Monopolar Radiofrequency Ablation Research Articles

Model for predicting the recurrence of atrial fibrillation after monopolar or bipolar radiofrequency ablation in patients with AF and mitral valve disease

ObjectivesThis study aimed to identify the risk factors for postoperative atrial fibrillation in patients with valvular atrial fibrillation, and establish predictive models of atrial fibrillation recurrence.MethodsOverall, 224 patients who underwent radiofrequency ablation of atrial fibrillation from November 2014 to November 2020 were included. The statistical package for social sciences, X-tile, and R-studio were used for statistical analysis.ResultsPatients were divided into training and validation sets according to a ratio of 3:1. The training set was analysed using univariate and multivariate Cox regression analysis and showed that preoperative uric acid > 401 μmol/L (P = 0.006), B-type natriuretic peptide > 202 ng/L (P = 0.042), hypersensitivity C-reactive protein > 6.1 mg/L (P = 0.026), erythrocyte sedimentation rate > 7.0 mm/h (P = 0.016), preoperative left atrial diameter > 48 mm (P = 0.031) were significantly correlated with the recurrence of atrial fibrillation after radiofrequency ablation in patients with valvular atrial fibrillation. In the training set, a Cox regression model of the five related factors was established using the R language. The C-index of the model was 0.82, and the area under the receiver operating characteristic curve was 0.831 (P < 0.001). Internal and external verification was performed in the training and validation sets, respectively, and both showed that the fit of the verification curve was relatively good at 3 months, 6 months, 1 year, and 3 years postoperatively. After calculating the weight of each related factor using the nomogram, a new risk predictive model (BLUCE) for postoperative atrial fibrillation was established.ConclusionsIn patients with atrial fibrillation, preoperative uric acid, B-type natriuretic peptide, hypersensitivity C-reactive protein, erythrocyte sedimentation rate, and left atrial diameter are risk factors for atrial fibrillation or atrial flutter recurrence after radiofrequency ablation. The BLUCE predictive model can distinguish high-risk groups of postoperative atrial fibrillation. High-risk patients in the BLUCE model were more likely to experience recurrence of atrial fibrillation after radiofrequency ablation and a low possibility of maintaining sinus rhythm.

Long-term oncological results of percutaneous radiofrequency ablation for intrahepatic cholangiocarcinoma.

The effectiveness of percutaneous radiofrequency ablation (RFA) in intrahepatic cholangiocarcinomas (iCCA) remains insufficiently studied. We conducted a retrospective study including patients with histologically proven iCCA within Milan criteria treated by percutaneous RFA from 2000 to 2022. The primary outcome was overall survival in treatment-naive patients and secondary outcomes included ablation completeness, adverse events, local and distant recurrence. A total of 494 patients with hepatocellular carcinoma (HCC) on cirrhosis treated by RFA were included as a comparison group. Oncological events were analysed using Kaplan-Meier, log-rank and univariate/multivariate Cox models. The main population included 71 patients, mostly cirrhotic (80%) with solitary tumours (66%) of a median size of 24 mm. Local recurrence was 45% at 5 years, lower in multibipolar versus monopolar RFA (22% vs. 55%, p = .007). In treatment-naive patients (n = 45), median overall and recurrence-free survivals were 26 and 11 months, respectively. Tumour size (p = .01) and Child-Pugh B (p = .001) were associated with death. The rate of distant recurrence was 59% at 5 years significantly lower for single tumours of less than 2 (p = .002) or 3 cm (p = .02). In cirrhotic patients naïve of previous treatment (n = 40), overall survival was shorter than in HCC (26 vs 68 months, p < .0001), with more local recurrences (p < .0001). Among distant recurrences, 50% were extrahepatic metastases compared to 12% in HCC (p < .001). Multibipolar RFA provides better results in terms of tumour recurrence than monopolar RFA and could be used to treat small iCCA (<3 cm). Adjuvant chemotherapy should be discussed due to the frequent extra-hepatic metastasis at recurrence.

Cardiac Radiofrequency Ablation Exacerbates Myocardial Injury through Pro-Inflammatory Response and Pro-Oxidative Stress in Elderly Patients with Persistent Atrial Fibrillation.

