Image reconstruction method and device and computer readable storage medium

Abstract

The invention relates to an image reconstruction method and device and a computer readable storage medium. The method comprises the steps that phase difference information between at least two times of excitation executed for an object at different moments is determined; based on the phase difference information, correcting the to-be-corrected imaging data obtained through the at least two times of excitation to obtain corrected imaging data; and obtaining a reconstructed image of the object based on the corrected imaging data. By adopting the method, the accuracy of phase correction in the magnetic resonance imaging process can be ensured.

Description

Technical Field

[0001] This application relates to the field of image processing technologies, and in particular, to an image reconstruction method, apparatus, and computer-readable storage medium. Background Art

[0002] In the process of magnetic resonance imaging in related technologies, in order to correct the phase change of multiple excitations, immediately after each excitation of the target image acquisition, a low-resolution reference scan image is quickly acquired, and the target image is phase-corrected by the reference scan image. Since the phase change of the reference scan image is uncontrollable, the accuracy of phase correction cannot be well guaranteed. Summary of the Invention

[0003] Based on this, in view of the above technical problems, it is necessary to provide an image reconstruction method, apparatus, and computer-readable storage medium that can ensure the accuracy of phase correction during magnetic resonance imaging.

[0004] In a first aspect, this application provides an image reconstruction method, which includes:

[0005] Determine the phase difference information between at least two excitations performed on an object at different times;

[0006] Based on the above phase difference information, correct the to-be-corrected imaging data obtained by at least two excitations to obtain corrected imaging data; and

[0007] Based on the corrected imaging data, obtain a reconstructed image of the object.

[0008] In one embodiment, the above determination of the phase difference information between at least two excitations performed on an object at different times includes:

[0009] Based on the phase information corresponding to at least two excitations, determine a phase difference map of the excitation images obtained by at least two excitations; and

[0010] Perform artifact removal processing on the phase difference map to obtain the phase difference information of the target region corresponding to the object in the excitation images of at least two excitations.

[0011] In one embodiment, the above performing artifact removal processing on the phase difference map to obtain the phase difference information of the target region corresponding to the object in the excitation images of at least two excitations includes:

[0012] Obtain a preset mask that matches the phase difference map; and

[0013] Based on the preset mask, remove or reduce the influence of the artifact data included in the phase difference map to obtain the phase difference information.

[0014] In one embodiment, based on the phase difference information, correcting the to-be-corrected imaging data obtained by at least two excitations to obtain corrected imaging data, including:

[0015] In the excitation images obtained based on at least two excitations, determining a reference image; and

[0016] Based on the phase difference information, performing phase correction on the other excitation images except the reference image to obtain a corrected image whose phase matches the phase of the reference image.

[0017] In one embodiment, based on the phase difference information, performing phase correction on the other excitation images except the reference image to obtain a corrected image whose phase matches the phase of the reference image, including:

[0018] In the other excitation images, determining a target region corresponding to the object; and

[0019] Based on the phase difference information, performing phase correction on the target region in the other excitation images to obtain a corrected image.

[0020] In one embodiment, based on the corrected imaging data, obtaining a reconstructed image of the object, including:

[0021] Fusing the imaging data corresponding to the object in the corrected imaging data to obtain fused imaging data; and

[0022] Based on the fused imaging data, obtaining a reconstructed image of the object.

[0023] In one embodiment, after determining the phase difference information between at least two excitations performed on the object at different times, the method further includes:

[0024] In the case where the phase difference information does not meet the preset condition, performing at least one excitation on the object to re-obtain updated imaging data, and updating the phase difference information based on the phase information of the updated imaging data.

[0025] In one embodiment, the method further includes:

[0026] Exciting the object under each part of the data space in the same data space to obtain single-excitation imaging data corresponding to each part of the data space; and

[0027] Based on the single-excitation imaging data corresponding to different parts of the data space in the same data space, obtaining the to-be-corrected imaging data.

[0028] In a second aspect, the present application further provides an image reconstruction device, and the device includes:

[0029] A determination module, configured to determine phase difference information between at least two excitations performed on an object at different times;

[0030] A correction module, configured to correct the imaging data to be corrected obtained through at least two excitations based on the phase difference information, to obtain corrected imaging data; and

[0031] A reconstruction module, configured to obtain a reconstructed image of the object based on the corrected imaging data.

[0032] In a third aspect, the present application further provides a computer device, which includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0033] Determine phase difference information between at least two excitations performed on an object at different times;

[0034] Based on the phase difference information, correct the imaging data to be corrected obtained through at least two excitations, to obtain corrected imaging data; and

[0035] Based on the corrected imaging data, obtain a reconstructed image of the object.

[0036] In a fourth aspect, the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0037] Determine phase difference information between at least two excitations performed on an object at different times;

[0038] Based on the phase difference information, correct the imaging data to be corrected obtained through at least two excitations, to obtain corrected imaging data; and

[0039] Based on the corrected imaging data, obtain a reconstructed image of the object.

[0040] In a fifth aspect, the present application further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the following steps are implemented:

[0041] Determine phase difference information between at least two excitations performed on an object at different times;

[0042] Based on the phase difference information, correct the imaging data to be corrected obtained through at least two excitations, to obtain corrected imaging data; and

[0043] Based on the corrected imaging data, obtain a reconstructed image of the object.

