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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 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

  4. 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

  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 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

  2. 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

  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. 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.

  11. 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

  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 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

  7. 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

  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. 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

  18. 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.

  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. 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.

  2. 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).

  3. [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

  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 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

  7. 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

  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. 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

  20. 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

  1. 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

  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. 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.

  6. 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

  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. 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.

  10. 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

  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 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

  16. 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

  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. 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

  5. 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.

  6. 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.

  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. 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.

  18. 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

  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. 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

  1. 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

  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. 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

  10. 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

  11. 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

  12. 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

  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

    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

  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. 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

  18. 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

  19. 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

  20. 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).

  1. 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

  2. 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

  3. 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

  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 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

  9. 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

  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. 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.

  12. 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

  13. 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

  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. 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

  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. 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

  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. 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

  5. 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

  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.

  11. Comparison of Two Techniques for Radio-frequency Hepatic Tumor Ablation through Numerical Simulation

    NASA Astrophysics Data System (ADS)

    Kosturski, N.; Margenov, S.; Vutov, Y.

    2011-11-01

    We simulate the thermal and electrical processes, involved in the radio-frequency ablation procedure. In this study, we take into account the observed fact, that the electrical conductivity of the hepatic tissue varies during the procedure. With the increase of the tissue temperature to a certain level, a sudden drop of the electrical conductivity is observed. This variation was neglected in some previous studies. 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 simulations were performed on the IBM Blue Gene/P massively parallel computer.

  12. Initial report of PET/CT-guided radiofrequency ablation of liver metastases.

    PubMed

    Prior, John O; Kosinski, Marek; Delaloye, Angelika Bischof; Denys, Alban

    2007-06-01

    Computed tomography (CT) and ultrasonography (US) are commonly employed to guide positioning of radiofrequency electrodes within target tumors. However, this technique cannot be used when the tumor is detectable only by positron emission tomography (PET). In such cases, even the use of intraprocedural coregistered PET/CT will not prevent malpositioning of the electrode tip relative to a lesion visualized only on PET as a result of patient breathing and organ shifts during CT-guided electrode placement. The present report describes a single case of successful targeting and complete ablation of a lesion invisible on CT and US with the use of a method to visualize electrode tip positioning by PET. PMID:17538147

  13. [Radiofrequency catheter ablation of two accessory pathways in patients with WPW Syndrome].

    PubMed

    Kalarus, Z; Kowalski, O; Prokopczuk, J; Chodór, P; Sredniawa, B; Pasyk, S

    1998-12-01

    In 10-30% patients with WPW syndrome more than one accessory pathway in electrophysiology study is observed. These patients make a group of higher atrial fibrillation and coming next ventricle fibrillation risk. We present the 39 years old patient with symptomatic WPW syndrome, without preexcitation signs in ECG at rest. In medical history--palpitations was observed from childhood with one episode of atrial fibrillation with high ventricle response required cardioversion. Electrophysiology study: without preexcitation signs at rest, two ortodromic AV reentrant tachycardias were induced--200 and 166/min. Two accessory pathways were diagnosed, left lateral and left midseptal. Radiofrequency catheter ablation of both accessory pathways was made during tachycardia, first lateral, next septal. In six month follow-up the patient was asymptomatic. PMID:10405568

  14. Three-dimensional analysis for radio-frequency ablation of liver tumor with blood perfusion effect.

    PubMed

    Sheu, Tony W H; Chou, C W; Tsai, S F; Liang, P C

    2005-08-01

    Increase of temperature above 50 approximately 60 degrees C for few minutes by the emitted radio-frequency (RF) energy has been shown to be able to denaturate the intracellular proteins and destruct membranes of tumor cells. To improve the efficacy of this thermal therapy, it is important to investigate factors that may affect the RF heating characteristics for the hepatocellular carcinoma and metastatic liver tumors. In order to make sure the applied RF energy is adequate to ablate the target tumor, a 3D thermoelectric analysis for the system consisting of liver, liver arteries and 4 mm diameter tumor is conducted. The effect of blood perfusion is addressed in this study. PMID:16298845

  15. Stellate ganglion pulsed radiofrequency ablation for stretch induced complex regional pain syndrome type II

    PubMed Central

    Singh Rana, Shiv Pratap; Abraham, Mary; Gupta, Varun; Biswas, Shubhashish; Marda, Manish

    2015-01-01

    Complex regional pain syndrome (CRPS) following injury or nerve damage, as its name signifies, is a challenging entity, and its successful management requires a multidisciplinary approach. It not only manifests as severe pain, but also gives rise to functional disability, lack of sleep, lack of enjoyment of life and poor quality of life. Various pain interventional techniques have been described in the literature for the management of CRPS ranging from sympathetic blocks to spinal cord stimulator. A 34-year-old liver transplant donor, who developed position-induced right upper limb neuropathic pain suggestive of CRPS type II was managed initially with medications and later with stellate ganglion block under fluoroscopic guidance at cervical C7 position. Following an initial significant improvement in pain and allodynia, which was transient, a pulsed radiofrequency ablation of stellate ganglion was performed successfully to provide prolonged and sustained pain relief, which persisted up to 14 months of follow-up. PMID:26543471

  16. A study of the sink effect by blood vessels in radiofrequency ablation.

    PubMed

    Zorbas, George; Samaras, Theodoros

    2015-02-01

    The objective of the current work was to study the sink effect in radiofrequency ablation (RFA) caused by a blood vessel located close to an electrode in a two-compartment numerical model, consisting of a spherical tumor embedded in healthy liver tissue. Several blood vessels of different sizes were studied at different distances from the electrode. It was found that when a straight blood vessel, cylindrical in shape, is located parallel to the electrode, the minimum distance for a drop of only 10% in the isothermal treatment volume above 50°C, compared to the model without the blood vessel, varies from 4.49 mm (for a vessel of 2mm in diameter) to 20.02 mm (for a vessel 20mm in diameter). The results can be used as a guideline to clinical practitioners, in order to quickly assess the potential impact of existing blood vessels on the resulting treatment volume. PMID:25575184

  17. Postcardiac injury syndrome following vascular interventional radiofrequency ablation for paroxysmal atrial fibrillation

    PubMed Central

    Yukumi, Shungo; Ichiki, Hiraku; Funada, Junichi; Suzuki, Hideaki; Morimoto, Masamitsu; Fujita, Teppei; Izumi, Naoki; Abe, Masahiro

    2015-01-01

    Postcardiac injury syndrome (PCIS) occurs following a pericardial or myocardial injury. On the other hand, PCIS following cardiac catheter intervention is rare and can be difficult to diagnose because of its delayed onset. A 24-year-old man underwent radiofrequency ablation (RFA) for paroxysmal atrial fibrillation and suffered from general fatigue and left-sided pleural effusion three months after the procedure. His symptoms and effusion were effectively treated within a month by administrating nonsteroidal anti-inflammatory drugs. However, seven months later, he developed left-sided chest pain and low-grade fever. Computed tomography showed a thickening of the parietal pleura and reccurence of the pleural effusion. Pleural biopsy by video-assisted thoracoscopy demonstrated chronic pleuritis with a non-necrotizing granulomatous reaction. Given the previous RFA, and in the absence of infection or malignant disease, he was diagnosed with PCIS and treated with colchicine. PMID:26236613

  18. Radiofrequency ablation-combined multimodel therapies for hepatocellular carcinoma: Current status.

    PubMed

    Chen, Lumin; Sun, Jihong; Yang, Xiaoming

    2016-01-01

    Radiofrequency ablation (RFA) is widely accepted as a first-line interventional oncology approach for hepatocellular carcinoma (HCC) and has the advantages of high treatment efficacy and low complication risk. Local control rates equivalent to hepatic resection can be reached by RFA alone when treating small HCCs (<2 cm) in favorable locations. However, local tumor progression and recurrence rates with RFA monotherapy increase sharply when treating larger lesions (>3 cm). To address this clinical problem, recent efforts have focused on multimodel management of HCC by combining RFA with different techniques, including percutaneous ethanol injection, transarterial chemo-embolization, targeted molecular therapy, nanoparticle-mediated therapy, and immunotherapy. The combination strategy indeed leads to better outcomes in comparison to RFA alone. In this article, we review the current status of RFA-combined multimodal therapies in the management of HCC. PMID:26472630

  19. Sacroiliac joint radiofrequency ablation with a multilesion probe: a case series of 60 patients.

    PubMed

    Schmidt, Peter C; Pino, Carlos A; Vorenkamp, Kevin E

    2014-08-01

    This retrospective case series of patients with refractory sacroiliac joint (SIJ) pain presents our first 77 SIJ radiofrequency ablation (RFA) procedures performed with a multilesion probe. Of these, 16 (20.8%) provided no relief; 55 (71.4%) provided >50% pain relief at 6 weeks; 42 (54.5%, 95% confidence interval, 42.8%-65.8%) provided >50% pain relief at 6 months; and 12 (15.6%) continued to provide >50% pain relief at 1 year. These results compare favorably to those published using other RFA techniques. In conclusion, more than half of our patients with refractory SIJ pain received some pain relief for at least 6 months after RFA. PMID:25046790

  20. Quantification of the effect of electrical and thermal parameters on radiofrequency ablation for concentric tumour model of different sizes.

    PubMed

    Jamil, Muhammad; Ng, E Y K

    2015-07-01

    Radiofrequency ablation (RFA) has been increasingly used in treating cancer for multitude of situations in various tissue types. To perform the therapy safely and reliably, the effect of critical parameters needs to be known beforehand. Temperature plays an important role in the outcome of the therapy and any uncertainties in temperature assessment can be lethal. This study presents the RFA case of fixed tip temperature where we've analysed the effect of electrical conductivity, thermal conductivity and blood perfusion rate of the tumour and surrounding normal tissue on the radiofrequency ablation. Ablation volume was chosen as the characteristic to be optimised and temperature control was achieved via PID controller. The effect of all 6 parameters each having 3 levels was quantified with minimum number of experiments harnessing the fractional factorial characteristic of Taguchi's orthogonal arrays. It was observed that as the blood perfusion increases the ablation volume decreases. Increasing electrical conductivity of the tumour results in increase of ablation volume whereas increase in normal tissue conductivity tends to decrease the ablation volume and vice versa. Likewise, increasing thermal conductivity of the tumour results in enhanced ablation volume whereas an increase in thermal conductivity of the surrounding normal tissue has a debilitating effect on the ablation volume and vice versa. With increase in the size of the tumour (i.e., 2-3cm) the effect of each parameter is not linear. The parameter effect varies with change in size of the tumour that is manifested by the different gradient observed in ablation volume. Most important is the relative insensitivity of ablation volume to blood perfusion rate for smaller tumour size (2cm) that is also in accordance with the previous results presented in literature. These findings will provide initial insight for safe, reliable and improved treatment planning perceptively. PMID:25965014

  1. Hepatocellular Carcinoma within Milan Criteria: No-Touch Multibipolar Radiofrequency Ablation for Treatment-Long-term Results.

    PubMed

    Seror, Olivier; N'Kontchou, Gisèle; Nault, Jean-Charles; Rabahi, Yacine; Nahon, Pierre; Ganne-Carrié, Nathalie; Grando, Véronique; Zentar, Nora; Beaugrand, Michel; Trinchet, Jean-Claude; Diallo, Abou; Sellier, Nicolas

    2016-08-01

    Purpose To assess the long-term outcome in 108 consecutive patients treated with no-touch multibipolar radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) that met the Milan criteria. Materials and Methods This retrospective study was approved by the ethical review board, and the need to obtain informed consent was waived. Between November 1, 2006, and December 31, 2011, 132 HCC tumors (diameter, 10-45 mm; 39 tumors ≥ 30 mm) in 108 consecutive patients (106 with cirrhosis) that met Milan criteria were treated with no-touch multibipolar RFA, which consisted of activating, in bipolar mode, three or four electrodes inserted just beyond the tumor margins. Follow-up was performed every 3 months for 2 years and every 6 months thereafter with computed tomographic or magnetic resonance imaging. Survival probabilities were computed by using the Kaplan-Meier method. Predictive factors of tumor progression and overall survival were assessed by using the Cox proportional hazard model. Results No technical failure occurred, and complete ablation was achieved for all the nodules. After a median of 40.5 months (range, 2-84 months) of follow-up, 3- and 5-year local and overall tumor progression-free survival were 96%, 94%, 52%, and 32%, respectively. Neither tumor diameter greater than 30 mm nor location abutting a large vessel were associated with local tumor progression. Tumor diameter greater than 30 mm was the only parameter predictive of overall tumor progression (P = .0036). Independent factors associated with shorter overall survival were Child-Pugh class B disease, age greater than 65 years, and platelet count of less than 150 g/L (P < .003). Three major complications occurred (2.7%): hemothorax in one patient and liver failure in two, with major portal-systemic shunts. One patient (0.9%) died, and one underwent transplantation. Conclusion No-touch multibipolar RFA for HCC tumors that meet Milan criteria provides a high local tumor progression-free survival

  2. Clinical evaluation of the efficacy and safety of fractional bipolar radiofrequency for the treatment of moderate to severe acne scars.

    PubMed

    Verner, Ines

    2016-01-01

    Several treatment modalities are used for the treatment of acne scars with variable results. Recent studies showed that fractional radiofrequency may be an effective treatment modality for acne scars. The objective of this study was to assess the efficacy, safety, tolerability and patient satisfaction of fractional bipolar radiofrequency (RF), the eTwo™ system (Syneron Candela Ltd., Yokneam, Israel) for treating acne scars. Twelve patients with moderate to severe acne scars received 3-5 treatments with the Sublative fractionated bipolar RF applicator of the eTwo device at 1-month intervals. Patients were evaluated clinically and photographically at each visit and 3 months after the final treatment. Very good improvement (at least one scale) was seen after completing the five treatments. The patient satisfaction survey (Global Aesthetic Improvement Scale scores) revealed that half (6 out of 12) of the patients reported to be satisfied with treatment results, while the other half reported to be very satisfied. Beyond the expected erythema and minimal scab formation in the treated areas, which was mild and transient, none of the participants reported any adverse events. The data presented here support the high efficacy and safety of fractionated bipolar RF for the aesthetic improvement of moderate to severe acne scars. PMID:26279170

  3. Radiofrequency interstitial tumor ablation (RITA) is a possible new modality for treatment of renal cancer: ex vivo and in vivo experience.

    PubMed

    Zlotta, A R; Wildschutz, T; Raviv, G; Peny, M O; van Gansbeke, D; Noel, J C; Schulman, C C

    1997-08-01

    Small renal tumors are increasingly diagnosed and are frequently treated by nephron-sparing surgery. Tumors can be ablated by radiofrequency (RF) energy, which allows the operator to create very localized necrotic lesions. Radiofrequency interstitial tumor ablation (RITA) has been used in human kidneys in an ex vivo experiment to assess the necrotic lesions produced in a model close to physiologic conditions and then in three patients with localized renal cancer prior to radical nephrectomy. In the ex vivo model, four freshly removed kidneys were treated. Bipolar RF energy was delivered by a generator connected to two needles introduced parallel to each other into the renal parenchyma. A thermocouple was inserted between the two active electrodes. The renal artery at physiologic conditions was maintained at a constant temperature of perfusion of 37 degrees C by a computer-assisted Hot-line monitor. Two lesions were produced in each pole of each kidney including the cortex and the medulla. In an initial human study focusing on safety, feasibility, and pathology, three patients were treated by RITA with bipolar and monopolar energy. One patient with a peripheral 2-cm upper-pole tumor was treated percutaneously under ultrasound guidance with local anesthesia only 1 week prior to surgery. The other patients, with 3- and 5-cm tumors, were treated during surgery under general anesthesia just before nephrectomy. Ex vivo, the maximum temperature at the active needles ranged from 84 degrees C to 130 degrees C with 10 to 14 W applied during 10 to 14 minutes. Lesions were on average 2.2 x 3 x 2.5 cm.3 Microscopic examination showed stromal edema with intensive pyknosis. No damage was seen to adjacent untreated tissue. In the in vivo procedure, tolerance of RTA as an anesthesia-free procedure was excellent. The size of the observed lesions was comparable to the forecast size depending on the needle deployment. No side effects were noted, and no adjacent structures were

  4. Ultrasound elastographic imaging of thermal lesions and temperature profiles during radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Techavipoo, Udomchai

    Manual palpation to sense variations in tissue stiffness for disease diagnosis has been regularly performed by clinicians for centuries. However, it is generally limited to large and superficial structures and the ability of the physician performing the palpation. Imaging of tissue stiffness or elastic properties via the aid of modern imaging such as ultrasound and magnetic resonance imaging, referred to as elastography, enhances the capability for disease diagnosis. In addition, elastography could be used for monitoring tissue response to minimally invasive ablative therapies, which are performed percutaneously to destruct tumors with minimum damage to surrounding tissue. Monitoring tissue temperature during ablation is another approach to estimate tissue damage. The ultimate goal of this dissertation is to improve the image quality of elastograms and temperature profiles for visualizing thermal lesions during and after ablative therapies. Elastographic imaging of thermal lesions is evaluated by comparison of sizes, shapes, and volumes with the results obtained using gross pathology. Semiautomated segmentation of lesion boundaries on elastograms is also developed. It provides comparable results to those with manual segmentation. Elastograms imaged during radiofrequency ablation in vitro show that the impact of gas bubbles during ablation on the ability to delineate the thermal lesion is small. Two novel methods to reduce noise artifacts in elastograms, and an accurate estimation of displacement vectors are proposed. The first method applies wavelet-denoising algorithms to the displacement estimates. The second method utilizes angular compounding of the elastograms generated using ultrasound signal frames acquired from different insonification angles. These angular frames are also utilized to estimate all tissue displacement vector components in response to a deformation. These enable the generation of normal and shear strain elastograms and Poisson's ratio

  5. Lumped Element Electrical Model based on Three Resistors for Electrical Impedance in Radiofrequency Cardiac Ablation: Estimations from Analytical Calculations and Clinical Data

    PubMed Central

    Berjano, Enrique; d'Avila, Andre

    2013-01-01

    The electrical impedance measured during radiofrequency cardiac ablation (RFCA) is widely used in clinical studies to predict the heating evolution and hence the success of the procedure. We hypothesized that a model based on three resistors in series can mimic the total electrical impedance measured during RFCA. The three resistors or impedances are given by: impedance associated with the tissue around the active electrode (myocardium and circulating blood) (Z-A), that associated with the tissue around the dispersive electrode (Z-DE) and that associated with the rest of the body (Z-B). Our objective was to quantify the values associated with these three impedance types by an analytical method, after which the values obtained would be compared to those estimated from clinical data from previous studies. The results suggest that an RFCA using a 7 Fr 4-mm electrode would give a Z-A of around 75 ohms, a Z-DE around 20 ohms, and Z-B would be 15±10 ohms (for body surface area variations between 1.5 and 2.5 m^2). Finally, adaptations of the proposed model were used to explain the results of previous clinical studies using a different electrode arrangement, such as in bipolar ablation of the ventricular septum. PMID:23961299

  6. Numerical study of the influence of water evaporation on radiofrequency ablation

    PubMed Central

    2013-01-01

    Background Radiofrequency ablation is a promising minimal invasive treatment for tumor. However, water loss due to evaporation has been a major issue blocking further RF energy transmission and correspondently eliminating the therapeutic outcome of the treatment. Method A 2D symmetric cylindrical mathematical model coupling the transport of the electrical current, heat, and the evaporation process in the tissue, has been developed to simulate the treatment process and investigate the influence of the excessive evaporation of the water on the treatment. Results Our results show that the largest specific absorption rate (Q SAR ) occurs at the edge of the circular surface of the electrode. When excessive evaporation takes place, the water dehydration rate in this region is the highest, and after a certain time, the dehydrated tissue blocks the electrical energy transmission in the radial direction. It is found that there is an interval as long as 65 s between the beginning of the evaporation and the increase of the tissue impedance. The model is further used to investigate whether purposely terminating the treatment for a while allowing diffusion of the liquid water into the evaporated region would help. Results show it has no obvious improvement enlarging the treatment volume. Treatment with the cooled-tip electrode is also studied. It is found that the cooling conditions of the inside agent greatly affect the water loss pattern. When the convection coefficient of the cooling agent increases, excessive evaporation will start from near the central axis of the tissue cylinder instead of the edge of the electrode, and the coagulation volume obviously enlarges before a sudden increase of the impedance. It is also found that a higher convection coefficient will extend the treatment time. Though the sudden increase of the tissue impedance could be delayed by a larger convection coefficient; the rate of the impedance increase is also more dramatic compared to the case with

  7. Imaging the spectral reflectance properties of bipolar radiofrequency-fused bowel tissue

    NASA Astrophysics Data System (ADS)

    Clancy, Neil T.; Arya, Shobhit; Stoyanov, Danail; Du, Xiaofei; Hanna, George B.; Elson, Daniel S.

    2015-07-01

    Delivery of radiofrequency (RF) electrical energy is used during surgery to heat and seal tissue, such as vessels, allowing resection without blood loss. Recent work has suggested that this approach may be extended to allow surgical attachment of larger tissue segments for applications such as bowel anastomosis. In a large series of porcine surgical procedures bipolar RF energy was used to resect and re-seal the small bowel in vivo with a commercial tissue fusion device (Ligasure; Covidien PLC, USA). The tissue was then imaged with a multispectral imaging laparoscope to obtain a spectral datacube comprising both fused and healthy tissue. Maps of blood volume, oxygen saturation and scattering power were derived from the measured reflectance spectra using an optimised light-tissue interaction model. A 60% increase in reflectance of visible light (460-700 nm) was observed after fusion, with the tissue taking on a white appearance. Despite this the distinctive shape of the haemoglobin absorption spectrum was still noticeable in the 460-600 nm wavelength range. Scattering power increased in the fused region in comparison to normal serosa, while blood volume and oxygen saturation decreased. Observed fusion-induced changes in the reflectance spectrum are consistent with the biophysical changes induced through tissue denaturation and increased collagen cross-linking. The multispectral imager allows mapping of the spatial extent of these changes and classification of the zone of damaged tissue. Further analysis of the spectral data in parallel with histopathological examination of excised specimens will allow correlation of the optical property changes with microscopic alterations in tissue structure.

  8. Acoustic radiation force impulse elastography for hepatocellular carcinoma-associated radiofrequency ablation

    PubMed Central

    Kwon, Hee-Jin; Kang, Myong-Jin; Cho, Jin-Han; Oh, Jong-Young; Nam, Kyung-Jin; Han, Sang-Yeong; Lee, Sung Wook

    2011-01-01

    AIM: To evaluate the potential usefulness of acoustic radiation force impulse (ARFI) images for evaluation of hepatocellular carcinomas (HCC)-associated radiofrequency ablation. METHODS: From January 2010 to June 2010, a total of 38 patients with HCC including recurred HCCs after RFA underwent ARFI elastography. The brightness of tumor was checked and the shear wave velocity was measured for the quantification of stiffness. According to the brightness, the tumors were classified as brighter, same color and darker compared with adjacent parenchyma. Using the same methods, 8 patients with recurred HCCs after RFA state were evaluated about the brightness compared with adjacent RFA ablation area. RESULTS: In the 38 patients with HCCs, 20 (52.6%) were brighter than surrounding cirrhotic parenchyma. Another 13 (34.2%) were darker. The others (5 cases, 13.2%) were seen as the same color as the adjacent liver parenchyma. Post-RFA lesions were darker than previous tumor and surrounding parenchyma in all 38 cases. However, recurred HCCs were brighter than the treated site in all 8 cases. CONCLUSION: Using ARFI technique is helpful for differential diagnosis in order to detect recurred HCCs more easily in patients with confusing status. PMID:21528062

  9. Cell death, perfusion and electrical parameters are critical in models of hepatic radiofrequency ablation

    PubMed Central

    Hall, Sheldon K.; Ooi, Ean H.; Payne, Stephen J.

    2015-01-01

    Abstract Purpose: A sensitivity analysis has been performed on a mathematical model of radiofrequency ablation (RFA) in the liver. The purpose of this is to identify the most important parameters in the model, defined as those that produce the largest changes in the prediction. This is important in understanding the role of uncertainty and when comparing the model predictions to experimental data. Materials and methods: The Morris method was chosen to perform the sensitivity analysis because it is ideal for models with many parameters or that take a significant length of time to obtain solutions. A comprehensive literature review was performed to obtain ranges over which the model parameters are expected to vary, crucial input information. Results: The most important parameters in predicting the ablation zone size in our model of RFA are those representing the blood perfusion, electrical conductivity and the cell death model. The size of the 50 °C isotherm is sensitive to the electrical properties of tissue while the heat source is active, and to the thermal parameters during cooling. Conclusions: The parameter ranges chosen for the sensitivity analysis are believed to represent all that is currently known about their values in combination. The Morris method is able to compute global parameter sensitivities taking into account the interaction of all parameters, something that has not been done before. Research is needed to better understand the uncertainties in the cell death, electrical conductivity and perfusion models, but the other parameters are only of second order, providing a significant simplification. PMID:26000972

  10. Patient-specific left atrial wall-thickness measurement and visualization for radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Inoue, Jiro; Skanes, Allan C.; White, James A.; Rajchl, Martin; Drangova, Maria

    2014-03-01

    INTRODUCTION: For radiofrequency (RF) catheter ablation of the left atrium, safe and effective dosing of RF energy requires transmural left atrium ablation without injury to extra-cardiac structures. The thickness of the left atrial wall may be a key parameter in determining the appropriate amount of energy to deliver. While left atrial wall-thickness is known to exhibit inter- and intra-patient variation, this is not taken into account in the current clinical workflow. Our goal is to develop a tool for presenting patient-specific left atrial thickness information to the clinician in order to assist in the determination of the proper RF energy dose. METHODS: We use an interactive segmentation method with manual correction to segment the left atrial blood pool and heart wall from contrast-enhanced cardiac CT images. We then create a mesh from the segmented blood pool and determine the wall thickness, on a per-vertex basis, orthogonal to the mesh surface. The thickness measurement is visualized by assigning colors to the vertices of the blood pool mesh. We applied our method to 5 contrast-enhanced cardiac CT images. RESULTS: Left atrial wall-thickness measurements were generally consistent with published thickness ranges. Variations were found to exist between patients, and between regions within each patient. CONCLUSION: It is possible to visually determine areas of thick vs. thin heart wall with high resolution in a patient-specific manner.

  11. Management of Renal Tumors by Image-Guided Radiofrequency Ablation: Experience in 105 Tumors

    SciTech Connect

    Breen, David J. Rutherford, Elizabeth E.; Stedman, Brian; Roy-Choudhury, Shuvro H.; Cast, James E. I.; Hayes, Matthew C.; Smart, Christopher J.

    2007-09-15

    Aims. In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors. Materials and Methods. RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11-68 mm). The mean patient age was 71.7 years (range, 36-89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome. Results. Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson {chi}{sup 2}) Five patients had complications. There have been no local recurrences. Conclusion. Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors.

  12. Reversible cardiomyopathy after radiofrequency ablation of 30-year persistent atrial tachycardia

    PubMed Central

    Suzuki, Atsushi; Shiga, Tsuyoshi; Arai, Kotaro; Shoda, Morio

    2013-01-01

    Tachycardia-induced cardiomyopathy (TIC) is a reversible form of the left ventricular (LV) systolic dysfunction and is believed to be a relatively acute process. We report a TIC case with a 30-year history of long-lasting persistent atrial tachycardia involving a 44-year-old man previously diagnosed with dilated cardiomyopathy and a low LV ejection fraction (LVEF) of 20%. ECG revealed atrial tachycardia at 110–120 bpm. He was hospitalised with a worsening heart failure. His clinical status was New York Heart Association functional class III, and echocardiography revealed LV dilation and an LVEF of 9%. A two-dimensional speckle-tracking strain measurement revealed LV mechanical dyssynchrony. He underwent radiofrequency ablation for atrial tachycardia. After restoring sinus rhythm, his cardiac symptoms improved immediately. The LV mechanical dyssynchrony decreased a week after ablation, without changes in the LV dilation or LVEF. Thereafter, the LV dilation and systolic function gradually improved, and atrial tachycardia and heart failure remained absent. PMID:24326427

  13. Pulmonary vein stenosis complicating radiofrequency catheter ablation for atrial fibrillation: A literature review.

    PubMed

    Edriss, Hawa; Denega, Tatiana; Test, Victor; Nugent, Kenneth

    2016-08-01

    Radiofrequency catheter ablation has become a widely used intervention in the treatment of atrial fibrillation. Pulmonary vein stenosis (PVS) is one of the most serious complications associated with this procedure; the degree of stenosis ranges from mild (<50%) to complete venous occlusion. The natural history of PVS and the risk of progression of existing PVS are uncertain. Symptomatic and/or severe PVS is a serious medical problem and can be easily misdiagnosed since it is an uncommon and relatively new medical problem, often has low clinical suspicion among clinicians, and has a non-specific presentation that mimics other more common respiratory or cardiac diseases. The estimated incidence varies in literature reports from 0% to 42% of ablation procedures, depending on technical aspects of the procedure and operator skill. Most patients with significant PVS remain asymptomatic or have few symptoms. Symptomatic patients usually present with dyspnea, chest pain, or hemoptysis and are usually treated with balloon angioplasty and/or stent placement. Little is known about the long term effect of PV stenosis/occlusion on the pulmonary circulation and the development of pulmonary hypertension. Evolving technology may reduce the frequency of this complication, but long term studies are needed to understand the effect of therapeutic atrial injury and adverse outcomes. This review summarizes the current literature and outlines an approach to the evaluation and management of these patients. PMID:27492534

  14. Radiofrequency ablation of the pancreas: protective effect of local cooling techniques.

    PubMed

    Geranios, Angelos; Pikoulis, Emmanouil; Papalois, Apostolos; Kontos, Michael; Agrogiannis, George; Petrou, Athanasios; Pavlakis, Emmanuel; Felekouras, Evangelos

    2015-05-01

    Pancreatic carcinoma is one of the commonest malignant diseases today and the majority of patients are suitable for palliative treatment only. Radiofrequency ablation (RFA) has been used extensively for the treatment of solid organ tumors but little is known on the efficacy and safety of pancreatic ablation. To further investigate the safety of pancreatic RFA, 18 pigs had RFA of the pancreas, close to superior mesenteric vein and duodenum. Group A (nine animals) was protected with peripancreatic cool perfusion and Group B (nine animals) with portal vein (PV) intravenous injection of cool saline. Biochemical and histological evidence suggested lateral thermal injury of the duodenal wall and superior mesenteric vein and acute pancreatitis in most animals. However, clinically and at autopsy, Group B animals fared much better. PV thrombosis, hepatic abscess, duodenal perforation, ascites, and extensive pancreatic necrosis were observed in Group A but not in Group B. The present study suggests that PV cool saline perfusion can prevent major complications caused by pancreatic RFA and may be used in combination with other protective techniques in the clinical setting to reduce RFA-associated morbidity. PMID:25975333

  15. Automatic alignment of pre- and post-interventional liver CT images for assessment of radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Rieder, Christian; Wirtz, Stefan; Strehlow, Jan; Zidowitz, Stephan; Bruners, Philipp; Isfort, Peter; Mahnken, Andreas H.; Peitgen, Heinz-Otto

    2012-02-01

    Image-guided radiofrequency ablation (RFA) is becoming a standard procedure for minimally invasive tumor treatment in clinical practice. To verify the treatment success of the therapy, reliable post-interventional assessment of the ablation zone (coagulation) is essential. Typically, pre- and post-interventional CT images have to be aligned to compare the shape, size, and position of tumor and coagulation zone. In this work, we present an automatic workflow for masking liver tissue, enabling a rigid registration algorithm to perform at least as accurate as experienced medical experts. To minimize the effect of global liver deformations, the registration is computed in a local region of interest around the pre-interventional lesion and post-interventional coagulation necrosis. A registration mask excluding lesions and neighboring organs is calculated to prevent the registration algorithm from matching both lesion shapes instead of the surrounding liver anatomy. As an initial registration step, the centers of gravity from both lesions are aligned automatically. The subsequent rigid registration method is based on the Local Cross Correlation (LCC) similarity measure and Newton-type optimization. To assess the accuracy of our method, 41 RFA cases are registered and compared with the manually aligned cases from four medical experts. Furthermore, the registration results are compared with ground truth transformations based on averaged anatomical landmark pairs. In the evaluation, we show that our method allows to automatic alignment of the data sets with equal accuracy as medical experts, but requiring significancy less time consumption and variability.

  16. 27.12 MHz Radiofrequency Ablation for Benign Cutaneous Lesions

    PubMed Central

    Kim, Dong Hyun; Hyun, Dong Ju; Piquette, Raymonde; Beaumont, Clément; Germain, Lucie; Larouche, Danielle

    2016-01-01

    As surgical and/or ablative modalities, radiofrequency (RF) has been known to produce good clinical outcomes in dermatology. Recently, 27.12 MHz RF has been introduced and has several advantages over conventional 4 or 6 MHz in terms of the precise ablation and lesser pain perception. We aimed to evaluate the clinical efficacy and safety of 27.12 MHz RF for the treatment of benign cutaneous lesions. Twenty female patient subjects were enrolled. Digital photography and a USB microscope camera were used to monitor the clinical results before one session of treatment with 27.12 MHz RF and after 1 and 3 weeks. Treated lesions included telangiectasias, cherry and spider angiomas, skin tags, seborrheic keratoses, lentigo, milium, dilated pore, acne, piercing hole, and one case of neurofibroma. For vascular lesions, clinical results were excellent for 33.3%, good for 44.4%, moderate for 11.1%, and poor for 11.1%. For nonvascular lesions (epidermal lesions and other benign cutaneous lesions), clinical results were excellent for 48.3%, good for 45.2%, moderate for 3.2%, and poor for 3.2%. No serious adverse events were observed. Mild adverse events reported were slight erythema, scale, and crust. The 27.12 MHz RF treatment of benign vascular and nonvascular lesions appears safe and effective after 3 weeks of follow-up. PMID:27127789

  17. Radiofrequency Ablation of Liver Metastases from Colorectal Cancer: A Literature Review

    PubMed Central

    Kudo, Masatoshi

    2013-01-01

    Liver metastases occur in up to 60% of patients with colorectal cancer, and the control of liver metastases is considered to be of primary importance because it is a critical factor in determining prognosis. Radiofrequency ablation (RFA) therapy is one of the least invasive techniques for unresectable hepatic malignancies and can be performed safely using percutaneous, laparoscopic, or open surgical techniques. The local tumor progression rates after RFA for colorectal liver metastases range from 8.8% to 40.0%, and 5-year survival rates range from 20.0% to 48.5%. No prospective, randomized trials comparing the efficacy of RFA with that of surgical resection for colorectal liver metastases are currently available. However, some retrospective studies have reported that patients who received RFA had a survival rate similar to that observed in surgically treated groups, while other studies have reported better survival among patients who underwent surgical resection. The use of a laparoscopic or open surgical approach allows the repeated placement of RFA electrodes at multiple sites to ablate larger tumors. An accurate evaluation of treatment response is very important for the success of RFA therapy because a sufficient safety margin (at least 0.5 cm) can prevent local tumor progression. This review critically summarizes the current status of RFA for liver metastases from colorectal cancer. PMID:23422905

  18. Prevention of Biliary Lesions That May Occur During Radiofrequency Ablation of the Liver

    PubMed Central

    Marchal, Frédéric; Elias, Dominique; Rauch, Philippe; Zarnegar, Rasa; Leroux, Agnès; Stines, Joseph; Verhaeghe, Jean-Luc; Guillemin, François; Carteaux, Jean Pierre; Villemot, Jean Pierre

    2006-01-01

    Objective: To prevent bile duct injury by using a cold 5% glucose isotonic solution cooling in the bile ducts when radiofrequency (RF) is performed in a porcine model. Summary Background Data: Complications that may arise during liver RF ablation include biliary stenosis and abscesses. Methods: The RITA 1500 generator was used for the experiments. Two lesions were performed in the left liver. The pigs were killed 1 or 3 weeks after the procedure. An ex vivo cholangiogram was obtained by direct injection into the main bile duct. Samples of RF lesions, of liver parenchyma near and at a distance from the RF lesions, underwent pathologic studies. Two groups of 20 pigs each were treated: one without perfusion of the bile ducts and the other with perfusion of cold 5% glucose isotonic solution into the bile ducts. The Pringle maneuver was used in 50% of the RF procedures. Radiologic lesions were classified as biliary stenosis, complete interruption of the bile duct, or extravasation of the radiologic contrast liquid. Results: Histologic lesions of the bile ducts were observed near the ablated RF lesion site and at a distance from the RF lesions when a Pringle maneuver was performed. Radiologic and histologic lesions of the bile ducts were significantly reduced (P < 0.0001) when the bile ducts were cooled. Conclusions: Cooling of the bile ducts with a cold 5% glucose isotonic solution significantly protects the intrahepatic bile ducts from damages caused by the heat generated by RF when performed close to the bile ducts. PMID:16371740

  19. Dynamic frame selection for in vivo ultrasound temperature estimation during radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Daniels, Matthew J.; Varghese, Tomy

    2010-08-01

    Minimally invasive therapies such as radiofrequency ablation have been developed to treat cancers of the liver, prostate and kidney without invasive surgery. Prior work has demonstrated that ultrasound echo shifts due to temperature changes can be utilized to track the temperature distribution in real time. In this paper, a motion compensation algorithm is evaluated to reduce the impact of cardiac and respiratory motion on ultrasound-based temperature tracking methods. The algorithm dynamically selects the next suitable frame given a start frame (selected during the exhale or expiration phase where extraneous motion is reduced), enabling optimization of the computational time in addition to reducing displacement noise artifacts incurred with the estimation of smaller frame-to-frame displacements at the full frame rate. A region of interest that does not undergo ablation is selected in the first frame and the algorithm searches through subsequent frames to find a similarly located region of interest in subsequent frames, with a high value of the mean normalized cross-correlation coefficient value. In conjunction with dynamic frame selection, two different two-dimensional displacement estimation algorithms namely a block matching and multilevel cross-correlation are compared. The multi-level cross-correlation method incorporates tracking of the lateral tissue expansion in addition to the axial deformation to improve the estimation performance. Our results demonstrate the ability of the proposed motion compensation using dynamic frame selection in conjunction with the two-dimensional multilevel cross-correlation to track the temperature distribution.

  20. MRI-based finite element simulation on radiofrequency ablation of thyroid cancer.

    PubMed

    Jin, Chao; He, Zhizhu; Liu, Jing

    2014-02-01

    In order to provide a quantitative disclosure on the RFA (radiofrequency ablation)-induced thermal ablation effects within thyroid tissues, this paper has developed a three-dimensional finite element simulation strategy based on a MRI (magnetic resonance imaging)-reconstructed model. The thermal lesion's growth was predicted and interpreted under two treatment conditions, i.e. single-cooled-electrode modality and two-cooled-electrode system. The results show that the thermal lesion's growth is significantly affected by two factors including the position of RF electrode and thermal-physiological behavior of the breathing airflow. Additional parametric studies revealed several valuable phenomena, e.g. with the electrode's movement, thermal injury with varying severity would happen to the trachea wall. Besides, the changes in airflow mass produced evident effects on the total heat flux of thyroid surface, while the changes in breathing frequency only generated minor effects that can be ignored. The present study provided a better understanding on the thermal lesions of RFA within thyroid domain, which will help guide future treatment of the thyroid cancer. PMID:24411316

  1. Radiofrequency ablation of the great saphenous vein in an elderly patient with co-morbid disease.

    PubMed

    Yener, Alı Ümıt; Yener, Özlem; Gedik, Hikmet Selçuk; Korkmaz, Kemal; Özkan, Turgut; Lafçi, Ayşe; Çağli, Kerim

    2013-08-01

    An 86-year-old male patient with hypertension, Parkinsonism, benign prostatic hyperplasia, cataract and chronic obstructive pulmonary disease had a history of coronary bypass surgery in two veins due to anterior myocardial infarction one year earlier. He presented with pain and feelings of paresthesia below the knee of his left leg, and had fallen twice. He had used compressions and venoprotective medication for two years and had also received physiotherapy but it had not alleviated the symptoms. He had varicose dilatations in the left leg and pigmentation and a recovered venous ulcer scar were present on the medial malleolus. The patient was classed as grade 4 according to the CEAP classification. Because there was no deficiency in the superficial femoral and popliteal veins, the patient was taken for endovenous ablation. He had no pain or sensation of heaviness in the legs on postoperative day 10, and the first, third and sixth months of check up. Endovenous ablation is a procedure that increases the quality of life and comfort in elderly patients, with minimal pain. Radiofrequency catheter procedures have proven to be more successful in patients of all age groups than procedures such as standard surgery and foam therapy. PMID:24217337

  2. Radiofrequency ablation in primary non-small cell lung cancer: What a radiologist needs to know

    PubMed Central

    Bhatia, Shivank; Pereira, Keith; Mohan, Prasoon; Narayanan, Govindarajan; Wangpaichitr, Medhi; Savaraj, Niramol

    2016-01-01

    Lung cancer continues to be one of the leading causes of death worldwide. In advanced cases of lung cancer, a multimodality approach is often applied, however with poor local control rates. In early non-small cell lung cancer (NSCLC), surgery is the standard of care. Only 15-30% of patients are eligible for surgical resection. Improvements in imaging and treatment delivery systems have provided new tools to better target these tumors. Stereotactic body radiation therapy (SBRT) has evolved as the next best option. The role of radiofrequency ablation (RFA) is also growing. Currently, it is a third-line option in stage 1 NSCLC, when SBRT cannot be performed. More recent studies have demonstrated usefulness in recurrent tumors and some authors have also suggested combination of RFA with other modalities in larger tumors. Following the National Lung Screening Trial (NLST), screening by low-dose computed tomography (CT) has demonstrated high rates of early-stage lung cancer detection in high-risk populations. Hence, even considering the current role of RFA as a third-line option, in view of increasing numbers of occurrences detected, the number of potential RFA candidates may see a steep uptrend. In view of all this, it is imperative that interventional radiologists be familiar with the techniques of lung ablation. The aim of this article is to discuss the procedural technique of RFA in the lung and review the current evidence regarding RFA for NSCLC. PMID:27081229

  3. Radiation exposure to operator and patients during cardiac electrophysiology study, radiofrequency catheter ablation and cardiac device implantation procedures

    NASA Astrophysics Data System (ADS)

    Lee, C. H.; Cho, J. H.; Park, S. J.; Kim, J. S.; On, Y. K.; Huh, J.

