure onto the acquired projections of the projection data; aligning the forward projected bone structures with corresponding bone structures in the acquired projections to estimate vibrations of the C-arm X-ray imaging system during acquisition of the projection data; performing a further reconstruction using the estimated vibrations; It has.

[0018] This is explained in more detail below, particularly with respect to the example shown in FIG.

[0019] In a particular example, the forward projection and reconstruction are performed iteratively.

[0020] In a particular example, a segmented metal object or a segmented bone structure is forward projected onto an acquired projection with reduced resolution.

[0021] The computation time of iterative image reconstruction is often dominated by forward and backward projection operations. By using projections acquired with reduced resolution, the computation time can be significantly reduced.

[0022] In one embodiment, in step a) a three-dimensional image of the object of interest is reconstructed at a lower resolution than the final image reconstruction.

[0023] The initial reconstruction and all reconstructions within the vibration correction iterations may be performed at a lower resolution than the final image reconstruction to save computation time.

[0024] In a second aspect, there is provided a vibration artifact suppression apparatus comprising a processor configured to perform the steps of the method according to any one of the preceding claims.

[0025] In a third aspect, a C-arm X-ray imaging system configured to acquire projection data of an object of interest; a vibration artifact suppression apparatus according to the second aspect and any associated examples; An X-ray imaging system is provided having:

[0026] In certain embodiments, the C-arm X-ray imaging system is a mobile C-arm X-ray imaging system, for example, used in medical imaging.

[0027] In another aspect, there is provided a computer program having instructions which, when executed by a processor, cause the processor to perform the method steps of the third aspect and any associated examples.

[0028] In a further aspect of the present invention, there is provided a computer readable storage medium having stored thereon a computer program.

[0029] It should be understood that all combinations of the foregoing concepts and additional concepts discussed in more detail below (to the extent such concepts are not mutually inconsistent) are considered to be part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are considered to be part of the inventive subject matter disclosed herein.

[0030] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0031] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. [Brief explanation of the drawings]

[0032] [Figure 1] 1 shows a flow diagram illustrating an exemplary vibration artifact suppression method. [Figure 2] 1 shows a flow diagram of steps for performing a vibration correction method based on segmented metal objects in a reconstructed image, according to one embodiment. [Figure 3] 1 shows a flow diagram of steps for performing a vibration correction method based on a segmented object of interest in a reconstructed image, according to one embodiment. [Figure 4] Images processed with different numbers of vibration correction iterations for bone structures and metallic foreign bodies are shown. [Figure 5] 1 illustrates an exemplary X-ray imaging system. DETAILED DESCRIPTION OF THE INVENTION

[0033] 3D imaging with interventional C-arm systems is an area of ​​growing interest for many interventional procedures. For data collection, a motorized movement of the C-arc is performed to move the beam tube and detector around the region of interest. During this movement, projection data is acquired that can be used together with knowledge of the beam tube and detector positions to reconstruct a 3D image. Knowledge of the beam tube and detector positions is obtained from a geometric calibration procedure in which data acquisition is performed using precisely known geometric objects within the region of interest.

[0034] In the geometry data obtained from the calibration procedure, it can be observed that the C-arc oscillates during acquisition due to acceleration forces associated with the movement. Furthermore, from repeated calibrations, it can be seen that this oscillation changes in amplitude and phase for different acquisition runs. If the phase and / or amplitude of the oscillation pattern differs between the calibration procedure and the interventional data acquisition, significant image artifacts can occur that significantly impair image quality (see the top, left image of Figure 4).

[0035] To reduce these artifacts, vibration compensation (VC) methods have been developed. The methods begin with an initial reconstruction. In the first reconstruction, specific image structures are segmented and forward projected into the acquired projections. The forward projected structures are then aligned with corresponding structures in the original acquired projections to estimate vibration. Using the estimated vibration, a new reconstruction is performed that results in reduced vibration artifacts.

[0036] Vibrations in moving C-arm systems can be particularly large, significantly larger than in fixed systems, and the process may have to be repeated iteratively (see top row of Figure 4). That is, in an iterative process, vibration-corrected reconstructions are repeatedly used to segment and forward project bony structures, which are used to refine vibration estimates in another registration step. In the illustrated example (Figure 4, top row), the process is repeated four times to achieve an acceptable level of artifact suppression. Therefore, five image reconstructions, four forward projections, and four registrations must be performed, resulting in high computational time for the reconstruction.

