CN101512379B - Acquisition and reconstruction of projection data using a stationary ct geometry - Google Patents
Acquisition and reconstruction of projection data using a stationary ct geometry Download PDFInfo
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- CN101512379B CN101512379B CN200780032561.8A CN200780032561A CN101512379B CN 101512379 B CN101512379 B CN 101512379B CN 200780032561 A CN200780032561 A CN 200780032561A CN 101512379 B CN101512379 B CN 101512379B
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Abstract
Systems and methods are provided for acquiring and reconstructing projection data that is mathematically complete or sufficient acquired using a computed tomography (CT) system. In one embodiment, a distributed source is provided as arcuate segments offset in the X-Y plane and along the Z-axis. In another embodiment, a set of projection data representative of a sampled portion of a cylindrical surface is provided. The set of projection data is reconstructed using a suitable cone-beam reconstruction algorithm. In another embodiment, two or more sets of spatially interleaved helical projection data are processed using helical interpolation. The helically interpolated set of projection data is reconstructed using a two-dimensional axial reconstruction algorithm or a three-dimensional reconstruction algorithm.
Description
The cross reference of related application
The name that the application requires to submit on August 30th, 2006 is called the U.S. Provisional Patent Application No.60/841 of " using collection and the reproduction of the geometric data for projection of static CT ", 010 right of priority, and it all is merged in by reference at this.
Technical field
The present invention relates generally to the imaging system of computer topography (CT) (CT), and exactly, the source and the detector arrangement that relate to static CT system are used for image reproducing so that measure data for projection complete most.
Background technology
The CT projected dataset comprises from respect to the patient of imaging or X-ray tube and the position, numerous angle of detecting device or the projection measurement data at visual angle of object.On one group of mathematics, complete data for projection is included in and is enough to be rendered as the measurement data of image space (imagingvolume) without human factor in the constraint of data acquisition system (DAS).Mathematical incomplete meeting results from lacking the disappearance data for projection in projection, a part of image fully or selecting inappropriate how much imaging parameters for example to pass the patient of stand (gantry) or the speed of object under the helical acquisition pattern of data for projection.Importantly complete on described data for projection mathematics, otherwise, can not be with the needed fidelity reproduced image of application-specific data.
CT is a kind of technology of setting up the three-dimensional image of two-dimensional cross sectional image or three-dimensional structure.This x-ray tomography shadowgraph technique is for example controlled for safety examination, luggage and baggage inspection, workmanship by noninvasive imaging and medical assessment is useful especially.
Traditional CT imaging system can comprise the CT stand and the imaging space that is used for movement of objects is limited by the X-ray collimator in the described stand in order to be scanned or be moved out of in this imaging space.In this system, described stand is generally framework movably, and this framework comprises X-ray source, and it is generally the collimating apparatus that is included on the one side and the X-ray tube of wave filter; And the detecting device on opposite side, this detecting device has relevant data acquisition system (DAS) (DAS).Described stand generally also comprises the rotary part that needs slip ring system and the electronic equipment that all are relevant, for example stand angle measurement motor and locating laser.
For example, in so-called " third generation " CT system, X-ray source becomes fixed sturcture with described detector array, and this fixed sturcture is to be rotated in imaging plane and around the object that will be imaged by stand, so that the angle that X-ray and described object intersect changes consistently.X-ray detector comprises crystal or ionized gas, and this γ-ray emission can be detected and collect light or the electric energy for generation of predetermined image when being collided by the X-ray photons.This rotation CT system has restriction at the mechanical equilibrium of rotational speed, system and electricity and heat condition, because these conditions of needs rotation compliant member become day by day complicated.In addition, these restrictions have restricted the possible rotational speed of described stand, make this rotary system be not suitable for requiring in the application of temporal resolution and high-throughput preferably.
The CT structure of other types is not rotated, and is namely static, and comprises the structure that high sweep velocity is provided.For example, in a so static CT system, X-ray source and detecting device are all static and are surrounded as the image space.In this system, X-ray source can be the distribution X-ray source, comprises a plurality of discrete electronic emitter and distributed anode along its length.
Since X-ray source and detecting device are all static in this static CT structure, they need to be designed to so that suitable scan protocols.For example, in a possible axial scan structure, the distribution X-ray of two longitudinal lengths of the detecting device that is positioned at the center can with respect to area detector array a little (vertically and/or radially) depart from.As a result, the X-ray can not stood in space (volume) intracardiac in the visual field of imaging system, stops to reproduce in this space.Similarly, in the spiral scan structure, the distribution X-ray source can be placed on around between two area detectors of whole imaging space.The X-ray passes two gaps between detector array so that the X-ray flux is transmitted into described imaging space.Because X-ray source also is distributed on entering around the hole of described stand, the whole imaging space of described gap encircles, it prevents the measurement of CT data for projection complete on mathematics and the non-artificial image reproducing in described space.For example, for helical acquisition, each reproduces the data for projection that section has some disappearances.As a result, the data for projection of collection is incomplete on mathematics.
Therefore be desirable to provide a kind of improved source for static CT system and the data acquisition protocol of detector arrangement or modification, in order to measure the appropriate algorithm of the rendering data that is used for data more complete on the mathematics of image reproducing and is provided for gathering by this technology.
Summary of the invention
A kind of method for gathering two or more sets data for projection is provided.The method comprises the behavior of a plurality of addressable X-ray sources position of triggering annular source, makes each X-ray source position emission X-ray when being triggered.Each signal at detector array place is generated as each the corresponding triggering corresponding to the X-ray source position.Each corresponding signal is corresponding to the X-ray that incides described detector array and list.Each total signal is corresponding to helical scan data staggered on two or more sets space.Corresponding claim also is provided, has related to appreciable machine readable medium, this medium comprises the code that can carry out to carry out these actions.
A kind of method of the data for projection for gathering two or more sets is provided.The method comprise a plurality of X-ray sources position of triggering annular source behavior so that when being triggered each X-ray source position emission X-ray.A plurality of X-ray sources position is triggered disorderly.Each signal at detector array place is generated as each the corresponding triggering corresponding to the X-ray source position.Each corresponding signal is corresponding to the X-ray that incides described detector array and list.Corresponding claim also is provided, has related to appreciable machine readable medium, this medium comprises the code that can carry out to carry out these actions.
A kind of imaging system is provided.This imaging system comprises the detector array that contains a plurality of detecting elements, and wherein said detecting element is configured to produce the signal corresponding with inciding X-ray that described detector array lists.This imaging system also comprises the annular source in the gap that is arranged in detector array.This annular source comprises a plurality of X-ray sources position that is configured to unordered triggering.When being triggered, each X-ray source position emission X-ray.
A kind of imaging system is provided.This imaging system comprises detector array and the gap area that contains a plurality of detecting elements.This imaging system also comprises the source that is arranged in this gap area.This source comprises a plurality of X-ray sources positions.This source tilts with respect to the axle of the imaging system that is limited by detecting device and this source.
