CN103190927A - Method and system for determining motion field and generating motion-compensating CT image data sets - Google Patents
Method and system for determining motion field and generating motion-compensating CT image data sets Download PDFInfo
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Abstract
The method relates to a method, a calculating system and a CT system for determining a motion field and generating motion-compensating CT image data sets of a partially moving object. It is suggested that the motion field is preferably and iteratively determined by using the only projection data in the CT image data sets and the extreme value of at least one image feature found in a motion-compensating reconstructed tomographic image data sets, and the ultimate CT diagram form is generated through reconstruction in a motion-compensating manner through the determined motion field and used projection data sets.
Description
Technical field
The present invention relates to a kind ofly for determining the method for sports ground in the CT image data set of the object of motion partly, this sports ground is by forming specific to the motion vector of position in a large number.The invention still further relates to a kind of for generation of the method for the CT image data set of the motion of objects compensation of motion partly.In addition, the invention still further relates to a kind of computing system for image reconstruction and a kind of CT system with such computing system, wherein when operation, implement above-mentioned method.
Background technology
Be well known that generally because the heart movement during CT takes, captured data are inconsistent and cause image artifacts, its strong restrictions the clinical availability of data.For fear of this image artifacts, the demonstration of being correlated with the stage that in modern CT cardiac imaging, produces heart by shooting or the use data relevant with heart phase.Basically there are that recall and acquisition scheme prediction for this reason.Under the situation of acquisition scheme of prediction, near the certain window photographed data the quiescent phase of heart and be used for image reconstruction only.The common purpose of these schemes is heart movement almost to be freezed and minimise data is inconsistent and make picture quality the best thus.
But because rotating or rotate the too fast following strategy of heart beating with respect to frame, the frame slow excessively with respect to heart movement be not enough to realize enough good temporal resolution, to calculate artifact-free image.Known different from the algorithm that improves temporal resolution afterwards in the prior art.
At H.
The document of T.Allmendinger, K.Stierstorfer, H.Bruder and T.Flohr " Evaluation of a novel CT image reconstruction algorithm with enhanced temporal resolution ", Proceedings of SPIE, p.79611N, the theoretic angle scanning of having described in 2011 by being lower than 180 degree reduces required data volume, wherein must optimize picture quality iteratively owing to incomplete data.
In addition, at D.
The document of J.Borgert, V. Rasche and M. Grass " Motion-Compensated and Gated Cone Beam Filtered Back-Projection fbr 3-D Rotational X-Ray Angiography ", IEEE Transactions on Medical Imaging, Vol.25, No.7, pp.898-906 discloses in 2006 7 months to may be thought of as during motion compensated reconstruction under the situation of known object motion and has rebuild employed data.This process causes greatly having improved picture quality.
In order to improve " optimal state " image quality in images, the just image that obtains from the quiescent phase of the best and first water thus correctly estimate that the problem of motion does not also solve but up to now.Scheme is so far only estimated motion by two three-dimensional standard reconstruction of the different heart phase of registration.But the quality improvement that can not show " optimal state " image so far is because this image has limited the temporal resolution of the data of registration inherently.On the contrary, greatly improved the image of relatively poor heart phase and for example can show other heart phase with the picture quality of improving thus.
Summary of the invention
Therefore, the technical problem to be solved in the present invention is, find a kind of method for image reconstruction and a kind of CT system or a kind of computing system, its (determine the motion of heart or be identified for the sports ground of image correcting data subsequently with improving by improvement ground) reduced remaining image artifacts.
Basis of the present invention is to express estimation by the algorithm for reconstructing of motion compensation with improving.Correspondingly, to " optimal state " image f
Bp(x, s) result who carries out the reconstruction of motion compensation directly depends on the parameter of describing motion
Such estimated parameter s makes the result satisfy specific characteristics of image for this reason.This can pass through cost function in form
Minimize to realize as assay measures.
