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锥束CT直接三维成像算法研究
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摘要
CT(Computed Tomography X射线计算机断层摄影术)自1972年问世以来得到了越来越广泛的应用。CT的广泛应用反过来又推动了对它的研究,使它得到进一步的发展,在30年的发展过程中,它基本上经历了6次大的变革。CT的这些发展变化主要体现在两个方面,一是提高扫描速度,二是改善图像的质量。
     CT的断层图像是由计算机对物体的投影数据进行计算而获得的,因此CT的成像过程可以分为两大步,一是用X光系统进行投影数据的测量,获得充分的投影数据;二是用计算机对投影数据进行计算来获得断层图像。X光的投影测量结构可以分为三种,分别为平行束投影、扇束投影和锥束投影。平行束投影在工程上是不能直接实现的。和扇束投影相比,锥束投影一次性获得的信息量更大,因此锥束投影结构有利于提高扫描速度和图像质量。但是锥束投影数据和断层图像之间的关系很复杂,这会使计算的复杂度大大增加。近十年来,出现了很多针对锥束CT的研究,但基本上都不是很成熟,到目前为止还没有出现真正意义上的商业化锥束CT。针对锥束CT目前存在的主要问题,本文的主要研究內容有四点:
     (一)结合锥束扫描的特点提出了一种中间函数重建算法。中间函数重建算法是一种基于傅立叶空间的精确解析算法,同时它也是一种反投影算法。它的基本算法思想是先对探测器采集到的数据进行傅立叶变换,得到一个中间函数;接下来是对中间函数的形式进行变换,找到它和图像函数傅立叶变换之间的关系,因此可以通过对这个变形的中间函数进行反投影而重建出图像。本文也利用实验对算法进行了验证。
     (二)研究了锥束扫描时的直接三维重建技术。三维图像在医学领域得到越来越重要的应用,它可以帮助医生准确地进行病灶定位和确定手术方案。传统的CT三维图像是通过对二维断层图像进行后处理而获得的,主要是通过插值计算的方法来获得三维空间点。由于传统CT在z轴方向采集的间隔比较大,因而Z轴的分辨率比较低,再加上慢速扫描带来的z轴运动伪影,这样就使重建出的三维图像质量也比较差。直接三维重建是利用锥束投影时获得的大量数据,直接进行三维空间点的计算,然后再使用三维绘制技术来获得三维图像。由于
Since the birth of the first CT (computed tomography) scanner in 1972, CT has been widely used in the world. The wide uses of CT also generate great impetus for CT research. Several big changes have taken placed during the past 30 years. These changes mainly involve in two aspects- speed and image quality.The CT image is calculated from projection data by computer. So there are two steps to get image—using X-ray to measure projection data and calculating projection data to get image. There are three kinds of X-ray measure structures, parallel-beam, fan-beam and cone-beam. But the parallel-beam can not be realized directly in engineering. Compared with fan-beam, cone-beam projection system can gain more information in one projection, so it is of advantage to increasing scanning speed and image quality. But the relationship between cone-beam projection data and the cross section image is very complex. Accordingly the reconstruction algorithm and scan frame becomes more complex. In recent years, many scholars have researched the cone-beam scan technology, but the algorithms they developed are not very perfect, so the real commercial cone-beam CT is not appeared today. In order to solve the problem in cone-beam CT, Four main questions of cone-beam CT have been researched in this thesis.1. An intermediate function algorithm, which can be used in cone-beam CT, have been researched. It is a kind of exact resolution algorithm which is based on Fourier space, and at same time it is a kind of back-projection algorithm. The algorithm can be decomposed into three steps. Firstly, a partial Fourier transform is applied to the projection data and an intermediate function is got. Secondly, the same changes to the intermediate function are made and a form of inverse Fourier transform of object function is got. Finally, the image can be reconstructed by making back-projection to the new form of intermediate function. To verify the algorithm, some experiments have been done and the results are satisfied.2. Direct 3-D reconstruction technology has been researched. The using of 3-D image becomes more and more important in medical field. It can help doctor to find
    an exact place of focus and to make plan for operation. Three-dimension image of traditional CT is made from 2-D image by late processing. The main method of processing is an interpolating calculation. Because of no enough sampling in z axes, the image space resolution of traditional CT is low. Traditional CT also has motive artifact which is resulted from low scan speed. These restrictions make the quality of 3-D image of traditional CT not satisfied. Direct 3-D reconstruction is done by using a lot of cone-beam projection data. A 3-D image can be got by directly calculating the value of 3-D space points. The 3-D points which are gained by direct reconstruction have same resolution in three directions, so the 3-D image which is based on these points has a same nature in all direction.3. By Researching data sufficient condition of VOI reconstruction, a new scan framework is designed to adapt the algorithm. The new framework is named double cone-beam three axes scan. The idea of three axes scan is an extending of spiral scan. The sample density in z direction will decrease when the pitch increases in fast scan. Double cone-beam framework, which can increase the sample density in z direction, uses two different focuses to produce two cone-beams in different place. Two focuses turn on alternation to avoid overlap of projection data. To fulfill this work mode, a kind of double anode tube is put forward in this paper.4. A new scan method which can be used in heart scan is designed. The scan structure is a double cone-beam three axes scan. General CT can not get heart's stationary image, because the heart is a fast moving organ. Three-dimension image of heart can be got directly by combining double cone-beam three axes scan technology and direct 3-D reconstruction algorithm.In this thesis, some other cone-beam scan reconstruction algorithms are also analyzed. These algorithms can be sorted by exactness, the length of object and scan mode. Every algorithm has its' virtue and limitation. Algorithms which are discussed in this paper are FDK, Grangeat, PI and PHI etc.
