Dynamic Contrast Ultrasound Diagnostics (CEUS) of Liver Lesions and Post-treatment Control with A New High-resolution Examination Technique (HiFR) and Perfusion.

Background and aims: To evaluate, if high frame rate (HiFR) contrast-enhanced ultrasound (CEUS) and external perfusion analysis (VueBox®)can give answers on liver tumour diagnostics.

Methods: A multifrequency probe (C1-6 /Resona R9) and 1-2.4 ml ultrasound contrast medium were used for CEUS up to 5-6 min. Independent analysis of DICOM-CINE files was performed, correlated to follow-up, computed tomography, magnetic resonance imaging, or histopathology.

Results: In 110 patients the difference between marginal peak enhancement (PE) of malignant and benign leasions was significant. In the peripheral area, the AUCs were lower in malignant lesions (144.8±139.3) than in benign lesions (123.6±119.8). The mean transit time (mTT) was shorter in malignant lesions in the center. In the liver parenchyma, however, the mTT was significantly longer in malignant lesions (141.6±107.9s) than in benign lesions (128.8±138.6 s). The rise time (RT) was significantly shorter central (66.5±30.9s) and peripheral (72.8±35.1s) in malignant lesions than in benign lesions (114.33±159.58s). The wash in rate (WiR) in benign lesions was 848.3±2,563.7 rU in the center. Wash-out rate (WoR) in the center, peripheral and in the liver parenchyma showed a significantly lower wash-out in the malignant lesions.

Conclusions: HiFR CEUS with perfusion analysis enables the assessment of focal, diffuse and post-interventional liver changes.