模拟甲状腺囊实性结节囊性成分射频和微波消融的离体实验研究

目的探讨甲状腺囊实性结节射频和微波消融的可行性及效能。 方法使用目前常用的热消融方式（射频和微波）对甲状腺囊实性结节囊性成分的模拟液体（蒸馏水、生理盐水、血液、肝囊肿穿刺液和甲状腺囊实性结节穿刺液）进行消融。作用功率为目前临床常用的热消融功率（35 W和50 W）,每30 s记录温度值,连续监测10 min,绘制时间温度曲线。观察消融针针尖情况,记录针尖液体固化大小、形态及内部结构特点,必要时送病理检查。比较相同功率消融达到目标温度（60 ℃）的时间,并使用方差分析比较相同功率的射频和微波消融的热效能差异。 结果蒸馏水仅能进行微波消融,而无法进行射频消融。35 W射频消融在生理盐水、肝囊肿穿刺液中比微波消融较早达到消融目标温度［（171.4±3.9）s vs（343.6±5.7）s、（170.2±4.8）s vs（444.5±7.2）s］,时间温度曲线上具有较好的热效能（F=228.311、193.632,P均＜0.001）;50 W射频消融在肝囊肿穿刺液中比微波消融较早达到消融目标温度［（127.3±3.1）s vs（165.7±3.4）s］,时间温度曲线上具有较好的热效能（F=47.429,P＜0.001）;但射频消融在血液和甲状腺囊实性结节穿刺液中无法达到消融目标温度。而50 W微波消融能在所有模拟液体中达到消融目标温度,且在血液和甲状腺囊实性结节穿刺液中的热效能明显优于射频消融（F=47.429、22.859,P均＜0.001）。 结论微波消融能对各甲状腺囊实性结节囊性成分的模拟液体进行消融,且性能相对稳定。射频消融热效能较高,但对蒸馏水无法消融,对血液和甲状腺囊实性结节穿刺液因针尖容易形成积碳而效果不佳。     

热消融治疗甲状腺良性结节的疗效及相关因素分析

目的：探讨热消融治疗甲状腺良性结节的疗效,分析其影响因素。方法：回顾性分析86例在复旦大学附属中山医院接受热消融治疗的甲状腺结节患者的临床资料,随访消融1年后结节缩小率（volume reduction rate, VRR）,分析影响疗效（VRR）的相关因素。结果：消融1年后,结节体积由（12.3±7.3） mL缩小至（2.8±2.5） mL,VRR为（79.6±20.4）%。临床症状明显改善,美容评分和症状评分均较前下降（P<0.001）。多因素分析结果显示,男性获得的疗效优于女性,结节基线体积与VRR负相关,射频消融（RFA）疗效优于微波消融（MWA）,差异均有统计学意义（P<0.05）。结论：热消融治疗甲状腺良性结节效果较好,结节基线体积、消融方法和性别是影响消融疗效的独立因素。     

胆囊旁肝癌的微创治疗

目的评价腹腔镜下热消融治疗胆囊旁肝癌的安全性及疗效。方法采用腹腔镜胆囊切除术（LC）联合腹腔镜下经皮热消融治疗各类胆囊旁肝癌21例共32个病灶,术后复查肝功能、甲胎蛋白（AFP）、增强CT,观察疗效。结论手术前后Child-pugh评分无统计学差异;本组病例均无严重并发症和死亡病例;腹腔镜下（LUS）超声发现新病灶2例共2个;术前AFP升高的15例患者术后12例显著降低,3例无改变;术后四周复查增强CT,28个病灶完全消融,4个癌灶残留,再次行经皮热消融后达完全消融。随访12个月,2例复发（9．5％）。结论LC联合热消融使胆囊旁肝癌患者获得了安全、有效的微创治疗。     

