Related Experiment Video
Updated: May 22, 2026
High-Resolution Cardiac Positron Emission Tomography/Computed Tomography for Small Animals
Published on: December 16, 2022
Feasibility of myocardial perfusion imaging with half the radiation dose using ordered-subset expectation
Nili Zafrir1, Alejandro Solodky, Avi Ben-Shlomo
1Nuclear Cardiology Unit, Department of Cardiology, Rabin Medical Center, Beilinson Campus, 49100 Petach Tikva, Israel. zafrirmd@isdn.net.il
Objective:
This study sought to assess the feasibility of performing myocardial perfusion imaging (MPI) with half the technetium activity using ordered-subset expectation maximization with resolution recovery (OSEM-RR), an iterative reconstruction software developed to improve count statistics and acquisition time.
Methods:
Two hundred eighteen patients referred for MPI were randomly allocated to undergo stress-rest or rest-stress protocols with standard full-dose (FD) injections of technetium (Tc)-99m sestamibi or half-dose (HD) injections and OSEM-RR processing. Dose activities were adjusted individually by weight. The groups were compared for image quality and clinical results.
Results:
The groups were similar for mean patient age, weight, and body mass index, sex distribution, pre-test probability of CAD and CAD prevalence. Mean Tc-99m activities for the low-dose and high-dose stages were as follows: FD group: 429 ± 85 MBq and 1132 ± 200 MBq; HD group: 263 ± 129 MBq and 629 ± 85 MBq (P < .0001 for both). Mean effective dose per study was 13.6 ± 1.4 mSv in the FD group and 7.7 ± 1.0 mSv in the HD group (P < .001). Over all image quality was good-to-excellent in 98% and 95% of the groups, respectively. However, when we analyzed the low-dose stage separately, image quality was slightly worse in the HD than the FD, though still within the good-to excellent range.
Conclusions:
MPI with nearly half the radiation dose is feasible with good image quality.