There is a need to assess myocardial damage after radiofrequency ablation of the pulmonary veins (PV) for persistent atrial fibrillation (PAF) in elderly patients. To evaluate oxidative stress, inflammatory response and myocardial damage in elderly patients with PAF after radiofrequency ablation of the PV. High-sensitivity troponin T (hsTnT), malondialdehyde-modified low-density lipoprotein (MDA-LDL), acrolein (ACR), lipid hydroperoxide (LHP), toll-like receptor 4 (TLR4), soluble growth stimulation expressed gene 2 (sST2), angiotensin II (Ang II) and myocardial blood flow (MBF) were determined before ablation and at 1, 3 and 5 months after radiofrequency ablation. The levels of hsTnT, MDA-LDL, ACR, LHP, TLR4, sST2 and Ang II were increased 3 months after ablations compared with before ablation and 1 month after ablation, respectively (P<0.001); they were further increased at 5 months after ablation compared with the 1- and 3-month groups, respectively (P<0.001). MBF was decreased in the 3 months group after ablations compared with before ablation and 1-month after ablation, respectively (P<0.001), and was further decreased in 5-months after ablations compared with 1-month and 3-month groups, respectively (P<0.001). Patients with epicardial monopolar radiofrequency ablation had higher levels of hsTnT, MDA-LDL, ACR, LHP, TLR4, sST2, Ang II and lower MBF than patients with endocardial monopolar and bipolar radiofrequency ablations, respectively (P<0.001). Monopolar radiofrequency ablation method could result in more myocardial injury than bipolar radiofrequency ablation. Oxidative stress and inflammatory response may be involved in cardiac radiofrequency ablation-induced myocardial injury, resulting in myocardial ischemia in elderly patients with PAF.

Bipolar radiofrequency ablation of genicular nerves in chronic knee pain: A novel technique for more complete sensory denervation.

Monopolar radiofrequency ablation (MRFA) of the genicular nerves has been considered the main interventional treatment for chronic knee pain. However, the variable locations of these nerves could suggest that traditional MRFA of genicular nerves may be insufficient to cover the area needed to provide complete sensory denervation. For these reasons, some alternatives have been proposed to achieve an increase in the lesion area that offers better outcomes such a bipolar radiofrequency ablation (BRFA). To describe the efficacy and safety of the bipolar radiofrequency ablation (BRFA) of the genicular nerves in the patients with chronic knee pain. A retrospective study was conducted in the Pain Medicine Department. Institutional review board approval from the Hospital Ethical Committee and informed consent were obtained. We reviewed our database for BRFA of genicular nerves from January 2018 to December 2021 for patients with chronic knee pain. The cannulas were placed using ultrasound guidance (10cm, 22-gauge and 10mm active curved tip), and each pair of cannulas were subjected to BRFA for 90 seconds at 80∘C. Data analysis was conducted using T-test for paired variables (Visual analogue scale and EuroQol, an instrument intended to complement other forms of quality-of-life measures). Twenty-five patients met inclusion criteria after excluding 7 based on the study design. The mean improvement of our patients according to the VAS was -3.98 (95%CI: -4.37 to -3.59) p< 0.0001 and EuroQol +0.416 (95%CI: 0.364 to 0.468) p< 0.0001. The mean duration of improvement was 8 (6-11) months after BRFA. There were no reported serious adverse events related to the procedure, only local pain for 24 to 48 hours in 3 patients. We can conclude that BRFA reduces procedural pain and increases the treatment area, providing more complete sensory denervation and improved clinical outcomes.

Bipolar Radiofrequency Ablation for Neuropathic Pain in a Patient with a Morton Neuroma of Atypical Location

Introduction: Morton's Neuroma is a common cause of forefoot pain, often resulting from excessive force and compressive footwear, especially in highly active patients. The treatment typically begins with physical therapy and modifications in activity or footwear, progresses to corticosteroid and alcohol injections, and ultimately may involve surgical management. Bipolar radiofrequency ablation (RFA) is an emerging treatment that might delay or prevent surgery and may be more effective than its monopolar counterpart. The aim of this case report is to highlight bipolar radiofrequency ablation as a potential treatment option for Morton's neuroma (MN). Case Presentation: The author’s present a 70-year-old male with a clinical diagnosis of Morton's neuroma in an unusual location who underwent bipolar RFA on the medial side of the left great toe after conservative therapy proved unsuccessful. Following the procedure, the patient showed substantial improvement both functionally and symptomatically, with a notable reduction in pain by 70% at his 3-week check-up. Conclusion: Radiofrequency ablation is increasingly being recognized as a valuable option in the pain management toolkit for Morton's Neuroma. The benefits of delaying or avoiding surgery are particularly significant for athletes and dancers. Compared to monopolar RFA, bipolar RFA may provide a more effective treatment.