[0044] The above image reconstruction method, apparatus, and computer-readable storage medium determine phase difference information between at least two excitations performed on an object at different times, correct uncorrected imaging data obtained through at least two excitations based on the phase difference information to obtain corrected imaging data, and obtain a reconstructed image of the object based on the corrected imaging data. In this method, since the phase difference information of the uncorrected imaging data obtained through at least two excitations is used for phase self-correction of the uncorrected imaging data, it is possible to ensure that the phases of the imaging data of at least two excitations are consistent, that is, the accuracy of phase correction in the magnetic resonance imaging process can be ensured. Therefore, a relatively accurate reconstructed image can also be obtained through the corrected imaging data with consistent phases. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is an internal structure diagram of a computer device in one embodiment;

[0046] Figure 2 is a schematic flowchart of an image reconstruction method in one embodiment;

[0047] Figure 3 is a schematic flowchart of an image reconstruction method in another embodiment;

[0048] Figure 4 is a schematic flowchart of an image reconstruction method in another embodiment;

[0049] Figure 5 is a schematic flowchart of an image reconstruction method in another embodiment;

[0050] Figure 6 is a schematic flowchart of an image reconstruction method in another embodiment;

[0051] Figure 7 is a schematic diagram of two-excitation magnetic resonance image phase correction reconstruction based on reference scanning;

[0052] Figure 8 is a schematic flowchart of phase difference information calculation in another embodiment;

[0053] Figure 9 is a schematic diagram of two-excitation magnetic resonance imaging phase self-correction reconstruction in another embodiment;

[0054] Figure 10 is a structural block diagram of an image reconstruction apparatus in one embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0055] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0056] The magnetic resonance image is obtained by performing an inverse Fourier transform on the originally acquired k-space data. It is a complex image and includes two parts: amplitude and phase. The multi-shot magnetic resonance image refers to an image obtained by multi-shot acquisition, that is, only a part of the k-space is acquired each time of excitation, and the k-spaces acquired by multi-shot acquisitions together form a complete k-space. Ideally, the target image can be obtained by performing an inverse Fourier transform on this k-space. However, in practical applications, due to the movement of the scanned object during multi-shot excitations or the change of the magnetic resonance system state, the k-space data acquired by different excitations is "inconsistent", and there are phase differences in the images obtained by multi-shot excitations, which are reflected as artifacts in the images. Currently, in order to correct the phase change of multi-shot excitations, a low-resolution reference scan image can be quickly acquired immediately after each target image acquisition. Since the reference scan k-space corresponding to this reference scan image is not undersampled, there is no aliasing in the image, so the phase change of the reference scan image acquired by multi-shot excitations can be used to correct the phase change of the target image. However, the prerequisite for phase correction using the reference image is that the phase changes of the reference image and the target image are consistent. However, in practical applications, it is difficult to ensure that this prerequisite is met, that is, currently, due to the uncontrollable phase change of the reference scan image, the accuracy of phase correction cannot be well guaranteed. Based on this, the embodiments of the present application provide an image reconstruction method, device and computer-readable storage medium, which can solve this technical problem.

[0057] The image reconstruction method provided by the embodiments of the present application can be applied to a computer device. This computer device can be a terminal or a server. Taking the terminal as an example, its internal structure diagram can be as Figure 1As shown in the figure. The computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected via a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner. The wireless manner can be implemented through WIFI, a mobile cellular network, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements an image reconstruction method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covering the display screen, or a button, a trackball, or a touchpad provided on the casing of the computer device, or an external keyboard, touchpad, or mouse, etc.

[0058] Those skilled in the art can understand that Figure 1 the structure shown in the figure is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0059] In one embodiment, as shown in Figure 2 the figure, an image reconstruction method is provided. Taking the computer device in Figure 1 as an example for description, the method may include the following steps:

[0060] S202, determine the phase difference information between at least two excitations performed on an object at different times.

[0061] Among them, the object can be the whole of a human body, an animal body, or an object, or a certain part of a human body, an animal body, or an object, such as the chest or brain of a human body, etc.

[0062] Generally, a magnetic resonance image is obtained by performing an inverse Fourier transform on the originally acquired K-space data, and it is a complex image consisting of two parts: amplitude and phase. A multi-shot magnetic resonance image refers to an image obtained by performing multiple excitations and acquisitions on an object. The K-space data obtained from multiple excitations and acquisitions can be combined to obtain complete K-space data. However, the applicant has found that in practical applications, due to the movement of the scanned object during multiple excitations or changes in the state of the magnetic resonance system, the K-space data obtained from different excitations and acquisitions is "inconsistent", and there are differences in the image phase, which are reflected as artifacts in the image. Therefore, the applicant has realized that the phase difference information between each excitation can be determined (for example, by determining the phase information corresponding to each excitation and calculating the phase difference information), and then the imaging data can be corrected based on this, and then a reconstructed image can be obtained from this to determine and eliminate the artifacts caused by "inconsistency".

