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Sample records for bipolar radiofrequency ablation

  1. Bipolar radiofrequency ablation of tibialchondroblastomas: A report of three cases.

    PubMed

    Rajalakshmi, Prathiba; Srivastava, Deep N; Rastogi, Shishir; Julka, Pramod Kumar; Bhatnagar, Sushma; Gamanagatti, Shivanand

    2012-07-28

    Chondroblastoma is a rare benign cartilaginous neoplasm of bone. The recurrence rate is high and complications are frequent following open curettage with bone grafting which is the standard treatment forchondroblastomas. We performed radiofrequency ablation in three cases of tibialchondroblastoma using the bipolar system. One patient experienced residual pain for which repeat ablation was performed. No other complications were observed during follow-up. Radiofrequency ablation may offer an effective alternative for the treatment of selected cases of chondroblastoma. The lesion characteristics which are likely to influence treatment outcome and the advantages offered by the bipolar system are discussed. PMID:22900136

  2. 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.

  3. 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.

  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.

  5. A left atrial ablation with bipolar irrigated radio-frequency for atrial fibrillation during minimally invasive mitral valve surgery.

    PubMed

    Solinas, Marco; Bevilacqua, Stefano; Karimov, Jamshid H; Glauber, Mattia

    2010-04-01

    Minimally invasive mitral valve surgery is becoming increasingly popular worldwide. Mitral valve disease is often associated with atrial fibrillation (AF), also due to the ageing of the population. We present a technique to perform a left atrial ablation with bipolar irrigated radio-frequency (RF) through a single right thoracotomy. We have operated on eight patients: six female with a mean age 68+/-8 years. Six patients suffered from permanent AF and other two from paroxysmal AF. PMID:19942447

  6. Effect of novel modified bipolar radiofrequency ablation for preoperative atrial fibrillation combined with off-pump coronary artery bypass grafting surgery.

    PubMed

    Jiang, Zhaolei; Ma, Nan; Tang, Min; Liu, Hao; Ding, Fangbao; Yin, Hang; Mei, Ju

    2015-11-01

    We described a novel modified bipolar radiofrequency (RF) ablation for preoperative atrial fibrillation (AF) combined with off-pump coronary artery bypass grafting (OPCABG) for patients with AF and coronary artery disease (CAD). The aim of this study was to assess the effect of this novel procedure and to determine whether it can eliminate AF for CAD patients. From January 2007 to June 2013, 45 patients (26 male patients) with AF (9 paroxysmal, 17 persistent, and 19 long-standing persistent) and CAD underwent the novel modified bipolar RF ablation combined with OPCABG in our department. After median sternotomy, the modified bipolar RF ablation and OPCABG were performed on beating heart without cardiopulmonary bypass. Pulmonary vein isolation and left atrium ablation were achieved using a bipolar RF champ. Mitral annular lesion and ganglionic plexus were ablated with a bipolar RF pen. The left atrial appendage was excluded using a surgical stapler. 24 h holter monitoring and echocardiography were performed at discharge and 3, 6, 12 months postoperatively as well as every year thereafter. The modified bipolar RF ablation and OPCABG were performed successfully in all patients. Mean AF ablation time was 33.6 ± 4.2 min, and mean OPCABG time was 87.6 ± 13.3 min. Mean postoperative hospital stay was 12.6 ± 5.5 days. The maintenance of sinus rhythm was 95.6 % (43/45) at discharge. There was no early death and permanent pacemaker implantation in perioperation. At a mean follow-up of 29.8 ± 10.2 months, 38 of 45 (84.4 %) patients were in sinus rhythm. Follow-up TTE at 6 months postoperatively showed that left atrial diameter was significantly reduced and left ventricular ejection fraction was significantly increased. The novel modified bipolar RF ablation procedure was safe, feasible and effective. It may be useful in selecting the best ablation approaches for patients with AF and CAD. PMID:24820449

  7. 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.

  8. 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

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

    PubMed

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

    2016-01-01

    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.

  10. Ex Vivo Experiment of Saline-Enhanced Hepatic Bipolar Radiofrequency Ablation with a Perfused Needle Electrode: Comparison with Conventional Monopolar and Simultaneous Monopolar Modes

    SciTech Connect

    Lee, Jeong Min Kim, Se Hyung; Han, Joon Koo; Sohn, Kyu Li; Choi, Byung Ihn

    2005-04-15

    The purpose of this study was to validate the saline-enhanced bipolar radiofrequency ablation (RFA) technique using a perfused electrode to increase RF-created coagulation necrosis, to compare that technique with monopolar RFAs and to find appropriate concentrations and volumes of perfused NaCl solution for the bipolar RFA. A total of 90 ablations were performed in explanted bovine livers. In the initial experiments to determine appropriate conditions for bipolar RFA, we created five thermal ablation zones in each condition, with instillations of varied concentrations (0.9-36%) or injection rates (30 mL/hr-120 mL/hr) of NaCl solution. After placement of one or two 16-gauge open-perfused electrodes into bovine livers, the NaCl solution was instilled into the tissue through the electrode. In the second part of the study, 10 ablation zones were created using one or two perfused electrodes for each of five groups under different conditions: a conventional monopolar mode with 0.9% NaCl solution (group A) or with 6% NaCl solution (group B), a simultaneous monopolar mode with 6% NaCl solution (group C) and a bipolar mode with 6% NaCl solution (groups D and E). RF was applied to each electrode for 20 min in groups A, B, C, and E, or for 10 min in group D. During RFA, we measured the tissue temperature 15 mm from the electrode. The temperature changes during the RFA and the dimensions of the ablation zones were compared among the groups. Bipolar RFA created larger short-axis diameters of coagulation necrosis with 6% NaCl solution (35.8 {+-} 15 mm) than with 0.9% NaCl solution (17 {+-} 9.7 mm) (P < 0.05). However, concentrations of NaCl solution above 6% did not further increase the extent of coagulation necrosis. In addition, bipolar RFA with 6% NaCl solution instillation at a rate of 1.0 mL/min (37.9 {+-} 5.4 mm) or 2.0 mL/min (35.6 {+-} 9.3 mm) produced larger diameters at the mid-point between the electrodes of the ablated lesion than did 0.5 mL/min (25.8 {+-} 9.3 mm) (P

  11. 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

  12. 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

  13. Radiofrequency ablation of lung tumours

    PubMed Central

    Goh, PYT

    2006-01-01

    Radiofrequency ablation (RFA) is a well-established local therapy for hepatic malignancies. It is rapidly emerging as an effective treatment modality for small lesions elsewhere in the body, in particular, the kidney and the lung. It is a relatively safe and minimally invasive treatment for small lung malignancies, both primary and secondary. In particular, it is the preferred form of treatment for non-surgical candidates. This paper describes the technique employed for radiofrequency ablation of lung tumours, as well as the protocol established, at the Mount Elizabeth Hospital, Singapore. PMID:21614247

  14. 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

  15. 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 ...

  16. Radiofrequency Ablation Beyond the Liver

    PubMed Central

    Neeman, Ziv; Wood, Bradford J.

    2008-01-01

    Radiofrequency ablation (RFA) has begun to show promise for extrahepatic indications. Although much of the reported work on image-guided RFA of liver neoplasms is quite promising, it is even earlier in the evaluation and validation process for extrahepatic RFA, with few short-term and no long-term studies reported. Although there are much more data for liver RFA with almost 3,000 cases reported in the literature, there are a number of ongoing investigations of RFA for tumors in the kidney, lung, bone, breast, bone, and adrenal gland. Debulking and pain control with RFA present palliative options becoming increasingly popular weapons in the interventionalist's oncology arsenal. Metastatic disease with a wide variety of primary histologies in a myriad of locations may be treated with RFA after a careful consideration of the risk-to-benefit ratio balance. The RFA technique can be slightly different outside the liver. Specifically, differing dielectric tissue characteristics may markedly alter the RFA treatment. Each different RFA system has a unique risk and advantage profile. Extrahepatic indications and contraindications will be suggested. Treatment tips and the unique complications and considerations will be introduced for some of the more common extrahepatic locations. PMID:12524646

  17. 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 ...

  18. 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.

  19. [Radiofrequency transcatheter ablation in atrial tachycardia].

    PubMed

    Velázquez Rodríguez, E; Morales Hernández, J A

    2000-01-01

    Incessant atrial tachycardia is an infrequent arrhythmia. Specially difficult to treat medically. Radiofrequency catheter ablation has been used successfully to cure a variety of supraventricular tachycardias. The purpose of this work is to report our initial experience in the treatment of atrial tachycardia. Ten patients, mean age 28.7 +/- 15 year with conventional drug-resistant symptomatic atrial tachycardia were treated with selective ablation of the focus using radiofrequency energy. It was found an abnormal automaticity in 10 tachycardias and in only one patient intra-atrial reentrant was supported. Radiofrequency energy was successful in 10 of 11 tachycardias with a mean of 9.3 +/- 6.8 applications using the technique of local atrial electrogram activation time with a mean value of -54 +/- -31 milliseconds at the successful ablation sites. No complications were observed and one patient had an early clinical recurrence. All patients with successful ablation are symptom-free, in sinus rhythm and without antiarrhythmic medications after 1 to 28 months of follow-up. Our initial experience support that radiofrequency catheter ablation is a safe and effective therapeutic option for incessant atrial tachycardia. PMID:10855411

  20. 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

  1. [Radiofrequency ablation of an unresectable abdominal tumor].

    PubMed

    Sézeur, Alain; Fritsch, Sylvie; Louvet, Christophe; Kujas, Albert; Mosnier, Henri; Talbot, Jean-Noël; Grimberg, Sylvie

    2003-02-01

    Remnant malignant tissue is left behind after conventional surgery for an unresectable intraperitoneal malignant tumor. Standard radiotherapy or chemotherapy rarely enables good tumor control. We report the case of a 74-year-old man who developed a local recurrence of a sigmoid tumor located 5 to 6 cm from the anus. The tumor was fixed to the pelvic wall and could not be totally eradicated with conventional surgery. Preoperative peroperative assessment confirmed the absence of metastatic spread. Radiotherapy could not be performed due to risk of bowel injury. Peroperative radiofrequency ablation was followed by surgical colorectal resection without restoration of intestinal continuity, leaving only tumor tissue destroyed by radiofrequency. No adjuvant treatment was proposed because of intolerance to chemotherapy. Clinical assessment and thoracic and abdominal CT scan confirmed the absence of recurrence 26 months after radiofrequency ablation. Serum markers remained normal.

  2. Characterization of tracked radiofrequency ablation in phantom

    SciTech Connect

    Chen, Chun-Cheng R.; Miga, Michael I.; Galloway, Robert L.

    2007-10-15

    In radiofrequency ablation (RFA), successful therapy requires accurate, image-guided placement of the ablation device in a location selected by a predictive treatment plan. Current planning methods rely on geometric models of ablations that are not sensitive to underlying physical processes in RFA. Implementing plans based on computational models of RFA with image-guided techniques, however, has not been well characterized. To study the use of computational models of RFA in planning needle placement, this work compared ablations performed with an optically tracked RFA device with corresponding models of the ablations. The calibration of the tracked device allowed the positions of distal features of the device, particularly the tips of the needle electrodes, to be determined to within 1.4{+-}0.6 mm of uncertainty. Ablations were then performed using the tracked device in a phantom system based on an agarose-albumin mixture. Images of the sliced phantom obtained from the ablation experiments were then compared with the predictions of a bioheat transfer model of RFA, which used the positional data of the tracked device obtained during ablation. The model was demonstrated to predict 90% of imaged pixels classified as being ablated. The discrepancies between model predictions and observations were analyzed and attributed to needle tracking inaccuracy as well as to uncertainties in model parameters. The results suggest the feasibility of using finite element modeling to plan ablations with predictable outcomes when implemented using tracked RFA.

  3. 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

  4. Pulmonary radiofrequency ablation (Part 1): current state.

    PubMed

    Plasencia Martínez, J M

    2015-01-01

    The risks involved in surgical treatment and conventional radiotherapy in patients with early lung cancer or lung metastases often make these treatments difficult to justify. However, on the other hand, it is also unacceptable to allow these lesions to evolve freely because, left untreated, these neoplasms will usually lead to the death of the patient. In recent years, alternative local therapies have been developed, such as pulmonary radiofrequency ablation, which has proven to increase survival with a minimal risk of complications. There are common recommendations for these treatments, and although the specific indications for using one technique or another have yet to be established, there are clearly defined situations that will determine the outcome of the treatment. It is important to know these situations, because appropriate patient selection is essential for therapeutic success. This article aims to describe the characteristics and constraints of pulmonary radiofrequency ablation and to outline its role in thoracic oncology in light of the current evidence. PMID:25766072

  5. Pulmonary radiofrequency ablation (Part 1): current state.

    PubMed

    Plasencia Martínez, J M

    2015-01-01

    The risks involved in surgical treatment and conventional radiotherapy in patients with early lung cancer or lung metastases often make these treatments difficult to justify. However, on the other hand, it is also unacceptable to allow these lesions to evolve freely because, left untreated, these neoplasms will usually lead to the death of the patient. In recent years, alternative local therapies have been developed, such as pulmonary radiofrequency ablation, which has proven to increase survival with a minimal risk of complications. There are common recommendations for these treatments, and although the specific indications for using one technique or another have yet to be established, there are clearly defined situations that will determine the outcome of the treatment. It is important to know these situations, because appropriate patient selection is essential for therapeutic success. This article aims to describe the characteristics and constraints of pulmonary radiofrequency ablation and to outline its role in thoracic oncology in light of the current evidence.

  6. Pulmonary Vein Stenosis Complicating Radiofrequency Catheter Ablation

    PubMed Central

    Lu, Hai-Wen; Wei, Ping; Jiang, Sen; Gu, Shu-yi; Fan, Li-Chao; liang, Shuo; Ji, Xiaobin; Rajbanshi, Bhavana; Xu, Jin-Fu

    2015-01-01

    Abstract The aim of this study is to characterize the clinical manifestations and features of pulmonary vein stenosis (PVS) by retrospectively analyzing clinical data of patients in addition to reviewing the literature simultaneously to improve the understanding of PVS complicating radiofrequency catheter ablation and to provide evidence for early diagnosis and timely treatment. Clinical, imaging, and follow-up data of 5 patients with PVS-complicating radiofrequency catheter ablation were retrospectively analyzed between January 2012 and December 2014 in Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China. Relevant studies previously reported were also reviewed. Three out of 5 patients received pulmonary angiography. The initial symptoms were not specific, presenting chest pain in 3 cases, hemoptysis in 2 cases. The average duration between radiofrequency ablation to the onset of symptoms was 5.8 months. The chest image results were consolidation and pleural effusion mainly. Veins distributed in the left lungs were mostly influenced in 4 patients, and the inferior veins in 3 patients. Cardiac ultrasound examinations showed pulmonary arterial hypertension in 2 patients. Two patients received selective bronchial artery embolization after bronchial artery radiography because of hemoptysis. One patient underwent video-assisted thoracoscopic biopsy because of the suspicion of tumor. PVS is a condition mostly undetected because of its silent manifestations and inconsistent follow-up. The accurate clinical diagnosis is very difficult. A careful review of medical history and follow-up observation may be useful for all the patients who received the radiofrequency catheter ablation to recognize PVS in the early stage. PMID:26313772

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. 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.

  15. Radiofrequency interstitial tumor ablation: dry electrode.

    PubMed

    Johnson, D Brooke; Cadeddu, Jeffrey A

    2003-10-01

    With the shift in the treatment of small renal tumors from radical extirpative surgery to nephron-sparing approaches, dry-electrode radiofrequency ablation (RFA) has emerged as one potential modality. This application of RF energy leads to the production of heat within the treatment zone secondary to the native impedance of living tissue. Animal studies and human clinical series have demonstrated that RFA can create controlled, targeted, reproducible, and lethal lesions. Most clinical series have reported promising results, although some authors question the totality of tumor destruction by RFA. With time, the efficacy of RFA, as measured by patient survival, will be determined. Once this is known, RFA may be compared with other therapeutic modalities for small renal tumors to determine its place.

  16. Radiofrequency ablation of a misdiagnosed Brodie's abscess.

    PubMed

    Chan, Rs; Abdullah, Bjj; Aik, S; Tok, Ch

    2011-04-01

    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.

  17. 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

  18. 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.

  19. 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

  20. Radiofrequency Ablation of Renal Tumors: Our Experience

    PubMed Central

    Kim, Jeong Ho; Kim, Tae Hyo; Kim, Soo Dong; Lee, Ki Soo

    2011-01-01

    Purpose To report our results of nephron-sparing radiofrequency ablation (RFA) of renal tumors. Materials and Methods Since August 2004, 49 patients with renal tumors were treated with either percutaneous or laparoscopic RFA. All patients underwent preoperative imaging with contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) and were suspected to have renal cell carcinoma. The follow-up for each patient included a physical examination, chest radiography, liver function tests, and a contrast-enhanced CT or MRI. To confirm the pathologic criteria of complete ablation, 30 patients underwent 6-month or 1-year follow-up biopsy. Recurrence was defined as growth of the tumor or any new enhancing portions at 3 months after confirmed nonenhancement of the initial RFA lesion. Results Technical success was achieved in 46/49 cases (94%). The mean tumor size was 2.4 cm and the mean follow-up period was 31.7 months (range, 6-68 months). Of 49 patients, repeated RFA was necessary in 7 patients (14%). Three patients were found to have recurrence at various follow-up intervals. Twenty-three patients (47%) experienced complications, and all but one necessitated intervention. No distant metastasis was found in any cases, and all patients are alive and are being serially followed up. Conclusions Percutaneous or laparoscopic RFA is considered to be a useful treatment for selected patients with small renal masses and for nephron-sparing. With a mean follow-up of 31.7 months, our intermediate data suggest excellent therapeutic outcome with RFA with effective local tumor control and preservation of renal function. The ultimate role of this modality will continue to evolve and warrants further studies. PMID:21927699

  1. A Rare Complication of Radiofrequency Tonsil Ablation: Horner Syndrome

    PubMed Central

    Ozbay, Isa; Yildirim, Nadir; Zeybek Sivas, Zuhal; Canbaz Kabay, Sibel

    2015-01-01

    Chronic tonsillitis is a common disease, and several different surgical techniques are used to treat this condition. In recent years, techniques such as radiofrequency ablation and coblation have been commonly used for tonsil surgery. In this report, we present the cases of two pediatric patients who developed ptosis, miosis, and enophthalmos (Horner syndrome) after radiofrequency ablation for tonsil reduction and discuss the technique of radiofrequency ablation of the tonsils. In the early postoperative period, miosis and ptosis were observed on the right side in one patient and on the left side in the other patient. Both patients were treated with 1 mg/kg/day methylprednisolone, which were tapered by halving the dose every 3 days. Miosis and ptosis improved after treatment in both patients. Along with the case presentation, we discuss the effectiveness and complications of radiofrequency ablation of the tonsils. These unusual complications of tonsil ablation may help ENT physicians who do not yet have a preferred surgical technique for tonsillectomy to make an informed decision. Limited data are available about the possible complications of radiofrequency ablation of the tonsils. The present report contributes to the literature on this topic. PMID:26064747

  2. A Rare Complication of Radiofrequency Tonsil Ablation: Horner Syndrome.

    PubMed

    Kucur, Cuneyt; Ozbay, Isa; Oghan, Fatih; Yildirim, Nadir; Zeybek Sivas, Zuhal; Canbaz Kabay, Sibel

    2015-01-01

    Chronic tonsillitis is a common disease, and several different surgical techniques are used to treat this condition. In recent years, techniques such as radiofrequency ablation and coblation have been commonly used for tonsil surgery. In this report, we present the cases of two pediatric patients who developed ptosis, miosis, and enophthalmos (Horner syndrome) after radiofrequency ablation for tonsil reduction and discuss the technique of radiofrequency ablation of the tonsils. In the early postoperative period, miosis and ptosis were observed on the right side in one patient and on the left side in the other patient. Both patients were treated with 1 mg/kg/day methylprednisolone, which were tapered by halving the dose every 3 days. Miosis and ptosis improved after treatment in both patients. Along with the case presentation, we discuss the effectiveness and complications of radiofrequency ablation of the tonsils. These unusual complications of tonsil ablation may help ENT physicians who do not yet have a preferred surgical technique for tonsillectomy to make an informed decision. Limited data are available about the possible complications of radiofrequency ablation of the tonsils. The present report contributes to the literature on this topic.

  3. A Rare Complication of Radiofrequency Tonsil Ablation: Horner Syndrome.

    PubMed

    Kucur, Cuneyt; Ozbay, Isa; Oghan, Fatih; Yildirim, Nadir; Zeybek Sivas, Zuhal; Canbaz Kabay, Sibel

    2015-01-01

    Chronic tonsillitis is a common disease, and several different surgical techniques are used to treat this condition. In recent years, techniques such as radiofrequency ablation and coblation have been commonly used for tonsil surgery. In this report, we present the cases of two pediatric patients who developed ptosis, miosis, and enophthalmos (Horner syndrome) after radiofrequency ablation for tonsil reduction and discuss the technique of radiofrequency ablation of the tonsils. In the early postoperative period, miosis and ptosis were observed on the right side in one patient and on the left side in the other patient. Both patients were treated with 1 mg/kg/day methylprednisolone, which were tapered by halving the dose every 3 days. Miosis and ptosis improved after treatment in both patients. Along with the case presentation, we discuss the effectiveness and complications of radiofrequency ablation of the tonsils. These unusual complications of tonsil ablation may help ENT physicians who do not yet have a preferred surgical technique for tonsillectomy to make an informed decision. Limited data are available about the possible complications of radiofrequency ablation of the tonsils. The present report contributes to the literature on this topic. PMID:26064747

  4. 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.

  5. Radiofrequency ablation of hepatic tumors: lessons learned from 3000 procedures.

    PubMed

    Rhim, Hyunchul; Lim, Hyo K; Kim, Young-sum; Choi, Dongil; Lee, Won Jae

    2008-10-01

    Radiofrequency ablation has been accepted as the most popular local ablative therapy for unresectable malignant hepatic tumors. For 9 years from April 1999, we performed 3000 radiofrequency ablation procedures for hepatic tumors in our institution. Our results on the safety (mortality, 0.15%/patient) and therapeutic efficacy (5-year survival rate, 58%) are similar to those of previous studies reported, supporting the growing evidence of a clear survival benefit, excellent results for local tumor control and improved quality of life. The most important lesson learned from our 3000 procedures is that the best planning, safe ablation and complete ablation are key factors for patient outcome. Furthermore, multimodality treatment is the best strategy for recurrent hepatocellular carcinoma encountered after any kind of first-line treatment.

  6. 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

  7. Thermal Protection with 5% Dextrose Solution Blanket During Radiofrequency Ablation

    SciTech Connect

    Chen, Enn Alexandria Neeman, Ziv; Lee, Fred T.; Kam, Anthony; Wood, Brad

    2006-12-15

    A serious complication for any thermal radiofrequency ablation is thermal injury to adjacent structures, particularly the bowel, which can result in additional major surgery or death. Several methods using air, gas, fluid, or thermometry to protect adjacent structures from thermal injury have been reported. In the cases presented in this report, 5% dextrose water (D5W) was instilled to prevent injury to the bowel and diaphragm during radiofrequency ablation. Creating an Insulating envelope or moving organs with D5W might reduce risk for complications such as bowel perforation.

  8. Endovenous radiofrequency ablation for the treatment of varicose veins.

    PubMed

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

    2015-04-01

    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.

  9. 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.

  10. [Infectious mitral endocarditis after radiofrequency catheter ablation of a left lateral accessory pathway].

    PubMed

    Benito Bartolomé, F; Sánchez Fernández-Bernal, C

    2001-08-01

    A 2-years-old child with Wolff-Parkinson-White syndrome associated with life-threatening symptoms underwent radiofrequency ablation of a left lateral accessory pathway. A deflectable 5F bipolar electrode catheter positioned above the atrioventricular groove by transeptal approach was used for ablation. The catheters were repeatedly used after ethylene oxide sterilisation. Although immediate post-ablation echocardiography demonstrated no complications, the patient was readmitted two days later with fever and a new mitral murmur. Penicillin-susceptible Staphylococcus aureus was isolated and intravenous antibiotics were administered. In the following weeks, the patient developed constrictive pericarditis requiring surgical treatment and acute hemiplegia caused by brain embolism arising from valvular vegetation. At 5 years of follow-up the patient presents residual hemiparesia and grade II/IV mitral insufficiency. PMID:11481116

  11. 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

  12. Palliation of Painful Perineal Metastasis Treated with Radiofrequency Thermal Ablation

    SciTech Connect

    Thanos, L. Mylona, S.; Kalioras, V.; Pomoni, M.; Batakis, N.

    2005-04-15

    We report a case of painful perineal metastasis from urinary bladder carcinoma in a 73-years-old woman, treated with CT-guided radiofrequency ablation (RFA). The pain was immediately relieved and follow-up at 1 and 6 months showed total necrosis of the mass. One year later, the patient has no pain and her quality of life is improved.

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. Endometrial ablation

    MedlinePlus

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

  18. Intraductal radiofrequency ablation for management of malignant biliary obstruction.

    PubMed

    Rustagi, Tarun; Jamidar, Priya A

    2014-11-01

    Self-expandable metal stents (SEMS) are the current standard of care for the palliative management of malignant biliary strictures. Recently, endoscopic ablative techniques with direct affect to local tumor have been developed to improve SEMS patency. Several reports have demonstrated the technical feasibility and safety of intraductal radiofrequency ablation (RFA), by both endoscopic and percutaneous approaches, in palliation of malignant strictures of the bile duct. Intraductal RFA has also been used in the treatment of occlusion of both covered and uncovered SEMS occlusion from tumor ingrowth or overgrowth. This article provides a comprehensive review of intraductal RFA in the management of malignant biliary obstruction.

  19. 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.

  20. 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.

  1. Architecture of the pulmonary veins: relevance to radiofrequency ablation

    PubMed Central

    Ho, S; Cabrera, J; Tran, V; Farre, J; Anderson, R; Sanchez-Quintana, D

    2001-01-01

    BACKGROUND—Radiofrequency ablation of tissues in pulmonary veins can eliminate paroxysmal atrial fibrillation.
OBJECTIVE—To explore the characteristics of normal pulmonary veins so as to provide more information relevant to radiofrequency ablation.
METHODS—20 structurally normal heart specimens were examined grossly. Histological sections were made from 65 pulmonary veins.
RESULTS—The longest myocardial sleeves were found in the superior veins. The sleeves were thickest at the venoatrial junction in the left superior pulmonary veins. For the superior veins, the sleeves were thickest along the inferior walls and thinnest superiorly. The sleeves were composed mainly of circularly or spirally oriented bundles of myocytes with additional bundles that were longitudinally or obliquely oriented, sometimes forming mesh-like arrangements. Fibrotic changes estimated at between 5% and 70% across three transverse sections were seen in 17 veins that were from individuals aged 30 to 72 years.
CONCLUSIONS—The myocardial architecture in normal pulmonary veins is highly variable. The complex arrangement, stretch, and increase in fibrosis may produce greater non-uniform anisotropic properties.


Keywords: arrhythmias; catheter ablation; fibrillation; cardiac veins PMID:11514476

  2. Mathematical modeling of radiofrequency ablation for varicose veins.

    PubMed

    Choi, Sun Young; Kwak, Byung Kook; Seo, Taewon

    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

  3. 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

  4. 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

  5. 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.

  6. Radiofrequency Thermal Ablation in Painful Myeloma of the Clavicle

    PubMed Central

    Imani, Farnad; Vakily, Masoud

    2014-01-01

    A 57-year-old male patient had myeloma. He had severe pain in the left clavicle that did not respond to radiotherapy; therefore, it was treated with radiofrequency thermal ablation (RFTA). Under fluoroscopic guidance, two RF needles at a distance of 1.5 cm from each other were inserted into the mass and conventional radiofrequency (90℃ and 60 seconds) at two different depths (1 cm apart) was applied. Then, 2 ml of 0.5% ropivacaine along with triamcinolone 40 mg was injected in each needle. The visual analogue pain score (VAS from 0 to 10) was decreased from 8 to 0. In the next 3 months of follow-up, the patient was very satisfied with the procedure and the mass gradually became smaller. There were no complications. This study shows that RFTA could be a useful method for pain management in painful osteolytic myeloma lesions in the clavicle. PMID:24478905

  7. Chronic incomplete atrioventricular block induced by radiofrequency catheter ablation

    SciTech Connect

    Huang, S.K.; Bharati, S.; Graham, A.R.; Gorman, G.; Lev, M. )

    1989-10-01

    To determine if catheter ablation of the atrioventricular (AV) junction with radiofrequency energy can induce chronic incomplete (first- and second-degree) AV block to avoid the need for a permanent pacemaker, 20 closed-chest dogs were studied. Group 1 (10 dogs) received radiofrequency energy (750 kHz) with a fixed power setting (5 or 10 W) while increasing the pulse duration from 10 to 50 seconds for each application. Group 2 (10 dogs) received energy with a fixed pulse duration (20 or 30 seconds) while increasing the power setting from 5 to 10 W or from 10 to 20 W during each energy delivery. Radiofrequency energy was delivered between a chest-patch electrode and the distal electrode of a regular 7F tripolar His bundle catheter. For each application, the energy delivery was interrupted when (1) the PR interval prolonged (greater than 50%) or (2) second-degree or complete AV block occurred and persisted up to 5 seconds. The ablation procedure ended when there was (1) persistent PR prolongation (greater than 50%) or persistent second-degree AV block (lasting greater than 30 minutes) after ablation, (2) occurrence of two consecutive transient (less than 1 minute) complete AV blocks after each energy delivery, or (3) complete AV block (lasting greater than 2 minutes) after ablation. Of seven dogs in group 1 and five dogs in group 2 in which incomplete AV block was achieved 1 hour after the procedure, six in group 1 and five in group 2 remained in incomplete AV block 2-3 months after ablation. One dog in group 1 progressed into complete AV block. Of the remaining three dogs in group 1 and five dogs in group 2 in which complete AV block was initially achieved 1 hour after ablation, two in group 1 and four in group 2 continued to have complete AV block, whereas one in each group had AV conduction returned to incomplete at 1-2 months of follow-up.

  8. Excessive Hyperthermic Necrosis of a Pulmonary Lobe after Hypertonic Saline-Enhanced Monopolar Radiofrequency Ablation

    SciTech Connect

    Kim, Tae Sung Lim, Hyo K.; Kim, Hojoong

    2006-02-15

    Although there has been a feasibility study of saline-enhanced radiofrequency ablation of the lung in rabbits, there has been no report on hypertonic saline-enhanced radiofrequency ablation of human pulmonary tumors or its complication. We report a case in which a large necrotic cavity was produced in the lung after hypertonic saline-enhanced radiofrequency ablation of recurrent metastatic tumor from hepatocellular carcinoma. Although hypertonic saline-enhanced radiofrequency ablation is powerful and efficient in local ablation, it is difficult to predict the exact extent of ablation, especially in the lungs. This can be dangerous, as there is a high chance of producing an ablation area much larger than expected and, hence, major complications. Special attention is required not to overablate while using this technique.

  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. Pulmonary Artery Pseudoaneurysm Related to Radiofrequency Ablation of Lung Tumor

    SciTech Connect

    Sakurai, Jun Mimura, Hidefumi; Gobara, Hideo; Hiraki, Takao; Kanazawa, Susumu

    2010-04-15

    We describe a case of pulmonary artery (PA) pseudoaneurysm related to radiofrequency ablation (RFA) of lung tumor. We performed RFA for a pulmonary epithelioid hemangioendothelioma directly adjacent to a branch of the PA. Seventeen days later, the patient complained of hemoptysis. A chest CT image revealed PA pseudoaneurysm. Transcatheter coil embolization was performed 59 days after RFA. Although PA pseudoaneurysm is rare, with an incidence of 0.2% (1/538 sessions) at our institution, it should be recognized as a risk when treating lung tumors adjacent to a branch of the PA.

  11. 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.

  12. Treatment of bone tumours by radiofrequency thermal ablation.

    PubMed

    Santiago, Fernando Ruiz; Del Mar Castellano García, María; Montes, Jose Luis Martínez; García, Manuel Ruiz; Fernández, Juan Miguel Tristán

    2009-03-01

    Radiofrequency thermal ablation (RFTA) is considered the treatment of choice for osteoid osteomas, in which it has long been safely used. Other benign conditions (chondroblastoma, osteoblastoma, giant cell tumour, etc.) can also be treated by this technique, which is less invasive than traditional surgical procedures. RFTA ablation is also an option for the palliation of localized, painful osteolytic metastatic and myeloma lesions. The reduction in pain improves the quality of life of patients with cancer, who often have multiple morbidities and a limited life expectancy. In some cases, these patients are treated with RFTA because conventional therapies (surgery, radiotherapy, chemotherapy, etc.) have been exhausted. In other cases, it is combined with conventional therapies or other percutaneous treatments, e.g., cementoplasty, offering faster pain relief and bone strengthening. A multidisciplinary approach to the management of these patients is recommended to select the optimal treatment, including orthopaedic surgeons, neurosurgeons, medical and radiation oncologists and interventional radiologists. PMID:19468917

  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. Real-time calibration of temperature estimates during radiofrequency ablation.

    PubMed

    Varghese, T; Daniels, M J

    2004-07-01

    Radiofrequency ablation is an interstitial focal ablative therapy that can be used in a percutaneous fashion and permits in situ destruction of hepatic tumors. Recurrence rates after rf therapy are as high as 34-55%, due to difficulties in accurately identifying the zone of necrosis (thermal lesion) because of the low intrinsic acoustic contrast between normal and ablated liver tissue. Our goal is to provide real-time ultrasonic tracking of temperature changes over the large range of temperatures traditionally used (40-100 degrees C) in rfablation procedures using an external ultrasound transducer. Temperature estimates are obtained using a cross-correlation algorithm applied to rf ultrasound echo signal data acquired at discrete intervals during heating. Apparent tissue displacement estimates obtained at these discrete time-intervals are accumulated to obtain a cumulative displacement map, whose gradient provides after appropriate scaling provides a temperature map at the specified elapsed ablation duration. Temperature maps are used to display the initial temperature rise and to continuously update a thermal map of the treated region. In this paper, we develop calibration curves that relate the echo shift due to the change in the speed of sound and thermal expansion to the corresponding temperature increase on in-vitro tissue specimens. These calibration curves can then be utilized for the real time calibration and analysis of temperature estimates obtained from the rf echo signals during ablation. Temperature maps obtained using the calibration curve compare favorably to temperature estimates observed using the invasive thermosensor readings on the ablation electrode and previous results that utilized a linear calibration factor.

  15. Radiofrequency ablation for hepatocellular carcinoma: use of low vs maximal radiofrequency power

    PubMed Central

    Macatula, T C; Lin, C-C; Lin, C-J; Chen, W-T; Lin, S-M

    2012-01-01

    Objectives To investigate whether radiofrequency (RF) ablation with low power (LP) or maximal power (MP) for hepatocellular carcinoma (HCC) can achieve optimal ablation and fewer adverse effects. Methods RF ablation was performed with MP in 101 patients (129 tumours) and with LP in 46 patients (61 tumours). MP RF ablation used power of >120 W. RF power below this was designated as LP. Clinical outcomes were also analysed in subgroups of high-risk tumours near the bile duct and blood vessels. Results Primary effectiveness was achieved in 91.8% in the LP group and 89.9% in the MP group (p=0.795). 1 and 2-year local tumour progression rates were 28% and 30%, respectively, in the LP group, and 24% and 29%, respectively, in the MP group (p=0.70). 1 and 2-year survival rates were 98% and 98%, respectively, in the LP group, and 93% and 90%, respectively, in the MP group (p=0.216). The MP group had more adverse effects, with post-RF ablation syndrome, asymptomatic pleural effusion and ascites, than the LP group (20% vs 39% in the MP group; p=0.027); however, there was no significant difference in major complication rates (6% in the MP and LP groups; p=0.497). Among the patients with high-risk tumours, RF ablation using MP vs LP was comparable in primary effectiveness (91.7% vs 95.2%; p=0.618), local tumour progression (42.9% vs 29.2%; p=0.304) and overall complications (5% vs 8%; p=0.618). Conclusion RF ablation with LP and MP are comparable in clinical outcomes but considerably fewer adverse effects were encountered in the LP group. PMID:21427178

  16. 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

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

    SciTech Connect

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

    2006-04-15

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

  18. Transcatheter radiofrequency ablation of atrial tissue using a suction catheter.

    PubMed

    Lavergne, T; Prunier, L; Cuize, L; Bruneval, P; Von Euw, D; Le Heuzey, J Y; Peronneau, P

    1989-01-01

    Closed chest ablative technique that avoid barotrauma would be attractive for ablation at thin walled cardiac structures, such as the atrial free wall or coronary sinus. Transcatheter radiofrequency (RF) currents produce tissue necrosis the size of which is dependent on the contact between the tissue and the electrode. In order to assess the effects of transvenous RF ablation of atrial free wall using a suction electrode catheter, we delivered in ten dogs, one single unmodulated RF pulse 1.2 MHz, in a unipolar mode, through the distal electrode of a lumen catheter (USCI 8F) (USCI, Billerica, MA USA) located in the right appendage. During the pulse an 80 KPa vacuum depression was applied to the lumen of the catheter. Each pulse had a 10 seconds duration and the mean delivered power was 4.3 +/- 1.4 W. Aortic pressure and electrocardiogram were monitored during the procedure. A right atrial electrophysiological study was performed at the ablated site, at control, after suction application and after RF pulse delivery. The animals were sacrificed after 14 or 21 days. Atrial pacing threshold values decreased after suction application in comparison to control values after the pulse (0.42 +/- 0.06 vs 0.60 +/- 0.23 mA, P less than O.05) but increased after the pulse delivery (2.60 +/- 1.85 mA, P less than 0.01). In contrast, the atrial effective refractory period did not significantly change after suction, nor after RF pulse delivery. Aortic pressure remained unchanged throughout the procedure. Complex arrhythmias were not observed during or after RF pulse delivery. One dog died suddenly at the first day after ablation, but this death was most probably unrelated to RF ablation. Anatomic lesions had a length of 8.8 +/- 3.3 mm, a width of 4.6 +/- 2.5 mm and a depth of 3.6 +/- 1.1 mm. They were transmural in nine of the ten dogs but without atrial wall perforation in any case. Lesions suggesting tissue volatilization were present in four dogs. These results demonstrate that

  19. 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.

  20. A mathematical model of bipolar radiofrequency-induced thermofusion.

    PubMed

    Wagenpfeil, J; Nold, B; Fischer, K; Neugebauer, A; Rothmund, R; Krämer, B; Brucker, S; Mischinger, J; Schwentner, C; Schenk, M; Wallwiener, D; Stenzl, A; Enderle, M; Sawodny, O; Ederer, M

    2014-01-01

    Bipolar radiofrequency-induced thermofusion has become a widely accepted method successfully used in open and particularly in minimally-invasive surgery for the sealing of blood vessels and tissue of up to several millimeters diameter. Despite its wide-spread application, the thermofusion process itself is not well understood on a quantitative and dynamic level, and manufacturers largely rely on trial-and-error methods to improve existing instruments. To predict the effect of alternative generator control strategies and to allow for a more systematic approach to improve thermofusion instruments, a mathematical model of the thermofusion process is developed. The system equations describe the spatial and temporal evolution of the tissue temperature due to Joule heating and heat transfer, and the loss of tissue water due to vaporization. The resulting effects on the tissue properties, most importantly the electrical resistivity, heat capacity and thermal conductivity, are considered as well. Experimental results indicate that the extent of the lateral thermal damage is directly affected by Joule heating of the lateral tissue. The experimental findings are supported by simulation results using the proposed mathematical model of thermofusion. PMID:25571285

  1. 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.

  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.

  4. 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

  5. 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.

  6. Palliation of Soft Tissue Cancer Pain With Radiofrequency Ablation

    PubMed Central

    Locklin, Julia K.; Mannes, Andrew; Berger, Ann; Wood, Bradford J.

    2008-01-01

    The purpose of this study was to analyze the feasibility, safety, and efficacy of radiofrequency ablation (RFA) to treat pain from soft tissue neoplasms. RFA was performed on 15 painful soft tissue tumors in 14 patients. Tumors varied in histology and location and ranged in size from 2 to 20 cm. Patient pain was assessed using the Brief Pain Inventory (BPI) at baseline and 1 day, 1 week, 1 month, and 3 months post RFA. All patients had unresectable tumors or were poor operative candidates whose pain was poorly controlled by conventional treatment methods. BPI scores were divided into two categories: pain severity and interference of pain. Although not all scores were statistically significant, all mean scores trended down with increased time post ablation. Based on these outcomes, RFA appears to be a low-risk and well-tolerated procedure for pain palliation in patients with unresectable, painful soft tissue neoplasms. RFA is effective for short-term local pain control and may provide another option for failed chemotherapy or radiation therapy in patients with cancer. However, pain may transiently worsen, and relief is often temporary. PMID:15524075

  7. 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.

  8. 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

  9. 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

  10. 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

  11. Reversal of ventricular premature beat induced cardiomyopathy by radiofrequency catheter ablation.

    PubMed

    Blaauw, Y; Pison, L; van Opstal, J M; Dennert, R M; Heesen, W F; Crijns, H J G M

    2010-10-01

    Frequent monomorphic ventricular premature beats (VPBs) may lead to left ventricular dysfunction. We describe two patients with frequent monomorphic VPBs and dilated cardiomyopathy in whom left ventricular function normalised after elimination of the VPBs by radiofrequency catheter ablation. The recent literature on this topic is summarised and potential candidates for catheter ablation are discussed. (Neth Heart J 2010;18:493-8.).

  12. 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.

  13. 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.

  14. 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.

  15. Analysis and analytical characterization of bioheat transfer during radiofrequency ablation.

    PubMed

    Wang, Keyong; Tavakkoli, Fatemeh; Wang, Shujuan; Vafai, Kambiz

    2015-04-13

    Understanding thermal transport and temperature distribution within biological organs is important for therapeutic aspects related to hyperthermia treatments such as radiofrequency ablation (RFA). Unlike surface heating, the RFA treatment volumetrically heats up the biological media using a heating probe which provides the input energy. In this situation, the shape of the affected region is annular, which is described by an axisymmetric geometry. To better understand the temperature responses of the living tissues subject to RFA, comprehensive characteristics of bioheat transport through the annular biological medium is presented under local thermal non-equilibrium (LTNE) condition. Following the operational features of the RFA treatment, based on the porous media theory, analytical solutions have been derived for the blood and tissue temperature distributions as well as an overall heat exchange correlation in cylindrical coordinates. Our analytical results have been validated against three limiting cases which exist in the literature. The effects of various physiological parameters, such as metabolic heat generation, volume fraction of the vascular space, ratio of the effective blood to tissue conductivities, different biological media and the rate of heat exchange between the lumen and the tissue are investigated. Solutions developed in this study are valuable for thermal therapy planning of RFA. A criterion is also established to link deep heating protocol to surface heating.