If use the algorithm for reconstructing of resolving in order to rebuild " optimal state " image, FDK algorithm (FDK=Feldkamp-Davis-Kress) for example, then can provide effective calculating standard, this calculating standard for example is identified for the parameter of the reconstruction of motion compensation iteratively by gradient decline.In addition, can only come calculating target function by the parts of images that comprises motion in order to reduce computing cost.In form, calculate motion diagram (Bewegungskarte), there is the probability of motion artifacts in this motion diagram explanation in this position in image for this reason.
Substantially conceive corresponding to this, the inventor also advises following method and apparatus:
Taproot of the present invention is by being used for partly determining that with the CT image data set of the object that may move periodically (particularly having the dirty patient of pulsatile heart) method of sports ground forms, wherein this sports ground is by a large amount of kinematic parameters, particularly form specific to the motion vector of position, should describe object about the motion of time period of taking specific to the motion vector of position, and this method has following method step:
-gather or transmit the projection data set of computer-tomographic system, comprise motion stage given in advance and projection angle zone, described projection data set allows directly to rebuild the CT image data set,
-use the first analytic reconstruction algorithm and repeatedly rebuilding the CT image data set with first image resolution ratio by the method for reconstructing of motion compensation under the situation by a large amount of kinematic parameters, the different sports ground particularly formed specific to the motion vector of position respectively
-determine sports ground, at least one characteristics of image has extreme value in the reconstruction in motion compensation under the situation of using this sports ground,
-storage and/or output movement field.
Namely, in the above in the method for Miao Shuing (unlike the prior art) be not by two or more image data set relatively come to determine the motion, but only use to rebuilding the data for projection that unique three-dimensional image data sets is made contributions, thereby determine the kinematic parameter about the sports ground of the resolution of shooting time or heart phase, method is to find such kinematic parameter, it finally (is namely rebuild by the reconstruction of motion compensation, under the situation of described reconstruction use under the condition of sports ground and for compensation describe there specific to the position with specific to the diagram of the motion calculation tomography of time) cause the image of such reconstruction, optimize the characteristics of image of tolerance of the motion blur of one or more presentation videos in the image of this reconstruction as follows, making can be from the motion blur of minimum.
In order to produce distinct image as far as possible from the beginning, what have advantage is that projection angle zone (detector data stems from this projected angle zone) is 180 ° and adds to scanning the fan-shaped angle of employed beam.This can carry out the shooting of tomography corresponding to the projection angle zone of minimum by this projection angle zone in conventional reconstruction technique.
Suggestion in addition makes with the following method motion compensated schemes as the method for reconstructing of resolving: FDK method for reconstructing (FDK=Feldmann-Davis-Kress), Clack-Defrise method for reconstructing, based on the method for reconstructing of Hilbert transform, based on the method for reconstructing of Fourier transformation, based on the method for reconstructing of back projection.
For example can use one or more following characteristics of image as optimisation criteria that be used for to determine sports ground: entropy, gradient and, total variance/total fluctuation, compressibility, with similarity or the iconic model of reference picture.
In addition advantageously, in order to carry out according to method of the present invention, as common in the cardiac reconstruction, collect detector data with for generation of employed projection data set from a plurality of periods of motion (under the condition of assumption period motion).At this, for example pass through repeatedly heart beating and collect detector data from (may be narrow) predetermined phase zone respectively, up to the required projection angle zone of scanning, thereby thus owing to presented as far as possible little motion blur for rebuilding employed detector data, but this motion blur is by further being reduced according to method of the present invention.
In addition advantageously, use a plurality of x-ray sources (double source) for carrying out according to method of the present invention.At this, about just in time identical time point but different angle shot data has greatly reduced the shooting of whole angular range thus and improved temporal resolution thus, but this temporal resolution is by further reducing according to method of the present invention.
What have advantage in addition is not to be to use the illustrated whole zone of tomography to determine sports ground, but only to calculate sports ground about the subregion of object.Can reduce required rated output on the one hand thus, and can be restricted to actual relevant zone on the other hand, not produce interference thereby be in outside pseudo-shadow.
