Table 2.
Summary of parameter terms used in the dual-input extended Tofts model and 2-compartment exchange model
| Symbol | Definition | Unit |
| Ctiss(t) | Concentration of tracer in the tissue | mmol/L |
| CA(t) | Concentration of tracer in whole blood in a major feeding artery | mmol/L |
| Cv(t) | Concentration of tracer in the portal vein | mmol/L |
| Fa | Arterial fraction of the tissue perfusion | % |
| HLV | Hematocrit in major (large) vessels | none |
| HPI | Hepatic perfusion index | none |
| Fp | Flow rate of the blood plasma through the intravascular plasma space | mL/mL per minute |
| vp | Ratio of blood plasma volume to tissue volume | % |
| ve | Ratio of EES volume to tissue volume | % |
| kep | Efflux rate constant | min-1 |
| Ktrans | Transfer constant | min-1 |
| PS | Endothelial permeability surface area product | mL/mL per minute |
| ⊗ | Convolution operator | None |
EES: Extravascular extracellular space.