Combined Ultrasound and Computed Tomography Guidance in Radiofrequency Ablation for Hepatocellular Carcinoma Reduces Local Recurrence Rate

Background/Aim: In radiofrequency ablation (RFA) treatment of hepatocellular carcinoma (HCC), the therapeutic effect depends on the appropriate position of the electrode. To improve the accuracy of the electrode needle position, we currently perform RFA with combined ultrasound sonography (US) and computed tomography (CT) guidance. The purpose of this study was to evaluate the effectiveness of this US/CT-guided RFA method. Patients and Methods: This retrospective study recruited 97 patients with single tumors treated with transcatheter arterial chemoembolization and monopolar RFA between January 2013 and December 2017. Among these, 50 patients were treated with RFA under US/CT guidance (US/CT-guided group) and 47 were treated with RFA under US guidance alone (US-guided group). We analyzed the efficacy of US/CT guidance compared with US guidance alone. Results: The 1-, 2-, and 3-year local recurrence rates for the US/CT-guided and US-guided groups were 4.1%, 6.3%, and 8.6%, and 19.6%, 31.6%, and 41.9%, respectively. The local recurrence rate was lower in the US/CT-guided group (p=0.0030). Cox proportional hazards model for multivariate analysis demonstrated that the independent risk factors associated with local recurrence were tumor size (p=0.0028) and US/CT guidance (p=0.0037). Conclusion: US/CT-guided RFA for HCC reduced the local recurrence rate compared with US-guided RFA alone.

Retracted: Clinical Efficacy of Interventional Chemotherapy Embolization Combined with Monopolar Radiofrequency Ablation on Patients with Liver Cancer.

[This retracts the article DOI: 10.1155/2022/2306451.].

A randomized controlled study of the long-term efficacy of cooled and monopolar radiofrequency ablation for the treatment of chronic pain related to knee osteoarthritis

BackgroundChronic knee pain due to osteoarthritis (OA) is expected to become more prevalent. Although conventional therapies may provide relief they are not long-lasting. Persistent pain may lead to total knee replacement, which is not free of adverse outcomes. Monopolar and cooled radiofrequency ablation (RFA) of genicular nerves is an effective option. However, either method may provide distinctive results depending on expected lesion size, a key aspect considering the anatomical variability of knee innervations. This prospective, double-blind, randomized controlled trial evaluated the efficacy and durability of knee RFA using a cooled probe or a monopolar probe of comparable diameter. MethodsThis investigator-initiated, post-market, double-blinded, prospective, randomized controlled trial was approved by the Western IRB. 79 subjects with chronic knee pain due to knee OA were enrolled in multiple locations of a single center. 75 subjects were randomized (1:1) into RFA treatment with either a 4 ​mm/17G cooled active tip (CRFA) or a 10 ​mm/16G monopolar active tip (MRFA) using conventional procedures. Primary endpoint was change in knee pain level (100 ​mm VAS score) from baseline at 24-week post-treatment. Other endpoints include change in functionality, global perceived effect, and frequency of adverse events. Evaluation spanned to 52-week post-treatment. Significance of results (p ​< ​0.05) was calculated using standard statistical analyses. ResultsBoth CRFA and MRFA provided significant reduction (41 ​mm and 39 ​mm, respectively) of chronic knee pain at 24-week. At the 52-week visit, reduction in pain level was sustained for CRFA (42 ​mm) but seems to decrease for MRFA (31 ​mm). Improvements in functionality were also significant and sustained with both treatments, although tend to decrease with MRFA at 52-week. Most patients also perceived a very good/good effect of treatments along the duration of the study. ConclusionRFA of knee genicular nerves for the treatment of OA chronic pain is effective for 52 weeks post-ablation when using a CRFA (4 ​mm/17G active tip) or MRFA (10 ​mm/16G active tip). The benefits of CRFA seems to be better sustained beyond 24 weeks than the ones of MRFA, although no significant differences were observed at 52 weeks.