    2015-10-01

    The purpose of this study was to measure the radiation exposure to operator and patient during cardiac electrophysiology study, radiofrequency catheter ablation and cardiac device implantation procedures and to calculate the allowable number of cases per year. We carried out 9 electrophysiology studies, 40 radiofrequency catheter ablation and 11 cardiac device implantation procedures. To measure occupational radiation dose and dose-area product (DAP), 13 photoluminescence glass dosimeters were placed at eyes (inside and outside lead glass), thyroids (inside and outside thyroid collar), chest (inside and outside lead apron), wrists, genital of the operator (inside lead apron), and 6 of photoluminescence glass dosimeters were placed at eyes, thyroids, chest and genital of the patient. Exposure time and DAP values were 11.7 ± 11.8 min and 23.2 ± 26.2 Gy cm2 for electrophysiology study; 36.5 ± 42.1 min and 822.4 ± 125.5 Gy cm2 for radiofrequency catheter ablation; 16.2 ± 9.3 min and 27.8 ± 16.5 Gy cm2 for cardiac device implantation procedure, prospectively. 4591 electrophysiology studies can be conducted within the occupational exposure limit for the eyes (150 mSv), and 658-electrophysiology studies with radiofrequency catheter ablation can be carried out within the occupational exposure limit for the hands (500 mSv). 1654 cardiac device implantation procedure can be conducted within the occupational exposure limit for the eyes (150 mSv). The amounts of the operator and patient's radiation exposure were comparatively small. So, electrophysiology study, radio frequency catheter ablation and cardiac device implantation procedures are safe when performed with modern equipment and optimized protective radiation protect equipment.

  4. Tageted bipolar radiofrequency decompression with vertebroplasty for intractable radicular pain due to spinal metastasis: a case report

    PubMed Central

    Baek, Seong Jin; Lee, Eun Young

    2016-01-01

    Metastatic spinal tumors are usually quite difficult to treat. In patients with metastatic spinal tumors, conventional radiotherapy fails to relieve pain in 20–30% of cases and open surgery often causes considerable trauma and complications, which delays treatment of the primary disease. Percutaneous vertebroplasty (PVP) is considered to be useful in achieving rapid pain control and preventing further vertebral collapse due to spinal metastasis. However, symptoms of intraspinal neural compression can be contraindications to PVP. To overcome this problem, we performed PVP following targeted bipolar radiofrequency decompression, and examined the effect of the combined treatment in relieving severe radicular pain related to spinal cord compression caused by malignant metastatic tumors. PMID:27482319

  5. Tageted bipolar radiofrequency decompression with vertebroplasty for intractable radicular pain due to spinal metastasis: a case report.

    PubMed

    Baek, Seong Jin; Park, Hahck Soo; Lee, Eun Young

    2016-08-01

    Metastatic spinal tumors are usually quite difficult to treat. In patients with metastatic spinal tumors, conventional radiotherapy fails to relieve pain in 20-30% of cases and open surgery often causes considerable trauma and complications, which delays treatment of the primary disease. Percutaneous vertebroplasty (PVP) is considered to be useful in achieving rapid pain control and preventing further vertebral collapse due to spinal metastasis. However, symptoms of intraspinal neural compression can be contraindications to PVP. To overcome this problem, we performed PVP following targeted bipolar radiofrequency decompression, and examined the effect of the combined treatment in relieving severe radicular pain related to spinal cord compression caused by malignant metastatic tumors. PMID:27482319

  6. Pulmonary Thermal Ablation: Comparison of Radiofrequency and Microwave Devices by Using Gross Pathologic and CT Findings in a Swine Model

    PubMed Central

    Brace, Christopher L.; Hinshaw, J. Louis; Laeseke, Paul F.; Sampson, Lisa A.; Lee, Fred T.

    2009-01-01

    Purpose: To compare the performance of equivalently sized radiofrequency and microwave ablation applicators in a normal porcine lung model. Materials and Methods: All experiments were approved by an institutional animal care and use committee. A total of 18 ablations were performed in vivo in normal porcine lungs. By using computed tomographic (CT) fluoroscopic guidance, a 17-gauge cooled triaxial microwave antenna (n = 9) and a 17-gauge cooled radiofrequency (RF) electrode (n = 9) were placed percutaneously. Ablations were performed for 10 minutes by using either 125 W of microwave power or 200 W of RF power delivered with an impedance-based pulsing algorithm. CT images were acquired every minute during ablation to monitor growth. Animals were sacrificed after the procedure. Ablation zones were then excised and sectioned transverse to the applicator in 5-mm increments. Minimum and maximum diameter, cross-sectional area, length, and circularity were measured from gross specimens and CT images. Comparisons of each measurement were performed by using a mixed-effects model; P < .05 was considered to indicate a significant difference. Results: Mean diameter (3.32 cm ± 0.19 [standard deviation] vs 2.70 cm ± 0.23, P < .001) was 25% larger with microwave ablation and mean cross-sectional area (8.25 cm2 ± 0.92 vs 5.45 cm2 ± 1.14, P < .001) was 50% larger with microwave ablation, compared with RF ablation. With microwave ablation, the zones of ablation were also significantly more circular in cross section (mean circularity, 0.90 ± 0.06 vs 0.82 ± 0.09; P < .05). One small pneumothorax was noted during RF ablation but stabilized without intervention. Conclusion: Microwave ablation with a 17-gauge high-power triaxial antenna creates larger and more circular zones of ablation than does a similarly sized RF applicator in a preclinical animal model. Microwave ablation may be a more effective treatment of lung tumors. © RSNA, 2009 PMID:19336667

  7. Superselective Particle Embolization Enhances Efficacy of Radiofrequency Ablation: Effects of Particle Size and Sequence of Action

    SciTech Connect

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

    2013-06-15

    Purpose. To evaluate the effects of particle size and course of action of superselective bland transcatheter arterial embolization (TAE) on the efficacy of radiofrequency ablation (RFA). Methods. Twenty pigs were divided into five groups: group 1a, 40-{mu}m bland TAE before RFA; group 1b, 40-{mu}m bland TAE after RFA; group 2a, 250-{mu}m bland TAE before RFA; group 2b, 250-{mu}m bland TAE after RFA and group 3, RFA alone. A total of 40 treatments were performed with a combined CT and angiography system. The sizes of the treated zones were measured from contrast-enhanced CTs on days 1 and 28. Animals were humanely killed, and the treated zones were examined pathologically. Results. There were no complications during procedures and follow-up. The short-axis diameter of the ablation zone in group 1a (mean {+-} standard deviation, 3.19 {+-} 0.39 cm) was significantly larger than in group 1b (2.44 {+-} 0.52 cm; P = 0.021), group 2a (2.51 {+-} 0.32 cm; P = 0.048), group 2b (2.19 {+-} 0.44 cm; P = 0.02), and group 3 (1.91 {+-} 0.55 cm; P < 0.001). The greatest volume of ablation was achieved by performing embolization with 40-{mu}m particles before RFA (group 1a; 20.97 {+-} 9.65 cm{sup 3}). At histology, 40-{mu}m microspheres were observed to occlude smaller and more distal arteries than 250-{mu}m microspheres. Conclusion. Bland TAE is more effective before RFA than postablation embolization. The use of very small 40-{mu}m microspheres enhances the efficacy of RFA more than the use of larger particles.

  8. Radiofrequency Ablation of Large Renal Angiomyolipoma: Median-Term Follow-Up

    SciTech Connect

    Gregory, S. M. Anderson, C. J.; Patel, U.

    2013-06-15

    Purpose. To study the feasibility of percutaneous radiofrequency ablation (RFA) of large angiomyolipomas (AMLs) using saline-cooled electrodes. Materials and Methods. Institutional Review Board approval for the study was received. Four patients (all female, age range 33-67 years) with large AMLs (maximal axis 6.1-32.4 cm) not suitable for embolotherapy or surgery consented to a trial of RFA. Procedures were performed under computerized tomographic guidance using 14G saline-infused electrodes. Two ablations (diameter 4-7 cm) were undertaken in each patient. Variables studied were technical success, treatment safety, alteration of tumor consistency, tumor size, effect on renal function, and medium-term freedom from haemorrhage. Results. All four patients underwent successful RFA without any intraprocedural complications. There has been no haemorrhage, or new renal specific symptom, during a minimum 48-month period, and normal renal function has been normal. On follow-up radiological imaging, the tumors have become fattier with involution of the soft-tissue elements (soft tissue-to-total tumor ratio decreased mean [range] of 0.26 [0.14-0.48] to 0.17 [0.04-0.34] U; p = 0.04 [paired Student t test]). Further evidence of treatment effect was the development of a capsule around the ablation zone, but there was no change in overall tumor volume (mean [range] 1,120 [118-2,845] to 1150 [90-3,013] ml; p = 1 [paired Student t test]). Conclusion. RFA of large AMLs is technically feasible using saline-infused electrodes. The soft-tissue elements decreased in volume; the tumors become fattier; and there has been no renal haemorrhage during a 48-month period.

  9. Renal Function Outcomes for Multifocal Renal Neoplasms Managed by Radiofrequency Ablation

    SciTech Connect

    Gupta, Pushpender Allen, Brian C. Chen, Michael Y. Childs, David D. Kota, Gopi Zagoria, Ronald J.

    2013-10-15

    Purpose: To evaluate renal function changes related to radiofrequency ablation (RFA) for the treatment of multifocal renal neoplasms. Methods: This is an institutional review board-approved, Health Insurance Portability and Accountability Act compliant retrospective study of all patients treated with computed tomography guided RFA for multifocal renal neoplasms at one institution. Fifty-seven subjects, mean age 70 (range 37-88) years, underwent RFA of 169 renal neoplasms (average size 2.0 cm). Subjects had between 2 and 8 (mean 2.96) neoplasms ablated. Estimated glomerular filtration rate (eGFR) was measured before and after RFA. Complications related to RFA were recorded. Results: eGFR decreased on average of 4.4 % per tumor treated and 6.7 % per ablation session (average 1.76 tumors treated per session). For subjects with the largest neoplasm measuring >3 cm, eGFR decreased an average of 14.5 % during the course of their treatment. If the largest neoplasm measured 2-3 cm, eGFR decreased an average of 7.7 %, and if the largest neoplasm measured <2 cm, eGFR decreased an average of 3.8 %. Subjects with reduced baseline renal function were more likely to have a greater decline in eGFR after RFA. There was a minor complication rate of 6.3 % (6 of 96 sessions), none of which required treatment, and a major complication rate of 4.2 % (4 of 96 sessions). Conclusion: RFA for the treatment of multifocal renal neoplasms results in mild decline of renal function.

  10. Adjuvant percutaneous radiofrequency ablation of feeding artery of hepatocellular carcinoma before treatment

    PubMed Central

    Hou, Yi-Bin; Chen, Min-Hua; Yan, Kun; Wu, Jin-Yu; Yang, Wei

    2009-01-01

    AIM: To evaluate the feasibility and efficacy of percutaneous radiofrequency ablation (RFA) of the feeding artery of hepatocellular carcinoma (HCC) in reducing the blood-flow-induced heat-sink effect of RFA. METHODS: A total of 154 HCC patients with 177 pathologically confirmed hypervascular lesions participated in the study and were randomly assigned into two groups. Seventy-one patients with 75 HCCs (average tumor size, 4.3 ± 1.1 cm) were included in group A, in which the feeding artery of HCC was identified by color Doppler flow imaging, and were ablated with multiple small overlapping RFA foci [percutaneous ablation of feeding artery (PAA)] before routine RFA treatment of the tumor. Eighty-three patients with 102 HCC (average tumor size, 4.1 ± 1.0 cm) were included in group B, in which the tumors were treated routinely with RFA. Contrast-enhanced computed tomography was used as post-RFA imaging, when patients were followed-up for 1, 3 and 6 mo. RESULTS: In group A, feeding arteries were blocked in 66 (88%) HCC lesions, and the size of arteries decreased in nine (12%). The average number of punctures per HCC was 2.76 ± 1.12 in group A, and 3.36 ± 1.60 in group B (P = 0.01). The tumor necrosis rate at 1 mo post-RFA was 90.67% (68/75 lesions) in group A and 90.20% (92/102 lesions) in group B. HCC recurrence rate at 6 mo post-RFA was 17.33% (13/75) in group A and 31.37% (32/102) in group B (P = 0.04). CONCLUSION: PAA blocked effectively the feeding artery of HCC. Combination of PAA and RFA significantly decreased post-RFA recurrence and provided an alternative treatment for hypervascular HCC. PMID:19496195

  11. Initial outcome following invasive cardiac electrophysiologic studies and radiofrequency ablation of atrial fibrillation

    PubMed Central

    Uwanuruochi, Kelechukwu; Saravanan, Sabari; Ganasekar, Anita; Solomon, Benjamin S; Murugesan, Ravikumar; Shah, Ruchit A; Krishnamoorthy, Jaishankar; Pandurangi, Ulhas M

    2016-01-01

    Background: Cardiac electrophysiologic study and radiofrequency ablation (RFA) have become an established mode of treatment for patients with refractory arrhythmias. These procedures are carried out regularly at the cardiac catheterization laboratory of Madras Medical Mission India. Objective: The purpose of this study was to evaluate our experience with cardiac electrophysiologic studies (EPS) and RFA catheter of atrial fibrillation (AF). Materials and Methods: This was a retrospective study carried out in the Cardiac Electrophysiology Department of the Institute of Cardiovascular Diseases, Madras Medical Mission, India. All cases diagnosed to have AF following cardiac EPS between January 2010 and April 2014 was selected for the study. The records, which were obtained from the Cardiac Electrophysiology Clinical Research Office of Madras Medical Mission, were reviewed. Forty-nine cases were chosen for analysis, using SPSS statistical software version 15. Results: There were 49 patients, 23 males and 26 females. The mean age was 57.53 years. Commonly associated diseases were diabetes mellitus 8 (16.3%), hypertension 18 (36.7%), and coronary heart disease 14 (28.5%). The ventricular rate was rapid most cases (91.2%). AF was diagnosed as being paroxysmal in 40 (81.6%), persistent in 5 (10.2%), chronic in 3 (6.1%), and lone in 1 (2.0%). Ablation was carried out in 28 (57.1%), the success rate being 90% for pulmonary vein isolation, and 90.9% for atrioventricular node ablation. Complication rate was 2.04%. Conclusions: Treatment of AF by RFA is highly effective and safe. PMID:27127736

  12. Real-time optical monitoring of permanent lesion progression in radiofrequency ablated cardiac tissue (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Singh-Moon, Rajinder P.; Hendon, Christine P.

    2016-02-01

    Despite considerable advances in guidance of radiofrequency ablation (RFA) therapies for atrial fibrillation, success rates have been hampered by an inability to intraoperatively characterize the extent of permanent injury. Insufficient lesions can elusively create transient conduction blockages that eventually reconduct. Prior studies suggest significantly greater met-myoglobin (Mmb) concentrations in the lesion core than those in the healthy myocardium and may serve as a marker for irreversible tissue damage. In this work, we present real-time monitoring of permanent injury through spectroscopic assessment of Mmb concentrations at the catheter tip. Atrial wedges (n=6) were excised from four fresh swine hearts and submerged under pulsatile flow of warm (37oC) phosphate buffered saline. A commercial RFA catheter inserted into a fiber optic sheath allowed for simultaneous measurement of tissue diffuse reflectance (DR) spectra (500-650nm) during application of RF energy. Optical measurements were continuously acquired before, during, and post-ablation, in addition to healthy neighboring tissue. Met-myoglobin, oxy-myoglobin, and deoxy-myoglobin concentrations were extracted from each spectrum using an inverse Monte Carlo method. Tissue injury was validated with Masson's trichrome and hematoxylin and eosin staining. Time courses revealed a rapid increase in tissue Mmb concentrations at the onset of RFA treatment and a gradual plateauing thereafter. Extracted Mmb concentrations were significantly greater post-ablation (p<0.0001) as compared to healthy tissue and correlated well with histological assessment of severe thermal tissue destruction. On going studies are aimed at integrating these findings with prior work on near infrared spectroscopic lesion depth assessment. These results support the use of spectroscopy-facilitated guidance of RFA therapies for real-time permanent injury estimation.

  13. Monitoring Radiofrequency Ablation Using Real-Time Ultrasound Nakagami Imaging Combined with Frequency and Temporal Compounding Techniques

    PubMed Central

    Zhou, Zhuhuang; Wu, Shuicai; Wang, Chiao-Yin; Ma, Hsiang-Yang; Lin, Chung-Chih; Tsui, Po-Hsiang

    2015-01-01

    Gas bubbles induced during the radiofrequency ablation (RFA) of tissues can affect the detection of ablation zones (necrosis zone or thermal lesion) during ultrasound elastography. To resolve this problem, our previous study proposed ultrasound Nakagami imaging for detecting thermal-induced bubble formation to evaluate ablation zones. To prepare for future applications, this study (i) created a novel algorithmic scheme based on the frequency and temporal compounding of Nakagami imaging for enhanced ablation zone visualization, (ii) integrated the proposed algorithm into a clinical scanner to develop a real-time Nakagami imaging system for monitoring RFA, and (iii) investigated the applicability of Nakagami imaging to various types of tissues. The performance of the real-time Nakagami imaging system in visualizing RFA-induced ablation zones was validated by measuring porcine liver (n = 18) and muscle tissues (n = 6). The experimental results showed that the proposed algorithm can operate on a standard clinical ultrasound scanner to monitor RFA in real time. The Nakagami imaging system effectively monitors RFA-induced ablation zones in liver tissues. However, because tissue properties differ, the system cannot visualize ablation zones in muscle fibers. In the future, real-time Nakagami imaging should be focused on the RFA of the liver and is suggested as an alternative monitoring tool when advanced elastography is unavailable or substantial bubbles exist in the ablation zone. PMID:25658424

  14. Fiber-optic chirped FBG for distributed thermal monitoring of ex-vivo radiofrequency ablation of liver

    PubMed Central

    Tosi, Daniele; Macchi, Edoardo Gino; Gallati, Mario; Braschi, Giovanni; Cigada, Alfredo; Rossi, Sandro; Leen, Gabriel; Lewis, Elfed

    2014-01-01

    A linearly chirped fiber Bragg grating (LCFBG) has been used as a temperature sensor for online monitoring of radiofrequency thermal ablation (RFTA). The LCFBG acts as a distributed sensor, with spatial resolution of 75 μm. A white-light setup that records the LCFBG spectrum estimates the temperature profile in real time. Three RFTA experiments have been performed ex-vivo on porcine liver measuring the radial temperature distribution during the heating process. The analysis of thermal maps quantifies the spatial heat distribution along the measurement axis and determines the ablation efficiency. PMID:24940541

  15. Outcome of radiofrequency ablation over partial nephrectomy for small renal mass (<4 cm): a systematic review and meta-analysis

    PubMed Central

    Yang, Yue; Chen, Shouzhen; Chen, Fan; Zhu, Kejia; Deng, Qiming; Luo, Li; Shi, Benkang

    2015-01-01

    Objective: A meta-analysis was undertaken to provide evidence-based clinical trials comparing radiofrequency ablation with partial nephrectomy for small renal mass. Methods: We searched through the major medical databases such as Pub Med, EMBASE, Medline, Science Citation Index, Web of Science and CNKI (Chinese National Knowledge Infrastructure Database) and Wangfang (Database of Chinese Ministry of Science & Technology) for all published studies without any limit on language from May 2007 until May 2015. The following search terms wereused: partial nephrectomy, radiofrequency ablation, renal cell carcinoma, small renal tumor or mass. Furthermore, additional related studies were manually searched in the reference lists of all published reviews and retrieved articles. Results: We found there were no statistical differences between groups in 5y-DFS, recurrence rates, complications, but a less percentage decease rate of GFR than PN, and RFA may be a better application for SRM (<4 cm). PMID:26884989

  16. Radiofrequency catheter ablation of Type 1 atrial flutter using a large-tip electrode catheter and high-power radiofrequency energy generator.

    PubMed

    Feld, Gregory K

    2004-11-01

    Recent studies have demonstrated a high degree of efficacy of 8 mm electrode-tipped or saline-irrigated-tip catheters for ablation of atrial flutter (AFL). These catheters have a theoretical advantage as they produce a large ablation lesion. However, large-tip ablation catheters have a larger surface area and require a higher power radiofrequency (RF) generator with up to 100 W capacity to produce adequate ablation temperatures (50-60 degrees C). The potential advantages of a large-tip ablation catheter and high-power RF generator include the need for fewer energy applications, shorter procedure and fluoroscopy times, and greater efficacy. Therefore, the safety and efficacy of AFL ablation using 8 or 10 mm electrode catheters and a 100-W RF generator was studied using the Boston Scientific, Inc., EPT-1000 XP cardiac ablation system. There were 169 patients, aged 61 +/- 12 years involved. Acute end points were bidirectional isthmus block and no inducible AFL. Following ablation, patients were seen at 1, 3 and 6 months, with event monitoring performed weekly and for any symptoms. Three quality of life surveys were completed during follow-up. Acute success was achieved in 158 patients (93%), with 12 +/- 11 RF energy applications. The efficacy of 8 and 10 mm electrodes did not differ significantly. The number of RF energy applications (10 +/- 8 vs. 14 +/- 8) and ablation time (0.5 +/- 0.4 vs. 0.8 +/- 0.6 h) were less with 10 mm compared with 8 mm electrodes (p < 0.01). Of 158 patients with acute success, 42 were not evaluated at 6 months due to study exclusions. Of the 116 patients evaluated at 6 months, 112 (97%) had no AFL recurrence. Of those without AFL recurrence at 6 months, 95 and 93% were free of symptoms at 12 and 24 months, respectively. Ablation of AFL improved quality of life scores (p < 0.05) and reduced anti-arrhythmic and rate control drug use (p < 0.05). Complications occurred in six out of 169 patients (3.6%) but there were no deaths. It was concluded

  17. Radiofrequency Ablation of Drug Refractory Ventricular Tachycardia Related to Cocaine Use: A Feasibility, Safety, and Efficacy Study

    PubMed Central

    LAKKIREDDY, DHANUNJAYA; KANMANTHAREDDY, ARUN; BIRIA, MAZDA; REDDY, YERUVA MADHU; PILLARISETTI, JAYASREE; MAHAPATRA, SRIJOY; BERENBOM, LOREN; CHINITZ, LARRY; ATKINS, DONITA; BOMMANA, SUDHARANI; TUNG, RODERICK; BIASE, LUIGI DI; SHIVKUMAR, KALYANAM; NATALE, ANDREA

    2014-01-01

    Background Cocaine use is a known but rare cause of cardiac arrhythmias. Ventricular arrhythmias related to cocaine may not respond to antiarrhythmic drugs and may need treatment with radiofrequency ablation. Objectives We describe the clinical and electrophysiological characteristics of cocaine-related ventricular tachycardia (VT) from a multicenter registry. Methods Subjects presenting with VT related to cocaine use and being considered for radiofrequency ablation have been included in the study. Patients who were refractory to maximal medical therapy underwent radiofrequency ablation of the VT. Clinical, procedural variables, efficacy, and safety outcomes were assessed. Results A total of 14 subjects met study criteria (age 44 ± 13, range 18-to 68-year-old with 79% male, 71% Caucasian). MRI showed evidence of scar only in 43% of patients (6/14). The mechanism of VT was focal in 50% (n = 7) and scar related reentry in 50% (n = 7) based on 3D mapping. The mean VT cycle length was 429 ± 96 milliseconds. The site of origin was epicardial in 16% (3/18) of VTs. Most clinical VTs were hemodynamically stable (75%). Mean ejection fraction at the time of admission was 44 ± 14%. Duration of procedure was 289 ± 50 minutes. One subject developed pericardial tamponade requiring drainage. At 18 ± 11 months follow-up, freedom from arrhythmia was seen in 86% (1 case lost to follow-up and 2 died). Conclusion Radiofrequency ablation is not only feasible but also safe and effective in patients who have drug refractory VT related to chronic cocaine use. PMID:24724798

  18. Image-Guided Radiofrequency Ablation of a Pancreatic Tumor with a New Triple Spiral-Shaped Electrode

    SciTech Connect

    Thanos, Loukas; Poulou, Loukia S.; Mailli, Lito; Pomoni, Maria; Kelekis, Dimitrios A.

    2010-02-15

    Image-guided, minimally invasive treatment modalities have become an area of considerable interest and research during the last few years for the treatment of primary and secondary liver tumors. We report our experience with an unresectable pancreatic tumor, treated with application of radiofrequency ablation under CT guidance that even though a complication occurred during the procedure, had excellent results on follow-up CT scans.

  19. A Case Report of 20 Lung Radiofrequency Ablation Sessions for 50 Lung Metastases from Parathyroid Carcinoma Causing Hyperparathyroidism

    SciTech Connect

    Tochio, Maki Takaki, Haruyuki; Yamakado, Koichiro; Uraki, Junji; Kashima, Masataka; Nakatsuka, Atsuhiro; Takao, Motoshi; Shimamoto, Akira; Tarukawa, Tomohito; Shimpo, Hideto; Takeda, Kan

    2010-06-15

    A 47-year-old man presented with multiple lung metastases from parathyroid carcinoma that caused hyperparathyroidism and refractory hypercalcemia. Lung radiofrequency (RF) ablation was repeated to decrease the serum calcium and parathyroid hormone levels and improve general fatigue. Pulmonary resection was combined for lung hilum metastases. The patient is still alive 4 years after the initial RF session. He has received 20 RF sessions for 50 lung metastases during this period.

  20. Mechanochemical endovenous Ablation versus RADiOfrequeNcy Ablation in the treatment of primary great saphenous vein incompetence (MARADONA): study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Radiofrequency ablation (RFA) is associated with an excellent outcome in the treatment of great saphenous vein (GSV) incompetence. The use of thermal energy as a treatment source requires the instillation of tumescence anesthesia. Mechanochemical endovenous ablation (MOCA) combines mechanical endothelial damage, using a rotating wire, with the infusion of a liquid sclerosant. Tumescence anesthesia is not required. Preliminary experiences with MOCA showed good results and low post-procedural pain. Methods/Design The MARADONA (Mechanochemical endovenous Ablation versus RADiOfrequeNcy Ablation) trial is a multicenter randomized controlled trial in which 460 patients will be randomly allocated to MOCA or RFA. All patients with primary GSV incompetence who meet the eligibility criteria will be invited to participate in this trial. The primary endpoints are anatomic and clinical success at a one-year follow-up, and post-procedural pain. The secondary endpoints are technical success, complications, operation time, procedural pain, disease-specific quality of life, time taken to return to daily activities and/or work, and cost-efficiency analyses after RFA or MOCA. Both groups will be evaluated on an intention to treat base. Discussion The MARADONA trial is designed to show equal results in anatomic and clinical success after one year, comparing MOCA with RFA. In our hypothesis MOCA has an equal anatomic and clinical success compared with RFA, with less post-procedural pain. Trial registration Clinicaltrials NCT01936168 PMID:24726004

  1. Clinical short-term results of radiofrequency ablation in liver cancers

    PubMed Central

    Jiang, Hong-Chi; Liu, Lian-Xin; Piao, Da-Xun; Xu, Jun; Zheng, Min; Zhu, An-Long; Qi, Shu-Yi; Zhang, Wei-Hui; Wu, Lin-Feng

    2002-01-01

    AIM: To study local therapeutic efficacy, side effects, and complications of radiofrequency ablation (RFA), which is emerging as a new method for the treatment of patients with hepatocellular carcinoma (HCC) with cirrhosis or chronic hepatitis and metastatic liver cancer. METHODS: Thirty-six patients with primary and secondary liver cancers (21 with primary hepatocellular carcinoma, 12 with colorectal cancer liver metastases and 3 with other malignant liver metastases), which were considered not suitable for curative resection, were include in this study. They were treated either with RFA (RITA2000, Mountain View, California, USA) percutaneously (n = 20) or intraoperatively (n = 16). The procedures were performed using the ultrasound guidance. The quality of RFA were based on monitoring of equipments and subject feeling of the practitioners. Patients treated with RFA was followed according to clinical findings, radiographic images, and tumor markers. RESULTS: Thirty-six patients underwent RFA for 48 nodules. RFA was used to treat an average 1.3 lesions per patient, and the median size of treated lesions was 2.5 cm (range, 0.5-9 cm). The average hospital stay was 5.6 d overall (2.8 d for percutaneous cases and 7.9 d for open operations). Seven patients underwent a second RFA procedure (sequential ablations). Sixteen HCC patients with a high level of alpha fetoprotein (AFP) and 9 colorectal cancer liver metastases patients with a high level of serum carcinoembryonic antigen (CEA) have a great reduction benefited from RFA. Four (11.1%) patients had complications: one skin burn; one postoperative hemorrhage; one cholecystitis and one hepatic abscess associated with percutaneous ablations of a large lesion. There were 4 deaths: 3 patients died from local and system diseases (1 at 7 month, 1 at 9 month, and 1 at 12 month), 1 patients died from cardiovascular shock, but no RFA-related death. At a median follow-up of 10 mo (range, 1-24 mo), 6 patients (16.7%) had

  2. Assessment of radiofrequency ablation margin by MRI-MRI image fusion in hepatocellular carcinoma

    PubMed Central

    Wang, Xiao-Li; Li, Kai; Su, Zhong-Zhen; Huang, Ze-Ping; Wang, Ping; Zheng, Rong-Qin

    2015-01-01

    AIM: To investigate the feasibility and clinical value of magnetic resonance imaging (MRI)-MRI image fusion in assessing the ablative margin (AM) for hepatocellular carcinoma (HCC). METHODS: A newly developed ultrasound workstation for MRI-MRI image fusion was used to evaluate the AM of 62 tumors in 52 HCC patients after radiofrequency ablation (RFA). The lesions were divided into two groups: group A, in which the tumor was completely ablated and 5 mm AM was achieved (n = 32); and group B, in which the tumor was completely ablated but 5 mm AM was not achieved (n = 29). To detect local tumor progression (LTP), all patients were followed every two months by contrast-enhanced ultrasound, contrast-enhanced MRI or computed tomography (CT) in the first year after RFA. Then, the follow-up interval was prolonged to every three months after the first year. RESULTS: Of the 62 tumors, MRI-MRI image fusion was successful in 61 (98.4%); the remaining case had significant deformation of the liver and massive ascites after RFA. The time required for creating image fusion and AM evaluation was 15.5 ± 5.5 min (range: 8-22 min) and 9.6 ± 3.2 min (range: 6-14 min), respectively. The follow-up period ranged from 1-23 mo (14.2 ± 5.4 mo). In group A, no LTP was detected in 32 lesions, whereas in group B, LTP was detected in 4 of 29 tumors, which occurred at 2, 7, 9, and 15 mo after RFA. The frequency of LTP in group B (13.8%; 4/29) was significantly higher than that in group A (0/32, P = 0.046). All of the LTPs occurred in the area in which the 5 mm AM was not achieved. CONCLUSION: The MRI-MRI image fusion using an ultrasound workstation is feasible and useful for evaluating the AM after RFA for HCC. PMID:25954109

  3. Combined Ethanol Injection Therapy and Radiofrequency Ablation Therapy in Percutaneous Treatment of Hepatocellular Carcinoma Larger than 4 cm

    SciTech Connect

    Vallone, Paolo; Catalano, Orlando Izzo, Francesco; Siani, Alfredo

    2006-08-15

    Background. Optimal treatment of large-sized hepatocellular carcinoma (HCC) is still debated, because percutaneous ablation therapies alone do not always achieve complete necrosis. Objective. To report our experience in the treatment of patients with HCC larger than 4 cm in diameter by combined percutaneous ethanol injection and radiofrequency thermal ablation. Methods. In a 5-year period there were 40 consecutive patients meeting the inclusion criteria (24 men and 16 women; age range 41-72 years, mean 58 years). These subjects had a single HCC larger than 4 cm. Twelve subjects also had one or two additional nodules smaller than 4 cm (mean 1.2 nodules per patient). Patients were submitted to one to three sessions consisting of ethanol injection at two opposite tumor poles (mean 12 ml) and then of radiofrequency application through one or two electrodes placed at the tumor center (mean treatment duration 30 min). Results. Complete necrosis was obtained in all cases with one to three sessions (mean 1.3 sessions per patient). All patients experienced pain and fever but one only subject had a major complication requiring treatment (abscess development and fistulization). Overall follow-up was 7-69 months. Two patients showed local recurrence and 9 developed new etherotopic HCC nodules. Seven subjects died during follow-up while 33 were free from recurrence 8-69 months after treatment. Conclusion. A combination of ethanol injection and radiofrequency ablation is effective in the treatment of large HCC.

  4. Endoscopic Ultrasound-Guided Radiofrequency Ablation of the Pancreatic Tumors: A Promising Tool in Management of Pancreatic Tumors

    PubMed Central

    2016-01-01

    Objective. Radiofrequency ablation is a well-established antitumor treatment and is recognized as one of the least invasive therapeutic modalities for pancreatic neoplasm. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) delivery can be used to treat both pancreatic cancer and asymptomatic premalignant pancreatic neoplasms and may serve as a less invasive alternative to surgical resection. This is an appealing option that may result in less morbidity and mortality. The aim of this review was to summarize and evaluate the clinical and technical effectiveness of EUS-guided RFA of pancreatic neoplasms. Methods. A through literature review was performed to identify the studies describing this novel technique. In this review article, we have summarized human case series. The indications, techniques, limitations, and complications reported are discussed. Results. A total of six studies were included. Overall, a 100% technical success rate was reported in human studies. Complications related to endoscopic ultrasound-guided radiofrequency ablation delivery have been described; however, few cases have presented life-threatening outcomes. Conclusion. We believe that this novel technique can be a safe and effective alternative approach in the management of selected patients. PMID:27478820

  5. Radiofrequency Ablation (RFA): Development of a Flow Model for Bovine Livers for Extensive Bench Testing

    SciTech Connect

    Lubienski, Andreas Bitsch, Rudi G.; Lubienski, Katrin; Kauffmann, Guenter; Duex, Markus

    2006-12-15

    Purpose. To develop a flow model for bovine livers for extensive bench testing of technical improvements or procedure-related developments of radiofrequency ablation excluding animal experiments. Methods. The perfusion of bovine livers directly from the slaughterhouse was simulated in a liver perfusion tank developed for the experimental work. The liver perfusion medium used was a Tyrode solution prepared in accordance with physiologic criteria (as for liver transplants) which was oxygenated by an oxygenator and heated to 36.5 deg. C. Portal vein circulation was regulated via a flow- and pressure-controlled pump and arterial circulation using a dialysis machine. Flow rate and pressure were adjusted as for the physiology of a human liver converted to bovine liver conditions. The fluid discharged from the liver was returned into the perfusion system through the vena cava. Extendable precision swivel arms with the radiofrequency probe attached were mounted on the liver perfusion tank. RFA was conducted with the RF3000 generator and a 2 cm LeVeen needle (Boston Scientific, Ratingen, Germany) in a three-dimensional grid for precise localization of the generated thermolesions. Results. Four bovine livers weighing 8.4 {+-} 0.4 kg each were prepared, connected to the perfusion system, and consecutively perfused for the experiments. Mean arterial flow was 569 {+-} 43 ml/min, arterial pressure 120 mmHg, portovenous flow 1440 {+-} 305 ml/min, and portal pressure 10 mmHg. Macroscopic evaluation after the experiments revealed no thrombi within the hepatic vessels. A total of 136 RF thermolesions were generated with an average number of 34 per liver. Mean RF duration was 2:59 {+-} 2:01 min:sec with an average baseline impedance of 28.2 {+-} 3.4 ohms. The mean diameter of the thermolesions along the puncture channel was 22.98 {+-} 4.34 mm and perpendicular to the channel was 23.27 {+-} 4.82 mm. Conclusion. Extracorporeal perfusion of bovine livers with consecutive standardized RF

  6. Endoscopic ultrasound guided radiofrequency ablation, for pancreatic cystic neoplasms and neuroendocrine tumors

    PubMed Central

    Pai, Madhava; Habib, Nagy; Senturk, Hakan; Lakhtakia, Sundeep; Reddy, Nageshwar; Cicinnati, Vito R; Kaba, Iyad; Beckebaum, Susanne; Drymousis, Panagiotis; Kahaleh, Michel; Brugge, William

    2015-01-01

    AIM: To outline the feasibility, safety, adverse events and early results of endoscopic ultrasound (EUS)-radiofrequency ablation (RFA) in pancreatic neoplasms using a novel probe. METHODS: This is a multi-center, pilot safety feasibility study. The intervention described was radiofrequency ablation (RF) which was applied with an innovative monopolar RF probe (1.2 mm Habib EUS-RFA catheter) placed through a 19 or 22 gauge fine needle aspiration (FNA) needle once FNA was performed in patients with a tumor in the head of the pancreas. The Habib™ EUS-RFA is a 1 Fr wire (0.33 mm, 0.013”) with a working length of 190 cm, which can be inserted through the biopsy channel of an echoendoscope. RF power is applied to the electrode at the end of the wire to coagulate tissue in the liver and pancreas. RESULTS: Eight patients [median age of 65 (range 27-82) years; 7 female and 1 male] were recruited in a prospective multicenter trial. Six had a pancreatic cystic neoplasm (four a mucinous cyst, one had intraductal papillary mucinous neoplasm and one a microcystic adenoma) and two had a neuroendocrine tumors (NET) in the head of pancreas. The mean size of the cystic neoplasm and NET were 36.5 mm (SD ± 17.9 mm) and 27.5 mm (SD ± 17.7 mm) respectively. The EUS-RFA was successfully completed in all cases. Among the 6 patients with a cystic neoplasm, post procedure imaging in 3-6 mo showed complete resolution of the cysts in 2 cases, whilst in three more there was a 48.4% reduction [mean pre RF 38.8 mm (SD ± 21.7 mm) vs mean post RF 20 mm (SD ± 17.1 mm)] in size. In regards to the NET patients, there was a change in vascularity and central necrosis after EUS-RFA. No major complications were observed within 48 h of the procedure. Two patients had mild abdominal pain that resolved within 3 d. CONCLUSION: EUS-RFA of pancreatic neoplasms with a novel monopolar RF probe was well tolerated in all cases. Our preliminary data suggest that the procedure is straightforward and safe. The

  7. Radiofrequency ablation following first-line transarterial chemoembolization for patients with unresectable hepatocellular carcinoma beyond the Milan criteria

    PubMed Central

    2014-01-01

    Background Recent studies suggest that a combination of radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) may have theoretical advantages over TACE alone for treatment of hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the effectiveness and safety of radiofrequency ablation following first-line TACE treatment in the management of HCC beyond the Milan Criteria. Methods Forty-five patients who consecutively underwent RFA following first-line TACE treatment for HCC beyond the Milan criteria were enrolled in this study. RFA was performed within 1–2 months after TACE treatment in patients who had incomplete necrotic tumor nodules. Primary effectiveness, complications, survival rates, and prognostic factors were evaluated retrospectively. Results Complete ablation was achieved in 76.2% of the lesions according to 1-month follow-up computed tomography/magnetic resonance imaging evaluation. The mean follow-up period was 30.9 months (range 3–94 months). There were no major complications after RFA therapy. The median overall survival was 29 months (range 20–38 months), with 1-, 2-, and 3-year survival of 89%, 61%, and 43%, respectively. Multivariate analysis revealed that tumor diameter (P = 0.045, hazard ratio [HR] = 0.228, 95% confidence interval [CI]: 0.054-0.968) and pretreatment serum alpha-fetoprotein level (P = 0.024, HR = 2.239, 95% CI: 1.114-4.500) were independent predictors for long-term survival. Conclusions HCC beyond the Milan criteria can be completely and safely ablated by radiofrequency ablation following first-line TACE treatment with a low rate of complications and favorable survival outcome. Further assessment of the survival benefits of combination treatment for HCCs beyond the Milan Criteria is warranted. PMID:24410841

  8. Radiofrequency versus Ethanol Ablation for Treating Predominantly Cystic Thyroid Nodules: A Randomized Clinical Trial

    PubMed Central

    Ha, Eun Ju; Choi, Young Jun; Sung, Jin Yong; Kim, Jae Kyun; Shong, Young Kee

    2015-01-01

    Objective To compare single-session radiofrequency ablation (RFA) and ethanol ablation (EA) for treating predominantly cystic thyroid nodules (PCTNs). Materials and Methods This single-blind, randomized trial was approved by the Institutional Review Board of two centers and informed consent was obtained from all patients before enrollment. Fifty patients with a single PCTN (cystic portion less than 90% and greater than 50%) were randomly assigned to be treated by either RFA (25 patients) or EA (25 patients) at two hospitals. The primary outcome was the tumor volume reduction ratio (%) at the six-month follow-up and the superiority margin was set at 13% (RFA minus EA). Analysis was performed primarily in an intention-to-treat manner. The secondary outcomes were the therapeutic success rate, improvement of symptomatic and cosmetic problems, and the number of major complications. Results The mean volume reduction was 87.5 ± 11.5% for RFA (n = 22) and 82.4 ± 28.6% for EA (n = 24) (p = 0.710; mean difference [95% confidence interval], 5.1% [-8.0 to 18.2]), indicating no significant difference. Regarding the secondary outcomes, therapeutic success (p = 0.490), mean symptom (p = 0.205) and cosmetic scores (p = 0.710) showed no difference. There were no major complications in either group (p > 0.99). Conclusion The therapeutic efficacy of RFA is not superior to that of EA; therefore, EA might be preferable as the first-line treatment for PCTNs. PMID:26576124

  9. Sequential activation of multiple grounding pads reduces skin heating during radiofrequency tumor ablation

    PubMed Central

    HAEMMERICH, DIETER; SCHUTT, DAVID JAMES

    2009-01-01

    Purpose Radiofrequency (RF) tumor ablation has become an accepted treatment modality for tumors not amenable to surgery. Skin burns due to ground pad heating may become a limiting factor for further increase in ablation zone dimensions and generator power. We investigated a method were groups of ground pads are sequentially activated to reduce skin heating. Methods We compared conventional operation (i.e. simultaneous connection of all pads) to sequentially switched activation of the pads where different pad combinations are active for periods of ∼0.3 − 8 s. The timing during sequential activation was adjusted to keep the leading edge temperature equal between the pads. We created Finite Element Method computer models of three pads (5 × 5 cm, 1 cm apart) placed in line with the RF electrode on a human thigh to determine differences in tissue heating during simultaneous and sequential ground pad activation. We performed experiments with three ground pads (5 × 10 cm, 4 cm apart) placed on a tissue phantom (1.5 A, 12 min) and measured pad surface and leading edge temperatures. Results Temperature rise below the leading edge for proximal, middle and distal ground pad in relation to active electrode location was 5.9°C ± 0.1°C, 0.8°C ± 0.1°C and 0.3°C ± 0.1°C for conventional operation, and 3.3°C ± 0.1°C, 3.4°C ± 0.2°C and 3.4°C ± 0.2°C for sequentially activated operation in the experiments (p < 0.001). Conclusion Sequential activation of multiple ground pads resulted in reduced maximum tissue temperature. This may reduce the incidence of ground pad burns and may allow higher power RF generators. PMID:18038286

  10. Radiofrequency Ablation of Colorectal Liver Metastases: Small Size Favorably Predicts Technique Effectiveness and Survival

    SciTech Connect

    Veltri, Andrea Sacchetto, Paola; Tosetti, Irene; Pagano, Eva; Fava, Cesare; Gandini, Giovanni

    2008-09-15

    The objective of this study was to analyze long-term results of radiofrequency thermal ablation (RFA) for colorectal metastases (MTS), in order to evaluate predictors for adverse events, technique effectiveness, and survival. One hundred ninety-nine nonresectable MTS (0.5-8 cm; mean, 2.9 cm) in 122 patients underwent a total of 166 RFA sessions, percutaneously or during surgery. The technique was 'simple' or 'combined' with vascular occlusion. The mean follow-up time was 24.2 months. Complications, technique effectiveness, and survival rates were statistically analyzed. Adverse events occurred in 8.1% of lesions (major complication rate: 1.1%), 7.1% with simple and 16.7% with combined technique (p = 0.15). Early complete response was obtained in 151 lesions (81.2%), but 49 lesions (26.3%) recurred locally after a mean of 10.4 months. Sustained complete ablation was achieved in 66.7% of lesions {<=}3 cm versus 33.3% of lesions >3 cm (p < 0.0001). Survival rates at 1, 3, and 5 years were 91%, 54%, and 33%, respectively, from the diagnosis of MTS and 79%, 38%, and 22%, respectively, from RFA. Mean survival time from RFA was 31.5 months, 36.2 in patients with main MTS {<=}3 cm and 23.2 in those with at least one lesion >3 cm (p = 0.006). We conclude that 'simple' RFA is safe and successful for MTS {<=}3 cm, contributing to prolong survival when patients can be completely treated.