  16. 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

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. 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

  3. Local carboplatin delivery and tissue distribution in livers after radiofrequency ablation.

    PubMed

    Szymanski-Exner, A; Gallacher, A; Stowe, N T; Weinberg, B; Haaga, J R; Gao, J

    2003-11-01

    This study investigated the local drug pharmacokinetics of intralesional drug delivery after radiofrequency ablation of the liver. We hypothesized that the tissue architecture damaged by the ablation process facilitates the drug penetration in the liver and potentially enlarges the therapeutic margin in the local treatment of cancer. The delivery rate and tissue distribution of carboplatin, an anticancer agent, released from poly(D,L-lactide-co-glycolide) implants into rat livers after radiofrequency ablation were quantified by atomic absorption spectroscopy. Results showed that carboplatin clearance through blood perfusion was significantly slower in the ablated livers, leading to a more extensive tissue retention and distribution of the drug. The concentration of Pt at the implant-tissue interface ranged from 234 to 1440 microg Pt/(g liver) in the ablated livers over 144 h versus 56 to 177 microg Pt/(g liver) in the normal tissue. The maximum penetration distance at which Pt level reached above 6 microg/g (calculated based on a reported IC90 value for carboplatin) was 8-10 mm and 4-6 mm in ablated and normal liver, respectively. Histological analysis of the necrotic lesions showed widespread destruction of tissue structure and vasculature, supporting the initial hypothesis. This study demonstrated that intralesional drug delivery could provide a sustained, elevated concentration of anticancer drug at the ablation boundary that has the potential to eliminate residual cancer cells surviving radiofrequency ablation. PMID:14566792

  4. 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

  5. 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

  6. 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

  7. 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.

  8. 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

  9. Fluoroscopy-guided Bipolar Radiofrequency Thermocoagulation Treatment for Discogenic Low Back Pain

    PubMed Central

    Zhang, Li; Ding, Xin-Li; Zhao, Xu-Li; Wang, Jun-Nan; Li, Yan-Ping; Tian, Ming

    2016-01-01

    Background: The efficacy of percutaneous intradiscal radiofrequency thermocoagulation (PIRFT) for the treatment of discogenic low back pain (LBP) remains controversial. However, all the PIRFT studies utilized monopolar radiofrequency thermocoagulation (RFTC). The aim of this study was to investigate the safety and efficacy of bipolar RFTC for the treatment of discogenic LBP. Methods: A total of 23 patients with discogenic LBP were treated with single-level bipolar RFTC. The patients were assessed before the procedure and at 1 week, 1 month, 3 months, 6 months, and 1 year after the procedure. The primary outcome included the visual analog scale (VAS) score and the Oswestry Disability Index (ODI) score. The secondary outcome included pain relief, reduction of analgesic dose, and patient satisfaction. Results: The VAS and ODI scores were significantly decreased after bipolar RFTC treatment at all time points of follow-up (P < 0.05). Bipolar RFTC treatment also resulted in a significant change in all secondary measures, such as pain relief, reduction of analgesic dose, and patient satisfaction. No serious complications or neurological sequelae were observed in any of the patients. Conclusions: Bipolar RFTC treatment can significantly attenuate pain and improve the function of patients with discogenic LBP. PMID:27647190

  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. Repeated radiofrequency ablation of atrial tachycardia in restrictive cardiomyopathy secondary to myofibrillar myopathy.

    PubMed

    Stöllberger, Claudia; Gatterer, Edmund; Finsterer, Josef; Kuck, Karl-Heinz; Tilz, Roland Richard

    2014-08-01

    Myofibrillar myopathy is characterized by nonhyaline and hyaline lesions due to mutations in nuclear genes encoding for extra-myofibrillar or myofibrillar proteins. Cardiac involvement in myofibrillar myopathy may be phenotypically expressed as dilated, hypertrophic, or restrictive cardiomyopathy. Radiofrequency ablation of atrial fibrillation and flutter has so far not been reported in myofibrillar myopathy. We report the case of a young female with myofibrillar myopathy and deteriorating heart failure due to restrictive cardiomyopathy and recurrent atrial fibrillation and atrial tachycardias intolerant to pharmacotherapy. Cardiac arrhythmias were successfully treated with repeat radiofrequency ablations and resulted in regression of heart failure, thus postponing the necessity for cardiac transplantation.

  12. 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.

  13. 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.

  14. Successful control of life-threatening polymorphic ventricular tachycardia by radiofrequency catheter ablation in an infant.

    PubMed

    Abe, Yuriko; Sumitomo, Naokata; Okuma, Hiromi; Nakamura, Takahiro; Fukuhara, Junji; Ichikawa, Rie; Matsumura, Masaharu; Miyashita, Michio; Kamiyama, Hiroshi; Ayusawa, Mamoru; Watanabe, Mamie; Joo, Kunitaka; Makita, Naomasa; Horie, Minoru

    2014-05-01

    We present a case of a 9-month-old girl in whom malignant polymorphic ventricular tachycardia (VT) was successfully controlled by radiofrequency catheter ablation under guidance with a three-dimensional mapping system. The VTs originated from the left ventricular lateral wall, left ventricular anterior wall, and left ventricular apex. At least six types of VTs were documented during the electrophysiology study. All VTs were successfully controlled after two sessions of radiofrequency catheter ablation, and she was discharged from our hospital on propranolol, mexiletine, flecainide, and aprindine. PMID:23836069

  15. Life-Threatening Hematuria Requiring Transcatheter Embolization Following Radiofrequency Ablation of Renal Cell Carcinoma

    SciTech Connect

    Roach, H.; Whittlestone, T.; Callaway, M.P.

    2006-08-15

    Radiofrequency ablation is increasingly being acknowledged as a valid treatment for renal cell carcinoma in patients in whom definitive curative resection is deemed either undesirable or unsafe. A number of published series have shown the technique to have encouraging results and relatively low complication rates. In this article, we report a case of delayed life-threatening hematuria requiring transcatheter embolization of a bleeding intrarenal artery in a patient who had undergone imaging-guided radiofrequency ablation of a 3 cm renal cell carcinoma. To our knowledge, such a complication has not been reported previously.

  16. Effect of percutaneous renal sympathetic nerve radiofrequency ablation in patients with severe heart failure.

    PubMed

    Dai, Qiming; Lu, Jing; Wang, Benwen; Ma, Genshan

    2015-01-01

    This study aimed to investigate the clinical feasibility and effects of percutaneous renal sympathetic nerve radiofrequency ablation in patients with heart failure. A total of 20 patients with heart failure were enrolled, aged from 47 to 75 years (63±10 years). They were divided into the standard therapy (n = 10), and renal nerve radiofrequency ablation groups (n = 10). There were 15 males and 5 female patients, including 8 ischemic cardiomyopathy, 8 dilated cardiomyopathy, and 8 hypertensive cardiopathy. All of the patients met the criteria of New York Heart Association classes III-IV cardiac function. Patients with diabetes and renal failure were excluded. Percutaneous renal sympathetic nerve radiofrequency ablation was performed on the renal artery wall under X-ray guidance. Serum electrolytes, neurohormones, and 24 h urine volume were recorded 24 h before and after the operation. Echocardiograms were performed to obtain left ventricular ejection fraction at baseline and 6 months. Heart rate, blood pressure, symptoms of dyspnea and edema were also monitored. After renal nerve ablation, 24 h urine volume was increased, while neurohormone levels were decreased compared with those of pre-operation and standard therapy. No obvious change in heart rate or blood pressure was recorded. Symptoms of heart failure were improved in patients after the operation. No complications were recorded in the study. Percutaneous renal sympathetic nerve radiofrequency ablation may be a feasible, safe, and effective treatment for the patients with severe congestive heart failure.

  17. Precision test apparatus for evaluating the heating pattern of radiofrequency ablation devices.

    PubMed

    Chang, I; Beard, B

    2002-11-01

    Radiofrequency has established itself as a useful technique for managing cardiac arrhythmias and treating soft tissue tumors. However, despite its pervasive use, many of the biophysical principals needed to fully understand and optimize the radiofrequency ablation technique have not been explored. We have designed a test rig that is useful for studying the heat transfer mechanisms that affect the outcome of radiofrequency ablation devices. Using both solid and liquid phantom materials, which simulate body tissues and blood, the test rig is designed for systematic testing of the effects of predictable flow patterns on the temperature profiles generated within the solid phantom. The test rig consists of a custom built thermistor array, a linear test chamber, and a radiofrequency generator. We calibrate the flow of a liquid phantom material to demonstrate that predictable laminar flow profiles are generated. To demonstrate the performance of the ablation system, we present preliminary data attained using a commercially available cardiac ablation catheter. The advantages of this test system are its flexibility, its reproducibility, its precision, and its low cost. Thus, it is ideally suited for studying a variety of complex ablation problems involving multiple tissues types and complex blood flow geometries.

  18. 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

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

    PubMed Central

    Luo, Xin; Shu, Shan-rong; Ma, Xue-feng; Shuai, Han-lin

    2015-01-01

    Abstract 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

  20. 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

  1. Radiofrequency Ablation Versus Partial Nephrectomy in Treating Small Renal Tumors

    PubMed Central

    Yin, Xiaotao; Cui, Liang; Li, Fanglong; Qi, Siyong; Yin, Zhaoyang; Gao, Jiangping

    2015-01-01

    Abstract Radiofrequency ablation (RFA) has emerged as an alternative treatment to surgical partial nephrectomy (PN) in the treatment of small renal tumors (SRTs). But its safety and oncological efficacy are still controversial. We conducted this systematic review and meta-analysis to compare the peritoperative and oncological outcomes of RFA and PN in the treatment of SRTs. Pubmed, EMBASE, Cochrane CENTRAL, and Web of Science were searched to identify eligible studies that compared the RFA and PN in the treatment of SRTs. Twelve retrospective studies that compared RFA with PN in the treatment of SRTs met our selection criterion and were included in this meta-analysis. The pooled results indicated that the local recurrence rate (4.14% vs 4.10%, RR: 1.18, 95% CI: 0.68, 2.07, P = 0.550) and distant metastases rate (2.76% vs 1.89%, RR: 1.31, 95% CI: 0.70, 2.46, P = 0.686) were not significantly different between the RFA group and the PN group. In terms of perioperative outcomes, RFA was associated with shorter length of stay (LOS) (WMD: −2.02 days, 95% CI: −2.77, −1.27, P < 0.001), lower eGFR decline after treatment (WMD: −3.90, 95% CI: −6.660, −1.140, P = 0.006). However, the overall perioperative complication rate (7.5% vs 6.2%, RR:1.10, 95% CI: 0.64, 1.87, P = 0.740) and the major complication rate (3.7% vs 4.4%, RR: 0.83, 95% CI: 0.43, 1.60, P = 0.579) were both similar between RFA and PN groups. Compared with PN, RFA achieves an equal oncological outcome for SRTs with similar local recurrence rate and distant metastases rate. Additionally, RFA is associated with a similar perioperative complication rate, lower decline of eGFR, and shorter LOS. Therefore, RFA is an effective option in the treatment of SRTs for selected patients. PMID:26683944

  2. 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.

  3. Radio-frequency ablation of small renal tumors: minimum follow up of 1 year

    NASA Astrophysics Data System (ADS)

    Patel, Vipul; Thaly, Rahul; Shah, Ketul

    2007-02-01

    OBJECTIVE: With the increased utility of complex imaging modalities small renal tumors are being diagnosed with rising frequency. We performed radiofrequency ablation to treat tumors less than 4cm in size using a combination of temperature, impedance, ultrasound and laparoscopic guidance. In this article we reviewed the outcome of radiofrequency ablation of renal tumors at one year at our institution. MATERIALS AND METHODS: Over a three-year period 75 patients with a total of 93 renal tumors underwent radiofrequency ablation. Average patient age was 64.5 years with ASA of 2.9. Indications for nephron sparing were imperative in 33 (solitary kidney 21, renal insufficiency 12). Seventeen patients had significant co-morbidities with ASA score of 3 or more and were thought to be poor candidates for nephrectomy or partial nephrectomy. Five were Jehovah's Witness patients. Average tumor size was 3.2 cm (1.5-4.0). 60% of the tumors were exophytic and 40% deep. Radiofrequency ablation was performed via a transperitoneal approach using the single pronged 3cm Cool tip electrode (Radionics Inc). Tumor was isolated laparoscopically. Prior to ablation the lesions were biopsied. Ablation was performed using both laparoscopic and real-time ultrasound imaging of the boarders of the tumor. During ablation impedance and temperature monitoring was performed. For each tumor two separate ablations were performed at perpendicular angles, the first ablation was for 6 minutes and the second for 3 minutes. The center and periphery of the tumor was monitored to insure that the temperature rose above 70 degrees Celsius. Patients were followed at three-month intervals with triple phase CT scan or MRI to evaluate efficacy of the ablation. Our criteria for recurrent tumor were growth or enhancement of the lesion. RESULTS: Average operative time was 109 minutes with and average EBL of <25cc. Mean hospital stay was 1.4 days. At average follow up of 19.2 months (range 2-24), one lesion showed

  4. 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.

  5. Reversal of premature ventricular complex-induced cardiomyopathy following successful radiofrequency catheter ablation.

    PubMed

    Efremidis, Michalis; Letsas, Konstantinos P; Sideris, Antonios; Kardaras, Fotios

    2008-06-01

    Premature ventricular complex (PVC)-induced cardiomyopathy is an underappreciated cause of left-ventricular (LV) dysfunction. The present report describes the case of an elderly man with a very high burden of monomorphic PVCs and LV dysfunction. Elimination of the left ventricular focus following radiofrequency catheter ablation resulted in reversal of cardiomyopathy.

  6. Radiofrequency ablation of drug-resistant cancer cells using molecularly targeted carboxyl-functionalized biodegradable graphene.

    PubMed

    Sasidharan, Abhilash; Sivaram, Amal J; Retnakumari, Archana P; Chandran, Parwathy; Malarvizhi, Giridharan Loghanathan; Nair, Shantikumar; Koyakutty, Manzoor

    2015-04-01

    Under ultralow radiofrequency (RF) power, transferrin-conjugated graphene nanoparticles can thermally ablate drug- or radiation-resistant cancer cells very effectively. The results suggest that graphene-based RF hyperthermia can be an efficient method to manage drug-/radiation-resistant cancers. PMID:25586821

  7. [Radiofrequency ablation in ventricular tachycardia: initial experience and evaluation of its limitations].

    PubMed

    Velázquez, E; Rosas, F; Frank, R; Tonet, J; Fontaine, G; Lascault, G; Gallais, Y

    1994-01-01

    The purpose of this paper is to report our initial experience with radiofrequency catheter ablation in 21 patients with ventricular tachycardia of different etiologies and to evaluate the causes which play a role in its limitation. The results show a low rate of effectiveness: total clinical success of 43%. Nevertheless there was a high success rate in a specific subsets of patients. The results depends on several factors: the electrophysiologic mechanisms and substrates of the tachycardia, the criteria to localize the critical area perpetuating the arrhythmia and the biophysical aspects of radiofrequency energy. Its usefulness is manifested in ventricular tachycardia with structurally normal heart and it has a limited success in cases with organic heart disease. Improvement of technical aspects and better understanding of the mechanisms of the tachycardia and characteristics of the target site will enhance the results of radiofrequency catheter ablation in ventricular tachycardia. PMID:7979818

  8. In vitro assessment of a combined radiofrequency ablation and cryo-anchoring catheter for treatment of mitral valve prolapse.

    PubMed

    Boronyak, Steven M; Merryman, W David

    2014-03-21

    Percutaneous approaches to mitral valve repair are an attractive alternative to surgical repair or replacement. Radiofrequency ablation has the potential to approximate surgical leaflet resection by using resistive heating to reduce leaflet size, and cryogenic temperatures on a percutaneous catheter can potentially be used to reversibly adhere to moving mitral valve leaflets for reliable application of radiofrequency energy. We tested a combined cryo-anchoring and radiofrequency ablation catheter using excised porcine mitral valves placed in a left heart flow loop capable of reproducing physiologic pressure and flow waveforms. Transmitral flow and pressure were monitored during the cryo-anchoring procedure and compared to baseline flow conditions, and the extent of radiofrequency energy delivery to the mitral valve was assessed post-treatment. Long term durability of radiofrequency ablation treatment was assessed using statically treated leaflets placed in a stretch bioreactor for four weeks. Transmitral flow and pressure waveforms were largely unaltered during cryo-anchoring. Parameter fitting to mechanical data from leaflets treated with radiofrequency ablation and cryo-anchoring revealed significant mechanical differences from untreated leaflets, demonstrating successful ablation of mitral valves in a hemodynamic environment. Picrosirius red staining showed clear differences in morphology and collagen birefringence between treated and untreated leaflets. The durability study indicated that statically treated leaflets did not significantly change size or mechanics over four weeks. A cryo-anchoring and radiofrequency ablation catheter can adhere to and ablate mitral valve leaflets in a physiologic hemodynamic environment, providing a possible percutaneous alternative to surgical leaflet resection of mitral valve tissue.

  9. Percutaneous Radiofrequency Ablation of Lung Tumors: Difficulty Withdrawing the Hooks Resulting in a Split Needle

    SciTech Connect

    Steinke, Karin King, Julie; Glenn, Derek; Morris, David L.

    2003-11-15

    We describe a most unusual problem of a split needle following a lung radiofrequency ablation (RFA) procedure. We encountered the problem when retracting the electrode hooks into the shaft at completion of the ablation. We describe the process we adopted to overcome this problem. Charring of the ablated tissue can cause the tissue to become caught in the space between the hooks and the shaft or stick to the hooks. This can prevent withdrawal of the hooks into the shaft and is therefore an important complication of which practitioners need to be aware.

  10. Radiofrequency ablation of the supra-orbital nerve in the treatment algorithm of hemicrania continua.

    PubMed

    Weyker, Paul; Webb, Christopher; Mathew, Leena

    2012-01-01

    Hemicrania continua (HC) is an uncommon primary headache disorder in which the diagnosis centers on unilaterality and its absolute responsiveness to indomethacin. We describe 3 patients with a long standing history of headache diagnosed as hemicrania continua. There was profound response to indomethacin which was limited by side effects. In one patient the therapy with indomethacin was limited secondary to co-morbidities. Initial diagnostic blockade provided significant relief of symptoms based on which radio-frequency ablation of the supraorbital nerve was performed with substantial improvement in symptoms. Traditionally, hemicrania continua has been managed exclusively with oral analgesics and is defined by its singular response to indomethacin. Radio-frequency ablation (RFA) has been reported in the literature for multiple indications. This case series is unique in that it describes 3 patients diagnosed with hemicrania continua with pain referred in the supraorbital nerve distribution, who underwent radiofrequency ablation of the supraorbital nerve with resultant resolution of headaches. Traditionally, hemicrania continua has been managed exclusively with oral analgesics and is defined by its singular response to indomethacin. This report is unique in that it describes three patients diagnosed with hemicrania continua with pain referred in the supraorbital nerve distribution who underwent radiofrequency ablation of the supraorbital nerve with resultant resolution of headaches. After the RFA medical management was minimal to none in both patients. Though the utility and cost efficacy of RFA of peripheral nerves needs to be confirmed in well-designed trials we present these cases as an example of how this minimally invasive technique can safely provide analgesia in a difficult to treat cephalgia. Moreover if precise anatomical localization of the headache is possible then diagnostic blockade of the appropriate peripheral nerve may be performed followed by

  11. 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

  12. [Treatment of pulmonary vein stenosis secondary to radiofrequency ablation].

    PubMed

    Ferrero Guadagnoli, Adolfo; Contreras, Alejandro E; Leonardi, Carlos R; Ballarino, Miguel A; Atea, Leonardo; Peirone, Alejandro R

    2014-01-01

    Isolation of the pulmonary veins by applying radiofrequency is an effective treatment for atrial fibrillation. One of the potential complications with higher clinical compromise utilizing this invasive technique is the occurrence of stenosis of one or more pulmonary veins. This complication can be treated by angioplasty with or without stent implantation, with an adequate clinical improvement, but with a high rate of restenosis.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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

  1. Bipolar radiofrequency lesion geometry: implications for palisade treatment of sacroiliac joint pain.

    PubMed

    Cosman, Eric R; Gonzalez, Christian D

    2011-01-01

    Ex vivo photographic temperature mapping of bipolar radiofrequency (RF) lesions in animal tissue is performed over a wide range of electrode tip spacings, tip lengths, tip diameters, tip temperatures, and lesion times. In vivo temperature measurements collected during clinical treatment of sacroiliac joint (SIJ) pain corroborate those collected ex vivo. Generation of a "strip lesion" connecting two separated bipolar electrode tips is demonstrated ex vivo for tip spacings as large as 20 mm. A rounded rectangular bipolar lesion with midline dimensions 12 mm × 15 mm × 8 mm (L × W × D) is demonstrated using 10 mm parallel tip spacing, 10 mm tip lengths, 20 gauge cannulae, 90°C tip temperature, and 3-minute lesion time. Lesion length can be increased to 18 mm by using 15 mm tip lengths. Lesion width can be increased to 17 mm by using 12 mm tip spacing. The size of conventional bipolar lesions can exceed the size of lesions produced both by conventional monopolar RF (12 mm × 7 mm × 7 mm ellipsoidal) and by cooled monopolar RF as used in spinal pain management (10 mm × 10 mm × 10 mm spherical). SIJ pain is treated by placing 5 to 7 straight RF cannulae perpendicular to the dorsal sacrum and producing 4 to 6 overlapping bipolar RF lesions between the dorsal sacral foramina and the ipsilateral SIJ. This bipolar "palisade" (a defensive fence) creates a continuous lesion spanning the region through which multiple sacral lateral branch nerves travel along irregular, branching paths to reach the SIJ.

  2. [The radiofrequency ablation of accessory pathways. The initial experience in Mexico].

    PubMed

    Molina, L; Morales, A; Alvarez, L M; Avila, L

    1993-01-01

    Thirteen patients with paroxysmal supraventricular tachycardia (SVT) due to an accessory pathway were submitted to an electrophysiological study and radiofrequency ablation of the Kent bundle. There were 9 males and 4 females. The mean age was 22 years. Other than their SVT, none had any structural heart disease. Ten of them had Wolff-Parkinson-White syndrome, and three had concealed accessory pathways. Two different types of radiofrequency devices were used: one generating damped sinusoid waves, and two other generators producing pure continuous sinusoid waves. With the first type, two attempts were made: one patient with a concealed pathway and one with overt preexcitation. The successful ablation was not achieved because this wave type is 100 times more powerful, it desiccates the tissue, and thus does not produce the right kind of lesion. The other eleven patients were divided in three groups: I) With left overt preexcitation (7 pts) II) Concealed left Kent bundles (2 pts) III) Right Kent bundles. Ablation was 100% successful in group I, while in the other two groups, only one patient of each was successfully ablated. The overall successful rate of these 3 groups was 81.8%. Of the two patients that could not be treated, one had an anterior septal Kent bundle and the other had a concealed left Kent bundle. We believe that catheter ablation is a very promising therapeutic procedure for patients with SVT, besides being a extraordinary instrument that will enable us to be able to understand further clinical electrophysiology. PMID:8466363

  3. 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.

  4. Finite element modeling of cooled-tip probe radiofrequency ablation processes in liver tissue.

    PubMed

    Barauskas, Rimantas; Gulbinas, Antanas; Vanagas, Tomas; Barauskas, Giedrius

    2008-06-01

    Finite element model of radiofrequency ablation (RFA) with cooled-tip probe in liver has been developed by employing COMSOL Multiphysics software. It describes coupled electric, thermal and sodium chloride solution infiltration flow phenomena taking place during ablation processes. Features of hydraulic capacity, saturation of the tissue by infiltration, and dependency of electrical conductivity on the damage integral of the tissue have been supplied to the model. RFA experiments have validated the model. Physical parameters describing hydraulic capacity and hydraulic conductivity in the tissue, as well as, the relation of electrical conductivity against the value of damage integral have been determined.

  5. Percutaneous radiofrequency ablation-induced perinephric hematoma with acute renal failure in a solitary kidney.

    PubMed

    Zhao, Lee C; Chan, Sarah W; Macejko, Amanda M; Lin, William W

    2008-07-01

    Iatrogenic occurrences (including radiologically guided renal biopsy, shockwave lithotripsy, and minimally invasive ablative procedures) of subcapsular hematoma that lead to acute renal failure are rare but serious. The advancement of minimally invasive procedures has led to an increase in this complication, especially in patients with a solitary kidney. Fortunately, prompt surgical evacuation of the hematoma in these patients allows decompression of the renal parenchyma and recovery of renal function. We report a case of acute renal failure in a patient with a solitary kidney that resulted from a subcapsular hematoma as a complication of radiofrequency ablation.

  6. 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.

  7. [Tachycardia-induced tachycardia: definitive treatment with radiofrequency ablation. Presentation of three cases].

    PubMed

    Velarde, J L; Martellotto, R; Colque, R; Sued, R; Pieroni, M; Volmaro, A; Torné, J

    1999-08-01

    Tachycardia-induced tachycardia is the phenomenon in which one tachycardia degenerates into another. Few data are available in patients suffering from AV nodal reentrant tachycardia an atrial fibrillation. For related to AV nodal reentrant triggered by tachycardia; there is a possible effective treatment by eliminating the slow nodal pathway, with radiofrequency ablation, as shown by other authors. In this study we present data on three patients with repeated episodes of documented atrial fibrillation and at least one episode of AV nodal reentrant tachycardia or regular palpitations. Radiofrequency ablation of the slow AV nodal pathway was successfully performed in both, and at a follow up of 6, 9 and 10 months, respectively, no new episode of AV nodal reentrant tachycardia or atrial fibrillation was documented. PMID:10439662

  8. 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.

  9. Lingual tonsil hypertrophy causing severe dysphagia: treatment with plasma-mediated radiofrequency-based ablation (Coblation).

    PubMed

    Mowry, Sarah E; Ament, Marvin; Shapiro, Nina L

    2010-03-01

    Lingual tonsil hypertrophy is an uncommon cause of upper aerodigestive tract pathology. We present the case of a 17-year-old boy who developed severe dysphagia and subsequent weight loss as a result of lingual tonsil hypertrophy. He was successfully treated with plasma-mediated radiofrequency-based ablation (Coblation). In the past, traditional surgical procedures for lingual tonsil hypertrophy were difficult to perform and recovery was difficult, but the introduction of Coblation has made lingual tonsillectomy much easier.

  10. 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.

  11. Comparison of Internally Cooled Wet Electrode and Hepatic Vascular Inflow Occlusion Method for Hepatic Radiofrequency Ablation

    PubMed Central

    Park, Mi-Hyun; Shin, Byung Seok; Jeon, Gyeong Sik; Lee, Byungmo; Lee, Kichang

    2012-01-01

    Background/Aims Various strategies to expand the ablation zone have been attempted using hepatic radiofrequency ablation (RFA). The optimal strategy, however, is unknown. We compared hepatic RFA with an internally cooled wet (ICW) electrode and vascular inflow occlusion. Methods Eight dogs were assigned to one of three groups: only RFA using an internally cooled electrode (group A), RFA using an ICW electrode (group B), and RFA using an internally cooled electrode with the Pringle maneuver (group C). The ablation zone diameters were measured on the gross specimens, and the volume of the ablation zone was calculated. Results The ablation zone volume was greatest in group B (1.82±1.23 cm3), followed by group C (1.22±0.47 cm3), and then group A (0.48±0.33 cm3). The volumes for group B were significantly larger than the volumes for group A (p=0.030). There was no significant difference in the volumes between groups A and C (p=0.079) and between groups B and C (p=0.827). Conclusions Both the usage of an ICW electrode and hepatic vascular occlusion effectively expanded the ablation zone. The use of an ICW electrode induced a larger ablation zone with easy handling compared with using hepatic vascular occlusion, although this difference was not statistically significant. PMID:23170152

  12. 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

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

    PubMed

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

    2016-04-01

    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.

  14. 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

  15. Radio-frequency current application in bipolar technique for interstitial thermotherapy (rf-ITT)

    NASA Astrophysics Data System (ADS)

    Desinger, Kai; Stein, Thomas; Mueller, Gerhard J.

    1996-12-01

    For the interstitial treatment of pathologic tissue, e.g. tumors, the benign prostate hyperplasia or the concha hyperplasia in otorhinolaryngology, the method of interstitial laser photocoagulation and the monopolar RF- needle coagulation can be used as well as other methods, e.g. the microwave exposure, alcohol injection, ultrasound or hot water irrigation. This article will present latest results of interstitial thermotherapy with radio-frequency alternating current in bipolar technique. Therefore basic investigations of the thermal field distribution in in vitro samples were performed. THe efficiency of the developed applicators were examined using egg white and in in vitro experiments with porcine liver tissue. Bipolar needles with different diameters were built and tested. Carbonization and dehydration can be avoided by irrigation of the tissue during treatment through an integrated central flushing port. A bipolar needle has been developed for the treatment of concha hyperplasia which can be used as the monopolar pendant with similar results in partial tissue coagulation but without current flow in the sensitive head region. First pathologic investigations pointed out that with the use of the bipolar technique the surface of the concha with the ciliary epithelium is less affected due tot he limited spatial current distribution. Furthermore the design of a multi-electrode needle is presented which could probably offer an additional increase of safety and a simplification of performing a concha coagulation procedure. The new design of a bipolar needle electrode enables the surgeon the use of a partial application of radio frequency current for ITT. Less power is needed due to the limited current distribution at the immediate operation site, which means that a neutral electrode is not needed. Thus a highly safe procedure can be performed by the surgeon.

  16. Computed tomography-guided percutaneous radiofrequency ablation of osteoid osteoma: local experience.

    PubMed

    Yip, P S C; Lam, Y L; Chan, M K; Shu, J S J; Lai, K C; So, Y C

    2006-08-01

    Osteoid osteoma is a slow-growing tumour with limited growth potential. In the past, treatment comprised open surgery with en-bloc resection or curettage of the tumour. In recent years, various minimally invasive percutaneous treatments have gained popularity. We report on six patients who underwent computed tomography-guided percutaneous radiofrequency ablations of osteoid osteomas between January 2000 and December 2003 in a regional hospital in Hong Kong. Technical success was achieved in all procedures, with a mean follow-up of 40 months (range, 18-65 months). Five of the six patients achieved complete pain relief after the procedure and remained pain-free on subsequent follow-up. One patient with persistent symptoms after the first ablation was successfully treated with a second ablation. The mean in-hospital stay was 2.4 days. Progress in radiological healing was observed in all patients. There was one complication of skin burn over the needle entry site. Our experience shows that percutaneous computed tomography-guided radiofrequency ablation is a minimally invasive and cost-effective treatment for osteoid osteoma.

  17. 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.

  18. 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.

  19. 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

  20. Probabilistic finite element analysis of radiofrequency liver ablation using the unscented transform

    NASA Astrophysics Data System (ADS)

    dos Santos, Icaro; Haemmerich, Dieter; Schutt, David; Ferreira da Rocha, Adson; Rax Menezes, Leonardo

    2009-02-01

    The main limitation of radiofrequency (RF) ablation numerical simulations reported in the literature is their failure to provide statistical results based on the statistical variability of tissue thermal-electrical parameters. This work developed an efficient probabilistic approach to hepatic RF ablation in order to statistically evaluate the effect of four thermal-electrical properties of liver tissue on the uncertainty of the ablation zone dimensions: thermal conductivity, specific heat, blood perfusion and electrical conductivity. A deterministic thermal-electrical finite element model of a monopolar electrode inserted in the liver was coupled with the unscented transform method in order to obtain coagulation zone confidence intervals, probability and cumulative density functions. The coagulation zone volume, diameter and length were 10.96 cm3, 2.17 cm and 4.08 cm, respectively (P < 0.01). Furthermore, a probabilistic sensitivity analysis showed that perfusion and thermal conductivity account for >95% of the variability in coagulation zone volume, diameter and length.

  1. 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.

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

    PubMed Central

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

    2016-01-01

    Abstract 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

  3. Real-time spectroscopic assessment of thermal damage: implications for radiofrequency ablation.

    PubMed

    Anderson, Christopher D; Lin, Wei-Chiang; Buttemere, Clay R; Washington, M Kay; Mahadevan-Jansen, Anita; Pierce, Janene; Nicoud, Ian B; Pinson, C Wright; Chari, Ravi S

    2004-01-01

    Radiofrequency ablation (RFA) is an evolving technology used to treat unresectable liver tumors. Currently, there is no accurate method to determine RFA margins in real-time during the procedure. We hypothesized that a fiber-optic based spectroscopic monitoring system could detect thermal damage from RFA in real-time. Fluorescence (F) and diffuse reflectance (Rd) spectra were continuously acquired from within the expected ablation zone during canine hepatic RFA using a fiber-optic microinterrogation probe (MIP). The F and Rd spectral feedback were continuously monitored and ablations were stopped based on changes in spectra alone. After each ablation, the MIP tract was marked with India ink and the ablation zone was excised. The relationship of the MIP to the zone of ablation was examined grossly and microscopically. F and Rd spectral changes occurred in three characteristic phases as the ablation zone progresses past the MIP. Phase 1 indicates minimal deviation from normal lives. Phase 2 occurs as the MIP lies within the hemorrhagic zone of the ablated tissue. Phase 3 correlates with complete tissue coagulation. The absolute magnitude of spectral change correlates with the gross and histologic degree of thermal damage. Optical spectroscopy is a technology that allows real-time detection of thermal tissue damage. In this study, both F and Rd spectroscopy accurately defined the advancing hemorrhagic edge of the zone of ablation and the central coagulation zone. These results suggest that F and Rd spectroscopy can be used to create a real-time feedback system to accurately define RFA margins. PMID:15358325

  4. 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

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

    PubMed Central

    Kim, Jin Woong; 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

  6. Laparoscopic Radiofrequency Ablation for Large Subcapsular Hepatic Hemangiomas: Technical and Clinical Outcomes

    PubMed Central

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

    2016-01-01

    Objectives The aim of this study was to evaluate the technical and clinical outcomes of using laparoscopic radiofrequency (RF) ablation for treating large subcapsular hepatic hemangiomas. Methods We retrospectively reviewed our sequential experience of treating 124 large subcapsular hepatic hemangiomas in 121 patients with laparoscopic RF ablation. Results The mean diameter of the 124 hemangiomas was 9.1 ± 3.2 cm (5.0–16.0 cm). RF ablation was performed successfully in all patients. There were 55 complications related to the ablation in 26 patients, including 5 of 69 (7.3%) patients with hemangioma <10 cm and 21 of 52 (40.4%) patients with hemangiomas ≥10 cm (P < 0.001). No injuries to abdominal viscera occurred in all the 121 patients. According to the Dindo–Clavien classification, all the complications were minor in 26 patients (Grade I). Out of 124 hepatic hemangiomas, 118 (95.2%) were completely ablated, including 70 of 72 (97.2%) lesions < 10 cm and 48 of 52 (92.3%) lesions ≥ 10 cm (P = 0.236). Conclusion Laparoscopic RF ablation therapy is a safe, feasible and effective procedure for large subcapsular hepatic hemangiomas, even in the hepatic hemangiomas ≥ 10 cm. Its use avoids thermal injury to the abdominal viscera. PMID:26901132

  7. 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.

  8. 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

  9. 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

  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. Navigated DENSE strain imaging for post-radiofrequency ablation lesion assessment in the swine left atria

    PubMed Central

    Schmidt, Ehud J.; Fung, Maggie M.; Ciris, Pelin Aksit; Song, Ting; Shankaranarayanan, Ajit; Holmvang, Godtfred; Gupta, Sandeep N.; Chaput, Miguel; Levine, Robert A.; Ruskin, Jeremy; Reddy, Vivek Y.; D'avila, Andre; Aletras, Anthony H.; Danik, Stephan B.

    2014-01-01

    Aims Prior work has demonstrated that magnetic resonance imaging (MRI) strain can separate necrotic/stunned myocardium from healthy myocardium in the left ventricle (LV). We surmised that high-resolution MRI strain, using navigator-echo-triggered DENSE, could differentiate radiofrequency ablated tissue around the pulmonary vein (PV) from tissue that had not been damaged by radiofrequency energy, similarly to navigated 3D myocardial delayed enhancement (3D-MDE). Methods and results A respiratory-navigated 2D-DENSE sequence was developed, providing strain encoding in two spatial directions with 1.2 × 1.0 × 4 mm3 resolution. It was tested in the LV of infarcted sheep. In four swine, incomplete circumferential lesions were created around the right superior pulmonary vein (RSPV) using ablation catheters, recorded with electro-anatomic mapping, and imaged 1 h later using atrial-diastolic DENSE and 3D-MDE at the left atrium/RSPV junction. DENSE detected ablation gaps (regions with >12% strain) in similar positions to 3D-MDE (2D cross-correlation 0.89 ± 0.05). Low-strain (<8%) areas were, on average, 33% larger than equivalent MDE regions, so they include both injured and necrotic regions. Optimal DENSE orientation was perpendicular to the PV trunk, with high shear strain in adjacent viable tissue appearing as a sensitive marker of ablation lesions. Conclusions Magnetic resonance imaging strain may be a non-contrast alternative to 3D-MDE in intra-procedural monitoring of atrial ablation lesions. PMID:24014803

  12. Spectroscopic investigation of volatile compounds produced during thermal and radiofrequency bipolar cautery on porcine liver

    NASA Astrophysics Data System (ADS)

    Rey, J. M.; Schramm, D.; Hahnloser, D.; Marinov, D.; Sigrist, M. W.

    2008-07-01

    The potential risks associated with the emission of by-products emitted by surgical cautery are of concern. Various investigations—mostly based on gas chromatography—have been performed to analyse the so-called surgical smoke but controversies remain in terms of composition and concentrations of compounds present in the smoke and hence the associated risk to human health. This quantitative model study uses for the first time CO2-laser-based photoacoustic spectroscopy and focuses on the analysis of volatile organic compounds produced during thermal- and radiofrequency bipolar cautery on porcine liver. The latter instrument is employed in actual human surgery. Concentrations in the ppm to sub-ppm range and molar fractions could be determined for carbon dioxide, water vapour, ammonia, ethanol and methanol. Distinct differences particularly in the methanol and ethanol contents were found between the two cautery devices employed.

  13. A bipolar radiofrequency, infrared, vacuum and mechanical massage device for treatment of cellulite: a pilot study.

    PubMed

    Hexsel, Doris M; Siega, Carolina; Schilling-Souza, Juliana; Porto, Manoela D; Rodrigues, Ticiana C

    2011-12-01

    Cellulite has a complex and multifactorial etiology. Synergistic action on treating cellulite has gained support in the treatment of cellulite. This study evaluated safety and efficacy of a bipolar radiofrequency, infrared, vacuum and mechanical massage device for cellulite treatment and reduction of body measures. This was a pilot study, which assessed 9 subjects who presented body mass index from 18 to 25 Kg/Kg and at least grade 6 in the Cellulite Severity Scale (CSS). All subjects underwent a 12-session treatment of posterior thighs and buttocks. There was a significant reduction of the hip circumference (p = 0.001), however, no changes in thigh circumferences were observed (p = 0.4). CSS has improved specifically on both buttocks [p = 0.002 (left side) and p = 0.038 (right side)], and no changes were observed on thighs. The studied device demonstrated efficacy in the reduction of cellulite severity and body circumference measures in the buttocks.

  14. 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

  15. 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

  16. 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

  17. 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.

  18. [Interventions on facet joints. Techniques of facet joint injection, medial branch block and radiofrequency ablation].

    PubMed

    Artner, J; Klessinger, S

    2015-10-01

    Fluoroscopy-guided interventions on facet joints have been used for decades for the symptomatic management of pain in spinal disorders. A large number of imaging techniques are used to achieve a precise and safe needle placement in interventional procedures. Pulsed fluoroscopy is one of the most widely used and well-accepted tools for these procedures. This article presents a technical overview of commonly used fluoroscopy-guided interventions on the facet joints of the cervical and lumbar spine, such as facet joint injection, blockade of the medial nerve branches and radiofrequency ablation.

  19. 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

  20. Electromagnetic tracking navigation to guide radiofrequency ablation of a lung tumor.

    PubMed

    Amalou, Hayet; Wood, Bradford J

    2012-10-01

    Radiofrequency ablation (RFA) may be an option for patients with lung tumors who have unresectable disease and are not suitable for available palliative modalities. RFA electrode positioning may take several attempts, necessitating multiple imaging acquisitions or continuous use of computed tomography. Electromagnetic tracking uses miniature sensors integrated with RFA equipment to guide tools in real time, while referencing to preprocedure imaging. This technology was demonstrated successfully during a lung tumor ablation, and this was more accurate at targeting the tumor compared with traditional freehand needle insertion. It is possible, although speculative and anecdotal, that more accuracy could prevent unnecessary repositioning punctures and decrease radiation exposure. Electromagnetic tracking has theoretical potential to benefit minimally invasive interventions.

  1. Teflon-buttressed sutures plus pericardium patch repair left ventricular rupture caused by radiofrequency catheter ablation

    PubMed Central

    Cao, Hao; Zhang, Qi; He, Yanzhong; Feng, Xiaodong; Liu, Zhongmin

    2016-01-01

    Abstract Background: Cardiac rupture often occurs after myocardial infarction or chest trauma with a high mortality rate. However, left ventricular rupture caused by radiofrequency catheter ablation (RFCA) is extremely rare. Methods: We describe a case of a 61-year-old male who survived from left ventricular rupture caused by a RFCA procedure for frequent ventricular premature contractions. Surgical exploration with cardiopulmonary bypass (CPB) was performed when the signs of cardiac tamponade developed 7 hours after the ablation surgery. Results: Teflon-buttressed sutures of the tear in the left ventricular posterolateral wall and pericardium patch applied to the contusion region on the wall repaired the rupture safely and effectively. Conclusion: Timely surgical intervention under CPB facilitated the survival of the patient. Teflon-buttressed sutures plus pericardium patch achieved the successful repair of the rupture. PMID:27661047

  2. 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

  3. 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

  4. Endoscopic ultrasound-guided radiofrequency ablation of the pancreas: An experimental study with pathological correlation

    PubMed Central

    Ungureanu, Bogdan Silviu; Pirici, Daniel; Mărgăritescu, Claudiu; Săndulescu, Larisa; Fronie, Simona; Pătraşcu, Ştefan; Şurlin, Valeriu; Săftoiu, Adrian

    2015-01-01

    Background: The treatment of pancreatic cancer represents a major objective in clinical research, as it still remains the fourth leading cause of cancer deaths among men and women, with approximately 6% of all cancer-related deaths. Materials and Methods: We studied the assessment of an endoscopic ultrasound (EUS)-guided radiofrequency ablation (RFA) probe through a 19G needle in order to achieve a desirable necrosis area in the pancreas. Radiofrequency ablation of the head of the pancreas was performed on 10 Yorkshire pigs with a weight between 25 kg and 35 kg and a length of 40-70 cm. Using an EUS-guided RFA experimental probe, we ablated an area of 2-3 cm width. The biological samples were harvested after 3 days and 5 days and necropsy was performed 1 week after the procedure. Results: All pigs showed no significant change regarding their behavior and no signs of complication was encountered. Blood analysis revealed increased values of amylase, alkaline phosphatase, and gamma-glutamyl transpeptidase on the 3rd day but a decrease on the 5th day. After necropsy and isolation of the pancreas, the ablated area was easily found, describing a solid necrosis. The pathological examination revealed a coagulative necrosis area with minimal invasion and inflammatory tissue at about 2 cm surrounding the lesion. Conclusion: EUS-RFA is a feasible technique and might represent a promising therapy for the future treatment of pancreatic cancer. However, further studies are necessary to investigate EUS-guided RFA as an option for palliation in pancreatic cancer until it can be successfully used in human patients. PMID:26643702

  5. 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

  6. 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.

