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Sample records for bipolar radiofrequency ablation

  1. CT-guided Bipolar and Multipolar Radiofrequency Ablation (RF Ablation) of Renal Cell Carcinoma: Specific Technical Aspects and Clinical Results

    SciTech Connect

    Sommer, C. M.; Lemm, G.; Hohenstein, E.; Bellemann, N.; Stampfl, U.; Goezen, A. S.; Rassweiler, J.; Kauczor, H. U.; Radeleff, B. A.; Pereira, P. L.

    2013-06-15

    Purpose. This study was designed to evaluate the clinical efficacy of CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma (RCC) and to analyze specific technical aspects between both technologies. Methods. We included 22 consecutive patients (3 women; age 74.2 {+-} 8.6 years) after 28 CT-guided bipolar or multipolar RF ablations of 28 RCCs (diameter 2.5 {+-} 0.8 cm). Procedures were performed with a commercially available RF system (Celon AG Olympus, Berlin, Germany). Technical aspects of RF ablation procedures (ablation mode [bipolar or multipolar], number of applicators and ablation cycles, overall ablation time and deployed energy, and technical success rate) were analyzed. Clinical results (local recurrence-free survival and local tumor control rate, renal function [glomerular filtration rate (GFR)]) and complication rates were evaluated. Results. Bipolar RF ablation was performed in 12 procedures and multipolar RF ablation in 16 procedures (2 applicators in 14 procedures and 3 applicators in 2 procedures). One ablation cycle was performed in 15 procedures and two ablation cycles in 13 procedures. Overall ablation time and deployed energy were 35.0 {+-} 13.6 min and 43.7 {+-} 17.9 kJ. Technical success rate was 100 %. Major and minor complication rates were 4 and 14 %. At an imaging follow-up of 15.2 {+-} 8.8 months, local recurrence-free survival was 14.4 {+-} 8.8 months and local tumor control rate was 93 %. GFR did not deteriorate after RF ablation (50.8 {+-} 16.6 ml/min/1.73 m{sup 2} before RF ablation vs. 47.2 {+-} 11.9 ml/min/1.73 m{sup 2} after RF ablation; not significant). Conclusions. CT-guided bipolar and multipolar RF ablation of RCC has a high rate of clinical success and low complication rates. At short-term follow-up, clinical efficacy is high without deterioration of the renal function.

  2. Direct Current Combined With Bipolar Radiofrequency Ablation: An Ex Vivo Feasibility Study

    SciTech Connect

    Tanaka, Toshihiro Penzkofer, Tobias; Isfort, Peter; Bruners, Philipp; Disselhorst-Klug, Catherine; Junker, Elmar; Kichikawa, Kimihiko; Schmitz-Rode, Thomas; Mahnken, Andreas H.

    2011-06-15

    The combination of radiofrequency ablation (RFA) with direct current (DC) is a promising strategy to improve the efficiency of RFA. However, DC-enhanced monopolar RFA is limited by electrolytic injury at the positive-electrode site. The aim of this study was to investigate the feasibility of the DC-enhanced bipolar RFA. To obviate the need for the subcutaneous positive electrode, the DC circuit was combined with a commercially available bipolar RFA system, in which both poles of the DC circuit are connected to a single RF probe. DC was applied for 15 min and followed by RFA in bovine livers using the following various DC currents: (1) no DC (control), (2) 3V continued until the end of RFA, (3) 5V continued until the end of RFA, (4) 10V continued until the end of RFA, (5) 5V continued in the circuit with reversed pole, (6) 3V stopped after initiation of RFA, and (7) 5V stopped. Coagulation volume, temperatures at a distance of 5, 10, and 15 mm from the RF probe, mean amperage, ablation duration, applied energy, minimum impedance, and degree of tissue charring were assessed and compared (analysis of variance, Student-Newman-Keuls test). All combined DC and RFA groups did increase coagulation volume. The 10V continued group showed significantly lower applied energy, shortest ablation duration, highest minimum impedance, and highest degree of charring with the lowest coagulation volume (p < 0.05). DC-enhanced bipolar RFA with both poles of the DC circuit on a single probe appears to be ineffective.

  3. Heat sink effect on tumor ablation characteristics as observed in monopolar radiofrequency, bipolar radiofrequency, and microwave, using ex vivo calf liver model.

    PubMed

    Pillai, Krishna; Akhter, Javid; Chua, Terence C; Shehata, Mena; Alzahrani, Nayef; Al-Alem, Issan; Morris, David L

    2015-03-01

    Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink. PMID:25738477

  4. Heat Sink Effect on Tumor Ablation Characteristics as Observed in Monopolar Radiofrequency, Bipolar Radiofrequency, and Microwave, Using Ex Vivo Calf Liver Model

    PubMed Central

    Pillai, Krishna; Akhter, Javid; Chua, Terence C.; Shehata, Mena; Alzahrani, Nayef; Al-Alem, Issan; Morris, David L.

    2015-01-01

    Abstract Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices. With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored. With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres. Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected. Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5. MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink. PMID:25738477

  5. Efficacy of a novel bipolar radiofrequency ablation device on the beating heart for atrial fibrillation ablation: A chronic porcine study

    PubMed Central

    Voeller, Rochus K.; Zierer, Andreas; Lall, Shelly C.; Sakamoto, Shun-ichiro; Schuessler, Richard B.; Damiano, Ralph J.

    2015-01-01

    Background Over the recent years, a variety of energy sources have been used to replace the traditional incisions of the Cox-Maze procedure for the surgical treatment of atrial fibrillation. This study evaluated the safety and efficacy of a new bipolar radiofrequency ablation device for atrial ablation in a chronic porcine model. Methods Six pigs underwent a Cox-Maze IV procedure on a beating heart off cardiopulmonary bypass using the Atricure Isolator II™ bipolar ablation device. In addition, 6 pigs underwent median sternotomy and pericardiotomy alone to serve as a control group. All animals were survived for 30 days. Each pig underwent induction of atrial fibrillation, and was then sacrificed to remove the heart en bloc for histological assessment. MRI scan were also obtained preoperatively and postoperatively to assess atrial and ventricular function, pulmonary vein anatomy, valve function, and coronary artery patency. Results All animals survived the operation. Electrical isolation of the left atrial appendage and the pulmonary veins was documented by pacing acutely and at 30 days in all animals. No animal that underwent the Cox-Maze IV procedure was able to be induced into atrial fibrillation at 30 days postoperatively, compared to all the sham animals. All 257 ablations examined were discrete, linear and transmural, with a mean lesion width of 2.2±1.1 mm and a mean lesion depth of 5.3±3.0 mm. Conclusions The Atricure Isolator II™ was able to create reliable chronic transmural lesions of the modified Cox-Maze procedure on a beating heart without cardiopulmonary bypass 100% of the time. There were no discernible effects on ventricular or valvular function. PMID:20122702

  6. Bipolar radiofrequency ablation of benign thyroid nodules using a multiple overlapping shot technique in a 3-month follow-up.

    PubMed

    Kohlhase, Konstantin David; Korkusuz, Yücel; Gröner, Daniel; Erbelding, Christian; Happel, Christian; Luboldt, Wolfgang; Grünwald, Frank

    2016-08-01

    Purpose The aim of this study was to evaluate the decrease of benign thyroid nodules after bipolar radiofrequency ablation (RFA) in a 3-month follow-up using a multiple overlapping shot technique ('MOST'). Methods A total of 18 patients with 20 symptomatic benign thyroid nodules (17 cold nodules, 3 hyperfunctioning nodules) were treated in one single session by bipolar RFA. Bipolar ablation was performed using MOST. The nodule volumes were measured prior to ablation and 3 months after the procedure using ultrasound. The population consisted of either solid (>80% solid tissue within the volume of interest), complex, or cystic nodules (<20% solid tissue within the volume of interest). Results Bipolar RFA resulted in a highly significant (p < 0.0001) decrease of nodule volume (ΔV), median 5.3 mL (range 0.13-43.1 mL), corresponding to a relative reduction in mean of 56 ± 17.9%. Median initial volume was 8 mL (range 0.48-62 mL); 3 months after ablation a median volume of 2.3 mL (range 0.3-32 mL) was measured. Nodule growth ≥50% occurred in 70% (14 nodules). At the follow-up no complications such as infections, persisting pain, nerve injuries or immunogen stimulation occurred. Patients with cold nodules (15) remained euthyroid, with hyperfunctioning nodules either euthyroid (2) or latent hypofunctional (1). Conclusion The use of bipolar RFA is an effective, safe and suitable thermoablative technique to treat benign thyroid nodules. Combined with the multiple overlapping shot technique it allows sufficient ablation. PMID:27126512

  7. Analysis of Bipolar Radiofrequency Ablation in Treatment of Atrial Fibrillation Associated with Rheumatic Heart Disease

    PubMed Central

    Li, Yang; Wu, Zhong

    2016-01-01

    Background Among patients with rheumatic heart disease (RHD), 45% to 60% present with atrial fibrillation (AF), which is associated with increased rates of thromboembolism, heart failure, and even death. The bipolar radiofrequency ablation (BRFA) combining with mitral valve procedure has been adopted in patients of AF associated with RHD, but evaluations about its effectiveness are still limited. Methods A total of 87 patients with RHD and long persistent AF who had accepted mitral valve replacement concomitant with BRFA were studied. Clinical data were collected to analyze the midterm results of BRFA and evaluate its efficiency. Univariate and multivariate analyses were used to identify the independent factors associated with late AF recurrence. Results Sixty-six (75.9%) patients maintained sinus rhythm after a mean follow-up of 13.4 ± 5.2 months. Late AF recurrence had been detected in 21 (24.1%) patients, 11 (12.6%) patients were confirmed to be AF, 8 (9.2%) patients were atrial flutter and 2 (2.3%) patients were junctional rhythm. In Multivariate logistic regression analysis, body mass index (BMI) (OR = 1.756, 95% CI = 1.289–2.391, p = 0.000) and early AF recurrence (OR = 5.479, 95% CI = 1.189–25.254, p = 0.029) were independent predictors of late AF recurrence. In addition, left ventricular ejection fraction (LVEF) and New York Heart Association class showed a greater improvement in patients who maintained sinus rhythm than those who experienced late AF recurrence. Conclusion BRFA is an effective technique for the treatment of long persistent AF associated with RHD during mitral valve replacement. The BMI and early AF recurrence are independent predictors for late AF recurrence. Patients with long-term restoration of sinus rhythm experienced a greater improvement of left ventricular function after BRFA. PMID:26960188

  8. Performance of a Novel Bipolar/Monopolar Radiofrequency Ablation Device on the Beating Heart in an Acute Porcine Model

    PubMed Central

    Saint, Lindsey L.; Lawrance, Christopher P.; Okada, Shoichi; Kazui, Toshinobu; Robertson, Jason O.; Schuessler, Richard B.; Damiano, Ralph J.

    2013-01-01

    SUMMARY Objective Although the advent of ablation technology has simplified and shortened surgery for atrial fibrillation, only bipolar clamps have reliably been able to create transmural lesions on the beating heart. Currently there are no devices capable of reproducibly creating the long linear lesions in the right and left atria needed to perform a Cox-Maze procedure. This study evaluated the performance of a novel suction-assisted radiofrequency device that uses both bipolar and monopolar energy to create lesions from an epicardial approach on the beating heart. Methods Six domestic pigs underwent median sternotomy. A dual bipolar/monopolar radiofrequency ablation device was used to create epicardial linear lesions on the superior and inferior vena cavae, right and left atrial free walls, and right and left atrial appendages. The heart was stained with 2,3,5-triphenyl-tetrazolium chloride and each lesion was cross-sectioned at 5mm intervals. Lesion depth and transmurality were determined. Results Transmurality was documented in 94% of all cross-sections, and 68% of all ablation lines were transmural along their entire length. Tissue thickness was not different between transmural and non-transmural cross-sections (3.1 ± 1.3 and 3.4 ± 2.1, p=0.57, respectively), nor was the anatomic location on the heart (p=0.45 for the distribution). Of the cross-sections located at the end of the ablation line, 11% (8/75) were found to be non-transmural, whereas only 4% (8/195) of cross-sections located within the line of ablation were found to be non-transmural (p=0.04). Logistic regression analysis demonstrated that failure of the device to create transmural lesions was associated with low body temperature (p=0.006), but not with cardiac output (p=0.54). Conclusions This novel device was able to consistently create transmural epicardial lesions on the beating heart, regardless of anatomic location, cardiac output or tissue thickness. The performance of this device was

  9. Radiofrequency Ablation of Cancer

    PubMed Central

    Friedman, Marc; Mikityansky, Igor; Kam, Anthony; Libutti, Steven K.; Walther, McClellan M.; Neeman, Ziv; Locklin, Julia K.; Wood, Bradford J.

    2008-01-01

    Radiofrequency ablation (RFA) has been used for over 18 years for treatment of nerve-related chronic pain and cardiac arrhythmias. In the last 10 years, technical developments have increased ablation volumes in a controllable, versatile, and relatively inexpensive manner. The host of clinical applications for RFA have similarly expanded. Current RFA equipment, techniques, applications, results, complications, and research avenues for local tumor ablation are summarized. PMID:15383844

  10. Radiofrequency Ablation of Cancer

    SciTech Connect

    Friedman, Marc; Mikityansky, Igor; Kam, Anthony; Libutti, Steven K.; Walther, McClellan M.; Neeman, Ziv; Locklin, Julia K.; Wood, Bradford J.

    2004-09-15

    Radiofrequency ablation (RFA) has been used for over 18 years for treatment of nerve-related chronic pain and cardiac arrhythmias. In the last 10 years, technical developments have increased ablation volumes in a controllable, versatile, and relatively inexpensive manner. The host of clinical applications for RFA have similarly expanded. Current RFA equipment, techniques, applications, results, complications, and research avenues for local tumor ablation are summarized.

  11. Evolving technology in bipolar perfused radiofrequency ablation: assessment of efficacy, predictability and safety in a pig liver model.

    PubMed

    Burdío, Fernando; Navarro, Ana; Sousa, Ramón; Burdío, José M; Güemes, Antonio; Gonzalez, Ana; Cruz, Ignacio; Castiella, Tomás; Lozano, Ricardo; Berjano, Enrique; Figueras, Joan; de Gregorio, Miguel A

    2006-08-01

    Bipolar radiofrequency (RF) ablation, especially with perfusion of saline, has been shown to increase volume over monopolar conventional methods. The aims of this study are to study whether this method is linked to too flattened thermal lesions and premature rise of impedance and to elucidate some safety concerns. Eighteen RF ablations were performed using a 1.8-mm-diameter bipolar applicator in the liver of nine healthy pigs through laparotomy with or without temporary vascular occlusion [the Pringle maneuver (PGM)]: group A (n=9), without PGM; group B (n=9), with PGM. Hypertonic saline solutions (3% and 20 %) were injected through the applicator at a rate of 400 ml/h during the procedure. The pigs were followed up and they were euthanased on the 15th day. Impedance, current, power output, energy output, temperatures, diameters of thermal lesion, volume, sphericity ratio of thermal lesion were correlated among groups. Impedance at the end of the procedure (50.00 Omega+/-28.39 and 52.88 Omega+/-26.77, for groups A and B, respectively) was very similar to the starting impedance (50 Omega). In a median of 1 (range, 0-6) time per RF ablation procedure a reduction of 30 W from the selected power supply was observed during the RF ablation procedure linked to a slight increase of impedance. Volume and short diameter of thermal lesion were 21.28 cm3+/-11.78 and 2.85 cm+/-0.87 for group A, 87.51 cm3+/-25.20 and 4.31 cm+/-0.65 for group B. Continuous thermal between both electrodes were described with a global sphericity ratio of 1.91. One major complication (thermal injury to the stomach) was encountered in a case of cross-sectional necrosis of the targeted liver and attributed to heat diffusion after the procedure. This method has been shown to determine: (1) the relative control of impedance during the procedure; (2) ovoid and relatively large thermal lesions with less dependence upon closest vessels. PMID:16541228

  12. Radiofrequency Thermal Ablation versus Bipolar Electrocautery for the Treatment of Inferior Turbinate Hypertrophy: Comparison of Efficacy and Postoperative Morbidity

    PubMed Central

    Uluyol, Sinan; Karakaya, Nermin Erdas; Gur, Mehmet Hafit; Kilicaslan, Saffet; Kantarcioglu, Esin Ozlem; Yagiz, Ozlem; Arslan, Ilker Burak

    2015-01-01

    Introduction Numerous surgical methods are used to treat nasal obstruction due to inferior turbinate hypertrophy. The primary goal of the therapy is to maximize the nasal airway for as extended a period of time as possible while minimizing therapeutic complications. Objectives The aim of this study was to assess the effects of radiofrequency thermal ablation (RFTA) and bipolar electrocautery (BEC) on the removal of nasal obstruction in patients with inferior turbinate hypertrophy and on nasal mucociliary clearance (MCC). Patients in both groups were also evaluated in terms of postoperative morbidity. Methods We compared the outcomes of two groups of patients: those treated with RFTA (n = 23) and those who underwent BEC (n = 20). Nasal obstruction was graded using a visual analog scale (VAS) and MCC was measured using a saccharin clearance test. Both measurements were performed before and 2 months after treatment. Results Pre- and postoperative VAS scores showed significant improvement for both groups. However, MCC results did not significantly differ between two groups. Neither edema nor crust formation persisted for more than 1 week in any patients. Conclusion Submucosal cauterization with preservation of the nasal mucosa and periosteum is as effective and safe as RFTA and should be considered when planning inferior turbinate interventions. PMID:26722337

  13. A simulation study to compare the phase-shift angle radiofrequency ablation mode with bipolar and unipolar modes in creating linear lesions for atrial fibrillation ablation.

    PubMed

    Yan, Shengjie; Wu, Xiaomei; Wang, Weiqi

    2016-05-01

    Purpose In pulmonary veins (PVs) isolation (PVI), radiofrequency (RF) energy is often used to create a linear lesion for blocking the accessory conduction pathways around PVs. By using transient finite element analysis, this study compared the effectiveness of phase-shift mode (PsM) ablation with bipolar mode (BiM) and unipolar mode (UiM) in creating a continuous lesion and lesion depth in a 5-mm thick atrial wall. Materials and methods Computer models were developed to study the temperature distributions and lesion dimensions in atrial walls created through PsM, BiM, and UiM. Four phase-shift angles - 45°, 90°, 135°, and 180° - were considered in PsM ablation (hereafter, PsM-45°, PsM-90°, PsM-135°, and PsM-180°, respectively). Results At 60 s/30 V peak value of RF voltage, UiM and PsM-45° did not create an effective lesion, whereas BiM created a lesion of maximum depth and width approximately 1.01 and 1.62 mm, respectively. PsM-135° and PsM-180° not only created transmural lesions in 5-mm thick atrial walls but also created continuous lesions between electrodes spaced 4 mm apart; similarly, PsM-90° created a continuous lesion with a maximum depth and width of nearly 4.09 and 6.12 mm. Conclusions Compared with UiM and BiM, PsM-90°, PsM-135° and PsM-180° created continuous and larger lesions in a single ablation procedure and at 60 s/30 V peak value of RF voltage. Therefore, the proposed PsM ablation method is suitable for PVI and linear isolation at the left atrial roof for treating atrial fibrillation. PMID:26915712

  14. Multicenter Experience with Nonischemic Multiport Laparoscopic and Laparoendoscopic Single-Site Partial Nephrectomy Utilizing Bipolar Radiofrequency Ablation Coagulator

    PubMed Central

    Bazzi, Wassim M.; Allaf, Mohamad E.; Berkowitz, Jared; Atalah, Hany N.; Parekattil, Sijo; Derweesh, Ithaar H.

    2011-01-01

    Objective. To investigate feasibility of multiport and laparoendoscopic single-site (LESS) nonischemic laparoscopic partial nephrectomy (NI-LPN) utilizing bipolar radiofrequency coagulator. Methods. Multicenter retrospective review of 60 patients (46 multiport/14 LESS) undergoing NI-LPN between 4/2006 and 9/2009. Multiport and LESS NI-LPN utilized Habib 4X bipolar radiofrequency coagulator to form a hemostatic zone followed by nonischemic tumor excision and renorrhaphy. Demographics, tumor/perioperative characteristics, and outcomes were analyzed. Results. 59/60 (98.3%) successfully underwent NI-LPN. Mean tumor size was 2.35 cm. Mean operative time was 160.0 minutes. Mean estimated blood loss was 131.4 mL. Preoperative/postoperative creatinine (mg/dL) was 1.02/1.07 (P = .471). All had negative margins. 12 (20%) patients developed complications. 3 (5%) developed urine leaks. No differences between multiport and LESS-PN were noted as regards demographics, tumor size, outcomes, and complications. Conclusion. Initial experience demonstrates that nonischemic multiport and LESS-PN is safe and efficacious, with excellent short-term preservation of renal function. Long-term data are needed to confirm oncological efficacy. PMID:21747654

  15. Bipolar radiofrequency ablation for liver tumors: comparison of contrast-enhanced ultrasound with contrast-enhanced MRI/CT in the posttreatment imaging evaluation

    PubMed Central

    Bo, Xiao-Wan; Xu, Hui-Xiong; Sun, Li-Ping; Zheng, Shu-Guang; Guo, Le-Hang; Lu, Feng; Wu, Jian; Xu, Xiao-Hong

    2014-01-01

    Objective: The aim of the study was to assess the role of contrast-enhanced ultrasound (CEUS) in treatment response evaluation after percutaneous bipolar radiofrequency ablation (BRFA) for liver tumors. Methods: From May 2012 to May 2014, 39 patients with 73 tumors were treated by BRFA. One month after the treatment, CEUS and CEMRI/CECT were conducted to evaluate the treatment response. The results of CEUS were compared with CEMRI/CECT. Results: Of the 73 tumors ablated, eight (11.0%) were found to have residual viable tumor tissue and 65 (89.0%) were successfully ablated based on CEMRI/CECT within 1-month after ablation. CEUS detected seven of the eight residual tumors and 63 of 65 completely ablated tumors. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CEUS were 87.5% (7/8), 96.9% (63/65), 77.8% (7/9), 98.4% (63/64) and 95.9% (70/73), respectively. The complete ablation (CR) rates for the tumors ≤3.0 cm, 3.1-5.0 cm, and >5.0 cm were 96.6% (58/60), 63.6% (7/11), and 0% (0/2), respectively (P<0.001). CR rates were 94.7% (36/38) for primary liver tumors and 82.9% (29/35) for metastatic liver tumors (P=0.212), and were 97.4% (38/39) for the tumors with curative treatment intention and 79.4% (27/34) for those with palliative treatment intention (P=0.037). Major complication was not encountered in this series. Conclusions: BRFA is an effective technique of percutaneous ablation for liver tumors and CEUS can be used to assess its therapeutic effect accurately. PMID:25337258

  16. Radiofrequency Ablation of Metastatic Pheochromocytoma

    PubMed Central

    Venkatesan, Aradhana M.; Locklin, Julia; Lai, Edwin W.; Adams, Karen T.; Fojo, Antonio Tito; Pacak, Karel; Wood, Bradford J.

    2013-01-01

    In the present report on the preliminary safety and effectiveness of radiofrequency (RF) ablation for pheochromocytoma metastases, seven metastases were treated in six patients (mean size, 3.4 cm; range, 2.2–6 cm). α- and β-adrenergic and catecholamine synthesis inhibition and intraprocedural anesthesia monitoring were used. Safety was assessed by recording ablation-related complications. Complete ablation was defined as a lack of enhancement within the ablation zone on follow-up computed tomography. No serious adverse sequelae were observed. Complete ablation was achieved in six of seven metastases (mean follow-up, 12.3 months; range, 2.5–28 months). In conclusion, RF ablation may be safely performed for metastatic pheochromocytoma given careful attention to peri-procedural management. PMID:19875067

  17. Radiofrequency catheter ablation of accessory pathways in infants.

    PubMed Central

    Benito, F.; Sánchez, C.

    1997-01-01

    OBJECTIVE: To evaluate the indications, results and complications of radiofrequency catheter ablation in small infants with supraventricular tachycardia due to an accessory atrioventricular pathway. METHODS: Five infants less than 9 months old underwent radiofrequency catheter ablation of accessory pathways. Ablation was done for medically refractory tachyarrhythmia associated with aborted sudden death in two patients, left ventricular dysfunction in one, failure of antiarrhythmic drugs in one, and planned cardiac surgery in one. All five patients underwent a single successful procedure. Three left free wall pathways were ablated by transseptal approach, a right posteroseptal pathway was ablated from the inferior vena cava, and a left posteroseptal pathway was approached from the inferior vena cava into the coronary sinus. A deflectable 5F bipolar electrode catheter with a 3 mm tip was used. RESULTS: A sudden increment in impedance indicative of coagulum formation was observed in two procedures. One patient developed a transient ischaemic complication after ablation of a left lateral accessory pathway by transseptal approach. This patient had mild pericardial effusion after the procedure. Moderate pericardial effusion was also noted in another patient. After a mean follow up of 18.4 months all patients are symptom free without treatment. CONCLUSIONS: Radiofrequency catheter ablation can be performed successfully in infants. Temperature monitoring in 5F ablation catheters would be desirable to prevent the development of coagulum. Echocardiography must be performed after the ablation procedure to investigate pericardial effusion. Images PMID:9326990

  18. Esophageal papilloma: Flexible endoscopic ablation by radiofrequency

    PubMed Central

    del Genio, Gianmattia; del Genio, Federica; Schettino, Pietro; Limongelli, Paolo; Tolone, Salvatore; Brusciano, Luigi; Avellino, Manuela; Vitiello, Chiara; Docimo, Giovanni; Pezzullo, Angelo; Docimo, Ludovico

    2015-01-01

    Squamous papilloma of the esophagus is a rare benign lesion of the esophagus. Radiofrequency ablation is an established endoscopic technique for the eradication of Barrett esophagus. No cases of endoscopic ablation of esophageal papilloma by radiofrequency ablation (RFA) have been reported. We report a case of esophageal papilloma successfully treated with a single session of radiofrequency ablation. Endoscopic ablation of the lesion was achieved by radiofrequency using a new catheter inserted through the working channel of endoscope. The esophageal ablated tissue was removed by a specifically designed cup. Complete ablation was confirmed at 3 mo by endoscopy with biopsies. This case supports feasibility and safety of as a new potential indication for BarrxTM RFA in patients with esophageal papilloma. PMID:25789102

  19. Percutaneous Tumor Ablation with Radiofrequency

    PubMed Central

    Wood, Bradford J.; Ramkaransingh, Jeffrey R.; Fojo, Tito; Walther, McClellan M.; Libutti, Stephen K.

    2008-01-01

    BACKGROUND Radiofrequency thermal ablation (RFA) is a new minimally invasive treatment for localized cancer. Minimally invasive surgical options require less resources, time, recovery, and cost, and often offer reduced morbidity and mortality, compared with more invasive methods. To be useful, image-guided, minimally invasive, local treatments will have to meet those expectations without sacrificing efficacy. METHODS Image-guided, local cancer treatment relies on the assumption that local disease control may improve survival. Recent developments in ablative techniques are being applied to patients with inoperable, small, or solitary liver tumors, recurrent metachronous hereditary renal cell carcinoma, and neoplasms in the bone, lung, breast, and adrenal gland. RESULTS Recent refinements in ablation technology enable large tumor volumes to be treated with image-guided needle placement, either percutaneously, laparoscopically, or with open surgery. Local disease control potentially could result in improved survival, or enhanced operability. CONCLUSIONS Consensus indications in oncology are ill-defined, despite widespread proliferation of the technology. A brief review is presented of the current status of image-guided tumor ablation therapy. More rigorous scientific review, long-term follow-up, and randomized prospective trials are needed to help define the role of RFA in oncology. PMID:11900230

  20. Radiofrequency Ablation of Liver Tumors

    MedlinePlus

    ... Other equipment such as needle electrodes, an electrical generator and grounding pads may also be used. Radiofrequency ... retractable electrodes that extend when needed. The radiofrequency generator produces electrical currents in the range of radiofrequency ...

  1. Irrigated tip catheters for radiofrequency ablation in ventricular tachycardia.

    PubMed

    Müssigbrodt, Andreas; Grothoff, Matthias; Dinov, Borislav; Kosiuk, Jedrzej; Richter, Sergio; Sommer, Philipp; Breithardt, Ole A; Rolf, Sascha; Bollmann, Andreas; Arya, Arash; Hindricks, Gerhard

    2015-01-01

    Radiofrequency (RF) ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT) ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy. PMID:25705659

  2. Irrigated Tip Catheters for Radiofrequency Ablation in Ventricular Tachycardia

    PubMed Central

    Grothoff, Matthias; Dinov, Borislav; Kosiuk, Jedrzej; Richter, Sergio; Sommer, Philipp; Breithardt, Ole A.; Bollmann, Andreas; Arya, Arash; Hindricks, Gerhard

    2015-01-01

    Radiofrequency (RF) ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT) ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy. PMID:25705659

  3. Radiofrequency ablation for hepatocellular carcinoma.

    PubMed

    Nishikawa, Hiroki; Kimura, Toru; Kita, Ryuichi; Osaki, Yukio

    2013-09-01

    Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related mortality worldwide. Unfortunately, only 20% of HCC patients are amenable to curative therapy (liver transplantation or surgical resection). Locoregional therapies such as radiofrequency ablation (RFA), percutaneous ethanol injection, microwave coagulation therapy, and transcatheter arterial chemoembolisation play a key role in the management of HCC. The choice of the treatment modality depends on the size of the tumour, tumour location, anatomic considerations and the number of tumours present and liver function. RFA therapy for HCC can be performed safely using a percutaneous, laparoscopic, or an open approach, even in patients with poor functional reserve. Since the introduction of RFA, several randomised controlled trials and non-randomised studies comparing RFA and other therapies for HCC have been conducted. In addition, in the last decade there have been technical advances in RFA therapy for HCC, resulting in significant improvement in the prognosis of HCC patients treated with this modality. In this review, we primarily focus on percutaneous RFA therapy for HCC and refer to current knowledge and future perspectives for this therapy. We also discuss new emerging ablation techniques. PMID:23937321

  4. Radiofrequency Ablation to Prevent Sudden Cardiac Death

    PubMed Central

    Atoui, Moustapha; Gunda, Sampath; Lakkireddy, Dhanunjaya; Mahapatra, Srijoy

    2015-01-01

    Radiofrequency ablation may prevent or treat atrial and ventricular arrhythmias. Since some of these arrhythmias are associated with sudden cardiac death, it has been hypothesized that ablation may prevent sudden death in certain cases. We performed a literature search to better understand under which circumstances ablation may prevent sudden death and found little randomized data demonstrating the long-term effects of ablation. Current literature shows that ablation clearly prevents symptoms of arrhythmia and may reduce the incidence of sudden cardiac death in select patients, although data does not indicate improved mortality. Ongoing clinical trials are needed to better define the role of ablation in preventing sudden cardiac death. PMID:26306130

  5. Radiofrequency Ablation of Lung Tumors

    MedlinePlus

    ... computed tomography (CT) imaging, needle electrodes , an electrical generator and grounding pads are used. There are two ... retractable electrodes that extend when needed. The radiofrequency generator produces electrical currents in the range of radiofrequency ...

  6. Radiofrequency ablation technique eradicating palpebral margin neoplasm

    PubMed Central

    Jiang, Tian-Yu; Wang, Xing-Lin; Suo, Wei; He, Qing-Hua; Xiao, Hong-Yu

    2011-01-01

    AIM To report the study on radiofrequency ablation technique for eradication of palpebral margin neoplasm and its clinical effects. METHODS One hundred and six cases with the palpebral margin neoplasm were performed surgical removal with radiofrequency ablation technique. The 1-2 months postoperative follow-up was investigated and the lost cases were excluded from statistics. The continuing follow-up lasted about 6-16months. RESULTS One hundred cases underwent one treatment and 6 cases underwent two treatments. Six cases were missed. All the cases followed up healed well without pigmentation or scar left, nor eyelash loss or palpebral margin deformation. No case was recurrent. CONCLUSION Radiofrequency ablation has significant efficiency in eradicating the palpebral margin neoplasm. PMID:22553639

  7. Microwave Ablation Compared with Radiofrequency Ablation for Breast Tissue in an Ex Vivo Bovine Udder Model

    SciTech Connect

    Tanaka, Toshihiro; Westphal, Saskia; Isfort, Peter; Braunschweig, Till; Penzkofer, Tobias Bruners, Philipp; Kichikawa, Kimihiko; Schmitz-Rode, Thomas Mahnken, Andreas H.

    2012-08-15

    Purpose: To compare the effectiveness of microwave (MW) ablation with radiofrequency (RF) ablation for treating breast tissue in a nonperfused ex vivo model of healthy bovine udder tissue. Materials and Methods: MW ablations were performed at power outputs of 25W, 35W, and 45W using a 915-MHz frequency generator and a 2-cm active tip antenna. RF ablations were performed with a bipolar RF system with 2- and 3-cm active tip electrodes. Tissue temperatures were continuously monitored during ablation. Results: The mean short-axis diameters of the coagulation zones were 1.34 {+-} 0.14, 1.45 {+-} 0.13, and 1.74 {+-} 0.11 cm for MW ablation at outputs of 25W, 35W, and 45W. For RF ablation, the corresponding values were 1.16 {+-} 0.09 and 1.26 {+-} 0.14 cm with electrodes having 2- and 3-cm active tips, respectively. The mean coagulation volumes were 2.27 {+-} 0.65, 2.85 {+-} 0.72, and 4.45 {+-} 0.47 cm{sup 3} for MW ablation at outputs of 25W, 35W, and 45W and 1.18 {+-} 0.30 and 2.29 {+-} 0.55 cm{sup 3} got RF ablation with 2- and 3-cm electrodes, respectively. MW ablations at 35W and 45W achieved significantly longer short-axis diameters than RF ablations (P < 0.05). The highest tissue temperature was achieved with MW ablation at 45W (P < 0.05). On histological examination, the extent of the ablation zone in MW ablations was less affected by tissue heterogeneity than that in RF ablations. Conclusion: MW ablation appears to be advantageous with respect to the volume of ablation and the shape of the margin of necrosis compared with RF ablation in an ex vivo bovine udder.

  8. Percutaneous bipolar radiofrequency thermocoagulation for the treatment of lumbar disc herniation.

    PubMed

    Zeng, Zhenhua; Yan, Min; Dai, Yi; Qiu, Weidong; Deng, Shuo; Gu, Xinzhu

    2016-08-01

    Lumbar disc herniation is usually managed with conservative treatment or surgery. However, conservative therapy seldom yields good results, and surgery is associated with multiple complications. This study aimed to assess bipolar radiofrequency thermocoagulation for the treatment of lumbar disc herniation. A total of 168 patients with lumbar disc herniation suitable for radiofrequency thermocoagulation were enrolled and randomized to monopolar radiofrequency thermocoagulation (control group, n=84) or bipolar radiofrequency thermocoagulation (experimental group, n=84) treatment groups. Ablation sites were targeted under CT scan guidance, and consecutive radiofrequency therapy was used. One and two probes were used for monopolar and bipolar thermocoagulation, respectively. Thermocoagulation was achieved at 50°C, 60°C, and 70°C for 60s each, 80°C for 90s, and 92°C for 100s. Symptoms and complications were evaluated using the modified Macnab criteria and Visual Analog Scale at 7, 30, and 180days postoperatively. At 180days, a significantly higher efficacy rate was obtained in the experimental group compared with control patients (91.6% versus 79.7%, P<0.05). No severe complications were occurred in either group. Targeted ablation via bipolar radiofrequency thermocoagulation is efficient for lumbar disc herniation treatment, and should be further explored for broad clinical application. PMID:27234606

  9. [Percutaneous ablation of renal tumors: radiofrequency ablation or cryoablation?].

    PubMed

    Buy, X; Lang, H; Garnon, J; Gangi, A

    2011-09-01

    Percutaneous ablation of renal tumors, including radiofrequency ablation and cryoablation, are increasingly being used for small tumors as an alternative to surgery for poor surgical candidates. Compared to radiofrequency ablation, cryoablation has several advantages: improved volume control and preservation of adjacent structures due to the excellent depiction of the ice ball on CT and MRI; better protection of the collecting system for central tumor with reduced risk of postprocedural urinary fistula. The main pitfall of cryoablation is the higher cost. Therefore, cryoablation should be reserved for the treatment of complex tumors. In this article, we will review the different steps of percutaneous renal tumor ablation procedures including patient selection, technical considerations, and follow-up imaging. PMID:21944236

  10. Effective Treatment of Chronic Radiation Proctitis Using Radiofrequency Ablation

    PubMed Central

    Zhou, Chao; Adler, Desmond C.; Becker, Laren; Chen, Yu; Tsai, Tsung-Han; Figueiredo, Marisa; Schmitt, Joseph M.; Fujimoto, James G.

    2009-01-01

    Endoscopic argon plasma coagulation and bipolar electrocautery are currently preferred treatments for chronic radiation proctitis, but ulcerations and strictures frequently occur. Radiofrequency ablation (RFA) has been successful for mucosal ablation in the esophagus. Here we report the efficacy of RFA with the BarRx Halo90 system in three patients with bleeding from chronic radiation proctitis. In all cases, the procedure was well tolerated and hemostasis was achieved after 1 or 2 RFA sessions. Re-epithelialization of squamous mucosa was observed over areas of prior hemorrhage. No stricturing or ulceration was seen on follow-up up to 19 months after RFA treatment. Real-time endoscopic optical coherence tomography (EOCT) visualized epithelialization and subsurface tissue microvasculature pre- and post-treatment, demonstrating its potential for follow-up assessment of endoscopic therapies. PMID:20593010

  11. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief

    SciTech Connect

    Pérez, Juan J.; Pérez-Cajaraville, Juan J.; Muñoz, Víctor; Berjano, Enrique

    2014-07-15

    Purpose: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a “strip lesion” to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. Methods: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. Results: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m{sup −1}) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. Conclusions: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of

  12. Radiofrequency Ablation Complicated by Skin Burn

    PubMed Central

    Huffman, S.D.; Huffman, N.P.; Lewandowski, Robert J.; Brown, Daniel B.

    2011-01-01

    Radiofrequency (RF) ablation has been increasingly utilized as a minimally invasive treatment for primary and metastatic liver tumors, as well as tumors in the kidneys, bones, and adrenal glands. The development of high-current RF ablation has subsequently led to an increased risk of thermal skin injuries at the grounding pad site. The incidence of skin burns in recent studies ranges from 0.1–3.2% for severe skin burns (second-/third-degree), and from 5–33% for first-degree burns.1–3 PMID:22654258

  13. Radiofrequency ablation of abdominal wall endometrioma.

    PubMed

    Carrafiello, Gianpaolo; Fontana, Federico; Pellegrino, Carlo; Mangini, Monica; Cabrini, Luca; Mariani, Davide; Piacentino, Filippo; Cuffari, Salvatore; Laganà, Domenico; Fugazzola, Carlo

    2009-11-01

    Extraperitoneal endometriosis is the presence of ectopic, functional endometrium outside the peritoneal cavity, and its occurrence is exceedingly rare. Diagnostic imaging--including ultrasound, duplex ultrasonography, and magnetic resonance imaging--in the preoperative assessment of patients with suspected abdominal wall endometriosis (AWE) is helpful for detection and accurate determination of the extent of disease. The treatment of choice for AWE is surgical excision. In addition, medical therapies can be used. We present one case of AWE treated with percutaneous radiofrequency ablation under ultrasound guidance. There were no major complications, and the patient's symptoms improved. In selected patients, radiofrequency ablation can be used safely for the treatment of AWE; however, further studies are needed to confirm this hypothesis. PMID:19184197

  14. Recent progress in radiofrequency ablation therapy for hepatocellular carcinoma.

    PubMed

    Ikeda, Kenji; Osaki, Yukio; Nakanishi, Hiroyuki; Nasu, Akihiro; Kawamura, Yusuke; Jyoko, Koji; Sano, Takatomo; Sunagozaka, Hajime; Uchino, Koji; Minami, Yasunori; Saito, Yu; Nagai, Kazumasa; Inokuchi, Ryosuke; Kokubu, Shigehiro; Kudo, Masatoshi

    2014-01-01

    In order to attain better ablation and more effective management of hepatocellular carcinoma (HCC), new approaches and devices in radiofrequency ablation (RFA) therapy were presented and discussed in a workshop at the 50th Annual Meeting of the Liver Cancer Study Group of Japan. A novel bipolar RFA apparatus was introduced in Japan in January 2013. Hundreds of subjects with HCC were treated with multipolar RFA with varied devices and plans. Among these, no-touch ablation was one of the most useful procedures in the treatment of HCC with the apparatus. In RFA therapy, a few assisting devices and techniques were applied for convenience and improvement of the thermal ablation procedure. Contrast-enhanced ultrasonography and three-dimensional fusion imaging technique using volume data of CT or MRI could improve exact targeting and shorten the treatment time for RFA procedures under ultrasonographic guidance. A more complicated method using a workstation was also reported as being helpful in planning the ablated shape and volume in multineedle RFA. The effective use of sedatives and antianalgesics as well as a novel microwave apparatus with a cooled-tip electrode was also discussed. PMID:25427736

  15. Radiofrequency catheter ablation in pediatric patients with supraventricular arrhythmias.

    PubMed

    Rhodes, L A; Lobban, J H; Schmidt, S B

    1995-01-01

    Radiofrequency (RF) ablation of foci leading to abnormal cardiac rhythms is rapidly becoming the procedure of choice in the management of arrhythmias in adults. This report reviews our initial experience with RF ablation in the pediatric population. PMID:8533398

  16. Photoacoustic characterization of radiofrequency ablation lesions

    NASA Astrophysics Data System (ADS)

    Bouchard, Richard; Dana, Nicholas; Di Biase, Luigi; Natale, Andrea; Emelianov, Stanislav

    2012-02-01

    Radiofrequency ablation (RFA) procedures are used to destroy abnormal electrical pathways in the heart that can cause cardiac arrhythmias. Current methods relying on fluoroscopy, echocardiography and electrical conduction mapping are unable to accurately assess ablation lesion size. In an effort to better visualize RFA lesions, photoacoustic (PA) and ultrasonic (US) imaging were utilized to obtain co-registered images of ablated porcine cardiac tissue. The left ventricular free wall of fresh (i.e., never frozen) porcine hearts was harvested within 24 hours of the animals' sacrifice. A THERMOCOOLR Ablation System (Biosense Webster, Inc.) operating at 40 W for 30-60 s was used to induce lesions through the endocardial and epicardial walls of the cardiac samples. Following lesion creation, the ablated tissue samples were placed in 25 °C saline to allow for multi-wavelength PA imaging. Samples were imaged with a VevoR 2100 ultrasound system (VisualSonics, Inc.) using a modified 20-MHz array that could provide laser irradiation to the sample from a pulsed tunable laser (Newport Corp.) to allow for co-registered photoacoustic-ultrasound (PAUS) imaging. PA imaging was conducted from 750-1064 nm, with a surface fluence of approximately 15 mJ/cm2 maintained during imaging. In this preliminary study with PA imaging, the ablated region could be well visualized on the surface of the sample, with contrasts of 6-10 dB achieved at 750 nm. Although imaging penetration depth is a concern, PA imaging shows promise in being able to reliably visualize RF ablation lesions.

