TY - GEN
T1 - Image evaluation for CZT Compton PET using backprojection and MLEM method
AU - Yoon, Changyeon
AU - Lee, Wonho
PY - 2011
Y1 - 2011
N2 - This study presents the image evaluation for CZT Compton PET using simple backprojection and an MLEM (Maximum Likelihood Expectation Maximization) method. Compton PET can use not only the photoelectric effect but also the Compton scattering effect for image reconstruction, and hence the detection efficiency should be inherently higher than that of conventional PET. By using a pixelized CZT detector, the detected position and deposited energy of the gamma ray were found precisely. With the position and energy information, the interaction sequence, which was one of the main factors to consider in the reconstruction of the source image, was identified correctly. The reconstruction algorithms were simple backprojection and MLEM, and three methods were used to evaluate the CZT Compton PET compared with conventional PET which uses the photoelectric effect only. The FWHMs (Full Widths at Half Maximum) and the maximum counts of images reconstructed by simple backprojection were calculated for comparison. Using an MLEM method, the FWHM and the relative standard deviation of the counts in the range of half of the FWHM around the maximum pixel were calculated at each iteration to evaluate the modalities quantitatively. For a 3D source phantom, simple backprojection and the MLEM method were applied to each modality and the reconstructed images were compared with each other by visual inspection.
AB - This study presents the image evaluation for CZT Compton PET using simple backprojection and an MLEM (Maximum Likelihood Expectation Maximization) method. Compton PET can use not only the photoelectric effect but also the Compton scattering effect for image reconstruction, and hence the detection efficiency should be inherently higher than that of conventional PET. By using a pixelized CZT detector, the detected position and deposited energy of the gamma ray were found precisely. With the position and energy information, the interaction sequence, which was one of the main factors to consider in the reconstruction of the source image, was identified correctly. The reconstruction algorithms were simple backprojection and MLEM, and three methods were used to evaluate the CZT Compton PET compared with conventional PET which uses the photoelectric effect only. The FWHMs (Full Widths at Half Maximum) and the maximum counts of images reconstructed by simple backprojection were calculated for comparison. Using an MLEM method, the FWHM and the relative standard deviation of the counts in the range of half of the FWHM around the maximum pixel were calculated at each iteration to evaluate the modalities quantitatively. For a 3D source phantom, simple backprojection and the MLEM method were applied to each modality and the reconstructed images were compared with each other by visual inspection.
UR - http://www.scopus.com/inward/record.url?scp=84863387270&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84863387270&partnerID=8YFLogxK
U2 - 10.1109/NSSMIC.2011.6154620
DO - 10.1109/NSSMIC.2011.6154620
M3 - Conference contribution
AN - SCOPUS:84863387270
SN - 9781467301183
T3 - IEEE Nuclear Science Symposium Conference Record
SP - 1377
EP - 1379
BT - 2011 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2011
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2011 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2011
Y2 - 23 October 2011 through 29 October 2011
ER -