Performance standardization of dynamic range for accurate quantification of myocardial blood flow using 3D PET-CT

Objectives 3D-mode imaging is the standard for new commercial PET-CT systems. Dynamic imaging for quantification of myocardial blood flow (MBF) with short-lived tracers such as Rb-82 requires accuracy to be maintained over a wide range of activities. We propose new performance standards to characterize the dynamic range of six 3D PET-CT systems.

Methods Scans were performed with 1000-1500 MBq of Rb-82 injected into the myocardial wall of a cardiac insert in an anthropomorphic torso phantom simulating a 70 kg patient. Dynamic images (32 x 15s) were reconstructed using vendor-supplied iterative algorithms with all corrections enabled. Myocardial time-activity curves (TAC) were extracted using FlowQuant© (UOHI). Dynamic range was defined as the maximum activity in the myocardial wall with < 10% bias in accuracy. Scatter correction residual bias was estimated as the maximum blood cavity:myocardium ratio.

Results The maximum activity, injected dose/kg, dead-time correction factor (DTF) and residual scatter bias are shown in Table 1 for accurate quantitative cardiac MBF imaging on 6 scanners.

Conclusions Quantitative 3D cardiac imaging appears to be feasible using the 6 investigated PET-CT scanners within the dynamic range of activities reported. Clinical validation studies should confirm accuracy using the maximum dose/weight recommendations.

Research Support CIHR grant MIS100935.