A kind of method is provided, has been used for gathering one or more groups imaging data.The method comprises the behavior of a plurality of X-ray sources position of triggering the angled source be disposed in the detecting device gap.When being triggered, each X-ray source position emission X-ray.Producing corresponding signal with each of X-ray source position corresponding corresponding detector array place of triggering.Each corresponding signal is corresponding to the X-ray that incides described detector array and list.Corresponding claim also is provided, has related to appreciable machine readable medium, this medium comprises the code that can carry out to carry out these actions.
Description of drawings
When representing the detailed description below reading of identical parts with reference to same Reference numeral in institute's drawings attached, these and other features of the present invention, aspect and advantage will become more obvious, wherein:
Fig. 1 is the schematic diagram of exemplary according to an embodiment of the invention static CT system;
Fig. 2 is the schematic diagram of exemplary source-detector arrangement of using together of the system with this type that is shown in Fig. 1;
Fig. 3 is the schematic diagram for the exemplary transmitting site of the distributed source of Fig. 2;
Fig. 4 is the schematic diagram of another exemplary source-detector arrangement of using together of the system with Fig. 1;
Fig. 4 A is the stereographic map of exemplary source-detector arrangement of Fig. 4;
Fig. 5 A describes the source track of non-angled source-detector arrangement or the curve synoptic diagram of object space;
Fig. 5 B describes the source track of angled source-detector arrangement of Fig. 4 or the curve synoptic diagram of object space;
Fig. 6 is the schematic diagram of another exemplary source-detector arrangement of using together of the system with Fig. 1;
Fig. 7 is the schematic diagram of one exemplary source again used together of the system with Fig. 1-detector arrangement;
Fig. 8 is the schematic diagram of one exemplary source again used together of the system with Fig. 1-detector arrangement;
Fig. 9 is the schematic diagram of another exemplary source-detector arrangement of using together of the system with Fig. 1;
Figure 10 describes to be used for reproducing the process flow diagram of the example logic step of data for projection according to an embodiment of the invention; And
Figure 11 describes to be used for reproducing the process flow diagram of the example logic step of data for projection according to an embodiment of the invention.
Embodiment
Referring now to Fig. 1, the CT system is always by Reference numeral 10 diagrams and expression.CT system 10 comprises scanner 12, and it forms cylindrical stand and comprises one or more static X-radiation profile sources 14 and one or more static digital detector array 16, and is as described in more detail below.Scanner 12 is configured to receive supporting member 18, and this supporting member 18 passes imaging space and is placed with the object that will be scanned on it.Supporting member 18 can be moved and pass the hole in scanner 12 in order to an object or a plurality of object are properly positioned in the imaging space that scans in imaging sequence (imaging sequence) process.In one embodiment, described supporting member 18 is travelling belts, and this travelling belt is configured to make the object of experience imaging continuous or approximately continuous by scanner 12.In other embodiments, supporting member 18 is platform or supporting mass, they be configured to with object or moving patients in scanner 12.
Described system also comprises radiation source controller 24, supporting mass controller 26 and data acquisition circuit 28, wherein some or all can working under the guidance of system controller 30.Radiation source controller 24 is regulated the timing of the detector-segments emission X-ray on around distribution X-ray source 14 towards opposite side from X-ray source position 34.In exemplary static CT uses, radiation source controller 24 can trigger one or more addressable electronic transmitters with the specific time interval, and this addressable electronic transmitter provides the X-ray of launching from the source position 34 of distribution X-ray source 14 so that the multiple collection of the X-ray intensity data of transmission.In certain embodiments, for example, radiation source controller 24 in order addressable ground triggering X-ray source position 34 in case around scanner 12 adjacent the or non-conterminous X-transmitted intensity that obtains transmission.Many this measurement data are collected with the imaging order, and the detector acquisition circuitry 28 that is couple to detecting element as described below receives signal and processes these signals from described detecting element and is used for storing and/or image reproducing.In other structures, these signals can be processed in real-time that the imaging object in the imaging space of scanner 12 is reproduced.Then supporting mass controller 26 is used for supporting member 18 and object are suitably located with imaging in the plane of divergent-ray or solid space.Supporting member 18 can be in the imaging sequence process or between move, this depends on the imaging protocol of employing.
The general operation of adjusting radiation source controller 24, supporting mass controller 26 and detector acquisition circuitry 28 of system controller 30.Therefore system controller 30 can make radiation source controller 24 trigger to launch x-ray radiation, and coordinates these emissions in the imaging sequence process that is limited by system controller 30.System controller 30 also can coordinate the motion of adjusting supporting member 18 with these emissions in case measure interested different objects or volume transmission the X-ray intensity data or in order to realize the imaging of different mode, axial or helicon mode for example.System controller 30 also receives storage, processing and/or the transmission of the data for projection that is collected by the data of detector acquisition circuitry 28 collections and coordination.Although be represented as parts of system controller 30 in Fig. 1, but in reality was implemented, radiation source controller 24, supporting mass controller 26 and detector acquisition circuitry 28 can be arranged in identical physical arrangement or can not be arranged in identical physical arrangement.
Will be appreciated that, these controllers, and different circuit really described here can be implemented as hardware circuit, firmware and/or software.The specific protocol that for example is used for imaging sequence generally will be limited by the code of being carried out by system controller 30.And initial treatment, adjusting (conditioning), filtering and other operations of carrying out on the X-ray intensity data of the transmission that is gathered by scanner 12 can be carried out in one or more parts that Fig. 1 describes.For example, as described below, be arranged on detecting element 36 in many rows multiple row of detector array 16 can produce the charge depletion in the expression photodiodes simulating signal so that these simulating signals generally corresponding to the X-ray energy that incides during the sample time of regulation on corresponding detecting element 36.In one embodiment, the electronic equipments that are scanned in instrument 12 of these simulating signals are converted into digital signal and are collected by detecting device Acquisition Circuit 28.Section processes can occur at the moment, and these signals finally are sent to system controller 30, is used for further filtering and the processing at this embodiment.
Imaging system 10 can comprise software, hardware and/or the firmware of processing and reproducing for image, and they generally are described to image processing circuit 40.Image processing circuit 40 can be configured to communicate by letter with system controller 30 or can be set to the part of system controller 30.In addition, image processing circuit 40 can be configured to be connected PACS with communication system with the Local or Remote system that is connected or workstation 42 or the picture archiving that connects) 44 communications or be implemented as this locality of connection or the part of long distance system or workstation 42 or be implemented as the picture archiving of connection and the part of communication system (PACS) 44, wherein said PACS is configured to cross and/or not processed data for projection with stores processor.Will recognize that as those technician in this area, this image processing circuit 40 can be by the CT data for projection of various mathematical operations, algorithm and technical finesse collection.For example, traditional filtered back projection (back-projection) technology can be used to process and reproduce the data that gathered by imaging system 10.The technology that also can adopt other technologies and be combined with filtered back projection.
