Radiomics of Multi-modality Ultrasound in Rabbit VX2 Liver Tumors: Differentiating Residual Tumors from Hyperemic Rim After Ablation

Purpose To investigate the value of quantitative features extracted from multi-modality ultrasound, composed of B-mode ultrasound (BUS), strain elastography (SE), and contrast-enhanced ultrasound (CEUS), in the early differentiation of residual tumors from hyperemic rim after ablation for rabbit VX2 liver tumors. Methods The study included sixteen rabbits undergoing ablation for normal liver tissue or VX2 liver tumors. BUS, SE, and CEUS examinations of rabbit livers were performed on day 3 and day 7 after ablation. A total of 108 radiomics features were extracted. Spearman rank correlation, the t-test, Kruskal-Wallis test (KW-test), and the least absolute shrinkage and selection operator (LASSO) method were applied to analyze data. The support vector machine (SVM) and logistic regression (LR) classifiers were used to classify hyperemic rim and residual tumors under the leave-one-out cross-validation. Model performance was validated by the area under the receiver operating characteristic curve (AUC). Results All ultrasound modalities had features that significantly differed between hyperemic rim and residual tumors, such as the maximal value of BUS, the entropy of brightness of SE, and the skewness value of CEUS (all p < 0.05). For the differentiation between hyperemic rim and residual tumors after ablation, the AUC of multi-modality ultrasound was 93.3% on day 3 and 82.1% on day 7. Conclusion The multi-modality ultrasound radiomics is helpful for the early differentiation between hyperemic rim and residual tumors around the ablation area in a rabbit model, which might improve future ablation for liver tumors.