During the median follow-up period of 23 months (range 3–90 months), 93.6 % (102/109) lesions showed completed ablation (Fig. 31.3). Six of seven recurred lesions were found by both CEUS and CT/MRI (6/109, 5.5 %). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of recurred tumor detection by CEUS were 85.7, 99.0, 98.2, 85.7, and 99.0 %, respectively. Our results indicate that CEUS may be an effective alternative to CT/MRI in the follow-up of RCC after percutaneous MWA, which is similar to the results after RFA reported by Maria Franca Meloni in 2008 [17].

Meanwhile several studies reported that CEUS played a promising role in evaluating the short-term and long-term therapeutic effects of RCC following different ablations. As shown in Tables 31.1 and 31.2, CEUS is an effective method in assessing the therapeutic effect during the follow-up of RCC followed with RFA, MWA, and cryoablation [3, 4, 17, 23, 24]. Just as conventional US, CEUS is subject to unclear lesion display for abdominal gas shielding or relative operator dependence of US. Sometimes it could be avoided by changing the posture of patient and cleaning the bowel. Otherwise, this situation may affect the assessment of the therapeutic efficiency after ablation.