[0063] Specifically, the object can be excited multiple times by a scanning device at different times, where the object can be excited once at each time, and the imaging data of the object corresponding to each excitation can be obtained after each excitation. In this article, the imaging data can include the data directly obtained by excitation and / or any data indirectly obtained by excitation, for example, K-space data, an image reconstructed based on the K-space data, etc. Exemplarily, the above scanning device can be, for example, an MR (Magnetic Resonance) scanning device, and the imaging data obtained after the above excitation can be magnetic resonance imaging data or a magnetic resonance image or a magnetic resonance reconstructed image, etc.

[0064] In addition, when the object is excited multiple times, each excitation can be to collect only a part of the imaging data of the object in the K-space, or each excitation can be to collect all the imaging data of the object in the K-space. For the case where each excitation can be to collect only a part of the imaging data of the object in the K-space, the imaging data collected by each excitation can correspond to different parts / different positions in the K-space, that is, the imaging data collected by multiple excitations can together constitute a complete K-space.

[0065] Furthermore, when the object is excited multiple times, the phase information corresponding to each excitation can be obtained, and then the phase difference information between multiple excitations can be obtained by calculating or processing the phase information of each excitation. Alternatively, the phase difference information between multiple excitations can also be directly obtained during each excitation, and the obtaining methods include, but are not limited to, determining by reading pre-stored data, determining by experience, or determining by device parameters, etc. The phase difference information here can represent the phase difference situation or phase change situation between multiple excitations.

[0066] In addition, when the phase difference information between multiple excitations is actually obtained, it is possible that the obtained phase difference information is abnormal (such as the case where the phase difference is too large), which will affect the subsequent phase correction accuracy and image reconstruction accuracy. Therefore, to avoid this problem, as an alternative embodiment, when the phase difference information does not meet the preset conditions, at least one excitation is performed on the object to re-obtain the updated imaging data, and based on the phase information of the updated imaging data, the above-mentioned phase difference information is updated.

[0067] Among them, the above-mentioned preset conditions represent the conditions for normal phase difference information. After obtaining the phase difference information, it can be detected whether the phase difference information meets the preset conditions, that is, whether it is normal; if the phase difference information does not meet the preset conditions, that is, there is an abnormality, the object can be excited one or more times again to obtain the imaging data of each excitation, and the imaging data corresponding to this excitation before can be updated by using the imaging data of each excitation, and finally the updated imaging data is obtained. Then, the phase difference information between them can be updated based on the phase information of the updated imaging data until the updated phase difference information meets the preset conditions, and the final phase difference information is obtained. The finally obtained phase difference information meets the preset conditions, so the subsequent phase correction accuracy and image reconstruction accuracy can be guaranteed.

[0068] S204, based on the above-mentioned phase difference information, correct the imaging data to be corrected obtained by at least two excitations to obtain the corrected imaging data.

[0069] In this step, after obtaining the phase difference information of multiple excitations, the phase difference situation or phase change situation between the imaging data of each excitation can be obtained, and then the imaging data to be corrected of each excitation can be corrected according to this phase difference situation or phase change situation to obtain the finally corrected corrected imaging data. It should be noted that the correction here is mainly for the phase of the imaging data.

[0070] Exemplarily, for instance, the imaging data of a certain excitation can be used as the reference imaging data, and the imaging data of other excitations can be corrected to this reference imaging data according to the phase difference information to obtain the corrected imaging data corresponding to other excitations. Then, the corrected imaging data and the reference imaging data are combined to obtain (or denoted as) the corrected imaging data. Alternatively, it is also possible to correct the imaging data of each excitation through the phase difference information (for example, correct the imaging data of each excitation to a certain standard space) to correct the imaging data of each excitation well, and finally obtain the corrected imaging data. As a non-limiting example, the phase of the imaging data of other excitations can be adjusted to be consistent with the phase of the reference imaging data, and based on the adjusted phase, the corresponding imaging data of other excitations is adjusted, and then the above-mentioned corrected imaging data is obtained by combination. It should be noted that in some cases, it is also possible to correct the imaging data of some excitations instead of all the imaging data. Or, other correction methods can also be adopted. In short, as long as the correction of the imaging data can be achieved, it is not specifically limited here.

[0071] S206. Based on the corrected imaging data, obtain the reconstructed image of the object.

[0072] In this step, after obtaining the corrected imaging data above, taking the corrected imaging data as the data in the K space as an example, a Fourier transform algorithm can be used to perform inverse Fourier transform processing and other reconstruction processing on the corrected imaging data to obtain the reconstructed image of the object. This reconstructed image can be, for example, a magnetic resonance image. In addition, taking the corrected imaging data as the corrected excitation image as an example, an image fusion algorithm or the like can be used to obtain the reconstructed image of the object. Here, the excitation image can be obtained based on excitation. For example, by performing one or more excitations on the object to obtain the corresponding K space data and performing image reconstruction (for example, image reconstruction based on inverse Fourier transform), the excitation image corresponding to each excitation is obtained. Or, other image reconstruction algorithms can also be used to perform image reconstruction on the corrected imaging data. In short, as long as the reconstructed image can be obtained, the specific image reconstruction algorithm is not limited here.

