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Sample records for wet radiofrequency ablation

  1. Radiofrequency ablation in dermatology

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    Sachdeva Silonie

    2007-01-01

    Full Text Available Radiofreqeuency ablation is a versatile dermatosurgical procedure used for surgical management of skin lesions by using various forms of alternating current at an ultra high frequency. The major modalities in radiofrequency are electrosection, electrocoagulation, electrodessication and fulguration. The use of radiofrequency ablation in dermatosurgical practice has gained importance in recent years as it can be used to treat most of the skin lesions with ease in less time with clean surgical field due to adequate hemostasis and with minimal side effects and complications. This article focuses on the major tissue effects and factors influencing radiofrequency ablation and its application for various dermatological conditions.

  2. Radiofrequency ablation of osteoid osteoma

    NARCIS (Netherlands)

    Vanderschueren, Geert Maria Joris Michael

    2009-01-01

    The main purpose of this thesis was to evaluate the effectiveness and safety of CT-guided radiofrequency ablation for the treatment of spinal and non-spinal osteoid osteomas. Furthermore, the technical requirements needed for safe radiofrequency ablation and the clinical outcome after radiofrequency

  3. Computational modelling of internally cooled wet (ICW) electrodes for radiofrequency ablation: impact of rehydration, thermal convection and electrical conductivity.

    Science.gov (United States)

    Trujillo, Macarena; Bon, Jose; Berjano, Enrique

    2017-09-01

    (1) To analyse rehydration, thermal convection and increased electrical conductivity as the three phenomena which distinguish the performance of internally cooled electrodes (IC) and internally cooled wet (ICW) electrodes during radiofrequency ablation (RFA), (2) Implement a RFA computer model with an ICW which includes these phenomena and (3) Assess their relative influence on the thermal and electrical tissue response and on the coagulation zone size. A 12-min RFA in liver was modelled using an ICW electrode (17 G, 3 cm tip) by an impedance-control pulsing protocol with a constant current of 1.5 A. A model of an IC electrode was used to compare the ICW electrode performance and the computational results with the experimental results. Rehydration and increased electrical conductivity were responsible for an increase in coagulation zone size and a delay (or absence) in the occurrence of abrupt increases in electrical impedance (roll-off). While the increased electrical conductivity had a remarkable effect on enlarging the coagulation zone (an increase of 0.74 cm for differences in electrical conductivity of 0.31 S/m), rehydration considerably affected the delay in roll-off, which, in fact, was absent with a sufficiently high rehydration level. In contrast, thermal convection had an insignificant effect for the flow rates considered (0.05 and 1 mL/min). Computer results suggest that rehydration and increased electrical conductivity were mainly responsible for the absence of roll-off and increased size of the coagulation zone, respectively, and in combination allow the thermal and electrical performance of ICW electrodes to be modelled during RFA.

  4. Musculoskeletal interventional radiology: radiofrequency ablation.

    Science.gov (United States)

    Ward, Emily; Munk, Peter L; Rashid, Faisal; Torreggiani, William C

    2008-05-01

    Radiofrequency ablation is the use of low-voltage high-frequency electrical energy to heat and destroy abnormal tissues within the human body. It has gained increasing acceptance as both a primary and secondary form of treatment in the musculoskeletal system because of its excellent safety profile, ease of use, and technical success. In the musculoskeletal system, radiofrequency ablation may be used to treat a wide range of lesions that include primary lesions such as osteoid osteomas and a variety of metastases both within the osseous skeleton as well as those lying within the muscles and soft tissues. In this chapter, a background to the principles, physics, and indications of radiofrequency is presented as well as an in-depth description of radiofrequency ablation techniques that may be utilized in the musculoskeletal system.

  5. Radiofrequency Catheter Ablation of Parahisian Accessory Pathway

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    Korodi Szilamér

    2016-06-01

    Full Text Available Radiofrequency catheter ablation of parahisian accessory pathways in pre-excitation syndrome is a challenging task, due to the extremely high risk of complete atrioventricular block. In this brief report we describe the case of a 32 year-old man presenting a parahisian accessory pathway, who has been successfully treated by radiofrequency ablation. Radiofrequency catheter ablation using low-power radiofrequency current is considered to be the most appropiate method of ablation in adult patients.

  6. Radiofrequency ablation of pulmonary tumors

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    Crocetti, Laura, E-mail: l.crocetti@med.unipi.i [Division of Diagnostic Imaging and Intervention, Department of Liver Transplants, Hepatology and Infectious Diseases, Pisa University School of Medicine (Italy); Lencioni, Riccardo [Division of Diagnostic Imaging and Intervention, Department of Liver Transplants, Hepatology and Infectious Diseases, Pisa University School of Medicine (Italy)

    2010-07-15

    The development of image-guided percutaneous techniques for local tumor ablation has been one of the major advances in the treatment of solid tumors. Among these methods, radiofrequency (RF) ablation is currently established as the primary ablative modality at most institutions. RF ablation is accepted as the best therapeutic choice for patients with early-stage hepatocellular carcinoma when liver transplantation or surgical resection are not suitable options and is considered as a viable alternate to surgery for inoperable patients with limited hepatic metastatic disease, especially from colorectal cancer. Recently, RF ablation has been demonstrated to be a safe and valuable treatment option for patients with unresectable or medically inoperable lung malignancies. Resection should remain the standard therapy for non-small cell lung cancer (NSCLC) but RF ablation may be better than conventional external-beam radiation for the treatment of the high-risk individual with NSCLC. Initial favourable outcomes encourage combining radiotherapy and RF ablation, especially for treating larger tumors. In the setting of colorectal cancer lung metastases, survival rates provided by RF ablation in selected patients, are substantially higher than those obtained with any chemotherapy regimens and provide indirect evidence that RF ablation therapy improves survival in patients with limited lung metastatic disease.

  7. Lymphangioma circumscriptum treated with radiofrequency ablation

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    Silonie Sachdeva

    2011-01-01

    Full Text Available Lymphangioma circumscriptum (LC, a hamartomatous lymphatic malformation, is a therapeutic challenge for the dermatologist. Various modalities like surgical excision, lasers, and sclerotherapy have been used in the past to treat this notorious skin condition. We report the efficacy of a radiofrequency ablation in a patient with LC. The treatment efficacy of radiofrequency was satisfactory in our patient with no recurrence during 1 year follow-up period. The radiofrequency technique is a safe and economic treatment for management of LC.

  8. ROLE OF RADIOFREQUENCY ABLATION IN ADENOMA SEBACEUM

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    Ch. Madh

    2016-03-01

    Full Text Available Adenoma sebaceum, pathognomonic of tuberous sclerosis, are tiny angiofibromas which commonly occur over central part of face. Recurrence after treatment is common and hence a need for inexpensive, safe and efficient treatment is required. Radiofrequency ablation is a safe and an economical procedure and has been known to cause less scarring with good aesthetic results compared to other ablative methods such as electrocautery.

  9. Radiofrequency Ablation Complicated by Skin Burn

    Science.gov (United States)

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

    2011-01-01

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

  10. Cryoballoon ablation versus radiofrequency ablation for atrial fibrillation.

    Science.gov (United States)

    Reissmann, Bruno; Metzner, Andreas; Kuck, Karl-Heinz

    2017-05-01

    Catheter ablation (CA) provides the most effective treatment option for patients suffering from symptomatic atrial fibrillation (AF). The procedural cornerstone of all ablation strategies and for all entities of AF is the electrical isolation of the pulmonary veins (PV). CA with the use of radiofrequency (RF) in conjunction with a 3-dimensional electroanatomical mapping system is the most established ablation approach, but it demands a long learning curve and recurrences of AF are commonly the result of recovered PV conduction. As a consequence, novel ablation systems such as the Cryoballoon (CB) have been evolved aiming at facilitation and increased efficacy of pulmonary vein isolation (PVI). CB ablation is characterized by a short learning curve as well as short procedure times and demonstrated non-inferiority with regard to safety and efficacy when being directly compared to RF ablation for treatment of paroxysmal AF. However, RF ablation is first choice for treatment of persistent AF, in particular when expanded ablation strategies beyond PVI are intended in order to improve clinical outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Effective treatment of chronic radiation proctitis using radiofrequency ablation

    National Research Council Canada - National Science Library

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

    2009-01-01

    .... 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...

  12. CT-guided radiofrequency tumor ablation in children

    Energy Technology Data Exchange (ETDEWEB)

    Botsa, Evanthia [National and Kapodistrian University of Athens, First Pediatric Clinic, Agia Sofia Children' s Hospital, Athens (Greece); Poulou, Loukia S.; Koundouraki, Antonia; Thanos, Loukas [Sotiria General Hospital for Chest Diseases, Department of Medical Imaging and Interventional Radiology, Athens (Greece); Koutsogiannis, Ioannis [General Military Hospital NIMTS, Department of Medical Imaging, Athens (Greece); Ziakas, Panayiotis D. [Warren Alpert Medical School of Brown University Rhode Island Hospital, Division of Infectious Diseases, Providence, RI (United States); Alexopoulou, Efthimia [Attikon University Hospital, Second Department of Radiology, Athens University School of Medicine, Athens (Greece)

    2014-11-15

    Image-guided radiofrequency ablation is a well-accepted technique of interventional oncology in adults. To evaluate the efficacy and safety of CT-guided radiofrequency ablation as a minimally invasive treatment for metastatic neoplasms in children. A total of 15 radiofrequency ablation sessions were performed in 12 children and young adults (median age 9.5; range 5-18 years) with metastatic malignancies. Seven children and young adults had secondary hepatic lesions, three had pulmonary and two had bone lesions. Radiofrequency ablation was performed under conscious sedation. The median lesion size was 1.7 cm (range 1.3-2.8 cm). The median time for ablation was 8 min (range 7-10 min). Radiofrequency procedures were technically successful in all tumors. Postablation imaging immediately after, and 1 month and 3 months after radiofrequency ablation showed total necrosis in all patients. At 6-month follow-up, three patients (all with lesion size >2 cm) had local recurrence and underwent a second radiofrequency ablation session. At 2-year follow-up no patient had recurrence of the treated tumor. Post-ablation syndrome occurred in four children. No major complication occurred. CT-guided radiofrequency tumor ablation was safe and efficient for palliative treatment in our cohort of patients. (orig.)

  13. Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation

    DEFF Research Database (Denmark)

    Walfridsson, H; Walfridsson, U; Nielsen, J Cosedis

    2015-01-01

    AIMS: The Medical ANtiarrhythmic Treatment or Radiofrequency Ablation in Paroxysmal Atrial Fibrillation (MANTRA-PAF) trial assessed the long-term efficacy of an initial strategy of radiofrequency ablation (RFA) vs. antiarrhythmic drug therapy (AAD) as first-line treatment for patients with PAF...

  14. Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation

    DEFF Research Database (Denmark)

    Cosedis Nielsen, Jens; Johannessen, Arne; Raatikainen, Pekka

    2012-01-01

    There are limited data comparing radiofrequency catheter ablation with antiarrhythmic drug therapy as first-line treatment in patients with paroxysmal atrial fibrillation.......There are limited data comparing radiofrequency catheter ablation with antiarrhythmic drug therapy as first-line treatment in patients with paroxysmal atrial fibrillation....

  15. Photoacoustic characterization of radiofrequency ablation lesions

    Science.gov (United States)

    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.

  16. LAPAROSCOPIC NEPHRECTOMY USING RADIOFREQUENCY THERMAL ABLATION

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    B. Ya. Alekseev

    2012-01-01

    Full Text Available The wide use of current diagnostic techniques, such as ultrasound study, computed tomography, and magnetic resonance imaging, has led to significantly increased detection rates for disease in its early stages. This gave rise to a change in the standards for the treatment of locally advanced renal cell carcinoma (RCC. Laparoscopic nephrectomy (LN has recently become the standard treatment of locally advanced RCC in the clinics having much experience with laparoscopic surgery. The chief drawback of LN is difficulties in maintaining intraoperative hemostasis and a need for creating renal tissue ischemia. The paper gives the intermediate results of application of the new procedure of LN using radiofrequency thermal ablation in patients with non-ischemic early-stage RCC.

  17. Current situation on radiofrequency ablation of hepatic hemangioma

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    Zou, Hua

    2013-01-01

    The recent progress in radiofrequency ablation (RFA) of hepatic hemangioma was reviewed, with a focus on radiofrequency electrodes, treatment modalities, complications, and prevention strategies. The foundation for the standardization of RFA of hepatic hemangioma was laid. The standardization of RFA will help to promote its clinical application and development as an important minimally invasive technique for hepatic hemangioma.

