Super-Resolution Contrast-Enhanced Ultrasound Examination Down to the Microvasculature Enables Quantitative Analysis of Liver Lesions: First Results

This article investigates the first use of dynamic microvascularization of liver lesions in clinical evaluation using real-time super-resolution contrast-enhanced ultrasound (SR CEUS). A retrospective analysis of SR CEUS examinations of liver lesions was performed. All examinations were conducted using an SC7-1U convex probe after the bolus injection of the ultrasound contrast agent. Digital cine loops were stored for independent evaluation. The evaluation was performed with respect to parallel measuring lines (the diameter corresponded to the capillary density) in the area of the reference lesion, liver tissue, and liver capsule using statistical analysis. In total, 65 patients (female <i>n</i> = 28; male <i>n</i> = 37; average age 57.8 ± 17.2 years) were evaluated. The examined liver lesions were mostly benign masses (<i>n</i> = 46). Mild liver fibrosis (stage F1) was present in most cases (<i>n</i> = 35). The lesions examined were located at an average tissue depth of 6.07 ± 2.47 cm. The highest number of lesion measurements was observed in the malignant lesion group. Significant differences in the measurements were found when comparing benign lesions with the capillary region (<i>p</i> < 0.001) and normal liver tissue (<i>p</i> < 0.01). The use of SR CEUS opens up new possibilities for the quantification of neovascularization, assessment of microvascular changes, and evaluation of the follow-up of intrahepatic interventions.