Multiparametric Cardiac 18F-FDG PET in Humans: Kinetic Model Selection and Identifiability Analysis

Cardiac
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F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been used in clinics to assess myocardial glucose metabolism. Its ability for imaging myocardial glucose transport, however, has rarely been exploited in clinics. Using the dynamic FDG-PET scans of ten patients with coronary artery disease, we investigate in this article appropriate dynamic scan and kinetic modeling protocols for efficient quantification of myocardial glucose transport. Three kinetic models and the effect of scan duration were evaluated by using statistical fit quality, assessing the impact on kinetic quantification, and analyzing the practical identifiability. The results show that the kinetic model selection depends on the scan duration. The reversible two-tissue (2T) model was needed for a 1-h dynamic scan. The irreversible 2T model was optimal for a scan duration of around 10-15 min. If the scan duration was shortened to 2-3 min, a one-tissue model was the most appropriate. For global quantification of myocardial glucose transport, we demonstrated that an early-dynamic scan with a duration of 10-15 min and irreversible kinetic modeling was comparable to the full 1-h scan with reversible kinetic modeling. Myocardial glucose transport quantification provides an additional physiological parameter on top of the existing assessment of glucose metabolism and has the potential to enable single-tracer multiparametric imaging in the myocardium.