Nuclear Medicine and Molecular Imaging

The Korean Society of Nuclear Medicine (대한핵의학회)
권호 표지

Compensation Methods for Non-uniform and Incomplete Data Sampling in High Resolution PET with Multiple Scintillation Crystal Layers

다중 섬광결정을 이용한 고해상도 PET의 불균일/불완전 데이터 보정기법 연구

  • Lee, Jae-Sung (Departments of Nuclear Medicine, College of Medicine, Seoul National University) ;
  • Kim, Soo-Mee (Departments of Nuclear Medicine, College of Medicine, Seoul National University) ;
  • Lee, Kwon-Song (Departments of Biomedical Engineering, College of Medicine, Seoul National University) ;
  • Sim, Kwang-Souk (Department of Physics, Korea University) ;
  • Rhe, June-Tak (Department of Physics, Konkuk University) ;
  • Park, Kwang-Suk (Departments of Biomedical Engineering, College of Medicine, Seoul National University) ;
  • Lee, Dong-Soo (Departments of Nuclear Medicine, College of Medicine, Seoul National University) ;
  • Hong, Seong-Jong (Departments of Nuclear Medicine, College of Medicine, Seoul National University)
  • 이재성 (서울대학교 의과대학 핵의학교실) ;
  • 김수미 (서울대학교 의과대학 핵의학교실) ;
  • 이건송 (서울대학교 의과대학 의공학교실) ;
  • 심광숙 (고려대학교 물리학과) ;
  • 이준택 (건국대학교 물리학과) ;
  • 박광석 (서울대학교 의과대학 의공학교실) ;
  • 이동수 (서울대학교 의과대학 핵의학교실) ;
  • 홍성종 (서울대학교 의과대학 핵의학교실)
  • Published : 2008.02.29
Download PDF
⟨ Previous Next ⟩

Abstract

Purpose: To establish the methods for sinogram formation and correction in order to appropriately apply the filtered backprojection (FBP) reconstruction algorithm to the data acquired using PET scanner with multiple scintillation crystal layers. Materials and Methods: Formation for raw PET data storage and conversion methods from listmode data to histogram and sinogram were optimized. To solve the various problems occurred while the raw histogram was converted into sinogram, optimal sampling strategy and sampling efficiency correction method were investigated. Gap compensation methods that is unique in this system were also investigated. All the sinogram data were reconstructed using 20 filtered backprojection algorithm and compared to estimate the improvements by the correction algorithms. Results: Optimal radial sampling interval and number of angular samples in terms of the sampling theorem and sampling efficiency correction algorithm were pitch/2 and 120, respectively. By applying the sampling efficiency correction and gap compensation, artifacts and background noise on the reconstructed image could be reduced. Conclusion: Conversion method from the histogram to sinogram was investigated for the FBP reconstruction of data acquired using multiple scintillation crystal layers. This method will be useful for the fast 20 reconstruction of multiple crystal layer PET data.

목적: 다중섬광결정 PET으로 얻은 데이터에 대한 여과후역투사 영상재구성 적용을 위한 사이노그램 저장과 보정 방법을 확립하고자 한다. 대상 및 방법: 검출된 PET 데이터에 대한 저장기법에 대한 연구를 수행하여 효율적 영상재구성을 위한 사이노그램 방식을 확립하였다. 히스토그램에서 사이노그램으로 데이터를 변환할 때 생기는 제반 문제들을 해결하기 위하여 데이터 표본의 최적화와 표본 불균일성 보정기법에 관한 연구를 수행하였으며, PMT간 틈새 보정을 위 한 연구를 수행하였다. 모든 데이터는 2차원 여과후역투사 알고리즘을 이용하여 재구성하였으며 보정에 따른 영상질의 향상을 평가하였다. 결과: 표본이론에 의해서 추정된 최소 표본수와 표본 불균일성 보정기법의 적용을 위한 수월성 등을 고려할 때 방사방향 표본간격이 pitch/2, 각 표본수가 120개 정도가 적절하였으며, 불균일성 보정과 틈새보정을 적용함으로서 영상왜곡과 배경잡음을 줄일 수 있었다. 결론: 다층섬광결정 PET의 FBP 영상재구성을 위하여 히스토그램 데이터를 사이노그램으로 변환하는 기법에 대한 연구가 이루어졌으며 이를 통한 고속의 2D 영상재구성이 가능할 것으로 보인다.