  7. Therapeutic efficacy comparison of radiofrequency ablation in hepatocellular carcinoma and metastatic liver cancer

    PubMed Central

    LIU, JING; QIAN, LIN-XUE

    2014-01-01

    The aim of this study was to evaluate the effect of radiofrequency ablation (RFA) on malignant hepatic tumors and compare its therapeutic efficacy in hepatocellular carcinoma (HCC) and metastatic liver cancer (MLC). A total of 56 patients with malignant hepatic tumors (34 patients with HCC and 22 patients with MLC) underwent RFA treatment. Two weeks following the RFA treatment, contrast-enhanced abdominal computed tomography scans were used to investigate whether the ablation of the tumors was complete. The patients were followed up for a period ranging from 1 to 93 months, to compare recurrence rates, distant recurrence rates and survival rates. The HCC group exhibited an initial complete ablation rate of 94.1% compared with 95.4% for the MLC group; the difference in ablation rates was not identified to be statistically significant. The recurrence and distant recurrence rates were 14.7% and 11.8%, respectively, for the HCC group and 9.1% and 36.4%, respectively, for the MLC group. The 1-, 3- and 5-year survival rates of the patients with HCC were 86.2, 71.4 and 60.0%, respectively, whereas those for the patients with MLC were 73.9%, 45.4% and 37.5%, respectively. The survival rates of the two groups were identified to be significantly different (P=0.002). RFA treatment was therefore shown to be effective in treating small (<5 cm) malignancies, which is clinically significant. PMID:24669247

  8. Radiofrequency Ablation of Lung Tumors: Imaging Features of the Postablation Zone

    PubMed Central

    Eradat, Jilbert; Gutierrez, Antonio J.; Lee, Christopher; Fishbein, Michael C.; Suh, Robert D.

    2012-01-01

    Radiofrequency ablation (RFA) is used to treat pulmonary malignancies. Although preliminary results are suggestive of a survival benefit, local progression rates are appreciable. Because a patient can undergo repeat treatment if recurrence is detected early, reliable post-RFA imaging follow-up is critical. The purpose of this article is to describe (a) an algorithm for post-RFA imaging surveillance; (b) the computed tomographic (CT) appearance, size, enhancement, and positron emission tomographic (PET) metabolic activity of the ablation zone; and (c) CT, PET, and dual-modality imaging with PET and CT (PET/CT) features suggestive of partial ablation or tumor recurrence and progression. CT is routinely used for post-RFA follow-up. PET and PET/CT have emerged as auxiliary follow-up techniques. CT with nodule densitometry may be used to supplement standard CT. Post-RFA follow-up was divided into three phases: early (immediately after to 1 week after RFA), intermediate (>1 week to 2 months), and late (>2 months). CT and PET imaging features suggestive of residual or recurrent disease include (a) increasing contrast material uptake in the ablation zone (>180 seconds on dynamic images), nodular enhancement measuring more than 10 mm, any central enhancement greater than 15 HU, and enhancement greater than baseline anytime after ablation; (b) growth of the RFA zone after 3 months (compared with baseline) and definitely after 6 months, peripheral nodular growth and change from ground-glass opacity to solid opacity, regional or distant lymph node enlargement, and new intrathoracic or extrathoracic disease; and (c) increased metabolic activity beyond 2 months, residual activity centrally or at the ablated tumor, and development of nodular activity. © RSNA, 2012 PMID:22786987

  9. 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

  10. Prediction of Primary Slow-Pathway Ablation Success Rate according to the Characteristics of Junctional Rhythm Developed during the Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia

    PubMed Central

    Bagherzadeh, Ataallah; Rezaee, Mohammad Esmaeel; Farahani, Maryam Moshkani

    2011-01-01

    Background Nowadays, developed junctional rhythm (JR) that occurs during slow-pathway radiofrequency (RF) catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT) has been focused upon as a highly sensitive surrogate end point for successful radiofrequency ablation. This study was conducted to assess the relationship between the presence and pattern of developed JR during the RF ablation of AVNRT and a successful outcome. Methods Seventy-five patients aged between 14 and 88 who underwent slow-pathway RF ablation due to symptomatic AVNRT were enrolled into the study and received a total of 162 RF energy applications. Combined anatomic and electrogram mapping approach was used for slow-pathway RF ablation. The ablation procedure consisted of 60-second, 60 °C temperature-controlled energy delivery. After each ablation pulse, successful ablation was assessed according to the loss of AVNRT inducibility via isoproterenol infusion. Four different patterns were considered for the developed JR, namely sparse, intermittent, continuous, and transient block. Success ablation rate was assessed with respect to the position, pattern, and number of junctional beats. Results Successful RF ablation with a loss of AVNRT inducibility was achieved in 43 (57.3%) patients using 119 RF energy applications (73.5%). JR developed in 133 of the 162 (82.1%) applications with a given sensitivity of 90.8% and low specificity of 41.9% as an end point of successful RF ablation, with a negative predictive value of 62.1%. The mean number of the developed junctional beats was significantly higher in the successful ablations (p value < 0.001), and the ROC analysis revealed that the best cut-off point of the cumulative junctional beats for identifying accurate AVNRT ablation therapy is 14 beats with 90.76 % sensitivity and 90.70% specificity. There were no significant differences in terms of successful ablation rates according to the four different patterns of JR and its positions (p

  11. Radiofrequency Thermal Ablation: Increase in Lesion Diameter with Continuous Acetic Acid Infusion

    SciTech Connect

    Lubienski, Andreas Duex, Markus; Lubienski, Katrin; Grenacher, Lars; Kauffmann, Guenter

    2005-12-15

    Purpose. To evaluate the influence of continuous infusion of acetic acid 50% during radiofrequency ablation (RFA) on the size of the thermal lesion produced. Methods. Radiofrequency (RF) was applied to excised bovine liver by using an expandable needle electrode with 10 retractable tines (LeVeen Needle Electrode, RadioTherapeutics, Sunnyvale, CA) connected to a commercially available RF generator (RF 2000, RadioTherapeutics, Sunnyvale, CA). Experiments were performed using three different treatment modalities: RF only (n = 15), RF with continuous saline 0.9% infusion (n = 15), and RF with continuous acetic acid 50% infusion (n = 15). RF duration, power output, tissue impedance, and time to a rapid rise in impedance were recorded. The ablated lesions were evaluated both macroscopically and histologically. Results. The ablated lesions appeared as spherical or ellipsoid, well-demarcated pale areas with a surrounding brown rim with both RF only and RF plus saline 0.9% infusion. In contrast, thermolesions generated with RF in combination with acetic acid 50% infusion were irregular in shape and the central portion was jelly-like. Mean diameter of the coagulation necrosis was 22.3 {+-} 2.1 mm (RF only), 29.2 {+-} 4.8 mm (RF + saline 0.9%) and 30.7 {+-} 5.7 mm (RF + acetic acid 50%), with a significant increase in the RF plus saline 0.9% and RF plus acetic acid 50% groups compared with RF alone. Time to a rapid rise in impedance was significantly prolonged in the RF plus saline 0.9% and RF plus acetic acid 50% groups compared with RF alone. Conclusions. A combination of RF plus acetic acid 50% infusion is able to generate larger thermolesions than RF only or RF combined with saline 0.9% infusion.

  12. 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

  13. Radiofrequency catheter ablation of intractable ventricular tachycardia in an infant following arterial switch operation.

    PubMed

    Costello, John P; He, Dingchao; Greene, Elizabeth A; Berul, Charles I; Moak, Jeffrey P; Nath, Dilip S

    2014-01-01

    A full-term male neonate presented with cyanosis upon delivery and was subsequently diagnosed with d-transposition of the great arteries, ventricular septal defect, and restrictive atrial septal defect. Following initiation of intravenous prostaglandins and balloon atrial septostomy, an arterial switch operation was performed on day 3 of life. The postoperative course was complicated by intractable ventricular tachycardia that was refractory to lidocaine, amiodarone, esmolol, fosphenytoin, and mexiletine drug therapy. Ventricular tachycardia was suppressed with overdrive atrial pacing but recurred upon discontinuation. Seven weeks postoperatively, radiofrequency catheter ablation was performed due to hemodynamically compromising persistent ventricular tachycardia refractory to medical therapy. The ventricular tachycardia was localized to the inferior-lateral right ventricular outlet septum. The procedure was successful without complications or recurrence. Antiarrhythmics were discontinued after the ablation procedure. Seven days after the ablation, a different, slower fascicular rhythm was noted to compete with the infant's sinus rhythm. This was consistent with the preablation amiodarone having reached subtherapeutic levels given its very long half-life. The patient was restarted on oral beta blockers and amiodarone. The patient was subsequently discharged home in predominantly sinus rhythm with intermittent fascicular rhythm. PMID:23647934

  14. Risk of Ionizing Radiation in Women of Childbearing Age undergoing Radiofrequency Ablation

    PubMed Central

    de Lima, Gustavo Glotz; Gomes, Daniel Garcia; Gensas, Caroline Saltz; Simão, Mariana Fernandez; Rios, Matheus N.; Pires, Leonardo Martins; Kruse, Marcelo Lapa; Leiria, Tiago Luiz Luz

    2013-01-01

    Background The International Commission of Radiology recommends a pregnancy screening test to all female patients of childbearing age who will undergo a radiological study. Radiation is known to be teratogenic and its effect is cumulative. The teratogenic potential starts at doses close to those used during these procedures. The prevalence of positive pregnancy tests in patients undergoing electrophysiological studies and/or catheter ablation in our midst is unknown. Objective To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation. Methods Cross-sectional study analyzing 2,966 patients undergoing electrophysiological study and/or catheter ablation, from June 1997 to February 2013, in the Institute of Cardiology of Rio Grande do Sul. A total of 1490 procedures were performed in women, of whom 769 were of childbearing age. All patients were screened with a pregnancy test on the day before the procedure. Results Three patients tested positive, and were therefore unable to undergo the procedure. The prevalence observed was 3.9 cases per 1,000 women of childbearing age. Conclusion Because of their safety and low cost, pregnancy screening tests are indicated for all women of childbearing age undergoing radiological studies, since the degree of ionizing radiation needed for these procedures is very close to the threshold for teratogenicity, especially in the first trimester, when the signs of pregnancy are not evident. PMID:24061686

  15. Chemotherapy plus percutaneous radiofrequency ablation in patients with inoperable colorectal liver metastases

    PubMed Central

    Sgouros, Joseph; Cast, James; Garadi, Krishna K; Belechri, Maria; Breen, David J; Monson, John RT; Maraveyas, Anthony

    2011-01-01

    AIM: To access the efficacy of chemotherapy plus radiofrequency ablation (RFA) as one line of treatment in inoperable colorectal liver metastases. METHODS: Eligible patients were included in three Phase II studies. In the first study percutaneous RFA was used first followed by 6 cycles of 5-fluorouracil, leucovorin and irinotecan combination (FOLFIRI) (adjunctive chemotherapy trial). In the other two, chemotherapy (FOLFIRI or 5-fluorouracil, leucovorin and oxaliplatin combination) up to 12 cycles was used first with percutaneous RFA offered to responding patients (primary chemotherapy trials). RESULTS: Thirteen patients were included in the adjunctive chemotherapy trial and 17 in the other two. At inclusion they had 1-4 liver metastases (up to 6.5 cm in size). Two patients died during chemotherapy. All patients in the adjunctive chemotherapy trial and 44% in the primary chemotherapy studies had their metastases ablated. Median PFS and overall survival in the adjunctive study were 13 and 24 mo respectively while in the primary chemotherapy studies they were 10 and 21 mo respectively. Eighty one percent of the patients had tumour relapse in at least one previously ablated lesion. CONCLUSION: Chemotherapy plus RFA in patients with low volume inoperable colorectal liver metastases seems safe and relatively effective. The high local recurrence rate is of concern. PMID:21528091

  16. Laparoscopic Habib™ 4X: a bipolar radiofrequency device for bloodless laparoscopic liver resection

    PubMed Central

    Pai, M.; Navarra, G.; Ayav, A.; Sommerville, C.; Khorsandi, S. K.; Damrah, O.; Jiao, L. R.

    2008-01-01

    Background. In recent years the progress of laparoscopic procedures and the development of new and dedicated technologies have made laproscopic hepatic surgery feasible and safe. In spite of this laparoscopic liver resection remains a surgical procedure of great challenge because of the risk of massive bleeding during liver transection and the complicated biliary and vascular anatomy in the liver. A new laparoscopic device is reported here to assist liver resection laparoscopically. Methods. The laparoscopic Habib™ 4X is a bipolar radiofrequency device consisting of a 2x2 array of needles arranged in a rectangle. It is introduced perpendicularly into the liver, along the intended transection line. It produces coagulative necrosis of the liver parenchyma sealing biliary radicals and blood vessels and enables bloodless transection of the liver parenchyma. Results. Twenty-four Laparoscopic liver resections were performed with LH4X out of a total of 28 attempted resections over 12 months. Pringle manoeuvre was not used in any of the patients. None of the patients required intraoperative transfusion of red cells or blood products. Conclusion. Laparoscopic liver resection can be safely performed with laparoscopic Habib™ 4X with a significantly low risk of intraoperative bleeding or postoperative complications. PMID:18773100

  17. Percutaneous Image-guided Radiofrequency Ablation of Tumors in Inoperable Patients - Immediate Complications and Overall Safety

    PubMed Central

    Sahay, Anubha; Sahay, Nishant; Kapoor, Ashok; Kapoor, Jyoti; Chatterjee, Abhishek

    2016-01-01

    Introduction: Percutaneous destruction of cancer cells using a radiofrequency energy source has become an accepted part of the modern armamentarium for managing malignancies. Radiofrequency ablation (RFA) is a relatively novel procedure for treating recurrent and metastatic tumors. It is used for debulking tumors and as adjuvant therapy for palliative care apart from its role as a pain management tool. Its use in the third world countries is limited by various factors such as cost and expertise. In the remotest parts of India, where economic development has been slow, abject poverty with poor health care facilities advanced malignancies present a challenge to health care providers. We undertook this study to assess the safety of the percutaneous RFA tumor ablation as a therapeutic or palliative measure in patients where surgery was not possible. We observed that RFA may be an effective, alternative therapeutic modality for some inoperable tumors where other therapeutic modalities cannot be considered. Context: Palliative and therapeutic image-guided RFAs of tumors may be the only treatment option in patients who are inoperable for a variety of reasons. To assess the safety and complications of RFA in such a patient population is important before embarking upon any interventions given their physically, mentally, and socially compromised status in a country such as India. Aims: To assess the safety of percutaneous image-guided radiofrequency tumor ablation and to note the various immediate and early complications of the intervention. Settings and Design: This was a prospective, observational study conducted in Tata Main Hospital, Jamshedpur, Jharkhand, India. Subjects and Methods: After approval by the Hospital Approval Committee all patients who consented for percutaneous RFA of their tumor admitted in the hospital were included after taking fully informed consent from patient/close relative keeping the following criteria in view. Inclusion Criteria: Patients who

  18. Intracardiac echocardiography to guide transseptal catheterization for radiofrequency catheter ablation of left-sided accessory pathways: two case reports.

    PubMed

    Citro, Rodolfo; Ducceschi, Valentino; Salustri, Alessandro; Santoro, Michele; Salierno, Michele; Gregorio, Giovanni

    2004-10-08

    Intracardiac echocardiography (ICE) is a useful tool for guiding transseptal puncture during electrophysiological mapping and ablation procedures. Left-sided accessory pathways (LSAP) can be ablated by using two different modalities: retrograde approach through the aortic valve and transseptal approach with puncture of the fossa ovalis. We shall report two cases of LSAP where transcatheter radiofrequency ablation (TCRFA) was firstly attempted via transaortic approach with ineffective results. Subsequently, a transseptal approach under ICE guidance has been performed. During atrial septal puncture ICE was able to locate the needle tip position precisely and provided a clear visualization of the "tenting effect" on the fossa ovalis. ICE allowed a better mapping of the mitral ring and a more effective catheter ablation manipulation and tip contact which resulted in a persistent and complete ablation of the accessory pathway with a shorter time of fluoroscopic exposure. ICE-guided transseptal approach might be a promising modality for TCRFA of LSAP.

  19. Atrial conduction delay predicts atrial fibrillation in paroxysmal supraventricular tachycardia patients after radiofrequency catheter ablation.

    PubMed

    Xu, Zhen-Xing; Zhong, Jing-Quan; Zhang, Wei; Yue, Xin; Rong, Bing; Zhu, Qing; Zheng, Zhaotong; Zhang, Yun

    2014-06-01

    This study aimed to assess whether intra- and inter-atrial conduction delay could predict atrial fibrillation (AF) for paroxysmal supraventricular tachycardia (PSVT) patients after successful treatment by radiofrequency catheter ablation (RFCA). Echocardiography examination was performed on 524 consecutive PSVT patients (15 patients were excluded). Left atrial dimension, right atrial diameter and intra- and inter-atrial conduction delay were measured before ablation. Patients were divided into group A (n = 32): occurrence of AF after the ablation and group B (n = 477): remained in sinus rhythm during follow-up. Receiver operating characteristic (ROC) curve analysis was performed to estimate the predictive value of intra- and inter-atrial conduction delay. Both intra- and inter-atrial conduction delay were higher in group A than in group B (4.79 ± 0.30 msec vs. 4.56 ± 0.32 msec; 21.98 ± 1.32 msec vs. 20.01 ± 1.33; p < 0.05). Binary logistic regression analysis showed that intra- and inter-atrial conduction were significant influential factors for the occurrence of AF (odds ratio [OR] = 13.577, 95% confidence interval [CI], 3.469-48.914; OR = 2.569, 95% CI, 1.909-3.459, p < 0.05). The ROC cure analysis revealed that intra-atrial conduction delay ≥ 4.45 msec and inter-atrial conduction delay ≥ 20.65 were the most optimal cut-off value for predicting AF in PSVT patients after RFCA. In conclusion, this is the first study to show that the intra- and inter-atrial conduction delay could effectively predict AF in post-ablation PSVT patients.

  20. Endoscopic 3D-OCT reveals buried glands following radiofrequency ablation of Barrett's esophagus

    NASA Astrophysics Data System (ADS)

    Zhou, Chao; Adler, Desmond C.; Tsai, Tsung-Han; Lee, Hsiang-Chieh; Becker, Lauren; Schmitt, Joseph M.; Huang, Qin; Fujimoto, James G.; Mashimo, Hiroshi

    2010-02-01

    Barrett's esophagus (BE) with high-grade dysplasia is generally treated by endoscopic mucosal resection or esophagectomy. Radiofrequency ablation (RFA) is a recent treatment that allows broad and superficial ablation for BE. Endoscopic three-dimensional optical coherence tomography (3D-OCT) is a volumetric imaging technique that is uniquely suited for follow-up surveillance of RFA treatment. 3D-OCT uses a thin fiberoptic imaging catheter placed down the working channel of a conventional endoscope. 3D-OCT enables en face and cross-sectional evaluation of the esophagus for detection of residual BE, neo-squamous mucosa, or buried BE glands. Patients who had undergone RFA treatment with the BARRX HALO90 system were recruited and imaged with endoscopic 3D-OCT before and after (3-25 months) RFA treatment. 3D-OCT findings were compared to pinch biopsy to confirm the presence or absence of squamous epithelium or buried BE glands following RFA. Gastric, BE, and squamous epithelium were readily distinguished from 3D-OCT over a large volumetric field of view (8mmx20mmx1.6 mm) with ~5μm axial resolution. In all patients, neosquamous epithelium (NSE) was observed in regions previously treated with RFA. A small number of isolated glands were found buried beneath the regenerated NSE and lamina propria. NSE is a marker of successful ablative therapy, while buried glands may have malignant potential and are difficult to detect using conventional video endoscopy and random biopsy. Buried glands were not observed with pinch biopsy due to their extremely sparse distribution. These results indicate a potential benefit of endoscopic 3D-OCT for follow-up assessment of ablative treatments for BE.

  1. 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.

  2. Radiofrequency ablation of hepatic tumors: simulation, planning, and contribution of virtual reality and haptics.

    PubMed

    Villard, Caroline; Soler, Luc; Gangi, Afshin

    2005-08-01

    For radiofrequency ablation (RFA) of liver tumors, evaluation of vascular architecture, post-RFA 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, treatment planning, and training tool, that simulates the insertion of the needle, the necrosis of the treated area, and proposes an optimal needle placement, has been developed. The 3D scenes are automatically reconstructed from enhanced spiral CT scans. The simulator takes into account the cooling effect of local vessels greater than 3 mm in diameter, making necrosis shapes more realistic. Optimal needle positioning can be automatically generated by the software to produce complete destruction of the tumor, with maximum respect of the healthy liver and of all major structures to avoid. We also studied how the use of virtual reality and haptic devices are valuable to make simulation and training realistic and effective. PMID:16298844

  3. Case Report of Autopsy and Placental Examination After Radiofrequency Ablation of an Acardiac Twin.

    PubMed

    Kashireddy, Papreddy; Larson, Alexandra; Minturn, Lucy; Ernst, Linda

    2015-01-01

    We report the autopsy and placental findings in a monochorionic twin gestation complicated by twin reversed arterial perfusion (TRAP) sequence. Radiofrequency ablation (RFA) was performed at 24 weeks gestation to abort the acardiac fetus, and vaginal delivery of the co-twin and acardiac fetus occurred at 33 weeks gestation. An autopsy of the acardiac fetus revealed multiple congenital anomalies including complete absence of the upper extremities and poor development of the skull and facial structures. In contrast to the upper body, the lower half of the body, although malformed, was more developed. The monochorionic twin placenta showed velamentous, atrophied, proximal artery-artery and vein-vein intertwin vascular connections which essentially bypassed the placental parenchyma for the acardiac fetus. Ink injection and histologic examination confirmed thrombosis of these critical intertwin vascular connections after RFA. This report highlights the fetal and placental anatomy of TRAP sequence and stresses the importance of placental examination after fetal surgical techniques. PMID:26199267

  4. 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

  5. Inflammatory Myofibroblastic Tumor: a Possible Complication of Percutaneous Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Lee, Su Hyun; Lee, Jae Young; Kim, Soo Jin; Kim, Min A; Han, Joon Koo; Choi, Byung Ihn

    2009-01-01

    An inflammatory myofibroblastic tumor (IMT) is an uncommon, benign lesion characterized by the mesenchymal proliferation and infiltration of inflammatory cells composed primarily of lymphocytes and plasma cells. A percutaneous radiofrequency ablation (RFA) is an effective and safe therapeutic modality used for the management of liver malignancies. Here we report, for the first time, a case of IMT as a complication of RFA for hepatocellular carcinoma in a 61-year-old man with a Child's class A hepatitis B-related liver cirrhosis. Gastrohepatic fistula formation was pathologically proven and associated with the RFA. Such a longstanding inflammation of the fistula might have been a possible cause of the development of IMT in this case. PMID:19885321

  6. 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.

  7. Radiofrequency Ablation to Treat Loco-Regional Recurrence of Well-Differentiated Thyroid Carcinoma

    PubMed Central

    Lee, Sun Jin; Kim, Bum Soo; Ahn, Kook Jin; Choi, Hyun Seok; Lim, Dong Jun; Kim, Min Hee; Bae, Ja Seong; Kim, Min Sik; Jung, Chan Kwon; Chong, Se Min

    2014-01-01

    Objective To evaluate the efficacy of radiofrequency ablation (RFA) in the treatment of loco-regional, recurrent, and well-differentiated thyroid carcinoma. Materials and Methods Thirty-five recurrent well-differentiated thyroid carcinomas (RTC) in 32 patients were treated with RFA, between March 2008 and October 2011. RTCs were detected by regular follow-up ultrasound and confirmed by biopsy. All patients had fewer than 3 RTCs in the neck and were at high surgical risk or refused to undergo repeated surgery. Average number of RFA sessions were 1.3 (range 1-3). Post-RFA biopsy and ultrasound were performed. The mean follow-up period was 30 months. Pre- and post-RFA serum thyroglobulin values were evaluated. Results Thirty-one patients with 33 RTCs were treated with RFA only, whereas 1 patient with 2 RTCs was treated with RFA followed by surgery. At the last follow-up ultrasound, 31 (94%) of the 33 RTCs treated with RFA alone completely disappeared and the remaining 2 (6%) RTCs showed decreased volume. The largest diameter and volume of the 33 RTCs were markedly decreased by 93.2% (from 8.1 ± 3.4 mm to 0.6 ± 1.8 mm, p < 0.001) and 96.4% (from 173.9 ± 198.7 mm3 to 6.2 ± 27.9 mm3, p < 0.001), respectively. Twenty of the 21 RTCs evaluated with post-RFA biopsies (95%) were negative for malignancy. One (5%) showed remaining tumor that was removed surgically. The serum thyroglobulin was decreased in 19 of 26 patients (73%). Voice change developed immediately after RFA in 6 patients (19%) and was spontaneously recovered in 5 patients (83%). Conclusion Radiofrequency ablation can be effective in treating loco-regional, recurrent, and well-differentiated thyroid carcinoma in patients at high surgical risk. PMID:25469095

  8. 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

  9. 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

  10. 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

  11. 27.12 MHz Radiofrequency Ablation for Benign Cutaneous Lesions.

    PubMed

    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

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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.

  17. A novel four-wire-driven robotic catheter for radio-frequency ablation treatment

    PubMed Central

    Kato, Takahisa; Song, Sang-Eun; Hata, Nobuhiko

    2014-01-01

    Purpose Robotic catheters have been proposed to increase the efficacy and safety of the radio-frequency ablation treatment. The robotized motion of current robotic catheters mimics the motion of manual ones—namely, deflection in one direction and rotation around the catheter. With the expectation that the higher dexterity may achieve further efficacy and safety of the robotically driven treatment, we prototyped a four-wire-driven robotic catheter with the ability to deflect in two- degree-of-freedom motions in addition to rotation. Methods A novel quad-directional structure with two wires was designed and developed to attain yaw and pitch motion in the robotic catheter. We performed a mechanical evaluation of the bendability and maneuverability of the robotic catheter and compared it with current manual catheters. Results We found that the four-wire-driven robotic catheter can achieve a pitching angle of 184.7° at a pulling distance of wire for 11mm, while the yawing angle was 170.4° at 11mm. The robotic catheter could attain the simultaneous two- degree-of-freedom motions in a simulated cardiac chamber. Conclusion The results indicate that the four-wire-driven robotic catheter may offer physicians the opportunity to intuitively control a catheter and smoothly approach the focus position that they aim to ablate. PMID:24510205

  18. Volumeteric treatment planning and image guidance for radiofrequency ablation of hepatic tumors

    NASA Astrophysics Data System (ADS)

    Cleary, Kevin R.; Tanaka, Daigo; Stewart, David; Wood, Bradford J.; Mocanu, Mihai L.; Levy, Elliot; Banovac, Filip; Lindisch, David; Roderick, Stephen; Tang, John; Chung, Ho Young

    2003-05-01

    This paper describes a computer program for volumetric treatment planning and image guidance during radiofrequency (RF) ablation of hepatic tumors. The procedure is performed by inserting an RF probe into the tumor under image guidance and generating heat to 'cook' a spherical region. If the tumor is too large to be ablated in a single burn, then multiple overlapping spherical burns are needed to encompass the entire target area. The computer program is designed to assist the physician in planning the sphere placement, as well as provide guidance in placing the probe using a magnetic tracking device. A pre-operative CT scan is routinely obtained before the procedure. On a slice by slice basis, the tumor, along with a 1 cm margin, is traced by the physician using the computer mouse. Once all of the images are traced, the program provides a three-dimensional rendering of the tumor. The minimum number of spheres necessary to cover the target lesion and the 1 cm margin are then computed by the program and displayed on the screen.

  19. 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

  20. Laparoscopic Radiofrequency Thermal Ablation of Hepatocellular Carcinoma in Liver Cirrhosis Patients

    PubMed Central

    Seleem, Mohamed Ismail; Gerges, Shawkat Shaker; Elkhouly, Ashrif; El-wakeel, Bahaa; Hassany, Mohamed

    2012-01-01

    Background Laparoscopic radiofrequency ablation (LRFA) for hepatocellular carcinoma (HCC) under guidance of intra-operative laparoscopic ultrasound (IOLUS) aiming of obtaining additional information for liver situation, better tumor staging and effective treatment of hepatic focal lesion (HFL) in patients with a difficult percutaneous approach. Methods Between September 2010 and July 2012, 301 patients with HCC in liver cirrhosis were referred from HCC clinic at National Hepatology and Tropical Medicine Research Institute (NHTMRI). Twenty nine patients were submitted to LRFA with IOLUS guidance. Operation time, hospital stay, post procedure complication were recorded. Spiral CT scan one month postoperative was mandatory during follow up. Results LRFA was completed in all patients. The IOLUS examination identified new HFL in three patients. A total of 32 lesions were treated. The mean operative time was 120 minutes; eight procedures were associated in six patients: cholecystectomy (6) and adhesiolysis (2). A complete tumor ablation was observed in all patients which were documented via spiral computed tomography (CT scan) one month after treatment. Conclusion LRFA of HCC proved to be a safe and effective technique. IOLUS is superior on spiral CT scan in detection a small HCC.

  1. 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

  2. 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.

  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. 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.

  5. Insufficient Radiofrequency Ablation Promotes Angiogenesis of Residual Hepatocellular Carcinoma via HIF-1α/VEGFA

    PubMed Central

    Pan, Bing; Ke, Shan; Dong, Shuying; Li, Xiuli; Zhou, Aimin; Zheng, Lemin; Sun, Wen-bing

    2012-01-01

    Background The mechanism of rapid growth of the residual tumor after radiofrequency (RF) ablation is poorly understood. In this study, we investigated the effect of hyperthermia on HepG2 cells and generated a subline with enhanced viability and dys-regulated angiogenesis in vivo, which was used as a model to further determine the molecular mechanism of the rapid growth of residual HCC after RF ablation. Methodology/Principal Findings Heat treatment was used to establish sublines of HepG2 cells. A subline (HepG2 k) with a relatively higher viability and significant heat tolerance was selected. The cellular protein levels of VEGFA, HIF-1α and p-Akt, VEGFA mRNA and secreted VEGFA were measured, and all of these were up-regulated in this subline compared to parental HepG2 cells. HIF-1α inhibitor YC-1 and VEGFA siRNA inhibited the high viability of the subline. The conditioned media from the subline exerted stronger pro-angiogenic effects. Bevacizumab, VEGFA siRNA and YC-1 inhibited proangiogenic effects of the conditioned media of HepG2 k cells and abolished the difference between parental HepG2 cells and HepG2 k cells. For in vivo studies, a nude mouse model was used, and the efficacy of bavacizumab was determined. HepG2 k tumor had stronger pro-angiogenic effects than parental HepG2 tumor. Bevacizumab could inhibit the tumor growth and angiogenesis, and also eliminate the difference in tumor growth and angiogenesis between parental HepG2 tumor and HepG2 k tumor in vivo. Conclusions/Significance The angiogenesis induced by HIF1α/VEGFA produced by altered cells after hyperthermia treatment may play an important role in the rapid growth of residual HCC after RF ablation. Bevacizumab may be a good candidate drug for preventing and treating the process. PMID:22615958

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. Recurrent intra-articular osteoid osteoma of the hip after radiofrequency ablation: a case report and review of the literature

    PubMed Central

    Efstathopoulos, Nicolas; Sapkas, Georgios; Xypnitos, Fragiskos N; Lazarettos, Ioannis; Korres, Demetrios

    2009-01-01

    We present a case of a 53-year-old woman with recurrent intra-articular osteoid osteoma of the hip 6 months after initial treatment with percutaneous radiofrequency ablation. En bloc surgical excision of the osteoid osteoma and prophylactic internal fixation for impending stress fracture was performed. The patient is pain free, has returned to normal function and there is no sign of recurrence at the one-year follow-up. Intraarticular osteoid osteoma, present a diagnostic challenge and often they are misdiagnosed. Minimally invasive ablation techniques can fail in significant percentage and then surgical excision with histological confirmation remains the definitive treatment of choice. PMID:19829804

  15. 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.

  16. 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.

  17. 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

  18. Adjuvant liposomal doxorubicin markedly affects radiofrequency (RF) ablation-induced effects on periablational microvasculature

    PubMed Central

    Moussa, Marwan; Goldberg, S. Nahum; Tasawwar, Beenish; Sawant, Rupa R.; Levchenko, Tatyana; Kumar, Gaurav; Torchilin, Vladimir P.; Ahmed, Muneeb

    2013-01-01

    Purpose To evaluate the effects of radiofrequency (RF) ablation without and with adjuvant IV liposomal doxorubicin (Doxil®) on microvessel morphology and patency and intratumoral drug delivery and retention. Materials and Methods A total of 133 tumors/animals were used. First, single subcutaneous tumors (R3230 in Fischer rats, and 786-0 in nude mice) were randomized to receive RF alone or no treatment, and sacrificed 0-72hr post-treatment. Next, combined RF/liposomal doxorubicin (1mg given 15min post-RF) was studied in R3230 tumors at 0-72hr post-treatment. Histopathologic assessment including immunohistochemical staining for ced caspase-3), heat shock protein 70 and CD34 were performed to assess morphologic vessel appearance, vessel diameter, and microvascular density. Subsequently, animals were randomized to receive RF alone, RF/liposomal doxorubicin, or control tumors, followed by intravenous fluorescent-labeled liposomes (a surrogate marker) given 0-24hr post-RF to permit qualitative assessment. Results RF ablation alone results in enlarged and dysmorphic vessels from 0-4hr, peaking at 12-24hr post-RF, occurring preferentially closer to the electrode. The addition of doxorubicin resulted in earlier vessel contraction (mean vessel area 47539±9544μm² vs. 1854±458μm² for RF alone at 15min, p<0.05). Combined RF/liposomal doxorubicin produced similar fluorescence 1hr post-treatment (40.88±33.53 AU/μm² vs. 22.1±13.19 AU/μm², p=0.14), but significantly less fluorescence at 4hr (24.3±3.65 AU/μm² vs. 2.8 ±3.14 AU/μm², p<0.002) compared to RF alone denoting earlier reduction in microvascular patency. Conclusion RF ablation induces morphologic changes to vessels within the ablation zone lasting up to 12-24hr post-treatment. The addition liposomal doxorubicin causes early vessel contraction and a reduction in periablational microvascular patency. Such changes will likely need to be considered when determining optimal drug administration and imaging

  19. 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

  20. Treatment efficacy of radiofrequency ablation of 338 patients with hepatic malignant tumor and the relevant complications

    PubMed Central

    Chen, Min-Hua; Yang, Wei; Yan, Kun; Gao, Wen; Dai, Ying; Wang, Yan-Bin; Zhang, Xiao-Peng; Yin, Shan-Shan

    2005-01-01

    AIM: To investigate the treatment efficacy of radiofrequency ablation (RFA) of hepatic malignant tumor and the relevant complications. METHODS: A total of 338 patients with 763 hepatic tumors underwent ultrasound-guided RFA (565 procedures). There were 204 cases of hepatic cellular carcinoma (HCC) with 430 tumors, the mean largest diameter was 4.0 cm. Of them, 48 patients (23.5%) were in stages I-II (UICC Systems) and 156 (76.5%) in stages III-IV There were 134 cases of metastatic liver carcinoma (MLC), with 333 metastases in the liver, the mean diameter was 4.1 cm, the liver metastases of 96 patients (71.6%) came from gastrointestinal tract. Ninety-three percent of the 338 patients were treated using the relatively standard protocol. Crucial attention must be paid to monitor the abnormal changes in ultrasound images as well as the vital signs of the patients to find the possible hemorrhage and peripheral structures injury in time. The tumors were considered as ablated completely, if no viability was found on enhanced CT within 24 h or at 1 mo after RFA. These patients were followed up for 3-57 mo. RESULTS: The ablation success rate was 93.3% (401/430 tumors) for HCC and was 96.7% (322/333 tumors) for MLC. The local recurrence rate for HCC and MLC was 7.9% (34/430 tumors) and 10.5% (35/333 tumors), respectively. A total of 137 patients (40.5%) underwent 2-11 times of repeated ablations because of tumor recurrence or metastasis. The 1st, 2nd, and 3rd year survival rate was 84.6%, 66.6%, and 63.1%, respectively; the survival rate from 48 patients of I-II stage HCC was 93.7%, 80.4%, and 80.4%, respectively. The major complication rate in this study was 2.5% (14 of 565 procedures), which consisted of 5 hemorrhages, 1 colon perforation, 5 injuries of adjacent structures, 2 bile leakages, and 1 skin burn. CONCLUSION: RFA, as a minimally invasive local treatment, has become an effective and relatively safe alternative for the patients of hepatic malignant tumor, even of

  1. 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

  2. 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

  3. Temperature-controlled cooled-tip radiofrequency linear ablation of the atria guided by a realtime position management system.

    PubMed

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

    2011-01-01

    Due to the difficulty in producing a transmural linear lesion and the possibility of complications such as thrombus formation leading to thromboembolism, the catheter-based maze procedure remains problematic. We tested, in pigs, the possibility of using a temperature-controlled cooled-tip radiofrequency (RF) ablation system together with a realtime position management (RPM) system to create a transmural linear lesion uncomplicated by thrombus formation.Nine pigs underwent insertion of two electrode catheters (each with two ultrasound electrodes), one into the coronary sinus (CS) and one into the right ventricular apex (references for ultrasound-based non-fluoroscopic three-dimensional mapping). A cooled-tip catheter (with two ultrasound electrodes) was introduced into the right atrium. Linear right atrial ablation was performed with a custom radiofrequency (RF) generator. The catheter was perfused with 0.66 mL/second of saline. RF was delivered for 60 seconds at a target temperature of 40°C. A linear ablation line was created between the superior vena cava and inferior vena cava. Three-dimensional isochronal maps were created during CS pacing before and after ablation. In 4 of the 9 pigs, a transmural linear ablation line was confirmed by three-dimensional mapping and postmortem macroscopic examination. No endocardial thrombus formation was noted. Temperature-controlled cooled-tip RF linear ablation guided by an RPM system appears to have potential for creating linear lesions in the atria. Further studies are needed to determine whether such an ablation technique and the parameters used will facilitate successful completion of the catheter-based maze procedure.

  4. 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.

  5. Efficacy of needle-placement technique in radiofrequency ablation for treatment of lumbar facet arthropathy

    PubMed Central

    Loh, Jeffrey T; Nicol, Andrea L; Elashoff, David; Ferrante, F Michael

    2015-01-01

    Background Many studies have assessed the efficacy of radiofrequency ablation to denervate the facet joint as an interventional means of treating axial low-back pain. In these studies, varying procedural techniques were utilized to ablate the nerves that innervate the facet joints. To date, no comparison studies have been performed to suggest superiority of one technique or even compare the prevalence of side effects and complications. Materials and methods A retrospective chart review was performed on patients who underwent a lumbar facet denervation procedure. Each patient’s chart was analyzed for treatment technique (early versus advanced Australian), preprocedural visual numeric scale (VNS) score, postprocedural VNS score, duration of pain relief, and complications. Results Pre- and postprocedural VNS scores and change in VNS score between the two groups showed no significant differences. Patient-reported benefit and duration of relief was greater in the advanced Australian technique group (P=0.012 and 0.022, respectively). The advanced Australian technique group demonstrated a significantly greater median duration of relief (4 months versus 1.5 months, P=0.022). Male sex and no pain-medication use at baseline were associated with decreased postablation VNS scores, while increasing age and higher preablation VNS scores were associated with increased postablation VNS scores. Despite increasing age being associated with increased postablation VNS scores, age and the advanced Australian technique were found to confer greater patient self-reported treatment benefit. Conclusion The advanced Australian technique provides a significant benefit over the early Australian technique for the treatment of lumbar facet pain, both in magnitude and duration of pain relief. PMID:26504407

  6. 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

  7. 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.

  8. Combined Therapy of Radiofrequency Ablation and Ethanol Injection of Rabbit Liver: An In Vivo Feasibility Study

    SciTech Connect

    Lee, Jeong Min; Lee, Young Hwan; Kim, Young Kon; Kim, Sang Won; Kim, Chong Soo

    2004-03-15

    Our purpose was to compare the effects of percutaneous radiofrequency ablation (RFA) combined with percutaneous ethanol injection (PEI) on the extent of ablation in in vivo rabbit liver tissue as compared with either therapy alone. Twenty-two New Zealand white rabbits were included in this study and allocated into three groups: group A: conventional RFA (n = 6); group B: PEI (n = 6); group C: combined RFA and PEI (n = 10). For combined RFA and PEI, under ultrasound guidance, 1 mL of absolute ethanol was injected into the target area of the liver parenchyma through a 21-gauge Chiba needle before performing RFA. RFA was performed using a 17- gauge internally cooled electrode with 1-cm active tip, and RF energy (30 W) was applied for 3 minutes, with or without ethanol injection. After RFA or PEI, contrast-enhanced computed tomography and CT-pathologic correlation were performed. The short- axis and long-axis diameters of thermal lesions of each group were compared. All procedures were technically successful and a total of 38 lesions were produced. The mean short-axis and long-axis diameter of the coagulation necrosis in rabbits of group C (combination of RFA and PEI), were significantly larger than those of other groups: group A: 10.3 {+-} 2 mm and 11.4 {+-} 2 mm; group B: 3.1 {+-} 1 mm and 4.3 {+-} 2 mm; group C: 12.8 {+-} 3 mm and 17.8 {+-} 6 mm (p < 0.05). On contrast-enhanced CT scan, the lesions of rabbits of the group C appeared to be more frequently irregular compared to those of group A (20% in group A vs. 67% in group C). There were three complications including two localized hematomas and one cardiopulmonary failure. Combined RFA and PEI could increase the dimension of coagulation necrosis without increasing complications and therefore, may be successfully used for treating larger lesions.

  9. 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

  10. Right thoracic paravertebral anaesthesia for percutaneous radiofrequency ablation of liver tumours

    PubMed Central

    Cheung Ning, M; Karmakar, M K

    2011-01-01

    Objectives Percutaneous radiofrequency ablation (PRFA) of liver tumours performed under local anaesthesia and intravenous sedation can cause severe pain to patients. This prospective study evaluated the efficacy of a right thoracic paravertebral block (TPVB) for anaesthesia and analgesia during PRFA of liver tumours. Methods 20 patients, aged 44–74 years, with liver malignancies received a multiple injection TPVB at the T6–10 levels 30 min before the PRFA. An intravenous infusion of propofol (3–5 mg kg–1 h–1) was administered to patients who requested to be sedated and intravenous fentanyl (25 µg bolus) was administered as rescue analgesia. Pain during the TPVB and PRFA was assessed using a numerical rating scale (NRS; 0, no pain; 10, worst imaginable pain). Patients were also assessed for residual pain and analgesic consumption during the 24 h after the intervention. Results The TPVB was well tolerated and produced ipsilateral sensory anaesthesia with satisfactory spread (median (range); 8 (6–11) dermatomes). The PRFA procedure caused mild pain (mean (standard deviation, SD); NRS 1.4 (1.9)) during the insertion of the ablation needle and the peak pain intensity during the therapeutic burn was moderate (mean (SD); NRS 5.0 (3.3)) in severity. During the 24 h after the PRFA, patients reported minimal pain and consumed very few analgesics. The mean (SD) satisfaction score (0, totally dissatisfied; 10, very satisfied) of the patients was 8.9 (1.1) and that of the radiologists was 8.8 (1.4). Conclusion A right TPVB is safe and effective for anaesthesia and analgesia during PRFA of malignant liver tumours. PMID:21081575

  11. 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.

