Objective To observe the impact factors of vascular heat sink effect during in vitro microwave ablation(MWA)of porcine lung.Methods Simulation models were established using in vitro porcine lung tissue blocks based on isobaric inflation with an air pump and cyclic perfusion of duck blood with a glass tube and peristaltic pump,etc.MWA was performed under 8 different combining conditions(vessel diameter of 3 or 5 mm,blood perfusion of 30 or 50 cm/s,as well as distance between vessel and ablation antenna of 5 or 10 mm)each for 3 times.The highest temperature TV on vessel side and TC on control side during MWA,and ablation depth DV on vessel side and DC on control side after MWA were recorded.Multi-factor linear regression equations were constructed based on simulated vessel diameters,blood perfusion and distance between vessel and ablation antenna,and the impact factors of|TC-TV|and|DC-DV|were screened,respectively.Results Simulated vessel diameter showed linear positive correlation with both|TC-TV|and|DC-DV|(both P＜0.001).Simulated distance between vessel and ablation antenna showed linear negative correlation with both|TC-TV|and|DC-DV|(both P＜0.001),and the latter had more obvious impact on vascular heat sink effect than the former.Meanwhile,no significant linear relationship was found between simulated blood perfusion and|TC-TV|nor|DC-DV|(both P＞0.05).Conclusion Simulated vessel diameter and distance between vessel and ablation antenna were both impact factors of vascular heat sink effect during in vitro MWA of porcine lung,and the latter was more influential,whereas simulated blood perfusion showed no significant impact on it.

Objective To compare the efficacy and safety of flexible vacuum-assisted ureteral access sheath(FV-UAS)plus flexible ureteroscopic lithotripsy(FURL)and percutaneous nephrolithotomy(PCNL)in the treatment of 2-3 cm lower calyx stones,so as to provide reference for clinical treatment options of this type of stones.Methods A retrospective analysis was conducted on 114 patients with lower calyx stones admitted to our hospital during May 2021 and May 2024.Based on the surgical approaches,the patients were divided into the FV-UAS-FURL group(n=57)and PCNL group(n=57).The general data,biochemical indicators,operation time,complication rate,stone-free rate(SFR)and other clinical data of the two groups were compared.Results There were no significant differences in the general data,SFR 1 day(70.2％vs.59.6％,P=0.239)and 1 month(84.2％vs.78.9％,P=0.469)(P＞0.05)after the surgery between the PCNL group and FV-UAS-FURL group.Compared to the PCNL group,the FV-UAS-FURL group had greater decrease in hemoglobin level[1.00(-6.00,6.00)g/L vs.4.50(0,12.75)g/L,P=0.010],shorter operation time[87.0(60.5,121.5)min vs.112.0(90.0,122.5)min,P=0.004],shorter hospital stay[1.0(1.0,4.0)d vs.8.0(6.5,10.0)d,P＜0.001],and lower incidence of postoperative hematuria(15.8％vs.31.6％,P=0.047)and fever(5.3％vs.22.8％,P=0.007).Conclusion Both PCNL and FV-UAS-FURL can safely and effectively treat 2-3 cm lower calyx stones.However,FV-UAS-FURL has advantages over PCNL,including fewer postoperative complications,shorter operation time,and shorter hospital stay,making it a better surgical choice.

Objective To compare the efficacy and safety of CT-guided percutaneous radiofrequency ablation(RFA)and cryoablation(CRYO)combined with synchronous biopsy of pulmonary nodules.Methods Totally 62 patients with pulmonary nodules who underwent CT-guided percutaneous ablation with either RFA(n=30)or argon-helium CRYO(n=32)combined with simultaneous biopsy were enrolled,and the regarding postoperative complication rates and 1-year local control outcomes were compared.Results All patients successfully completed both ablation and biopsy procedures.In RFA group,the mean diameter of lesion was(1.43±0.33)cm,and the biopsy positive rate was 90.00%(27/30).Post-biopsy intrapulmonary hemorrhage extent immediately increased by 0.60(0.28,1.63)cm.Hemoptysis,pneumothorax requiring chest tube placement and infectious cavities observed in 2(2/30,6.67%),6(6/30,20.00%)and 4 cases(4/30,13.33%),respectively,and the 1-year local control rate in RFA group was 90.00%(27/30).In CRYO group,the mean diameter of lesion was(1.59±0.34)cm,and the biopsy positive rate was 100%(32/32).Post-biopsy intrapulmonary hemorrhage extent increased by 1.20(0.60,1.83)cm.Hemoptysis occurred in 7 cases(7/32,21.88%),and pneumothorax requiring chest tube placement was noticed in 8 cases(8/32,25.00%),while no infectious cavity was observed.The 1-year local control rate in CRYO group reached 96.88%(31/32).Statistical difference of infectious cavity was found between groups(P＜0.05).Conclusion Simultaneous biopsy during CT-guided percutaneous RFA and CRYO for lung nodules were both efficient and safe,while the former with relative higher incidence of infectious cavity.