  17. Radiofrequency ablation for benign thyroid nodules.

    PubMed

    Bernardi, S; Stacul, F; Zecchin, M; Dobrinja, C; Zanconati, F; Fabris, B

    2016-09-01

    Benign thyroid nodules are an extremely common occurrence. Radiofrequency ablation (RFA) is gaining ground as an effective technique for their treatment, in case they become symptomatic. Here we review what are the current indications to RFA, its outcomes in terms of efficacy, tolerability, and cost, and also how it compares to the other conventional and experimental treatment modalities for benign thyroid nodules. Moreover, we will also address the issue of treating with this technique patients with cardiac pacemakers (PM) or implantable cardioverter-defibrillators (ICD), as it is a rather frequent occurrence that has never been addressed in detail in the literature. PMID:27098804

  18. Palliative Radiofrequency Ablation for Recurrent Prostate Cancer

    SciTech Connect

    Jindal, Gaurav; Friedman, Marc; Locklin, Julia Wood, Bradford J.

    2006-06-15

    Percutaneous radiofrequency ablation (RFA) is a minimally invasive local therapy for cancer. Its efficacy is now becoming well documented in many different organs, including liver, kidney, and lung. The goal of RFA is typically complete eradication of a tumor in lieu of an invasive surgical procedure. However, RFA can also play an important role in the palliative care of cancer patients. Tumors which are surgically unresectable and incompatible for complete ablation present the opportunity for RFA to be used in a new paradigm. Cancer pain runs the gamut from minor discomfort relieved with mild pain medication to unrelenting suffering for the patient, poorly controlled by conventional means. RFA is a tool which can potentially palliate intractable cancer pain. We present here a case in which RFA provided pain relief in a patient with metastatic prostate cancer with pain uncontrolled by conventional methods.

  19. Radiofrequency thermal ablation of renal tumors.

    PubMed

    De Filippo, Massimo; Bozzetti, Francesca; Martora, Rosa; Zagaria, Raffaella; Ferretti, Stefania; Macarini, Luca; Brunese, Luca; Rotondo, Antonio; Rossi, Cristina

    2014-07-01

    Percutaneous radiofrequency ablation (PRFA) of renal malignancies is currently a therapeutic option for patients who are not able to undergo surgery. Some authors consider PRFA as the therapeutic standard in the treatment of renal neoplasms in non-operable patients due to comorbid conditions and in patients with mild-moderate renal failure, to preserve residual renal functionality. The use of PRFA has become more and more widespread due to a rise in the incidental detection of renal cell carcinomas with the ever-increasing use of Imaging for the study of abdominal diseases. Clinical studies indicate that RF ablation is an effective therapy with a low level of risk of complications, which provides good results in selected patients over short and medium term periods of time, however up to now few long-term studies have been carried out which can confirm the effectiveness of PRFA. PMID:25024061

  20. Cooled radiofrequency ablation for bilateral greater occipital neuralgia.

    PubMed

    Vu, Tiffany; Chhatre, Akhil

    2014-01-01

    This report describes a case of bilateral greater occipital neuralgia treated with cooled radiofrequency ablation. The case is considered in relation to a review of greater occipital neuralgia, continuous thermal and pulsed radiofrequency ablation, and current medical literature on cooled radiofrequency ablation. In this case, a 35-year-old female with a 2.5-year history of chronic suboccipital bilateral headaches, described as constant, burning, and pulsating pain that started at the suboccipital region and radiated into her vertex. She was diagnosed with bilateral greater occipital neuralgia. She underwent cooled radiofrequency ablation of bilateral greater occipital nerves with minimal side effects and 75% pain reduction. Cooled radiofrequency ablation of the greater occipital nerve in challenging cases is an alternative to pulsed and continuous RFA to alleviate pain with less side effects and potential for long-term efficacy. PMID:24716017

  1. A rare complication of radiofrequency ablation: skin burn.

    PubMed

    Ertuğrul, İlker; Karagöz, Tevfik; Aykan, Hayrettin H

    2015-10-01

    Radiofrequency ablation is the first-line treatment for arrhythmias with high success and low complication rates. Skin burns have been reported rarely after electrophysiological procedures, especially procedures in which higher-power energy is used and multiple ablations are performed. Here, we report a case of skin burn that developed after radiofrequency ablation for ventricular tachycardia originating from the right ventricular outflow tract. PMID:25613639

  2. Radiofrequency ablation of hepatocellular carcinoma: Current status

    PubMed Central

    Minami, Yasunori; Kudo, Masatoshi

    2010-01-01

    Ablation therapy is one of the best curative treatment options for malignant liver tumors, and can be an alternative to resection. Radiofrequency ablation (RFA) of primary and secondary liver cancers can be performed safely using percutaneous, laparoscopic, or open surgical techniques, and RFA has markedly changed the treatment strategy for small hepatocellular carcinoma (HCC). Percutaneous RFA can achieve the same overall and disease-free survival as surgical resection for patients with small HCC. The use of a laparoscopic or open approach allows repeated placements of RFA electrodes at multiple sites to ablate larger tumors. RFA combined with transcatheter arterial chemoembolization will make the treatment of larger tumors a clinically viable treatment alternative. However, an accurate evaluation of treatment response is very important to secure successful RFA therapy. Since a sufficient safety margin (at least 0.5 cm) can prevent local tumor recurrences, an accurate evaluation of treatment response is very important to secure successful RFA therapy. To minimize complications of RFA, clinicians should be familiar with the imaging features of each type of complication. Appropriate management of complications is essential for successful RFA treatment. PMID:21179308

  3. Retrograde Transpubic Approach for Percutaneous Radiofrequency Ablation and Cementoplasty of Acetabular Metastasis

    PubMed Central

    Bauones, Salem; Freire, Veronique; Moser, Thomas P.

    2015-01-01

    We report a case of painful and disabling anterior acetabular bone metastasis treated with bipolar radiofrequency ablation and cementoplasty. Due to the high risk of complications related to the proximity of the femoral neurovascular structures with a direct approach, we successfully performed a retrograde transpubic approach under combined CT and fluoroscopic guidance. In the present report, we describe this approach detailing its indications, advantages, and the technical tips to achieve a safe and satisfactory procedure. PMID:26491595

  4. Three-dimension finite-element analyses of multiple electrodes bipolar RF global endometrial ablation

    NASA Astrophysics Data System (ADS)

    Hu, Tao; Panhao, Tang; Xiao, Jiahua

    2015-03-01

    Radio-frequency ablation (RFA) is a minimally invasive surgical procedure to thermally ablate the targeted diseased tissue. There have been many finite-element method (FEM) studies of cardiac and hepatic RFA, but hardly find any FEM study on endometrial ablation for abnormal uterine bleeding. In this paper, a FEM model was generated to analyze the temperature distribution of bipolar RF global endometrial ablation with three pairs of bipolar electrodes placed at the perimeter of the uterine cavity. COMSOL was utilized to calculate the RF electric fields and temperature fields by numerically solving the bioheat equation in the triangle uterine cavity range. The 55°C isothermal surfaces show the shape of the ablation dimensions (depth and width), which reasonably matched the experimental results.

  5. Emerging indications of endoscopic radiofrequency ablation

    PubMed Central

    Becq, Aymeric; Camus, Marine; Rahmi, Gabriel; de Parades, Vincent; Marteau, Philippe

    2015-01-01

    Introduction Radiofrequency ablation (RFA) is a well-validated treatment of dysplastic Barrett's esophagus. Other indications of endoscopic RFA are under evaluation. Results Four prospective studies (total 69 patients) have shown that RFA achieved complete remission of early esophageal squamous intra-epithelial neoplasia at a rate of 80%, but with a substantial risk of stricture. In the setting of gastric antral vascular ectasia, two prospective monocenter studies, and a retrospective multicenter study, (total 51 patients), suggest that RFA is efficacious in terms of reducing transfusion dependency. In the setting of chronic hemorrhagic radiation proctopathy, a prospective monocenter study and a retrospective multicenter study (total 56 patients) suggest that RFA is an efficient treatment. A retrospective comparative study (64 patients) suggests that RFA improves stents patency in malignant biliary strictures. Conclusions Endoscopic RFA is an upcoming treatment modality in early esophageal squamous intra-epithelial neoplasia, as well as in gastric, rectal, and biliary diseases. PMID:26279839

  6. Radiofrequency Ablation Therapy for Solid Tumors

    SciTech Connect

    Kam, Anthony

    2002-12-04

    Surgical resection, systemic chemotherapy, and local radiation have been the conventional treatments for localized solid cancer. Because certain patients are not candidates for tumor resection and because many tumors are poorly responsive to chemotherapy and radiation, there has been an impetus to develop alternative therapies. Radiofrequency ablation (RFA) is a minimally invasive therapy for localized solid cancers that has gained considerable attention in the last 12 years. Advantages of minimally invasive therapies over surgery include less recovery time, lower morbidity and mortality, eligibility of more patients, and lower cost. RFA has been applied most extensively to inoperable hepatic tumors. It is investigational for tumors in the kidney, lung, bone, breast, and adrenal gland. This colloquium will review the mechanism, techniques, limitations, and clinical applications of RFA. The ultimate role that RFA will play in cancer therapy will depend on the results of long-term follow-up and prospective randomized trials.

  7. Radiofrequency ablation during continuous saline infusion can extend ablation margins

    PubMed Central

    Ishikawa, Toru; Kubota, Tomoyuki; Horigome, Ryoko; Kimura, Naruhiro; Honda, Hiroki; Iwanaga, Akito; Seki, Keiichi; Honma, Terasu; Yoshida, Toshiaki

    2013-01-01

    AIM: To determine whether fluid injection during radiofrequency ablation (RFA) can increase the coagulation area. METHODS: Bovine liver (1-2 kg) was placed on an aluminum tray with a return electrode affixed to the base, and the liver was punctured by an expandable electrode. During RFA, 5% glucose; 50% glucose; or saline fluid was infused continuously at a rate of 1.0 mL/min through the infusion line connected to the infusion port. The area and volume of the thermocoagulated region of bovine liver were determined after RFA. The Joule heat generated was determined from the temporal change in output during the RFA experiment. RESULTS: No liquid infusion was 17.3 ± 1.6 mL, similar to the volume of a 3-cm diameter sphere (14.1 mL). Mean thermocoagulated volume was significantly larger with continuous infusion of saline (29.3 ± 3.3 mL) than with 5% glucose (21.4 ± 2.2 mL), 50% glucose (16.5 ± 0.9 mL) or no liquid infusion (17.3 ± 1.6 mL). The ablated volume for RFA with saline was approximately 1.7-times greater than for RFA with no liquid infusion, representing a significant difference between these two conditions. Total Joule heat generated during RFA was highest with saline, and lowest with 50% glucose. CONCLUSION: RFA with continuous saline infusion achieves a large ablation zone, and may help inhibit local recurrence by obtaining sufficient ablation margins. RFA during continuous saline infusion can extend ablation margins, and may be prevent local recurrence. PMID:23483097

  8. Thermal Ablation for Benign Thyroid Nodules: Radiofrequency and Laser

    PubMed Central

    Lee, Jeong Hyun; Valcavi, Roberto; Pacella, Claudio M.; Rhim, Hyunchul; Na, Dong Gyu

    2011-01-01

    Although ethanol ablation has been successfully used to treat cystic thyroid nodules, this procedure is less effective when the thyroid nodules are solid. Radiofrequency (RF) ablation, a newer procedure used to treat malignant liver tumors, has been valuable in the treatment of benign thyroid nodules regardless of the extent of the solid component. This article reviews the basic physics, techniques, applications, results, and complications of thyroid RF ablation, in comparison to laser ablation. PMID:21927553

  9. Radiofrequency ablation of intrahepatic cholangiocarcinoma: preliminary experience.

    PubMed

    Carrafiello, Gianpaolo; Laganà, Domenico; Cotta, Elisa; Mangini, Monica; Fontana, Federico; Bandiera, Francesca; Fugazzola, Carlo

    2010-08-01

    The purpose of this study was to evaluate the safety and efficacy of percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) in patients with intrahepatic cholangiocarcinoma (ICCA) in a small, nonrandomized series. From February 2004 to July 2008, six patients (four men and two women; mean age 69.8 years [range 48 to 83]) with ICCA underwent percutaneous US-guided RFA. Preintervetional transarterial embolization was performed in two cases to decrease heat dispersion during RFA in order to increase the area of ablation. The efficacy of RFA was evaluated using contrast-enhanced dynamic computed tomography (CT) 1 month after treatment and then every 3 months thereafter. Nine RFA sessions were performed for six solid hepatic tumors in six patients. The duration of follow-up ranged from 13 to 21 months (mean 17.5). Posttreatment CT showed total necrosis in four of six tumors after one or two RFA sessions. Residual tumor was observed in two patients with larger tumors (5 and 5.8 cm in diameter). All patients tolerated the procedure, and there with no major complications. Only 1 patient developed post-RFA syndrome (pain, fever, malaise, and leukocytosis), which resolved with oral administration of acetaminophen. Percutaneous RFA is a safe and effective treatment for patients with hepatic tumors: It is ideally suited for those who are not eligible for surgery. Long-term follow-up data regarding local and systemic recurrence and survival are still needed. PMID:20411389

  10. Current oncologic applications of radiofrequency ablation therapies

    PubMed Central

    Shah, Dhruvil R; Green, Sari; Elliot, Angelina; McGahan, John P; Khatri, Vijay P

    2013-01-01

    Radiofrequency ablation (RFA) uses high frequency alternating current to heat a volume of tissue around a needle electrode to induce focal coagulative necrosis with minimal injury to surrounding tissues. RFA can be performed via an open, laparoscopic, or image guided percutaneous approach and be performed under general or local anesthesia. Advances in delivery mechanisms, electrode designs, and higher power generators have increased the maximum volume that can be ablated, while maximizing oncological outcomes. In general, RFA is used to control local tumor growth, prevent recurrence, palliate symptoms, and improve survival in a subset of patients that are not candidates for surgical resection. It’s equivalence to surgical resection has yet to be proven in large randomized control trials. Currently, the use of RFA has been well described as a primary or adjuvant treatment modality of limited but unresectable hepatocellular carcinoma, liver metastasis, especially colorectal cancer metastases, primary lung tumors, renal cell carcinoma, boney metastasis and osteoid osteomas. The role of RFA in the primary treatment of early stage breast cancer is still evolving. This review will discuss the general features of RFA and outline its role in commonly encountered solid tumors. PMID:23671734

  11. Radiofrequency Ablation of Intrahepatic Cholangiocarcinoma: Preliminary Experience

    SciTech Connect

    Carrafiello, Gianpaolo Lagana, Domenico; Cotta, Elisa; Mangini, Monica; Fontana, Federico; Bandiera, Francesca; Fugazzola, Carlo

    2010-08-15

    The purpose of this study was to evaluate the safety and efficacy of percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) in patients with intrahepatic cholangiocarcinoma (ICCA) in a small, nonrandomized series. From February 2004 to July 2008, six patients (four men and two women; mean age 69.8 years [range 48 to 83]) with ICCA underwent percutaneous US-guided RFA. Preintervetional transarterial embolization was performed in two cases to decrease heat dispersion during RFA in order to increase the area of ablation. The efficacy of RFA was evaluated using contrast-enhanced dynamic computed tomography (CT) 1 month after treatment and then every 3 months thereafter. Nine RFA sessions were performed for six solid hepatic tumors in six patients. The duration of follow-up ranged from 13 to 21 months (mean 17.5). Posttreatment CT showed total necrosis in four of six tumors after one or two RFA sessions. Residual tumor was observed in two patients with larger tumors (5 and 5.8 cm in diameter). All patients tolerated the procedure, and there with no major complications. Only 1 patient developed post-RFA syndrome (pain, fever, malaise, and leukocytosis), which resolved with oral administration of acetaminophen. Percutaneous RFA is a safe and effective treatment for patients with hepatic tumors: It is ideally suited for those who are not eligible for surgery. Long-term follow-up data regarding local and systemic recurrence and survival are still needed.

  12. The use of radiofrequency catheter ablation to cure dilated cardiomyopathy.

    PubMed

    Schmidt, S B; Lobban, J H; Reddy, S; Hoelper, M; Palmer, D L

    1997-01-01

    Incessant supraventricular tachycardia can cause a dilated cardiomyopathy. This article discusses the case of a 55-year-old woman whose cardiomyopathy was reversed when she underwent successful radiofrequency catheter ablation of a unifocal atrial tachycardia. PMID:9197188

  13. Factors Limiting Complete Tumor Ablation by Radiofrequency Ablation

    SciTech Connect

    Paulet, Erwan Aube, Christophe; Pessaux, Patrick; Lebigot, Jerome; Lhermitte, Emilie; Oberti, Frederic; Ponthieux, Anne; Cales, Paul; Ridereau-Zins, Catherine; Pereira, Philippe L.

    2008-01-15

    The purpose of this study was to determine radiological or physical factors to predict the risk of residual mass or local recurrence of primary and secondary hepatic tumors treated by radiofrequency ablation (RFA). Eighty-two patients, with 146 lesions (80 hepatocellular carcinomas, 66 metastases), were treated by RFA. Morphological parameters of the lesions included size, location, number, ultrasound echogenicity, computed tomography density, and magnetic resonance signal intensity were obtained before and after treatment. Parameters of the generator were recorded during radiofrequency application. The recurrence-free group was statistically compared to the recurrence and residual mass groups on all these parameters. Twenty residual masses were detected. Twenty-nine lesions recurred after a mean follow-up of 18 months. Size was a predictive parameter. Patients' sex and age and the echogenicity and density of lesions were significantly different for the recurrence and residual mass groups compared to the recurrence-free group (p < 0.05). The presence of an enhanced ring on the magnetic resonance control was more frequent in the recurrence and residual mass groups. In the group of patients with residual lesions, analysis of physical parameters showed a significant increase (p < 0.05) in the time necessary for the temperature to rise. In conclusion, this study confirms risk factors of recurrence such as the size of the tumor and emphasizes other factors such as a posttreatment enhanced ring and an increase in the time necessary for the rise in temperature. These factors should be taken into consideration when performing RFA and during follow-up.

  14. Sustained Growth of the Ex Vivo Ablation Zones' Critical Short Axis Using Gas-cooled Radiofrequency Applicators

    SciTech Connect

    Rempp, Hansjoerg; Scharpf, Marcus; Voigtlaender, Matthias; Schraml, Christina; Schmidt, Diethard; Fend, Falko; Claussen, Claus D.; Enderle, Markus D.; Pereira, Philippe L.; Clasen, Stephan

    2011-02-15

    Purpose: To evaluate the ablation zones created with a gas-cooled bipolar radiofrequency applicator performed on ex vivo bovine liver tissue. Materials and Methods: A total of 320 ablations with an internally gas-cooled bipolar radiofrequency applicator were performed on fresh ex vivo bovine liver tissue, varying the ablation time (5, 10, 15, and 20 min), power (20, 30, 40, and 50 W), and gas pressure of the CO{sub 2} used for cooling (585, 600, 615, 630, 645 psi), leading to a total of 80 different parameter combinations. Size and shape of the white coagulation zone were assessed. Results: The largest complete ablation zone was achieved after 20 min of implementing 50 W and 645 psi, resulting in a short axis of mean 46 {+-} 1 mm and a long axis of 56 {+-} 2 mm (mean {+-} standard deviation). Short-axis diameters increased between 5 and 20 min of ablation time at 585 psi (increase of the short axis was 45% at 30 W, 29% at 40 W, and 39% at 50 W). This increase was larger at 645 psi (113% at 30 W, 67% at 40 W, and 70% at 50 W). Macroscopic assessment and NADH (nicotinamide adenine dinucleotide) staining revealed incompletely ablated tissue along the needle track in 18 parameter combinations including low-power settings (20 and 30 W) and different cooling levels and ablation times. Conclusion: Gas-cooled radiofrequency applicators increase the short-axis diameter of coagulation in an ex vivo setting if appropriate parameters are selected.

  15. Endoscopic radiofrequency ablation for malignant biliary strictures

    PubMed Central

    WANG, FEI; LI, QUANPENG; ZHANG, XIUHUA; JIANG, GUOBING; GE, XIANXIU; YU, HONG; NIE, JUNJIE; JI, GUOZHONG; MIAO, LIN

    2016-01-01

    Endoscopic radiofrequency ablation (RFA) is a novel palliation therapy for malignant biliary stricture; however, its feasibility and safety has not yet been clearly defined. The aim of the present study was to evaluate the feasibility and safety of endoscopic RFA for the treatment of malignant biliary strictures. A total of 12 patients treated by endoscopic RFA between December 2011 and October 2013 were retrospectively analyzed. Adverse events within 30 days post-intervention, stricture diameters prior to and following RFA, stent patency and survival time were investigated. A total of 12 patients underwent 20 RFA procedures as a treatment for malignant biliary strictures. Two patients required repeated elective RFA (4 and 6 times, respectively). All 20 RFA procedures were successfully performed without technical problems. During a 30 day period following each RFA procedure, two patients experienced fever (38.2 and 38.9°C, respectively) and another patient exhibited post-endoscopic retrograde cholangiopancreatography pancreatitis. The 30- and 90-day mortality rates were 0 and 8.3%, respectively. Mean stricture diameter prior to RFA was 5.3 mm (standard deviation (SD), 0.9 mm; range, 5–8 mm), and the mean diameter following RFA was 12.6 mm (SD, 3.1 mm; range, 8–15 mm). There was a significant increase of 7.3 mm in the bile duct diameter following RFA in comparison with prior to RFA (t=8.6; P≤0.001). Of the 11 patients with stents inserted following RFA, the median stent patency was 125.0 days [95% confidence interval (CI), 94.7–155.3 days]. Extrapolated median survival following the first RFA was 232 days (95% CI, 94.3–369.7 days). In conclusion, RFA appears to be an efficient and safe treatment strategy for the palliation of unresectable malignant biliary strictures. PMID:27284336

  16. Saline-Linked Surface Radiofrequency Ablation

    PubMed Central

    Topp, Stefan A.; McClurken, Michael; Lipson, David; Upadhya, Gundumi A.; Ritter, Jon H.; Linehan, David; Strasberg, Steven M.

    2004-01-01

    Summary Background Data: Saline-linked surface radiofrequency (RF) ablation is a new technique for applying RF energy to surfaces. The surface is cooled, which prevents charring and results in deeper coagulation. However, subsurface heating may lead to steam formation and a form of tissue disruption called steam popping. We determined parameters that predict steam popping and depth of tissue destruction under nonpopping conditions. A commercially available saline-linked surface RF cautery device (Floating Ball 3.0, TissueLink, Inc.) was used. Methods: One hundred eighty circular lesions were created varying in lesion diameter, duration, power, and inflow occlusion. Variables affecting popping were determined. Then factors influencing lesion depth were studied at fixed nonpopping diameter/power combinations (1 cm/10W, 2 cm/15W, 4 cm/60W). Tissue viability was determined in selected samples by staining of tissue NADH. Results: The probability of steam popping was directly related to power level and inflow occlusion, and indirectly related to lesion diameter. Depth of injury under safe nonpopping conditions was directly related to power, lesion size, and inflow occlusion. Maximum depth in excess of 20 mm was achieved using a 4 cm diameter at 60W with inflow occlusion. Microscopy of NADH-stained tissues showed a complete cell killing in the macroscopically visible coagulated area. Conclusions: Steam popping can be avoided by selecting power level/lesion diameter combinations. Tissue destruction to 20 mm can be safely achieved with short periods of inflow occlusion. The device has promise as a treatment of superficial tumors and close resection margins. PMID:15024313

  17. Percutaneous radiofrequency ablation versus surgical radiofrequency ablation for malignant liver tumours: the long-term results

    PubMed Central

    Wong, John; Lee, Kit-Fai; Yu, Simon Chun-Ho; Lee, Paul Sing-Fun; Cheung, Yue-Sun; Chong, Ching-Ning; Ip, Philip Ching-Tak; Lai, Paul Bo-San

    2013-01-01

    Background Radiofrequency ablation (RFA) has been used to treat hepatocellular carcinoma (HCC) and liver metastases for more than 10 years with promising early outcomes. Preliminary results comparing percutaneous and surgical approaches have shown no difference in short-term outcomes. In this study, the longer-term outcomes were presented. Methods Patients with liver malignancies treated by RFA were prospectively studied from 2003 to 2011. Post-ablation assessment by computed tomography (CT) scan and serum biochemistry was performed at regular intervals. Recurrence rates and long-term survival were analysed. Results A total of 233 patients with liver malignancies (75.5% HCC and 24.5% liver metastases) were analysed. Three RFA approaches were used (percutaneous 58.4%, laparoscopic 9.4% and open 32.2%). The median follow-up time was 29 months. Complete ablation was achieved in 83.7%, with no difference between the two approaches. More wound and chest complications were observed in the surgical group. Intra-hepatic recurrences were observed in 69.5%; extra-hepatic recurrences were detected in 22.3%, with no difference between the two groups. There was no statistical difference between the two approaches in overall 1-, 3- and 5-year survival. Conclusion An extended period of follow-up in patients with liver malignancies showed that RFA is an effective treatment. No difference was demonstrated between the percutaneous and surgical approach, in terms of recurrence and survival. PMID:23458320

  18. Optimization of the generator settings for endobiliary radiofrequency ablation

    PubMed Central

    Barret, Maximilien; Leblanc, Sarah; Vienne, Ariane; Rouquette, Alexandre; Beuvon, Frederic; Chaussade, Stanislas; Prat, Frederic

    2015-01-01

    AIM: To determine the optimal generator settings for endobiliary radiofrequency ablation. METHODS: Endobiliary radiofrequency ablation was performed in live swine on the ampulla of Vater, the common bile duct and in the hepatic parenchyma. Radiofrequency ablation time, “effect”, and power were allowed to vary. The animals were sacrificed two hours after the procedure. Histopathological assessment of the depth of the thermal lesions was performed. RESULTS: Twenty-five radiofrequency bursts were applied in three swine. In the ampulla of Vater (n = 3), necrosis of the duodenal wall was observed starting with an effect set at 8, power output set at 10 W, and a 30 s shot duration, whereas superficial mucosal damage of up to 350 μm in depth was recorded for an effect set at 8, power output set at 6 W and a 30 s shot duration. In the common bile duct (n = 4), a 1070 μm, safe and efficient ablation was obtained for an effect set at 8, a power output of 8 W, and an ablation time of 30 s. Within the hepatic parenchyma (n = 18), the depth of tissue damage varied from 1620 μm (effect = 8, power = 10 W, ablation time = 15 s) to 4480 μm (effect = 8, power = 8 W, ablation time = 90 s). CONCLUSION: The duration of the catheter application appeared to be the most important parameter influencing the depth of the thermal injury during endobiliary radiofrequency ablation. In healthy swine, the currently recommended settings of the generator may induce severe, supratherapeutic tissue damage in the biliary tree, especially in the high-risk area of the ampulla of Vater. PMID:26566429

  19. Radiofrequency Ablation of Thyroid Nodules: Basic Principles and Clinical Application

    PubMed Central

    Shin, Ji Hoon; Baek, Jung Hwan; Ha, Eun Ju; Lee, Jeong Hyun

    2012-01-01

    Radiofrequency (RF) ablation has been gaining popularity as a minimally invasive treatment for benign thyroid nodules regardless of the extent of the solid component. RF ablation of benign nodules demonstrated volume reductions of 33–58% after one month and 51–85% after six months, while solving nodule-related clinical problems. RF ablation has recently shown positive short-term results for locoregional control as well as symptom improvement in patients with recurrent thyroid cancers. This paper reviews the basic physics, indications, patient preparation, devices, procedures, clinical results, and complications of RF ablation. PMID:23133449

  20. Successful Management of Atrio-Esophageal Fistula after Cardiac Radiofrequency Catheter Ablation

    PubMed Central

    Shim, Hun Bo; Kim, Chilsung; Kim, Hong-Kwan

    2013-01-01

    An increase in cardiac radiofrequency catheter ablation for treating refractory atrial fibrillation has resulted in an increased prevalence of complications. Among numerous complications of radiofrequency catheter ablation, atrio-esophageal fistula, although rare, is known to have fatal results. We report a case of successful management of an atrio-esophageal fistula as a complication of cardiac radiofrequency catheter ablation. PMID:23614102

  1. Endovenous radiofrequency ablation for the treatment of varicose veins

    PubMed Central

    Kayssi, Ahmed; Pope, Marc; Vucemilo, Ivica; Werneck, Christiane

    2015-01-01

    Summary Varicose veins are a common condition that can be treated surgically. Available operative modalities include saphenous venous ligation and stripping, phlebectomy, endovenous laser therapy and radiofrequency ablation. Radiofrequency ablation is the newest of these technologies, and to our knowledge our group was the first to use it in Canada. Our experience suggests that it is a safe and effective treatment for varicose veins, with high levels of patient satisfaction reported at short-term follow-up. More studies are needed to assess long-term effectiveness and compare the various available treatment options for varicose veins. PMID:25799244

  2. Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation.

    PubMed

    Kuck, Karl-Heinz; Brugada, Josep; Fürnkranz, Alexander; Metzner, Andreas; Ouyang, Feifan; Chun, K R Julian; Elvan, Arif; Arentz, Thomas; Bestehorn, Kurt; Pocock, Stuart J; Albenque, Jean-Paul; Tondo, Claudio

    2016-06-01

    Background Current guidelines recommend pulmonary-vein isolation by means of catheter ablation as treatment for drug-refractory paroxysmal atrial fibrillation. Radiofrequency ablation is the most common method, and cryoballoon ablation is the second most frequently used technology. Methods We conducted a multicenter, randomized trial to determine whether cryoballoon ablation was noninferior to radiofrequency ablation in symptomatic patients with drug-refractory paroxysmal atrial fibrillation. The primary efficacy end point in a time-to-event analysis was the first documented clinical failure (recurrence of atrial fibrillation, occurrence of atrial flutter or atrial tachycardia, use of antiarrhythmic drugs, or repeat ablation) following a 90-day period after the index ablation. The noninferiority margin was prespecified as a hazard ratio of 1.43. The primary safety end point was a composite of death, cerebrovascular events, or serious treatment-related adverse events. Results A total of 762 patients underwent randomization (378 assigned to cryoballoon ablation and 384 assigned to radiofrequency ablation). The mean duration of follow-up was 1.5 years. The primary efficacy end point occurred in 138 patients in the cryoballoon group and in 143 in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 34.6% and 35.9%, respectively; hazard ratio, 0.96; 95% confidence interval [CI], 0.76 to 1.22; P<0.001 for noninferiority). The primary safety end point occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 10.2% and 12.8%, respectively; hazard ratio, 0.78; 95% CI, 0.52 to 1.18; P=0.24). Conclusions In this randomized trial, cryoballoon ablation was noninferior to radiofrequency ablation with respect to efficacy for the treatment of patients with drug-refractory paroxysmal atrial fibrillation, and there was no significant difference between the two methods with regard to

  3. Osteoid Osteoma: Experience with Laser- and Radiofrequency-Induced Ablation

    SciTech Connect

    Gebauer, Bernhard Tunn, Per-Ulf; Gaffke, Gunnar; Melcher, Ingo; Felix, Roland; Stroszczynski, Christian

    2006-04-15

    The purpose of this study was to analyze the clinical outcome of osteoid osteoma treated by thermal ablation after drill opening. A total of 17 patients and 20 procedures were included. All patients had typical clinical features (age, pain) and a typical radiograph showing a nidus. In 5 cases, additional histological specimens were acquired. After drill opening of the osteoid osteoma nidus, 12 thermal ablations were induced by laser interstitial thermal therapy (LITT) (9F Power-Laser-Set; Somatex, Germany) and 8 ablations by radiofrequency ablation (RFA) (RITA; StarBurst, USA). Initial clinical success with pain relief has been achieved in all patients after the first ablation. Three patients had an osteoid osteoma recurrence after 3, 9, and 10 months and were successfully re-treated by thermal ablation. No major complication and one minor complication (sensible defect) were recorded. Thermal ablation is a safe and minimally invasive therapy option for osteoid osteoma. Although the groups are too small for a comparative analysis, we determined no difference between laser- and radiofrequency-induced ablation in clinical outcome after ablation.

  4. Radiofrequency (electrosurgical) ablation of articular cartilage: a study in sheep.

    PubMed

    Turner, A S; Tippett, J W; Powers, B E; Dewell, R D; Mallinckrodt, C H

    1998-09-01

    The objective of this study was to examine the effect of a bipolar ablation probe on experimentally roughened articular cartilage and compare it with the traditional mechanical shaving technique using the knee joint of sheep. Twenty-eight skeletally mature ewes were divided randomly into two groups: one group was treated with a rotating shaving device and another group was treated using the bipolar ablation probe (Bipolar Arthroscopic Probe; Electroscope, Inc, Boulder, CO). Animals were killed at 0, 6, 12, and 24 weeks, and histological sections of the experimental limbs were compared with sections of the opposite limb using a modified Mankin scale. The following variables were used to determine scores: surface (0-6), cells (0-4), hypocellularity (0-3), matrix staining (transitional zone [0-4], radiate zone [0-4], and focal empty lacunae or hypereosinophilic cells (0-3). Differences in scores for all response variables were calculated as treated limb minus sham limb. Response variables were formed: score >0 recoded as 1 (favorable response treated better than sham), score of 0 recoded as 2 (neutral response no differences), and score <0 recoded as 3 (unfavorable response treated worse than sham). Bipolar ablative probe-treated limbs had 14.29% favorable responses and 35.71% favorable or neutral responses, whereas shave-treated limbs had 0% favorable and only 7.14% favorable or neutral responses. For all variables, bipolar ablative probe-treated limbs had more favorable responses. The less severe histological change in the bipolar ablative probe-treated joints compared with the shave-treated joints suggests that bipolar ablation of articular cartilage may be a better treatment for chondromalacia than the usual shaving methods of debridement. Further, there were no pathological changes in the subchondral bone. PMID:9754476

  5. Novel catheter enabling simultaneous radiofrequency ablation and optical coherence reflectometry

    PubMed Central

    Herranz, D.; Lloret, Juan; Jiménez-Valero, Santiago; Rubio-Guivernau, J. L.; Margallo-Balbás, Eduardo

    2015-01-01

    A novel radiofrequency ablation catheter has been developed with integrated custom designed optics, enabling real-time monitoring of radiofrequency ablation procedures through polarization-sensitive optical coherence reflectometry. The optics allow for proper tissue illumination through a view-port machined in the catheter tip, thus providing lesion depth control over the RF ablation treatment. The system was verified in an in-vitro model of swine myocardium. Optical performance and thermal stability was confirmed after more than 25 procedures, without any damage to the optical assembly induced by thermal stress or material degradation. The use of this catheter in RF ablation treatments may make possible to assess lesion depth during therapy, thus translating into a reduction of potential complications on the procedure. PMID:26417499

  6. Technical development of a new semispherical radiofrequency bipolar device (RONJA): ex vivo and in vivo studies.

    PubMed

    Vavra, Petr; Penhaker, Marek; Grepl, Jan; Jurcikova, Jana; Palecek, Jiri; Crha, Michal; Nowakova, Jana; Hasal, Martin; Skrobankova, Martina; Ostruszka, Petr; Ihnat, Peter; Delongova, Patricie; Salounova, Dana; Habib, Nagy A; Zonca, Pavel

    2014-01-01

    The aim of this study is to inform about the development of a new semispherical surgical instrument for the bipolar multielectrode radiofrequency liver ablation. Present tools are universal; however they have several disadvantages such as ablation of healthy tissue, numerous needle punctures, and, therefore, longer operating procedure. Our newly designed and tested semispherical surgical tool can solve some of these disadvantages. By conducting an in vivo study on a set of 12 pigs, randomly divided into two groups, we have compared efficiency of the newly developed instrument with the commonly used device. Statistical analysis showed that there were no significant differences between the groups. On average, the tested instrument RONJA had shorter ablation time in both liver lobes and reduced the total operating time. The depth of the thermal alteration was on average 4 mm larger using the newly tested instrument. The new radiofrequency method described in this study could be used in open liver surgery for the treatment of small liver malignancies (up to 2 cm) in a single application with the aim of saving healthy liver parenchyma. Further experimental studies are needed to confirm these results before clinical application of the method in the treatment of human liver malignancies. PMID:24812620

  7. Technical Development of a New Semispherical Radiofrequency Bipolar Device (RONJA): Ex Vivo and In Vivo Studies

    PubMed Central

    Vavra, Petr; Jurcikova, Jana; Crha, Michal; Skrobankova, Martina; Ostruszka, Petr; Ihnat, Peter; Delongova, Patricie; Salounova, Dana; Habib, Nagy A.; Zonca, Pavel

    2014-01-01

    The aim of this study is to inform about the development of a new semispherical surgical instrument for the bipolar multielectrode radiofrequency liver ablation. Present tools are universal; however they have several disadvantages such as ablation of healthy tissue, numerous needle punctures, and, therefore, longer operating procedure. Our newly designed and tested semispherical surgical tool can solve some of these disadvantages. By conducting an in vivo study on a set of 12 pigs, randomly divided into two groups, we have compared efficiency of the newly developed instrument with the commonly used device. Statistical analysis showed that there were no significant differences between the groups. On average, the tested instrument RONJA had shorter ablation time in both liver lobes and reduced the total operating time. The depth of the thermal alteration was on average 4 mm larger using the newly tested instrument. The new radiofrequency method described in this study could be used in open liver surgery for the treatment of small liver malignancies (up to 2 cm) in a single application with the aim of saving healthy liver parenchyma. Further experimental studies are needed to confirm these results before clinical application of the method in the treatment of human liver malignancies. PMID:24812620

  8. A technique for periorbital syringomas: intralesional radiofrequency ablation

    PubMed Central

    Huang, Li-Ping; Zhang, Leng; Wang, Xing-Lin; Liu, Xiao-Cui; Jiang, Tian-Yu; Lin, Bi-Weng

    2012-01-01

    AIM To evaluate the efficacy of intralesional radiofrequency ablation in the treatment of periorbital syringomas. METHODS We tried the intralesional radiofrequency ablation for 64 patients with periorbital syringomas from 2007 to 2011. The operation was performed under 2.5 loupe magnifications. The handpiece was assembled with a needle electrode and connected to the radiofrequency ablation apparatus. The electrode was then inserted into the target lesions in dermis and delivering injury to the base of these tumors. Results were assessed clinically by comparing pre- and post-treatment photographs and patient satisfaction rates. RESULTS Clinical improvement increased with each subsequent treatment session. The percent of patients whose clinic improvement grade were≥3 after each session was respectively 71.9%(Session1), 83.3%(Session2), and 100%(Session3). The statistical results indicated the concordance of the clinical assessment and the satisfaction level of patients (kappa=0.78 of the session1; kappa=0.82 of the session2). The majority of patients had good or excellent cosmetic results. Postoperatively, there were no permanent side effects or recurrences. CONCLUSION As a new technique of minimally invasion, the intralesional radiofrequency ablation was found to be an effective, inexpensive, highly precise and safe way of treating periorbital syringomas. PMID:22762046

  9. A Complicated Postsurgical Echinococcal Cyst Treated with Radiofrequency Ablation

    SciTech Connect

    Thanos, L. Mylona, S.; Brontzakis, P.; Ptohis, N.; Karaliotas, K.

    2008-01-15

    Surgery of hydatid cysts is often complicated with intrabiliary rupture (IBR), which if not recognized may lead to biliary fistula with rather high rates of morbidity and mortality. We report our experience with the application of radiofrequency (RF) ablation for the treatment of an operated hepatic echinococcal cyst which was complicated with biliocystic communication and cysteocutaneous fistula with bile leakage. RF ablation was performed under CT guidance into the remaining cyst through the cutaneous fistula. Since ablation of the cyst and the fistula the patient has been asymptomatic.

  10. [Radiofrequency ablation of accessory pathways in pre-excitation syndrome].

