CN102743182A - Method for improving fanned beam single photon emission computed tomography (SPECT) imaging resolution - Google Patents

Method for improving fanned beam single photon emission computed tomography (SPECT) imaging resolution Download PDF

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CN102743182A
CN102743182A CN2012100091783A CN201210009178A CN102743182A CN 102743182 A CN102743182 A CN 102743182A CN 2012100091783 A CN2012100091783 A CN 2012100091783A CN 201210009178 A CN201210009178 A CN 201210009178A CN 102743182 A CN102743182 A CN 102743182A
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resolution
projection
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fladellum
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CN102743182B (en
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温俊海
李翠芬
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Beijing Institute of Technology BIT
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Abstract

The invention provides a method for improving a fanned beam single photon emission computed tomography (SPECT) imaging resolution. On the premise that the size of a pore diameter of a collimator in a detector is not changed, a resolution of an SPECT image can be improved. The method includes that a detector can be used for swinging around a focal point, and also a plurality of detectors can be used for surrounding an object to be detected and can be arranged in a certain angle, a rotation measurement is performed in an angle of 2TT, according to a geometrical relationship between a fanned beam low resolution projection and a fanned beam high resolution projection, a relational matrix between a low resolution projection and a high resolution projection can be established, under each projection angle, a fanned beam high resolution projection can be obtained from low resolution projection data based on the relational matrix, and finally a high resolution SPECT image can be rebuilt by high resolution projection data through an analytic method or an iteration method.