超声引导下经皮热消融治疗囊性为主混合性甲状腺结节

目的探讨超声引导下经皮热消融治疗囊性为主混合性甲状腺结节的临床应用价值。 方法选取2016年6月至2017年8月于中国科学院大学附属肿瘤医院（浙江省肿瘤医院）超声科行超声引导下热消融治疗的甲状腺结节患者21例，对21例患者的23枚囊性为主混合性良性甲状腺结节进行超声引导下经皮射频（或微波）热消融治疗。于术后即时观察手术并发症情况，并于术后第3、6、12、18个月随访，超声测量结节体积，计算结节体积缩小率（VRR），分析热消融治疗效果。 结果21例患者在热消融过程中及术后均未出现明显血肿、出血及声音嘶哑、声音低沉、饮水呛咳等神经损伤征象。消融术后结节体积较术前呈进行性缩小，21例患者的23枚结节术后第3、6、12、18个月的VRR分别为0.733±0.045、0.823±0.039、0.904±0.034、0.933±0.026，差异有统计学意义（F=135.001，P<0.0001）。采用LSD-t方法两两比较，随访过程中各组VRR间比较，差异均有统计学意义（P均<0.01）。 结论超声引导下经皮热消融治疗囊性为主混合性甲状腺结节创伤小、安全性高、效果确切，尤其"搅拌消融法"为囊性为主混合性甲状腺结节的治疗提供了新思路，值得临床推广应用。     

羊胸腺微波消融的实验研究

目的探讨微波消融技术对羊胸腺组织的影响。方法利用微波消融治疗仪和发射段长5 mm、直径2mm的电极,分别以不同功率和时间对离体羊胸腺组织进行超声引导下消融,测量气化范围及消融灶大小,并进行病理学检查。分析消融灶大小与消融功率、时间的关系;观察微波消融后羊胸腺组织的病理变化,以及超声下气化范围和实际热损伤范围的大小关系。结果随着消融时间和功率的增加,气化区长径、短径和气化范围及消融灶长径、短径和消融灶面积均呈现增大趋势;同一消融功率、时间下,气化范围小于消融灶面积(P0.05);消融灶质地变硬,边界清晰,光学显微镜下,消融灶内胸腺组织形态失常,其内淋巴细胞难以辨认。结论微波消融功率、时间越大,超声气化范围和消融灶大小往往越大;微波消融羊胸腺组织的热损伤范围大于超声观察的气化范围,临床通过气化范围评估消融范围并不可靠。     

超声造影评估肝癌消融局部疗效价值的研究

目的评价超声造影判定肝癌消融局部疗效的价值。 方法对183例肝细胞性肝癌共248个结节行超声引导下经皮化学或热消融治疗，用超声造影判定局部疗效，造影剂为声诺维，使用低机械指数连续成像技术。以同期的增强CT或MRI作为金标准，作诊断性试验评估超声造影的判定效能。 结果增强CT或MRI判定78．2％（194／248）的病灶达到完全消融，21．8％（54／248）的肿瘤消融不全；超声造影判定79．O％（196／248）的病灶达到完全消融，21.0％（52／248）的病灶消融不全。同增强CT或MRI比较，超声造影诊断的敏感性、特异性、阳性预测值、阴性预测值、准确性分别为90．7％（49／54）、98．5％（191／194）、94．2％（49／52）、97．4％（191／196）、96．8％（240／248）。 结论超声造影判定肝癌消融局部疗效具有与增强CT或MRI同等的价值。     

动态三维超声造影在肝癌消融疗效评估中的初步研究

目的评价动态三维超声造影（3D-CEUS）在肝癌消融治疗后近期疗效中的诊断价值。方法对75例肝细胞肝癌共89个病灶行超声引导下经皮热消融或化学消融,治疗后1个月行动态3D-CEUS判定局部疗效,以同期对比增强CT（CECT）或对比增强MRI（CEMRI）作为金标准,评估动态3D-CEUS的诊断效能。结果 CECT或CEMRI判定80.9%（72/89）的病灶达到完全消融,19.1%（17/89）的肿瘤消融不全;动态3D-CEUS判定82.0%（73/89）的病灶达到完全消融,18.0%（16/89）的病灶消融不全。与CECT或CEMRI比较,动态3D-CEUS诊断的灵敏度、特异度、阳性预测值、阴性预测值和准确率分别为88.2%（15/17）、98.6%（71/72）、93.8%（15/16）、97.3%（71/73）和96.6%（86/89）。结论动态3D-CEUS在判定肝癌消融局部疗效中,与CECT或CEMRI具有同等的价值。     