引文
[1] http://www.medical.siemens.corn/webapp
    [Axelsson 1994] Axelsson C and Daniellsson P E, "Three-dimensional reconstruction from cone-beam data in O(N3 log N) time. " Phys Med Biol 1994, 39:477-491
    [Chen2003a] Guang-Hong Chen, "New framework of image reconstruction: Fan beam, " Medical Physics, vol. 30(6), June 2003
    [Chen2003b] Guang-Hong Chen, "An alternative derivation of Katsevich's cone-beam reconstruction formula, " Medical Physics, vol. 30(12), December 2003
    [Clack 1994] R Clack and M Defrise, "Overview of reconstruction algorithms for exact cone-beam tomography, " Proc. SPIE 2299, 230 241 1994
    [Danielsson 1997a] Danielsson P E, Edholm P, Eriksson J and Magnusson S M, "Towards exact reconstruction for helical cone-beam scanning of long object, A new detector arrangement and a new completeness condition, " Proc. 1997 Meeting on fully 3d image reconstruction in radiology and nuclear medicine.
    [Danielsson 1997b] Danielsson P E, "Iterative Techiques for Projection and Back-Projection", Technical Report LiTH-ISY-R- 1960, ISSN 1400-3902.
    [Danielsson 1997c] Danielsson P E, P Edholm, J Eriksson, and M Magnusson-Seger, "Towards Exact 3D-reconstruction for Helical Cone-Beam Scanning of Long Objects: A New Arrangement and a New Completeness Condition, " In International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, June 25-28, 1997, Nemacolin, Pennsylvania, USA, 141 144.
    [Danielsson 1997d] Danielsson P E and M Ingerhed, "Backprojection in (N~2Log_2N) time, "In IEEE Medical Imaging, Nov 13 15, 1997, Alberquerque, New Mexico, US
    [Danielsson 1998] Danielsson, P E, P Edholm, J Eriksson, M Magnusson-Seger, and H. Turbell, "Helical Cone-Beam Scanning and Reconstruction of Long Objects Using 180 Degrees Exposure", Patent Application PCT/SE 98/00029, Filed 13 January 1998.
    [Defrise1994] M Defrise and R Clack, "A cone-beam reconstruction algorithm using shift variant filtering and cone-beam backprojection, " IEEE Trans. Med. Imaging 13, 186 195 1994.
    [Defrise1997] M Defrise, and F Noo, "Reconstruction of truncated cone-beam projections using the frequency-distance relation, "In International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, June 25-28, 1997, Nemacolin, Pennsylvania, USA, 32 35.
    [Defrise1997] M Defrise, F Noo and H Kudo, "Quasi-Exact Region-of-Interest Reconstruction from Helical Cone-Beam Data, " In IEEE Medical Imaging, 1999, Seattle, Washington, USA, Volume 2, 1101 1103.
    [Defrise2000] M Defrise, F Noo and H Kudo, "A solution to the long-object problem in helical cone-beam tomography, "Phys. Med. Biol 2000, 45, 623-643
    [Eberhard 1995] J Eberhard and K C Tam, "Helical and Circle Scan Region of Interest Computerized Tomography, "US Patent 5, 463, 666, Oct. 31.