In one embodiment, imaging system 10 also comprises image displaying circuit 48, and it can make the view data of described processing show with electronics or printing form respectively, for example on display 50 or printer 52.Those skilled in the art will recognize that this, and this image displaying circuit 48 can be implemented as software, hardware and/or firmware and can be set to the part of the part of system controller 30, operator interface or the part of the workstation of connection.
The scanner 12 of static CT system 10 preferably includes one or more distribution X-ray sources 14 and one or more digital detector 16, is used for received radiation and processes respective signal, to produce data for projection.Fig. 2 illustrates the exemplary scanner 12 of a part, and this scanner 12 defines the imaging space with Z axis, and along Z axis, the one or more objects that are imaged pass or enter into imaging space.As shown in Figure 2, in exemplary enforcement, distribution X-ray source 14 can comprise one group of addressable X-ray source position 34, and this X-ray source position 34 is coupled to radiation source controller 24 shown in Figure 1, and is triggered by source controller 24 in 12 operating periods of scanner.In one embodiment, addressable X-ray source position 34 of distributed source 14 is to use the electron beam emitter of the electron beam that emission accelerated by head for target to be implemented.This target at electron beam hits time emission x-ray radiation 60 thereon, is for example tungsten rod or tungsten element.X-ray source can be operated with the form of reflection or transmission.Under reflective-mode, the X-ray means the sidepiece that mainly is created in the described target identical with described electron impact.Under transmission mode, the X-ray means the opposite side portion that is created in the described target of electron beam shock.Described X-beam can be collimated before entering into imaging space so that they when crossing described imaging space X-ray 60 be formed the taper of hope, as be described fan-shaped, or other shapes.
Although more than described a possible embodiment of the distribution X-ray source 14 with a plurality of addressable X-ray sources position 34, it may be also other embodiment.For example, in one embodiment, imagined a kind of cold-cathode emitters, this cold-cathode emitters will be housed in vacuum casting.It is interior and spaced apart with described transmitter that then distributed stationary anode is disposed in described shell.Other materials, structure and principle of operation can be used to distributed source 14 certainly.For example, an emitter can be configured to electron beam to be sent to a plurality of positions on described target in order to produce a plurality of x-ray radiation bundles.This emitter can be one of many available electron emitting devices, for example, and thermionic emitter, cold-cathode emitters, the transmitter based on carbon, optical transmitting set, ferroelectric transmitter, laser diode, monomer semiconductor etc.
As said, this static CT technology is based on uses a plurality of distributions and addressable electron emission source to be used for producing addressable, distribution X-ray source position 34 in a large number along one or more radiation sources 14.And, each distributed source of radiation 14 can be designed to crew-served single single vacuum cover or a plurality of vacuum (-tight) housing and be associated.Independent X-ray source position 34 can be independently and respectively addressing so that can be in real time in by the imaging sequence process of described imaging protocol definition from each X-ray source position 34 described radiation of triggering of some points.In other structures, X-ray source position 34 is addressable in a logical groups, and for example paired or triplets X-ray source position 34 can be triggered together.When needed, not only an X-ray source position 34 can be triggered in real time at any time simultaneously, perhaps X-ray source position 34 can be triggered to simulate around the rotation of described imaging space with particular order, and perhaps the order with any hope is triggered around described imaging space or plane.
Turn back to Fig. 2, addressable X-ray source position 34 is around the circumferential registration of described imaging space, when being triggered, X-ray 60 passed on the corresponding part 62 that described imaging space is transmitted into detector array 16.In detector array 16, the X-ray incides part detecting element 36 on it and produces the signal that can be read by the detector acquisition circuitry 28 of Fig. 1.In one embodiment, detecting element 36 comprises device, photodiode and the relevant thin film transistor (TFT) of flicker type.The x-ray radiation 60 that clashes into detecting element 36 is converted into the lower photon of energy by scintillator, the described photodiode of these photon strikes.Therefore depleted at the electric charge that described photodiodes keeps.Transistor can be controlled to recharge and therefore measure the electric charge that exhausts to photodiode.By sequentially measuring the charge depletion in each photodiode, wherein each is corresponding to detecting element 36 or pixel in each collection data that gather, data are collected, and these data are to pass the coding of energy of the transmitted radiation of object at each pixel location place.The data of this collection can be processed so that described simulating signal is converted into digital value, and be converted into the line integral of expression linear attenuation coefficient, and after might be filtered, be sent to the image processing circuit 40 of imaging system 10 as above.Although described detector array 16 according to the energy integral device based on scintillator, other detector types for example detecting device of gas ionization, Direct Transform, photon counting or resolution energy are same being fit to.
As shown in Figure 2, gap 66 is arranged between the distributed source 14 and detector array 16 of interface.Especially, in order to allow suitably to launch the X-ray from the X-ray position 34 of distributed source 14, detecting element 36 does not have adjacent source 14, produces gap 66 in detector array 16 around distributed source 14.This gap 66 can owing to not having detecting element 36 therefore to cause collecting incomplete data for projection on mathematics, therefore can cause the image of image artifacts or generation other quality lower than the picture quality of wishing in gap 66.
In one embodiment, the independent trigger sequence of the X-ray source position 34 of distributed source 14 is modified to increase the mathematics completeness of data for projection of the object of the imaging space that uses supporting member 18 to pass scanner 12.Especially, in one embodiment, the X-ray source position 34 of distributed source 14 is that the pattern with non-order is triggered separately, is triggered after namely the position of contiguous X-ray source can be in not triggering described triggering principal direction the first X-ray source position.In one embodiment, triggering type can be selected to or be configured to so that can not incided on detector array 16 by before or on the part detector array 16 that also incides of the X-ray of X-ray source position 34 emissions that trigger subsequently by the X-ray of X-ray source position 34 emissions that trigger.
In another embodiment, the first X-ray source position can be triggered, thereupon with the second X-ray source location triggered, wherein said the second X-ray source position around scanner 12 with counterclockwise from the first X-ray source position skew fixed angle, for example 90 °.Then, the X-ray source position of contiguous in the counterclockwise direction the first X-ray source position is triggered, and the X-ray source position with contiguous in the counterclockwise direction the second X-ray source position is triggered thereupon, etc.By this way, use the positional representation X-ray source position, angle around the circular scan instrument, possible X-ray source position starting or activation patterns can be around 0 °, 90 °, 1 °, 91 °, 2 °, 92 ° of scanner 12 etc.Although integer angular be described in this be provided by example and be in order to simplify explanation, but a technician in this area will appreciate that not only an X-ray source position 34 can the interval between the integer angular position on scanner 12, namely can be arranged on distributed source 14 more than 360 X-ray source positions 34.And angular variation is not 90 °, such as 45 °, 120 °, 60 ° etc., can be used yet.And, can expect triggering clockwise or counterclockwise X-ray source position 34.