Results of Surgical Ablation for Atrial Fibrillation in Patients with Rheumatic Heart Disease.

There is conflicting evidence regarding the success of the Maze procedure to restore sinus rhythm in patients with rheumatic heart disease. Hence, the aim of our study was to describe the results of surgical ablation for atrial fibrillation in patients with rheumatic heart disease undergoing cardiac surgery. This is a retrospective study that included adult patients with rheumatic heart disease who underwent surgical ablation for atrial fibrillation. The ablation lesions were performed using monopolar radiofrequency ablation in all patients. Fifty-seven consecutive patients were included in the study. Cox Maze IV was performed in 44 patients (77%), while left-sided surgical ablation was performed in 10 patients (17%) and pulmonary vein isolation in 3 patients (5%). The percentage of patients who were in sinus rhythm on discharge, at 1-month, at 3-months, 6-months and 12-months follow up were 56%, 54%, 52%, 56% and 46% respectively. Complete heart block occurred in 21 patients (44%), but only 15 of them (26%) required permanent pacemaker insertion. Freedom from composite endpoint of death, stroke, and readmission for heart failure was 78% at one-year follow up. Despite the suboptimal rates of sinus rhythm at the intermediate and long term follow up, surgical ablation of atrial fibrillation in patients with rheumatic heart disease should continue to be performed. Continuation of Class III antiarrhythmic medications and early intervention for recurrent atrial fibrillation is crucial to the success of this procedure and for maintenance of higher rates of sinus rhythm at intermediate and long-term follow up.

The Effect of Local Anesthetics and Contrast Agents on Radiofrequency Ablation Lesion Size.

Radiofrequency ablation (RFA) is a validated treatment option for the treatment of chronic pain in patients with lumbar spondylosis. Lesion size has been suggested to correlate with good clinical outcomes. This has created an abundance of scientific interest in the development of products with larger lesion characteristics. Needle characteristics, energy transfer, and heat rate are known to modify lesion size. Here, we demonstrate that common intraoperative solutions, such as lidocaine, iodine, and gadolinium-based products, can also affect lesion shape. To determine whether lidocaine and contrast agents modify lesion characteristics during the performance of monopolar RFA. Controlled, ex vivo study using clinically relevant conditions and pre-injections. Academic institution in a procedural setting. RFA lesion size was compared among six cohorts: 1) lidocaine 1%, 2) lidocaine 2%, 3) iohexol 180, 4) iohexol 240, 5) gadodiamide, and 6) control (no fluid control). Radiofrequency (RF) current was applied for 90 seconds at 80°C via 20-gauge 100-mm standard RFA needles with 10-mm active tips in orgranic chicken breasts without preservative at room temperature (21°C). Twelve lesions were performed for each medication cohort. The length, width, and depth of each lesion were measured. The statistical significance between each medication group and the control group was evaluated by t test. The mean lesion surface area of monopolar RFA without any pre-injection used was 80.8 mm2. The mean surface area of the monopolar RF lesion with a pre-injection of 0.2 mL of 2% lidocaine was 114 mm2, and the mean surface area of the monopolar RF lesion with a pre-injection of 0.2 mL of iohexol240 was 130.6 mm2. The statistical analysis demonstrated that the control group had significantly smaller lesion sizes than did the groups in which lidocaine 2% and iohexol240 were used (P<0.01). There were no statistically significant differences among the groups in which lidocaine 1%, iohexol180, and gadodiamide were used. A notable difference was a 20% longer lesion with iohexol240 compared with the control group and a 20% wider lesion with lidocaine 2% compared with the control group. In vivo anatomy within a human was not used in this study, nor were the chicken breasts heated to physiological temperature. Randomization of pieces of chicken breast did not occur, and thus intrinsic differences among the chicken breast pieces could play a confounding role. Lidocaine 2% and iohexol240, when used as pre-injections in RFAs, were found to be associated with statistically significant increases in lesion surface area. However, RFAs with lidocaine 1%, iohexol180, or gadodiamide were not found to produce a statistically significant difference in lesion size compared with monopolar RFA without the use of injectate.