  12. 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

  13. 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

  14. Value of C-arm computed tomography in radiofrequency ablation of small lung lesions.

    PubMed

    Li, X Q; Zhang, Y; Huang, D B; Zhang, J; Zhang, G S; Wen, Z X; Li, J H; Liu, H L

    2014-08-07

    This study aimed to explore the value of C-arm computed tomography (CT) applications in radiofrequency ablation (RFA) of small lung lesions. The puncture success rate, cumulative survival rate, tumor response rate, complications, and radiation dose during C-arm CT-guided RFA of 36 small lung lesions in 34 patients were analyzed. In 35 RFA procedures for 36 small lung lesions, the puncture success rate was 100%. There were 7 cases of complications, including 4 cases of pneumothorax (puncture suction or closed chest drainage was not required) and 3 cases of hemoptysis. The cumulative survival rate in the 34 patients after RFA was 100% at 6 months, 69.0% at 1 year, and 60.0% at 2 years. In assessments of 36 foci imaged during the follow-up period, the total response rates at 1 month, 3 months, and 6 months were 77.8% (28/36), 69.7% (23/33), and 61.3% (19/31), respectively. The mean cumulative dose and average effective dose during surgery were 120.1 ± 61.4 mGy and 3.5 ± 1.7 mSv, respectively. The application of C-arm CT to RFA of small lung lesions could provide abundant information to the surgeon and increase the lesion puncture success rate and is considered to be a promising image-guided technology.

  15. 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.

  16. 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

  17. 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

  18. Factors for early tumor recurrence of single small hepatocellular carcinoma after percutaneous radiofrequency ablation therapy

    PubMed Central

    Yu, Hsien-Chung; Cheng, Jin-Shiung; Lai, Kwok-Hung; Lin, Chi-Pin; Lo, Gin-Ho; Lin, Chiun-Ku; Hsu, Ping-I; Chan, Hoi-Hung; Lo, Ching-Chu; Tsai, Wei-Lun; Chen, Wen-Chi

    2005-01-01

    AIM: To evaluate the factors affecting the early tumor recurrence within one year in cirrhotic patients having a single small hepatocellular carcinoma (HCC) after complete tumor necrosis by radiofrequency ablation (RFA) therapy. METHODS: Thirty patients with a single small HCC received RFA therapy by a RFA 2000 generator with LeVeen needle. Tri-phase computerized tomogram was followed every 2 to 3 mo after RFA. The clinical effects and tumor recurrence were recorded. RESULTS: The initial complete tumor necrosis rate was 86.7%. Twenty-two patients were followed for more than one year. The local and overall recurrence rates were 13.6% and 36.4%, 33.3% and 56.2%, 46.6% and 56.2% at 12, 24 and 30 mo, respectively. No major complication or procedure-related mortality was found. The risk factors for early local tumor recurrence within one year were larger tumor size, poor pathologic differentiation of tumor cells and advanced tumor staging. The age of patients with new tumor formation within one year was relatively younger (55.1±8.3 vs 66.7±10.8, P = 0.029). CONCLUSION: Large tumor size, poor pathologic differentiation of tumor cells and advanced tumor staging are the risk factors for early local tumor recurrence within one year, and young age is the positive predictor for new tumor formation within one year. PMID:15770718

  19. MR monitoring of MR-guided radiofrequency thermal ablation of normal liver in an animal model.

    PubMed

    Boaz, T L; Lewin, J S; Chung, Y C; Duerk, J L; Clampitt, M E; Haaga, J R

    1998-01-01

    The purpose of this study was to determine the suitability of MRI to accurately detect radiofrequency (RF) thermoablative lesions created under MR guidance. In vivo RF lesions were created in the livers of six New Zealand White rabbits using a 2-mm-diameter titanium alloy RF electrode with a 20-mm exposed tip and a 50-W RF generator. This was performed using a 0.2T clinical C-arm MR imager for guidance and monitoring. Each animal was sacrificed and gross evaluation was performed. Histologic correlation was performed on the first two animals. The MR-compatible RF electrode was easily identified on rapid gradient-echo images used to guide electrode placement. A single lesion was created in each rabbit liver. Lesions ranged from approximately 10 to 17 mm in diameter (mean, 13.5 mm). T2-weighted and short T1 inversion recovery (STIR) images demonstrated lesions ranging in diameter from 12 to 18 mm (mean, 14.6 mm). Lesion dimensions determined from images closely correlated with those determined at gross examination with the discrepancy never exceeding 2 mm, for an r2 value of .87. MRI performed at the time of MR-guided RF ablation accurately demonstrated created lesions. This modality may provide a new option for the treatment of local and regional neoplastic disease. PMID:9500262

  20. 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.

  1. 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.

  2. 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. PMID:27556089

  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. Ibutilide for the Cardioversion of Paroxysmal Atrial Fibrillation during Radiofrequency Ablation of Supraventricular Tachycardias

    PubMed Central

    Polymeropoulos, Kostas; Vassilikos, Vassilios P.; Mantziari, Lilian; Paraskevaidis, Stelios; Karamitsos, Theodoros D.; Mochlas, Sotirios; Parcharidis, Georgios; Louridas, Georgios; Styliadis, Ioannis H.

    2011-01-01

    Direct current electrical cardioversion (DC-ECV) is the preferred treatment for the termination of paroxysmal atrial fibrillation (AF) that occurs during radiofrequency ablation (RFA) of supraventricular tachycardias (SVT). Intravenous Ibutilide may be an alternative option in this setting. Thirty-four out of 386 patients who underwent SVT-RFA presented paroxysmal AF during the procedure and were randomized into receiving ibutilide or DC-ECV. Ibutilide infusion successfully cardioverted 16 out of 17 patients (94%) within 17.37 ± 7.87  min. DC-ECV was successful in all patients (100%) within 17.29 ± 3.04  min. Efficacy and total time to cardioversion did not differ between the study groups. No adverse events were observed. RFA was successfully performed in 16 patients (94%) in the ibutilide arm and in all patients (100%) in the DC-ECV arm, p = NS. In conclusion, ibutilide is a safe and effective alternative treatment for restoring sinus rhythm in cases of paroxysmal AF complicating SVT-RFA. PMID:21738857

  5. Complications of radiofrequency ablation of hepatic tumors: Frequency and risk factors

    PubMed Central

    Fonseca, Alexandre Zanchenko; Santin, Stephanie; Gomes, Luiz Guilherme Lisboa; Waisberg, Jaques; Ribeiro Jr., Marcelo Augusto Fontenelle

    2014-01-01

    Radiofrequency ablation (RFA) has become an important option in the therapy of primary and secondary hepatic tumors. Surgical resection is still the best treatment option, but only a few of these patients are candidates for surgery: multilobar disease, insufficient liver reserve that will lead to liver failure after resection, extra-hepatic disease, proximity to major bile ducts and vessels, and co-morbidities. RFA has a low mortality and morbidity rate and is considered to be safe. Thus, complications occur and vary widely in the literature. Complications are caused by thermal damage, direct needle injury, infection and the patient’s co-morbidities. Tumor type, type of approach, number of lesions, tumor localization, underlying hepatic disease, the physician’s experience, associated hepatic resection and lesion size have been described as factors significantly associated with complications. The physician in charge should promptly recognize high-risk patients more susceptible to complications, perform a close post procedure follow-up and manage them early and adequately if they occur. We aim to describe complications from RFA of hepatic tumors and their risk factors, as well as a few techniques to avoid them. This way, others can decrease their morbidity rates with better outcomes. PMID:24672640

  6. Osteoid osteoma of the femur in a 7-month-old infant treated with radiofrequency ablation

    PubMed Central

    Virayavanich, Warapat; Singh, Ravi; O’Donnell, Richard J.; Horvai, Andrew E.; Goldsby, Robert E.

    2010-01-01

    Osteoid osteoma occurs most commonly in children, adolescents, and young adults between the ages of 5 and 30 years. In the preschool age group, it is quite uncommon, accounting for only 3–8% of all osteoid osteoma cases. We report a case of osteoid osteoma in a 7-month-old infant, who presented with decreased use of the right lower extremity due to pain. Magnetic resonance imaging (MRI) showed an atypical appearance. A biopsy of the lesion, with histopathological examination, confirmed the diagnosis of osteoid osteoma. Radiofrequency ablation (RFA) of the nidus under computed tomography (CT) guidance was performed. The patient developed a recurrence after 3 months, which was treated with a second RFA. On subsequent follow-up, the infant did not show signs of pain after 1 month. In summary, this case report shows that osteoid osteoma can present in early infancy and can be successfully treated with RFA at this age, however, recurrence after the procedure can occur and close follow-up is recommended. PMID:20694724

  7. 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

  8. 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

  9. Plasma-mediated radiofrequency ablation followed by percutaneous cementoplasty under fluoro-CT guidance: a case report

    PubMed Central

    Laganà, Domenico; Ianniello, Andrea; Fontana, Federico; Mangini, Monica; Mocciardini, Lucia; Spanò, Emanuela; Piacentino, Filippo; Cuffari, Salvatore; Fugazzola, Carlo

    2009-01-01

    We report a case of a 81-year-old Caucasian man with colorectal carcinoma, treated by surgery in 1998, referred for palliative treatment of a refractory painful caused by osteolytic metastases of 2.5 cm in back-upper ilium spine. Plasma-mediated radiofrequency ablation was performed under conscious sedation, using Fluoroscopic Computer Tomography guidance. After completing the ablation phase of the procedure, a mixture of bone cement and Biotrace sterile barium sulfate was injected into the ablated cavity. Patient was evaluated by using the Brief Pain Inventory and considering pain interference with daily living at day 1 and 3 and week 1, 2, 3, 4 by means of a telephone interview. A post-procedure Computer Tomography scan was performed to examine the distribution of cement deposition few minutes after the procedure. The plasma mediated RFA and cementoplasty were well tolerated by the patient who did not develop any complication. PMID:19918385

  10. Successful radiofrequency catheter ablation of atrioventricular nodal reentrant tachycardia in a patient with dextrocardia due to unilateral pulmonary agenesis: a case report

    PubMed Central

    Aksu, Tolga; Guler, Tumer Erdem; Golcuk, Ebru; Erden, Ismail; Ozcan, Kazım Serhan

    2015-01-01

    Radiofrequency catheter ablation of the slow pathway is considered to be the treatment of choice for patients with atrioventricular nodal reentrant tachycardia. We report a 34-year-old female with mirror image dextrocardia due to unilateral pulmonary agenesis who underwent successful slow pathway ablation for typical atrioventricular nodal reentrant tachycardia. Using contrast injection, cardiac anatomy was identified in a short time and successfully ablated. PMID:25674017

  11. 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.

  12. Feasibility of Extracted-Overlay Fusion Imaging for Intraoperative Treatment Evaluation of Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Makino, Yuki; Imai, Yasuharu; Igura, Takumi; Kogita, Sachiyo; Sawai, Yoshiyuki; Fukuda, Kazuto; Iwamoto, Takayuki; Okabe, Junya; Takamura, Manabu; Fujita, Norihiko; Hori, Masatoshi; Takehara, Tetsuo; Kudo, Masatoshi; Murakami, Takamichi

    2016-01-01

    Background and Aims Extracted-overlay fusion imaging is a novel computed tomography/magnetic resonance-ultrasonography (CT/MR-US) imaging technique in which a target tumor with a virtual ablative margin is extracted from CT/MR volume data and synchronously overlaid on US images. We investigated the applicability of the technique to intraoperative evaluation of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Methods This retrospective study analyzed 85 HCCs treated with RFA using extracted-overlay fusion imaging for guidance and evaluation. To perform RFA, an electrode was inserted targeting the tumor and a virtual 5-mm ablative margin overlaid on the US image. Following ablation, contrast-enhanced US (CEUS) was performed to assess the ablative margin, and the minimal ablative margins were categorized into three groups: (I) margin <0 mm (protrusion), (II) margin 0 to <5 mm, and (III) margin ≥5 mm. Margin assessment was based on the positional relationship between the overlaid tumor plus margin and the perfusion defect of the ablation zone. Tumors in group I underwent repeat ablation until they were in groups II or III. The final classifications were compared with those obtained by retrospectively created fusion images of pre- and post-RFA CT or MR imaging (CT-CT/MR-MR fusion imaging). Results Treatment evaluation was impossible using CEUS in six HCCs because the tumors were located far below the body surface. Of the remaining 79 HCCs, the categorizations of minimal ablative margins between CEUS extracted-overlay fusion imaging and CT-CT/MR-MR fusion imaging were in agreement for 72 tumors (91.1%) (Cohen's quadratic-weighted kappa coefficient 0.66, good agreement, p<0.01). Conclusions Extracted-overlay fusion imaging combined with CEUS is feasible for the evaluation of RFA and enables intraoperative treatment evaluation without the need to perform contrast-enhanced CT. PMID:27781199

  13. 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.

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

    PubMed Central

    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

  15. 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

  16. Irrigated and non-irrigated radiofrequency ablation systems and ways of non-irrigated RF systems development

    NASA Astrophysics Data System (ADS)

    Evtushenko, A. V.; Evtushenko, V. V.; Bykov, A. N.; Sergeev, V. S.; Syryamkin, V. I.; Kistenev, Yu. V.; Anfinogenova, Ya. D.; Smyshlyaev, K. A.; Kurlov, I. O.

    2015-11-01

    Improving of radiofrequency ablation systems for the myocardium is one of the fundamental problems of cardiac surgery. We used pig left ventricular myocardium as a working model. Mean thickness of the left ventricular wall was 10.1 ± 5.6 mm. The studies were performed on 10 hearts. The mean weight of hearts was 294.7 ± 21g. Research is being done on the electrophysical bench in 2 stages. In the first stage the hearts were placed on the electrophysical bench and heated to 36.6°C. In the second stage heart cooled to 20°C. The monopolar radiofrequency exposure was processing on the myocardium by two types of electrodes: spherical irrigated electrode and non-irrigated penetrating one within 20 seconds. The electrical resistance of the myocardium was measured at different temperatures before and after exposure. This paper shows that the decrease in ambient temperature combined with using of new penetrating electrodes for radiofrequency ablation gives better results than using of irrigated and non-irrigated systems. This method allows significantly reduce time exposure for a maximum depth of destruction in the myocardium.

  17. 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

  18. Photoreceptor Ablation Initiates the Immediate Loss of Glutamate Receptors in Postsynaptic Bipolar Cells in Retina

    PubMed Central

    2015-01-01

    Structural changes underlying neurodegenerative diseases include dismantling of synapses, degradation of circuitry, and even massive rewiring. Our limited understanding of synapse dismantling stems from the inability to control the timing and extent of cell death. In this study, selective ablation of cone photoreceptors in live mouse retina and tracking of postsynaptic partners at the cone-to-ON cone bipolar cell synapse reveals that early reaction to cone loss involves rapid and local changes in postsynaptic glutamate receptor distribution. Glutamate receptors disappear with a time constant of 2 h. Furthermore, binding of glutamate receptors by agonists and antagonists is insufficient to rescue glutamate receptor loss, suggesting that receptor allocation depends on the physical presence of cones. These findings demonstrate that the initial step in synapse disassembly involves postsynaptic receptor loss rather than dendritic retraction, providing insight into the early stages of neurodegenerative disease. PMID:25673837

  19. 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

  20. 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

  1. 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

  2. Photodynamic therapy vs radiofrequency ablation for Barrett’s dysplasia: Efficacy, safety and cost-comparison

    PubMed Central

    Ertan, Atilla; Zaheer, Irum; Correa, Arlene M; Thosani, Nirav; Blackmon, Shanda H

    2013-01-01

    AIM: To compare effectiveness, safety, and cost of photodynamic therapy (PDT) and radiofrequency ablation (RFA) in treatment of Barrett’s dysplasia (BD). METHODS: Consecutive case series of patients undergoing either PDT or RFA treatment at single center by a single investigator were compared. Thirty-three patients with high-grade dysplasia (HGD) had treatment with porfimer sodium photosensitzer and 630 nm laser (130 J/cm), with maximum of 3 treatment sessions. Fifty-three patients with BD (47 with low-grade dysplasia -LGD, 6 with HGD) had step-wise circumferential and focal ablation using the HALO system with maximum of 4 treatment sessions. Both groups received proton pump inhibitors twice daily. Endoscopic biopsies were acquired at 2 and 12 mo after enrollment, with 4-quadrant biopsies every 1 cm of the original BE extent. A complete histological resolution response of BD (CR-D) was defined as all biopsies at the last endoscopy session negative for BD. Fisher’s exact test was used to assess differences between the two study groups for primary outcomes. For all outcomes, a two-sided P value of less than 0.05 was considered to indicate statistical significance. RESULTS: Thirty (91%) PDT patients and 39 (74%) RFA were men (P = 0.05). The mean age was 70.7 ± 12.2 and 65.4 ± 12.7 (P = 0.10) year and mean length of BE was 5.4 ± 3.2 cm and 5.7 ± 3.2 cm (P = 0.53) for PDT and RFA patients, respectively. The CR-D was (18/33) 54.5% with PDT vs (47/53) 88.7% with RFA (P = 0.001). One patient with PDT had an esophageal perforation and was managed with non-surgical measures and no perforation was seen with RFA. PDT was five times more costly than RFA at our institution. The two groups were not randomized and had different BD grading are the limitations of the study. CONCLUSION: In our experience, RFA had higher rate of CR-D without any serious adverse events and was less costly than PDT for endoscopic treatment of BD. PMID:24222954

  3. Radiofrequency Ablation Versus Endoscopic Submucosal Dissection in Treating Large Early Esophageal Squamous Cell Neoplasia

    PubMed Central

    Wang, Wen-Lun; Chang, I-Wei; Chen, Chien-Chuan; Chang, Chi-Yang; Mo, Lein-Ray; Lin, Jaw-Town; Wang, Hsiu-Po; Lee, Ching-Tai

    2015-01-01

    Abstract Radiofrequency ablation (RFA) and endoscopic submucosal dissection (ESD) can potentially be applied for early esophageal squamous cell neoplasia (ESCN); however, no study has directly compared these 2 modalities. We retrospectively enrolled the patients with flat-type “large” (length ≥3 cm extending ≥1/2 of the circumference of esophagus) early ESCNs treated endoscopically. The main outcome measurements were complete response at 12 months, and adverse events. Of a total of 65 patients, 18 were treated with RFA and 47 with ESD. The procedure time of RFA was significantly shorter than that of ESD (126.6 vs 34.8 min; P < 0.001). The complete resection rate of ESD and complete response rate after primary RFA were 89.3% and 77.8%, respectively. Based on the histological evaluation of the post-ESD specimens showed 14 of 47 (29.8%) had histological upstaging compared with the pre-ESD biopsies, and 4 of them had lymphovascular invasion requiring chemoradiation or surgery. After additional therapy for residual lesions, 46 (97.9%) patients in the ESD group and 17 (94.4%) patients in the RFA group achieved a complete response at 12 months. Four patients (8.5%) developed major procedure-related adverse events in the ESD group, but none in the RFA group. In patients with lesions occupying more than 3/4 of the circumference, a significantly higher risk of esophageal stenosis was noted in the ESD group compared with RFA group (83% vs 27%, P = 0.01), which required more sessions of dilatation to resolve the symptoms (median, 13 vs 3, P = 0.04). There were no procedure-related mortality or neoplastic progression in either group; however, 1 patient who received ESD and 1 who received RFA developed local recurrence during a median follow-up period of 32.4 (range, 13–68) and 18.0 (range, 13–41) months, respectively. RFA and ESD are equally effective in the short-term treatment of early flat large ESCNs; however, more adverse events occur with ESD

  4. Radiofrequency Ablation of Non-Small-Cell Carcinoma of the Lung Under Real-Time FDG PET CT Guidance

    SciTech Connect

    Schoellnast, Helmut; Larson, Steven M.; Nehmeh, Sadek A.; Carrasquillo, Jorge A.; Thornton, Raymond H.; Solomon, Stephen B.

    2011-02-15

    Radiofrequency ablation (RFA) is a well-established method in treatment of patients with lung carcinomas who are not candidates for surgical resection. Usually computed tomographic (CT) guidance is used for the procedure, thus enabling needle placement and permitting evaluation of complications such as pneumothorax and bleeding. {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is generally used for tumor activity assessment and is therefore useful in follow-up after tumor treatment. A method that provides real-time image-based monitoring of RFA to ensure complete tumor ablation would be a valuable tool. In this report, we describe the behavior of preinjected FDG during PET CT-guided RFA of a non-small-cell lung carcinoma and discuss the value of FDG as a tool to provide intraprocedure monitor ablation. The size and the form of the activity changed during ablation. Ablation led to increase of the size and blurring and irregularity of the contour compared to pretreatment imaging. The maximal standardized uptake value decreased only slightly during the procedure. Therefore, before RFA, FDG PET can guide initial needle placement, but it does not serve as a monitoring tool to evaluate residual viable tissue during the procedure.

  5. 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

  6. 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.

  7. 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

  8. Pediatric Tachyarrhythmia and Radiofrequency Catheter Ablation: Results From 1993 to 2011

    PubMed Central

    Park, Hyoung-Seob; Hyun, Myung Chul; Kim, Yoon-Nyun

    2012-01-01

    Background and Objectives We performed a retrospective study to elucidate the frequency of tachycardia mechanisms and the characteristics of accessory pathways (APs), confirmed by radiofrequency catheter ablation (RFCA) in pediatric tachycardia. In addition, we analyzed the efficacy and safety of pediatric RFCA. Subjects and Methods The authors retrospectively reviewed the records of a total of 260 patients (aged 2 to 18 years) who had undergone RFCA between August 1993 and July 2011 at two medical centers in Daegu. Results Two hundred and sixty patients underwent 272 RFCAs at less than 18 years of age. Of these 260 patients, 9 patients (3%) were younger than 6 years, and 175 patients (67%) were older than 12 years. The tachycardia mechanisms observed were atrioventricular reentry tachycardia (AVRT) in 175 patients (65%), atrioventricular nodal reentry tachycardia (AVNRT) in 83 patients (30%), ventricular tachycardia in 12 patients (4%), and atrial tachycardia in 2 patients (0.7%). Among the patients with AVRT, there were 94 concealed APs and 81 manifest APs. Left-side APs were more common in concealed APs than in manifest APs (72/94, 77% vs. 33/81, 41%, p<0.001). Sixty-six percent (55/83) of AVNRT cases were located at the M1 and/or M2 sites. Four patients had multiple tachycardia mechanisms (AVNRT+AVRT) and 9 patients had multiple APs. The recurrence rate was 5% (13/272). Of these recurrent cases, 12 patients had AVRT. The overall success rate was 95%. Conclusion Pediatric RFCA provides a good success rate and an acceptable recurrence. In addition, we suggest that the APs location may be associated with concealed or manifest property of APs. PMID:23236324

  9. European survey on efficacy and safety of duty-cycled radiofrequency ablation for atrial fibrillation

    PubMed Central

    Scharf, C.; Ng, G.A.; Wieczorek, M.; Deneke, T.; Furniss, S.S.; Murray, St.; Debruyne, Ph.; Hobson, N.; Berntsen, R.F.; Schneider, M.A.; Hauer, H.A.; Halimi, F.; Boveda, S.; Asbach, S.; Boesche, L.; Zimmermann, M.; Brigadeau, F.; Taieb, J.; Merkel, M.; Pfyffer, M.; Brunner-La Rocca, H.P.; Boersma, L.V.A.

    2012-01-01

    Aims Duty-cycled radiofrequency ablation (RFA) has been used for atrial fibrillation (AF) for around 5 years, but large-scale data are scarce. The purpose of this survey was to report the outcome of the technique. Methods and results A survey was conducted among 20 centres from seven European countries including 2748 patients (2128 with paroxysmal and 620 with persistent AF). In paroxysmal AF an overall success rate of 82% [median 80%, interquartile range (IQR) 74–90%], a first procedure success rate of 72% [median 74% (IQR 59–83%)], and a success of antiarrhythmic medication of 59% [median 60% (IQR 39–72%)] was reported. In persistent AF, success rates were significantly lower with 70% [median 74% (IQR 60–92%)]; P = 0.05) as well as the first procedure success rate of 58% [median 55% (IQR 47–81%)]; P = 0.001). The overall success rate was similar among higher and lower volume centres and were not dependent on the duration of experience with duty-cycled RFA (r = −0.08, P = 0.72). Complications were observed in 108 (3.9%) patients, including 31 (1.1%) with symptomatic transient ischaemic attack or stroke, which had the same incidence in paroxysmal and persistent AF (1.1 vs. 1.1%) and was unrelated to the case load (r = 0.24, P = 0.15), bridging anticoagulation to low molecular heparin, routine administration of heparin over the long sheath, whether a transoesophageal echocardiogram was performed in every patient or not and average procedure times. Conclusion Duty-cycled RFA has a self-reported success and complication rate similar to conventional RFA. After technical modifications a prospective registry with controlled data monitoring should be conducted to assess outcome. PMID:22772054

  10. 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.

  11. 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.

  12. Patient Characteristics and the Incidence of Radiation-induced Dermatitis Following Radiofrequency Catheter Ablation

    PubMed Central

    Cha, Myung-Jin; Jo, Seong Jin; Cho, Youngjin; Choi, Eue-Keun

    2016-01-01

    Background and Objectives Radiofrequency catheter ablation (RFCA) exposes patients to fixed angle radiation for extended periods of time. We investigated the incidence and characteristics of radiation-induced dermatitis (RID) associated with RFCA. Subjects and Methods We screened 1347 consecutive patients from 2000 to 2011 who underwent RFCA for any indication and reviewed patients with dermatologic issues at the 1-month follow-up. Skin lesions were classified into three groups: most likely RID, probable RID, and possible RID. Results Of the 1347 enrolled patients, 12 (0.89%) experienced dermatologic issues within 1 month after RFCA, including six patients (0.45%) clinically classified as 'most likely RID' and four patients (0.30%) with 'probable RID'. Ten patients, including most likely RID or probable RID patients, developed skin lesions on the right back and upper arm. Skin lesions did not improve without meticulous treatment, and three cases required surgical intervention. We compared the RID group to the remaining 1335 patients (normal group). The mean body mass indices (BMIs) of the RID and normal groups were 29.3 and 23.9 kg/m2, respectively (p<0.001). Radiation exposure times were longer in the RID group (180±31.0 vs. 47±49.9 minutes, p<0.001). We further analyzed 44 patients (6 RID cases and 38 normal patients) that had BMIs >26 kg/m2 and exposure times >115 minutes based on receiver operator characteristic curve analyses. Among the 35 patients without RID, 29 patients (82.9%) did not use biplane fluoroscopy. Conclusions Patients with high BMIs have a higher risk of developing severe RID with increasing fluoroscopy times using biplane fluoroscopy. PMID:27721855

  13. 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.

  14. Delayed Surgery for Parathyroid Adenoma Misdiagnosed as a Thyroid Nodule and Treated with Radiofrequency Ablation

    PubMed Central

    Kim, Ho-Su; Choi, Bong Hoi; Park, Jung Rang; Hahm, Jong Ryeal; Jung, Jung Hwa; Kim, Soo Kyoung; Kim, Sungsu; Kim, Kyong-Young; Chung, Soon Il

    2013-01-01

    Primary hyperparathyroidism occurs as a result of isolated parathyroid adenoma in 80% to 85% of all cases. A 99mtechnetium (99mTc) sestamibi scan or neck ultrasonography is used to localize the neoplasm prior to surgical intervention. A 53-year-old female was referred for the exclusion of metabolic bone disease. She presented with low back pain that had persisted for the past 6 months and elevated serum alkaline phosphatase (1,253 IU/L). Four years previously, she had been diagnosed at a local hospital with a 2.3-cm thyroid nodule, which was determined to be pathologically benign. Radiofrequency ablation was performed at the same hospital because the nodule was still growing during the follow-up period 2 years before the visit to our hospital, and the procedure was unsuccessful in reducing the size of the nodule. The results of the laboratory tests in our hospital were as follows: serum calcium, 14.6 mg/dL; phosphorus, 3.5 mg/dL; and intact parathyroid hormone (iPTH), 1,911 pg/mL. Neck ultrasonography and 99mTc sestamibi scan detected a 5-cm parathyroid neoplasm in the left lower lobe of the patient's thyroid; left parathyroidectomy was performed. This case indicated that thyroid ultrasonographers and pathologists need to be experienced enough to differentiate a parathyroid neoplasm from a thyroid nodule; 99mTc sestamibi scan, serum calcium, and iPTH levels can help to establish the diagnosis of parathyroid neoplasm. PMID:24396684

  15. 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

  16. 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.

  17. Outcomes After Stereotactic Body Radiotherapy or Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Wahl, Daniel R.; Stenmark, Matthew H.; Tao, Yebin; Pollom, Erqi L.; Caoili, Elaine M.; Lawrence, Theodore S.; Schipper, Matthew J.

    2016-01-01

    Purpose Data guiding selection of nonsurgical treatment of hepatocellular carcinoma (HCC) are lacking. We therefore compared outcomes between stereotactic body radiotherapy (SBRT) and radiofrequency ablation (RFA) for HCC. Patients and Methods From 2004 to 2012, 224 patients with inoperable, nonmetastatic HCC underwent RFA (n = 161) to 249 tumors or image-guided SBRT (n = 63) to 83 tumors. We applied inverse probability of treatment weighting to adjust for imbalances in treatment assignment. Freedom from local progression (FFLP) and toxicity were retrospectively analyzed. Results RFA and SBRT groups were similar with respect to number of lesions treated per patient, type of underlying liver disease, and tumor size (median, 1.8 v 2.2 cm in maximum diameter; P = .14). However, the SBRT group had lower pretreatment Child-Pugh scores (P = .003), higher pretreatment alpha-fetoprotein levels (P = .04), and a greater number of prior liver-directed treatments (P < .001). One- and 2-year FFLP for tumors treated with RFA were 83.6% and 80.2% v 97.4% and 83.8% for SBRT. Increasing tumor size predicted for FFLP in patients treated with RFA (hazard ratio [HR], 1.54 per cm; P = .006), but not with SBRT (HR, 1.21 per cm; P = .617). For tumors ≥ 2 cm, there was decreased FFLP for RFA compared with SBRT (HR, 3.35; P = .025). Acute grade 3+ complications occurred after 11% and 5% of RFA and SBRT treatments, respectively (P = .31). Overall survival 1 and 2 years after treatment was 70% and 53% after RFA and 74% and 46% after SBRT. Conclusion Both RFA and SBRT are effective local treatment options for inoperable HCC. Although these data are retrospective, SBRT appears to be a reasonable first-line treatment of inoperable, larger HCC. PMID:26628466

  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. Case Study of Hepatic Radiofrequency Ablation Causing a Systemic Inflammatory Response Under Total Intravenous Anesthesia

    PubMed Central

    Schälte, Gereon; Henzler, Dietrich; Waning, Christian; Tacke, Josef; Rossaint, Rolf

    2010-01-01

    Objective To investigate the effects of hepatic radiofrequency ablation (RFA) in patients with malignant liver disease with respect to inflammation activation and stress response. Materials and Methods In an observational trial, we investigated the physiologic parameters of 17 patients (20 interventions) who underwent percutaneous RFA under general anesthesia after applying total intravenous anesthesia. TNFα, IL-6, IL-8, IL-10, adrenaline and noradrenaline, liver enzymes, lactate and creatine kinase were determined pre-interventionally after induction of anesthesia (T1), 90 minutes after initiation of RFA (T2), immediately after the conclusion of the procedure (T3), and 24 hours after the procedure (T4). Results A significant increase in body temperature (p < 0.001), and mean arterial pressure (p = 0.001) were measured intraoperatively (T2) and the day after the procedure (T4). Increased levels of IL-6 were measured at T3 and T4 (p = 0.001). IL-10 increased immediately after the procedure (T3; p = 0.007). IL-6 levels correlated well with the total energy applied (r = 0.837). Significant increases in the levels of adrenaline and noradrenaline were present at T3 and T4 (p < 0.001). The RFA-induced destruction of hepatic tissue was associated with increased levels of AST, ALT, GLDH and LDH. Conclusion Percutaneous RFA of hepatic malignancies causes an inflammatory and endocrine activation, similar to the systemic inflammatory response syndrome. These effects have to be taken in account when dealing with patients susceptible to sepsis or multi-organ failure. PMID:21076590

  20. 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

  1. 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

  2. Third-degree burn from cooled radiofrequency ablation of medial branch nerves for treatment of thoracic facet syndrome.

    PubMed

    Walega, David; Roussis, Christiana

    2014-07-01

    Radiofrequency ablation of medial branch nerves is considered a safe and effective treatment for chronic facet joint pain in the cervical, thoracic, and lumbosacral spine. Cooled radiofrequency ablation (C-RFA) is gaining popularity over conventional thermal radiofrequency ablation (RFA) in pain management. However, complications of C-RFA have not been reported in the literature. We present a first report of third-degree skin burn resulting from C-RFA electrode use for the treatment of facet syndrome. A 61-year-old woman (BMI of 21.8 kg/m(2) ) with thoracic facet syndrome underwent C-RFA of the T1-4 medial branch nerves (Thoracool System, Baylis Medical Company, Montreal, QC, Canada). Lesioning at the superior-lateral aspect of the thoracic transverse processes at each level was performed. During lesioning of the T2 MBN on the T3 transverse process, skin blanching 15 mm in diameter was noted around the introducer needle with patient complaints of severe, localized pain. Postprocedurally the skin injury at this level worsened in appearance, with a 20 mm × 4 mm skin defect, which took nearly 5 months to heal. With C-RFA, internally cooled electrodes are capable of creating large volume spherical lesions, a size advantage over conventional RFA. Although C-RFA lesion size may overcome the anatomic variability of target nerve location and potentially improve pain outcomes, added vigilance is required in thin patients and in anatomic regions of minimal subcutaneous tissue between the lesion target and the dermis. Skin burns at the site of the RF electrode are a potential risk under such conditions. PMID:24796394

  3. Radio Frequency Ablation in the Rabbit Lung Using Wet Electrodes: Comparison of Monopolar and Dual Bipolar Electrode Mode

    PubMed Central

    Park, Sang Hee; Han, Young Min; Chung, Gyung Ho; Kwak, Hyo Sung; Jeon, Soo bin; Lee, Yong Chul

    2006-01-01

    Objective To compare the effect of radio frequency ablation (RFA) on the dimensions of radio frequency coagulation necrosis in a rabbit lung using a wet electrode in monopolar mode with that in dual electrode bipolar mode at different infusion rates (15 mm/hr versus 30 ml/hr) and saline concentrations (0.9% normal versus 5.8% hypertonic saline). Materials and Methods Fifty ablation zones (one ablation zone in each rabbit) were produced in 50 rabbits using one or two 16-guage wet electrodes with a 1-cm active tip. The RFA system used in the monopolar and dual electrode wet bipolar RFA consisted of a 375-kHz generator (Elektrotom HiTT 106, Berchtold, Medizinelektronik, Germany). The power used was 30 watts and the exposure time was 5 minutes. The rabbits were assigned to one of five groups. Group A (n = 10) was infused with 0.9% NaCl used at a rate of 30 ml/hr in a monopolar mode. Groups B (n = 10) and C (n = 10) were infused with 0.9% NaCl at a rate of 15 and 30 ml/hr, respectively in dual electrode bipolar mode; groups D (n = 10) and E (n = 10) were infused with 5.8% NaCl at a rate of 15 and 30 ml/hr, respectively in a dual electrode bipolar mode. The dimensions of the ablation zones in the gross specimens from the groups were compared using one-way analysis of variance by means of the Scheffe test (post-hoc testing). Results The mean largest diameter of the ablation zones was larger in dual electrode bipolar mode (30.9±4.4 mm) than in monopolar mode (22.5±3.5 mm). The mean smallest diameter of the ablation zones was larger in dual electrode bipolar mode (22.3±2.5 mm) than in monopolar mode (19.5±3.5 mm). There were significant differences in the largest and smallest dimension between the monopolar (group A) and dual electrode wet bipolar mode (groups B-E). In dual electrode bipolar mode, the mean largest diameter of the ablation zones was larger at an infusion rate of 15 ml/hr (34.2±4.0 mm) than at 30 ml/hr (27.6±0.1 mm), and the mean smallest diameter of

  4. Recurrent oesophageal intramucosal squamous carcinoma treated by endoscopic mucosal resection and subsequent radiofrequency ablation using HALO system

    PubMed Central

    Kajzrlikova, Ivana; Vitek, Petr; Falt, Premysl; Urban, Ondrej; Kominek, Pavel

    2010-01-01

    The method of radiofrequency ablation (RFA) is currently used for the treatment of high-grade dysplasia in Barrett's oesophagus. It has theoretical potential also for the use in squamous epithelial neoplasias. The authors present a case report of an early diagnosis of squamous cancer in a high-risk patient, its endoscopic treatment and follow-up, and successful RFA of recurrent neoplasia. RFA can expand our therapeutic possibilities for the management of recurrent neoplastic lesions after endoscopic treatment of squamous oesophageal cancer. PMID:22802374

  5. 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

  6. Histopomorphic evaluation of radiofrequency mediated débridement chondroplasty.

    PubMed

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

    2010-06-29

    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

  7. 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

  8. 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

  9. 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

  10. Radiofrequency catheter ablation for idiopathic right ventricular tachycardia with special reference to morphological variation and long-term outcome.

    PubMed Central

    Chinushi, M.; Aizawa, Y.; Takahashi, K.; Kitazawa, H.; Shibata, A.

    1997-01-01

    OBJECTIVE: To assess the long term outcome of radiofrequency (RF) catheter ablation for idiopathic ventricular tachycardia (VT) originating from the outflow tract of the right ventricle, with special reference to the morphological variation in the VT-QRS complexes. PATIENTS: 13 patients whose ventricular tachycardia was treated with RF ablation were followed up more than 18 months after RF ablation. RESULTS: Endocardial mapping revealed the various extensions of ventricular tachycardia origin (from 0.5 x 0.5 cm to 2.0 x 2.0 cm) in which the earliest local electrogram was recorded during ventricular tachycardia. In all five tachycardias from a relatively wider origin (more than 0.5 x 0.5 cm) and in four of eight from a narrow origin (< 0.5 x 0.5 cm), subtle morphological variation in the VT-QRS complexes was observed. In tachycardias with morphological variation, the local electrogram at the tachycardia origin also showed concomitant variation in morphology and activation sequence. Ventricular tachycardia from a narrow site was eliminated by RF ablation to the confined site, but a larger number of RF applications was required in tachycardias from a wider origin. All 13 tachycardias were successfully ablated by RF current, and during the follow up period of 28.2 (SD 7.2) months, recurrence was observed in only one patient who had a wider origin. CONCLUSIONS: Long term efficacy of RF ablation was excellent in idiopathic ventricular tachycardia originating from the outflow tract of the right ventricle. Subtle morphological variations were frequently observed in this type of ventricular tachycardia, and about half of them represented a relatively wider arrhythmogenic area. PMID:9391287

  11. Radiofrequency ablation using BarRx for the endoscopic treatment of radiation proctopathy: a series of three cases

    PubMed Central

    Patel, Anish; Pathak, Rahul; Deshpande, Vrushak; Patel, Sunil H; Wickremesinghe, Prasanna C; Vadada, Deepak

    2014-01-01

    Radiation proctopathy is a complication of pelvic radiotherapy, which occurs in patients treated for carcinoma of the prostate, rectum, urinary bladder, cervix, uterus, and testes. If it presents within 6 weeks to 9 months after therapy, it is called acute radiation proctitis/proctopathy (ARP), and if it occurs 9 months to a year after treatment, it is classified as chronic radiation proctitis/proctopathy (CRP). CRP occurs in 5%–20% of patients receiving pelvic radiation, depending on the radiation dose and the presence or absence of chemotherapy. In many cases, CRP resolves spontaneously, but in some, it can lead to persistent rectal bleeding. Other symptoms of CRP include diarrhea, mucoid discharge, urgency, tenesmus, rectal pain, and fecal incontinence. Despite the availability of several therapies, many patients fail to respond, and continue to suffer in their quality of life. Radiofrequency ablation (RFA) is a newer endoscopic technique that uses radiofrequency energy to ablate tissue. This is an emerging way to treat radiation proctopathy and other mucosal telangiectasia. We present three cases of radiation proctopathy treated with RFA at our institute and review the literature on treatment modalities for CRP. We were also able to find 16 other cases of CRP that used RFA, and review their literature as well as literature on other treatment modalities. PMID:25525377

  12. [Pneumothorax during laparoscopic percutaneous transthoracic radiofrequency ablation for liver tumors of the hepatic dome: a case report].

    PubMed

    Abe, Eiji; Abe, Mari

    2007-10-01

    A 69-year-old man with hepatoma was scheduled for laparoscopic percutaneous transthoracic radiofrequency ablation (RFA) under general anesthesia. His history and physical examination were unremarkable. Anesthesia was induced with propofol and maintained with oxygen-air, sevoflurane and fentanyl. After pneumoperitoneum was introduced, percutaneous RFA needle was inserted into the hepatoma crossing the thoracic cavity and diaphragm several times. Sixty-five minutes after the start of pneumoperitoneum, breathing sounds gradually decreased over the right side of the chest. Because his oxygenation and hemodynamics were stable, the operation was continued with pneumoperitoneum. At the end of surgery, breathing sounds were hardly audible over the right side of the chest. Postoperative chest X-ray showed right pneumothorax. Following thoracentesis, the patient was successfully extubated. During laparoscopic percutaneous transthoracic radiofrequency ablation for liver tumors in the hepatic dome, pneumothorax can occur easily due to passage of peritoneal gas through lesion of the diaphragm caused by RFA needle. We anesthesiologist should recognize the risk of this operation.

  13. The role of radiofrequency ablation for treatment of metachronous isolated hepatic metastasis from colorectal cancer.