Get back to now Fig. 3, another embodiment of this technology is that the mode of the example simplified is described, and wherein only has eight X-ray source positions 72,74,76,78,80,82,84,86 to be described.In this example, described X-ray source position is triggered respectively according to following order.
| 1 | X-ray source position 72 |
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| 14 | X-ray source position 72 |
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[0046]Those skilled in the art will recognize, hundreds of X-ray source positions 34 can actually appear on distributed source 14; This example is simplified and is provided and only is used for the diagram purpose.It is the scanner 12 that proportionally to draw and can be applied to having any amount of X-ray source position 34 by the type of the illustrated activation patterns of described example.
The type of activation patterns described above is corresponding to two spiral scans that gather substantially simultaneously; Other suitable non-orders (or even for arbitrarily) activation patterns allows in any way recording projection data and/or allows described data for projection along limiting the surperficial sampled of described imaging space, rather than only along one or more helical trajectories.In the present example, yet, spatially intersect and to using supporting member 18 to pass the mathematics completeness of data for projection of collection of imaging object of the image space of scanner 12 corresponding to the data for projection of two spiral scans.Especially, in these embodiments, X-ray source position 34 in the X-Y plane identical with other X-ray sources position 34, but owing to using supporting member 8 mobile objects, in fact have different positions with respect to other X-ray sources position 34 in the Z direction.Due to the skew in described X-Y plane and due to the displacement along Z axis, the data for projection of loss can be compensated by using the data for projection corresponding with described the second helical projection data set.Usually, described compensation ray is from the source position 34 of in identical with unmeasured ray as above X-Y position or conjugation X-Y position, and those skilled in the art will recognize this.
For example, for the data for projection that uses above-mentioned technology to gather, because the data for projection in a helical projection data set that exists gap 66 to lack can be compensated by using the data for projection from the second helical projection data set.Especially, in one embodiment, for corresponding with the data for projection of disappearance each X-ray source position 34, the X-ray source position will be projected to the π joint part of described first spiral in gap 66 and be determined.Yet, be not the interpolated value of these X-ray sources of back projection position, but for this position, from the data for projection of other the spirochetal X-ray sources positions back projection disappearance of corresponding but skew.
By this way, two, three, or generally speaking, n the projection that X-ray source position 34 provides on detector array 16 compared with the first X-ray source position, at this detector array 16 places, gap 66 is offset along Z axis, and allows to utilize the data for projection of other disappearances.In one embodiment, reproduction can be performed as independent reproduction, and wherein " appointment " of two spirals (that is, skew or initial) is exchanged.Described two reproductions can be average, this equates and apply the weight that have the pass with three dimensional image in back projection's process.Those skilled in the art will recognize this, and the skew between two spirals should be selected to so that the projection gap area of each spiral does not overlap each other or overlapping minimum.
In addition, get back to now Fig. 4 and Fig. 4 A, in another embodiment, distributed source 14 and possible detector array 16 are with respect to the main cylinder axis inclination inclination angle [theta] of described scanner, with respect to the Z axis of scanner.Those skilled in the art will recognize this, and in this embodiment, distributed source 14 can be the oval-shaped or tilted circle that radius is enough to gather needed data for projection.In this structure, the ray of emission can pass through described imaging region twice.By changing the point-to-point speed of inclination angle [theta] and supporting member 18, this redundancy can be optimized or increase.Like this, otherwise can be compensated or recover due to the data for projection that gap 66 lacks.Vertical and the horizontal boundary of single detecting element 36 can be oriented as shown in Fig. 4 A, perhaps they can be respectively with limited by described scanner geometric shape axial with aim at across axial direction.
For example, referring now to Fig. 5 A, the graph of relation of Z value and rotation angle α is used to describe the traditional structure of scanner 12, and wherein distributed source 14 is θ=0 without the pitch angle.Line 94 represents given Z position.By supporting member 18 during across scanner 12, this only gathers a secondary data for each part of object along helical source trajectory by 96 expressions of source trajectory when object, causes in detector array 16 missing data corresponding to gap 66.The cross means of source trajectory 96 and the Z position line 94 is when the position, angle in its described source during by given Z position.Only there is such point of crossing.
Get back to now Fig. 5 B, the similarity relation curve map of Z value and rotation angle α is used to describe the structure of scanner 12, tilts with respect to Z axis at this distributed source 14, i.e. θ ≠ 0.In this embodiment, for some Z values, a plurality of Sloped rotatings angle α is arranged, as shown in the point of crossing of line 94 and line 96.When object passed through supporting member 18 across scanner 12, this was by 96 expressions of source trajectory, and the data of described final acquisition have some redundancies, and it can be used to compensate the mathematical incompleteness of described data in the reproduction process.In fact, some zone of reproducing part can be increased other data for projection so that improve mathematical completeness.
With reference now to Fig. 6 and 7,, in another embodiment of present technique, distributed source 14 is set to U-shaped or is roughly semicircular source 100, and it has approximate 180 ° or larger angular spread.For example, in one embodiment, the angular spread that is roughly semicircle source 100 is 180 ° of segment angles that add emission X-ray.In the embodiment of this embodiment, be described in Fig. 6, columniform detector array 102 is configured to be approximately around scanner 12 span of 360 °.Gap 66 is arranged in detector array 102 and is roughly semicircular distributed source 100 to hold, but the place in semicircular source 100 does not appear on detector array 102 not needing to hold roughly.In another embodiment of this embodiment, be shown in Fig. 7, part detector array 104 is around enough span settings of scanner 12, with recording projection data when the end points X-ray source position 34 in semicircular source 100 roughly is movable, namely the angular range that strides across of the detector array 104 of part is equal at least the angle that is roughly semicircular source 100 and adds that other scope is to comprise the segment angle of emission X-ray.Gap 66 is arranged in detector array 104 partly and adapts in those parts that are roughly semicircular source 100 to adapt to the described not needs that are roughly semicircular distributed source 100 but do not appear in detector array 104 partly.By this way, for two embodiment of the description of Fig. 6 and 7, detector gap 66 scanner 12 than polarizers of big angle scope in be removed, this has improved the mathematical completeness of the data for projection that gathers.
About Fig. 6 and 7 embodiment that describe, the data for projection of perfect set can be obtained in some cases.For example, if for each point in the visual field, the cluster sampling of subgroup X-ray source position 34 pathways, when each in these corresponding X-ray sources position 34 is triggered, corresponding point is projected on detecting device 102,104, the line segment that connects the end points in this path comprises each point, can obtain the data for projection of perfect set.
And, use described semicircle source 100 structures that are roughly, as for the degree of obtainable redundant data, described redundant data can be used to reduce the noise in reproduced image.For example, noise reduces and can be achieved by the data combination reproduction that obtains from hyperchannel (may be overlapping).Those skilled in the art will recognize, the existence of these passages is depended at the trigger sequence that is roughly the X-ray source position 34 on semicircular distributed source 100.For example, specifically with reference to figure 6 and 7, multiple similar spiral data acquisition is to obtain by sequentially trigger X-ray source position 34 from the end to end that is roughly semicircular source 100.And, by determine whether to skip one or more X-ray sources position 34 in trigger sequence, for example by triggering X-ray source position 34 and can select or revise pitch every one or every three successively along being roughly semicircular source 100.Especially, by skip X-ray source position 34 in this trigger sequence, can reduce spirochetal effective pitch.Therefore because described pitch has been reduced, be placed with the density that has increased the relative position of recording projection data on the Z direction of partial circle cylindricality of all source positions thereon.Simultaneously, be that the density of the relative X-ray source position on X-Y plane reduces on across axial direction.