射频消融与微波消融对离体牛肝作用的实验研究

目的：比较射频消融与微波消融对离体牛肝的作用效果。方法实验分为射频组与微波组,分别使用Cool-tip射频针与冷循环微波刀,均采用单针单次方式消融离体牛肝,比较两组间相同消融时间消融灶纵径、横径及体积。结果消融4、6、8 min,微波组消融灶纵径及体积均大于对应时间射频组消融灶纵径及体积（P＜0.05）,消融10 min,两组消融灶纵径及体积差异均无统计学意义（P＞0.05）;消融4 min,微波消融灶横径大于对应时间射频消融灶横径（P＜0.05）,消融6、8、10 min,两组消融灶横径差异均无统计学意义（P＞0.05）。结论与射频相比较,微波的热效率更高,消融速度更快,但随着消融时间延长,最终两者可取得相近的消融效果。     

超声影像评估组织热消融范围的研究进展

热消融作为一种有效治疗肿瘤的方法已广泛应用于临床,它是利用热能使肿瘤组织发生凝固性坏死从而达到杀伤肿瘤的作用,术中及术后准确评估热消融范围是降低复发率、减少正常组织损伤的前提。超声影像是目前评价组织热消融范围最常用的方法,本文就其评价组织热消融范围的具体方法和存在的主要问题等进行综述。     

超声引导下经皮微创消融治疗甲状腺结节的应用

超声引导下热消融治疗甲状腺结节是一种安全有效的微创介入治疗技术,可治疗多种类型的甲状腺结节。主要方法有射频、微波、激光消融及无水乙醇注射治疗等,目前以射频消融使用最为广泛。激光消融是近年来发展起来的一种新的微创治疗方法,关于甲状腺结节激光消融治疗的文献报道尚少。本文将对上述几种消融方法治疗甲状腺结节的优、缺点进行综述,推荐甲状腺结节的最佳治疗方法—激光消融,为以后的研究提供参考。      

Sonographically guided radio frequency thermal ablation for unresectable recurrent tumors in the retroperitoneum and the pelvis.

OBJECTIVE: To evaluate the feasibility of sonographically guided radio frequency thermal ablation as a minimally invasive method for treatment of unresectable recurrent or metastatic tumors in the retroperitoneum and the pelvis, which often pose difficult surgical problems. METHODS: Radio frequency thermal ablation was performed on 7 patients with unresectable recurrent retroperitoneal or pelvic tumors from colorectal (n = 4), renal (n = 2), and prostate (n = 1) cancers. Under sonographic guidance, a total of 11 radio frequency thermal ablation operations were performed by a percutaneous or transanal approach. RESULTS: Three patients were asymptomatic, whereas 4 patients were symptomatic. The sizes of the tumors ranged from 29 to 100 mm (mean, 50.5 mm). Radio frequency thermal ablation was technically completed in all operations without intraoperative complications. The ablation time ranged from 25 to 238 minutes depending on the tumor size. There was no mortality. There were postoperative complications in 3 operations (27.3%): an enterovesical fistula, a skin burn, and fecal incontinence. The hospital stay was generally 0 to 1 day. Tumor marker levels decreased after radio frequency thermal ablation in all operations. Symptoms of 4 patients were controlled by radio frequency thermal ablation. One patient with recurrent renal cancer and uncontrollable hypercalcemia became asymptomatic immediately after radio frequency thermal ablation. Local recurrence at the radio frequency thermal ablation site occurred in 2 patients (28.6%), but these local recurrent tumors were treated effectively by additional sonographically guided radio frequency thermal ablation. CONCLUSIONS: Minimally invasive sonographically guided radio frequency thermal ablation is technically feasible for local treatment of unresectable recurrent retroperitoneal and pelvic tumors from different origins. Care should be taken to avoid thermal injury to surrounding organs. Further study is needed to evaluate its safety and efficacy.     