    PubMed

    Lee, Byoung Chul; Lee, Hyun Gu; Park, In Ja; Kim, So Yeon; Kim, Ki-Hun; Lee, Jae Hoon; Kim, Chan Wook; Lee, Jong Lyul; Yoon, Yong Sik; Lim, Seok-Byung; Yu, Chang Sik; Kim, Jin Cheon

    2016-09-01

    We investigated recurrence pattern and oncologic outcomes after treatment of metachronous isolated liver metastases from colorectal cancer according to treatment modality.We retrospectively analyzed 123 patients treated with hepatic resection and 82 patients treated with radiofrequency ablation (RFA) for metachronous isolated hepatic metastasis from colorectal cancer (HMCRC). We compared clinicopathological data, recurrence pattern, and recurrence-free survival (RFS) rates after the treatment of hepatic metastasis between patients treated with RFA and resection.The patients in the 2 groups were similar in gender, location of primary tumor, disease-free interval to hepatic metastasis, pathologic stage of primary tumor, and number of hepatic metastasis. The age was older in RFA group but it was not statistically different. The mean diameter of the largest hepatic mass was greater in the resection group than in the RFA group (3.1 vs 1.9 cm, P < 0.001). Chemotherapy after the treatment of hepatic metastasis was more commonly given in hepatic resection group (76.4% vs 62.2%, P = 0.04). Recurrence after the treatment of hepatic metastasis was not significantly different between the 2 groups (54.5% vs 65.9% in the resection and RFA groups). However, intrahepatic recurrence without extra-hepatic metastases was more common in the RFA group than in the resection group (47.5% vs 12.1%, P < 0.001). The RFS rate after the treatment of hepatic metastasis was significantly higher in resection group (48.6% vs 33.7%, P = 0.015). The size and number of hepatic metastasis, primary tumor stage, disease-free interval to hepatic metastasis, and the modality of treatment (RFA vs resection) for hepatic metastasis were confirmed as associated factors with re-recurrence after the treatment of hepatic metastasis. Among patients with solitary hepatic metastases of ≤3 cm, marginal recurrence was higher in the RFA group (3% vs 17.2%) and re-RFA was performed to achieve comparable

  14. 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

  15. 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

  16. Systemic siRNA Nanoparticle-Based Drugs Combined with Radiofrequency Ablation for Cancer Therapy

    PubMed Central

    Ahmed, Muneeb; Kumar, Gaurav; Navarro, Gemma; Wang, Yuanguo; Gourevitch, Svetlana; Moussa, Marwan H.; Rozenblum, Nir; Levchenko, Tatyana; Galun, Eithan; Torchilin, Vladimir P.; Goldberg, S. Nahum

    2015-01-01

    Purpose Radiofrequency thermal ablation (RFA) of hepatic and renal tumors can be accompanied by non-desired tumorigenesis in residual, untreated tumor. Here, we studied the use of micelle-encapsulated siRNA to suppress IL-6-mediated local and systemic secondary effects of RFA. Methods We compared standardized hepatic or renal RFA (laparotomy, 1 cm active tip at 70±2°C for 5 min) and sham procedures without and with administration of 150nm micelle-like nanoparticle (MNP) anti-IL6 siRNA (DOPE-PEI conjugates, single IP dose 15 min post-RFA, C57Bl mouse:3.5 ug/100ml, Fisher 344 rat: 20ug/200ul), RFA/scrambled siRNA, and RFA/empty MNPs. Outcome measures included: local periablational cellular infiltration (α-SMA+ stellate cells), regional hepatocyte proliferation, serum/tissue IL-6 and VEGF levels at 6-72hr, and distant tumor growth, tumor proliferation (Ki-67) and microvascular density (MVD, CD34) in subcutaneous R3230 and MATBIII breast adenocarcinoma models at 7 days. Results For liver RFA, adjuvant MNP anti-IL6 siRNA reduced RFA-induced increases in tissue IL-6 levels, α-SMA+ stellate cell infiltration, and regional hepatocyte proliferation to baseline (p<0.04, all comparisons). Moreover, adjuvant MNP anti-IL6- siRNA suppressed increased distant tumor growth and Ki-67 observed in R3230 and MATBIII tumors post hepatic RFA (p<0.01). Anti-IL6 siRNA also reduced RFA-induced elevation in VEGF and tumor MVD (p<0.01). Likewise, renal RFA-induced increases in serum IL-6 levels and distant R3230 tumor growth was suppressed with anti-IL6 siRNA (p<0.01). Conclusions Adjuvant nanoparticle-encapsulated siRNA against IL-6 can be used to modulate local and regional effects of hepatic RFA to block potential unwanted pro-oncogenic effects of hepatic or renal RFA on distant tumor. PMID:26154425

  17. 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

  18. Role of Contrast Enhanced Ultrasound in Radiofrequency Ablation of Metastatic Liver Carcinoma

    PubMed Central

    Wu, Jin-yu; Yang, Wei; Lin, Shu-zhi; Wu, Wei; Yin, Shan-shan; Zhang, Hui; Yan, Kun

    2012-01-01

    Objective To investigate the application of contrast enhanced ultrasound (CEUS) in planning and guiding for radiofrequency ablation (RFA) for metastatic liver carcinoma (MLC). Methods One hundred and thirty-five patients with clinically and pathologically diagnosed MLC (from gastrointestinal tumors) were included in the present study, and 104 of them had received CEUS prior to RFA to assess the number, size, shape, infiltration, location and enhancing features of the lesions. Among the 104 patients, 21 (20.1%) were excluded from RFA treatment due to too many lesions or large infiltrative range based on CEUS. The remaining 83 patients with 147 lesions underwent RFA (group A). During the same period, other 31 patients with 102 lesions serving as control group were treated based on findings of conventional ultrasound without contrast (group B). The patients underwent follow-up enhanced CT at the 1st month, and then every 3–6 months after RFA. The tumor was considered as early necrosis if no contrast enhancement was detected in the treated area on the CT scan at the 1st month. Results In group A, 72 of 147 MLC lesions (48.9%) showed increased sizes on CEUS. Among them, 48 lesions (66.6%) appeared enlarged in arterial phase, and 24 (33.3%) showed enlarged hypoechoic area in parenchymal phase. CEUS showed total 61 additional lesions in 35 patients (42.1%) (ranged from 8 to 15 mm) compared with conventional ultrasound (US), and 42 (68.8%) of them were visualized in parenchymal phase only. There were total 208 lesions in group A underwent RFA with CEUS planning, and the tumor necrosis rate was 94.2% (196/208). In this group, local recurrence was found in 16 lesions (7.7%) during 3–42 months’ following up, and new metastases were seen in 30 cases (36.1%). For group B, the tumor necrosis rate was 86.3% (88/102), local recurrence in 17 lesions (16.7%), and new metastases in 13 cases (41.9%). Tumor early necrosis and recurrence rates were significantly different between

  19. 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

  20. 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

  1. 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.

  2. Characterization of tissue response to radiofrequency ablation using 3D model-based analysis of interventional MR images

    NASA Astrophysics Data System (ADS)

    Weinberg, Brent D.; Lazebnik, Roee S.; Breen, Michael S.; Lewin, Jonathan S.; Wilson, David L.

    2003-05-01

    Using magnetic resonance imaging (MRI), real-time guidance is feasible for radiofrequency (RF) current ablation of pathologic tissue. Lesions have a characteristic two-zone appearance: an inner core (Zone I) surrounded by a hyper-intense rim (Zone II). A better understanding of both the immediate (hyper-acute) and delayed (sub-acute) physiological response of the target tissue will aid development of minimally invasive tumor treatment strategies. We performed in vivo RF ablations in a rabbit thigh model and characterized the tissue response to treatment through contrast enhanced (CE) T1 and T2 weighted MR images at two time points. We measured zonal grayscale changes as well as zone volume changes using a 3D computationally fitted globally deformable parametric model. Comparison over time demonstrated an increase in the volume of both the inner necrotic core (mean 56.5% increase) and outer rim (mean 16.8% increase) of the lesion. Additionally, T2 images of the lesion exhibited contrast greater than or equal to CE T1 (mean 35% improvement). This work establishes a foundation for the clinical use of T2 MR images coupled with a geometric model of the ablation for noninvasive lesion monitoring and characterization.

  3. Interactive MRI-guided radiofrequency interstitial thermal ablation of abdominal tumors: clinical trial for evaluation of safety and feasibility.

    PubMed

    Lewin, J S; Connell, C F; Duerk, J L; Chung, Y C; Clampitt, M E; Spisak, J; Gazelle, G S; Haaga, J R

    1998-01-01

    This clinical trial was performed to evaluate the safety and feasibility of interactive MR-guided radiofrequency (RF) interstitial thermal ablation (ITA) performed entirely within the MR imager. RF-ITA was performed on 11 intra-abdominal metastatic tumors during 13 sessions. The RF electrode was placed under MR guidance on a .2-T system using rapid fast imaging with steady state precession (FISP) and true FISP images. A custom 17-gauge electrode was used and was modified in four sessions to allow circulation of iced saline for cooling during ablation. Tissue necrosis monitoring and electrode repositioning were based on rapid T2-weighted and short-inversion-time inversion recovery (STIR) sequences. Morbidity and toxicity were assessed by clinical and imaging criteria. The region of tissue destruction was visible in all 11 tumors treated, as confirmed on subsequent contrast-enhanced images. No significant morbidity was noted, and patient discomfort was minimal. In conclusion, interactive MR-guided RF-ITA is feasible on a clinical .2-T C-arm system with supplemental interventional accessories with only minor patient morbidity. The ability to completely ablate tumors with RF-ITA depends on tumor size and vascularity. PMID:9500259

  4. 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

  5. An ex vivo study on radiofrequency tissue ablation: increased lesion size by using an "expandable-wet" electrode.

    PubMed

    Miao, Y; Ni, Y; Yu, J; Zhang, H; Baert, A; Marchal, G

    2001-01-01

    The present comparative study was conducted to validate a newly developed "expandable-wet" electrode for an increased lesion size of radiofrequency ablation (RFA) on excised beef liver. The expandable-wet electrode, which allows interstitial hypertonic saline infusion through retractable curved needles, was compared with "expanded-dry" and "unexpanded-wet" electrodes for RFA lesion size and other parameters. A total of 120 lesions were created under 50 W (groups A-C) and 90 W (groups A'-C') power control mode for 10 min at each ablation site with the following groups: group A and A' of expanded-dry electrode (needles deployed but saline uninfused); group B and B' of unexpanded-wet electrode (saline infused but needle undeployed); and group C and C' of expanded-wet electrode (needles deployed and saline infused). Together with lower impedance and higher power output, the lesion size in group C (5.3+/-0.4 cm) and C' (6.0+/-1.0 cm) were significantly larger (P<0.01) than that in group A (3.3+/-0.3 cm) and A' (2.0+/-0.2 cm), and group B (3.8+/-1.0 cm) and B' (2.6+/-0.4 cm). The RFA lesion size can be significantly enlarged when the expandable electrode is complemented with interstitial hypertonic saline infusion. This design may improve the efficacy of RF tumor ablation.

  6. 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

  7. 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.

  8. 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

  9. 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

  10. Image-Guided Radiofrequency Ablation (RFA) of Unresectable Hepatic Tumors Using a Triple-Spiral-Shaped Electrode Needle: Initial Experience in 34 Patients

    SciTech Connect

    Thanos, Loukas; Poulou, Loukia S.; Ziakas, Panayiotis D.; Kelekis, Alexis D.; Pomoni, Maria; Kelekis, Dimitrios A.

    2010-02-15

    We evaluated the safety and efficacy of image-guided radiofrequency ablation (RFA) using a triple-spiral-shaped electrode needle for unresectable primary or metastatic hepatic tumors. Thirty-four patients with 46 index tumors were treated. Ablation zone, morbidity, and complications were assessed. The lesions were completely ablated with an ablative margin of about 1 cm. Five patients (14.7%) with a lesion larger than 4.5 cm had local tumor progression after 1 month and were retreated. Hemothorax, as a major complication, occurred in 1 of 34 patients (3.0%) or 1 of 46 lesions ablated (2.2%). RFA using this new electrode needle can be effective in the treatment of large unresectable hepatic tumors.

  11. 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

  12. Sorafenib combined with radiofrequency ablation in the treatment of a patient with renal cell carcinoma plus primary hepatocellular carcinoma.

    PubMed

    Gang, Guo; Hongkai, Yu; Xu, Zhang

    2015-01-01

    The combination of renal cell carcinoma (RCC) and hepatocellular carcinoma (HCC) is extremely rare, and the prognosis for patients with these two cancers is poor. In the past decade, molecular targeted therapy and radiofrequency ablation (RFA) have emerged and these treatments are now playing an increasingly important role in the management of patients with advanced primary RCC and HCC. In this case report, a 72-year-old male patient diagnosed as having RCC invading the renal vein and grade I-II HCC was treated with RFA and sorafenib (400 mg twice daily). After 3 months of this combination treatment, an evaluation of his target lesions showed stable disease (SD), and progression-free survival (PFS) times were 28 months weeks for RCC and 16 months weeks for HCC. Overall survival (OS) was 40 weeks. PMID:26881596

  13. Sorafenib combined with radiofrequency ablation in the treatment of a patient with renal cell carcinoma plus primary hepatocellular carcinoma.

    PubMed

    Gang, Guo; Hongkai, Yu; Xu, Zhang

    2015-01-01

    The combination of renal cell carcinoma (RCC) and hepatocellular carcinoma (HCC) is extremely rare, and the prognosis for patients with these two cancers is poor. In the past decade, molecular targeted therapy and radiofrequency ablation (RFA) have emerged and these treatments are now playing an increasingly important role in the management of patients with advanced primary RCC and HCC. In this case report, a 72-year-old male patient diagnosed as having RCC invading the renal vein and grade I-II HCC was treated with RFA and sorafenib (400 mg twice daily). After 3 months of this combination treatment, an evaluation of his target lesions showed stable disease (SD), and progression-free survival (PFS) times were 28 months weeks for RCC and 16 months weeks for HCC. Overall survival (OS) was 40 weeks.

  14. Ultrasound-guided pulsed radiofrequency ablation of the genital branch of the genitofemoral nerve for treatment of intractable orchalgia

    PubMed Central

    Terkawi, Abdullah Sulieman; Romdhane, Kamel

    2014-01-01

    Chronic orchalgia is a frustrating clinical problem for both the patient and the physician. We present a 17-year-old boy with a bilateral idiopathic chronic intractable orchalgia with failed conservative treatment. For 2 years, he suffered from severe attacks of scrotal pain that affected his daily activities and caused frequent absence from school. Ultrasound-guided pulsed radiofrequency ablation (PRF) of the genital branches of the genitofemoral nerve performed after local anesthetic nerve block confirmed the diagnosis and yielded 6 weeks of symptom relief. Seven-month follow-up revealed complete satisfactory analgesia. The use of PRF is an effective and non-invasive approach to treat intractable chronic orchalgia. PMID:24843352

  15. 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

  16. Sacro-Iliac Joint Sensory Block and Radiofrequency Ablation: Assessment of Bony Landmarks Relevant for Image-Guided Procedures

    PubMed Central

    Roberts, Shannon L.; Burnham, Robert S.; Loh, Eldon; Agur, Anne M.

    2016-01-01

    Image-guided sensory block and radiofrequency ablation of the nerves innervating the sacro-iliac joint require readily identifiable bony landmarks for accurate needle/electrode placement. Understanding the relative locations of the transverse sacral tubercles along the lateral sacral crest is important for ultrasound guidance, as they demarcate the position of the posterior sacral network (S1–S3 ± L5/S4) innervating the posterior sacro-iliac joint. No studies were found that investigated the spatial relationships of these bony landmarks. The purpose of this study was to visualize and quantify the interrelationships of the transverse sacral tubercles and posterior sacral foramina to inform image-guided block and radiofrequency ablation of the sacro-iliac joint. The posterior and lateral surfaces of 30 dry sacra (15 M/15 F) were digitized and modeled in 3D and the distances between bony landmarks quantified. The relationships of bony landmarks (S1–S4) were not uniform. The mean intertubercular and interforaminal distances decreased from S1 to S4, whereas the distance from the lateral margin of the posterior sacral foramina to the transverse sacral tubercles increased from S1 to S3. The mean intertubercular distance from S1 to S3 was significantly (p < 0.05) larger in males. The interrelationships of the sacral bony landmarks should be taken into consideration when estimating the site and length of an image-guided strip lesion targeting the posterior sacral network. PMID:27747222

  17. 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

  18. 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

  19. 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

  20. Radiofrequency catheter ablation: different cooled and noncooled electrode systems induce specific lesion geometries and adverse effects profiles.

    PubMed

    Dorwarth, Uwe; Fiek, Michael; Remp, Thomas; Reithmann, Cristopher; Dugas, Martin; Steinbeck, Gerhard; Hoffmann, Ellen

    2003-07-01

    The success and safety of standard catheter radiofrequency ablation may be limited for ablation of atrial fibrillation and ventricular tachycardia. The aim of this study was to characterize and compare different cooled and noncooled catheter systems in terms of their specific lesion geometry, incidence of impedance rise, and crater and coagulum formation to facilitate appropriate catheter selection for special indications. The study investigated myocardial lesion generation of three cooled catheter systems (7 Fr, 4-mm tip): two saline irrigation catheters with a showerhead-type electrode tip (sprinkler) and a porous metal tip and an internally cooled catheter. Noncooled catheters (7 Fr) had a large tip electrode (8 mm) and a standard tip electrode (4 mm). RF energy was delivered on isolated porcine myocardium superfused with heparinized pig blood (37 degrees C) at power settings of 10-40 W. Both irrigated systems were characterized by a large lesion depth (8.1 +/- 1.6 mm) and a large lesion diameter (13.8 +/- 1.6 mm). In comparison, internally cooled lesions showed a similar lesion depth (8.0 +/- 1.0 mm), but a significantly smaller lesion diameter (12.3 +/- 1.2 mm,P = 0.04). Large tip lesions had a similar lesion diameter (14.5 +/- 1.6 mm), but a significantly smaller lesion depth (6.3 +/- 1.0 mm,P = 0.002) compared to irrigated lesions. However, lesion volume was not significantly different between the three cooled and the large tip catheter. To induce maximum lesion size, power requirements were three times higher for the irrigation systems and two times higher for the internally cooled and the large tip catheter compared to the standard catheter. Impedance rise was rarest with irrigated and large tip ablation. In case of impedance rise crater formation was a frequent observation (61-93%). Irrigated catheters prevented coagulum formation most effectively. Irrigated rather than internally cooled ablation appears to be most adequate for the induction of deep and

  1. 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.

  2. 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.

  3. Intracardiac Acoustic Radiation Force Impulse Imaging: A Novel Imaging Method for Intraprocedural Evaluation of Radiofrequency Ablation Lesions

    PubMed Central

    Eyerly, Stephanie A.; Bahnson, Tristram D.; Koontz, Jason I.; Bradway, David P.; Dumont, Douglas M.; Trahey, Gregg E.; Wolf, Patrick D.

    2012-01-01

    Background Arrhythmia recurrence after cardiac radiofrequency ablation (RFA) for atrial fibrillation (AF) has been linked to conduction through discontinuous lesion lines. Intraprocedural visualization and corrective ablation of lesion line discontinuities could decrease post-procedure AF recurrence. Intracardiac acoustic radiation force impulse (ARFI) imaging is a new imaging technique that visualizes RFA lesions by mapping the relative elasticity contrast between compliant-unablated and stiff-RFA treated myocardium. Objective To determine if intraprocedure ARFI images can identify RFA treated myocardium in vivo. Methods In eight canines, an electroanatomical mapping (EAM) guided intracardiac echo catheter (ICE) was used to acquire 2D ARFI images along right atrial ablation lines before and after RFA. ARFI images were acquired during diastole with the myocardium positioned at the ARFI focus (1.5 cm) and parallel to the ICE transducer for maximal and uniform energy delivery to the tissue. Three reviewers categorized each ARFI image as depicting no lesion, non-contiguous, or contiguous lesion. For comparison, three separate reviewers confirmed RFA lesion presence and contiguity based on functional conduction block at the imaging plane location on EAM activation maps. Results Ten percent of ARFI images were discarded due to motion artifacts. Reviewers of the ARFI images detected RFA-treated sites with high sensitivity (95.7%) and specificity (91.5%). Reviewer identification of contiguous lesion had 75.3% specificity and 47.1% sensitivity. Conclusions Intracardiac ARFI imaging was successful in identifying endocardial RFA treatment when specific imaging conditions were maintained. Further advances in ARFI imaging technology would facilitate a wider range of imaging opportunities for clinical lesion evaluation. PMID:22772134

  4. 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.

  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. Real-time conductivity imaging of temperature and tissue property changes during radiofrequency ablation: an ex vivo model using weighted frequency difference.

    PubMed

    Wi, Hun; McEwan, Alistair Lee; Lam, Vincent; Kim, Hyung Joong; Woo, Eung Je; Oh, Tong In

    2015-04-01

    We demonstrated the feasibility of time difference and weighted frequency difference conductivity imaging for real-time monitoring of temperature distribution and ablation region estimation during radiofrequency (RF) ablation. The electrical conductivity spectrum of biological tissue reflects mobility of ions in intra- and extra-cellular fluids and changes in cellular morphology induced by heating. The time series conductivity spectra were measured in an ex vivo bovine liver by a high-speed electrical impedance tomography (EIT) system. The EIT system was protected by filters to suppress RF energy and allow interleaved real-time imaging. We recorded time and weighted frequency-difference conductivity images and direct temperature variations at the ablation region and control region during 8 min ablation and for the following 66 min of cooling. Conductivity variation in regions of interest was compared with temperature recordings. Contours of conductivity change were visualized and compared to estimate the ablation area. EIT images confirmed increase of conductivity at all frequencies and loss of frequency conductivity change associated with loss of cellular structure. Time difference conductivity images showed changes due to both heating during ablation and heat dissipation following ablation together with tissue property changes. Weighted frequency-difference images presented persistent changes following heating due to the morphological change in the ablation zone.

  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. Acute Safety of an Open-Irrigated Ablation Catheter with 56-Hole Porous Tip for Radiofrequency Ablation of Paroxysmal Atrial Fibrillation: Analysis from 2 Observational Registry Studies

    PubMed Central

    OZA, SAUMIL R; HUNTER, TINA D; BIVIANO, ANGELO B; DANDAMUDI, GOPI; HERWEG, BENGT; PATEL, ANSHUL M; POLLAK, SCOTT J; WANG, HUIJIAN; FISHEL, ROBERT S

    2014-01-01

    Acute Safety from 2 AF Ablation Registries Introduction This report presents safety data on the use of a new open-irrigation radiofrequency ablation (RFA) catheter with a 56-hole porous tip in 742 patients enrolled in 2 US prospective, multicenter observational registry studies representing real-world use of the catheter. Methods This analysis is comprised of patients who underwent RFA of drug-refractory recurrent symptomatic paroxysmal atrial fibrillation (AF). Acute adverse events (AEs) were collected and categorized by seriousness, timing, and relatedness, with 7 days of follow-up data in one study and at least 120 days of data from a 1-year follow-up in the other. Acute serious adverse events (SAEs) that were identified as potentially related to the device and/or procedure were adjudicated by an independent safety committee. Results A total of 30 patients (4.0%) in the combined studies experienced an acute SAE related to the device and/or procedure, which was similar in the subset of patients age 65 and over (4.2%). These SAEs included 1.2% cardiac tamponade/perforation, 0.7% pericarditis, 0.5% pulmonary events, and 0.8% vascular access complications. No myocardial infarction, stroke, transient ischemic attack, or atrioesophageal fistulas within 7 days postprocedure were reported. In the study with extended follow-up, 1 pulmonary vein stenosis and 1 esophageal injury were seen beyond 7 days postprocedure (0.2% each). There were no device or procedure related deaths. Conclusion Results from 2 large observational studies demonstrated that a new porous tip RFA catheter was safe for the treatment of drug refractory, recurrent, symptomatic paroxysmal AF, including treatment of older patients (≥65 years). PMID:24602038

  9. Pulmonary Thromboembolism Following Radio-Frequency Ablation of the Atrioventricular Node in a Patient Heterozygous for the Factor V Leiden and the Mthfr C677T Mutations

    PubMed Central

    Pešut, DP; Raljević, SV; Kontić, MDj; Božić, DZ; Buha, IB; Stević, RS

    2011-01-01

    Patients who undergo radiofrequency ablation of the atrioventricular (AV) node rarely develop acute major complications. A 41-year-old Caucasian male smoker, was admitted to the Pulmology Teaching Hospital at Belgrade, Serbia, for sharp persistent chest pain, fever and fatigue following AV node radiofrequency ablation for arrhythmia. Chest X-ray showed obtuse right costo-phrenic angle and laminar atelectasis in the right lower lung lobe. The plasma D-dimer level was elevated. A perfusion lung scan showed multiple bilateral perfusion defects and multislice computed tomography showed thrombotic mass in the right pulmonary artery. Genetic analysis revealed that he was heterozygous for the prothrombin Factor V (FV) Leiden and MTHFR C677T mutations. Therapy started with intravenous heparin, followed by warfarin. He had no other episodes over a 2-year follow-up. Lifelong oral anticoagulant therapy was recommended. PMID:24052703

  10. 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.

  11. Contact Geometry Affects Lesion Formation in Radio-Frequency Cardiac Catheter Ablation

    PubMed Central

    Gallagher, Neal; Fear, Elise C.; Byrd, Israel A.; Vigmond, Edward J.

    2013-01-01

    One factor which may be important for determining proper lesion creation during atrial ablation is catheter-endocardial contact. Little information is available that relates geometric contact, depth and angle, to ablation lesion formation. We present an electrothermal computer model of ablation that calculated lesion volume and temperature development over time. The Pennes bioheat equation was coupled to a quasistatic electrical problem to investigate the effect of catheter penetration depth, as well as incident catheter angle as may occur in practice. Biological experiments were performed to verify the modelling of electrical phenomena. Results show that for deeply penetrating tips, acute catheter angles reduced the rate of temperature buildup, allowing larger lesions to form before temperatures elevated excessively. It was also found that greater penetration did not lead to greater transmurality of lesions. We conclude that catheter contact angle plays a significant role in lesion formation, and the time course must be considered. This is clinically relevant because proper identification and prediction of geometric contact variables could improve ablation efficacy. PMID:24086275

  12. Transcatheter patent foramen ovale closure and radiofrequency ablation of right atrial tachycardia.

    PubMed

    Manola, Šime; Bernat, Robert; Pavlović, Nikola; Radeljić, Vjekoslav; Bulj, Nikola; Trbušić, Matias

    2014-12-01

    Patent foramen ovale (PFO) can be found in approximately 25% of adult population. Transcatheter closure of PFO is a potential option in selected patients with PFO. We report a case of a female patient that underwent mapping and catheter ablation of atrial tachycardia and PFO closure in the same procedure.

  13. 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

  14. Long-term follow-up in sacroiliac joint pain patients treated with radiofrequency ablative therapy.

    PubMed

    Romero, Flávio Ramalho; Vital, Roberto Bezerra; Zanini, Marco Antônio; Ducati, Luis Gustavo; Gabarra, Roberto Colichio

    2015-06-01

    Sacroiliac joint (SIJ) pain is responsible for up to 40% of all cases of lumbar back pain. Objective Report the long-term efficacy of radiofrequency denervation for sacroiliac joint pain at six, twelve and eighteen months.Method Third-two adults' patients with sacroiliac join pain diagnosis were included for a prospective study. Primary outcome measure was pain intensity on the Numeric Rating Scale (NRS). Secondary outcome measure was Patient Global Impression of Change Scale (PGIC).Results Short-term pain relief was observed, with the mean NRS pain score decreasing from 7.7 ± 1.8 at baseline to 2.8 ± 1.2 at one month and to 3.1 ± 1.9 at six months post-procedure (p < 0.001). Long-term pain relief was sustained at twelve and eighteen months post-procedure, with NRS pain remaining at 3.4 ± 2.1 and 4.0 ± 2.7, respectively.Conclusion Radiofrequency denervation of the SIJ can significantly reduce pain in selected patients with sacroiliac syndrome.

  15. [Electroanatomical mapping and radiofrequency ablation of tachycardia originating in pulmonary vein in an adult patient].

    PubMed

    Végh, Eszter Mária; Széplaki, Gábor; Szilágyi, Szabolcs; Osztheimer, István; Tahin, Tamás; Merkely, Béla; Gellér, László

    2011-08-21

    A 29-year-old male was admitted to our outpatient clinic because of palpitation and documented narrow QRS arrhythmia. Based on the ECG, supraventricular tachycardia was diagnosed, electrophysiological examination was indicated and ablation therapy was recommended. During positioning of the catheter the patient developed arrhythmia. On the coronary sinus catheter the activation spread from distal to proximal electrodes, suggesting left atrial origin. During atrial entrainment pacing long return cycle was observed and distal coronary sinus pacing resulted in a 15 ms longer cycle length than the arrhythmia. Therefore, the left atrial origin of the arrhythmia was confirmed and double transseptal puncture was performed. Lasso and irrigated tip catheter were introduced into the left atrium and electroanatomical mapping was performed with CARTO3 system. After electroanatomical mapping the origin of tachycardia was located proximally in the left superior pulmonary vein. Ablation was started at the earliest activation point, where acceleration was observed and the arrhythmia stopped after the first ablation. Pulmonary vein isolation was completed, and bidirectional block could be confirmed. After 30 minutes the arrhythmia was not inducible. During follow-up, Holter-examination was negative and the patient remained asymptomatic. The pulmonary vein tachycardia is a supraventricular arrhythmia that can occur at any age, but the diagnosis based on the ECG is not always simple. Detailed electroanatomical mapping is very important in the diagnosis of this type of arrhythmia, although it can be verified with conventional electrophysiological methods as well. Focal ablation may be a therapeutic option; however, total isolation of pulmonary veins can be more effective. PMID:21835744

  16. [Electroanatomical mapping and radiofrequency ablation of tachycardia originating in pulmonary vein in an adult patient].

    PubMed

    Végh, Eszter Mária; Széplaki, Gábor; Szilágyi, Szabolcs; Osztheimer, István; Tahin, Tamás; Merkely, Béla; Gellér, László

    2011-08-21

    A 29-year-old male was admitted to our outpatient clinic because of palpitation and documented narrow QRS arrhythmia. Based on the ECG, supraventricular tachycardia was diagnosed, electrophysiological examination was indicated and ablation therapy was recommended. During positioning of the catheter the patient developed arrhythmia. On the coronary sinus catheter the activation spread from distal to proximal electrodes, suggesting left atrial origin. During atrial entrainment pacing long return cycle was observed and distal coronary sinus pacing resulted in a 15 ms longer cycle length than the arrhythmia. Therefore, the left atrial origin of the arrhythmia was confirmed and double transseptal puncture was performed. Lasso and irrigated tip catheter were introduced into the left atrium and electroanatomical mapping was performed with CARTO3 system. After electroanatomical mapping the origin of tachycardia was located proximally in the left superior pulmonary vein. Ablation was started at the earliest activation point, where acceleration was observed and the arrhythmia stopped after the first ablation. Pulmonary vein isolation was completed, and bidirectional block could be confirmed. After 30 minutes the arrhythmia was not inducible. During follow-up, Holter-examination was negative and the patient remained asymptomatic. The pulmonary vein tachycardia is a supraventricular arrhythmia that can occur at any age, but the diagnosis based on the ECG is not always simple. Detailed electroanatomical mapping is very important in the diagnosis of this type of arrhythmia, although it can be verified with conventional electrophysiological methods as well. Focal ablation may be a therapeutic option; however, total isolation of pulmonary veins can be more effective.

  17. 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.

  18. CT-Guided Percutaneous Step-by-Step Radiofrequency Ablation for the Treatment of Carcinoma in the Caudate Lobe.

    PubMed

    Dong, Jun; Li, Wang; Zeng, Qi; Li, Sheng; Gong, Xiao; Shen, Lujun; Mao, Siyue; Dong, Annan; Wu, Peihong

    2015-09-01

    The location of the caudate lobe and its complex anatomy make caudate lobectomy and radiofrequency ablation (RFA) under ultrasound guidance technically challenging. The objective of the exploratory study was to introduce a novel modality of treatment of lesions in caudate lobe and discuss all details with our experiences to make this novel treatment modality repeatable and educational. The study enrolled 39 patients with liver caudate lobe tumor first diagnosed by computerized tomography (CT) or magnetic resonance imaging (MRI). After consultation of multi-disciplinary team, 7 patients with hepatic caudate lobe lesions were enrolled and accepted CT-guided percutaneous step-by-step RFA treatment. A total of 8 caudate lobe lesions of the 7 patients were treated by RFA in 6 cases and RFA combined with percutaneous ethanol injection (PEI) in 1 case. Median tumor diameter was 29 mm (range, 18-69 mm). A right approach was selected for 6 patients and a dorsal approach for 1 patient. Median operative time was 64 min (range, 59-102 min). Median blood loss was 10 mL (range, 8-16 mL) and mainly due to puncture injury. Median hospitalization time was 4 days (range, 2-5 days). All lesions were completely ablated (8/8; 100%) and no recurrence at the site of previous RFA was observed during median 8 months follow-up (range 3-11 months). No major or life-threatening complications or deaths occurred. In conclusion, percutaneous step-by-step RFA under CT guidance is a novel and effective minimally invasive therapy for hepatic caudate lobe lesions with well repeatability.

  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. 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.

  1. 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.

  2. Outcomes from a prospective trial of endoscopic radiofrequency ablation of early squamous cell neoplasia of the esophagus

    PubMed Central

    Bergman, Jacques JGHM; Zhang, Yueming; He, Shun; Weusten, Bas; Xue, Liyan; Fleischer, David E; Lu, Ning; Dawsey, Sanford M; Wang, Gui-Qi

    2012-01-01

    Background Radiofrequency ablation (RFA) is safe and effective for eradicating neoplasia in Barrett’s esophagus. Objective Evaluate RFA for eradicating early esophageal squamous cell neoplasia (ESCN) defined as moderate- and high-grade squamous intraepithelial neoplasia (MGIN, HGIN) and early flat-type esophageal squamous cell carcinoma (ESCC). Design Prospective cohort study. Setting Tertiary referral center. Patients Esophageal unstained lesions (USLs) were identified using Lugol’s chromoendoscopy. Inclusion: at least 1 flat (type 0-IIb) USL ≥3cm, USL-bearing esophagus ≤12 cm, and a consensus diagnosis of MGIN, HGIN, or ESCC by two expert GI pathologists. Exclusion: prior endoscopic resection or ablation, stricture, or any non-flat mucosa. Interventions Circumferential RFA creating a continuous treatment area (TA) including all USLs. At 3-month intervals thereafter, chromoendoscopy with biopsies, followed by focal RFA of USLs, if present. Main outcome measures Complete response (CR) at 12 months, defined as absence of MGIN, HGIN or ESCC in TA; CR after one RFA session; neoplastic progression from baseline; and adverse events. Results 29 patients (14 male, mean age 60.3 years) with MGIN (18), HGIN (10), or ESCC (1) participated. Mean USL length was 6.2 cm (TA 8.2 cm). At 3-months, after one RFA session, 86% of patients (25/29) were CR. At 12-months, 97% (28/29) of patients were CR. There was no neoplastic progression. There were 4 strictures, all dilated to resolution. Limitations Single center study with limited number of patients. Conclusions In patients with early ESCN (MGIN, HGIN, flat-type ESCC), RFA was associated with a high rate of histological complete response (97% of patients), no neoplastic progression, and an acceptable adverse event profile. PMID:21839994

  3. 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

  4. Radiofrequency Ablation with a New Perfused-Cooled Electrode Using a Single Pump: An Experimental Study in Ex Vivo Bovine Liver

    SciTech Connect

    Kim, Seung Kwon Seo, Jung Wook

    2005-12-15

    The purpose of this study was to assess the efficacy of a new perfused-cooled electrode that uses a single pump for creating a large ablation zone in explanted bovine liver. This was done by comparing with the radiofrequency (RF) ablation zones that were created with a monopolar cooled electrode to the RF ablation zones that were created by the new perfused-cooled electrode. We developed a new perfused-cooled electrode that uses a single pump by modifying a 17-gauge cooled electrode (Radionics) with a 2.5-cm outer metallic sheath (15-gauge) in order to allow use of the internal cooling water (5.85 % hypertonic saline) for the infused saline. Thirty ablation zones were created in explanted bovine livers (12-min ablation cycle; pulsed technique; 2000 mA, maximum) with three different regimens: group A, RF ablation with the 17-gauge cooled electrode; group B, RF ablation with the 15-gauge cooled electrode; group C, RF ablation with the perfused-cooled electrode. T2-weighted magnetic resonance (MR) imaging was obtained immediately after RF ablation for calculating volumes of the ablation zone. Following MR imaging, the ablation zones were excised and measured for transverse diameters and vertical diameters. The transverse diameter, vertical diameter, and the calculated volumes of the ablation zones on MR imaging were compared among the groups. Ablation zones created with the perfused-cooled electrode (group C) were significantly larger than those created with the 17-gauge cooled electrode (group A) and the 15-gauge cooled electrode (group B) according to the transverse diameter and vertical diameter on the gross specimens (p < 0.05): 3.6 {+-} 0.38 cm and 4.4 {+-} 0.20 cm in group A, 3.7 {+-} 0.08 cm and 4.6 {+-} 0.16 cm in group B, and 5.4 {+-} 0.65 cm and 6.0 {+-} 0.56 cm in group C, respectively. On the MR imaging, the calculated volumes of the ablation zones in group C were significantly larger than those in groups A and B (p < 0.05): 23.1 {+-} 8.7 cm{sup 3} in

  5. Bipolar radiofrequency-induced thermotherapy of haemorrhoids: a new minimally invasive method for haemorrhoidal disease treatment. Early results of a pilot study

    PubMed Central

    Duben, Jiri; Hnatek, Lukas; Dudesek, Bohumil; Humpolicek, Petr

    2012-01-01

    Introduction Haemorrhoidal disease is the most frequent benign anorectal disease. Conservative, minimally invasive and surgical methods are used in the treatment of haemorrhoidal disease. Radiofrequency thermoablation is a popular new technique in the treatment of varicose veins. Aim Assessment of the use of the method in the treatment of haemorrhoidal disease using bipolar radiofrequency-induced thermotherapy (RFITT or so-called Celon method). Material and methods We used the CelonLab PRECISION (Celon AG medical instruments, Teltow, Germany) with the bipolar RFITT applicator Celon ProBREATH for the treatment of haemorrhoidal disease stages III and IV. Results In the Department of Surgery at the Atlas Hospital in Zlin, Czech Republic, a total of 71 patients were treated from 9/2007 to 10/2010 with this new treatment approach. The success rate was 100%, local recurrence rate was 2.8%, and medium-term satisfaction of patients who underwent the procedure was 99.5%. Complications appeared in 4.26% of cases. Conclusions The new RFITTH technique for treatment of advanced stages of haemorrhoidal disease is a new treatment modality with good curative response, low level of complications, minimum pain and quick return of patients to their usual activities. PMID:23630553

  6. 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.

  7. 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

  8. 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.

  9. 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

  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. 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

  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. 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

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. Successful radiofrequency ablation of atrial tachycardias in surgically repaired Ebstein's anomaly using the Carto XP system and the QwikStar catheter.

    PubMed

    Drago, Fabrizio; Brancaccio, Gianluca; Grutter, Giorgia; De Santis, Antonella; Fazio, Giovanni; Silvetti, Massimo Stefano

    2007-06-01

    We describe the case of a child with three different atrial tachyarrhythmias originating from the right atrium, in whom a limited modified maze procedure was performed during surgical repair of an Ebstein's anomaly. Successful radiofrequency transcatheter ablation of all atrial tachyarrhythmias, one re-entrant and two focal, was obtained using the Carto XP EP three-dimensional navigation and ablation system, the new QwikMap software technology and the new mapping/ablation QwikStar multipolar catheter. No conventional mapping was used in addition to the three-dimensional system. Total procedural time was about 3 h and fluoroscopy time was 40 min. There were neither recurrences of the tachycardias nor complications during the follow-up (15 months).

  20. Do Liposomal Apoptotic Enhancers Increase Tumor Coagulation and End-Point Survival in Percutaneous Radiofrequency Ablation of Tumors in a Rat Tumor Model? 1

    PubMed Central

    Yang, Wei; Elian, Mostafa; Hady, El-Shymma A.; Levchenko, Tatyana S.; Sawant, Rupa R.; Signoretti, Sabina; Collins, Michael; Torchilin, Vladimir P.; Goldberg, S. Nahum

    2010-01-01

    Purpose: To characterize effects of combining radiofrequency (RF) ablation with proapoptotic intravenous liposome-encapsulated paclitaxel and doxorubicin on tumor destruction, apoptosis and heat-shock protein (HSP) production, intratumoral drug accumulation, and end-point survival. Materials and Methods: R3230 mammary adenocarcinomas (n = 177) were implanted in 174 rats in this animal care committee–approved study. Tumors received (a) no treatment, (b) RF ablation, (c) paclitaxel, (d) RF ablation followed by paclitaxel (RF ablation–paclitaxel), (e) paclitaxel before RF ablation (paclitaxel–RF ablation), (f) RF ablation followed by doxorubicin (RF ablation–doxorubicin), (g) paclitaxel followed by doxorubicin without RF ablation (paclitaxel-doxorubicin), or (h) paclitaxel before RF ablation, followed by doxorubicin (paclitaxel–RF ablation–doxorubicin). Tumor coagulation area and diameter were compared at 24–96 hours after treatment. Intratumoral paclitaxel uptake with and without RF ablation were compared. Immunohistochemical staining revealed cleaved caspase-3 and 70-kDa HSP (HSP70) expression. Tumors were randomized into eight treatment arms for Kaplan-Meier analysis of defined survival end-point (3.0-cm diameter). Results: Paclitaxel–RF ablation increased tumor coagulation over RF ablation or paclitaxel (mean, 14.0 mm ± 0.9 [standard deviation], 6.7 mm ± 0.6, 2.5 mm ± 0.6, respectively; P < .001). Paclitaxel–RF ablation–doxorubicin had similar tumor coagulation (P < .05), compared with paclitaxel–RF ablation, at 24 and 96 hours. Mean intratumoral paclitaxel accumulation for paclitaxel–RF ablation (6.76 μg/g ± 0.35) and RF ablation–paclitaxel (9.28 μg/g ± 0.87) increased over that for paclitaxel (0.63 μg/g ± 0.25, P < .001). Paclitaxel substantially increased apoptosis and decreased HSP70 expression at coagulation margin. Mean end-point survival for paclitaxel–RF ablation–doxorubicin (56.8 days ± 25.3) was greater, compared

  1. Cryoballoon or radiofrequency ablation for symptomatic paroxysmal atrial fibrillation: reintervention, rehospitalization, and quality-of-life outcomes in the FIRE AND ICE trial

    PubMed Central

    Kuck, Karl-Heinz; Fürnkranz, Alexander; Chun, K.R. Julian; Metzner, Andreas; Ouyang, Feifan; Schlüter, Michael; Elvan, Arif; Lim, Hae W.; Kueffer, Fred J.; Arentz, Thomas; Albenque, Jean-Paul; Tondo, Claudio; Kühne, Michael; Sticherling, Christian; Brugada, Josep

    2016-01-01

    Aims The primary safety and efficacy endpoints of the randomized FIRE AND ICE trial have recently demonstrated non-inferiority of cryoballoon vs. radiofrequency current (RFC) catheter ablation in patients with drug-refractory symptomatic paroxysmal atrial fibrillation (AF). The aim of the current study was to assess outcome parameters that are important for the daily clinical management of patients using key secondary analyses. Specifically, reinterventions, rehospitalizations, and quality-of-life were examined in this randomized trial of cryoballoon vs. RFC catheter ablation. Methods and results Patients (374 subjects in the cryoballoon group and 376 subjects in the RFC group) were evaluated in the modified intention-to-treat cohort. After the index ablation, log-rank testing over 1000 days of follow-up demonstrated that there were statistically significant differences in favour of cryoballoon ablation with respect to repeat ablations (11.8% cryoballoon vs. 17.6% RFC; P = 0.03), direct-current cardioversions (3.2% cryoballoon vs. 6.4% RFC; P = 0.04), all-cause rehospitalizations (32.6% cryoballoon vs. 41.5% RFC; P = 0.01), and cardiovascular rehospitalizations (23.8% cryoballoon vs. 35.9% RFC; P < 0.01). There were no statistical differences between groups in the quality-of-life surveys (both mental and physical) as measured by the Short Form-12 health survey and the EuroQol five-dimension questionnaire. There was an improvement in both mental and physical quality-of-life in all patients that began at 6 months after the index ablation and was maintained throughout the 30 months of follow-up. Conclusion Patients treated with cryoballoon as opposed to RFC ablation had significantly fewer repeat ablations, direct-current cardioversions, all-cause rehospitalizations, and cardiovascular rehospitalizations during follow-up. Both patient groups improved in quality-of-life scores after AF ablation. Clinical trial registration ClinicalTrials.gov identifier: NCT01490814

  2. Adenosine-induced atrioventricular block: a rapid and reliable method to assess surgical and radiofrequency catheter ablation of accessory atrioventricular pathways.