  11. A case of gouty arthritis following percutaneous radiofrequency ablation for hepatocellular carcinoma

    PubMed Central

    Choi, Dae Hee; Lee, Hyo-Suk

    2010-01-01

    Percutaneous radiofrequency thermal ablation (RFA) is considered an effective technique for providing local control in the majority of Hepatocellular carcinoma (HCC) patients. Although RFA is generally well tolerated, recent studies have reported complications associated with RFA. We describe a case of acute gouty arthritis in a 71-year-old man with chronic renal failure who was treated with RFA for a HCC lesion and who had hepatitis B-associated cirrhosis and mild renal insufficiency. Regular surveillance of the patient detected a 3.5 cm HCC lesion. Because the patient had declined surgery, RFA was chosen for therapy. On the third post-procedural day, the laboratory results showed increases in his uric acid and potassium levels, which were compatible with a tumor lysis syndrome. On the 6th post-procedural day, the patient complained of new right knee pain. Subsequent joint aspiration revealed monosodium urate monohydrate crystals. We made the diagnosis of acute gouty arthritis arising from tumor lysis and liver infarction caused by HCC ablation, which was aggravated by acute renal insufficiency. After adequate hydration and administration of oral colchicines, the patient’s right knee pain subsided and the uric acid serum level returned to normal. This is the first described case of acute gouty arthritis after RFA for a HCC lesion in a patient with underlying chronic renal insufficiency. To avoid hyperuricemia and an acute attack of gout after RFA therapy for HCC, early identification of patients at risk is warranted, such as those with a large tumor, rapid tumor growth, and renal insufficiency, and preventative measures should be considered. PMID:20135729

  12. Trends in the Utilization and Impact of Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Massarweh, Nader N; Park, James O; Farjah, Farhood; Yeung, Raymond SW; Symons, Rebecca Gaston; Vaughan, Thomas L; Baldwin, Laura-Mae; Flum, David R

    2010-01-01

    Background The incidence of hepatocellular carcinoma (HCC) is rising and radiofrequency ablation (RFA) appears to be increasingly used. The nationwide use and impact of RFA have not been well characterized. Study Design Historical cohort study of US patients ≥18 years with a diagnosis of HCC (n=22,103) using the national Surveillance, Epidemiology, and End Results (SEER) limited-use database (1998-2005). Main outcome measures were receipt of different therapeutic interventions (ablation, RFA, resection, or transplantation) and adjusted one- and two- year survival. Results 4,924 (22%) patients underwent any intervention with a 93% increase over the eight year study period (trend test, p<0.001). RFA accounted for 43% of this increase. Despite increased use of therapeutic interventions, one- and two-year survival did not improve over time for patients in the study cohort (48% and 34%, 52% and 37%, 50% and 36%; in 1998, 2002, and 2004, respectively; p=0.31). Among patients with solitary lesions, adjusted one- and two-year survival remained stable over time after transplantation (97% and 94%, 95% and 89%, 94% and 86%; p=0.99) and RFA (86% and 64%, 76% and 54%; p=0.97) but improved after resection (83% and 71%, 91% and 84%, 97% and 94%; p=0.03). Conclusions Utilization of interventions for the treatment of HCC, and specifically RFA, have markedly increased over time. Since increased use of RFA among potentially resectable patients is likely to occur and because of a lack of high-level evidence supporting expanded indications, continued evaluation of the indications for RFA as well as subsequent outcomes among US patients is warranted. PMID:20347736

  13. Stereotactic Radiofrequency Ablation (SRFA) of Liver Lesions: Technique Effectiveness, Safety, and Interoperator Performance

    SciTech Connect

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

    2012-06-15

    Purpose: To evaluate technique effectiveness, safety, and interoperator performance of stereotactic radiofrequency ablation (SRFA) of liver lesions. Methods: Retrospective review including 90 consecutive patients from January 2008 to January 2010 with 106 computed tomography-guided SRFA sessions using both single and multiple electrodes for the treatment of 177 lesions: 72 hepatocellular carcinoma (HCC) and 105 metastases with a mean size of 2.9 cm (range 0.5-11 cm). Technique effectiveness and 1-year local recurrence were evaluated by computed tomographic scans. Complications, mortality, and hospital days were recorded. The performance between an experienced and inexperienced interventional radiologist was compared. Results: The overall technique effectiveness after a single SRFA was 95.5% (93.1% for HCC and 97.1% for metastases). Four of the eight unsuccessfully treated lesions could be retreated (secondary technique effectiveness of 97.7%). Local recurrence at 1 year was 2.9%. Technique effectiveness was significantly different for lesions <5 cm (96.7%) and >5 cm (87.5%) (P = 0.044) but not for lesions <3 cm (95.9%) and 3-5 cm (100%). Compared to clear parenchymal property (97.3%), vessel vicinity (93.3%) (P = 0.349) and subcapsular (95.2%) (P = 0.532) had no, but hollow viscera vicinity (83.3%) had a significantly lower technique effectiveness (P = 0.020). Mortality rate was 0.9%. Major complications and hospital days were higher for cirrhosis Child-Pugh B (20%, 7.2 days) than Child-Pugh A (3.1%, 4.7 days) patients and for metastases (5.1%, 4.3 days). There was no significant difference in interoperator performance. Conclusions: RFA allowed for efficient, reliable, and safe ablation of large-volume liver disease.

  14. Lung Tumors Treated With Percutaneous Radiofrequency Ablation: Computed Tomography Imaging Follow-Up

    SciTech Connect

    Palussiere, Jean Marcet, Benjamin; Descat, Edouard; Deschamps, Frederic; Rao, Pramod; Ravaud, Alain; Brouste, Veronique; Baere, Thierry de

    2011-10-15

    Purpose: To describe the morphologic evolution of lung tumors treated with radiofrequency ablation (RFA) by way of computed tomography (CT) images and to investigate patterns of incomplete RFA at the site of ablation. Materials and Methods: One hundred eighty-nine patients with 350 lung tumors treated with RFA underwent CT imaging at 2, 4, 6, and 12 months. CT findings were interpreted separately by two reviewers with consensus. Five different radiologic patterns were predefined: fibrosis, cavitation, nodule, atelectasis, and disappearance. The appearance of the treated area was evaluated at each follow-up CT using the predefined patterns. Results: At 1 year after treatment, the most common evolutions were fibrosis (50.5%) or nodules (44.8%). Differences were noted depending on the initial size of the tumor, with fibrosis occurring more frequently for tumors <2 cm (58.6% vs. 22.9%, P = 1 Multiplication-Sign 10{sup -5}). Cavitation and atelectasis were less frequent patterns (2.4% and 1.4%, respectively, at 1 year). Tumor location (intraparenchymatous, with pleural contact <50% or >50%) was not significantly correlated with follow-up image pattern. Local tumor progressions were observed with each type of evolution. At 1 year, 12 local recurrences were noted: 2 cavitations, which represented 40% of the cavitations noted at 1 year; 2 fibroses (1.9%); 7 nodules (7.4%); and 1 atelectasis (33.3%). Conclusion: After RFA of lung tumors, follow-up CT scans show that the shape of the treatment zone can evolve in five different patterns. None of these patterns, however, can confirm the absence of further local tumor progression at subsequent follow-up.

  15. Non-fluoroscopic navigation systems for radiofrequency catheter ablation for supraventricular tachycardia reduce ionising radiation exposure

    PubMed Central

    See, Jason; Amora, Jonah L; Lee, Sheldon; Lim, Paul; Teo, Wee Siong; Tan, Boon Yew; Ho, Kah Leng; Lee, Chee Wan; Ching, Chi Keong

    2016-01-01

    INTRODUCTION The use of non-fluoroscopic systems (NFS) to guide radiofrequency catheter ablation (RFCA) for the treatment of supraventricular tachycardia (SVT) is associated with lower radiation exposure. This study aimed to determine if NFS reduces fluoroscopy time, radiation dose and procedure time. METHODS We prospectively enrolled patients undergoing RFCA for SVT. NFS included EnSite™ NavX™ or CARTO® mapping. We compared procedure and fluoroscopy times, and radiation exposure between NFS and conventional fluoroscopy (CF) cohorts. Procedural success, complications and one-year success rates were reported. RESULTS A total of 200 patients over 27 months were included and RFCA was guided by NFS for 79 patients; those with atrioventricular nodal reentrant tachycardia (AVNRT), left-sided atrioventricular reentrant tachycardia (AVRT) and right-sided AVRT were included (n = 101, 63 and 36, respectively). Fluoroscopy times were significantly lower with NFS than with CF (10.8 ± 11.1 minutes vs. 32.0 ± 27.5 minutes; p < 0.001). The mean fluoroscopic dose area product was also significantly reduced with NFS (NSF: 5,382 ± 5,768 mGy*cm2 vs. CF: 21,070 ± 23,311 mGy*cm2; p < 0.001); for all SVT subtypes. There was no significant reduction in procedure time, except for left-sided AVRT ablation (NFS: 79.2 minutes vs. CF: 116.4 minutes; p = 0.001). Procedural success rates were comparable (NFS: 97.5% vs. CF: 98.3%) and at one-year follow-up, there was no significant difference in the recurrence rates (NFS: 5.2% vs. CF: 4.2%). No clinically significant complications were observed in both groups. CONCLUSION The use of NFS for RFCA for SVT is safe, with significantly reduced radiation dose and fluoroscopy time. PMID:26805664

  16. Effect of Diameter of Saphenous Vein on Stump Length after Radiofrequency Ablation for Varicose Vein

    PubMed Central

    Kim, Jusung; Cho, Sungsin; Joh, Jin Hyun; Ahn, Hyung-Joon; Park, Ho-Chul

    2015-01-01

    Purpose: Radiofrequency ablation (RFA) has gained popularity for treatment of varicose veins. The diameter of the saphenous vein should be considered before RFA because occlusion of the vein may differ depending on its diameter. Until now, however, there have been few data about the correlation between the diameter of the saphenous vein and the stump length after RFA. The purpose of our study was to investigate its correlation. Materials and Methods: A retrospective review was performed from prospectively collected data of RFA patients between March 2009 and December 2011. Preoperatively, the saphenous vein diameter was measured. Ablation was initiated 2 cm distal from the junction. Postoperatively, stump length was measured at 1 week and 6 months. After 2 years, we measured the length from the saphenofemoral junction to the leading point of occlusion for great saphenous vein, and length from the saphenopopliteal junction to the leading point of occlusion for small saphenous vein. The paired t-test, independent t-test, and correlation analysis were used for statistical analysis. P-value <0.05 was considered statistically significant. Results: During the study period, RFA was performed in 201 patients. Endovenous heat-induced thrombosis developed in 3 patients (1.5%). After 2 years, the stump length was obtained in 74 limbs. The mean diameter and stump length of the saphenous vein were 6.7±1.8 mm and 12.5±8.5 mm, respectively. Correlation analysis showed that the Pearson correlation coefficient of these factors was −0.017. Conclusion: There was no correlation between the diameter of saphenous vein and stump length. PMID:26719839

  17. Influence of Surgical Staples on Radiofrequency Ablation Using Multitined Expandable Electrodes

    SciTech Connect

    Sakuhara, Yusuke Shimizu, Tadashi; Abo, Daisuke; Hasegawa, Yu; Kato, Fumi; Kodama, Yoshihisa; Shirato, Hiroki

    2007-11-15

    Purpose. During radiofrequency ablation (RFA), there is a risk that the multitined expandable electrode will come into contact with one of the surgical staples used to treat local recurrence after surgical operations. Our objective was to evaluate whether a surgical staple would influence the RFA of egg white using a multitined expandable electrode. Methods. Multitined expandable electrodes, LeVeen needles (expandable diameter 3.0 cm), were sunk into an egg white bath with (a) no surgical staple, (b) a surgical staple touching one of the tines, or (c) a surgical staple touching two of the tines simultaneously. By connecting the LeVeen needle and copper plate at the bottom of the bath, RFA was then performed on the egg whites as a substitute for human tissue. Ten egg white baths were ablated under each of conditions (a), (b), and (c), for a total of 30 sets of coagulated egg white. Results. There was no significant difference in the time from the power-on to the roll-off (i.e., the completion and shutting off of the electric circuit) or in the maximum diameter of the thermal lesion between conditions (a) and (b) or (a) and (c). However, the minimum diameter of the thermal lesion was significantly smaller in (c) compared with (a) (p < 0.01). Conclusions. Surgical staples have the capacity to interfere with the electromagnetic field and decrease the minimum diameter of the thermal lesion in the event that a staple touches two of the tines of a multitined expandable electrode during RFA. Although the difference might be small enough to be neglected under many clinical circumstances, we recommend that, if possible, the tines not be expanded near metallic material.

  18. NON-INVASIVE RADIOFREQUENCY ABLATION OF CANCER TARGETED BY GOLD NANOPARTICLES

    PubMed Central

    Cardinal, Jon; Klune, John Robert; Chory, Eamon; Jeyabalan, Geetha; Kanzius, John S.; Nalesnik, Michael; Geller, David A.

    2008-01-01

    Introduction Current radiofrequency ablation (RFA) techniques require invasive needle placement and are limited by accuracy of targeting. The purpose of this study was to test a novel non-invasive radiowave machine that uses RF energy to thermally destroy tissue. Gold nanoparticles were designed and produced to facilitate tissue heating by the radiowaves. Methods A solid state radiowave machine consisting of a power generator and transmitting/receiving couplers which transmit radiowaves at 13.56 MHz was used. Gold nanoparticles were produced by citrate reduction and exposed to the RF field either in solutions testing or after incubation with HepG2 cells. A rat hepatoma model using JM-1 cells and Fisher rats was employed using direct injection of nanoparticles into the tumor to focus the radiowaves for select heating. Temperatures were measured using a fiber-optic thermometer for real-time data. Results Solutions containing gold nanoparticles heated in a time- and power-dependent manner. HepG2 liver cancer cells cultured in the presence of gold nanoparticles achieved adequate heating to cause cell death upon exposure to the RF field with no cytotoxicity attributable to the gold nanoparticles themselves. In vivo rat exposures at 35W using gold nanoparticles for tissue injection resulted in significant temperature increases and thermal injury at subcutaneous injection sites as compared to vehicle (water) injected controls. Discussion These data show that non-invasive radiowave thermal ablation of cancer cells is feasible when facilitated by gold nanoparticles. Future studies will focus on tumor selective targeting of nanoparticles for in vivo tumor destruction. PMID:18656617

  19. Radiofrequency Ablation Compared to Surgery for the Treatment of Benign Thyroid Nodules

    PubMed Central

    Bernardi, Stella; Dobrinja, Chiara; Fabris, Bruno; Bazzocchi, Gabriele; Sabato, Nicoletta; Ulcigrai, Veronica; Giacca, Massimo; Barro, Enrica; De Manzini, Nicolò; Stacul, Fulvio

    2014-01-01

    Objective. Benign thyroid nodules are a common occurrence whose only remedy, in case of symptoms, has always been surgery until the advent of new techniques, such as radiofrequency ablation (RFA). This study aimed at evaluating RFA efficacy, tolerability, and costs and comparing them to hemithyroidectomy for the treatment of benign thyroid nodules. Design and Methods. 37 patients who underwent RFA were retrospectively compared to 74 patients surgically treated, either in a standard inpatient or in a short-stay surgical regimen. Efficacy, tolerability, and costs were compared. The contribution of final pathology was also taken into account. Results. RFA reduced nodular volume by 70% after 12 months and it was an effective method for treating nodule-related clinical problems, but it was not as effective as surgery for the treatment of hot nodules. RFA and surgery were both safe, although RFA had less complications and pain was rare. RFA costed €1,661.50, surgery costed €4,556.30, and short-stay surgery costed €4,139.40 per patient. RFA, however, did not allow for any pathologic analysis of the nodules, which, in 6 patients who had undergone surgery (8%), revealed that the nodules harboured malignant cells. Conclusions. RFA might transform our approach to benign thyroid nodules. PMID:25045352

  20. Radio-frequency ablation-based studies on VX2rabbit models for HCC treatment.

    PubMed

    Bimonte, Sabrina; Leongito, Maddalena; Piccirillo, Mauro; de Angelis, Cristina; Pivonello, Claudia; Granata, Vincenza; Izzo, Francesco

    2016-01-01

    Hepatocellular carcinoma (HCC) is the fifth most frequent cancer worldwide with high morbidity, mortality and increasing incidence. It is of note that the main curative therapies for HCC are hepatic resection and transplantation although the majority of patients at the time of presentation are not eligible for resection or orthotopic liver transplantation (OLT) due to the underlying cirrhosis. Currently, a variety of loco-regional therapies, including radiofrequency ablation (RFA), percutaneous ethanol injection (PEI), microwave coagulation therapy (MCT), transarterial chemoembolization (TACE) and others, have been developed as alternative treatment options for HCC. Among these techniques, RFA is currently the most widely used treatment, due to its several advantages, such as safety and efficacy. To date, the effectiveness of RFA for HCC is reduced by the presence of residual tumor as a consequence of insufficient treatment. In order to ameliorate the effects of RFA on HCC, several in vivo studies, have been performed on its application as single or in combination treatment with drugs or others loco-regional therapies, by using rabbit VX2 liver model. This represents an ideal model of liver cancers and is widely used for imaging and other experimental studies due to the rapid growth of these tumors and their similarity to human hepatocellular carcinoma. In order to elucidate the therapeutic potential of RFA with adjuvant treatments for HCC, we reviewed the latest findings on the RFA-based studies in rabbit VX2 hepatocarcinoma models. PMID:27525037

  1. Novel use of epidural catheter: Air injection for neuroprotection during radiofrequency ablation of spinal osteoid osteoma.

    PubMed

    Doctor, J R; Solanki, S L; Patil, V P; Divatia, J V

    2016-01-01

    Osteoid osteoma (OO) is a benign bone tumor, with a male-female ratio of approximately 2:1 and mainly affecting long bones. Ten percent of the lesions occur in the spine, mostly within the posterior elements. Treatment options for OO include surgical excision and percutaneous imaging-guided radiofrequency ablation (RFA). Lesions within the spine have an inherent risk of thermal damage to the vital structure because of proximity to the neural elements. We report a novel use of the epidural catheter for air injection for the neuroprotection of nerves close to the OO of the spine. A 12-year-old and 30 kg male child with an OO of the L3 vertebra was taken up for RFA. His preoperative examinations were within normal limits. The OO was very close to the L3 nerve root. Under general anesthesia, lumbar epidural catheter was placed in the L3-L4 space under imaging guidance. Ten ml of aliquots of air was injected under imaging guidance to avoid injury to the neural structures due to RFA. The air created a gap between neural elements and the tumor and served as an insulating material thereby protecting the neural elements from damage due to the RFA. Postoperatively, the patient did not develop any neurological deficit. PMID:27375396

  2. Value of Implantable Loop Recorders in Monitoring Efficacy of Radiofrequency Catheter Ablation in Atrial Fibrillation

    PubMed Central

    Yang, Ping; Pu, Lijin; Yang, Liuqing; Li, Fang; Luo, Zhiling; Guo, Tao; Hua, Baotong; Li, Shumin

    2016-01-01

    Background The aim of this study was to evaluate the value of the implantable loop recorder (ILR) in diagnosing atrial fibrillation (AF) and assessing the postoperative efficacy of radiofrequency catheter ablation (RFCA). Material/Methods A total of 32 patients who successfully underwent RFCA were selected. These patients discontinued antiarrhythmic medication with no AF recurrence for more than 3 months after RFCA, and underwent ILR placement by a conventional method. The clinical manifestations and information on arrhythmias recorded by the ILR were followed up to assess the efficacy of AF RFCA. Results The mean follow-up period was 24.7±12.5 months. Of 32 patients with ILR information, 27 had successful RFCA and 5 had recurrent AF. The follow-up results obtained by traditional methods showed 29 patients with successful RFCA and 3 with recurrent AF (P<0.05). Among the 18 patients with clinical symptoms, 13 had recorded cardiac arrhythmic events (72.2%) and 5 showed sinus rhythm (27.8%). The ILRs recorded 18 patients with arrhythmic events (56.3%), including 12 cases of atrial arrhythmias, among whom 5 recurred at 9, 12, 16, 17, and 32 months after AF RFCA; there were also 2 patients with ventricular tachycardia (VT) and 4 with bradycardia. Conclusions The value of ILR in assessing the efficacy of AF RFCA was superior to that of traditional methods. ILR can promptly detect asymptomatic AF, and can monitor electrocardiogram features after RFCA, thus providing objective evidence of efficacy. PMID:27518153

  3. Novel use of epidural catheter: Air injection for neuroprotection during radiofrequency ablation of spinal osteoid osteoma

    PubMed Central

    Doctor, JR; Solanki, SL; Patil, VP; Divatia, JV

    2016-01-01

    Osteoid osteoma (OO) is a benign bone tumor, with a male-female ratio of approximately 2:1 and mainly affecting long bones. Ten percent of the lesions occur in the spine, mostly within the posterior elements. Treatment options for OO include surgical excision and percutaneous imaging-guided radiofrequency ablation (RFA). Lesions within the spine have an inherent risk of thermal damage to the vital structure because of proximity to the neural elements. We report a novel use of the epidural catheter for air injection for the neuroprotection of nerves close to the OO of the spine. A 12-year-old and 30 kg male child with an OO of the L3 vertebra was taken up for RFA. His preoperative examinations were within normal limits. The OO was very close to the L3 nerve root. Under general anesthesia, lumbar epidural catheter was placed in the L3-L4 space under imaging guidance. Ten ml of aliquots of air was injected under imaging guidance to avoid injury to the neural structures due to RFA. The air created a gap between neural elements and the tumor and served as an insulating material thereby protecting the neural elements from damage due to the RFA. Postoperatively, the patient did not develop any neurological deficit. PMID:27375396

  4. Biliary tract perforation following percutaneous endobiliary radiofrequency ablation: A report of two cases

    PubMed Central

    ZHOU, CHUANGUO; WEI, BAOJIE; GAO, KUN; ZHAI, RENYOU

    2016-01-01

    Endobiliary radiofrequency ablation (RFA) has recently been recognized as a beneficial treatment option for malignant biliary obstruction using percutaneous or endoscopic approaches. The feasibility and safety of this method has been demonstrated in clinical studies, with pain, cholangitis and asymptomatic biochemical pancreatitis reported as relatively common complications. By contrast, hepatic coma, newly diagnosed left bundle branch block and partial liver infarction have been reported as uncommon complications. Biliary tract perforation is a serious potential complication of percutaneous intraductal RFA, which may result in severe infection, peritonitis or even mortality, and which has not been previously reported in clinical research. The current study presents the first reports of biliary tract perforation in two patients with unresectable malignant biliary obstruction following percutaneous intraductal RFA. Although the patient in case 1 succumbed 12 days after RFA, the minor biliary tract perforation in case 2 was successfully treated by the deployment of a self-expanding metal stent. This study demonstrates that biliary tract perforation should be recognized as a serious potential complication of endobiliary RFA, and that metal stent deployment should be considered as a treatment option for minor biliary tract perforation. PMID:27313699

  5. In vivo immunological antitumor effect of OK-432-stimulated dendritic cell transfer after radiofrequency ablation.

    PubMed

    Nakagawa, Hidetoshi; Mizukoshi, Eishiro; Iida, Noriho; Terashima, Takeshi; Kitahara, Masaaki; Marukawa, Yohei; Kitamura, Kazuya; Nakamoto, Yasunari; Hiroishi, Kazumasa; Imawari, Michio; Kaneko, Shuichi

    2014-04-01

    Radiofrequency ablation therapy (RFA) is a radical treatment for liver cancers and induces tumor antigen-specific immune responses. In the present study, we examined the antitumor effects of focal OK-432-stimulated dendritic cell (DC) transfer combined with RFA and analyzed the functional mechanisms involved using a murine model. C57BL/6 mice were injected subcutaneously with colon cancer cells (MC38) in their bilateral flanks. After the establishment of tumors, the subcutaneous tumor on one flank was treated using RFA, and then OK-432-stimulated DCs were injected locally. The antitumor effect of the treatment was evaluated by measuring the size of the tumor on the opposite flank, and the immunological responses were assessed using tumor-infiltrating lymphocytes, splenocytes and draining lymph nodes. Tumor growth was strongly inhibited in mice that exhibited efficient DC migration after RFA and OK-432-stimulated DC transfer, as compared to mice treated with RFA alone or treatment involving immature DC transfer. We also demonstrated that the antitumor effect of this treatment depended on both CD8-positive and CD4-positive cells. On the basis of our findings, we believe that combination therapy for metastatic liver cancer consisting of OK-432-stimulated DCs in combination with RFA can proceed to clinical trials, and it is anticipated to be markedly superior to RFA single therapy. PMID:24384836

  6. Clinical Experience of Bronchoscopy-Guided Radiofrequency Ablation for Peripheral-Type Lung Cancer

    PubMed Central

    Koizumi, Tomonobu; Kobayashi, Takashi; Tanabe, Tsuyoshi; Tsushima, Kenji; Yasuo, Masanori

    2013-01-01

    We have developed a new internal cooled electrode for radiofrequency ablation (RFA) (Japan Application no. 2006-88228) suitable for forceps channel bronchoscopy. Here, we present our clinical experience with bronchoscopy-guided RFA under computed tomography (CT) monitoring for patients with peripheral-type non-small-cell lung cancer (NSCLC). Bronchoscopy-guided RFA was performed in two patients (80 and 70 years old) with NSCLC, who had no lymph node involvement and distant metastases (T1N0M0), but not indicated for surgery because of other complications, such as advanced age, poor pulmonary function, and refusal of thoracic surgery. The locations of the tumors were right S2 and left S3, respectively. Although the tumors showed ground-glass opacity (GGO) with solid components in both cases, radiographic findings changed to reduced mass-like shadow and remained stable for 4 and 3.5 years after bronchoscopy-guided RFA. As the former case developed progressive disease on chest CT, bronchoscopy-guided RFA was repeated in the same lesion, resulting in no change for the subsequent 1 year. There were no adverse reactions during the procedures. Thus, bronchoscopy-guided RFA is a safe and feasible procedure that represents a potentially useful therapeutic tool in local control in medically inoperable patients with stage I NSCLC. PMID:24106625

  7. Risk factors for deterioration of long-term liver function after radiofrequency ablation therapy

    PubMed Central

    Honda, Koichi; Seike, Masataka; Oribe, Junya; Endo, Mizuki; Arakawa, Mie; Syo, Hiroki; Iwao, Masao; Tokoro, Masanori; Nishimura, Junko; Mori, Tetsu; Yamashita, Tsutomu; Fukuchi, Satoshi; Muro, Toyokichi; Murakami, Kazunari

    2016-01-01

    AIM: To identify factors that influence long-term liver function following radiofrequency ablation (RFA) in patients with viral hepatitis-related hepatocellular carcinoma. METHODS: A total of 123 patients with hepatitis B virus- or hepatitis C virus-related hepatocellular car-cinoma (HCC) (n = 12 and n = 111, respectively) were enrolled. Cumulative rates of worsening Child-Pugh (CP) scores (defined as a 2-point increase) were examined. RESULTS: CP score worsening was confirmed in 22 patients over a mean follow-up period of 43.8 ± 26.3 mo. Multivariate analysis identified CP class, platelet count, and aspartate aminotransferase levels as signi-ficant predictors of a worsening CP score (P = 0.000, P = 0.011 and P = 0.024, respectively). In contrast, repeated RFA was not identified as a risk factor for liver function deterioration. CONCLUSION: Long-term liver function following RFA was dependent on liver functional reserve, the degree of fibrosis present, and the activity of the hepatitis condition for this cohort. Therefore, in order to maintain liver function for an extended period following RFA, suppression of viral hepatitis activity is important even after the treatment of HCC. PMID:27168872

  8. Clinical utility of the Covidien Closure Fast™ Endovenous Radiofrequency Ablation Catheter

    PubMed Central

    Braithwaite, Simon A; Braithwaite, Bruce D

    2014-01-01

    The Closure Fast™ Endovenous Radiofrequency Ablation Catheter is the latest version of a minimally invasive system for the treatment of patients with superficial venous disease. The Closure Fast™ catheter heats the vein wall to 120°C, causing denaturation of the collagen of the vein wall and contraction of the vessel such that no blood can flow through it. Nearly one million systems have been sold since the product was launched. Many, if not all, patients can be treated under local anesthesia with the Closure Fast™ catheter. Duplex ultrasound reports occlusion rates for the treated vein of 94%–98% at 1 year and 85%–93% at 3 years. The system produces average postoperative pain scores of less than 2 out of 10 on a visual analog score. In the first postoperative week, 76% of patients do not require analgesia. Some 45% of patients return to normal activity on the first postoperative day. Serious complications appear to be rare following the Closure Fast™ procedure. Transient paresthesia occurs in 0.2% of cases, thrombophlebitis in 1%–10%, and thromboembolic events in up to 1.4%, mainly heat-induced thrombosis. Closure Fast™ adds significant costs to treating superficial venous disease but studies have shown it to be cost-effective when used in an office setting. PMID:24940086

  9. Radiofrequency ablation for oral and maxillofacial pathologies: A description of the technique

    NASA Astrophysics Data System (ADS)

    Tandon, Rahul; Stevens, Timothy W.; Herford, Alan S.

    2014-03-01

    Introduction: Radiofrequency ablation (RFA) refers to a high-frequency current that heats and coagulates tissue. In the standard RFA setup, three components are used: a generator, an active electrode, and a dispersive electrode. RFA has garnered support in many of the surgical fields as an alternative to traditional procedures used in tumor removal. Other methods can prove to be more invasive and disfiguring to the patient, in addition to the unwarranted side effects; however, RFA provides a more localized treatment, resulting in decreased co-morbidity to the patient. Currently, its use in the field of oral and maxillofacial surgery is limited, as its technology has not reached our field. By describing its limited use to the optics community, we hope to expand its uses and provide patients with one more alternative treatment option. Methods and Uses: We will describe the use of RFA on three types of pathology: lymphangioma, rhabdomyoscarcoma, oral squamous cell carcinoma, and neoplastic osseous metastasis. The majority of treatments geared towards these pathologies involve surgical resection, followed by reconstruction. However, damage to vital structures coupled with esthetic disfigurement makes RFA a more valuable alternative. In many of the cases, the tumors were successfully removed without recurrence. Conclusion: While the use of RFA has been scarce in our field, we believe that with more exposure it can gain momentum as an alternative to current treatment options. However, there are improvements that we feel can be made, helping to maximize its effectiveness.

  10. Pulsed radiofrequency ablation for residual and phantom limb pain: a case series.

    PubMed

    West, Matt; Wu, Hong

    2010-01-01

    Residual limb pain (RLP) and phantom limb pain (PLP) can be debilitating and can prevent functional gains following amputation. High correlations have been reported between RLP and the stump neuromas following amputation. Many treatment methods including physical therapy, medications, and interventions, have been used with limited success. Pulsed radiofrequency ablation (PRFA) has shown promise in treating neuropathic pain because of the inhibition of evoked synaptic activity. We present 4 amputees who were treated with PRFA after failing conservative management for their RLP and PLP. All 4 patients underwent PRFA and demonstrated at least 80% relief of RLP for over 6 months. One patient reported a complete resolution of phantom sensation while another patient had significantly decreased frequency of spontaneous PLP and resolution of evoked PLP. In addition, all patients reported improved overall function including increased prosthetic tolerance and decreased oral pain medications. This case series suggests that PRFA is a viable treatment option which might be used for long-term relief of intractable RLP and/or PLP. PMID:20230449

  11. Development of a Swine Benign Biliary Stricture Model Using Endoscopic Biliary Radiofrequency Ablation.

    PubMed

    Park, Jin Seok; Jeong, Seok; Kim, Joon Mee; Park, Sang Soon; Lee, Don Haeng

    2016-09-01

    The large animal model with benign biliary stricture (BBS) is essential to undergo experiment on developing new devices and endoscopic treatment. This study conducted to establish a clinically relevant porcine BBS model by means of endobiliary radiofrequency ablation (RFA). Endoscopic retrograde cholangiography (ERC) was performed on 12 swine. The animals were allocated to three groups (60, 80, and 100 W) according to the electrical power level of RFA electrode. Endobiliary RFA was applied to the common bile duct for 60 seconds using an RFA catheter that was endoscopically inserted. ERC was repeated two and four weeks, respectively, after the RFA to identify BBS. After the strictures were identified, histologic evaluations were performed. On the follow-up ERC two weeks after the procedure, a segmental bile duct stricture was observed in all animals. On microscopic examination, severe periductal fibrosis and luminal obliteration with transmural inflammation were demonstrated. Bile duct perforations occurred in two pigs (100 W, n = 1; 80 W, n = 1) but there were no major complications in the 60 W group. The application of endobiliary RFA with 60 W electrical power resulted in a safe and reproducible swine model of BBS. PMID:27510388

  12. Adjunctive radiofrequency ablation for the endoscopic treatment of ampullary lesions with intraductal extension (with video)

    PubMed Central

    Suarez, Alejandro L.; Coté, Gregory A.; Elmunzer, B. Joseph

    2016-01-01

    Background and study aims: Catheter-based radiofrequency ablation (RFA) delivered during endoscopic retrograde cholangiopancreatography (ERCP) may represent a viable treatment option for intraductal extension of ampullary neoplasms, however, clinical experience with this modality is limited. After ampullary resection, 4 patients with intraductal extension underwent adjunctive RFA of the distal bile duct. All patients received a temporary pancreatic stent to reduce the risk of pancreatitis, as well as a plastic biliary stent to prevent biliary obstruction. Three patients were treated for adenoma and 1 for adenoma with a focus of adenocarcinoma. During a short follow-up period, 3 patients experienced complete eradication of the target lesion, whereas the patient with a focus of adenocarcinoma had progression to overt invasive cancer. There were no immediate adverse events. One patient developed a post-RFA bile duct stricture, which has required additional endoscopic therapy. Catheter-based RFA of ampullary lesions that extend up the bile duct is technically feasible. Additional research is necessary to understand the risks and long-term benefits of this technique.

  13. In vivo intracardiac OCT imaging through percutaneous access: towards image guided radio-frequency ablation

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Kang, Wei; Carrigan, Thomas; Bishop, Austin; Rosenthal, Noah; Arruda, Mauricio; Rollins, Andrew M.

    2012-01-01

    BACKGROUND Complete catheter-tissue contact and permanent tissue destruction are essential for efficient radio-frequency ablation (RFA) during cardiac arrhythmia treatment. Current methods of monitoring lesion formation are indirect and unreliable. We aim to develop optical coherence tomography (OCT) as an imaging guidance for RFA. OBJECTIVES The purpose of this study is to evaluate the feasibility of using OCT catheter to image endocardia wall in active beating hearts through percutaneous access. This is a critical step toward image guided RFA in a clinic setting. METHODS A cone-scanning forward-viewing OCT catheter was advanced into active beating hearts through percutaneous access in four swine. The OCT catheter was steered by an introducer to touch the endocardia wall. The images were then acquired at 10 frames per second at an axial resolution and lateral resolution of 15 μm. RESULTS We report the first in vivo intracardiac OCT imaging through percutaneous access with a thin and flexible OCT catheter. We are able to acquire high quality OCT images in active beating hearts, observe the polarization-related artifacts induced by the birefringence of myocardium and readily evaluate catheter-tissue contact. CONCLUSIONS It is feasible to acquire OCT images in beating hearts through percutaneous access. The observations indicate that OCT could be a promising technique for in vivo guidance of RFA.