    [Edholm1986] P Edholm R M Lewitt and B Lindholm, "Novel Properties of the Fourier Decomposition of the Sinogram, " In Int. Workshop on Physics and Engineeing of Computerized Multidimensional Imaging and Processing, Proc. of the SPIE, Volume 67(1), 8 18.
    [Edholm1987] Edholm P R and Herman G T, "Linograms in image reconstruction from projections", IEEE Trans Med Imag 1987, vol 6, 301-307
    [Feldkamp 1984] L A Feldkamp, L C Davis, and J W Kress, "Practical cone beam algorithm, " J. Opt. Soc. Am. A 1, 612 619 1984
    [Foley 1990] J Foley, A van Dam, S Feiner and J Hughes , "Computer Graphics: principles and practice ", AddisonWesley.
    [Goertzen2000] A L Goertzen, F J Beckman and S R Cherry, "Effect of voxel size in CT simulations", In IEEE Medical Imaging, Oct 16 20, 2000, Lyon, France
    [Grangeat 1991] P. Grangeat, "Mathematical framework of cone beam 3D reconstruction via the first derivative of the Radon transform, " in Mathematical Methods in Tomography, Lecture Notes in Mathematics, New York, 1991, Vol. 1497, pp. 66 97.
    [Grangeat 1991] P. Grangeat, P. Le Mason, P. Melennec, and P. Sire, Evaluation of the 3D Radon Transform Algorithm for Cone Beam Reconstruction, In SPIE Medical Imaging V: Image Processing, Technical Conference 1445, Feb. 23 -March 1, 1991, San Jose, Califomia, USA.
    [Grass 2000a] M Grass, T K ohler and R Proksa, "3D cone-beam CT reconstruction for circular trajectories, " Physics in Medicine and Biology 45(2), 329 347. 2000
    [Grass 2000b] M Grass, T K ohler and R Proksa, " Weighted hybrid cone beam reconstruction for circular trajectories, "In IEEE Medical Imaging, Oct 16 20, 2000, Lyon, France.
    [Gullberg 1992] G T Gullberg and G L Zeng, "A cone-beam filtered backprojection reconstruction algorithm for cardiac single photon emission computed tomography, "IEEE Trans. Med. Imaging 11, 91-101, 1992.
    [G. Wang 1993] G Wang, T H Lin, P Cheng, and D M Shinozaki, "A general cone beam reconstruction algorithm, " IEEE Trans. Med. Imaging 12, 486 496 1993
    [G. Wang 1994] G Wang, Y Liu, T H Lin, and P C Cheng, "Half-scan cone-beam x-ray micro tomography formula, "Scanning 16, 216-220, 1994.
    [G. Wang 2002] G Wang, H Liu, "Generalized Feldkamp image reconstruction from equiangular cone-beam projection data, "Proceedings of 13th IEEE symposium on 2000, CBMS 123-128
    [G. Wang 2002] G Wang, C R Crawford and W A Kalender, "Multirow detector and cone beam spiral/helical CT, " IEEE Trans. Med. Imaging 19, 817-821, 2000
    [G Wang2005] Yangbo Y, G Wang, "Filtered backprojection formula for exact image reconstruction from cone-beam data along a general scanning curve, " Medical Physics, vol. 32(1), January 2005
    [何晖光2002] 何晖光,田捷,赵明昌,杨骅,“基于分割的三维医学图像表面重建算法”,软件学报,2002,Vol,13,No.2.
    [Herman 1977] Herman G T and A Naparstek, " Fast image reconstruction based on a radon inversion formula appropiate for rapidly collected data, "SIAM Journal of Applied Mathematics 33, 511 533
    [Herman1980] Herman G T, " Image reconstruction from projections - the fundamentals of computerized tomography, "Academic Press, New York. ISBN 0-12-342050-4.
    [Heuscher1999] Heuscher D, "Helical cone beam scans using oblique 2D surface reconstruction, "In International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, June 23 26, 1999, pp. 204 207.