[0037] It has been found that for images containing metal objects, the number of vibration correction iterations can be significantly reduced if the metal objects are segmented, forward projected, and used for registration. This is particularly interesting because, on these datasets after vibration correction, computationally very demanding metal artifact reduction (MAR) may be performed. According to the vibration artifact suppression method disclosed herein, the number of iterations can be strongly reduced, resulting in a significant speedup of the overall reconstruction time.

[0038] 1 shows a flow diagram illustrating an exemplary vibration artifact suppression method 100 according to an embodiment of the present disclosure. The vibration artifact suppression method 100 may be implemented as a device, module, or associated component in a set of logical instructions stored on a non-transitory machine- or computer-readable storage medium, such as random access memory (RAM), read-only memory (ROM), programmable ROM (PROM), firmware, flash memory, etc.; in configurable logic, such as a programmable logic array (PLA), field programmable gate array (FPGA), complex programmable logic device (CPLD), etc.; in fixed-function hardware logic using circuit technologies, such as application-specific integrated circuits (ASIC), complementary metal-oxide semiconductor (CMOS), or transistor-transistor logic (TTL) technology, etc.; or as any combination thereof. For example, computer program code for performing the operations shown in method 200 may be written in any combination of one or more programming languages, including object-oriented programming languages, such as JAVA, SMALLTALK, C++, Python, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. For example, the exemplary method may be implemented as an apparatus 30 shown in FIG.

[0039] In step 110, i.e., step a), the vibration artifact suppression method 100 includes reconstructing a 3D image of the object of interest based on projection data acquired by an X-ray imaging system, such as a movable C-arm system. The reconstructed image is also referred to as an initial reconstructed image or an initial image. In some examples, the projection data may be acquired by performing a scan using the X-ray imaging system. In some other examples, the projections may be acquired by retrieving previously acquired projection data from computer memory. The acquired projection data may be at the native resolution of the X-ray detector of the X-ray imaging system.

[0040] In some examples, the initial image may be generated using downsampled projection data and an image resolution of the initial image corresponding to the downsampled projection data. Downsampling of the projection data may be achieved using any known downsampling method. In some examples, fine-resolution pixels may be grouped into pixel groups corresponding to coarse-resolution pixels of the downsampled data, and the values ​​of each pixel group of fine-resolution pixels are then averaged or summed to generate a value for the coarse-resolution pixel. In some examples, the fine-resolution pixels may be resampled to a grid or other pixel pattern for the coarse-resolution pixels using interpolation, extrapolation, and / or integration from the fine-resolution grid to the coarse-resolution grid.

[0041] The initial reconstruction image may be generated using any known reconstruction method, including, but not limited to, filtered back projection (FBP), Feldkamp-Davis-Kress (FDK) reconstruction, and IR methods using an objective function with a least-squares method or a penalized weighted least-squares method, a fidelity term, and a regularization term.

[0042] In step 120, i.e., step b), the vibration artifact suppression method 100 includes determining whether the reconstructed three-dimensional image contains a metal object. The metal object may also be referred to as a metallic foreign object. The determination of whether the initial image contains a metal object can be performed in different ways.

[0043] In some examples, if the image values ​​are quantitatively correct Hounsfield Units (HU) values, a determination of whether the initial image contains metal can be made based on the number of voxel values ​​exceeding a specified threshold, where HU values ​​indicate a significant difference between anatomical structures and metallic foreign bodies. For example, the HU value of bone can range from +300 to +1900. Metallic foreign bodies typically have higher HU values. For example, copper has +14,000 HU, silver has +17,000 HU, steel has +20,000 HU, and gold has +30,000 HU. Therefore, an HU threshold can be defined to distinguish metallic foreign bodies from anatomical structures.

[0044] In some examples, if the image values ​​are not quantitatively correct HU values, a determination of whether the initial image contains metal can be made based on the histogram of the initial image. An image histogram is a distribution of grayscale values ​​indicating the frequency of occurrence of each gray level value. Histogram analysis is based on the assumption that the grayscale values ​​of anatomical structures and metal objects are distinguishable. This can result in the appearance of two peaks in the histogram. These peaks usually overlap, but the minimum between them can be found to separate both objects, for example, using a linear support vector machine. It is understood that the two objects can be separated using other AI-based (e.g., neural network) or non-AI-based methods based on the histogram of the initial image or the image itself.