[0073] As can be seen from the above description, in the phase correction process of this embodiment, the phase difference information in at least two excitations itself can be used for phase self-correction, without relying on a reference scan image as a "medium" for phase correction. In this way, the phase error between the two excitation images can be effectively corrected, and thus the accuracy of phase correction can also be significantly improved. At the same time, compared with the phase correction algorithm that needs to rely on a reference scan image, the method of this embodiment does not require a reference scan image and can basically meet the phase correction in common scenarios.

[0074] In the above image reconstruction method, by determining the phase difference information between at least two excitations performed on an object at different times, and correcting the imaging data to be corrected obtained through at least two excitations based on the phase difference information, corrected imaging data is obtained, and based on the corrected imaging data, a reconstructed image of the object is obtained. In this method, since the phase difference information of the imaging data to be corrected obtained through at least two excitations is used for phase self-correction of the imaging data to be corrected, it is possible to ensure that the phases of the imaging data of at least two excitations are consistent, that is, the accuracy of phase correction in the magnetic resonance imaging process can be ensured. Thus, a relatively accurate reconstructed image can also be obtained through the corrected imaging data with consistent phases.

[0075] In the above embodiments, it is mentioned that the phase difference information between multiple excitations can be calculated. The following embodiments will illustrate a calculation method for this phase difference information.

[0076] In another embodiment, another image reconstruction method is provided. On the basis of the above embodiments, as Figure 3 shown, the above S202 may include the following steps:

[0077] S302, based on the phase information corresponding to at least two excitations, determine a phase difference map of the excitation images obtained based on at least two excitations.

[0078] In this step, as mentioned above, during each excitation process, an excitation image corresponding to each excitation can be obtained, and at the same time, the phase information of each excitation image of each excitation can be obtained. Then, by calculating the differences between the phase information of the excitation images, a phase difference map can be obtained. As a non-limiting specific example, based on the K-space data obtained from each excitation, an excitation image can be reconstructed through inverse Fourier transform, and based on this excitation image, its corresponding phase information can be determined, and then the differences between them can be calculated to determine the phase difference map.

[0079] S304, perform artifact removal processing on the phase difference map to obtain the phase difference information of the target region corresponding to the object in the excitation images of at least two excitations.

[0080] Among them, the target region may be, for example, a region containing the object or a part of it. In this step, after obtaining the phase difference maps of each excitation, since there may be artifacts in the phase difference map, the phase difference map can be subjected to artifact removal processing. Here, the artifact removal processing can be, for example, using a neural network, manual processing, or other methods to perform artifact removal processing on the regions with artifacts in the phase difference map. Of course, other methods can also be used for artifact removal processing. Finally, a phase difference map without artifacts can be obtained, and through this phase difference map without artifacts, the phase difference information of the target region without artifacts can be obtained.

[0081] For the above artifact removal process, as an optional embodiment, for example, it may be to obtain a preset mask that matches the phase difference map; and based on the preset mask, remove or reduce the artifact data included in the phase difference map and / or other data errors caused by the artifact data (these can all be regarded as the influence of the artifact data) to obtain phase difference information. Among them, the preset mask can be a mask image that matches the size of the phase difference map and includes the above-mentioned target area and other areas. The preset mask can be, for example, a binary mask image, where the target area and other areas can be set to different values, so that the target area and other areas can be quickly distinguished through the preset mask. Then, the phase difference map can be subjected to difference operations with the preset mask, etc., to remove or reduce the artifact data in other areas in the phase difference map and screen out the phase difference information of the target area.

[0082] In this embodiment, by determining the phase difference map based on the phase information of at least two excitations and performing artifact removal processing on the phase difference map to obtain the phase difference information of the target area corresponding to the object, here, by obtaining the phase difference map and performing artifact removal, the phase difference information can be obtained quickly and accurately. Further, by using a preset mask that matches the phase difference map to perform artifact removal processing on the phase difference map, the artifact removal processing of the phase difference map can be more accurately realized, further improving the accuracy of the obtained phase difference information, and then improving the accuracy of subsequent phase correction.

[0083] In the above embodiment, it is mentioned that the imaging data can be corrected through the phase difference information. The following embodiment will illustrate the correction process of the imaging data.

[0084] In another embodiment, another image reconstruction method is provided. On the basis of the above embodiment, as Figure 4 shown, the above S204 may include the following steps:

[0085] S402, in the excitation images obtained based on at least two excitations, determine a reference image.

[0086] In this step, as mentioned above, each excitation can obtain an excitation image (corresponding to the imaging data). After obtaining the excitation images of each excitation, in order to facilitate the subsequent correction of the imaging data, an excitation image can be determined from them as the reference image.

[0087] The determination method of the reference image here can be set according to the actual situation. For example, the excitation image of the first excitation can be used as the reference image, or the image of the last excitation can be used as the reference image, or the excitation images of other excitations can also be used as the reference image.

[0088] S404. Perform phase correction on other excitation images except the reference image based on the phase difference information to obtain corrected images with phases matching that of the reference image.

[0089] In this step, after obtaining the phase difference information, the phase difference information can be that of the entire region or the target region. Then, based on this phase difference, phase correction can be performed on other excitation images to make the phase changes among the excitation images consistent, and finally, the corrected images corresponding to the other excitation images are obtained. Then, the corrected images and the reference image can be jointly used as the corrected imaging data mentioned above.