Also advise a kind ofly for generation of the method for the CT image data set of the motion compensation of the object (particularly having the dirty patient of pulsatile heart) of motion periodically partly and particularly now for the method for determining sports ground based on previously described, this method has following method step:
-gather or transmit the projection data set of computer-tomographic system, comprise motion stage given in advance and projection angle zone, described projection data set allows directly to rebuild the CT image data set,
-determine sports ground according to the present invention,
-under the situation of the method for reconstructing that uses motion compensation, rebuild the final CT image data set with second image resolution ratio based on second algorithm for reconstructing and sports ground,
The final CT image data set of-storage or final CT image data set exported at image reproducing system.
Thus, carry out the reconstruction calculating of motion compensation and the diagram of computed tomography radiography based on the sports ground of determining according to the present invention, in this diagram, remove motion artifacts at least as much as possible.In a word, based on the tomography diagram that " optimal state " detector data is improved again, use other detector data and need not to exceed for rebuilding the detector data that illustrates original needs for this reason.
Though in principle when calculating sports ground and can be based on identical position resolution when calculating final image, but be that (be used for calculate sports ground) first image resolution ratio is lower than (final CT is illustrated) second image resolution ratio owing to what the reason of computation time had advantage.
In addition advantageously, second algorithm for reconstructing is different with first algorithm for reconstructing.For example can use simple relatively analytical algorithm in the scope of determining sports ground thus, it allows to rebuild as far as possible fast, and the algorithm of trouble that produces optimized image is used in illustrated final reconstruction for CT.
It should be appreciated that, in the scope of determining sports ground, not necessarily must only use unique algorithm for reconstructing.Also can be at first determine sports ground roughly by the reconstruction of simple " roughly " extremely, and using " the finely tuning (Finetuning) " of carrying out sports ground under the situation of the method for reconstructing of trouble then.
First algorithm for reconstructing must be the algorithm for reconstructing of resolving, and second algorithm for reconstructing can be that resolve, iteration or the algorithm for reconstructing of the motion compensation of statistics, wherein goes back the image enhancement afterwards of application of known within the scope of the invention.
In addition, can collect detector datas from one or more periods of motion, with for generation of employed projection data set.
Except according to method of the present invention, the inventor also advises a kind of computing system for image reconstruction, this computing system has for the memorizer of storage computer program with for the processor of carrying out the computer program of storing, wherein stored at least one computer program in memorizer, this computer program is carried out the method step according to method of the present invention when computing system moves.
A kind of have the CT system of previously described computing system, particularly double source CT system and also belong to scope of the present invention.
Description of drawings
By accompanying drawing the present invention and preferred embodiment are described further below, wherein only are depicted as and understand feature required for the present invention.Use following Reference numeral: 1:CT system/C C-arm system C; 2: the first X-ray tubes; 3: the first detectors; 4: the second X-ray tubes; Detector 6 in 5: the second: the frame housing; 7: turning arm; 8: check bed; 9: system's axle; 10: computing system; 11: the contrast agent applicator; The 12:EKG lead; P: patient; Prg
1-Prg
n: computer program.In the accompanying drawing:
Fig. 1 shows for the CT system that carries out according to method of the present invention;
Fig. 2 shows for the C C-arm system C of carrying out according to method of the present invention;
Fig. 3 shows the CT cross-sectional image of the tomography of the heart that is obtained by the double source CT inspection;
Fig. 4 shows the CT cross-sectional image of the tomography of the heart that is obtained by single source CT examination;
Fig. 5 shows the CT cross-sectional image of rebuilding the tomography of the heart that is obtained by single source CT examination under situation about using according to the reconstruction of motion compensation of the present invention.
The specific embodiment
Fig. 1 illustrates the CT system 1 with computing system 10, utilizes this computing system 10 can implement according to method of the present invention.CT system 1 has the first pipe/detector system of the detector 3 that has X-ray tube 2 and positioned opposite.Alternatively, this CT system 1 has the detector 5 of second X-ray tube 4 and positioned opposite.Two pipe/detector systems are positioned on the frame, and this frame is arranged in the frame housing 6 and in scan period rotates around system's axle 9.Patient P is positioned at and movably checks on the bed 8, this inspection bed or move through the scanning field that is arranged in frame housing 6 along z axle or system's axle 9 continuously or sequentially, the wherein decay of the X-radiation that sends from X-ray tube by detector measurement.