    [Heuscher2004] D Heuscher, K Brown and F Noo, "Redundant data and exact helical cone-beam reconstruction, " Phys. Med. Biol. 49, 2219 2238 2004
    [Hui Hu 1998] Hui H, H David H, Stan F, Sholom A, Gary S and George S, "Multi-slice helical CT: Principles, Imaging Characteristics, And Performance", Proceedings of the 20th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1998, vol 20, 637-639
    [Hui Hu 1999] Hui Hu, "multi-slice helical CT scan and reconstruction, " Med Phys. 1999, 26 (1), 5-18,
    [Ingerhed1998] Ingerhed M and Danielsson P E, "Implementation of Backprojection in O(N~2Log_2N) Time, " In SSAB Symposium on Image Analysis, March 16 17, 1998, Uppsala, pp. 25 28. Swedish Society for Automated Image Analysis. ISSN 1100-6641.
    [Ingerhed1999] Ingerhed M, "Fast Backprojection in Computed Tomography: Implementation and Evaluation, " Licentiate Thesis No 760. Department of Electrical Engineering, Linkoping University. ISBN 91-7219-462-6, ISSN 0280-7971.
    [Jacobson 1996] Jacobson C, "Fourier Methods in 3D-Reconstruction from Cone-Beam Data, " Ph. D. thesis, Department of Electrical Engineering, Link oping University.
    [Joseph1982] Joseph P M, "An Improved Algorithm for Reprojecting Rays Through Pixel Images, "IEEE Transactions on Medical Imaging MI- 1, 192 196.
    [Kachelriess 2000a] Kachelriess M and W Kalender, "Advanced Single-Slice Rebinning (ASSR) and Misalignment Correction for Large Cone-Beam Spiral CT", In RSNA'00, Nov. 26 -Dec 1, Chicago, USA, supplement to Radiology, volume 217 pp. 405.
    [Kachelriess 2000b] Kachelriess M, Schaller S, and Kalender W, "Advanced Single-Slice Rebinning in Cone-Beam Spiral CT", Medical Physics 27(4), 754 772.
    [Kachelriess 2000c] Kachelriess M, Schaller S, and Kalender W, "Advanced Single-Slice Rebinning in Cone-Beam Spiral CT: Theoretical considerations and medical applications, " In SPIE Medical Imaging, Feb. 12 17, 2000, San Diego, California, USA, pp. 494 505.
    [Kak1987] A C Kak and M Slaney , "Principles of Computerized Tomographic Imaging, " IEEE Press. ISBN 0-87942-198-3.
    [Kalender1995] Kalender W, "Principles and performance of spiral CT", In L. W. Goldman and J. B. Fowlkes (Eds. ), Medical CT and Ultrasound: Current Technology and Applications, pp. 379 410. Advanced Medical Publishing. ISBN 1-883526-03-5.
    [Kalender2000] Kalender W, "Computed Tomography: Fundamentals, System Technology, Image Quality, Applications, "Publics MCD Verlag. ISBN 3-89578-081-2.
    [Katsevich 2002a] A Katsevich, "Theoretically exact filtered backprojection-type inversion algorithm for Spiral CT, " SIAM ~Soc. Ind. Appl. Math. J. Appl. Math. 62, 2012 2026 2002.
    [Katsevich 2002b] A Katsevich, "Analysis of an exact inversion algorithm for spiral cone beam CT, " Phys. Med. Biol. 47, 2583 2597, 2002.
    [Katsevich 2003] A Katsevich, "A general scheme for constructing inversion algorithm for cone beam CT, " Int. J. Math. Math. Sci. 21, 1305 1321 2003.
    [Katsevich 2004] A Katsevich, "On two versions of a 3π algorithm for spiral CT , "Phys. Med. Biol. 49, 2129 2143 2004
    [Kohler2000a] T K ohler, R Proksa and M Grass, "A Fast and Efficient Method for Sequential Cone-Beam Tomography", In IEEE Medical Imaging, Oct 16 20, 2000, Lyon, France.
    [Kohler2000b] T K ohler, H Turbell and M Grass, "Efficient Forward Projection Through Discrete Data Sets Using Tri-Linear Interpolation", In IEEE Medical Imaging, Oct 16 20, 2000, Lyon, France.
    [Kreuder1999] F Kreuder, M Grass, V Rasche, H Braunisch, and O D ossel, "Fast calculation of the X-ray transform from the radial derivative of the 3D Radon transform using gridding and fast backprojection techniques", In European Medical and Biological Engineering Conference, Vienna, Nov. 4 7.