Description

A kind of method that improves fladellum SPECT imaging resolution
Technical field
The present invention relates to a kind of SPECT imaging mode, especially do not change the method that improves imaging resolution under the prerequisite of the size of collimator aperture in the detector among the fladellum SPECT.
Background technology
(single photon emission computed tomography is a kind of nuclear medicine technology SPECT) to single photon emission tomographic imaging, has been widely used in the clinical diagnosis of disease at present.In SPECT, radioactive indicator is injected in the patient body, and SPECT can reconstruct radioactive indicator at the intravital scattergram of people, and this figure can reflect human tissue structure and movable function thereof, like the metabolism of blood flow state and human body.SPECT plays an increasingly important role at aspects such as diagnosing tumor and treatment monitorings.SPECT also is used in the skeleton image simultaneously and shows, the diagnosis of cardiovascular disease and brain diseases, and in recent years, SPECT also usually is used for the research of human brain cognitive activities.
In SPECT, the gamma-rays of tracer emission passes tissue and collimator, and device to be detected detects, and final the reconstruction obtains faultage image.What the aperture of collimator can not be done in the SPECT detector is too little, and it has limited the raising of SPECT device resolution.If the aperture size of collimator is too little, the γ photon numbers that then receives can influence the image quality of SPECT very little on the contrary.
Super-resolution rebuilding is to reconstruct high-definition picture from several low-resolution images.As a kind of effective method, it has been widely used in many fields, like medical imaging, and satellite image and Video Applications.In recent years, super-resolution rebuilding is applied to nuclear magnetic resonance, the CT imaging, and positron emission tomography and SPECT imaging are to improve image resolution ratio.But these methods are mainly used in image area or directional light backprojection reconstruction.In SPECT rebuild, the fladellum projection can improve the imaging resolution of SPECT, if fladellum backprojection reconstruction and super-resolution rebuilding combine, can improve the imaging resolution of SPECT to a great extent.
Summary of the invention
The present invention is directed to low this problem of SPECT imaging resolution, a kind of method that improves fladellum SPECT imaging resolution is provided, under the prerequisite that does not change collimator aperture size in the detector, improve the resolution of SPECT image.
Solve the problems of the technologies described above, the method for raising fladellum SPECT imaging resolution of the present invention may further comprise the steps:
The first step: center on body to be detected and angle to preset with a plurality of detectors;
Second step: detector rotation around the object center, rotate 2 π/M angle at every turn, on the position at its place, record a data for projection respectively, after measurement finishes, continue wheel measuring, M angle in 2 π scopes all measured and finished;
The 3rd step: according to the geometrical relationship between projection of fladellum low resolution and the projection of fladellum high-resolution, set up the relational matrix between low resolution projection and the high-resolution projection, the relation between two projections is: P L=RP H
P wherein LBe the data for projection that the low-resolution detection device measures, P HBe high-resolution data for projection to be tried to achieve, R is the relational matrix between projection of fladellum low resolution and the projection of fladellum high-resolution;
The 4th step:, try to achieve high-resolution projection according to projection and the definite relational matrix of the 3rd step that the second pacing amount obtains;
The 5th step: the data for projection of trying to achieve according to the 4th step can pass through analytic method, also can reconstruct high-resolution SPECT image through iterative method.
Adopt a plurality of detectors around body to be detected, with preset angle, wherein the pore size and the number of collimator is identical in each detector; Each detector corresponding focus equates to the distance at object center; Each detector corresponding focus equates to the distance of detector; Detector rotation around the object center, a plurality of detectors focus under same angle should coincide with a bit.
When a plurality of detectors focus under same angle overlapped, the position of each detector did not overlap, and an angle is arranged between them; The size of this angle is confirmed by following characteristic: the projection of the center of low-resolution detection device on transverse axis with respect to the center of imaginary high-resolution detector to the left and right respectively translation 0.5,1.5,2.5... high-resolution pixel.
Adopt a detector to realize the effect of a plurality of detectors around its Wobbing focus spot; Under each rotating and projection angle; Detector is also measured by preset angle swinging around its focus; The size of pendulum angle is confirmed by following characteristic: the projection of the center of low-resolution detection device on transverse axis with respect to the center of imaginary high-resolution detector to the left and right respectively translation 0.5; 1.5,2.5... high-resolution pixel.
Beneficial effect of the present invention:
The super-resolution image reconstruction that the present invention adopts is a research field of present awfully hot door, and it is to obtain a panel height image in different resolution from several low-resolution images.Several low-resolution images all are carried out to picture to same target, but exist sub-pix to move each other again, therefore include different information.The major advantage of this method is to use existing imaging device can obtain a high image of image resolution ratio that obtains than existing imaging device.
Description of drawings
Fig. 1 specifically realizes the flow chart of fladellum SPECT super-resolution imaging method for the present invention.
Fig. 2 is the distribution schematic diagram of the relation of the position between detector among the present invention and the body to be detected.
Fig. 3 is the position relation of a plurality of detectors focus under same angle when overlapping.
Fig. 4 is the relation between low-resolution detection device D1 and the high-resolution detector.