  18. Current situation on radiofrequency ablation of hepatic hemangioma

    Directory of Open Access Journals (Sweden)

    ZOU Hua

    2013-08-01

    Full Text Available The recent progress in radiofrequency ablation (RFA of hepatic hemangioma was reviewed, with a focus on radiofrequency electrodes, treatment modalities, complications, and prevention strategies. The foundation for the standardization of RFA of hepatic hemangioma was laid. The standardization of RFA will help to promote its clinical application and development as an important minimally invasive technique for hepatic hemangioma.

  19. Endometrial ablation

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

  20. Effects of heating with radiofrequency power on myocardial impulse conduction: is radiofrequency ablation exclusively thermally mediated?

    NARCIS (Netherlands)

    Simmers, T. A.; de Bakker, J. M.; Wittkampf, F. H.; Hauer, R. N.

    1996-01-01

    Although it is generally accepted that radiofrequency (RF) ablation causes exclusively thermally mediated effects, it has never been proved. In a previous report, temperatures required to induce conduction block in superfused canine epicardial ventricular myocardium were identified by exposure to

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

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    Cuneyt Kucur

    2015-01-01

    Full Text Available 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.

  2. Endoscopic ultrasound-guided radiofrequency ablation of the pancreas

    DEFF Research Database (Denmark)

    Silviu, Ungureanu Bogdan; Daniel, Pirici; Claudiu, Mărgăritescu

    2015-01-01

    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...... 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...

  3. Rapid growth of left atrial myxoma after radiofrequency ablation.

    Science.gov (United States)

    Rubio Alvarez, José; Martinez de Alegria, Anxo; Sierra Quiroga, Juan; Adrio Nazar, Belen; Rubio Taboada, Carola; Martinez Comendador, José Manuel

    2013-01-01

    Atrial myxoma is the most common benign tumor of the heart, but its appearance after radiofrequency ablation is very rare. We report a case in which an asymptomatic, rapidly growing cardiac myxoma arose in the left atrium after radiofrequency ablation. Two months after the procedure, cardiovascular magnetic resonance, performed to evaluate the right ventricular anatomy, revealed a 10 × 10-mm mass (assumed to be a thrombus) attached to the patient's left atrial septum. Three months later, transthoracic echocardiography revealed a larger mass, and the patient was diagnosed with myxoma. Two days later, a 20 × 20-mm myxoma weighing 37 g was excised. To our knowledge, the appearance of an atrial myxoma after radiofrequency ablation has been reported only once before. Whether tumor development is related to such ablation or is merely a coincidence is uncertain, but myxomas have developed after other instances of cardiac trauma.

  4. Radiofrequency ablation of the lateral palatal space for snoring

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    B. Tucker Woodson

    2017-06-01

    Full Text Available Objective: Pilot study to examine the effect of radiofrequency ablation (RFA of the lateral palatal fat pad in patients with socially-disruptive snoring. Method: Snoring outcomes and complications were compared between a group of patients with treated with RFA ablation of the lateral soft palate fat pad with or without inferior turbinate reduction (8 patients and another group undergoing inferior turbinate reduction alone (12 patients. Results: Snoring loudness and bothersomeness improved in the palate but not inferior turbinate group. Pain was mild and no major complications were observed. Conclusion: The study supports RFA ablation of the lateral palatal space as a potential low morbidity procedure for snoring. Keywords: Snoring, Radiofrequency, Somnoplasty, Radiofrequency ablation, Inferior turbinate reduction, Turbinoplasty

  5. Percutaneous extrapulmonary radiofrequency ablation for tumors in the hepatic dome.

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    Wang, Zhen-Yuan; Sun, Wen-Bing; Li, Ming-Ying; Zhang, Xiao-Xia; Ding, Xue-Mei

    2008-01-01

    This study aims to assess the feasibility of one lung ventilation and computed tomography-guided extrapulmonary percutaneous radiofrequency ablation for tumors in the hepatic dome. Eleven patients (10 men, 1 women; age range, 34-84 years) with 12 tumors in the hepatic dome were enrolled in the study after institutional review board approval and informed consent had been obtained. A 35F or 37F left-sided double-lumen endotracheal tube was intubated after general anesthesia was induced. The right lung is permitted to collapse, with selective left lungs ventilation. With CT monitoring, the RF electrode was inserted through the empty pleural space to the targeted tumor and radiofrequency ablation procedures were performed. The median operative time was 122 minutes. The median one lung ventilation time was 134 minutes. The procedures of one lung ventilation and percutaneous radiofrequency ablation were successfully performed. There was no bronchial intubation, one lung ventilation and percutaneous radiofrequency ablation related complications, excluding minor pleural effusions recovering without thoracentesis in 2 patients. Complete tumor necrosis was achieved in 10 patients (90.9%). One lung ventilation and computed tomography guided percutaneous extrapulmonary radiofrequency ablation for tumors in the hepatic dome appears to be useful and safe.

  6. Radiofrequency catheter ablation maintains its efficacy better than antiarrhythmic medication in patients with paroxysmal atrial fibrillation

    DEFF Research Database (Denmark)

    Raatikainen, M J Pekka; Hakalahti, Antti; Uusimaa, Paavo

    2015-01-01

    BACKGROUND: The Medical ANtiarrhythmic Treatment or Radiofrequency Ablation in Paroxysmal Atrial Fibrillation (MANTRA-PAF) is a randomized trial comparing radiofrequency catheter ablation (RFA) to antiarrhythmic drugs (AADs) as first-line treatment of paroxysmal atrial fibrillation (PAF). In order...

  7. Percutaneous radiofrequency ablation in painful bone metastases

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    German Garabano

    2015-09-01

    Full Text Available Backgraund There are different treatment for painful bone metastases (mtts, with different results. CT-guided Percutaneous Radiofrequency Ablation (CT-PRA is one of them. The pupose of this retrospective study was to assess the initial results using this methods, focusing on pain relief, showing details of the surgical technique. Methods 18 patients with an average age of 59.2 years and 15 months follow-up were treated. Nine mtts were located in the femur, 4 dorsal / lumbar spine, 3 in scapula and 2 in Iliac. The Mtts origin were Breast Ca 7 cases, lung in 4, Kidney in 4 and 3 in Thyroid. The rachis mtts were found at more than 10mm of the medullary cavity and mtts of long bones showed low risk of fracture. Lesions >3cm were treated whit CT-PRA  using Valleylab Rita needle and these <3cm with CoolTip needle. Pain was assessed by Visual Analog Scale (VAS preoperatively, at 2, 7 and 30 days, and then at 3 and 6 months. Results Preoperative pain score was 8.33 on average. At 7 days of ablatión de VAS score was 5 on average and at 30 days was 2 points. After at 3 and 6 months de VAS average was 1. This method had excellent patients tolerance and no complications. There were two recurrences which underwent endoprosthesis unconventional proximal femur and knee respectively, evolving favorably. Conclusion CT-guided APRF impresses a promising, simple and effective tool in the treatment of painfull bone mtts, achieving excellent pain control with good tolerance by the patient.

  8. Mechanisms for enlarging lesion size during irrigated tip radiofrequency ablation

    DEFF Research Database (Denmark)

    Petersen, Helen Høgh; Roman-Gonzalez, Javier; Johnson, Susan B

    2004-01-01

    INTRODUCTION: Irrigated tip radiofrequency ablation of cardiac arrhythmias was developed to increase the size of the radiofrequency-induced lesion, since cooling of the electrode tip allows use of higher power settings. The purpose of this study was to determine if the increased lesion size during...... and in vivo canine left ventricles were ablated. In vitro closed loop tip and showerhead irrigated tip catheters were compared. In vitro and in vivo showerhead tip catheters irrigated with solutions having different ionic content were compared. We found no difference in lesion size for closed loop...... and showerhead-type catheters (998 +/- 345 vs. 811 +/- 313 mm(3) during power-controlled ablation and 227 +/- 76 vs 318 +/- 127 mm(3) during temperature-controlled ablation). For irrigation with liquids having increasing ionic strength we found a decrease in lesion volume in vitro (361 +/- 249 vs. 812 +/- 229 mm...

  9. Radiofrequency ablation for the treatment of gastric antral vascular ectasia

    DEFF Research Database (Denmark)

    Dray, X.; Repici, A.; Gonzalez, P.

    2014-01-01

    Background and study aims: The traditional endoscopic treatment for gastric antral vascular ectasia (GAVE) is argon plasma coagulation, but results are not always positive. Radiofrequency ablation (RFA) is a new endoscopic therapy that may be an attractive option for the treatment of GAVE. The ai...

  10. Mitral valve perforation appearing years after radiofrequency ablation

    DEFF Research Database (Denmark)

    Fisch-Thomsen, Marie; Jensen, Jesper K; Egeblad, Henrik

    2011-01-01

    The case is reported of a young adult with Wolff-Parkinson-White (WPW) syndrome who, three years after a complicated radiofrequency (RF) catheter ablation procedure, developed dyspnea on exertion. Echocardiography revealed severe mitral valve regurgitation caused by a perforation of the posterior...

  11. Irrigated Tip Catheters for Radiofrequency Ablation in Ventricular Tachycardia

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    Andreas Müssigbrodt

    2015-01-01

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

  12. Complications associated with radiofrequency ablation of pulmonary veins.

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    Madrid Pérez, J M; García Barquín, P M; Villanueva Marcos, A J; García Bolao, J I; Bastarrika Alemañ, G

    Radiofrequency ablation is an efficacious alternative in patients with symptomatic atrial fibrillation who do not respond to or are intolerant to at least one class I or class III antiarrhythmic drug. Although radiofrequency ablation is a safe procedure, complications can occur. Depending on the location, these complications can be classified into those that affect the pulmonary veins themselves, cardiac complications, extracardiac intrathoracic complications, remote complications, and those that result from vascular access. The most common complications are hematomas, arteriovenous fistulas, and pseudoaneurysms at the puncture site. Some complications are benign and transient, such as gastroparesis or diaphragmatic elevation, whereas others are potentially fatal, such as cardiac tamponade. Radiologists must be familiar with the complications that can occur secondary to pulmonary vein ablation to ensure early diagnosis and treatment. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

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

    Science.gov (United States)

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

    2016-01-01

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

  14. Ablative zone size created by radiofrequency ablation with and without chemoembolization in small hepatocellular carcinomas.

    Science.gov (United States)

    Yamanaka, Takashi; Yamakado, Koichiro; Takaki, Haruyuki; Nakatsuka, Atsuhiro; Shiraki, Katsuya; Hasegawa, Hiroshi; Takei, Yoshiyuki; Takeda, Kan

    2012-08-01

    We retrospectively evaluated whether combined use of chemoembolization expands ablative zone sizes created by radiofrequency (RF) ablation in patients with small hepatocellular carcinomas (HCCs). Fifty-seven patients treated with single RF ablation for solitary HCC measuring ≤2 cm were assessed. RF ablation alone was done in nine patients and in 48 patients following chemoembolization, with an interval of 0 days in 6, 1-14 days in 27, 15-28 days in 6, and ≥4 weeks in 9. Ablative zone sizes, disappearance of tumor enhancement, and creation of sufficient ablative margins (>5 mm) were evaluated on contrast-enhanced computed tomography (CT) images. Both mean long-axis (4.2-4.7 vs. 3.6 ± 0.4 cm, p ablation was done until 4 weeks after chemoembolization than with RF ablation alone. Tumor enhancement disappeared in all patients. Frequency of achieving sufficient ablative margins was significantly higher when RF ablation was done until 4 weeks after chemoembolization than with RF ablation alone (74.0-83.3 vs. 22.2 %, p Ablative zones created by RF ablation with chemoembolization become larger than RF ablation alone, leading to secure ablative margins.

  15. Percutaneous Radiofrequency Ablation with Artificial Ascites for Hepatocellular Carcinoma in the Hepatic Dome: Initial Experience

    National Research Council Canada - National Science Library

    Rhim, Hyunchul; Lim, Hyo K; Kim, Young-sun; Choi, Dongil

    2008-01-01

    ...) in the hepatic dome. MATERIALS AND METHODS. Sonographically guided percutaneous radiofrequency ablation with artificial ascites was performed in 25 patients with 34 HCCs using an internally cooled electrode radiofrequency system...