[0090] Exemplarily, assume that the phase difference map is the phase of the first excitation image minus the phase of the second excitation image, and the difference is 5. Then, the first excitation image can be subtracted by 5, or the second excitation image can be added by 5. In short, the phase changes of the two excitation images are made consistent.

[0091] In addition, to further improve the efficiency and accuracy of phase correction, as an optional embodiment, in other excitation images, a target region corresponding to the object can be determined. As an example, the target region is the region where the object is located or the region representing the object. Based on the phase difference information, phase correction is performed on the target region in other excitation images to obtain corrected images. That is to say, the phase difference information can be, for example, that of the target region. Then, the target region is determined in each excitation image, and then phase correction is performed on the target region of other excitation images through the phase difference information to obtain the corrected images corresponding to the other excitation images.

[0092] In this embodiment, after determining the reference image in the excitation images of at least two excitations, phase correction is performed on other excitation images based on the phase difference information to obtain corrected images with phase matching. In this way, the method of determining the reference image and correcting other images is relatively simple and intuitive, so the efficiency and accuracy of phase correction can be improved. Further, phase correction can be performed on the target region in other excitation images through the phase difference information, which can improve the efficiency and accuracy of phase correction.

[0093] In the above embodiment, it is mentioned that the imaging data can be corrected through the phase difference information. The following embodiment will illustrate the correction process of this imaging data.

[0094] In another embodiment, another image reconstruction method is provided. On the basis of the above embodiment, as Figure 5 shown, the above S206 may include the following steps:

[0095] S502. Fuse the imaging data corresponding to the object in the calibrated imaging data to obtain fused imaging data.

[0096] As an example, in this step, if the calibrated imaging data includes calibrated images, the target regions corresponding to the object in each calibrated image can be fused to obtain the fused imaging data. In addition, if the calibrated imaging data includes calibrated k-space data, the k-space data corresponding to the object in each calibrated k-space data can be fused to obtain the fused imaging data. As a non-limiting example, the imaging data can be fused by weighted superposition, direct superposition, etc.

[0097] S504. Based on the fused imaging data, obtain the reconstructed image of the object.

[0098] Among them, as a non-limiting example, when the fused imaging data is fused k-space data, the inverse Fourier transform can be performed on the fused data to obtain the reconstructed image of the object; when the fused imaging data is a fused image, the reconstructed image of the object can be obtained directly or after post-processing (such as further artifact removal, verification, etc.).

[0099] In this embodiment, by fusing the imaging data corresponding to the object in the calibrated imaging data, the reconstructed image of the object is obtained, which can improve the efficiency and accuracy of image reconstruction.

[0100] In the above embodiment, it is mentioned that the excitation image for each excitation can be obtained. The following embodiments will illustrate the specific process of obtaining the excitation image.

[0101] In another embodiment, another image reconstruction method is provided. Based on the above embodiment, as Figure 6 shown, the above method may further include the following steps:

[0102] S602. Excite the object under each part of the data space in the same data space to obtain the single-shot excitation imaging data corresponding to each part of the data space.

[0103] In this step, the data space may be the k-space corresponding to magnetic resonance imaging. Specifically, each time the object is excited, the imaging data of a part of the data space in the k-space is obtained. Among them, each excitation may be the imaging data corresponding to different parts of the data space in the same k-space, so that the single-shot excitation imaging data of each part of the data space can be obtained.

[0104] Further, to ensure the accuracy of subsequent phase correction, after obtaining each single-shot imaging data, the data quality of each single-shot imaging data can be determined (for example, specifically, the data quality of the target region in each single-shot imaging data), and then, when it is detected that the data quality of the single-shot imaging data does not meet the preset data quality threshold, the object is re-scanned by magnetic resonance in each part of the data space to obtain single-shot imaging data whose data quality meets the preset data quality threshold, that is, to obtain single-shot imaging data with higher data quality, which can effectively improve the accuracy of subsequent phase correction. In addition, the specific size of the preset data quality threshold here can be set according to the actual situation.

[0105] S604. Obtain the imaging data to be corrected based on the single-shot imaging data corresponding to different parts of the data space in the same data space.

[0106] In this step, after obtaining multiple single-shot imaging data (for example, K-space data or images), each single-shot imaging data can be used as the imaging data to be corrected corresponding to the at least two excitations mentioned above.

[0107] In this embodiment, by exciting the object in each part of the data space in the same data space to obtain the single-shot imaging data corresponding to each part of the data space, and then obtaining the excitation imaging data corresponding to at least two excitations, relatively complete imaging data of the data space can be obtained, and thus the comprehensiveness of subsequent phase correction can be improved.