    [Kudo1990] H Kudo and T Saito, "Feasible cone beam scanning methods for exact reconstruction in three-dimensional tomography", J. Opt. Soc. Am. A, 1990, vol 7, 2169-2183
    [Kudo1991] H Kudo and T Saito, "Helical-scan computed tomography using cone-beam projections, " IEEE Nuclear Science Symposium and Medical Imaging conference 1991, conference record of the 1991 IEEE, 2-9 Nov 1991 pp:1958-1962
    [Kudo 1994] H Kudo and T Saito, "Derivation and implementation of a cone-beam reconstruction algorithm for non-planar orbit, " IEEE Trans. Med. Imaging 13, 196 211 1994.
    [Kudo 1996] H Kudo and T Saito, "Extended Cone-Beam Reconstruction Using Radon Transform", IEEE Nuclear Science Symposium 1996, Conference Record, vol 3, 1693-1697
    [Kudo 1998] H Kudo F Noo and M Defrise, "Cone-Beam filtered-backprojection algorithm for truncated helical data", Phys. Med. Biol. 1998, 43, 2885-2909
    [Kudo 1999] H Kudo, S Park, F Noo and M Defrise, "Performance of quasi-exact cone-beam filtered back projection algorithm for axially truncated helical data", IEEE Trans Nuc Sci 1999, vol 46, 608-617
    [Kudo 2000] H Kudo, F Noo and M Defrise, "Quasi-exact filtered backprojection algorithm for long-object problem in helical cone-beam tomography, " IEEE Trans Med Imag, 2000, vol 19, 902-921
    [Lanzavecchia 1996] S Lanzavecchia, and P L Bellon, "Electron tomography in conical tilt geometry, The accuracy of a direct Fourier method (DFM) and the suppression of non-tomographic noise, " Ultramiscoscopy 63, 247 261.
    [Larson 1998] G L Larson, C C Ruth and C R Crawford, "Nutating slice CT image reconstruction, " Patent ApplicationWO 98/44847. 174
    [Lee 2002] S W Lee, G Cho and G Wang, "Artifacts associated with implementation of the Grangeat formula, " Med. Phys. 29, 2871-2880, 2002
    [Lee2003] S W Lee and G Wang, "A Grangeat-type half-scan algorithm for cone-beam CT" Med. Phys. 30. 4., April 2003
    [Lewitt1990] R M Lewitt, "Multidimensional digital image representations using generalized Kaiser-Bessel window functions", Journal of the Optical Society of America 7(10), 1834 1846.
    [Lewitt1992] R M Lewitt, "Alternatives to voxels for image representation in iterative reconstruction algorithms", Physics in Medicine and Biology 37, 705 716.
    [Marr1981] Marr, R. B., C. Chen, and P. C. Lauterbur, "On two approaches to 3D reconstruction in NMR zeugmatography", In G. T. Herman and F. Natterer (Eds. ), Mathematical Aspects of Computerized Tomography, Oberwolfach (FRG), Lecturer Notes in Mathematics, pp. 225 240. Springer Verlag.
    [Muller 1996] Muller M J, "Simulation of X-ray Projections for Experimental 3D Tomography". Technical Report LiTH-ISY-R-1866, ISSN 1400-3902, Image Processing Lab, Department of Electrical Engineering, Link"oping University.
    [Mueller1998] Mueller K, "Fast and accurate three-dimensional reconstruction from cone beam projection data using algebraic methods", Ph. D. thesis, The Ohio State University, USA.
    [Mueller1999] Mueller K, Yagel R, and Wheller J, "Fast Implementation of Algebraic Methods for Three-Dimensional Reconstruction from Cone-Beam Data", IEEE Transactions on Medical Imaging 18(6), 538 548.
    [Natterer1986] Natterer F , "The Mathematics of Computerized Tomography", John Wiley and Sons. ISBN 0-471-90959-9.
    [Nilsson1996] Nilsson S , "Fast Backprojection", Technical Report LiTH-ISY-R-1865, ISSN 1400-3902, Department of Electrical Engineering, Link"oping University.
    [Nilsson1997] Nilsson S , "Application of Fast Backprojection Techniques for Some Inverse Problems of Integral Geometry", Ph. D. thesis, Department of Mathematics, Link"oping University. No. 499.
    [Noo 1998] F Noo, H Kudo and M Defrise, "Approximate Short-Scan Filtered Backprojection for Helical CB Reconstruction", In IEEE Medical Imaging, Nov8 14, 1998, Toronto, Canada.