Remember aforementioned content, conveyor screw and pitch can be configured to so that for each plane by reproduction point, and X-ray source position 34 in its vicinity.For example, wish in the arch section sampling near the non-circular reproduction visual field more intensive.This is to be achieved by the quantity that changes the X-ray source position 34 skip in corresponding trigger sequence.After this manner, similar spiral scanning can given variable pitch, this variable pitch in the whole visual field or the part interested in the visual field complete data for projection is provided.Similarly, by between a plurality of X-ray source location activation sequences alternately, can produce the similar spiral section, these similar spiral sections are overlapping in the scope of Z axis at them.
The advantage of Fig. 6 and 7 described embodiment is, more rare and at the axial direction comparatively dense across axial direction, therefore the X-ray position can be counted as the two dimension sampling on surface rather than be counted as one group of one dimension sampling of independent spiral section relatively due to described sampling.In addition, trigger sequence can be designed to and/or be configured to redirect between helical acquisition so that gather the data for projection of perfect set.
In another embodiment, the mathematical completeness of data for projection is that section a plurality of by distributed source 14 is separated into, that might be offset is able to improved.For example, referring now to Fig. 8, an embodiment has been described, wherein said distributed source is set to three distributed arc source 110 in the skew of the Z of scanner 12 direction, each strides across the different angular range of scanner 12, for example 120 °, but usually, distributed arc source 110 meeting spans are less than 180 °.In the example of describing, each distributed arc source 110 strides across the 120 ° of different scopes of total 360 ° that limited by scanner 12, but those skilled in the art will recognize, if desired, total distributed arc source 110 in fact span is less than or greater than 360 °.For example, in one embodiment, total distributed arc source 110 in fact can 180 ° of segment angles that add emitted radiation 60 of span.For this structure, can use two or more arcuate source 110 to gather necessary data for projection.
In described embodiment, detector array 16 is also segmentation, so that for each distributed arc source 110, provides corresponding detector-segments 112 on the opposite side of each distributed arc source 110 of scanner.In described embodiment, detector-segments 112 strides across larger than the angular range of the distributed arc source 110 of they correspondences.Especially, no matter being described to comprise the angular range of corresponding distributed arc source 110, detector-segments 112 adds how other angular range needs to consider the segment angle of the X-ray of emission.In other words, in this embodiment, the angular region that the angular region of detector-segments 112 equals distributed arc source 110 adds the scope of holding by the segment angle of the X-ray of arcuate source 110 emissions.Be the collecting of integration of the X-ray channel of the linear attenuation coefficient in the object that is imaged for information about due to what measure, so detector portion can be substituted by the source part, vice versa.Those skilled in the art will recognize, these substitute can depend on various system constraints, the relative cost of for example distribute X-ray source and detector portion.Distributed arc source 110 spans less than 180 ° and corresponding detector-segments 112 not can with the overlapping embodiment of distributed arc source 110 in, as shown in Figure 8, because distributed arc source 110 does not need to be accommodated in the scope of corresponding detector-segments 112, therefore can have no to consist of with gap detector-segments 112.Because very close to each other in detector-segments 112, so on mathematics, complete data for projection is gathered by detector-segments 112.In other embodiment, detector-segments 112 can simply be set to detection ring, and it is still very close to each other relative with each arcuate source separately that the gap that provides for distributed arc source 110 is provided this detection ring, therefore can improve the completeness of data.
With shown in Figure 8, distributed arc source 110 and detector-segments 112 are that object is along with they are imaged as being offset by the direction of translation by supporting member 18 in the Z direction as mentioned above.In described embodiment, distributed arc source 110 and detector-segments 112 are offset so that they can not be interfered each other, and namely the X-ray by distributed arc source 110 emissions only is incident upon on corresponding detector-segments 112, and is not incident on other detector-segments.In another embodiment, with reference now to Fig. 9, distributed arc source 110 and detector-segments 112 can be offset less scope so that detector-segments 112 has overlapping or adjacent zone in the Z direction.In this embodiment, some or all of X-ray sources position 34 for each distributed arc source 110, can be from not only detector-segments 112 recording projection datas, yet, distributed arc source 110 still not and detector-segments 112 interference, namely in detector-segments 112 without the need for the gap that holds distributed arc source 110.
In one embodiment, X-ray source position 34 on each distributed arc source 110 of Fig. 8 and Fig. 9 can be triggered separately or in order to provide or to trigger separately near the structure of one or more skew spiral scans, namely for the object by described imaging space, gather helical projection data by scanner 12.For example, in order to simplify, the X-ray source position 34 of scanner 12 is described again based on angle, at first the X-ray source position of 0 ° of position on scanner 12 can be triggered, and is X-ray source position 34 of the X-ray source position 34 of 34,1 ° of X-ray source position of 34,270 ° of X-ray source positions of 34,180 ° of X-ray source positions of 90 ° and 91 ° etc. subsequently.Also can adopt the angular deflection outside 90 °, for example 45 °, 120 °, 60 °.Those skilled in the art will recognize, this trigger sequence will obtain the data for projection corresponding to a plurality of helical trajectories, and wherein said helical trajectory is spatially cross one another, and is namely spatially interlaced, perhaps spatially skew each other.Will recognize further this, be correlated with along pitch and the interval of the arcuate source 110 of Z direction.If arcuate source 110 is not separated and the equidistant distance that strides across during the spiral integer number of turns, (that is, 0 °, 90 °, 180 °, 270 °, 1 °, 91 ° of given trigger sequences ...) will produce spiral section rather than one group of continuous helical of separating.Therefore, in certain embodiments, described arcuate source interval is fixed to so that the use optimization of detecting device (or factor of any other hope).In these embodiments, after definite described arcuate source interval, can determine the quantity of pitch and spiral, and the trigger sequence of determining described correspondence.
And, the quantity of the distributed arc source 110 that provides and the angular region of each arcuate source are provided, continuous X-ray source location triggered can occur in occasionally on identical distributed arc source 110 or never occur on identical distributed arc source 110.As mentioned above, because very close to each other in each detector-segments 112, the data for projection that therefore gathers is complete on mathematics.In addition, since distributed arc source 110 and detector-segments 112 can be staggered along the Z axis of described imaging system, therefore can trigger simultaneously the one or more X-ray sources position 34 on each distributed arc source 110, namely can be triggered simultaneously in the position of 1 °, 91 °, 181 ° and 271 °, because they are not transmitted in the X-ray that overlaps each other on separately detector-range.Above-mentioned scanning process makes along with object strides across imaging space, obtains the data for projection of a plurality of cross-helicities.