    PubMed

    Pfeiffer, D; Tebbenjohanns, J; Jung, W; Manz, M; Lüderitz, B

    1993-04-16

    Various parameters relating to the radio-frequency ablation of accessory pathways were studied in 53 patients (27 males, 26 females: mean age 38.5 [14-64] years) with a history of paroxysmal tachycardia (over 1 month to 50 years), shown to be caused by an accessory pathway (Wolff-Parkinson-White syndrome). In all patients the following values were obtained: (1) number of procedures necessary to achieve permanent blockage of the accessory pathway (1-4); (2) duration of each procedure (45-420 min); (3) duration of fluoroscopy (5-102 min); (4) number of necessary radio-frequency applications (1-48); and (5) cumulative energy per procedure. To ablate left-lateral pathways (n = 10) required fewer procedures, shorter duration per procedure, shorter fluoroscopy time, fewer current applications and less total energy than coagulation of right-sided pathways (n = 10). Those various parameters were greatest for ablation of septal and para-septal pathways (n = 9). Pathways which conducted only retrogradely (n = 15) were more difficult to ablate than those with anterograde conduction (n = 38). There were two complications. In one case a tension pneumothorax occurred after faulty puncture of the subclavian vein; in the other, the left ventricle was perforated causing an acute tamponade which required pericardiocentesis with subsequent suture closure of the perforation. It is concluded that, in principle, all accessory pathways, regardless of their conduction potential and site, can be ablated by a radio-frequency current. PMID:8472633

  11. Bipolar Radiofrequency Neurotomy to Treat Neck and Back Pain in Patients with Automatic Implantable Cardioverter Defibrillator.

    PubMed

    Bautista, Alexander; Dadabayev, Alisher; Rosenquist, Ellen; Cheng, Jianguo

    2016-03-01

    We report 2 cases of successful treatment of neck and back pain with bipolar radiofrequency ablation (RFA) of the cervical and lumbar facet joints in patients with an automatic implantable cardioverter defibrillator (AICD).Two patients with complex cardiac histories and AICD devices were treated with bipolar RFA of the facet joints. One presented with axial neck pain and the other with axial back pain. The histories and physical examinations were consistent with facetogenic pain. Diagnostic medial branch block resulted in more than 70% pain relief lasting for several days, allowing patients to perform routine daily activities without significant pain. However, we were concerned about the use of conventional RFA of the medial branches of nerves for the fear of interference with the function of AICD by the RF currents and energy. We took advantage of the localized and limited current of bipolar RFA to perform this procedure for the cervical or lumbar facet joints avoiding any interference with the function of AICD. The procedures provided long-term pain relief to the patients, and marked improvement in their functional status without any evident complications related to the function of their AICD.This case report describes the safe and successful completion of bipolar RFA of the medial branch nerves to treat cervical and lumbar facetogenic pain in patients with AICD. This modality of treatment may be considered in patients with AICD. We are finding it to be increasingly common that patients who present with chronic neck and back pain have AICDs in place. PMID:27008309

  12. Novel Percutaneous Radiofrequency Ablation of Portal Vein Tumor Thrombus: Safety and Feasibility

    SciTech Connect

    Mizandari, Malkhaz; Ao, Guokun; Zhang Yaojun; Feng Xi; Shen Qiang; Chen Minshan; Lau, Wan Yee; Nicholls, Joanna; Jiao Long; Habib, Nagy

    2013-02-15

    We report our experience of the safety of partial recanalization of the portal vein using a novel endovascular radiofrequency (RF) catheter for portal vein tumor thrombosis. Six patients with liver cancer and tumor thrombus in the portal vein underwent percutaneous intravascular radiofrequency ablation (RFA) using an endovascular bipolar RF device. A 0.035-inch guidewire was introduced into a tributary of the portal vein and through which a 5G guide catheter was introduced into the main portal vein. After manipulation of the guide catheter over the thrombus under digital subtraction angiography, the endovascular RF device was inserted and activated around the thrombus. There were no observed technique specific complications, such as hemorrhage, vessel perforation, or infection. Post-RFA portography showed partial recanalization of portal vein. RFA of portal vein tumor thrombus in patients with hepatocellular carcinoma is technically feasible and warrants further investigation to assess efficacy compared with current recanalization techniques.

  13. Cardiac Radiofrequency Ablation: A Clinical Update for Nurses.

    PubMed

    Shoulders, Bridget; Mauriello, Jillian; Shellman, Tamika; Follett, Corrinne

    2016-01-01

    The field of electrophysiology (EP) has rapidly evolved from a focus on diagnostic procedures to an emphasis on interventions. Many cardiac arrhythmias traditionally treated with antiarrhythmic agents, cardioversion, or cardiac surgery are now routinely cured with cardiac ablation. To optimally manage the care of cardiac ablation patients, it is essential that nurses have an understanding of the EP procedures and related nursing implications. There are extensive evidence-based resources available in the medical literature; however, there are limited publications geared toward nurses caring for cardiac ablation patients.This article provides an overview of EP diagnostic and cardiac radio-frequency ablation procedures for select atrial and ventricular tachyarrhythmias. Evidence-based nursing practices related to postprocedure care will be addressed. The objective of this article is to increase nurses' knowledge of common cardiac ablation procedures and the nursing management of the patient postprocedure. PMID:27487751

  14. Radiofrequency Ablation of Osteoid Osteoma: Initial Experience with a New Monopolar Ablation Device

    SciTech Connect

    Mahnken, Andreas H. Bruners, Philipp; Delbrueck, Heide; Guenther, Rolf W.

    2011-06-15

    The purpose of this article is to report our initial experience with the 'off-label' use of a new monopolar radiofrequency (RF) probe for percutaneous ablation of osteoid osteomas. Seventeen patients (12 male and 5 female, mean age 24.8 [range 9-49]) with osteoid osteoma were treated by computed tomography (CT)-guided RF ablation (RFA). All procedures were performed with the patient under general aesthesia. After localization of the nidus, a 13G hollow drill was introduced into the nidus through a 7F introducer sheath. A monopolar 16.5G RF probe with a 9-mm active tip (Soloist; Boston Scientific, Natick, MA) was inserted through the introducer sheath and connected to the RF generator. Energy application was started at 2 W and subsequently increased every 2 min by 1 W to a maximum of 8 W. The procedure ended if impedance increased by 500 Ohm-Sign . Mean duration of energy deposition was 14.2 {+-} 3.3 min. Fourteen of 17 patients (82%) were free of symptoms at 29.9 {+-} 14.8 (range 4 to 47) months of follow-up. The primary and secondary success rates were 83% and 100%, respectively. In 3 patients, recurrence of pain at 6 (n = 1) and 15 (n = 2) months after the initial procedure was successfully treated by reablation. There were no complications. Monopolar RFA using the Soloist probe is effective and safe for the treatment of osteoid osteoma. It results in comparable success rates as other monopolar or bipolar RF systems in the treatment of osteoid osteoma.

  15. Radiofrequency ablation of osteoid osteoma: initial experience with a new monopolar ablation device.

    PubMed

    Mahnken, Andreas H; Bruners, Philipp; Delbrück, Heide; Günther, Rolf W

    2011-06-01

    The purpose of this article is to report our initial experience with the "off-label" use of a new monopolar radiofrequency (RF) probe for percutaneous ablation of osteoid osteomas. Seventeen patients (12 male and 5 female, mean age 24.8 [range 9-49]) with osteoid osteoma were treated by computed tomography (CT)-guided RF ablation (RFA). All procedures were performed with the patient under general aesthesia. After localization of the nidus, a 13G hollow drill was introduced into the nidus through a 7F introducer sheath. A monopolar 16.5G RF probe with a 9-mm active tip (Soloist; Boston Scientific, Natick, MA) was inserted through the introducer sheath and connected to the RF generator. Energy application was started at 2 W and subsequently increased every 2 min by 1 W to a maximum of 8 W. The procedure ended if impedance increased by 500 Ω. Mean duration of energy deposition was 14.2±3.3 min. Fourteen of 17 patients (82%) were free of symptoms at 29.9±14.8 (range 4 to 47) months of follow-up. The primary and secondary success rates were 83% and 100%, respectively. In 3 patients, recurrence of pain at 6 (n=1) and 15 (n=2) months after the initial procedure was successfully treated by reablation. There were no complications. Monopolar RFA using the Soloist probe is effective and safe for the treatment of osteoid osteoma. It results in comparable success rates as other monopolar or bipolar RF systems in the treatment of osteoid osteoma. PMID:20490491

  16. Polarimetric assessment of healthy and radiofrequency ablated porcine myocardial tissue.

    PubMed

    Ahmad, Iftikhar; Gribble, Adam; Ikram, Masroor; Pop, Mihaela; Vitkin, Alex

    2016-07-01

    Radiofrequency (RF) ablation offers a potential treatment for cardiac arrhythmia, where properly titrated energy delivered at critical sites can destroy arrhythmogenic foci. The resulting ablation lesion typically consists of a core (coagulative necrosis) surrounded by a rim of mixed viable and non-viable cells. The extent of the RF lesion is difficult to delineate with current imaging techniques. Here, we explore polarization signatures of ten ex-vivo samples from untreated (n = 5) and RF ablated porcine hearts (n = 5), in backscattered geometry through Mueller matrix polarimetry. Significant differences (p < 0.01) in depolarization, ΔT , were observed between the healthy, RF ablated and rim regions. Linear retardance, δ, was significantly lower in the core and rim regions compared to healthy regions (p < 0.05). The results demonstrate a novel application of polarimetry, namely the characterization of RF ablation extent in myocardium, including the visualization of the important lesion rim region. White light photo (top) of porcine myocardium tissue with radiofrequency ablation lesion and corresponding depolarization map (bottom). Depolarization is useful for visualizing the lesion core and rim. PMID:26394151

  17. [Treatment of atrial fibrillation using maze procedure by radiofrequency ablation].

    PubMed

    Cai, Z; Sun, G; Du, R

    1997-12-01

    From May 1994 to May 1996, 20 cases of atrial fibrillation were treated by means of Maze procedure by radiofrequenncy ablation, at the same time 19 cases of these patients were complicated with rheumatic heart valve disease and valve replacement operations were perfomned, in the other case atrial septal defect was repaired. Yoshio Kosakai's operation route was adopted in radiofrequency ablation procedure. After operation 16 patients of atrial fibrillation resumed sinus rhythm (80%), in 4 casess of atrial fibrillation sinus rhythm was unsuccessfully restored, two patients remained atrial fibrillation, one patient was of atrial flutter, the other was of nodal rhythm. Short time was needed in radiofrequency ablation Maze procedure, average time increase of aortic clamping was 20.5 minutes, and there was no danger of hemorrhage related to this kinds of Maze procedure. During 7-10 days after operation, there appeared superventricular arrhythmia which might be related to ill-distribution of radiofrequency ablation, and interference of atrial electric activity. PMID:10677989

  18. Delayed Development of Pneumothorax After Pulmonary Radiofrequency Ablation

    SciTech Connect

    Clasen, Stephan; Kettenbach, Joachim; Kosan, Bora; Aebert, Hermann; Schernthaner, Melanie; Kroeber, Stefan-Martin; Boemches, Andrea; Claussen, Claus D.; Pereira, Philippe L.

    2009-05-15

    Acute pneumothorax is a frequent complication after percutaneous pulmonary radiofrequency (RF) ablation. In this study we present three cases showing delayed development of pneumothorax after pulmonary RF ablation in 34 patients. Our purpose is to draw attention to this delayed complication and to propose a possible approach to avoid this major complication. These three cases occurred subsequent to 44 CT-guided pulmonary RF ablation procedures (6.8%) using either internally cooled or multitined expandable RF electrodes. In two patients, the pneumothorax, being initially absent at the end of the intervention, developed without symptoms. One of these patients required chest drain placement 32 h after RF ablation, and in the second patient therapy remained conservative. In the third patient, a slight pneumothorax at the end of the intervention gradually increased and led into tension pneumothorax 5 days after ablation procedure. Underlying bronchopleural fistula along the coagulated former electrode track was diagnosed in two patients. In conclusion, delayed development of pneumothorax after pulmonary RF ablation can occur and is probably due to underlying bronchopleural fistula, potentially leading to tension pneumothorax. Patients and interventionalists should be prepared for delayed onset of this complication, and extensive track ablation following pulmonary RF ablation should be avoided.

  19. Radiofrequency ablation for neuroendocrine liver metastases: a systematic review.

    PubMed

    Mohan, Helen; Nicholson, Patrick; Winter, Des C; O'Shea, Donal; O'Toole, Dermot; Geoghegan, Justin; Maguire, Donal; Hoti, Emir; Traynor, Oscar; Cantwell, Colin P

    2015-07-01

    To determine the efficacy of radiofrequency (RF) ablation in neuroendocrine tumor (NET) liver metastases. A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eight studies were included (N = 301). Twenty-six percent of RF ablation procedures were percutaneous (n = 156), with the remainder conducted at surgery. Forty-eight percent of patients had a concomitant liver resection. Fifty-four percent of patients presented with symptoms, with 92% reporting symptom improvement following RF ablation (alone or in combination with surgery). The median duration of symptom improvement was 14-27 months. However, recurrence was common (63%-87%). RF ablation can provide symptomatic relief in NET liver metastases alone or in combination with surgery. PMID:25840836

  20. Diaphragmatic Hernia After Radiofrequency Ablation for Hepatocellular Carcinoma

    SciTech Connect

    Yamagami, Takuji Yoshimatsu, Rika; Matsushima, Shigenori; Tanaka, Osamu; Miura, Hiroshi; Nishimura, Tsunehiko

    2011-02-15

    We describe a 71-year-old woman with a hepatocellular carcinoma who underwent percutaneous radiofrequency ablation (RF) with a single internally cooled electrode under computed tomography (CT) fluoroscopic guidance. Nine months after the procedure, CT images showed herniation of the large intestine into the right pleural cavity. To our knowledge this complication of RF performed with a single internally cooled electrode under CT guidance has not been previously reported.

  1. Endometrial ablation

    MedlinePlus

    Hysteroscopy-endometrial ablation; Laser thermal ablation; Endometrial ablation-radiofrequency; Endometrial ablation-thermal balloon ablation; Rollerball ablation; Hydrothermal ablation; Novasure ablation

  2. A rare complication following radiofrequency ablation.

    PubMed

    Rajakulasingam, Ramyah; Francis, Rohin; Ghuran, Azad

    2013-01-01

    Atrial-oesophageal fistula (AOF) formation is a rare but often fatal complication post radio frequency ablation (RFA). Mortality ranges from 67% to 100%, with a rapid progression from symptom onset to death. We report a case of a healthy man in his early 40s who presented with a Glasgow Coma Scale  of 5/15, clinical evidence of sepsis and Streptococcus viridans bacteraemia, 14 days following uncomplicated RFA for atrial fibrillation. Establishing a diagnosis of AOF can be difficult, as patients may have bacteraemia, but are consequently misdiagnosed with infective endocarditis, as in this case. One should have a high-index of suspicion for AOF in patients presenting with the aforementioned constellation of symptoms following ablation. There are no established predictors of mortality, but prompt detection, emergent operative intervention and prolonged antibiotic therapy are vital for survival. PMID:23420721

  3. Radiofrequency Ablation of Lung Malignancies: Where Do We Stand?

    SciTech Connect

    Lencioni, Riccardo Crocetti, Laura; Cioni, Roberto; Mussi, Alfredo; Fontanini, Gabriella; Ambrogi, Marcello; Franchini, Chiara; Cioni, Dania; Fanucchi, Olivia; Gemignani, Raffaello; Baldassarri, Rubia; Angeletti, Carlo Alberto; Bartolozzi, Carlo

    2004-11-15

    Percutaneous radiofrequency (RF) ablation is a minimally invasive technique used to treat solid tumors. Because of its ability to produce large volumes of coagulation necrosis in a controlled fashion, this technique has gained acceptance as a viable therapeutic option for unresectable liver malignancies. Recently, investigation has been focused on the clinical application of RF ablation in the treatment of lung malignancies. In theory, lung tumors are well suited to RF ablation because the surrounding air in adjacent normal parenchyma provides an insulating effect, thus facilitating energy concentration within the tumor tissue. Experimental studies in rabbits have confirmed that lung RF ablation can be safely and effectively performed via a percutaneous, transthoracic approach, and have prompted the start of clinical investigation. Pilot clinical studies have shown that RF ablation enables successful treatment of relatively small lung malignancies with a high rate of complete response and acceptable morbidity, and have suggested that the technique could represent a viable alternate or complementary treatment method for patients with non-small cell lung cancer or lung metastases of favorable histotypes who are not candidates for surgical resection. This article gives an overview of lung RF ablation, discussing experimental animal findings, rationale for clinical application, technique and methodology, clinical results, and complications.

  4. Percutaneous radiofrequency ablation of spinal osteoid osteoma under CT guidance

    PubMed Central

    Morassi, L G; Kokkinis, K; Karargyris, O; Vlachou, I; Kalokairinou, K; Pneumaticos, S G

    2014-01-01

    Objective: Osteoid osteoma (OO) accounts for approximately 10–12% of all benign bone tumours and 3% of all bone tumours. Spinal involvement appears in 10–25% of all cases. The purpose of this study was to evaluate the safety and efficacy of CT-guided radiofrequency (RF) ablation in the treatment of spinal OOs and report our experience. Methods: 13 patients suffering from spinal OO and treated at the authors' institution using CT-guided RF ablation were retrospectively evaluated. The RF probe was introduced through a 11-G Jamshidi® needle, and the lesion was heated at 90 °C for 6 min. Results: All procedures were considered technically successful as the correct positioning of the probe was proven by CT. 11 of the 13 patients reported pain relief after RF ablation. In two cases, RF ablation was repeated 1 month after the first procedure. Pain relief was achieved in both cases after the second procedure. No recurrence was reported throughout the follow-up. No complications like skin burn, soft-tissue haematoma, infection, vessel damage or neurological deficit were reported. Conclusion: This study demonstrates that CT-guided percutaneous RF ablation is a safe and effective method for the treatment of spinal OOs. Advances in knowledge: The data of this study support the efficacy and safety of the recently applied CT-guided percutaneous RF ablation technique for the treatment of spinal OOs. PMID:24712322

  5. Continuous Cavitation Designed for Enhancing Radiofrequency Ablation via a Special Radiofrequency Solidoid Vaporization Process.

    PubMed

    Zhang, Kun; Li, Pei; Chen, Hangrong; Bo, Xiaowan; Li, Xiaolong; Xu, Huixiong

    2016-02-23

    Lowering power output and radiation time during radiofrequency (RF) ablation is still a challenge. Although it is documented that metal-based magnetothermal conversion and microbubbles-based inertial cavitation have been tried to overcome above issues, disputed toxicity and poor magnetothermal conversion efficiency for metal-based nanoparticles and violent but transient cavitation for microbubbles are inappropriate for enhancing RF ablation. In this report, a strategy, i.e., continuous cavitation, has been proposed, and solid menthol-encapsulated poly lactide-glycolide acid (PLGA) nanocapsules have been constructed, as a proof of concept, to validate the role of such a continuous cavitation principle in continuously enhancing RF ablation. The synthesized PLGA-based nanocapsules can respond to RF to generate menthol bubbles via distinctive radiofrequency solidoid vaporization (RSV) process, meanwhile significantly enhance ultrasound imaging for HeLa solid tumor, and further facilitate RF ablation via the continuous cavitation, as systematically demonstrated both in vitro and in vivo. Importantly, this RSV strategy can overcome drawbacks and limitations of acoustic droplet vaporization (ADV) and optical droplet vaporization (ODV), and will probably find broad applications in further cancer theranostics. PMID:26800221

  6. Mathematical Modeling of Radiofrequency Ablation for Varicose Veins

    PubMed Central

    Choi, Sun Young; Kwak, Byung Kook

    2014-01-01

    We present a three-dimensional mathematical model for the study of radiofrequency ablation (RFA) with blood flow for varicose vein. The model designed to analyze temperature distribution heated by radiofrequency energy and cooled by blood flow includes a cylindrically symmetric blood vessel with a homogeneous vein wall. The simulated blood velocity conditions are U = 0, 1, 2.5, 5, 10, 20, and 40 mm/s. The lower the blood velocity, the higher the temperature in the vein wall and the greater the tissue damage. The region that is influenced by temperature in the case of the stagnant flow occupies approximately 28.5% of the whole geometry, while the region that is influenced by temperature in the case of continuously moving electrode against the flow direction is about 50%. The generated RF energy induces a temperature rise of the blood in the lumen and leads to an occlusion of the blood vessel. The result of the study demonstrated that higher blood velocity led to smaller thermal region and lower ablation efficiency. Since the peak temperature along the venous wall depends on the blood velocity and pullback velocity, the temperature distribution in the model influences ablation efficiency. The vein wall absorbs more energy in the low pullback velocity than in the high one. PMID:25587351

  7. Catheter ablation of atrioventricular accessory pathways by radiofrequency current.

    PubMed

    Wang, L; Hu, D; Ding, Y

    1993-12-15

    Tachycardias mediated by atrioventricular accessory pathways, which are refractory to antiarrhythmic drug therapy have been treated both by surgery and by catheter ablation with high energy direct current shock. These procedures have variable success rates and substantial associated morbidity and mortality. Radiofrequency ablation, a newer, low-energy technique is potentially safer and more effective. Of 110 patients with 117 accessory pathways, 101 were located on the left side and 16 on the right. Accessory pathway conduction was abolished permanently in 101 (91.8%) patients. VA conduction dissociation and VA decremental conduction were found in 88 and 13 successful patients, respectively. Four (3.9%) patients with decremental VA conduction suffered arrhythmia recurrence after a mean of 8 months follow-up. Complications developed in two patients including right femoral vein thrombosis and left ventricular insufficiency. There were no deaths from the procedure. We conclude that radiofrequency current ablation is a safe and effective interventional modality for patients with symptomatic tachycardias mediated by atrioventricular accessory pathways. PMID:8112920

  8. Incidence and Cause of Hypertension During Adrenal Radiofrequency Ablation

    SciTech Connect

    Yamakado, Koichiro Takaki, Haruyuki; Yamada, Tomomi; Yamanaka, Takashi; Uraki, Junji; Kashima, Masataka; Nakatsuka, Atsuhiro; Takeda, Kan

    2012-12-15

    Purpose: To evaluate the incidence and cause of hypertension prospectively during adrenal radiofrequency ablation (RFA). Methods: For this study, approved by our institutional review board, written informed consent was obtained from all patients. Patients who received RFA for adrenal tumors (adrenal ablation) and other abdominal tumors (nonadrenal ablation) were included in this prospective study. Blood pressure was monitored during RFA. Serum adrenal hormone levels including epinephrine, norepinephrine, dopamine, and cortisol levels were measured before and during RFA. The respective incidences of procedural hypertension (systolic blood pressure >200 mmHg) of the two patient groups were compared. Factors correlating with procedural systolic blood pressure were evaluated by regression analysis.ResultsNine patients underwent adrenal RFA and another 9 patients liver (n = 5) and renal (n = 4) RFA. Asymptomatic procedural hypertension that returned to the baseline by injecting calcium blocker was found in 7 (38.9%) of 18 patients. The incidence of procedural hypertension was significantly higher in the adrenal ablation group (66.7%, 6/9) than in the nonadrenal ablation group (11.1%, 1/9, P < 0.0498). Procedural systolic blood pressure was significantly correlated with serum epinephrine (R{sup 2} = 0.68, P < 0.0001) and norepinephrine (R{sup 2} = 0.72, P < 0.0001) levels during RFA. The other adrenal hormones did not show correlation with procedural systolic blood pressure. Conclusion: Hypertension occurs frequently during adrenal RFA because of the release of catecholamine.

  9. Radiofrequency Ablation Treatment in Proximity to the Gallbladder Without Subsequent Acute Cholecystitis

    SciTech Connect

    Patti, Jay W.; Neeman, Ziv Wood, Bradford J.

    2003-08-15

    Initial reports have suggested that proximity of liver tumors to the gallbladder may increase the risk for cholecystitis after radiofrequency ablation. A colon adenocarcinoma metastasis to the liver in contact with the gallbladder was successfully treated with radiofrequency ablation without subsequent cholecystitis.

  10. Percutaneous radiofrequency ablation of primary intraosseous spinal glomus tumor.

    PubMed

    Becce, Fabio; Richarme, Delphine; Letovanec, Igor; Gilgien, Willy; Theumann, Nicolas

    2012-04-01

    The glomus tumor is a rare, benign, but painful vascular neoplasm arising from the neuromyoarterial glomus. Primary intraosseous glomus tumor is even rarer, with only about 20 cases reported in the literature so far, 5 of which involved the spine. Surgical resection is currently considered the treatment of choice. We herewith present an uncommon case of primary intraosseous spinal glomus tumor involving the right pedicle of the eleventh thoracic vertebra (T11). To our knowledge, this is the first case of primary intraosseous spinal glomus tumor successfully treated by percutaneous CT-guided radiofrequency ablation (RFA). PMID:22072240

  11. Percutaneous radiofrequency ablation: minimally invasive therapy for renal tumors.

    PubMed

    Ahrar, Kamran; Wallace, Michael J; Matin, Surena F

    2006-12-01

    Currently, up to 60% of renal tumors are detected incidentally by abdominal imaging. Most of these tumors are small and localized to the kidney. Owing to the shift to lower stage at diagnosis, radical nephrectomy has fallen out of favor and has been replaced by nephron-sparing surgery. Currently, partial nephrectomy is the treatment of choice for patients with small renal tumors. As the trend towards less invasive therapy continues, laparoscopic and percutaneous ablation techniques have gained popularity for the treatment of renal tumors in patients who are high-risk surgical candidates, or have a solitary kidney, limited renal function or multifocal disease. Percutaneous radiofrequency ablation is a safe, minimally invasive treatment option for those patients. PMID:17181487

  12. Bronchopleural Fistula After Radiofrequency Ablation of Lung Tumours

    SciTech Connect

    Cannella, Mathieu; Cornelis, Francois; Descat, Edouard; Ferron, Stephane; Carteret, Thibault; Castagnede, Hugues; Palussiere, Jean

    2011-02-15

    The present article describes two cases of bronchopleural fistula (BPF) occurring after radiofrequency ablation of lung tumors. Both procedures were carried out using expandable multitined electrodes, with no coagulation of the needle track. After both ablations, ground-glass opacities encompassed the nodules and abutted the visceral pleura. The first patient had a delayed pneumothorax, and the second had a recurrent pneumothorax. Both cases of BPF were diagnosed on follow-up computed tomography chest scans (i.e., visibility of a distinct channel between the lung or a peripheral bronchus and the pleura) and were successfully treated with chest tubes alone. Our goal is to highlight the fact that BPF can occur without needle-track coagulation and to suggest that minimally invasive treatment is sufficient to cure BPFs of this specific origin.

  13. Laparoscopic Ultrasound-Guided Radiofrequency Ablation of Uterine Fibroids

    SciTech Connect

    Milic, Andrea; Asch, Murray R. Hawrylyshyn, Peter A.; Allen, Lisa M.; Colgan, Terence J.; Kachura, John R.; Hayeems, Eran B.

    2006-08-15

    Four patients with symptomatic uterine fibroids measuring less than 6 cm underwent laparoscopic ultrasound-guided radiofrequency ablation (RFA) using multiprobe-array electrodes. Follow-up of the treated fibroids was performed with gadolinium-enhanced magnetic resonance imaging (MRI) and patients' symptoms were assessed by telephone interviews. The procedure was initially technically successful in 3 of the 4 patients and MRI studies at 1 month demonstrated complete fibroid ablation. Symptom improvement, including a decrease in menstrual bleeding and pain, was achieved in 2 patients at 3 months. At 7 months, 1 of these 2 patients experienced symptom worsening which correlated with recurrent fibroid on MRI. The third, initially technically successfully treated patient did not experience any symptom relief after the procedure and was ultimately diagnosed with adenomyosis. Our preliminary results suggest that RFA is a technically feasible treatment for symptomatic uterine fibroids in appropriately selected patients.

  14. Ultrasonography guided percutaneous radiofrequency ablation for hepatic cavernous hemangioma

    PubMed Central

    Cui, Yan; Zhou, Li-Yan; Dong, Man-Ku; Wang, Ping; Ji, Min; Li, Xiao-Ou; Chen, Chang-Wei; Liu, Zi-Pei; Xu, Yong-Jie; Zhang, Hong-Wen

    2003-01-01

    AIM: Hepatic cavernous hemangioma (HCH) is the most common benign tumor of the liver and its management is still controversial. Recent success in situ radiofrequency ablation of hepatic malignancies has led us to consider using this technique in patients with HCH. This study was to assess the efficacy, safety, and complications of percutaneous radiofrequency ablation (PRFA) under ultrasonography guidance in patients with HCH. METHODS: Twelve patients (four men and eight women, age ranged 33-56 years, mean age was 41.7 years) with 15 hepatic cavernous hemangiomas (2.5 cm to 9.5 cm) were treated using the RF-2000 generator and 10-needle LeVeen electrode percutaneously guided by B-ultrasound. Lesions larger than 3 cm were treated by multiple overlapping ablations that encompass the entire lesion as well as a rim of normal liver tissue (approximately 0.5 cm). RESULTS: All the patients who received PRFA therapy had no severe pain, bleeding or bile leakage during and after the procedures. Nine to 34 months’ follow-up (mean, 21 months) by ultrasound and/or spiral CT scan demonstrated that the ablated lesions in this group were shrunk remarkably, and the shrunken range was 38%-79% (mean, 67% per 21 months). The contrast enhancement was disappeared within the tumor or at its periphery in all cases on spiral CT scans obtained 3 to 6 months after treatment. CONCLUSION: The results of this study suggest that PRFA therapy is a mini-invasive, simple, safe, and effective method for the treatment of selected patients with HCH. PMID:12970923

  15. Use of a vascular sheath for introduction of radiofrequency ablation probe during radiofrequency ablation of osteoid osteoma

    PubMed Central

    Ahmed, Munawwar; Keshava, Shyamkumar N; Moses, Vinu; Mammen, Suraj; Jacob, Korula Mani; Madhuri, Vrisha

    2015-01-01

    Radiofrequency ablation (RFA) has now become a preferred treatment option for osteoid osteoma. Accurate placement of RFA probe into the nidus of osteoid osteoma is important for good clinical outcome. Various methods and techniques have been described in the literature available. We describe the technique of using a vascular access sheath for introduction of RFA probe after bone drilling, which prevents loss of access to drill track and also serves as a pathway for accurate placement of RFA probe, thereby reducing the risk of damage to the RFA probe tip itself and the surrounding soft tissue. PMID:26752816

  16. Catheter ablation of atrial fibrillation: Radiofrequency catheter ablation for redo procedures after cryoablation

    PubMed Central

    Kettering, Klaus; Gramley, Felix

    2013-01-01

    AIM: To evaluate the effectiveness of two different strategies using radiofrequency catheter ablation for redo procedures after cryoablation of atrial fibrillation. METHODS: Thirty patients (paroxysmal atrial fibrillation: 22 patients, persistent atrial fibrillation: 8 patients) had to undergo a redo procedure after initially successful circumferential pulmonary vein (PV) isolation with the cryoballoon technique (Arctic Front Balloon, CryoCath Technologies/Medtronic). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (CARTO; Biosense Webster) depending on the intra-procedural findings. After discharge, patients were scheduled for repeated visits at the arrhythmia clinic. A 7-day Holter monitoring was performed at 3, 12 and 24 mo after the ablation procedure. RESULTS: During the redo procedure, a mean number of 2.9 re-conducting pulmonary veins (SD ± 1.0 PVs) were detected (using a circular mapping catheter). In 20 patients, a segmental approach was sufficient to eliminate the residual pulmonary vein conduction because there were only a few recovered pulmonary vein fibres. In the remaining 10 patients, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction. All recovered pulmonary veins could be isolated successfully again. At 2-year follow-up, 73.3% of all patients were free from an arrhythmia recurrence (22/30). There were no major complications. CONCLUSION: In patients with an initial circumferential pulmonary vein isolation using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation. PMID:24009817

  17. Use of Semiflexible Applicators for Radiofrequency Ablation of Liver Tumors

    SciTech Connect

    Gaffke, G. Gebauer, B.; Knollmann, F.D.; Helmberger, T.; Ricke, J.; Oettle, H.; Felix, R.; Stroszczynski, C.

    2006-04-15

    Purpose. To evaluate the feasibility and potential advantages of the radiofrequency ablation of liver tumors using new MRI-compatible semiflexible applicators in a closed-bore high-field MRI scanner. Methods. We treated 8 patients with 12 malignant liver tumors of different origin (5 colorectal carcinoma, 2 cholangiocellular carcinoma, 1 breast cancer) under MRI guidance. Radiofrequency ablation (RFA) was performed using 5 cm Rita Starburst Semi-Flex applicators (Rita Medical Systems, Milwaukee, WI, USA) which are suitable for MR- and CT-guided interventions and a 150 W RF generator. All interventions were performed in a closed-bore 1.5 T high-field MRI scanner for MRI-guided RFA using fast T1-weighted gradient echo sequences and T2-weighted ultra-turbo spin echo sequences. Control and follow-up MRI examinations were performed on the next day, at 6 weeks, and every 3 months after RFA. Control MRI were performed as double-contrast MRI examinations (enhancement with iron oxide and gadopentetate dimeglumine). All interventions were performed with the patient under local anesthesia and analgo-sedation. Results. The mean diameter of the treated hepatic tumors was 2.4 cm ({+-}0.6 cm, range 1.0-3.2 cm). The mean diameter of induced necrosis was 3.1 cm ({+-}0.4 cm). We achieved complete ablation in all patients. Follow-up examinations over a duration of 7 months ({+-}1.3 months, range 4-9 month) showed a local control rate of 100% in this group of patients. All interventions were performed without major complications; only 2 subcapsular hematomas were documented. Conclusion. RFA of liver tumors using semiflexible applicators in closed-bore 1.5 T scanner systems is feasible. These applicators might simplify the RFA of liver tumors under MRI control. The stiff distal part of the applicator facilitates its repositioning.

  18. Radiofrequency catheter septal ablation for hypertrophic obstructive cardiomyopathy in children

    PubMed Central

    Emmel, M.; Sreeram, N.

    2005-01-01

    Background The definitive therapeutic options for symptomatic obstructive cardiomyopathy in childhood are restricted. At present, extensive surgical myectomy is the only procedure that is of proven benefit. Patients and Methods Three patients, aged 5, 11 and 17 years, respectively, with progressive hypertrophic obstructive cardiomyopathy and increasing symptoms were considered for radiofrequency catheter septal ablation. The peak Doppler gradient recorded on several occasions ranged between 50 to 90mmHg. Via a femoral arterial approach, the His bundle was initially plotted and marked using the LocaLisa navigation system. Subsequently, using a cooled tip catheter a series of lesions were placed in the hypertrophied septum, taking care to stay away from the His bundle. A total of 17, 50 and 45 lesions were applied in the three patients. In one case, the procedure was complicated by two episodes of ventricular fibrillation requiring DC cardioversion but without any neurological sequelae. Results The preablation peak-to-peak gradient between left ventricle and aorta was 50 mmHg, 60 mmHg and 60 mmHg, respectively, and remained unchanged immediately after the procedure. All patients were discharged from hospital 48 hours later. Serial measurement of serum troponin T and CK-MB isoenzyme confirmed significant myocardial necrosis. Follow-up echocardiography both at seven days and at six weeks postablation confirmed a beneficial haemodynamic result, with reduction of left ventricular outflow obstruction and relief of symptoms. Conclusion In young children, in whom alcohol-induced septal ablation is not an option, radiofrequency catheter ablation offers an alternative to surgery, with the benefits of repeatability and a lower risk of procedure-related permanent AV block. ImagesFigure 1Figure 2Figure 3Figure 4 PMID:25696442

  19. Treatment of Acne Scars of Skin Types II to V by Sublative Fractional Bipolar Radiofrequency and Bipolar Radiofrequency Combined with Diode Laser

    PubMed Central

    Garretson, Cara Beth

    2011-01-01

    Objective: This study evaluated the safety and efficacy of sublative fractional bipolar radiofrequency and bipolar radio frequency combined with diode laser for the treatment of both superficial and deep acne scars in patients with skin types II to V. Design: Prospective, single-center study. Subjects received up to five treatments with sublative fractional bipolar radiofrequency and bipolar radiofrequency combined with diode laser. Treatments were directed to at least two facial (forehead, perioral, cheeks) and/or neck areas with acne scars at four-week intervals. Treatment parameters on each subject were based on skin type and on skin responses to test spots on the target area just before treatment. Setting: Physician office. Participants: Subjects (n=20, aged 40.7±10.5 years [mean ± SD], skin types II–V) with acne scars and without acne lesions enrolled in this prospective study. Measurements: Results were evaluated just before each treatment and at four and 12 weeks after the final treatment using the Goodman Scar Scale, a quantitative method of evaluating scars that attempts to reduce grading subjectivity, as well as by patient satisfaction. Results: Acne scars improved significantly one month after three treatments and improvement persisted for at least 12 weeks after the fifth treatment. Improvement was not affected by skin type. Adverse effects were limited to transient erythema and edema. Conclusion: The combination of diode laser and bipolar radiofrequency energy device in addition to fractionated sublative radiofrequency is a safe and statistically significantly effective combined modality for the treatment of both superficial and deep acne scars in patients with skin types II to V with minimal downtime and no significant side effects. PMID:22010052

  20. Lung Tumor Radiofrequency Ablation: Where Do We Stand?

    SciTech Connect

    Baere, Thierry de

    2011-04-15

    Today, radiofrequency ablation (RFA) of primary and metastatic lung tumor is increasingly used. Because RFA is most often used with curative intent, preablation workup must be a preoperative workup. General anesthesia provides higher feasibility than conscious sedation. The electrode positioning must be performed under computed tomography for sake of accuracy. The delivery of RFA must be adapted to tumor location, with different impedances used when treating tumors with or without pleural contact. The estimated rate of incomplete local treatment at 18 months was 7% (95% confidence interval, 3-14) per tumor, with incomplete treatment depicted at 4 months (n = 1), 6 months (n = 2), 9 months (n = 2), and 12 months (n = 2). Overall survival and lung disease-free survival at 18 months were, respectively, 71 and 34%. Size is a key point for tumor selection because large size is predictive of incomplete local treatment and poor survival. The ratio of ablation volume relative to tumor volume is predictive of complete ablation. Follow-up computed tomography that relies on the size of the ablation zone demonstrates the presence of incomplete ablation. Positron emission tomography might be an interesting option. Chest tube placement for pneumothorax is reported in 8 to 12%. Alveolar hemorrhage and postprocedure hemoptysis occurred in approximately 10% of procedures and rarely required specific treatment. Death was mostly related to single-lung patients and hilar tumors. No modification of forced expiratory volume in the first second between pre- and post-RFA at 2 months was found. RFA in the lung provides a high local efficacy rate. The use of RFA as a palliative tool in combination with chemotherapy remains to be explored.

  1. Software-assisted post-interventional assessment of radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Rieder, Christian; Geisler, Benjamin; Bruners, Philipp; Isfort, Peter; Na, Hong-Sik; Mahnken, Andreas H.; Hahn, Horst K.

    2014-03-01

    Radiofrequency ablation (RFA) is becoming a standard procedure for minimally invasive tumor treatment in clinical practice. Due to its common technical procedure, low complication rate, and low cost, RFA has become an alternative to surgical resection in the liver. To evaluate the therapy success of RFA, thorough follow-up imaging is essential. Conventionally, shape, size, and position of tumor and coagulation are visually compared in a side-by-side manner using pre- and post-interventional images. To objectify the verification of the treatment success, a novel software assistant allowing for fast and accurate comparison of tumor and coagulation is proposed. In this work, the clinical value of the proposed assessment software is evaluated. In a retrospective clinical study, 39 cases of hepatic tumor ablation are evaluated using the prototype software and conventional image comparison by four radiologists with different levels of experience. The cases are randomized and evaluated in two sessions to avoid any recall-bias. Self-confidence of correct diagnosis (local recurrence vs. no local recurrence) on a six-point scale is given for each case by the radiologists. Sensitivity, specificity, positive and negative predictive values as well as receiver operating curves are calculated for both methods. It is shown that the software-assisted method allows physicians to correctly identify local tumor recurrence with a higher percentage than the conventional method (sensitivity: 0.6 vs. 0.35), whereas the percentage of correctly identified successful ablations is slightly reduced (specificity: 0.83 vs. 0.89).

  2. [RADIOFREQUENCY ABLATION FOR THE TREATMENT OF VARICOSE VEINS].

    PubMed

    Sugiyama, Satoru; Miyade, Yoshio; Inaki, Yasuhiko

    2015-05-01

    Significant advances in the endovenous technique for treating incompetent saphenous veins could change the surgical strategy in patients with varicose veins. Radiofrequency ablation (RFA) was approved as a new technique for the treatment of varicose veins in Japan in June 2014. In RFA, the ablation temperature is controlled by a sensor at the upper end of the catheter. The vein wall is heated with stable conductive power of 120 degrees C, resulting in endothelial denudation. The RFA method was approved in 1998 in Europe and in 1999 in the USA. The ClosurePLUS catheter was developed in 2003 and ClosureFAST in 2006. High occlusion rates and lower postoperative complication rates were reported with ClosureFAST than with ClosurePLUS. It is expected that this new ablation technique will control saphenous vein reflux with less pain and less ecchymosis after surgery. The treatment of varicose veins is less invasive with RFA devices and will become widely accepted as an alternative to conventional surgery for varicose veins in Japan. PMID:26281655

  3. Laser ablation loading of a radiofrequency ion trap

    NASA Astrophysics Data System (ADS)

    Zimmermann, K.; Okhapkin, M. V.; Herrera-Sancho, O. A.; Peik, E.

    2012-06-01

    The production of ions via laser ablation for the loading of radiofrequency (RF) ion traps is investigated using a nitrogen laser with a maximum pulse energy of 0.17 mJ and a peak intensity of about 250 MW/cm2. A time-of-flight mass spectrometer is used to measure the ion yield and the distribution of the charge states. Singly charged ions of elements that are presently considered for the use in optical clocks or quantum logic applications could be produced from metallic samples at a rate of the order of magnitude 105 ions per pulse. A linear Paul trap was loaded with Th+ ions produced by laser ablation. An overall ion production and trapping efficiency of 10-7 to 10-6 was attained. For ions injected individually, a dependence of the capture probability on the phase of the RF field has been predicted. In the experiment this was not observed, presumably because of collective effects within the ablation plume.