Keywords

References

  1. Pomper MG, Lee JS. Small animal imaging in drug development. Curr Pharm Des. 2005;11:3247-72 https://doi.org/10.2174/138161205774424681
  2. Phelps ME. Nuclear medicine, molecular imaging, and molecular medicine. J Nucl Med. 2002;43:13N-4N
  3. Pomper MG. Can small animal imaging accelerate drug development? J Cell Biochem Suppl. 2002;39:211-20
  4. Gambhir SS. Molecular imaging of cancer with positron emission tomography. Nat Rev Cancer. 2002;2:683-93 https://doi.org/10.1038/nrc882
  5. Moses WW. Trends in PET imaging. Nucl Instrum Meth A 2001;471:209-14 https://doi.org/10.1016/S0168-9002(01)00969-X
  6. Green MV, Seidel J, Vaquero JJ, Jagoda E, Lee I, Eckelman WC. High resolution PET, SPECT and projection imaging in small animals. Comput Med Imaging Graph. 2001;25:79-86 https://doi.org/10.1016/S0895-6111(00)00057-4
  7. Seidel J, Vaquero JJ, Siegel S, Gandler WR, Green MV. Depth identification accuracy of a three layer phoswich PET detector module. IEEE Trans Nucl Sci. 1999;46:485-90 https://doi.org/10.1109/23.775567
  8. Streun M, Brandenburg G, Larue H, Saleh H, Zimmermann E, Ziemons K et al. Pulse shape discrimination of LSO and LuYAP scintillators for depth of interaction detection in PET. IEEE Trans Nucl Sci. 2003;50:344-7 https://doi.org/10.1109/TNS.2003.812449
  9. Zhang N, Thompson CJ. Optimizing position readout circuits in positron emission tomography: front-end electronics. IEEE Trans Nucl Sci. 2003;50:1398-403 https://doi.org/10.1109/TNS.2003.817954
  10. Hong SJ, Lee JS, Sim KS, Kim SM, Moon DH, Hong B, et al. Improving DOI information using 3-layer crystals for small animal PET. Proc IEEE Nucl Sci Symp Med Imag Conf. 2004;4:2434-8
  11. Lee JS, Hong SJ, Kim SM, Sim KS, Hong B, Lee KS, et al. Design, simulation, and reconstruction strategies for small animal PET scanner with 3-layer phoswich crystals and PMT with large effective area ratio. J Nucl Med. 2005;6:491P. Abstract
  12. Defrise M, Kinahan PE, Townsend DW, Michel C, Sibomana M, Newport DF. Exact and approximate rebinning algorithms for 3-D PET data. IEEE Trans Med Imaging. 1997;16:145-58 https://doi.org/10.1109/42.563660
  13. Virador PRG, Moses WW, Huesman RH. Reconstruction in PET cameras with irregular sampling and depth of interaction capability. IEEE Trans Nucl Sci. 1998;45:1225-30 https://doi.org/10.1109/23.682007
  14. Karp JS, Muehllehner G, Lewitt RM. Constrained Fourier space method for compensation of missing data in emission computed tomography. IEEE Trans Med Imaging. 1988;7:21-5 https://doi.org/10.1109/42.3925
  15. Baghaei H, Li H, Uribe J, Wang Y, Wong W-H. Compensation of missing projection data for MDAPET camera. Proc IEEE Nucl Sci Symp Med Imag Conf. 2000;3:17/41-17/45
  16. Michel C, Schmand M, Liu X, Sibomana M, Vollmar S, Knoss C et al. Reconstruction strategies for the HRRT. Proc IEEE Nucl Sci Symp Med Imag Conf. 2000;2:15/207-15/212
  17. Yao R, Seidel J, Johnson CA, Daube-Witherspoon ME, Green MV, Carson RE. Performance characteristics of the 3-D OSEM algorithm in the reconstruction of small animal PET images. Ordered- subsets expectation-maximization. IEEE Trans Med Imaging. 2000;19:798-804 https://doi.org/10.1109/42.876305
  18. Agostinelli S, Allison J, Amako K, Apostolakis J, Araujo H, Arce P et al. Geant4?a simulation toolkit. Nucl Instrum Meth A. 2003;506:250-303 https://doi.org/10.1016/S0168-9002(03)01368-8
  19. Allison J, Amako K, Apostolakis J, Araujo H, Arce Dubois P, Asai M et al. Geant4 developments and applications. IEEE Trans Nucl Sci. 2006;53:270-8 https://doi.org/10.1109/TNS.2006.869826
  20. Peters TM. Algorithms for fast back- and re-projection in computed tomography. IEEE Trans Nucl Sci. 1981;28:3641-7 https://doi.org/10.1109/TNS.1981.4331812
  21. Zhuang W, Gopal SS, Hebert TJ. Numerical evaluation of methods for computing tomographic projections. IEEE Trans Nucl Sci. 1994;41:1660-5 https://doi.org/10.1109/23.322963