Also can adopt other trigger sequences for the embodiment that describes in Fig. 8 and 9.For example, can realize simulating the trigger sequence that traditional third generation rotates the CT system.In this embodiment, at first the X-ray source position 34 of 0 ° of position on scanner 12 can be triggered, and is X-ray source position 34 of locating, 34,4 ° of the X-ray source positions located, 34,3 ° of the X-ray source positions located, 34,2 ° of 1 ° of X-ray source positions of locating etc. subsequently.In this embodiment, except when be transitioned into when reaching the angular region of distributed arc source 110 next distributed arc source 110 constantly outside, continuous X-ray source location triggered generally will occur on identical distributed arc source 110.As previously mentioned, because very close to each other in each detector-segments 112, the data for projection that therefore gathers is complete on mathematics.The scanning process of this order allows to gather single helical projection data set.And because the X-ray source position 34 on each distributed arc source 110 is distributed, so they can be triggered to realize specific imaging purpose with order or even the random sequence of any hope.This random or any trigger sequence can allow described data for projection sampled along the cylindrical surface that forms described imaging space, rather than only along one or more helical trajectories.
Those skilled in the art will recognize this, and said structure is for axial, spiral or other suitable scan pattern conceptions.Yet, depending on concrete application, some structure can be more suitable in these one or more patterns, and for example described axial mode is used for medical applications, and helicon mode is used for for example purposes of luggage scanning.And these sources and the detecting device described in above structure can have different diameters, size, scope etc.And these sources and detecting device can be made of the part of linear segment, planar section or other space distributions, and it is near said structure.And, using above-mentioned trigger method, other or correlated source and/or detector arrangement can by being used, perhaps allow view data such as above-mentioned the collection.The name that the example of these other sources and/or detector arrangement was published on May 26th, 2005 is called in the U.S. Patent application 2005/0111610A1 of " system and method for stationary ct " and finds, and its integral body is incorporated in this with way of reference.
Those skilled in the art will appreciate that, structure described here overcome or for example compensated in addition in the spiral scan structure of static CT system, restriction that on mathematics, incomplete data for projection is measured.Exactly, under helical scan mode, for effective source rotation of certain angular region, on mathematics, the restriction of incomplete data for projection is reduced or eliminates.It is more complete on mathematics that this effect causes data for projection to be measured, the picture quality of the cone-beam reconstructions of using for improvement of static CT.
Those skilled in the art will appreciate that, in certain embodiments, organize interlaced helical projection data the scanner structure of front and X-ray source trigger method allow more and are gathered.This interlaced helical projection data can provide various reproduction chances.For example, two reproduction strategies are summarized in Figure 10 and 11 described example logic.These tactful various aspects can be implemented as one sees fit by the image processing circuit 40 of Fig. 1.The exemplary strategy that reproduces of Figure 10 is to use collimated beam to be similar to and use two-dimensional reconstruction algorithm separately, and the accurate cone-beam reconstructions algorithm of three-dimensional that the exemplary reproduction strategy of Figure 11 utilizes modification.Those skilled in the art will appreciate that, can use other or dependent reproduction technology together with data that the scanner structure of utilizing the front and X-ray source trigger method obtain.The example of these other reproducing technologies can be authorized on August 30th, 2005, name is called in the United States Patent (USP) 6,937,689 of " be used for distribution X-ray source CT system method and apparatus ", and this patent integral body by reference is incorporated into this.
Get back to now Figure 10, at first data for projection 120 is gathered (piece 122).Data for projection 120 can be by one or more above-mentioned technology or by the other technologies of the data for projection that is suitable for gathering many interlaced helical and the intensive data for projection set of information of the data for projection of the many interlaced helical that collect.This data for projection 120 is spiral interpolation, even be similar to (piece 124) to produce one group of interpolated projections 126.Those skilled in the art will appreciate that, interpolation procedure 124 is a kind of method of approximation, when the cone angle of system architecture not too the time this method of approximation more suitable.Usually, this method of approximation is less than or equal to 2 ° for cone angle and will accepts.Projection 126 after interpolation then reproduced (piece 128) to produce reproduced image 130.Reproduce step 128 and can carry out a kind of suitable two-dimensional reconstruction algorithm, for example two-dimensional axial reconstruction algorithm.Therefore these two-dimensional reconstruction algorithm calculating strength can provide very high recall factor lower than their three-dimensional equivalents.If the cone angle of described imaging system is still excessive, can uses approximate or accurate cone-beam reconstructions principle and reproduce described space.
The representation approach of summarizing in Figure 10 in addition, allows to improve the reliability of CT imaging system 10.Especially, if the distributed source 14 of a part or detector array 16 (arcuate source 110 or the detector-segments 112 for example described in Fig. 8 and 9) are malfunctioning, can use for example part reproducing technology operation scanner 12 of short scanning technique, wherein said reproducing technology need to be less than the data for projection of 360 ° for suitable picture quality.Therefore system 10 can keep operation until distributed source 14 or detector array 16 can be repaired or be replaced.
Turn to now Figure 11, described the reproducing technology that substitutes.In this exemplary embodiment, along distributed source 14 (for example arcuate source 110 of Fig. 8 and 9 scanner embodiment), use X-ray source position 34 recording projection datas 132 (piece 134) of unordered trigger sequence, wherein said distributed source 14 causes forming projected dataset 132, and this projected dataset 132 is by in the surperficial sampled of image volume rather than along a paths.The unordered trigger sequence that be used for to gather in step 134 is to be achieved by being converted into binary, as to put upside down binary digit order and triggering X-ray source position 34 according to the order of the numbering of these modifications with X-ray source position 34 numberings, with these numberings.This triggering method is called as bit reversal and triggers (BRF).In addition, the X-ray source position 34 of fixing (generally less, namely less than 10) quantity can be skipped between each triggers.This triggering method is called as ultralow pitch spiral (SLPH) technology.In another system of selection, the position, angle of each source position 34 (after first) is by approximate, D (sqrt (5)+1)/2 degree to be increased to (wherein D is total angular region of single arcuate source, and angle is unit) determined on the position, angle of the source position 34 of triggering in the past.In the situation that final angle is greater than D, D can be deducted from this angle so that described result 0 to D.This triggering method is called as golden ratio and triggers (GRF) technology.If source position 34 on angle be uniformly-spaced open and each arcuate source 110 or other distributed sources 14 structures in the quantity of source position 34 be selected from striking Poona odd sequence (namely 1,1,2,3,5,8,13,21,34,55 etc.), this technology is easily implemented.The quantity of (to advance) source position that advance in the case, always equals the numeral of the front in striking Poona odd sequence.In other words, if we define F
nBe n striking Poona odd number word, have 377 (that is, F in each arcuate source 110
14) source position 34, in each step, the index of source position 233 (that is, the F that can be advanced
13).Because each striking Poona odd number word is with the first two sum, when there being F
nDuring individual total source position, F in one direction advances
n-1Equal to advance in the opposite direction F
n-2
Those skilled in the art will appreciate that, because the emission focus, sampled rather than path, surface is moved in the X-ray source position 34 of namely triggering around the surface that limits described imaging space.Therefore, data for projection 132 can reproduced (piece 136) use the reproduced image 138 of three-dimensional cone beam representation approach with generation, and wherein said algorithm has been modified to and has comprised sampling method.For example, the representation approach that adopts at piece 136 can be designed to or be configured to adapt to X-ray source position 34 along the sampling of a part of periphery rather than take a sample along spiral path.