  4. Quality Improvement Guidelines for Radiofrequency Ablation of Liver Tumours

    SciTech Connect

    Crocetti, Laura; Baere, Thierry de; Lencioni, Riccardo

    2010-02-15

    The development of image-guided percutaneous techniques for local tumour ablation has been one of the major advances in the treatment of liver malignancies. Among these methods, radiofrequency ablation (RFA) is currently established as the primary ablative modality at most institutions. RFA is accepted as the best therapeutic choice for patients with early-stage hepatocellular carcinoma (HCC) when liver transplantation or surgical resection are not suitable options [1, 2]. In addition, RFA is considered a viable alternate to surgery (1) for inoperable patients with limited hepatic metastatic disease, especially from colorectal cancer, and (2) for patients deemed ineligible for surgical resection because of extent and location of the disease or concurrent medical conditions [3]. These guidelines were written to be used in quality-improvement programs to assess RFA of HCC and liver metastases. The most important processes of care are (1) patient selection, (2) performing the procedure, and (3) monitoring the patient. The outcome measures or indicators for these processes are indications, success rates, and complication rates.

  5. Surgical ablation for atrial fibrillation: The efficacy of a novel bipolar pen device in the cardioplegically arrested and beating heart

    PubMed Central

    Sakamoto, Shun-ichiro; Voeller, Rochus K.; Melby, Spencer J.; Lall, Shelly C.; Chang, Nai-lun; Schuessler, Richard B.; Damiano, Ralph J.

    2009-01-01

    Objective The introduction of ablation technology has simplified surgical intervention for atrial fibrillation. However, most ablation devices cannot create focal transmural lesions on the beating heart and have difficulty ablating specific regions of the atria, such as the atrioventricular isthmus, coronary sinus, and ganglionated plexus. The purpose of this study was to examine the efficacy of a pen-type bipolar radiofrequency ablation device on both arrested and beating hearts. Methods Endocardial and epicardial atrial tissues in the free wall, left atrial roof, atrioventricular annuli, and coronary sinus were ablated for varying time intervals (2.5–15 seconds) in porcine cardioplegically arrested (n = 6) and beating (n = 9) hearts. The hearts were stained with 1%2,3,5-triphenyl-tetrazolium chloride solution and sectioned to determine lesion depth and width. In 5 animals epicardial fat pads containing ganglionated plexus were stimulated and ablated. Results Lesion depth increased with ablation time similarly in both arrested and beating hearts. Transmurality was fully achieved in the thin atrial tissue (<4 mm) at 10 seconds in the beating and arrested hearts. The device had a maximal penetration depth of 6.1 mm. Epicardial ablation of the coronary sinus showed complete penetration through the left posterior atrium only in the arrested heart. Seven of 17 fat pads demonstrated a vagal response. All vagal responses were eliminated after ablation. Conclusion The bipolar pen effectively ablated atrial tissue in both arrested and beating hearts. This device might allow the surgeon to ablate tissue in regions not accessible to other devices during atrial fibrillation surgery. PMID:19026819

  6. Local Ablative Strategies for Ductal Pancreatic Cancer (Radiofrequency Ablation, Irreversible Electroporation): A Review.

    PubMed

    Paiella, Salvatore; Salvia, Roberto; Ramera, Marco; Girelli, Roberto; Frigerio, Isabella; Giardino, Alessandro; Allegrini, Valentina; Bassi, Claudio

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDAC) has still a dismal prognosis. Locally advanced pancreatic cancer (LAPC) accounts for the 40% of the new diagnoses. Current treatment options are based on chemo- and radiotherapy regimens. Local ablative techniques seem to be the future therapeutic option for stage-III patients with PDAC. Radiofrequency Ablation (RFA) and Irreversible Electroporation (IRE) are actually the most emerging local ablative techniques used on LAPC. Initial clinical studies on the use of these techniques have already demonstrated encouraging results in terms of safety and feasibility. Unfortunately, few studies on their efficacy are currently available. Even though some reports on the overall survival are encouraging, randomized studies are still required to corroborate these findings. This study provides an up-to-date overview and a thematic summary of the current available evidence on the application of RFA and IRE on PDAC, together with a comparison of the two procedures. PMID:26981115

  7. Local Ablative Strategies for Ductal Pancreatic Cancer (Radiofrequency Ablation, Irreversible Electroporation): A Review

    PubMed Central

    Paiella, Salvatore; Salvia, Roberto; Ramera, Marco; Girelli, Roberto; Frigerio, Isabella; Giardino, Alessandro; Allegrini, Valentina; Bassi, Claudio

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDAC) has still a dismal prognosis. Locally advanced pancreatic cancer (LAPC) accounts for the 40% of the new diagnoses. Current treatment options are based on chemo- and radiotherapy regimens. Local ablative techniques seem to be the future therapeutic option for stage-III patients with PDAC. Radiofrequency Ablation (RFA) and Irreversible Electroporation (IRE) are actually the most emerging local ablative techniques used on LAPC. Initial clinical studies on the use of these techniques have already demonstrated encouraging results in terms of safety and feasibility. Unfortunately, few studies on their efficacy are currently available. Even though some reports on the overall survival are encouraging, randomized studies are still required to corroborate these findings. This study provides an up-to-date overview and a thematic summary of the current available evidence on the application of RFA and IRE on PDAC, together with a comparison of the two procedures. PMID:26981115

  8. A Retrospective Comparison of Microwave Ablation vs. Radiofrequency Ablation for Colorectal Cancer Hepatic Metastases

    PubMed Central

    Correa-Gallego, Camilo; Fong, Yuman; Gonen, Mithat; D'Angelica, Michael I.; Allen, Peter J.; DeMatteo, Ronald P.; Jarnagin, William R.; Kingham, T. Peter

    2015-01-01

    Background Microwave (MWA) and radiofrequency ablation (RFA) are the most commonly used techniques for ablating colorectal-liver metastases (CRLM). The technical and oncologic differences between these modalities are unclear. Methods We conducted a matched-cohort analysis of patients undergoing open MWA or RFA for CRLM at a tertiary-care center between 2008 and 2011; the primary endpoint was ablation-site recurrence. Tumors were matched by size, clinical-risk score, and arterial-intrahepatic or systemic chemotherapy use. Outcomes were compared using conditional logistic regression and stratified log-rank test. Results We matched 254 tumors (127 per group) from 134 patients. MWA and RFA groups were comparable by age, gender, median number of tumors treated, proximity to major vessels, and postoperative complication rates. Patients in the MWA group had lower ablation-site recurrence rates (6% vs. 20%; P < 0.01). Median follow-up, however, was significantly shorter in the MWA group (18 months [95% confidence interval 17–20] vs. 31 months [95% confidence interval 28–35]; P < 0.001). Kaplan–Meier estimates of ablation-site recurrence at 2 years were significantly lower for the lesions treated with MWA (7% vs. 18%, P: 0.01). Conclusions Ablation-site recurrences of CRLM were lower with MWA compared with RFA in this matched cohort analysis. Longer follow-up time in the MWA may increase the recurrence rate; however, actuarial local failure estimations demonstrated better local control with MWA. PMID:24889486

  9. GPU-based real-time approximation of the ablation zone for radiofrequency ablation.

    PubMed

    Rieder, Christian; Kröger, Tim; Schumann, Christian; Hahn, Horst K

    2011-12-01

    Percutaneous radiofrequency ablation (RFA) is becoming a standard minimally invasive clinical procedure for the treatment of liver tumors. However, planning the applicator placement such that the malignant tissue is completely destroyed, is a demanding task that requires considerable experience. In this work, we present a fast GPU-based real-time approximation of the ablation zone incorporating the cooling effect of liver vessels. Weighted distance fields of varying RF applicator types are derived from complex numerical simulations to allow a fast estimation of the ablation zone. Furthermore, the heat-sink effect of the cooling blood flow close to the applicator's electrode is estimated by means of a preprocessed thermal equilibrium representation of the liver parenchyma and blood vessels. Utilizing the graphics card, the weighted distance field incorporating the cooling blood flow is calculated using a modular shader framework, which facilitates the real-time visualization of the ablation zone in projected slice views and in volume rendering. The proposed methods are integrated in our software assistant prototype for planning RFA therapy. The software allows the physician to interactively place virtual RF applicator models. The real-time visualization of the corresponding approximated ablation zone facilitates interactive evaluation of the tumor coverage in order to optimize the applicator's placement such that all cancer cells are destroyed by the ablation. PMID:22034298

  10. Consensus for the Treatment of Varicose Vein with Radiofrequency Ablation

    PubMed Central

    Joh, Jin Hyun; Kim, Woo-Shik; Jung, In Mok; Park, Ki-Hyuk; Lee, Taeseung; Kang, Jin Mo

    2014-01-01

    The objective of this paper is to introduce the schematic protocol of radiofrequency (RF) ablation for the treatment of varicose veins. Indication: anatomic or pathophysiologic indication includes venous diameter within 2–20 mm, reflux time ≥0.5 seconds and distance from the skin ≥5 mm or subfascial location. Access: it is recommended to access at or above the knee joint for great saphenous vein and above the mid-calf for small saphenous vein. Catheter placement: the catheter tip should be placed 2.0 cm inferior to the saphenofemoral or saphenopopliteal junction. Endovenous heat-induced thrombosis ≥class III should be treated with low-molecular weight heparin. Tumescent solution: the composition of solution can be variable (e.g., 2% lidocaine 20 mL+500 mL normal saline+bicarbonate 2.5 mL with/without epinephrine). Infiltration can be done from each direction. Ablation: two cycles’ ablation for the first proximal segment of saphenous vein and the segment with the incompetent perforators is recommended. The other segments should be ablated one time. During RF energy delivery, it is recommended to apply external compression. Concomitant procedure: It is recommended to do simultaneously ambulatory phlebectomy. For sclerotherapy, it is recommended to defer at least 2 weeks. Post-procedural management: post-procedural ambulation is encouraged to reduce the thrombotic complications. Compression stocking should be applied for at least 7 days. Minor daily activity is not limited, but strenuous activities should be avoided for 2 weeks. It is suggested to take showers after 24 hours and tub baths, swimming, or soaking in water after 2 weeks. PMID:26217628

  11. Percutaneous Radiofrequency Ablation for Treatment of Recurrent Retroperitoneal Liposarcoma

    SciTech Connect

    Keil, Sebastian Bruners, Philipp; Brehmer, Bernhard; Mahnken, Andreas Horst

    2008-07-15

    Percutaneous CT-guided radiofrequency ablation (RFA) is becoming more and more established in the treatment of various neoplasms, including retroperitoneal tumors of the kidneys and the adrenal glands. We report the case of RFA in a patient suffering from the third relapse of a retroperitoneal liposarcoma in the left psoas muscle. After repeated surgical resection and supportive radiation therapy of a primary retroperitoneal liposarcoma and two surgically treated recurrences, including replacement of the ureter by a fraction of the ileum, there was no option for further surgery. Thus, we considered RFA as the most suitable treatment option. Monopolar RFA was performed in a single session with a 2-cm umbrella-shaped LeVeen probe. During a 27-month follow-up period the patient remained free of tumor.

  12. Radiofrequency ablation of a misdiagnosed Brodie’s abscess

    PubMed Central

    Chan, RS; Abdullah, BJJ; Aik, S; Tok, CH

    2011-01-01

    Radiofrequency ablation (RFA) therapy is recognised as a safe and effective treatment option for osteoid osteoma. This case report describes a 27-year-old man who underwent computed tomography (CT)-guided percutaneous RFA for a femoral osteoid osteoma, which was diagnosed based on his clinical presentation and CT findings. The patient developed worsening symptoms complicated by osteomyelitis after the procedure. His clinical progression and subsequent MRI findings had led to a revised diagnosis of a Brodie’s abscess, which was further supported by the eventual resolution of his symptoms following a combination of antibiotics treatment and surgical irrigations. This case report illustrates the unusual MRI features of osteomyelitis mimicking soft tissue tumours following RFA of a misdiagnosed Brodie’s abscess and highlights the importance of a confirmatory histopathological diagnosis for an osteoid osteoma prior to treatment. PMID:22291860

  13. [Ablation using radiofrequency in the treatment of ventricular tachycardia].

    PubMed

    Cordero Cabra, J A; Iturralde Torres, P; Lara Vaca, S; Colín Lizalde, L; Kershenovich, S; Carvajal, A; González Hermosillo, J A

    1996-01-01

    We performed radiofrequency catheter ablation in 14 consecutive patients with Ventricular Tachycardia (VT) 10 of which had healthy hearts, one patient with ischemic heart disease, one with arrhythmogenic dysplasia, one with dilated cardiomyopathy, and one with congenital heart disease. The localization of the VT was: 10 in the left posterior fascicular region, 3 in the right ventricular outflow tract (RVOT), and one patient with ischemic heart disease with the substrate in the left ventricular apex. All of them with VT refractory to pharmacological management, using an average of 2.7 drugs per patient. After all patients underwent Electrophysiological Study (EPS), an intracavitary mapping was performed, in order to locate the arrhythmogenic substrate. Later on, the RF ablation was performed, delivering an average of 15 pulses, using 40 Watts, and an average time of 25 sec. per pulse. The procedure was successful in 60% of the fascicular VT, with a 16% of recurrence; 100% of success with those originated in the RVOT with no recurrence; in the ischemic patient we achieved primary success, but with recurrence, a second session was successful with no recurrence up to date. No major complications occurred in this group. Those patients which showed no success required the use of antiarrhythmic drugs. The total success of the series is 71.4% with 10% recurrence, and no mortality. PMID:8967816

  14. Radiofrequency ablation in an infant with recurrent supraventricular tachycardia and cyanosis

    PubMed Central

    Vora, Amit; Lokhandwala, Yash; Sheth, Chirag; Dalvi, Bharat

    2009-01-01

    We report an unusual presentation of supraventricular tachycardia, in an infant, with cyanosis. The child had atrial septal defect with hypoplastic right ventricle. Radiofrequency ablation was performed in view of drug resistant SVT PMID:20808630

  15. Getting your signals straight. Comparing radio-frequency ablation and cryoablation for treating cardiac arrhythmias.

    PubMed

    2010-08-01

    Radio-frequency ablation has proven to be an effective method for treating cardiac arrhythmias. However, a newer treatment method called cryoablation is becoming increasingly popular. In this article, we discuss the advantages and disadvantages of each. PMID:21305902

  16. Radiofrequency ablation for postsurgical thyroid removal of differentiated thyroid carcinoma

    PubMed Central

    Xu, Dong; Wang, Lipin; Long, Bin; Ye, Xuemei; Ge, Minghua; Wang, Kejing; Guo, Liang; Li, Linfa

    2016-01-01

    Differentiated thyroid carcinoma (DTC) is the most common endocrine malignancy. Surgical removal with radioactive iodine therapy is recommended for recurrent thyroid carcinoma, and the postsurgical thyroid removal is critical. This study evaluated the clinical values of radiofrequency ablation (RFA) in the postsurgical thyroid removal for DTC. 35 DTC patients who had been treated by subtotal thyroidectomy received RFA for postsurgical thyroid removal. Before and two weeks after RFA, the thyroid was examined by ultrasonography and 99mTcO4 - thyroid imaging, and the serum levels of free triiodothyronine (FT3), free thyroxin (FT4), thyroid stimulating hormone (TSH) and thyroglobulin (Tg) were detected. The efficacy and complications of RFA were evaluated. Results showed that, the postsurgical thyroid removal by RFA was successfully performed in 35 patients, with no significant complication. After RFA, the average largest diameter and volume were significantly decreased in 35 patients (P > 0.05), and no obvious contrast media was observed in ablation area in the majority of patients. After RFA, the serum FT3, FT4 and Tg levels were markedly decreased (P < 0.05), and TSH level was significantly increased (P < 0.05). After RFA, radioiodine concentration in the ablation area was significantly reduced in the majority of patients. The reduction rate of thyroid update was 0.69±0.20%. DTC staging and interval between surgery and RFA had negative correlation (Pearson coefficient = -0.543; P = 0.001), with no obvious correlation among others influential factors. RFA is an effective and safe method for postsurgical thyroid removal of DTC. PMID:27186311

  17. Radiofrequency ablation for postsurgical thyroid removal of differentiated thyroid carcinoma.

    PubMed

    Xu, Dong; Wang, Lipin; Long, Bin; Ye, Xuemei; Ge, Minghua; Wang, Kejing; Guo, Liang; Li, Linfa

    2016-01-01

    Differentiated thyroid carcinoma (DTC) is the most common endocrine malignancy. Surgical removal with radioactive iodine therapy is recommended for recurrent thyroid carcinoma, and the postsurgical thyroid removal is critical. This study evaluated the clinical values of radiofrequency ablation (RFA) in the postsurgical thyroid removal for DTC. 35 DTC patients who had been treated by subtotal thyroidectomy received RFA for postsurgical thyroid removal. Before and two weeks after RFA, the thyroid was examined by ultrasonography and (99m)TcO4 (-) thyroid imaging, and the serum levels of free triiodothyronine (FT3), free thyroxin (FT4), thyroid stimulating hormone (TSH) and thyroglobulin (Tg) were detected. The efficacy and complications of RFA were evaluated. Results showed that, the postsurgical thyroid removal by RFA was successfully performed in 35 patients, with no significant complication. After RFA, the average largest diameter and volume were significantly decreased in 35 patients (P > 0.05), and no obvious contrast media was observed in ablation area in the majority of patients. After RFA, the serum FT3, FT4 and Tg levels were markedly decreased (P < 0.05), and TSH level was significantly increased (P < 0.05). After RFA, radioiodine concentration in the ablation area was significantly reduced in the majority of patients. The reduction rate of thyroid update was 0.69±0.20%. DTC staging and interval between surgery and RFA had negative correlation (Pearson coefficient = -0.543; P = 0.001), with no obvious correlation among others influential factors. RFA is an effective and safe method for postsurgical thyroid removal of DTC. PMID:27186311

  18. Palliative Treatment of Rectal Carcinoma Recurrence Using Radiofrequency Ablation

    SciTech Connect

    Mylona, Sophia Karagiannis, Georgios Patsoura, Sofia; Galani, Panagiota; Pomoni, Maria; Thanos, Loukas

    2012-08-15

    Purpose: To evaluate the safety and efficacy of CT-guided radiofrequency (RF) ablation for the palliative treatment of recurrent unresectable rectal tumors. Materials and Methods: Twenty-seven patients with locally recurrent rectal cancer were treated with computed tomography (CT)-guided RF ablation. Therapy was performed with the patient under conscious sedation with a seven- or a nine-array expandable RF electrode for 8-10 min at 80-110 Degree-Sign C and a power of 90-110 W. All patients went home under instructions the next day of the procedure. Brief Pain Inventory score was calculated before and after (1 day, 1 week, 1 month, 3 months, and 6 months) treatment. Results: Complete tumor necrosis rate was 77.8% (21 of a total 27 procedures) despite lesion location. BPI score was dramatically decreased after the procedure. The mean preprocedure BPI score was 6.59, which decreased to 3.15, 1.15, and 0.11 at postprocedure day 1, week 1, and month 1, respectively, after the procedure. This decrease was significant (p < 0.01 for the first day and p < 0.001 for the rest of the follow-up intervals (paired Student t test; n - 1 = 26) for all periods during follow-up. Six patients had partial tumor necrosis, and we were attempted to them with a second procedure. Although the necrosis area showed a radiographic increase, no complete necrosis was achieved (secondary success rate 65.6%). No immediate or delayed complications were observed. Conclusion: CT-guided RF ablation is a minimally invasive, safe, and highly effective technique for treatment of malignant rectal recurrence. The method is well tolerated by patients, and pain relief is quickly achieved.

  19. Papillary Thyroid Carcinoma Treated with Radiofrequency Ablation in a Patient with Hypertrophic Cardiomyopathy: A Case Report

    PubMed Central

    Sun, Jianyi; Liu, Xiaosun; Zhang, Qing; Hong, Yanyun; Song, Bin; Teng, Xiaodong

    2016-01-01

    Standard therapy has not been established for thyroid cancer when a thyroidectomy is contraindicated due to systemic disease. Herein, we reported a patient who had hypertrophic cardiomyopathy and papillary thyroid carcinoma treated by radiofrequency ablation because of inability to tolerate a thyroidectomy. Radiofrequency ablation can be used to treat thyroid cancer when surgery is not feasible, although the long-term outcome needs further observation. PMID:27390548

  20. Radiofrequency Ablation of Benign Thyroid Nodules and Recurrent Thyroid Cancers: Consensus Statement and Recommendations

    PubMed Central

    Na, Dong Gyu; Lee, Jeong Hyun; Jung, So Lyung; Kim, Ji-hoon; Sung, Jin Yong; Shin, Jung Hee; Kim, Eun-Kyung; Lee, Joon Hyung; Kim, Dong Wook; Park, Jeong Seon; Kim, Kyu Sun; Baek, Seon Mi; Lee, Younghen; Chong, Semin; Sim, Jung Suk; Huh, Jung Yin; Bae, Jae-Ik; Kim, Kyung Tae; Han, Song Yee; Bae, Min Young; Kim, Yoon Suk

    2012-01-01

    Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus. PMID:22438678

  1. Papillary Thyroid Carcinoma Treated with Radiofrequency Ablation in a Patient with Hypertrophic Cardiomyopathy: A Case Report.

    PubMed

    Sun, Jianyi; Liu, Xiaosun; Zhang, Qing; Hong, Yanyun; Song, Bin; Teng, Xiaodong; Yu, Jiren

    2016-01-01

    Standard therapy has not been established for thyroid cancer when a thyroidectomy is contraindicated due to systemic disease. Herein, we reported a patient who had hypertrophic cardiomyopathy and papillary thyroid carcinoma treated by radiofrequency ablation because of inability to tolerate a thyroidectomy. Radiofrequency ablation can be used to treat thyroid cancer when surgery is not feasible, although the long-term outcome needs further observation. PMID:27390548

  2. Radiofrequency catheter ablation of accessory atrioventricular pathways in children and young adults.

    PubMed Central

    Sreeram, N; Smeets, J L; Pulles-Heintzberger, C F; Wellens, H J

    1993-01-01

    OBJECTIVE--To assess the efficacy of radiofrequency ablation for reentrant tachyarrhythmias in children and young adults. SETTING--A tertiary cardiac referral centre. PATIENTS AND INTERVENTIONS--Over a 16 month period 22 patients aged less than 20 years (median age 16.5 years) underwent 26 radiofrequency ablation procedures for atrioventricular reentry tachycardia through an accessory pathway. The results of radiofrequency ablation were compared with those in a group of 16 patients (median age 14 years) who had had surgical ablation for atrioventricular reentry tachycardia over a preceding six year period. RESULTS--Ablation of an accessory atrioventricular pathway was accomplished for 18 (76%) of 25 pathways in 16 (73%) of 22 patients. There were no procedure-related complications. Surgery was eventually curative in 15/16 patients (94%). However, three patients required a second open heart surgical procedure because tachyarrhythmia recurred. There were no surgical deaths. Failures for radiofrequency ablation were related to accessory pathway location, and were greater for right free wall and posteroseptal pathways (success rate of 50% and 57% respectively). Recurrence after surgery was also associated with pathways in these locations. CONCLUSIONS--Transcatheter radiofrequency current ablation was safe and achieved a cure with less patient morbidity and improved cost efficiency. It is an attractive alternative to long-term drug therapy or surgery in older children and adolescents. A higher success rate may be expected with increased experience. PMID:8038027

  3. Treatment of Uterine Myomas by Radiofrequency Thermal Ablation

    PubMed Central

    Chen, Ming; Yang, Shujun; Li, Juan; Zhu, Tongyu; Zhao, Xiaoli

    2015-01-01

    Patients’ selection criteria, effectiveness, and safety of radiofrequency thermal ablation (RFTA) therapy for uterine myomas (UM) were assessed using a 10-year retrospective cohort study. From July 2001 to July 2011, a total of 1216 patients treated for UM were divided into 2 groups. Group A consisted of 476 premenopause patients, average age 36.5 ± 8.5 years, average number of myomas 1.7 ± 0.9, and average diameter of myomas 4.5 ± 1.5 cm, and group B consisted of 740 menopause patients, average age 48.5 ± 3.5 years, average number of myomas 2.6 ± 1.3, and average diameter of myomas 5.0 ± 2.5 cm. Average follow-up period was 36.5 ± 11.5 months. At 1, 3, 6, 12, and 24 months after RFTA, average diameters of myomas in group A were 3.8, 3.0, 2.7, 2.4, and 2.2 cm, respectively, and 47.7% (227 of 476) of patients had tumor trace at 12 months after RFTA. In group B, the results were 4.7, 3.7, 3.3, 2.3, and 2.3 cm, respectively, and 58.8% (435 of 740) of patients had tumor trace at 12 months after RFTA. Three months after treatment, myoma volumes were significantly reduced in both the groups (P < .01), and group B had higher rate of tumor trace at 12 months after RFTA than group A (P < .05). Clinical symptoms and health-related quality-of-life outcome (HRQL) were significantly improved after RFTA in both groups and the postoperative recurrence rate of UM was significantly higher in group A at 10.7% (51 of 476) than group B at 2.4% (18 of 740; P < .05). Radiofrequency thermal ablation is an excellent minimally invasive treatment for UM smaller than 5.0 cm in diameter. PMID:25355802

  4. Effectiveness of impedance monitoring during radiofrequency ablation for predicting popping

    PubMed Central

    Iida, Hiroya; Aihara, Tsukasa; Ikuta, Shinichi; Yamanaka, Naoki

    2012-01-01

    AIM: To retrospectively evaluate the effectiveness of impedance monitoring for predicting popping during radiofrequency ablation (RFA) using internally cooled electrodes. METHODS: We reviewed 140 patients (94 males, 46 females; age range 73.0 ± 11.1 year) who underwent RFA between February 2006 and November 2008 with a modified protocol using a limited power delivery rather than a conventional one to avoid popping. All the patients provided their written informed consent, and the study was approved by the institutional review board. Intraprocedural impedances were measured for the study subjects, and the tumors were classified into three types according to the characteristics of their impedance curves: increasing, flat, or decreasing. The tumors were further sorted into seven subtypes (A-G) depending on the curvature of the impedance curve’s increase or decrease. Relative popping rates were determined for the three types and seven subtypes. A chi-square test was performed to estimate statistical significance. RESULTS: A total of 148 nodules treated by RFA were analyzed. The study samples included 132 nodules of hepatocellular carcinoma, 14 nodules of metastatic liver cancer, and two nodules of intrahepatic cholangiocarcinoma. The numbers of nodules with each impedance curve type were as follows: 37 increasing-type nodules, 43 flat-type nodules, and 68 decreasing-type nodules. Popping occurrence rates were 24.3%, 46.5% and 64.7%, respectively. Flat-type nodules exhibited a significantly higher rate of popping compared to increasing-type nodules (P = 0.039). Decreasing-type nodules exhibited a significantly higher rate of popping compared to increasing-type nodules (P < 0.0001). Notably, nodules that showed a sharp decrease in impedance in the latter ablation period (subtype E) exhibited a significantly higher rate of popping compared to other subtypes. CONCLUSION: Intraprocedural impedance monitoring can be a useful tool to predict the occurrence of popping

  5. Radiofrequency Ablation for Postoperative Recurrences of Intrahepatic Cholangiocarcinoma

    PubMed Central

    Fu, Ying; Yang, Wei; Wu, Wei; Yan, Kun; Xing, Bao-cai

    2011-01-01

    Objective Most recurrent intrahepatic cholangiocarcinoma (RICC) lost the opportunity of radical resection while most nonsurgical management failed to prolong patients’ survival. The efficacy and safety of radiofrequency ablation (RFA) as a local treatment for recurrent hepatocellular carcinoma have been confirmed by many clinical studies. The purpose of this study was to evaluate the efficacy, long-term survival and complications of RFA for RICC. Methods A total of 12 patients with 19 RICCs after radical resection were included in this study. The tumors were 1.9-6.8 cm at the maximum diameter (median, 3.2±1.6 cm). All patients were treated with ultrasound guided RFA. There were two RFA approaches including percutaneous and open. Results A total of 18 RFA treatment sessions were performed. Ablation was successful (evaluated by 1-month CT after the initial RFA procedure) in 18 (94.7%) of 19 tumors. By a median follow-up period of 29.9 months after RFA, 5 patients received repeated RFA because of intrahepatic lesion recurrence. The median local recurrence-free survival period and median event-free survival period after RFA were 21.0 months and 13.0 months, respectively. The median overall survival was 30 months, and the 1- and 3-year survival rates were 87.5% and 37.5%, respectively. The complication rate was 5.6% (1/18 sessions). The only one major complication was pleural effusion requiring thoracentesis. Conclusion This study showed RFA may effectively and safely manage RICC with 3-year survival of 37.5%. It provides a treatment option for these RICC patients who lost chance for surgery. PMID:23359754

  6. Outcome after Radiofrequency Ablation of Sarcoma Lung Metastases

    SciTech Connect

    Koelblinger, Claus; Strauss, Sandra; Gillams, Alice

    2013-05-14

    PurposeResection is the mainstay of management in patients with sarcoma lung metastases, but there is a limit to how many resections can be performed. Some patients with inoperable disease have small-volume lung metastases that are amenable to thermal ablation. We report our results after radiofrequency ablation (RFA).MethodsThis is a retrospective study of patients treated from 2007 to 2012 in whom the intention was to treat all sites of disease and who had a minimum CT follow-up of 4 months. Treatment was performed under general anesthesia/conscious sedation using cool-tip RFA. Follow-up CT scans were analyzed for local control. Primary tumor type, location, grade, disease-free interval, prior resection/chemotherapy, number and size of lung tumors, uni- or bilateral disease, complications, and overall and progression-free survival were recorded.ResultsTwenty-two patients [15 women; median age 48 (range 10–78) years] with 55 lung metastases were treated in 30 sessions. Mean and median tumor size and initial number were 0.9 cm and 0.7 (range 0.5–2) cm, and 2.5 and 1 (1–7) respectively. Median CT and clinical follow-up were 12 (4–54) and 20 (8–63) months, respectively. Primary local control rate was 52 of 55 (95 %). There were 2 of 30 (6.6 %) Common Terminology Criteria grade 3 complications with no long-term sequelae. Mean (median not reached) and 2- and 3-year overall survival were 51 months, and 94 and 85 %. Median and 1- and 2-year progression-free survival were 12 months, and 53 and 23 %. Prior disease-free interval was the only significant factor to affect overall survival.ConclusionRFA is a safe and effective treatment for patients with small-volume sarcoma metastases.

  7. Optoacoustic monitoring of real-time lesion formation during radiofrequency catheter ablation

    NASA Astrophysics Data System (ADS)

    Pang, Genny A.; Bay, Erwin; Deán-Ben, Xosé L.; Razansky, Daniel

    2015-03-01

    Current radiofrequency cardiac ablation procedures lack real-time lesion monitoring guidance, limiting the reliability and efficacy of the treatment. The objective of this work is to demonstrate that optoacoustic imaging can be applied to develop a diagnostic technique applicable to radiofrequency ablation for cardiac arrhythmia treatment with the capabilities of real-time monitoring of ablated lesion size and geometry. We demonstrate an optoacoustic imaging method using a 256-detector optoacoustic imaging probe and pulsed-laser illumination in the infrared wavelength range that is applied during radiofrequency ablation in excised porcine myocardial tissue samples. This technique results in images with high contrast between the lesion volume and unablated tissue, and is also capable of capturing time-resolved image sequences that provide information on the lesion development process. The size and geometry of the imaged lesion were shown to be in excellent agreement with the histological examinations. This study demonstrates the first deep-lesion real-time monitoring for radiofrequency ablation generated lesions, and the technique presented here has the potential for providing critical feedback that can significantly impact the outcome of clinical radiofrequency ablation procedures.

  8. Thermistor guided radiofrequency ablation of atrial insertion sites in patients with accessory pathways.

    PubMed

    Tracy, C M; Moore, H J; Solomon, A J; Rodak, D J; Fletcher, R D

    1995-11-01

    Radiofrequency ablation has gained acceptance in the treatment of patients with symptomatic Wolff-Parkinson-White syndrome. The purpose of this study was to characterize the relation between temperature and other electroconductive parameters in patients undergoing atrial insertion accessory pathway ablation utilizing a thermistor equipped catheter. The mean temperature and power at sites of atrial insertion ablation are lower than has been previously associated with creation of radiofrequency lesions in the ventricle. While high cavitary blood flow in the atrium may result in cooling, the thinner atrial tissue may require less energy to achieve adequate heating than ventricular myocardium. PMID:8552513

  9. A review of the general aspects of radiofrequency ablation.

    PubMed

    Ni, Y; Mulier, S; Miao, Y; Michel, L; Marchal, G

    2005-01-01

    As an alternative to standard surgical resection for the treatment of malignant tumors, radiofrequency ablation (RFA) has rapidly evolved into the most popular minimally invasive therapy. To help readers gain the relevant background knowledge and to better understand the other reviews in this Feature Section on the clinical applications of RFA in different abdominal organs, the present report covers the general aspects of RFA. After an introduction, we present a simple definition of the energy applied during RFA, a brief historical review of its technical evolution, and an explanation of the mechanism of action of RFA. These basic discussions are substantiated with descriptions of RFA equipment including those commercially available and those under preclinical development. The size and geometry of induced lesions in relation to RFA efficacy and side effects are discussed. The unique pathophysiologic process of thermal tissue damage and the corresponding histomorphologic manifestations after RFA are detailed and cross-referenced with the findings in the current literature. The crucial role of imaging technology during and after RFA is also addressed, including some promising new developments. This report finishes with a summary of the key messages and a perspective on further technologic refinements and identifies some specific priorities. PMID:15776302

  10. Supercomputer Simulation of Radio-frequency Hepatic Tumor Ablation

    NASA Astrophysics Data System (ADS)

    Kosturski, N.; Margenov, S.

    2010-11-01

    We simulate the thermal and electrical processes, involved in the radio-frequency (RF) ablation procedure. The mathematical model consists of two parts—electrical and thermal. The energy from the applied AC voltage is determined first, by solving the Laplace equation to find the potential distribution. After that, the electric field intensity and the current density are directly calculated. Finally, the heat transfer equation is solved to determine the temperature distribution. Heat loss due to blood perfusion is also accounted for. The representation of the computational domain is based on a voxel mesh. Both partial differential equations are discretized in space via linear conforming FEM. After the space discretization, the backward Euler scheme is used for the time stepping. Large-scale linear systems arise from the FEM discretization. Moreover, they are ill-conditioned, due to the strong coefficient jumps and the complex geometry of the problem. Therefore, efficient parallel solution methods are required. The developed parallel solver is based on the preconditioned conjugate gradient (PCG) method. As a preconditioner, we use BoomerAMG—a parallel algebraic multigrid implementation from the package Hypre, developed in LLNL, Livermore. Parallel numerical tests, performed on the IBM Blue Gene/P massively parallel computer are presented.

  11. Surgical and Pathological Changes after Radiofrequency Ablation of Thyroid Nodules

    PubMed Central

    Dobrinja, Chiara; Bernardi, Stella; Fabris, Bruno; Eramo, Rita; Makovac, Petra; Bazzocchi, Gabriele; Piscopello, Lanfranco; Barro, Enrica; de Manzini, Nicolò; Bonazza, Deborah; Pinamonti, Maurizio; Zanconati, Fabrizio; Stacul, Fulvio

    2015-01-01

    Background. Radiofrequency ablation (RFA) has been recently advocated as an effective technique for the treatment of symptomatic benign thyroid nodules. It is not known to what extent it may affect any subsequent thyroid surgery and/or histological diagnosis. Materials and Methods. RFA was performed on 64 symptomatic Thy2 nodules (benign nodules) and 6 symptomatic Thy3 nodules (follicular lesions/follicular neoplasms). Two Thy3 nodules regrew after the procedure, and these patients accepted to undergo a total thyroidectomy. Here we present how RFA has affected the operation and the final pathological features of the surgically removed nodules. Results and Conclusions. RFA is effective for the treatment of Thy2 nodules, but it should not be recommended as first-line therapy for the treatment of Thy3 nodules (irrespective of their mutational status), as it delays surgery in case of malignancy. Moreover, it is unknown whether RFA might promote residual tumor progression or neoplastic progression of Thy3 lesions. Nevertheless, here we show for the first time that one session of RFA does not affect subsequent thyroid surgery and/or histological diagnosis. PMID:26265914

  12. Hepatic Cryoablation, But Not Radiofrequency Ablation, Results in Lung Inflammation

    PubMed Central

    Chapman, William C.; Debelak, Jacob P.; Wright Pinson, C.; Washington, M. Kay; Atkinson, James B.; Venkatakrishnan, Annapurna; Blackwell, Timothy S.; Christman, John W.

    2000-01-01

    Objective To compare the effects of 35% hepatic cryoablation with a similar degree of radiofrequency ablation (RFA) on lung inflammation, nuclear factor κB (NF-κB) activation, and production of NF-κB dependent cytokines. Summary Background Data Multisystem injury, including acute lung injury, is a severe complication associated with hepatic cryoablation of 30% to 35% or more of liver parenchyma, but this complication has not been reported with RFA. Methods Sprague-Dawley rats underwent 35% hepatic cryoablation or RFA and were killed at 1, 2, and 6 hours. Liver and lung tissue were freeze-clamped for measurement of NF-κB activation, which was detected by electrophoretic mobility shift assay. Serum concentrations of tumor necrosis factor α and macrophage inflammatory protein 2 were measured by enzyme-linked immunosorbent assay. Histologic studies of pulmonary tissue and electron microscopy of ablated liver tissue were compared among treatment groups. Results Histologic lung sections after cryoablation showed multiple foci of perivenular inflammation, with activated lymphocytes, foamy macrophages, and neutrophils. In animals undergoing RFA, inflammatory foci were not present. NF-κB activation was detected at 1 hour in both liver and lung tissue samples of animals undergoing cryoablation but not after RFA, and serum cytokine levels were significantly elevated in cryoablation versus RFA animals. Electron microscopy of cryoablation-treated liver tissue demonstrated disruption of the hepatocyte plasma membrane with extension of intact hepatocyte organelles into the space of Disse; RFA-treated liver tissue demonstrated coagulative destruction of hepatocyte organelles within an intact plasma membrane. To determine the stimulus for systemic inflammation, rats treated with cryoablation had either immediate resection of the ablated segment or delayed resection after a 15-minute thawing interval. Immediate resection of the cryoablated liver tissue prevented NF

  13. Variation of tumoral marker after radiofrequency ablation of pancreatic adenocarcinoma

    PubMed Central

    Barbi, Emilio; Girelli, Roberto; Tinazzi Martini, Paolo; De Robertis, Riccardo; Ciaravino, Valentina; Salvia, Roberto; Butturini, Giovanni; Frigerio, Isabella; Milazzo, Teresa; Crosara, Stefano; Paiella, Salvatore; Pederzoli, Paolo; Bassi, Claudio

    2016-01-01

    Background To evaluate the correlation between variations of CA 19.9 blood levels and the entity of necrosis at CT after radiofrequency ablation (RFA) of unresectable pancreatic adenocarcinoma. Methods In this study, from June 2010 to February 2014, patients with diagnosis of unresectable and not metastatic pancreatic ductal adenocarcinoma, expressing tumor marker CA 19.9, treated with RFA procedure were included. All these patients underwent RFA. CT study was performed 1 week after RFA. The dosage of CA 19.9 levels was performed 1 month after RFA. Features of necrosis at CT, as mean entity, density and necrosis percentages compared to the original lesion, were evaluated and compared by using t-test with CA 19.9 blood levels variations after RFA procedure. Results In this study were included 51 patients with diagnosis of unresectable and not metastatic pancreatic ductal adenocarcinoma, expressing tumor marker CA 19.9, treated with RFA procedure and with CT study and CA 19.9 available for analysis. After the procedure, CA 19.9 blood levels reduced in 24/51 (47%), remained stable in 10/51 (20%) and increased in 17/51 (33%). In patients with CA 19.9 levels reduced, the tumor marker were reduced less than 20% in 4/24 (17%) and more than 20% in 20/24 (83%); instead the tumor marker were reduced less than 30% in 8/24 (33%) and more than 30% in 16/24 (67%). At CT scan necrotic area density difference was not statistically significant. Also there was no statistically significant difference among the mean area, the mean volume and the mean ablation volume in percentage related to the treated tumor among the three different groups of patients divided depending on the CA 19.9 blood levels. But a tendency to a statistically significant difference was found in comparing the mean percentage of ablation volume between two subgroups of patients with a decrease of CA 19.9 levels with less or more than 20% reduction of tumor markers and between two subgroups with less or more than

  14. Radiofrequency Ablation of Subpleural Lung Malignancy: Reduced Pain Using an Artificially Created Pneumothorax

    SciTech Connect

    Lee, Edward W. Suh, Robert D.; Zeidler, Michelle R.; Tsai, Irene S.; Cameron, Robert B.; Abtin, Fereidoun G.; Goldin, Jonathan G.

    2009-07-15

    One of the main issues with radiofrequency (RF) ablation of the subpleural lung malignancy is pain management during and after RF ablation. In this article, we present a case that utilized a technique to decrease the pain associated with RF ablation of a malignancy located within the subpleural lung. Under CT guidance, we created an artificial pneumothorax prior to the RF ablation, which resulted in minimizing the pain usually experienced during and after the procedure. It also decreased the amount of pain medications usually used in patients undergoing RF ablation of a subpleural lung lesion.