[0045] In some examples, the determination of whether the initial image contains metal may be made based on user input, for example, via a graphical user interface (GUI).

[0046] Optionally, step 120 may further comprise determining the amount of metal objects in the reconstructed three-dimensional image, and determining based on the amount of metal objects whether to perform a vibration correction method based on the metal objects segmented in the reconstructed three-dimensional image. In other words, apart from simply determining whether the image contains metal, it may be confirmed whether sufficient metal structures are available to robustly estimate vibrations.

[0047] In some examples, the amount of metal objects may be determined based on the number of image slices in the projection data that have metal objects. For example, step 120 may further include determining how many image slices have significant portions of metal structures. A threshold value may be set for the number of image slices. If the number of image slices that have significant portions of metal structures is equal to or greater than this threshold value, it may be determined to perform a vibration correction method based on the metal objects segmented in the reconstructed three-dimensional image.

[0048] In some examples, the amount of metal objects may be determined based on the volume percentage of metal objects and / or the volume percentage of the convex hull of metal objects, as distribution within the field of view (FOV) is an important aspect for robust vibration correction.

[0049] If it is determined that the reconstructed three-dimensional image contains a metal object, the vibration artifact suppression method 100 proceeds from step 120 to step 130, i.e., step c1), where a vibration correction method is performed based on the metal object segmented in the reconstructed image. If no metal object is present, or the amount of metal is below a threshold, for example, the vibration artifact suppression method 100 proceeds from step 120 to step 140, i.e., step c2), where a vibration correction method is performed based on other image structures (e.g., bone structures) segmented in the reconstructed image.

[0050] FIG. 2 shows a flow diagram illustrating one embodiment of step 130.

[0051] In step 210 of step 130, metal objects in the reconstructed 3D image are segmented. In some examples, simple thresholding using either a fixed threshold or an estimated threshold for images with correct HU values, for example based on the image histogram, may be used to segment metal objects. In some examples, AI-based segmentation of metal objects, for example based on U-Net, may be performed.

[0052] In step 220 of step 130, once the metal object is segmented, the segmented metal object is forward projected onto the acquired projections. In some examples, the segmented metal object may be forward projected onto acquired projections with reduced resolution, for example, a low-resolution grid.

[0053] In step 230 of step 130, the forward projected metal object is aligned with the metal object in the acquired projections to estimate vibrations of the X-ray imaging system during acquisition of the projection data, which can be done by standard means already available for vibration correction based on bone structure, for example.

[0054] In step 240 of step 130, a further reconstruction is performed using the estimated vibration, resulting in reduced vibration artifacts.

[0055] To improve the situation, steps 210 to 240 can be repeated iteratively.

[0056] FIG. 3 shows a flow diagram illustrating one embodiment of step 140.

[0057] In step 310 of step 140, the object of interest (e.g., bone structure) in the reconstructed 3D image is segmented. In some examples, simple thresholding using either a fixed threshold (for images with correct HU values) or an estimated threshold, for example, based on the histogram of the image, can be used to segment the structure of interest for performing vibration correction, such as bone structure. In some examples, AI-based segmentation of the structure of interest, for example, based on U-Net, can be performed.

[0058] In step 320 of step 140, once the relevant structures have been segmented, the segmented structures are forward projected onto the acquired projections. In some examples, the segmented structures may be forward projected onto acquired projections having a lower resolution, for example, a lower resolution grid.

[0059] In step 330 of step 140, the forward projected structures are aligned with corresponding structures in the original projections acquired to estimate vibrations of the x-ray imaging system during acquisition of the projection data.

[0060] In step 340 of step 140, a further reconstruction is performed using the estimated vibration, resulting in reduced vibration artifacts.

[0061] To improve the situation, steps 310 to 340 may be repeated iteratively.

[0062] FIG. 4 shows images processed with different numbers of vibration correction iterations (from left to right) for bone structures and metal foreign bodies. The image shown in FIG. 4 includes a metal foreign body. The top row of FIG. 4 shows vibration correction based only on bone structures, and the bottom row of FIG. 4 shows vibration correction based on metal structures. As can be seen from FIG. 4, vibration artifacts, such as those indicated by the white arrow in the top left image, are suppressed significantly faster when vibration correction is based on metal structures.