Radiofrequency Ablation of the Infrapatellar Branch of the Saphenous Nerve for the Treatment of Chronic Anterior Inferomedial Knee Pain.

Genicular nerve radiofrequency ablation (GNRFA) is an effective treatment for chronic knee pain related to osteoarthritis. It is often utilized when conservative management has failed and patients wish to avoid arthroplasty, are poor surgical candidates due to comorbid medical conditions, or in those suffering from persistent pain after arthroplasty. The classic targets for GNRFA include the superior lateral genicular nerve, superior medial genicular nerve, and inferior medial genicular nerve but multiple anatomic studies have demonstrated additional sensory innervation to the knee. In this research article, we propose an image-guided technique that can safely target the infrapatellar branch of the saphenous nerve which also provides sensory innervation to the anterior capsule. The proposed technique includes variations for conventional bipolar radiofrequency ablation, cooled radiofrequency ablation, dual-tined bipolar radiofrequency ablation, and monopolar radiofrequency ablation using a long axis approach. The described technique is based on updated anatomic studies and takes into account safety concerns such as thermal risk to the skin and/or pes anserine tendons and breaching of the synovial cavity. Future clinical research should be performed to confirm the safety and effectiveness of this specific approach.

Ultrasound-guided monopolar versus bipolar radiofrequency ablation for genicular nerves in chronic knee osteoarthritis pain: A randomized controlled study

BackgroundThis study compared between monopolar and bipolar radiofrequency (RF) ablation of the genicular nerves using ultrasound guidance (USG) in chronic knee osteoarthritis pain. Material and methodsThis was a prospective, randomized, double-blind study. Fifty patients with knee osteoarthritis pain were equally randomized to either monopolar or bipolar groups. The primary outcome was visual analogue score (VAS). The secondary outcomes were the proportion of successful responders with a reduction of 50% of VAS score at 12 and 24 weeks, the procedure time and pain and oxford knee score (OKS).VAS and OKS were recorded at 1, 4, 12, 24 weeks after intervention. Any complications were reported. ResultsMean VAS score in bipolar group was (p < 0.05) lower than monopolar group at 12 weeks [4.84 ± 0.62 Vs. 3.56 ± 0.71] and 24 weeks [5.44 ± 0.82 Vs. 3.96 ± 0.79]. The Proportion of successful responders with a reduction of at least 50% of VAS score were more in bipolar group than monopolar group at 12 weeks (80% Vs. 12%) and 24 weeks (44% Vs. 4%). Mean OKS score in bipolar group was (p < 0.05) lower than monopolar group at 12 weeks [26 ± 3 Vs. 34 ± 3] and 24 weeks [27 ± 3 Vs. 35 ± 3].The procedure time and pain were (p < 0.05) lower in monopolar than bipolar group. The complications were similar in both groups. ConclusionUSG bipolar RF ablation is more effective than monopolar RF ablation in controlling knee osteoarthritis pain as for the duration and severity of pain without fluoroscopic confirmation.

Clinical Efficacy of Interventional Chemotherapy Embolization Combined with Monopolar Radiofrequency Ablation on Patients with Liver Cancer.

Due to the greater prevalence of chronic hepatitis B infection, liver tumor is especially popular in China. In China, it is the 4th most prevalent tumor and the 3rd main reason for cancer fatalities. Hepatocellular carcinomas (HCCs) account for more than 91% of every liver tumor case, and chemotherapy and immunotherapy are the better therapy choices. It is a serious threat to the lives and health of Chinese citizens. Patients diagnosed with liver tumors have a bad prognosis. Surgical resection, liver transplantation, chemotherapeutic embolization, and radiofrequency ablation (RFA) are all choices for patients who are detected early. More effective therapies can result in a better prognosis. This paper analyzes the clinical efficiency of interventional transarterial chemoembolization (TACE) integrated with monopolar radiofrequency ablation (RFA) on patients with a liver tumor. Initially, the dataset is collected and the patients are treated with combined TACE and RFA. The computed tomography (CT) images are obtained using three-phase CT imaging. The images are segmented using adaptive U-Net-based segmentation. The clinical efficiency of the patients is evaluated using Robust Residual Convolutional Neural Network (RR-CNN) which is optimized using Firefly Particle Swarm Optimization (FPSO) algorithm. The performance of the system is analyzed using the MATLAB simulation tool. In performance analysis, the proposed method of RR-CNN is high when compared to the existing method of CNN, logistic regression using genetic algorithm and KNN in overall parameters are accuracy, sensitivity, F1-score, and specificity. These integrated treatments have a suggested greater response frequency, indicating a synergistic impact by combination treatment in the initial stages.