  15. Percutaneous microwave ablation vs radiofrequency ablation in the treatment of hepatocellular carcinoma.

    PubMed

    Poulou, Loukia S; Botsa, Evanthia; Thanou, Ioanna; Ziakas, Panayiotis D; Thanos, Loukas

    2015-05-18

    Hepatocellular cancer ranks fifth among cancers and is related to chronic viral hepatitis, alcohol abuse, steatohepatitis and liver autoimmunity. Surgical resection and orthotopic liver transplantation have curative potential, but fewer than 20% of patients are suitable candidates. Interventional treatments are offered to the vast majority of patients. Radiofrequency (RFA) and microwave ablation (MWA) are among the therapeutic modalities, with similar indications which include the presence of up to three lesions, smaller than 3 cm in size, and the absence of extrahepatic disease. The therapeutic effect of both methods relies on thermal injury, but MWA uses an electromagnetic field as opposed to electrical current used in RFA. Unlike MWA, the effect of RFA is partially limited by the heat-sink effect and increased impedance of the ablated tissue. Compared with RFA, MWA attains a more predictable ablation zone, permits simultaneous treatment of multiple lesions, and achieves larger coagulation volumes in a shorter procedural time. Major complications of both methods are comparable and infrequent (approximately 2%-3%), and they include haemorrhage, infection/abscess, visceral organ injury, liver failure, and pneumothorax. RFA may incur the additional complication of skin burns. Nevertheless, there is no compelling evidence for differences in clinical outcomes, including local recurrence rates and survival. PMID:26052394

  16. Percutaneous microwave ablation vs radiofrequency ablation in the treatment of hepatocellular carcinoma

    PubMed Central

    Poulou, Loukia S; Botsa, Evanthia; Thanou, Ioanna; Ziakas, Panayiotis D; Thanos, Loukas

    2015-01-01

    Hepatocellular cancer ranks fifth among cancers and is related to chronic viral hepatitis, alcohol abuse, steatohepatitis and liver autoimmunity. Surgical resection and orthotopic liver transplantation have curative potential, but fewer than 20% of patients are suitable candidates. Interventional treatments are offered to the vast majority of patients. Radiofrequency (RFA) and microwave ablation (MWA) are among the therapeutic modalities, with similar indications which include the presence of up to three lesions, smaller than 3 cm in size, and the absence of extrahepatic disease. The therapeutic effect of both methods relies on thermal injury, but MWA uses an electromagnetic field as opposed to electrical current used in RFA. Unlike MWA, the effect of RFA is partially limited by the heat-sink effect and increased impedance of the ablated tissue. Compared with RFA, MWA attains a more predictable ablation zone, permits simultaneous treatment of multiple lesions, and achieves larger coagulation volumes in a shorter procedural time. Major complications of both methods are comparable and infrequent (approximately 2%-3%), and they include haemorrhage, infection/abscess, visceral organ injury, liver failure, and pneumothorax. RFA may incur the additional complication of skin burns. Nevertheless, there is no compelling evidence for differences in clinical outcomes, including local recurrence rates and survival. PMID:26052394

  17. Non-ablative radio-frequency rejuvenation: a histological and bio-molecular report.

    PubMed

    Avantaggiato, A; Andreasi Bassi, M; Cura, F; Pascali, M; Carinci, F

    2016-01-01

    Radiofrequency machines for medical use are known to produce moderate clinical improvement of skin laxity without invasive procedures. Numerous equipment with different characteristics have been proposed after the introduction in 2002 of the first FDA approved device. This report is aimed to test if RF treatment is effective when performed at low frequency and low energy level. Two RF treatments were performed unilaterally 7 and 2 days before a planned eyebrow lifting surgery, with a radiofrequency device with 0.52 to 0.7 MHz frequencies, maximum energy of 200 W, used at 40% of its power. A bipolar handpiece with a diameter of 30 mm and a maximum power of 9-9.5 W was massaged along the temporal area for 10 min. Skin samples of treated and untreated sides were collected during surgery and processed for histologic examination and RT-PCR analysis, to test differences in gene activation in a panel of proteins that are relevant in extracellular matrix of dermal connective tissue. The histological examination of the samples showed that the treatment induced a loss of the typical oriented structure in the reticular dermis. The study through RT-PCR evidenced that ELN, the gene codifying for Elastine was strongly enhanced. Some collagen-tested genes (COL1A1, COL3A1 and COL9A1) were inhibited by the treatment, whereas COL2A1 and COL11 were activated. The genes responsible for Metallo-proteases (MMP) 2, 3 and 13 were depressed, while the MMP9 was stimulated. Gene codifying for Hyaluronic synthase 1 (HAS1), Hyluronidase 1 (HYAL1), Neutrophyl elastase (Elane), Desmoplakin (DSP) and GDF6 were inhibited. Insulin like growth factor (IGF1) gene activity was enhanced. RF treatment, with the tested non-ablative equipment, produced histological effects and change in DNA expression of some extracellular matrix related genes, confirming the biostimulatory role of this procedure. PMID:27469572

  18. Evaluation of the current radiofrequency ablation systems using axiomatic design theory.

    PubMed

    Zhang, Bing; Moser, Michael A J; Luo, Yigang; Zhang, Edwin M; Zhang, Wenjun

    2014-04-01

    This article evaluates current radiofrequency ablation systems using axiomatic design theory. Due to its minimally invasive procedure, short-time hospital stay, low cost, and tumour metastasis treatment, the radiofrequency ablation technique has been playing an important role in tumour treatment in recent decades. Although the radiofrequency ablation technique has many advantages, some issues still need to be addressed. Among these issues, the two most important are as follows: (1) the size of tumours to be removed (has to be larger than 3 cm in diameter) and (2) cleanness of the removal. Many device solutions have been proposed to address the two issues. However, there is a lack of knowledge regarding the systematic evaluation of these solutions. This article evaluates these systems in terms of their solution principles (or simply called conceptual design in general product design theory) using a design theory called axiomatic design theory. In addition, with the axiomatic design theory, a better conceptual design in terms of its feasibility to cope with incomplete target tissue necrosis from the large size of tumours has been found. The detailed analysis and simulation of the new conceptual design are conducted using finite element approach. The results in this article are proved by the information of animal experiments and clinical practices obtained from the literature. This study thus contributes to the current knowledge to further developments in radiofrequency ablation systems and procedure guidelines for physicians to perform the radiofrequency ablation operation more effectively. PMID:24705341

  19. Reduction of electronic noise from radiofrequency generator during radiofrequency ablation in interventional MRI.

    PubMed

    Oshiro, Thomas; Sinha, Usha; Lu, David; Sinha, Shantanu

    2002-01-01

    MRI has been used increasingly in the recent past for the guidance and monitoring of minimally invasive interventional procedures, using typically radiofrequency (RF) and laser energy, cryoablation, and percutaneous ethanol. RF energy has been used over the last 30 years for the ablation of tissues. Its use in conjunction with MRI for monitoring is limited, however, because of the electronic noise produced by the RF generators, which can significantly deteriorate image quality. The objective of this work was to devise methods by which this noise can be reduced to an acceptable level to allow simultaneous acquisition of MR images for monitoring purposes with the application of RF energy. Three different methods of noise reduction were investigated in a 0.2 T MR scanner: filtration using external hardware circuitry, MR scanner software-controlled filtration, and keyholing. The last two methods were unable by themselves to suppress the noise to an acceptable degree. Hardware filtration, however, provides excellent suppression of RF noise and is able to withstand up to 12 W of RF energy. When all the three approaches are combined, significant reduction of RF noise is achieved. The feasibility of creating an RF lesion of about 1.2 cm diameter in vivo in a porcine model simultaneously with temperature-sensitive MRI with adequate noise suppression is demonstrated. PMID:11884792

  20. Case 222: Pericardioesophageal Fistula after Cardiac Radiofrequency Ablation.

    PubMed

    Miller, Joseph M; Sukov, Richard J

    2015-10-01

    History A 56-year-old woman presented to the emergency department after a cross-country flight. While in flight, she experienced sudden onset of epigastric and midsternal chest pain with shortness of breath. Her symptoms improved markedly after she received oxygen on board, and she finished the flight without further incident. Once home later that night, the pain recurred, and she was taken to the hospital. Her history included chronic pain syndrome, hypertension, and refractory paroxysmal atrial fibrillation, for which she had undergone radiofrequency ablation on two occasions. Her most recent ablation was 1 month prior. Upon arrival in the emergency department, her vital signs were within normal limits, and an electrocardiogram was unchanged from baseline. A chest radiograph obtained at the time of physical examination was unchanged from baseline. Given her recent travel history, there was suspicion for a pulmonary embolism. Ventilation-perfusion imaging and lower extremity Doppler ultrasonography were performed (images not shown) and revealed no evidence of pulmonary embolism or lower extremity thrombus. Because of the patient's clinical stability and because her symptoms had improved, she declined admission for observation and returned home against medical advice. The patient returned to the emergency department 2 days later in severe distress, with unstable vital signs, a jaundiced appearance, and substantial pain in her chest and abdomen. Her creatinine level was 4.4 mg/dL (388.9 μmol/L) (increased from 0.9 mg/dL [79.6 μmol/L] 2 days prior). Frontal and lateral radiographs of the chest were obtained and indicated increasing pericardial effusion. Bedside echocardiography enabled confirmation of these radiographic findings, and pericardiocentesis was performed. The patient's condition immediately improved, and she was admitted to the cardiac intensive care unit. Her symptoms recurred 3 days later, and a pericardial drain was placed. Fluid cultures were

  1. Single-Session Radiofrequency Ablation of Bilateral Lung Metastases

    SciTech Connect

    Palussiere, Jean Gomez, Fernando; Cannella, Matthieu; Ferron, Stephane; Descat, Edouard; Fonck, Marianne; Brouste, Veronique; Avril, Antoine

    2012-08-15

    Purpose: This retrospective study examined the feasibility and efficacy of bilateral lung radiofrequency ablation (RFA) performed in a single session. Methods: From 2002-2009, patients with bilateral lung metastases were treated by RFA, where possible in a single session under general anesthesia with CT guidance. The second lung was punctured only if no complications occurred after treatment of the first lung. Five lung metastases maximum per patient were treated by RFA and prospectively followed. The primary endpoint was the evaluation of acute and delayed complications. Secondary endpoints were calculation of hospitalization duration, local efficacy, median survival, and median time to tumor progression. Local efficacy was evaluated on CT or positron emission tomography (PET) CT. Results: Sixty-seven patients were treated for bilateral lung metastases with RFA (mean age, 62 years). Single-session treatment was not possible in 40 due to severe pneumothoraces (n = 24), bilateral pleural contact (n = 14), and operational exclusions (n = 2). Twenty-seven (41%) received single-session RFA of lesions in both lungs for 66 metastases overall. Fourteen unilateral and four bilateral pneumothoraces occurred (18 overall, 66.7%). Unilateral (n = 13) and bilateral (n = 2) chest tube drainage was required. Median hospitalization was 3 (range, 2-8) days. Median survival was 26 months (95% confidence interval (CI), 19-33). Four recurrences on RFA sites were observed (4 patients). Median time to tumor progression was 9.5 months (95% CI, 4.2-23.5). Conclusions: Although performing single-session bilateral lung RFA is not always possible due to pneumothoraces after RFA of first lung, when it is performed, this technique is safe and effective.

  2. Laparoscopic Radiofrequency Fibroid Ablation: Phase II and Phase III Results

    PubMed Central

    Pemueller, Rodolfo Robles; Garza Leal, José Gerardo; Abbott, Karen R.; Falls, Janice L.; Macer, James

    2014-01-01

    Background and Objectives: To review phase II and phase III treatments of symptomatic uterine fibroids (myomas) using laparoscopic radiofrequency volumetric thermal ablation (RFVTA). Methods: We performed a retrospective, multicenter clinical analysis of 206 consecutive cases of ultrasound-guided laparoscopic RFVTA of symptomatic myomas conducted on an outpatient basis under two phase II studies at 2 sites (n = 69) and one phase III study at 11 sites (n = 137). Descriptive and exploratory, general trend, and matched-pair analyses were applied. Results: From baseline to 12 months in the phase II study, the mean transformed symptom severity scores improved from 53.9 to 8.8 (P < .001) (n = 57), health-related quality-of-life scores improved from 48.5 to 92.0 (P < .001) (n = 57), and mean uterine volume decreased from 204.4 cm3 to 151.4 cm3 (P = .008) (n = 58). Patients missed a median of 4 days of work (range, 2–10 days). The rate of possible device-related adverse events was 1.4% (1 of 69). In the phase III study, approximately 98% of patients were assessed at 12 months, and their transformed symptom severity scores, health-related quality-of-life scores, mean decrease in uterine volume, and mean menstrual bleeding reduction were also significant. Patients in phase III missed a median of 5 days of work (range, 1–29 days). The rate of periprocedural device-related adverse events was 3.5% (5 of 137). Despite the enrollment requirement for patients in both phases to have completed childbearing, 4 pregnancies occurred within the first year after treatment. Conclusions: RFVTA does not require any uterine incisions and provides a uterine-sparing procedure with rapid recovery, significant reduction in uterine size, significant reduction or elimination of myoma symptoms, and significant improvement in quality of life. PMID:24960480

  3. Radiofrequency Ablation of Hepatocellular Cancer in 110 Patients With Cirrhosis

    PubMed Central

    Curley, Steven A.; Izzo, Francesco; Ellis, Lee M.; Nicolas Vauthey, J.; Vallone, Paolo

    2000-01-01

    Objective To determine the treatment efficacy, safety, local tumor control, and complications related to radiofrequency ablation (RFA) in patients with cirrhosis and unresectable hepatocellular carcinoma (HCC). Summary Background Data Most patients with HCC are not candidates for resection because of tumor size, location, or hepatic dysfunction related to cirrhosis. RFA is a technique that permits in situ destruction of tumors by means of local tissue heating. Methods One hundred ten patients with cirrhosis and HCC (Child class A, 50; B, 31; C, 29) were treated during a prospective study using RFA. Patients were treated with RFA using an open laparotomy, laparoscopic, or percutaneous approach with ultrasound guidance to place the RF needle electrode into the hepatic tumors. All patients were followed up at regular intervals to detect treatment-related complications or recurrence of disease. Results All 110 patients were followed up for at least 12 months after RFA (median follow-up 19 months). Percutaneous or intraoperative RFA was performed in 76 (69%) and 34 patients (31%), respectively. A total of 149 discrete HCC tumor nodules were treated with RFA. The median diameter of tumors treated percutaneously (2.8 cm) was smaller than that of lesions treated during laparotomy (4.6 cm). Local tumor recurrence at the RFA site developed in four patients (3.6%); recurrent HCC subsequently developed in other areas of the liver in all four. New liver tumors or extrahepatic metastases developed in 50 patients (45.5%), but 56 patients (50.9%) had no evidence of recurrence. There were no treatment-related deaths, but complications developed in 14 patients (12.7%) after RFA. Conclusions In patients with cirrhosis and HCC, RFA produces effective local control of disease in a significant proportion of patients and can be performed safely with minimal complications. PMID:10973388

  4. Radiofrequency Ablation of Unresectable Primary and Metastatic Hepatic Malignancies

    PubMed Central

    Curley, Steven A.; Izzo, Francesco; Delrio, Paolo; Ellis, Lee M.; Granchi, Jennifer; Vallone, Paolo; Fiore, Francesco; Pignata, Sandro; Daniele, Bruno; Cremona, Francesco

    1999-01-01

    Objective To describe the safety and efficacy of radiofrequency ablation (RFA) to treat unresectable malignant hepatic tumors in 123 patients. Background The majority of patients with primary or metastatic malignancies confined to the liver are not candidates for resection because of tumor size, location, or multifocality or inadequate functional hepatic reserve. Local application of heat is tumoricidal; therefore, the authors investigated a novel RFA system to treat patients with unresectable hepatic cancer. Patients and Methods Patients with hepatic malignancies were entered into a prospective, nonrandomized trial. The liver tumors were treated percutaneously or during surgery under ultrasound guidance using a novel LeVeen monopolar array needle electrode and an RF 2000 generator. All patients were followed to assess complications, treatment response, and recurrence of malignant disease. Results RFA was used to treat 169 tumors (median diameter 3.4 cm, range 0.5 to 12 cm) in 123 patients. Primary liver cancer was treated in 48 patients (39.1%), and metastatic liver tumors were treated in 75 patients (60.9%). Percutaneous and intraoperative RFA was performed in 31 patients (35.2%) and 92 patients (74.8%), respectively. There were no treatment-related deaths, and the complication rate after RFA was 2.4%. All treated tumors were completely necrotic on imaging studies after completion of RFA treatments. With a median follow-up of 15 months, tumor has recurred in 3 of 169 treated lesions (1.8%), but metastatic disease has developed at other sites in 34 patients (27.6%). Conclusions RFA is a safe, well-tolerated, and effective treatment to achieve tumor destruction in patients with unresectable hepatic malignancies. Because patients are at risk for the development of new metastatic disease after RFA, multimodality treatment approaches that include RFA should be investigated. PMID:10400029

  5. Radiofrequency ablation as treatment for pulmonary metastasis of colorectal cancer

    PubMed Central

    Hiraki, Takao; Gobara, Hideo; Iguchi, Toshihiro; Fujiwara, Hiroyasu; Matsui, Yusuke; Kanazawa, Susumu

    2014-01-01

    Radiofrequency ablation (RFA) causes focal coagulation necrosis in tissue. Its first clinical application was reported in 2000, and RFA has since been commonly used in both primary and metastatic lung cancer. The procedure is typically performed using computed tomography guidance, and the techniques for introducing the electrode to the tumor are simple and resemble those used in percutaneous lung biopsy. The most common complication is pneumothorax, which occurs in up to 50% of procedures; chest tube placement for pneumothorax is required in up to 25% of procedures. Other severe complications, such as pleural effusion requiring chest tube placement, infection, and nerve injury, are rare. The local efficacy depends on tumor size, and local progression after RFA is not rare, occurring in 10% or more of patients. The local progression rate is particularly high for tumors > 3 cm. Repeat RFA may be used to treat local progression. Short- to mid-term survival after RFA appears promising and is approximately 85%-95% at 1 year and 45%-55% at 3 years. Long-term survival data are sparse. Better survival may be expected for patients with small metastasis, low carcinoembryonic antigen levels, and/or no extrapulmonary metastasis. The notable advantages of RFA are that it is simple and minimally invasive; preserves pulmonary function; can be repeated; and is applicable regardless of previous treatments. Its most substantial limitation is limited local efficacy. Although surgery is still the method of choice for treatment with curative intent, the ultimate application of RFA may be to replace metastasectomy for small metastases. Randomized trials comparing RFA with surgery are needed. PMID:24574771

  6. [Radiofrequency ablation in tachycardias due to accessory pathways in a pediatric population].

    PubMed

    Iturralde, P; Saucedo, J; Colín, L; Kershenovich, S; Robledo, R; Garrido, A; González-Hermosillo, J A; Buendía, A

    1994-01-01

    Catheter ablation of accessory atrioventricular pathways using radiofrequency current was attempted in 61 children and young adolescents less than 18 years of age who were referred for treatment of symptomatic supraventricular tachycardia. Thirty-three children had the Wolff-Parkinson-White syndrome and 30 tachyarrhythmias related to an accessory pathway conducting only in retrograde fashion. Ablation of left sided accessory pathways was usually attempted utilizing an arterial approach to the annulus of the mitral valve, only in one case we used the transseptal approach, while the venous route to the atrial aspect of the tricuspid valvular annulus was chosen for right sided accessory connections. Ablation of 55 of 63 accessory connections was achieved (87% success) with a range of 1 to 42 applications of radiofrequency current. The sessions were completed within 19 to 180 minutes, and we used within 16 to 45 watts of radiofrequency current. Two patients had complications as a result of their ablation procedure. One patient had complete heart block but did not require pacemaker implantation, and other one had mitral regurgitation. A second session was necessary in three patients, two of three accessory pathways were ablated, giving a success rate of 90%. During a one year period of follow-up, we had 4 recurrences (7.2%). Catheter ablation using radiofrequency current is a highly effective and safe curative approach for treating young patients with supraventricular tachycardia mediated by accessory pathways. PMID:7840718

  7. Use of Hydrodissection to Prevent Nerve and Muscular Damage during Radiofrequency Ablation of Kidney Tumors

    PubMed Central

    Lee, S. Justin; Choyke, Lynda T.; Locklin, Julia K.; Wood, Bradford J.

    2008-01-01

    Muscular complications are uncommon but have been reported after radiofrequency (RF) ablation of renal tumors. Ablation of renal lesions near the psoas muscle may result in paresthesia in the distribution of the genitofemoral nerve. The present report describes a case of sensory and muscular dysfunction after RF ablation of a renal lesion lying on top of the psoas muscle that was treated without hydrodissection. To prevent this complication, hydrodissection was effectively used in two other patients during RF ablation of lesions abutting or in close proximity to the psoas muscle. PMID:17185695

  8. Transcatheter Arterial Embolization for Tumor Seeding in the Chest Wall After Radiofrequency Ablation for Hepatocellular Carcinoma

    SciTech Connect

    Shibata, Toshiya Shibata, Toyomichi; Maetani, Yoji; Kubo, Takeshi; Nishida, Naoshi; Itoh, Kyo

    2006-06-15

    Tumor seeding in the chest wall was depicted at follow-up CT obtained 9 months after radiofrequency ablation for hepatocellular carcinoma. Transcatheter arterial embolization was successfully performed, injecting emulsion of 10 mg of epirubicin and 1 ml of iodized oil followed by gelatin sponge particles via the microcatheter placed in the right eleventh intercostal artery. The patient died of tumor growth in the liver one year after the embolization, but no progression of the tumor seeding was noted during the follow-up period. We conclude that transcatheter arterial embolization was effective for the control of tumor seeding after radiofrequency ablation for hepatocellular carcinoma.

  9. Combined MRI and Fluoroscopic Guided Radiofrequency Ablation of a Renal Tumor

    SciTech Connect

    Fotiadis, Nikolas I.; Sabharwal, Tarun; Gangi, Afshin; Adam, Andreas

    2009-01-15

    Percutaneous CT- and ultrasound-guided radiofrequency ablation of renal cell carcinoma (RCC) has been shown to have very promising medium-term results. We present a unique case of recurrent RCC after partial nephrectomy in a patient with a single kidney and impaired renal function. This tumor could not be visualized either with CT or with ultrasound. A combination of magnetic resonance imaging and fluoroscopic guidance was used, to the best of our knowledge for the first time, to ablate the tumor with radiofrequency. The patient was cancer-free and off dialysis at 30-month follow up.

  10. Temperature profiles of 980- and 1,470-nm endovenous laser ablation, endovenous radiofrequency ablation and endovenous steam ablation.

    PubMed

    Malskat, W S J; Stokbroekx, M A L; van der Geld, C W M; Nijsten, T E C; van den Bos, R R

    2014-03-01

    Endovenous thermal ablation (EVTA) techniques are very effective for the treatment of varicose veins, but their exact working mechanism is still not well documented. The lack of knowledge of mechanistic properties has led to a variety of EVTA protocols and a commercially driven dissemination of new or modified techniques without robust scientific evidence. The aim of this study is to compare temperature profiles of 980-and 1,470-nm endovenous laser ablation (EVLA), segmental radiofrequency ablation (RFA), and endovenous steam ablation (EVSA). In an experimental setting, temperature measurements were performed using thermocouples; raw potato was used to mimic a vein wall. Two laser wavelengths (980 and 1,470 nm) were used with tulip-tip fibers and 1,470 nm also with a radial-emitting fiber. Different powers and pullback speeds were used to achieve fluences of 30, 60, and 90 J/cm. For segmental RFA, 1 cycle of 20 s was analyzed. EVSA was performed with two and three pulses of steam per centimeter. Maximum temperature increase, time span of relevant temperature increase, and area under the curve of the time of relevant temperature increase were measured. In all EVLA settings, temperatures increased and decreased rapidly. High fluence is associated with significantly higher temperatures and increased time span of temperature rise. Temperature profiles of 980- and 1,470-nm EVLA with tulip-tip fibers did not differ significantly. Radial EVLA showed significantly higher maximum temperatures than tulip-tip EVLA. EVSA resulted in mild peak temperatures for longer durations than EVLA. Maximum temperatures with three pulses per centimeter were significantly higher than with two pulses. RFA temperature rises were relatively mild, resulting in a plateau-shaped temperature profile, similar to EVSA. Temperature increase during EVLA is fast with a high-peak temperature for a short time, where EVSA and RFA have longer plateau phases and lower maximum temperatures. PMID

  11. Radiofrequency ablation: a safe and economical modality in treatment of Brooke-Spiegler syndrome.

    PubMed

    Chaudhary, Savita; Dayal, Surabhi

    2012-08-01

    Brooke-Spiegler syndrome is an uncommon disease. Patients have a predisposition to develop cutaneous adnexal neoplasms such as cylindromas, trichoepitheliomas, spiradenomas, trichoblastomas, basal cell carcinomas, follicular cysts, and organoid nevi. Malignant transformation of preexisting tumors also occurs in these individuals. Various techniques have been used for the treatment of trichoepitheliomas and cylindromas including excision, electrocautery, carbon dioxide laser ablation, cryosurgery, and radiotherapy. In our case, cylindromas were ablated by radiofrequency in multiple sittings. Trichoepitheliomas were ablated using coagulation mode with power # 3 to 3.5. Cosmetically acceptable results were obtained in 100 percent of the cylindromas and 70 percent of the trichoepitheliomas (Visual Analog Scale). The radiofrequency ablation technique under different modes can be used in both large tumors as well as smaller ones, especially in developing countries because it is very cost effective and easily accessible. PMID:22948057

  12. The Research of Feasibility and Efficacy of Radiofrequency Ablation in Treating Uterine Fibroids.

    PubMed

    Luo, Xin; Shu, Shan-Rong; Ma, Xue-Feng; Shuai, Han-Lin

    2015-11-01

    To explore the feasibility and efficacy of radiofrequency ablation in treating uterine fibroids.Ninety patients with multiple uterine fibroids, who had undergone hysterectomy were included in the study. After the uterus was resected, the temperature of 60, 80, 100°C were adopted to ablate the in vitro fibroid with each temperature dealing with 30 patients. Simultaneously, 5 patients were included, whose in vivo fibroid were ablated with the temperature of 100°C before the fibroids were removed after laparotomy. After the fibroids were ablated, the smooth muscle in the ablated center (group A), the ablated edge (group B) and 1 cm away from the ablated edge (group C) were taken. Then, the samples were stained with hematoxylin and eosin (HE) to examine the histopathological changes, and immunohistochemistry was performed to detect the expression of estrogen receptor (ER) and progesterone receptor (PR).After radiofrequency ablation, the ablated lesions were round, toast tan, and dry on gross appearance. There were no obvious tissue carbonization and there were distinct boundary from periphery tissue. In vitro: On automated analysis, the average optical density of ER and PR in group A, B, and C was lower than the control group (P < 0.05), and which were gradually raised with the increased distance to electrode. In the same treatment group, ER optical density was gradually decreased with the increased temperature among 3 different groups. The PR optical density was decreased with the increased temperature under different temperatures in group A and group B, there was significant difference among groups (P < 0.05). But in group C, there was no difference in PR expression among the temperature of 60, 80, and 100°C (P > 0.05). In vivo: Compared with the control group, the average optical density of ER and PR were significantly different among group A, B, and C (P < 0.05), what's more, it was gradually raised with the increased distance to electrode.After radiofrequency

  13. Percutaneous Intraductal Radiofrequency Ablation for Clearance of Occluded Metal Stent in Malignant Biliary Obstruction: Feasibility and Early Results

    SciTech Connect

    Pai, Madhava; Valek, Vlastimil; Tomas, Andrasina; Doros, Attila; Quaretti, Pietro; Golfieri, Rita; Mosconi, Cristina; Habib, Nagy

    2013-07-11

    PurposeThe major complication occurring with biliary stents is stent occlusion, frequently seen because of tumour in-growth, epithelial hyperplasia, and sludge deposits, resulting in recurrent jaundice and cholangitis. We report a prospective study with the results of first in man percutaneous intraductal radiofrequency (RF) ablation to clear the blocked metal stents in patients with malignant biliary obstruction using a novel bipolar RF catheter.MethodsNine patients with malignant biliary obstruction and blocked metal stents were included. These patients underwent intraductal biliary RF ablation through the blocked metal stent following external biliary decompression with an internal–external biliary drainage.ResultsAll nine patients had their stent patency restored successfully without the use of secondary stents. Following this intervention, there was no 30-day mortality, haemorrhage, bile duct perforation, bile leak, or pancreatitis. Of the nine patients, six are alive and three patients are dead with a median follow-up of 122 (range 50–488) days and a median stent patency of 102.5 (range 50–321) days. Six patients had their stent patent at the time of last follow-up or death. Three patients with stent blockage at 321, 290, and 65 days postprocedure underwent percutaneous transhepatic drain insertion and repeat ablation.ConclusionsIn this selective group of patients, it appears that this new approach is safe and feasible. Efficacy remains to be proven in future, randomized, prospective studies.

  14. Sharp Potential in Cavo-tricuspid Isthmus Targeted during Typical Atrial Flutter Radiofrequency Ablation.

    PubMed

    Rey, Florian; Sunthorn, Henri

    2016-03-01

    The aim of this study was to define atrial electrograms (EGM) morphology, which could predict a conduction gap in cavo-tricuspid isthmus (CTI) during typical atrial flutter (AF) radiofrequency ablation. One hundred atrial EGM were retrospectively analysed. We demonstrated that recognising a sharp potential (short duration and high amplitude) is useful for quickly achieving CTI bi-directional block during typical AF ablation. PMID:26700023

  15. Injection of Subphrenic Saline During Radiofrequency Ablation to Minimize Diaphragmatic Injury

    SciTech Connect

    Kapoor, Baljendra S.; Hunter, David W.

    2003-06-15

    An 82-year-old man with a history of colorectal cancer presented with metastatic disease to the liver (Couinaud segment 8). We describe the techniques that we employed to successfully perform radiofrequency ablation of a liver metastasis near the dome of the diaphragm utilizing subphrenic infusion of normal saline. The aim of this technique was to prevent thermal injury of the diaphragm.

  16. Stress (Tako-Tsubo) Cardiomyopathy Following Radiofrequency Ablation of a Liver Tumor: A Case Report

    SciTech Connect

    Joo, Ijin; Lee, Jeong Min Han, Joon Koo; Choi, Byung Ihn; Park, Eun-Ah

    2011-02-15

    Stress cardiomyopathy is characterized by transient left ventricular dysfunction occurring in the absence of obstructive coronary disease. It is precipitated by acute emotional or physical stress. We present a case of stress cardiomyopathy which developed during hepatic radiofrequency ablation of hepatocellular carcinoma.

  17. Reversibility of tachycardia-induced cardiomyopathy after radiofrequency ablation of incessant supraventricular tachycardia in infants.

    PubMed Central

    Sanchez, C.; Benito, F.; Moreno, F.

    1995-01-01

    Tachycardia-induced cardiomyopathy developed in a 3 month old infant with permanent junctional reciprocating tachycardia, which was incessant despite medical treatment. The patient underwent transcatheter radiofrequency ablation. There were no complications and 8 months after the procedure the patient was symptom free without medication. Images PMID:7547032

  18. Comparison between retrograde and transeptal approach in radiofrequency catheter ablation of left accessory pathways.

    PubMed

    Hashem, S; Choudhury, A K; Paul, G K; Rahman, M Z

    2015-01-01

    To study a series of patients submitted to radiofrequency catheter ablation (RFA) of left accessory pathways (AP) using the transeptal approach (TSA) as compared to the conventional retrograde arterial approach (RAA). Sixty consecutive patients (44 male; mean age of 35.60±11.63 years) with 60 left APs (39 overt and 21 concealed) underwent catheter ablation using the TS method (30 patients) and the RAA method (30 patients) in an alternate fashion. The analysis was performed according to the intention-to-treat principle. The transeptal puncture was successfully performed in 29 patients (96%). This access allowed primary success in the ablation in all the patients without any complication. When we compared this approach with the RAA there was no difference as regards the primary success (p=0.103), fluoroscopy time (p=0.565) and total time (p=0.1917). Three patients in the RAA group presented a vascular complication. The TSA allowed shorter ablation times (p=0.006) and smaller number of radiofrequency applications (p=0.042) as compared to the conventional RAA. The patients who had unsuccessful ablation in the first session in each approach underwent with the opposite technique (cross-over), with a final ablation success rate of 100%.The TS and RA approaches showed similar efficacy and safety for the ablation of left accessory pathways. The TSA allowed shorter ablation times and smaller number of radiofrequency applications. When the techniques were used in a complementary fashion, they increased the final efficacy of the ablation. PMID:25725674

  19. Radiofrequency catheter ablation of the atrioventricular junction from the left ventricle

    SciTech Connect

    Sousa, J.; el-Atassi, R.; Rosenheck, S.; Calkins, H.; Langberg, J.; Morady, F. )

    1991-08-01

    The purpose of this study was to describe a new technique for catheter ablation of the atrioventricular junction using radiofrequency energy delivered in the left ventricle. Catheter ablation of the atrioventricular (AV) junction using a catheter positioned across the tricuspid annulus was unsuccessful in eight patients with a mean {plus minus} SD age of 51 {plus minus} 19 years who had AV nodal reentry tachycardia (three patients), orthodromic tachycardia using a concealed midseptal accessory pathway, atrial tachycardia, atrial flutter (two patients), or atrial fibrillation. Before attempts at catheter ablation of the AV junction, each patient had been refractory to pharmacological therapy, and four had failed attempts at either catheter modification of the AV node using radiofrequency energy or surgical and catheter ablation of the accessory pathway. Conventional right-sided catheter ablation of the AV junction using radiofrequency energy in six patients and both radiofrequency energy and direct current shocks in two patients was ineffective. The mean amplitude of the His bundle potential recorded at the tricuspid annulus at the sites of unsuccessful AV junction ablation was 0.1 {plus minus} 0.08 mV, with a maximum His amplitude of 0.03-0.28 mV. A 7F deflectable-tip quadripolar electrode catheter with a 4-mm distal electrode was positioned against the upper left ventricular septum using a retrograde aortic approach from the femoral artery. Third-degree AV block was induced in each of the eight patients with 20-36 W applied for 15-30 seconds. The His bundle potential at the sites of successful AV junction ablation ranged from 0.06 to 0.99 mV, with a mean of 0.27 {plus minus} 0.32 mV. There was no rise in the creatine kinase-MB fraction and no complications occurred. An intrinsic escape rhythm of 30-60 beats/min was present in seven of the eight patients.

  20. Successful treatment of hepatic oligometastases with stereotactic ablative radiotherapy and radiofrequency ablation in an anaplastic lymphoma kinase fusion-positive lung cancer patient.

    PubMed

    Weber, Britta; Liu, Mitchell; Sobkin, Paul; Morris, Stephan W; Hout, David; van der Westhuizen, Nicholas; Tonseth, R Petter; Saltman, David L

    2016-03-01

    Local ablative therapy with stereotactic ablative radiotherapy may improve survival in oncogene-addicted lung cancer patients with extracranial oligometastatic disease treated with targeted therapies. There is limited data on the use of radiofrequency ablation (RFA) in this same setting. We present a case of an anaplastic lymphoma kinase (ALK)-positive lung cancer patient with hepatic oligometastatic progression who was successfully treated with both stereotactic ablative radiation and RFA while continuing with an ALK inhibitor. PMID:27087977

  1. Pulsed Radiofrequency Ablation Under Ultrasound Guidance for Huge Neuroma

    PubMed Central

    Jung, Il; Lee, Chang Hee; Kim, Se Hun; Kim, Jin Sun; Yoo, Byoung Woo

    2014-01-01

    Amputation neuroma can cause very serious, intractable pain. Many treatment modalities are suggested for painful neuroma. Pharmacologic treatment shows a limited effect on eliminating the pain, and surgical treatment has a high recurrence rate. We applied pulsed radiofrequency treatment at the neuroma stalk under ultrasonography guidance. The long-term outcome was very successful, prompting us to report this case. PMID:25031817

  2. Radiofrequency Ablation for the Treatment of Hepatocellular Carcinoma in Patients with Transjugular Intrahepatic Portosystemic Shunts

    SciTech Connect

    Park, Jonathan K.; Al-Tariq, Quazi Z.; Zaw, Taryar M. Raman, Steven S. Lu, David S.K.

    2015-10-15

    PurposeTo assess radiofrequency (RF) ablation efficacy, as well as the patency of transjugular intrahepatic portosystemic shunts (TIPSs), in patients with hepatocellular carcinoma (HCC).Materials and MethodsRetrospective database review of patients with pre-existing TIPS undergoing RF ablation of HCC was conducted over a 159-month period ending in November 2013. TIPS patency pre- and post-RF ablation was assessed by ultrasound, angiography, and/or contrast-enhanced CT or MRI. Patient demographics and immediate post-RF ablation outcomes and complications were also reviewed.Results19 patients with 21 lesions undergoing 25 RF ablation sessions were included. Child-Pugh class A, B, and C scores were seen in 1, 13, and 5 patients, respectively. Eleven patients (58 %) ultimately underwent liver transplantation. Immediate technical success was seen in all ablation sessions without residual tumor enhancement (100 %). No patients (0 %) suffered liver failure within 1 month of ablation. Pre-ablation TIPS patency was demonstrated in 22/25 sessions (88 %). Of 22 cases with patent TIPS prior to ablation, post-ablation patency was demonstrated in 22/22 (100 %) at immediate post-ablation imaging and in 21/22 (95 %) at last follow-up (1 patient was incidentally noted to have occlusion 31 months later). No immediate complications were observed.ConclusionAblation efficacy was similar to the cited literature values for patients without TIPS. Furthermore, TIPS patency was preserved in the majority of cases. Patients with both portal hypertension and HCC are not uncommonly encountered, and a pre-existing TIPS does not appear to be a definite contraindication for RF ablation.

  3. [The radiofrequency ablation of accessory pathways in 100 consecutive patients with supraventricular tachycardias].

    PubMed

    Colín, L; Kershenovich, S; Iturralde, P; Dan, L; Martínez Ríos, M A; Casanova, M; González Hermosillo, J A

    1993-01-01

    The purpose of this study is to describe the results and the complications of radiofrequency catheter ablation, of accessory pathways in 100 consecutive patients. We had one patient with two pathways. Of the 101 accessory pathways, 56 were overt and 45 concealed. Only 19 patients have had a previous electrophysiology study, in the others, the study and the ablation were performed simultaneously. The location of the accessory pathways were as follows: 61 pathways in the free wall of the left ventricle, 4 in the free wall of the right ventricle, 25 in the left posteroseptal region, 9 in the right posteroseptal region and 2 in the right anteroseptal area. The time required for the diagnostic component of the electrophysiology study, the ablation procedure and the fluoroscopic time was recorded for each patient. Ninety-one of 101 accessory AV connections were successfully ablated (90%). Our success rate for the initial attempt was 87%. We had the opportunity to do a second attempt in only 4 out of 14 patients. The mean time of the procedure, including the electrophysiology test and the ablation was 95.6 %/-55.3 minutes. We have had a recurrence of 9% and 4% of non fatal complications. Radiofrequency catheter ablation can be performed safely and with a high success rate. PMID:8466365

  4. Percutaneous Radiofrequency Lung Ablation Combined with Transbronchial Saline Injection: An Experimental Study in Swine

    SciTech Connect

    Kawai, T. Kaminou, T. Sugiura, K.; Hashimoto, M.; Ohuchi, Y.; Adachi, A.; Fujioka, S.; Ito, H.; Nakamura, K.; Ihaya, T.; Ogawa, T.

    2010-02-15

    To evaluate the efficacy of radiofrequency lung ablation with transbronchial saline injection. The bilateral lungs of eight living swine were used. A 13-gauge bone biopsy needle was inserted percutaneously into the lung, and 1 ml of muscle paste was injected to create a tumor mimic. In total, 21 nodules were ablated. In the saline injection group (group A), radiofrequency ablation (RFA) was performed for 11 nodules after transbronchial saline injection under balloon occlusion with a 2-cm active single internally cooled electrode. In the control group (group B), conventional RFA was performed for 10 nodules as a control. The infused saline liquid showed a wedge-shaped and homogeneous distribution surrounding a tumor mimic. All 21 RFAs were successfully completed. The total ablation time was significantly longer (13.4 {+-} 2.8 min vs. 8.9 {+-} 3.5 min; P = 0.0061) and the tissue impedance was significantly lower in group A compared with group B (73.1 {+-} 8.8 {Omega} vs. 100.6 {+-} 16.6 {Omega}; P = 0.0002). The temperature of the ablated area was not significantly different (69.4 {+-} 9.1{sup o}C vs. 66.0 {+-} 7.9{sup o}C; P = 0.4038). There was no significant difference of tumor mimic volume (769 {+-} 343 mm{sup 3} vs. 625 {+-} 191 mm{sup 3}; P = 0.2783). The volume of the coagulated area was significantly larger in group A than in group B (3886 {+-} 1247 mm{sup 3} vs. 2375 {+-} 1395 mm{sup 3}; P = 0.0221). Percutaneous radiofrequency lung ablation combined with transbronchial saline injection can create an extended area of ablation.

  5. Electromagnetic Initiation and Propagation of Bipolar Radiofrequency Tissue Reactions via Invasive Non-Insulated Microneedle Electrodes.