Fig. 5 is the relation between low-resolution detection device D2 and the high-resolution detector.
Fig. 6 is the relation between low-resolution detection device D3 and the high-resolution detector.
Fig. 7 is the relation between low-resolution detection device D4 and the high-resolution detector.
Fig. 8 is for ignoring detector thickness, the geometrical relationship between low-resolution detection device and the high-resolution detector.
Fig. 9 is the geometrical relationship (solid line is the low resolution projection, and dotted line is the high-resolution projection) of low resolution projection and high-resolution projection corresponding pixel points.
Figure 10 is low resolution and super-resolution reconstruction result contrast.
The specific embodiment
Be elaborated in the face of embodiment of the present invention down.
Fig. 1 specifically realizes the flow chart of fladellum SPECT super-resolution imaging method for the present invention.In the method, around body to be detected and with preset angle, also can use a detector to realize by preset angle swinging measurement with a plurality of detectors around focus.Here with 4 detectors, each detector resolution is that 32 pixels are that example describes, but does not explain that this invention only limits to these conditions, and scope related among the present invention only is defined by the claims.
The concrete putting position of detector is as shown in Figure 2; C is the central point of body to be detected; D1, D2, D3 and D4 are four identical detectors; Owing to be the fladellum imaging, then a focal position is all arranged with respect to each detector, F1, F2, F3 and F4 are respectively D1, D2, D3 and D4 corresponding focus among the figure.Position relation between them meets the following conditions: F1, F2, F3 and F4 equate that to the distance of object center C F1, F2, F3 and F4 and object center C line angulation are respectively 0, π/4,2 π/4,3 π/4.Detector D1, D2, D3 and D4 equate to the distance of its corresponding focus.Detector rotation around the object center; A plurality of detectors focus under same angle should coincide with a bit; Position relation between each detector is as shown in Figure 3, and D1, D2, D3 and D4 are D1, D2, D3 and the D4 among Fig. 2 among Fig. 3, and HD is imaginary high-resolution detector; It is arranged along X direction, also is the position at the high-resolution projection place of finally trying to achieve.For clearly finding out the position relation between the detector, Fig. 3 is split into Fig. 4, Fig. 5, Fig. 6 and four figure of Fig. 7, shown the position relation between D1, D2, D3 and D4 and the high-resolution detector respectively.The projection of the center of D1 on transverse axis with respect to the center of high-resolution detector to right translation 1.5 high-resolution pixel; The projection of the center of D2 on transverse axis with respect to the center of high-resolution detector to right translation 0.5 high-resolution pixel; The projection of the center of D3 on transverse axis with respect to the center of high-resolution detector to left 0.5 high-resolution pixel, the projection of the center of D4 on transverse axis with respect to the center of high-resolution detector to left 1.5 high-resolution pixel.
Step 103: detector rotation around the object center, rotate 2 π/M angle at every turn, a plurality of detectors record a data for projection respectively on the position at its place, after measurement finishes, continue wheel measuring, and M angle in 2 π scopes all measured and finished.
Under each projection angle; According to the geometrical relationship between projection of fladellum low resolution and the projection of fladellum high-resolution; Can be from many groups low resolution data for projection in the hope of the projection of fladellum high-resolution, the relation between projection of fladellum low resolution and the projection of fladellum high-resolution can be expressed as:
P L＝RP H
Wherein P L = L 1 L 2 L 3 L 4 , L 1, L 2, L 3, L 4Be the four groups of low resolution data for projection (not being four groups of low resolution data for projection that measure simultaneously) that under same angle, measure, L 1, L 2, L 3, L 4Dimension be 32, P HBe high-resolution projection matrix to be tried to achieve, its dimension is 128.R is the relational matrix between projection of fladellum low resolution and the projection of fladellum high-resolution,
Figure BDA0000130523390000042
Element r wherein IjA certain ray is to the contribution margin of low resolution projection in the projection of expression high-resolution.The method for solving of this contribution margin is (Fig. 8) as follows:
Low-resolution detection device D nThe coordinate of i pixel (ray) in its local coordinate system in (n=1,2,3,4) is x n(i).The coordinate of j pixel on transverse axis in the projection of g (j) expression high-resolution.d nBe low-resolution detection device D nThe coordinate of center projection on transverse axis, SDD is the focal length of detector.p n(j) be in the high-resolution detector j bar pixel (ray) at low-resolution detection device D nLocal coordinate system in coordinate position.With the high-resolution projection centre is zero, for any high-resolution projected bundle, can be got by the geometrical relationship among Fig. 8:
θ n＝arctan(d n/SDD)n＝1，2，3，4；
φ ( j ) = arctan ( g ( j ) SDD )
δ n(j)＝φ(j)-θ n
So
In Fig. 9, solid line is represented low resolution projected bundle, and dotted line is represented high-resolution projected bundle.Can get by geometrical relationship:
Figure BDA0000130523390000045
Wherein: Δ=[x (i+1)-x (i)]/2
Step 105: projection that measures by step 103 and the relational matrix between low resolution projection and the high-resolution projection, try to achieve the high-resolution projection with iterative method.Iterative process is following:
p H (0)Initial value at random
P H ( k + 1 ) = P H ( k ) + λ ( k ) P L ( i k ) - R T P H ( k ) | | R | | 2 R
Wherein subscript k representes iterations, and λ representes iteration step length.
The high-resolution data for projection of being tried to achieve by step 105 can pass through analytic method, also can reconstruct high-resolution SPECT image through iterative method.
Though more than described the specific embodiment of the present invention, the those of skill in the art in the present technique field should be appreciated that these only illustrate, and can make numerous variations or modification to these embodiments, and not deviate from principle of the present invention and essence.Scope of the present invention is only limited appended claims.