腹腔镜下人工胸、腹水在特殊部位肝癌热消融中的应用

目的观察腹腔镜下人工胸、腹水在特殊部位肝癌热消融中应用的效果。方法回顾性分析中山大学附属第三医院2003年6月至2007年5月收治的肝癌并进行热消融的患者131例,其中肝癌位于肝脏被膜下有47例,根据是否采用腹腔镜下人工腹水或胸、腹水辅助超声引导将患者分为A、B两组,A组25例,采用腹腔镜下人工腹水或胸、腹水辅助超声引导肝脏被膜下肿瘤消融;B组22例,仅采用超声引导经皮肝脏被膜下肿瘤消融。比较两组患者术后肝被膜下血肿、腹腔内出血、胸腔积液、肝脓肿和肝功能损害等并发症的发生率、肿瘤完全消融率及1年复发率。结果A组出现胸腔积液1例,肝功能损害2例,并发症发生率为12.0%;B组肝被膜下血肿2例,腹腔内出血1例,胸腔积液5例,肝功能损害1例,并发症发生率为40.9%。两组并发症的发生率差异有统计学意义（χ^2=5.144,P=0.023）。A组和B组肿瘤完全消融率分别为96.8%和72.4%,两组肿瘤完全消融率差异有统计学意义（χ^2=5.194,P=0.023）;1年复发率差异无统计学意义（P〉0.05）。结论腹腔镜下人工胸、腹水辅助超声引导肝脏被膜下肿瘤热消融,以人工胸、腹水为媒介,结合了热消融与腹腔镜两项微创技术的优点,有效地提高了热消融治疗肝癌的效果,减少了并发症的发生,扩大了热消融治疗的适应证。     

Optimized nerve block techniques while performing percutaneous hepatic ablation: Literature review and practical use

Percutaneous image guided thermal ablation has become a cornerstone of therapy for patients with oligometastatic disease and primary liver malignancies. Evolving from percutaneous ethanol injection (PEI), thermal ablation utilizing radiofrequency ablation (RFA) and microwave ablation (MWA) have become the standard approach in the treatment of isolated lesions that fit within the size criteria for curative intent therapy (typically 3-4cm). With the evolution of more intense thermal ablation, such as MWA, the dramatic increase in both the size of ablation zone and intensity of heat generation have extended the limits of this technique. As a result of these innovations, intra-procedural and post-procedural pain have also significantly increased, requiring either higher levels of intravenous sedation or, in some institutions, general anesthesia.In addition to the increase in therapeutic intensity, the use of intravenous sedation during aggressive ablation procedures carries the risk of over-sedation when the noxious insult (i.e. the ablation) is removed, adding further difficulty to post-procedural recovery and management. Furthermore, high subdiaphragmatic lesions become challenging in this setting due to issues relating to sedation and compliance with breath hold/breathing instructions. Although general anesthesia may mitigate these complications, the added resources associated with providing general anesthesia during ablation is not cost effective and may result in substantial delays in treatment. The reduction of Aerosol Generating Medical Procedures (AGMP), such as intubation due to the COVID-19 Pandemic, must also be taken into consideration. Due to the potential increased risk of infection transmission, alternatives to general anesthesia should be considered when safe and possible.Upper abdominal regional nerve block techniques have been used to manage pain related to trauma, surgery, and cancer; however, blocks of this nature are not well described in the interventional radiology literature. The McGill University group has developed experience in using such blocks as splanchnic, celiac and hepatic hilar nerve blocks to provide peri-procedural pain control [1]. Since incorporating these techniques (along with hydrodissection with tumescent anesthesia), we have also observed in our high volume ablation center a dramatic decrease in the amount of sedatives administered during the procedure, a decrease in patient discomfort during localization and ablation, as well as decreased pain post-procedure. Faster time to discharge and overall reduction in room procedural time serve as added benefits.The purpose of this publication is to outline and illustrate the practical application and use of nerve block/regional anesthesia techniques with respect to percutaneous hepatic thermal ablation.     

