TY - GEN
T1 - Reconstruction of object-specific attenuation map for quantitative SPECT
AU - Liang, Zhengrong
AU - Ye, Jinghan
PY - 1994
Y1 - 1994
N2 - A method to improve the reconstruction of object-specific attenuation maps for accurate quantification of single-photon emission computed tomography (SPECT) was studied. This method aims to (1) utilize the a priori known attenuation coefficients and (2) compensate for the fan-beam truncation of transmission scans in reconstructing the attenuation map. An external radioactive line source was simulated to generate the fan-beam transmission data through a thorax phantom using a single detector of three-headed SPECT configuration. More than half of the 120 projections distributed evenly over 360 degrees were truncated. The thorax phantom had a size of 1282 array. Emission data was computer synthesized, following the transmission simulation, using two parallel-beam collimated detectors of the SPECT configuration. The simulated emission data was attenuated by the thorax phantom. The transmission data was reconstructed by an iterative maximum a posteriori probability algorithm which simultaneously segments the reconstructed attenuation map with the a priori known attenuation coefficients of bone, lung, soft tissues, and air. The truncation was compensated in the forward projection by estimating the truncated data. The continuity of the estimated data to the simulated data was considered in the backprojection. The truncation-compensated and segmented attenuation map was used to reconstruct the emission data. Significant improvement (> 5%) in quantification of SPECT was achieved, as compared to the reconstruction using the truncated attenuation map.
AB - A method to improve the reconstruction of object-specific attenuation maps for accurate quantification of single-photon emission computed tomography (SPECT) was studied. This method aims to (1) utilize the a priori known attenuation coefficients and (2) compensate for the fan-beam truncation of transmission scans in reconstructing the attenuation map. An external radioactive line source was simulated to generate the fan-beam transmission data through a thorax phantom using a single detector of three-headed SPECT configuration. More than half of the 120 projections distributed evenly over 360 degrees were truncated. The thorax phantom had a size of 1282 array. Emission data was computer synthesized, following the transmission simulation, using two parallel-beam collimated detectors of the SPECT configuration. The simulated emission data was attenuated by the thorax phantom. The transmission data was reconstructed by an iterative maximum a posteriori probability algorithm which simultaneously segments the reconstructed attenuation map with the a priori known attenuation coefficients of bone, lung, soft tissues, and air. The truncation was compensated in the forward projection by estimating the truncated data. The continuity of the estimated data to the simulated data was considered in the backprojection. The truncation-compensated and segmented attenuation map was used to reconstruct the emission data. Significant improvement (> 5%) in quantification of SPECT was achieved, as compared to the reconstruction using the truncated attenuation map.
UR - https://www.scopus.com/pages/publications/0028185007
M3 - Conference contribution
SN - 0780314875
T3 - IEEE Nuclear Science Symposium & Medical Imaging Conference
SP - 1231
EP - 1235
BT - IEEE Nuclear Science Symposium & Medical Imaging Conference
PB - Publ by IEEE
T2 - Proceedings of the 1993 IEEE Nuclear Science Symposium & Medical Imaging Conference
Y2 - 30 October 1993 through 6 November 1993
ER -