Be in some scanner embodiment (for example described in Fig. 8 and 9) about one of advantage of the above-mentioned scanning technique of Figure 10 and 11, it is so much that the longitudinal extent of each detector array 16 in scanner 12 roughly reduces the quantity of arcuate source 110, and this is because arcuate source 110 can operate simultaneously.For example, be that the third generation structure of helical acquisition agreement is required if longitudinal length is the detecting device of 60 centimetres, 4 arcuate source 110 are included in suitable static structures, and the longitudinal length of detector-segments 112 can be reduced to 15 centimetres, namely has been reduced 4 times.Those skilled in the art will appreciate that, the geometric condition of other scanners, throughput parameter and scanner and imaging protocol factor also affect the degree that detector-range can reduce.In the embodiment that detector-range is reduced, dispersion also is used in reducing of detector-range and reduces.
Those skilled in the art will appreciate that, scanner geometries described here and reproducing technology have overcome or for example compensated in addition the restriction that incomplete data for projection is measured on the mathematics of the spiral scan structure of static CT system.Exactly, under helical scan mode, for effective source rotation of certain angular region, on mathematics, the restriction of incomplete data for projection is reduced or eliminates.It is more complete on mathematics that this effect causes data for projection to be measured, and it can be reproduced by technology described here, comes for improvement of picture quality.
Although can carry out various modifications and adopt other forms the present invention, illustrate and describe in detail specific embodiment by the example in accompanying drawing.Yet, will be appreciated that the present invention is not intended to be confined to disclosed concrete form, and the present invention to comprise all modifications, the equivalent that falls in the spirit and scope of the present invention that limited by following appended claims and substitute.
Claims (24)
1. method that be used for to gather the data for projection of two or more groups comprises:
Trigger a plurality of addressable X-ray sources position of annular source, make when being triggered each X-ray source position emission X-ray, a plurality of addressable X-ray sources position of wherein said triggering annular source comprises around the circumference of described annular source triggers the X-ray source position disorderly; And
The place produces corresponding signal in corresponding with each corresponding triggering of X-ray source position detector array, wherein each corresponding signal is corresponding to the X-ray that incides described detector array and list, and wherein total corresponding signal corresponding to the scan-data of the spatially interlaced helical of two or more groups.
2. the method for claim 1, wherein, described a plurality of addressable X-ray sources position is triggered with following pattern, namely by the X-ray of the X-ray source position emission that triggers can not incide detector array list by before or the part detector array that also incides of the X-ray of the X-ray source position emission that triggers subsequently list.
3. method as claimed in claim 1, wherein said a plurality of addressable X-ray sources position is triggered with paired order, so that the triggering of every pair of X-ray source position is offset fixed angle, and each follow-up to along described annular source with respect to front to and advance.
4. an imaging system, comprise
Radiation source controller (24), it is connected to distribution X-ray source (14), described radiation source controller (24) is configured to trigger a plurality of addressable X-ray sources position of described distribution X-ray source (14), make when being triggered each X-ray source position emission X-ray, wherein said radiation source controller (24) is further configured with the circumference around described distribution X-ray source (14) and triggers disorderly the X-ray source position; And
Detector acquisition circuitry (28), be connected to x-ray detector array (16) to be received in the corresponding signal at corresponding with each corresponding triggering of X-ray source position detector array place, wherein each corresponding signal is corresponding to the X-ray that incides described detector array and list, and wherein total corresponding signal corresponding to the scan-data of two or more sets spatially interlaced helical.
5. system as claimed in claim 4, wherein, described radiation source controller (24) is further configured to trigger the X-ray source position, make X-ray by the X-ray source position emission that triggers can not incide detector array list by before or the part detector array that also incides of the X-ray of the X-ray source position emission that triggers subsequently list.
6. system as claimed in claim 4, wherein, described radiation source controller (24) is further configured with paired order triggering X-ray source position, so that the triggering of every pair of X-ray source position is offset fixed angle, and each follow-up to along described distribution X-ray source (14) with respect to front to and advance.
7. method that be used for to gather the imaging data of two or more groups comprises:
Trigger a plurality of addressable X-ray sources position of annular source, make when be triggered each X-ray source position launch X-ray, wherein said a plurality of addressable X-ray sources positions is triggered disorderly; And
The place produces corresponding signal in corresponding with each corresponding triggering of X-ray source position detector array, and wherein each corresponding signal is corresponding to the X-ray that incides described detector array and list.
8. method as claimed in claim 7, wherein said a plurality of addressable X-ray sources positions are triggered so that the triggering of each X-ray source position is offset predetermined angular separation from the triggering of X-ray source position the preceding along described annular source.
9. method as claimed in claim 7, wherein said a plurality of addressable X-ray sources position is triggered so that when advancing along assigned direction around described annular source, has staggered X-ray source position on the annular source between the X-ray source position of each triggering and the X-ray source position that was triggered in the past.
10. method as claimed in claim 7, wherein, described a plurality of addressable X-ray sources position is triggered with following pattern, namely by the X-ray of the X-ray source position emission that triggers can not incide detector array list by before or the part detector array that also incides of the X-ray of the X-ray source position emission that triggers subsequently list.
11. an imaging system comprises:
Radiation source controller (24), it is connected to distribution X-ray source (14), described radiation source controller (24) is configured to trigger a plurality of addressable X-ray sources position of described distribution X-ray source (14), make when being triggered each X-ray source position emission X-ray, wherein said a plurality of addressable X-ray sources positions is triggered disorderly; And
Detector acquisition circuitry (28), be connected to x-ray detector array (16) to produce corresponding signal at corresponding with each corresponding triggering of X-ray source position detector array place, wherein each corresponding signal is corresponding to the X-ray that incides described detector array and list.
12. system as claimed in claim 11, wherein, described radiation source controller (24) is further configured to trigger described X-ray source position so that when along assigned direction around described distribution X-ray source (14) when advancing, and the distribution X-ray source (14) between the X-ray source position of each triggering and the X-ray source position that was triggered in the past is upper exists staggered X-ray source position.
13. system as claimed in claim 11, wherein, described radiation source controller (24) is further configured to trigger the X-ray source position, make X-ray by the X-ray source position emission that triggers can not incide detector array list by before or the part detector array that also incides of the X-ray of the X-ray source position emission that triggers subsequently list.