Percutaneous Endoluminal Radiofrequency Ablation of Occluded Biliary Metal Stent in Malignancy Using Monopolar Technique: A Feasibility Study.

To prove feasibility and safety of percutaneous endoluminal radiofrequency ablation (eRFA) using a monopolar approach in treatment of occluded biliary stent in malignancy. The study included 11 patients with occluded biliary metal stent that had been implanted due to malignant biliary obstruction. All underwent metal stent recanalization by percutaneous eRFA in monopolar setting. Sixteen eRFA procedures were performed under fluoroscopic guidance with an EndoHPB 8F radiofrequency ablation catheter. The effect of stent recanalization was assessed based upon change from pre- to post-procedural diameter of the patent lumen of the metal stent (Wilcoxon test), primary and secondary stent patency (compared by log-rank test), catheter-free period, and overall survival. Adverse events were evaluated according to Common Terminology Criteria for Adverse Events (CTCEA) 4.0. Recanalization of the metal stent by monopolar radiofrequency ablation was successful in all 11 patients. Diameter of the patent lumen of the stent significantly widened after the eRFA inside the stent (median 2 vs. 7mm, p = 0.003). Grade 1 complications were observed in one-third of procedures. Median stent patency after recanalization by eRFA was non-inferior to primary metal stent patency (154 vs. 161days, p = 0.27). Median catheter-free survival and overall survival after stent recanalization were 149 and 210days, respectively. Endoluminal radiofrequency ablation in monopolar setting was shown to be a feasible and safe method for recanalization of occluded biliary metal stents. Level 4, Case Series.

Radiofrequency Ablation in Cooled Monopolar or Conventional Bipolar Modality Yields More Beneficial Short-Term Clinical Outcomes Versus Other Treatments for Knee Osteoarthritis: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

To evaluate various radiofrequency ablation (RFA) treatments for knee osteoarthritis (OA) and determine the best modality, target, number of electrodes, and image guidance for improving knee pain and function. Electronic databases were searched for randomized controlled trials (RCTs) comparing the efficacy of RFA treatments for knee OA from inception up to September 30, 2021. The primary outcome was the visual analog scale (VAS), and the secondary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Bayesian network meta-analysis was performed to synthesize the mean difference (MD) and rank the comparative effectiveness of treatments. A total of 21 eligible RCTs (from 2011 to 2021, involving 1,818 patients) with 8 RFA treatments, 6 intra-articular injections, NSAIDS, exercise, and placebo were assessed. Conventional bipolar genicular nerve RFA (GNRFA) had the greatest net benefit on the VAS at 6 months (MD,-5.5; 95% confidence interval [CI],-4.3 to-6.7; SUCRA, .98). And cooled monopolar GNRFA had the greatest net benefit on the WOMAC at 6 months (MD,-33; 95% CI,-37 to-29; SUCRA, .99). In conventional and pulsed modalities, bipolar RFA was associated with a significant decrease in VAS and WOMAC than monopolar RFA. Combining pulsed intra-articular RFA and platelet-rich plasma injection had no additional positive effects on VAS or WOMAC at 3 months. RFA is effective in improving both knee pain and function in patients with OA, at least in the short term (6 months). Patients respond better to the cooled modality than the conventional and pulsed modalities. Bipolar is more effective than monopolar for improving pain and function in conventional and pulsed modalities. Fluoroscopy and ultrasound guidance showed no differences in improving pain and function. The effectiveness of RFA in cooled modality using bipolar or in combination with various intra-articular injections remains to be compared. II, systematic review and meta-analysis of Level I and II studies.

