Percutaneous Treatment of Malignant Liver Lesions: Evaluation of Success Using Contrast-Enhanced Ultrasound (CEUS) and Perfusion Software

Aim Using new perfusion software for evaluation of the success of percutaneous treatments of malignant liver tumors with CEUS. Materials and Methods Retrospective analysis of 88 patients (74 male, 14 female; 30 - 84 years) with 165 malignant liver lesions. The lesions were 57 metastases and 108 HCCs. The success of interventional treatment (IRE n = 47; RFA n = 38; MWA n = 44; TACE n = 36) was evaluated by CEUS and perfusion software (VueBox (R)). CEUS was performed after injection of 1 - 2.4ml of sulfur hexafluoride microbubbles (SonoVue (R)) using a 1-5MHz convex probe. DICOM loops up to 1 min. in the ablation area were stored digitally in the PACS. Regions of interest (ROI) were manually placed in the center, the margins of the lesions as well as in the surrounding tissue. Using VueBox (R) peak, time to peak (TTP), mean transit time (mTT), rise time (RT), the wash-in and wash-out rate were calculated for the regions, in order to evaluate the success of the percutaneous treatment after the ablation in comparison to the ceCT/ceMRI up to 6 months after the treatment. Results There were significant differences in all cases between the center compared to the margins for the main perfusion parameters (peak, mTT, RT) (p < 0.001). Peak, wash-in and wash-out ratios were further analyzed with the type of lesion and the method of ablation. All parameters were significantly different between lesions treated successfully vs. lesions with recurrence. Conclusion A combination of CEUS with perfusion imaging enables critical assessment of successful treatment after percutaneous interventional procedures for a malignant liver lesion.