TY - GEN
T1 - Real-time MRI for assessment of PET/CT attenuation correction protocols
AU - Hamill, James J.
AU - Kino, A.
AU - Li, D.
AU - Weale, P.
AU - Jerecic, R.
AU - Platsch, G.
AU - Hayden, C.
AU - Burckhardt, D.
AU - Carr, J.
PY - 2008
Y1 - 2008
N2 - A geometrical mismatch between emission and transmission occurs in cardiac PET/CT because of respiratory and cardiac motions. Proposed solutions to this problem include fast CT during free breathing, with or without image alignment, and slow CT. To study this problem, including the variability of human breathing patterns and compliance with instructions, we performed real-time FISP MRI measurements of two freebreathing volunteer subjects. We have developed a method for simulating PET and CT coronal images from these image sequences, and for locating the left cardiac free wall semiautomatically. The PET geometry represents an average over the whole MR examination. The simulated CT geometry represented 28.8 mm axial extent and speeds of 83 mm/sec (fast) and 12 mm/sec (slow), representing a Senation-64 CT scanner running at fast and slow settings. We considered 400 start times for each CT geometry. The free wall was located in each CT image and was compared with the location expected in PET. The error in a given CT scan depends on the geometry, i.e. fast or slow scan, and also on the state of breathing at the time of the scan. A more accurate result can be realized by selecting the best-aligned of two or three fast CT scans. The average errors in fast, slow, best of 2, and best of 3 fast CT scans are respectively 5, 4, 4, and 3 mm. The errors in these scans have 98% likelihood of being less than, respectively, 14, 9, 9, and 7 mm.
AB - A geometrical mismatch between emission and transmission occurs in cardiac PET/CT because of respiratory and cardiac motions. Proposed solutions to this problem include fast CT during free breathing, with or without image alignment, and slow CT. To study this problem, including the variability of human breathing patterns and compliance with instructions, we performed real-time FISP MRI measurements of two freebreathing volunteer subjects. We have developed a method for simulating PET and CT coronal images from these image sequences, and for locating the left cardiac free wall semiautomatically. The PET geometry represents an average over the whole MR examination. The simulated CT geometry represented 28.8 mm axial extent and speeds of 83 mm/sec (fast) and 12 mm/sec (slow), representing a Senation-64 CT scanner running at fast and slow settings. We considered 400 start times for each CT geometry. The free wall was located in each CT image and was compared with the location expected in PET. The error in a given CT scan depends on the geometry, i.e. fast or slow scan, and also on the state of breathing at the time of the scan. A more accurate result can be realized by selecting the best-aligned of two or three fast CT scans. The average errors in fast, slow, best of 2, and best of 3 fast CT scans are respectively 5, 4, 4, and 3 mm. The errors in these scans have 98% likelihood of being less than, respectively, 14, 9, 9, and 7 mm.
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U2 - 10.1109/NSSMIC.2008.4774258
DO - 10.1109/NSSMIC.2008.4774258
M3 - Conference contribution
AN - SCOPUS:67649148331
SN - 9781424427154
T3 - IEEE Nuclear Science Symposium Conference Record
SP - 3761
EP - 3768
BT - 2008 IEEE Nuclear Science Symposium Conference Record, NSS/MIC 2008
T2 - 2008 IEEE Nuclear Science Symposium Conference Record, NSS/MIC 2008
Y2 - 19 October 2008 through 25 October 2008
ER -