  16. Radiofrequency catheter ablation for the management of cardiac tachyarrhythmias.

    Science.gov (United States)

    Wood, M; Ellenbogen, K; Stambler, B

    1993-10-01

    Radiofrequency catheter ablation techniques allow for safe and highly effective curative therapy of a variety of cardiac dysrhythmias. The technique involves the delivery of a high-frequency, alternating electrical current through an intravascular catheter to sites of arrhythmogenic myocardium. This current induces resistive electrical heating of the tissue, resulting in discrete areas of myocardial destruction through coagulation and desiccation. Dysrhythmias most commonly treated with these techniques are atrioventricular nodal reentry and tachycardias related to accessory atrioventricular bypass tracts. For these dysrhythmias, success rates of 90% to 95% are achievable with a low (2% to 4%) risk of complications. Radiofrequency catheter ablation techniques also have been used to treat ventricular tachycardias, atrial flutter, ectopic atrial tachycardia, and sinus node reentry, albeit with lower success rates. These techniques are still evolving, alternate energy sources (such as microwave and laser) and improved catheter technology should enhance the technique's safety and efficacy for a wider range of dysrhythmias.

  17. Initial radiofrequency ablation failure for hepatocellular carcinoma: repeated radiofrequency ablation versus transarterial chemoembolisation.

    Science.gov (United States)

    Kim, S S; Kang, T W; Kim, M; Lee, M W; Cho, S K; Paik, Y H; Kim, M-J

    2018-02-01

    To compare the long-term therapeutic outcomes of repeated radiofrequency ablation (RFA) with that of transarterial chemoembolisation (TACE) in patients with local tumour progression (LTP) after initial RFA treatment for hepatocellular carcinoma (HCC). This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between July 2006 and February 2012, 713 patients underwent RFA for single HCC as a first-line treatment. Fifty-eight patients who showed LTP as initial tumour recurrence post-RFA treatment were included. Patients were treated with either repeated RFA (n=33) or TACE (n=25). TACE was performed as an alternative therapeutic option when repeated RFA was not feasible based on the planning ultrasonography. Recurrence-free and overall survival rates were estimated using the Kaplan-Meier method. Prognostic factors for outcomes were evaluated using the Cox proportional hazards model. Both groups did not show significant differences in terms of baseline characteristics, with the exception being the proportion of subphrenic tumours (p=0.031). The RFA and TACE groups did not differ significantly in their 5-year recurrence-free and overall survival rates (17% versus 10.7% and 72.7% versus 51.9%, respectively, with all p-values >0.05). In addition, multivariate analyses revealed that type of treatment was not associated with recurrence-free or overall survival in patients with post-RFA LTP. TACE is an effective treatment, comparable to repeated RFA, in patients with LTP after initial RFA when repeated RFA is not feasible. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  18. Actual role of radiofrequency ablation of liver metastases

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Philippe L. [Eberhard-Karls-University of Tuebingen, Department of Diagnostic Radiology, Tuebingen (Germany)

    2007-08-15

    The liver is, second only to lymph nodes, the most common site for metastatic disease irrespective of the primary tumour. More than 50% of all patients with malignant diseases will develop liver metastases with a significant morbidity and mortality. Although the surgical resection leads to an improved survival in patients with colorectal metastases, only approximately 20% of patients are eligible for surgery. Thermal ablation and especially radiofrequency ablation emerge as an important additional therapy modality for the treatment of liver metastases. RF ablation shows a benefit in life expectancy and may lead in a selected patient group to cure. Percutaneous RF ablation appears safer (versus cryotherapy), easier (versus laser), and more effective (versus ethanol instillation and transarterial chemoembolisation) compared with other minimally invasive procedures. RF ablation can be performed by a percutaneous, laparoscopical or laparotomic approach, and may be potentially combined with chemotherapy and surgery. At present ideal candidates have tumours with a maximum diameter less than 3.5 cm. An untreatable primary tumour or a systemic disease represents contraindications for performing local therapies. Permanent technical improvements of thermal ablation devices and a better integration of thermal ablation in the overall patient care may lead to prognosis improvement in patients with liver metastases. (orig.)

  19. Clinical effect of radiofrequency ablation in treatment of hepatic hemangioma

    Directory of Open Access Journals (Sweden)

    SUN Libo

    2017-01-01

    Full Text Available ObjectiveTo investigate the clinical effect and application experience of radiofrequency ablation in the treatment of hepatic hemangioma. MethodsA retrospective analysis was performed for the clinical data of 34 patients with hepatic hemangioma who underwent radiofrequency ablation in Beijing You′an Hospital from January 2011 to June 2015. Among these patients, 22 underwent ultrasound-guided percutaneous transhepatic radiofrequency ablation (PRFA, 10 underwent laparoscopic radiofrequency ablation (LRFA, and 2 underwent open hepatectomy combined with hepatic hemangioma radiofrequency ablation (OHRFA. The intraoperative and postoperative conditions were compared between patients undergoing different methods of radiofrequency ablation. ResultsAll the patients underwent successful radiofrequency ablation. The mean time of operation in PRFA group, LRFA group, and OHRFA group was 75.45±27.33 min, 97.90±32.37 min, and 192.5 min, respectively, and the median hospital stay in these groups was 3 d, 3 d, and 10.5 d, respectively. There were no serious complications during and after surgery. The complete remission rate at 1 month after surgery was 94.1%(32/34. The patients were followed up for 6-24 months and no recurrence was observed. ConclusionRadiofrequency ablation is a safe and effective procedure for the treatment of hepatic hemangioma. Strict control of surgical indications and selection of proper radiofrequency ablation approach are of great importance.

  20. A tubular electrode for radiofrequency ablation therapy

    KAUST Repository

    Antunes, Carlos Lemos Lemos Lemos

    2012-07-06

    Purpose – Due to its good mechanical and biocompatibility characteristics, nitinol SEMS is a popular endoprothesis used for relieving stricture problems in hollow organs due to carcinomas. Besides its mechanical application, SEMS can be regarded as well as potential electrode for performing RF ablation therapy on the tumor. The purpose of this work is to perform numerical and experimental analyses in order to characterize the lesion volume induced in biological tissue using this kind of tubular electrode. Design/methodology/approach – Data concerning electrical conductivity and dimension of the damaged tissue after RF ablation procedure were obtained from ex vivo samples. Next, numerical models using 3D finite element method were obtained reassembling the conditions considered at experimentation setup and results were compared. Findings – Numerical and experimental results show that a regular volume of damaged tissue can be obtained considering this type of electrode. Also, results obtained from numerical simulation are close to those obtained by experimentation. Originality/value – SEMSs, commonly used as devices to minimize obstruction problems due to the growth of tumors, may still be considered as an active electrode for RF ablation procedures. A method considering this observation is presented in this paper. Also, numerical simulation can be regarded in this case as a tool for determining the lesion volume.

  1. [Radiofrequency catheter ablation therapy in elderly patients with supraventricular tachycardia].

    Science.gov (United States)

    Shimizu, A; Yamagata, T; Tatsuno, H; Esato, M; Ueyama, T; Hayano, T; Oomura, M; Tamura, K; Matsuzaki, M

    1998-06-01

    138 patients with Wolf-Parkinson-White (WPW) syndrome (n = 96), atrioventricular nodal reentrant tachycardia (AVNRT; n = 27) and the other supraventricular tachycardia (n = 15), were divided into two groups, a control group (less than 65 years old; n = 108) and an elderly group (more than 66 years old; n = 30). We then estimated the success rate and safety of radiofrequency ablation for supraventricular tachycardia in elderly patients. For WPW syndrome, there were 76 (97%) successes and 9 (13%) recurrences in the control group (n = 78). In the elderly group of WPW patients, the number of successes was 18 (100%) and the number of recurrences one (63%). In 27 patients with AVNRT, the number of successes was 26 (96%) and there were no recurrences. In 15 patients with some other supraventricular tachycardia, there were 11 patients (73%) successes and one recurrence (11%). Major complications consisted of cardiac tamponade in 2 patients, dissecting aneurysm in one patient and cerebral embolism in one patients. All major complications occurred in patients with WPW syndrome. The cause of the complications, except the cerebral embolism was manipulation of the electrical or ablation catheter. Three of four patients with major complications belonged to the control group. It is possible that radiofrequency catheter ablation for supraventricular tachycardia in elderly patients is safe and highly effective. However, it is still invasive therapy. Ablation on a left accessory pathway by the transaortic valve approach especially needs meticulous care.

  2. Thermometry during coblation and radiofrequency ablation of vertebral metastases: a cadaver study

    National Research Council Canada - National Science Library

    Groetz, Simon F; Birnbaum, Klaus; Meyer, Carsten; Strunk, Holger; Schild, Hans H; Wilhelm, Kai E

    2013-01-01

    To evaluate safety of coblation of simulated lytic metastases in human cadaveric vertebral bodies by measuring heat distribution during thermal tissue ablation and comparing it to radiofrequency ablation (RFA...

  3. Radiofrequency Ablation Treatment for Renal Cell Carcinoma: Early Clinical Experience

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seong Hoon; Yoon, Seong Kuk; Cho, Jin Han; Oh, Jong Young; Nam, Kyung Jin; Kwon, Hee Jin; Kim, Su Yeon; Kang, Myong Jin; Choi, Sun Seob; Sung, Gyung Tak [Dong-A University College of Medicine, Busan (Korea, Republic of)

    2008-08-15

    To evaluate the early clinical experience associated with radiofrequency (RF) ablation in patients with renal cell carcinoma (RCC). The RF ablation treatment was performed on 17 tumors from 16 patients (mean age, 60.5 years; range, 43 73 years) with RCC. The treatment indications were localized, solid renal mass, comorbidities, high operation risk, and refusal to perform surgery. All tumors were treated by a percutaneous CT (n = 10), followed by an US-guided (n = 2), laparoscopy-assisted US (n = 2), and an open (n = 2) RF ablation. Furthermore, patients underwent a follow- up CT at one day, one week, one month, three and six months, and then every six months from the onset of treatment. We evaluated the technical success, technical effectiveness, ablation zone, benign periablation enhancement, irregular peripheral enhancement, and complications. All 17 exophytic tumors (mean size, 2.2 cm; range, 1.1 5.0 cm) were completely ablated. Technical success and effectiveness was achieved in all cases and the mean follow-up period was 23.8 months (range, 17 33 months). A local recurrence was not detected in any of the cases; however, five patients developed complications as a result of treatment, including hematuria (n = 2), mild thermal injury of the psoas muscle (n = 1), mild hydronephrosis (n = 1), and fistula formation (n = 1). The RF ablation is an alternative treatment for exophytic RCCs and represents a promising treatment for some patients with small RCCs.

  4. Radiofrequency thermal ablation of malignant hepatic tumors: post-ablation syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung Bin; Rhim, Hyunchul; Kim, Yongsoo; Koh, Byung Hee; Cho, On Koo; Seo, Heung Suk; Lee, Seung Ro [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    2000-07-01

    To evaluate post-ablation syndrome after radiofrequency thermal ablation of malignant hepatic tumors. Forty-two patients with primary (n=3D29) or secondary (n=3D13) hepatic tumors underwent radiofrequency thermal ablation. A total of 65 nodules ranging in size from 1.1 to 5.0 (mean, 3.1) cm were treated percutaneously using a 50W RF generator with 15G expandable needle electrodes. We retrospectively evaluated the spectrum of post-ablation syndrome including pain, fever ({>=}3D 38 deg C), nausea, vomiting, right shoulder pain, and chest discomfort according to frequency, intensity and duration, and the findings were correlated with tumor location and number of ablations. We also evaluated changes in pre-/post-ablation serum aminotransferase (ALT/AST) and prothrombin time, and correlated these findings with the number of ablations. Post-ablation syndrome was noted in 29 of 42 patients (69.0%), and most symptoms improved with conservative treatment. The most important of these were abdominal plan (n=3D20, 47.6%), fever (n=3D8, 19.0%), and nausea (n=3D7, 16.7%), and four of 42 (9.5%) patients complained of severe pain. The abdominal pain lasted from 3 hours to 5.5 days (mean; 20.4 hours), the fever from 6 hours to 5 days (mean; 63.0 hours). And the nausea from 1 hours to 4 days (mean; 21.0 hours). Other symptoms were right shoulder pain (n=3D6, 14.3%), chest discomfort (n=3D3, 7.1%), and headache (n=3D3, 7.1%). Seventeen of 20 patients (85%) with abdominal pain had subcapsular tumor of the liver. There was significant correlation between pain, location of the tumor, and a number of ablations. After ablation, ALT/AST was elevated more than two-fold in 52.6%/73.7% of patients, respectively but there was no significant correlation with the number of ablation. Post-ablation syndrome is a frequent and tolerable post-procedural process after radiofrequency thermal ablation. The spectrum of this syndrome provides a useful guideline for the post-ablation management. (author)

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

    Science.gov (United States)

    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.