    PubMed

    Keim, S; Curtis, A B; Belardinelli, L; Epstein, M L; Staples, E D; Lerman, B B

    1992-04-01

    Adenosine has been shown to inhibit anterograde and retrograde conduction through the atrioventricular (AV) node while having little or no effect on accessory pathway conduction. Its rapid onset of action and short half-life make it particularly suitable for repetitive measurements. In this study, the utility of adenosine was tested in assessing completeness of accessory pathway ablation. Sixteen patients with an accessory pathway were studied (eight surgical ablations, eight catheter ablations with radiofrequency energy). Before ablation, no accessory pathway was sensitive to adenosine. Twelve patients with pre-excitation showed high grade AV node block with maximal pre-excitation on the administration of adenosine during atrial pacing. Four patients with a concealed accessory pathway demonstrated high grade AV block without evidence of latent anterograde accessory pathway conduction. Preablation ventriculoatrial (VA) block was not observed in any of the 16 patients in response to adenosine during ventricular pacing. Immediately after accessory pathway ablation, all patients developed AV and VA block with the administration of adenosine during atrial and ventricular pacing, respectively. These findings were confirmed during follow-up study 1 week later. Atrioventricular block during atrial and ventricular pacing with adenosine affords a reliable and immediate assessment of successful pathway ablation. PMID:1552087

  3. A survey of radiation dose to patients and operators during radiofrequency ablation using computed tomography

    PubMed Central

    Saidatul, A; Azlan, CA; Megat Amin, MSA; Abdullah, BJJ; Ng, KH

    2010-01-01

    Computed tomography (CT) fluoroscopy is able to give real time images to a physician undertaking minimally invasive procedures such as biopsies, percutaneous drainage, and radio frequency ablation (RFA). Both operators executing the procedure and patients too, are thus at risk of radiation exposure during a CT fluoroscopy. This study focuses on the radiation exposure present during a series of radio frequency ablation (RFA) procedures, and used Gafchromic film (Type XR-QA; International Specialty Products, USA) and thermoluminescent dosimeters (TLD-100H; Bicron, USA) to measure the radiation received by patients undergoing treatment, and also operators subject to scatter radiation. The voltage was held constant at 120 kVp and the current 70mA, with 5mm thickness. The duration of irradiation was between 150-638 seconds. Ultimately, from a sample of 30 liver that have undergone RFA, the study revealed that the operator received the highest dose at the hands, which was followed by the eyes and thyroid, while secondary staff dosage was moderately uniform across all parts of the body that were measured. PMID:21611060

  4. Radiofrequency Ablation of Liver Metastases-Software-Assisted Evaluation of the Ablation Zone in MDCT: Tumor-Free Follow-Up Versus Local Recurrent Disease

    SciTech Connect

    Keil, Sebastian Bruners, Philipp; Schiffl, Katharina; Sedlmair, Martin; Muehlenbruch, Georg; Guenther, Rolf W.; Das, Marco; Mahnken, Andreas H.

    2010-04-15

    The purpose of this study was to investigate differences in change of size and CT value between local recurrences and tumor-free areas after CT-guided radiofrequency ablation (RFA) of hepatic metastases during follow-up by means of dedicated software for automatic evaluation of hepatic lesions. Thirty-two patients with 54 liver metastases from breast or colorectal cancer underwent triphasic contrast-enhanced multidetector-row computed tomography (MDCT) to evaluate hepatic metastatic spread and localization before CT-guided RFA and for follow-up after intervention. Sixteen of these patients (65.1 {+-} 10.3 years) with 30 metastases stayed tumor-free (group 1), while the other group (n = 16 with 24 metastases; 62.0 {+-} 13.8 years) suffered from local recurrent disease (group 2). Applying an automated software tool (SyngoCT Oncology; Siemens Healthcare, Forchheim, Germany), size parameters (volume, RECIST, WHO) and attenuation were measured within the lesions before, 1 day after, and 28 days after RFA treatment. The natural logarithm (ln) of the quotient of the volume 1 day versus 28 days after RFA treament was computed: lnQ1//28/0{sub volume}. Analogously, ln ratios of RECIST, WHO, and attenuation were computed and statistically evaluated by repeated-measures ANOVA. One lesion in group 2 was excluded from further evaluation due to automated missegmentation. Statistically significant differences between the two groups were observed with respect to initial volume, RECIST, and WHO (p < 0.05). Furthermore, ln ratios corresponding to volume, RECIST, and WHO differed significantly between the two groups. Attenuation evaluations showed no significant differences, but there was a trend toward attenuation assessment for the parameter lnQ28/0{sub attenuation} (p = 0.0527), showing higher values for group 1 (-0.4 {+-} 0.3) compared to group 2 (-0.2 {+-} 0.2). In conclusion, hepatic metastases and their zone of coagulation necrosis after RFA differed significantly between tumor

  5. Thermal modeling for pulsed radiofrequency ablation: analytical study based on hyperbolic heat conduction.

    PubMed

    López Molina, Juan A; Rivera, María J; Trujillo, Macarena; Berjano, Enrique J

    2009-04-01

    The objectives of this study were to model the temperature progress of a pulsed radiofrequency (RF) power during RF heating of biological tissue, and to employ the hyperbolic heat transfer equation (HHTE), which takes the thermal wave behavior into account, and compare the results to those obtained using the heat transfer equation based on Fourier theory (FHTE). A theoretical model was built based on an active spherical electrode completely embedded in the biological tissue, after which HHTE and FHTE were analytically solved. We found three typical waveforms for the temperature progress depending on the relations between the dimensionless duration of the RF pulse delta(a) and the expression square root of lambda(rho-1), with lambda as the dimensionless thermal relaxation time of the tissue and rho as the dimensionless position. In the case of a unique RF pulse, the temperature at any location was the result of the overlapping of two different heat sources delayed for a duration delta(a) (each heat source being produced by a RF pulse of limitless duration). The most remarkable feature in the HHTE analytical solution was the presence of temperature peaks traveling through the medium at a finite speed. These peaks not only occurred during the RF power switch-on period but also during switch off. Finally, a physical explanation for these temperature peaks is proposed based on the interaction of forward and reverse thermal waves. All-purpose analytical solutions for FHTE and HHTE were obtained during pulsed RF heating of biological tissues, which could be used for any value of pulsing frequency and duty cycle.

  6. Effect of the thermal wave in radiofrequency ablation modeling: an analytical study.

    PubMed

    Molina, Juan A López; Rivera, Maria J; Trujillo, Macarena; Berjano, Enrique J

    2008-03-01

    To date, all radiofrequency heating (RFH) theoretical models have employed Fourier's heat transfer equation (FHTE), which assumes infinite thermal energy propagation speed. Although this equation is probably suitable for modeling most RFH techniques, it may not be so for surgical procedures in which very short heating times are employed. In such cases, a non-Fourier model should be considered by using the hyperbolic heat transfer equation (HHTE). Our aim was to compare the temperature profiles obtained from the FHTE and HHTE for RFH modeling. We built a one-dimensional theoretical model based on a spherical electrode totally embedded and in close contact with biological tissue of infinite dimensions. We solved the electrical-thermal coupled problem analytically by including the power source in both equations. A comparison of the analytical solutions from the HHTE and FHTE showed that (1) for short times and locations close to the electrode surface, the HHTE produced temperatures higher than the FHTE, however, this trend became negligible for longer times, when both equations produced similar temperature profiles (HHTE always being higher than FHTE); (2) for points distant from the electrode surface and for very short times, the HHTE temperature was lower than the FHTE, however, after a delay time, this tendency inverted and the HHTE temperature increased to the maximum; (3) from a mathematical point of view, the HHTE solution showed cuspidal-type singularities, which were materialized as a temperature peak traveling through the medium at a finite speed. This peak rose at the electrode surface, and clearly reflected the wave nature of the thermal problem; (4) the differences between the FHTE and HHTE temperature profiles were smaller for the lower values of thermal relaxation time and locations further from the electrode surface.

  7. Successful radiofrequency catheter ablation of a right posterolateral bypass tract in a patient with Wolff-Parkinson-White syndrome after a previous failed ablative procedure: taking the high road.

    PubMed

    Cohen, T J

    2000-07-01

    A 16-year-old high school basketball player with symptomatic Wolff-Parkinson-White syndrome underwent an unsuccessful radiofrequency catheter ablative procedure from the femoral venous approach. During this procedure, the patient received 30 applications of radiofrequency energy without injury to the accessory pathway. The patient was treated with flecinide 100 mg orally twice daily and rescheduled for a second ablative procedure via the right internal jugular venous approach. At the second session, prior to any right internal jugular venous applications, 3 additional applications were delivered via the right femoral venous approach using a different catheter, without success. A single radiofrequency energy application from the right internal jugular venous approach eliminated the bypass tract in approximately 2 seconds. The superior approach achieved a more stable catheter position thereby eliminating the bypass tract. In conclusion, an alternative plan of attack should be considered after multiple failures from a given approach. In other words, take the high road if you can't take the low road.

  8. Nanodrug-Enhanced Radiofrequency Tumor Ablation: Effect of Micellar or Liposomal Carrier on Drug Delivery and Treatment Efficacy

    PubMed Central

    Moussa, Marwan; Goldberg, S. Nahum; Kumar, Gaurav; Sawant, Rupa R.; Levchenko, Tatyana; Torchilin, Vladimir P.; Ahmed, Muneeb

    2014-01-01

    Purpose To determine the effect of different drug-loaded nanocarriers (micelles and liposomes) on delivery and treatment efficacy for radiofrequency ablation (RFA) combined with nanodrugs. Materials/Methods Fischer 344 rats were used (n = 196). First, single subcutaneous R3230 tumors or normal liver underwent RFA followed by immediate administration of IV fluorescent beads (20, 100, and 500 nm), with fluorescent intensity measured at 4–24 hr. Next, to study carrier type on drug efficiency, RFA was combined with micellar (20 nm) or liposomal (100 nm) preparations of doxorubicin (Dox; targeting HIF-1α) or quercetin (Qu; targeting HSP70). Animals received RFA alone, RFA with Lipo-Dox or Mic-Dox (1 mg IV, 15 min post-RFA), and RFA with Lipo-Qu or Mic-Qu given 24 hr pre- or 15 min post-RFA (0.3 mg IV). Tumor coagulation and HIF-1α orHSP70 expression were assessed 24 hr post-RFA. Third, the effect of RFA combined with IV Lipo-Dox, Mic-Dox, Lipo-Qu, or Mic-Qu (15 min post-RFA) compared to RFA alone on tumor growth and animal endpoint survival was evaluated. Finally, drug uptake was compared between RFA/Lipo-Dox and RFA/Mic-Dox at 4–72 hr. Results Smaller 20 nm beads had greater deposition and deeper tissue penetration in both tumor (100 nm/500 nm) and liver (100 nm) (p<0.05). Mic-Dox and Mic-Qu suppressed periablational HIF-1α or HSP70 rim thickness more than liposomal preparations (p<0.05). RFA/Mic-Dox had greater early (4 hr) intratumoral doxorubicin, but RFA/Lipo-Dox had progressively higher intratumoral doxorubicin at 24–72 hr post-RFA (p<0.04). No difference in tumor growth and survival was seen between RFA/Lipo-Qu and RFA/Mic-Qu. Yet, RFA/Lipo-Dox led to greater animal endpoint survival compared to RFA/Mic-Dox (p<0.03). Conclusion With RF ablation, smaller particle micelles have superior penetration and more effective local molecular modulation. However, larger long-circulating liposomal carriers can result in greater intratumoral drug accumulation over

  9. Radiofrequency ablation with a vibrating catheter: A new method for electrode cooling.

    PubMed

    Yu, Kaihong; Yamashita, Tetsui; Shingyochi, Shigeaki; Matsumoto, Kazuo; Ohta, Makoto

    2016-05-01

    A new electrode cooling system using a vibrating catheter is described for conditions of low blood flow when saline irrigation cannot be used. Vibrations of the catheter are hypothesized to disturb blood flow around the electrode, leading to increased convective cooling of the electrode. The aim of this study is to confirm the cooling effect of vibration and investigate the associated mechanisms. As methods, an in vitro system with polyvinyl alcohol-hydrogel (PVA-H) as ablated tissue and saline flow in an open channel was used to measure changes in electrode and tissue temperatures under vibration of 0-63 Hz and flow velocity of 0-0.1 m/s. Flow around the catheter was observed using particle image velocimetry (PIV). Results show that under conditions of no flow, electrode temperatures decreased with increasing vibration frequency, and in the absence of vibrations, electrode temperatures decreased with increasing flow velocity. In the presence of vibrations, electrode temperatures decreased under conditions of low flow velocity, but not under those of high flow velocity. PIV analyses showed disturbed flow around the vibrating catheter, and flow velocity around the catheter increased with higher-frequency vibrations. In conclusion, catheter vibration facilitated electrode cooling by increasing flow around the catheter, and cooling was proportional to vibration frequency.

  10. Thermal compression and molding of atherosclerotic vascular tissue with use of radiofrequency energy: implications for radiofrequency balloon angioplasty.

    PubMed

    Lee, B I; Becker, G J; Waller, B F; Barry, K J; Connolly, R J; Kaplan, J; Shapiro, A R; Nardella, P C

    1989-04-01

    The combined delivery of pressure and thermal energy may effectively remodel intraluminal atherosclerotic plaque and fuse intimal tears. To test these hypotheses with use of a non-laser thermal energy source, radiofrequency energy was delivered to postmortem human atherosclerotic vessels from a metal "hot-tip" catheter, block-mounted bipolar electrodes and from a prototype radiofrequency balloon catheter. Sixty-two radiofrequency doses delivered from a metal electrode tip produced dose-dependent ablation of atherosclerotic plaque, ranging from clean and shallow craters with histologic evidence of thermal compression at doses less than 40 J to tissue charring and vaporization at higher (greater than 80 J) doses. Lesion dimensions ranged between 3.14 and 3.79 mm in diameter and 0.20 and 0.47 mm in depth. Tissue perforation was not observed. To test the potential for radiofrequency fusion of intimal tears, 5 atm of pressure and 200 J radiofrequency energy were delivered from block-mounted bipolar electrodes to 48 segments of human atherosclerotic aorta, which had been manually separated into intima-media and media-adventitial layers. Significantly stronger tissue fusion resulted (28.5 +/- 3.3 g) with radiofrequency compared with that with pressure alone (4.8 +/- 0.26 g; p less than 0.0001). A prototype radiofrequency balloon catheter was used to deliver 3 atm of balloon pressure with or without 200 J radiofrequency energy to 20 postmortem human atherosclerotic arterial segments. In 10 of 10 radiofrequency-treated vessels, thermal "molding" of both normal and atherosclerotic vessel wall segments resulted with increased luminal diameter and histologic evidence of medial myocyte damage.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Thermal compression and molding of atherosclerotic vascular tissue with use of radiofrequency energy: implications for radiofrequency balloon angioplasty

    SciTech Connect

    Lee, B.I.; Becker, G.J.; Waller, B.F.; Barry, K.J.; Connolly, R.J.; Kaplan, J.; Shapiro, A.R.; Nardella, P.C.

    1989-04-01

    The combined delivery of pressure and thermal energy may effectively remodel intraluminal atherosclerotic plaque and fuse intimal tears. To test these hypotheses with use of a non-laser thermal energy source, radiofrequency energy was delivered to postmortem human atherosclerotic vessels from a metal hot-tip catheter, block-mounted bipolar electrodes and from a prototype radiofrequency balloon catheter. Sixty-two radiofrequency doses delivered from a metal electrode tip produced dose-dependent ablation of atherosclerotic plaque, ranging from clean and shallow craters with histologic evidence of thermal compression at doses less than 40 J to tissue charring and vaporization at higher (greater than 80 J) doses. Lesion dimensions ranged between 3.14 and 3.79 mm in diameter and 0.20 and 0.47 mm in depth. Tissue perforation was not observed. To test the potential for radiofrequency fusion of intimal tears, 5 atm of pressure and 200 J radiofrequency energy were delivered from block-mounted bipolar electrodes to 48 segments of human atherosclerotic aorta, which had been manually separated into intima-media and media-adventitial layers. Significantly stronger tissue fusion resulted (28.5 +/- 3.3 g) with radiofrequency compared with that with pressure alone (4.8 +/- 0.26 g; p less than 0.0001). A prototype radiofrequency balloon catheter was used to deliver 3 atm of balloon pressure with or without 200 J radiofrequency energy to 20 postmortem human atherosclerotic arterial segments. In 10 of 10 radiofrequency-treated vessels, thermal molding of both normal and atherosclerotic vessel wall segments resulted with increased luminal diameter and histologic evidence of medial myocyte damage.

  12. Modified technique for determining therapeutic response to radiofrequency ablation therapy for hepatocellular carcinoma using US-volume system.

    PubMed

    Hiraoka, Atsushi; Hirooka, Masashi; Koizumi, Yohei; Hidaka, Satoshi; Uehara, Takahide; Ichikawa, Soichi; Hasebe, Aki; Miyamoto, Yasunao; Ninomiya, Tomoyuki; Michitaka, Kojiro; Horiike, Norio; Yamashita, Yoshimasa; Hiasa, Yoichi; Matsuura, Bunzo; Onji, Morikazu

    2010-02-01

    In radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), microbubbles appearing during the procedure make it difficult to determine effectiveness with ultrasonography (US) imaging. We developed a modified US-volume system and evaluated its efficacy for demonstrating response to therapeutic RFA. Our US-volume system displays multiplanar reconstruction (MPR) images providing a synchronized view with a US image along with past US-volume data in real-time side-by-side on a personal computer. Seventy-eight patients (94 nodules) were enrolled, of whom 35 (47 nodules) were evaluated using this system (US-volume group) and compared to the other 43 (47 nodules) examined before development of our system (control group). All nodules were clearly depicted by US. If the shortage of margin was predicted with US-volume system, we performed additional needle insertion. Tumor necrosis following RFA was graded by dynamic computed tomography as follows: Grade A, necrotic area surrounded in all directions with an adequate margin (>or=5 mm); Grade B, necrotic area surrounded in all directions, though some margin areas <5 mm; and Grade C, residual tumor or necrotic area smaller than the target tumor. In the US-volume group, the average tumor size was not smaller than that in the control (15.9+/-4.9 vs. 16.0+/-4.3 mm) and adequate margins were obtained (Grade A, B, C, 45/1/1 vs. 35/8/4; P<0.01). Further, there was a significant reduction in numbers of RFA sessions as compared to the control (1.03+/-0.17 vs. 1.12+/-0.32; P<0.01). In HCC patients undergoing RFA, our modified US-volume system accurately demonstrated therapeutic response, which led to a reduced number of RFA sessions.

  13. Percutaneous Radiofrequency Ablation and Transcatheter Arterial Chemoembolization for Hypervascular Hepatocellular Carcinoma: Rate and Risk Factors for Local Recurrence

    SciTech Connect

    Murakami, Tomonori Ishimaru, Hideki; Sakamoto, Ichiro; Uetani, Masataka; Matsuoka, Yohjiro; Daikoku, Manabu; Honda, Sumihisa; Koshiishi, Takeshi; Fujimoto, Toshifumi

    2007-07-15

    Purpose. To analyze local recurrence-free rates and risk factors for recurrence following percutaneous radiofrequency ablation (RFA) or transcatheter arterial chemoembolization (TACE) for hypervascular hepatocellular carcinoma (HCC). Methods. One hundred and nine nodules treated by RFA and 173 nodules treated by TACE were included. Hypovascular nodules were excluded from this study. Overall local recurrence-free rates of each treatment group were calculated using the Kaplan-Meier method. The independent risk factors of local recurrence and the hazard ratios were analyzed using Cox's proportional-hazards regression model. Based on the results of multivariate analyses, we classified HCC nodules into four subgroups: central nodules {<=}2 cm or >2 cm and peripheral nodules {<=}2 cm or >2 cm. The local recurrence-free rates of these subgroups for each treatment were also calculated. Results. The overall local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p = 0.013). The 24-month local recurrence-free rates in the RFA and TACE groups were 60.0% and 48.9%, respectively. In the RFA group, the only significant risk factor for recurrence was tumor size >2 cm in greatest dimension. In the TACE group, a central location was the only significant risk factor for recurrence. In central nodules that were {<=}2 cm, the local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p < 0.001). In the remaining three groups, there was no significant difference in local recurrence-free rate between the two treatment methods. Conclusion. A tumor diameter of >2 cm was the only independent risk factor for local recurrence in RFA treatment, and a central location was the only independent risk factor in TACE treatment. Central lesions measuring {<=}2 cm should be treated by RFA.

  14. Subjective and objective parameters in the evaluation of radiofrequency ablation of the inferior turbinate do not correlate: A pilot study.

    PubMed

    Tomazic, Peter Valentin; Gerstenberger, Claus; Rant, Bettina; Nemetz, Ulrike; Brezjak-Kahlert, Christiana; Wolf, Axel; Freudenschuss, Kurt; Wolf, Gerald

    2016-08-01

    Inferior turbinate hypertrophy is a common cause of nasal obstruction. We conducted a prospective study to correlate subjective and objective parameters in assessing the effectiveness of radiofrequency ablation (RFA). Our initial study population was made up of 10 patients who presented with nasal obstruction; 1 patient was lost to follow-up, leaving us with 7 women and 2 men, aged 26 to 65 years (mean: 37.9 ± 12.8), and 16 turbinates (7 bilateral, 1 right, and 1 left). Visual analogue scale (VAS) scores, Nasal Obstruction and Symptom Evaluation (NOSE) questionnaire scores, rhinomanometry results, and CT- and MRI-based volumetry were obtained before RFA and 6 months afterward. For the subjective parameters, the mean pre- and postoperative VAS scores for the 16 turbinates were 6.6 ± 1.6 and 2.8 ± 2.0 (p < 0.001), respectively, and the mean pre- and postoperative NOSE scores in the 9 patients were 15.3 ± 3.1 and 5.8 ± 5.4 (p = 0.003). For the objective parameters, the mean pre- and postoperative rhinomanometry values at 150 Pa were 241.0 ± 141.3 and 265.4 ± 157.3 ml/sec (p = 0.403), and the mean pre- and postoperative volumetry values were 5.3 ± 2.5 and 5.0 ± 2.1 cm(3) (p = 0.551). Note that only the differences in the subjective parameters reached statistical significance. RFA of the inferior turbinates as a treatment for nasal obstruction is safe and easy. However, our study found a discrepancy between the subjective and objective outcomes parameters, as the former showed highly significant improvement and the latter showed only a slight improvement that did not reach statistical significance. PMID:27551845

  15. Percutaneous ethanol injection therapy is comparable to radiofrequency ablation in hepatocellular carcinoma smaller than 1.5 cm

    PubMed Central

    Yu, Su Jong; Yoon, Jung-Hwan; Lee, Jeong Min; Lee, Jae Young; Kim, Se Hyung; Cho, Young Youn; Yoo, Jeong-Ju; Lee, Minjong; Lee, Dong Hyeon; Cho, Yuri; Cho, Eun Ju; Lee, Jeong-Hoon; Kim, Yoon Jun; Kim, Chung Yong

    2016-01-01

    Abstract Although percutaneous ethanol injection therapy (PEIT) is best indicated for patients with small hepatocellular carcinoma (HCC), the survival advantage of PEIT needs confirmation in real-world practice. This study was approved by the institutional review board, and the informed consent was waived. The study included 535 consecutive patients with newly diagnosed early stage (Barcelona Clinic Liver Cancer [BCLC] 0 or A) HCC who underwent initially radiofrequency ablation (RFA) (n = 288) or PEIT (n = 247) from January 2005 to December 2010. The primary outcome was overall survival (OS) and the secondary outcome was time to progression (TTP). The longest diameters of tumors of the groups differed significantly and larger for RFA group than PEIT group (P < 0.001; 1.94 ± 0.65 cm vs 1.60 ± 0.50 cm, respectively). The 5-year OS rates were 72.2% in the RFA group and 67.4% in the PEIT group (P = 0.608). Even after propensity score matching, OS rates between the 2 groups were similar (5-year OS: 72.8% with RFA [n = 175] and 68.0% with PEIT [n = 175]) (P = 0.709). Moreover, in patients with the longest diameter of tumors (≤1.5 cm), multivariate Cox regression analysis showed that the treatment modality was not a significant prognosticator for OS (hazard ratio [HR], 1.690; 95% confidence interval [CI], 0.828–3.449; P = 0.149) and time to progression (HR, 1.160; 95% CI, 0.773–1.740; P = 0.474). PEIT and RFA show equal effectiveness in treating HCCs <1.5 cm in terms of OS and time to progression. PMID:27583865

  16. The procedure outcome of laparoscopic resection for ‘small’ hepatocellular carcinoma is comparable to vlaparoscopic radiofrequency ablation

    PubMed Central

    Casaccia, Marco; Santori, Gregorio; Bottino, Giuliano; Diviacco, Pietro; Negri, Antonella De; Moraglia, Eva; Adorno, Enzo

    2015-01-01

    BACKGROUND: The aim of this study was to compare the effectiveness of laparoscopic liver resection (LLR) and laparoscopic radiofrequency ablation (LRFA) in the treatment of small nodular hepatocellular carcinoma (HCC). PATIENTS AND METHODS: We enrolled 50 cirrhotic patients with similar baseline characteristics that underwent LLR (n = 26) or LRFA (n = 24), in both cases with intraoperative ultrasonography. Operative and peri-operative data were retrospectively evaluated. RESULTS: LLR included anatomic resection in eight cases and non-anatomic resection in 18. In LRFA patients, a thermoablation of 62 nodules was achieved. Between LLR and LRFA groups, a significant difference was found both for median diameters of treated HCC nodules (30 vs. 17.1 mm; P < 0.001) and the number of treated nodules/patient (1.29 ± 0.62 vs. 2.65 ± 1.55; P < 0.001). A conversion to laparotomy occurred in two LLR patient (7.7%) for bleeding. No deaths occurred in both groups. Morbidity rates were 26.9% in the LLR group versus 16.6% in the LRFA group (P = 0.501). Hospital stay in the LLR and LRFA group was 8.30 ± 6.52 and 6.52 ± 2.69 days, respectively (P = 0.022). The surgical margin was free of tumour cells in all LLR patients, with a margin <5 mm in only one case. In the LRFA group, a complete response was achieved in 90.3% of thermoablated HCC nodules at the 1-month post-treatment computed tomography evaluation. CONCLUSIONS: LLR for small peripheral HCC in patients with chronic liver disease represents a valid alternative to LRFA in terms of patient toleration, surgical outcome of the procedure, and short-term morbidity. PMID:26622111

  17. Preparation of liposomal amiodarone and investigation of its cardiomyocyte-targeting ability in cardiac radiofrequency ablation rat model.

    PubMed

    Zhuge, Ying; Zheng, Zhi-Feng; Xie, Mu-Qing; Li, Lin; Wang, Fang; Gao, Feng

    2016-01-01

    The objective of this study was to develop an amiodarone hydrochloride (ADHC)-loaded liposome (ADHC-L) formulation and investigate its potential for cardiomyocyte targeting after cardiac radiofrequency ablation (CA) in vivo. The ADHC-L was prepared by thin-film method combined with ultrasonication and extrusion. The preparation process was optimized by Box-Behnken design with encapsulation efficiency as the main evaluation index. The optimum formulation was quantitatively obtained with a diameter of 99.9±0.4 nm, a zeta potential of 35.1±10.9 mV, and an encapsulation efficiency of 99.5%±13.3%. Transmission electron microscopy showed that the liposomes were spherical particles with integrated bilayers and well dispersed with high colloidal stability. Pharmacokinetic studies were investigated in rats after intravenous administration, which revealed that compared with free ADHC treatment, ADHC-L treatment showed a 5.1-fold increase in the area under the plasma drug concentration-time curve over a period of 24 hours (AUC0-24 h) and an 8.5-fold increase in mean residence time, suggesting that ADHC-L could facilitate drug release in a more stable and sustained manner while increasing the circulation time of ADHC, especially in the blood. Biodistribution studies of ADHC-L demonstrated that ADHC concentration in the heart was 4.1 times higher after ADHC-L treatment in CA rat model compared with ADHC-L sham-operated treatment at 20 minutes postinjection. Fluorescence imaging studies further proved that the heart-targeting ability of ADHC-L was mainly due to the CA in rats. These results strongly support that ADHC-L could be exploited as a potential heart-targeting drug delivery system with enhanced bioavailability and reduced side effects for arrhythmia treatment after CA. PMID:27313453

  18. Predictors Of Treatment Failure After Radiofrequency Ablation For Intramucosal Adenocarcinoma in Barrett Esophagus: A Multi-institutional Retrospective Cohort Study.

    PubMed

    Agoston, Agoston T; Strauss, Adam C; Dulai, Parambir S; Hagen, Catherine E; Muzikansky, Alona; Fudman, David I; Abrams, Julian A; Forcione, David G; Jajoo, Kunal; Saltzman, John R; Odze, Robert D; Lauwers, Gregory Y; Gordon, Stuart R; Lightdale, Charles J; Rothstein, Richard I; Srivastava, Amitabh

    2016-04-01

    Radiofrequency ablation (RFA), with or without endoscopic mucosal resection (EMR), is a safe, effective, and durable treatment option for Barrett esophagus (BE)-associated dysplasia (DYS), but few studies have identified predictors of treatment failure in BE-associated intramucosal adenocarcinoma (IMC). The aim of this study was to determine the rate of IMC eradication when using RFA±EMR and to identify clinical and pathologic predictors of treatment failure. A retrospective review of medical records and a central review of index histologic parameters were performed for 78 patients who underwent RFA±EMR as the primary treatment for biopsy-proven IMC at 4 academic tertiary medical centers. Complete eradication (CE) (absence of IMC/DYS on first follow-up endoscopy) was achieved in 86% of patients, and durable eradication (DE) (CE with no recurrence of IMC/DYS until last follow-up) was achieved in 78% of patients, with significant variation between the 4 study sites (P=0.03 and 0.09 by analysis of variance for DE and CE, respectively). Use of EMR before RFA significantly reduced the risk for treatment failure for IMC/DYS (hazard ratio, 0.15; 95% confidence interval, 0.05-0.48; P=0.001), whereas IMC involving ≥50% of the columnar metaplastic area on index examination significantly increased the risk for treatment failure (hazard ratio, 4.24; 95% confidence interval, 1.53-11.7; P=0.005). Endoscopic and pathologic factors associated with treatment failure in BE-associated IMC treated with RFA±EMR may help identify the subset of IMC patients for whom a more aggressive initial approach may be justified.

  19. Comparative Effects of Dexmedetomidine and Propofol on US-Guided Radiofrequency Ablation of Hepatic Neoplasm Under Monitored Anesthesia Care

    PubMed Central

    Joung, Kyoung-Woon; Choi, Seong-Soo; Jang, Dong-Min; Kong, Yu-Gyeong; Lee, Hwa-Mi; Shim, Ji-Hoon; Won, Hyung-Jin; Shin, Yong-Moon; Kim, Pyo-Nyun; Song, Myung-Hee

    2015-01-01

    Abstract Percutaneous radiofrequency ablation (RFA) is a useful and safe procedure for treating hepatic neoplasm. However, liver RFA causes severe pain, which thereby increases the demand for monitored anesthesia care (MAC). Here, we compared the efficacy and safety of propofol and dexmedetomidine, which are commonly administered during MAC when performing RFA to assess hepatic neoplasm. In this randomized controlled trial, 40 patients were randomly allocated to 2 groups for elective RFA. Patients received either dexmedetomidine (group D) or propofol (group P). Both groups received the continuous infusion of remifentanil for pain control. The primary outcomes were opioid consumption and differences in partial pressure of arterial carbon dioxide (PaCO2) between pre- and postprocedure RFA. In addition, hemodynamic parameters, patient satisfaction, and interventional radiologist satisfaction were determined. There were significant differences in opioid consumption (50.1 ± 16.8 ng/kg/min [group D] vs 71.2 ± 18.7 ng/kg/min [group P]; P = 0.001) and delta PaCO2 (10.4 ± 6.4 mm Hg vs 17.2 ± 9.2 mm Hg, respectively; P = 0.016). Moreover, respiratory rates were significantly different between groups during RFA (P < 0.001). However, blood pressure and heart rate did not significantly change during RFA. Neither patient nor interventional radiologist satisfaction was significantly different between groups. Dexmedetomidine provides better respiratory stability and reduces opioid consumption in comparison with propofol when administered under MAC when performing RFA for hepatic neoplasm. PMID:26266387

  20. Radiofrequency ablation-increased CXCL10 is associated with earlier recurrence of hepatocellular carcinoma by promoting stemness.

    PubMed

    Ouyang, Yabo; Liu, Kai; Hao, Meijun; Zheng, Rongling; Zhang, Chunmiao; Wu, Yanning; Zhang, Xiaofeng; Li, Ning; Zheng, Jiasheng; Chen, Dexi

    2016-03-01

    Radiofrequency ablation (RFA) represents a valuable choice in hepatocellular carcinoma (HCC); however, local recurrence of HCC is common after RFA. Here, 20 primary HCC patients treated by RFA were enrolled. Before (termed 0d) and after RFA treatment for 1 and 7 days (termed 1d and 7d, respectively), plasma and noncancerous tissue were collected. ELISA assay showed that plasma C-X-C motif chemokine 10 (CXCL10) was increased in ten patients (type I patients) but decreased in the other 10 patients (type II patients). The mean interval for HCC recurrence in type I patients was less than the mean interval in type II patients. Interestingly, a significant negative correlation between interval for HCC recurrence and fold change of plasma CXCL10 (1d/0d or 7d/0d) was identified, suggesting that RFA-induced CXCL10 is associated with earlier HCC recurrence. Immunofluorescence assay showed that the receptor of CXCL10, chemokine (C-X-C motif) receptor 3 (CXCR3), was significantly increased in type I, but not type II, patients after RFA. In vitro assay demonstrated that CXCL10 stimulus increased the rate of CD133(+) cancer stem cells (CSCs) in HepG2 cells by binding to CXCR3 and then inducing c-Myc expression. Many studies have reported that induction of CD133(+) CSCs contributes to HCC recurrence. Thus, CXCL10-increased CD133(+) CSCs by activating CXCR3/c-Myc pathway might accelerate HCC recurrence after RFA. These data might have potential implications for HCC therapy.

  1. Comparison of laparoscopic hepatectomy, percutaneous radiofrequency ablation and open hepatectomy in the treatment of small hepatocellular carcinoma

    PubMed Central

    Lai, Chong; Jin, Ren-an; Liang, Xiao; Cai, Xiu-jun

    2016-01-01

    Objective: Three mainstream techniques—laparoscopic hepatectomy (LH), percutaneous radiofrequency ablation (pRFA), and open hepatectomy (OH)—were compared in this study, in terms of their efficacies in the treatment of small hepatocellular carcinoma (HCC). Methods: A comparative study was performed within a total of 94 patients diagnosed with small HCC in our hospital from 2005 to 2010, who underwent LH (28), RFA (33), or OH (33). They had either a single tumor lesion of less than 5 cm or up to three nodules with diameters of less than 3 cm each. Outcomes were carefully evaluated throughout a 3-year follow-up interval and statistically interpreted. Results: The pRFA group had a significantly lower disease-free survival rate compared with the two surgical groups (P=0.001) and significantly shorter overall survival (P=0.005), while the LH group and the OH group had no difference in survival results. For patients younger than 60 years old, surgical approaches offered a better long-term overall survival prognosis (P=0.008). There were no statistically significant differences among the three groups in overall survival for elderly patients (P=0.104). Conclusions: Among patients with small HCC, LH may provide better curative effects than pRFA without increasing complication rates. pRFA leads to faster recurrence than surgical resections. LH has similar therapeutic effects to OH and causes less trauma. For patients younger than 60 years old, LH may be the best curative treatment. Elderly patients may choose either surgery or pRFA. PMID:26984844

  2. Preparation of liposomal amiodarone and investigation of its cardiomyocyte-targeting ability in cardiac radiofrequency ablation rat model

    PubMed Central

    Zhuge, Ying; Zheng, Zhi-Feng; Xie, Mu-Qing; Li, Lin; Wang, Fang; Gao, Feng

    2016-01-01

    The objective of this study was to develop an amiodarone hydrochloride (ADHC)-loaded liposome (ADHC-L) formulation and investigate its potential for cardiomyocyte targeting after cardiac radiofrequency ablation (CA) in vivo. The ADHC-L was prepared by thin-film method combined with ultrasonication and extrusion. The preparation process was optimized by Box–Behnken design with encapsulation efficiency as the main evaluation index. The optimum formulation was quantitatively obtained with a diameter of 99.9±0.4 nm, a zeta potential of 35.1±10.9 mV, and an encapsulation efficiency of 99.5%±13.3%. Transmission electron microscopy showed that the liposomes were spherical particles with integrated bilayers and well dispersed with high colloidal stability. Pharmacokinetic studies were investigated in rats after intravenous administration, which revealed that compared with free ADHC treatment, ADHC-L treatment showed a 5.1-fold increase in the area under the plasma drug concentration–time curve over a period of 24 hours (AUC0–24 h) and an 8.5-fold increase in mean residence time, suggesting that ADHC-L could facilitate drug release in a more stable and sustained manner while increasing the circulation time of ADHC, especially in the blood. Biodistribution studies of ADHC-L demonstrated that ADHC concentration in the heart was 4.1 times higher after ADHC-L treatment in CA rat model compared with ADHC-L sham-operated treatment at 20 minutes postinjection. Fluorescence imaging studies further proved that the heart-targeting ability of ADHC-L was mainly due to the CA in rats. These results strongly support that ADHC-L could be exploited as a potential heart-targeting drug delivery system with enhanced bioavailability and reduced side effects for arrhythmia treatment after CA. PMID:27313453

  3. N-butyl cyanoacrylate embolization with blood flow control of an arterioportal shunt that developed after radiofrequency ablation of hepatocellular carcinoma.

    PubMed

    Sonomura, Tetsuo; Kawai, Nobuyuki; Kishi, Kazushi; Ikoma, Akira; Sanda, Hiroki; Nakata, Kouhei; Minamiguchi, Hiroki; Nakai, Motoki; Hosokawa, Seiki; Tamai, Hideyuki; Sato, Morio

    2014-01-01

    We present a case of a patient with rapid deterioration of esophageal varices caused by portal hypertension accompanied by a large arterioportal shunt that developed after radiofrequency ablation of hepatocellular carcinoma. We used n-butyl cyanoacrylate (NBCA) as an embolic material to achieve pinpoint embolization of the shunt, because the microcatheter tip was 2 cm away from the shunt site. Under hepatic arterial flow control using a balloon catheter, the arterioportal shunt was successfully embolized with NBCA, which caused an improvement in the esophageal varices.

  4. Radiofrequency ablation of renal tumors with an expandable multitined electrode: results, complications, and pilot evaluation of cooled pyeloperfusion for collecting system protection.

    PubMed

    Rouvière, Olivier; Badet, Lionel; Murat, François Joseph; Maréchal, Jean Marie; Colombel, Marc; Martin, Xavier; Lyonnet, Denis; Gelet, Albert

    2008-01-01

    The objective of this study was to retrospectively evaluate the results of radiofrequency ablation (RFA) of renal tumors with an impedance-based system using an expandable multitined electrode. Twenty-two patients (30 tumors) were treated with RFA over a 7-year period, percutaneously (16 tumors) or intraoperatively (14 tumors). Follow-up imaging was performed at 1-3, 6, and 12 months and yearly thereafter. Twenty-seven of 30 tumors (19/22 patients) showed no residual tumor on the first imaging control. Two residual tumors were successfully ablated by a second RFA procedure. Our mean follow-up period was 35 months (range, 3-84 months). Two tumors that had been completely ablated based on imaging criteria recurred 11 and 48 months after RFA. One was treated by partial nephrectomy. The other one was not treated because the patient developed bone metastases. One patient had nephrectomy because of an RFA-induced ureteropelvic junction stricture. Nine patients (11 sessions) had a pyeloperfusion of cooled saline during RFA. None developed symptomatic complications, even though in three patients the ablation zone extended to the closest calyx (3-5 mm from the tumor). We conclude that RFA of renal tumors is promising, but serious complications to the collecting system must be taken into consideration. Prophylactic per-procedural cooling of the collecting system is feasible but needs further assessment.

  5. FDG-MicroPET and Diffusion-Weighted MR Image Evaluation of Early Changes After Radiofrequency Ablation in Implanted VX2 Tumors in Rabbits

    SciTech Connect

    Ohira, Tomohiro Okuma, Tomohisa; Matsuoka, Toshiyuki; Wada, Yasuhiro; Nakamura, Kenji; Watanabe, Yasuyoshi; Inoue, Yuichi

    2009-01-15

    The objective of this study was to evaluate the early changes after radiofrequency ablation (RFA) in VX2 rabbit tumors implanted into the back muscles by diffusion-weighted magnetic resonance (MR) imaging and {sup 18}F-2-fluoro-2-deoxy-D-glucose positron emission tomography ({sup 18}F-FDG PET). Percutaneous CT-guided RFA was conducted in seven rabbits with implanted VX2 tumors. VX2 tumors on the other side were untreated and served as the control. MR imaging was performed with a clinical 1.5-T instrument 2 days after RFA, and FDG-PET, using a high-resolution PET scanner for small animals, was obtained 3 days after the procedure. The mean apparent diffusion coefficient (ADC) values and radioactivity count of untreated and ablated tumors were calculated. Untreated VX2 tumors showed hyperintensity on T1-, T2-, and diffusion-weighted MR images, ring-enhanced on contrast-enhanced T1-weighted imaging, and ring-shaped FDG accumulation on FDG-PET. Ablated VX2 tumors showed slight hyperintensity on T1-, T2-, and diffusion-weighed images, slight enhancement on contrast-enhanced T1-weighted images, and low accumulation on FDG-PET. The ADC value of ablated VX2 tumors (1.52 {+-} 0.24 x 10{sup -3} mm{sup 2}/s) was significantly higher than that of untreated tumors (1.09 {+-} 0.12 x 10{sup -3}; p < 0.05). The tumor/muscle ratio of ablated tumors (0.5 {+-} 0.3) was significantly lower than that of untreated tumors (11.6 {+-} 3.2; p < 0.05). Histopathological examination confirmed the lack of viable tumor cells in the ablated lesions. The results indicate that both ADC value and FDG-PET are potentially useful markers for monitoring the early effects of RFA.