Increased immunostimulatory activity conferred to antigen-presenting cells by exposure to antigen extract from hepatocellular carcinoma after radiofrequency thermal ablation

Radiofrequency thermal ablation represents an effective treatment for hepatocellular carcinoma (HCC) and it can also exert an "adjuvant" effect on spontaneous antitumor T-cell responses, as suggested by human and animal studies. The adjuvant effect is thought to depend on the huge amount of necrotic tumor antigen made available to the immune system by HCC thermal ablation. In addition, radiofrequency thermal ablation may result in the release of local stimuli responsible for activation and maturation of antigen-presenting cells (APCs). To test this hypothesis, we studied APC maturation and function in 19 patients undergoing thermal ablation for HCC. Patients' monocytes induced to differentiate with granulocyte macrophage colony-stimulating factor (GM-CSF), or GM-CSF plus IL-4, were cocultured in vitro with tumor debris generated by radiofrequency thermal ablation. Expression of costimulatory molecules, lymphnode homing chemokine receptor, antigen presentation, and cytokine secretion were enhanced by incubation with HCC treated tissue as compared with untreated HCC and nontumor liver tissue. Moreover, HCC-specific T-cell responses could be induced by monocytes activated with GM-CSF and incubated with thermally ablated HCC tissue. HCC thermal ablation can create an antigenic source along with stimuli appropriate for maturation of APCs to induce HCC-specific T-cell responses. These results contribute to explain at least in part the adjuvant effect of HCC thermal ablation and suggest a novel strategy to induce maturation of APCs and their loading with HCC antigens for active immunotherapy protocols aimed at reducing HCC recurrence after thermal ablation.     

Effect of Overpressure on Acoustic Emissions and Treated Tissue Histology in ex Vivo Bulk Ultrasound Ablation

Bulk ultrasound ablation is a thermal therapy approach in which tissue is heated by unfocused or weakly focused sonication (average intensities on the order of 100 W/cm²) to achieve coagulative necrosis within a few minutes exposure time. Assessing the role of bubble activity, including acoustic cavitation and tissue vaporization, in bulk ultrasound ablation may help in making bulk ultrasound ablation safer and more effective for clinical applications. Here, two series of ex vivo ablation trials were conducted to investigate the role of bubble activity and tissue vaporization in bulk ultrasound ablation. Fresh bovine liver tissue was ablated with unfocused, continuous-wave ultrasound using ultrasound image-ablate arrays sonicating at 31 W/cm² (0.9 MPa amplitude) for either 20 min at a frequency of 3.1 MHz or 10 min at 4.8 MHz. Tissue specimens were maintained at a static overpressure of either 0.52 or 1.2 MPa to suppress bubble activity and tissue vaporization or at atmospheric pressure for control groups. A passive cavitation detector was used to record subharmonic (1.55 or 2.4 MHz), broadband (1.2–1.5 MHz) and low-frequency (5–20 kHz) acoustic emissions. Treated tissue was stained with 2% triphenyl tetrazolium chloride to evaluate thermal lesion dimensions. Subharmonic emissions were significantly reduced in overpressure groups compared with control groups. Correlations observed between acoustic emissions and lesion dimensions were significant and positive for the 3.1-MHz series, but significant and negative for the 4.8-MHz series. The results indicate that for bulk ultrasound ablation, where both acoustic cavitation and tissue vaporization are possible, bubble activity can enhance ablation in the absence of tissue vaporization, but can reduce thermal lesion dimensions in the presence of vaporization.     