[0108] A detailed embodiment is given below to illustrate the technical solution of the present application. On the basis of the above embodiment, the above method may include the following steps:

[0109] S1. Excite the object in each part of the data space in the same data space to obtain the single-shot imaging data corresponding to each part of the data space;

[0110] S2. Obtain the imaging data to be corrected obtained by at least two excitations (for example, the excitation images obtained by at least two excitations) based on the single-shot imaging data corresponding to different parts of the data space in the same data space;

[0111] S3. Determine the phase difference map of the excitation images obtained by at least two excitations based on the phase information corresponding to the at least two excitations;

[0112] S4. Obtain the preset mask that matches the phase difference map;

[0113] S5. Remove or reduce the influence of the artifact data included in the phase difference map based on the preset mask to obtain the phase difference information;

[0114] S6. When the phase difference information does not meet the preset conditions, re-acquire the updated imaging data by performing at least one excitation on the object, and update the above-mentioned phase difference information based on the phase information of the updated imaging data;

[0115] S7. Determine a reference image among the excitation images obtained based on at least two excitations;

[0116] S8. In other excitation images, determine the target region corresponding to the object (for example, the target region where the object is located or its periphery);

[0117] S9. Based on the phase difference information, perform phase correction on the target region in other excitation images to obtain the corrected imaging data;

[0118] S10. Fuse the imaging data corresponding to the object in the corrected imaging data to obtain the fused imaging data;

[0119] S11. Based on the fused imaging data, obtain the reconstructed image of the object.

[0120] The method of this embodiment will be described in detail below in combination with the existing method of performing phase correction using a reference scan image.

[0121] Exemplarily, referring to Figure 7 the schematic diagram of the two-excitation magnetic resonance image phase correction and reconstruction algorithm based on reference scanning shown. As mentioned above, for the reconstruction algorithm of using a reference scan image to perform phase correction on a target image, a prerequisite needs to be met: the reference scan images collected by multiple excitations can accurately reflect the phase change of the target image. When this prerequisite is met, the phase change of the target image can be effectively corrected using the reference scan image to obtain a target image without artifacts, as shown by the multiple images in the first row of Figure 7 Conversely, the phase of the target image cannot be corrected using the reference scan image, resulting in serious artifacts in the reconstructed target image, as shown by the multiple images in the second row of Figure 7 Among them, the image in the first column of the first row and the second row is an example diagram of the phase change of the target image, the second column is an example diagram of the phase change of the reference scan image, and the third column is the reconstructed image. It can be seen from this that the reference scan images collected by multiple excitations can accurately correct the phase of the target image only when they can accurately reflect the phase change of the target image.

[0122] Exemplarily, taking the magnetic resonance images of two excitations as an example, for the magnetic resonance images of two excitations, although there are artifacts similar to "N / 2 ghost" in the images of a single excitation, in most cases, the artifacts will not contaminate the target image, as described above in Figure 7As shown in the left image. Exemplarily, when the target image is located in the central region of the image obtained by magnetic resonance imaging or near it, artifacts basically do not contaminate the target image. Therefore, the phase self-correction can be performed by using the phase change between the two excitation images of the target image. In addition, in order to remove the influence of artifacts, a masking process can be performed on the phase difference map of the two excitations, so that the phase change (i.e., phase difference information) of the target image can be obtained, and the influence of the artifact phase can be eliminated. The specific calculation process of the phase difference information can be referred to Figure 8 the flowchart shown. The excitation images can be obtained by performing an inverse Fourier transform on the raw K-space data of at least two excitations, and then the phase difference between the two excitation images is used to obtain the phase difference of the central target image through a masking process. Using this phase difference information for self-correction of the target image, a reconstructed image without obvious artifacts can be obtained. The specific obtained image can be referred to Figure 9 the schematic diagram of the phase self-correction reconstruction algorithm for two-excitation magnetic resonance imaging shown. It can be seen that the accuracy of the reconstructed image obtained by using the method of the embodiment of the present application is relatively high.

[0123] It should be noted that the above Figure 7 、 9 The attached drawings in are only examples and do not affect the substantial content of the embodiments of the present application.

[0124] It should be understood that although the steps in the flowcharts involved in the above-mentioned embodiments are sequentially shown according to the indications of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or steps in other steps.

[0125] Based on the same inventive concept, the embodiment of the present application also provides an image reconstruction device for implementing the above-mentioned image reconstruction method. The solution provided by this device to solve the problem is similar to the solution described in the above method. Therefore, the specific limitations in one or more embodiments of the following image reconstruction devices can be referred to the limitations on the image reconstruction method in the above text, and will not be repeated here.

[0126] In one embodiment, as Figure 10 shown, an image reconstruction device is provided, including: a determination module, a correction module, and a reconstruction module, where:

[0127] A determination module, configured to determine phase difference information between at least two excitations performed on an object at different times;

[0128] A correction module, configured to correct the imaging data to be corrected obtained through at least two excitations based on the above phase difference information to obtain corrected imaging data; and

[0129] A reconstruction module, configured to obtain a reconstructed image of the object based on the corrected imaging data.

[0130] Optionally, the above device may further include an update module, configured to, when the phase difference information does not meet a preset condition, perform at least one excitation on the object to re-acquire updated imaging data, and update the above phase difference information based on the phase information of the updated imaging data.

[0131] In another embodiment, another image reconstruction device is provided. Based on the above embodiment, the above determination module may include:

[0132] A phase difference map determination unit, configured to determine a phase difference map of excitation images obtained based on at least two excitations based on the phase information corresponding to the at least two excitations; and

[0133] An artifact removal unit, configured to perform artifact removal processing on the phase difference map to obtain phase difference information of a target region corresponding to the object in the excitation images of the at least two excitations.

