RT Journal Article
SR Electronic
T1 Estimation of myocardial blood flow using multi-detector CT as compared with 15O-H2O PET: Strategy for reducing radiation dose in myocardial CT study
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 209
OP 209
VO 56
IS supplement 3
A1 Katoh, Chietsugu
A1 Tomiyama, Yuuki
A1 Takeuchi, Keisuke
A1 Manabe, Osamu
A1 Tamaki, Nagara
YR 2015
UL http://jnm.snmjournals.org/content/56/supplement_3/209.abstract
AB 209 Objectives Using 15O-H2O myocardial PET data, we developed a new protocol to estimate myocardial blood flow (MBF) from dynamic multi-detector CT with low dose radiation exposure.Methods Twenty-two subjects underwent both dynamic multi-detector CT and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group),the calculation method for MBF with single compartment model and Renkin-Crone model was established. In the other 10 normal subjects (validation group), MBF estimated by dynamic CT and PET were compared. The dynamic CT data were acquired at every heart beat for 20 seconds with ECG gated scanning. Radiation exposure dose for each scan was 0.3mSv. About 30 beats data were acquired for each study, exposure dose was about 9mSv. To develop a low dose exposure CT study protocol for estimating MBF, MBF were recalculated using skipped CT data for 1,2,3 and 4 beats interval. Relationship was evaluated between correct MBF from PET and skipped CT data, allowed beat interval to estimate MBF with CT was assessed.Results In the pilot group data at rest and during stress (n=24), significantly strong correlation was yielded between MBF from no-skipped CT data and PET (r=0.950, P<0.01). In the validation group data at rest and during stress (n=20), correlation coefficients between MBF from no-skipped CT data and skipped CT data for 1,2,3 and 4 beats interval were 0.995, 0.990, 0.983 and 0.953, respectively. The differences in these correlation coefficients were compared using Fisher's z-transformation, MBF from 4 beats interval CT data yielded significantly low coefficient (p<0.01), We found that at least 3 beats interval data is needed for appropriate estimation of MBF by ECG gated CT.Conclusions Using 15O-H2O myocardial PET data, we established a method for measuring MBF with ECG-gated dynamic multi-detector CT for 3 beats interval. It will reduce the radiation exposure to 1/4 compared with no-skipped CT study.