Quantitative myocardial perfusion imaging across PET, SPECT, CMR, and CT

Figures

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  Figure 1. Myocardial perfusion imaging across modalities. (A) Compartment model. Illustration of contrast agent (blue dots) distribution in the tissue: vp is intravascular plasma volume; ve is the extravascular extracellular space; F is perfusion flow; PS is permeability-surface exchange rate between vp and ve. Another parameter, the extraction fraction (E) denotes the proportion of contrast agent exchanged to the extravascular extracellular space. (B) PET tracer kinetics. Relationships between MBF and tracer uptake rate K1 (left), and with simplified retention modeling of tracer net uptake (middle). Shaded regions represent variability in reported values. As blood flow increases, the myocardial extraction of 82Rb levels off, resulting 82Rb uptake K1 reaches a plateau. In tracers such as [15O]H2O, [13N]NH3, and [18F]Flurpiridaz, extraction fraction keeps close to 1.0, resulting K1 increases proportionally to MBF. Polar maps (right) illustrate MBF, uptake, and retention along with their relationship to traditional relative MPI in example using [13N]NH3. Limited extraction fraction at higher MBF reduces uptake and retention in high-flow regions. Consequently, contrast between high- and…