Claims (4)

1. a method that improves fladellum SPECT imaging resolution is characterized in that, may further comprise the steps:
The first step: center on body to be detected and angle to preset with a plurality of detectors;
Second step: detector rotation around the object center, rotate 2 π/M angle at every turn, on the position at its place, record a data for projection respectively, after measurement finishes, continue wheel measuring, M angle in 2 π scopes all measured and finished;
The 3rd step: according to the geometrical relationship between projection of fladellum low resolution and the projection of fladellum high-resolution, set up the relational matrix between low resolution projection and the high-resolution projection, the relation between two projections is: P L=RP H
P wherein LBe the data for projection that the low-resolution detection device measures, P HBe high-resolution data for projection to be tried to achieve, R is the relational matrix between projection of fladellum low resolution and the projection of fladellum high-resolution;
The 4th step:, try to achieve high-resolution projection according to projection and the definite relational matrix of the 3rd step that the second pacing amount obtains;
The 5th step: the data for projection of trying to achieve according to the 4th step can pass through analytic method, also can reconstruct high-resolution SPECT image through iterative method.
2. a kind of method that improves fladellum SPECT imaging resolution as claimed in claim 1 is characterized in that wherein the pore size and the number of collimator is identical in each detector; Each detector corresponding focus equates to the distance at object center; Each detector corresponding focus equates to the distance of detector; Detector rotation around the object center, a plurality of detectors focus under same angle should coincide with a bit.
3. a kind of method that improves fladellum SPECT imaging resolution as claimed in claim 2 is characterized in that, when a plurality of detectors focus under same angle overlapped, the position of each detector did not overlap, and an angle is arranged between them; The size of this angle is confirmed by following characteristic: the projection of the center of low-resolution detection device on transverse axis with respect to the center of imaginary high-resolution detector to the left and right respectively translation 0.5,1.5,2.5... high-resolution pixel.
4. a kind of method that improves fladellum SPECT imaging resolution as claimed in claim 1 is characterized in that, realizes the effect of a plurality of detectors around its Wobbing focus spot with a detector; Under each rotating and projection angle; Detector is also measured by preset angle swinging around its focus; The size of pendulum angle is confirmed by following characteristic: the projection of the center of low-resolution detection device on transverse axis with respect to the center of imaginary high-resolution detector to the left and right respectively translation 0.5; 1.5,2.5... high-resolution pixel.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107157505A (en) * 2017-06-09 2017-09-15 北京理工大学 A kind of method for improving pencil-beam SPECT imaging resolutions
CN110428370A (en) * 2019-07-01 2019-11-08 北京理工大学 A kind of method that utilization is eccentrically rotated raising pencil-beam SPECT imaging resolution

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991000048A2 (en) * 1989-06-30 1991-01-10 Kaplan H Charles Transmission/emission registered image (teri) computed tomography scanners
JPH11295243A (en) * 1998-04-14 1999-10-29 Hitachi Ltd X-ray ct scanner apparatus
US20020076088A1 (en) * 2000-12-15 2002-06-20 Kun-Cheng Tsai Method of multi-level facial image recognition and system using the same
CN1620989A (en) * 2003-11-24 2005-06-01 西门子公司 Method for production of tomographic section images of a periodically moving object with a number of focus detector combinations
CN101615290A (en) * 2009-07-29 2009-12-30 西安交通大学 A kind of face image super-resolution reconstruction method based on canonical correlation analysis
CN102106740A (en) * 2011-03-11 2011-06-29 河海大学 X-ray compound tomoscanning imaging system and method
CN102177528A (en) * 2008-10-10 2011-09-07 皇家飞利浦电子股份有限公司 High contrast imaging and fast imaging reconstruction

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991000048A2 (en) * 1989-06-30 1991-01-10 Kaplan H Charles Transmission/emission registered image (teri) computed tomography scanners
JPH11295243A (en) * 1998-04-14 1999-10-29 Hitachi Ltd X-ray ct scanner apparatus
US20020076088A1 (en) * 2000-12-15 2002-06-20 Kun-Cheng Tsai Method of multi-level facial image recognition and system using the same
CN1620989A (en) * 2003-11-24 2005-06-01 西门子公司 Method for production of tomographic section images of a periodically moving object with a number of focus detector combinations
CN102177528A (en) * 2008-10-10 2011-09-07 皇家飞利浦电子股份有限公司 High contrast imaging and fast imaging reconstruction
CN101615290A (en) * 2009-07-29 2009-12-30 西安交通大学 A kind of face image super-resolution reconstruction method based on canonical correlation analysis
CN102106740A (en) * 2011-03-11 2011-06-29 河海大学 X-ray compound tomoscanning imaging system and method

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
NHAT NGUYEN等: "Ehhicient Generalized Cross-Validation with Applications to Parametric Image Restoration and Resolution Enhancement", 《IEEE TRANSACTIONS ON IMAGE PROCESSING》 *
SUNNY CHEOL PARK等: "Super-Resolution Image Reconstruction:Atechnical Overview", 《IEEE SIGNAL PROCESSING MAGAZINE》 *
唐丽焕: "基于迭代条件模型算法的图像超分辨率重建", 《计算机工程与应用》 *
姚屏: "图像的超分辨率处理方法研究现状", 《半导体光电》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107157505A (en) * 2017-06-09 2017-09-15 北京理工大学 A kind of method for improving pencil-beam SPECT imaging resolutions
CN107157505B (en) * 2017-06-09 2019-10-18 北京理工大学 A method of improving pencil-beam SPECT imaging resolution
CN110428370A (en) * 2019-07-01 2019-11-08 北京理工大学 A kind of method that utilization is eccentrically rotated raising pencil-beam SPECT imaging resolution

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