Objective:To preliminarily explore the clinical value of three-dimensional ultrasound fusion imaging(3DUS FI) visualization technology in guiding precise needle placement during thermal ablation of hepatocellular carcinoma (HCC).Methods:A total of 56 HCC patients (59 lesions)who underwent 3DUS FI guided thermal ablation were retrospectively analyzed in the First Affiliated Hospital of Sun Yat-sen University from November 2019 to December 2021. All patients were collected with three-dimensional ultrasound volume image before ablation which were fused with real-time two-dimensional ultrasound image for registration, and then the tumor and the safety margin of 5 mm were segmented and marked. Finally, the thermal ablation was performed under three-dimensional visualization. Contrast-enhanced CT/MRI was performed 1 month after thermal ablation to evaluate whether the lesion was completely ablated and measure the ablative margin, and the relationship between ablative margin and the incidence of local tumor progression (LTP) was also analyzed.Results:During the ablation, all lesions could be successfully registered and displayed in three-dimension. Postoperative contrast-enhanced ultrasound showed that all lesions were completely ablated. A total of 37 lesions could be evaluated for ablative efficacy and ablative margin based on contrast-enhanced CT/MRI 1 month after themal ablation, of which 32 (86.5%) lesions achieved complete ablation and obtained at least 5 mm ablative margin. During the follow-up period, LTP was occurred in 4 lesions, 3 of the lesions occurred at the ablative margin< 5 mm. Both 1-year and 2-year cumulative LTP rates were all 7.1%. None of patients had serious complications or deaths associated with thermal ablation.Conclusions:3DUS FI real-time guidance technology is feasible and safe in visually guiding precise needle placement during thermal ablation of HCC.

Objective:To retrospectively summarize and evaluate the efficiency and safety of percutaneous ultrasound-guided radiofrequency ablation (RFA) for adrenal metastasis (AM) from hepatocellular carcinoma (HCC).Methods:From October 2009 to September 2018, 16 patients with AM from HCC who underwent percutaneous RFA in the First Affiliated Hospital of Sun Yat-Sen University were enrolled in the study. The complete ablation and local tumor progression rates were elevated, and the side effects and complications were summarized.Results:The median ablation time of AM was 16 min. The complete ablation rate was 87.5% (14/16). After the follow-up period of 3 to 55 months, among the patients with complete ablation, there were 3 patients were detected local tumor progression (LTP), the LTP rate was 21.4% (3/14). As for the side effects and complications, 3 patients were diagnosed as hypertension crisis (3/16, 18.8%), 2 showed reduced heart rate and 1 of them exhibited frequent premature ventricular contraction which resulted in termination of ablation. There was no ablation-related death or adrenal failure.Conclusions:Percutaneous US-guided RFA is safe and effective in the treatment of AM originated from HCC.

Objective To evaluate the effect of artificial ascites under ultrasonic guidance in the thermal ablation of liver or kidney tumors ,so as to provide basis for successfully creating artificial ascites , increasing the complete ablation rate of the tumors and reducing the damage of important organs . Methods Seven hundred and thirty-six patients with artificial ascites were performed under ultrasonic guidance during the thermal ablation of liver or kidney tumors and six hundred and seventy-nine patients were successfully performed . The success rate of creating artificial ascites at different sites ,time requirement ,the effect of ascites , puncture times were analyzed , while curative effect and complications were evaluated and summarized . Results The success rate of creating artificial ascites was 92 .3％ ;the average time of creating artificial ascites was( 9 .1 ± 1 .3) minutes ;the average puncture times was( 1 .1 ± 0 .2) times ;complete ablation was 98 .7％ ;the complication of ascites creation was 0 .44％ ,minor complications after ablation was 6 .20％ , severe complications was 0 .59％ . The required fluid volume and success rates for the creation of artificial ascites in different sites were different . The volume of fluid needed was relatively high in the liver-gastric space ,and the success rate was relatively low ;the success rate of liver septum and liver -kidney crypts was the highest . Heat injury complications of the important organs such as gastrointestinal tract ,esophagus , diaphragm near the liver or kidney tumors were 0 . Conclusions The establishment of artificial ascites improves the local curative effect and reduces the complication of tumors ablation in difficult locations . The methods and effect of artificial ascites in different parts of liver or kidney are different .