  6. The clinical effect and relevant mechanism of combined sorafenib and radiofrequency ablation in the treatment of early small hepatocellular carcinoma

    PubMed Central

    Yan, Shi-Yan; Zhang, Yi; Sun, Chao; Cao, Hai-Xia; Li, Guang-Ming; Wang, Yu-Qin; Fan, Jian-Gao

    2016-01-01

    The number of cases with hepatocellular carcinoma (HCC) are on the increase. The aim of the present study was to investigate the clinical effect and relevant mechanism of combined sorafenib and radiofrequency ablation (RFA) in the treatment of the early small HCC. A total of 120 cases of patients with small HCC that presented during the period of May 2007 to June 2010 were selected and divided into the surgery (n=60) and RF (n=60) groups according to the treatment method employed. The surgery group was treated with a laparotomy resection and the RF group was treated with combined sorafenib and RFA, and a comparative analysis was made between the two groups with regard to recurrence rates, adverse reactions, and survival rates. After treatment of 1 month, the radical effective rate of the surgery and RF groups was 100%. Contrast-enhanced ultrasound images of the patients in the RF group were taken. During the 5-year follow-up, the tumor recurrence rate in the surgery group was 18.3%, significantly lower than that in the RF group where the tumor recurrence rate was 38.3% (P<0.05). The occurrence rate of postoperative pain, fever, abdominal bleeding, infection, and other complications of patients in the surgery group was significantly higher than the complication occurrence rate (P<0.05) of the patients in the RF group. The average survival time of the patients in the surgery group was 51.2±1.5 months and the survival rates during the first, third and fifth year were 90.7, 71.5 and 56.7%, respectively. Additionally, the average survival time of the patients in the RF group was 64.6±2.4 months and the survival rates during the first, third and fifth year were 91.1, 72.8 and 57.5%, respectively. The difference between the two groups was not statistically significant. The tumor-free survival rates in the surgery group during the first, third and fifth year were 87.8, 44.3 and 33.2%, respectively, while the tumor-free survival rates in the RF group during the first

  7. Radiofrequency Ablation Versus Partial Nephrectomy in Treating Small Renal Tumors: A Systematic Review and Meta-Analysis.

    PubMed

    Yin, Xiaotao; Cui, Liang; Li, Fanglong; Qi, Siyong; Yin, Zhaoyang; Gao, Jiangping

    2015-12-01

    Radiofrequency ablation (RFA) has emerged as an alternative treatment to surgical partial nephrectomy (PN) in the treatment of small renal tumors (SRTs). But its safety and oncological efficacy are still controversial. We conducted this systematic review and meta-analysis to compare the peritoperative and oncological outcomes of RFA and PN in the treatment of SRTs. Pubmed, EMBASE, Cochrane CENTRAL, and Web of Science were searched to identify eligible studies that compared the RFA and PN in the treatment of SRTs. Twelve retrospective studies that compared RFA with PN in the treatment of SRTs met our selection criterion and were included in this meta-analysis. The pooled results indicated that the local recurrence rate (4.14% vs 4.10%, RR: 1.18, 95% CI: 0.68, 2.07, P = 0.550) and distant metastases rate (2.76% vs 1.89%, RR: 1.31, 95% CI: 0.70, 2.46, P = 0.686) were not significantly different between the RFA group and the PN group. In terms of perioperative outcomes, RFA was associated with shorter length of stay (LOS) (WMD: -2.02 days, 95% CI: -2.77, -1.27, P < 0.001), lower eGFR decline after treatment (WMD: -3.90, 95% CI: -6.660, -1.140, P = 0.006). However, the overall perioperative complication rate (7.5% vs 6.2%, RR:1.10, 95% CI: 0.64, 1.87, P = 0.740) and the major complication rate (3.7% vs 4.4%, RR: 0.83, 95% CI: 0.43, 1.60, P = 0.579) were both similar between RFA and PN groups. Compared with PN, RFA achieves an equal oncological outcome for SRTs with similar local recurrence rate and distant metastases rate. Additionally, RFA is associated with a similar perioperative complication rate, lower decline of eGFR, and shorter LOS. Therefore, RFA is an effective option in the treatment of SRTs for selected patients. PMID:26683944

  8. Percutaneous Radiofrequency Ablation of Painful Osseous Metastases: A Multi-center American College of Radiology Imaging Network Trial

    PubMed Central

    Dupuy, Damian E.; Liu, Dawei; Hartfeil, Donna; Hanna, Lucy; Blume, Jeffrey D.; Ahrar, Kamran; Lopez, Robert; Safran, Howard; DiPetrillo, Thomas

    2009-01-01

    Background To determine if radiofrequency ablation (RFA) can safely reduce pain from osseous metastatic disease. Methods A single arm prospective trial in patients with a single painful bone metastasis with unremitting pain of at least a score above 50 on a pain scale of 0–100. Percutaneous CT guided RFA of the bone metastasis to temperatures above 60 degrees Celsius was performed. Endpoints were the toxicity and pain effects of RFA before and at 2 weeks, one and three months after RFA. Results 55 patients completed RFA. Grade 3 toxicities occurred in 3 of 55 patients (5%). RFA reduced pain at 1- and 3-month for all pain assessment measures. The average increase in pain relief from pre-RFA to 1-month follow-up is 26.27 (95% CI, 17.65 to 34.89, P<0.0001) and the increase from pre-RFA to 3-month follow-up is 16.38 (95% CI, 3.37 to 29.39, P=0.02). The average decrease in pain intensity from pre-RFA to 1-month follow-up was 26.9 (P<0.0001) and 14.2 for 3-month follow-up (P=0.02). The odds of being in lower pain severity at 1-month follow-up is 14.03 (95% CI, 2.33 to 25.73, P<0.0001) times higher than that at pre-RFA, and the odds at 3-month follow-up is 8.00 (95% CI, 0.85 to 15.15, P<0.001) times higher than that at pre-RFA. The average increase in mood from pre-RFA to 1-month follow-up was 19.9 (P<0.0001) and 14.9 for 3-month follow-up (P=0.005). Conclusion This cooperative group trial strongly suggests that RFA can safely palliate pain from bone metastases. PMID:20041484

  9. After insufficient radiofrequency ablation, tumor-associated endothelial cells exhibit enhanced angiogenesis and promote invasiveness of residual hepatocellular carcinoma

    PubMed Central

    2012-01-01

    Background The mechanism regarding rapid progression of residual hepatocellular carcinoma (HCC) after insufficient radiofrequency ablation (RFA) has been preliminarily discussed. However, most studies have mainly focused on RFA-induced changes in the tumor cells. The present study was designed to determine whether tumor-associated endothelial cells (TAECs) could contribute to the invasiveness of HCC after insufficient RFA. Methods TAECs were isolated from fresh HCC tissue and characterized. Morphological changes were observed in TAECs after heat treatment for 10 min. TAEC proliferation, migration and tube formation after heat treatment for 10 min at 37°C (control group), and 42 and 47°C (insufficient RFA groups) were examined. The differences in TAECs interactions with HepG2-GFP or HCCLM3-GFP cells among the two insufficient RFA groups and control group were evaluated. The expression of E-selectin, ICAM-1 and VCAM-1 in TAECs was measured. The effects of TAECs on the invasiveness of HepG2-GFP or HCCLM3-GFP cells after insufficient RFA were analyzed. The IL-6, IL-8, MCP-1 and GRO-α concentrations in conditioned medium from TAECs were measured after insufficient RFA. The associated signaling pathways of Akt, ERK1/2, STAT3 and NF-κB were analyzed in TAECs after insufficient RFA. Results TAECs expressed the EC-specific markers and took up complexes of Dil-Ac-LDL. Relative to the control group, the proliferation of TAECs was significantly inhibited and their migration and tube formation were significantly enhanced in the insufficient RFA groups. Significantly more HepG2-GFP or HCCLM3-GFP cells adhered to TACEs in these groups than in the control group (all P<0.001), via up-regulated expression of E-selectin, ICAM-1 and VCAM-1. TAECs promoted the invasiveness of HepG2-GFP or HCCLM3-GFP cells after insufficient RFA via the up-regulation of IL-6, IL-8, MCP-1 and GRO-α in conditioned medium (all P<0.05). Insufficient RFA enhanced the activities of Akt, ERK1/2 and NF

  10. Uterine Leiomyomas: Safety and Efficacy of US-guided Suprapubic Transvaginal Radiofrequency Ablation at 1-year Follow-up.

    PubMed

    Wu, Xiang-Jun; Guo, Qing; Cao, Bing-Sheng; Tan, Li-Xia; Zhang, Hong-Yu; Cai, Yu-Ru; Gao, Bu-Lang

    2016-06-01

    Purpose To assess the safety and efficacy of ultrasonography (US)-guided suprapubic transvaginal (ST) radiofrequency ablation (RFA) in the treatment of symptomatic uterine leiomyomas at 1-year follow-up. Materials and Methods The institutional review board approved this prospective study, and all patients provided informed consent. ST RFA was performed as an outpatient procedure 3 days after menstruation in 51 women (age range, 32-52 years; mean age, 42.2 years) with 62 leiomyomas. The leiomyomas were assessed with conventional and contrast material-enhanced US before and after ST RFA for leiomyoma size, location, and blood flow. All patients were evaluated for postoperative complications, including abdominal pain, injury to surrounding tissues and organs, vaginal bleeding, increased vaginal discharge, fever, dyspnea, and menorrhagia, after ST RFA and at follow-up visits. The leiomyoma volumes, improvement in leiomyoma-related symptoms, effect on quality of life (QOL), and patient satisfaction were assessed and compared before and after ST RFA and at follow-up visits by using statistical analyses. Results Sixty-two leiomyomas were successfully treated with ST RFA until 90% of the leiomyoma was echogenic. At 1-month follow-up, 46 (74%) leiomyomas had no contrast enhancement, five (8%) had peripheral enhancement, eight (13%) had focal enhancement, and three (5%) had scattered enhancement at contrast-enhanced US. At 6-month follow-up, the number of leiomyomas that had no enhancement, peripheral enhancement, focal enhancement, or scattered enhancement was 43 (69%), seven (11%), nine (15%), and three (5%), respectively. The leiomyoma volumes were significantly (P < .05) reduced at 1-, 3-, 6-, and 12-month follow-up (from 33.0 cm(3) ± 25.1 [standard deviation] before treatment to 6.8 cm(3) ± 7.7 at 12-month follow-up). The mean percentage volume reduction at 1-, 3-, 6-, and 12-month follow-up was 28%, 57%, 63%, and 78%, respectively. The scores for symptoms and QOL

  11. CT-Guided Radiofrequency Ablation of T1a Renal Cell Carcinoma in Korea: Mid-Term Outcomes

    PubMed Central

    Kim, Hae Jin; Park, Jung Jae; Kim, Chan Kyo

    2016-01-01

    Objective To evaluate the mid-term outcomes of percutaneous radiofrequency ablation (RFA) treatment in patients with small (< 4 cm) renal cell carcinoma (RCC) in Korea. Materials and Methods Between 2010 and 2015, 51 patients (40 men and 11 women; median age, 57 years) with biopsyproven 51 RCC were treated using CT-guided RFA. All patients were clinically staged T1aN0M0 prior to RFA. The median tumor size and follow-up period were 2.1 cm (range, 1.0–3.9 cm) and 26 months (4–60 months), respectively. Local tumor progression, distant metastasis, primary and secondary effectiveness rates, and major complication rates were recorded. Estimated glomerular filtration rates (GFRs) between pre-RFA and last follow-up were compared using paired t tests. The 2-year recurrence-free survival rate was calculated using Kaplan-Meier survival analysis. Results Of the 51 patients, 2 (3.9%) experienced local tumor progression, and 1 (2.0%) had lymph node metastasis after the first RFA session. Primary and secondary effectiveness rates were 96.1% (49/51) and 100% (1/1), respectively. Only 1 patient experienced a major complication (uretero-pelvic stricture) after the second RFA session for treating a local tumor progression, and the major complication rate was 1.9% (1/52). The median pre-RFA and last follow-up GFRs were 87.1 mL/ min/1.73 m2 (14.2–142.7 mL/min/1.73 m2) and 72.0 mL/min/1.73 m2 (7.2–112.6 mL/min/1.73 m2), respectively (p < 0.0001). The 2-year recurrence-free survival rate was 96.0%. Conclusion CT-guided RFA is a safe and effective treatment in Korean patients with T1a RCC because of excellent mid-term outcomes. PMID:27587966

  12. Treatment of liver cancer of middle and advanced stages using ultrasound-guided percutaneous ethanol injection combined with radiofrequency ablation: A clinical analysis

    PubMed Central

    SUN, XUE; LI, RU; ZHANG, BOTAO; YANG, YUEJIE; CUI, ZHIFEI

    2016-01-01

    Liver cancer is a malignancy of the digestive system and has a high morbidity and mortality rate. Local intervention has become a viable option in identifying liver treatment. The aim of the present study was to analyze the clinical effects of treating liver cancer in middle and advanced stages using ultrasound-guided percutaneous ethanol injection (PEI) in tumors combined with radiofrequency ablation (RFA). A total of 100 patients with stage III–IV liver cancers were selected to participate in the study. Patients were divided into groups. In group A, treatment was initiated with PEI and after 1–2 weeks RFA was applied while in group B treatment was initiated with RFA and after 1–2 weeks PEI was applied. Patients in group C received PEI and RFA simultaneously. The clinical effects in the 3 groups were compared after 6-month follow ups. The volume of tumor ablation necrosis in group A was significantly greater than that in the groups B and C, while the size was significantly smaller compared to groups B and C after ablation. For group A, the complete ablation rate was significantly higher than that in groups B and C, and the differences were statistically significant (P<0.05). Liver damage indices, including raising levels of glutamic-pyruvic transaminase and total bilirubin, were significantly decreased in group A (P<0.05). The survival rate in group A was also significantly higher than in groups B and C (P<0.05). In conclusion, for patients with liver cancer in middle and advanced stages, the treatment method using PEI followed by RFA was more beneficial in terms of improving the tumor ablation rate, alleviating liver damages and increasing survival rates. PMID:26998128

  13. Excessive radiofrequency application: effects on capsular tissue in an animal model.

    PubMed

    Wolf, Brian R; Heiner, Anneliese D; Albright, John P; Nepola, James V

    2005-01-01

    Capsular attenuation has been seen after thermal capsulorrhaphy surgery. The purpose of this study was to evaluate the mechanical, histologic, and morphologic effects on capsular tissue after cumulative applications of radiofrequency energy. Ovine patellofemoral capsular tissue was treated with 1, 2, 4, or 8 applications of bipolar radiofrequency energy and then analyzed. No acute capsular ablation or destruction was seen grossly, even in the 8-application group. No definitive visual clues that excessive radiofrequency energy had been applied were seen. There was significant shrinkage and loss of tensile stiffness for all thermal application groups. Given the small sample sizes, post-application failure load, percent relaxation, and stiffness were not observed to be significantly different among the groups. Cumulative applications produced minimal further tissue shrinkage but were accompanied by larger, though not statistically significant, mechanical property losses and increased depth of tissue penetration. These findings suggest that there is no benefit to repeated applications of radiofrequency energy to capsular tissue.

  14. Local recurrence of small cell lung cancer following radiofrequency ablation is induced by HIF-1α expression in the transition zone

    PubMed Central

    WAN, JUN; WU, WEI; ZHANG, RENQUAN

    2016-01-01

    Local recurrence of lung cancer following radiofrequency ablation (RFA) treatment is common. The aims of the present study were to assess how RFA treatment affects the growth of small cell lung cancer (SCLC) micrometastases in the transition zone (TZ) surrounding the ablated region and in the reference zones (RZs) of the ablated or unablated lobes and to identify the molecular mechanism(s) of lung cancer recurrence following RFA treatment. After lung micrometastases of human SCLCs had formed, RFA treatment was applied to the right upper lobe (RUL) of the lung in nude mice. Hypoxia inducible factor (HIF)-1α expression, proliferation and angiogenesis potential both in the TZ and RZ were evaluated over time. Separately, at day 1, 7 and 14 following RFA treatment, the growth of micrometastases showed an ~2-fold increase in the TZ compared to the RZ of the unablated lobe, as the right lower lobe (RLL) and the growth of micrometastases in the RZ of the RUL was also induced by RFA. In addition, accelerated tumor growth in the TZ was induced by HIF-1α, but was not associated with tissue angiogenesis potential. We concluded that local recurrences of SCLCs caused by overproliferation of micrometastases following RFA treatment were driven by HIF-1α, although angiogenesis was not the driving force in the TZ. PMID:26750332

  15. Influence of NaCl Concentrations on Coagulation, Temperature, and Electrical Conductivity Using a Perfusion Radiofrequency Ablation System: An Ex Vivo Experimental Study

    SciTech Connect

    Aube, Christophe Schmidt, Diethard; Brieger, Jens; Schenk, Martin; Kroeber, Stefan; Vielle, Bruno; Claussen, Claus D.; Goldberg, S. Nahum; Pereira, Philippe L.

    2007-02-15

    Purpose. To determine, by means of an ex vivo study, the effect of different NaCl concentrations on the extent of coagulation obtained during radiofrequency (RF) ablation performed using a digitally controlled perfusion device. Method. Twenty-eight RF ablations were performed with 40 W for 10 min using continuous NaCl infusion in fresh excised bovine liver. For perfusion, NaCl concentrations ranging from 0 (demineralized water) to 25% were used. Temperature, the amount of energy, and the dimensions of thermal-induced white coagulation were assessed for each ablation. These parameters were compared using the nonparametric Mann-Whitney test. Correlations were calculated according to the Spearman test. Results. RF ablation performed with 0.9% to 25% concentrations of NaCl produced a mean volume of coagulation of 30.7 {+-} 3.8 cm{sup 3}, with a mean short-axis diameter of 3.6 {+-} 0.2 cm. The mean amount of energy was 21,895 {+-} 1,674 W and the mean temperature was 85.4 {+-} 12.8 deg. C. Volume of coagulation, short-axis diameter, and amount of energy did not differ significantly among NaCl concentrations (p > 0.5). A correlation was found between the NaCl concentration and the short-axis diameter of coagulation (r = 0.64) and between the NaCl concentration and the mean temperature (r = 0.67), but not between the NaCl concentration and volume of coagulation. Conclusion. In an ex vivo model, continuous perfusion with high NaCl concentrations does not significantly improve the volume of thermal-induced coagulation. This may be because the use of a low-power generator cannot sufficiently exploit the potential advantage of better tissue conductivity provided by NaCl perfusion.

  16. Radiofrequency Ablation Combined with Renal Arterial Embolization for the Treatment of Unresectable Renal Cell Carcinoma Larger Than 3.5 cm: Initial Experience

    SciTech Connect

    Yamakado, Koichiro Nakatsuka, Atsuhiro; Kobayashi, Shigeki; Akeboshi, Masao; Takaki, Haruyuki; Kariya, Zentaro; Kinbara, Hiroyuki; Arima, Kiminobu; Yanagawa, Makoto; Hori, Yasuhide; Kato, Hiromi; Sugimura, Yoshiki; Takeda, Kan

    2006-06-15

    The purpose of the study was to evaluate the feasibility, safety, and therapeutic effects of the combination of renal arterial embolization and radiofrequency (RF) ablation to reinforce the anticancer effect on renal cell carcinomas (RCCs) measuring 3.5 cm or larger. This study was undertaken to evaluate this combined therapy on large RCCs-based tumor geometry. Eleven patients with 12 RCCs 3.5 cm or larger in diameter (3.5-9.0 cm) underwent combined therapy. Two were exophytic tumors, and the remaining 10 tumors had components extending into the renal sinus fat. Tumor vessels were selectively embolized in nine patients and the renal artery was completely embolized in two patients with polyvinyl alcohol or ethanol mixed with iodized oil. RF ablation was percutaneously done under the computed tomographic (CT)-fluoroscopic guidance. Response to treatment was evaluated by dynamic contrast-enhanced CT and magnetic resonance (MR) imaging. Tumor enhancement was eliminated after a single RF session in nine tumors (75%), after two sessions in two tumors (17%), and after four sessions in one tumor (8%). Both exophytic tumors (100%) and 7 of 10 tumors having components in the renal sinus fat (70%) were completely ablated with a single RF session. All tumors remained controlled during a mean follow-up period of 13 months and showed significant reduction in tumor sizes (5.2 {+-} 1.7 cm to 3.6 {+-} 1.4 cm, p < 0.001). A delayed abscess developed in the ablated lesion in a patient, which was percutaneously drainaged. Combined therapy as described in this report is a feasible, relatively safe, and promising treatment method for large RCCs regardless of tumor geometry.

  17. Radiofrequency ablation of metastatic chondrosarcoma-associated refractory ventricular tachycardia originating from the right ventricular outflow tract: A case report and literature review

    PubMed Central

    Shi, Xiangmin; Liang, Zhuo; Li, Jian; Guo, Jianping; Shan, Zhaoliang; Wang, Yutang

    2016-01-01

    Ventricular tachycardia (VT) and premature contraction originating from the right ventricular outflow tract (RVOT) usually appear in healthy individuals. Radiofrequency ablation (RFA) is highly effective at resolving this type of arrhythmia. Refractory VT of RVOT is uncommon and occasionally results from cardiac metastasis of extraskeletal mesenchymal chondrosarcomas (ESMC). ESMC is a rare malignant tumor arising from soft tissues. The current study presents the case of a 25-year-old male with severe VT arising from RVOT due to metastasis of an ESMC that originally occurred in the retroperitoneum. The diagnosis was confirmed following echocardiography and cardiac magnetic resonance. VT was eventually eliminated by RFA, and during the 8-month follow-up period the patient did not complain of any palpitations. Holter monitoring confirmed the absence of recurrence. PMID:27588097

  18. Metal contents of liver parenchyma after percutaneous ethanol injection or radiofrequency ablation in patients with hepatocellular carcinoma before and after trientine hydrochloride therapy.

    PubMed

    Fukuda, Hiroyuki; Ebara, Masaaki; Okabe, Shinichiro; Yoshikawa, Masaharu; Sugiura, Nobuyuki; Saisho, Hiromitsu; Kondo, Fukuo; Yukawa, Masae

    2004-06-01

    We administered trientine hydrochloride, a drug used in the treatment of Wilson's disease, to patients with hepatocellular carcinoma after radical treatment with percutaneous ethanol injection or radiofrequency ablation, and examined its effect on the reduction of liver-tissue copper content. We enrolled 24 patients with 3 or fewer primary lesions of Child class A or B hepatocellular carcinoma with diameters of 3 cm or less who had undergone radical treatment with percutaneous ethanol injection or radiofrequency ablation. Trientine hydrochloride was orally administered in a single daily dose of 250 mg to 12 patients before a meal (at fasting, group 1) or at a total daily dosage of 750 mg, divided into 3 doses, to 12 patients (group 2). This study was a randomized between-groups comparative study of 12 weeks' duration. We used the particle-induced x-ray-emission method to determine liver-tissue mineral content. Urine copper and serum mineral levels were also measured, and transaminase levels were examined. Liver-tissue copper content decreased significantly, to 160.1 microg/g dry weight, after treatment, compared with the pretreatment level of 306.8 microg/g dry weight (P <.05). We detected no significant difference in iron or zinc content before and after treatment. The copper content was significantly reduced after treatment in both groups (P <.05). The urine copper level was significantly increased after 1 week of treatment but decreased thereafter. Serum copper levels were significantly reduced after treatment (P <.01). We detected no significant difference in transaminase level before and after treatment. Iron-deficiency anemia in 1 patient after 12 weeks' treatment was the only adverse reaction, and it was improved by the administration of an iron product. We noted no other overt adverse reactions. In patients with hepatocellular carcinoma, trientine hydrochloride therapy may significantly reduce copper content in liver tissue.

  19. Percutaneous Radiofrequency Ablation of Osteoid Osteomas with Use of Real-Time Needle Guidance for Accurate Needle Placement: A Pilot Study

    SciTech Connect

    Busser, Wendy M. H. Hoogeveen, Yvonne L.; Veth, Rene P. H.; Schreuder, H. W. Bart; Balguid, Angelique; Renema, W. KlaasJan; SchultzeKool, Leo J.

    2011-02-15

    Purpose: To evaluate the accuracy and technical success of positioning a radiofrequency ablation (RFA) electrode in osteoid osteomas by use of a new real-time needle guidance technology combining cone-beam computed tomography (CT) and fluoroscopy. Materials and Methods: Percutaneous RFA of osteoid osteomas was performed in five patients (median age 18 years), under general anesthesia, with the use of cone-beam CT and fluoroscopic guidance for electrode positioning. The outcome parameters were technical success, meaning correct needle placement in the nidus; accuracy defined as the deviation (in mm) from the center of the nidus; and clinical outcome at follow-up. Results: In all five cases, positioning was possible within 3 mm of the determined target location (median nidus size 6.8 mm; range 5-10.2 mm). All procedures were technically successful. All patients were free of pain at clinical follow-up. No complications were observed. Conclusion: Real-time fluoroscopy needle guidance based on cone-beam CT is a useful tool to accurately position radiofrequency needles for minimally invasive treatment of osteoid osteomas.

  20. "One-off" complete radiofrequency ablation of hepatocellular carcinoma adjacent to the gallbladder by a novel laparoscopic technique without gallbladder isolation.

    PubMed

    Jiang, Kai; Su, Ming; Zhao, Xiangqian; Chen, Yongwei; Zhang, Wenzhi; Wang, Jing; Dong, Jiahong; Huang, Zhiqiang

    2014-04-01

    The main objective of this study is to assess the feasibility and safety of treating hepatocellular carcinoma (HCC) proximal to the gallbladder using laparoscopic radiofrequency ablation (RFA). Surgical ablation of tumor located adjacent to the gallbladder may damage the gallbladder wall, even with a laparoscope and this ablation method is not precise and incomplete and is frequently combined with alcohol injections with need for further RFA treatment. Four patients were included in this study, with typical HCC where the tumor was present on the left, right, or bed side surrounding the gallbladder. The gallbladder was not separated or removed during larascopic inspection. In the RFA treatment procedure, the tumor lesion was pre-heated for 10 min, and heating was continued for 20 min. The integrity of the gallbladder wall was properly maintained. A follow-up to check for possible local recurrence was carried out 1 year after the RFA. The goal of "one-off" tumor complete RFA is to achieve thorough ablation of the tumor in a single treatment and limiting the possibility of recurrence within 6 months. Seven days after RFA, liver functions of all the patients returned to near-preoperative levels. The patients experienced slight pain in the upper right abdomen, which disappeared in 2-3 days. Results of B ultrasound on days 3-5 showed thickening of the periphery of the ablation area, without significant effusion. Enhanced CT on day 3 showed that RFA low-density area completely covered the lesions. No significant abnormality was observed in the gallbladder and its vicinity. One month after the surgery, B ultrasound and CT examination revealed no significant abnormalities. All patients had an intact gallbladder, and no extrahepatic or intrahepatic bile duct dilatation occurred. There was no evidence of damage to the bile duct or the vessels. Follow-up for 18-32 months found that all patients were in good condition. "One-off" complete RFA can be safely implemented to ablate

  1. Larger low voltage zone in endocardial unipolar map compared with that in epicardial bipolar map indicates difficulty in eliminating ventricular tachycardia by catheter ablation.

    PubMed

    Miyamoto, Koji; Noda, Takashi; Satomi, Kazuhiro; Wada, Mitsuru; Nakajima, Ikutaro; Ishibashi, Kohei; Okamura, Hideo; Noguchi, Teruo; Anzai, Toshihisa; Yasuda, Satoshi; Ogawa, Hisao; Shimizu, Wataru; Aiba, Takeshi; Kamakura, Shiro; Kusano, Kengo

    2016-08-01

    Patients with ischemic and non-ischemic cardiomyopathy often have substrate for ventricular tachycardia (VT) in the endocardium (ENDO), epicardium (EPI), and/or intramural. Although it has been reported that the ENDO unipolar (UNI) voltage map is useful in detecting EPI substrate, its feasibility to detect intramural scarring and its usefulness in radiofrequency catheter ablation (RFCA) remain unclear. To assess the relationship between the left ventricle (LV) ENDO UNI voltage map and the LV EPI bipolar (BIP) voltage map, and to determine the usefulness of the ENDO UNI voltage map to guide RFCA for VT in patients with cardiomyopathy undergoing combined ENDO- and EPI RFCA. Eleven patients with VT undergoing detailed ENDO and EPI electroanatomical mapping of the LV were included (mean age 59 ± 11 years, 9 men). We assessed the value of the LV ENDO UNI voltage map in identifying EPI and/or intramural substrate in these 11 patients with non-ischemic or ischemic cardiomyopathy. The underlying heart disease was dilated cardiomyopathy in 4 patients, cardiac sarcoidosis in 3, hypertrophic cardiomyopathy in 2, and ischemic heart disease in 2 patients. The mean LV ejection fraction was 24 ± 7 %. The low voltage zone (LVZ) was defined as <1.5 mV for LV ENDO BIP electrograms (EGMs), <8.3 mV for LV ENDO UNI EGMs, and <1.0 mV for LV EPI BIP EGMs. The surface area of each LVZ was measured. We also measured the LVZ of the spatial overlap between ENDO UNI and EPI BIP voltage maps using the transparency mode on CARTO software. We performed RFCA at the ENDO and EPI based on activation and/or substrate maps, targeting the LVZ and/or abnormal EGMs. The LVZ was present in the LV ENDO BIP voltage map in 10 of 11 patients (42 ± 33 cm(2)), and in the LV ENDO UNI voltage map in 10 of 11 patients (72 ± 45 cm(2)). The LVZ was present in the EPI BIP voltage map in 9 of 11 patients (70 ± 61 cm(2)), and the LVZ in the ENDO UNI voltage map was also seen in all 9 patients

  2. Larger low voltage zone in endocardial unipolar map compared with that in epicardial bipolar map indicates difficulty in eliminating ventricular tachycardia by catheter ablation.

    PubMed

    Miyamoto, Koji; Noda, Takashi; Satomi, Kazuhiro; Wada, Mitsuru; Nakajima, Ikutaro; Ishibashi, Kohei; Okamura, Hideo; Noguchi, Teruo; Anzai, Toshihisa; Yasuda, Satoshi; Ogawa, Hisao; Shimizu, Wataru; Aiba, Takeshi; Kamakura, Shiro; Kusano, Kengo

    2016-08-01

    Patients with ischemic and non-ischemic cardiomyopathy often have substrate for ventricular tachycardia (VT) in the endocardium (ENDO), epicardium (EPI), and/or intramural. Although it has been reported that the ENDO unipolar (UNI) voltage map is useful in detecting EPI substrate, its feasibility to detect intramural scarring and its usefulness in radiofrequency catheter ablation (RFCA) remain unclear. To assess the relationship between the left ventricle (LV) ENDO UNI voltage map and the LV EPI bipolar (BIP) voltage map, and to determine the usefulness of the ENDO UNI voltage map to guide RFCA for VT in patients with cardiomyopathy undergoing combined ENDO- and EPI RFCA. Eleven patients with VT undergoing detailed ENDO and EPI electroanatomical mapping of the LV were included (mean age 59 ± 11 years, 9 men). We assessed the value of the LV ENDO UNI voltage map in identifying EPI and/or intramural substrate in these 11 patients with non-ischemic or ischemic cardiomyopathy. The underlying heart disease was dilated cardiomyopathy in 4 patients, cardiac sarcoidosis in 3, hypertrophic cardiomyopathy in 2, and ischemic heart disease in 2 patients. The mean LV ejection fraction was 24 ± 7 %. The low voltage zone (LVZ) was defined as <1.5 mV for LV ENDO BIP electrograms (EGMs), <8.3 mV for LV ENDO UNI EGMs, and <1.0 mV for LV EPI BIP EGMs. The surface area of each LVZ was measured. We also measured the LVZ of the spatial overlap between ENDO UNI and EPI BIP voltage maps using the transparency mode on CARTO software. We performed RFCA at the ENDO and EPI based on activation and/or substrate maps, targeting the LVZ and/or abnormal EGMs. The LVZ was present in the LV ENDO BIP voltage map in 10 of 11 patients (42 ± 33 cm(2)), and in the LV ENDO UNI voltage map in 10 of 11 patients (72 ± 45 cm(2)). The LVZ was present in the EPI BIP voltage map in 9 of 11 patients (70 ± 61 cm(2)), and the LVZ in the ENDO UNI voltage map was also seen in all 9 patients

  3. Radiofrequency ablation versus surgical resection for the treatment of hepatocellular carcinoma conforming to the Milan criteria: systemic review and meta-analysis.

    PubMed

    Yi, Hui-Ming; Zhang, Wei; Ai, Xi; Li, Kai-Yan; Deng, You-Bin

    2014-01-01

    Radiofrequency ablation (RFA) is a promising ablation technique and has become one of the best alternatives for hepatocellular carcinoma (HCC) patients. But whether RFA or surgical resection (SR) is the better treatment for HCC conforming to the Milan criteria has long been debated. A meta-analysis of trials that compared RFA versus SR was conducted regarding the survival rate and recurrence rate. Pooled odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using fixed or random effects models. Nineteen studies, comprising 2 randomized controlled trials and 17 non-randomized controlled trials, were included with a total of 2895 patients. The 5 years overall survival rate for SR group was significantly higher than that for RFA group. In the SR group, the local recurrence rate was significantly lower when compared with the RFA group. This meta-analysis yielded no significant differences between laparoscopic RFA and SR in 5-year overall survival rate. In conclusion, surgical resection remains the better choice of treatment for HCC conforming to the Milan criteria, whereas RFA should be considered as an effective alternative treatment when surgery is not feasible. As for RFA technique, laparoscopic approach may be more effective than percutaneous approach for HCC conforming to Milan criteria.

  4. Radiofrequency ablation versus surgical resection for the treatment of hepatocellular carcinoma conforming to the Milan criteria: systemic review and meta-analysis

    PubMed Central

    Yi, Hui-Ming; Zhang, Wei; Ai, Xi; Li, Kai-Yan; Deng, You-Bin

    2014-01-01

    Radiofrequency ablation (RFA) is a promising ablation technique and has become one of the best alternatives for hepatocellular carcinoma (HCC) patients. But whether RFA or surgical resection (SR) is the better treatment for HCC conforming to the Milan criteria has long been debated. A meta-analysis of trials that compared RFA versus SR was conducted regarding the survival rate and recurrence rate. Pooled odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using fixed or random effects models. Nineteen studies, comprising 2 randomized controlled trials and 17 non-randomized controlled trials, were included with a total of 2895 patients. The 5 years overall survival rate for SR group was significantly higher than that for RFA group. In the SR group, the local recurrence rate was significantly lower when compared with the RFA group. This meta-analysis yielded no significant differences between laparoscopic RFA and SR in 5-year overall survival rate. In conclusion, surgical resection remains the better choice of treatment for HCC conforming to the Milan criteria, whereas RFA should be considered as an effective alternative treatment when surgery is not feasible. As for RFA technique, laparoscopic approach may be more effective than percutaneous approach for HCC conforming to Milan criteria. PMID:25419346

  5. Radiofrequency and microwave ablation in combination with transarterial chemoembolization induce equivalent histopathologic coagulation necrosis in hepatocellular carcinoma patients bridged to liver transplantation

    PubMed Central

    Ginsburg, Michael; Ahmed, Osman; Doshi, Taral; Hart, John; Te, Helen; Van Ha, Thuong Gustav

    2016-01-01

    Background Bridging therapy plays an increasingly important role in the management of patients with hepatocellular carcinoma (HCC) awaiting liver transplantation (LT). Combination therapy with drug-eluting bead transarterial chemoembolization (DEB-TACE) and percutaneous thermal ablation, such as radiofrequency ablation (RFA) or microwave ablation (MWA), has shown success at prolonging survival and bridging patients to LT. However, few studies have evaluated the two combination therapy regimens head-to-head at a single institution, and fewer have compared histopathology. This retrospective study compares tumor coagulation on explanted livers in patients with HCC treated with DEB-TACE sequentially combined with RFA versus MWA. Methods From 2005 to 2015, 42 sequential patients underwent combination therapy prior to LT by Milan criteria, with 11 patients (11 tumors; mean, 2.9 cm; range, 1.8–4.3 cm) in the DEB-TACE/RFA cohort and 31 patients (40 tumors; mean, 2.4 cm; range, 1.1–5.4 cm) in the DEB-TACE/MWA cohort. The mean TACE procedures in the RFA and MWA cohorts were 1.3 (range, 1–2) and 1.3 (range, 1–3), respectively. The mean thermal ablations in the RFA and MWA cohorts were 1.2 (range, 1–2) and 1.3 (range, 1–3), respectively. Tumor coagulation was evaluated on explanted livers. Results Mean tumor coagulation in the RFA and MWA cohorts were 88.9% (range, 0–100%) and 90.5% (range, 30–100%), respectively (P=0.82). Rates of complete tumor coagulation in the RFA and MWA cohorts were 45% and 53%, respectively (P=0.74). No difference in tumor coagulation was found between the cohorts when separating tumors <3 cm (P=0.21) and >3 cm (P=0.09). Among all 51 tumors, the 36 in complete response (CR) on imaging at LT demonstrated mean tumor coagulation of 95.8%. No correlation was found between tumor coagulation and initial tumor size or time interval to LT. No tumor seeding was seen along the ablation tracts. Conclusions RFA and MWA in sequential combination

  6. Acute success and short-term follow-up of catheter ablation of isthmus-dependent atrial flutter; a comparison of 8 mm tip radiofrequency and cryothermy catheters

    PubMed Central

    Janse, P.; Alings, M.; Scholten, M. F.; Mekel, J. M.; Miltenburg, M.; Jessurun, E.; Jordaens, L.

    2008-01-01

    Objectives To compare the acute success and short-term follow-up of ablation of atrial flutter using 8 mm tip radiofrequency (RF) and cryocatheters. Methods Sixty-two patients with atrial flutter were randomized to RF or cryocatheter (cryo) ablation. Right atrial angiography was performed to assess the isthmus. End point was bidirectional isthmus block on multiple criteria. A pain score was used and the analgesics were recorded. Patients were followed for at least 3 months. Results The acute success rate for RF was 83% vs 69% for cryo (NS). Procedure times were similar (mean 144 ± 48 min for RF, vs 158 ± 49 min for cryo). More applications were given with RF than with cryo (26 ± 17 vs. 18 ± 10, p < 0.05). Fluoroscopy time was longer with RF (29 ± 15 vs. 19 ± 12 min, p < 0.02). Peak CK, CK-MB and CK-MB mass were higher, also after 24 h in the cryo group. Troponin T did not differ. Repeated transient block during application (usually with cryoablation) seemed to predict failure. Cryothermy required significantly less analgesia (p < 0.01), and no use of long sheaths (p < 0.005). The isthmus tended to be longer in the failed procedures (p = 0.117). This was similar for both groups, as was the distribution of anatomic variations. Recurrences and complaints in the successful patients were similar for both groups, with a very low recurrence of atrial flutter after initial success. Conclusions In this randomized study there was no statistical difference but a trend to less favorable outcome with 8 mm tip cryocatheters compared to RF catheters for atrial flutter ablation. Cryoablation was associated with less discomfort, fewer applications, shorter fluoroscopy times and similar procedure times. The recurrence rate was very low. Cryotherapy can be considered for atrial flutter ablation under certain circumstances especially when it has been used previously in the same patient, such as in an AF ablation. PMID:18363087

  7. Effectiveness of ultrasound-guided radiofrequency ablation in the treatment of 36 renal cell carcinoma tumours compared with published results of using computed tomography guidance.

    PubMed

    Davis, Kellie; Kielar, Ania; Jafari, Katayoun

    2012-08-01

    This study aimed to analyse the outcomes of ultrasound (US) guided radiofrequency ablation (RFA) in patients with renal lesions and to compare our outcomes with published results of ablations carried out when using computed tomography (CT) guidance. This retrospective study evaluated RFA of 36 renal tumours in 32 patients (M = 21, F = 11). The mean patient age was 70 years (range, 39-89 years). Ablations were performed by using either multi-tined applicators or cooled and/or cluster applicators under US guidance. Applicator size varied from 2-5 cm, depending on the size of the index tumour. Conscious sedation was administered by an anesthetist. Follow-up imaging by using contrast-enhanced CT was performed 1, 3, 6, and 12 months after RFA, and yearly thereafter. The mean tumour follow-up time was 12 months (range, 1-35 months). The mean tumour size was 2.7 cm (range, 1-5 cm). Primary effectiveness was achieved in 31 cases (86.1%), with patients in 5 cases (11.1%) demonstrating residual disease. Three patients had repeated sessions, which were technically successful. The remaining 2 patients were not re-treated because of patient comorbidities. As a result, secondary effectiveness was achieved in 34 patients (94.4%). In 1 patient, a new lesion developed in the same kidney but remote from the 2 prior areas of treatment. Hydrodissection was performed in 3 patients (8.3%), manipulation or electrode repositioning in 11 patients (30.6%), and ureteric cooling in 1 patient (2.8%). Minor and major complications occurred in 3 (8.3%) and 3 (8.3%) patients, respectively. Correlation coefficients were calculated for distance from skin to tumour and risk of complication as well as compared with primary and secondary effectiveness. This study demonstrates that US-guided RFA is an effective treatment for renal lesions, with rates of effectiveness and complication rates comparable with published CT-guided RFA results.

  8. Percutaneous Radiofrequency Ablation of Painful Spinal Tumors Adjacent to the Spinal Cord with Real-Time Monitoring of Spinal Canal Temperature: A Prospective Study

    SciTech Connect

    Nakatsuka, Atsuhiro Yamakado, Koichiro; Takaki, Haruyuki; Uraki, Junji; Makita, Masashi; Oshima, Fumiyoshi; Takeda, Kan

    2009-01-15

    PurposeTo prospectively evaluate the feasibility, safety, and clinical utility of bone radiofrequency (RF) ablation with real-time monitoring of the spinal canal temperature for the treatment of spinal tumors adjacent to the spinal cord.Materials and MethodsOur Institutional Review Board approved this study. Patients gave informed consent. The inclusion criteria were (a) a painful spinal metastasis and (b) a distance of 1 cm or less between the metastasis and the spinal cord. The thermocouple was placed in the spinal canal under CT fluoroscopic guidance. When the spinal canal temperature reached 45{sup o}C, RF application was immediately stopped. RF ablation was considered technically successful when the procedure was performed without major complications. Clinical success was defined as a fall in the visual analogue scale score of at least 2 points.ResultsTen patients with spinal tumors measuring 3-8 cm (mean, 4.9 {+-} 1.5 cm) were enrolled. The distance between the tumor and the spinal cord was 1-6 mm (mean, 2.4 {+-} 1.6 mm). All procedures were judged technically successful (100%). The spinal canal temperature did not exceed 45{sup o}C in 9 of the 10 patients (90%). In the remaining patient, the temperature rose to 48{sup o}C, resulting in transient neural damage, although RF application was immediately stopped when the temperature reached 45{sup o}C. Clinical success was achieved within 1 week in all patients (100%).ConclusionBone RF ablation with real-time monitoring of the spinal canal temperature is feasible, safe, and clinically useful for the treatment of painful spinal metastases adjacent to the spinal cord.

