OBJECTIVE: To investigate the value of ultrasonography before and after radiofrequency ablation treatment for hepatocellular carcinoma, to quantify and analyze it using time-intensity curve (TIC) to improve the efficacy of radiofrequency ablation treatment, and to compare the therapeutic effect of ultrasonography performed before radiofrequency ablation treatment with that without ultrasonography. Materials and methods: 1. 61 patients (78 lesions) with primary hepatocellular carcinoma hospitalized from October 2010 to November 2011, who met the enrollment criteria for percutaneous radiofrequency ablation and received ultrasound-guided radiofrequency ablation: (1) the number of lesions did not exceed 4; (2) the maximum diameter of lesions did not exceed 8 cm; (3) the prothrombin activity was greater than 50% and the platelet count greater than 50,000/μl; (4) no tumor thrombosis in the main branch of portal vein and no extrahepatic metastasis. The study subjects were divided into two groups: (1) CEUS (contrast-enhanced ultrasonography) group: 30 patients (38 lesions) underwent CEUS before RFA (radiofrequency ablation treatment); (2) control group: 31 patients (40 lesions) Only conventional ultrasound examination was performed before RFA. The clinical data of the two groups did not differ significantly.2. Contrast agent and instrumentationContrast agent was SonoVue. ultrasound diagnostic instrument was IU22 from PHILIPS. radiofrequency ablation treatment instrument was cold circulation ultra-energy radiofrequency tumor system and cold circulation radiofrequency electrode from Valleylab, USA.3. Study methodsFirst, both groups were firstly examined with conventional 2D ultrasound and color In the CEUS group, after the possible location of the lesion was determined by conventional ultrasound, the liver was switched to real-time gray-scale harmonic contrast mode, and the perfusion patterns of the arterial, portal and delayed phases of the lesion were observed continuously in real-time after rapid injection of 2.4 ml of contrast agent (SonoVue). When the observation was unsatisfactory after the first injection of contrast agent or the suspicious area needed to be observed, a second imaging was performed. The RF treatment strategy was designed in parallel with RFA treatment according to the imaging results. about 20-40 minutes after the end of RFA, the imaging could be repeated again to repeat the ablation of incomplete lesions. In the control group, the indications were determined with reference to the information obtained from conventional 2D ultrasound or CT parallel to RFA treatment. After treatment, regular follow-up was performed by conventional ultrasound, enhanced CT and/or ultrasonography, at least 3 months, and enhanced CT was used as a criterion to judge the degree of tumor ablation. 4. CEUS quantitative analysis method CEUS examination was performed on the CEUS group before and after RFA treatment. The tumor tissue without necrosis and the same depth of tumor with equal area of liver parenchyma were selected as the area of interest, and time-intensity curves were made to obtain quantitative analysis results, and the corresponding analysis data were recorded. The quantitative analysis indexes included initialtime (IT), initial intensity (II), time topeak (TTP), peak intensity (PI), enhancement rate (V1) and fading rate (V2). Results: 1. Tumors with unclear borders were shown by conventional ultrasound, and the size measurements of the lesions in the arterial phase increased and the morphology became more irregular and clearer after ultrasonography, and the difference was statistically significant (P < 0.05). 2. Ultrasonography was performed before RFA treatment and TIC was applied to 10 of the tumors for quantitative analysis, and compared with liver parenchyma. The IT and TTP of the liver tumor were significantly smaller than those of the liver parenchyma, and the difference was statistically significant (P < 0.05), while V1 and V2 of the tumor sites were larger than those of the liver parenchyma, and the difference was statistically significant (P < 0.05). The difference was statistically significant (P < 0.05), while V1 and V2 of the tumor residual site were larger than the postoperative liver parenchyma, and the difference was statistically significant (P < 0.05). 4. After treatment, regular follow-up was performed by conventional ultrasound, enhanced CT and/or ultrasonography for at least 3 months, and enhanced CT was used as a criterion to judge the degree of tumor ablation. The complete tumor inactivation rate in the CEUS group was 89.5% (34/38), which was significantly higher than that in the control group (70.0% (28/40), and the difference was statistically significant (P < 0.05). 5. In the follow-up observation, there was no perfusion enhancement in the necrotic area. Conclusions: 1. CEUS performed before RFA treatment can confirm the actual size of liver tumor and the ablation treatment range, and more clearly show the size, morphology, boundary, infiltration range of tumor and the relationship with adjacent structures, which provides an important basis for determining the ablation range and selecting the choice of tumor radiofrequency treatment plan. 2. The quantitative parameter change characteristics of the ultrasonographic time intensity curve can quantitatively analyze and reflect the fine line between liver tumor, liver It is important for the timely evaluation of tumor residue, recurrence and follow-up after RFA, so as to enhance the effect of primary ablation and reduce the recurrence of tumor after RF treatment. 3. CEUS can promptly and accurately identify the coagulation caused by RF ablation after RFA. It is an effective method to evaluate the efficacy of RFA treatment.