Can be by contrast agent applicator 11 to patient P injection of contrast medium piece (Kontrastmittelbolus) during measuring, thus can identify blood vessel better or can carry out perfusion and measure.In heart is taken, can additionally measure cardiomotility and carry out the scanning of EKG gate by EKG lead 12.
Control the CT system and carry out according to method of the present invention computer program Prg by computing unit 10
1-Prg
nBe arranged in this computing unit 10, these computer programs also can be carried out previously described according to method of the present invention.Additionally also can pass through these computing unit 10 output image datas.
Alternatively also can be in conjunction with according to C C-arm system C 1(as shown in Figure 2) detector data of the CT system of type carries out according to method of the present invention.The detector 3 that has the planar configuration of X-ray tube 2 and positioned opposite at the C C-arm system C 1 shown in this equally.Two systems rotate around patient P with the optional position by turning arm 7.At this, patient P is positioned on patient's bed 8, and this patient's bed additionally has contrast agent application system 11, so that the injection of contrast medium in order to show blood vessel in case of necessity.In addition, the EKG that also can not be shown specifically in this C C-arm system C scans to be used for determining cardiac cycle and the phase of the cycles that embeds therein.
Equally, by in its memorizer, having computer program Prg
1-Prg
nComputing unit 10 come control system, this computer program also can be carried out according to method of the present invention be used for determining sports ground inter alia, and can implement the reconstruction of motion compensation of the best of the view data of tomography by this sports ground.
As has been describ, to image f
Bp(x, s) result who carries out the reconstruction of motion compensation directly depends on the parameter of describing motion
According to definite these parameter s corresponding to motion vector of the present invention, method is to optimize and utilize these parameters to carry out the characteristics of image of the image of motion compensation ground reconstruction.This point for example can be passed through cost function based on the image data set of utilizing the different motion field to rebuild in a large number
Minimize to realize as assay measures, wherein change sports ground always and reach best up to cost function.
Thus, can provide effective calculating standard, this calculating standard is identified for the parameter s of the reconstruction of motion compensation iteratively by one or more characteristics of image (for example gradient decline) for this reason, uses the algorithm for reconstructing of resolving in order to rebuild.In addition for the computing cost that reduces sports ground also can be only the parts of images of relevant motion by comprising expection calculate sports ground.
In order to determine that sports ground can use motion model.This motion model M:
Based on parameter s for the shooting time of i projection calculate at home position x place physical location x '=M (i, x, s).The example that is used for motion model is intensive sports ground.There is mobile vector for each the position y in j projected image
Formula is namely:
M (i, x, s)=x+s
I, x=x '. formula (1)
But also can use other sparse sports ground (for example being formed by the B batten) or other linear basic function within the scope of the invention, and non-linear basic function, NURBS (=Non-Uniform Rational B-Spline, non-homogeneous B spline curve) for example.
Can be referring to the FDK algorithm for reconstructing of known motion compensation as the concrete example for the algorithm for reconstructing of motion compensation, this FDK algorithm for reconstructing has been quoted in front
Open in the document of et al..This FDK algorithm is a kind of in the conventional algorithm that uses in the Clinical CT.The formula f of back projection below it can pass through on mathematics:
Describe:
Function
The projection value p of the convolution of i the projected image at permission visit detector position u place (i, u).Function A:
In i projected image, 3-D view position x is mapped to two-dimensional detector position u=A (i, x).At this, accurate formula depends on employed system geometric properties.Function Q:
It is the weighting function for the correction data redundancy.Accurate formula depends on system's geometric properties and screening-mode again.
The key components of this scheme are the suitable cost functions of definition.Show that in the literature for example the compactedness of image or compressibility are represented the suitable tolerance for the pseudo-shadow of images acquired.Example for this reason is entropy, for example based on compressible general tolerance or TV (Total Variation, the total variance) norm of cosine transform or wavelet transformation.