Objective To study the feasibility,efficacy and safety of ultrasound-guided percutaneous radiofrequency ablation (RFA) in the treatment of hepatocellular carcinoma (HCC) in the caudate lobe.Methods From November 2006 to June 2017,31 patients with 31 HCCs located in the caudate lobe were treated with percutaneous RFA at the First Affiliated Hospital of Sun Yat-sen University.The treatment efficacy,complications,and the local tumor progression (LTP),disease-free survival (DFS) and overall survival (OS) rates were analyzed.Results Residual tumors were detected in 5 patients after the first treatment.Complete necrosis was achieved in all the patients after the second treatment.The mean number of ablation sessions was 1.16±0.37.At a follow-up period which ranged from 3 to 65 months,19 patients had died,10 patients were still alive,and 2 patients were lost to follow-up.The 1-,2-,3-,and 5-years OS rates were 78.4％,48.5％,12.1％ and 12.1％,respectively.On follow-up,9 caudate lobe HCC lesions were detected to have LTP.The 1-,2-,and 3-years LTP rates were 21.5％,41.6％ and 41.6％,respectively;while the 1-,2-,and 3-years DFS rates were 22.3％,11.2％ and 11.2％,respectively.Ablationrelated complications were detected in 4 patients.Conclusions Ultrasound-guided percutaneous RFA was safe and effective for patients with HCC in the caudate lobe.These patients should be followed-up closely to detect LTP.

Objective To investigate the value of shear wave elastography (SWE) and quasi-static elastography in the evaluation of radiofrequency ablation of pork.Methods Twelve pieces of fresh pork were underwent radiofrequency ablation (RFA) with different target temperatures.Before and after RFA,conventional ultrasound (US),SWE and quasi-static elastography were conducted to visualize the boundaries of RFA zones.The size of ablation zones obtained from conventional ultrasound,SWE and quasi-static elastography measurement were observed and detected the correlativity with pathology findings.Moreover,the Young's modulus and stain ratio of ablated zone were recorded.Results Most ablated boundaries were clearly delineated by both elastography techniques,except one with a low target temperature of 70 ℃.The sizes of ablated zones measured by SWE and quasi-static elastography were closely correlated with pathological findings.However,no ablated zones could be visualized by conventional US.Before and after RFA,the mean,minimum and maximum values of Young's modulus were (24.2 ± 3.8) kPa vs (97.6 ± 29.1) kPa,(9.2 ± 0.7)kPa vs (44.5 ± 7.7)kPa and (29.9 ± 3.8)kPa vs (181.5 ± 36.7)kPa,respectively (all P ＜0.001).With the increase of target temperature of RFA,the Young's modulus values and the mean strain ratio were significantly increased (all P ＜ 0.01).Conclusions Both SWE and quasi-static elastography are useful tools for evaluating the ablation,which are superior to conventional US.Moreover,SWE can be used to monitor the procedure of ablation.

Objective To summarize the first experience with ultrasound-guided percutaneous ab lation treatment (PAT) for recurrent hepatoblastoma (HB) after liver resection in children.Methods From August 2013 to April 2015,PAT was used to treat 6 children with a total of 9 recurrent HB,including 5 patients with 8 tumors in the liver and 1 patient with 1 tumor in the lung.The mean size of ablated tumors was (1.5 ± 0.8) cm,and the tumor size range was 0.7 cm to 3.1 cm.Results Four patients were performed percutaneous radiofrequency ablation (RFA) for recurrent HB;and 2 patients were performed percutaneous ethanol injection (PEI).Ablation success was achieved in all patients (6/6,100％).The complete ablation rate after the first ablation session was 88.9％ (8/9) on a tumor-by-tumor basis.Only 1 patient developed a fever with temperature ＞ 39 ℃;it was resolved by conservative therapy.During the follow-up period of 5-30 months,3 patients died to tumor progression.The 1-and 2-year overall survival rates after ablation were 83.3％ and 41.7％,respectively.Conclusions PAT is a safe and promising therapy for children with recurrent HB after liver resection,and further investigation in large-scale randomized clinical trials is required to determine its role in the treatment of this disease.

Objective To retrospectively compare the safety and local efficacy of multiple-electrode switching based radiofrequency ablation (RFA) and the conventional RFA in treating single early-stage hepatocellular carcinoma (HCC).Methods A total of 82 patients with single early-stage HCC received either RFA with a multiple-electrode switching system (n =43) or conventional RFA (n =39) as the first-line treatment.The rate of initial local complete response,major complications and local tumor progression (LTP) were compared between two groups.Results The total ablation time was significantly shorter in the switching-RFA group [(16.7 ± 3.4) mins] than in the conventional RFA group [(29.8 ± 10.4) mins] (P ＜ 0.05).The rate of initial local complete response was 100％ (43/43) in the switching-RFA group and 94.9％ (37/39) in the conventional RFA group (P ＞0.05).After a mean follow-up period of (26.4 ± 21.8)months (ranging 3.0-91.6 months),the rates of LTP in the switching-RFA group and conventional RFA group were 16.3％ (7/43) and 17.9％ (7/39),respectively.The LTP rates in two groups were 16.1％ versus 11.2％ atyear1,and20.5％ versus 20.6％ at year2 (P=0.666).Conclusions The multiple-electrode switching based RFA is safe and effective with shorter ablation time in treating single early-stage hepatocellular carcinoma.