Objective To compare the efficacy and safety of flexible vacuum-assisted ureteral access sheath(FV-UAS)plus flexible ureteroscopic lithotripsy(FURL)and percutaneous nephrolithotomy(PCNL)in the treatment of 2-3 cm lower calyx stones,so as to provide reference for clinical treatment options of this type of stones.Methods A retrospective analysis was conducted on 114 patients with lower calyx stones admitted to our hospital during May 2021 and May 2024.Based on the surgical approaches,the patients were divided into the FV-UAS-FURL group(n=57)and PCNL group(n=57).The general data,biochemical indicators,operation time,complication rate,stone-free rate(SFR)and other clinical data of the two groups were compared.Results There were no significant differences in the general data,SFR 1 day(70.2％vs.59.6％,P=0.239)and 1 month(84.2％vs.78.9％,P=0.469)(P＞0.05)after the surgery between the PCNL group and FV-UAS-FURL group.Compared to the PCNL group,the FV-UAS-FURL group had greater decrease in hemoglobin level[1.00(-6.00,6.00)g/L vs.4.50(0,12.75)g/L,P=0.010],shorter operation time[87.0(60.5,121.5)min vs.112.0(90.0,122.5)min,P=0.004],shorter hospital stay[1.0(1.0,4.0)d vs.8.0(6.5,10.0)d,P＜0.001],and lower incidence of postoperative hematuria(15.8％vs.31.6％,P=0.047)and fever(5.3％vs.22.8％,P=0.007).Conclusion Both PCNL and FV-UAS-FURL can safely and effectively treat 2-3 cm lower calyx stones.However,FV-UAS-FURL has advantages over PCNL,including fewer postoperative complications,shorter operation time,and shorter hospital stay,making it a better surgical choice.

Objective To compare the efficacy and safety of CT-guided percutaneous radiofrequency ablation(RFA)and cryoablation(CRYO)combined with synchronous biopsy of pulmonary nodules.Methods Totally 62 patients with pulmonary nodules who underwent CT-guided percutaneous ablation with either RFA(n=30)or argon-helium CRYO(n=32)combined with simultaneous biopsy were enrolled,and the regarding postoperative complication rates and 1-year local control outcomes were compared.Results All patients successfully completed both ablation and biopsy procedures.In RFA group,the mean diameter of lesion was(1.43±0.33)cm,and the biopsy positive rate was 90.00%(27/30).Post-biopsy intrapulmonary hemorrhage extent immediately increased by 0.60(0.28,1.63)cm.Hemoptysis,pneumothorax requiring chest tube placement and infectious cavities observed in 2(2/30,6.67%),6(6/30,20.00%)and 4 cases(4/30,13.33%),respectively,and the 1-year local control rate in RFA group was 90.00%(27/30).In CRYO group,the mean diameter of lesion was(1.59±0.34)cm,and the biopsy positive rate was 100%(32/32).Post-biopsy intrapulmonary hemorrhage extent increased by 1.20(0.60,1.83)cm.Hemoptysis occurred in 7 cases(7/32,21.88%),and pneumothorax requiring chest tube placement was noticed in 8 cases(8/32,25.00%),while no infectious cavity was observed.The 1-year local control rate in CRYO group reached 96.88%(31/32).Statistical difference of infectious cavity was found between groups(P＜0.05).Conclusion Simultaneous biopsy during CT-guided percutaneous RFA and CRYO for lung nodules were both efficient and safe,while the former with relative higher incidence of infectious cavity.

Objective To observe the impact factors of vascular heat sink effect during in vitro microwave ablation(MWA)of porcine lung.Methods Simulation models were established using in vitro porcine lung tissue blocks based on isobaric inflation with an air pump and cyclic perfusion of duck blood with a glass tube and peristaltic pump,etc.MWA was performed under 8 different combining conditions(vessel diameter of 3 or 5 mm,blood perfusion of 30 or 50 cm/s,as well as distance between vessel and ablation antenna of 5 or 10 mm)each for 3 times.The highest temperature TV on vessel side and TC on control side during MWA,and ablation depth DV on vessel side and DC on control side after MWA were recorded.Multi-factor linear regression equations were constructed based on simulated vessel diameters,blood perfusion and distance between vessel and ablation antenna,and the impact factors of|TC-TV|and|DC-DV|were screened,respectively.Results Simulated vessel diameter showed linear positive correlation with both|TC-TV|and|DC-DV|(both P＜0.001).Simulated distance between vessel and ablation antenna showed linear negative correlation with both|TC-TV|and|DC-DV|(both P＜0.001),and the latter had more obvious impact on vascular heat sink effect than the former.Meanwhile,no significant linear relationship was found between simulated blood perfusion and|TC-TV|nor|DC-DV|(both P＞0.05).Conclusion Simulated vessel diameter and distance between vessel and ablation antenna were both impact factors of vascular heat sink effect during in vitro MWA of porcine lung,and the latter was more influential,whereas simulated blood perfusion showed no significant impact on it.

