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

TL;DR

This study evaluates kinetic models and scan durations for dynamic 18F-FDG PET imaging in the human heart, demonstrating optimal protocols for quantifying myocardial glucose transport with implications for multiparametric cardiac imaging.

Contribution

It identifies appropriate kinetic models and scan durations for efficient myocardial glucose transport quantification in clinical PET imaging.

Findings

Reversible two-tissue model needed for 1-hour scans.

Irreversible two-tissue model optimal for 10-15 minute scans.

Early 10-15 minute scans with irreversible modeling are comparable to full scans.

Abstract

Cardiac 18F-FDG 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 paper 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 model was needed for a one-hour dynamic scan. The irreversible two-tissue model was optimal for a scan duration of around 10-15 minutes. If the scan duration was shortened to 2-3 minutes, 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 minutes and irreversible kinetic modeling was comparable to the full one-hour 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.