  6. Radiofrequency catheter ablation for atrial flutter following orthotopic heart transplantation

    Science.gov (United States)

    Pitt, M; Bonser, R; Griffith, M

    1998-01-01

    A 26 year old woman with a diagnosis of limb girdle muscular dystrophy and peripartum cardiomyopathy underwent orthotopic heart transplantation using standard atrial anastomoses. Recurrent atrial flutter was demonstrated in the absence of histological evidence of cellular rejection. Radiofrequency ablation of the flutter circuit was successfully performed allowing the avoidance of long term antiarrhythmic therapy. Ten weeks following ablation and cessation of amiodarone, presyncopal symptoms were found, associated with daytime and nocturnal sinus pauses of 2.9 seconds and 4.2 seconds, respectively. There was no evidence of AV node conduction impairment. In view of the continued absence of cellular rejection and the evident denervated state of the heart, the pauses reflected significant donor sinus node dysfunction; therefore, an AAIR permanent pacing system was implanted. At the time of pacemaker implantation atrial pacing at 150 beats/min did not produce significant PR interval prolongation or AV block. This case serves to advise rigorous follow up in such patients to continue to seek evidence of sinus node dysfunction potentially requiring permanent pacemaker implantation.

 Keywords: heart transplantation;  atrial flutter;  radiofrequency catheter ablation PMID:9616353

  7. Therapeutic efficacy of percutaneous radiofrequency ablation versus microwave ablation for hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    Full Text Available The aim of this study was to investigate the therapeutic efficacy of percutaneous radiofrequency (RF ablation versus microwave (MW ablation for hepatocellular carcinoma (HCC measuring ≤ 5 cm in greatest diameter. From January 2006 to December 2006, 78 patients had undergone RF ablation whereas 77 had undergone MW ablation. Complete ablation (CA, local tumour progression (LTP and distant recurrence (DR were compared. The overall survival curves were calculated with the Kaplan-Meier technique and compared with the log-rank test. The CA rate was 83.4% (78/93 for RF ablation and 86.7%(91/105 for MW ablation. The LTP rate was 11.8% (11/93 for RF ablation and 10.5% (11/105 for MW ablation. DR was found in 51 (65.4% in the RF ablation and 62 (80.5% in the MW ablation. There was no significant difference in the 1-, 3-, and 5-year overall survival rates (P = 0.780 and the 1-, 3-, and 5-year disease-free survival rates (P = 0.123 between RF and MW ablation. At subgroup analyses, for patients with tumors ≤ 3.0 cm, there was no significant difference in the 1-, 3-, and 5-year overall survival rates (P = 0.067 and the corresponding disease-free survival rates(P = 0.849. For patients with tumor diameters of 3.1-5.0 cm, the 1-, 3-, and 5-year overall survival rates were 87.1%, 61.3%, and 40.1% for RF ablation and 85.4%, 36.6%, and 22% for MW ablation, with no significant difference (P = 0.068. The corresponding disease-free survival rates were 74.2%, 54.8%, and 45.2% for the RF ablation group and 53.3%, 26.8%, and 17.1% for the MW ablation group. The disease-free survival curve for the RF ablation group was significantly better than that for the MW ablation group (P = 0.018. RF ablation and MW ablation are both effective methods in treating hepatocellular carcinomas, with no significant differences in CA, LTP, DR, and overall survival.

  8. Incidence and Cause of Hypertension During Adrenal Radiofrequency Ablation

    Energy Technology Data Exchange (ETDEWEB)

    Yamakado, Koichiro, E-mail: yama@clin.medic.mie-u.ac.jp; Takaki, Haruyuki [Mie University School of Medicine, Department of Interventional Radiology (Japan); Yamada, Tomomi [Mie University School of Medicine, Department of Translational Medicine (Japan); Yamanaka, Takashi; Uraki, Junji; Kashima, Masataka; Nakatsuka, Atsuhiro; Takeda, Kan [Mie University School of Medicine, Department of Interventional Radiology (Japan)

    2012-12-15

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

  9. Role of percutaneous ultrasonographic guided radiofrequency ablation in the management of hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed Youssef

    2014-06-01

    Conclusion: Radiofrequency thermal ablation is a simple, effective and less expensive technique with a low morbidity compared with surgical treatment. Radiofrequency thermal ablation can produce significant long-term survival rates and excellent local control for cirrhotic patients with early stage, unresectable HCC.

  10. Factors Influencing Lesion Formation During Radiofrequency Catheter Ablation

    Directory of Open Access Journals (Sweden)

    Olaf J. Eick

    2003-07-01

    Full Text Available In radiofrequency (RF ablation, the heating of cardiac tissue is mainly resistive. RF current heats cardiac tissue and in turn the catheter electrode is being heated. Consequently, the catheter tip temperature is always lower - or ideally equal - than the superficial tissue temperature. The lesion size is influenced by many parameters such as delivered RF power, electrode length, electrode orientation, blood flow and tissue contact. This review describes the influence of these different parameters on lesion formation and provides recommendations for different catheter types on selectable parameters such as target temperatures, power limits and RF durations

  11. Thyroid radiofrequency ablation: Updates on innovative devices and techniques

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hye Sun; Baek, Jung Hwan; Chung, Sae Rom; Choi, Young Jun; Lee, Jeong Hyun [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Park, Auh Whan [Dept. of Radiology, Vascular and Interventional Radiology Section, University of Virginia Health System, Charlottesville (United States)

    2017-08-01

    Radiofrequency ablation (RFA) is a well-known, effective, and safe method for treating benign thyroid nodules and recurrent thyroid cancers. Thyroid-dedicated devices and basic techniques for thyroid RFA were introduced by the Korean Society of Thyroid Radiology (KSThR) in 2012. Thyroid RFA has now been adopted worldwide, with subsequent advances in devices and techniques. To optimize the treatment efficacy and patient safety, understanding the basic and advanced RFA techniques and selecting the optimal treatment strategy are critical. The goal of this review is to therefore provide updates and analysis of current devices and advanced techniques for RFA treatment of benign thyroid nodules and recurrent thyroid cancers.

  12. Efficacy of percutaneous radiofrequency ablation of osteoid osteoma in children

    Energy Technology Data Exchange (ETDEWEB)

    Donkol, Ragab H. [Cairo University, Department of Radiology, Faculty of Medicine, Cairo (Egypt); Assir Central Hospital, Department of Radiology, P.O. Box 34, Abha (Saudi Arabia); Al-Nammi, Ahmed [Assir Central Hospital, Department of Radiology, P.O. Box 34, Abha (Saudi Arabia); Moghazi, Khaled [Alexandria University, Faculty of Medicine, Alexandria (Egypt)

    2008-02-15

    Percutaneous radiofrequency (RF) ablation of osteoid osteoma has high technical and clinical success rates. However, there are limited data on its use in the treatment of osteoid osteoma in children. To assess the safety and efficacy of CT-guided percutaneous RF ablation of osteoid osteoma in children and compare the outcomes with published data on its use in patients unselected for age. From January 2003 to July 2006, 23 children with osteoid osteoma were treated with CT-guided RF ablation using a straight rigid electrode. Their mean age was 11 years (range 3.5-16 years) and there were 15 boys and 8 girls. The procedures were carried out under general anaesthesia. Follow-up was performed to assess technical and clinical outcome. The mean follow-up period was 2.5 years (range 13-49 months). Technical success was achieved in 21 children (91.3%). Failure occurred in two children, in one due to failure to adequately localize the nidus within the dense sclerosis and in the other because of a short ablation time (2 min) because he developed hyperthermia. Clinical success was achieved in 18 patients within 2-5 days (primary clinical success rate 78.2%).These patients were allowed to fully weight-bear and function without limitation 1 week after the procedure. Pain recurrence was observed in two patients; one was treated successfully with a second ablation after 6 months (secondary clinical success rate 82.6%). Hyperthermia was observed in two patients during the procedure. Three other minor complications were observed: wound infection in one child and skin burn in two children. No major immediate or delayed complications were observed. Percutaneous CT-guided RF ablation is an effective and safe minimally invasive procedure for the treatment of osteoid osteoma in children. It has high technical and clinical success rates that are slightly lower than those of patients with a wider range of ages. (orig.)

  13. Radiofrequency Ablation of Hepatocellular Carcinoma: A Literature Review

    Directory of Open Access Journals (Sweden)

    Yasunori Minami

    2011-01-01

    Full Text Available Radiofrequency ablation (RFA of liver cancers can be performed safely using percutaneous, laparoscopic, or open surgical techniques, and much of the impetus for the use of RFA has come from cohort series that have provided an evidence base for this technique. Here, we give an overview of the current status of radiofrequency ablation (RFA for hepatocellular carcinoma (HCC, including its physical properties, to assess the characteristics that make this technique applicable in clinical practice. We review the technical development of probe design and summarize current indications and outcomes of reported clinical use. An accurate evaluation of treatment response is very important to secure successful RFA therapy since a sufficient safety margin (at least 0.5 cm can prevent local tumor recurrences. We also provide a profile of side effects and information on the integration of this technique into the general management of patients with HCC. To minimize complications of RFA, physicians should be familiar with each feature of complication. Appropriate management of complications is essential for successful RFA treatment. Moreover, adjuvant therapy, such as molecular targeted therapies following curative therapy, is expected to further improve survival after RFA.

  14. Interactive multi-criteria planning for radiofrequency ablation.

    Science.gov (United States)

    Schumann, Christian; Rieder, Christian; Haase, Sabrina; Teichert, Katrin; Süss, Philipp; Isfort, Peter; Bruners, Philipp; Preusser, Tobias

    2015-06-01

    Image-guided radiofrequency ablation (RFA) is a broadly used minimally invasive method for the thermal destruction of focal liver malignancies using needle-shaped instruments. The established planning workflow is based on examination of 2D slices and manual definition of the access path. During that process, multiple criteria for all possible trajectories have to be taken into account. Hence, it demands considerable experience and constitutes a significant mental task. An access path determination method based on image processing and numerical optimization is proposed. Fast GPU-based simulation approximation is utilized to incorporate the heat distribution including realistic cooling effects from nearby blood vessels. A user interface for intuitive exploration of the optimization results is introduced. The proposed methods are integrated into a clinical software assistant. To evaluate the suitability of the interactive optimization approach for the identification of meaningful therapy strategies, a retrospective study has been carried out. The system is able to propose clinically relevant trajectories to the target by incorporating multiple criteria. A novel method for planning of image-guided radiofrequency ablation by means of interactive access path determination based on optimization is presented. A first retrospective study indicates that the method is suited to improve the classical planning of RFA.

  15. Noninvasive assessment of tissue heating during cardiac radiofrequency ablation using MRI thermography.

    Science.gov (United States)

    Kolandaivelu, Aravindan; Zviman, Menekhem M; Castro, Valeria; Lardo, Albert C; Berger, Ronald D; Halperin, Henry R

    2010-10-01

    Failure to achieve properly localized, permanent tissue destruction is a common cause of arrhythmia recurrence after cardiac ablation. Current methods of assessing lesion size and location during cardiac radiofrequency ablation are unreliable or not suited for repeated assessment during the procedure. MRI thermography could be used to delineate permanent ablation lesions because tissue heating above 50°C is the cause of permanent tissue destruction during radiofrequency ablation. However, image artifacts caused by cardiac motion, the ablation electrode, and radiofrequency ablation currently pose a challenge to MRI thermography in the heart. In the current study, we sought to demonstrate the feasibility of MRI thermography during cardiac ablation. An MRI-compatible electrophysiology catheter and filtered radiofrequency ablation system was used to perform ablation in the left ventricle of 6 mongrel dogs in a 1.5-T MRI system. Fast gradient-echo imaging was performed before and during radiofrequency ablation, and thermography images were derived from the preheating and postheating images. Lesion extent by thermography was within 20% of the gross pathology lesion. MR thermography appears to be a promising technique for monitoring lesion formation and may allow for more accurate placement and titration of ablation, possibly reducing arrhythmia recurrences.

  16. Noninvasive Assessment of Tissue Heating During Cardiac Radiofrequency Ablation Using MRI Thermography

    Science.gov (United States)

    Kolandaivelu, Aravindan; Zviman, Menekhem M.; Castro, Valeria; Lardo, Albert C.; Berger, Ronald D.; Halperin, Henry R.