Objective To investigate the CT-guided percutaneous irreversible electroporation (IRE) in treating locally advanced pancreatic cancer (LAPC) and providing guidance for its prevention and treatment. Methods We retrospectively analyzed the clinical and imaging data of 17 patients (17 lesions) of LAPC treated with CT-guided IRE in our hospital from July 2015 to June 2016. Complications were documented and reviewed at day 7,30 and 90 follow up as well as during the procedure. The Clavien?Dindo was used for classification. The reasons that induced complications were summarized and to further discuss the prevention and treatment approaches. Results Of 17 patients, 2 patients suffered a transient tachycardia during the procedure. Eleven patients (65%) showed complications at day 7, of which gradeⅠcomplications occurred in 6 cases, including abdominal pain, nausea, vomiting, or a few of inflammatory exudations around the pancreas; four patients have grade Ⅱ complications, along with portal vein thrombosis;one patient showed grade Ⅲ a complications for retroperitoneal infection. With 30 days follow up, the grade Ⅰ complications disappeared, gradeⅡcomplications have not getting better, while grade Ⅲ a complications have been improved. With 90 days follow up,patients with grade Ⅲ a complications getting better; two patients with grade Ⅱ complications didn't show any changes;2 cases progressed to grade Ⅴ, and died of digestive tract bleeding at 82 days and 98 days after procedure. Conclusion CT-guided irreversible electroporation for treating LAPC is a safe ablation approach. Strict patient selection before procedure and make a reasonable prevention and treatment measures can reduce the complications.

Objective To investigate the complications caused by CT-guided percutaneous radiofrequency ablations (RFA) for lung cancer and analyze the prevention approach. Methods A total of 125 lung cancer patients (142 RFA treatments) in our hospital were enrolled in this study between July 2015 and June 2017. This retrospective study analyzed the reasons and the strategies for preventing the complications. Results One hundred and twenty?five patients underwent RFA treatment for lung lesions. All the operations were successfully completed. During the treatment, 18 patients showed hemorrhage (3 of CTCAE grade 3 hemorrhage); 16 patients showed pneumothorax, among which, 15 patients have chronic obstructive pulmonary disease; 28 patients showed chest pain (23 cases were located under the pleura); 3 patients showed pneumonia;1 patient showed pulmonary abscess, which located in the subpleural space with a maximum diameter of ＞3 cm; 1 patient showed pulmonary embolism, and 1 patient with scald. Complications were attenuated after symptomatic treatment. Conclusion The main reasons of complications of RFA in treating lung cancer were direct injuries caused by punctures, tumors with abundant blood supplement, tumors adjacent to pleura, low scores of lung function, coagulation disorders, and diabetes. The key points for avoiding and reducing complications are preoperative evaluation of patients' basic situations, exclusion of intraoperative avoidable technical risk factors.

Nanoknife (irreversible electroporation) has demonstrated to be a safe and effective approach to tumor ablation,and plays a prominent role in application of treatment of pancreatic carcinoma,specifically locally advanced pancreatic carcinoma (LAPC).The complicated parameters of Nanoknife comparatively is still difficult.The advantage,optimal selection,adequate parameters regarding Nanoknife were reviewed in this article.

Objective To investigate the safety and efficacy of treatment with CT-guided percutaneous irreversible electroporation (IRE) of locally advanced pancreatic cancer(LAPC). Methods Patients with unresectable radiographic stage ⅢLAPC were prospectively collected. Comprehensive blood and imaging (CT,MRI,PET-CT) baseline examinations were completed and analyzed preoperatively. Operations were performed under general anesthesia and the needles were inserted under the guidance of CT. Ablative parameters were altered depending on the tumor size, anatomical location, and the number of electrodes. Needle withdrawal combined segmental ablation was chosen and the active electrode exposure length was 1 cm. All the imaging and serological follow-up examinations were performed within 1 to 3 days after procedures, at day 7 postoperatively, 1 and 3 months postoperatively to evaluate the safety and efficacy of IRE(according to modified response evaluation criteria in solid tumours of WHO). Results All the procedures were completed successfully. Immediately postoperative CT and/or MRI images showed all the ablation areas were well-defined and presented low-density necrosis without enhancement. The CT scans at day 7 postoperatively showed all the 14 lesions were drastically necrotized and the surrounding tissues were unharmed. CT and/or MRI scans at 1 month postoperatively revealed hypodense or low signal ablation areas without enhancement and the peritumoral and involved vessels and pancreatic duct were undamaged. All the patients had a CA199 transient rising, but it decreased progressively within 3 days and then markedly decreased at 1 weak and 1 month postoperatively. The laboratory carcino-embryonic antigen was almost within normal lists. Peripancreatic exudation was noted in 3 cases immediately after the procedures. One patient developed retroperitoneal infection. Mesenteric(2 of 4)and portal(2 of 4)venous thrombosis were found on MRI images in 4 patients. One patient had a duodenum stenosis and 1 died from serious gastrointestinal bleeding 2.5 months after IRE(unclear etiopathogenisis). The postoperative 3 months dynamic imaging showed that 4 of 13 reached complete response (CR) ,7 of 13 reached partial response (PR) and 2 of 13 had stable disease (SD). Conclusion CT-guided percutaneous IRE is safe and effective in patients with locally advanced pancreatic cancer.