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锥束CT圆轨迹半覆盖扫描的几何校正 被引量:3

Geometric calibration for half-cover scanning in circular cone-beam CT
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摘要 研究了一种高精度的几何校正方法用于对锥束CT圆轨迹半覆盖成像进行几何校正。首先,使用Otsu算法分割体模投影中钢球所在的区域,并计算质心坐标。然后,采用最小二乘算法对质心进行椭圆拟合,并根据椭圆参数采用Cho的全覆盖几何校正算法计算探测器的旋转角度。最后,顺时针旋转质心,求得旋转的角度后,再次进行椭圆拟合,并根据得到的椭圆参数采用Noo的全覆盖几何校正算法计算除探测器倾斜角之外的所有几何参数。实验结果表明:探测器旋转角和偏转角的测量精度分别为0.02°和0.01°;射线源到探测器和到旋转轴的距离的测量精度分别为0.05mm和0.01mm;射线源在探测器上投影坐标的计算精度分别为0.07mm和0.15mm。由得到的结果可知,所提出的校正方法有效地去除了几何伪影的干扰,满足半覆盖成像图像重建的要求。 A high-precision method was investigated to realize the geometric calibration of half-cover scanning in circular cone-beam Computed Tomography(CT).First,projected areas of steel balls were segmented from the background by using the Otsu’s method,and the mass centers of balls were calculated.Then,the elliptic functions for mass centers were fitted by the least-square algorithm,and the rotation angle of detector was determined by Cho’s geometric calibration method for circular scanning.Finally,the rotated mass centers were fitted as two ellipses,and the rest geometric parameters except the tilted angle of detector were calculated by using Noo’s geometric calibration method for circular scanning.Experimental results indicate that the measuring precisions of rotation angle and skew angle for the detector are 0.02 °and 0.01°,respectively,the measuring precisions of source-detector-distance and source-object-distance are 0.05 mm and 0.01 mm,respectively;and the calculating precisions of orthogonal projection coordinates of source are 0.07 mm and 0.15 mm.The proposed method depress the geometric artifacts significantly,and can satisfy the demands of high-precision image reconstruction.
出处 《光学精密工程》 EI CAS CSCD 北大核心 2013年第7期1659-1665,共7页 Optics and Precision Engineering
基金 国家863高技术研究发展计划资助项目(No.2012AA011603)
关键词 锥束CT 半覆盖扫描 几何校正 图像重建 cone-beam CT half-cover scanning geometric calibration image reconstruction
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参考文献14

  • 1NOO F, CLACKDOYLE R, MENNESSIER C, et al.. Analytic method based on identification of el- lipse parameters for scanner calibration in cone- beam tomography [J].Physics in Medicine and Bi- ology, 2000, 45(11): 3489-3508.
  • 2CHO Y, MOSELEY D J, SIEWERDSEN J H, et al.. Accurate technique for complete geometric cal- ibration of cone-beam computed tomography sys- tems[J]. Medical Physics, 2005, 32(4): 968-983.
  • 3WU D F, LI L, ZHANG L, et al.. Geometric cali- bration of cone-beam CT with a flat-panel deteetor[C]. IEEE Nuclear Science Symposium Conference, Va- lencia, Spain: NSS/MIC, 2011: 2952-2955.
  • 4KYRIAKOU Y, LAPP R M, HILLEBRAND L, et al.. Simultaneous misalignment correction for ap- proximate circular cone-beam computed tomography [J]. Physics in Medicine and Biology, 2008, 53 (22) : 6267-6289.
  • 5李保磊,张耀军.X射线CT系统投影旋转中心的测量[J].光学精密工程,2011,19(5):967-971. 被引量:7
  • 6FELDKAMP L, DAVIS L C , KRESS J W. Practi- cal cone-beam algorithm [J]. Journal of the Opti- cal Society America A, 1984, 1(6): 612-619.
  • 7TUY H K. An inversion formula for cone-beam re- construction [J]. SIAM Journal on Applied Math- ematics, 1983, 43(3): 546-552.
  • 8刘丰林,乔桂锋,邹斌.工业CT图像圆精确测量[J].光学精密工程,2009,17(11):2842-2848. 被引量:6
  • 9陶李,王珏,邹永宁,伍立芬,王慧倩.改进的Zernike矩工业CT图像边缘检测[J].中国光学,2012,5(1):48-56. 被引量:14
  • 10邹晓兵 曾理.锥束螺旋CT半覆盖扫描重建.光学精密工程,2010,:434-442.

二级参考文献53

共引文献38

同被引文献61

  • 1邹晓兵 曾理.锥束螺旋CT半覆盖扫描重建.光学精密工程,2010,:434-442.
  • 2FELDKAMP L A, DAVIS L C, KRESS J W. Practical cone-beam algorithm [J]. JOSA A,1984,1(6) :612-619.
  • 3NOO F, CLACKDOYLE R, MENNESSIER C, et al: Analytic method based on identification of el- lipse parameters for scanner calibration in cone-beam tomography[J]. Phys Med Biol, 2000,45 (11) :3489-3508.
  • 4YANG K, KWAN A L, MILLER D F, et al: A geometric calibration method for cone beam CT systems[J]. Med Phys, 2006,33(6) : 1695-1706.
  • 5SMEKAL L V, KACHELRIEI3 M, STEPINA E, et al: Geometric misalignment and calibration in cone-beam tomography [ J ]. Medical Physics, 2004,31(12) :3242.
  • 6CHO Y, MOSELEY D J, SIEWERDSEN J H, et al: Accurate technique for complete geometric cal- ibration of cone-beam computed tomography sys- tems[J]. MedPhys, 2005,32(4) :968-983.
  • 7LI X, ZHANG D, LIU B. A generic geometric cali- bration method for tomographic imaging systems with flat-panel detectors A detailed implementa- tion guide [J]. Medical Physics, 2010, 37 (7): 3844.
  • 8GROSS D, HEIL U, SCHULZE R, et al: Auto calibration of a cone-beam-CT[J]. Medical Phys- ics, 2012,39(10) :5959.
  • 9KINGSTON A, SAKELLARIOU A, VARSLOTT, et al: Reliable automatic alignment of tomo- graphic projection data by passive auto-focus [J]. Medical Physics, 2011,38(9) :4934.
  • 10YUANZHENG M, HUI G, XIAOQUAN Y. On- line geometric calibration of cone-beam computed tomography ,for arbitrary imaging objects [J]. IEEE Transactions on Medical Imaging, 2013,32 (2):278-288.

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