[0063] 5 illustrates an exemplary X-ray imaging system 50 according to some embodiments of the present disclosure. Examples of X-ray imaging systems may include, but are not limited to, a C-arm system, a computed tomography (CT) system, a digital radiography (DXR) system, and an image-guided therapy (IGT) system. In some examples, the C-arm system may be a mobile C-arm system. The following description of the X-ray system 50 is merely an example of such an embodiment and is not intended to be limiting with respect to modality.

[0064] The X-ray imaging system 50 comprises an image acquisition device 10 , a reconstruction device 20 , and a vibration artifact suppression device 30 .

[0065] The image acquisition device 10 has an X-ray detector 16 facing the X-ray source 12. The image acquisition device 10 is configured to scan an object of interest 14 to generate projection data, i.e., a raw image, having one or more image slices, each representing a particular thickness of the object scanned at a particular projection angle.

[0066] The reconstructor 20 is configured to receive projection data acquired by performing a scan using the X-ray system 10 and determine an initial reconstructed image. The initial reconstructed image can be generated using any known reconstruction method. Examples of reconstruction methods for reconstructing a 3D image of an object of interest include, but are not limited to, filtered back projection (FBP), the Feldkamp-Davis-Kress (FDK) reconstruction method, and an IR method using an objective function with a least-squares method or a penalized weighted least-squares method, a fidelity term, and a regularization term. The reconstructor 20 then provides the initial reconstructed image to the vibration artifact suppression device 30.

[0067] The vibration artifact suppression device 30 is configured to perform the vibration artifact suppression methods disclosed herein, such as the method shown in FIG. 1, to obtain reconstructed images with reduced vibration artifacts.

[0068] In general, vibration artifact suppression apparatus 30 may have various physical and / or logical components that communicate and manipulate information, which may be implemented as hardware components (e.g., computing devices, processors, logic devices), executable computer program instructions (e.g., firmware, software) executed by the various hardware components, or any combination thereof, as desired for a given set of design parameters or performance constraints. While FIG. 5 shows a limited number of components by way of example, it can be understood that a greater or lesser number of components may be used for a given implementation.

[0069] In some embodiments, the vibration artifact suppression apparatus 30 may be embodied as or within a device or apparatus, such as a server, workstation, or mobile device. The apparatus 10 may have one or more microprocessors or computer processors that execute appropriate software. For example, the vibration artifact suppression apparatus 30 may have a processing unit that may be implemented by one or more of these processors. The software may be downloaded and / or stored in corresponding memory, e.g., volatile memory such as RAM or non-volatile memory such as flash. The software may include instructions that configure the one or more processors to perform the functions described herein.

[0070] It should be noted that the vibration artifact suppression apparatus 30 may be implemented with or without a processor, and may be implemented as a combination of dedicated hardware that performs some functions and a processor (e.g., one or more programmed microprocessors and associated circuitry) that performs other functions. For example, the vibration artifact suppression apparatus 30 may be implemented in a device or apparatus in the form of programmable logic, such as a field programmable gate array (FPGA). In general, each functional unit of the apparatus may be implemented in the form of a circuit.

[0071] In some embodiments, vibration artifact suppression apparatus 30 may be implemented in a distributed manner. For example, some or all units of apparatus 10 may be configured as separate modules in a distributed architecture and connected to a suitable communication network, such as a 3rd Generation Partnership Project (3GPP) network, a Long Term Evolution (LTE) network, the Internet, a LAN (Local Area Network), a wireless LAN (Local Area Network), a WAN (Wide Area Network), etc.

[0072] Although FIG. 5 shows the reconstruction device 20 and the vibration artifact suppression device 30 as two separate devices as an example, in some other examples the vibration artifact suppression device 30 may reside within the reconstruction device 20, for example, implemented as software. In another exemplary embodiment of the invention, a computer program or a computer program element is provided, characterized in that it is configured to perform, on a suitable system, the method steps of the method according to one of the previous embodiments.

[0073] Thus, a computer program element may be stored on a computing unit that may be part of an embodiment of the present invention. This computing unit may be configured to perform or direct the performance of the steps of the above-mentioned method. Furthermore, it may be configured to operate the components of the above-mentioned apparatus. The computing unit may be configured to operate automatically and / or to execute a user's order. The computer program may be loaded into the working memory of a data processor. The data processor may thus be equipped to perform the method of the present invention.

[0074] This exemplary embodiment of the present invention encompasses both computer programs that use the present invention from the beginning, and computer programs that convert existing programs into programs that use the present invention by means of an update.