  9. Influence of the Dermis Thickness on the Results of the Skin Treatment with Monopolar and Bipolar Radiofrequency Currents

    PubMed Central

    2016-01-01

    Electrically layered tissue structure significantly modifies distribution of radiofrequency (RF) current in the dermis and in the subcutaneous adipose tissue comparing to that in a homogeneous medium. On the basis of the simple model of RF current distribution in a two-layer skin containing dermis and subcutis, we assess the influence of the dermal thickness on the current density in different skin layers. Under other equal conditions, current density in the dermis is higher for the skin having thinner dermis. This contradicts the main paradigm of the RF theory stating that treatment results are mainly dependent on the maximal temperature reached in a target tissue, since the best short- and long-term clinical results of RF application to the skin were reported in the areas having thicker dermis. To resolve this contradiction, it is proposed that the long-term effect of RF can be realized through a structural modification of the subcutaneous fat depot adjacent to the treated skin area. Stimulation of these cells located near the interface dermis/subcutis will demand the concentration of applied RF energy in this area and will require the optimal arrangement of RF electrodes on the skin surface. PMID:27493952

  10. Combination radiofrequency (RF) ablation and IV liposomal heat shock protein suppression: Reduced tumor growth and increased animal endpoint survival in a small animal tumor model

    PubMed Central

    Yang, Wei; Ahmed, Muneeb; Tasawwar, Beenish; Levchenko, Tatynana; Sawant, Rupa R.; Torchilin, Vladimir; Goldberg, S. Nahum

    2012-01-01

    Background To investigate the effect of IV liposomal quercetin (a known down-regulator of heat shock proteins) alone and with liposomal doxorubicin on tumor growth and end-point survival when combined with radiofrequency (RF) tumor ablation in a rat tumor model. Methods Solitary subcutaneous R3230 mammary adenocarcinoma tumors (1.3–1.5 cm) were implanted in 48 female Fischer rats. Initially, 32 tumors (n=8, each group) were randomized into four experimental groups: (a) conventional monopolar RF alone (70°C for 5 min), (b) IV liposomal quercetin alone (1 mg/kg), (c) IV liposomal quercetin followed 24hr later with RF, and (d) no treatment. Next, 16 additional tumors were randomized into two groups (n=8, each) that received a combined RF and liposomal doxorubicin (15 min post-RF, 8 mg/kg) either with or without liposomal quercetin. Kaplan-Meier survival analysis was performed using a tumor diameter of 3.0 cm as the defined survival endpoint. Results Differences in endpoint survival and tumor doubling time among the groups were highly significant (P<0.001). Endpoint survivals were 12.5±2.2 days for the control group, 16.6±2.9 days for tumors treated with RF alone, 15.5±2.1days for tumors treated with liposomal quercetin alone, and 22.0±3.9 days with combined RF and quercetin. Additionally, combination quercetin/RF/doxorubicin therapy resulted in the longest survival (48.3±20.4 days), followed by RF/doxorubicin (29.9±3.8 days). Conclusions IV liposomal quercetin in combination with RF ablation reduces tumor growth rates and improves animal endpoint survival. Further increases in endpoint survival can be seen by adding an additional anti-tumor adjuvant agent liposomal doxorubicin. This suggests that targeting several post-ablation processes with multi-drug nanotherapies can increase overall ablation efficacy. PMID:22230341

  11. Minimal Use of Fluoroscopy to Reduce Fetal Radiation Exposure during Radiofrequency Catheter Ablation of Maternal Supraventricular Tachycardia

    PubMed Central

    Raman, Ajay Sundara; Hariharan, Ramesh

    2015-01-01

    Electrophysiologic procedures in the young engender concern about the potential long-term effects of radiation exposure. This concern is manifold if such procedures are contemplated during pregnancy. Catheter ablations in pregnancy are indicated only in the presence of an unstable tachycardia that cannot be controlled by antiarrhythmic agents. This report describes the case of an 18-year-old pregnant woman and our stratagem to minimize irradiation of the mother and the fetus. PMID:25873828

  12. Minimal use of fluoroscopy to reduce fetal radiation exposure during radiofrequency catheter ablation of maternal supraventricular tachycardia.

    PubMed

    Raman, Ajay Sundara; Sharma, Saumya; Hariharan, Ramesh

    2015-04-01

    Electrophysiologic procedures in the young engender concern about the potential long-term effects of radiation exposure. This concern is manifold if such procedures are contemplated during pregnancy. Catheter ablations in pregnancy are indicated only in the presence of an unstable tachycardia that cannot be controlled by antiarrhythmic agents. This report describes the case of an 18-year-old pregnant woman and our stratagem to minimize irradiation of the mother and the fetus. PMID:25873828

  13. The Feasibility of Using Thermal Strain Imaging to Regulate Energy Delivery During Intracardiac Radio-Frequency Ablation

    PubMed Central

    Seo, Chi Hyung; Stephens, Douglas N.; Cannata, Jonathan; Dentinger, Aaron; Lin, Feng; Park, Suhyun; Wildes, Douglas; Thomenius, Kai E.; Chen, Peter; Nguyen, Tho; de La Rama, Alan; Jeong, Jong Seob; Mahajan, Aman; Shivkumar, Kalyanam; Nikoozadeh, Amin; Oralkan, Omer; Truong, Uyen; Sahn, David J.; Khuri-Yakub, Pierre T.; O’Donnell, Matthew

    2011-01-01

    A method is introduced to monitor cardiac ablative therapy by examining slope changes in the thermal strain curve caused by speed of sound variations with temperature. The sound speed of water-bearing tissue such as cardiac muscle increases with temperature. However, at temperatures above about 50°C, there is no further increase in the sound speed and the temperature coefficient may become slightly negative. For ablation therapy, an irreversible injury to tissue and a complete heart block occurs in the range of 48 to 50°C for a short period in accordance with the well-known Arrhenius equation. Using these two properties, we propose a potential tool to detect the moment when tissue damage occurs by using the reduced slope in the thermal strain curve as a function of heating time. We have illustrated the feasibility of this method initially using porcine myocardium in vitro. The method was further demonstrated in vivo, using a specially equipped ablation tip and an 11-MHz microlinear intracardiac echocardiography (ICE) array mounted on the tip of a catheter. The thermal strain curves showed a plateau, strongly suggesting that the temperature reached at least 50°C. PMID:21768025

  14. Cost-Effectiveness Analysis of Stereotactic Body Radiotherapy and Radiofrequency Ablation for Medically Inoperable, Early-Stage Non-Small Cell Lung Cancer

    SciTech Connect

    Sher, David J.

    2011-12-01

    Purpose: The standard management of medically inoperable Stage I non-small-cell lung cancer (NSCLC) conventionally has been fractionated three-dimensional conformal radiation therapy (3D-CRT). The relatively poor local control rate and inconvenience associated with this therapy have prompted the development of stereotactic body radiotherapy (SBRT), a technique that delivers very high doses of irradiation typically over 3 to 5 sessions. Radiofrequency ablation (RFA) has also been investigated as a less costly, single-day therapy that thermally ablates small, peripheral tumors. The cost-effectiveness of these three techniques has never been compared. Methods and Materials: We developed a Markov model to describe health states of 65-year-old men with medically inoperable NSCLC after treatment with 3D-CRT, SBRT, and RFA. Given their frail state, patients were assumed to receive supportive care after recurrence. Utility values, recurrence risks, and costs were adapted from the literature. Sensitivity analyses were performed to model uncertainty in these parameters. Results: The incremental cost-effectiveness ratio for SBRT over 3D-CRT was $6,000/quality-adjusted life-year, and the incremental cost-effectiveness ratio for SBRT over RFA was $14,100/quality-adjusted life-year. One-way sensitivity analysis showed that the results were robust across a range of tumor sizes, patient utility values, and costs. This result was confirmed with probabilistic sensitivity analyses that varied local control rates and utilities. Conclusion: In comparison to 3D-CRT and RFA, SBRT was the most cost-effective treatment for medically inoperable NSCLC over a wide range of treatment and disease assumptions. On the basis of efficacy and cost, SBRT should be the primary treatment approach for this disease.

  15. Radiofrequency Ablation is Associated with Decreased Neoplastic Progression in Patients with Barrett’s Esophagus and Confirmed Low-Grade Dysplasia

    PubMed Central

    Small, Aaron J.; Araujo, James L.; Leggett, Cadman L.; Mendelson, Aaron H.; Agarwalla, Anant; Abrams, Julian A.; Lightdale, Charles J.; Wang, Timothy C.; Iyer, Prasad G.; Wang, Kenneth K.; Rustgi, Anil K.; Ginsberg, Gregory G.; Forde, Kimberly A.; Gimotty, Phyllis A.; Lewis, James D.; Falk, Gary W.; Bewtra, Meenakshi

    2015-01-01

    Background & Aims Barrett’s esophagus (BE) with low-grade dysplasia (LGD) can progress to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) has been shown to be an effective treatment for LGD in clinical trials but its effectiveness in clinical practice is unclear. We compared the rate of progression of LGD following RFA to that with endoscopic surveillance alone in routine clinical practice. Methods We performed a retrospective study of patients who either underwent RFA (n=45) or surveillance endoscopy (n=125) for LGD, confirmed by at least 1 expert pathologist, from October 1992 through December 2013 at 3 medical centers in the US. Cox regression analysis was used to assess the association between progression and RFA. Results Data were collected over median follow-up periods of 889 days (inter-quartile range, 264–1623 days) after RFA and 848 days (inter-quartile range, 322–2355 days) after surveillance endoscopy (P=.32). The annual rates of progression to HGD or EAC was 6.6% in the surveillance group and 0.77% in the RFA group. The risk of progression to HGD or EAC was significantly lower among patients who underwent RFA than those who underwent surveillance (adjusted hazard ratio, 0.06; 95% confidence interval, 0.008–0.48). Conclusions Among patients with BE and confirmed LGD, rates of progression to a combined endpoint of HGD and EAC were lower among those treated with RFA than among untreated patients. Although selection bias cannot be excluded, these findings provide additional evidence for the use of endoscopic ablation therapy for LGD. PMID:25917785

  16. Radiofrequency Catheter Ablation Improves the Quality of Life Measured with a Short Form-36 Questionnaire in Atrial Fibrillation Patients: A Systematic Review and Meta-Analysis

    PubMed Central

    Choi, Jong-Il; Kim, Young-Hoon

    2016-01-01

    Background The main purpose of performing radiofrequency catheter ablation (RFCA) in atrial fibrillation (AF) patients is to improve the quality of life (QoL) and alleviate AF-related symptoms. We aimed to determine the qualitative and quantitative effects of RFCA on the QoL in AF patients. Methods We performed a systemic review and meta-analysis using a random effects model. We searched for the studies that reported the physical component summary score (PCS) and mental component summary score (MCS) of the short form-36, a validated system to assess and quantify the QoL, before and after RFCA in AF patients. PCS and MCS are T-scores with a mean of 50 and standard deviation of 10. Results Of the 470 studies identified through systematic search, we included 13 studies for pre-RFCA vs. the post-RFCA analysis and 5 studies for treatment success vs. AF recurrence analyses. In the pre-RFCA vs. post-RFCA analysis, RFCA was associated with a significant increase in both the PCS (weighted mean difference [WMD] = 6.33 [4.81–7.84]; p < 0.001) and MCS (WMD = 7.80 [6.15–9.44]; p < 0.001). The ΔPCS (post-RFCA PCS–pre-RFCA PCS) and ΔMCS values were used for the treatment success vs. AF recurrence analysis. Patients with successful ablation had a higher ΔPCS (WMD = 7.46 [4.44–10.49]; p < 0.001) and ΔMCS (WMD = 7.59 [4.94–10.24]; p < 0.001). Conclusions RFCA is associated with a significant increase in the PCS and MCS in AF patients. Patients without AF recurrence after RFCA had a better improvement in the PCS and MCS than patients who had AF recurrence. PMID:27681507

  17. Impact of Impaired Renal Function on the Incidence of Atrial Fibrillation following Radiofrequency Ablation of Cavotricuspid Isthmus-Dependent Atrial Flutter

    PubMed Central

    Kwon, Chang Hee; Kim, Min Su; Roh, Jae-Hyung; Choi, Jin Hee; Jo, Uk; Lee, Woo Seok; Kim, Yoo Ri; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho

    2015-01-01

    Background and Objectives Atrial fibrillation (AF) occurs frequently after successful radiofrequency ablation (RFA) of cavotricuspid isthmus-dependent atrial flutter (CTI-AFL). Renal impairment has been implicated in the development of AF. The purpose of this study is to clarify the impact of impaired renal function on the incidence of AF after RFA of CTI-AFL. Subjects and Methods Between January 2001 and December 2013, 240 non-dialysis patients with no prior history of AF {mean age 55.9±15.2 years old; male, 192 (80.0%)} who had undergone successful CTI-AFL ablation were included in the present study. The baseline estimated glomerular filtration rate was calculated, and patients were divided into those with impaired renal function (<60 mL/min/1.73 m2) and those with preserved renal function (≥ 60 mL/min/1.73 m2). The incidence of AF was retrospectively analyzed. Results 69 (28.8%) patients experienced new onset AF during a median follow-up duration of 26 months (inter-quartile, 7-53). The incidence of AF was significantly higher in patients with impaired renal function than in those with preserved renal function {13/25 (52.0%) versus 56/215 (26.0%), log rank p=0.019}. Age, CHADS2 score, impaired renal function, and left atrial diameter were significantly associated with the incidence of AF in univariate Cox regression analysis. Multivariate analysis showed that age was the only significant predictor of AF incidence (hazard ratio, 1.024; 95% confidence interval, 1.004-1.044, p=0.020). Conclusion Patients with impaired renal function may require careful attention for the incidence of new onset AF following successful RFA of CTI-AFL. PMID:26617649

  18. [New techniques of tumor ablation (microwaves, electroporation)].

    PubMed

    de Baere, T

    2011-09-01

    Since the introduction of radiofrequency tumor ablation of liver tumors in the late 1990s, local destructive therapies have been applied to lung, renal and bone lesions. In addition, new techniques have been introduced to compensate for the limitations of radiofrequency ablation, namely the reduced rate of complete ablation for tumors larger than 3 cm and tumors near vessels larger than 3 mm. Microwave ablation is currently evolving rapidly. While it is a technique based on thermal ablation similar to radiofrequency ablation, there are significant differences between both techniques. Electroporation, of interest because of the non-thermal nature of the ablation process, also is under evaluation.

  19. Switching Monopolar Radiofrequency Ablation Using a Separable Cluster Electrode in Patients with Hepatocellular Carcinoma: A Prospective Study

    PubMed Central

    Choi, Jin Woo; Lee, Jeong Min; Lee, Dong Ho; Yoon, Jeong-Hee; Suh, Kyung-Suk; Yoon, Jung-Hwan; Kim, Yoon Jun; Lee, Jeong-Hoon; Yu, Su Jong; Han, Joon Koo

    2016-01-01

    Objective This study was conducted to evaluate the outcomes of multi-channel switching RFA using a separable cluster electrode in patients with HCC. Methods From November 2011 to July 2013, 79 patients with 98 HCCs < 5 cm were enrolled and treated with RFA using a multi-channel switching radiofrequency system and a separable cluster electrode under the guidance of a real-time fusion imaging system. The primary and secondary endpoints were the 3-year local tumor progression (LTP) rate and recurrence-free survival (RFS) rate, respectively. For post hoc analyses, LTP, RFS, and major complication rates were retrospectively compared with a historical control group treated with RFA using the same radiofrequency system but with multiple internally-cooled electrodes. Results The technique success rate of the 98 tumors was 100%. Cumulative 1-year, 2-year, and 3-year LTP rates were 3.4%, 6.9%, and 12.4%, respectively. For patient-level data, cumulative 1-year, 2-year, and 3-year RFS rates were 83.9%, 68.6%, and 45.4%, respectively. On post hoc analyses, none of the baseline characteristics showed a significant difference between the separable cluster electrode and multiple internally-cooled electrodes group. Cumulative LTP and RFS rates of the two groups also showed no significant difference (p = 0.401 and p = 0.881, respectively). Finally, major complication rates of the separable cluster electrode group (5.0%, 4/79) and multiple internally-cooled electrodes group (5.9%, 4/74) were also comparable (p = 1.000). Conclusion Switching monopolar RFA using a separable cluster electrode is a feasible and efficient technique for the treatment of HCCs smaller than 5 cm, providing comparable local tumor control to multiple internally-cooled electrodes. Trial Registration ClinicalTrials.gov NCT02745483 PMID:27575787

  20. Serum inflammatory factors and circulating immunosuppressive cells are predictive markers for efficacy of radiofrequency ablation in non-small-cell lung cancer.

    PubMed

    Schneider, T; Sevko, A; Heussel, C P; Umansky, L; Beckhove, P; Dienemann, H; Safi, S; Utikal, J; Hoffmann, H; Umansky, V

    2015-06-01

    In recent years, percutaneous radiofrequency ablation (RFA) has been developed as a new tool in the treatment of non-small-cell lung cancer (NSCLC) in non-surgical patients. There is growing evidence that RFA-mediated necrosis can modulate host immune responses. Here we analysed serum inflammatory factors as well as immunosuppressive cells in the peripheral blood to discover possible prognostic indicators. Peripheral blood and serum samples were collected before RFA and within 3 months after the treatment in a total of 12 patients. Inflammatory cytokines and growth factors were measured in serum by the Bio-Plex assay. Myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs ) were evaluated in the peripheral blood via flow cytometry. In patients developing local or lymphogenic tumour relapse (n=4), we found an early significant increase in the concentration of tumour necrosis factor (TNF)-α as well as chemokine (C-C motif) ligand (CCL)-2 and CCL-4 compared to patients without relapse (n=4) and healthy donors (n=5). These changes were associated with an elevated activity of circulating MDSC indicated by an increased nitric oxide (NO) production in these cells. Elevated serum levels of TNF-α, CCL-2 and CCL-4 associated with an increased NO production in circulating MDSCs might be an early indicator of the incomplete RFA and subsequently a potential tumour relapse in NSCLC.

  1. Survival of Patients with Hepatocellular Carcinoma (HCC) Treated by Percutaneous Radio-Frequency Ablation (RFA) Is Affected by Complete Radiological Response

    PubMed Central

    Cabibbo, Giuseppe; Maida, Marcello; Genco, Chiara; Alessi, Nicola; Peralta, Marco; Butera, Giuseppe; Galia, Massimo; Brancatelli, Giuseppe; Genova, Claudio; Raineri, Maurizio; Orlando, Emanuele; Attardo, Simona; Giarratano, Antonino; Midiri, Massimo; Di Marco, Vito; Craxì, Antonio; Cammà, Calogero

    2013-01-01

    Background Radio-frequency ablation (RFA) has been employed in the treatment of Barcelona Clinic Liver Cancer (BCLC) early stage hepatocellular carcinoma (HCC) as curative treatments. Aim To assess the effectiveness and the safety of RFA in patients with early HCC and compensated cirrhosis. Methods A cohort of 151 consecutive patients with early stage HCC (122 Child-Pugh class A and 29 class B patients) treated with RFA were enrolled. Clinical, laboratory and radiological follow-up data were collected from the time of first RFA. A single lesion was observed in 113/151 (74.8%), two lesions in 32/151 (21.2%), and three lesions in 6/151 (4%) of patients. Results The overall survival rates were 94%, 80%, 64%, 49%, and 41% at 12, 24, 36, 48 and 60 months, respectively. Complete response (CR) at 1 month (p<0.0001) and serum albumin levels (p = 0.0004) were the only variables indipendently linked to survival by multivariate Cox model. By multivariate analysis, tumor size (p = 0.01) is the only variable associated with an increased likehood of CR. The proportion of major complications after treatment was 4%. Conclusions RFA is safe and effective for managing HCC with cirrhosis, especially for patients with HCC ≤3 cm and higher baseline albumin levels. Complete response after RFA significantly increases survival. PMID:23922893

  2. Radiofrequency thermal ablation of breast tumors combined with intralesional administration of IL-7 and IL-15 augments anti-tumor immune responses and inhibits tumor development and metastasis

    PubMed Central

    Habibi, Mehran; Kmieciak, Maciej; Graham, Laura; Morales, Johanna K; Bear, Harry D; Manjili, Masoud H

    2008-01-01

    Tumor development or recurrence is always a matter of concern following radiofrequency thermal ablation (RFA) of tumors. To determine whether combining RFA with immunologically active cytokines might induce tumor-specific immune responses against mammary carcinoma and inhibit tumor development or metastasis, we evaluated intralesional injection of IL-7 and IL-15 in RFA-treated murine tumors. We used two different breast carcinoma models: neu-overexpressing mouse mammary carcinoma (MMC) in FVBN202 transgenic mouse and 4T1 tumors in Balb/c mouse. MMC tend to relapse even in the presence of neu-specific immune responses, and 4T1 is a weakly immunogenic, aggressive and highly metastatic transplantable tumor. In vivo growth of both of these tumors is also associated with increased numbers of CD11b+Gr1+ myeloid-derived suppressor cells (MDSC). We showed for the first time that unlike RFA alone, RFA combined with the administration of intralesional IL-7 and IL-15 (after RFA), induced immune responses to tumors, inhibited tumor development and lung metastasis, and reduced MDSC. PMID:18425677

  3. Radiofrequency ablation combined with liposomal quercetin to increase tumour destruction by modulation of heat shock protein production in a small animal model

    PubMed Central

    Yang, Wei; Ahmed, Muneeb; Tasawwar, Beenish; Levchenko, Tatyana; Sawant, Rupa R.; Collins, Michael; Signoretti, Sabina; Torchilin, Vladimir; Goldberg, S. Nahum

    2012-01-01

    Purpose To investigate the effect of heat shock protein (HSP) modulation on tumour coagulation by combining radiofrequency (RF) ablation with adjuvant liposomal quercetin and/or doxorubicin in a rat tumour model. Methods Sixty R3230 breast adenocarcinoma tumours/animals were used in this IACUC-approved study. Initially, 60 tumours (n = 6, each subgroup) were randomised into five groups: (1) RF alone, (2) intravenous (IV) liposomal quercetin alone (1 mg/kg), (3) IV liposomal quercetin followed 24 h later with RF, (4) RF followed 15 min later by IV liposomal doxorubicin (8 mg/kg), (5) IV liposomal quercetin 24 h before RF followed by IV liposomal doxorubicin 15 min post-ablation. Animals were sacrificed 4 or 24 h post-treatment and gross coagulation diameters were compared. Next, immunohistochemistry staining was performed for Hsp70 and cleaved caspase-3 expression. Comparisons were performed by using Student t-tests or ANOVA. Results Combination RF-quercetin significantly increased coagulation size compared with either RF or liposomal quercetin alone (13.1 ± 0.7 mm vs. 8.8 ± 1.2 mm or 2.3 ± 1.3 mm, respectively, P < 0.001 for all comparisons). Triple therapy (quercetin-RF-doxorubicin) showed larger coagulation diameter (14.5 ± 1.0mm) at 24 h than quercetin-RF (P = 0.016) or RF-doxorubicin (13.2 ± 1.3 mm, P = 0.042). Combination quercetin-RF decreased Hsp70 expression compared with RF alone at both 4 h (percentage of stained cells/hpf 22.4 ± 13.9% vs. 38.8 ± 16.1%, P < 0.03) and 24 h (45.2 ± 10.5% vs. 81.1 ± 3.6%, P < 0.001). Quercetin-RF increased cleaved caspase-3 expression at both 4 h (percentage of stained cells/hpf 50.7 ± 13.4% vs. 41.9 ± 15.1%, P < 0.03) and 24 h (37.4 ± 7.8% vs. 33.2 ± 6.5%, P = 0.045); with, triple therapy (quercetin-RF-doxorubicin) resulting in the highest levels of apoptosis (45.1 ± 10.7%) at 24 h. Similar trends were observed for rim thickness. Conclusions Suppression of HSP production using adjuvant liposomal quercetin can

  4. Ablative therapies for renal tumors

    PubMed Central

    Ramanathan, Rajan; Leveillee, Raymond J.

    2010-01-01

    Owing to an increased use of diagnostic imaging for evaluating patients with other abdominal conditions, incidentally discovered kidney masses now account for a majority of renal tumors. Renal ablative therapy is assuming a more important role in patients with borderline renal impairment. Renal ablation uses heat or cold to bring about cell death. Radiofrequency ablation and cryoablation are two such procedures, and 5-year results are now emerging from both modalities. Renal biopsy at the time of ablation is extremely important in order to establish tissue diagnosis. Real-time temperature monitoring at the time of radiofrequency ablation is very useful to ensure adequacy of ablation. PMID:21789083

  5. Renal Artery Embolization Combined With Radiofrequency Ablation in a Porcine Kidney Model: Effect of Small and Narrowly Calibrated Microparticles as Embolization Material on Coagulation Diameter, Volume, and Shape

    SciTech Connect

    Sommer, C. M. Kortes, N.; Zelzer, S.; Arnegger, F. U.; Stampfl, U.; Bellemann, N.; Gehrig, T.; Nickel, F.; Kenngott, H. G.; Mogler, C.; Longerich, T.; Meinzer, H. P.; Richter, G. M.; Kauczor, H. U.; Radeleff, B. A.

    2011-02-15

    The purpose of this study was to evaluate the effect of renal artery embolization with small and narrowly calibrated microparticles on the coagulation diameter, volume, and shape of radiofrequency ablations (RFAs) in porcine kidneys. Forty-eight RFAs were performed in 24 kidneys of 12 pigs. In 6 animals, bilateral renal artery embolization was performed with small and narrowly calibrated microparticles. Upper and lower kidney poles were ablated with identical system parameters. Applying three-dimensional segmentation software, RFAs were segmented on registered 2 mm-thin macroscopic slices. Length, depth, width, volume{sub s}egmented, and volume{sub c}alculated were determined to describe the size of the RFAs. To evaluate the shape of the RFAs, depth-to-width ratio (perfect symmetry-to-lesion length was indicated by a ratio of 1), sphericity ratio (perfect sphere was indicated by a sphericity ratio of 1), eccentricity (perfect sphere was indicated by an eccentricity of 0), and circularity (perfect circle was indicated by a circularity of 1) were determined. Embolized compared with nonembolized RFAs showed significantly greater depth (23.4 {+-} 3.6 vs. 17.2 {+-} 1.8 mm; p < 0.001) and width (20.1 {+-} 2.9 vs. 12.6 {+-} 3.7 mm; p < 0.001); significantly larger volume{sub s}egmented (8.6 {+-} 3.2 vs. 3.0 {+-} 0.7 ml; p < 0.001) and volume{sub c}alculated (8.4 {+-} 3.0 ml vs. 3.3 {+-} 1.1 ml; p < 0.001); significantly lower depth-to-width (1.17 {+-} 0.10 vs. 1.48 {+-} 0.44; p < 0.05), sphericity (1.55 {+-} 0.44 vs. 1.96 {+-} 0.43; p < 0.01), and eccentricity (0.84 {+-} 0.61 vs. 1.73 {+-} 0.91; p < 0.01) ratios; and significantly greater circularity (0.62 {+-} 0.14 vs. 0.45 {+-} 0.16; p < 0.01). Renal artery embolization with small and narrowly calibrated microparticles affected the coagulation diameter, volume, and shape of RFAs in porcine kidneys. Embolized RFAs were significantly larger and more spherical compared with nonembolized RFAs.

  6. Comparison of Topical Anesthetics for Radiofrequency Ablation of Achrocordons: Eutectic Mixture of Lignocaine/Prilocaine versus Lidocaine/Tetracaine

    PubMed Central

    Mishra, Nitin; Chauhan, Sandhya; Rastogi, Madhur Kant

    2014-01-01

    Introduction. Topical application of local anesthetics is currently considered to be the easiest, most effective, and convenient way for treatment of patients who may be undergoing superficial dermatosurgical procedures. Materials and Methods. This study compares the anesthetic potential of 2.5% lidocaine and 2.5% prilocaine topical cream with 7% lignocaine and 7% tetracaine combination cream for radio ablative dermatosurgery when applied, under occlusion, for 30 minutes. 40 subjects of achrocordons were enrolled in this split-side randomized trial. Result. The pain severity experienced by subjects in terms of visual analogue scale score was significantly lesser for lignocaine/tetracaine combination cream as compared to lidocaine/prilocaine combination. Conclusion. This small study proves the efficacy of lidocaine/tetracaine combination as a topical anesthetic cream when applied for a short time interval of 30 minutes. This will help a dermatosurgeon to perform various dermatological procedures in a better and efficient manner with a shorter waiting period for analgesia to set in. PMID:24600520

  7. Effects of Lugol staining on stenosis formation induced by radiofrequency ablation of esophageal squamous epithelium: a study in a porcine model.

    PubMed

    Schölvinck, D W; Alvarez Herrero, L; Visser, M; Bergman, J J G H M; Weusten, B L A M

    2015-10-01

    Preliminary data show higher stricture rates after radiofrequency ablation (RFA) for early esophageal squamous neoplasia compared with Barrett's esophagus. We studied the effects of Lugol stain (LS) directly prior to RFA on stricture formation in squamous epithelium. Of 16 pigs, the distal half of the esophagus was LS, followed by circumferential RFA (single application 12 J/cm(2) ) in the unstained and stained esophagus. Pigs were euthanized at day 0 (n = 4), 3 (n = 4), or 28 (n = 8). Histology was evaluated in four areas: blank-control (no RFA, no LS), blank-RFA (no LS), LS+RFA, and LS-control (no RFA). Stenosis severity in LS+RFA and blank-RFA at 28 days was assessed by the ratio of the mucosal diameter at the RFA area to the diameter 2 cm proximal of this zone. Histology showed submucosal edema in 50% of LS+RFA versus 0% in blank-RFA. Severity and depth of inflammation (day 3) was equal in LS+RFA and blank-RFA. Severity and depth of fibrosis (day 28) appeared more severe in LS+RFA. Consequently, stenosis was present in 100% (LS+RFA) versus 12.5% (blank-RFA). The stenosis-severity ratio was 0.40 (interquartile range 0.29-0.45) in LS+RFA versus 0.73 (interquartile range 0.64-0.78) in blank-RFA (P = 0.012). Limitations of this study were the difference in uptake of LS between pigs and humans, the difference in esophageal anatomy between pigs and humans, and between the proximal and distal esophagus within pigs. In conclusion, in the porcine squamous esophagus, stenosis rate and severity after RFA increased when preceded by LS. LS may be contributing in the altered response of squamous epithelium to RFA as compared with Barrett's esophagus.

  8. Atrial rhythm influences catheter tissue contact during radiofrequency catheter ablation of atrial fibrillation: comparison of contact force between sinus rhythm and atrial fibrillation.

    PubMed

    Matsuda, Hisao; Parwani, Abdul Shokor; Attanasio, Philipp; Huemer, Martin; Wutzler, Alexander; Blaschke, Florian; Haverkamp, Wilhelm; Boldt, Leif-Hendrik

    2016-09-01

    Catheter tissue contact force (CF) is an important factor for durable lesion formation during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Since CF varies in the beating heart, atrial rhythm during RFCA may influence CF. A high-density map and RFCA points were obtained in 25 patients undergoing RFCA of AF using a CF-sensing catheter (Tacticath, St. Jude Medical). The operators were blinded to the CF information. Contact type was classified into three categories: constant, variable, and intermittent contact. Average CF and contact type were analyzed according to atrial rhythm (SR vs. AF) and anatomical location. A total of 1364 points (891 points during SR and 473 points during AF) were analyzed. Average CFs showed no significant difference between SR (17.2 ± 11.3 g) and AF (17.2 ± 13.3 g; p = 0.99). The distribution of points with an average CF of ≥20 and <10 g also showed no significant difference. However, the distribution of excessive CF (CF ≥40 g) was significantly higher during AF (7.4 %) in comparison with SR (4.2 %; p < 0.05). At the anterior area of the right inferior pulmonary vein (RIPV), the average CF during AF was significantly higher than during SR (p < 0.05). Constant contact was significantly higher during AF (32.2 %) when compared to SR (9.9 %; p < 0.01). Although the average CF was not different between atrial rhythms, constant contact was more often achievable during AF than it was during SR. However, excessive CF also seems to occur more frequently during AF especially at the anterior part of RIPV.

  9. [Predictors of Efficacy of Radiofrequency Ablation of Pulmonary Veins Performed During Coronary Bypass Surgery in Patients With Ischemic Heart Disease and Paroxysmal Atrial Fibrillation].

    PubMed

    Iskenderov, B G; Rakhmatullov, A F

    2015-01-01

    We performed simultaneous coronary artery bypass grafting (CABG) and radiofrequency ablation (RFA) ostia of pulmonary veins in 254 patients (147 men and 107 women) with ischemic heart disease and paroxysmal atrial fibrillation (AF). In-hospital mortality in patients with early recurrence of AF was 8.4%, in patients without recurrence of AF 1.9% (χ2 = 4.65; p = 0.03). The patients were followed-up during 12 months after operation. During follow-up 166 patients (69.5%) had no recurrence of AF without receiving antiarrhythmic drugs (AAP), 33 patients (13.8%) had recurrences of AF, and 40 patients (16.7%) receiving AAD had repeated rare paroxysms of AF. Main predictors of late AF recurrence were age > 65 years, AF duration > 5 years, preoperative atrial effective refractory period < 240 ms, frequency threshold of AF induction < 400 counts/min, anteroposterior left atrial size > 50 mm, glomerular filtration rate < 60 ml/min/1.73 m2. Reverse dynamics of structural, functional and electrophysiological parameters of the heart due to CABG and RFA, use of β-blockers, angiotensin converting enzyme inhibitors and aldosterone antagonists were associated with the preservation of a stable sinus rhythm. The cardiovascular mortality during 12 months follow-up accounted for 2.1% and 1.2% in groups of patients with and without late recurrences of AF respectively (p > 0.05) to coronary artery bypass grafting surgery and RFA, taking drugs--β-blockers, angiotensin converting enzyme inhibitors and aldosterone antagonists--were associated with the preservation of a stable sinus rhythm.

  10. Treatment of Chronic Plantar Heel Pain With Radiofrequency Neural Ablation of the First Branch of the Lateral Plantar Nerve and Medial Calcaneal Nerve Branches.

    PubMed

    Arslan, Aydın; Koca, Tuba Tulay; Utkan, Ali; Sevimli, Resit; Akel, İbrahim

    2016-01-01

    From March 2012 to February 2013, 37 patients experiencing plantar heel pain for ≥6 months despite treatment with physical therapy and other conservative treatment modalities were followed up. If neurogenic heel pain originating from the first branch of the lateral plantar nerve was present, with or without the medial calcaneal nerve, diagnostic nerve blocks to these nerves were performed for confirmation. If the pain was determined to be of neurogenic origin, radiofrequency neural ablation (RFNA) was applied to the corresponding sensory nerve endings. Pain was evaluated using the visual analog scale, and patients were followed for at least one year. A total of 41 feet from 37 patients (30 [81.1%] females, 7 [18.9%] males; mean age, 50.7 ± 1.6 years; mean body mass index, 30.6 ± 0.7 kg/m(2)) were included. The mean visual analog scale scores improved significantly from 1 to 6 to 12 months after the procedure relative to before the procedure, with 88% of all patients rating the treatment as either very successful or successful at 12 months postoperatively. RFNA applied to both the first branch of the lateral plantar nerve and the medial calcaneal nerve sensory branches (16 [39%] feet) and only the first branch of the lateral plantar nerve sensory branches (25 [61%] feet) showed similarly high levels of success. Of the 41 feet, 28 [68.3%] had received extracorporeal shockwave therapy, 35 [85.4%] had received steroid injections, and 22 [53.7%] had received both extracorporeal shockwave therapy and steroid injections before RFNA as an index procedure. All were unresponsive to these previous treatments. In contrast, almost all (88%) were treated successfully with RFNA. Despite a high incidence of neurologic variations, with a precise diagnosis and good application of the technique using the painful points, chronic plantar heel pain can be treated successfully with RFNA.

  11. Atrial rhythm influences catheter tissue contact during radiofrequency catheter ablation of atrial fibrillation: comparison of contact force between sinus rhythm and atrial fibrillation.

    PubMed

    Matsuda, Hisao; Parwani, Abdul Shokor; Attanasio, Philipp; Huemer, Martin; Wutzler, Alexander; Blaschke, Florian; Haverkamp, Wilhelm; Boldt, Leif-Hendrik

    2016-09-01

    Catheter tissue contact force (CF) is an important factor for durable lesion formation during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Since CF varies in the beating heart, atrial rhythm during RFCA may influence CF. A high-density map and RFCA points were obtained in 25 patients undergoing RFCA of AF using a CF-sensing catheter (Tacticath, St. Jude Medical). The operators were blinded to the CF information. Contact type was classified into three categories: constant, variable, and intermittent contact. Average CF and contact type were analyzed according to atrial rhythm (SR vs. AF) and anatomical location. A total of 1364 points (891 points during SR and 473 points during AF) were analyzed. Average CFs showed no significant difference between SR (17.2 ± 11.3 g) and AF (17.2 ± 13.3 g; p = 0.99). The distribution of points with an average CF of ≥20 and <10 g also showed no significant difference. However, the distribution of excessive CF (CF ≥40 g) was significantly higher during AF (7.4 %) in comparison with SR (4.2 %; p < 0.05). At the anterior area of the right inferior pulmonary vein (RIPV), the average CF during AF was significantly higher than during SR (p < 0.05). Constant contact was significantly higher during AF (32.2 %) when compared to SR (9.9 %; p < 0.01). Although the average CF was not different between atrial rhythms, constant contact was more often achievable during AF than it was during SR. However, excessive CF also seems to occur more frequently during AF especially at the anterior part of RIPV. PMID:26498938

  12. Transcatheter arterial embolization combined with radiofrequency ablation activates CD8+ T-cell infiltration surrounding residual tumors in the rabbit VX2 liver tumors

    PubMed Central

    Duan, Xu-Hua; Li, Teng-Fei; Zhou, Guo-Feng; Han, Xin-Wei; Zheng, Chuan-Sheng; Chen, Peng-fei; Feng, Gan-Sheng

    2016-01-01

    Purpose To evaluate the effect of transcatheter arterial embolization (TAE) combined with radiofrequency ablation (RFA) treatment (TAE + RFA) on the expression of heat shock protein 70 (HSP70) in residual tumors and explore the relationship between the HSP70 and CD8+ T-cell infiltrate surrounding residual tumors in the rabbit VX2 liver tumor model. Materials and methods Animals with VX2 liver tumors were randomized into four groups (control, TAE, RFA, and TAE + RFA) with 15 rabbits in each group. Five rabbits in each group were sacrificed on days 1, 3, and 7 after treatment. HSP70 expression and infiltration of CD8+ T-cells in the liver and residual tumors surrounding the necrosis zone were detected by immunohistochemistry staining. The maximal diameters of tumor necrosis, numbers of metastases, and tumor growth rate were compared on day 7 after treatment. Results TAE + RFA achieved larger maximal diameter of tumor necrosis, lower tumor growth rate, and fewer metastatic lesions, compared with other treatments on day 7. The number of CD8+ T-cells in the TAE + RFA group was significantly higher than in other groups on days 1, 3, and 7. There was a positive correlation between HSP70 expression level and infiltration of CD8+ T-cells surrounding the residual tumor on day 1 (r=0.9782, P=0.012), day 3 (r=0.93, P=0.021), and day 7 (r=0.8934, P=0.034). Conclusion In the rabbit VX2 liver tumor model, TAE + RFA activated the highest number of CD8+ T-cells surrounding residual tumors. TAE + RFA appears to be a beneficial therapeutic modality for tumor control and antitumor immune response in this model. PMID:27274279

  13. Treatment of Chronic Plantar Heel Pain With Radiofrequency Neural Ablation of the First Branch of the Lateral Plantar Nerve and Medial Calcaneal Nerve Branches.

    PubMed

    Arslan, Aydın; Koca, Tuba Tulay; Utkan, Ali; Sevimli, Resit; Akel, İbrahim

    2016-01-01

    From March 2012 to February 2013, 37 patients experiencing plantar heel pain for ≥6 months despite treatment with physical therapy and other conservative treatment modalities were followed up. If neurogenic heel pain originating from the first branch of the lateral plantar nerve was present, with or without the medial calcaneal nerve, diagnostic nerve blocks to these nerves were performed for confirmation. If the pain was determined to be of neurogenic origin, radiofrequency neural ablation (RFNA) was applied to the corresponding sensory nerve endings. Pain was evaluated using the visual analog scale, and patients were followed for at least one year. A total of 41 feet from 37 patients (30 [81.1%] females, 7 [18.9%] males; mean age, 50.7 ± 1.6 years; mean body mass index, 30.6 ± 0.7 kg/m(2)) were included. The mean visual analog scale scores improved significantly from 1 to 6 to 12 months after the procedure relative to before the procedure, with 88% of all patients rating the treatment as either very successful or successful at 12 months postoperatively. RFNA applied to both the first branch of the lateral plantar nerve and the medial calcaneal nerve sensory branches (16 [39%] feet) and only the first branch of the lateral plantar nerve sensory branches (25 [61%] feet) showed similarly high levels of success. Of the 41 feet, 28 [68.3%] had received extracorporeal shockwave therapy, 35 [85.4%] had received steroid injections, and 22 [53.7%] had received both extracorporeal shockwave therapy and steroid injections before RFNA as an index procedure. All were unresponsive to these previous treatments. In contrast, almost all (88%) were treated successfully with RFNA. Despite a high incidence of neurologic variations, with a precise diagnosis and good application of the technique using the painful points, chronic plantar heel pain can be treated successfully with RFNA. PMID:27073185

  14. Determinants of Local Progression After Computed Tomography-Guided Percutaneous Radiofrequency Ablation for Unresectable Lung Tumors: 9-Year Experience in a Single Institution

    SciTech Connect

    Okuma, Tomohisa Matsuoka, Toshiyuki; Yamamoto, Akira; Oyama, Yoshimasa; Hamamoto, Shinichi; Toyoshima, Masami; Nakamura, Kenji; Miki, Yukio

    2010-08-15

    The purpose of this study was to retrospectively determine the local control rate and contributing factors to local progression after computed tomography (CT)-guided radiofrequency ablation (RFA) for unresectable lung tumor. This study included 138 lung tumors in 72 patients (56 men and 16 women; age 70.0 {+-} 11.6 years (range 31-94); mean tumor size 2.1 {+-} 1.2 cm [range 0.2-9]) who underwent lung RFA between June 2000 and May 2009. Mean follow-up periods for patients and tumors were 14 and 12 months, respectively. The local progression-free rate and survival rate were calculated to determine the contributing factors to local progression. During follow-up, 44 of 138 (32%) lung tumors showed local progression. The 1-, 2-, 3-, and 5-year overall local control rates were 61, 57, 57, and 38%, respectively. The risk factors for local progression were age ({>=}70 years), tumor size ({>=}2 cm), sex (male), and no achievement of roll-off during RFA (P < 0.05). Multivariate analysis identified tumor size {>=}2 cm as the only independent factor for local progression (P = 0.003). For tumors <2 cm, 17 of 68 (25%) showed local progression, and the 1-, 2-, and 3-year overall local control rates were 77, 73, and 73%, respectively. Multivariate analysis identified that age {>=}70 years was an independent determinant of local progression for tumors <2 cm in diameter (P = 0.011). The present study sh