    PubMed

    Na, Jongju; Zheng, Zhenlong; Dannaker, Christopher; Lee, Sang Eun; Kang, Jin-Soo; Cho, Sung Bin

    2015-01-01

    Radiofrequency (RF) energy can be emitted into the skin, either non- or invasively, via a monopolar mode that utilizes an active electrode and a grounded electrode or via a bipolar mode that employs two active electrodes. In this experimental study of RF tissue reactions, bipolar RF energy was emitted in vivo to micropig skin at varying microneedle penetration depths, signal amplitudes, and conduction times. Immediately after RF treatment, skin samples exhibited RF-induced coagulation columns of thermal injury, separately generated around each microneedle in the dermis. In ex vivo bovine liver tissue, the thermal coagulation columns were found to be concentrated maximally around the pointed tips of each electrode. After a RF conduction time of 2 seconds, the individual areas of thermal coagulation began to converge with neighboring RF-induced coagulation columns; the convergence of coagulation columns was found to start from the tips of neighboring electrodes. PMID:26563971

  6. Electromagnetic Initiation and Propagation of Bipolar Radiofrequency Tissue Reactions via Invasive Non-Insulated Microneedle Electrodes

    PubMed Central

    Na, Jongju; Zheng, Zhenlong; Dannaker, Christopher; Lee, Sang Eun; Kang, Jin-Soo; Cho, Sung Bin

    2015-01-01

    Radiofrequency (RF) energy can be emitted into the skin, either non- or invasively, via a monopolar mode that utilizes an active electrode and a grounded electrode or via a bipolar mode that employs two active electrodes. In this experimental study of RF tissue reactions, bipolar RF energy was emitted in vivo to micropig skin at varying microneedle penetration depths, signal amplitudes, and conduction times. Immediately after RF treatment, skin samples exhibited RF-induced coagulation columns of thermal injury, separately generated around each microneedle in the dermis. In ex vivo bovine liver tissue, the thermal coagulation columns were found to be concentrated maximally around the pointed tips of each electrode. After a RF conduction time of 2 seconds, the individual areas of thermal coagulation began to converge with neighboring RF-induced coagulation columns; the convergence of coagulation columns was found to start from the tips of neighboring electrodes. PMID:26563971

  7. Percutaneous Intraductal Radiofrequency Ablation is a Safe Treatment for Malignant Biliary Obstruction: Feasibility and Early Results

    SciTech Connect

    Mizandari, Malkhaz; Pai, Madhava Xi Feng; Valek, Vlastimil; Tomas, Andrasina; Quaretti, Pietro; Golfieri, Rita; Mosconi, Cristina; Ao Guokun; Kyriakides, Charis; Dickinson, Robert; Nicholls, Joanna; Habib, Nagy

    2013-06-15

    Purpose. Previous clinical studies have shown the safety and efficacy of this novel radiofrequency ablation catheter when used for endoscopic palliative procedures. We report a retrospective study with the results of first in man percutaneous intraductal radiofrequency ablation in patients with malignant biliary obstruction. Methods. Thirty-nine patients with inoperable malignant biliary obstruction were included. These patients underwent intraductal biliary radiofrequency ablation of their malignant biliary strictures following external biliary decompression with an internal-external biliary drainage. Following ablation, they had a metal stent inserted. Results. Following this intervention, there were no 30-day mortality, hemorrhage, bile duct perforation, bile leak, or pancreatitis. Of the 39 patients, 28 are alive and 10 patients are dead with a median survival of 89.5 (range 14-260) days and median stent patency of 84.5 (range 14-260) days. One patient was lost to follow-up. All but one patient had their stent patent at the time of last follow-up or death. One patient with stent blockage at 42 days postprocedure underwent percutaneous transhepatic drain insertion and restenting. Among the patients who are alive (n = 28) the median stent patency was 92 (range 14-260) days, whereas the patients who died (n = 10) had a median stent patency of 62.5 (range 38-210) days. Conclusions. In this group of patients, it appears that this new approach is feasible and safe. Efficacy remains to be proven in future, randomized, prospective studies.

  8. Comparison of Combination Therapies in the Management of Hepatocellular Carcinoma: Transarterial Chemoembolization with Radiofrequency Ablation versus Microwave Ablation

    PubMed Central

    Ginsburg, Michael; Zivin, Sean P.; Wroblewski, Kristen; Doshi, Taral; Vasnani, Raj J.; Van Ha, Thuong G.

    2015-01-01

    Purpose To compare retrospectively the outcomes and complications of transcatheter arterial chemoembolization with drug-eluting embolic agents combined with radiofrequency (RF) ablation or microwave (MW) ablation in treatment of hepatocellular carcinoma (HCC). Materials and Methods From 2003–2011, 89 patients with HCC received a combination therapy—transcatheter arterial chemoembolization plus RF ablation in 38 patients and transcatheter arterial chemoembolization plus MW ablation in 51 patients. Local tumor response, tumor progression-free survival (PFS), overall PFS, overall survival (OS), and complications were compared. Overall PFS and OS were compared between the two treatment groups in multivariate analysis controlling for Child-Pugh class, Barcelona Clinic Liver Classification stage, and index tumor size. Results Complete local tumor response was achieved in 37 (80.4%) of the tumors treated with transcatheter arterial chemoembolization plus RF ablation and 49 (76.6%) of the tumors treated with transcatheter arterial chemoembolization plus MW ablation (P = .67). The median tumor PFS and overall PFS were 20.8 months and 9.3 months (P = .72) for transarterial chemoembolization plus RF ablation and 21.8 months and 9.2 months for transarterial chemoembolization plus MW ablation (P = .32). The median OS of the transcatheter arterial chemoembolization plus RF ablation group was 23.3 months, and the median OS of the transcatheter arterial chemoembolization plus MW ablation group was 42.6 months, with no significant difference in the survival experience between the two groups (log-rank test, P = .10). In the multivariate analysis, Barcelona Clinic Liver Classification stage was the only factor associated with overall PFS and OS. One patient in the transcatheter arterial chemoembolization plus RF ablation cohort (3%) and two patients in the transcatheter arterial chemoembolization plus MW ablation cohort (4%) required prolonged hospitalization (< 48 h) for pain

  9. Survival after Radiofrequency Ablation in 122 Patients with Inoperable Colorectal Lung Metastases

    SciTech Connect

    Gillams, Alice; Khan, Zahid; Osborn, Peter; Lees, William

    2013-06-15

    Purpose. To analyze the factors associated with favorable survival in patients with inoperable colorectal lung metastases treated with percutaneous image-guided radiofrequency ablation. Methods. Between 2002 and 2011, a total of 398 metastases were ablated in 122 patients (87 male, median age 68 years, range 29-90 years) at 256 procedures. Percutaneous CT-guided cool-tip radiofrequency ablation was performed under sedation/general anesthesia. Maximum tumor size, number of tumors ablated, number of procedures, concurrent/prior liver ablation, previous liver or lung resection, systemic chemotherapy, disease-free interval from primary resection to lung metastasis, and survival from first ablation were recorded prospectively. Kaplan-Meier analysis was performed, and factors were compared by log rank test. Results. The initial number of metastases ablated was 2.3 (range 1-8); the total number was 3.3 (range 1-15). The maximum tumor diameter was 1.7 (range 0.5-4) cm, and the number of procedures was 2 (range 1-10). The major complication rate was 3.9 %. Overall median and 3-year survival rate were 41 months and 57 %. Survival was better in patients with smaller tumors-a median of 51 months, with 3-year survival of 64 % for tumors 2 cm or smaller versus 31 months and 44 % for tumors 2.1-4 cm (p = 0.08). The number of metastases ablated and whether the tumors were unilateral or bilateral did not affect survival. The presence of treated liver metastases, systemic chemotherapy, or prior lung resection did not affect survival. Conclusion. Three-year survival of 57 % in patients with inoperable colorectal lung metastases is better than would be expected with chemotherapy alone. Patients with inoperable but small-volume colorectal lung metastases should be referred for ablation.

  10. Electrophysiological Studies and Radiofrequency Ablations in Children and Adolescents with Arrhythmia

    PubMed Central

    Simão, Mariana Fernandez; Rios, Matheus Nardi; Leiria, Tiago Luiz Luz; Kruse, Marcelo Lapa; Pires, Leonardo Martins; SantAnna, Roberto Tofani; de Lima, Gustavo Glotz

    2015-01-01

    Background Radiofrequency ablation is the standard non-pharmacological treatment for arrhythmias in pediatric patients. However, arrhythmias and their associated causes have particular features in this population. Objective To analyze the epidemiological characteristics and findings of electrophysiological diagnostic studies and radiofrequency ablations in pediatric patients referred to the Electrophysiology Unit at Instituto de Cardiologia do Rio Grande do Sul, in order to characterize the particularities of this population. Methods Cross-sectional study with 330 electrophysiological procedures performed in patients aged less than 20 years between June 1997 and August 2013. Results In total, 330 procedures (9.6% of the overall procedures) were performed in patients aged less than 20 years (14.33 ± 3.25 years, age range 3 months to 19 years), 201 of which were males (60.9%). A total of 108 (32.7%) electrophysiological diagnostic studies were performed and of these, 48.1% showed abnormal findings. Overall, 219 radiofrequency ablations were performed (66.3%) with a success rate of 84.8%. The presence of an accessory pathway was the most prevalent finding, occurring in 158 cases (72.1%), followed by atrioventricular nodal reentrant tachycardia (16.8%), typical atrial flutter (3.1%) and extrasystoles originating from the right ventricular outflow tract (2.7%). Three patients developed complications during ablation (1.4%). Among congenital heart diseases, which occurred in 51 (15.4%) patients, atrial sept defect was the most frequent (27.4%), followed by ventricular sept defect (25.4%) and Ebstein's anomaly (17.6%). Conclusion Electrophysiological study and radiofrequency ablation are effective tools for diagnosis and treatment of arrhythmias in the pediatric population. PMID:25372472

  11. [A comparative study between surgical section and radiofrequency ablation of the anomalous pathways in the WPW syndrome].

    PubMed

    Iturralde, P; Colín, L; Kershenovich, S; Saucedo, J; de Micheli, A; Barragán, R; Martínez Rios, M A; González Hermosillo, J A

    1993-01-01

    Radiofrequency catheter ablation is an effective alternative to medical therapy to patient with Wolff Parkinson White syndrome (WPW). The purpose of this study is to compare our results in 70 patients with WPW that underwent either surgery or ablation procedure with radiofrequency energy. Of this number of patients the surgical procedure was successful in 82%; complications were present in 15% and mortality in 8%. Average hospitalization was 6 to 10 days and cost from 2 to 10 thousand of new pesos. On the other hand, of 44 patients that underwent radiofrequency ablation, in 80% the procedure was finally successful with recurrence of 9% and no mortality. The hospitalization period was one day, the cost run from 500 to 2 thousand of new pesos in our institution. These results demonstrate the efficacy of the radiofrequency energy ablation in the treatment of WPW. This procedure is safe and less expensive than surgery. PMID:8466362

  12. Thermal Ablation of Lung Tissue: In Vivo Experimental Comparison of Microwave and Radiofrequency

    SciTech Connect

    Crocetti, Laura Bozzi, Elena; Faviana, Pinuccia; Cioni, Dania; Della Pina, Clotilde; Sbrana, Alberto; Fontanini, Gabriella; Lencioni, Riccardo

    2010-08-15

    This study was designed to compare feasibility, safety, and effectiveness of microwave (MW) ablation versus radiofrequency (RF) ablation of lung tissue in a rabbit model. Twenty New Zealand White rabbits were submitted to MW (n = 10, group A) or RF ablation (n = 10, group B). The procedures were performed with a prototype MW ablation device with a 1.6-cm radiating section antenna (Valleylab MW Ablation System) and with a 2-cm exposed-tip RF electrode (Cool-tip RF Ablation System). At immediate computed tomography increase in density, maximum diameters (D1-D3) of ablation zones were measured and ablation volume was calculated. Histopathologic assessment was performed 3 and 7 days after the procedure. Technical success was achieved in nine of 10 rabbits in each group. One death occurred in group B. Complications included pneumothorax (group A, n = 4; group B, n = 4), abscess (group A, n = 1; group B, n = 1), and thoracic wall burn (group A, n = 4). No significant differences were demonstrated in attenuation increase (P = 0.73), dimensions (P = 0.28, 0.86, 0.06, respectively, comparing D1-D3) and volume (P = 0.17). At histopathology, ablation zones were similar, with septal necrosis, edema, hemorrhage, and peripheral lymphocytic infiltrate. Complete thrombosis of more than 90% of vessels up to 2 mm in diameter was depicted at the periphery of the ablation zone in group A specimens. In group B specimens, complete thrombosis was depicted in 20% of vessels. Feasibility and safety of MW and RF ablation are similar in a lung rabbit model. MW ablation produces a greater damage to peripheral small vessels inducing thrombosis.

  13. Histological characteristics of collagen denaturation and injuries in bipolar radiofrequency-induced colonic anastomoses.

    PubMed

    Zhao, Lingxi; Zhuo, Changhua; Song, Chengli; Li, Xinxiang; Zhou, Yu; Shi, Debing

    2015-03-01

    Bipolar radiofrequency-induced thermo-fusion has been explored as an advanced surgical method for intestinal anastomoses; however, the histological characteristics of collagen denaturation and injuries arising from this process remain unclear. The aim of this study was to investigate the microcosmic changes and tissue damage of fusion regions with various parameters of injury. Ex vivo colons of pigs were fused serosa-serosa on two carrier rings, which were installed on a homemade anastomotic device. Five levels of compressive pressure from 171 to 313 kPa were applied for 5s to fuse the colons under radiofrequency power of 160 W, and then the collagen denaturation of the fused region was examined by transmission electron microscopy. Light microscopy was utilized to observe histological slices that were stained with picrosirius red in order to visualize the tissue injuries under two levels of radiofrequency power (120 vs. 140 W) and operation time (5 vs. 10s). Transmission electron micrographs showed that increased compressive pressure led to thicker denatured collagen fibrils and wider gaps between each collagen fibril. Serosa adhesion regions appeared abundant in collagen. No histological differences were observed when 120 W of power was applied for 5 and 10s. Significant muscle cracking occurred when colons were fused using 140 W for 5s. When the operation time was extended to 10s, 140 W led to tight fusion and less splitting on muscles. These results suggest that higher compressive pressure results in more severe collagen unfolding and also reduces collagen crosslinking in fused colons. Improved radiofrequency power along with operation time could avoid tissue injury upon radiofrequency-induced colonic anastomoses. PMID:25434604

  14. [Stereotactic Radiofrequency Ablation (SRFA) of intrahepatic cholangiocellular carcinomas: a minimal invasive alternative to liver resection].

    PubMed

    Bale, Reto; Schullian, Peter; Haidu, Marion; Widmann, Gerlig

    2013-03-01

    Up to now resection and liver transplantation are concerned as the only curative treatment options for intrahepatic cholangiocellular carcinomas (ICCs). For patients with inoperable ICCs systemic chemotherapy and various locoregional therapies including transarterial (chemo)embolization (TACE), selective internal radiation therapy (SIRT), radiofrequency ablation (RFA) and microwave ablation (MWA) are applied. Stereotactic RFA (SRFA) allows for precise 3D planning and positioning of multiple RF electrodes. Due to overlapping necroses tumors > 5 cm can be completely ablated in one session. 17 inoperable consecutive patients with 52 ICCs were treated with stereotactic RFA (SRFA). A median overall survival of 60 months was achieved. The two largest tumors with diameters > 10 cm were completely ablated. These SRFA data of irresectable ICCs are superior to the published data on resection. SRFA is a minimal invasive alternative treatment to resection and may be considered as the first-line local treatment of patients with ICCs in selected patients. PMID:23392811

  15. Radiofrequency ablation of porcine liver in vivo: effects of blood flow and treatment time on lesion size.

    PubMed Central

    Patterson, E J; Scudamore, C H; Owen, D A; Nagy, A G; Buczkowski, A K

    1998-01-01

    OBJECTIVE: To determine, in vivo, the effect of radiofrequency ablation (RFA) treatment time and tissue blood flow on the size and shape of the resulting necrotic lesion in porcine liver. SUMMARY BACKGROUND DATA: Radiofrequency ablation is an electrosurgical technique that uses a high frequency alternating current to heat tissues to the point of desiccation (thermal coagulation). Radiofrequency ablation is well established as the treatment of choice for many symptomatic cardiac arrhythmias because of its ability to create localized necrotic lesions in the cardiac conducting system. Until recently, a major limitation of RFA was the small lesion size created by this technique. Development of bipolar and multiple-electrode RFA probes has enabled the creation of larger lesions and therefore has expanded the potential clinical applications of RFA, which includes the treatment of liver tumors. A basic understanding of factors that influence RFA lesion size in vivo is critical to the success of this treatment modality. The optimal RFA technique, which maximizes liver lesion size, has yet to be determined. Theoretically, lesion size varies directly with time of application of the RF current, and inversely with blood flow, but these relationships have not been previously studied in the liver. METHODS: Six animals underwent hepatic RFA (460 kHz), for 5, 7.5, 10, 12.5, 15, and 20 minutes. Identical, predetermined anatomic areas of the liver were ablated in each animal. Two additional animals underwent 12 RFA treatments -- 6 with vascular inflow occlusion (Pringle maneuver) and 6 with uninterrupted hepatic blood flow. Animals were euthanized and the livers were removed for gross pathologic examination. All lesions were measured in three dimensions and photographed. Tissues were examined by routine histology and by histochemistry to determine viability. RESULTS: Increasing duration of RFA application from 5 through 20 minutes did not create lesions of larger diameter, but this

  16. Saline Infusion Markedly Reduces Impedance and Improves Efficacy of Pulmonary Radiofrequency Ablation

    SciTech Connect

    Gananadha, Sivakumar Morris, David Lawson

    2004-08-15

    Radiofrequency ablation (RFA) is a relatively new technique that has been investigated for the treatment of lung tumors. We evaluated for the first time the in vivo use of saline infusion during radiofrequency ablation of sheep lung. We performed RFA on 5 sheep using open and closed chest RFA and the RITA starburst XL and Xli probes using saline infusion with the Xli probe. The impedance and volume of ablation were compared. A total of 16 ablations were produced, 5 percutaneously and 11 open. The impedance during percutaneous and open RFA without saline infusion was 110 {+-} 16.2 and 183.3 {+-} 105.8 O, respectively. With the saline infusion the impedance was 71.3 {+-} 22O and 103.6 {+-} 37.5O. The effect of this was a significantly larger volume of ablation using the saline infusion during percutaneous RFA (90.6 {+-} 23 cm{sup 3} vs 10.47 {+-} 2.9 cm{sup 3}, p = 0.01) and open RFA (107.8 {+-} 25.8 cm{sup 3} vs 24.9 {+-} 19.3 cm{sup 3}, p = 0.0002). Saline infusion during RFA is associated with lower impedance, higher power delivery and larger lesion size.

  17. Percutaneous Radiofrequency Ablation of a Small Renal Mass Complicated by Appendiceal Perforation

    SciTech Connect

    Boone, Judith; Bex, Axel; Prevoo, Warner

    2012-06-15

    Percutaneous radiofrequency ablation (RFA) has gained wide acceptance as nephron-sparing therapy for small renal masses in select patients. Generally, it is a safe procedure with minor morbidity and acceptable short-term oncologic outcome. However, as a result of the close proximity of vital structures, such as the bowel, ureter, and large vessels, to the ablative field, complications regarding these structures may occur. This is the first article describing appendiceal perforation as a complication of computed tomography-guided RFA despite hydrodissection. When performing this innovative and promising procedure one should be aware of the possibility of particular minor and even major complications.

  18. A Modified Epicardial Radiofrequency Ablation for Preoperative Atrial Fibrillation Combined With Isolated Aortic Valve Disease.

    PubMed

    Jiang, Zhaolei; Ma, Nan; Liu, Hao; Tang, Min; Ding, Fangbao; Bao, Chunrong; Mei, Ju

    2016-06-01

    Isolated aortic valve diseases can lead to atrial fibrillation (AF) by causing left atrium pressure overload and enlargement. At present, most patients with preoperative AF and isolated aortic valve disease have undergone a Cox-maze IV procedure through a left atriotomy under cardiopulmonary bypass with aortic cross-clamping. Here, we describe a novel modified epicardial radiofrequency ablation procedure performed on a beating heart without aortic cross-clamping or opening the left atrium. This technique has proved to be safe and feasible, with good clinical outcomes. It may be useful in selecting the best ablation approaches for patients with AF and aortic valve disease. PMID:27211963

  19. Semi-spherical Radiofrequency Bipolar Device - A New Technique for Liver Resection: Experimental In Vivo Study on the Porcine Model.

    PubMed

    Vavra, P; Penhaker, M; Jurcikova, J; Skrobankova, M; Crha, M; Ostruszka, P; Ihnat, P; Grepl, J; Delongova, P; Dvorackova, J; Prochazka, V; Salounova, D; Skoric, M; Rauser, P; Habib, N; Zonca, P

    2015-10-01

    The incidence of colorectal carcinoma is still growing in the Czech Republic and also all around the world. With success of oncological treatment is also growing a number of potential patients with liver metastases, who can profit from surgical therapy. The aim of this study was to confirm on porcine models that this method by using new surgical device is effective and safe for patients who have to undergo liver resection. The primary hypothesis of the study was to evaluate whether this new device is able to consistently produce homogeneous and predictable areas of coagulation necrosis without the Pringle maneuver of vascular inflow occlusion. The secondary hypothesis of the study was to compare the standard linear radiofrequency device and a new semi-spherical bipolar device for liver ablation and resection in a hepatic porcine model. Twelve pigs were randomly divided into two groups. Each pig underwent liver resection from both liver lobes in the marginal, thinner part of liver parenchyma. The pigs in first group were operated with standard using device and in the second group we used new developed semi-spherical device. We followed blood count in 0(th), 14(th) and 30(th) day from operation. 14(th) day from resection pigs underwent diagnostic laparoscopy to evaluate of their state, and 30(th) day after operation were all pigs euthanized and subjected to histopathological examination. Histopathological evaluation of thermal changes at the resection margin showed strong thermal alteration in both groups. Statistical analysis of collected dates did not prove any significant (p < 0.05) differences between standard using device and our new surgical tool. We proved safety of new designed semi-spherical surgical. This device can offer the possibility of shortening the ablation time and operating time, which is benefit for patients undergoing the liver resection. PMID:24945372

  20. Intraductal radiofrequency ablation of tumour ingrowth into an uncovered metal stent used for inoperable cholangiocarcinoma.

    PubMed

    Lui, K L; Li, K K

    2013-12-01

    A 91-year-old woman diagnosed to have an inoperable cholangiocarcinoma had an uncovered metal stent inserted for palliative drainage. About 1.5 years later, tumour ingrowth into the metal stent caused cholangitis. Intraductal radiofrequency ablation was applied to create local coagulative tumour necrosis and the necrotic tissue was removed via a balloon catheter. A plastic stent was inserted to empirically treat any ensuing potential bile duct injury. The patient was discharged without complication with good palliative drainage. Intraductal radiofrequency ablation is a new technique for the treatment of metal stent occlusion due to tumour ingrowths. This is the first case report of this relatively safe and feasible new technique for the treatment of tumour ingrowth into a metal stent used as palliation for malignant biliary obstruction. PMID:24310661

  1. Chemoembolisation combined with percutaneous radiofrequency ablation in the treatment of primary angiosarcoma of the liver

    PubMed Central

    Nunes, Thiago Franchi; Barbosa, Fabio Colagrossi Paes; Miiji, Luciana Nakao Odashiro; de Souza, Luiz Gustavo Orlandi

    2013-01-01

    Angiosarcoma of the liver is a rare disease; however, it ranks as the third most common primary liver malignancy. Diagnosis is difficult and prognosis is very poor. After the onset of clinical symptoms, the disease often progresses rapidly, decreasing the chances of curative treatment. We report the case of an 83-year-old male patient who presented with postprandial fullness. Upper abdominal ultrasound showed a hypervascular mass in segment 6 of the liver. The results of anatomopathological examination and immunohistochemistry were compatible with the diagnosis of primary angiosarcoma of the liver. Patient refused surgery (haepatectomy), and treatment was then initiated with transarterial chemoembolisation, followed by percutaneous radiofrequency ablation. The patient is currently cured based on clinical and radiological evidence. This case report is the first in the literature to describe the combined use of transarterial chemoembolisation with percutaneous radiofrequency ablation in the treatment of primary angiosarcoma of the liver. PMID:23704445

  2. Efficacy comparison between cryoablation and radiofrequency ablation for patients with cavotricuspid valve isthmus dependent atrial flutter: a meta-analysis.

    PubMed

    Chen, Yi-He; Lin, Hui; Xie, Cheng-Long; Zhang, Xiao-Ting; Li, Yi-Gang

    2015-01-01

    We perform this meta-analysis to compare the efficacy and safety of cryoablation versus radiofrequency ablation for patients with cavotricuspid valve isthmus dependent atrial flutter. By searching EMBASE, MEDLINE, PubMed and Cochrane electronic databases from March 1986 to September 2014, 7 randomized clinical trials were included. Acute (risk ratio[RR]: 0.93; P = 0.14) and long-term (RR: 0.94; P = 0.08) success rate were slightly lower in cryoablation group than in radiofrequency ablation group, but the difference was not statistically significant. Additionally, the fluoroscopy time was nonsignificantly reduced (weighted mean difference[WMD]: -2.83; P = 0.29), whereas procedure time was significantly longer (WMD: 25.95; P = 0.01) in cryoablation group compared with radiofrequency ablation group. Furthermore, Pain perception during the catheter ablation was substantially less in cryoablation group than in radiofrequency ablation group (standardized mean difference[SMD]: -2.36; P < 0.00001). Thus, our meta-analysis demonstrated that cryoablation and radiofrequency ablation produce comparable acute and long-term success rate for patients with cavotricuspid valve isthmus dependent atrial flutter. Meanwhile, cryoablation ablation tends to reduce the fluoroscopy time and significantly reduce pain perception in cost of significantly prolonged procedure time. PMID:26039980

  3. Efficacy comparison between cryoablation and radiofrequency ablation for patients with cavotricuspid valve isthmus dependent atrial flutter: a meta-analysis

    NASA Astrophysics Data System (ADS)

    Chen, Yi-He; Lin, Hui; Xie, Cheng-Long; Zhang, Xiao-Ting; Li, Yi-Gang

    2015-06-01

    We perform this meta-analysis to compare the efficacy and safety of cryoablation versus radiofrequency ablation for patients with cavotricuspid valve isthmus dependent atrial flutter. By searching EMBASE, MEDLINE, PubMed and Cochrane electronic databases from March 1986 to September 2014, 7 randomized clinical trials were included. Acute (risk ratio[RR]: 0.93; P = 0.14) and long-term (RR: 0.94; P = 0.08) success rate were slightly lower in cryoablation group than in radiofrequency ablation group, but the difference was not statistically significant. Additionally, the fluoroscopy time was nonsignificantly reduced (weighted mean difference[WMD]: -2.83 P = 0.29), whereas procedure time was significantly longer (WMD: 25.95; P = 0.01) in cryoablation group compared with radiofrequency ablation group. Furthermore, Pain perception during the catheter ablation was substantially less in cryoabaltion group than in radiofrequency ablation group (standardized mean difference[SMD]: -2.36 P < 0.00001). Thus, our meta-analysis demonstrated that cryoablation and radiofrequency ablation produce comparable acute and long-term success rate for patients with cavotricuspid valve isthmus dependent atrial flutter. Meanwhile, cryoablation ablation tends to reduce the fluoroscopy time and significantly reduce pain perception in cost of significantly prolonged procedure time.

  4. Transhepatic CT-Guided Radiofrequency Ablation of Adrenal Metastases from Hepatocellular Carcinoma

    SciTech Connect

    Kuehl, Hilmar Stattaus, Joerg; Forsting, Michael; Antoch, Gerald

    2008-11-15

    The prognosis of patients with adrenal metastases from hepatocellular carcinoma (HCC) has been poor, and aggressive treatment of these tumors is mandatory to improve patients' survival. Since adrenalectomy may be difficult to perform after previous surgery of the right liver lobe, other approaches are required to treat the adrenal mass. This report aims at demonstrating the feasibility of CT-guided transhepatic radiofrequency ablation of right adrenal HCC metastases pretreated with chemoembolization in patients unable to undergo surgical resection.

  5. Radiofrequency Ablation of Lung Tumours with the Patient Under Thoracic Epidural Anaesthesia

    SciTech Connect

    Pouliquen, Cassiopee; Kabbani, Youssef Saignac, Pierre; Gekiere, Jean-Pierre; Palussiere, Jean

    2011-02-15

    Radiofrequency ablation of lung tumours is a curative technique that is newly considered being offered to nonsurgical patients. It is of major interest because it enables local destruction of the tumour without surgery and spares healthy parenchyma. However, some patients have previous serious respiratory failure, thus ruling out mechanical ventilation. To operate with the patient under thoracic epidural is an answer to this problem. Our experience shows that the procedure is able to be performed completely without converting to general anaesthesia.

  6. Radiofrequency catheter ablation in patients with Wolff-Parkinson-White syndrome.

    PubMed Central

    Thakur, R K; Klein, G J; Yee, R

    1994-01-01

    OBJECTIVE: To report on the experience with radiofrequency catheter ablation of accessory atrioventricular pathways in patients with Wolff-Parkinson-White syndrome in terms of the duration of fluoroscopy exposure to the patient and the operator and the effect of accessory-pathway location and operator experience on the success rate. DESIGN: Retrospective review. SETTING: Tertiary care university hospital. PATIENTS: Two hundred consecutive patients with Wolff-Parkinson-White syndrome who underwent radiofrequency catheter ablation between September 1990 and June 1992. INTERVENTIONS: Electrophysiologic study and radiofrequency catheter ablation. MAIN OUTCOME MEASURES: Success rate, duration of fluoroscopy, complications and long-term follow-up. RESULTS: Of the 224 accessory pathways in the 200 patients 135 were left free wall, 47 posteroseptal, 32 right free wall and 10 anteroseptal. The overall success rate increased from 53% in the first 3 months of the study period to 96% in the last 3 months. The success rate depended on the location of the accessory pathway. The duration of fluoroscopic exposure decreased from 50 (standard deviation [SD] 21) minutes in the first 3 months to 40 (SD 15) minutes in the last 3 months (p < 0.05). Complications occurred in 3.5% of the patients; they included hemopericardium, cerebral embolism, perforation of the right atrial wall, air embolism in a coronary artery and hematoma at the arterial perforation site. None of the complications resulted in death. CONCLUSIONS: With experience, radiofrequency catheter ablation of accessory pathways can have an overall success rate of more than 95% and a complication rate of less than 4%. Such rates make this procedure suitable for first-line therapy for patients with Wolff-Parkinson-White syndrome. Images Fig. 1 PMID:8087753

  7. High versus moderate energy use of bipolar fractional radiofrequency in the treatment of acne scars: a split-face double-blinded randomized control trial pilot study.

    PubMed

    Phothong, Weeranut; Wanitphakdeedecha, Rungsima; Sathaworawong, Angkana; Manuskiatti, Woraphong

    2016-02-01

    Bipolar fractional radiofrequency (FRF) device was firstly FDA-approved for treating atrophic acne scar in 2008 through the process of dermal coagulation and minimal epidermal ablation. The average energy at 60 mJ/pin was widely used to treat atrophic acne scars. However, the higher energy was delivered, the deeper ablation and coagulation were found. At present, the new generation of a device with bipolar FRF technology with electrode-pin tip was developed to maximize ability to deliver energy up to 100 mJ/pin. The objective of the study was to explore and compare the efficacy of utilizing high energy (100 mJ/pin) and moderate energy (60 mJ/pin) of bipolar fractional radiofrequency in treatment of atrophic acne scar in Asians. This is a split-face, double-blinded, randomized control trial, pilot study by using parallel group design technique. Thirty healthy subjects with Fitzpatrick skin phototype III-IV diagnosed as atrophic acne scares were enrolled. All subjects received four monthly sessions of bipolar FRF treatment. Left and right facial sides of individual patients were randomly assigned for different energy (high energy at 100 mJ/pin versus moderate energy at 60 mJ/pin). Acne scars improvement was blinded graded by dermatologist using global acne scarring score (GASS) which was subjectively evaluated at baseline, 1-, 3-, and 6-month follow-up. Objective scar analysis was also done using UVA-light video camera to measure scar volume, skin smoothness, and wrinkle at baseline, 3-, and 6-month follow-up after the last treatment. Side effects including pain, erythema, swelling, and crusting were also recorded. Thirty subjects completed the study with full 4-treatment course. The mean GASS of high energy side and moderate energy side was significantly reduced at 1-, 3-, and 6-month follow-up visits. At 1 month follow-visit, high energy side demonstrated significant improvement compared with moderate energy side (p = 0.03). Postinflammatory hyperpigmentation

  8. Should radiofrequency current ablation be performed in asymptomatic patients with the Wolff-Parkinson-White syndrome?

    PubMed

    Steinbeck, G

    1993-03-01

    The exiting new method of ablation of accessory pathways using radiofrequency current applied by catheters will dramatically change our therapeutic decisions in these patients in the near future. This brief survey reviews the existing literature about the risk of the disease as well as of the procedure of catheter ablation. From these data, the risk of sudden death appears to be extremely low in asymptomatic Wolff-Parkinson-White (WPW) individuals. Side effects of catheter ablation may result from the invasive procedure as well as from radiation exposure (the latter to the patient as well as to operating physicians). While the complication rate in experienced centers is extremely low, a multicenter registry of the success and complication rate is urgently needed in view of the many centers starting with catheter ablation. Based on a subjective benefit-to-risk analysis, asymptomatic WPW individuals should be offered catheter ablation only under special circumstances (high risk profession, athletes, family history of sudden death). On the other hand, catheter ablation need not be and should not be considered generally in asymptomatic individuals with WPW pattern. Finally, this author cannot imagine that the energy, time, and money spent for mass screening and eventual catheter ablation of asymptomatic WPW individuals with its attending risks can be outweighed by the potential benefits for these asymptomatic individuals. PMID:7681970

  9. Prevention of immediate recurrence of atrial fibrillation with low-dose landiolol after radiofrequency catheter ablation

    PubMed Central

    Ishigaki, Daisuke; Arimoto, Takanori; Iwayama, Tadateru; Hashimoto, Naoaki; Kutsuzawa, Daisuke; Kumagai, Yu; Nishiyama, Satoshi; Takahashi, Hiroki; Shishido, Tetsuro; Miyamoto, Takuya; Watanabe, Tetsu; Kubota, Isao

    2015-01-01

    Background Immediate recurrence of atrial fibrillation (AF) after radiofrequency (RF) catheter ablation is commonly observed within 3 d after the procedure. The mechanism and pharmacological management of immediate AF recurrence remain unclear. Methods A total of 50 consecutive patients with paroxysmal AF were randomized to receive either low-dose landiolol (landiolol group) or a placebo (placebo group). In the landiolol group, intravenous landiolol (0.5 μg kg−1 min−1) was administered for 3 d after AF ablation. Results No serious adverse event associated with RF catheter ablation or landiolol administration was observed. The prevalence of immediate AF recurrence (≤3 d after RF catheter ablation) was significantly lower in the landiolol group than in the placebo group (16% vs. 48%, p=0.015). Although the postprocedural change in heart rate was significantly lower in the landiolol group compared to that in the placebo group, the changes in blood pressure and body temperature were not different between the two groups. Multiple logistic regression analysis revealed that landiolol treatment was the only independent predictor of immediate AF recurrence after ablation (odds ratio: 0.180; 95% confidence interval: 0.044–0.729; p=0.016). Conclusions Prophylactic administration of low-dose landiolol after AF ablation may be effective and safe for preventing immediate AF recurrence within 3 d after AF ablation. PMID:26550083

  10. Radiofrequency catheter ablation of Mahaim tachycardia by targeting Mahaim potentials at the tricuspid annulus.

    PubMed Central

    Heald, S. C.; Davies, D. W.; Ward, D. E.; Garratt, C. J.; Rowland, E.

    1995-01-01

    BACKGROUND--Reentrant tachycardias associated with Mahaim pathways are rare but potentially troublesome. Various electrophysiological substrates have been postulated and catheter ablation at several sites has been described. OBJECTIVE--To assess the efficacy and feasibility of targeting discrete Mahaim potentials recorded on the tricuspid annulus for the delivery of radiofrequency energy in the treatment of Mahaim tachycardia. PATIENTS--21 patients out of a consecutive series of 579 patients referred to one of three tertiary centres for catheter ablation of accessory pathways causing tachycardia. All had symptoms and presented with tachycardia of left bundle branch block configuration or had this induced at electrophysiological study. In all cases, the tachycardia was antidromic with anterograde conduction over a Mahaim pathway. RESULTS--6 patients had additional tachycardia substrates (4 had accessory atrioventricular connections and 2 had dual atrioventricular nodal pathways and atrioventricular nodal reentry). After ablation of the additional pathways, Mahaim potentials were identified in 16 (76%) associated with early activation of the distal right bundle branch and radiofrequency energy at this site on the tricuspid annulus abolished Mahaim conduction in all 16 cases. In 2 patients there was early ventricular activation at the annulus without a Mahaim potential but radiofrequency energy abolished pre-excitation. In the remaining patients no potential could be found (1 patient), no tachycardia could be induced after ablation of an additional pathway (1 patient), or no Mahaim conduction was evident during the study (1 patient). During follow up (1-29 months (median 9 months)) all but 1 patient remained symptom free without medication. CONCLUSIONS--Additional accessory pathways seem to be common in patients with Mahaim tachycardias. The identification of Mahaim potentials at the tricuspid annulus confirms that most of these pathways are in the right free wall and

  11. The Evolution of Tissue Stiffness at Radiofrequency Ablation Sites During Lesion Formation and in the Peri‐Ablation Period

    PubMed Central

    EYERLY, STEPHANIE A.; VEJDANI‐JAHROMI, MARYAM; DUMONT, DOUGLAS M.; TRAHEY, GREGG E.

    2015-01-01

    Peri‐Ablation Monitoring of RFA Lesion Stiffness Introduction Elastography imaging can provide radiofrequency ablation (RFA) lesion assessment due to tissue stiffening at the ablation site. An important aspect of assessment is the spatial and temporal stability of the region of stiffness increase in the peri‐ablation period. The aim of this study was to use 2 ultrasound‐based elastography techniques, shear wave elasticity imaging (SWEI) and acoustic radiation force impulse (ARFI) imaging, to monitor the evolution of tissue stiffness at ablation sites in the 30 minutes following lesion creation. Methods and Results In 6 canine subjects, SWEI measurements and 2‐D ARFI images were acquired at 6 ventricular endocardial RFA sites before, during, and for 30 minutes postablation. An immediate increase in tissue stiffness was detected during RFA, and the area of the postablation region of stiffness increase (RoSI) as well as the relative stiffness at the RoSI center was stable approximately 2 minutes after ablation. Of note is the observation that relative stiffness in the region adjacent to the RoSI increased slightly during the first 15 minutes, consistent with local fluid displacement or edema. The magnitude of this increase, ∼0.5‐fold from baseline, was significantly less than the magnitude of the stiffness increase directly inside the RoSI, which was greater than 3‐fold from baseline. Conclusions Ultrasound‐based SWEI and ARFI imaging detected an immediate increase in tissue stiffness during RFA, and the stability and magnitude of the stiffness change suggest that consistent elasticity‐based lesion assessment is possible 2 minutes after and for at least 30 minutes following ablation. PMID:25970142

  12. Computed Tomography-Guided Radiofrequency Ablation Following Transcatheter Arterial Embolization in Treatment of Large Hepatic Hemangiomas

    PubMed Central

    Ji, Jiansong; Gao, Jun; Zhao, Lizhen; Tu, Jianfei; Song, Jingjing; Sun, Wenbing

    2016-01-01

    Abstract The aim of the study was to evaluate the feasibility, safety, and efficacy of computed tomography (CT)-guided radiofrequency (RF) ablation combined with transcatheter arterial embolization (TAE) to treat large (≥10 cm) hepatic hemangiomas. We retrospectively reviewed our sequential experience with 15 large hepatic hemangiomas in 15 patients. The mean diameter of the 15 hemangiomas was 13.0 ± 2.2 cm (10.0–16.0 cm). RF ablation combined with TAE treatment was performed successfully in all patients. The mean diameter of the hemangiomas decreased from 13.0 ± 2.2 to 7.1 ± 2.0 cm (P < 0.001) after TAE treatment. Out of 15 hepatic hemangiomas, 14 (93.3%) showed no enhancement on CT or MRI indicating complete ablation after RF treatment. The mean diameter of the ablation zone decreased to 6.1 ± 2.0 cm 1 month after ablation and further decreased to 4.9 ± 1.6 cm 6 months after ablation. There were 6 complications related to the ablation in 4 patients. According to the Dindo–Clavien classification, all the complications were minor (Grade I). RF ablation combined with TAE is a safe and effective treatment for large hepatic hemangiomas. TAE can improve the disruption of lesion blood supply and reduce lesion size to facilitate subsequent RF ablation and reduce the risk of ablation-related complications. PMID:27082617

  13. Finite Element Analysis of Hepatic Radiofrequency Ablation Probes using Temperature-Dependent Electrical Conductivity

    PubMed Central

    Chang, Isaac

    2003-01-01

    Background Few finite element models (FEM) have been developed to describe the electric field, specific absorption rate (SAR), and the temperature distribution surrounding hepatic radiofrequency ablation probes. To date, a coupled finite element model that accounts for the temperature-dependent electrical conductivity changes has not been developed for ablation type devices. While it is widely acknowledged that accounting for temperature dependent phenomena may affect the outcome of these models, the effect has not been assessed. Methods The results of four finite element models are compared: constant electrical conductivity without tissue perfusion, temperature-dependent conductivity without tissue perfusion, constant electrical conductivity with tissue perfusion, and temperature-dependent conductivity with tissue perfusion. Results The data demonstrate that significant errors are generated when constant electrical conductivity is assumed in coupled electrical-heat transfer problems that operate at high temperatures. These errors appear to be closely related to the temperature at which the ablation device operates and not to the amount of power applied by the device or the state of tissue perfusion. Conclusion Accounting for temperature-dependent phenomena may be critically important in the safe operation of radiofrequency ablation device that operate near 100°C. PMID:12780939

  14. CT-Guided Radiofrequency Ablation in Patients with Hepatic Metastases from Breast Cancer

    SciTech Connect

    Jakobs, Tobias F. Hoffmann, Ralf-Thorsten; Schrader, Angelika; Stemmler, Hans Joachim; Trumm, Christoph; Lubienski, Andreas; Murthy, Ravi; Helmberger, Thomas K.; Reiser, Maximilian F.

