Purpose: To evaluate whether changes of dynamic contrast-enhanced ultrasound (CEUS)-based liver microcirculation during chronic liver disease are correlated with the extent of impaired liver function, expressed by the indocyanine green (ICG) clearance.
Materials and methods: 19 patients underwent CEUS examinations with previous or consecutive ICG clearance test. The ICG plasma disappearance rate (ICG-PDR) was determined using the noninvasive pulse-densitometric LiMON system. Quantification of peak enhancement (PE), rise time (RT) and the wash-in rate (WiR) was performed in the liver parenchyma (ROIliver) as well as in the portal vein (ROIportal vein) using a novel quantification software (VueBoxTM). To compare quantification parameters, patients were classified in patients representing a healthy population (ICG-PDR >16, n = 8) and those representing patients with liver disease (ICG-PDR ≤16, n = 11).
Results: ROIportal vein showed significant differences comparing healthy patients and patients with liver disease for all perfusion parameters: PE and WiR were significantly higher in patients without liver disease (p = 0.048; p = 0.039). RT was significantly lower in healthy population (p = 0.039). Comparing perfusion parameters for ROIliver, PE was significantly higher in patients without liver disease (p = 0.039). There was no significant difference for RT (p = 0.804) and WiR (p = 0.058), respectively.
Conclusion: Within the framework of this study CEUS derived estimation of microcirculation did not prove to be a reliable estimator of liver function. RT, PE and WiR measured in the portal vein were significant perfusion factors in predicting liver function.
Keywords: CEUS; Chronic liver disease; ICG-test; liver function; microcirculation.