QUANTITATIVE ROTATING MULTI-SEGMENT SLANT-HOLE SPECT MAMMOGRAPHY WITH ATTENUATION AND COLLIMATOR-DETECTOR RESPONSE COMPENSATION
Jingyan Xu, Ph.D. 1, Benjamin M.W. Tsui, Ph.D 1, Chi Liu, B.S. 1 and Eric C. Frey, Ph.D. 1 ; 1 Radiology, Johns Hopkins University, Baltimore, MD, United States.
The objective of this work was to improve the quality and quantitative accuracy of rotating multi-segment slant-hole (RMSSH) SPECT reconstruction by compensating for both attenuation and collimator-detector response (CDR).
METHODS AND MATERIALS:
Attenuation is modeled using an
attenuation map obtained from a transmission CT scan. The CDR of a slant-hole
collimator is asymmetric and has a different orientation relative to the
patient for each segment and at each collimator rotation stop. All required
CDRs were pre-calculated using an analytical formulation.
Our results show that in RMSSH SPECT, (1) while AC by itself improves quantitative accuracy, it may reduce lesion contrast in breast imaging, and (2) simultaneous AC and CDR compensation provides better quantitative accuracy and improved image quality in terms of resolution enhancement with minimum noise increase. Observer studies are on-going to further evaluate the clinical applicability of RMSSH SPECT reconstruction with compensation.
We conclude that improved image quality and quantitative accuracy can be obtained with attenuation and CDR compensation in RMSSH SPECT.