    2009-01-15

    The purpose of this study was to evaluate technical success, technique effectiveness, and survival following radiofrequency ablation for breast cancer liver metastases and to determine prognostic factors. Forty-three patients with 111 breast cancer liver metastases underwent CT-guided percutaneous radiofrequency (RF) ablation. Technical success and technique effectiveness was evaluated by performing serial CT scans. We assessed the prognostic value of hormone receptor status, overexpression of human epidermal growth factor receptor 2 (HER2), and presence of extrahepatic tumor spread. Survival rates were calculated using the Kaplan-Meier method. Technical success was achieved in 107 metastases (96%). Primary technique effectiveness was 96%. During follow-up local tumor progression was observed in 15 metastases, representing a secondary technique effectiveness of 86.5%. The overall time to progression to the liver was 10.5 months. The estimated overall median survival was 58.6 months. There was no significant difference in terms of survival probability with respect to hormone receptor status, HER2 overexpression, and presence of isolated bone metastases. Survival was significantly lower among patients with extrahepatic disease, with the exception of skeletal metastases. We conclude that CT-guided RF ablation of liver metastases from breast cancer can be performed with a high degree of technical success and technique effectiveness, providing promising survival rates in patients with no visceral extrahepatic disease. Solitary bone metastases did not negatively affect survival probability after RF ablation.

  15. Influence of Radiofrequency Ablation of Lung Cancer on Pulmonary Function

    SciTech Connect

    Tada, Akihiro Hiraki, Takao; Iguchi, Toshihiro; Gobara, Hideo; Mimura, Hidefumi; Toyooka, Shinichi; Kiura, Katsuyuki; Tsuda, Toshihide; Mitsuhashi, Toshiharu; Kanazawa, Susumu

    2012-08-15

    Purpose: The purpose of this study was to evaluate altered pulmonary function retrospectively after RFA. Methods: This retrospective study comprised 41 ablation sessions for 39 patients (22 men and 17 women; mean age, 64.8 years). Vital capacity (VC) and forced expiratory volume in 1 s (FEV{sub 1}) at 1 and 3 months after RFA were compared with the baseline (i.e., values before RFA). To evaluate the factors that influenced impaired pulmonary function, univariate analysis was performed by using multiple variables. If two or more variables were indicated as statistically significant by univariate analysis, these variables were subjected to multivariate analysis to identify independent factors. Results: The mean VC and FEV{sub 1} before RFA and 1 and 3 months after RFA were 3.04 and 2.24 l, 2.79 and 2.11 l, and 2.85 and 2.13 l, respectively. The values at 1 and 3 months were significantly lower than the baseline. Severe pleuritis after RFA was identified as the independent factor influencing impaired VC at 1 month (P = 0.003). For impaired FEV{sub 1} at 1 month, only severe pleuritis (P = 0.01) was statistically significant by univariate analysis. At 3 months, severe pleuritis (VC, P = 0.019; FEV{sub 1}, P = 0.003) and an ablated parenchymal volume {>=}20 cm{sup 3} (VC, P = 0.047; FEV{sub 1}, P = 0.038) were independent factors for impaired VC and FEV{sub 1}. Conclusions: Pulmonary function decreased after RFA. RFA-induced severe pleuritis and ablation of a large volume of marginal parenchyma were associated with impaired pulmonary function.

  16. Technologies for Guidance of Radiofrequency Ablation in the Multimodality Interventional Suite of the Future

    PubMed Central

    Wood, Bradford J.; Locklin, Julia K.; Viswanathan, Anand; Kruecker, Jochen; Haemmerich, Dieter; Cebral, Juan; Sofer, Ariela; Cheng, Ruida; McCreedy, Evan; Cleary, Kevin; McAuliffe, Matthew J.; Glossop, Neil; Yanof, Jeff

    2008-01-01

    Several new image-guidance tools and devices are being prototyped, investigated, and compared. These tools are introduced and include prototype software for image registration and fusion, thermal modeling, electromagnetic tracking, semiautomated robotic needle guidance, and multimodality imaging. The integration of treatment planning with computed tomography robot systems or electromagnetic needle-tip tracking allows for seamless, iterative, “see-and-treat,” patient-specific tumor ablation. Such automation, navigation, and visualization tools could eventually optimize radiofrequency ablation and other needle-based ablation procedures and decrease variability among operators, thus facilitating the translation of novel image-guided therapies. Much of this new technology is in use or will be available to the interventional radiologist in the near future, and this brief introduction will hopefully encourage research in this emerging area. PMID:17296700

  17. Technologies for guidance of radiofrequency ablation in the multimodality interventional suite of the future.

    PubMed

    Wood, Bradford J; Locklin, Julia K; Viswanathan, Anand; Kruecker, Jochen; Haemmerich, Dieter; Cebral, Juan; Sofer, Ariela; Cheng, Ruida; McCreedy, Evan; Cleary, Kevin; McAuliffe, Matthew J; Glossop, Neil; Yanof, Jeff

    2007-01-01

    Several new image-guidance tools and devices are being prototyped, investigated, and compared. These tools are introduced and include prototype software for image registration and fusion, thermal modeling, electromagnetic tracking, semiautomated robotic needle guidance, and multimodality imaging. The integration of treatment planning with computed tomography robot systems or electromagnetic needle-tip tracking allows for seamless, iterative, "see-and-treat," patient-specific tumor ablation. Such automation, navigation, and visualization tools could eventually optimize radiofrequency ablation and other needle-based ablation procedures and decrease variability among operators, thus facilitating the translation of novel image-guided therapies. Much of this new technology is in use or will be available to the interventional radiologist in the near future, and this brief introduction will hopefully encourage research in this emerging area. PMID:17296700

  18. Spontaneous Regression of Multiple Pulmonary Metastases After Radiofrequency Ablation of a Single Metastasis

    SciTech Connect

    Rao, Pramod; Escudier, Bernard; Baere, Thierry de

    2011-04-15

    We report two cases of spontaneous regression of multiple pulmonary metastases occurring after radiofrequency ablation (RFA) of a single lung metastasis. To the best of our knowledge, these are the first such cases reported. These two patients presented with lung metastases progressive despite treatment with interleukin-2, interferon, or sorafenib but were safely ablated with percutaneous RFA under computed tomography guidance. Percutaneous RFA allowed control of the targeted tumors for >1 year. Distant lung metastases presented an objective response despite the fact that they received no targeted local treatment. Local ablative techniques, such as RFA, induce the release of tumor-degradation product, which is probably responsible for an immunologic reaction that is able to produce a response in distant tumors.

  19. Endovenous Radiofrequency Thermal Ablation and Ultrasound-Guided Foam Sclerotherapy in Treatment of Klippel-Trenaunay Syndrome

    PubMed Central

    2014-01-01

    Introduction: Klippel-Trenaunay syndrome is composed of port-wine stain, limb hypertrophy and varicose veins. Methods: The two patients with Klippel-Trenaunay syndrome treated by endovenous radiofrequency thermal ablation and ultrasound-guided foam sclerotherapy of the abnormal veins was conducted. Results: Radiofrequency thermal ablation resulted in successful occlusion of the incompetent anterior accessory great saphenous vein. Moreover, ultrasound-guided foam sclerotherapy showed complete occlusion of the residual veins. At 6 month follow-up, both patients markedly decreased leg symptoms including pain, cramping, limb swelling, and bulging of veins. Conclusion: Radiofrequency thermal ablation combined with foam sclerotherapy is a minimally invasive procedure alternative to the standard invasive surgery and can be the option for saphenous ablation in Klippel-Trenaunay syndrome patients. PMID:24719663

  20. Microwaves create larger ablations than radiofrequency when controlled for power in ex vivo tissue

    PubMed Central

    Andreano, A.; Huang, Yu; Meloni, M. Franca; Lee, Fred T.; Brace, Christopher

    2010-01-01

    Purpose: To compare ablation zones created with equal amounts of 2.45 GHz microwave and 480 kHz radiofrequency (RF) energy in ex vivo liver and lung. Methods: A total of 38 ablations were performed in ex vivo liver and lung for 10 min each. Nineteen RF ablations (nine liver, ten lung) were performed with a 480 kHz system (200 W max, impedance-based pulsing) and cooled electrode while measuring the average RF power applied. Nineteen microwave ablations (nine liver, ten lung) were then created using a cooled triaxial antenna to deliver 2.45 GHz at the same power level as in RF experiments. Ablation zones were then sectioned and measured for minimum, maximum and mean diameters, and circularity. Measurements were compared using t-tests, with P<0.05 indicating statistical significance. Results: Mean diameters of microwave ablations were greater than RF ablations in both liver and lung (4.4±0.3 vs 3.3±0.2 cm in liver; 2.45±0.3 vs 1.6±0.5 cm in lungs; P<0.0005 all comparisons). There was no significant difference in the mean power applied during microwave or RF ablations in either organ (54.44±1.71 W vs 56.4±6.7 W in liver, P>0.05; 40±0.95 W vs 44.9±7.1 W in lung, P>0.05). Conclusions: Using a single cooled applicator, microwave energy at 2.45 GHz produces larger ablations than an equivalent amount of 480 kHz RF energy in normal liver and lung. This was more apparent in lung, likely due to the high baseline impedance which limits RF, but not microwave power delivery. PMID:20632609

  1. New-onset ventricular arrhythmias post radiofrequency catheter ablation for atrial fibrillation.

    PubMed

    Wu, Lingmin; Lu, Yanlai; Yao, Yan; Zheng, Lihui; Chen, Gang; Ding, Ligang; Hou, Bingbo; Qiao, Yu; Sun, Wei; Zhang, Shu

    2016-09-01

    As a new complication, new-onset ventricular arrhythmias (VAs) post atrial fibrillation (AF) ablation have not been well defined. This prospective study aimed to describe the details of new-onset VAs post AF ablation in a large study cohort.One thousand fifty-three consecutive patients who underwent the first radiofrequency catheter ablation for AF were enrolled. All patients had no evidence of pre-ablation VAs. New-onset VAs were defined as new-onset ventricular tachycardia (VT) or premature ventricular contractions (PVC) ≥1000/24 h within 1 month post ablation.There were 46 patients (4.4%) who had 62 different new-onset VAs, among whom 42 were PVC alone, and 4 were PVC coexisting with nonsustained VT. Multivariate analysis showed that increased serum leukocyte counts ≥50% post ablation were independently associated with new-onset VAs (OR: 1.9; 95% CI: 1.0-3.5; P = 0.043). The median number of PVC was 3161 (1001-27,407) times/24 h. Outflow tract VAs were recorded in 35 (76.1%) patients. No significant differences were found in origin of VAs (P = 0.187). VAs disappeared without any treatment in 6 patients (13.0%). No VAs-related adverse cardiac event occurred.The study revealed a noticeable prevalence but relatively benign prognosis of new-onset VAs post AF ablation. Increased serum leukocyte counts ≥50% post ablation appeared to be associated with new-onset VAs, implying that inflammatory response caused by ablation might be the mechanism. PMID:27603357

  2. Ultrasound-Guided Percutaneous Radiofrequency Ablation of Liver Tumors: How We Do It Safely and Completely.

    PubMed

    Kim, Jin Woong; Shin, Sang Soo; Heo, Suk Hee; Hong, Jun Hyung; Lim, Hyo Soon; Seon, Hyun Ju; Hur, Young Hoe; Park, Chang Hwan; Jeong, Yong Yeon; Kang, Heoung Keun

    2015-01-01

    Ultrasound-guided percutaneous radiofrequency (RF) ablation has become one of the most promising local cancer therapies for both resectable and nonresectable hepatic tumors. Although RF ablation is a safe and effective technique for the treatment of liver tumors, the outcome of treatment can be closely related to the location and shape of the tumors. There may be difficulties with RF ablation of tumors that are adjacent to large vessels or extrahepatic heat-vulnerable organs and tumors in the caudate lobe, possibly resulting in major complications or treatment failure. Thus, a number of strategies have been developed to overcome these challenges, which include artificial ascites, needle track ablation, fusion imaging guidance, parallel targeting, bypass targeting, etc. Operators need to use the right strategy in the right situation to avoid the possibility of complications and incomplete thermal tissue destruction; with the right strategy, RF ablation can be performed successfully, even for hepatic tumors in high-risk locations. This article offers technical strategies that can be used to effectively perform RF ablation as well as to minimize possible complications related to the procedure with representative cases and schematic illustrations. PMID:26576111

  3. Advances in Radiofrequency Ablation of the Cerebral Cortex in Primates Using the Venous System: Improvements for Treating Epilepsy with Catheter Ablation Technology

    PubMed Central

    Henz, Benhur D.; Friedman, Paul A.; Bruce, Charles J.; Holmes, David R.; Bower, Mark; Madhavan, Malini; DeSimone, Christopher V.; Wahnschaffe, Douglas; Berhow, Steven; Danielsen, Andrew J.; Ladewig, Dorothy J.; Mikell, Susan B.; Johnson, Susan B.; Suddendorf, Scott H.; Kara, Tomas; Worrell, Gregory A.; Asirvatham, Samuel J.

    2015-01-01

    Background Pharmacology frequently fails for the treatment of epilepsy. Although surgical techniques are effective, these procedures are highly invasive. We describe feasibility and efficacy of minimally invasive mapping and ablation for the treatment of epilepsy. Methods Mapping and radiofrequency ablations were performed via the venous system in eleven baboons and three dogs. Results Mapping in deep cerebral areas was obtained in all animals. High-frequency pacing was able to induce seizure activity of local cerebral tissue in 72% of our attempts. Cerebral activity could be seen during mapping. Ablative lesions were deployed at deep brain sites without steam pops or sudden impedance rise. Histologic analysis showed necrosis at the sites of ablation in all primates. Conclusion Navigation through the cerebral venous system to map seizure activity is feasible. Radiofrequency energy can be delivered transvenously or transcortically to successful ablate cortical tissue in this animal model using this innovative approach. PMID:24836846

  4. Partial splenectomy using a laparoscopic bipolar radiofrequency device: A case report

    PubMed Central

    Wang, Wei-Dong; Lin, Jie; Wu, Zhi-Qiang; Liu, Qing-Bo; Ma, Jing; Chen, Xiao-Wu

    2015-01-01

    We report a 51-year-old female patient with a solitary lymphangioma located in the upper splenic pole which was managed successfully with laparoscopic partial splenectomy. Surgery lasted 170 min and did not require blood transfusions. The patient recovered well post-operatively and was asymptomatic at the 3-mo follow-up. She had a normal platelet count and no recurrence on ultrasonography or computed tomography. Laparoscopic partial splenectomy is a safe, minimally invasive technique for the treatment of solitary splenic lymphangiomas in the splenic pole. We performed the procedure using the HabibTM 4X device. This laparoscopic bipolar radiofrequency device ensured a “bloodless” splenic parenchymal resection. PMID:25805954

  5. Determination of lesion size by ultrasound during radiofrequency catheter ablation.

    PubMed

    Awad, S; Eick, O

    2003-01-01

    The catheter tip temperature that is used to control the radiofrequency generator output poorly correlates to lesion size. We, therefore, evaluated lesions created in vitro using a B-mode ultrasound imaging device as a potential means to assess lesion generation during RF applications non-invasively. Porcine ventricular tissue was immersed in saline solution at 37 degrees C. The catheter was fixed in a holder and positioned in a parallel orientation to the tissue with an array transducer (7.5 MHz) app. 3 cm above the tissue. Lesions were produced either in a temperature controlled mode with a 4-mm tip catheter with different target temperatures (50, 60, 70 and 80 degrees C, 80 W maximum output) or in a power controlled mode (25, 50 and 75 W, 20 ml/min irrigation flow) using an irrigated tip catheter. Different contact forces (0.5 N, 1.0 N) were tested, and RF was delivered for 60 s. A total of 138 lesions was produced. Out of these, 128 could be identified on the ultrasound image. The lesion depth and volume was on average 4.1 +/- 1.6 mm and 52 +/- 53 mm3 as determined by ultrasound and 3.9 +/- 1.7 mm and 52 +/- 55 mm3 as measured thereafter, respectively. A linear correlation between the lesion size determined by ultrasound and that measured thereafter was demonstrated with a correlation coefficient of r = 0.87 for lesion depth and r = 0.93 for lesion volume. We conclude that lesions can be assessed by B-mode ultrasound imaging. PMID:12910859

  6. Optimization of Direct Current-Enhanced Radiofrequency Ablation: An Ex Vivo Study

    SciTech Connect

    Tanaka, Toshihiro Isfort, Peter; Bruners, Philipp; Penzkofer, Tobias; Kichikawa, Kimihiko; Schmitz-Rode, Thomas; Mahnken, Andreas H.

    2010-10-15

    The purpose of this study was to investigate the optimal setting for radiofrequency (RF) ablation combined with direct electrical current (DC) ablation in ex vivo bovine liver. An electrical circuit combining a commercially available RF ablation system with DC was developed. The negative electrode of a rectifier that provides DC was connected to a 3-cm multitined expandable RF probe. A 100-mH inductor was used to prevent electrical leakage from the RF generator. DC was applied for 15 min and followed by RF ablation in freshly excised bovine livers. Electric current was measured by an ammeter. Coagulation volume, ablation duration, and mean amperage were assessed for various DC voltages (no DC, 2.2, 4.5, and 9.0 V) and different RF ablation protocols (stepwise increase from 40 to 80 W, 40 W fixed, and 80 W fixed). Results were compared using Kruskal-Wallis and Mann-Whitney U test. Applying DC with 4.5 or 9.0 V, in combination with 40 W fixed or a stepwise increase of RF energy, resulted in significantly increased zone of ablation size compared with 2.2 V or no DC (P = 0.009). At 4.5 V DC, the stepwise increase of RF energy resulted in the same necrosis size as a 40 W fixed protocol (26.6 {+-} 3.9 vs. 26.5 {+-} 4.0 ml), but ablation duration was significantly decreased (296 {+-} 85 s vs. 423 {+-} 104 s; P = 0.028). Mean amperage was significantly lower at 4.5 V compared with 9.0 V (P = 0.028). Combining a stepwise increase of RF energy with a DC voltage of 4.5 V is most appropriate to increase coagulation volume and to minimize procedure time.

  7. Histological changes in connective tissue of rat tails after bipolar radiofrequency treatment.

    PubMed

    Beltrán-Frutos, E; Bernal-Mañas, C M; Navarro, S; Zuasti, A; Ferrer, C; Canteras, M; Seco-Rovira, V; García-Collado, A J; Pastor, L M

    2012-09-01

    Radiofrequency (RF) has been included in the techniques used in aesthetic surgery/medicine. To date, no studies have performed a histological assessment of changes in the tissue after application of bipolar radiofrequency (BRF) with low energy and frequency. The aim of this study was to examine changes that are produced in connective tissue, principally in the fibroblasts, following BRF treatment. Four groups of rats received a different number of RF sessions (1, 2, 3 and 5). The following parameters were determined: the number of fibroblasts/unit area (FA), the proliferation index (PI), the Heat shock Protein 47 index (HSPI) and the percentage of connective tissue (PC). For statistical analysis, two subgroups (A and B) were made for the variables FA, PI and PC, and another two subgroups (C and D) for the variable HSPI. Significant differences for FA, PI and PC were observed between subgroups A and B, FA and PI having higher values in A, while PC had higher values in B. The HSPI in subgroup C showed significantly higher values than in D. Low energy and frequency BRF led to an increase in the number, proliferation and biosynthetic activity of fibroblasts. The resulting stress suffered by fibroblasts as a result of heat may be associated with the phenomenon of hormesis. PMID:22806911

  8. Theoretical modeling for radiofrequency ablation: state-of-the-art and challenges for the future

    PubMed Central

    Berjano, Enrique J

    2006-01-01

    Radiofrequency ablation is an interventional technique that in recent years has come to be employed in very different medical fields, such as the elimination of cardiac arrhythmias or the destruction of tumors in different locations. In order to investigate and develop new techniques, and also to improve those currently employed, theoretical models and computer simulations are a powerful tool since they provide vital information on the electrical and thermal behavior of ablation rapidly and at low cost. In the future they could even help to plan individual treatment for each patient. This review analyzes the state-of-the-art in theoretical modeling as applied to the study of radiofrequency ablation techniques. Firstly, it describes the most important issues involved in this methodology, including the experimental validation. Secondly, it points out the present limitations, especially those related to the lack of an accurate characterization of the biological tissues. After analyzing the current and future benefits of this technique it finally suggests future lines and trends in the research of this area. PMID:16620380

  9. Temperature-controlled cooled-tip radiofrequency ablation in left ventricular myocardium.

    PubMed

    Watanabe, Ichiro; Nuo, Min; Okumura, Yasuo; Ohkubo, Kimie; Ashino, Sonoko; Kofune, Masayoshi; Kofune, Tatsuya; Nakai, Toshiko; Kasamaki, Yuji; Hirayama, Atsushi

    2010-05-01

    Steam pop and intramural charring have been reported during cooled-tip radiofrequency catheter ablation (RFCA). We studied the feasibility of temperature-controlled cooled-tip RFCA in the canine heart.An internally cooled ablation catheter was inserted into the left ventricle. A custom-made radiofrequency (RF) generator capable of controlling the tip-temperature at the preset level by slow increases in the power was used. Temperature-controlled cooled-tip RF applications were performed at a target temperature of 40 degrees C for 90 seconds. Acute study: Intramyocardial temperature was measured at the ablation site in 10 dogs by inserting a fluoroptic probe. Chronic study: Lesion depth and volume were measured in 5 dogs after 3 weeks of survival. In the acute study, no pop or abrupt impedance rise was observed. Maximum intramyocardial temperature was 72.4 + or - 14.4 degrees C at 2-4 mm above the endocardium. No coagulum formation, craters, or intramural charring were observed. Maximum lesion depth was 6.7 + or - 1.5 mm, and lesion volume was 404 + or - 219 mm3. In the chronic study, maximum lesion depth was 5.9 + or - 1.1 mm, and lesion volume was 281 + or - 210 mm(3).Temperature controlled RFCA is feasible with a cooled-tip catheter and an RF generator that slowly increases the RF power until the preset catheter-tip temperature is reached. PMID:20558910

  10. Safety and feasibility of radiofrequency ablation for treatment of Bosniak IV renal cysts

    PubMed Central

    de Menezes, Marcos Roberto; Viana, Publio Cesar Cavalcante; Yamanari, Tássia Regina; Reis, Leonardo Oliveira; Nahas, William

    2016-01-01

    ABSTRACT Purpose To describe our initial experience with radiofrequency ablation (RFA) of Bosniak IV renal cysts. Materials and Methods From 2010 to 2014, 154 renal tumor cases were treated with percutaneous thermal ablation, of which 10 cases (6.4%) from nine patients were complex renal cysts and were treated with radiofrequency ablation. Results All complex cysts were classified as Bosniak IV (four women and five men; mean age: 63.6 yrs, range: 33–83 years). One patient had a single kidney. Lesion size ranged from 1.5 to 4.1cm (mean: 2.5cm) and biopsy was performed on four cysts immediately before the procedure, all of which were malignant (two clear cell and two papillary carcinoma). Mean volume reduction of complex cysts was 25% (range: 10–40%). No patients required retreatment with RFA and no immediate or late complications were observed. The follow-up of Bosniak IV cysts had a median of 27 months (interquartile range [IQR], 23 to 38) and no recurrence or significant loss of renal function were observed. Conclusions Mid-term follow-up of the cases in our database suggests that image-guided percutaneous RFA can treat Bosniak IV cysts with very low complication rates and satisfactorily maintain renal function. PMID:27286107

  11. Preparation of carbon-coated iron nanofluid and its application in radiofrequency ablation.

    PubMed

    Wu, Qiguang; Zhang, Haiyan; Chen, Minshan; Zhang, Yaojun; Huang, Junting; Xu, Zuowen; Wang, Wenguang

    2015-05-01

    Carbon-coated iron nanoparticles (Fe@C CCINs) were synthesized by carbon arc discharge method and were studied via X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results showed that CCINs have good core-shell structure and are in size of 40-50 nm. Also, carbon-coated iron nanofluid (CCINs-nanofluid) was prepared via two-step method by dispersing as-prepared CCINs and polyvinylpyrrolidone (PVP) into physiological saline. Its dispersion stability and thermal conductivity were detected by gravity sedimentation method and Hotdisk thermal constant analyzer respectively. The results indicated that CCINs-nanofluid possesses good dispersity and stability. Moreover, CCINs-nanofluid showed enhanced thermal conductivity compared with its base fluid physiological saline. The enhancement of thermal conductivity even reaches 41%. Additionally, CCINs-nanofluid injection aided radiofrequency ablation (RFA) was carried out. The relation between tissue temperature and ablation time revealed that by injecting CCINs-nanofluid into pork livers during RFA, target tissue temperatures were less than 100°C. Dissected pork livers showed that there was little or no tissue charring around the ablation probe. Results of ablation area calculation showed that the ablation area of CCINs-nanofluid injection aided RFA was 67% larger than that of saline injection aided RFA, indicating that a larger-volume tumor tissue necrosis at a single session can be achieved by CCINs-nanofluid injection aided RFA. PMID:25171467

  12. A meta-analysis of clinical trials assessing the effect of radiofrequency ablation for breast cancer

    PubMed Central

    Chen, Jiayan; Zhang, Chi; Li, Fei; Xu, Liping; Zhu, Hongcheng; Wang, Shui; Liu, Xiaoan; Zha, Xiaoming; Ding, Qiang; Ling, Lijun; Zhou, Wenbin; Sun, Xinchen

    2016-01-01

    Background Radiofrequency ablation (RFA) is a minimally invasive thermal ablation technique. We conducted a meta-analysis based on eligible studies to assess the efficacy and safety of RFA for treating patients with breast cancer. Methods A literature search was conducted in PubMed, Embase, and Web of Science databases. Eligible studies were clinical trials that assessed RFA in patients with breast cancer. The outcomes included complete ablation rate, recurrence rate, excellent or good cosmetic rates, and complication rate. A random-effects or fixed-effects model was used to pool the estimate, according to the heterogeneity among the included studies. Results Fifteen studies, with a total of 404 patients, were included in this meta-analysis. Pooled results showed that 89% (95% confidence interval: 85%–93%) of patients achieved a complete ablation after RFA treatment and 96% of patients reported a good-to-excellent cosmetic result. Although the pooled result for recurrence rate was 0, several cases of relapse were observed at different follow-up times. No RFA-related complications were recorded, except for skin burn with an incidence of 4% (95% confidence interval: 1%–6%). Conclusion This meta-analysis showed that RFA can be a promising alternative option for treating breast cancer since it produces a higher complete ablation rate with a low complication rate. Further well-designed randomized controlled trials are needed to confirm the efficacy and safety of RFA for breast cancer. PMID:27042126

  13. Novel multi-source phase-controlled radiofrequency technology for non-ablative and micro-ablative treatment of wrinkles, lax skin and acne scars.

    PubMed

    Elman, Monica; Harth, Yoram

    2011-01-01

    The basic properties of lasers and pulsed light sources limit their ability to deliver high energy to the dermis and subcutaneous tissues without excessive damage to the epidermis. Radiofrequency was shown to penetrate deeper than optical light sources independent of skin color. The early RF-based devices used single source bipolar RF, which is safe but limited in use due to the superficial flow of energy between the two bipolar electrodes. Another type of single source RF employs a single electrode (monopolar) in which the RF energy flows from one electrode on the surface of the skin through the entire body to a plate under the body. Although more effective than bipolar, this devices require intense active cooling of the skin and may be associated with considerable pain and other systemic and local safety concerns. Latest generation of RF technology developed by EndyMed Medical Ltd. (Caesarea, Israel) utilizes simultaneously six or more phase controlled RF generators (3DEEP technology). The multiple electrical fields created by the multiple sources "repel" or "attract" each other, leading to the precise 3 dimensional delivery of RF energy to the dermal and sub-dermal targets minimizing the energy flow through the epidermis without the need for active cooling. Confocal microscopy of the skin has shown that 6 treatment sessions of Multisource RF technology improve skin structure features. The skin after treatment had longer and narrower dermal papilla and denser and finer collagen fiber typical to younger skin as compared to pre treatment skin. Ultrasound of the skin showed after 6 treatment sessions reduction of 10 percent in the thickness of the subcutaneous fat layer. Non ablative facial clinical studies showed a significant reduction of wrinkles after treatment further reduced at 3 months follow-up. Body treatment studies showed a circumference reduction of 2.9 cm immediately after 6 treatments, and 2 cm at 12 months after the end of treatment, proving long term

  14. Lung Radiofrequency Ablation: In Vivo Experimental Study with Low-Perfusion-Rate Multitined Electrodes

    SciTech Connect

    Crocetti, Laura Lencioni, Riccardo; Bozzi, Elena; Sbrana, Alberto; Bartolozzi, Carlo

    2008-05-15

    The purpose of this study was to investigate the feasibility and safety of lung radiofrequency (RF) ablation by using low-perfusion-rate, expandable, multitined electrodes in an in vivo animal model. Ten New Zealand White rabbits underwent RF ablation using low-perfusion-rate, expandable, multitined electrodes (Starburst Talon; RITA Medical Systems, Mountain View, CA) and a 200-W RF generator. The electrode was positioned under fluoroscopy guidance and a single percutaneous RF ablation was performed. Saline perfusate was doped with nonionic iodinated contrast agent to render it visible on computed tomography (CT). The pump infused the saline doped with contrast agent into the lateral tines at a rate of 0.1ml/min. The planned ablation was of 3 min, with the hooks deployed to 2 cm at a target temperature of 105{sup o}C. An immediate posttreatment CT scan documented the distribution of the doped saline and the presence of immediate complications. The animals were monitored for delayed complications and sacrificed within 72 h (n = 4), 2 weeks (n = 3), or 4 weeks (n = 3). Assessment of ablation zone and adjacent structures was done at autopsy. Major complications consisted of pneumothorax requiring drainage (n = 2) and skin burn (n = 1). Immediately after the procedure the area of ablation was depicted at CT as a round, well-demarcated area, homogeneously opacified by iodinated contrast medium (mean size, 2.3 {+-} 0.8 cm). The presence of a sharply demarcated area of coagulation necrosis (mean size, 2.1 {+-} 0.4 cm) without severe damage to adjacent structures was confirmed at autopsy. In one case, euthanized at 4 weeks, in whom pneumothorax and pleural effusion were depicted, pleural fibrinous adhesions were demonstrated at autopsy. In conclusion, lung RF ablation performed in an in vivo animal model using low-perfusion-rate, expandable, multitined electrodes is feasible and safe. No severe damage to adjacent structures was demonstrated.

  15. Refractory Jaundice From Intraductal Papillary Mucinous Neoplasm Treated With Cholangioscopy-Guided Radiofrequency Ablation

    PubMed Central

    Brown, Nicholas G.; Camilo, Joel; McCarter, Martin

    2016-01-01

    Intraductal papillary mucinous neoplasms (IPMNs) are epithelial neoplasms treated with surgical resection when appropriate. We present a 79-year-old man with jandice refractory to endoscopic stenting. Biliary radiofrequency ablation (RFA) with cholangioscopy was used as palliation of obstructive jaundice due to a mucin-producing pancreatic IPMN with fistulous biliary communication. Clinical improvement permitted surgery, and he returned to pre-illness status at 17 months. The use of cholangioscopy in the setting of mucinous filling defects can guide over-the-wire RFA for palliation and may be a bridge to surgery. PMID:27144205

  16. Radiofrequency ablation of stellate ganglion in a patient with complex regional pain syndrome

    PubMed Central

    Roy, Chinmoy; Chatterjee, Nilay

    2014-01-01

    Complex regional pain syndrome (CRPS) is characterized by a combination of sensory, motor, vasomotor, pseudomotor dysfunctions and trophic signs. We describe the use of radiofrequency (RF) ablation of Stellate ganglion (SG) under fluoroscopy, for long-term suppression of sympathetic nervous system, in a patient having CRPS-not otherwise specified. Although the effects of thermal RF neurolysis may be partial or temporary, they may promote better conditions toward rehabilitation. The beneficial effect obtained by the RF neurolysis of SG in this particular patient strongly advocates the use of this mode of therapy in patients with CRPS. PMID:25191200

  17. Recent Advances in Radiofrequency Ablation for the Management of Hepatocellular Carcinoma

    PubMed Central

    Himoto, Takashi; Kurokohchi, Kazutaka; Watanabe, Seishiro; Masaki, Tsutomu

    2012-01-01

    Contexts Hepatocellular carcinoma (HCC) is one of the most common malignant diseases in the world. Because less than 20% of patients with HCC are resectable, various types of non-surgical treatment have been developed. Evidence Acquisition At present, radiofrequency ablation (RFA) is accepted as the standard local treatment for patients with HCC because of its superior local control and overall survival compared to other local treatments. Results New devices for RFA and combination treatments of RFA with other procedures have been developed to improve anti-tumoral effects. Conclusions This review mainly focuses on the status of RFA in the management of HCC and recent advances in RFA treatment technology. PMID:23162600

  18. Refractory Jaundice From Intraductal Papillary Mucinous Neoplasm Treated With Cholangioscopy-Guided Radiofrequency Ablation.

    PubMed

    Brown, Nicholas G; Camilo, Joel; McCarter, Martin; Shah, Raj J

    2016-04-01

    Intraductal papillary mucinous neoplasms (IPMNs) are epithelial neoplasms treated with surgical resection when appropriate. We present a 79-year-old man with jandice refractory to endoscopic stenting. Biliary radiofrequency ablation (RFA) with cholangioscopy was used as palliation of obstructive jaundice due to a mucin-producing pancreatic IPMN with fistulous biliary communication. Clinical improvement permitted surgery, and he returned to pre-illness status at 17 months. The use of cholangioscopy in the setting of mucinous filling defects can guide over-the-wire RFA for palliation and may be a bridge to surgery. PMID:27144205

  19. Complete remission of advanced hepatocellular carcinoma by radiofrequency ablation after sorafenib therapy

    PubMed Central

    Park, Jung Gil; Park, Soo Young; Lee, Hye Won

    2015-01-01

    Sorafenib, a potent multikinase inhibitor, lead to a significant improvement in progression free survival and overall survival in patients with advanced hepatocellular carcinoma (HCC). Though sorafenib has proven its efficacy in advanced stage HCC, there are limited reports on the role of sorafenib allowing for curative treatment by down-staging. We herein report a case of advanced HCC with vascular invasion, which showed treatment response by sorafenib therapy as to allow for radiofrequency ablation as curative treatment. The patient was followed-up for 6 mo without recurrence with continued sorafenib therapy. PMID:25741170

  20. Fiber-optic catheter-based polarization-sensitive OCT for radio-frequency ablation monitoring

    PubMed Central

    Fu, Xiaoyong; Wang, Zhao; Wang, Hui; Wang, Yves T; Jenkins, Michael W; Rollins, Andrew M

    2015-01-01

    An all-fiber optic catheter-based polarization-sensitive optical coherence tomography system is demonstrated. A novel multiplexing method was used to illuminate the sample, splitting the light from a 58.5kHz Fourier-domain mode-locked laser such that two different polarization states, alternated in time, are generated by two semiconductor optical amplifiers. A 2.3mm forward-view cone-scanning catheter probe was designed, fabricated, and used to acquire sample scattering intensity and phase retardation images. The system was first verified with a quarter-wave plate and then by obtaining intensity and phase retardation images of high-birefringence plastic, human skin in vivo, and untreated and thermally ablated porcine myocardium ex vivo. The system can potentially in vivo image of the cardiac wall to aid radio-frequency ablation therapy for cardiac arrhythmias. PMID:25166075

  1. Dependence of ultrasound echo decorrelation on local tissue temperature during ex vivo radiofrequency ablation.

    PubMed

    Subramanian, Swetha; Schmidt, Daniel T; Rao, Marepalli B; Mast, T Douglas

    2016-03-21

    This study investigates echo decorrelation imaging, an ultrasound method for thermal ablation monitoring. The effect of tissue temperature on the mapped echo decorrelation parameter was assessed in radiofrequency ablation experiments performed on ex vivo bovine liver tissue. Echo decorrelation maps were compared with corresponding tissue temperatures simulated using the finite element method. For both echo decorrelation imaging and integrated backscatter imaging, the mapped tissue parameters correlated significantly but weakly with local tissue temperature. Receiver operating characteristic (ROC) curves were used to assess the ability of echo decorrelation and integrated backscatter to predict tissue temperature greater than 40, 60, and 80 °C. Significantly higher area under the ROC curve (AUROC) values were obtained for prediction of tissue temperatures greater than 40, 60, and 80 ° C using echo decorrelation imaging (AUROC [Formula: see text] and 0.966) compared to integrated backscatter imaging (AUROC [Formula: see text] and 0.832). PMID:26943026

  2. Dependence of ultrasound echo decorrelation on local tissue temperature during ex vivo radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Subramanian, Swetha; Schmidt, Daniel T.; Rao, Marepalli B.; Mast, T. Douglas

    2016-03-01

    This study investigates echo decorrelation imaging, an ultrasound method for thermal ablation monitoring. The effect of tissue temperature on the mapped echo decorrelation parameter was assessed in radiofrequency ablation experiments performed on ex vivo bovine liver tissue. Echo decorrelation maps were compared with corresponding tissue temperatures simulated using the finite element method. For both echo decorrelation imaging and integrated backscatter imaging, the mapped tissue parameters correlated significantly but weakly with local tissue temperature. Receiver operating characteristic (ROC) curves were used to assess the ability of echo decorrelation and integrated backscatter to predict tissue temperature greater than 40, 60, and 80 °C. Significantly higher area under the ROC curve (AUROC) values were obtained for prediction of tissue temperatures greater than 40, 60, and 80 ° C using echo decorrelation imaging (AUROC =0.871,~0.948 and 0.966) compared to integrated backscatter imaging (AUROC =0.865,~0.877 and 0.832).

  3. Rare complications after lung percutaneous radiofrequency ablation: Incidence, risk factors, prevention and management.

    PubMed

    Alberti, Nicolas; Buy, Xavier; Frulio, Nora; Montaudon, Michel; Canella, Mathieu; Gangi, Afshin; Crombe, Amandine; Palussière, Jean

    2016-06-01

    Among image-guided thermo-ablative techniques, percutaneous radiofrequency ablation (PRFA) is the most widely used technique for the treatment of primary and secondary lung malignancies. Tolerance of PRFA in the lung is excellent. However, relatively little is known about potential rare complications. This article presents both the clinical and imaging features of lung PRFA complications as well as their prevention and management. Complications may be classified in four groups: pleuropulmonary (e.g., bronchopleural or bronchial fistula, delayed abscess or aspergilloma inside post-PRFA cavitations, pulmonary artery pseudo aneurysm, gas embolism and interstitial pneumonia); thoracic wall and vertebral (e.g., rib or vertebral fractures and intercostal artery injury); mediastinal and apical (e.g., neural damage); or diaphragmatic. Most complications can be managed with conservative treatment, percutaneous or endoscopic drainage, or surgical repair. PMID:27161069

  4. Fiber-optic catheter-based polarization-sensitive OCT for radio-frequency ablation monitoring.

    PubMed

    Fu, Xiaoyong; Wang, Zhao; Wang, Hui; Wang, Yves T; Jenkins, Michael W; Rollins, Andrew M

    2014-09-01

    An all-fiber optic catheter-based polarization-sensitive optical coherence tomography system is demonstrated. A novel multiplexing method was used to illuminate the sample, splitting the light from a 58.5 kHz Fourier-domain mode-locked laser such that two different polarization states, alternated in time, are generated by two semiconductor optical amplifiers. A 2.3 mm forward-view cone-scanning catheter probe was designed, fabricated, and used to acquire sample scattering intensity and phase retardation images. The system was first verified with a quarter-wave plate and then by obtaining intensity and phase retardation images of high-birefringence plastic, human skin in vivo, and untreated and thermally ablated porcine myocardium ex vivo. The system can potentially in vivo image of the cardiac wall to aid radio-frequency ablation therapy for cardiac arrhythmias. PMID:25166075

  5. Ultrasound-guided greater occipital nerve blocks and pulsed radiofrequency ablation for diagnosis and treatment of occipital neuralgia.