    [Noo 2002a] F Noo, "Image reconstruction from cone-beam data on a circular short-scan", SPIE Medical Imaging, San Diego, CA, 2002.
    [Noo 2002b] F Noo, M Defrise, R Clackdoyle and H Kudo, "Image reconstruction from fan-beam projections on less than a short sacn" Phys. Med. Biol. 47(2002) 2525-2546
    [Pan2000] T Pan and Y Shen, "New Multi-sector Reconstruction for Cardiac CT", In IEEE Medical Imaging, Oct 16 20, 2000, Lyon, France.
    [Parker 1982] D L Parker, "Optimal short scan convolution reconstruction for fan-beam CT, " Med. Phys. 9, 254-257, 1982
    [Proksa2000] R Proksa, T Kohler, M Grass, and J Timmer, "The n-PI-method for helical cone-beam CT, " IEEE transactions on medical imaging, vol 19(9), 848-863
    [Rizo1991] P Rizo, P. Grangeat, P Sire, P L Mason and P Melennec , "Comparison of two three-dimensional X-ray cone-beam reconstruction algorithms with circular source trajectories", Journal of the Optical Society of America 8(10), 1639 1648.
    [Seger1993] M Seger, "Linogram andOtherDirect FourierMethods for Tomographic Reconstruction", Ph. D thesis, Department of Electrical Engineering.
    [Schaller1996] S Schaller, T Flohr and P Steffen, "A New Approximate Algorithm for Image Reconstruction in Cone-Beam Spiral CT at Small Cone-Angles", In IEEE Medical Imaging, Anaheim, California, USA.
    [Schaller1997] S Schaller, T Flohr and P Steffen, "New, Efficient Fourier-reconstructionMethod for Approximate Image Reconstruction in Spiral Cone-Beam CT at Small Cone Angles", In SPIE Medical Imaging, Newport Beach, California, USA
    [Schaller1998a] S Schaller , "Practical Image Reconstruction for Cone Beam Computed Tomography", Ph. D thesis, Friedrich-Alexander-Universit"at Erlangen-N" umberg, Germany.
    [Schaller 1998b] S Schaller, T Flohr, H Wolf and W Kalender, "Evaluation of a Spiral Reconstruction Algorithm for Multirow-CY", In RSNA'98, Nov. 29-Dec 4, Chicago, USA, supplement to Radiology, volume 209 (P).
    [Schaller1998c] S Schaller, M Karolczak, K Engelke, K Wiesent and W. Kalender, "Implementation of a Fast Cone-Beam Backprojection Algorithm for Microcomputed Tomography (HCT) Using Homogeneous Coordinates", In RSNA'98, Nov. 29-Dec 4, Chicago, USA, supplement to Radiology, volume 209 (P).
    [Schaller1999] S Schaller, F Noo, F Sauer, K C Tam, G Lauritsch and T Flohr, "Exact Radon rebinning algorithms using local region-of-interest for helical cone beam CT". In International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and NuclearMedicine, June 23 26, 1999, Egmond aan Zee, The Netherlands, pp. 11 14.
    [Schaller2000] S Schaller, F Noo, F Sauer, K C Tam and T Flohr, "Exact Radon Rebinning Algorithm for the long object problem in helical Cone-Beam CT", IEEE Trans Med Imag, vol 19, No 5, May 2000, 361-375
    [Schomberg 1995] H Schomberg and J Timmer, "The Gridding Method for Image Reconstruction by Fourier Transformation", IEEE Transactions onMedical Imaging 14(3), 596 607.
    [Sedarat2000] H Sedarat and D G Nishimura, "On the optimality of the gridding reconstruction algorithm", IEEE Transactions on Medical Imaging 19(4), 406 317.
    [Siddon 1985] R L Siddon, "Fast calculation of the exact radiological path length for a three-dimensional CT array", Medical Physics 12, 252 255.
    [Silver1997] M D Silver, "Practical Limits to High Helical Pitch, Cone-Beam Computed Tomography", In InternationalMeeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, June 25-28, 1997, Nemacolin, Pennsylvania, USA, pp. 44 47.
    [Silver1998] M D Silver, "High-Helical-Pitch, Cone-Beam Computed Tomography", Physics in Medicine and Biology 43(4), 847 855.
    [Sourbelle2000] K Sourbelle, G Lauritsch, K C Tam, F Noo and W Kalender, "Performance evaluation of local ROI algorithms for exact ROI reconstruction in spriral cone-beam computed tomography", In IEEE Medical Imaging, Oct16 20, 2000, Lyon, France.