超声引导肝脾外伤局部热凝固消融治疗的研究进展

超声引导局部热凝固消融治疗是最有前途的肝脾外伤微创治疗新技术,而超声造影成像技术的发展使得这些新技术在肝脾外伤的治疗中更加实时准确。本文旨在综述超声引导下各种肝脾外伤局部热凝固消融治疗的研究进展。     

Real-Time Spatiotemporal Control of High-Intensity Focused Ultrasound Thermal Ablation Using Echo Decorrelation Imaging in ex Vivo Bovine Liver

The ability to control high-intensity focused ultrasound (HIFU) thermal ablation using echo decorrelation imaging feedback was evaluated in ex vivo bovine liver. Sonications were automatically ceased when the minimum cumulative echo decorrelation within the region of interest exceeded an ablation control threshold, determined from preliminary experiments as ?2.7 (log-scaled decorrelation per millisecond), corresponding to 90% specificity for local ablation prediction. Controlled HIFU thermal ablation experiments were compared with uncontrolled experiments employing two, five or nine sonication cycles. Means and standard errors of the lesion width, area and depth, as well as receiver operating characteristic curves testing ablation prediction performance, were computed for each group. Controlled trials exhibited significantly smaller average lesion area, width and treatment time than five-cycle or nine-cycle uncontrolled trials and also had significantly greater prediction capability than two-cycle uncontrolled trials. These results suggest echo decorrelation imaging is an effective approach to real-time HIFU ablation control.     

In Vivo Thermal Ablation Monitoring Using Ultrasound Echo Decorrelation Imaging

Previous work indicated that ultrasound echo decorrelation imaging can track and quantify changes in echo signals to predict thermal damage during in vitro radiofrequency ablation (RFA). In the in vivo studies reported here, the feasibility of using echo decorrelation imaging as a treatment monitoring tool was assessed. RFA was performed on normal swine liver (N = 5), and ultrasound ablation using image-ablate arrays was performed on rabbit liver implanted with VX2 tumors (N = 2). Echo decorrelation and integrated backscatter were computed from Hilbert transformed pulse-echo data acquired during RFA and ultrasound ablation treatments. Receiver operating characteristic (ROC) curves were employed to assess the ability of echo decorrelation imaging and integrated backscatter to predict ablation. Area under the ROC curves (AUROC) was determined for RFA and ultrasound ablation using echo decorrelation imaging. Ablation was predicted more accurately using echo decorrelation imaging (AUROC = 0.832 and 0.776 for RFA and ultrasound ablation, respectively) than using integrated backscatter (AUROC = 0.734 and 0.494).     

Thermal balloon endometrial ablation therapy induces a rise in uterine blood flow impedance: a randomized prospective color Doppler study.

OBJECTIVE: To evaluate the possible hemodynamic changes in uterine blood flow using transvaginal color Doppler ultrasonography after thermal balloon endometrial ablation therapy. STUDY DESIGN: Prospective randomized study. PATIENTS AND METHODS: Twenty-seven pre- and post-menopausal women with either menorrhagia or endometrial hyperplasia (no sign of atypia) were randomized to receive either thermal balloon ablation therapy (n = 13) or gestagen therapy (n = 14). In the gestagen therapy group, a 3-month period of medroxy-progesterone acetate (10 mg/day) was given to premenopausal women during cycle days 15-24 and it was given to postmenopausal women continuously. Thermal balloon endometrial ablation therapy was carried out on cycle days 3-8. All the color Doppler measurements were also carried out on cycle days 3-8. Flow waveforms were obtained from the main branch of the uterine arteries, from arcuate arteries and from a subendometrial spiral artery. Doppler flow parameters were used for subsequent statistical analysis. The measurements took place before the initiation of treatment, on the first postoperative day (thermal ablation group only), and 1 month and 6 months after initiation of the study. RESULTS: No within-group or between-group differences were detected until the time of the last measurement 6 months after initiation of the treatment. Between the two randomized groups, the pulsatility index (PI) was significantly higher in the thermal ablation group in all three arteries in comparison with the gestagen group, in which no change in the PI took place. In the thermal ablation group, a significant rise from the pretreatment level was observed in the PI in the uterine arteries and in the spiral artery 6 months after the therapy. CONCLUSION: Thermal balloon endometrial ablation therapy induces a rise in uterine blood flow impedance, but not until 6 months after the treatment. The rise in impedance may be due to fibrosis in the uterine cavity which thermal balloon therapy has been shown to produce.