The goal of the project was to study the influence of liver activity during its cranio-caudal respiratory motion on myocardial perfusion imaging (MPI) using, in the supine and prone positions, an anthropomorphic thorax phantom assembly with precisely controlled motions of thoracic organs, consisting of (a) an existing beating and moving during respiration human-sized left ventricle phantom with variable sizes of cardiac defects, (b) an existing human-sized and human-shaped inflatable lungs phantom, (c) a proposed human-shaped and human-shaped moving during respiration liver phantom.
The general objectives of the project were to:
(a) Optimize the diagnostic value for the early detection of mild coronary artery disease under the influence of liver activity during its cranio-caudal respiratory motion.
(b) Disseminate the results to interested health professional societies and decision makers to encourage educational and clinical application.
The phantom assembly, including the proposed innovative liver phantom, can be used for Quality Assurance measurements to validate new protocols and algorithms before implementation as well as the proposed methodology can be used for educational purposes by physicians, medical physicists, technicians and students.
Specific Scientific and Technological Objectives
- Develop a moving liver phantom and implement it within the existing anthropomorphic thorax phantom assembly together with the (i) inflatable lungs, and (ii) beating and moving cardiac phantom with variable sizes of cardiac defects
- Acquire and process MP images at the collaborating Hospitals using the corresponding SPECT modalities and the elaborated phantom assembly in supine and prone positions with various (i) sizes of cardiac defects, (ii) hepatic-to-heart activity ratios, (iii) hepatic-to-heart proximities, and (iv) cardiac-lungs-liver oscillation amplitudes during respiration in the cranio-caudal direction (normal and deep breathing).
- Characterize quantitatively artifacts (inferior) due to (i) various hepatic-to-heart activity ratios, (ii) various hepatic-to-heart proximities, (iii) various cardiac-lungs-liver oscillation amplitudes during respiration and (iv) supine and prone imaging, and investigate the impact of artifacts on defect detection
- Correct SPECT images for the cardiac respiratory motion and compare them quantitatively with the non-corrected images, and investigate the impact of motion correction on defect detection
- Compare supine and prone imaging concerning (i) artifacts, (ii) motion correction and (iii) impact on defect detection