  14. [Long-term results of low-speed irrigated radiofrequency catheter ablation of atrial flutter].

    PubMed

    Ardashev, V N; Ardashev, A V; Novichkov, S A; Konev, A V; Voloshko, S V; Shavarov, A A

    2007-01-01

    The authors studied long-term results of low-speed (10 ml/min) irrigated radiofrequency catheter ablation (RFA) of the lower isthmus (LI) in patients with typical atrial flutter (AF). This treatment was based upon combined use of local and indirect criteria of the block of isthmus conduction. The influence of RFA LI on quality of life (QL), echocardiographic parameters and cardiac rhythm variability (CRV) was studied. Low-speed irrigated RFA LI, based upon combined use of local and indirect criteria for verification of complete bidirectional blockade in this area, is an effective and safe method of treatment of patients with different variants of clinical course of typical AF which makes it possible to significantly improve QL characteristics and central hemodynamic parameters, and normalize CVR parameters as well. Self-organization of chaos, which realizes according to RR interval time rows, in patients with typical AF after RFA LI may be considered an additional criterion of the effectiveness of this operative intervention and a prognostic sign that predicts maintenance of sinus rhythm in this category of patients. PMID:17601035

  15. Molecular targeting agents associated with transarterial chemoembolization or radiofrequency ablation in hepatocarcinoma treatment

    PubMed Central

    Ranieri, Girolamo; Marech, Ilaria; Lorusso, Vito; Goffredo, Veronica; Paradiso, Angelo; Ribatti, Domenico; Gadaleta, Cosmo Damiano

    2014-01-01

    Hepatocellular carcinoma (HCC) is the fifth most common cause of cancer in the world. According to Barcelona Clinic Liver Cancer modified criteria, patients with early stage disease are candidate to radiofrequency ablation (RFA), while patients with intermediate stage HCC are usually treated by transarterial chemoembolization (TACE). TACE and RFA induce a transient devascularisation effect followed by strong neo-angiogenic stimulus. In fact, after these procedures, it has been demonstrated an up-regulation of pro-angiogenic and growth factors such as vascular endothelial growth factor-A, which might contribute to accelerated progression in patients with incomplete response. Several studies have demonstrated that MAP-kinase and AKT pathways, in addition to neo-angiogenesis, have an important role in the development of HCC. In advanced HCC, anti-angiogenic therapy and tyrosine kinases inhibitors showed potential clinical benefit. Actually, a number of clinical studies are ongoing testing these agents in combination with TACE or RFA. In this paper, we have reviewed the most recent preclinical and clinical results of such trials. PMID:24574717

  16. Late-onset diaphragmatic hernia after percutaneous radiofrequency ablation of hepatocellular carcinoma: a case study.

    PubMed

    Abe, Tomoyuki; Amano, Hironobu; Takechi, Hitomi; Fujikuni, Nobuaki; Sasada, Tatsunari; Yoshida, Makoto; Yamaki, Minoru; Nakahara, Masahiro; Noriyuki, Toshio

    2016-12-01

    Percutaneous radiofrequency ablation (RFA) is widely used as an effective treatment of liver tumors. Several reported complications associated with RFA are due to thermal damage of neighboring organs. The present report presents a case of diaphragmatic hernia associated with RFA and hepatocellular carcinoma (HCC). A 72-year-old woman with S5 and S8 HCCs was treated repeatedly with RFA and transcatheter arterial chemoembolization for 3 years. After the third course of RFA to target the recurring S5 HCC, acute abdominal pain and dyspnea suddenly occurred. Contrast-enhanced computed tomography revealed intrusion of the transverse colon through the right diaphragmatic hernia. In addition, the colon was dilated and showed changes suggestive of ischemic conditions. An emergency surgery was performed to close the hernia by using non-absorbable sutures to preserve the colon. The patient was discharged without any complications 13 days after the surgery. The first-line treatment of this disease involves surgical intervention. Diaphragmatic hernia is a rare complication of RFA. The present case suggests that patients who undergo several rounds of RFA require surveillance for diaphragmatic hernias. PMID:26976615

  17. Intraoperative radiofrequency ablation for metastatic spine disease: report of 4 cases and review.

    PubMed

    Ha, Kee-Yong; Kim, Young-Hoon; Yoo, Tae-Wook

    2013-11-01

    Metastatic spine disease (MSD) is a complex disease entity requiring multi-discipline and multi-modality approach to obtain the most reasonable clinical outcomes. As one of these trials, radiofrequency ablation (RFA) has been tried. Here, we describe four cases of metastatic spine lesions (2 hepatomas, 1 lung cancer, 1 breast cancer) that were treated with intraoperative RFA to control the lesion and to limit tumor contamination. During 3-month follow-up, most patients experienced effective pain relief and improvement of their functional status. However, their final results were diverse. There were no complications related to this procedure. In two cases, the treated lesions were re-evaluated radiologically using PET-CT and diffusion-weighted MRI. Up to the time of this report, the patients are well without progressive deterioration of the treated lesion. With review of the related literatures, we discuss the efficacy and safety of this therapeutic approach as one of options for the treatment of MSD with neurologic manifestations. PMID:23412181

  18. Radiofrequency ablation versus resection for Barcelona clinic liver cancer very early/early stage hepatocellular carcinoma: a systematic review

    PubMed Central

    He, Zhen-Xin; Xiang, Pu; Gong, Jian-Ping; Cheng, Nan-Sheng; Zhang, Wei

    2016-01-01

    Aim To compare the long-term survival outcomes of radiofrequency ablation and liver resection for single very early/early stage hepatocellular carcinoma (HCC). Methods The Cochrane Library (Issue 3, 2015), Embase (1974 to March 15, 2015), PubMed (1950 to March 15, 2015), Web of Science (1900 to March 15, 2015), and Chinese Biomedical Literature Database (1978 to March 15, 2015) were searched to identify relevant trials. Only trials that compared radiofrequency ablation and liver resection for single very early stage (≤2 cm) or early stage (≤3 cm) HCC according to the Barcelona clinic liver cancer (BCLC) staging system were considered for inclusion in this review. The primary outcomes that we analyzed were the 3-year and 5-year overall survival (OS) rates, and the secondary outcomes that we analyzed were the 3-year and 5-year disease-free survival (DFS) rates. Review Manager 5.3 was used to perform a cumulative meta-analysis. Possible publication bias was examined using a funnel plot. A random-effects model was applied to summarize the various outcomes. Results Six studies involving 947 patients were identified that compared radiofrequency ablation (n=528) to liver resection (n=419) for single BCLC very early HCC. In these six studies, the rates of 3-year OS, 5-year OS, 3-year DFS, and 5-year DFS were significantly lower in the radiofrequency ablation group than in the liver resection group (risk ratio [RR] =0.90, 95% confidence interval [CI]: 0.83–0.98, P=0.01; RR =0.84, 95% CI: 0.75–0.95, P=0.004; RR =0.77, 95% CI: 0.60–0.98, P=0.04; and RR =0.70, 95% CI: 0.52–0.94, P=0.02, respectively). Ten studies involving 2,501 patients were identified that compared radiofrequency ablation (n=1,476) to liver resection (n=1,025) for single BCLC early HCC. In these ten studies, the rates of 3-year OS, 5-year OS, 3-year DFS, and 5-year DFS were also significantly lower in the radiofrequency ablation group than in the liver resection group (RR =0.93, 95% CI: 0.88–0

  19. Clinical Features of Acute Massive Pulmonary Embolism Complicated by Radiofrequency Ablation

    PubMed Central

    Li, Yue-Chun; Lin, Jiafeng; Wu, Lianpin; Li, Jia; Chen, Peng; Guang, Xue-Qiang

    2015-01-01

    Abstract Although pulmonary embolism (PE) complicated by radiofrequency catheter ablation (RFCA) is rare, it can be life-threatening. Our goal was to elucidate the clinical features of acute massive PE after RFCA. Of 2386 patients who underwent RFCA for supraventricular tachycardia or idiopathic ventricular arrhythmia, 4 patients (0.16%) whose cases were complicated by acute massive PE were examined. These 4 patients were female and middle-aged (range 43–52 years), and 2 of the 4 patients had iron-deficiency anemia and reactive thrombocytosis. Ablation in all patients was performed in the left heart via the right femoral arterial approach. All of the patients had a long-duration hemostasis procedure and bed rest following femoral arterial sheath removal after RFCA. All of the patients collapsed and lost consciousness during their first attempt at walking after RFCA. The emergent electrocardiogram in 2 of the 4 patients revealed an S1Q3T3 pattern, 1 patient demonstrated new onset of right bundle-branch block (RBBB) and S1Q3 pattern and Qr pattern in V1, and the remaining patient had negative T waves in leads V1, V2, and III. The emergent echocardiogram revealed right ventricular hypokinesis and pulmonary hypertension in the 4 patients with acute PE after ablation. Although all of the patients initially experienced sinus tachycardia when they recovered consciousness, 2 of the 4 patients suddenly developed intense bradycardia and lost consciousness again, and these patients finally died (50% fatality rate). All of the patients were identified by CT pulmonary angiography or pulmonary angiography. Our report suggests that although acute massive PE is highly rare, there is a real and fatal risk in patients who experienced acute massive PE after RFCA. Particular attention should be paid to the first ambulation after RFCA. Acute PE should be strongly suspected when sudden loss of consciousness occurs upon mobilization after RFCA. The new onset of S1Q3T3 pattern, RBBB

  20. Clinical Features of Acute Massive Pulmonary Embolism Complicated by Radiofrequency Ablation: An Observational Study.

    PubMed

    Li, Yue-Chun; Lin, Jiafeng; Wu, Lianpin; Li, Jia; Chen, Peng; Guang, Xue-Qiang

    2015-10-01

    Although pulmonary embolism (PE) complicated by radiofrequency catheter ablation (RFCA) is rare, it can be life-threatening. Our goal was to elucidate the clinical features of acute massive PE after RFCA. Of 2386 patients who underwent RFCA for supraventricular tachycardia or idiopathic ventricular arrhythmia, 4 patients (0.16%) whose cases were complicated by acute massive PE were examined. These 4 patients were female and middle-aged (range 43-52 years), and 2 of the 4 patients had iron-deficiency anemia and reactive thrombocytosis. Ablation in all patients was performed in the left heart via the right femoral arterial approach. All of the patients had a long-duration hemostasis procedure and bed rest following femoral arterial sheath removal after RFCA. All of the patients collapsed and lost consciousness during their first attempt at walking after RFCA. The emergent electrocardiogram in 2 of the 4 patients revealed an S1Q3T3 pattern, 1 patient demonstrated new onset of right bundle-branch block (RBBB) and S1Q3 pattern and Qr pattern in V1, and the remaining patient had negative T waves in leads V1, V2, and III. The emergent echocardiogram revealed right ventricular hypokinesis and pulmonary hypertension in the 4 patients with acute PE after ablation. Although all of the patients initially experienced sinus tachycardia when they recovered consciousness, 2 of the 4 patients suddenly developed intense bradycardia and lost consciousness again, and these patients finally died (50% fatality rate). All of the patients were identified by CT pulmonary angiography or pulmonary angiography. Our report suggests that although acute massive PE is highly rare, there is a real and fatal risk in patients who experienced acute massive PE after RFCA. Particular attention should be paid to the first ambulation after RFCA. Acute PE should be strongly suspected when sudden loss of consciousness occurs upon mobilization after RFCA. The new onset of S1Q3T3 pattern, RBBB or T

  1. Creation of a Tumor-Mimic Model Using a Muscle Paste for Radiofrequency Ablation of the Lung

    SciTech Connect

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

    2009-03-15

    The purpose of this study was to develop an easily created tumor-mimic model and evaluate its efficacy for radiofrequency ablation (RFA) of the lung. The bilateral lungs of eight living adult swine were used. A tumor-mimic model was made by percutaneous injection of 1.0 ml muscle paste through the bone biopsy needle into the lung. An RFA probe was then inserted into the tumor mimics immediately after tumor creation. Ablation time, tissue impedance, and temperature were recorded. The tumor mimics and their coagulated regions were evaluated microscopically and macroscopically. The muscle paste was easily injected into the lung parenchyma through the bone biopsy needle and well visualized under fluoroscopy. In 10 of 12 sites the tumor mimics were oval shaped, localized, and homogeneous on gross specimens. Ten tumor mimics were successfully ablated, and four locations were ablated in the normal lung parenchyma as controls. In the tumor and normal lung parenchyma, ablation times were 8.9 {+-} 3.5 and 4.4 {+-} 1.6 min, respectively; tissue impedances at the start of ablation were 100.6 {+-} 16.6 and 145.8 {+-} 26.8 {Omega}, respectively; and temperatures at the end of ablation were 66.0 {+-} 7.9 and 57.5 {+-} 7.6{sup o}C, respectively. The mean size of tumor mimics was 13.9 x 8.2 mm, and their coagulated area was 18.8 x 13.1 mm. In the lung parenchyma, the coagulated area was 15.3 x 12.0 mm. In conclusion, our tumor-mimic model using muscle paste can be easily and safely created and can be ablated using the ablation algorithm in the clinical setting.

  2. Monitoring Radiofrequency Ablation Using Ultrasound Envelope Statistics and Shear Wave Elastography in the Periablation Period: An In Vitro Feasibility Study.

    PubMed

    Tsui, Po-Hsiang; Wang, Chiao-Yin; Zhou, Zhuhuang; Wan, Yung-Liang

    2016-01-01

    Radiofrequency ablation (RFA) is a minimally invasive method for treating tumors. Shear wave elastography (SWE) has been widely applied in evaluating tissue stiffness and final ablation size after RFA. However, the usefulness of periablation SWE imaging in assessing RFA remains unclear. Therefore, this study investigated the correlation between periablation SWE imaging and final ablation size. An in vitro porcine liver model was used for experimental validation (n = 36). During RFA with a power of 50 W, SWE images were collected using a clinical ultrasound system. To evaluate the effects of tissue temperature and gas bubbles during RFA, changes in the ablation temperature were recorded, and image echo patterns were measured using B-mode and ultrasound statistical parametric images. After RFA, the gross pathology of each tissue sample was compared with the region of change in the corresponding periablation SWE image. The experimental results showed that the tissue temperature at the ablation site varied between 70°C and 100°C. Hyperechoic regions and changes were observed in the echo amplitude distribution induced by gas bubbles. Under this condition, the confounding effects (including the temperature increase, tissue stiffness increase, and presence of gas bubbles) resulted in artifacts in the periablation SWE images, and the corresponding region correlated with the estimated final ablation size obtained from the gross pathology (r = 0.8). The findings confirm the feasibility of using periablation SWE imaging in assessing RFA. PMID:27603012

  3. Irreversible Electroporation versus Radiofrequency Ablation: A Comparison of Local and Systemic Effects in a Small-Animal Model.

    PubMed

    Bulvik, Baruch E; Rozenblum, Nir; Gourevich, Svetlana; Ahmed, Muneeb; Andriyanov, Alexander V; Galun, Eithan; Goldberg, S Nahum

    2016-08-01

    Purpose To compare both periablational and systemic effects of two mechanistically different types of ablation: thermal radiofrequency (RF) ablation and electroporative ablation with irreversible electroporation (IRE) in appropriately selected animal models. Materials and Methods Animal experiments were performed according to a protocol approved by the Animal Care Committee of Hebrew University. Female C57BL/6 mice (n = 165) were randomized to undergo either RF or IRE ablation of noncancerous normal liver. The inflammatory response, cell proliferation, interleukin 6 (IL-6) levels, and intactness of vessels in the liver were assessed at 6, 12, and 24 hours and at 3, 7, and 14 days after ablation (n = 122 for mechanistic experiments). Systemic effects were then assessed by comparing tumor formation in an Mdr2-knockout (KO) mouse model (n = 15) and tumor growth in a remote BNL 1ME hepatoma xenograft tumor (n = 28). Results were averaged and evaluated by using two-tailed t tests. Results Although RF ablation was associated with a well-defined periablational inflammatory rim, for IRE, the infiltrate penetrated the ablation zone, largely along persistently patent vessels. Peak IL-6 levels (6 hours after ablation) were 10 and three times higher than at baseline for IRE and RF, respectively (P < .03). Mdr2-KO mice that were treated with IRE ablation had more tumors that were 3 mm or larger than mice treated with RF ablation or sham operation (mean, 3.6 ± 1.3 [standard deviation] vs 2.4 ± 1.1 and 2.2 ± 0.8, respectively; P < .05 for IRE vs both RF ablation and sham operation). For BNL 1ME tumors, both RF and IRE liver ablation reduced tumor growth, with a greater effect noted for IRE (1329 mm(3) ± 586 and 819 mm(3) ± 327 vs 2241 mm(3) ± 548 for sham operation; P < .05) that was accompanied by more infiltrating lymphocytes compared with sham operation (7.6 cells per frame ± 1.9 vs 11.2 ± 2.1 vs 0.3 ± 0.1; P < .05). Conclusion Persistent patency of vasculature within

  4. Clinical studies of the treatment of facial atrophic acne scars and acne with a bipolar fractional radiofrequency system.

    PubMed

    Kaminaka, Chikako; Uede, Mikiko; Matsunaka, Hiroshi; Furukawa, Fukumi; Yamamoto, Yuki

    2015-06-01

    Few clinical studies have examined the utility of bipolar fractional radiofrequency (FRF) therapy as a treatment for atrophic acne scars and active acne in people with darker skin. This study was designed to compare the safety and efficacy of bipolar FRF therapy as a treatment for atrophic acne scars and acne vulgaris. Twenty-three Japanese patients with atrophic acne scars and mild to severe acne on both cheeks were treated with a bipolar FRF system (eMatrix; Syneron, Yokneam Illit, Israel). Five treatment sessions were carried out at 1-month intervals, and the patients were followed up for 3 months after the final treatment. Assessments of scar severity and the number of acne lesions and 3-D in vivo imaging analysis were performed. Evaluations of the treatment outcomes and their effects on the patients' quality of life (QOL) were also carried out. We demonstrated that the improvement in scar volume was marked in the patients with mild scars and was at least moderate in 23 (57.5%) of the treated areas. With regard to the number of acne lesions, the treated areas exhibited significantly fewer lesions compared with the baseline at each time point (P < 0.05). The patients' assessments of the treatment outcomes and their QOL indicated that both had improved significantly by the end of the study. Furthermore, significant reductions in the patients' sebum levels, skin roughness and scar depth were observed. Bipolar FRF treatment significantly improved the atrophic acne scars and acne of Japanese patients and had minimal side-effects. PMID:25855397

  5. Fluoroscopic-guided radiofrequency ablation of the basivertebral nerve: application and analysis with multiple imaging modalities in an ovine model (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Bergeron, Jeffrey A.; Eskey, Cliff J.; Attawia, Mohammed; Patel, Samit J.; Ryan, Thomas P.; Pellegrino, Richard; Sutton, Jeffrey; Crombie, John; Paul, B. T.; Hoopes, P. J.

    2005-04-01

    Pathologic involvement of the basivertebral nerve, an intraosseous vertebral nerve found in humans and most mammalian species, may play a role in some forms of back pain. This study was designed to assess the feasibility and effects of the percutaneous delivery of radiofrequency (RF) energy to thermally ablate the basivertebral nerve in the lumbar vertebrae of mature sheep. Using fluoroscopic guidance, a RF bipolar device was placed and a thermal dose delivered to lumbar vertebral bodies in sheep. Post-treatment assessment included multiple magnetic resonance imaging (MRI) techniques and computed tomography (CT). These data were analyzed and correlated to histopathology and morphometry findings to describe the cellular and boney structural changes resulting from the treatment. Imaging modalities MRI and CT can be implemented to non-invasively describe treatment region and volume, marrow cellular effects, and bone density alterations immediately following RF treatment and during convalescence. Such imaging can be utilized to assess treatment effects and refine the thermal dose to vertebral body volume ratio used in treatment planning. This information will be used to improve the therapeutic ratio and develop a treatment protocol for human applications.

  6. The proposed use of radiofrequency ablation for the treatment of fistula-in-ano.

    PubMed

    Keogh, Kenneth M; Smart, Neil J

    2016-01-01

    Fistula in ano is a very common presentation to colorectal clinic. Embarrassment due to the symptoms makes accurate estimations of incidence difficult. It is estimated that up to 40% of peri-anal abscess will be accompanied by or preceded by a fistula. Fistulae can be classified into simple fistulae that involve no or minimal sphincter muscle and complex, which involve significant amounts of the anal sphincter muscle, possibly with multiple tracts. For complex fistulae a seton suture is usually placed through the tract and out through the anus to form a loop allowing pockets of sepsis to drain internally and externally and a mature tract of fibrous tissue to develop. Following this period definitive fistula treatment is considered. This can involve a number of procedures that have tremendously varied success rates in the literature. The first stage of surgical treatment is often a core fistulectomy, which entails surgical removal of the tract. This may be followed by insertion of fibrin glue, a collagen plug or formation of a rotation skin flap from surrounding tissue in order to close the resultant tissue defect. All current treatments have a significant failure rate. If this wound breaks down the surgery can leave a large painful peri-anal wound that can lead to ongoing fistulation. Should this occur resiting of the seton will be required with the patient only getting back to square one after months of healing around the seton. In addition removing cores of fibrous tissue passing through the sphincter can threaten the sphincter function resulting in impaired continence. Having seen radiofrequency ablation used to close varicose veins the authors propose that one could use similar techniques to close a fibrous tract matured with a seton in order to close a fistula. The authors propose that a short length radiofrequency catheter could be used to treat fistula in ano. This would in theory be less painful with less tissue destruction. In addition there would be no

  7. Comparison of fractional microneedling radiofrequency and bipolar radiofrequency on acne and acne scar and investigation of mechanism: comparative randomized controlled clinical trial.

    PubMed

    Min, Seonguk; Park, Seon Yong; Yoon, Ji Young; Suh, Dae Hun

    2015-12-01

    Fractional microneedling radiofrequency (FMR) is one of the promising methods in acne treatment. Moreover, bipolar radiofrequency (BR) generates heat thereby which induces neocollagenosis. FMR may have the potential to be a safe and effective treatment for the patients both with acne and acne scar. This study was performed to compare the efficacy and safety of FMR and BR in acne and acne scar treatment. Furthermore, mechanism of the FMR treatment was investigated through skin tissues obtained from subjects. Twenty subjects with mild-to-moderate acne and acne scars were treated in a split-face manner with FMR and BR. Two sessions of treatment was done 4 weeks apart in a total 12-week prospective single-blind, randomized clinical trial. Clinical assessment and sebum measurement were carried out for the evaluation of efficacy and safety. Skin tissues were acquired for investigation of molecular changes. FMR was more effective for acne scar especially in icepick and boxcar scar compared to BR. Both inflammatory and non-inflammatory acne lesions decreased by 80 and 65 % in the FMR-treated side at the final visit of 12 weeks, respectively. FMR treatment resulted in significant reduction of sebum excretion. Both treatments showed no severe adverse effects other than erythema. The FMR showed superior efficacy in acne and acne scar compared with BR. Increased expression of TGFβ and collagen I and decreased expression of NF-κB, IL-8 are suggested to involve in the improvement of acne scar and acne lesion by FMR. PMID:26472097

  8. Frequency and Risk Factors of Various Complications After Computed Tomography-Guided Radiofrequency Ablation of Lung Tumors

    SciTech Connect

    Okuma, Tomohisa Matsuoka, Toshiyuki; Yamamoto, Akira; Oyama, Yoshimasa; Toyoshima, Masami; Nakamura, Kenji; Inoue, Yuichi

    2008-01-15

    Objective. To retrospectively determine the frequency and risk factors of various side effects and complications after percutaneous computed tomography-guided radiofrequency (RF) ablation of lung tumors. Methods. We reviewed and analyzed records of 112 treatment sessions in 57 of our patients (45 men and 12 women) with unresectable lung tumors treated by ablation. Risk factors, including sex, age, tumor diameter, tumor location, history of surgery, presence of pulmonary emphysema, electrode gauge, array diameter, patient position, maximum power output, ablation time, and minimum impedance during ablation, were analyzed using univariate and multivariate analyses. Results. Total rates of side effects and minor and major complications occurred in 17%, 50%, and 8% of treatment sessions, respectively. Side effects, including pain during ablation (46% of sessions) and pleural effusion (13% of sessions), occurred with RF ablation. Minor complications, including pneumothorax not requiring chest tube drainage (30% of sessions), subcutaneous emphysema (16% of sessions), and hemoptysis (9% of sessions) also occurred after the procedure. Regarding major complications, three patients developed fever >38.5 deg. C; three patients developed abscesses; two patients developed pneumothorax requiring chest tube insertion; and one patient had air embolism and was discharged without neurologic deficit. Univariate and multivariate analyses suggested that a lesion located {<=}1 cm of the chest wall was significantly related to pain (p < 0.01, hazard index 5.76). Risk factors for pneumothorax increased significantly with previous pulmonary surgery (p < 0.05, hazard index 6.1) and presence of emphysema (p <0.01, hazard index 13.6). Conclusion. The total complication rate for all treatment sessions was 58%, and 25% of patients did not have any complications after RF ablation. Although major complications can occur, RF ablation of lung tumors can be considered a safe and minimally invasive

  9. Combination of Superselective Arterial Embolization and Radiofrequency Ablation for the Treatment of a Giant Renal Angiomyolipoma Complicated with Caval Thrombus

    PubMed Central

    Stamatiou, Konstantinos N.; Moschouris, Hippocrates; Marmaridou, Kiriaki; Kiltenis, Michail; Kladis-Kalentzis, Konstantinos; Malagari, Katerina

    2016-01-01

    This is a case of a 78-year-old male patient with multiple angiomyolipomas of a solitary right kidney. The largest of these tumors (maximum diameter: 13.4 cm) caused significant extrinsic compression of the inferior vena cava complicated by thrombosis of this vessel. Treatment of thrombosis with anticoagulants had been ineffective and the patient had experienced a bleeding episode from the largest right renal angiomyolipoma, which had been treated by transarterial embolization in another institution, 4 months prior to our intervention. Our approach included superselective transarterial embolization of the dominant, right kidney angiomyolipoma with hydrogel microspheres, which was combined, 20 days later, with ultrasonographically guided radiofrequency ablation. Both interventions were uneventful. Computed tomography 2 months after ablation showed a 53% reduction in tumor volume, reduced space-occupying effect on inferior vena cava, and resolution of caval thrombus. Nine months after intervention the patient has had no recurrence of thrombosis or hemorrhage and no tumor regrowth has been observed. The combination of superselective transarterial embolization and radiofrequency ablation seems to be a feasible, safe, and efficient treatment of large renal angiomyolipomas. PMID:27293932

  10. Combination of Superselective Arterial Embolization and Radiofrequency Ablation for the Treatment of a Giant Renal Angiomyolipoma Complicated with Caval Thrombus.

    PubMed

    Stamatiou, Konstantinos N; Moschouris, Hippocrates; Marmaridou, Kiriaki; Kiltenis, Michail; Kladis-Kalentzis, Konstantinos; Malagari, Katerina

    2016-01-01

    This is a case of a 78-year-old male patient with multiple angiomyolipomas of a solitary right kidney. The largest of these tumors (maximum diameter: 13.4 cm) caused significant extrinsic compression of the inferior vena cava complicated by thrombosis of this vessel. Treatment of thrombosis with anticoagulants had been ineffective and the patient had experienced a bleeding episode from the largest right renal angiomyolipoma, which had been treated by transarterial embolization in another institution, 4 months prior to our intervention. Our approach included superselective transarterial embolization of the dominant, right kidney angiomyolipoma with hydrogel microspheres, which was combined, 20 days later, with ultrasonographically guided radiofrequency ablation. Both interventions were uneventful. Computed tomography 2 months after ablation showed a 53% reduction in tumor volume, reduced space-occupying effect on inferior vena cava, and resolution of caval thrombus. Nine months after intervention the patient has had no recurrence of thrombosis or hemorrhage and no tumor regrowth has been observed. The combination of superselective transarterial embolization and radiofrequency ablation seems to be a feasible, safe, and efficient treatment of large renal angiomyolipomas. PMID:27293932

  11. Sampling modulation technique in radio-frequency helium glow discharge emission source by use of pulsed laser ablation.

    PubMed

    Naeem, Tariq Mahmood; Matsuta, Hideyuki; Wagatsuma, Kazuaki

    2004-05-01

    An emission excitation source comprising a high-frequency diode-pumped Q-switched Nd:YAG laser and a radio-frequency powered glow discharge lamp is proposed. In this system sample atoms ablated by the laser irradiation are introduced into the lamp chamber and subsequently excited by the helium glow discharge plasma. The pulsed operation of the laser can produce a cyclic variation in the emission intensities of the sample atoms whereas the plasma gas species emit the radiation continuously. The salient feature of the proposed technique is the selective detection of the laser modulation signal from the rest of the continuous background emissions, which can be achieved with the phase sensitive detection of the lock-in amplifier. The arrangement may be used to estimate the emission intensity of the laser ablated atom, free from the interference of other species present in the plasma. The experiments were conducted with a 13.56 MHz radio-frequency (rf) generator operated at 80 W power to produce plasma and the laser at a wavelength of 1064 nm (pulse duration:34 ns, repetition rate:7 kHz and average pulse energy of about 0.36 mJ) was employed for sample ablation. The measurements resulted in almost complete removal of nitrogen molecular bands (N(2)(+) 391.44 nm). Considerable reduction (about 75%) in the emission intensity of a carbon atomic line (C I 193.03 nm) was also observed. PMID:15034707

  12. Frequency of and Predictive Factors for Vascular Invasion after Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Asaoka, Yoshinari; Tateishi, Ryosuke; Nakagomi, Ryo; Kondo, Mayuko; Fujiwara, Naoto; Minami, Tatsuya; Sato, Masaya; Uchino, Koji; Enooku, Kenichiro; Nakagawa, Hayato; Kondo, Yuji; Shiina, Shuichiro; Yoshida, Haruhiko; Koike, Kazuhiko

    2014-01-01

    Background Vascular invasion in patients with hepatocellular carcinoma (HCC) is representative of advanced disease with an extremely poor prognosis. The detailed course of its development has not been fully elucidated. Methods We enrolled 1057 consecutive patients with HCC who had been treated with curative intent by radiofrequency ablation (RFA) as an initial therapy from 1999 to 2008 at our department. We analyzed the incidence rate of and predictive factors for vascular invasion. The survival rate after detection of vascular invasion was also analyzed. Results During a mean follow-up period of 4.5 years, 6075 nodules including primary and recurrent lesions were treated by RFA. Vascular invasion was observed in 97 patients. The rate of vascular invasion associated with site of original RFA procedure was 0.66% on a nodule basis. The incidence rates of vascular invasion on a patient basis at 1, 3, and 5 years were 1.1%, 5.9%, and 10.4%, respectively. Univariate analysis revealed that tumor size, tumor number, alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin (DCP), and Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein were significant risk predictors of vascular invasion. In multivariate analysis, DCP was the most significant predictor for vascular invasion (compared with a DCP of ≤100 mAu/mL, the hazard ratio was 1.95 when DCP was 101–200 mAu/mL and 3.22 when DCP was >200 mAu/mL). The median survival time after development of vascular invasion was only 6 months. Conclusion Vascular invasion occurs during the clinical course of patients initially treated with curative intent. High-risk patients may be identified using tumor markers. PMID:25397677

  13. Catheter-based radiofrequency renal-nerve ablation in patients with resistant hypertension.

    PubMed

    Azizi, M; Steichen, O; Frank, M; Bobrie, G; Plouin, P-F; Sapoval, M

    2012-03-01

    This review aims to describe the role and the results of catheter-based renal nerve ablation for the treatment of resistant hypertension. Despite the availability of multiple classes of orally active antihypertensive treatments, resistant hypertension remains an important public health issue in 2012 due to its prevalence and association with target-organ damage and poor prognosis. The failure of purely pharmacological approaches to treat resistant hypertension has stimulated interest in invasive device-based treatments based on old concepts. In the absence of orally active antihypertensive agents, patients with severe and complicated hypertension were widely treated by surgical denervation of the kidney until the 1960s, but this approach was associated with a high incidence of severe adverse events and a high mortality rate. A new catheter system using radiofrequency energy has been developed, allowing an endovascular approach to renal denervation and providing patients with resistant hypertension with a new therapeutic option that is less invasive than surgery and can be performed rapidly under local anaesthesia. To date, this technique has been evaluated only in open-label trials including small numbers of highly selected resistant hypertensive patients with suitable renal artery anatomy. The available evidence suggests a favourable blood pressure-lowering effect in the short term (6 months) and a low incidence of immediate local and endovascular complications. This follow-up period is, however, too short for the detection of rare or late-onset adverse events. For the time being, the benefit/risk ratio of this technique remains to be evaluated, precluding its uncontrolled and widespread use in routine practice. PMID:22237510

  14. Single hepatocellular carcinoma ≤ 3 cm in left lateral segment: Liver resection or radiofrequency ablation?

    PubMed Central

    Kim, Jong Man; Kang, Tae Wook; Kwon, Choon Hyuck David; Joh, Jae-Won; Ko, Justin Sangwook; Park, Jae Berm; Rhim, Hyunchul; Lee, Joon Hyeok; Kim, Sung Joo; Paik, Seung Woon

    2014-01-01

    AIM: To evaluate the long-term results of radiofrequency ablation (RFA) compared to left lateral sectionectomy (LLS) in patients with Child-Pugh class A disease for the treatment of single and small hepatocellular carcinoma (HCC) in the left lateral segments. METHODS: We retrospectively reviewed the data of 133 patients with single HCC (≤ 3 cm) in their left lateral segments who underwent curative LLS (n = 66) or RFA (n = 67) between 2006 and 2010. RESULTS: The median follow-up period was 33.5 mo in the LLS group and 29 mo in the RFA group (P = 0.060). Most patients had hepatitis B virus-related HCC. The hospital stay was longer in the LLS group than in the RFA group (8 d vs 2 d, P < 0.001). The 1-, 2-, and 3-year disease-free survival and overall survival rates were 80.0%, 68.2%, and 60.0%, and 95.4%, 92.3%, and 92.3%, respectively, for the LLS group; and 80.8%, 59.9%, and 39.6%, and 98.2%, 92.0%, and 74.4%, respectively, for the RFA group. The disease-free survival curve and overall survival curve were higher in the LLS group than in the RFA group (P = 0.012 and P = 0.013, respectively). Increased PIVKA-II levels and small tumor size were associated with HCC recurrence in multivariate analysis. CONCLUSION: Liver resection is suitable for single HCC ≤ 3 cm in the left lateral segments. PMID:24744596

  15. Radiofrequency Ablation of Small Hepatocellular Carcinoma in Cirrhotic Patients Awaiting Liver Transplantation

    PubMed Central

    Mazzaferro, Vincenzo; Battiston, Carlo; Perrone, Stefano; Pulvirenti, Andrea; Regalia, Enrico; Romito, Raffaele; Sarli, Dario; Schiavo, Marcello; Garbagnati, Francesco; Marchianò, Alfonso; Spreafico, Carlo; Camerini, Tiziana; Mariani, Luigi; Miceli, Rosalba; Andreola, Salvatore

    2004-01-01

    Objective: Determine the histologic response-rate (complete versus partial tumor extinction) after single radiofrequency ablation (RFA) of small hepatocellular carcinoma (HCC) arising in cirrhosis. Investigate possible predictors of response and assess efficacy and safety of RFA as a bridge to liver transplantation (OLT). Background: RFA has become the elective treatment of local control of HCC, although histologic data supporting radiologic assessment of response are rare and prospective studies are lacking. Prognostic impact of repeated RFA for HCC persistence is also undetermined. Methods: Percentage of RFA-induced necrosis and tumor persistence-rate at various intervals from treatment was studied in 60 HCC (median: 3 cm; Milan-Criteria IN: 80%) isolated in 50 consecutive cirrhotic patients undergoing OLT. Single-session RFA was the only treatment planned before OLT. Histologic response determined on explanted livers was related to 28 variables and to pre-OLT CT scan. Results: Mean interval RFA→OLT was 9.5 months. Post-RFA complete response rate was 55%, rising to 63% for HCC ≤3 cm. Tumor size was the only prognostic factor significantly related to response (P = 0.007). Tumor satellites and/or new HCC foci (56 nodules) were unaffected by RFA and significantly correlated with HCC >3 cm (P = 0.05). Post-RFA tumor persistence probability increased with time (12 months: 59%; 18 months: 70%). Radiologic response rate was 70%, not significantly different from histology. Major post-RFA morbidity was 8%. No mortality, Child deterioration, patient withdrawal because of tumor progression was observed. Post-OLT 3-year patient/graft survival was 83%. Conclusions: RFA is a safe and effective treatment of small HCC in cirrhotics awaiting OLT, although tumor size (>3 cm) and time from treatment (>1 year) predict a high risk of tumor persistence in the targeted nodule. RFA should not be considered an independent therapy for HCC. PMID:15492574

  16. Pain Analysis in Patients with Hepatocellular Carcinoma: Irreversible Electroporation versus Radiofrequency Ablation-Initial Observations

    SciTech Connect

    Narayanan, Govindarajan Froud, Tatiana; Lo, Kaming; Barbery, Katuska J. Perez-Rojas, Evelyn Yrizarry, Jose

    2013-02-15

    To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher's exact test, the Chi-square test, and Student's t test. There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

  17. Frequency, Risk Factors and Survival Associated with an Intrasubsegmental Recurrence after Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Tateishi, Ryosuke; Shiina, Shuichiro; Akahane, Masaaki; Sato, Jiro; Kondo, Yuji; Masuzaki, Ryota; Nakagawa, Hayato; Asaoka, Yoshinari; Goto, Tadashi; Otomo, Kuni; Omata, Masao; Yoshida, Haruhiko; Koike, Kazuhiko

    2013-01-01

    Background In the treatment of hepatocellular carcinoma (HCC), hepatic resection has the advantage over radiofrequency ablation (RFA) in terms of systematic removal of a hepatic segment. Methods We enrolled 303 consecutive patients of a single naïve HCC that had been treated by RFA at The University of Tokyo Hospital from 1999 to 2004. Recurrence was categorized as either intra- or extra-subsegmental as according to the Couinaud's segment of the original nodule. To assess the relationship between the subsegments of the original and recurrent nodules, we calculated the kappa coefficient. We assessed the risk factors for intra- and extra-subsegmental recurrence independently using univariate and multivariate Cox proportional hazard regression. We also assessed the impact of the mode of recurrence on the survival outcome. Results During the follow-up period, 201 patients in our cohort showed tumor recurrence distributed in a total of 340 subsegments. Recurrence was categorized as exclusively intra-subsegmental, exclusively extra-subsegmental, and simultaneously intra- and extra-subsegmental in 40 (20%), 110 (55%), and 51 (25%) patients, respectively. The kappa coefficient was measured at 0.135 (95% CI, 0.079–0.190; P<0.001). Multivariate analysis revealed that of the tumor size, AFP value and platelet count were all risk factors for both intra- and extra-subsegmental recurrence. Of the patients in whom recurrent HCC was found to be exclusively intra-subsegmental, extra-subsegmental, and simultaneously intra- and extra-subsegmental, 37 (92.5%), 99 (90.8%) and 42 (82.3%), respectively, were treated using RFA. The survival outcomes after recurrence were similar between patients with an exclusively intra- or extra-subsegmental recurrence. Conclusions The effectiveness of systematic subsegmentectomy may be limited in the patients with both HCC and chronic liver disease who frequently undergo multi-focal tumor recurrence. PMID:23593129

  18. Percutaneous Radiofrequency Ablation of Lung Cancer Presenting as Ground-Glass Opacity

    SciTech Connect

    Iguchi, Toshihiro Hiraki, Takao Gobara, Hideo Fujiwara, Hiroyasu Matsui, Yusuke; Soh, Junichi Toyooka, Shinichi; Kiura, Katsuyuki; Kanazawa, Susumu

    2015-04-15

    PurposeWe retrospectively evaluated the outcomes of lung cancer patients presenting with ground-glass opacity (GGO) who received radiofrequency ablation (RFA).MethodsSixteen patients (5 men and 11 women; mean age, 72.6 years) with 17 lung cancer lesions showing GGO (mean long axis diameter, 1.6 cm) underwent a total of 20 percutaneous computed tomography (CT) fluoroscopy-guided RFA sessions, including three repeated sessions for local progression. Lung cancer with GGO was defined as a histologically confirmed malignant pulmonary lesion with a GGO component accounting for >50 % of the lesion on high-resolution CT. Procedure outcomes were evaluated.ResultsThere were no major complications. Pneumothorax occurred in 15 of 20 treatment sessions: 14 were asymptomatic, and 1 required chest tube placement but resolved satisfactorily within 48 h. Minor pulmonary hemorrhage occurred in two and mild pneumonitis in one. The median tumor follow-up period was 61.5 (range 6.1–96.6) months. The effectiveness rates of the primary and secondary techniques were 100 and 100 % at 1 year, 93.3 and 100 % at 2 years, and 78.3 and 92.3 % at 3 years, respectively. The median patient follow-up period was 65.6 (range 6.1–96.6) months. One patient died owing to recurrent other cancer 11.7 months after RFA, whereas the other 15 remained alive. Overall survival and disease-specific survival rates were 93.3 and 100 % at 1 year and 93.3 and 100 % at 5 years, respectively.ConclusionsRFA for lung cancer with GGO was safe and effective, and resulted in promising survival rates.

