Table 1 Terms used to portray the perfusion by contrast-enhanced ultrasonography
Acronym | Parameter | Notes |
|---|---|---|
TIC | time-intensity curve | A curve to describe the signal intensity of contrast media in a region of interest changes over time when a series of ultrasonograms are analysed by specific software offline |
ROI | region of interest | A circle drawn in the interested region for generating the time-intensity curve. In this study, one ROI took the tumor region as a whole, the other one, "hotspot", was located in the highest enhanced area on contrast-enhanced ultrasonography, which were determined by the two sonography investigators |
ISI | increased signal intensity | The difference between baseline to the maximum increase in signal intensity in a region of interest |
RSI | rate of signal increase | The rate of signal enhancement from baseline to initial peak in a region of interest |
RWO | rate of washout of 50% of contrast material | The rate of signal intensity reduced to 50% of initial peak of contrast material in a region of interest |
MTT | mean transit time | Average persistence of a contrast material in a region of interest |
AUC | area under the curve | Integral calculus of the area under time-intensity curve, which reflects the total perfusion of a region of interest |
BF | blood flow coefficient | BF = AUC/MTT/2 |