    [Smith 1985] B D Smith, "Image reconstruction from cone-beam projections: Necessary and sufficient conditions and reconstruction methods", IEEE Trans. Med. Imag MI-4, 14 25 1985.
    [Taguchi 1998] K Taguchi and H Aradate, "Algorithm for image reconstruction in multi-slice helical CT", Medical Physics 25(4), 550 561.
    [Tam 1995a] K C Tam, "Three-Dimensional Computerized Tomography Scanning Method and System for Large Objects with Smaller Area Detectors", US Patent 5, 390, 112, Feb. 14.
    [Tam 1995b] K C Tam, "Helical and circle scan region of interest computerized tomography, " U. S. Pat. 5 463 666, OCT. 31, 1995
    [Tam 1997] K C Tam, S Samarasekera and F Sauer, "Exact Cone-Beam CT with a Spiral Scan", In International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, June 25-28, 1997, Nemacolin, Pennsylvania, USA.
    [Tam 1998a] K C Tam, S Samasekera and F Sauer, "Region-of interest cone beam CT with a spiral scan, " in SPIE, vol. 3336, 1998, pp:274-283
    [Tam 1998b] K C Tam, S Samasekera and F Sauer, "Exact cone beam CT with a spiral scan, "Phys. Med. Biol 1998, vol. 43, pp:1015-1024
    [Tam 2000] K C Tam, G Lauritsch, K sourbelle, F Sauer and B Ladendorf, "Exact (spiral +Circles) Scan Region-of-Interest Cone Beam Reconstruction via Backprojection", IEEE Trans Med. Imag, vol 19, no. 5, May 2000
    [Turbel1998] Turbell H and Danielsson P E, "The PI Method -Non-Redundant Data Capture and Efficient Reconstruction for Helical Cone-Beam CT", In IEEE Medical Imaging, Nov 8 14, 1998, Toronto, Canada.
    [Turbel1999a] Turbell H, "Three-Dimensional Image Reconstruction in Circular and Helical Computed Tomography". Licentiate Thesis. Department of Electrical Engineering, Link"oping University. ISBN 91-7219-463-4, ISSN 0345-7524.
    [Turbel1999b] Turbell H and Danielsson P E, "An improved PI-method for reconstruction from helical cone-beam projections", In IEEE Medical Imaging, 1999, Seattle, Washington, USA.
    [Turbel1999c] Turbell H and Danielsson P E, "Fast Feldkamp Reconstruction", In International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, June 23 26, 1999, Egrnond aan Zee, The Netherlands, pp. 311 314.
    [Turbel2000] Turbell H and Danielsson P E, "Helical Cone-Beam Tomography", International Journal of Imaging Systems and Technology 11(1), 91 100.
    [Tuy 1983] H K Tuy, "An inverse formula for cone-beam reconstruction, " SIAM~Soc. Ind. Appl. Math. J. Appl. Math. 43, 546 552 1983
    [Xiaohui 1999] Xiaohui Wang and Ruola Ning, "A cone-beam Reconstruction Algorithm for Circle-Plus-Arc Data-Acquisition Geometry", IEEE Trans Med Imag 1999, vol. 18, no. 9, 815-824
    [Yu2004] Hengyong Yu, Ge Wang, "Feldkamp-type VOI reconstruction from super-short-scan cone-beam data" Med. Phys. 31(6) June 2004.
    [Zhao 2000] S Zhao and G Wang, "Feldkamp-type cone-beam tomography in the wavelet framework, " IEEE Trans. Med. Imaging 19, 922-929, 2000
    [Zeng1992] G L Zeng and G T Gullberg, "A cone-beam tomography algorithm for orthogonal circle-and-line orbit, " Phys. Med. Biol. 37, 563 577 1992
    [Zeng 1994] G L Zeng, R Clark, and G T Gullberg, "Implementation of Tuy's inversion formula, "Phys. Med. Biol. 39, 493 507 1994.
    [曾凯2003] 曾凯,陈志强,“三维锥形束CT解析重建算法发展综述”,中国体视学与图像分析,2003年6月 第8卷 第2期
    [赵强2000] 赵强,《医学影像设备》第二军医大学出版社 2000年12月 第一版
    [张贤达1998] 张贤达,保铮,《非平稳信号分析与处理》国防工业出版社 1998年9月第1版

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