As specific embodiment, provide entropy here, utilize its following given price value function:
P wherein:
Be given in the image f that CT rebuilds (x, s) in the Hao Ensi Felder be unit (Hounsfield-Einheit) image value, be the probability of CT value h ∈ HU appearance.At this, can or also can be only in the image section zone Ω definite by motion diagram (face as follows), calculate desired value by total image.For example can bear window density Estimation method by group
Determine probability function, its following providing with resolving:
Window density Estimation method is born based on kernel function K by group, gaussian kernel (Gau β kern) for example, for its establishment:
At this, the smoothness of density function P has been determined in standard deviation＞0.
By motion diagram (motion map) can be with sports ground determine only to be confined to the pith zone of the actual displayed motion artifacts of image according to the present invention.The subclass of all possible picture position by calculating being confined to entire image realizes this point particularly.The coupling of this picture position directly is reflected in the computing formula.By the picture quality of using this motion diagram can reduce computation time, improve the sensitivity of image metric and can realize thus improving.At this, motion diagram has been described the subclass Ω of image volume to be rebuild.
Be used for determining that with following two the scheme of motion diagram is example:
Two adjacent reconstructions relevant with the stage of-calculating.Set omega is all pixels that absolute difference surpasses threshold value.
Two adjacent reconstructions relevant with the stage of-calculating.Carry out the 3D/3D registration.Set omega is all that pixel that motion vector surpasses threshold value.
According to the present invention, carry out estimation by optimizing algorithm, just determine the sports ground of forming specific to motion vector or the mobile vector of position by in a large number.Find out parameter at this
This parameter is found out cost function with minimizing
Namely set up:
Formula (7)
Definition for this optimization problem, can use graphics standard or characteristics of image arbitrarily, such as the compressibility of entropy, total variance or the view data of reconstructed image, the minimizing or maximize of wherein one or more characteristics of image shows the best sports ground of determining.The parsing derivative of all components that provide (namely rebuilding and analytic function) can be provided for quick and stable calculating.By using optimization method, solve the optimization problem of such expression such as gradient descent method, Newton method, random optimization method, evolutionary optimization method or the method for exhaustion.
For preferred specific the solution, within the scope of the invention also can be to adjust item
Replenish optimization problem.This can the preferred movement field special characteristic.This mention for example motion vector length and.At this, each motion causes the adjusted value that improves, but wherein graphical analysis tolerance becomes littler.Weight according to two items finds the solution that can optimize image metric and adjust item now.Thus, on the mathematics for example can by add the item following characterising parameter:
The method of advising thus, has realized improving " optimal state " first by estimation and motion compensation and has rebuild.In addition, the method for advising is used to improve other motion or heart phase, perhaps is used to reduce noise or better dose application.The high sensitivity of the method that provides is provided by motion diagram and calculates fast, because it is important and can use at clinical field thus to calculate institute fast.
In Fig. 3 to Fig. 5, show the minimizing of the motion blur of " optimal state " image according to the CT cross-sectional image of cardiac work up.Fig. 3 shows by " optimal state " cross-sectional image photo of rebuilding the heart that draws based on the routine of double source CT scanning.Fig. 4 shows identical cross section, but is drawn by the data reconstruction that utilizes single source CT scan.Fig. 5 shows identical cross section again, is rebuild by the data of utilizing single source CT scan equally to draw, but rebuilds under the condition of using according to method of the present invention.All detector datas are derived from 74% the heart phase in cycle.As can be seen, it is minimum to take in (Fig. 3) motion blur at double source, and temporal resolution is not enough to not be illustrated in the coronary artery at arrow place with having pseudo-shadow in single source shooting (Fig. 4) that routine is rebuild.But by to using according to method of the present invention with employed identical detector data group in Fig. 4, can obviously reduce motion artifacts, thereby also draw almost artifact-free diagram according to Fig. 5 by single source data.
In a word, data for projection by using unique CT image data set of the present invention suggestion, by finding the extreme value of at least one characteristics of image in the tomography data group of rebuilding on motion compensation ground, preferably determine sports ground iteratively, and produce final CT by the sports ground determined like this and already used projection data set, reconstruction by motion compensation and illustrate.
