Objectives: The aim of this clinical study was to evaluate the reproducibility of quantitative assessment of altered hepatic hemodynamics with dynamic contrast-enhanced ultrasound.
Methods: Fifteen patients with colorectal liver metastases and 5 volunteers were studied. The hepatic artery proper and the portal vein were imaged simultaneously with dynamic contrast-enhanced ultrasound. The examination was repeated with 2 different contrast bolus volumes (1.2 and 2.4 mL), and time-intensity curves were formed from dynamic contrast-enhanced ultrasound image loops. The rise time, peak intensity, and wash-in slope were derived from hepatic artery and portal vein time-intensity curves. Inter-reader, intra-reader, and inter-scan agreement was assessed by 2 independent readers. Quantitative (intraclass correlation coefficients and coefficients of variation [CVs]) and qualitative (Landis and Koch classification) analyses were performed.
Results: Intra-reader and inter-reader agreement was "almost perfect" for the hepatic artery (CV, 10%-15% and 8%-9%, respectively), portal vein (CV, 5%-8% and 6%-12%), and hepatic artery/portal vein ratio (CV, 8%-14% and 10%-15%) measurements of 3 all studied parameters. In contrast, inter-scan agreement was only "slight" to "moderate" (CV, 25%-27%) and "fair" to "moderate" (CV, 19%-24%) for rise time and peak intensity measurements in the hepatic artery and portal vein, respectively.
Conclusions: Quantitative assessment of altered hepatic hemodynamics with dynamic contrast-enhanced ultrasound is reproducible provided that measurements in the hepatic artery are normalized by those in the portal vein.