  19. Radiofrequency ablation for chronic low back pain: A systematic review of randomized controlled trials

    PubMed Central

    Leggett, Laura E; Soril, Lesley JJ; Lorenzetti, Diane L; Noseworthy, Tom; Steadman, Rodney; Tiwana, Simrandeep; Clement, Fiona

    2014-01-01

    BACKGROUND: Radiofrequency ablation (RFA), a procedure using heat to interrupt pain signals in spinal nerves, is an emerging treatment option for chronic low back pain. Its clinical efficacy has not yet been established. OBJECTIVE: To determine the efficacy of RFA for chronic low back pain associated with lumbar facet joints, sacroiliac joints, discogenic low back pain and the coccyx. METHODS: A systematic review was conducted. Medline, EMBASE, PubMed, SPORTDiscus, CINAHL and the Cochrane Library were searched up to August 2013. Abstracts and full-text articles were reviewed in duplicate. Included articles were sham-controlled randomized controlled trials (RCTs), assessed the efficacy of RFA, reported at least one month of follow-up and included participants who had experienced back pain for at least three months. Data were extracted in duplicate and quality was assessed using the Cochrane Risk of Bias tool. Due to heterogeneity, as well as a lack of reported mean differences and SDs, meta-analysis was not possible using these data. RESULTS: The present systematic review retrieved 1063 abstracts. Eleven sham-controlled RCTs were included: three studies involving discogenic back pain; six studies involving lumbar facet joint pain; and two studies involving sacroiliac joint pain. No studies were identified assessing the coccyx. The evidence supports RFA as an efficacious treatment for lumbar facet joint and sacroiliac joint pain, with five of six and both of the RCTs demonstrating statistically significant pain reductions, respectively. The evidence supporting RFA for the treatment of discogenic pain is mixed. CONCLUSIONS: While the majority of the studies focusing on lumbar facet joints and sacroiliac joints suggest that RFA significantly reduces pain in short-term follow-up, the evidence base for discogenic low back pain is mixed. There is no RCT evidence for RFA for the coccyx. Future studies should examine the clinical significance of the achieved pain reduction

  20. Toward realistic radiofrequency ablation of hepatic tumors 3D simulation and planning

    NASA Astrophysics Data System (ADS)

    Villard, Caroline; Soler, Luc; Gangi, Afshin; Mutter, Didier; Marescaux, Jacques

    2004-05-01

    Radiofrequency ablation (RFA) has become an increasingly used technique in the treatment of patients with unresectable hepatic tumors. Evaluation of vascular architecture, post-RFA tissue necrosis prediction, and the choice of a suitable needle placement strategy using conventional radiological techniques remain difficult. In an attempt to enhance the safety of RFA, a 3D simulator and treatment planning tool, that simulates the necrosis of the treated area, and proposes an optimal placement for the needle, has been developed. From enhanced spiral CT scans with 2 mm cuts, 3D reconstructions of patients with liver metastases are automatically generated. Virtual needles can be added to the 3D scene, together with their corresponding zones of necrosis that are displayed as a meshed spheroids representing the 60° C isosurface. The simulator takes into account the cooling effect of local vessels greater than 3mm in diameter, making necrosis shapes more realistic. Using a voxel-based algorithm, RFA spheroids are deformed following the shape of the vessels, extended by an additional cooled area. This operation is performed in real-time, allowing updates while needle is adjusted. This allows to observe whether the considered needle placement strategy would burn the whole cancerous zone or not. Planned needle positioning can also be automatically generated by the software to produce complete destruction of the tumor with a 1 cm margin, with maximum respect of the healthy liver and of all major extrahepatic and intrahepatic structures to avoid. If he wishes, the radiologist can select on the skin an insertion window for the needle, focusing the research of the trajectory.

  1. Sorafenib in combination with transarterial chemoembolization and radiofrequency ablation in the treatment for unresectable hepatocellular carcinoma.

    PubMed

    Li, Yong; Zheng, You-Bing; Zhao, Wei; Liu, Bing; Hu, Bao-Shan; He, Xu; Huang, Jian-Wen; Lu, Li-Gong

    2013-12-01

    The purpose of this study is to assess clinical efficacy and safety of sorafenib combined with transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) on patients with unresectable hepatocellular carcinoma (HCC). Efficacy and safety profiles of sorafenib in combination with TACE and RFA were evaluated based on retrospective data for thirty patients with unresectable HCC. Patients were treated with TACE initially when admitted to hospital, followed by RFA 3 days after TACE. All TACE and RFA were performed by the same team of doctors. Seven days after the first TACE, patients started taking continuous sorafenib 400 mg bid without breaks until unacceptable toxicities or disease progression. The response to treatment, overall survival (OS), time to progression (TTP), and adverse effects were evaluated. The disease control rate was 33.3% by RECIST criteria. The median TTP was 15.3 months (95% CI 4.8-23.5). The median OS was 28.8 months (95% CI 12.8-39.6). At the time of data record, 13 patients (43.3%) were dead. Median OS in patients with or without portal vein thrombosis was 12.3 months (95% CI 7.6-14.5) and 30.2 months (95% CI 24.2-34.5), respectively, P = 0.018. The most common adverse events related to sorafenib were hand-foot skin reaction (53.3%) and diarrhea (33.3%). The combination of sorafenib, TACE, and RFA proved both safe and effective in the treatment for unresectable hepatocellular carcinoma patients. PMID:24048774

  2. Noninvasive Fibrosis Marker Can Predict Recurrence of Hepatocellular Carcinoma after Radiofrequency Ablation

    PubMed Central

    Chung, Hyun Ah; Kim, Jeong-Han; Hwang, Young; Choi, Hong Seok; Ko, Soon Young; Choe, Won Hyeok; Kwon, So Young

    2016-01-01

    Background/Aims: Tumor recurrence after curative therapy is common for patients with hepatocellular carcinoma (HCC). As fibrosis and chronic inflammation contribute to the progression of HCC, we aimed to identify the predictive value of inflammatory and fibrosis markers for HCC recurrence after curative therapy using radiofrequency ablation (RFA). Materials and Methods: We retrospectively reviewed the records of patients with HCC treated with RFA between October 2005 and September 2013. The median duration of follow-up was 40 months (4–95 months). Inflammatory and fibrosis markers and demographic and clinical data were analyzed by Cox proportional hazards model using univariate and multivariate analyses and longitudinal analysis. Results: A total of 98 patients were included for analysis. There were 54 cases of HCC recurrence (55.1%). The aspartate aminotransferase-to-platelet ratio index (APRI; 2.3 ± 1.8 vs. 1.3 ± 1.4, P = 0.018) was significantly higher in the recurrence group than in the recurrence-free group. In multivariate analysis, APRI (hazard ratio, 2.64; confidence interval, 1.488–4.714; P = 0.001) was an independent risk factor for tumor recurrence. In particular, patients with APRI >1.38 showed a higher recurrence rate than patients with APRI ≤1.38 (P < 0.001). Longitudinal analysis showed persistently higher APRI values when assessed 12 months after RFA in patients who developed recurrence during follow-up than those who remained recurrence-free. Conclusions: These findings show that a high APRI value is associated with HCC recurrence after RFA. Therefore, APRI could play an important role in predicting HCC recurrence after RFA. PMID:26831608

  3. Intraoperative radiofrequency ablation for hepatocellular carcinoma in 112 patients with cirrhosis: a surgeon's view

    PubMed Central

    Lee, Jung Yeon; Roh, Young Hoon; Roh, Kyung Bin; Kim, Kwan Woo; Kang, Sung Hwa; Baek, Yang Hyun; Lee, Sung Wook; Han, Sang Young; Kwon, Hee Jin; Cho, Jin Han

    2016-01-01

    Purpose This retrospective study was an investigation of overall survival (OS), disease-free survival (DFS) and prognostic factors affecting OS and DFS in cirrhotic patients who received intraoperative radiofrequency ablation (IORFA). Methods Between April 2009 and November 2013, 112 patients (94 men, 84%; 18 women, 16%) underwent IORFA for 185 cases of hepatocellular carcinomas (HCC). Repeat IORFA was done in 9 patients during the same period (total of 121 treatments). Results All patients were followed-up for at least 12 months (mean follow-up, 32 months). Surgical resection combined with IORFA was performed in 20 patients. The technical effectiveness at 1 week was 91.78% (111 of 121). Readmission was 9.1% (11 of 121) and the most common cause was ventral hernia. Procedure-related mortality was 2.7% (3 of 112) and continued fatal biliary leakage was 1.8% (2 of 112). Local recurrence developed in 10 patients (8.9%). Most recurrence was intrahepatic. Cumulative survival was assessed in 33 patients who received IORFA as primary treatment (naive patients) and 79 non-naive patients. The cumulative DFS and OS rate at l and 3 years was 54% and 24%, and 87% and 66%, respectively. Moderate ascites (P = 0.001), tumor located segment I (P = 0.001), portal vein thrombosis (P = 0.001) had poor survival were significant factors by multivariate analysis. Conclusion IORFA alone or in combination with surgical resection extends the spectrum of liver surgery. A fundamental understanding of RFA, additional comorbidities, and postablation complication are necessary to maximize the safety and efficacy of IORFA for treating HCC with cirrhosis. PMID:26942158

  4. Combination transarterial chemoembolization and radiofrequency ablation therapy for early hepatocellular carcinoma

    PubMed Central

    Song, Myeong Jun; Bae, Si Hyun; Lee, June Sung; Lee, Sung Won; Song, Do Seon; You, Chan Ran; Choi, Jong Young; Yoon, Seung Kew

    2016-01-01

    Background/Aims: We compared the recurrence of hepatocellular carcinoma (HCC) and the survival of patients who received radiofrequency ablation (RFA) after transarterial chemoembolization (TACE) with patients treated with TACE or RFA alone. Methods: This study included 201 patients with HCC, who were consecutively enrolled at Seoul St. Mary’s Hospital between December 2004 and February 2010. Inclusion criteria were a single HCC ≤ 5.0 cm or up to three HCCs ≤ 3.0 cm. We used a propensity score model to compare HCC patients (n = 87) who received RFA after TACE (TACE + RFA) with those who received TACE (n = 71) or RFA alone (n = 43). Results: The median follow-up period was 33.3 months (range, 6.8 to 80.9). The TACE + RFA group showed significantly lower local recurrence than the RFA or TACE groups (hazard ratio [HR], 0.309; 95% confidence interval [CI], 0.130 to 0.736; p = 0.008; and HR, 0.352; 95% CI, 0.158 to 0.787; p = 0.011, respectively). The overall survival was significantly better in the TACE + RFA group compared to the RFA group (HR, 0.422; 95% CI, 0.185 to 0.964; p = 0.041). However, the survival benefit was not different between the TACE + RFA and TACE groups (p = 0.124). Subgroup analysis showed that among patients with a tumor size < 3 cm, the TACE + RFA group had significantly better long-term survival than those in the TACE or RFA groups (p = 0.017, p = 0.004, respectively). Conclusions: TACE + RFA combination treatment showed favorable local recurrence and better overall survival rates in early-stage HCC patients. Patients with tumors < 3 cm are likely to benefit more from TACE + RFA combination treatment. Additional studies are needed for the selection of suitable HCC patients for TACE + RFA treatment. PMID:26874512

  5. Role of contrast-enhanced ultrasonography in percutaneous radiofrequency ablation of liver metastases and efficacy evaluation

    PubMed Central

    Wu, Jie; Yang, Wei; Yin, Shanshan; Wu, Jinyu; Wu, Wei; Yan, Kun

    2013-01-01

    Objective To retrospectively investigate the role of contrast-enhanced ultrasonography (CEUS) in percutaneous radiofrequency ablation (RFA) in patients with liver metastases and evaluate the therapeutic efficacy of RFA assisted by CEUS. Methods From May 2004 to September 2010, 136 patients with 219 liver metastatic lesions received CEUS examination 1 h before RFA (CEUS group), and other 126 patients with 216 lesions without CEUS examination in the earlier period were served as a historical control group. The mean tumor size was 3.2 cm and the mean tumor number was 1.6 in the CEUS group, while 3.4 cm and 1.7 in the control group, respectively (P>0.05). The clinical characteristics, recurrence results and survival outcomes were compared between two groups. Results In the CEUS group, two isoechoic tumors were not demonstrated on unenhanced ultrasonography (US), and 63 (47%) of 134 tumors examined with CEUS were 0.3 cm larger than with unenhanced US. Furthermore, in 18.4% of 136 patients, additional 1-3 tumors were detected on CEUS. The CEUS group showed higher early tumor necrosis and lower intrahepatic recurrence than the control group. The 3-year overall survival (OS) rate and the 3-year local recurrence-free survival (LRFS) rate in the CEUS group were 50.1% and 38.3%, in contrast to 25.3% and 19.3% in the control group, respectively (P=0.002 and P<0.001). Conclusions CEUS provides important information for RFA treatment in patients with liver metastases and better therapeutic effect could be attained. PMID:23592894

  6. Ultrasound-Guided Radiofrequency Thermal Ablation of Uterine Fibroids: Medium-Term Follow-Up

    SciTech Connect

    Carrafiello, Gianpaolo; Recaldini, Chiara Fontana, Federico; Ghezzi, Fabio; Cuffari, Salvatore; Lagana, Domenico; Fugazzola, Carlo

    2010-02-15

    Previous studies have shown that radiofrequency thermal ablation (RFA) of uterine fibroids through a percutaneous ultrasound (US)-guided procedure is an effective and safe minimally invasive treatment, with encouraging short-term results. The aim of this study was to assess the results in terms of volume reduction and clinical symptoms improvement in the midterm follow-up of fibroids with a diameter of up to 8 cm. Eleven premenopausal females affected by symptomatic fibroids underwent percutaneous US-guided RFA. Symptom severity and reduction in volume were evaluated at 1, 3, 6, 9, and 12 months. The mean symptom score (SSS) before the procedure was 50.30 (range 31.8-67.30), and the average quality of life (QOL) score value was 62 (range 37.20-86.00). The mean basal diameter was 5.5 cm (range 4.4-8) and the mean volume was 101.5 cm{sup 3} (range 44.58-278 cm{sup 3}). The mean follow-up was 9 months (range 3-12 months). The mean SSS value at the end of the follow-up was 13.38 (range 0-67.1) and the QOL 90.4 (range 43.8-100). At follow-up the mean diameter was 3.0 cm (range 1.20-4.5 cm), and the mean volume was 18 cm{sup 3} (range 0.90-47.6 cm{sup 3}). In 10 of 11 patients we obtained total or partial regression of symptoms. In one case the clinical manifestations persisted and it was thus considered unsuccessful. In conclusion, US-guided percutaneous RFA is a safe and effective treatment even for fibroids up to 8 cm.

  7. Percutaneous Vertebroplasty for Pain Management in Patients with Multiple Myeloma: Is Radiofrequency Ablation Necessary?

    SciTech Connect

    Orgera, Gianluigi; Krokidis, Miltiadis; Matteoli, Marco; Varano, Gianluca Maria; La Verde, Giacinto; David, Vincenzo; Rossi, Michele

    2013-05-08

    PurposeThis study was designed to investigate the added role of radiofrequency ablation (RFA) to vertebroplasty on the pain management of patients with multiple myeloma (MM).MethodsThirty-six patients (51–82 years) with vertebral localization of MM were randomly divided into two groups: 18 patients (group A) who underwent RFA and then vertebroplasty, and 18 patients (group B) who underwent only vertebroplasty. Primary endpoints were technical success and pain relief score rate measured by the visual analogue pain scores (VAS) and Roland–Morris Questionnaire (RMQ); secondary endpoint was the amount of administered analgesia. Survival and complications were compared.ResultsTechnical success was 100 % in both groups. The VAS score (at 24 h and 6 weeks postprocedure) decreased in equal manner for both groups from a mean of 9.1–3.4 and 2.0 for group A and from a mean of 9.3–3.0 and 2.3 for group B; RMQ mean score was 19.8 for group A and 19.9 for group B and decreased to a mean of 9.6 and 8.2 for group A and 9.5 and 8.7 for group B. The amount of medication was equally decreased in the two groups. No statistically significant difference was noted. No major complication occurred and two patients died from other causes.ConclusionsThe use of percutaneous vertebroplasty alone appears to be effective for the pain management of the patients with vertebral involvement of multiple myeloma. The use of RFA that includes cost and time does not offer any clear added benefit on the midterm pain management of such patients.

  8. Safety of Prior Endoscopic Mucosal Resection in Patients Receiving Radiofrequency Ablation of Barrett’s Esophagus

    PubMed Central

    Okoro, Ngozi I.; Tomizawa, Yutaka; Dunagan, Kelly T.; Lutzke, Lori S.; Wang, Kenneth K.; Prasad, Ganapathy A.

    2011-01-01

    BACKGROUND & AIMS Radiofrequency ablation (RFA) is safe and effective treatment for flat dysplasia associated with Barrett’s esophagus (BE). However, there are limited data on the safety of RFA in patients who had prior endoscopic mucosal resection (EMR), which might increase the risk of complications. We compared complications and histologic outcomes between patients who had EMR before RFA and those who received only RFA. METHODS We performed a retrospective analysis of data collected from patients treated for BE, associated with dysplasia or intramucosal cancer, at the Mayo Clinic in Rochester, Minnesota, from 1998–2009. Patients were divided into groups that had RFA after EMR (group 1, n = 44) or only RFA (group 2, n = 46). We compared the incidence of complications (strictures, bleeding, and esophageal perforation) and histologic features (complete resolution of dysplasia and complete resolution of intestinal metaplasia [CR-IM]) between groups. Logistic regression analysis was performed to assess predictors of stricture formation. RESULTS Stricture rates were 14% in group 1 and 9% in group 2 (odds ratio, 1.53; 95% confidence interval [CI], 0.26 –9.74). The rates of CR-IM were 43% in group 1 and 74% in group 2 (odds ratio, 0.33; 95% CI, 0.14 – 0.78). The rates of complete resolution of dysplasia were 76% in group 1 and 71% in group 2 (odds ratio, 1.28; 95% CI, 0.39 – 4.17). The adjusted odds ratio for CR-IM in group 1 (adjusting for age, segment length, and grade of dysplasia) was 0.50 (95% CI, 0.15–1.66). CONCLUSIONS Stricture rates among patients who receive only RFA are comparable to those of patients who had prior EMR. EMR appears safe to perform prior to RFA. PMID:22056303

  9. Induction of abortion following radiofrequency ablation of the endometrium: A case report and search for evidence-based practice.

    PubMed

    Khafizova, Lilia; Minas, Vasileios; Alam, M Ash

    2014-02-01

    OBJECTIVES Pregnancy following endometrial ablation is a rare event that carries significant risks to the mother. The majority of women elect to terminate such pregnancies. This brings into question which of the available methods should best be employed and what kinds of problems to anticipate. CASE We present a case of a pregnancy following radiofrequency endometrial ablation that was terminated surgically and review the relevant English literature. CONCLUSIONS Medical or surgical abortion can be considered as primary methods of terminating a first trimester intrauterine pregnancy following endometrial ablation. The choice will depend on patient preference but also on the available expertise. Cervical stenosis and/or intrauterine adhesions may limit the effectiveness of these methods. In such cases methotrexate is an alternative option, whereas hysterotomy or hysterectomy should be considered as final options. Counselling patients at the time of endometrial ablation regarding the need for contraception, even after prolonged periods of amenorrhoea is of paramount importance. Laparoscopic or hysteroscopic sterilisation can be offered together with endometrial ablation. PMID:24266730

  10. Limiting esophageal temperature in radiofrequency ablation of left atrial tachyarrhythmias results in low incidence of thermal esophageal lesions

    PubMed Central

    2010-01-01

    Background Atrio-esophageal fistula formation following radiofrequency ablation of left atrial tachyarrhythmias is a rare but devastating complication. Esophageal injuries are believed to be precursors of fistula formation and reported to occur in up to 47% of patients. This study investigates the incidence of esophageal lesions when real time esophageal temperature monitoring and temperature limitation is used. Methods 184 consecutive patients underwent open irrigated radiofrequency ablation of left atrial tachyarrhythmias. An esophageal temperature probe consisting of three independent thermocouples was used for temperature monitoring. A temperature limit of 40°C was defined to interrupt energy delivery. All patients underwent esophageal endoscopy the next day. Results Endoscopy revealed ulcer formation in 3/184 patients (1.6%). No patient developed atrio-esophageal fistula. Patient and disease characteristics had no influence on ulcer formation. The temperature threshold of 40°C was reached in 157/184 patients. A temperature overshoot after cessation of energy delivery was observed frequently. The mean maximal temperature was 40.8°C. Using a multiple regression analysis creating a box lesion that implies superior- and inferior lines at the posterior wall connecting the right and left encircling was an independent predictor of temperature. Six month follow-up showed an overall success rate of 78% documented as sinus rhythm in seven-day holter ECG. Conclusion Limitation of esophageal temperature to 40°C is associated with the lowest incidence of esophageal lesion formation published so far. This approach may contribute to increase the safety profile of radiofrequency ablation in the left atrium. PMID:20977747

  11. Percutaneous radiofrequency ablation for early hepatocellular carcinoma: Risk factors for survival

    PubMed Central

    Kikuchi, Luciana; Menezes, Marcos; Chagas, Aline L; Tani, Claudia M; Alencar, Regiane SSM; Diniz, Marcio A; Alves, Venâncio AF; D’Albuquerque, Luiz Augusto Carneiro; Carrilho, Flair José

    2014-01-01

    AIM: To evaluate outcomes of radiofrequency ablation (RFA) therapy for early hepatocellular carcinoma (HCC) and identify survival- and recurrence-related factors. METHODS: Consecutive patients diagnosed with early HCC by computed tomography (CT) or magnetic resonance imaging (MRI) (single nodule of ≤ 5 cm, or multi- (up to 3) nodules of ≤ 3 cm each) and who underwent RFA treatment with curative intent between January 2010 and August 2011 at the Instituto do Câncer do Estado de São Paulo, Brazil were enrolled in the study. RFA of the liver tumors (with 1.0 cm ablative margin) was carried out under CT-fluoro scan and ultrasonic image guidance of the percutaneous ablation probes. Procedure-related complications were recorded. At 1-mo post-RFA and 3-mo intervals thereafter, CT and MRI were performed to assess outcomes of complete response (absence of enhancing tissue at the tumor site) or incomplete response (enhancing tissue remaining at the tumor site). Overall survival and disease-free survival rates were estimated by the Kaplan-Meier method and compared by the log rank test or simple Cox regression. The effect of risk factors on survival was assessed by the Cox proportional hazard model. RESULTS: A total of 38 RFA sessions were performed during the study period on 34 patients (age in years: mean, 63 and range, 49-84). The mean follow-up time was 22 mo (range, 1-33). The study population showed predominance of male sex (76%), less severe liver disease (Child-Pugh A, n = 26; Child-Pugh B, n = 8), and single tumor (65%). The maximum tumor diameters ranged from 10 to 50 mm (median, 26 mm). The initial (immediately post-procedure) rate of RFA-induced complete tumor necrosis was 90%. The probability of achieving complete response was significantly greater in patients with a single nodule (vs patients with multi-nodules, P = 0.04). Two patients experienced major complications, including acute pulmonary edema (resolved with intervention) and intestinal perforation

  12. Histopomorphic Evaluation of Radiofrequency Mediated Débridement Chondroplasty

    PubMed Central

    Ganguly, Kumkum; McRury, Ian D; Goodwin, Peter M; Morgan, Roy E; Augé II, Wayne K

    2010-01-01

    The use of radiofrequency devices has become widespread for surgical ablation procedures. When ablation devices have been deployed in treatment settings requiring tissue preservation like débridement chondroplasty, adoption has been limited due to the collateral damage caused by these devices in healthy tissue surrounding the treatment site. Ex vivo radiofrequency mediated débridement chondroplasty was performed on osteochondral specimens demonstrating surface fibrillation obtained from patients undergoing knee total joint replacement. Three radiofrequency systems designed to perform débridement chondroplasty were tested each demonstrating different energy delivery methods: monopolar ablation, bipolar ablation, and non-ablation energy. Treatment outcomes were compared with control specimens as to clinical endpoint and histopomorphic characteristics. Fibrillated cartilage was removed in all specimens; however, the residual tissue remaining at the treatment site displayed significantly different characteristics attributable to radiofrequency energy delivery method. Systems that delivered ablation-based energies caused tissue necrosis and collateral damage at the treatment site including corruption of cartilage Superficial and Transitional Zones; whereas, the non-ablation system created a smooth articular surface with Superficial Zone maintenance and without chondrocyte death or tissue necrosis. The mechanism of radiofrequency energy deposition upon tissues is particularly important in treatment settings requiring tissue preservation. Ablation-based device systems can cause a worsened state of articular cartilage from that of pre-treatment. Non-ablation energy can be successful in modifying/preconditioning tissue during débridement chondroplasty without causing collateral damage. Utilizing a non-ablation radiofrequency system provides the ability to perform successful débridement chondroplasty without causing additional articular cartilage tissue damage and may

  13. Percutaneous Intraductal Radiofrequency Ablation Combined with Biliary Stent Placement for Nonresectable Malignant Biliary Obstruction Improves Stent Patency but not Survival

    PubMed Central

    Wang, Jianfeng; Zhao, Lizhen; Zhou, Chuanguo; Gao, Kun; Huang, Qiang; Wei, Baojie; Gao, Jun

    2016-01-01

    Abstract Although radiofrequency (RF) ablation has been accepted as a curative treatment modality for solid organ tumors, intraductal RF ablation for malignant biliary obstruction has not been widely described. The aim of this study was to evaluate the feasibility, safety, and efficacy (in terms of stent patency and survival) of intraductal RF ablation combined with biliary stent placement for nonresectable malignant biliary obstruction. A search of the nonresectable malignant extrahepatic biliary obstruction database (179 patients) identified 18 consecutive patients who were treated with biliary intraluminal RF ablation during percutaneous transhepatic cholangiodrainage and inner stent placement (RF ablation group) and 18 patients who underwent inner stent placement without biliary intraluminal RF ablation (control group). The patients were matched for tumor type, location of obstruction, tumor stage, and Child–Pugh class status. Primary endpoints included safety, stent patency time, and survival rates. The secondary endpoint was effectiveness of the technique. The RF ablation and control groups were closely matched in terms of age, diagnosis, presence of metastases, presence of locally advanced tumor, American Society of Anesthesiologists (ASA) grade, and chemotherapy regimen (all P > 0.05). The technical success rate for both groups was 100%. The median time of stent patency in the RF ablation and control groups were 5.8 (2.8–11.5) months and 4.5 (2.4–8.0) months, respectively (Kaplan–Meier analysis: P = 0.03). The median survival times in the RF ablation and control groups were 6.1 (4.8–15.2) months and 5.8 (4.2–16.5) months, with no significant difference according to Kaplan–Meier analysis (P = 0.45). In univariate and multivariate analyses, poorer overall survival was associated with advanced age and presence of metastases (P < 0.05). Intraductal RF ablation combined with biliary stent placement for nonresectable malignant

  14. Young’s Modulus Reconstruction for Radio-frequency Ablation Electrode-induced Displacement Fields: A Feasibility Study

    PubMed Central

    Jiang, Jingfeng; Varghese, Tomy; Brace, Chris L.; Madsen, Ernest L.; Hall, Timothy J.; Bharat, Shyam; Hobson, Maritza A.; Zagzebski, James A.; Lee, Fred T.

    2009-01-01

    Radiofrequency (RF) ablation is a minimally invasive treatment for tumors in various abdominal organs. It is effective if good tumor localization and intra-procedural monitoring can be done. In this paper, we investigate the feasibility of using an ultrasound-based Young’s modulus reconstruction algorithm to image an ablated region whose stiffness is elevated due to tissue coagulation. To obtain controllable tissue deformations for abdominal organs during and/or intermediately after the RF ablation, the proposed modulus imaging method is specifically designed for using tissue deformation fields induced by the RF electrode. We have developed a new scheme under which the reconstruction problem is simplified to a two-dimensional problem. Based on this scheme, an iterative Young’s modulus reconstruction technique with edge-preserving regularization was developed to estimate the Young’s modulus distribution. The method was tested in experiments using a tissue-mimicking phantom and on ex vivo bovine liver tissues. Our preliminary results suggest that high contrast modulus images can be successfully reconstructed. In both experiments, the geometries of the reconstructed modulus images of thermal ablation zones match well with the phantom design and the gross pathology image, respectively. PMID:19258195

  15. Sequential Activation of a Segmented Ground Pad Reduces Skin Heating During Radiofrequency Tumor Ablation: Optimization via Computational Models

    PubMed Central

    Schutt, David J.; Haemmerich, Dieter

    2009-01-01

    Radiofrequency (RF) ablation has become an accepted treatment modality for unresectable tumors. The need for larger ablation zones has resulted in increased RF generator power. Skin burns due to ground pad heating are increasingly limiting further increases in generator power, and thus, ablation zone size. We investigated a method for reducing ground pad heating in which a commercial ground pad is segmented into multiple ground electrodes, with sequential activation of ground electrode subsets. We created finite-element method computer models of a commercial ground pad (14 × 23 cm) and compared normal operation of a standard pad to sequential activation of a segmented pad (two to five separate ground electrode segments). A constant current of 1 A was applied for 12 min in all simulations. Time periods during sequential activation simulations were adjusted to keep the leading edge temperatures at each ground electrode equal. The maximum temperature using standard activation of the commercial pad was 41.7 °C. For sequential activation of a segmented pad, the maximum temperature ranged from 39.3 °C (five segments) to 40.9 °C (two segments). Sequential activation of a segmented ground pad resulted in lower tissue temperatures. This method may reduce the incidence of ground pad burns and enable the use of higher power generators during RF tumor ablation. PMID:18595807

  16. Heat-Irrigate Effect' of Radiofrequency Ablation on Relevant Regional Hepatocyte in Living Swine Liver-Initial Study on Pathology.

    PubMed

    Jiang, Kai; Chen, Jiye; Liu, Yang; Liu, Jiang; Liu, Aijun; Dong, Jiahong; Huang, Zhiqiang

    2015-05-01

    Radiofrequency ablation (RFA) is one of the effective methods for HCC treatment. However, because of the "heat-sink effect" (HSE), it is very difficult to achieve a complete ablation in intrahepatic tumors. This study establishes the animal model of RFA on living swine liver and observes the 'heat-irrigate effect' on relevant regional hepatocytes. Three liver segments of 6 Guangxi Bama mini-pigs were selected to be ablated closed to segmental outflow vessel under surveillance of sonography for 6 min, and pathological changes of relevant downstream region were observed. We observed an elliptic shape of ablated area with diameter of 2.2 ± 1.1 cm on gross liver. Thermal damage was seen in downstream regional of relevant portal vein under microscope. However, adjacent area around the vessel was remained intact. In conclusion, the 'heat-irrigate effect' in RFA could cause thermal damage along the downstream region of relevant portal vein and this influence decreased gradually toward the surface. PMID:25416583

  17. Computed Tomographic-Guided Radiofrequency Ablation of Recurrent or Residual Hepatocellular Carcinomas around Retained Iodized Oil after Transarterial Chemoembolization

    PubMed Central

    Koh, Young Hwan; Kim, Hyun Beom; Kim, Min Ju

    2013-01-01

    Objective To assess the clinical efficacy, safety, and risk factors influencing local tumor progression, following CT-guided radiofrequency ablation (RFA) of recurrent or residual hepatocellular carcinoma (HCC), around iodized oil retention. Materials and Methods Sixty-four patients (M : F = 51 : 13, 65.0 ± 8.2 years old) with recurrent or residual HCC (75 index tumors, size = 14.0 ± 4.6 mm) had been treated by CT-guided RFA, using retained iodized oil as markers for targeting. The technical success, technique effectiveness rate and complications of RFA were then assessed. On pre-ablative and immediate follow-up CT after RFA, we evaluated the size of enhancing index tumors and iodized oil retention, presence of abutting vessels, completeness of ablation of iodized oil retention, and the presence of ablative margins greater than 5 mm. Also, the time interval between transarterial chemoembolization and RFA was assessed. The cumulative local tumor progression rate was calculated using the Kaplan-Meier method, and the Cox proportional hazards model was adopted, to clarify the independent factors affecting local tumor progression. Results The technical success and technique effectiveness rate was 100% and 98.7%, respectively. Major complications were observed in 5.6%. The cumulative rates of local tumor progression at 1 and 2 years were 17.5% and 37.5%, respectively. In multivariate analyses, partial ablation of the targeted iodized oil retention was the sole independent predictor of a higher local tumor progression rate. Conclusion CT-guided RFA of HCC around iodized oil retention was effective and safe. Local tumor progression can be minimized by complete ablation of not only index tumors, but targeted iodized oil deposits as well. PMID:24043966

  18. Repeated Radiofrequency Ablation Combined With Ablated Lesion Elimination and Transarterial Chemoembolization Improves the Outcome of Solitary Huge Hepatocellular Carcinomas 10 cm or Larger.

    PubMed

    Ke, Shan; Gao, Jun; Kong, Jian; Ding, Xue-Mei; Niu, Hai-Gang; Xin, Zong-Hai; Ning, Chun-Min; Guo, Shi-Gang; Li, Xiao-Long; Zhang, Long; Dong, Yong-Hong; Sun, Wen-Bing

    2016-04-01

    This study investigated the effectiveness of a new strategy, repeated radiofrequency (RF) ablation combined with ablated lesion elimination following transarterial chemoembolization (TACE)/transarterial embolization (TAE), for solitary huge hepatocellular carcinoma (SHHCC) 10 cm or larger.From July 2008 to October 2015, 39 consecutive patients with SHHCC were screened. Of these, 12 were treated with TACE/TAE and repeated RF ablation (TACE/TAE + RF ablation group) and the remaining 27 patients were treated with the aforementioned new strategy (new strategy group). Local tumor progression (LTP)-free survival, intrahepatic distant recurrence (IDR)-free survival, and overall survival (OS) rates were obtained using the Kaplan-Meier method. Univariate and multivariate analyses were performed on several clinicopathological variables to identify factors affecting long-term outcome and intrahepatic recurrence. Correlation analysis was also performed.The 1-, 2-, and 3-year LTP-free survival rates and OS rates were significantly higher in the new strategy group than in the TACE/TAE + RF ablation group (82.9% vs 58.3%, 73.9% vs 29.2%, 18.5% vs 9.7%, P = 0.002; 92.0% vs 75.0%, 84.0% vs 33.3%, 32.7% vs 16.7%, P = 0.025). However, there was no significant difference between the 2 groups in the 1-, 2-, and 3-year IDR-free survival rates (P = 0.108). Using univariate analysis, alpha-fetoprotein (AFP > 200 ng/mL), ablative margin (AM > 1.0 cm), and well-differentiated cells were found to be significant factors for predicting LTP, IDR, and OS. Surgical elimination was found to be a significant factor only for predicting OS. In multivariate analyses, AFP (>200 ng/mL), AM (>1.0 cm), and well-differentiated cells were found to be significant independent factors linked to LTP, IDR, and OS. Correlation analysis indicated that AM > 1.0 cm was strongly associated with surgical elimination (P < 0.001, correlation coefficient = 0.877).For patients with SHHCC

  19. Repeated Radiofrequency Ablation Combined With Ablated Lesion Elimination and Transarterial Chemoembolization Improves the Outcome of Solitary Huge Hepatocellular Carcinomas 10 cm or Larger

    PubMed Central

    Ke, Shan; Gao, Jun; Kong, Jian; Ding, Xue-Mei; Niu, Hai-Gang; Xin, Zong-Hai; Ning, Chun-Min; Guo, Shi-Gang; Li, Xiao-Long; Zhang, Long; Dong, Yong-Hong; Sun, Wen-Bing

    2016-01-01

    Abstract This study investigated the effectiveness of a new strategy, repeated radiofrequency (RF) ablation combined with ablated lesion elimination following transarterial chemoembolization (TACE)/transarterial embolization (TAE), for solitary huge hepatocellular carcinoma (SHHCC) 10 cm or larger. From July 2008 to October 2015, 39 consecutive patients with SHHCC were screened. Of these, 12 were treated with TACE/TAE and repeated RF ablation (TACE/TAE + RF ablation group) and the remaining 27 patients were treated with the aforementioned new strategy (new strategy group). Local tumor progression (LTP)-free survival, intrahepatic distant recurrence (IDR)-free survival, and overall survival (OS) rates were obtained using the Kaplan–Meier method. Univariate and multivariate analyses were performed on several clinicopathological variables to identify factors affecting long-term outcome and intrahepatic recurrence. Correlation analysis was also performed. The 1-, 2-, and 3-year LTP-free survival rates and OS rates were significantly higher in the new strategy group than in the TACE/TAE + RF ablation group (82.9% vs 58.3%, 73.9% vs 29.2%, 18.5% vs 9.7%, P = 0.002; 92.0% vs 75.0%, 84.0% vs 33.3%, 32.7% vs 16.7%, P = 0.025). However, there was no significant difference between the 2 groups in the 1-, 2-, and 3-year IDR-free survival rates (P = 0.108). Using univariate analysis, alpha-fetoprotein (AFP > 200 ng/mL), ablative margin (AM > 1.0 cm), and well-differentiated cells were found to be significant factors for predicting LTP, IDR, and OS. Surgical elimination was found to be a significant factor only for predicting OS. In multivariate analyses, AFP (>200 ng/mL), AM (>1.0 cm), and well-differentiated cells were found to be significant independent factors linked to LTP, IDR, and OS. Correlation analysis indicated that AM > 1.0 cm was strongly associated with surgical elimination (P < 0.001, correlation coefficient = 0.877). For patients

  20. Economic and clinical benefits of endometrial radiofrequency ablation compared with other ablation techniques in women with menorrhagia: a retrospective analysis with German health claims data

    PubMed Central

    Bischoff-Everding, Christoph; Soeder, Ruediger; Neukirch, Benno

    2016-01-01

    Objective To evaluate the economic and clinical benefits of endometrial radiofrequency ablation (RFA) compared with other ablation techniques for the treatment of menorrhagia. Methods Using German health claims data, women meeting defined inclusion criteria for the intervention group (RFA) were selected. A comparable control group (other endometrial ablations) was established using propensity score matching. These two groups were compared during the quarter of treatment (QoT) and a follow-up of 2 years for the following outcomes: costs during QoT and during follow-up, repeated menorrhagia diagnoses during follow-up and necessary retreatments during follow-up. Results After performing propensity score matching, 50 cases could be allocated to the intervention group, while 38 were identified as control cases. Patients in the RFA group had 5% fewer repeat menorrhagia diagnoses (40% vs 45%; not significant) and 5% fewer treatments associated with recurrent menorrhagia (6% vs 11%; not significant) than cases in the control group. During the QoT, the RFA group incurred €578 additional costs (€2,068 vs €1,490; ns). However, during follow-up, the control group incurred €1,254 additional costs (€4,561 vs €5,815; ns), with medication, outpatient physician consultations, and hospitals costs being the main cost drivers. However, none of the results were statistically significant. Conclusion Although RFA was more cost-intensive in the QoT compared with other endometrial ablation techniques, an average total savings of €676 was generated during the follow-up period. While having evidence that RFA is clinically equivalent to other endometrial ablation procedures, we generated indications that RFA is non-inferior and favorable with regard to economic outcomes. PMID:26848277

  1. Radio-frequency ablation helps preserve nephrons in salvage of failed microwave ablation for a renal cancer in a solitary kidney.