Percutaneous treatments of hepatocellular carcinoma: Improving efficacy, applicability and extending ablation criteria

AbstractThe main curative treatments of early hepatocellular carcinoma (HCC) are liver resection, liver transplantation and percutaneous ablation. Monopolar radiofrequency ablation (RFA) was the most widely used percutaneous treatment but has limitations in terms of applicability and efficacy. These limitations could be responsible for downgrading the treatment of early HCC not amenable to usual monopolar RFA, transplantation or resection and to a shift to palliative treatment. However, improvement in ablation techniques during the last 10 years including the development of microwave ablation, multibipolar RFA, irreversible electroporation but also new technical tricks for ablation allowed to optimize the efficacy and promote the wide application of percutaneous treatments in patients with early HCC. It helped also to explore the ability of percutaneous ablation to treat HCC outside current guidelines in order to ablate more lesions of larger sizes. In this review, we aim to describe how the improvement of ablation methods helps to maximize the number of patients treated for early HCC and to discuss if we could extend the usual ablation criteria in order to allocate more patients in a curative setting.

Outcome of No-Touch Radiofrequency Ablation for Small Hepatocellular Carcinoma: A Multicenter Clinical Trial.

Background Recently introduced no-touch radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) has the potential to improve local tumor control. Purpose To evaluate midterm clinical outcomes of monopolar no-touch RFA in single HCCs 2.5 cm or smaller. Materials and Methods In this multicenter clinical trial (ClinicalTrials.gov: NCT03375281), participants were evaluated for eligibility from November 2017 to January 2019. Patients with single HCCs 2.5 cm or smaller planning to be treated with no-touch RFA were enrolled. The rate of successful no-touch RFA, defined as performing RFA without violation of the tumor itself, was recorded. Multivariable logistic regression analysis was used to determine associated factors for failure of no-touch RFA. Development of major complication after no-touch RFA was also recorded. Cumulative incidence of local tumor progression (LTP) and recurrence-free survival were estimated by using the Kaplan-Meier method. Results A total of 140 participants (mean age, 62 years ± 9 [standard deviation]; 106 men) were evaluated. No-touch RFA was successfully performed in 128 participants (128 of 140; 91.4%), and conversion to tumor puncture RFA was undertaken in 12 participants because of the lack of a safe access route. By using either no-touch RFA or conversion to tumor puncture RFA, all participants achieved technical success of RFA, which was defined as complete coverage of target tumor by ablation zone. Insufficient peritumoral parenchyma (<5 mm width around more than half portion of tumor; odds ratio, 74; 95% CI: 18, 309; P < .001) was the only significant predictive factor for failure of the no-touch technique. Among the 140 participants, LTP developed in two participants, and the estimated 1- and 2-year cumulative incidence of LTP was 0.7% and 1.6%, respectively. The estimated 1- and 2-year recurrence-free survival was 82.8% and 74.1%, respectively. Conclusion No-touch radiofrequency ablation was an effective and safe treatment method for small hepatocellular carcinomas (≤2.5 cm), with 1.6% of cumulative incidence of local tumor progression at 2 years. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Soulen and García-Mónaco in this issue.

Review of Radiofrequency Ablation in Tonsillectomy.

The most common disease involving the tonsils among children and adults is chronic tonsillitis. There are different surgical techniques described in literature for the treatment of diseases involving the tonsils. Of these, the most routinely performed and the traditional method is conventional dissection tonsillectomy. The main disadvantage of this method is bleeding and postoperative pain. Radiofrequency ablation is found to overcome this limitation due to its mechanism of action. Both monopolar and bipolar radiofrequency ablation can be used in the surgical management. The effectiveness of monopolar radiofrequency has been proved in different fields of medicine. Hence new studies can be directed in comparing monopolar radiofrequency ablation with other techniques of tonsillectomy.