Although, the invention is not restricted to disclosed example and can therefrom derive other scheme by the professional, and do not break away from protection scope of the present invention the detailed description of the invention and description by preferred embodiment.
Claims (16)
1. method that is used for determining in the CT image data set that partly with the object that may move periodically, particularly has a dirty patient of pulsatile heart (P) sports ground, described sports ground is by forming specific to the position with specific to the motion vector of time in a large number, and described method has following method step:
1.1. gather or transmit the projection data set of computer-tomographic system (1), comprise motion stage given in advance and projection angle zone, described projection data set allows directly to rebuild CT image data set (=180 °+probe angle),
1.2. use the first analytic reconstruction algorithm with respectively by under the situation of position and the different sports ground of forming specific to the motion vector of time, repeatedly rebuilding the CT image data set with first image resolution ratio by the method for reconstructing of motion compensation in a large number,
1.3. determine sports ground, at least one characteristics of image has extreme value in the reconstruction in motion compensation under the situation of using this sports ground,
1.4. store and/or export described sports ground.
2. require 1 described method according to aforesaid right, it is characterized in that, described projection angle zone is 180 ° of fan-shaped angles that add employed beam.
3. require 1 or 2 described methods according to aforesaid right, it is characterized in that the method for reconstructing of described parsing is one of method in the following tabulation:
-FDK method for reconstructing (FDK=Feldmann-Davis-Kress),
-Clack-Defrise method for reconstructing,
-based on the method for reconstructing of Hilbert transform,
-based on the method for reconstructing of Fourier transformation,
-based on the method for reconstructing of back projection.
4. require each described method in 1 to 2 according to aforesaid right, it is characterized in that, use characteristics of image at least one following tabulation as characteristics of image to be optimized:
-entropy,
-gradient and,
-total variance/total fluctuation,
-compressibility,
-with the similarity of other reference picture.
5. require each described method in 1 to 4 according to aforesaid right, it is characterized in that, collect described detector data with for generation of employed projection data set from a plurality of periods of motion.
6. require each described method in 1 to 5 according to aforesaid right, it is characterized in that, only calculate described sports ground about the subregion of object.
One kind for generation of partly with the object that may move periodically, particularly have the method for CT image data set of the dirty patient's of pulsatile heart (P) motion compensation, this method has following method step:
7.1. gather or transmit the projection data set of computer-tomographic system (1), comprise motion stage given in advance and projection angle zone, described projection data set allows directly to rebuild the CT image data set,
7.2. according to each determines sports ground in the claim 1 to 4,
7.3. under the situation of the method for reconstructing that uses motion compensation, rebuild the final CT image data set with second image resolution ratio based on second algorithm for reconstructing and sports ground,
7.4. store described final CT image data set or described final CT image data set exported at image reproducing system.
8. require 7 described methods according to aforesaid right, it is characterized in that, described first image resolution ratio is lower than described second image resolution ratio.
9. require each described method in 7 to 8 according to aforesaid right, it is characterized in that described second algorithm for reconstructing is different with described first algorithm for reconstructing.
10. require 9 described methods according to aforesaid right, it is characterized in that, described second algorithm for reconstructing is the algorithm for reconstructing of resolving.
11. require 9 described methods according to aforesaid right, it is characterized in that described second algorithm for reconstructing is the algorithm for reconstructing of iteration.
12. require 9 described methods according to aforesaid right, it is characterized in that described second algorithm for reconstructing is algorithm for reconstructing iteration or statistics.
13. require each described method in 1 to 12 according to aforesaid right, it is characterized in that, collect described detector data with for generation of employed projection data set from a plurality of periods of motion.
14. require each described method in 1 to 13 according to aforesaid right, it is characterized in that, collect described detector data with for generation of employed projection data set from a plurality of x-ray sources.
15. computing system (10) that is used for image reconstruction, described computing system has for the memorizer of storage computer program with for the processor of carrying out the computer program of storing, it is characterized in that, in memorizer, stored at least one computer program (Prg
1-Prg
n), described computer program is carried out according to the method described above each described method step in the claim when computing system (10) moves.
