Study of Repeatability of a Novel PET Flow Phantom

Dynamic Positron Emission Tomography (PET) is a valuable method in Myocardial Perfusion Imaging (MPI) allowing quantification of blood flow in the myocardial tissue. A reference test object simulating myocardial blood flow is needed. A newly developed PET phantom enables flow quantification with a known reference. However, the repetability of the flow phantom needs to be confirmed. The aim of this study was to confirm that no significant variability exists between image-derived or reference flow between subsequent measurements. Finally, we confirmed repeatability of the flow values derived by kinetic modelling from PET images of the phantom. Five repeated measurements with fixed acquisition and reconstruction protocol were performed. PET images were analysed with a software provided by the phantom vendor to derive the time-activity curves for modelling of flow values. The image-derived flow rates varied with SD of 0.89 mL/min and 0.86 mL/min between subsequent measurements. Error between image-derived and reference flow was less than 5.5 % on average within all subsequent repeats. Fluctuations between the subsequent measurements are considered to arise from the dose administration and water flow inside the phantom. In conclusion, the newly developed PET flow phantom shows high repeatability and is a reliable platform for quality control and validation studies in MPI in PET.