    PubMed

    Castle, Scott M; Salas, Nelson; Leveillee, Raymond J

    2013-01-01

    Recurrent tumors after renal ablative therapy present a challenge for clinicians. New ablative modalities, including microwave ablation (MWA), have very limited experience in methods of retreating ablation failures. Additionally, in MWA, no long-term outcomes have been reported. In patients having local tumor recurrence, options for surveillance or surgical salvage must be assessed. We present a case to help assess radio-frequency ablation (RFA) for salvage of failed MWA. We report a 63-year-old male with a 4.33-cm renal mass in a solitary kidney undergoing laparoscopic MWA with simultaneous peripheral fiber-optic thermometry (Lumasense, Santa Clara, CA, USA) as primary treatment. Follow-up contrast-enhanced computed tomography (CT) scan was performed at 1 and 4.3 months post-op with failure occurring at 4.3 months as evidenced by persistent enhancement. Subsequently, a laparoscopic RFA (LRFA) with simultaneous peripheral fiber-optic thermometry was performed as salvage therapy. Clinical and radiological follow-up with a contrast-enhanced CT scan at 1 and 11 months post-RFA showed no evidence of disease or enhancement. Creatinine values pre-MWA, post-MWA, and post-RFA were 1.01, 1.14, and 1.17 mg/ml, respectively. This represents a 15% decrease in estimated glomerular filtration rate (eGFR) (79 to 67 ml/min) post-MWA and no change in eGFR post-RFA. Local kidney tumor recurrence often requires additional therapy and a careful decisionmaking process. It is desirable not only to preserve kidney function in patients with a solitary kidney or chronic renal insufficiency, but also to achieve cancer control. We show the feasibility of RFA for salvage treatment of local recurrence of a T1b tumor in a solitary kidney post-MWA. PMID:23662010

  2. The challenge of extraabdominal desmoid tumour management in patients with Gardner's syndrome: radiofrequency ablation, a promising option.

    PubMed

    Cobianchi, Lorenzo; Ravetta, Valentina; Viera, Francesca Torello; Filisetti, Claudia; Siri, Barbara; Segalini, Edoardo; Maestri, Marcello; Dominioni, Tommaso; Alessiani, Mario; Rossi, Sandro; Dionigi, Paolo

    2014-01-01

    Desmoid tumours are benign, myofibroblastic stromal neoplasms common in Gardner's syndrome, which is a subtype of familial adenomatous polyposis characterized by colonic polyps, osteomas, thyroid cancer, epidermoid cysts, fibromas and sebaceous cysts. The primary treatment is surgery, followed by adjuvant radiotherapy, but the local recurrence rate is high, and wide resection can result in debilitating loss of function. We report the case of a 39-year-old man with Gardner's syndrome who had already undergone a total prophylactic colectomy. He developed desmoid tumours localized in the mesenteric root, abdominal wall and dorsal region, which were treated from 2003 through 2013 with several surgical procedures and percutaneous radiofrequency ablation. In 2008 and 2013, RFA was applied under ultrasonographic guidance to two desmoid tumours localized in the dorsal thoracic wall. The outcomes were low-grade pain and one case of superficial skin necrosis, but so far there has been no recurrence of desmoid tumours in these locations. Surgical resection remains the first-line therapy for patients with desmoid tumours, but wide resection may lead to a poor quality of life. Radiofrequency ablation is less invasive and expensive and is a possible therapeutic option for desmoid tumours in patients with Gardner's syndrome. PMID:25429890

  3. Delayed bronchobiliary fistula following radiofrequency ablation in a patient with hepatocellular carcinoma: A case report and lesson regarding treatment

    PubMed Central

    ZENG, ZHAOLIN; CAI, MINGYUE; HUANG, WENSOU; HUANG, JINGJUN; CHEN, XIUZHEN; SHAN, HONG; ZHU, KANGSHUN

    2016-01-01

    Bronchobiliary fistula (BBF) is a rare complication of radiofrequency ablation (RFA) of hepatocellular carcinoma. The rupture of a biloma following RFA may result in the development of BBF, with their early detection and timely management important in the prevention of BBF. The current study presents a case of BBF, which developed at 17 months after radiofrequency ablation (RFA), due to biloma rupture in a patient with hepatocellular carcinoma. Despite the percutaneous drainage of the biloma following BBF, the persistent fever did not resolve due to biliary infection. Finally, an extensive surgical intervention was performed. The magnetic resonance imaging (MRI) scans that had been performed following RFA were reviewed, and it was found that the biloma and increased bile leakage had presented prior to biloma rupture. For that reason, it is advised that patients who present with biloma following RFA should receive regular follow-up MRI scans. Biloma enlargement could be a predictor for the development of BBF; therefore, timely drainage of an enlarging biloma may be able to prevent this complication. PMID:27123093

  4. Combination Therapy of Radiofrequency Ablation and Transarterial Chemoembolization for Unresectable Hepatocellular Carcinoma

    PubMed Central

    Tang, Chengwu; Shen, Jian; Feng, Wenming; Bao, Ying; Dong, Xiaogang; Dai, Yi; Zheng, Yinyuan; Zhang, Jianping

    2016-01-01

    Abstract The treatment efficacy of unresectable hepatocellular carcinoma (HCC) is still not promising. This study aimed to compare the efficacy and safety of radiofrequency ablation (RFA) combined with transarterial chemoembolization (TACE) for unresectable HCC with a single treatment. Between June 2009 and June 2012, 132 patients who were diagnosed with unresectable HCC and accepted nonsurgical treatments in our center were enrolled in this retrospective study. On the basis of treatment modality, they were allocated to 3 groups: 49 patients accepted RFA (RFA group); 43 patients accepted TACE (TACE group); and 40 patients accepted RFA following TACE (combination group). Clinical data including complications, treatment success rate, hospitalization costs, intrahepatic recurrence-free survival, overall survival, and factors influencing survival were retrospectively analyzed. Patient characteristics between these groups showed no significant difference. Treatment success was achieved in all patients of 3 groups. The combination group had a significantly higher total hospitalization cost to treatment than the TACE group (63,708.14 ± 9193.81 Chinese yuan vs 37,534.88 ± 6802.84 Chinese yuan; P = 0.0000). All complications were controllable and no permanent adverse sequelae or procedure-related deaths were observed. The 3-year intrahepatic recurrence-free survival probability was significantly better in the combination group than in the TACE group (42.50% vs 20.93%; hazard ratio [HR], 0.5105; 95% confidence interval [CI], 0.3022–0.8625; P = 0.0094) or the RFA group (42.50% vs 22.45%; HR, 0.5233; 95% CI, 0.3149–0.8697; P = 0.0111).The 3-year overall survival probability was significantly better in the combination group than in the TACE group (45.00% vs 26.53%; HR, 0.5069; 95% CI, 0.2936–0.8752; P = 0.0100) or the RFA group (45.00% vs 27.91%; HR, 0.4913; 95% CI, 0.2928–0.8246; P = 0.0054). Main tumor size, number of tumors, and

  5. Novel Radiofrequency Ablation Strategies for Terminating Atrial Fibrillation in the Left Atrium: A Simulation Study

    PubMed Central

    Bayer, Jason D.; Roney, Caroline H.; Pashaei, Ali; Jaïs, Pierre; Vigmond, Edward J.

    2016-01-01

    Pulmonary vein isolation (PVI) with radiofrequency ablation (RFA) is the cornerstone of atrial fibrillation (AF) therapy, but few strategies exist for when it fails. To guide RFA, phase singularity (PS) mapping locates reentrant electrical waves (rotors) that perpetuate AF. The goal of this study was to test existing and develop new RFA strategies for terminating rotors identified with PS mapping. It is unsafe to test experimental RFA strategies in patients, so they were evaluated in silico using a bilayer computer model of the human atria with persistent AF (pAF) electrical (ionic) and structural (fibrosis) remodeling. pAF was initiated by rapidly pacing the right (RSPV) and left (LSPV) superior pulmonary veins during sinus rhythm, and rotor dynamics quantified by PS analysis. Three RFA strategies were studied: (i) PVI, roof, and mitral lines; (ii) circles, perforated circles, lines, and crosses 0.5–1.5 cm in diameter/length administered near rotor locations/pathways identified by PS mapping; and (iii) 4–8 lines streamlining the sequence of electrical activation during sinus rhythm. As in pAF patients, 2 ± 1 rotors with cycle length 185 ± 4 ms and short PS duration 452 ± 401 ms perpetuated simulated pAF. Spatially, PS density had weak to moderate positive correlations with fibrosis density (RSPV: r = 0.38, p = 0.35, LSPV: r = 0.77, p = 0.02). RFA PVI, mitral, and roof lines failed to terminate pAF, but RFA perforated circles and lines 1.5 cm in diameter/length terminated meandering rotors from RSPV pacing when placed at locations with high PS density. Similarly, RFA circles, perforated circles, and crosses 1.5 cm in diameter/length terminated stationary rotors from LSPV pacing. The most effective strategy for terminating pAF was to streamline the sequence of activation during sinus rhythm with >4 RFA lines. These results demonstrate that co-localizing 1.5 cm RFA lesions with locations of high PS density is a promising strategy for terminating pAF rotors

  6. Novel Radiofrequency Ablation Strategies for Terminating Atrial Fibrillation in the Left Atrium: A Simulation Study.

    PubMed

    Bayer, Jason D; Roney, Caroline H; Pashaei, Ali; Jaïs, Pierre; Vigmond, Edward J

    2016-01-01

    Pulmonary vein isolation (PVI) with radiofrequency ablation (RFA) is the cornerstone of atrial fibrillation (AF) therapy, but few strategies exist for when it fails. To guide RFA, phase singularity (PS) mapping locates reentrant electrical waves (rotors) that perpetuate AF. The goal of this study was to test existing and develop new RFA strategies for terminating rotors identified with PS mapping. It is unsafe to test experimental RFA strategies in patients, so they were evaluated in silico using a bilayer computer model of the human atria with persistent AF (pAF) electrical (ionic) and structural (fibrosis) remodeling. pAF was initiated by rapidly pacing the right (RSPV) and left (LSPV) superior pulmonary veins during sinus rhythm, and rotor dynamics quantified by PS analysis. Three RFA strategies were studied: (i) PVI, roof, and mitral lines; (ii) circles, perforated circles, lines, and crosses 0.5-1.5 cm in diameter/length administered near rotor locations/pathways identified by PS mapping; and (iii) 4-8 lines streamlining the sequence of electrical activation during sinus rhythm. As in pAF patients, 2 ± 1 rotors with cycle length 185 ± 4 ms and short PS duration 452 ± 401 ms perpetuated simulated pAF. Spatially, PS density had weak to moderate positive correlations with fibrosis density (RSPV: r = 0.38, p = 0.35, LSPV: r = 0.77, p = 0.02). RFA PVI, mitral, and roof lines failed to terminate pAF, but RFA perforated circles and lines 1.5 cm in diameter/length terminated meandering rotors from RSPV pacing when placed at locations with high PS density. Similarly, RFA circles, perforated circles, and crosses 1.5 cm in diameter/length terminated stationary rotors from LSPV pacing. The most effective strategy for terminating pAF was to streamline the sequence of activation during sinus rhythm with >4 RFA lines. These results demonstrate that co-localizing 1.5 cm RFA lesions with locations of high PS density is a promising strategy for terminating pAF rotors. For

  7. Lymphocyte-to-monocyte ratio predicts survival after radiofrequency ablation for colorectal liver metastases

    PubMed Central

    Facciorusso, Antonio; Del Prete, Valentina; Crucinio, Nicola; Serviddio, Gaetano; Vendemiale, Gianluigi; Muscatiello, Nicola

    2016-01-01

    AIM: To test the correlation between lymphocyte-to-monocyte ratio (LMR) and survival after radiofrequency ablation (RFA) for colorectal liver metastasis (CLMs). METHODS: From July 2003 to Feb 2012, 127 consecutive patients with 193 histologically-proven unresectable CLMs were treated with percutaneous RFA at the University of Foggia. All patients had undergone primary colorectal tumor resection before RFA and received systemic chemotherapy. LMR was calculated by dividing lymphocyte count by monocyte count assessed at baseline. Treatment-related toxicity was defined as any adverse events occurred within 4 wk after the procedure. Overall survival (OS) and time to recurrence (TTR) were estimated from the date of RFA by Kaplan-Meier with plots and median (95%CI). The inferential analysis for time to event data was conducted using the Cox univariate and multivariate regression model to estimate hazard ratios (HR) and 95%CI. Statistically significant variables from the univariate Cox analysis were considered for the multivariate models. RESULTS: Median age was 66 years (range 38-88) and patients were prevalently male (69.2%). Median LMR was 4.38% (0.79-88) whereas median number of nodules was 2 (1-3) with a median maximum diameter of 27 mm (10-45). Median OS was 38 mo (34-53) and survival rate (SR) was 89.4%, 40.4% and 33.3% at 1, 4 and 5 years respectively in the whole cohort. Running log-rank test analysis found 3.96% as the most significant prognostic cut-off point for LMR and stratifying the study population by this LMR value median OS resulted 55 mo (37-69) in patients with LMR > 3.96% and 34 (26-39) mo in patients with LMR ≤ 3.96% (HR = 0.53, 0.34-0.85, P = 0.007). Nodule size and LMR were the only significant predictors for OS in multivariate analysis. Median TTR was 29 mo (22-35) with a recurrence-free survival (RFS) rate of 72.6%, 32.1% and 21.8% at 1, 4 and 5 years, respectively in the whole study group. Nodule size and LMR were confirmed as significant

  8. Combination Therapy of Radiofrequency Ablation and Transarterial Chemoembolization for Unresectable Hepatocellular Carcinoma: A Retrospective Study.

    PubMed

    Tang, Chengwu; Shen, Jian; Feng, Wenming; Bao, Ying; Dong, Xiaogang; Dai, Yi; Zheng, Yinyuan; Zhang, Jianping

    2016-05-01

    The treatment efficacy of unresectable hepatocellular carcinoma (HCC) is still not promising. This study aimed to compare the efficacy and safety of radiofrequency ablation (RFA) combined with transarterial chemoembolization (TACE) for unresectable HCC with a single treatment.Between June 2009 and June 2012, 132 patients who were diagnosed with unresectable HCC and accepted nonsurgical treatments in our center were enrolled in this retrospective study. On the basis of treatment modality, they were allocated to 3 groups: 49 patients accepted RFA (RFA group); 43 patients accepted TACE (TACE group); and 40 patients accepted RFA following TACE (combination group). Clinical data including complications, treatment success rate, hospitalization costs, intrahepatic recurrence-free survival, overall survival, and factors influencing survival were retrospectively analyzed.Patient characteristics between these groups showed no significant difference. Treatment success was achieved in all patients of 3 groups. The combination group had a significantly higher total hospitalization cost to treatment than the TACE group (63,708.14 ± 9193.81 Chinese yuan vs 37,534.88 ± 6802.84 Chinese yuan; P = 0.0000). All complications were controllable and no permanent adverse sequelae or procedure-related deaths were observed. The 3-year intrahepatic recurrence-free survival probability was significantly better in the combination group than in the TACE group (42.50% vs 20.93%; hazard ratio [HR], 0.5105; 95% confidence interval [CI], 0.3022-0.8625; P = 0.0094) or the RFA group (42.50% vs 22.45%; HR, 0.5233; 95% CI, 0.3149-0.8697; P = 0.0111).The 3-year overall survival probability was significantly better in the combination group than in the TACE group (45.00% vs 26.53%; HR, 0.5069; 95% CI, 0.2936-0.8752; P = 0.0100) or the RFA group (45.00% vs 27.91%; HR, 0.4913; 95% CI, 0.2928-0.8246; P = 0.0054). Main tumor size, number of tumors, and treatment modality were

  9. Percutaneous Radiofrequency Ablation of Lung Tumors in Contact with the Aorta: Dangerous and Difficult but Efficient: A Report of Two Cases

    SciTech Connect

    Thanos, Loukas; Mylona, Sofia; Giannoulakos, Nikolaos; Ptohis, Nikolaos; Galani, Panagiota; Pomoni, Maria

    2008-11-15

    Percutaneous imaging-guided tumor ablation is a widely accepted method for the treatment of primary and secondary lung tumors. Although it is generally feasible and effective for local tumor control, some conditions may affect its feasibility and effectiveness. Herein the authors report their experience with two patients with lung malignancies contiguous to the aorta who were successfully treated with radiofrequency ablation, even though it initially appeared highly risky due to the possible fatal complications.

  10. Hepatic Radiofrequency Ablation Using Multiple Probes: Ex Vivo and In Vivo Comparative Studies of Monopolar versus Multipolar Modes

    PubMed Central

    Lee, Jeong Min; Lee, Jae Young; Kim, Se Hyung; Choi, Jin Young; Lee, Min Woo; Choi, Seung Hong; Eo, Hong; Choi, Byung Ihn

    2006-01-01

    Objective We wanted to compare the efficiency of multipolar radiofrequency ablation (RFA) using three perfused-cooled electrodes with multiple overlapping and simultaneous monopolar techniques for creating an ablation zone in ex vivo bovine livers and in in vivo porcine livers. Materials and Methods In the ex vivo experiments, we used a 200 W generator (Valleylab, CC-3 model) and three perfused-cooled electrodes or internally cooled electrodes to create 30 coagulation zones by performing consecutive monopolar RFA (group A, n = 10), simultaneous monopolar RFA (group B, n = 10) or multipolar RFA (group C, n = 10) in explanted bovine livers. In the consecutive mode, three ablation spheres were created by sequentially applying 150 watts radiofrequency (RF) energy to the internally cooled electrodes for 12 minutes each for a total of 36 minutes. In the simultaneous monopolar and multipolar modes, RF energy was concurrently applied to the three perfused-cooled electrodes for 20 minutes at 150 watt with instillation of 6% hypertonic saline at 2 mL/min. During RFA, we measured the temperatures of the treated area at its center. The changes in impedance, the current and liver temperature during RFA, as well as the dimensions of the thermal ablation zones, were compared among the three groups. In the in vivo experiments, three coagulations were created by performing multipolar RFA in a pig via laparotomy with using same parameter as the ex vivo study. Results In the ex vivo experiments, the impedance was gradually decreased during the RFA in groups B and C, but in group A, the impedance was increased during RFA and this induced activation by the pulsed RF technique. In groups A, B and C, the mean final-temperature values were 80±10℃, 69±18℃and 79±12℃, respectively (p < 0.05). The multipolar mode created a larger volume of ablation than did the other modes: 37.6±4.0 cm3 (group A); 44.9±12.7 cm3 (group B); and 78.9±6.9 cm3 (group C) (p < 0.05). In the in vivo

  11. Safety and efficacy of multipolar pulmonary vein ablation catheter vs. irrigated radiofrequency ablation for paroxysmal atrial fibrillation: a randomized multicentre trial

    PubMed Central

    McCready, J.; Chow, A. W.; Lowe, M. D.; Segal, O. R.; Ahsan, S.; de Bono, J.; Dhaliwal, M.; Mfuko, C.; Ng, A.; Rowland, E. R.; Bradley, R. J. W.; Paisey, J.; Roberts, P.; Morgan, J. M.; Sandilands, A.; Yue, A.; Lambiase, P. D.

    2014-01-01

    Aims The current challenge in atrial fibrillation (AF) treatment is to develop effective, efficient, and safe ablation strategies. This randomized controlled trial assesses the medium-term efficacy of duty-cycled radiofrequency ablation via the circular pulmonary vein ablation catheter (PVAC) vs. conventional electro-anatomically guided wide-area circumferential ablation (WACA). Methods and results One hundred and eighty-eight patients (mean age 62 ± 12 years, 116 M : 72 F) with paroxysmal AF were prospectively randomized to PVAC or WACA strategies and sequentially followed for 12 months. The primary endpoint was freedom from symptomatic or documented >30 s AF off medications for 7 days at 12 months post-procedure. One hundred and eighty-three patients completed 12 m follow-up. Ninety-four patients underwent PVAC PV isolation with 372 of 376 pulmonary veins (PVs) successfully isolated and all PVs isolated in 92 WACA patients. Three WACA and no PVAC patients developed tamponade. Fifty-six percent of WACA and 60% of PVAC patients were free of AF at 12 months post-procedure (P = ns) with a significant attrition rate from 77 to 78%, respectively, at 6 months. The mean procedure (140 ± 43 vs. 167 ± 42 min, P<0.0001), fluoroscopy (35 ± 16 vs. 42 ± 20 min, P<0.05) times were significantly shorter for PVAC than for WACA. Two patients developed strokes within 72 h of the procedure in the PVAC group, one possibly related directly to PVAC ablation in a high-risk patient and none in the WACA group (P = ns). Two of the 47 patients in the PVAC group who underwent repeat ablation had sub-clinical mild PV stenoses of 25–50% and 1 WACA patient developed delayed severe PV stenosis requiring venoplasty. Conclusion The pulmonary vein ablation catheter is equivalent in efficacy to WACA with reduced procedural and fluoroscopy times. However, there is a risk of thrombo-embolic and pulmonary stenosis complications which needs to be addressed and prospectively monitored. Clinical

  12. Hepatic radiofrequency ablation: in vivo and ex vivo comparisons of 15-gauge (G) and 17-G internally cooled electrodes

    PubMed Central

    Song, K D; Park, H J; Cha, D I; Kang, T W; Lee, J; Moon, J Y; Rhim, H

    2015-01-01

    Objective: To compare the performance of the 15-G internally cooled electrode with that of the conventional 17-G internally cooled electrode. Methods: A total of 40 (20 for each electrode) and 20 ablation zones (10 for each electrode) were made in extracted bovine livers and in in vivo porcine livers, respectively. Technical parameters, three dimensions [long-axis diameter (Dl), vertical-axis diameter (Dv) and short-axis diameter (Ds)], volume and the circularity (Ds/Dl) of the ablation zone were compared. Results: The total delivered energy was higher in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (8.78 ± 1.06 vs 7.70 ± 0.98 kcal, p = 0.033; 11.20 ± 1.13 vs 8.49 ± 0.35 kcal, p = 0.001, respectively). The three dimensions of the ablation zone had a tendency to be larger in the 15-G group than in the 17-G group in both studies. The ablation volume was larger in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (29.61 ± 7.10 vs 23.86 ± 3.82 cm3, p = 0.015; 10.26 ± 2.28 vs 7.79 ± 1.68 cm3, p = 0.028, respectively). The circularity of ablation zone was not significantly different in both the studies. Conclusion: The size of ablation zone was larger in the 15-G internally cooled electrode than in the 17-G electrode in both ex vivo and in vivo studies. Advances in knowledge: Radiofrequency ablation of hepatic tumours using 15-G electrode is useful to create larger ablation zones. PMID:25882688

  13. Prospective study of left ventricular function after radiofrequency ablation of atrioventricular junction in patients with atrial fibrillation.

    PubMed Central

    Edner, M.; Caidahl, K.; Bergfeldt, L.; Darpö, B.; Edvardsson, N.; Rosenqvist, M.

    1995-01-01

    BACKGROUND--In patients with drug resistant incessant supraventricular tachycardia, radiofrequency induced ablation of the atrioventricular junction and pacemaker implantation have hitherto been considered a treatment of last resort. OBJECTIVE--To assess the short and long term effects of ablation of the atrioventricular junction on systolic and diastolic left ventricular function in patients with atrial fibrillation with and without impaired left ventricular function. PATIENTS--29 patients (19 men; mean age 65 (SD 7) years (range 50-76)) undergoing ablation of the atrioventricular junction for drug refractory atrial fibrillation were examined a mean of 2, 65, and 216 days after ablation of the bundle of His. MAIN OUTCOME MEASURES--Left ventricular ejection fraction and early filling deceleration times (Edec) were assessed by Doppler echocardiography after 1 to 2 hours of ventricular pacing at a rate of 80 beats/minute. RESULTS--In 14 patients with a left ventricular ejection fraction < 50% left ventricular ejection fraction increased significantly from 32% (11%) to 39% (11%) (65 days) and 45% (11%) (216 days) (P < 0.001); Edec increased from 142 (46) ms to 169 (57) ms (65 days) and 167 (56) ms (216 days) (P < 0.05). In 15 patients with an ejection fraction > or = 50% at the initial examination no significant change in systolic function was observed. CONCLUSIONS--In patients with left ventricular dysfunction long term improvement of systolic and diastolic left ventricular function was seen after ablation of the atrioventricular junction for rate control of atrial fibrillation. This procedure had no adverse effects on normal left ventricular function. PMID:7547020

  14. Terminology and Reporting Criteria for Radiofrequency Ablation of Tumors in the Scientific Literature: Systematic Review of Compliance with Reporting Standards

    PubMed Central

    Kang, Tae Wook; Lee, Min Woo; Kim, Young-sun; Choi, Dongil; Lim, Hyo Keun

    2014-01-01

    Objective To perform a systematic review of compliance with standardized terminology and reporting criteria for radiofrequency (RF) tumor ablation, proposed by the International Working Group on Image-Guided Tumor Ablation in 2003, in the published reports. Materials and Methods Literature search in the PubMed database was performed using index keywords, PubMed limit system, and eligibility criteria. The entire content of each article was reviewed to assess the terminology used for procedure terms, imaging findings, therapeutic efficacy, follow-up, and complications. Accuracy of the terminology and the use of alternative terms instead of standard terminology were analyzed. In addition, disparities in accuracy of terminology in articles according to the medical specialty and the type of radiology journal were evaluated. Results Among the articles (n = 308) included in this study, the accuracy of the terms 'procedure or session', 'treatment', 'index tumor', 'ablation zone', 'technical success', 'primary technique effectiveness rate', 'secondary technique effectiveness rate', 'local tumor progression', 'major complication', and 'minor complication' was 97% (298/307), 97% (291/300), 8% (25/307), 65% (103/159), 55% (52/94), 33% (42/129), 94% (17/18), 45% (88/195), 99% (79/80), and 100% (77/77), respectively. The overall accuracy of each term showed a tendency to improve over the years. The most commonly used alternative terms for 'technical success' and 'local tumor progression' were 'complete ablation' and 'local (tumor) recurrence', respectively. The accuracy of terminology in articles published in radiology journals was significantly greater than that of terminology in articles published in non-radiology journals, especially in Radiology and The Journal of Vascular and Interventional Radiology. Conclusion The proposal for standardization of terminology and reporting criteria for RF tumor ablation has been gaining support according to the recently published scientific

  15. Mathematical spatio-temporal model of drug delivery from low temperature sensitive liposomes during radiofrequency tumour ablation

    PubMed Central

    GASSELHUBER, ASTRID; DREHER, MATTHEW R.; NEGUSSIE, AYELE; WOOD, BRADFORD J.; RATTAY, FRANK; HAEMMERICH, DIETER

    2010-01-01

    Purpose Studies have demonstrated a synergistic effect between hyperthermia and chemotherapy, and clinical trials in image-guided drug delivery combine high-temperature thermal therapy (ablation) with chemotherapy agents released in the heating zone via low temperature sensitive liposomes (LTSL). The complex interplay between heat-based cancer treatments such as thermal ablation and chemotherapy may require computational models to identify the relationship between heat exposure and pharmacokinetics in order to optimise drug delivery. Materials and methods Spatio-temporal data on tissue temperature and perfusion from heat-transfer models of radiofrequency ablation were used as input data. A spatio-temporal multi-compartmental pharmacokinetic model was built to describe the release of doxorubicin (DOX) from LTSL into the tumour plasma space, and subsequent transport into the extracellular space, and the cells. Systemic plasma and tissue compartments were also included. We compared standard chemotherapy (free-DOX) to LTSL-DOX administered as bolus at a dose of 0.7 mg/kg body weight. Results Modelling LTSL-DOX treatment resulted in tumour tissue drug concentration of ~9.3 μg/g with highest values within 1 cm outside the ablation zone boundary. Free-DOX treatment produced comparably uniform tissue drug concentrations of ~3.0 μg/g. Administration of free-DOX resulted in a considerably higher peak level of drug concentration in the systemic plasma compartment (16.1 μg/g) compared to LTSL-DOX (4.4 μg/g). These results correlate well with a prior in vivo study. Conclusions Combination of LTSL-DOX with thermal ablation allows localised drug delivery with higher tumour tissue concentrations than conventional chemotherapy. Our model may facilitate drug delivery optimisation via investigation of the interplays among liposome properties, tumour perfusion, and heating regimen. PMID:20377363

  16. Treatment Planning and Image Guidance for Radiofrequency Ablations of Large Tumors

    PubMed Central

    Ren, Hongliang; Campos-Nanez, Enrique; Yaniv, Ziv; Banovac, Filip; Abeledo, Hernan; Hata, Nobuhiko; Cleary, Kevin

    2014-01-01

    This article addresses the two key challenges in computer-assisted percutaneous tumor ablation: planning multiple overlapping ablations for large tumors while avoiding critical structures, and executing the prescribed plan. Towards semi-automatic treatment planning for image-guided surgical interventions, we develop a systematic approach to the needle-based ablation placement task, ranging from pre-operative planning algorithms to an intra-operative execution platform. The planning system incorporates clinical constraints on ablations and trajectories using a multiple objective optimization formulation, which consists of optimal path selection and ablation coverage optimization based on integer programming. The system implementation is presented and validated in phantom studies and on an animal model. The presented system can potentially be further extended for other ablation techniques such as cryotherapy. PMID:24235279

  17. Optimization of tissue physical parameters for accurate temperature estimation from finite-element simulation of radiofrequency ablation.

    PubMed

    Subramanian, Swetha; Mast, T Douglas

    2015-10-01

    Computational finite element models are commonly used for the simulation of radiofrequency ablation (RFA) treatments. However, the accuracy of these simulations is limited by the lack of precise knowledge of tissue parameters. In this technical note, an inverse solver based on the unscented Kalman filter (UKF) is proposed to optimize values for specific heat, thermal conductivity, and electrical conductivity resulting in accurately simulated temperature elevations. A total of 15 RFA treatments were performed on ex vivo bovine liver tissue. For each RFA treatment, 15 finite-element simulations were performed using a set of deterministically chosen tissue parameters to estimate the mean and variance of the resulting tissue ablation. The UKF was implemented as an inverse solver to recover the specific heat, thermal conductivity, and electrical conductivity corresponding to the measured area of the ablated tissue region, as determined from gross tissue histology. These tissue parameters were then employed in the finite element model to simulate the position- and time-dependent tissue temperature. Results show good agreement between simulated and measured temperature. PMID:26352462

  18. A comparative study of the efficacy and safety of radiofrequency ablation and botulinum toxin A in treating masseteric hypertrophy

    PubMed Central

    HUANG, JIN-LONG; CHEN, GANG; CHEN, XIAO-DONG; ZHOU, BING-RONG; LUO, DAN

    2014-01-01

    The aim of the present study was to evaluate the effects of two treatments for masseteric hypertrophy. In total, 24 patients with masseteric hypertrophy were enrolled in this study. Patients were randomly divided into two groups: 12 individuals were treated with radiofrequency (RF) ablation and 12 patients received an injection of botulinum toxin A. The thickness of the masseter muscle under tension was measured using ultrasound and clinical photographs were captured prior to treatment and at 6 and 12 months following treatment. Complications were observed during 12-month follow-up. In the group injected with botulinum toxin A, masseteric muscle thickness decreased to the lowest point 6 months after the injections but increased until 12 months after injection. However, in the group treated with RF ablation, muscle thickness decreased steadily over the 12 months following surgery. Therefore, the results of the present study indicated that the effect of RF ablation on the thickness of the masseter muscle may be much larger than that obtained following injection with botulinum toxin A. PMID:24940412

  19. Optimization of tissue physical parameters for accurate temperature estimation from finite-element simulation of radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Subramanian, Swetha; Mast, T. Douglas

    2015-09-01

    Computational finite element models are commonly used for the simulation of radiofrequency ablation (RFA) treatments. However, the accuracy of these simulations is limited by the lack of precise knowledge of tissue parameters. In this technical note, an inverse solver based on the unscented Kalman filter (UKF) is proposed to optimize values for specific heat, thermal conductivity, and electrical conductivity resulting in accurately simulated temperature elevations. A total of 15 RFA treatments were performed on ex vivo bovine liver tissue. For each RFA treatment, 15 finite-element simulations were performed using a set of deterministically chosen tissue parameters to estimate the mean and variance of the resulting tissue ablation. The UKF was implemented as an inverse solver to recover the specific heat, thermal conductivity, and electrical conductivity corresponding to the measured area of the ablated tissue region, as determined from gross tissue histology. These tissue parameters were then employed in the finite element model to simulate the position- and time-dependent tissue temperature. Results show good agreement between simulated and measured temperature.

  20. Intraoperative radiofrequency ablation combined with 125iodine seed implantation for unresectable pancreatic cancer

    PubMed Central

    Zou, Yi-Ping; Li, Wei-Min; Zheng, Fang; Li, Fu-Cheng; Huang, Hui; Du, Ji-Dong; Liu, Hao-Run

    2010-01-01

    AIM: To evaluate the feasibility, efficacy and safety of intraoperative radiofrequency ablation (RFA) combined with 125iodine seed implantation for unresectable pancreatic cancer. METHODS: Thirty-two patients (21 males and 11 females) at the age of 68 years (range 48-90 years) with unresectable locally advanced pancreatic cancer admitted to our hospital from January 2006 to May 2008 were enrolled in this study. The tumor, 4-12 cm in diameter, located in pancreatic head of 23 patients and in pancreatic body and tail of 9 patients, was found to be unresectable during operation. Diagnosis of pancreatic cancer was made through intraoperative biopsy. Patients were treated with FRA combined with 125iodine seed implantation. In brief, a RFA needle was placed, which was confirmed by intraoperative ultrasound to decrease the potential injury of surrounding vital structures, a 125iodine seed was implanted near the blood vessels and around the tumor border followed by bypass palliative procedure (cholangio-jejunostomy and/or gastrojejunostomy) in 29 patients. RESULTS: The serum CA 19-9 level was decreased from 512 ± 86 U/mL before operation to 176 ± 64 U/mL, 108 ± 42 U/mL and 114 ± 48 U/mL, respectively, 1, 3 and 6 mo after operation (P < 0.05). The pain score on day 7 after operation, 1 and 3 mo after combined therapy was decreased from 5.86 ± 1.92 before operation to 2.65 ± 1.04, 1.65 ± 0.88 and 2.03 ± 1.16, respectively, after operation (P < 0.05). The rate of complete response (CR), partial response (PR), stable disease (SD), progressive disease (PD) in 32 patients was 21.8% (7/32), 56.3% (18/32), 15.6% (5/32) and 6.3% (2/32), respectively, 6 mo after operation, with a median overall survival time of 17. 5 mo. The median survival time of patients at stage III was longer than that of those at stage IV (19 mo vs 10 mo, P = 0.0026). The median survival time of patients who received and did not receive chemotherapy after operation was 20 mo and 16 mo, respectively (P

  1. Ablative therapies: Advantages and disadvantages of radiofrequency, cryotherapy, microwave and electroporation methods, or how to choose the right method for an individual patient?

    PubMed

    Seror, O

    2015-06-01

    Several ablation techniques are currently available. Except for electroporation, all of these methods cause fatal damage at a cellular level and irreversible architectural deconstruction at a tissue level by thermal effects. Ablation of a tumor using one of these techniques, whether thermal or otherwise, requires applicators to be positioned from which the energy is delivered in situ. Some techniques, however, require several applicators to be inserted (multibipolar radiofrequency, cryotherapy and electroporation) whereas a single applicator is often sufficient with other technologies (monopolar radiofrequency and microwave). These methods are conceptually very similar but are distinguished from each other in practice through the technologies they use. It is essential to understand these differences as they influence the advantages and limitations of each of the techniques. There is no such thing as the perfect multifunctional ablation device and choice is dictated on an individual patient basis depending on the aim of treatment, which itself depends on each patient's clinical situation. PMID:25981214

  2. Non-invasive radiofrequency ablation of malignancies mediated by quantum dots, gold nanoparticles and carbon nanotubes

    PubMed Central

    Glazer, Evan S; Curley, Steven A

    2013-01-01

    Various types of nanoparticles efficiently heat in radiofrequency fields, which can potentially be used to produce cancer cell cytotoxicity within minutes. Multifunctional and targeted nanoparticles have demonstrated effective cancer control in vivo without significant toxicity associated with radiofrequency field exposure. Importantly, animals treated systemically with targeted nanoparticles smaller than 50 nm demonstrate tumor necrosis after radiofrequency field exposure without acute or chronic toxicity to normal tissues. Likewise, the future holds great promise for multifunctional imaging as well as multimodality therapy with chemotherapeutic molecules and ionizing radiation sensitizing agents attached to nanoparticle constructs. However, the appropriate balance of safety and efficacy for diagnosis, therapy, and therapeutic monitoring with these nanoparticles remains to be fully elucidated. PMID:22826886

  3. Comparison between the treatment area of electrode used for radiofrequency ablation of liver cancer focusing on 15G cooled-tip and CWT electrode

    PubMed Central

    Kim, Hyun-Jin; Lee, Hae-Kag; Cho, Jae-Hwan

    2016-01-01

    Objectives: To analyze the comparison between the treatment area of 15Gage internally cooled electrodes and 17 Gage Cool Wet-tip(CWT) electrodes. They are manufactured to broaden treatment area of the tumor in the radiofrequency ablation of hepatocellular carcinoma(HCC). Methods: The study was designed for 62 patients with a mean age of 61, ranging from 44 to 87 years. The sample comprised of patients who used 15 G internally cooled electrodes and 17 G CWT electrodes respectively. Computed tomography (CT) images obtained after the procedure were observed, however, for the ablation lesion, the volume was determined by measuring complete necrotic tissue that did not contrast enhancement in the image. Results: The treatment area of the tumor after radiofrequency ablation was 17.26±6.02 in the CWT, which was bigger than 15G. The treatment area ratio of the treatment before or after was significant at 581.85±339.56 in the CWT. After radiofrequency ablation, the treatment area got bigger, as 15G electrodes went toward CWT electrodes. Treatment area per electrode was 1.34 times higher in CWT than in 15G while the treatment area ratio of the treatment before or after was 1.001 times higher in the CWT than 15G. Conclusions: Ablation is more common for the safety margin in stable tumor and CWT type electrodes that can make larger ablation to reduce the number of times ablation is required for residual tumor and it decreases recurrence, ablation time and reoperation. Therefore it is considered t useful to reduce patients’ pain. PMID:27375688

  4. Radiofrequency Volumetric Thermal Ablation of Fibroids and Laparoscopic Myomectomy: Long-Term Follow-up From a Randomized Trial

    PubMed Central

    Hahn, M.; Brucker, S.; Kraemer, D.; Wallwiener, M.; Taran, F.-A.; Wallwiener, C. W.; Krämer, B.

    2015-01-01

    Aims: Laparoscopic myomectomy (LM) has been the gold standard treatment for uterine fibroids in women desiring uterine conservation. To evaluate a new fibroid treatment modality – radiofrequency volumetric thermal ablation (RFVTA) – we compare 12-month results in women who had symptomatic uterine fibroids and who were randomized to laparoscopic ultrasound-guided RFVTA or LM. Materials and Methods: Our study is a 1 : 1 parallel, randomized, prospective, single-center, longitudinal, comparative analysis of RFVTA to LM for fibroid treatment in women ≥ 18 years of age who desired uterine conservation. Fifty women were randomized intraoperatively to RFVTA (n = 25) or to LM (n = 25) after laparoscopic ultrasound mapping of the uterus. Results: Post surgery, ablation and myomectomy subjects took pain medications for 4 days (range: 1–46) and 7 days (range: 1–83 days) respectively (p = 0.60). Ablation and myomectomy subjects missed 10.0 workdays (range: 2–86 days) and 17.0 workdays (range: 7–30 days) (p = 0.28), resumed normal activities in 20.5 days (range: 5–103 days) versus 28.0 days (range: 10–42 days) (p = 0.86) respectively. Mean symptom severity scores decreased (improved) by − 7.8 for the ablation subjects and by − 17.9 for the myomectomy subjects (p = 0.16). Health-related quality of life improved (increased) by 7.5 and 13.1, respectively, for the two groups (p = 0.46). Two myomectomy subjects had pregnancies that ended in a Cesarean delivery and a vaginal delivery of healthy infants. Two pregnancies in the RFVTA group ended in full-term vaginal deliveries of healthy infants. Conclusions: Early postoperative recovery and twelve-month results attest to similar clinical benefits from RFVTA and LM. PMID:26097247

  5. Does Thermosensitive Liposomal Vinorelbine Improve End-Point Survival after Percutaneous Radiofrequency Ablation of Liver Tumors in a Mouse Model?

