Evaluation of 4D-NCAT Phantom to simulate Dynamic Behavior of Radiopharmaceutical in Myocardium

 Introduction: Studying the heart tissue kinetics can lead to expedient diagnostic technique to study the spatial and temporal cardiac activity simultaneously. Simulations of this process requires phantom, which applies dynamic activity changes gradually to the regions of interest. The objective of this study was to validate the efficiency of 4D-NCAT phantom data in the dynamic activity changes in course of the time.  Materials and Methods: The accuracy of constant, ascending and descending steep Time activity Curves (TACs) in blood and myocardial tissue were measured after i99m-Tc teboroxime injection. Also, the accuracy of phantom output data was measured in different resolution.  Results: Our study showed that the response of the dynamic 4D NCAT phantom for constant curves had just some slight errors. The average relative differences between input and output data for steeper TACs were noteworthy in both ascending and descending mode. The results showed that by increasing the temporal data sampling, the average difference between input and outputs were decreased. Overall, only 0.6% of the assessed samples depicted relative errors larger than 0.1%. Conclusion: The primary studies with available 4D NCAT software, version 2012, revealed some challenges in applying intended activity with TACs, which referred to and were subsequently resolved by Dr. Paul Segars revisions. Overall, the modified 4D NCAT phantom software is able to accurately simulate the organ dynamics.