[0134] Optionally, the above artifact removal unit is specifically configured to obtain a preset mask matching the phase difference map; and remove or reduce the influence of artifact data included in the phase difference map based on the preset mask to obtain the phase difference information.

[0135] In another embodiment, another image reconstruction device is provided. Based on the above embodiment, the above correction module may include:

[0136] A reference image determination unit, configured to determine a reference image in the excitation images obtained based on at least two excitations; and

[0137] A phase correction unit, configured to perform phase correction on other excitation images except the reference image based on the phase difference information to obtain a corrected image whose phase matches the phase of the reference image.

[0138] Optionally, the above phase correction unit is specifically configured to determine a target region corresponding to the object in other excitation images; and perform phase correction on the target region in other excitation images based on the phase difference information to obtain the corrected image.

[0139] In another embodiment, another image reconstruction device is provided. Based on the above embodiment, the reconstruction module may include:

[0140] A fusion unit configured to fuse the imaging data corresponding to the object in the corrected imaging data to obtain fused imaging data; and

[0141] A reconstruction unit configured to obtain a reconstructed image of the object based on the fused imaging data.

[0142] In another embodiment, another image reconstruction device is provided. Based on the above embodiment, the device may further include:

[0143] An acquisition module configured to excite the object under each part of the data space in the same data space to obtain single-shot excitation imaging data corresponding to each part of the data space; and

[0144] An obtaining module configured to obtain the imaging data to be corrected based on the single-shot excitation imaging data corresponding to different parts of the data space in the same data space.

[0145] In one embodiment, a computer device is provided, including a memory and a processor. A computer program is stored in the memory. When the processor executes the computer program, the following steps are implemented:

[0146] Determine the phase difference information between at least two excitations performed on an object at different times; correct the imaging data to be corrected obtained through at least two excitations based on the phase difference information to obtain corrected imaging data; and obtain a reconstructed image of the object based on the corrected imaging data.

[0147] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0148] Determine a phase difference map of the excitation images obtained based on at least two excitations based on the phase information corresponding to at least two excitations; and perform artifact removal processing on the phase difference map to obtain the phase difference information of the target region corresponding to the object in the excitation images of at least two excitations.

[0149] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0150] Obtain a preset mask that matches the phase difference map; and remove or reduce the influence of the artifact data included in the phase difference map based on the preset mask to obtain the phase difference information.

[0151] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0152] In the excitation images obtained based on at least two excitations, determine a reference image; and perform phase correction on the other excitation images except the reference image based on the phase difference information to obtain corrected images whose phases match the phase of the reference image.

[0153] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0154] In the other excitation images, determine a target region corresponding to the object; and perform phase correction on the target region in the other excitation images based on the phase difference information to obtain corrected images.

[0155] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0156] Fuse the imaging data corresponding to the object in the corrected imaging data to obtain fused imaging data; and based on the above fused imaging data, obtain a reconstructed image of the object.

[0157] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0158] In the case where the phase difference information does not meet the preset conditions, perform at least one excitation on the object to re-acquire updated imaging data, and update the above phase difference information based on the phase information of the updated imaging data.

[0159] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0160] Perform excitation on the above object in each part of the data space in the same data space to obtain single-excitation imaging data corresponding to each part of the data space; and based on the single-excitation imaging data corresponding to different parts of the data space in the same data space, obtain the imaging data to be corrected.

[0161] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0162] Determine the phase difference information between at least two excitations performed on the object at different times; based on the above phase difference information, correct the imaging data to be corrected obtained by at least two excitations to obtain corrected imaging data; and based on the corrected imaging data, obtain a reconstructed image of the object.

[0163] In one embodiment, when the computer program is executed by the processor, the following steps are further implemented:

[0164] Determine a phase difference map of the excitation images obtained based on at least two excitations based on the phase information corresponding to at least two excitations; and perform artifact removal processing on the phase difference map to obtain the phase difference information of the target region corresponding to the object in the excitation images of at least two excitations.

[0165] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0166] Obtain a preset mask that matches the phase difference map; and based on the preset mask, remove or reduce the influence of the artifact data included in the phase difference map to obtain the phase difference information.

[0167] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0168] In the excitation images obtained based on at least two excitations, determine a reference image; and based on the phase difference information, perform phase correction on the other excitation images except the reference image to obtain corrected images whose phases match the phase of the reference image.

[0169] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0170] In the other excitation images, determine the target region corresponding to the object; and based on the phase difference information, perform phase correction on the target region in the other excitation images to obtain corrected images.

[0171] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0172] Fuse the imaging data corresponding to the object in the corrected imaging data to obtain fused imaging data; and based on the above fused imaging data, obtain a reconstructed image of the object.

[0173] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0174] In the case where the phase difference information does not meet the preset conditions, perform at least one excitation on the object to re-obtain updated imaging data, and based on the phase information of the updated imaging data, update the above phase difference information.

[0175] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0176] In each part of the data space in the same data space, perform excitation on the above object to obtain single-excitation imaging data corresponding to each part of the data space; and based on the single-excitation imaging data corresponding to different parts of the data space in the above same data space, obtain the imaging data to be corrected.