    2010-01-01

    Background Failure to achieve properly localized, permanent tissue destruction is a common cause of arrhythmia recurrence after cardiac ablation. Current methods of assessing lesion size and location during cardiac radiofrequency ablation are unreliable or not suited for repeated assessment during the procedure. MRI thermography could be used to delineate permanent ablation lesions because tissue heating above 50°C is the cause of permanent tissue destruction during radiofrequency ablation. However, image artifacts caused by cardiac motion, the ablation electrode, and radiofrequency ablation currently pose a challenge to MRI thermography in the heart. In the current study, we sought to demonstrate the feasibility of MRI thermography during cardiac ablation. Methods and Results An MRI-compatible electrophysiology catheter and filtered radiofrequency ablation system was used to perform ablation in the left ventricle of 6 mongrel dogs in a 1.5-T MRI system. Fast gradient-echo imaging was performed before and during radiofrequency ablation, and thermography images were derived from the preheating and postheating images. Lesion extent by thermography was within 20% of the gross pathology lesion. Conclusions MR thermography appears to be a promising technique for monitoring lesion formation and may allow for more accurate placement and titration of ablation, possibly reducing arrhythmia recurrences. PMID:20657028

  17. Midterm outcome of radiofrequency thermal ablation for symptomatic uterine myomas.

    Science.gov (United States)

    Ghezzi, Fabio; Cromi, Antonella; Bergamini, Valentino; Scarperi, Stefano; Bolis, Pierfrancesco; Franchi, Massimo

    2007-11-01

    Over the past decade an increasing demand for uterine-sparing treatment to manage symptomatic uterine myomas has become apparent in women's health care. A preliminary report showed that radiofrequency ablation (RFA) of uterine fibroids under laparoscopic guidance was a safe and effective minimally invasive approach with encouraging short-term results. The purpose of this study was to evaluate the midterm outcomes of radiofrequency ablation (RFA) of uterine myomas in terms of durability of symptom control and level of health-related quality of life. Consecutive women with symptomatic uterine myomas, no plans for future pregnancy, and who declined hysterectomy were offered RFA ablation of uterine fibroids under laparoscopic guidance. Only 25 patients who completed at least the one-year follow-up assessment were included in the study group. Follow-up evaluations were scheduled at 1, 3, 6, 9, and 12 months and thereafter annually following the procedure. Improvement in myoma-related symptoms and impact on quality of life were assessed using a validated questionnaire (UFS-QOL). The median number of myomas treated per patient was 1 (range = 1-3). The median baseline volume of the dominant myoma was 76.8 cm3 (range = 14.8-332.8). No intraoperative or postoperative complications occurred. The median follow-up time was 24 months, with nine women completing three years of follow-up. The median reduction in myoma volume was 68.8% and 77.9% at six months and one year, respectively. No further change in fibroid size was observed at two years and three years. One year after the procedure, one woman (4%) underwent hysterectomy for recurrence of fibroid-related symptoms. Quality-of-life measures showed significant and durable improvement compared with baseline. RFA of symptomatic fibroids seems a valuable alternative to major surgery, with durable symptom relief for most patients and a low chance of recurrence at midterm.

  18. Stereotactic Radiofrequency Ablation for Metastatic Melanoma to the Liver

    Energy Technology Data Exchange (ETDEWEB)

    Bale, Reto, E-mail: reto.bale@i-med.ac.at; Schullian, Peter [Medical University Innsbruck, Department of Radiology, Section of Interventional Oncology - Microinvasive Therapy (SIP) (Austria); Schmuth, Matthias [Medical University Innsbruck, Department of Dermatology (Austria); Widmann, Gerlig; Jaschke, Werner [Medical University Innsbruck, Department of Radiology, Section of Interventional Oncology - Microinvasive Therapy (SIP) (Austria); Weinlich, Georg [Medical University Innsbruck, Department of Dermatology (Austria)

    2016-08-15

    PurposeTo evaluate the outcome of patients with melanoma liver metastasis treated with stereotactic radiofrequency ablation (SRFA).Material and MethodFollowing IRB approval, a retrospective evaluation of the treatment of 20 patients with 75 melanoma liver metastases was performed.ResultsA median number of 2 lesions (range 1–14) per patient with a median size of 1.7 cm (range 0.5–14.5 cm) were treated. 67 lesions were <3 cm (89.3 %) and 8 lesions were >3 cm (10.7 %). Per patient a median of 1 ablation session was performed (range: 1–4) totaling 34 sessions. There were no procedure-related deaths and all major complications (n = 3) could be easily treated by pleural drainages. The primary and secondary success rates were 89.3 and 93.3 %, respectively. The overall local recurrence rate was 13.3 %. Four of ten local recurrences were re-treated successfully by SRFA. During follow-up, 9/20 patients developed extrahepatic metastatic disease and 10/20 had liver recurrence at any location. The median OS from the date of SRFA was 19.3 months, with an OS of 64, 41, and 17 % at 1, 3, and 5 years, with no significant difference for patients with cutaneous and ocular melanoma. The median DFS after SRFA for all 20 patients was 9.5 months, with 37, 9, and 0 % at 1, 3, and 5 years.ConclusionsDue to the high local curative potential and the promising long-term survival rates associated with minimal morbidity and mortality, radiofrequency ablation seems to be an attractive alternative to resection in patients with melanoma liver metastases.

  19. Radiofrequency ablation of liver metastases; Radiofrequenzablation von Lebermetastasen

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, P.L.; Clasen, S.; Schmidt, D.; Wiskirchen, J.; Tepe, G.; Claussen, C.D. [Abt. fuer Radiologische Diagnostik, Eberhard-Karls-Univ. Tuebingen (Germany); Boss, A. [Abt. fuer Radiologische Diagnostik, Eberhard-Karls-Univ. Tuebingen (Germany); Sektion fuer Experimentelle Radiologie der Abt. fuer Radiologische Diagnostik, Eberhard-Karls-Univ. Tuebingen (Germany); Gouttefangeas, C. [Abt. Immunologie des Inst. fuer Zellbiologie, Eberhard-Karls-Univ. Tuebingen (Germany); Burkart, C. [Zentrum fuer gastroenterologische Onkologie der Medizinischen Klinik, Eberhard-Karls-Univ. Tuebingen (Germany)

    2004-04-01

    The liver is the second only to lymph nodes as the most common site of metastatic disease irrespective of the primary tumor. Up to 50% of all patients with malignant diseases will develop liver metastases with a significant morbidity and mortality. Although the surgical resection leads to an improvement of the survival time, only approximately 20% of the patients are eligible for surgical intervention. Radiofrequency (RF) ablation represents one of the most important alternatives as well as complementary methods for the therapy of liver metastases. RF ablation can lead in a selected patient group to a palliation or to an increased life expectancy. RF ablation appears either safer (vs. cryotherapy) or easier (vs. laser) or more effective (percutaneous ethanol instillation [PEI]), transarterial chemoembolisation [TACE] in comparison with other minimal invasive procedures. RF ablation can be performed percutaneously, laparoscopically or intraoperatively and may be combined with chemotherapy as well as with surgical resection. Permanent technical improvements of RF systems, a better understanding of the underlying electrophysiological principles and an interdisciplinary approach will lead to a prognosis improvement in patients with liver metastases. (orig.) [German] Die Leber ist unabhaengig vom Primaertumor nach den Lymphknoten die zweithaeufigste Lokalisation von Metastasen. Bis zu 50% aller Patienten mit malignen Erkrankungen werden im Verlauf ihrer Erkrankung Lebermetastasen entwickeln, die mit einer signifikanten Morbiditaet und Mortalitaet verbunden sind. Obwohl die chirurgische Resektion zu einer verlaengerten Ueberlebenszeit fuehrt, sind nur ca. 20% der Patienten fuer einen chirurgischen Eingriff geeignet. Die Radiofrequenz-(RF-)Ablation stellt derzeit eine der effektivsten Alternativen und komplementaeren Methoden bei der Therapie von Lebermetastasen dar. In einem selektierten Patientengut fuehrt die RF-Ablation ueber den palliativen Einsatz hinaus zu einer

  20. Bilateral Intra-Articular Radiofrequency Ablation for Cervicogenic Headache

    Directory of Open Access Journals (Sweden)

    Charles A. Odonkor

    2017-01-01

    Full Text Available Introduction. Cervicogenic headache is characterized by unilateral neck or face pain referred from various structures such as the cervical joints and intervertebral disks. A recent study of patients with cervical pain showed significant pain relief after cervical medial branch neurotomy but excluded patients with C1-2 joint pain. It remains unclear whether targeting this joint has potential for symptomatic relief. To address this issue, we present a case report of C1-2 joint ablation with positive outcomes. Case Presentation. A 27-year-old female presented with worsening cervicogenic headache. Her pain was 9/10 by visual analog scale (VAS and described as cramping and aching. Pain was localized suboccipitally with radiation to her jaw and posterior neck, worse on the right. Associated symptoms included clicking of her temporomandibular joint, neck stiffness, bilateral headaches with periorbital pain, numbness, and tingling. History, physical exam, and diagnostic studies indicated localization to the C1-2 joint with 80% decrease in pain after C1-2 diagnostic blocks. She underwent bilateral intra-articular radiofrequency ablation of the C1-C2 joint. Follow-up at 2, 4, 8, and 12 weeks showed improved function and pain relief with peak results at 12 weeks. Conclusion. Clinicians may consider C1-C2 joint ablation as a viable long-term treatment option for cervicogenic headaches.

  1. [Transvesical radiofrequency needle ablation on prostatic benign hyperplasia].

    Science.gov (United States)

    Arustamov, D L; Mukhtarov, Sh T; Arustamov, L D

    2000-01-01

    Transurethral needle ablation (TUNA) of the prostate is an effective method of thermal treatment of patients with benign prostatic hyperplasia (BPH). Suprapubic transvesical access was used in order to extend indications for interstitial application of radiofrequency energy. Transvesical needle ablation (TVNA) was performed in 89 patients with BPH under conditions of chronic ischuria or in the presence of a suprapubic cystostoma. A cystoscope with an attachment for fixation and insertion of a needle electrode into prostatic tissue is inserted into the bladder through a newly created or adapted suprapubic access. The position of the needle is monitored by transurethral sonography. The ablation protocol is virtually the same as transurethral. Spontaneous urination normalized in 63 (70.8%) patients within 12 months. I-PSS, Qol, Qmax, RU, and PQmax improved. The prostate volume decreased by 1-.5%. TVNA is more effective than TUNA as a less invasive method which allows interventions under local anesthesia; there are virtually no contraindications to the use of TVNA and in many patients it can be performed in an outpatient setting.

  2. Innovative techniques for image-guided ablation of benign thyroid nodules: Combined ethanol and radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hye Sun; Baek, Jung Hwan; Choi, Young Jun; Lee, Jeong Hyun [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2017-06-15

    In the treatment of benign thyroid nodules, ethanol ablation (EA), and radiofrequency ablation (RFA) have been suggested for cystic and solid thyroid nodules, respectively. Although combining these ablation techniques may be effective, no guidelines for or reviews of the combination have been published. Currently, there are three ways of combining EA and RFA: additional RFA is effective for treatment of incompletely resolved symptoms and solid residual portions of a thyroid nodule after EA. Additional EA can be performed for the residual unablated solid portion of a nodule after RFA if it is adjacent to critical structures (e.g., trachea, esophagus, and recurrent laryngeal nerve). In the concomitant procedure, ethanol is injected to control venous oozing after aspiration of cystic fluid prior to RFA of the remaining solid nodule.

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

    Science.gov (United States)

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

    2016-01-01

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

  4. Assessment of ablative margin by unenhanced magnetic resonance imaging after radiofrequency ablation for hepatocellular carcinoma.

    Science.gov (United States)

    Koda, Masahiko; Tokunaga, Shiho; Miyoshi, Kennichi; Kishina, Manabu; Fujise, Yuki; Kato, Jun; Matono, Tomomitsu; Okamoto, Kinya; Murawaki, Yoshikazu; Kakite, Suguru

    2012-10-01

    The aim of this study was to evaluate the feasibility of magnetic resonance imaging (MRI) without a contrast agent to visualize the ablative margin after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), compared with enhanced CT. Twenty-five HCCs in 19 patients were treated by RFA. T1-weighted MRI was performed before and after RFA, and the signal intensities of the tumors and surrounding liver tissues were measured. Treatment efficacy was assessed based on three grades: margin (+), a continuous high-intensity rim around the index tumor; margin zero, a partially discontinuous high-intensity rim; margin (-), the tumor extends beyond the high-intensity rim. Twelve (86%) of fourteen low-intensity tumors on the pre-MRI were visualized as low-intensity tumors on post-MRI, and the ablative margins were visualized as high-intensity rims. Two (67%) of three high-intensity tumors on pre-MRI were visualized as higher-intensity tumors in the high-intensity ablative margin. Because the signal intensities of tumors and surrounding tissues in 14 tumors that were low- or high-intensity tumors on pre-MRI increased to the same extent, the tumors and ablative margin could be distinguished on post images. In 6 (75%) of the 8 iso-intensity tumors on pre-MRI, the ablative margin and tumor could also not be discriminated on post-MRI. The overall agreement between MRI and CT for the ablative margin was good (κ coefficient=0.716, p=0.00002). In 82% of low- or high-intensity tumors on pre-MRI, post-MRI without a contrast agent enabled visualization of the ablative margin as a high-intensity rim, and it was possible to evaluate the ablative margin earlier and easier than with enhanced CT. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Percutaneous selective radiofrequency nerve ablation for glabellar frown lines.