16. a CT system (1), particularly double source CT system have according to aforesaid right requirement 15 described computing systems (10).
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| DE102011083646.2 | 2011-09-28 | ||
| DE201110083646 DE102011083646A1 (en) | 2011-09-28 | 2011-09-28 | Method for determination of motion field of heart of patient, involves determining motion field using extreme value of image based on motion-compensating reconstructed tomographic image data sets |
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| CN103190927A true CN103190927A (en) | 2013-07-10 |
| CN103190927B CN103190927B (en) | 2016-07-06 |
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| CN201210363885.2A Active CN103190927B (en) | 2011-09-28 | 2012-09-26 | Determine the method and system of the CT image data set of sports ground and generation motion compensation |
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| DE (1) | DE102011083646A1 (en) |
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| CN104424659A (en) * | 2013-08-30 | 2015-03-18 | 西门子公司 | Image-based motion compensation of image data |
| CN105303589A (en) * | 2014-10-21 | 2016-02-03 | 沈阳东软医疗系统有限公司 | Method and device for calculating motion vector field in reconstructed image of CT scanning |
| CN105849778A (en) * | 2013-12-20 | 2016-08-10 | 皇家飞利浦有限公司 | Moving structure motion compensation in imaging |
| WO2017205379A3 (en) * | 2016-05-23 | 2018-07-19 | Rensselaer Polytechnic Institute | Image reconstruction method for computed tomography |
| CN108338802A (en) * | 2017-01-10 | 2018-07-31 | 西门子医疗有限公司 | Method for reducing image artifacts |
| CN111093506A (en) * | 2017-07-27 | 2020-05-01 | 皇家飞利浦有限公司 | Motion compensated heart valve reconstruction |
| CN113424227A (en) * | 2019-01-11 | 2021-09-21 | 中佛罗里达大学研究基金会公司 | Motion estimation and compensation in Cone Beam Computed Tomography (CBCT) |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104424659A (en) * | 2013-08-30 | 2015-03-18 | 西门子公司 | Image-based motion compensation of image data |
| US9619869B2 (en) | 2013-08-30 | 2017-04-11 | Siemens Aktiengesellschaft | Image-based motion compensation of image data |
| CN105849778A (en) * | 2013-12-20 | 2016-08-10 | 皇家飞利浦有限公司 | Moving structure motion compensation in imaging |
| CN105303589A (en) * | 2014-10-21 | 2016-02-03 | 沈阳东软医疗系统有限公司 | Method and device for calculating motion vector field in reconstructed image of CT scanning |
| CN105303589B (en) * | 2014-10-21 | 2018-06-26 | 沈阳东软医疗系统有限公司 | For calculating the method and device of the motion vector field in the reconstruction image of CT scan |
| WO2017205379A3 (en) * | 2016-05-23 | 2018-07-19 | Rensselaer Polytechnic Institute | Image reconstruction method for computed tomography |
| CN108338802A (en) * | 2017-01-10 | 2018-07-31 | 西门子医疗有限公司 | Method for reducing image artifacts |
| CN108338802B (en) * | 2017-01-10 | 2019-07-12 | 西门子医疗有限公司 | Method for reducing image artifacts |
| CN111093506A (en) * | 2017-07-27 | 2020-05-01 | 皇家飞利浦有限公司 | Motion compensated heart valve reconstruction |
| CN111093506B (en) * | 2017-07-27 | 2023-08-01 | 皇家飞利浦有限公司 | Motion compensated heart valve reconstruction |
| CN113424227A (en) * | 2019-01-11 | 2021-09-21 | 中佛罗里达大学研究基金会公司 | Motion estimation and compensation in Cone Beam Computed Tomography (CBCT) |
| CN113424227B (en) * | 2019-01-11 | 2023-07-25 | 中佛罗里达大学研究基金会公司 | Motion estimation and compensation in Cone Beam Computed Tomography (CBCT) |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103190927B (en) | 2016-07-06 |
| DE102011083646A1 (en) | 2013-03-28 |
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