14. an imaging system comprises:
The annular detector array, this detector array comprises a plurality of detecting elements, these detecting elements be configured to produce with incide described annular detector array on the corresponding signal of X-ray;
Gap in described annular detector array, described gap comprise the disappearance detecting element of the whole circumference that is coiled into the image space;
Annular source, this annular source are arranged in the described gap of described detector array, and described annular source comprises a plurality of X-ray sources position that is configured to unordered triggering.
15. imaging system as claimed in claim 14, wherein, described a plurality of X-ray sources position is configured to trigger in unordered mode, make X-ray by the X-ray source position emission that triggers can not incide detector array list by before or the part detector array that also incides of the X-ray of the X-ray source position emission that triggers subsequently list.
16. an imaging system comprises:
Be roughly semicircle or circle detection device array, this is roughly semicircle or circle detection device array comprises a plurality of detecting elements, described a plurality of detecting element is configured to produce the corresponding signal corresponding with inciding X-ray that described detector array lists, and comprising the gap, this gap does not have detecting element on the part of described detector array; And
Be roughly semicircular source, this is roughly semicircular source and is configured to from a plurality of addressable X-ray sources positions emission X-ray, wherein said a plurality of addressable X-ray sources position is configured to be triggered disorderly, wherein saidly is roughly semicircular source and completely or partially is arranged in described gap.
17. as the imaging system of claim 16, to make the one or more X-ray sources position passing the relevant range in the visual field and launch spatially more contiguous or than other X-ray sources positions being triggered more continually with respect to other X-ray source position that is triggered thereby wherein said a plurality of addressable X-ray sources positions is configured to be triggered.
18. as the imaging system of claim 16, wherein:
Be configured to be triggered so that skip between the X-ray source position of each triggering one or more X-ray sources positions with pattern alternately from described a plurality of addressable X-ray sources positions emission X-ray.
19. the imaging system as claim 18, wherein saidly be roughly semicircular source and be configured to described alternately pattern from described a plurality of addressable X-ray sources position emission X-ray, make the density of the relative X-ray position at recording projection data place increase and reduce across axial direction along described along the Z direction.
20. a method that is used for gathering one or more groups imaging data comprises:
Trigger disorderly a plurality of addressable X-ray source positions be roughly semicircular source so that when be triggered each X-ray source position launch X-ray, wherein saidly be roughly semicircular source and completely or partially be arranged in the gap that is roughly semicircular or circle detection device array; And
The place produces corresponding signal in corresponding with each corresponding triggering of X-ray source position detector array, wherein each separately signal corresponding to the X-ray that incides described detector array and list.
21. as the method for claim 20, wherein triggering described a plurality of addressable X-ray sources positions, to be performed the one or more X-ray sources position of launching so that pass the relevant range in the visual field spatially more contiguous or than other X-ray sources positions triggering more continually with respect to other X-ray source position that is triggered.
22. method as claimed in claim 7 also comprises:
Trigger a plurality of addressable X-ray source position of being roughly semicircular source so that one or more X-ray sources positions is skipped with pattern alternately between each triggers the X-ray source position, each X-ray source position emission X-ray when being triggered wherein, and wherein saidly be roughly semicircular source and completely or partially be arranged in the gap that is roughly semicircular or circle detection device array; And
The place produces corresponding signal in corresponding with each corresponding triggering of X-ray source position detector array, and wherein each corresponding signal is corresponding to the X-ray that incides described detector array and list.
23. as the method for claim 22, wherein triggering described a plurality of addressable X-ray sources positions, to be performed the one or more X-ray sources position of launching so that pass the relevant range in the visual field spatially more contiguous or than other X-ray sources positions being triggered more continually with respect to other X-ray sources position that is triggered.
24. as the method for claim 22, wherein trigger described a plurality of addressable X-ray sources positions with described alternately pattern, make the density of the relative X-ray position at recording projection data place increase and reduce across axial direction along described along the Z direction.
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| GB0525593D0 (en) | 2005-12-16 | 2006-01-25 | Cxr Ltd | X-ray tomography inspection systems |
| US8243876B2 (en) | 2003-04-25 | 2012-08-14 | Rapiscan Systems, Inc. | X-ray scanners |
| JP6122489B2 (en) * | 2012-06-05 | 2017-04-26 | ラピスカン システムズ、インコーポレイテッド | X-ray imaging device |
| CN103901057B (en) * | 2012-12-31 | 2019-04-30 | 同方威视技术股份有限公司 | Item inspection device using distributed X-ray sources |
| CN103340641B (en) * | 2013-04-27 | 2016-06-08 | 中国人民解放军北京军区总医院 | CT scanner Pulse Imageing system and Pulse Imageing method thereof |
| US9535186B2 (en) * | 2013-06-25 | 2017-01-03 | Analogic Corporation | Projection image generation via computed tomography system |
| WO2015053787A1 (en) * | 2013-10-11 | 2015-04-16 | Analogic Corporation | Tomosynthesis imaging |
| CN105361900B (en) * | 2014-08-26 | 2019-01-22 | 北京纳米维景科技有限公司 | Static CT imaging system and its image formation control method in real time |
| CN110680369B (en) * | 2019-09-18 | 2023-03-31 | 东软医疗系统股份有限公司 | Energy coding table compression method, query method, device and PET system |
| CN113133772A (en) * | 2020-01-20 | 2021-07-20 | 上海交通大学 | PET-CT system and scanning method |
| US11982780B2 (en) * | 2020-02-14 | 2024-05-14 | Siemens Medical Solutions Usa, Inc. | Helical PET architecture |
| CN114280087B (en) * | 2021-12-24 | 2024-04-09 | 北京航星机器制造有限公司 | CT imaging system and imaging method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5331553A (en) * | 1992-04-15 | 1994-07-19 | Ugm Medical Systems, Inc. | Three dimensional image reconstruction for a positron emission tomograph |
| CN1626039A (en) * | 2003-11-26 | 2005-06-15 | 通用电气公司 | Stationary computed tomography system and method |
| CN1689525A (en) * | 2004-04-28 | 2005-11-02 | 西门子公司 | Method for reconstructing projection data sets in dose-reduced segmented helical scans |
| CN1780585A (en) * | 2003-04-25 | 2006-05-31 | Cxr有限公司 | X-ray scanning system |
-
2007
- 2007-08-09 CN CN200780032561.8A patent/CN101512379B/en active Active
- 2007-08-09 CN CNA2007800325764A patent/CN101512380A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5331553A (en) * | 1992-04-15 | 1994-07-19 | Ugm Medical Systems, Inc. | Three dimensional image reconstruction for a positron emission tomograph |
| CN1780585A (en) * | 2003-04-25 | 2006-05-31 | Cxr有限公司 | X-ray scanning system |
| CN1626039A (en) * | 2003-11-26 | 2005-06-15 | 通用电气公司 | Stationary computed tomography system and method |
| CN1689525A (en) * | 2004-04-28 | 2005-11-02 | 西门子公司 | Method for reconstructing projection data sets in dose-reduced segmented helical scans |
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