    PubMed

    Wang, Song; Mei, Xing-Guo; Goldberg, S Nahum; Ahmed, Muneeb; Lee, Jung-Chieh; Gong, Wei; Han, Hai-Bo; Yan, Kun; Yang, Wei

    2016-06-01

    Purpose To investigate the role of thermosensitive liposome-encapsulated vinorelbine (Thermo-Vin) in combined radiofrequency (RF) ablation of liver tumors. Materials and Methods Approval from the institutional animal care and use committee was obtained before this study. First, the anticancer efficacy of Thermo-Vin was assessed in vitro (H22 cells) for 72 hours at 37°C or 42°C. Next, 203 H22 liver adenocarcinomas were implanted in 191 mice for in vivo study. Tumors were randomized into seven groups: (a) no treatment, (b) treatment with RF ablation alone, (c) treatment with RF ablation followed by free vinorelbine (Free-Vin) at 30 minutes, (d) treatment with RF ablation followed by empty liposomes (Empty-Lip+RF), (e) treatment with RF ablation followed by Thermo-Vin (5 mg/kg), (f) treatment with RF ablation followed by Thermo-Vin (10 mg/kg), and (g) treatment with RF ablation followed by Thermo-Vin (20 mg/kg). Tumor destruction areas and pathologic changes were compared for different groups at 24 and 72 hours after treatment. Kaplan-Meier analysis was used to compare end-point survival (tumor < 30 mm in diameter). Additionally, the effect of initial tumor size on long-term outcome was analyzed. Results In vitro, both Free-Vin and Thermo-Vin dramatically inhibited H22 cell viability at 24 hours. Likewise, in vivo, 10 mg/kg Thermo-Vin+RF ablation increased tumor destruction compared with RF ablation (P = .001). Intratumoral vinorelbine accumulation with Thermo-Vin+RF increased 15-fold compared with Free-Vin alone. Thermo-Vin substantially increased apoptosis at the coagulation margin and suppressed cellular proliferation in the residual tumor (P < .001). The Thermo-Vin+RF study arm also had better survival than the arm treated with RF ablation alone (mean, 37.6 days ± 20.1 vs 23.4 days ± 5.0; P = .001), the arm treated with Free-Vin+RF (23.3 days ± 1.2, P = .002), or the arm treated with Empty-Lip+RF (20.8 days ± 0.4, P < .001) in animals with medium-sized (10

  6. Near-infrared spectroscopy integrated catheter for characterization of myocardial tissues: preliminary demonstrations to radiofrequency ablation therapy for atrial fibrillation

    PubMed Central

    Singh-Moon, Rajinder P.; Marboe, Charles C.; Hendon, Christine P.

    2015-01-01

    Effects of radiofrequency ablation (RFA) treatment of atrial fibrillation can be limited by the ability to characterize the tissue in contact. Parameters obtained by conventional catheters, such as impedance and temperature can be insufficient in providing physiological information pertaining to effective treatment. In this report, we present a near-infrared spectroscopy (NIRS)-integrated catheter capable of extracting tissue optical properties. Validation experiments were first performed in tissue phantoms with known optical properties. We then apply the technique for characterization of myocardial tissues in swine and human hearts, ex vivo. Additionally, we demonstrate the recovery of critical parameters relevant to RFA therapy including contact verification, and lesion transmurality. These findings support the application of NIRS for improved guidance in RFA therapeutic interventions. PMID:26203376

  7. Near-infrared spectroscopy integrated catheter for characterization of myocardial tissues: preliminary demonstrations to radiofrequency ablation therapy for atrial fibrillation.

    PubMed

    Singh-Moon, Rajinder P; Marboe, Charles C; Hendon, Christine P

    2015-07-01

    Effects of radiofrequency ablation (RFA) treatment of atrial fibrillation can be limited by the ability to characterize the tissue in contact. Parameters obtained by conventional catheters, such as impedance and temperature can be insufficient in providing physiological information pertaining to effective treatment. In this report, we present a near-infrared spectroscopy (NIRS)-integrated catheter capable of extracting tissue optical properties. Validation experiments were first performed in tissue phantoms with known optical properties. We then apply the technique for characterization of myocardial tissues in swine and human hearts, ex vivo. Additionally, we demonstrate the recovery of critical parameters relevant to RFA therapy including contact verification, and lesion transmurality. These findings support the application of NIRS for improved guidance in RFA therapeutic interventions. PMID:26203376

  8. Percutaneous Tumor Ablation Tools: Microwave, Radiofrequency, or Cryoablation—What Should You Use and Why?

    PubMed Central

    Lubner, Meghan G.; Ziemlewicz, Timothy J.; Lee, Fred T.; Brace, Christopher L.

    2014-01-01

    Image-guided thermal ablation is an evolving and growing treatment option for patients with malignant disease of multiple organ systems. Treatment indications have been expanding to include benign tumors as well. Specifically, the most prevalent indications to date have been in the liver (primary and metastatic disease, as well as benign tumors such as hemangiomas and adenomas), kidney (primarily renal cell carcinoma, but also benign tumors such as angiomyolipomas and oncocytomas), lung (primary and metastatic disease), and soft tissue and/or bone (primarily metastatic disease and osteoid osteomas). Each organ system has different underlying tissue characteristics, which can have profound effects on the resulting thermal changes and ablation zone. Understanding these issues is important for optimizing clinical results. In addition, thermal ablation technology has evolved rapidly during the past several decades, with substantial technical and procedural improvements that can help improve clinical outcomes and safety profiles. Staying up to date on these developments is challenging but critical because the physical properties underlying the different ablation modalities and the appropriate use of adjuncts will have a tremendous effect on treatment results. Ultimately, combining an understanding of the physical properties of the ablation modalities with an understanding of the thermal kinetics in tissue and using the most appropriate ablation modality for each patient are key to optimizing clinical outcomes. Suggested algorithms are described that will help physicians choose among the various ablation modalities for individual patients. ©RSNA, 2014 PMID:25208284

  9. Electrophysiological mapping and radiofrequency catheter ablation for ventricular tachycardia in a patient with peripartum cardiomyopathy.

    PubMed

    Tokuda, Michifumi; Stevenson, William G; Nagashima, Koichi; Rubin, David A

    2013-11-01

    A 38-year-old female with prior failed endocardial ablation for ventricular tachycardia (VT) was referred for further treatment. She had been diagnosed with peripartum cardiomyopathy 7 years before and had persistent left ventricular dysfunction with an ejection fraction of 20%. Epicardial voltage mapping showed extensive epicardial scar despite absence of endocardial scar. Five distinct VT morphologies were induced. Ablation was aided by electrogram characteristics, pace mapping, entrainment mapping, and establishing electrical inexcitability along areas of epicardial scar. After epicardial ablation no sustained VT was induced. She had been doing well without VT occurrence but died 1 year later unexpectedly at home. PMID:24102817

  10. Long-term Therapeutic Outcomes of Radiofrequency Ablation for Subcapsular versus Nonsubcapsular Hepatocellular Carcinoma: A Propensity Score Matched Study.

    PubMed

    Kang, Tae Wook; Lim, Hyo Keun; Lee, Min Woo; Kim, Young-Sun; Rhim, Hyunchul; Lee, Won Jae; Paik, Yong Han; Kim, Min Ji; Ahn, Joong Hyun

    2016-07-01

    Purpose To compare the long-term therapeutic outcomes of radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) in subcapsular versus nonsubcapsular locations by using propensity score matching. Materials and Methods RF ablation for subcapsular HCC is controversial because of a high risk of incomplete ablation or major complications. This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. Between April 2006 and December 2011, 508 consecutive patients (396 men, 112 women; age range, 30-80 years) with a single HCC (Barcelona Clinic Liver Cancer stage 0 or A) underwent ultrasonography-guided percutaneous RF ablation as a first-line treatment. The patients were divided into two groups according to tumor location: subcapsular (n = 227) and nonsubcapsular (n = 281). Subcapsular HCC was defined as an index tumor located within 0.1 cm of the liver capsule. The association of subcapsular location and therapeutic outcomes of RF ablation was evaluated, including (a) local tumor progression (LTP) by using a competing risk regression model and (b) overall survival (OS) by using a Cox proportional hazards model according to propensity score matched data. The major complication rates from both overall data and matched data were assessed. Results Matching yielded 163 matched pairs of patients. In the two matched groups, cumulative LTP rates were 18.8% and 20.9% at 3 and 5 years, respectively, in the subcapsular group and 13.2% and 16.0% in the nonsubcapsular group. Corresponding OS rates were 90.7% for 3 years and 83.2% for 5 years in the subcapsular group and 91.4% and 79.1%, respectively, in the nonsubcapsular group. Hazard ratios (HRs) for LTP (HR = 1.37, P = .244) and OS (HR = 0.86, P = .604) were not significantly different between the two matched groups. Additionally, differences in major complication rates were not significant between groups for the two sets of data (P > .05). Conclusion The

  11. The use of PET-MRI in the follow-up after radiofrequency- and microwave ablation of colorectal liver metastases

    PubMed Central

    2014-01-01

    Background Thermal ablation of colorectal liver metastases (CRLM) may result in local progression, which generally appear within a year of treatment. As the timely diagnosis of this progression allows potentially curative local treatment, an optimal follow-up imaging strategy is essential. PET-MRI is a one potential imaging modality, combining the advantages of PET and MRI. The aim of this study is evaluate fluorine-18 deoxyglucose positron emission tomography (FDG) PET-MRI as a modality for detection of local tumor progression during the first year following thermal ablation, as compared to the current standard, FDG PET-CT. The ability of FDG PET-MRI to detect new intrahepatic lesions, and the extent to which FDG PET-MRI alters clinical management, inter-observer variability and patient preference will also be included as secondary outcomes. Methods/Design Twenty patients undergoing treatment with radiofrequency or microwave ablation for (recurrent) CRLM will be included in this prospective trial. During the first year of follow-up, patients will be scanned at the VU University Medical Center at 3-monthly intervals using a 4-phase liver CT, FDG PET-CT and FDG PET-MRI. Patients treated with chemotherapy <6 weeks prior to scanning or with a contra-indication for MRI will be excluded. MRI will be performed using both whole body imaging (mDixon) and dedicated liver sequences, including diffusion-weighted imaging, T1 in-phase and opposed-phase, T2 and dynamic contrast-enhanced imaging. The results of all modalities will be scored by 4 individual reviewers and inter-observer agreement will be determined. The reference standard will be histology or clinical follow-up. A questionnaire regarding patients’ experience with both modalities will also be completed at the end of the follow-up year. Discussion Improved treatment options for local site recurrences following CRLM ablation mean that accurate post-ablation staging is becoming increasingly important. The

  12. Lung radiofrequency and microwave ablation: a review of indications, techniques and post-procedural imaging appearances

    PubMed Central

    Jennings, P E

    2015-01-01

    Lung ablation can be used to treat both primary and secondary thoracic malignancies. Evidence to support its use, particularly for metastases from colonic primary tumours, is now strong, with survival data in selected cases approaching that seen after surgery. Because of this, the use of ablative techniques (particularly thermal ablation) is growing and the Royal College of Radiologists predict that the number of patients who could benefit from such treatment may reach in excess of 5000 per year in the UK. Treatment is often limited to larger regional centres, and general radiologists often have limited awareness of the current indications and the techniques involved. Furthermore, radiologists without any prior experience are frequently expected to interpret post-treatment imaging, often performed in the context of acute complications, which have occurred after discharge. This review aims to provide an overview of the current indications for pulmonary ablation, together with the techniques involved and the range of post-procedural appearances. PMID:25465192

  13. PATH OPTIMIZATION AND CONTROL OF A SHAPE MEMORY ALLOY ACTUATED CATHETER FOR ENDOCARDIAL RADIOFREQUENCY ABLATION

    PubMed Central

    Wiest, Jennifer H.; Buckner, Gregory D.

    2014-01-01

    This paper introduces a real-time path optimization and control strategy for shape memory alloy (SMA) actuated cardiac ablation catheters, potentially enabling the creation of more precise lesions with reduced procedure times and improved patient outcomes. Catheter tip locations and orientations are optimized using parallel genetic algorithms to produce continuous ablation paths with near normal tissue contact through physician-specified points. A nonlinear multivariable control strategy is presented to compensate for SMA hysteresis, bandwidth limitations, and coupling between system inputs. Simulated and experimental results demonstrate efficient generation of ablation paths and optimal reference trajectories. Closed-loop control of the SMA-actuated catheter along optimized ablation paths is validated experimentally. PMID:25684857

  14. The effect of changes in patients’ body position on the back pain intensity and hemodynamic status during and after radiofrequency catheter ablation of cardiac dysrhythmias

    PubMed Central

    Haghshenas, Hajar; Mansoori, Parisa; Najafi, Saeed; Nikoo, Mohamad Hosein; Zare, Najaf; Jonoobi, Mitra

    2013-01-01

    Background: After radiofrequency catheter ablation of arrhythmias, patients have to bed rest for 4-6 h to prevent bleeding and hematoma. However, such a rest may cause back pain in the patients. The aim of this study was to determine the effects of continuous change in body position during and after the radiofrequency ablation on the back pain. Materials and Methods: In a quasi-experimental design 75 patients referring to university-affiliated hospitals were randomly assigned to a control group, receiving no change in body position, group A subjected to changes in body position during and after ablation, and group B subjected to changes in body position during ablation. The intensity of pain, blood pressure, heart rate, and extent of bleeding and hematoma were measured. Results: The groups were not significantly different in terms of demographic characteristics, blood pressure, heart rate, overall bleeding, or hematoma at the entry into the coronary care unit. While not significantly different from each other, the intensity of back pain between group A and B were significantly lower than that of group C. Compared to group C, group A and B had a significantly lower pain score up to 6 and 4 h after the procedure, respectively. Group B had a significantly higher pain score at 2, 4, and 6 h post ablation than group A. Conclusions: The findings show that changing the body position during and after the ablation procedure would reduce or prevent the back pain without increasing the chance of bleeding and hematoma. PMID:23983735

  15. Short-Term Effect of Percutaneous Bipolar Continuous Radiofrequency on Sacral Nerves in Patients Treated for Neurogenic Detrusor Overactivity After Spinal Cord Injury: A Randomized Controlled Feasibility Study

    PubMed Central

    Kim, Jin Hyun; Ahn, Sang Ho; Cho, Yun Woo; Kwak, Sang Gyu

    2015-01-01

    Objective To investigate the short-term effects of bipolar radiofrequency applied to sacral nerves to treat neurogenic detrusor overactivity in patients with spinal cord injury. Methods Ten patients with spinal cord injury with neurogenic detrusor overactivity were recruited. These subjects were randomized to two groups: intervention (n=5) and control (n=5), members of which received conventional treatment. Voiding diary, International Consultation on Incontinence Questionnaire (ICIQ) and the urinary incontinence quality of life scale (IQOL) data were obtained and an urodynamic study (UDS) was performed before and after intervention. In the intervention group, percutaneous bipolar continuous radiofrequency (CRF) was performed on both the S2 and S3 nerves in each patient. Results In a comparison of daily frequency and number of urinary incontinence and ICIQ and IQOL scores at baseline and at 1 and 3 months after intervention, all variables achieved a significant effect for time (p<0.05). Regarding UDS parameters, pre/post intervention differences between baseline and 3-month post-intervention for volume at maximal detrusor pressure during filling and reflex detrusor volume at first contraction were significantly different between the two groups (p<0.05). However, pre/post intervention differences in maximum cystometric capacity and maximum detrusor pressure during filling were not significant between the two groups (p>0.05). Conclusion Percutaneous bipolar CRF applied to sacral nerves might be an effective therapy for neurogenic overactive bladder that reduces urinary incontinence and improves quality of life. PMID:26605169

  16. Computed Tomography-guided Radiofrequency Ablation for Sub-diaphragm Hepatocellular Carcinoma: Safety and Efficacy of Inducing an Artificial Pneumothorax.

    PubMed

    Fujiwara, Hiroyasu; Arai, Yasuaki; Ishii, Hiroaki; Kanazawa, Susumu

    2016-06-01

    We retrospectively evaluated the safety and efficacy of artificial pneumothorax induction to perform computed tomography (CT)-guided radiofrequency ablation (RFA) for sub-diaphragm hepatocellular carcinomas (HCCs). From June 2008 to October 2010 at our institution, 19 HCCs (16 patients) were treated using CT-guided RFA after artificial pneumothorax induction. A 23-G needle was inserted into the liver surface at a site of 2 connected pleurae without lung tissue. After a small amount of air was injected, the pleural space widened, creating a small pneumothorax. Additional air was insufflated via a newly inserted 18-G cannula to raise the lung away from the planned puncture line for RFA. The electrode was then advanced transthoracically. Ablation was performed using a cool-tip electrode with manual impedance control mode. The injected air was then aspirated as much as possible. Artificial pneumothorax was successfully induced in all cases. The average total volume of injected air in each case was 238ml. No artificial pneumothorax-related complication occurred; lung injury occurred in one case during RF electrode insertion. No local progression occurred during follow-up. Recurring HCCs were observed in eight patients. Artificial pneumothorax induction is safe and effective for CT-guided RFA of sub-diaphragm HCCs, which are difficult to locate on US. PMID:27339208

  17. Radiofrequency ablation without the use of fluoroscopy – in what kind of patients is it feasible?

    PubMed Central

    Gawrysiak, Marcin; Piątkowska, Agnieszka; Lodziński, Piotr; Kiliszek, Marek; Małkowska, Sylwia; Zaczek, Rajmund; Piątkowski, Radosław; Opolski, Grzegorz; Kozłowski, Dariusz

    2013-01-01

    Introduction The aim of the study was to describe the experience in performing ablation without fluoroscopy. Material and methods From 575 ablation procedures with CARTO performed in the period 2003–2008, 108 (42 M; age 40 ±16 years) were done without fluoroscopy. One patient had ablation using the Localisa system. There was one man with thrombocytopenia and two pregnant women. Results Right ventricular (RV) outflow tract arrhythmias and other RV arrhythmias were noted in 38 patients (35%) and 17 patients (15%), respectively. There were 5 (4.6%) left ventricular (LV) outflow tract arrhythmias and 19 (17.5%) other LV tachycardias; right accessory pathways in 17 patients (20%), in the middle cardiac vein in 1, Mahaim fibres in 1, and 3 cases of permanent junctional reciprocating tachycardias. One patient with CRT had AV node ablation (Localisa). In 3 patients there were also other arrhythmias treated: slow AV nodal pathway, typical flutter isthmus and right atrial tachycardia. In 2004, 1/96 CARTO procedures was done without fluoroscopy, in 2006 2/97, in 2007 19 (2 in LV) of 93, in 2008 87 (22 in LV) of 204. The percentage of ablations without fluoroscopy in every hundred CARTO procedures was: 1%, 1%, 8%, 23%, 46%, 28% (mean 18%). There were no procedure-related complications. Conclusions It is feasible to perform ablations within both right and left sides of the heart without fluoroscopy. The number and type of non-fluoroscopic procedures depends on the operator's experience. Pregnant patients, with malignant history or with hematologic diseases should be ablated without fluoroscopy in centres that specialise in these kinds of procedures. PMID:24273563

  18. Radiofrequency ablation of the basivertebral nerve as potential treatment of back pain: pathologic assessment in an ovine model (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Hoopes, P. J.; Eskey, Cliff J.; Attawia, Mohammed; Patel, Samit J.; Ryan, T. P.; Pellegrino, Richard; Bergeron, Jeffrey A.

    2005-04-01

    Pathological involvement of the basivertebral nerve (BVN), an intraosseous vertebral nerve, may play a significant role in some forms of back pain. This study was designed to assess the feasibility and effects of thermal ablation of the lumbar basivertebral nerve in mature sheep. Sixteen adult female sheep weighing 65-80 kg were anesthetized and positioned for ventral recumbent surgery. Under fluoroscopic guidance, two bilarterally oposed 5mm active length rediofrequency (RF) electrodes (1.65mm diameter were perfutaneously placed in select lumbar vertebrae at a relative angle of 70 degrees with a 5 mm tip separation. The elctrodes were advanced to the region of the vertebral bodies which contained the BVN. A thermal dose of 95° C/720 seconds was administered. Animals were survived for 2, 14, 90, or 180 days post-treatment. Clinical, radiologic and pathologic investigations were performed to determine the effect of the heat on the BVN and associated tissues. Thermal damage to the basivertebral neurovascular bundle was characterized by early hemorrhage and necrosis, followed by inflammation and fibrosis. Although there wasa significant revascularization of the treated bone marow regions, there was no evidence of basivertebral nerve survival or regeneration regeneration. In addition to ablation of teh basivertebral nerovascular bundle, the areas receiving the greatest treatment demonstrated initial mild local osteolysis and demineralization of the vertebral body bone and regional depopulation of the vertebral bone marrow cellular elements. Significant bone remodeling in the affected areas had begun by 14 days post-treatment. Bone remodeling was characterized by conventional osteoblast proliferation, osteoid deposition, and mineralization. This study demonstrated the ability to accurately, reproducibly, and safely ablate the basivertebral nerve and neurovascular bundle in mature sheep using a fluoroscopically guided percutaneously delivered radiofrequency technique.

  19. Lung Radiofrequency Ablation for the Treatment of Unresectable Recurrent Non-Small-Cell Lung Cancer After Surgical Intervention

    SciTech Connect

    Kodama, Hiroshi Yamakado, Koichiro; Takaki, Haruyuki; Kashima, Masataka; Uraki, Junji; Nakatsuka, Atsuhiro; Takao, Motoshi; Taguchi, Osamu; Yamada, Tomomi; Takeda, Kan

    2012-06-15

    Purpose: A retrospective evaluation was done of clinical utility of lung radiofrequency (RF) ablation in recurrent non-small-cell lung cancer (NSCLC) after surgical intervention. Methods: During May 2003 to October 2010, 44 consecutive patients (26 male and 18 female) received curative lung RF ablation for 51 recurrent NSCLC (mean diameter 1.7 {+-} 0.9 cm, range 0.6 to 4.0) after surgical intervention. Safety, tumor progression rate, overall survival, and recurrence-free survival were evaluated. Prognostic factors were evaluated in multivariate analysis. Results: A total of 55 lung RF sessions were performed. Pneumothorax requiring pluerosclerosis (n = 2) and surgical suture (n = 1) were the only grade 3 or 4 adverse events (5.5%, 3 of 55). During mean follow-up of 28.6 {+-} 20.3 months (range 1 to 98), local tumor progression was found in 5 patients (11.4%, 5 of 44). The 1-, 3-, and 5-year overall survival rates were 97.7, 72.9, and 55.7%, respectively. The 1- and 3-year recurrence-free survival rates were 76.7 and 41.1%, respectively. Tumor size and sex were independent significant prognostic factors in multivariate analysis. The 5-year survival rates were 73.3% in 18 women and 60.5% in 38 patients who had small tumors measuring {<=}3 cm. Conclusion: Our results suggest that lung RF ablation is a safe and useful therapeutic option for obtaining long-term survival in treated patients.

  20. Factors related to sinus rhythm at discharge after radiofrequency ablation of permanent atrial fibrillation in patients undergoing mitral valve surgery.

    PubMed

    Rostagno, Carlo; Gelsomino, Sandro; Capecchi, Irene; Rossi, Alessandra; Montesi, Gian Franco; Stefàno, Pier Luigi

    2016-04-01

    Late recovery of sinus rhythm is unusual in patients with permanent AF treated by (radiofrequency) RF maze procedure during mitral valve surgery. Identification of clinical and instrumental preoperative factors predictive of early success of RF ablation in patients with permanent AF undergoing mitral valve surgery may improve selection of subjects to obtain long-term results. Hundred and thirty consecutive patients with permanent AF and mitral valve disease underwent modified RF maze procedure during concomitant mitral valve surgery. Rheumatic valve disease (61 pts) and mitral valve prolapse (41 pts) were the more common aetiology of valve abnormalities. Mitral valve replacement was performed in 54 % of patients and mitral valve repair in the remaining 46 %. Four patients died after surgery. At discharge, 87 patients (69 %) were in sinus rhythm (group 1) and 43 patients in AF persisted (group 2). At an average 24-month follow-up, sinus rhythm was present in 67 % of patients, and 33 % were in atrial fibrillation. In this period, late recovery of sinus rhythm was observed only in five patients, while eight discharged in sinus rhythm developed again atrial fibrillation. Among preoperative parameters at univariate analysis female sex, atrial fibrillation >24 months, left atrial diameter >54 mm, left atrial area >24 cm(2), rheumatic valve disease and NYHA class were associated with persistence of AF. At Cox regression multivariate analysis, increased left atrial area (OR 1.07 per unit increase-95 % CI 1.01-1.131) and rheumatic aetiology of valve disease (OR 4.52, 95 % CI 1.65-12.4) were associated with persistence of AF at hospital discharge. Persistence of AF after RF ablation in patients undergoing mitral valve surgery is related to aetiology, e.g. rheumatic valve disease, and to increasing left atrial diameter. Due to low rate of late recovery of sinus rhythm, indication to RF ablation associated with MV surgery should be carefully considered in patients with large

  1. Radiofrequency Ablation Assisted by Real-Time Virtual Sonography and CT for Hepatocellular Carcinoma Undetectable by Conventional Sonography

    SciTech Connect

    Nakai, Motoki Sato, Morio; Sahara, Shinya; Takasaka, Isao; Kawai, Nobuyuki; Minamiguchi, Hiroki; Tanihata, Hirohiko; Kimura, Masashi; Takeuchi, Nozomu

    2009-01-15

    Real-time virtual sonography (RVS) is a diagnostic imaging support system, which provides the same cross-sectional multiplanar reconstruction images as ultrasound images on the same monitor screen in real time. The purpose of this study was to evaluate radiofrequency ablation (RFA) assisted by RVS and CT for hepatocellular carcinoma (HCC) undetectable with conventional sonography. Subjects were 20 patients with 20 HCC nodules not detected by conventional sonography but detectable by CT or MRI. All patients had hepatitis C-induced liver cirrhosis; there were 13 males and 7 females aged 55-81 years (mean, 69.3 years). RFA was performed in the CT room, and the tumor was punctured with the assistance of RVS. CT was performed immediately after puncture, and ablation was performed after confirming that the needle had been inserted into the tumor precisely. The mean number of punctures and success rates of the first puncture were evaluated. Treatment effects were evaluated with dynamic CT every 3 months after RFA. RFA was technically feasible and local tumor control was achieved in all patients. The mean number of punctures was 1.1, and the success rate of the first puncture was 90.0%. This method enabled safe ablation without complications. The mean follow-up period was 13.5 month (range, 9-18 months). No local recurrence was observed at the follow-up points. In conclusion, RFA assisted by RVS and CT is a safe and efficacious method of treatment for HCC undetectable by conventional sonography.

  2. Radiofrequency Catheter Ablation of Accessory Atrioventricular Pathways in Infants and Toddlers ≤ 15 kg.

    PubMed

    Backhoff, David; Klehs, Sophia; Müller, Matthias J; Schneider, Heike; Kriebel, Thomas; Paul, Thomas; Krause, Ulrich

    2016-06-01

    Accessory atrioventricular pathways (AP) are the most common substrate for paroxysmal supraventricular tachycardia in infants and small children. Up-to-date data on AP ablation in infants and small children are limited. The aim of the present study was to gain additional insight into radiofrequency (RF) catheter ablation of AP in infants and toddlers focusing on efficacy and safety in patients with a body weight of ≤ 15 kg. Since 10/2002, RF ablation of AP was performed in 281 children in our institution. Indications, procedural data as well as success and complication rates in children with a body weight ≤ 15 kg (n = 22) were compared with children > 15 kg (n = 259). Prevalence of structural heart anomalies was significantly higher among children ≤ 15 kg (27 vs. 5.7 %; p = 0.001). Procedure duration (median 262 vs. 177 min; p = 0.001) and fluoroscopy time (median 20.6 vs. 14.0 min; p = 0.007) were significantly longer among patients ≤ 15 kg. Procedural success rate did not differ significantly between the two groups (82 vs. 90 %). More RF lesions were required for AP ablation in the smaller patients (median 12 vs. 7; p = 0.019). Major complication rate was significantly higher in children ≤ 15 kg (9 vs. 1.1 %; p = 0.05) with femoral vessel occlusion being the only major adverse event in patients ≤ 15 kg. Catheter ablation of AP in children was effective irrespective of body weight. In children ≤ 15 kg, however, procedures were more challenging and time-consuming. Complication rate and number of RF lesions in smaller children were higher when compared to older children. PMID:26961570

  3. Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas Adjacent to the Gallbladder with Internally Cooled Electrodes: Assessment of Safety and Therapeutic Efficacy

    PubMed Central

    Kim, Sang Won; Park, Mihyun; Kim, Heejung; Kim, Young-sun; Choi, Dongil; Lim, Hyo K.

    2009-01-01

    Objective The objective of this study was to evaluate the safety and therapeutic efficacy of percutaneous radiofrequency (RF) ablation for the treatment of hepatocellular carcinomas (HCCs) adjacent to the gallbladder with the use of internally cooled electrodes. Materials and Methods We retrospectively assessed 45 patients with 46 HCCs (mean size, 2.2 cm) adjacent to the gallbladder (≤1.0 cm) treated with RF ablation using an internally cooled electrode system. An electrode was inserted into the tumor either parallel (n = 38) or perpendicular (n = 8) to the gallbladder wall. The safety and therapeutic efficacy of the procedures were assessed with clinical and imaging follow-up examinations. Follow-up with the use of CT ranged from four to 45 months (mean, 19 months). The association between variables (electrode direction, electrode type, tumor size, tumor location, lobar location) and the presence of a residual tumor or local tumor progression was also analyzed. Results There were no major complications and minor complications were noted in three patients (7%) including one case of vasovagal syncope and two cases of bilomas. Wall thickening of the gallbladder adjacent to the RF ablation zone was noted in 14 patients (41%) as determined on immediate follow-up CT imaging. Wall thickening showed complete disappearance on subsequent follow-up CT imaging. The primary technique effectiveness rate was 96% (44/46) based on one-month follow-up CT imaging. Local tumor progression was noted in six (14%) of 44 completely ablated tumors during the follow-up period. The direction of electrode insertion (perpendicular), tumor size (≥3 cm) and tumor location (a tumor that abutted the gallbladder) were associated with an increased risk of early incomplete treatment. No variable was significantly associated with local tumor progression. Conclusion Percutaneous RF ablation of HCCs adjacent to the gallbladder using an internally cooled electrode is a safe and effective treatment

  4. Novel P Wave Indices to Predict Atrial Fibrillation Recurrence After Radiofrequency Ablation for Paroxysmal Atrial Fibrillation.

    PubMed

    Hu, Xiaoliang; Jiang, Jingzhou; Ma, Yuedong; Tang, Anli

    2016-01-01

    BACKGROUND Circumferential pulmonary vein isolation (CPVI) is a widely used treatment for paroxysmal atrial fibrillation (AF). Several P wave duration (PWD) parameters have been suggested to predict post-ablation recurrence, but their use remains controversial. This study aimed to identify novel P wave indices that predict post-ablation AF recurrence. MATERIAL AND METHODS We selected 171 consecutive patients undergoing CPVI for paroxysmal AF. Electrocardiography (ECG) recordings were obtained at the beginning and the end of ablation. PWD was measured in all 12 leads. The PWD variation was calculated by subtracting the pre-ablation PWD from the post-ablation PWD. RESULTS PWD was significantly shortened in leads II, III, aVF, and V1 after ablation. During a mean follow-up of 19.96±4.32 months, AF recurrence occurred in 32 (18.7%) patients. No significant differences in baseline characteristics or pre- or post-ablation PWD were observed between the AF recurrence and non-recurrence groups. Patients with AF recurrence exhibited a smaller PWD variation in leads II (1.21(-0.56, 2.40) vs. -5.77(-9.10, -4.06) ms, P<0.001), III (-5.92(-9.87, 3.27) vs. -9.44(-11.89, -5.57) ms, P=0.001) and V1 (-4.43(-6.64, -3.13) vs. -6.33(-8.19,-4.59) ms, P=0.003). Multivariable logistic regression analysis demonstrated that smaller PWD variations in lead II and III were independent risk factors for AF recurrence. PWD variation ≥-2.21 ms in lead II displayed the highest combined sensitivity and specificity (85.29% and 83.94%, respectively) for predicting post-ablation AF recurrence. A PWD variation ≥0 ms displayed the best practical value in predicting AF recurrence. CONCLUSIONS PWD variation in lead II is an effective predictor of post-ablation AF recurrence. PMID:27450644

  5. Novel P Wave Indices to Predict Atrial Fibrillation Recurrence After Radiofrequency Ablation for Paroxysmal Atrial Fibrillation

    PubMed Central

    Hu, Xiaoliang; Jiang, Jingzhou; Ma, Yuedong; Tang, Anli

    2016-01-01

    Background Circumferential pulmonary vein isolation (CPVI) is a widely used treatment for paroxysmal atrial fibrillation (AF). Several P wave duration (PWD) parameters have been suggested to predict post-ablation recurrence, but their use remains controversial. This study aimed to identify novel P wave indices that predict post-ablation AF recurrence. Material/Methods We selected 171 consecutive patients undergoing CPVI for paroxysmal AF. Electrocardiography (ECG) recordings were obtained at the beginning and the end of ablation. PWD was measured in all 12 leads. The PWD variation was calculated by subtracting the pre-ablation PWD from the post-ablation PWD. Results PWD was significantly shortened in leads II, III, aVF, and V1 after ablation. During a mean follow-up of 19.96±4.32 months, AF recurrence occurred in 32 (18.7%) patients. No significant differences in baseline characteristics or pre- or post-ablation PWD were observed between the AF recurrence and non-recurrence groups. Patients with AF recurrence exhibited a smaller PWD variation in leads II (1.21(−0.56, 2.40) vs. −5.77(−9.10, −4.06) ms, P<0.001), III (−5.92(−9.87, 3.27) vs. −9.44(−11.89, −5.57) ms, P=0.001) and V1 (−4.43(−6.64, −3.13) vs. −6.33(−8.19,−4.59) ms, P=0.003). Multivariable logistic regression analysis demonstrated that smaller PWD variations in lead II and III were independent risk factors for AF recurrence. PWD variation ≥−2.21 ms in lead II displayed the highest combined sensitivity and specificity (85.29% and 83.94%, respectively) for predicting post-ablation AF recurrence. A PWD variation ≥0 ms displayed the best practical value in predicting AF recurrence. Conclusions PWD variation in lead II is an effective predictor of post-ablation AF recurrence. PMID:27450644

  6. Radiofrequency catheter ablation for dyssynchrony-induced dilated cardiomyopathy in an infant.

    PubMed

    Kwon, Elena N; Carter, Kerri A; Kanter, Ronald J

    2014-01-01

    The relationship between accessory pathway-mediated ventricular preexcitation and left ventricular dyssynchrony-induced dysfunction has been described in patients with Wolff-Parkinson-White (WPW) syndrome in the absence of sustained supraventricular tachycardia (SVT). Supraventricular tachycardia in infants is usually successfully suppressed with antiarrhythmic medications, but catheter ablation has ultimately been required as definitive treatment in medically resistant cases. Catheter ablation has not been described in young infants for dyssynchrony-related dilated cardiomyopathy in the absence of SVT. We describe a case of an infant with WPW who did not have sustained supraventricular tachycardia, but who developed rapid progression of ventricular dysfunction after birth. Preexcitation could not be medically suppressed but was successfully ablated. This was followed by complete resolution of ventricular dysfunction within 2 months. PMID:23902593

  7. Long-Term Outcome of a Hepatocellular Carcinoma 71/2 Years After Surgery and Repeated Radiofrequency Ablation: Case Report and Review of the Literature

    SciTech Connect

    Thanos, L. Mylona, S.; Nikita, A.; Ptohis, N.; Kelekis, D.A.

    2007-04-15

    An interesting case is presented of a 78-year-old patient with cirrhosis who was managed with combined treatment (surgery and radiofrequency (RF) ablation) for hepatocellular carcinoma (HCC) and has survived for 71/2 years. Elevation of the {alpha}-FP (alpha-fetoprotein) levels was noted 2 years after surgery. CT demonstrated two lesions: one central at the remaining right liver lobe, and the other at the excision site. Biopsy of the lesions confirmed the diagnosis of HCC for both of them. RF ablation of these two lesions was performed in one session with technical success. Four and a half years after the first RF ablation a new recurrence was demonstrated at the CT follow-up control. RF ablation was again applied successfully. The imaging findings and the therapeutic percutaneous management of this patient along with the natural course of HCC and its recurrence are discussed, and the literature concerning risk factors is reviewed.

  8. Use of Intra-Arterial Carbon-Dioxide-Enhanced Ultrasonography for Guidance of Radiofrequency Ablation and Transcatheter Arterial Chemoembolization in Hepatocellular Carcinoma

    SciTech Connect

    Ohmoto, Kenji Yoshioka, Naoko; Tomiyama, Yasuyuki; Shibata, Norikuni; Kawase, Tomoya; Yoshida, Koji; Kuboki, Makoto; Yamamoto, Shinichiro

    2006-12-15

    A 73-year-old man with hepatitis-C-related cirrhosis and an elevated alpha-fetoprotein level and tumor in segment 3 of his liver was referred for interventional radiologic treatment. He was not a candidate for surgical resection due to impaired liver function and his personal preferences. On conventional ultrasonography no lesion could be detected, but the tumor was clearly depicted by intra-arterial carbon-dioxide-enhanced ultrasonography. Radiofrequency ablation was performed safely and accurately under the guidance of carbon-dioxide-enhanced ultrasonography. By concomitant performance of transcatheter arterial chemoembolization with radiofrequency ablation, extensive necrosis was obtained and adequate tumor volume reduction achieved with only one treatment session.

  9. Increased Duration of Heating Boosts Local Drug Deposition during Radiofrequency Ablation in Combination with Thermally Sensitive Liposomes (ThermoDox) in a Porcine Model

    PubMed Central

    Swenson, Christine E.; Haemmerich, Dieter; Maul, Donald H.; Knox, Bridget; Ehrhart, Nicole; Reed, Robert A.

    2015-01-01

    Introduction Radiofrequency ablation (RFA) is used for the local treatment of liver cancer. RFA is effective for small (<3cm) tumors, but for tumors > 3 cm, there is a tendency to leave viable tumor cells in the margins or clefts of overlapping ablation zones. This increases the possibility of incomplete ablation or local recurrence. Lyso-Thermosensitive Liposomal Doxorubicin (LTLD), is a thermally sensitive liposomal doxorubicin formulation for intravenous administration, that rapidly releases its drug content when exposed to temperatures >40°C. When used with RFA, LTLD releases its doxorubicin in the vasculature around the zone of ablation-induced tumor cell necrosis, killing micrometastases in the ablation margin. This may reduce recurrence and be more effective than thermal ablation alone. Purpose The purpose of this study was to optimize the RFA procedure used in combination with LTLD to maximize the local deposition of doxorubicin in a swine liver model. Pigs were anaesthetized and the liver was surgically exposed. Each pig received a single, 50 mg/m2 dose of the clinical LTLD formulation (ThermoDox®). Subsequently, ablations were performed with either 1, 3 or 6 sequential, overlapping needle insertions in the left medial lobe with total ablation time of 15, 45 or 90 minutes respectively. Two different RFA generators and probes were evaluated. After the final ablation, the ablation zone (plus 3 cm margin) was dissected out and examined for doxorubicin concentration by LC/MS and fluorescence. Conclusion The mean Cmax of plasma total doxorubicin was 26.5 μg/ml at the end of the infusion. Overall, increased heat time from 15 to 45 to 90 minutes shows an increase in both the amount of doxorubicin deposited (up to ~100 μg/g) and the width of the ablation target margin to which doxorubicin is delivered as determined by tissue homogenization and LC/MS detection of doxorubicin and by fluorescent imaging of tissues. PMID:26431204

  10. The synergistic effects of radiofrequency ablation (RFA) with glycated chitosan for inhibiting the metastasis of breast cancer

    NASA Astrophysics Data System (ADS)

    Chiu, Hsin-Yu; Leu, Jyh-Der; Chen, Wei R.; Lee, Yi-Jang

    2016-03-01

    Breast cancer is increasing with years in Taiwan because of dietary style, life behavior and several social-physiological factors. According to the record of Bureau of Health Promotion in Taiwan, the incidence of breast cancer is top one, and the mortality of that is top one cancer type in women. Compared with USA, most of breast cancer cases found in Taiwanese women have reached to stage 2 or 3. Current therapeutic strategies for breast cancer include surgery, radiation therapy, chemotherapy, hormone therapy and targeted therapy. However, these methods used for curing the late-stage breast cancer remains rare. Because the metastasis is the major problem of late-stage breast cancer, it is of interest to investigate whether a systemic therapy can reduce the symptoms of cancer. The immunotherapy, particularly an induction of autoimmune system, is probably important for the treatment of late-stage breast cancer. Glycated chitosan (GC) is derived from chitosan, a linear polysaccharide composed of D-glucosamine and N-acetyl-D-glucosamine through β-(1-4) linkage. Several lines of evidence have shown that GC is an immunoadjuvant that can target on primary and metastatic tumors formed in animal and human patients. In our previous data, GC was demonstrated to decrease the motility and invasion of mammalian breast cancer cells in vitro and in vivo. Radiofrequency ablation (RFA) is dependent on a small generator that delivers high frequency alternating electric current directly to burn a tumor lesion. Therefore, the temperature may reach up to above 60 °C. In this study, we used 4T1 mouse breast cancer cell that is the approximately equal to stage 4 of human breast cancer. And triple modality reporter gene (3R) was delivered into the cells using transfected piggyBac, a transposable element for observation of tumor growth and metastasis in vivo. Data showed that growth and metastasis of tumors smaller than 500mm3 were entirely suppressed by RFA-GC combination treatment

  11. A Comparison of Direct Heating During Radiofrequency and Microwave Ablation in Ex Vivo Liver

    SciTech Connect

    Andreano, Anita; Brace, Christopher L.