    PubMed

    Vanderhoek, Matthew David; Hoang, Hieu T; Goff, Brandon

    2013-09-01

    Occipital neuralgia is a condition manifested by chronic occipital headaches and is thought to be caused by irritation or trauma to the greater occipital nerve (GON). Treatment for occipital neuralgia includes medications, nerve blocks, and pulsed radiofrequency ablation (PRFA). Landmark-guided GON blocks are the mainstay in both the diagnosis and treatment of occipital neuralgia. Ultrasound is being utilized more and more in the chronic pain clinic to guide needle advancement when performing procedures; however, there are no reports of ultrasound used to guide a diagnostic block or PRFA of the GON. We report two cases in which ultrasound was used to guide diagnostic greater occipital nerve blocks and greater occipital nerve pulsed radiofrequency ablation for treatment of occipital neuralgia. Two patients with occipital headaches are presented. In Case 1, ultrasound was used to guide diagnostic blocks of the greater occipital nerves. In Case 2, ultrasound was utilized to guide placement of radiofrequency probes for pulsed radiofrequency ablation of the greater occipital nerves. Both patients reported immediate, significant pain relief, with continued pain relief for several months. Further study is needed to examine any difference in outcomes or morbidity between the traditional landmark method versus ultrasound-guided blocks and pulsed radiofrequency ablation of the greater occipital nerves. PMID:24282778

  6. Angled Cool-Tip Electrode for Radiofrequency Ablation of Small Superficial Subcapsular Tumors in the Liver: A Feasibility Study

    PubMed Central

    Kim, Il Jung; Lee, Shin Jae; Shin, Min Woo; Shin, Won Sun; Chung, Yong Eun; Kim, Gyoung Min; Kim, Man Deuk; Won, Jong Yun; Lee, Do Yun; Choi, Jin Sub; Han, Kwang-Hyub

    2016-01-01

    Objective To evaluate the feasibility of angled cool-tip electrode for radiofrequency ablation of small superficial subcapsular liver tumors abutting abdominal wall, in order to traverse normal liver parenchyma, and thereby, obtain favorable configuration of ablation margin. Materials and Methods In this study, we retrospectively analyzed 15 small superficial subcapsular liver tumors abutting abdominal wall in 15 patients, treated with radiofrequency ablation from March 2013 to June 2015 using a cool-tip electrode manually modified to create 25–35° angle at the junction between exposed and insulated segments. The tumors were hepatocellular carcinoma (n = 13) and metastases (n = 2: cholangiocellular carcinoma and rectosigmoid cancer), with maximum diameter of 10–26 mm (mean, 15.68 ± 5.29 mm). Under ultrasonographic guidance, the electrode tip was advanced to the depth of the tumors' epicenter about 1 cm from the margin. The tip was re-directed to penetrate the tumor for radiofrequency ablation. Minimal ablation margin was measured at immediate post-treatment CT. Radiological images and medical records were evaluated for success rate, length of minimal ablation margin and complications. Results Technical success rate of obtaining complete necrosis of the tumors was 100%, with no procedure-related complication. Minimal ablation margin ranged from 3–12 mm (mean, 7.07 ± 2.23 mm). CT/MRI follow-up at 21–1022 days (mean, 519.47 ± 304.51 days) revealed no local recurrence, but distant recurrence in 9 patients. Conclusion Using an angled cool-tip electrode for radiofrequency ablation of small superficial subcapsular tumors abutting abdominal wall may be a feasible technique for obtaining adequate ablation margin and lower complication rate. PMID:27587963

  7. Development of a radiofrequency ablation platform in a clinically relevant murine model of hepatocellular cancer.

    PubMed

    Qi, Xiaoqiang; Li, Guangfu; Liu, Dai; Motamarry, Anjan; Huang, Xiangwei; Wolfe, A Marissa; Helke, Kristi L; Haemmerich, Dieter; Staveley-O'Carroll, Kevin F; Kimchi, Eric T

    2015-01-01

    RFA is used in treatment of patients with hepatocellular cancer (HCC); however, tumor location and size often limit therapeutic efficacy. The absence of a realistic animal model and a radiofrequency ablation (RFA) suitable for small animals presents significant obstacles in developing new strategies. To establish a realistic RFA platform that allows the development of effective RFA-integrated treatment in an orthotopic murine model of HCC, a human cardiac radiofrequency generator was modified for murine use. Parameters were optimized and RFA was then performed in normal murine livers and HCCs. The effects of RFA were monitored by measuring the ablation zone and transaminases. The survival of tumor-bearing mice with and without RFA was monitored, ablated normal liver and HCCs were evaluated macroscopically and histologically. We demonstrated that tissue-mimicking media was able to optimize RFA parameters. Utilizing this information we performed RFA in normal and HCC-bearing mice. RFA was applied to hepatic parenchyma and completely destroyed small tumors and part of large tumors. Localized healing of the ablation and normalization of transaminases occurred within 7 days post RFA. RFA treatment extended the survival of small tumor-bearing mice. They survived at least 5 months longer than the controls; however, mice with larger tumors only had a slight therapeutic effect after RFA. Collectively, we performed RFA in murine HCCs and observed a significant therapeutic effect in small tumor-bearing mice. The quick recovery of tumor-bearing mice receiving RFA mimics observations in human subjects. This platform provides us a unique opportunity to study RFA in HCC treatment. PMID:26537481

  8. Radiofrequency ablation of hepatocellular carcinoma in patients with and without cirrhosis

    PubMed Central

    Salmi, A.; Turrini, R.; Lanzani, G.; Savio, A.; Anglani, L.

    2009-01-01

    Introduction Hepatocellular carcinoma (HCC) is a leading cause of death in patients with cirrhosis. Around 12% of all cases are associated with chronic liver disease without cirrhosis. The aim of our study was to compare primary tumor ablation rates, local tumor progression, safety, and long-term outcomes of radiofrequency ablation for single (less than 3.5 cm in diameter) or multiple HCC nodules (up to three nodules, each less than 3 cm) in both types of patients. Methods We treated 200 consecutive HCC patients recruited from a local sonographic screening program: 175 with cirrhosis and 25 with non-cirrhotic chronic liver disease. Results Complete ablation was achieved in 150 of the 175 patients (85.7%) (174 of the 206 nodules treated, 84.4%) in the cirrhotic group and in 24 of the 25 patients (96%) (27 of the 29 nodules treated; 93%) in the non-cirrhotic group. The two groups were not significantly different in terms of local tumor progression rates 1, 3, and 5 years after treatment (11%, 23%, and 24% among cirrhotics vs. 4%, 14%, and 14% among non-cirrhotic patients). Multifocal disease was more frequent among the cirrhotics. One-, three- and five-year survival rates were also similar in the cirrhotic (93%, 77%, and 61%) and non-cirrhotic groups (92%, 72%, and 64%). There were no treatment-related deaths. Severe complications occurred only in the cirrhotic group (2.2%). Conclusions Radiofrequency ablation is safe and effective treatment for HCC in patients with or without cirrhosis. The latter group has a significantly lower rate of multifocal disease. PMID:23396874

  9. Radiofrequency ablation compared to resection in early-stage hepatocellular carcinoma

    PubMed Central

    Tohme, Samer; Geller, David A.; Cardinal, Jon S.; Chen, Hui-Wei; Packiam, Vignesh; Reddy, Srinevas; Steel, Jennifer; Marsh, James W.; Tsung, Allan

    2013-01-01

    Objectives: This study aimed to compare survival outcomes after hepatic resection (HR) and radiofrequency ablation (RFA) in early-stage hepatocellular carcinoma (HCC) at a Western hepatobiliary centre. Methods: Demographic details, clinicopathologic tumour characteristics and survival outcomes were compared among non-transplant candidate patients undergoing HR (n= 50) and RFA (n= 60) for early-stage HCC during 2001–2011. Results: Patients who underwent HR had larger tumours, a longer length of stay and a higher rate of postoperative complications. After a median follow-up of 29 months, there were no significant differences between the treatment groups in 1-, 3- and 5-year overall survival (OS) [RFA group: 86%, 50%, 35%, respectively; HR group: 88%, 68%, 47%, respectively (P= 0.222)] or disease-free survival (DFS) [RFA group: 68%, 42%, 28%, respectively; HR group: 66%, 42%, 34%, respectively (P= 0.823)]. The 58 patients who underwent RFA demonstrated ablation success on follow-up computed tomography at 3 months. Of these, 96.5% of patients showed sustained ablation success over the entire follow-up period. In a subgroup analysis of patients with tumours measuring 2–5 cm, no differences in OS or DFS emerged between the HR and RFA groups. Similarly, no significant differences in outcomes in patients with Child–Pugh class A cirrhosis were seen between the RFA and HR groups. Conclusions: Radiofrequency ablation is comparable with HR in terms of OS and DFS. It is a reasonable alternative as a first-line treatment for HCC in well-selected patients who are not candidates for transplant. PMID:23374361

  10. Toward guidance of epicardial cardiac radiofrequency ablation therapy using optical coherence tomography

    PubMed Central

    Fleming, Christine P.; Quan, Kara J.; Rollins, Andrew M.

    2010-01-01

    Radiofrequency ablation (RFA) is the standard of care to cure many cardiac arrhythmias. Epicardial ablation for the treatment of ventricular tachycardia has limited success rates due in part to the presence of epicardial fat, which prevents proper rf energy delivery, inadequate contact of ablation catheter with tissue, and increased likelihood of complications with energy delivery in close proximity to coronary vessels. A method to directly visualize the epicardial surface during RFA could potentially provide feedback to reduce complications and titrate rf energy dose by detecting critical structures, assessing probe contact, and confirming energy delivery by visualizing lesion formation. Currently, there is no technology available for direct visualization of the heart surface during epicardial RFA therapy. We demonstrate that optical coherence tomography (OCT) imaging has the potential to fill this unmet need. Spectral domain OCT at 1310 nm is employed to image the epicardial surface of freshly excised swine hearts using a microscope integrated bench-top scanner and a forward imaging catheter probe. OCT image features are observed that clearly distinguish untreated myocardium, ablation lesions, epicardial fat, and coronary vessels, and assess tissue contact with catheter-based imaging. These results support the potential for real-time guidance of epicardial RFA therapy using OCT imaging. PMID:20799788

  11. Characterization of radiofrequency ablation lesion development based on simulated and measured intracardiac electrograms.

    PubMed

    Keller, Matthias Walter; Schuler, Steffen; Wilhelms, Mathias; Lenis, Gustavo; Seemann, Gunnar; Schmitt, Claus; Dössel, Olaf; Luik, Armin

    2014-09-01

    Radiofrequency ablation (RFA) therapy is the gold standard in interventional treatment of many cardiac arrhythmias. A major obstacle is nontransmural lesions, leading to recurrence of arrhythmias. Recent clinical studies have suggested intracardiac electrogram (EGM) criteria as a promising marker to evaluate lesion development. Seeking for a deeper understanding of underlying mechanisms, we established a simulation approach for acute RFA lesions. Ablation lesions were modeled by a passive necrotic core surrounded by a borderzone with properties of heated myocardium. Herein, conduction velocity and electrophysiological properties were altered. We simulated EGMs during RFA to study the relation between lesion formation and EGM changes using the bidomain model. Simulations were performed on a three-dimensional setup including a geometrically detailed representation of the catheter with highly conductive electrodes. For validation, EGMs recorded during RFA procedures in five patients were analyzed and compared to simulation results. Clinical data showed major changes in the distal unipolar EGM. During RFA, the negative peak amplitude decreased up to 104% and maximum negative deflection was up to 88% smaller at the end of the ablation sequence. These changes mainly occurred in the first 10 s after ablation onset. Simulated unipolar EGMs reproduced the clinical changes, reaching up to 83% negative peak amplitude reduction and 80% decrease in maximum negative deflection for transmural lesions. In future studies, the established model may enable the development of further EGM criteria for transmural lesions even for complex geometries in order to support clinical therapy. PMID:24816474

  12. Nanobubble Ultrasound Contrast Agents for Enhanced Delivery of Thermal Sensitizer to Tumors Undergoing Radiofrequency Ablation

    PubMed Central

    Perera, Reshani H.; Solorio, Luis; Wu, Hanping; Gangolli, Mihika; Silverman, Eric; Hernandez, Christopher; Peiris, Pubudu M.; Broome, Ann-Marie

    2013-01-01

    Purpose Pluronic has been shown to sensitize various tumor cell lines to chemotherapy and hyperthermia by altering the membrane fluidity, depleting ATP, and modulating the heat shock protein 70 expression. In our prior work, Pluronic was also used to formulate nanosized ultrasound contrast agents. In the current study we evaluate the use of these contrast agents as vehicles for image-guided delivery of Pluronic to improve outcomes of tumor radiofrequency (RF) ablation. Methods Lipid-shelled Pluronic nanobubbles were prepared and examined for size distribution, zeta potential, stability, biodistribution, accumulation of nanobubbles in the tumor, and treatment efficacy. LS174-T xenograft tumor-bearing mice were used to evaluate tumor growth suppression and measure treatment efficacy after RF ablation. Results The average diameter of Pluronic bubbles was 230 nm, and initial bubble echogenicity was 16 dB. In vitro, cells exposed to Pluronic nanobubbles exhibited low cytotoxicity in the absence of ultrasound, even if heat (43°C) was applied. When the cells were exposed to Pluronic nanobubbles, heat, and ultrasound; viability was significantly reduced. In vivo, tumors treated with ultrasound-modulated nanobubbles prior to RF ablation showed a significant reduction in growth compared to the RF alone (P<0.05). Conclusion Lipid and Pluronic-shelled, echogenic nanobubbles combined with ultrasound modulation can serve as an effective theranostic method for sensitization of tumors to RF ablation. PMID:23943542

  13. Toward guidance of epicardial cardiac radiofrequency ablation therapy using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Fleming, Christine P.; Quan, Kara J.; Rollins, Andrew M.

    2010-07-01

    Radiofrequency ablation (RFA) is the standard of care to cure many cardiac arrhythmias. Epicardial ablation for the treatment of ventricular tachycardia has limited success rates due in part to the presence of epicardial fat, which prevents proper rf energy delivery, inadequate contact of ablation catheter with tissue, and increased likelihood of complications with energy delivery in close proximity to coronary vessels. A method to directly visualize the epicardial surface during RFA could potentially provide feedback to reduce complications and titrate rf energy dose by detecting critical structures, assessing probe contact, and confirming energy delivery by visualizing lesion formation. Currently, there is no technology available for direct visualization of the heart surface during epicardial RFA therapy. We demonstrate that optical coherence tomography (OCT) imaging has the potential to fill this unmet need. Spectral domain OCT at 1310 nm is employed to image the epicardial surface of freshly excised swine hearts using a microscope integrated bench-top scanner and a forward imaging catheter probe. OCT image features are observed that clearly distinguish untreated myocardium, ablation lesions, epicardial fat, and coronary vessels, and assess tissue contact with catheter-based imaging. These results support the potential for real-time guidance of epicardial RFA therapy using OCT imaging.

  14. The clinical experience and efficacy of bipolar radiofrequency with fractional photothermolysis for aged Asian skin.

    PubMed

    Akita, Hirotaka; Sasaki, Ryosuke; Yokoyama, Yusuke; Negishi, Kei; Matsunaga, Kayoko

    2014-10-01

    Bipolar radiofrequency (RF) technology is developed based on fractional thermolysis, and the literature concerning the efficacy of the rejuvenation and treatment of acne scars has been reported in Europe and the United States of America. Therefore, we examined bipolar RF treatment using fractional thermolysis to evaluate the efficacy and safety of the treatment of Asian photo-aging skin, particularly 'wrinkles' and 'sagging.' Ten Japanese women (mean age: 58.6, skin type III-IV) received three fractional bipolar RF treatments every 4-6 weeks. For the objective evaluation, we evaluated the improvement of the wrinkles on the forehead, lateral canthus (crow's feet) and lower eyelid, and the sagging of the nasolabial fold using digital photographs captured using Visia(™) . For the subjective evaluation, the participants were asked to describe the improvements observed in the wrinkles on the forehead, lateral canthus (crow's feet) and lower eyelid, and sagging nasolabial fold and to evaluate the level pain experienced using a 10-point VAS score. The objective evaluation in each category showed significant improvements in the wrinkles on the lateral canthus (crow's feet) and lower eyelid. As for the nasolabial fold, 60% of the subjects showed improvements, scoring from good to excellent (51-100% improvement), although there was a little improvement of the wrinkle on the forehead. Similar improvements were observed in the subjective evaluation. During each treatment, oedema and erythema were observed in all participants, but the oedema disappeared the following day in all cases. However, mild erythema persisted for an average of 3.1 days. Micro debris disappeared after an average of 5.2 days. The participants were satisfied, as we allowed them to apply make-up the next day. There were no other severe adverse reactions observed during the treatment. The 10-point VAS score was 3.8, and no participants dropped out due to discomfort. Little improvement was observed in

  15. Radiofrequency ablation of benign thyroid nodules: evaluation of the treatment efficacy using ultrasonography

    PubMed Central

    2016-01-01

    Purpose: The aim of this study was to evaluate the efficacy of radiofrequency (RF) ablation for benign thyroid nodules and assess the usefulness of internal factors (ultrasonographic findings) and external factors (treatment-related findings) in prediction of treatment efficacy. Methods: We evaluated 22 benign thyroid nodules from 19 patients treated with RF ablation between March 2010 and January 2013. The internal and external factors of these nodules were retrospectively reviewed and correlated with the therapeutic success and the volume reduction ratio (VRR). The volume and size of the nodules were determined before treatment, and the VRR was calculated at 6-month and 1-year follow-up examinations after RF ablation. Therapeutic success was defined as a >50% volume reduction. Results: The mean VRRs were 66.1±18.7% at 6 months and 74.3±16.7% at 1 year. The therapeutic success rate after 6 months and 1 year was 81.8% and 90.9%, respectively. At the 1-year follow-up, the margin of the nodule correlated with therapeutic success. Most of the successfully ablated nodules showed well-defined margins on initial ultrasonography (18/20, 90%) (P=0.026). In addition, nodules with ill-defined margins showed a tendency toward having a low VRR at the 6-month and 1-year follow-up examinations. Conclusion: RF ablation was effective in decreasing the volume of benign thyroid nodules. Thyroid nodules with well-defined margins tended to show successful outcomes at the 1-year follow-up examination after RF ablation. PMID:27101983

  16. Radiofrequency ablation for lung tumors: outcomes, effects on survival, and prognostic factors

    PubMed Central

    Akhan, Okan; Güler, Ezgi; Akıncı, Devrim; Çiftçi, Türkmen; Köse, Ilgaz Çağatay

    2016-01-01

    PURPOSE We aimed to evaluate the survival benefit achieved with radiofrequency (RF) ablation of primary and metastatic lung tumors and determine significant prognostic factors for recurrence-free survival. METHODS Forty-nine patients with lung cancer (10 primary and 39 metastatic) underwent computed tomography-guided percutaneous RF ablation between June 2005 and October 2013. A total of 112 tumors (101 metastatic and 11 primary non-small cell lung cancer) were treated with RF ablation. Tumor diameter ranged from 0.6 to 4 cm (median 1.5 cm). Effectiveness of treatment, complications, and survival were analyzed. RESULTS Primary success rate was 79.5% and local tumor progression occurred in 23 tumors. Among tumors showing progression, 10 were re-treated with RF ablation and secondary success rate was 87.5%. One-, two-, and three-year overall survival rates of 10 patients with primary lung cancer were 100%, 86%, and 43%, respectively. One-, two-, three-, four-, and five-year overall survival rates for 39 patients with metastatic lung tumors were 90%, 73%, 59%, 55%, and 38%, respectively. One-, two-, three-, and four-year overall survival rates for 16 patients with colorectal pulmonary metastases were 94%, 80%, 68%, and 23%, respectively. Complications occurred in 30 sessions (24.6%). Pneumothorax occurred in 19 sessions with seven requiring image-guided percutaneous chest tube drainage. Tumor status (solitary or multiple) and presence of extrapulmonary metastasis at initial RF ablation were significant prognostic factors in terms of recurrence-free survival. CONCLUSION RF ablation is a safe and effective treatment with a survival benefit for selected patients with primary and secondary lung tumors. PMID:26611111

  17. Radiofrequency Ablation of Rabbit Liver In Vivo: Effect of the Pringle Maneuver on Pathologic Changes in Liver Surrounding the Ablation Zone

    PubMed Central

    Kim, Seung Kwon; Ryu, Jeong-ah; Choi, Dongil; Lee, Won Jae; Lee, Ji Yeon; Lee, Ju Hyun; Sung, Yon Mi; Cho, Eun Yoon; Hong, Seung-Mo; Kim, Jong-Sung

    2004-01-01

    Objective We wished to evaluate the effect of the Pringle maneuver (occlusion of both the hepatic artery and portal vein) on the pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone in rabbit livers. Materials and Methods Radiofrequency (RF) ablation zones were created in the livers of 24 rabbits in vivo by using a 50-W, 480-kHz monopolar RF generator and a 15-gauge expandable electrode with four sharp prongs for 7 mins. The tips of the electrodes were placed in the liver parenchyma near the porta hepatis with the distal 1 cm of their prongs deployed. Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver. Three animals of each group were sacrificed immediately, three days (the acute phase), seven days (the early subacute phase) and two weeks (the late subacute phase) after RF ablation. The ablation zones were excised and serial pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone were evaluated. Results With the Pringle maneuver, portal vein thrombosis was found in three cases (in the immediate [n=2] and acute phase [n=1]), bile duct dilatation adjacent to the ablation zone was found in one case (in the late subacute phase [n=1]), infarction adjacent to the ablation zone was found in three cases (in the early subacute [n=2] and late subacute [n=1] phases). None of the above changes was found in the livers ablated without the Pringle maneuver. On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05) Conclusion Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma

  18. Usefulness of a New Three-Dimensional Simulator System for Radiofrequency Ablation

    PubMed Central

    Hirooka, Masashi; Koizumi, Yohei; Imai, Yusuke; Miyake, Teruki; Watanabe, Takao; Yoshida, Osamu; Takeshita, Eiji; Tokumoto, Yoshio; Abe, Masanori; Hiasa, Yoichi

    2016-01-01

    Multipuncture radiofrequency ablation is expected to produce a large ablated area and reduce intrahepatic recurrence of hepatocellular carcinoma; however, it requires considerable skill. This study evaluated the utility of a new simulator system for multipuncture radiofrequency ablation. To understand positioning of multipuncture electrodes on three-dimensional images, we developed a new technology by expanding real-time virtual ultrasonography. We performed 21 experimental punctures in phantoms. Electrode insertion directions and positions were confirmed on computed tomography, and accuracy and utility of the simulator system were evaluated by measuring angles and intersections for each electrode. Moreover, to appropriately assess placement of the three electrodes, puncture procedures with or without the simulator were performed by experts and non-experts. Technical success was defined as maximum angle and distance ratio, as calculated by maximum and minimum distances between electrodes. In punctures using 2 electrodes, correlations between angles on each imaging modality were strong (ultrasound vs. simulator: r = 0.991, p<0.001, simulator vs. computed tomography: r = 0.991, p<0.001, ultrasound vs. computed tomography: r = 0.999, p<0.001). Correlations between distances in each imaging modality were also strong (ultrasound vs. simulator: r = 0.993, p<0.001; simulator vs. computed tomography: r = 0.994, p<0.001; ultrasound vs. computed tomography: r = 0.994, p<0.001). In cases with 3 electrodes, distances between each electrode correlated strongly (yellow-labeled vs. red-labeled: r = 0.980, p<0.001; red-labeled vs. blue-labeled: r = 0.953, p<0.001; yellow-labeled vs. blue-labeled: r = 0.953, p<0.001). Both angle and distance ratio (expert with simulator vs. without simulator; p = 0.03, p = 0.02) were significantly smaller in procedures performed by experts using the simulator system. The new simulator system appears to accurately guide electrode positioning. This

  19. The Feasibility of Hepatic Resections Using a Bipolar Radiofrequency Device (Habib®).

    PubMed

    Civil, Osman; Kement, Metin; Okkabaz, Nuri; Haksal, Mustafa; Gezen, Cem; Oncel, Mustafa

    2015-08-01

    The bipolar radiofrequency device (Habib®) has been recently introduced in order to reduce intraoperative bleeding for a safe hepatic resection as an alternative to the conventional tools. However, indications, perioperative findings, and outcome of the device for hepatic resections remain and deserve to be analyzed. The current study aims to analyze the feasibility of the bipolar radiofrequency device (Habib®) for hepatic resections. Information of the patients that underwent hepatic resection using with the Habib® device between 2007 and 2011 was abstracted. Patient, disease, and operation-related findings and perioperative data were investigated. A total of 71 cases (38 [53.5 %] males, mean age was 56.8 ± 11.9) were analyzed. Metastatic disease (n = 55; 77.5 %) was the leading indication followed by primary liver and biliary malignancies (n = 7; 9.9 %), hemangioma (n = 5; 7 %), hydatid disease (n = 3; 2.8 %), and hepatic gunshot trauma (n = 1; 1.4 %). Metastasectomy was the most commonly performed procedure (n = 31; 56.3 %), but in 24 (77.4 %) cases, it was performed in addition to extended resections. Other procedures in the study patients include segmentectomy in 17, bisegmentectomy in 19, trisegmentectomy in 17, right or left hepatectomy in 8, and extended right/left hepatectomy in 3. The mean (±SD) operation time was 241.7 ± 78.2 min. The median amount of bleeding was 300 cc (range 25-2500), and 23 (32.4 %) cases required perioperative transfusion. The median hospitalization period was 5 days (range 1-47). Lengthened drainage (n = 9, 12.7 %) and intraabdominal abscess (n = 8, 11.23 %) were the most common problems. Hepatic resections using the Habib® device seem to be feasible in cases with primary and metastatic hepatic lesions and benign liver masses and even those with hepatic trauma. It may lessen the amount of intraoperative hemorrhage, although lengthened drainage and intraabdominal abscess

  20. Intermediate-term results of partial plantar fascia release with microtenotomy using bipolar radiofrequency microtenotomy.

    PubMed

    Lucas, Douglas E; Ekroth, Scott R; Hyer, Christopher F

    2015-01-01

    Plantar fasciitis is a common condition, with most patients treated successfully with nonoperative management. Recalcitrant disease has been managed with surgical procedures that vary in design and associated morbidity. The present study sought to determine the intermediate-term results of percutaneous bipolar radiofrequency microtenotomy in recalcitrant plantar fasciitis. The patient medical records were reviewed, and data were gathered for all the patients who met the inclusion criteria. The foot function index and visual analog scale (VAS) pain scale questionnaires were mailed to the 111 patients. Of the 111 patients, 61 (55.0%) returned their questionnaires and were ultimately included in the present analysis. Of the 61 patients, 44 (72.1%) were female and 17 were (27.9%) male, with an average reported follow-up of 33.3 ± 8.6 (range 16.1 to 46.6) months. The median postoperative VAS score was 0.0 (range 0.0 to 10.0), and the median foot function index score was 3.1 (range 0.0 to 97.1). The patients were subdivided into success and failure groups according to their satisfaction. Of the 61 patients, 51 (83.6%) were satisfied and would recommend the procedure to a friend. The median VAS score in the success group was 0.0 (range 0.0 to 5.0), and the median VAS score in the failure group was 6.0 (range 0.0 to 10.0), a significant difference (p < .001). A significant difference was also seen in the foot function index score between the success (median 2.4, range 0.0 to 25.7) and failure (median 37.4, range 0.0 to 97.1) groups (p < .001). Bipolar radiofrequency microtenotomy appears to be a safe procedure that can provide outcomes equivalent to those with open surgery, with less morbidity, for recalcitrant plantar fasciitis. PMID:25617155

  1. Radiofrequency ablation of renal tumours with clinical, radiographical and pathological results

    PubMed Central

    Karam, Jose A.; Ahrar, Kamran; Vikram, Raghunandan; Romero, Claudio A.; Jonasch, Eric; Tannir, Nizar M.; Rao, Priya; Wood, Christopher G.; Matin, Surena F.

    2012-01-01

    Objectives To evaluate our experience with radiofrequency ablation (RFA) for renal masses and to report on clinical, radiological and post-RFA biopsy results. Patients and methods The study collected clinical, radiological and pathological data from 150 consecutive patients who were treated with RFA of a renal mass between 2002 and 2008 at a tertiary referral centre. Post-ablation biopsies were performed in patients with non-involuting lesions or suspicion of recurrence on imaging. Comparisons were performed using the Mann–Whitney U-test. Survival was estimated using the Kaplan–Meier method. Results Renal malignancy was found in 72.1% of patients based on the initial diagnostic biopsy. Median tumour size was 2.6 cm, 22.7% of patients had a solitary kidney, and most were central tumours. The mean follow-up period was 40.1 months. There was no recurrence in 96.7% of the entire cohort. Cancer-specific survival for 106 patients with sporadic, localized, biopsy proven renal malignancy was 100% at 38.5 months. Biopsies were obtained in 43 patients for a median of 21 months after RFA. Among 38 patients who had biopsy for non-involuting, non-enhancing zones of ablation, three (7.9%) were positive. Conclusions Short-term cancer-specific survival after RFA remains excellent and most cases are successful based on a combination of imaging and post-ablation biopsies performed almost 2 years after treatment. There were four out of 150 (2.7%) patients who had recurrences with tissue confirmation; one of these patients was detected on imaging and three (2%) were radiologically occult. The absence of enhancement in the setting of non-involuting lesions is not always a guarantee of a successful ablation. PMID:23510233

  2. Radiofrequency ablation for single hepatocellular carcinoma 3 cm or less as first-line treatment

    PubMed Central

    Gao, Jun; Wang, Shao-Hong; Ding, Xue-Mei; Sun, Wen-Bing; Li, Xiao-Long; Xin, Zong-Hai; Ning, Chun-Min; Guo, Shi-Gang

    2015-01-01

    AIM: To evaluate long-term outcomes of radiofrequency (RF) ablation as first-line therapy for single hepatocellular carcinoma (HCC) ≤ 3 cm and to determine survival and prognostic factors. METHODS: We included all 184 patients who underwent RF ablation as a first-line treatment for single HCC ≤ 3 cm between April 2005 and December 2013. According to the criteria of Livraghi, the 184 patients were divided into two groups: those suitable for surgical resection (84 cases) and those unsuitable for surgical resection (100 cases). The primary endpoints were the overall survival (OS) rate and safety; the secondary endpoints were primary technique effectiveness and recurrence rate. RESULTS: There were 19 (10.3%) cases of ablation related minor complications. The complete tumor ablation rate after one RF session was 97.8% (180/184). The rate of local tumor progression, extrahepatic metastases and intrahepatic distant recurrence were 4.9% (9/184), 9.8% (18/184) and 37.5% (69/184), respectively. In the 184 patients, the 1-, 3-, and 5-year OS rates were 99.5%, 81.0%, and 62.5%, respectively. The 1-, 3-, and 5-year OS rates were 100%, 86.9%, and 71.4%, respectively, in those suitable for surgical resection and 99.0%, 76.0%, and 55.0%, respectively, in those unsuitable for surgical resection (P = 0.021). On univariate and multivariate analyses, poorer OS was associated with Child-Pugh B class and portal hypertension (P < 0.05). CONCLUSION: RF ablation is a safe and effective treatment for single HCC ≤ 3 cm. The OS rate of patients suitable for surgical resection was similar to those reported in surgical series. PMID:25954102

  3. Radiofrequency Ablation in the Management of Advanced Stage Thymomas: A Case Report on a Novel Multidisciplinary Therapeutic Approach

    PubMed Central

    Pala, Carlo; Versace, Renato

    2014-01-01

    We describe in this report a case of successful radiofrequency ablation of an unresectable stage III-type B3 thymoma, and we discuss the role of this novel approach in the management of patients with advanced stage thymoma. The patient, a 59-year-old Caucasian male underwent neoadjuvant chemotherapy with only a slight reduction of the mass. Subsequently, an explorative sternotomy and debulking were performed; before closing the thorax, radiofrequency ablation of the residual tumor was carried out and a partial necrosis of the mass was achieved. A further percutaneous radiofrequency ablation was performed subsequently, obtaining complete necrosis of the lesion. Successively, the patient underwent adjuvant radiotherapy. As a result of this multidisciplinary treatment, complete and stable response was obtained. It is hard to say which of the single treatments had the major impact on cure; nevertheless, the results obtained suggest that radiofrequency ablation must be taken into account for the treatment of advanced stage thymomas, and its effectiveness must be further assessed in future studies. PMID:25574416

  4. Characterization of Acute and Subacute Radiofrequency Ablation Lesions with Non-enhanced Magnetic Resonance Imaging

    PubMed Central

    Dickfeld, Timm; Kato, Ritsushi; Zviman, Menekem; Nazarian, Saman; Dong, Jun; Ashikaga, Hiroshi; Lardo, Albert C.; Berger, Ronald D.; Calkins, Hugh; Halperin, Henry

    2007-01-01

    Background MRI has the potential to visualize radiofrequency ablations (RFA), which have become the preferred treatment strategy for many arrhythmias. However, MRI patterns after RFA have not been well investigated. Objective This study sought to define the characteristic appearance and the effect of time and energy on non-contrast-enhanced MR imaging of RFA. Methods Using a power-controlled, cooled tip ablation system, RFA (5W–50W for 45s) were created on the right ventricular epicardium in 10 mongrel dogs. T1- and T2-weighted MR images were obtained during a 12-hours follow-up and compared to gross anatomy and histopathology. Results Lesions were successfully visualized with T2- and T1-weighted images 30min to 12 hours after RFA. T2 images were more consistent and displayed a characteristic elliptical, high-signal core (Contrast-to-noise-ratio [CNR] =18.9 ± 8.4) with a surrounding 0.5 mm low-intensity rim, which corresponded on histopathology to the central tissue necrosis and the transition zone, respectively. T1 images showed a less remarked increase in signal intensity (CNR=9.6 ± 7.4) without surrounding rim. Lesion size and appearance were well defined and unchanged during the 12 hours follow-up (ANOVA). CNR was independent of applied RF energy and allowed accurate assessment of the RFA at all time points (r=0.87 and r=0.83 for T2/T1 images, respectively). Transmural lesions, interlesional gaps and intralesional pathology could be reliably predicted in >90%. Conclusion Non-contrast-enhanced MRI allows accurate assessment of RFA and its intra-lesional pathology during a 12h follow-up. This confirms a possible role for MRI in guiding and evaluating RF application during electrophysiological ablation procedures. CONDENSED ABSTRACT MRI can visualize heat-induced tissue damage and its associated histological changes such as interstitial edema or protein necrosis through changes in T1- and T2-relaxation parameters. This study demonstrates that the

  5. The influence of radiofrequency ablation patterns on length, histological and mechanical properties of tendons

    PubMed Central

    Oron, Amir; Reshef, Noam; Beer, Yiftah; Brosh, Tamar; Agar, Gabriel

    2012-01-01

    Summary The use of radiofrequency ablation for thermomodulation of connective tissues has gained acceptance with some surgeons. It is now mainly used for shoulder instability, and two techniques are commonly applied – ablation in a uniform pattern (paintbrush) and ablation in a linearly dispersed fashion (grid). The use of these techniques for shrinkage of tendons or cruciate ligaments is not widely accepted but may be utilized in selected cases. We assessed the effects of thermo-modulation via monopolar radiofrequency ablation using these two techniques on the histological and biomechanical properties of rabbit Achilles tendons. 16 paired rabbit achilles tendons were divided into two treatment groups. Using a Monopolar RF device, eight tendons were treated using the paintbrush technique, and eight using the grid technique. The tendons were shrunk to about 90% of their original length, and the paired tendons were used as control. Following thermomodulation, tendons were pulled to tear using the Instron 4502 (Instron, Mass.) device. We found treated tendons were significantly less resistant to tear when compared to control; the average load to failure of the treatment group was 19.4% lower (p=0.05) than the control group values and the average tissue stiffness in the treatment group was 11.3% lower (p=0.051) than the control group. We found a tendency towards a lower resistance to pull in the tendon group treated using the grid technique. Histological analysis demonstrated areas of collagen denaturation correlated to areas of thermomodulation. A random point of failure was found along the tendons in the paintbrush group whereas the typical point of failure in the grid group was located at the treatment point or at its margins. Our findings demonstrate that use of the grid technique in ablation of tendons creates typical failure points (locus minoris resistenci) which bring about failure and alter the biomechanical properties of the thermomodulated tendons

  6. Fatal Diaphragmatic Hernia following Radiofrequency Ablation for Hepatocellular Carcinoma: A Case Report and Literature Review

    PubMed Central

    Saito, Tomoko; Chiba, Tetsuhiro; Ogasawara, Sadahisa; Inoue, Masanori; Wakamatsu, Toru; Motoyama, Tenyu; Kanogawa, Naoya; Suzuki, Eiichiro; Ooka, Yoshihiko; Tawada, Akinobu; Matsubara, Hisahiro; Yokosuka, Osamu

    2015-01-01

    An 81-year-old man was admitted to our hospital because of right quadrant abdominal pain. On admission, his liver function was Child-Pugh grade C (10 points). Computed tomography (CT) revealed a diaphragmatic herniation of bowel loops into the right thoracic cavity, accompanied by pleural effusion. Although diaphragmatic hernia was successfully repaired by emergency surgery, he died of liver failure 23 days after the surgery. A retrospective reading of CT images revealed the presence of diaphragmatic injury after radiofrequency ablation (RFA) which had been conducted 33 months before the development of diaphragmatic hernia. Of importance, the lesion of the diaphragmatic injury was located on the estimated needle track of RFA for hepatocellular carcinomas in segment 5 and segment 5/8, but not adjacent to their ablation areas. Subsequently, diaphragmatic perforation had been observed 24 months before admission. This suggests that diaphragmatic hernia caused by RFA is not necessarily due to thermal damage of ablation and is possibly life-threatening, at least in some patients with an impaired liver function. PMID:26120308

  7. Lesion size estimator of cardiac radiofrequency ablation at different common locations with different tip temperatures.

    PubMed

    Lai, Yu-Chi; Choy, Young Bin; Haemmerich, Dieter; Vorperian, Vicken R; Webster, John G

    2004-10-01

    Finite element method (FEM) analysis has become a common method to analyze the lesion formation during temperature-controlled radiofrequency (RF) cardiac ablation. We present a process of FEM modeling a system including blood, myocardium, and an ablation catheter with a thermistor embedded at the tip. The simulation used a simple proportional-integral (PI) controller to control the entire process operated in temperature-controlled mode. Several factors affect the lesion size such as target temperature, blood flow rate, and application time. We simulated the time response of RF ablation at different locations by using different target temperatures. The applied sites were divided into two groups each with a different convective heat transfer coefficient. The first group was high-flow such as the atrioventricular (AV) node and the atrial aspect of the AV annulus, and the other was low-flow such as beneath the valve or inside the coronary sinus. Results showed the change of lesion depth and lesion width with time, under different conditions. We collected data for all conditions and used it to create a database. We implemented a user-interface, the lesion size estimator, where the user enters set temperature and location. Based on the database, the software estimated lesion dimensions during different applied durations. This software could be used as a first-step predictor to help the electrophysiologist choose treatment parameters. PMID:15490835

  8. Hepatic radiofrequency ablation with internally cooled probes: effect of coolant temperature on lesion size.

    PubMed

    Haemmerich, Dieter; Chachati, Louay; Wright, Andrew S; Mahvi, David M; Lee, Fred T; Webster, John G

    2003-04-01

    Radiofrequency (RF) ablation is a minimally invasive method for treatment of primary and metastatic liver tumors. One of the currently commercially available devices employs an internally cooled 17-gauge needle probe. Within the probe, cool water is circulated during ablation, which cools tissue close to the probe resulting in larger lesions. We evaluated the effect of different cooling water temperatures on lesion size. We created a finite-element method model, simulated 12 min impedance-controlled ablation and determined temperature distribution for three water temperatures. Lesion diameters in the model were 33.8, 33.4, and 32.8 mm for water temperatures of 5 degrees C, 15 degrees C, and 25 degrees C, respectively. We solved a simplified model geometry analytically and present dependence of lesion diameter on cooling temperature. We further performed ex vivo experiments in fresh bovine liver. We created four lesions for each water temperature, with the same water temperatures as used in the finite-element method (FEM) model. Average lesion diameters were 28.3, 30, and 29.5 mm for water temperatures of 5 degrees C, 15 degrees C, and 25 degrees C, respectively. Water temperature did not have a significant effect on lesion size in the ex vivo experiments (p = 0.76), the FEM model, and the analytical solution. PMID:12723061

  9. [Effect of radiofrequency ablation of accessory atrio-ventricular junctions on electromechanical coupling of the myocardium in children with manifesting Wolf-Parkinson-White syndrome].

    PubMed

    Martsinkevich, G I; Sokolov, A A; Murzina, O Iu; Kovalev, I A; Popov, S V

    2007-01-01

    Aim of the study was to assess immediate and remote hemodynamic and electromechanical effects of radiofrequency ablation of accessory atrio-ventricular pathways in children with manifesting Wolf-Parkinson-White (WPW) syndrome. Radiofrequency ablation of accessory atrio-ventricular pathways resulted in diminishment of intraventricular dyssynchrony, what appeared as lowering of the degree of heterogeneity of electromechanical intervals and was associated with significant augmentation of left ventricular stroke volume. Presence of pronounced intraventricular asynchrony might be an additional indication to radiofrequency ablation of accessory atrio-ventricular pathways in patients with WPW syndrome without history of documented attacks of tachycardia. PMID:18260859

  10. Radiofrequency Ablation Therapy Combined with Cementoplasty for Painful Bone Metastases: Initial Experience

    SciTech Connect

    Toyota, Naoyuki Naito, Akira; Kakizawa, Hideaki; Hieda, Masashi; Hirai, Nobuhiko; Tachikake, Toshihiro; Kimura, Tomoki; Fukuda, Hideki; Ito, Katsuhide

    2005-06-15

    The purpose of this study was to assess the efficacy and safety of percutaneous radiofrequency (RF) ablation therapy combined with cementoplasty under computed tomography and fluoroscopic guidance for painful bone metastases. Seventeen adult patients with 23 painful bone metastases underwent RF ablation therapy combined with cementoplasty during a 2-year period. The mean tumor size was 52 x 40 x 59 mm. Initial pain relief, reduction of analgesics, duration of pain relief, recurrence rate of pain, survival rate, and complications were analyzed. The technical success rate was 100%. Initial pain relief was achieved in 100% of patients (n = 17). The mean VAS scores dropped from 63 to 24 (p < 0.001) (n = 8). Analgesic reduction was achieved in 41% (7 out of 17 patients). The mean duration of pain relief was 7.3 months (median: 6 months). Pain recurred in three patients (17.6%) from 2 weeks to 3 months. Eight patients died and 8 patients are still alive (a patient was lost to follow-up). The one-year survival rate was 40% (observation period: 1-30 months). No major complications occurred, but one patient treated with this combined therapy broke his right femur 2 days later. There was transient local pain in most cases, and a hematoma in the psoas muscle (n = 1) and a hematoma at the puncture site (n = 1) occurred as minor complications. Percutaneous RF ablation therapy combined with cementoplasty for painful bone metastases is effective and safe, in particular, for bulky tumors extending to extraosseous regions. A comparison with cementoplasty or RF ablation alone and their long-term efficacies is needed.