Radio-frequency ring applicator: energy distributions measured in the CDRH phantom

SAR distributions were measured in the CDRH phanton, a 1 cm fatequivalent shell filled with an abdomen-equivalent liquid (σ=0.4−1.0 S m⁻¹; dimensions 22×32×57 cm) to demonstrate the feasibility of the ring applicator to obtain deep heating. The ring electrodes were fixed in a PVC tube; diameter 48 cm, ring width 20 cm and gap width between both rings 31.6 cm. Radio-frequency energy was fed to the electrodes at eight points. The medium between the electrodes and the phantom was deionised water. The SAR distribution in the liquid tissue volume was obtained by a scanning E-field probe measuring the E-field in all three directions. With equal amplitude and phase applied to all feeding points, a uniform SAR distribution was measured in the central cross-section at 30 MHz. With RF energy supplied to only four adjacent feeding points (others were connected to a 50 ω load), the feasibility to perform amplitude steering was demonstrated; SAR values above 50% of the maximum SAR were measured in one quadrant only. SAR distributions obtained at 70 MHz showed an improved focusing ability; a maximum at the centre exists for an electric conductivity of the abdomen-equivalent tissue of 0.6 and 0.4 S m⁻¹.     

射频消融治疗快速心律失常428例总结

目的：报告射频消融术（RFCA）治疗快速心律失常的经验。方法：分析本院428例RFCA患者资料，其中房室结折返性心动过速（AVNRT）127例，房室折返性心动过速（AVRT）261例，特发性室性心动过速（IVT）28例，阵发性心房扑动（PAF）9例，房性心动过速（AT）3例。结果：消融总成功率96．9％（其中AVNRT97．6％，AVRT97．4％，IVT82．1％，PAF77．8％，AT100％），总复发率4．6％（其中AVNRT2．4％，AVRT4．3％，IVT 17．4％，PAF 14．3％），并发症发生率o．9％，无致命并发症出现。结论：RFCA治疗快速心律失常成功率高，并发症少，是安全有效的根治方法。     

超声联合1,6-二磷酸果糖醛缩酶在肝癌射频治疗中的监测作用

目的：探讨超声联合血清1，6-二磷酸果糖醛缩酶（fructose 1,6-dipbosphate aldolase,FDP-ALD)等指标在原发性肝癌（hepaucellular carcinoma,HCC)射频消融（radio-frequencs,RF)治疗中的监测作用。方法 HCC14例共14个肿瘤结节行RF治疗，治疗前后行超声检查，检测不同时点的血清FDP-ALD，甲胎蛋白（AFP）等指标并进行比较。结果 术后第1d FDP-ALD达最高值，随后呈直线下降，血清AFP术前及术后的分布与之一致。结论 血清FDP-ALD活性变化可反映HCC组织的坏死程度，超声联合血清FDP-ALD活性测定可作为HCC消融治疗中的监测方法。     

经导管动脉化疗栓塞联合经皮射频消融治疗中央型非小细胞肺癌

目的探讨TACE联合经皮射频消融(PRFA)治疗中央型非小细胞肺癌(CNSCLC)的临床疗效及其安全性。方法回顾性分析41例不可手术切除的中晚期CNSCLC患者(共50个病灶),均接受肿瘤供血动脉TACE治疗(化疗方案:吉西他滨1 000mg+顺铂90mg;栓塞材料:Embosphere微球),并于术后5天接受PRFA治疗肿瘤。术后以增强CT随访观察肿瘤大小及其强化情况,并根据改良实体肿瘤疗效评价标准评价联合治疗效果,计算术后3、6、12个月的客观有效率(ORR)。通过Kaplan-Meier生存分析获得患者术后无进展生存时间(PFS)。观察并记录术后并发症情况。结果对所有患者均成功完成TACE及PRFA治疗。术后3、6、12个月ORR分别为92.68%(38/41)、78.05%(32/41)和68.29%(28/41)。患者中位PFS为14.8个月。32例发生术后并发症,包括胸疼13例、气胸8例、少量咯血6例、血胸3例、喉返神经损伤1例、胸膜反应1例,均较轻微,可自行缓解或经对症处理后好转,未出现脊髓损伤、大咯血及大量血气胸等严重并发症。结论 TACE联合PFRA为治疗中晚期CNSCLC的有效方法,且安全性较高。     

Does acute radio-frequency electromagnetic field exposure affect visual event-related potentials in healthy adults?

Objective

To use improved methods to address the question of whether acute exposure to radio-frequency (RF) electromagnetic fields (RF-EMF) affects early (80–200?ms) sensory and later (180–600?ms) cognitive processes as indexed by event-related potentials (ERPs).

Safety and efficacy of endoscopic ultrasound-guided radiofrequency ablation for pancreatic insulinoma: A single-center experience

Background/objectivesInsulinomas are rare, functioning pancreatic neuroendocrine neoplasms (pNEN), whose gold standard therapy is surgical resection. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is a recent technique that has emerged as a minimally invasive therapeutic option for patients with pancreatic lesions not eligible for surgery. In this study, we aimed to describe a series of patients with unresectable pancreatic insulinoma treated with EUS-RFA.MethodsThis is a single-center, retrospective study including all consecutive patients with functioning pancreatic insulinoma undergoing EUS-RFA for surgical unfitness or surgery refusal, between March 2017 and September 2021. Technical success (i.e., complete mass ablation), adverse event rate and severity, clinical and radiologic outcomes (i.e., symptom remission with a normal concentration of blood glucose, and the presence of intralesional necrosis), and post-procedural follow-up were assessed.ResultsA total of 10 patients (mean age: 67.1 ± 10.1years; F:M 7:3) were included. The mean size of insulinoma was 11.9 ± 3.3 mm. Technical success and clinical remission were achieved in 100% of patients. Only one (10%) patient was successfully treated with two RFA sessions. Two procedure-related early adverse events occurred, including two (20%) cases of mild abdominal pain. No major complications were observed. The complete radiologic response within 3 months after EUS-RFA was observed in all patients (100%). After a median follow-up of 19.5 (range12–59) months, symptom remission and persistent euglycemia were assessed in all the patients.ConclusionsData from this case series suggest that EUS-RFA is a feasible and safe therapeutic approach for pancreatic insulinomas in patients unwilling or unable to undergo surgery with medium-term efficacy.