    2013-04-15

    This study was designed to determine the magnitude and spatial distribution of temperature elevations when using 480 kHz RF and 2.45 GHz microwave energy in ex vivo liver models. A total of 60 heating cycles (20 s at 90 W) were performed in normal, RF-ablated, and microwave-ablated liver tissues (n = 10 RF and n = 10 microwave in each tissue type). Heating cycles were performed using a 480-kHz generator and 3-cm cooled-tip electrode (RF) or a 2.45-GHz generator and 14-gauge monopole (microwave) and were designed to isolate direct heating from each energy type. Tissue temperatures were measured by using fiberoptic thermosensors 5, 10, and 15 mm radially from the ablation applicator at the depth of maximal heating. Power delivered, sensor location, heating rates, and maximal temperatures were compared using mixed effects regression models. No significant differences were noted in mean power delivered or thermosensor locations between RF and microwave heating groups (P > 0.05). Microwaves produced significantly more rapid heating than RF at 5, 10, and 15 mm in normal tissue (3.0 vs. 0.73, 0.85 vs. 0.21, and 0.17 vs. 0.09 Degree-Sign C/s; P < 0.05); and at 5 and 10 mm in ablated tissues (2.3 {+-} 1.4 vs. 0.7 {+-} 0.3, 0.5 {+-} 0.3 vs. 0.2 {+-} 0 Degree-Sign C/s, P < 0.05). The radial depth of heating was {approx}5 mm greater for microwaves than RF. Direct heating obtained with 2.45-GHz microwave energy using a single needle-like applicator is faster and covers a larger volume of tissue than 480-kHz RF energy.

  12. Pretreatment Evaluation with Contrast-Enhanced Ultrasonography for Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas with Poor Conspicuity on Conventional Ultrasonography

    PubMed Central

    Kim, Ah Yeong; Rhim, Hyunchul; Cha, Dong Ik; Choi, Dongil; Kim, Young-sun; Lim, Hyo Keun; Cho, Seong Whi

    2013-01-01

    Objective To determine whether pretreatment evaluation with contrast-enhanced ultrasonography (CEUS) is effective for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with poor conspicuity on conventional ultrasonography (US). Materials and Methods This retrospective study was approved by the institutional review board and informed consent was waived. From June 2008 to July 2011, 82 patients having HCCs (1.2 ± 0.4 cm) with poor conspicuity on planning US for RFA were evaluated with CEUS prior to percutaneous RFA. We analyzed our database, radiologic reports, and US images in order to determine whether the location of HCC candidates on planning US coincide with that on CEUS. To avoid incomplete ablation, percutaneous RFA was performed only when HCC nodules were identified on CEUS. The rate of technical success was assessed. The cumulative rate of local tumor progression was estimated with the use of the Kaplan-Meier method (mean follow-up: 24.0 ± 13.0 months). Results Among 82 patients, 73 (89%) HCCs were identified on CEUS, whereas 9 (11%) were not. Of 73 identifiable HCCs on CEUS, the location of HCC on planning US corresponded with that on CEUS in 64 (87.7%), whereas the location did not correspond in 9 (12.3%) HCCs. Technical success was achieved for all 73 identifiable HCCs on CEUS in a single (n = 72) or two (n = 1) RFA sessions. Cumulative rates of local tumor progression were estimated as 1.9% and 15.4% at 1 and 3 years, respectively. Conclusion Pretreatment evaluation with CEUS is effective for percutaneous RFA of HCCs with poor conspicuity on conventional US. PMID:24043968

  13. A phase I/pilot study of radiofrequency ablation for the treatment of recurrent pediatric solid tumors

    PubMed Central

    Hoffer, Fredric A.; Daw, Najat C.; Xiong, Xiaoping; Anghelescu, Doralina; Krasin, Matthew; Yan, Xiaowei; Davidoff, Andrew M.; Furman, Wayne L.; Rodriguez-Galindo, Carlos; Spunt, Sheri L.

    2010-01-01

    Background This prospective study was designed to be the first to evaluate the toxicity of radiofrequency ablation (RFA) in patients with recurrent pediatric solid tumors. Methods From 2003 through 2008, we conducted a phase I/pilot study of RFA for recurrent pediatric solid tumors. A multidisciplinary cancer management team selected appropriate candidates for the study. Imaging-guided RFA was performed percutaneously. Repeat RFA was performed for recurrences when appropriate. Toxicity and imaging response was assessed at 1 and 3 months prospectively. Accrual stopped in 2006 and data collection stopped in 2008. Results Sixteen patients (age 4 – 33 years, median 15 years) and 56 tumor sites were treated in 37 RFA sessions including 38 pulmonary, 11 musculoskeletal, and 7 hepatic lesions (82 lesion-treatments). Post-procedural pain was moderate (median 5 on a scale from 1 to 10) and lasted a median of 9 days. Prolonged hospitalization (beyond 1 day) occurred 17 times (range 2–25 days, median 3 days). Hypoxia supported by supplemental oxygen occurred in 8 of 16 patients and resolved within one month after each RFA. No patient had tumor lysis syndrome but myoglobinuria/hemoglobinuria occurred in 6 of 16 patients all without renal damage. Serious complications from pulmonary RFA included two diaphragmatic hernias. Twenty-four of 82 (29%) lesions imaged remained ablated at the end of the study. Conclusion The toxicity from RFA of recurrent pediatric solid tumors is real but limited and RFA may offer a local tumor control alternative in carefully selected cases. PMID:19180637

  14. Immune Adjuvant Activity of Pre-Resectional Radiofrequency Ablation Protects against Local and Systemic Recurrence in Aggressive Murine Colorectal Cancer

    PubMed Central

    Ito, Fumito; Ku, Amy W.; Bucsek, Mark J.; Muhitch, Jason B.; Vardam-Kaur, Trupti; Kim, Minhyung; Fisher, Daniel T.; Camoriano, Marta; Khoury, Thaer; Skitzki, Joseph J.; Gollnick, Sandra O.; Evans, Sharon S.

    2015-01-01

    Purpose While surgical resection is a cornerstone of cancer treatment, local and distant recurrences continue to adversely affect outcome in a significant proportion of patients. Evidence that an alternative debulking strategy involving radiofrequency ablation (RFA) induces antitumor immunity prompted the current investigation of the efficacy of performing RFA prior to surgical resection (pre-resectional RFA) in a preclinical mouse model. Experimental Design Therapeutic efficacy and systemic immune responses were assessed following pre-resectional RFA treatment of murine CT26 colon adenocarcinoma. Results Treatment with pre-resectional RFA significantly delayed tumor growth and improved overall survival compared to sham surgery, RFA, or resection alone. Mice in the pre-resectional RFA group that achieved a complete response demonstrated durable antitumor immunity upon tumor re-challenge. Failure to achieve a therapeutic benefit in immunodeficient mice confirmed that tumor control by pre-resectional RFA depends on an intact adaptive immune response rather than changes in physical parameters that make ablated tumors more amenable to a complete surgical excision. RFA causes a marked increase in intratumoral CD8+ T lymphocyte infiltration, thus substantially enhancing the ratio of CD8+ effector T cells: FoxP3+ regulatory T cells. Importantly, pre-resectional RFA significantly increases the number of antigen-specific CD8+ T cells within the tumor microenvironment and tumor-draining lymph node but had no impact on infiltration by myeloid-derived suppressor cells, M1 macrophages or M2 macrophages at tumor sites or in peripheral lymphoid organs (i.e., spleen). Finally, pre-resectional RFA of primary tumors delayed growth of distant tumors through a mechanism that depends on systemic CD8+ T cell-mediated antitumor immunity. Conclusion Improved survival and antitumor systemic immunity elicited by pre-resectional RFA support the translational potential of this neoadjuvant

  15. Radiofrequency Ablated Lesion in the Normal Porcine Lung: Long-Term Follow-Up with MRI and Pathology

    SciTech Connect

    Oyama, Yoshimasa E-mail: yoshimasa03155@ych.or.jp; Nakamura, Kenji; Matsuoka, Toshiyuki; Toyoshima, Masami; Yamamoto, Akira; Okuma, Tomohisa; Ikura, Yoshihiro; Ueda, Makiko; Inoue, Yuichi

    2005-04-15

    Purpose. To evaluate the effectiveness of magnetic resonance imaging (MRI) in reflecting histopathologic changes after radiofrequency ablation (RFA) to the lung and to assess accurately the extent of tissue necrosis for evaluating untreated lesions. Methods. Percutaneous RFA was performed on 72 lung regions in 12 pigs under computed tomographic guidance. After performing MRI, the animals were divided into three experimental phases: in the acute phase, 4 pigs were killed immediately after the procedure; in the subacute phase, 4 pigs were killed at 1 week; and in the chronic phases, 2 pigs were killed at 4 and 8 weeks after the procedure, respectively. MRI-histopathologic correlation was performed. Results. In the acute phase, the inner zone showed hypointensity on T2-weighted images and isointensity on T1-weighted images, with a lack of enhancement on contrast-enhanced T1-weighted images, representing early changes in coagulative necrosis on histopathologic examination. The outer zone showed hyperintensity on T2-weighted images and isointensity on T1-weighted images, with ring-like enhancement on contrast-enhanced T1-weighted images. The histopathologic section showed alveolar fluid collections and congestion. In the subacute phase the MR zone pattern was essentially similar to that of the acute phase, but the ablated lesion showed extensive coagulative necrosis with a fibrovascular rim on histopathologic examination. In the chronic phase, there was no change in the zone pattern on MRI. The lesions showed gradual resorption of coagulative necrosis. The area of coagulative necrosis correlated closely with the histopathologic size (p < 0.05). Conclusions. MRI effectively visualized the histopathologic changes after RFA and accurately determined the extent of the necrotic lesion. MRI is potentially a useful modality for evaluating therapeutic efficacy after RFA to the lung.

  16. Predictors for postoperative esophageal stricture after balloon-based radiofrequency ablation for early esophageal squamous neoplasia: a multicenter validation study

    PubMed Central

    Wang, Wen-Lun; Chang, I-Wei; Chen, Chien-Chuan; Chang, Wei-Lun; Chu, Yin-Yi; Wu, Ping-Hsiu; Tai, Wei-Chen; Chen, Po-Yueh; Hsieh, Ping-Hsin; Chung, Chen-Shuan; Chang, Chi-Yang; Lin, Jaw-Town; Wang, Hsiu-Po; Lee, Ching-Tai

    2016-01-01

    Background: Endoscopic radiofrequency ablation (RFA) is a rapidly evolving therapeutic modality for early flat esophageal squamous cell neoplasms (ESCNs), but the risk factors for postoperative stricture have not been elucidated. The objective of this study was to identify and validate a predictor for post-RFA stenosis. Methods: We consecutively enrolled patients with flat-type ‘large’ (length no less than 3 cm extending no less than half the circumference of the esophagus), early ESCNs, treated with balloon-based RFA (12 J/cm2–clean–12 J/cm2 regimen). The tumor and technical factors for postoperative stricture were investigated and we validated the results externally with a society-based multicenter cohort using the same ablation regimen. Results: A total of 51 patients were enrolled (30 in the development set and 21 in the validation set). The complete remission rate at 12 months was 93%, and the rates of perforation and postoperative stenosis were 0% and 17%, respectively. Patients with post-RFA stenosis had a significantly larger longitudinal tumor size (mean 115 versus 61 mm, p = 0.003). There were no significant differences in age, body mass index, tumor circumferential extension, pretreatment histological grade, treatment efficacy or size of balloon catheter between the groups with or without stenosis. The optimal cut-off value was set as 9 cm to predict post-RFA stenosis by receiver operating characteristic curve [area under curve (AUC) = 0.881], which was then confirmed to be a reliable predictor by multivariate analysis (odds ratio, 12.7, 95% confidence interval, 1.18–136.28, p = 0.03) and have a good predictive performance in the validation set (AUC = 0.876). Conclusions: The most frequent adverse event of RFA was esophageal stenosis, for which the longitudinal tumor size was a significant predictive factor. Early intervention or prevention for stricture should be applied for those with long segment (⩾9 cm) ESCNs. PMID:27134656

  17. Percutaneous radiofrequency ablation for medically inoperable patients with clinical stage I non-small cell lung cancer

    PubMed Central

    Liu, Baodong; Liu, Lei; Hu, Mu; Qian, Kun; Li, Yuanbo

    2015-01-01

    Background A retrospective evaluation of percutaneous radiofrequency ablation (RFA) in medically inoperable patients with clinical stage I non-small cell lung cancer (NSCLC). Methods Between 2008 and 2014, 29 medically inoperable patients with clinical stage I NSCLC underwent percutaneous RFA. We evaluated the feasibility, safety, and effectiveness. Results There were 18 men and 11 women with a median age of 78.0 years (range 56–85), mean 76.0 years. No procedure-related deaths occurred in any of the 33 ablation procedures. The mean follow-up was 25 months. The incidence of local tumor progression was 21.0% at 25 months of median time to progression after the initial RFA. The mean overall survival (OS) was 57 months (95% confidence interval (CI) 44–70 months). The mean cancer-specific survival CSS was 63 months (95% CI 50–75 months). OS was 90.5% ± 6.4% at one year, 76.4% ± 10.7% at two, and 65.5% ± 13.6% at three years. CSS was 95.2% ± 4.6% at one, 86.6% ± 9.3% at two, and 74.2% ± 13.9% at three years in all patients. The survival for stage IA and IB cancers were 87.5% and 92.3% at one, 87.5% and 73.4% at two, and 87.5% and 58.7% at three years, respectively. Survival rates were not significantly different between the two groups (P = 0.596), with mean survival times of 65 (95% CI: 51–79 months) and 55 months (95% CI: 38–71 months), respectively. Conclusion Percutaneous RFA is a safe, feasible, and effective procedure in medically inoperable clinical stage I NSCLC patients. PMID:26273379

  18. Is Antibiotic Prophylaxis for Percutaneous Radiofrequency Ablation (RFA) of Primary Liver Tumors Necessary? Results From a Single-Center Experience

    SciTech Connect

    Bhatia, Shivank S.; Echenique, Ana Froud, Tatiana Suthar, Rekha Lawson, Ivy Dalal, Ravi; Yrizarry, Jose Narayanan, Govindarajan

    2015-08-15

    PurposeThe purpose of this study was to evaluate need for antibiotic prophylaxis for radiofrequency ablation (RFA) of liver tumors in patients with no significant co-existing risk factors for infection.Materials and MethodsFrom January 2004 to September 2013, 83 patients underwent 123 percutaneous RFA procedures for total of 152 hepatocellular carcinoma (HCC) lesions. None of the patients had pre-existing biliary enteric anastomosis (BEA) or any biliary tract abnormality predisposing to ascending biliary infection or uncontrolled diabetes mellitus. No pre- or post-procedure antibiotic prophylaxis was provided for 121 procedures. Data for potential risk factors were reviewed retrospectively and analyzed for the frequency of infectious complications, including abscess formation.ResultsOne patient (1/121 (0.8 %) RFA sessions) developed a large segment 5 liver abscess/infected biloma communicating with the gallbladder 7 weeks after the procedure, successfully treated over 10 weeks with IV and PO antibiotic therapy and percutaneous catheter drainage. This patient did not receive any antibiotics prior to RFA. During the procedure, there was inadvertent placement of RFA probe tines into the gallbladder. No other infectious complications were documented.ConclusionThese data suggest that the routine use of prophylactic antibiotics for liver RFA is not necessary in majority of the patients undergoing liver ablation for HCC and could be limited to patients with high-risk factors such as the presence of BEA or other biliary abnormalities, uncontrolled diabetes mellitus, and large centrally located tumors in close proximity to central bile ducts. Larger randomized studies are needed to confirm this hypothesis.

  19. Combined Therapies for the Treatment of Technically Unresectable Liver Malignancies: Bland Embolization and Radiofrequency Thermal Ablation within the Same Session

    SciTech Connect

    Bonomo, Guido Della Vigna, Paolo Monfardini, Lorenzo Orgera, Gianluigi; Chiappa, Antonio; Bianchi, Paolo Pietro; Zampino, Maria Giulia; Orsi, Franco

    2012-12-15

    Purpose: This retrospective study evaluated the feasibility, efficacy, and safety of combining transcatheter arterial embolization (TAE) with radiofrequency thermal ablation (RFA) in a single session for the treatment of technically unresectable liver-only malignancies. Methods: From May 2006 to January 2011, a total of 30 patients affected by liver metastases with single or multiple unresectable liver-only lesions underwent a combined treatment with TAE followed by RFA in the same session, for a total of 36 treated lesions. Patients were extrapolated from a cohort of patients discussed within the weekly institutional tumor board. TAE was performed by using 100 {mu}m microspheres; RFA was performed immediately after TAE by positioning the electrode needle via ultrasound and/or computed tomographic guidance. Local tumor responses and procedure-related complications were evaluated. Results: Completion of both procedures was obtained in all patients for all 36 lesions. Liver lesions had a maximum axial diameter ranging 16-59 mm. Postintervention unenhanced ablated areas ranged 28-104 mm in maximum axial diameter. Safety margins ranged 1-30.5 mm. Complete response, defined as complete devascularization at computed tomography, was obtained in all treated lesions for a maximum period of 12 months. Tumor relapse was observed in one patient at 12 months. Sixteen patients developed new liver lesions or progressive systemic disease during follow-up. Nine patients were still disease-free. Seven patients died as a result of systemic progressive disease. One major treatment-related complication was observed. Conclusions: In patients with technically unresectable liver-only malignancies, single-session combined TAE-RFA is an effective and safe treatment.

  20. The Efficacy of Radiofrequency Ablation Combined with Transcatheter Arterial Chemoembolization for Primary Hepatocellular Carcinoma in a Cohort of 487 Patients

    PubMed Central

    An, Weimin; Ma, Wei; Qi, Ruping; Yang, Bin; Liu, Chunzi; Gao, Yuanzhi; Xu, Beibei; Wang, Wenhong

    2014-01-01

    Although diagnostic methods, surgical techniques, and perioperative care have undergone significant advancement over the past decades, the prognosis of primary hepatocellular carcinoma (HCC) remains discouraged because of the high postoperative recurrence rate and high cancer mortality. Radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) is a recently developed means for the treatment of HCC. In this study, we analyzed the efficacy of RFA plus TACE in 487 cases of HCC in our institution. We observed that the 1-, 2-, 3-, 4- and 5-year rates of overall survival rates after RFA and TACE treatment were 97.5% (475/487), 89.4% (277/310), 84.2% (181/215), 80.4% (150/186) and 78.7% (141/177), respectively. We did not find that age or tumor location (the caudate group or non-caudate group) plays a role in this cohort. However, we have identified that tumor recurrent status, the number of tumors, albumin (ALB), prothrombin time (PT) and platelet count (PLT) were significantly associated with poor overall survival in HCC patients receiving RFA combined with TACE. Interestingly, tumor size did not significantly impact overall survival, indicating that RFA combined with TACE for HCC treatment has the same efficiency for different sizes of tumors. Our results provide evidence for the rationale for using combined RFA and TACE in the treatment of primary HCC. PMID:24586515

  1. Effectiveness of Computed Tomography Guided Percutaneous Radiofrequency Ablation Therapy for Osteoid Osteoma: Initial Results and Review of the Literature

    PubMed Central

    Karagöz, Erdal; Özel, Deniz; Özkan, Fuat; Özel, Betül Duran; Özer, Özgur; Coşkun, Zafer Ünsal

    2016-01-01

    Summary Background The aim of this retrospective study is to determine our experience of technique success rate, complications and clinical results in long term follow up for computed tomography (CT)-guided radiofrequency ablation [RA] therapy for osteoid osteoma (OO). Material/Methods We performed RA therapy to 18 patients with OO referred to interventional radiology from other clinics primarily from orthopedics; between January 2011 to May 2014. Daytime and nighttime pain intensity of 18 patients was noted according to visual analog scale (VAS). After procedure pain intensity was compared with before one. We also discussed other factors can affect it. Results All procedures were completed technically successful for all patients [100%]. We did not experience any major complication or mortality. However we had 3 minor complications. Pain came back in 1 patient after 5 months from procedure and it was considered as recurrence. Dramatic pain intensity fall was seen in patients after procedure, both daytime and nighttime. However we did not find and statistically significant change in comparison of pain intensity reduce and time needed to return back to routine life when using patients demographic data and lesion size. Conclusions CT guided RA therapy of OO is minimally invasive, effective and secure procedure. PMID:27429671

  2. Radiofrequency Catheter Ablation for Atrial Fibrillation Elicited "Jackhammer Esophagus": A New Complication Due to Vagal Nerve Stimulation?

    PubMed

    Tolone, Salvatore; Savarino, Edoardo; Docimo, Ludovico

    2015-10-01

    Radiofrequency catheter ablation (RFCA) is a potentially curative method for treatment of highly symptomatic and drug-refractory atrial fibrillation (AF). However, this technique can provoke esophageal and nerve lesion, due to thermal injury. To our knowledge, there have been no reported cases of a newly described motor disorder, the Jackhammer esophagus (JE) after RFCA, independently of GERD. We report a case of JE diagnosed by high-resolution manometry (HRM), in whom esophageal symptoms developed 2 weeks after RFCA, in absence of objective evidence of GERD. A 65-year-old male with highly symptomatic, drug-refractory paroxysmal AF was candidate to complete electrical pulmonary vein isolation with RFCA. Prior the procedure, the patient underwent HRM and impedance-pH to rule out GERD or hiatal hernia presence. All HRM parameters, according to Chicago classification, were within normal limits. No significant gastroesophageal reflux was documented at impedance pH monitoring. Patient underwent RFCA with electrical disconnection of pulmonary vein. After two weeks, patient started to complain of dysphagia for solids, with acute chest-pain. The patient repeated HRM and impedance-pH monitoring 8 weeks after RFCA. HRM showed in all liquid swallows the typical spastic hypercontractile contractions consistent with the diagnosis of JE, whereas impedance-pH monitoring resulted again negative for GERD. Esophageal dysmotility can represent a possible complication of RFCA for AF, probably due to a vagal nerve injury, and dysphagia appearance after this procedure must be timely investigated by HRM. PMID:26351090

  3. Radiofrequency ablation coupled with Roux-en-Y gastric bypass: a treatment option for morbidly obese patients with Barrett's esophagus.

    PubMed

    Parikh, Keyur; Khaitan, Leena

    2016-01-01

    Barrett's esophagus (BE) is a premalignant condition that is associated with the development of esophageal adenocarcinoma. Risk factors that have been associated with the development of BE include male gender, Caucasian race, chronic gastroesophageal reflux disease, smoking, age >50 and obesity. The current management of BE is dependent on underlying pathological changes and treatment can range from surveillance endoscopy with daily proton pump inhibitor (PPI) therapy in the setting of intestinal metaplasia or low-grade dysplasia (LGD) to radiofrequency ablation (RFA), endoscopic mucosal resection or surgical resection in the setting of high-grade dysplasia. We report the case of a morbidly obese patient who was found to have long-segment BE with LGD during preoperative work-up for weight loss surgery with Roux-en-Y gastric bypass (RYGBP). The patient underwent successful RFA for the treatment of her BE before and after her RYGBP procedure. At 5-year follow-up, there was minimal progression of BE after treatment. PMID:26945777

  4. Hyaluronic Acid Gel Injection to Prevent Thermal Injury of Adjacent Gastrointestinal Tract during Percutaneous Liver Radiofrequency Ablation

    SciTech Connect

    Hasegawa, Takaaki Takaki, Haruyuki; Miyagi, Hideki; Nakatsuka, Atsuhiro; Uraki, Junji; Yamanaka, Takashi; Fujimori, Masashi; Sakuma, Hajime; Yamakado, Koichiro

    2013-08-01

    This study evaluated the safety, feasibility, and clinical utility of hyaluronic acid gel injection to separate the gastrointestinal tract from the tumor during liver radiofrequency ablation (RFA). Eleven patients with liver tumors measuring 0.9-3.5 cm (mean {+-} standard deviation, 2.1 {+-} 0.8 cm) that were adjacent to the gastrointestinal tracts received RFA after the mixture of hyaluronic acid gel and contrast material (volume, 26.4 {+-} 14.5 mL; range, 10-60 mL) was injected between the tumor and the gastrointestinal tract under computed tomographic-fluoroscopic guidance. Each tumor was separated from the gastrointestinal tract by 1.0-1.5 cm (distance, 1.2 {+-} 0.2 cm) after injection of hyaluronic acid gel, and subsequent RFA was performed without any complications in all patients. Although tumor enhancement disappeared in all patients, local tumor progression was found in a patient (9.1 %, 1 of 11) during the follow-up of 5.5 {+-} 3.2 months (range, 0.4-9.9 months). In conclusion, hyaluronic acid gel injection is a safe and useful technique to avoid thermal injury of the adjacent gastrointestinal tract during liver RFA.

  5. In vivo intracardiac optical coherence tomography imaging through percutaneous access: toward image-guided radio-frequency ablation

    PubMed Central

    Wang, Hui; Kang, Wei; Carrigan, Thomas; Bishop, Austin; Rosenthal, Noah; Arruda, Mauricio; Rollins, Andrew M.

    2011-01-01

    Complete catheter-tissue contact and permanent tissue destruction are essential for efficient radio-frequency ablation (RFA) during cardiac arrhythmia treatment. Current methods of monitoring lesion formation are indirect and unreliable. The purpose of this study is to evaluate the feasibility of using optical coherence tomography (OCT) catheter to image endocardial wall in actively beating hearts through percutaneous access. We reported the first in vivo intracardiac OCT imaging through percutaneous access with a thin and flexible OCT catheter. This is a critical step toward image-guided RFA in a clinical setting. A cone-scanning forward-viewing OCT catheter was advanced into beating hearts through percutaneous access in four swine. The OCT catheter was steered by an introducer to touch the endocardial wall. We are able to acquire high quality OCT images in beating hearts, observe the polarization-related artifacts induced by the birefringence of myocardium, and readily evaluate catheter-tissue contact. The observations indicate that OCT could be a promising technique for in vivo guidance of RFA. PMID:22112101

  6. Prevention and Treatment of Lower Limb Deep Vein Thrombosis after Radiofrequency Catheter Ablation: Results of a Prospective active controlled Study

    PubMed Central

    Li, Lan; Zhang, Bao-jian; Zhang, Bao-ku; Ma, Jun; Liu, Xu-zheng; Jiang, Shu-bin

    2016-01-01

    We conducted a prospective, single-center, active controlled study from July 2013 to January 2015, in Chinese patients with rapid ventricular arrhythmia who had received radiofrequency catheter ablation (RFCA) treatment to determine formation of lower extremity deep vein thrombosis (LDVT) post RFCA procedure, and evaluated the effect of rivaroxaban on LDVT. Patients with asymptomatic pulmonary thromboembolism who had not received any other anticoagulant and had received no more than 36 hours of treatment with unfractionated heparin were included. Post RFCA procedure, patients received either rivaroxaban (10 mg/d for 14 days beginning 2–3 hours post-operation; n = 86) or aspirin (100 mg/d for 3 months beginning 2–3 hours post-operation; n = 90). The primary outcome was a composite of LDVT occurrence, change in diameter of femoral veins, and safety outcomes that were analyzed based on major or minor bleeding events. In addition, blood flow velocity was determined. No complete occlusive thrombus or bleeding events were reported with either of the group. The lower incidence rate of non-occluded thrombus in rivaroxaban (5.8%) compared to the aspirin group (16.7%) indicates rivaroxaban may be administered post-RFCA to prevent and treat femoral venous thrombosis in a secure and effective way with a faster inset of action than standard aspirin therapy. PMID:27329582

  7. Computational Modeling of Open-Irrigated Electrodes for Radiofrequency Cardiac Ablation Including Blood Motion-Saline Flow Interaction.

    PubMed

    González-Suárez, Ana; Berjano, Enrique; Guerra, Jose M; Gerardo-Giorda, Luca

    2016-01-01

    Radiofrequency catheter ablation (RFCA) is a routine treatment for cardiac arrhythmias. During RFCA, the electrode-tissue interface temperature should be kept below 80 °C to avoid thrombus formation. Open-irrigated electrodes facilitate power delivery while keeping low temperatures around the catheter. No computational model of an open-irrigated electrode in endocardial RFCA accounting for both the saline irrigation flow and the blood motion in the cardiac chamber has been proposed yet. We present the first computational model including both effects at once. The model has been validated against existing experimental results. Computational results showed that the surface lesion width and blood temperature are affected by both the electrode design and the irrigation flow rate. Smaller surface lesion widths and blood temperatures are obtained with higher irrigation flow rate, while the lesion depth is not affected by changing the irrigation flow rate. Larger lesions are obtained with increasing power and the electrode-tissue contact. Also, larger lesions are obtained when electrode is placed horizontally. Overall, the computational findings are in close agreement with previous experimental results providing an excellent tool for future catheter research. PMID:26938638

  8. Imaging-Guided Percutaneous Radiofrequency Ablation of Adrenal Metastases: Preliminary Results at a Single Institution with a Single Device

    SciTech Connect

    Carrafiello, G.; Lagana, D.; Recaldini, C.; Giorgianni, A.; Ianniello, A.; Lumia, D.; D'Ambrosio, A.; Petulla, M.; Dionigi, G.; Fugazzola, C.

    2008-07-15

    The aim of this study was to show the feasibility, safety, imaging appearance, and short-term efficacy of image-guided percutaneous radiofrequency ablation (RFA) of adrenal metastases (AM). Seven imaging-guided percutaneous RFA treatments were performed in six patients (two men and four women; mean age, 67.2 years; range, 55-74 years) with six AM who were referred to our institution from 2003 to 2006. One patient was treated twice for recurrence after first treatment. The average diameter of the treated AM was 29 mm (range, 15-40 mm). In all patients, the diagnosis was obtained with CT current protocols in use at our institution and confirmed by pathology with an image-guided biopsy. No major complications occurred. In one patient shortly after initiation of the procedure, severe hypertension was noted; another patient developed post-RFA syndrome. In five of six lesions, there was no residual enhancement of the treated tumor. In one patient CT examination showed areas of residual enhancement of the tumor after treatment. Our preliminary results suggest that imaging-guided percutaneous RFA is effective for local control of AM, without major complications and with a low morbidity rate related to the procedure. Long-term follow-up will need to be performed and appropriate patient selection criteria will need to be determined in future randomized trials.

  9. Radiofrequency Catheter Ablation for Atrial Fibrillation Elicited “Jackhammer Esophagus”: A New Complication Due to Vagal Nerve Stimulation?

    PubMed Central

    Tolone, Salvatore; Savarino, Edoardo; Docimo, Ludovico

    2015-01-01

    Radiofrequency catheter ablation (RFCA) is a potentially curative method for treatment of highly symptomatic and drug-refractory atrial fibrillation (AF). However, this technique can provoke esophageal and nerve lesion, due to thermal injury. To our knowledge, there have been no reported cases of a newly described motor disorder, the Jackhammer esophagus (JE) after RFCA, independently of GERD. We report a case of JE diagnosed by high-resolution manometry (HRM), in whom esophageal symptoms developed 2 weeks after RFCA, in absence of objective evidence of GERD. A 65-year-old male with highly symptomatic, drug-refractory paroxysmal AF was candidate to complete electrical pulmonary vein isolation with RFCA. Prior the procedure, the patient underwent HRM and impedance-pH to rule out GERD or hiatal hernia presence. All HRM parameters, according to Chicago classification, were within normal limits. No significant gastroesophageal reflux was documented at impedance pH monitoring. Patient underwent RFCA with electrical disconnection of pulmonary vein. After two weeks, patient started to complain of dysphagia for solids, with acute chest-pain. The patient repeated HRM and impedance-pH monitoring 8 weeks after RFCA. HRM showed in all liquid swallows the typical spastic hypercontractile contractions consistent with the diagnosis of JE, whereas impedance-pH monitoring resulted again negative for GERD. Esophageal dysmotility can represent a possible complication of RFCA for AF, probably due to a vagal nerve injury, and dysphagia appearance after this procedure must be timely investigated by HRM. PMID:26351090

  10. Impact of radiofrequency ablation for patients with varicose veins on the budget of the German statutory health insurance system

    PubMed Central

    2013-01-01

    Objectives In contrast to other countries, surgery still represents the common invasive treatment for varicose veins in Germany. However, radiofrequency ablation, e.g. ClosureFast, becomes more and more popular in other countries due to potential better results and reduced side effects. This treatment option may cause less follow-up costs and is a more convenient procedure for patients, which could justify an introduction in the statutory benefits catalogue. Therefore, we aim at calculating the budget impact of a general reimbursement of ClosureFast in Germany. Methods To assess the budget impact of including ClosureFast in the German statutory benefits catalogue, we developed a multi-cohort Markov model and compared the costs of a “World with ClosureFast” with a “World without ClosureFast” over a time horizon of five years. To address the uncertainty of input parameters, we conducted three different types of sensitivity analysis (one-way, scenario, probabilistic). Results In the Base Case scenario, the introduction of the ClosureFast system for the treatment of varicose veins saves costs of about 19.1 Mio. € over a time horizon of five years in Germany. However, the results scatter in the sensitivity analyses due to limited evidence of some key input parameters. Conclusions Results of the budget impact analysis indicate that a general reimbursement of ClosureFast has the potential to be cost-saving in the German Statutory Health Insurance. PMID:23551943

  11. A study on the measurement of the core body temperature change after radiofrequency ablation (RFA) through MR temperature mapping

    NASA Astrophysics Data System (ADS)

    Kim, Chang-Bok; Dong, Kyung-Rae; Yu, Young; Chung, Woon-Kwan; Cho, Jae-Hwan; Joo, Kyu-Ji

    2013-09-01

    This study examined the change in the heat generated during radiofrequency ablation (RFA) using a self-manufactured phantom and used magnetic resonance imaging (MRI) to analyze the change in the temperature of the core body and the tissues surrounding the phantom. In this experiment, the image and the phase image were obtained simultaneously from a gradient echo-based sequence using 1.5-Tesla MRI equipment and a 12-channel head coil. The temperature mapping technique was used to calculate the change in temperature. The regions of interest (ROIs) (ROI 1 - ROI 6) were set with a focus on the area where the RFA was performed, according to the temperature distribution, before monitoring the temperature change for one hour in time intervals of five minutes. The results showed that the temperature change in the ROI with time was largest in the ROI 1 and smallest in the ROI 5. In addition, after the RFA procedure, the temperature decreased from the initial value to 0 °C in one hour. The temperature changes in the core body and the surrounding tissues were confirmed by MRI temperature mapping, which is a noninvasive method.

  12. Radiofrequency ablation coupled with Roux-en-Y gastric bypass: a treatment option for morbidly obese patients with Barrett's esophagus

    PubMed Central

    Parikh, Keyur; Khaitan, Leena

    2016-01-01

    Barrett's esophagus (BE) is a premalignant condition that is associated with the development of esophageal adenocarcinoma. Risk factors that have been associated with the development of BE include male gender, Caucasian race, chronic gastroesophageal reflux disease, smoking, age >50 and obesity. The current management of BE is dependent on underlying pathological changes and treatment can range from surveillance endoscopy with daily proton pump inhibitor (PPI) therapy in the setting of intestinal metaplasia or low-grade dysplasia (LGD) to radiofrequency ablation (RFA), endoscopic mucosal resection or surgical resection in the setting of high-grade dysplasia. We report the case of a morbidly obese patient who was found to have long-segment BE with LGD during preoperative work-up for weight loss surgery with Roux-en-Y gastric bypass (RYGBP). The patient underwent successful RFA for the treatment of her BE before and after her RYGBP procedure. At 5-year follow-up, there was minimal progression of BE after treatment. PMID:26945777

  13. Comparative analysis of intraoperative radiofrequency ablation versus non-anatomical hepatic resection for small hepatocellular carcinoma: short-term result

    PubMed Central

    Yune, Yongwoo; Kim, Seokwhan; Song, Insang

    2015-01-01

    Backgrounds/Aims To compare the clinical outcomes of intraoperative radiofrequency ablation (RFA) and non-anatomical hepatic resection (NAHR) for small hepatocellular carcinoma (HCC). Methods From February 2007 to January 2015, clinical outcomes of thirty four patients with HCC receiving RFA or NAHR were compared, retrospectively. Results There was no difference of patient and tumor characteristic between the two groups that received RFA or NAHR. The 1, 2, and 3-year recurrence rates following RFA were 32.2%, 32.2% and 59.3% respectively, and 6.7%, 33.3% and 33.3% following NAHR respectively (p=0.287). The 1, 2 and 3-year overall survival (OS) rates following RFA were 100%, 88.9% and 76.2% respectively, and 100%, 85.6% and 85.6%, respectively, following NAHR (p=0.869). We did not find a definite statistical difference in recurrence rate and OS rate between the two groups. In the multivariate analysis, number of tumor was an independent prognostic factor for recurrence and albumin was an independent prognostic factor for OS. Conclusions We recommend non-anatomical hepatic resection rather than intraoperative RFA in small sized HCC, due to a higher recurrence rate in intraoperative RFA. Intraoperative RFA was inferior to non-anatomical hepatic resection in terms of recurrence rate. We need to select the optimal treatment considering liver function and possibility of recurrence. PMID:26693237

  14. Computational Modeling of Open-Irrigated Electrodes for Radiofrequency Cardiac Ablation Including Blood Motion-Saline Flow Interaction

    PubMed Central

    González-Suárez, Ana; Berjano, Enrique; Guerra, Jose M.; Gerardo-Giorda, Luca

    2016-01-01

    Radiofrequency catheter ablation (RFCA) is a routine treatment for cardiac arrhythmias. During RFCA, the electrode-tissue interface temperature should be kept below 80°C to avoid thrombus formation. Open-irrigated electrodes facilitate power delivery while keeping low temperatures around the catheter. No computational model of an open-irrigated electrode in endocardial RFCA accounting for both the saline irrigation flow and the blood motion in the cardiac chamber has been proposed yet. We present the first computational model including both effects at once. The model has been validated against existing experimental results. Computational results showed that the surface lesion width and blood temperature are affected by both the electrode design and the irrigation flow rate. Smaller surface lesion widths and blood temperatures are obtained with higher irrigation flow rate, while the lesion depth is not affected by changing the irrigation flow rate. Larger lesions are obtained with increasing power and the electrode-tissue contact. Also, larger lesions are obtained when electrode is placed horizontally. Overall, the computational findings are in close agreement with previous experimental results providing an excellent tool for future catheter research. PMID:26938638

  15. In vivo intracardiac optical coherence tomography imaging through percutaneous access: toward image-guided radio-frequency ablation

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Kang, Wei; Carrigan, Thomas; Bishop, Austin; Rosenthal, Noah; Arruda, Mauricio; Rollins, Andrew M.

    2011-11-01

    Complete catheter-tissue contact and permanent tissue destruction are essential for efficient radio-frequency ablation (RFA) during cardiac arrhythmia treatment. Current methods of monitoring lesion formation are indirect and unreliable. The purpose of this study is to evaluate the feasibility of using optical coherence tomography (OCT) catheter to image endocardial wall in actively beating hearts through percutaneous access. We reported the first in vivo intracardiac OCT imaging through percutaneous access with a thin and flexible OCT catheter. This is a critical step toward image-guided RFA in a clinical setting. A cone-scanning forward-viewing OCT catheter was advanced into beating hearts through percutaneous access in four swine. The OCT catheter was steered by an introducer to touch the endocardial wall. We are able to acquire high quality OCT images in beating hearts, observe the polarization-related artifacts induced by the birefringence of myocardium, and readily evaluate catheter-tissue contact. The observations indicate that OCT could be a promising technique for in vivo guidance of RFA.

  16. Incidence and Factors Predicting Skin Burns at the Site of Indifferent Electrode during Radiofrequency Catheter Ablation of Cardiac Arrhythmias

    PubMed Central

    Ibrahim, Hussain; Finta, Bohuslav; Rind, Jubran

    2016-01-01

    Radiofrequency catheter ablation (RFA) has become a mainstay for treatment of cardiac arrhythmias. Skin burns at the site of an indifferent electrode patch have been a rare, serious, and likely an underreported complication of RFA. The purpose of this study was to determine the incidence of skin burns in cardiac RFA procedures performed at one institution. Also, we wanted to determine the factors predicting skin burns after cardiac RFA procedures at the indifferent electrode skin pad site. Methods. A retrospective case control study was performed to compare the characteristics in patients who developed skin burns in a 2-year period. Results. Incidence of significant skin burns after RFA was 0.28% (6/2167). Four of the six patients were female and all were Caucasians. Four controls for every case were age and sex matched. Burn patients had significantly higher BMI, procedure time, and postprocedure pain, relative to control subjects (p < 0.05, one-tailed testing). No one in either group had evidence of dispersive pad malattachment. Conclusions. Our results indicate that burn patients had higher BMI and longer procedure times compared to control subjects. These findings warrant further larger studies on this topic. PMID:27213077