Abstract: ［Abstract］Objective〖HTSS〗To explore the applied value of contrast-enhanced ultrasound in evaluating the therapeutic effect during and after microwave ablation for breast nodules.
〖WTHZ〗Methods〖HTSS〗The 43 breast nodules of 30 patients admitted in our hospital were underwent Ultrasound-guided microwave ablation treatment. Before and after microwave ablation operation, two-dimensional ultrasound and contrast-enhanced ultrasound were used to measured the location, number and volume of nodules, observed the distribution and intensity of blood flow in nodules and determined ablation range. Intravenous contrast-enhanced ultrasound detection was carried out immediately after microwave ablation to observe the enhancement state of contrast agent in nodules. The nodules were divided into 3 groups: 1.5-3.5 cm3, ＞3.5-5 cm3 and more than 5 cm3 according to the enhanced volume, to calculate the ablation rate of lesions of each group and evaluate the ablation effect. Supplementary treatment for residual lesions which were incomplete ablation was carried out. The patients were followed up by two-dimensional ultrasound and contrast-enhanced ultrasound after 1, 6 and 12 months of ablation, observed whether there were contrast agent perfusion in nodules and measured the volume and volume reduction rate of nodules. The evaluation of curative effect was also carried out.
〖WTHZ〗Results〖HTSS〗Two-dimensional ultrasound and contrast-enhanced ultrasound both detected blood flow signals in all 43 breast nodules. 15 minutes after microwave ablation, the ablation rates of lesions with enhanced volume of 1.5-3.5 cm3, ＞3.5-5 cm3 and more than 5 cm3 were 97.45%, 89.99% and 67.05% respectively，there was significant statistical difference（P＜0.01）. Contrast-enhanced ultrasound showed there were 8 residual tissue which had a small amount of irregular contrast medium perfusion at the edge of nodules. The successful rate of primary ablation was 81.4%. Supplementary ablation treatment for residual incomplete ablation areas was carried out. There was significant statistical difference among the volume of breast nodules  before and after 1, 6 and 12 months of microwave ablation operation(P＜0.01).  The volume reduction rates were 44.1%, 58.5% and 72.3% respectively, there was significant statistical difference（P＜0.01）.  There were significant differences in clinical efficacy and total effective rate(72.09%, 93.02%,100%) after 1, 6 and 12 months of microwave ablation operation(P＜0.01).
〖WTHZ〗Conclusion〖HTSS〗Contrast-enhanced ultrasound can more accurately determine the location and blood flow distribution of the lesion before microwave ablation and accurately evaluate the ablation effect after ablation operation, so timely supplementary treatment can be provided for incomplete ablation areas. Postoperative follow-up can timely and accurately detect whether residual lesions reappeared again and achieve the complete ablation of breast nodules.

Key words: breast neoplasms, ultrasonography, ablation techniques