Objective To evaluate the safety and effective of ultrasound-guide percutaneous radio frequency ablation (RFA).Methods Retrospectively analyze the incident,management and influence factors of complication of ultrasound-guide percutaneous RFA.Results From 2001 to 2011,536 patients with 762 lesions underwent RFA were enrolled in this study.Incident of RFA complication was 2.03％ (11/536),including 5 (0.92％) major complication.The complication covered fever (1 case),massive hydrothorax (2 cases),hydrothorax accompany with ascites (1 case),massive ascites (1 case),liver abscess (1 case),liver capsule hemorrhage (1 case) and hemothrorax (1 case).No RFA relate mortality was observed.According to logistics regression analysis,the liver function Child-Pugh grading was associated with the RFA complication (P =0.005).Conclusions Ultrasound-guide percutaneous RFA is a safe and effective local treatment approach for hepatocellular carcinoma.It's necessary to comprehensively think over the basic condition of patients and the characters of tumor such as tumor location,size and abutting organs.Nevertheless,an appropriate treatment plan and closely monitor during and after RFA are crucial.

Objective To compare the features of different heating modes cauterization mode and standard ablation mode of Cool-tip on coagulation zone and thermal field distribution in order to provide references for focused and accurate vascular occlusion and explore the primary efficacy of Cool-tip applied to intrahepatic vascular occlusion in living dogs Methods Ex-vivo porcine livers were ablated for 2 4 6 8 minites with cauterization mode and standard ablation mode respectively and the long- and short-axis diameters in the greatest dimension were compared The tissue temperature around the tip midpoint and end of the exposed part of radiofrequency electrode were measured under the circumstance of 4 min ablation by the two modes respectively Animal experiment the intrahepatic vessels of 2 Beagles were ablated with cauterization mode one procedure for each animal and contrast-enhanced ultrasound was used to evaluate the perfusion change of liver tissue Gross anatomy and pathological examination of the liver was performed after 1 week Results In the 2 min 4 min 6 min and 8 min ablation the coagulation volume of cauterization mode and standard ablation mode were 1 01 ± 0 41 cm 3 vs 2 95 ± 0 74 cm 3 1 47 ± 0 33 cm 3 vs 5 03±1 06 cm 3 2 29±0 49 cm 3 vs 9 23±2 53 cm 3 2 70±0 24 cm 3 vs 1 5 89±0 77 cm 3 The coagulation volume was significant smaller in cauterization mode than in standard ablation mode P <0 05 for all The peak temperature of cauterization mode presented on the tip of electrode which averaged 94 4℃ in maximum and maintain around 70 ℃ in the equilibrium phase The peak temperature of standard mode presented on the midpoint of the electrode which periodically variated between 70 ℃- 100 ℃ The result of the animal experiment showed that cauterization mode could be used to occlude the intrahepatic vessel in vivo which induced the ischemia and necrosis in the corresponding area Conclusions Cauterization mode and standard alation mode of Cool-tip have different characteristic in terms of coagulation zone and thermal distribution and carterization mode may have a promising application in intrahepatic vascular occlusion.

Objective To investigate the influencing factors of quality of shear wave elastography (SWE) image and the reproducibility of using SWE for focal liver lesions .Methods A total number of 289 consecutive patients with 305 lesions (the lesions could be detected on baseline ultrasound with intercostals approach ,and the depth of lesion was less than 10 cm) were undergone SWE examination .The SWE values of both lesion and adjacent liver parenchyma were measured .The quality of images was classified into three grades:“Good” ,“Common” ,and “Poor” .The depth of lesion ,the distance from body surface to liver capsule ,diameter and location of lesion were compared among three groups .Twenty consecutive patients with 20 lesions were performed SWE by two operators and another 20 consecutive patients with 20 lesions were performed SWE by one operator at different time .Intra‐class correlation coefficient was used to evaluate the reproducibility of inter‐ and intra‐ observer .Results A total number of 179 lesions were“Good” ,107“Common” and 19 “Poor” .The distance from body surface to liver capsule was significantly different among three groups [(Good (1 3.4 ± 0 3.5)cm ,Common (1 6.3 ± 0 3.6)cm ,Poor (1 8.7 ± 0 3.9)cm , P < 0 0.01] .No significant difference was found for the depth ,diameter and location of lesions among three groups .For all parameters of SWE both lesion and adjacent parenchyma ,intra‐class correlation coefficient of inter‐and intra‐observer were higher than 0 7.5 .The reproducibility of max SWE value was best of four elasticity parameters for lesion ,which intra‐class correlation coefficient of inter‐and intra‐observer was 0 9.0 and 0 9.6 ,respectively .Conclusions For focal liver lesions which could be detected on baseline ultrasound and the depth of lesions was less than 10 cm ,SWE could be used to evaluate elasticity characteristics with good feasibility and reproducibility .