[0075] Furthermore, the computer program element may be capable of providing all the steps necessary to fulfill the procedures of the exemplary embodiments of the methods described above.

[0076] According to a further exemplary embodiment of the present invention, a computer readable medium, such as a CD-ROM, is presented, the computer readable medium having stored thereon computer program elements, the computer program elements being described by the preceding sections.

[0077] The computer program may be stored and / or distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunications systems.

[0078] However, the computer program may also be presented over a network such as the World Wide Web and can be downloaded into the working memory of a data processor from such a network. According to a further exemplary embodiment of the present invention, a medium for making a computer program element available for downloading is provided, the computer program element being configured to perform a method according to one of the aforementioned embodiments of the present invention.

[0079] It should be noted that the embodiments of the present invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method-type claims, and other embodiments are described with reference to apparatus-type claims. However, those skilled in the art will understand from the above and below description that, unless otherwise specified, any combination of features belonging to one type of subject matter, as well as any combination between features relating to different subject matters, is considered to be disclosed in the present application. However, all features can be combined to provide a synergistic effect greater than the simple sum of the features.

[0080] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered exemplary or explanatory and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the dependent claims.

[0081] In the claims, the word "comprise" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be interpreted as limiting the scope.

Claims

1. a) reconstructing a three-dimensional image of an object of interest based on projection data acquired with an X-ray imaging system; b) determining whether the reconstructed three-dimensional image contains a metal object; c) performing a vibration correction method based on the segmented structures of interest in the reconstructed three-dimensional image, the structures of interest being selected based on the results of the determining step; 1. A vibration artifact suppression method comprising:

2. wherein the structure of interest is a metal object, and step c) comprises: c1) performing the vibration correction method based on the metal object; 2. The vibration artifact suppression method of claim 1, comprising:

3. Step c1) further comprises determining an amount of the metal objects in the reconstructed three-dimensional image, and determining whether to perform the vibration correction method based on the metal objects segmented in the reconstructed three-dimensional image based on the amount of the metal objects. The vibration artifact suppression method of claim 2 .

4. The amount of the metal object is the number of image slices in the projection data that have the metal object; the volume percentage of the metal objects; or the volume percentage of the convex hull of the metal object; determined based on at least one of The vibration artifact suppression method of claim 3 .

5. The vibration correction method in step c1) comprises: segmenting the metal object in the reconstructed three-dimensional image; forward projecting the segmented metal object onto a projection of the acquired projection data; aligning the forward projected metal object with the metal object in the acquired projections to estimate vibrations of the X-ray imaging system during acquisition of the projection data; performing a further reconstruction using the estimated vibrations; having A vibration artifact suppression method according to any one of claims 2 to 4.

6. wherein the structure of interest is a bone structure, and step c) comprises: c2) performing the vibration correction method based on the segmented bone structures in the reconstructed 3D image; 2. The vibration artifact suppression method of claim 1, comprising:

7. The vibration correction method in step c2) comprises: segmenting the bone structure in the reconstructed three-dimensional image; forward projecting the segmented bone structure onto a projection of the acquired projection data; - registering the forward projected bone structures with corresponding bone structures in the acquired projections to estimate vibrations of the X-ray imaging system during acquisition of the projection data; performing a further reconstruction using the estimated vibrations; having The vibration artifact suppression method of claim 6.

8. The forward projection and reconstruction are performed iteratively.

8. A vibration artifact suppression method according to claim 5 or 7.

9. - the segmented metal object or bone structure is forward projected onto the acquired projections with reduced resolution; A vibration artifact suppression method according to any one of claims 5 to 8.

10. In step a), the three-dimensional image of the object of interest is reconstructed at a lower resolution than the final image reconstruction. A vibration artifact suppression method according to any one of claims 1 to 9.

11. 11. A vibration artifact suppression device comprising a processor configured to perform the steps of the method of any one of claims 1 to 10.

12. an x-ray imaging system configured to acquire projection data of an object of interest; A vibration artifact suppression device according to claim 11; An X-ray imaging system comprising:

13. the X-ray imaging system is a movable C-arm X-ray imaging system. The X-ray imaging system of claim 12.

14. A computer program comprising instructions which, when executed by a processor, cause the processor to perform the steps of the method according to any one of claims 1 to 10.

15. A computer-readable storage medium storing the computer program according to claim 14.

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