BioMed Research International / 2011 / Article / Tab 2 / Review Article
Quantifying Tumor Vascular Heterogeneity with Dynamic Contrast-Enhanced Magnetic Resonance Imaging: A Review Table 2 Model-free parameters often used for DCE-MRI dynamic curve description† .
Parameter Definition Units Alternative names Literature Area-under-the-curve (AUC) Area under the signal intensity or gadolinium dynamic curve a.u·min or mmol·min/L IAUC, AUGC, IAUGC [29 ] Relative signal intensity (RSI)
N/A [30 ] Initial slope Maximum or average slope in the initial enhancement a.u./min Enhancement slope, upslope, enhancement rate [31 ] Washout slope Maximum or average slope in the washout phase a.u./min Downslope, washout rate [32 ] Peak enhancement ratio (PER)
N/A Maximum signal enhancement ratio (
) [33 ]
Time from contrast agent arrive to peak enhancement s Time-to-peak (TTP) Maximum intensity-time ratio (MITR)
[34 ]
† Unlike the pharmacokinetic parameters, the nomenclature for model-free parameters has not been standardized. Notation and abbreviations:
: MR signal intensity at time
;
: precontrast signal intensity;
: maximum signal intensity; a.u.: arbitrary unit.