Radiofrequency Ablation: A Novel Treatment Option for Neck Recurrence in Medullary Thyroid Carcinoma

Abstract Background: Medullary thyroid carcinoma (MTC) is an aggressive cancer with cervical lymph node metastases typically found at presentation. The recurrence rate after resection is high (~ 50%)(1), and patients often need multiple surgeries. Radiofrequency ablation (RFA) has been used in treatment of recurrent thyroid cancer when surgery is contraindicated or declined by patients in both Asia and Europe (2). We present the first case of an MTC recurrence treated successfully with RFA in North America. Clinical Case: A 43-year-old female with sporadic metastatic MTC, status post total thyroidectomy and multiple neck surgeries, presented with elevated calcitonin level of 630 pg/mL (normal: &amp;lt; 10 pg/mL). Neck ultrasound showed left tracheoesophageal groove mass, measuring 12 mm X 12 mm X 17 mm, consistent with metastatic MTC on cytopathology with calcitonin washout of 16590 pg/mL (normal: &amp;lt; 10 pg/mL). She had no dysphagia, shortness of breath or hoarseness of voice. Computed tomography (CT) scan of chest confirmed presence of mass, in proximity with left recurrent laryngeal nerve. Serial imaging showed rapid enlargement, with concern for impending aerodigestive tract invasion. Surgical intervention had a high risk of vocal cord paralysis due to the lesion’s location. A multidisciplinary tumor board agreed that thermal ablation aimed at shrinking the mass, as a bridge to systemic therapy, would be the best option. RFA was performed as an outpatient with conscious sedation, after informed consent and observing standard aseptic techniques. Under continuous ultrasound guidance, D5W was injected into left tracheoesophageal groove behind the mass and a continuous infusion of D5W at 15 mL/hr was maintained to protect the nerve from thermal injury. Using a trans-isthmic approach, an 18 G monopolar RFA probe with 5 mm active tip was advanced into the malignant mass and ablation was performed with 35 W power until the entire mass was hyperechoic. Vocal response was monitored throughout the procedure and voice remained normal after RFA. A neck ultrasound at her 6 months follow-up showed ablated lesion measuring 7 mm X 11 mm X 10 mm, representing a 68.6% reduction in volume. Repeat CT scan thorax showed disappearance of mass in left neck region. Conclusion: RFA is a minimally invasive and effective treatment for recurrent cervical MTC lesions, and a viable alternative to surgery, as shown in our case. Future studies should focus on long term follow-up and comparison with surgery with regards to safety and efficacy.

Switching monopolar radiofrequency ablation improves long-term outcomes of medium-sized hepatocellular carcinoma.

Radiofrequency ablation (RFA) of medium-sized (3-5 cm) hepatocellular carcinoma (HCC) is suboptimal. Switching monopolar RFA (SW-RFA) enlarges the ablative volume to better cover larger tumors. This study aims to compare the long-term outcomes of medium-sized HCC treated by either SW-RFA or single-monopolar RFA (S-RFA). We retrospectively reviewed 139 cases (147 medium-size HCC) between 2008 and 2014. Under propensity score matching, a total of 43 paired patients with medium-size HCC and balanced clinical variables treated by either SW-RFA or S-RFA were selected for comparison. SW-RFA showed a higher rate of achieving an adequate safety margin (p = 0.002). After a mean follow-up period of 40.4 months, SW-RFA produced significantly lower global RFA failure rates (p < 0.001) and better overall survival (p = 0.005) compared to S-RFA. SW-RFA was independently associated with a decreased risk of global RFA failure (hazard ratio [HR]: 0.136, 95% confidence interval [CI]: 0.030-0.607, p = 0.009) and improved overall survival (HR: 0.337, 95% CI: 0.152-0.747, p = 0.007). By last follow-up, the SW-RFA group maintained a superior tumor-free rate (p = 0.010) and fewer progressions to Barcelona Clinic Liver Cancer stage C (p = 0.011). Major complication rates were comparable in both groups (SW-RFA: 2.3% vs. S-RFA: 4.7%, p = 1.000). The switching multi-monopolar ablation technique could be beneficial for patients with medium-sized HCCs given sustained control of larger tumors with better overall survival. • Switching monopolar ablation could provide a sustained local tumor control and better overall survival than single-monopolar ablation for the medium-sized hepatocellular carcinoma. • Compared to single-monopolar ablation, switching monopolar ablation could create a larger homogeneous coagulation volume by using a shorter total ablation time to achieve a higher rate of adequate safety margin for a medium-sized HCC. • Patients with medium-sized HCC can be maintained at a higher rate of tumor-free status and at a lower risk of progression into BCLC stage C in the follow-up period after ablation by switching monopolar than by single-monopolar ablation.