[0177] In one embodiment, a computer program product is provided, including a computer program which, when executed by a processor, implements the following steps:

[0178] Determine the phase difference information between at least two excitations performed on an object at different times; based on the above phase difference information, correct the to-be-corrected imaging data obtained through at least two excitations to obtain corrected imaging data; and based on the corrected imaging data, obtain a reconstructed image of the object.

[0179] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0180] Based on the phase information corresponding to at least two excitations, determine a phase difference map of the excitation images obtained based on at least two excitations; and perform artifact removal processing on the phase difference map to obtain the phase difference information of the target region corresponding to the object in the excitation images obtained through at least two excitations.

[0181] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0182] Obtain a preset mask that matches the phase difference map; and based on the preset mask, remove or reduce the influence of the artifact data included in the phase difference map to obtain the phase difference information.

[0183] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0184] In the excitation images obtained based on at least two excitations, determine a reference image; and based on the phase difference information, perform phase correction on the other excitation images except the reference image to obtain corrected images whose phases match the phase of the reference image.

[0185] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0186] In the other excitation images, determine the target region corresponding to the object; and based on the phase difference information, perform phase correction on the target region in the other excitation images to obtain corrected images.

[0187] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0188] Fuse the imaging data corresponding to the object in the corrected imaging data to obtain fused imaging data; and based on the above fused imaging data, obtain a reconstructed image of the object.

[0189] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0190] When the phase difference information does not meet the preset conditions, at least one excitation is performed on the object to re-acquire the updated imaging data, and the above phase difference information is updated based on the phase information of the updated imaging data.

[0191] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0192] In each part of the data space in the same data space, the object is excited to obtain the single-excitation imaging data corresponding to each part of the data space; and based on the single-excitation imaging data corresponding to different parts of the same data space, the imaging data to be corrected is obtained.

[0193] It should be noted that the data involved in this application (including but not limited to the data for analysis, stored data, displayed data, etc.) are all data fully authorized by all parties, and the collection, use, and processing of the relevant data need to comply with the relevant regulations.

[0194] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided in the present application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided in the present application can be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0195] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0196] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. An image reconstruction method, characterized in that: include: determining phase difference information between at least two excitations performed on the object at different times; Based on the phase difference information, correcting the imaging data to be corrected obtained by the at least two excitations to obtain corrected imaging data; and Based on the corrected imaging data, a reconstructed image of the object is obtained.

2. The image reconstruction method according to claim 1, characterized in that: The determining of phase difference information between at least two excitations performed on the object at different times comprises: Determining a phase difference map of an excitation image obtained based on the at least two excitations based on phase information corresponding to the at least two excitations; and The phase difference image is subjected to artifact removal processing to obtain phase difference information of a target area corresponding to the object in the excitation images of the at least two excitations.

3. The image reconstruction method according to claim 2, characterized in that: The performing artifact removal processing on the phase difference image to obtain phase difference information of a target area corresponding to the object in the excitation images of the at least two excitations includes: Acquiring a preset mask matching the phase difference map; and The phase difference information is obtained by removing or reducing the influence of the artifact data included in the phase difference map based on the preset mask.

4. The image reconstruction method according to claim 1, characterized in that: The method of correcting the imaging data to be corrected obtained by the at least two excitations based on the phase difference information to obtain the corrected imaging data comprises: Determining a reference image among the excitation images obtained based on the at least two excitations; and Phase correction is performed on other excitation images except the reference image based on the phase difference information to obtain a corrected image whose phase matches that of the reference image.

5. The image reconstruction method according to claim 4, characterized in that: The step of performing phase correction on other excitation images except the reference image based on the phase difference information to obtain a corrected image whose phase matches that of the reference image comprises: determining a target area corresponding to the object in the other excitation images; and Based on the phase difference information, phase correction is performed on the target area in the other excitation image to obtain the corrected image.

6. The image reconstruction method according to claim 1, characterized in that: The step of obtaining a reconstructed image of the object based on the corrected imaging data comprises: fusing the imaging data corresponding to the object in the corrected imaging data to obtain fused imaging data; and Based on the fused imaging data, a reconstructed image of the object is obtained.

7. The image reconstruction method according to claim 1, characterized in that: After determining the phase difference information between at least two excitations performed on the object at different times, the method further includes: In a case where the phase difference information does not satisfy a preset condition, updated imaging data is reacquired by performing at least one excitation on the object, and the phase difference information is updated based on phase information of the updated imaging data.

8. The image reconstruction method according to claim 1, characterized in that: The method further comprises: In each part of the data space in the same data space, the object is excited to obtain single excitation imaging data corresponding to each part of the data space; and The imaging data to be corrected is obtained based on the single-shot imaging data corresponding to different parts of the data space in the same data space.

9. An image reconstruction device, characterized in that: The device comprises: A determination module, configured to determine phase difference information between at least two excitations performed on the object at different times; a correction module, configured to correct the imaging data to be corrected obtained by the at least two excitations based on the phase difference information to obtain corrected imaging data; and A reconstruction module is used to obtain a reconstructed image of the object based on the corrected imaging data.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the image reconstruction method according to any one of claims 1 to 8 are implemented.

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