    Science.gov (United States)

    Kim, Jun Hyung; Jeong, Jin Wook; Son, Daegu; Han, Kihwan; Lee, So Young; Choi, Tae Hyun; Chang, David W

    2011-09-01

    The dynamic muscles of the glabellar region can be overactive, giving patients a "scowling" look and making them appear angry, worried, or stressed. The authors describe percutaneous selective nerve ablation, a minimally-invasive procedure for treatment of glabellar frown lines, and report results from a series of patients treated with the technique. From November 2007 to December 2009, 27 patients (22 women and five men) underwent percutaneous selective nerve ablation to improve glabellar frown lines. Initially, the surface pathway of the nerve to the corrugator supercilii and procerus was checked with a peripheral nerve stimulator. For percutaneous localization, a 22-gauge monopolar electrode was introduced into the lateral brow and cheek skin without incision. Short electrical stimulation (0.3-0.5 mA) was delivered to identify the proper lesion sites. Synchronous contraction of corrugator supercilii was elicited and radiofrequency nerve ablation performed (85°C, 70 seconds). In all patients, the frontal branch of the facial nerve and angular nerve were treated bilaterally. The improvement was evaluated with the Wrinkle Assessment Scale. Mean patient age was 54.5 years, and mean follow-up time was 18 months (range, 12-26 months). One patient had superficial second-degree burns to the brow skin, which healed with conservative treatment. Two patients had temporary paresthesia that completely resolved in a few weeks without sequelae. The Wrinkle Assessment Scale indicated a statistically significant improvement in the glabellar frown lines (preoperative vs postoperative mean, 3.7 vs 1.8; P safety and efficacy of percutaneous selective nerve ablation.

  6. Adaptive ultrasound temperature imaging for monitoring radiofrequency ablation.

    Directory of Open Access Journals (Sweden)

    Yi-Da Liu

    Full Text Available Radiofrequency ablation (RFA has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15 were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA.

  7. Low power radiofrequency ablation for symptomatic microcystic lymphatic malformation of the tongue.

    Science.gov (United States)

    Ryu, Nam-Gyu; Park, Sang Kyu; Jeong, Han-Sin

    2008-11-01

    Although many head and neck surgeons agree that complete surgical excision is the treatment of choice for lymphatic malformation, the infiltrating nature of microcystic lymphatic malformations and the involvement of vital structures of the head and neck make total removal nearly impossible in most cases. Recently radiofrequency ablation was introduced for the treatment of microcystic lymphatic malformations of the oral cavity; it destroys lesion tissues at low temperature (40-70 degrees C) with minimal damage to adjacent structures. However, high energy (800-1200 J) and general anesthesia for radiofrequency ablation can hinder the easy and repetitive application of radiofrequency to patients. To overcome this limitation of radiofrequency ablation for microcystic lymphatic malformations, we used the same technique with a lower power (6 W, less than 100 J per site) radiofrequency ablation in an office-based setting under local anesthesia in a child with a microcystic lymphatic malformation of the whole tongue, that was associated with recurrent bleeding and swelling. The repetitive low power energy radiofrequency ablation of the microcystic lymphatic malformation of the tongue was safe and effective; it provided the patient with symptomatic relief without recurrence at follow-up. Therefore, our modification of radiofrequency ablation of the microcystic lymphatic malformations could be technically feasible and easily applicable; our result suggests that it can be a useful alternative treatment option to relieve symptoms from microcystic lymphatic malformation of the oral cavity.

  8. Radiofrequency ablation for pulmonary metastases from gastrointestinal cancers.

    Science.gov (United States)

    Baba, Yoshifumi; Watanabe, Masayuki; Yoshida, Naoya; Kawanaka, Koichi; Yamashita, Yasuyuki; Baba, Hideo

    2014-01-01

    The lung is one of the most common targets of metastases from gastrointestinal (GI) cancers. Surgical treatment (i.e., metastasectomy) is an accepted therapeutic option for pulmonary metastases from GI cancers. However, surgery may be contraindicated in advanced stages of cancer, compromised lung function, and/or comorbidities. This issue has prompted the search for innovative and less invasive ways of treating pulmonary metastases. Image-guided radiofrequency ablation (RFA) has attracted great interest as a minimally invasive approach against intrathoracic malignancies. In this technique, radiofrequency energy is applied via a needle electrode inserted into the target tissue. As the cells are agitated by the applied energy, they release heat, causing denaturation and cell death. Recently, this technique has been used on patients with pulmonary metastatic disease arising from GI cancers such as colorectal cancer, esophageal cancer, and hepatocellular carcinoma, as well as on patients with primary lung cancer. The present review updates the clinical outcomes and advances in RFA therapy of lung metastases from GI cancers.

  9. Lesion dimensions during temperature-controlled radiofrequency catheter ablation of left ventricular porcine myocardium: impact of ablation site, electrode size, and convective cooling

    DEFF Research Database (Denmark)

    Høgh Petersen, H; Chen, X; Pietersen, A

    1999-01-01

    It is important to increase lesion size to improve the success rate for radiofrequency ablation of ischemic ventricular tachycardia. This study of radiofrequency ablation, with adjustment of power to approach a preset target temperature, ie, temperature-controlled ablation, explores the effect of...

  10. Optimal approach for complete liver tumor ablation using radiofrequency ablation: a simulation study.

    Science.gov (United States)

    Givehchi, Sogol; Wong, Yin How; Yeong, Chai Hong; Abdullah, Basri Johan Jeet

    2018-04-01

    To investigate the effect of radiofrequency ablation (RFA) electrode trajectory on complete tumor ablation using computational simulation. The RFA of a spherical tumor of 2.0 cm diameter along with 0.5 cm clinical safety margin was simulated using Finite Element Analysis software. A total of 86 points inside one-eighth of the tumor volume along the axial, sagittal and coronal planes were selected as the target sites for electrode-tip placement. The angle of the electrode insertion in both craniocaudal and orbital planes ranged from -90° to +90° with 30° increment. The RFA electrode was simulated to pass through the target site at different angles in combination of both craniocaudal and orbital planes before being advanced to the edge of the tumor. Complete tumor ablation was observed whenever the electrode-tip penetrated through the epicenter of the tumor regardless of the angles of electrode insertion in both craniocaudal and orbital planes. Complete tumor ablation can also be achieved by placing the electrode-tip at several optimal sites and angles. Identification of the tumor epicenter on the central slice of the axial images is essential to enhance the success rate of complete tumor ablation during RFA procedures.

  11. [A new method of radiofrequency needle ablation of the prostate in the treatment of benign hyperplasia].

    Science.gov (United States)

    Mukhtarov, Sh T; Arustamov, D L

    2002-01-01

    The authors present the results of a new transvesical approach for radiofrequency needle ablation of the prostate in 29 patients with benign prostatic hyperplasia (BPH). The ablation has been done using a new radiofrequency generator ESHFG-440-40-1 made in Russia. Upon 12-month follow-up urination normalized in 23 patients. This result is better than that after transurethral needle ablation. The transvesical needle ablation has no contradictions and can be used in a wide range of patients with BPH both in hospital and outpatient settings.

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

    Directory of Open Access Journals (Sweden)

    Vora Amit

    2009-01-01

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

  13. Radiofrequency (thermal) ablation versus no intervention or other interventions for hepatocellular carcinoma

    DEFF Research Database (Denmark)

    Weis, Sebastian; Franke, Annegret; Mössner, Joachim

    2013-01-01

    Hepatocellular carcinoma is the fifth most common cancer worldwide. Percutaneous interventional therapies, such as radiofrequency (thermal) ablation (RFA), have been developed for early hepatocellular carcinoma. RFA competes with other interventional techniques such as percutaneous ethanol...

  14. Radiofrequency Ablation: A Minimally Invasive Approach in Kidney Tumor Management

    Energy Technology Data Exchange (ETDEWEB)

    Salagierski, Maciej, E-mail: maciej.salagierski@umed.lodz.pl [I Urology Department, Medical University of Lodz (Poland); Salagierski, Marek S. [II Urology Department, Medical University of Lodz (Poland)

    2010-11-17

    The management and diagnosis of renal tumors have changed significantly over the last decade. Due to advances in imaging techniques, more than 50% of kidney tumors are discovered incidentally and many of them represent an early stage lesion. This has stimulated the development of nephron-sparing surgery and of the minimally invasive treatment options including ablative techniques, i.e., radiofrequency ablation (RFA) and cryoablation. The objective of the minimally invasive approach is to preserve the renal function and to lower the perioperative morbidity. RFA involves inducing the coagulative necrosis of tumor tissue. Being probably one of the least invasive procedures in kidney tumor management, RFA may be performed percutaneously under ultrasound (US), computed tomography (CT) or magnetic resonance (MR) guidance. Most of the studies show that the RFA procedure is efficient, safe and has a low complication rate. Due to the still limited data on the oncological outcome of RFA, the indication for this intervention remains limited to selected patients with small organ-confined renal tumors and contraindication to surgery or who have a solitary kidney. The aim of our study is to review the literature on RFA of kidney tumors.

  15. Polarization image segmentation of radiofrequency ablated porcine myocardial tissue.

    Directory of Open Access Journals (Sweden)

    Iftikhar Ahmad

    Full Text Available Optical polarimetry has previously imaged the spatial extent of a typical radiofrequency ablated (RFA lesion in myocardial tissue, exhibiting significantly lower total depolarization at the necrotic core compared to healthy tissue, and intermediate values at the RFA rim region. Here, total depolarization in ablated myocardium was used to segment the total depolarization image into three (core, rim and healthy zones. A local fuzzy thresholding algorithm was used for this multi-region segmentation, and then compared with a ground truth segmentation obtained from manual demarcation of RFA core and rim regions on the histopathology image. Quantitative comparison of the algorithm segmentation results was performed with evaluation metrics such as dice similarity coefficient (DSC = 0.78 ± 0.02 and 0.80 ± 0.02, sensitivity (Sn = 0.83 ± 0.10 and 0.91 ± 0.08, specificity (Sp = 0.76 ± 0.17 and 0.72 ± 0.17 and accuracy (Acc = 0.81 ± 0.09 and 0.71 ± 0.10 for RFA core and rim regions, respectively. This automatic segmentation of parametric depolarization images suggests a novel application of optical polarimetry, namely its use in objective RFA image quantification.

  16. Ultrasound-guided percutaneous thermal ablation of hepatocellular carcinoma using microwave and radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Xu, H.-X.; Xie, X.-Y.; Lu, M.-D. E-mail: lumd@21cn.com; Chen, J.-W.; Yin, X.-Y.; Xu, Z.-F.; Liu, G.-J

    2004-01-01

    AIM: To investigate the therapeutic efficacy of thermal ablation for treatment of hepatocellular carcinoma (HCC) using microwave and radiofrequency (RF) energy application. MATERIALS AND METHODS: A total of 190 nodules in 97 patients (84 male, 13 female; mean age 53.4 years, range 24-74 years) with HCC were treated with microwave or RF ablation in the last 4 years. The applicators were introduced into the tumours under conscious analgesic sedation by intravenous administration of fentanyl citrate and droperidol and local anaesthesia in both thermal ablation procedures. The patients were then followed up with contrast-enhanced computed tomography (CT) to evaluate treatment response. Survival was analysed using the Kaplan-Meier method. RESULTS: Complete ablation was obtained in 92.6% (176/190) nodules. The complete ablation rates were 94.6% (106/112) in microwave ablation and 89.7% (70/78) in RF ablation. The complete ablation rates in tumours{<=}2.0, 2.1-3.9 and {>=}4.0 cm were 93.1, 93.8 and 86.4%, respectively. Local recurrence was found in 9.5% nodules and the rates in tumours{<=}2.0, 2.1-3.9 and {>=}4.0 cm in diameter were 3.4, 9.9 and 31.8%, respectively. In the follow-up period, 7.1% nodules ablated by microwave and 12.8% by RF presented local recurrence. The 1, 2 and 3-year distant recurrence-free survivals were 47.2, 34.9 and 31.0%, respectively. Estimated mean survival was 32 months, and 1, 2 and 3-year cumulative survivals were 75.6, 58.5, and 50.0%, respectively. One and 2 years survivals of Child-Pugh class A, B and C patients were 83.8 and 70.4%, 78.2 and 53.2%, 36.3 and 27.3%, respectively. CONCLUSION: Thermal ablation therapy by means of microwave and RF energy application is an effective and safe therapeutic technique for hepatocellular carcinoma. Large tumours can be completely ablated, but have a significantly higher risk of local recurrence at follow-up.

  17. Papillary thyroid carcinoma treated with radiofrequency ablation in a patient with hypertrophic cardiomyopathy: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jian Yi; Liu, Xiao Sun; Zhang, Qing; Hong, Yan Yun; Song, Bin; Teng, Xiao Dong; Yu, Ji Ren [The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou (China)

    2016-07-15

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jianyi; Liu, Xiaosun; Zhang, Qing; Hong, Yanyun; Song, Bin [Department of Gastrointestinal and Thyroid Surgery, The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou 310003 (China); Teng, Xiaodong [Department of Pathology, The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou 310003 (China); Yu, Jiren [Department of Gastrointestinal and Thyroid Surgery, The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou 310003 (China)

    2016-11-01

    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.

  19. Bleeding after percutaneous radiofrequency ablation: Successful treatment with transcatheter embolization

    Energy Technology Data Exchange (ETDEWEB)

    Carrafiello, Gianpaolo [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: gcarraf@tin.it; Lagana, Domenico [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: donlaga@gmail.com; Ianniello, Andrea [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: ianand@libero.it; Craparo, Giuseppe [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: crapgiu@libero.it; Recaldini, Chiara [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: chiarec@libero.it; Lumia, Domenico [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: domenicolumia@gmail.com; Dionigi, Gianlorenzo [Department of General Surgery, University of Insubria, 21100 Varese (Italy)]. E-mail: gianlorenzodionigi@uninsubria.it; Cuffari, Salvatore [Service of Anaesthesiology, University of Insubria, 21100 Varese (Italy)]. E-mail: domi7@libero.it; Fugazzola, Carlo [Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese (Italy)]. E-mail: radiovarese@libero.it

    2007-02-15

    Purpose: This knowledge will provide an ability to earlier detect bleeding complications after radiofrequency ablation (RFA), to manage these complications appropriately with endovascular procedures and minimize the sequelae. Materials and methods: From 2002 to 2005, 96 patients with 150 hepatic tumours underwent 126 RFA sessions. Fifty-eight patients had HCC, 34 had liver colorectal metastases and 4 had cholangiocellular carcinoma. Sixty-one patients were men and 35 were women (mean age 69.82 years, age range 39-89). The lesions number ranged from 1 to 7 per patients (mean 1.6 nodules) with a mean diameter of 28.5 mm (range 80-10 mm). Seventy-seven patients underwent a single ablative session, 13 patients underwent 2 sessions, 4 patients underwent 3 sessions and 2 patients underwent 4 sessions. The number of tumours treated in each ablative session was 1 in 106, 2 in 18 and 4 in 2 patients. Results: Two cases of serious haemorrhages occurred after the procedures in two patients treated for liver metastases. An endovascular embolization was proposed for both patients using polyvinyl-alcohol and micro-coils. The absence of bleeding was first confirmed during angiography and then by CT performed the day after the angiographic procedure. Conclusion: Transarterial embolization (TAE) represents the treatment of choice in the management of iatrogenic bleeding after RFA since it is minimally invasive, have a high success rate and a low incidence of complications compared to the more complex and dangerous surgical or laparoscopic options in patients who are often haemodynamically unstable and therefore at high anaesthetic and surgical risk.

  20. Radiofrequency catheter ablation: A study concerning electrode configuration, lesion size and potential complications

    Energy Technology Data Exchange (ETDEWEB)

    Anfinsen, Ole-Gunnar

    1999-07-01

    The study was performed to evaluate different methods of increasing the lesion size in radiofrequency catheter ablation, which is an important issue as the clinical indications for RF ablation are extended. The safety aspects of RF ablation are also studied, both with standard catheters and with experimental ones. The studies have been performed in vitro, in an animal model and in patients. The results are presented in 5 papers with titles of: 1) 'Radiofrequency catheter ablation of procine right atrium: Increased lesion size with bipolar two-catheter technique compared to unipolar application in vitro and in vivo. 2) Bipolar radiofrequency catheter ablation creates confluent lesions at a larger interelectrode spacing than does unipolar ablation from two electrodes in porcine heart. 3) Temperature-controlled radiofrequency catheter ablation with a 10 mm tip electrode creates larger lesions without charring in the porcine heart. 4) Radiofrequency catheter ablation in vitro: The difference between tissue and catheter tip temperature depends on location of the temperature sensor. 5) The activation of platelet function, coagulation and fibrinolysis during radiofrequency catheter ablation in heparin zed patients. The main conclusions are: 1) Large RF lesions may be created either by using larger electrodes and more power in the unipolar mode, or by changing the electrode configuration and thereby the geometry of the electrical field during RF current delivery. Both the 10 mm unipolar, the dielectrode and the bipolar mode showed feasible in porcine IVC-TV isthmus and right atrial free wall ablations, but the gain in lesion length was most pronounced in the bipolar mode. 2) Crater formation and intramural haemorrhages may complicate RF ablation using high current density in the right atrial free wall. In our study this was observed with 10 mm unipolar and bipolar two-catheter ablation. Phrenic nerve injury and lesions of the adjacent pulmonary tissue are risks

  1. Noninvasive radiofrequency ablation of cancer targeted by gold nanoparticles.

    Science.gov (United States)

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

    2008-08-01

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

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

    Science.gov (United States)

    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.

  3. Transthoracic percutaneous radiofrequency ablation for liver tumors in the hepatic dome.

    Science.gov (United States)

    Shibata, Toyomichi; Shibata, Toshiya; Maetani, Yoji; Kubo, Takeshi; Itoh, Kyo; Togashi, Kaori; Hiraoka, Masahiro

    2004-11-01

    Computed tomography (CT)-guided transthoracic radiofrequency ablation was performed for nine liver tumors of eight patients, which were located in the hepatic dome and undetectable by ultrasound (US). A total 11 sessions of ablation were performed. Complications were noted in five sessions (45%) and no complications were noted in six sessions (55%). Pneumothorax was noted in five sessions (45%), including two sessions (18%) with major pneumothorax requiring a chest tube. Major complications were seen in two sessions (18%), major pneumothorax and both major pneumothorax and moderate pleural effusion, respectively. CT-guided transthoracic radiofrequency ablation may be an alternative for treatments of liver tumor in the hepatic dome.

  4. Experimental and clinical studies with radiofrequency-induced thermal endometrial ablation for functional menorrhagia

    Energy Technology Data Exchange (ETDEWEB)

    Phipps, J.H.; Lewis, B.V.; Prior, M.V.; Roberts, T. (Watford General Hospital, Herts (England))

    1990-11-01

    A method of ablating the endometrium has been introduced into clinical practice that uses radiofrequency electromagnetic energy to heat the endometrium, using a probe inserted through the cervix. Preliminary studies suggest that over 80% of patients treated will develop either amenorrhea or a significant reduction in flow. The advantages of radiofrequency endometrial ablation over laser ablation or resection are the avoidance of intravascular fluid absorption, simplicity (no special operative hysteroscopic skills are required), speed of operation, and reduced cost compared with the Nd:YAG laser. In this paper, we describe the experimental studies performed during development of this new technique.

  5. Percutaneous treatment of bone tumors by radiofrequency thermal ablation

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Santiago, Fernando, E-mail: ferusan@ono.com [Department of Radiology, Hospital of Traumatology (Ciudad Sanitaria Virgen de las Nieves), Carretera de Jaen SN, 18013 Granada (Spain); Mar Castellano Garcia, Maria del; Guzman Alvarez, Luis [Department of Radiology, Hospital of Traumatology (Ciudad Sanitaria Virgen de las Nieves), Carretera de Jaen SN, 18013 Granada (Spain); Martinez Montes, Jose Luis [Department of Traumatology, Hospital of Traumatology (Ciudad Sanitaria Virgen de las Nieves), Carretera de Jaen SN, 18013 Granada (Spain); Ruiz Garcia, Manuel; Tristan Fernandez, Juan MIguel [Department of Radiology, Hospital of Traumatology (Ciudad Sanitaria Virgen de las Nieves), Carretera de Jaen SN, 18013 Granada (Spain)

    2011-01-15

    We present our experience of the treatment of bone tumors with radiofrequency thermal ablation (RFTA). Over the past 4 years, we have treated 26 cases (22 benign and 4 malignant) using CT-guided RFTA. RFTA was the sole treatment in 19 cases and was combined with percutaneous cementation during the same session in the remaining seven cases. Our approach to the tumors was simplified, using a single point of entrance for both RFTA and percutaneous osteoplasty. In the benign cases, clinical success was defined as resolution of pain within 1 month of the procedure and no recurrence during the follow-up period. It was achieved in 19 out of the 21 patients in which curative treatment was attempted. The two non-resolved cases were a patient with osteoid osteoma who developed a symptomatic bone infarct after a symptom-free period of 2 months and another with femoral diaphysis osteoblastoma who suffered a pathological fracture after 8 months without symptoms. The procedure was considered clinically successful in the five cases (4 malign and 1 benign) in which palliative treatment was attempted, because there was a mean ({+-}SD) reduction in visual analogue scale (VAS) pain score from 9.0 {+-} 0.4 before the procedure to <4 during the follow-up period.

  6. Thermal modeling of lesion growth with radiofrequency ablation devices

    Directory of Open Access Journals (Sweden)

    Nguyen Uyen D

    2004-08-01

    Full Text Available Abstract Background Temperature is a frequently used parameter to describe the predicted size of lesions computed by computational models. In many cases, however, temperature correlates poorly with lesion size. Although many studies have been conducted to characterize the relationship between time-temperature exposure of tissue heating to cell damage, to date these relationships have not been employed in a finite element model. Methods We present an axisymmetric two-dimensional finite element model that calculates cell damage in tissues and compare lesion sizes using common tissue damage and iso-temperature contour definitions. The model accounts for both temperature-dependent changes in the electrical conductivity of tissue as well as tissue damage-dependent changes in local tissue perfusion. The data is validated using excised porcine liver tissues. Results The data demonstrate the size of thermal lesions is grossly overestimated when calculated using traditional temperature isocontours of 42°C and 47°C. The computational model results predicted lesion dimensions that were within 5% of the experimental measurements. Conclusion When modeling radiofrequency ablation problems, temperature isotherms may not be representative of actual tissue damage patterns.

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

    Science.gov (United States)

    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. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

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    Chiara Dobrinja

    2015-01-01

    Full Text Available 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.

  9. Biophysics and clinical utility of irrigated-tip radiofrequency catheter ablation.

    Science.gov (United States)

    Houmsse, Mahmoud; Daoud, Emile G

    2012-01-01

    Catheter ablation by radiofrequency (RF) energy has successfully eliminated cardiac tachyarrhythmias. RF ablation lesions are created by thermal energy. Electrode catheters with 4-mm-tips have been adequate to ablate arrhythmias located near the endocardium; however, the 4-mm-tip electrode does not readily ablate deeper tachyarrhythmia substrate. With 8- and 10-mm-tip RF electrodes, ablation lesions were larger; yet, these catheters are associated with increased risk for coagulum, char and thrombus formation, as well as myocardial steam rupture. Cooled-tip catheter technology was designed to cool the electrode tip, prevent excessive temperatures at the electrode tip-tissue interface, and thus allow continued delivery of RF current into the surrounding tissue. This ablation system creates larger and deeper ablation lesions and minimizes steam pops and thrombus formation. The purpose of this article is to review cooled-tip RF ablation biophysics and outcomes of clinical studies as well as to discuss future technological improvements.

  10. Tissue temperatures and lesion size during irrigated tip catheter radiofrequency ablation

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, Adrian

    2000-01-01

    The limited success rate of radiofrequency catheter ablation in patients with ventricular tachycardias related to structural heart disease may be increased by enlarging the lesion size. Irrigated tip catheter ablation is a new method for enlarging the size of the lesion. It was introduced...... with standard temperature-controlled ablation at 70 degrees C and power-controlled irrigated tip ablation at 40 W, and infusion of 20 mL/min. Lesion size and tissue temperatures were significantly higher during all modes of irrigated tip ablation compared with standard temperature-controlled ablation (P ....05). Lesion volume correlated positively with tissue temperature (r = 0.87). The maximum recorded tissue temperature was always 1 mm from the ablation electrode and was 67 +/- 4 degrees C for standard ablation and 93 +/- 6 degrees C, 99 +/- 6 degrees C, and 115 +/- 13 degrees C for temperature...

  11. Surgical Radiofrequency MAZE III Ablation for Treatment of Atrial Fibrillation During Open Heart Surgery

    Directory of Open Access Journals (Sweden)

    Fariborz Akbarzadeh

    2006-05-01

    Full Text Available Background: Atrial fibrillation is a common arrhythmia in patients with rheumatic mitral and other valve diseases who are candidates for valve repair surgeries. Conversion of rhythm to sinus has positive effects on quality of life and lower use of medications. The aim of this clinical study was to evaluate the effectiveness of the radiofrequency ablation Maze III procedure in the treatment of atrial fibrillation associated with rheumatic heart valve disease. Methods: We applied a modified Cox III Maze procedure using radiofrequency ablation in the treatment of atrial fibrillation associated with rheumatic heart valve disease and evaluated the outcome of 20 patients of atrial fibrillation associated rheumatic valve disease who underwent radiofrequency ablation Maze III procedure plus heart valve surgery. Demographic, echocardiographic, Electrocardiographic and Doppler study data were calculated before surgery, six month and one year after surgery.. Results: No perioperative deaths occurred in the study group. Duration of additional time for doing radiofrequency ablation was about 22 minutes. Freedom from atrial fibrillation was 85% and 75% at six months and one year follow-up respectively... Conclusions: The addition of the radiofrequency ablation Maze procedure to heart valve surgery is safe and effective in the treatment of atrial fibrillation associated with rheumatic heart valve disease.

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

    Science.gov (United States)

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

    2014-04-01

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

  13. Liquid metal bath as conformable soft electrodes for target tissue ablation in radio-frequency ablation therapy.

    Science.gov (United States)

    Sun, Xuyang; He, Zhi-Zhu; Deng, Zhong-Shan; Zhou, Yi-Xin; Liu, Jing

    2017-11-23

    Radio-frequency ablation has been an important physical method for tumor hyperthermia therapy. The conventional rigid electrode boards are often uncomfortable and inconvenient for performing surgery on irregular tumors, especially for those tumors near the joints, such as ankles, knee-joints or other facets like finger joints. We proposed and demonstrated a highly conformable tumor ablation strategy through introducing liquid metal bath as conformable soft electrodes. Different heights of liquid metal bath electrodes were adopted to perform radio-frequency ablation on targeted tissues. Temperature and ablation area were measured to compare the ablation effect with plate metal electrodes. The recorded temperature around the ablation electrode was almost twice as high as that with the plate electrode and the effective ablated area was 2-3 fold larger in all the mimicking situations of bone tumors, span-shaped or round-shaped tumors. Another unique feature of the liquid metal electrode therapy is that the incidence of heat injury was reduced, which is a severe accident that can occur during the treatment of irregular tumors with plate metal boards. The present method suggests a new way of using soft liquid metal bath electrodes for targeted minimally invasive tumor ablation in future clinical practice.

  14. Thermal Ablation of Colorectal Lung Metastases: Retrospective Comparison Among Laser-Induced Thermotherapy, Radiofrequency Ablation, and Microwave Ablation.

    Science.gov (United States)

    Vogl, Thomas J; Eckert, Romina; Naguib, Nagy N N; Beeres, Martin; Gruber-Rouh, Tatjana; Nour-Eldin, Nour-Eldin A

    2016-12-01

    The purpose of this study is to retrospectively evaluate local tumor control, time to tumor progression, and survival rates among patients with lung metastatic colorectal cancer who have undergone ablation therapy performed using laser-induced thermotherapy (LITT), radiofrequency ablation (RFA), or microwave ablation (MWA). Data for this retrospective study were collected from 231 CT-guided ablation sessions performed for 109 patients (71 men and 38 women; mean [± SD] age, 68.6 ± 11.2 years; range, 34-94 years) from May 2000 to May 2014. Twenty-one patients underwent LITT (31 ablations), 41 patients underwent RFA (75 ablations), and 47 patients underwent MWA (125 ablations). CT scans were acquired 24 hours after each therapy session and at follow-up visits occurring at 3, 6, 12, 18, and 24 months after ablation. Survival rates were calculated from the time of the first ablation session, with the use of Kaplan-Meier and log-rank tests. Changes in the volume of the ablated lesions were measured using the Kruskal-Wallis method. Local tumor control was achieved in 17 of 25 lesions (68.0%) treated with LITT, 45 of 65 lesions (69.2%) treated with RFA, and 91 of 103 lesions (88.3%) treated with MWA. Statistically significant differences were noted when MWA was compared with LITT at 18 months after ablation (p = 0.01) and when MWA was compared with RFA at 6 months (p = 0.004) and 18 months (p = 0.01) after ablation. The overall median time to local tumor progression was 7.6 months. The median time to local tumor progression was 10.4 months for lesions treated with LITT, 7.2 months for lesions treated with RFA, and 7.5 months for lesions treated with MWA, with no statistically significant difference noted. New pulmonary metastases developed in 47.6% of patients treated with LITT, in 51.2% of patients treated with RFA, and in 53.2% of patients treated with MWA. According to the Kaplan-Meier test, median survival was 22.1 months for patients who underwent LITT, 24.2 months

  15. Indication of the radiofrequency induced lesion size by pre-ablation measurements

    DEFF Research Database (Denmark)

    Stagegaard, Niels; Petersen, Helen Høgh; Chen, Xu

    2005-01-01

    BACKGROUND: During radiofrequency ablation of arrhythmias tissue heating and hence lesion size depend on electrode-tissue contact and cooling of the electrode tip caused by cavitary blood flow. These factors are unique and unknown for each catheter placement in the beating heart. A tool for asses......BACKGROUND: During radiofrequency ablation of arrhythmias tissue heating and hence lesion size depend on electrode-tissue contact and cooling of the electrode tip caused by cavitary blood flow. These factors are unique and unknown for each catheter placement in the beating heart. A tool...... for assessing these factors prior to ablation may indicate the lesion size which will be obtained for any given catheter position. METHODS AND RESULTS: Radiofrequency ablation was performed in vitro on strips of left ventricular porcine myocardium during two different levels of convective cooling (0 or 0.1 m......, during unchanged conditions, radiofrequency ablation was performed as either temperature-controlled, power-controlled or irrigated tip ablation and lesion size was determined. DeltaIMP increased significantly (P

  16. Radiofrequency ablation with epinephrine injection: in vivo study in normal pig livers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Jung; Lee, Dong Hoo; Lim, Joo Won; Ko, Young Tae; Kim, Youn Wha; Choi, Bong Keun [Kyung Hee University Medical Center, Seoul (Korea, Republic of)

    2007-07-15

    We wanted to evaluate whether epinephrine injection prior to radiofrequency (RF) ablation can increase the extent of thermally mediated coagulation in vivo normal pig liver tissue. Eighteen RF ablation zones were created in six pigs using a 17-gauge internally cooled electrode under ultrasound guidance. Three RF ablation zones were created in each pig under three conditions: RF ablation alone, RF ablation after the injection of 3 mL of normal saline, and RF ablation after the injection of 3 mL of epinephrine (1:10,000 solution). After the RF ablation, we measured the short and long diameters of the white zones in the gross specimens. Three of the RF ablations were technically unsuccessful; therefore, measurement of white zone was finally done in 15 RF ablation zones. The mean short and long diameters of the white zone of the RF ablation after epinephrine injection (17.2 mm {+-} 1.8 and 20.8 mm {+-} 3.7, respectively) were larger than those of RF ablation only (10 mm {+-} 1.2 and 12.2 mm {+-} 1.1, respectively) and RF ablation after normal saline injection (12.8 mm {+-} 1.5 and 15.6 mm {+-} 2.5, respectively) ({rho} < .05). RF ablation with epinephrine injection can increase the diameter of the RF ablation zone in normal pig liver tissue.

  17. Percutaneous Ultrasound-guided Radiofrequency Ablation of Intrahepatic Cholangiocarcinoma

    Directory of Open Access Journals (Sweden)

    Yi-You Chiou

    2005-07-01

    Full Text Available This study evaluated the clinical applications, treatment effects, and complications of percutaneous ultrasound (US-guided radiofrequency ablation (RFA of intrahepatic cholangiocarcinoma. Ten patients (6 men and 4 women with histologically proven cholangiocarcinoma underwent US-guided percutaneous RFA. Tumor diameters ranged from 1.9 to 6.8 cm. There were 12 sessions of RFA for 10 solitary cholangiocarcinomas. Eight patients were treated at a single session and two patients had two treatment sessions. The efficacy of RFA was evaluated using contrast-enhanced dynamic computed tomography 1 month after treatment and then every 3 months. Complete necrosis was defined as lack of contrast enhancement of the treated region. There was complete necrosis in eight tumors. In two patients with large tumors (4.7 and 6.8 cm in diameter, enhancement of residual tissue was observed after RFA treatment, indicating residual tumor. Complete necrosis was seen in all five tumors (100% with diameters of 3.0 cm or less, two of three tumors (67% with diameters of 3.1-5.0 cm, and one of two tumors (50% with diameters of more than 5.0 cm. A large biloma was found in one patient after treatment. No serious complications occurred in the other nine patients. In conclusion, percutaneous RFA is effective and successful in the treatment of intrahepatic cholangiocarcinoma of 3 cm or less and satisfactory for tumors of 3-5 cm. The rate of serious complications after RFA is low. Further follow-up is necessary to determine long-term efficacy.

  18. Anatomical Comparison of Radiofrequency Ablation Techniques for Sacroiliac Joint Pain.

    Science.gov (United States)

    Roberts, Shannon L; Stout, Alison; Loh, Eldon Y; Swain, Nathan; Dreyfuss, Paul; Agur, Anne M

    2018-02-05

    To compare the percentage of sacral lateral branches (LBs) that would be captured if lesions were created by seven current sacroiliac joint (SIJ) radiofrequency ablation (RFA) techniques: three monopolar and four bipolar. Cadaveric fluoroscopy study. Anatomy and surgical skills laboratories. Forty cadaveric SIJs. LBs were exposed, radiopaque wires were sutured to LBs, and anterior-posterior fluoroscopic images through the S1 superior endplate were obtained. Lesions that would be created by 17 versions of seven current SIJ RFA techniques were mapped on the fluoroscopic images. These 17 versions were compared: 1) percentage of LBs that would be captured; 2) percentage of SIJ specimens in which 100% of LBs would be captured; and 3) percentage of LBs that would not be captured at each level (S1-S4). Both the mean LB and 100% capture rates were greater for the bipolar techniques (93.4-99.7% and 62.5-97.5%, respectively) than for the monopolar techniques (49.6-99.1% and 2.5-92.5%, respectively) evaluated. For the bipolar techniques, 1.5-29.2% of LBs would not be captured at S1 and 0% at S2-S4 vs 0-29.2% at S1-S4 for the cooled monopolar techniques vs 36.9-100% at S1-S4 for the conventional monopolar technique. The findings suggest that, if lesions were created, the RFA needle placement locations of the bipolar techniques evaluated may be capable of capturing all LBs, but those of the current monopolar techniques evaluated may not. Future in vivo imaging studies are required to compare the lesion morphology generated by different SIJ RFA techniques and correlate the findings with clinical outcomes.

  19. Temperature-controlled irrigated tip radiofrequency catheter ablation

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, Adrian

    1998-01-01

    INTRODUCTION: In patients with ventricular tachycardias due to structural heart disease, catheter ablation cures ... AND RESULTS: In vivo anesthetized pigs were ablated in the left ventricle. In vitro strips of porcine left ventricular myocardium were ablated in a tissue bath. Lesion volume was significantly larger after irrigated tip ablation both in vivo (544 +/- 218 vs 325 +/- 194 mm3, P

  20. Bilateral occipital lobe infarction with altitudinal field loss following radiofrequency cardiac catheter ablation

    Directory of Open Access Journals (Sweden)

    Chen Celia S

    2010-03-01

    Full Text Available Abstract Background Bilateral stroke following radiofrequency catheter ablation is an unusual complication and may result in bilateral altitudinal visual field defects. Bilateral altitudinal visual field defects usually result from prechiasmal pathology causing damage to both retinas or optic nerves and rarely from bilateral symmetric damage to the post chiasmal visual pathways. Case presentation A 48-year-old man complained of visual disturbance on wakening following radiofrequency catheter ablation. The patient had a CHADS score of 1 pre-operatively and no complications were noted intra-operatively. Examination revealed a bilateral superior altitudinal defect and MRI of the brain showed multifocal areas of infarction predominantly involving the occipital lobes which correlated to with the visual deficits. Conclusion While the risk of thromboembolism and perioperative stroke during radiofrequency catheter ablation is small, it is not insignificant.

  1. Combination therapy of temporary tracheal stenting and radiofrequency ablation for multinodular thyroid goiter with airway compression

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji Hoon; Beak, Jung Hwan; Oh, Yeon Mok; Ha, Eun Ju; Lee, Jeong Hyun [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2013-10-15

    We report a case of multinodular thyroid goiter in an 80-year-old man who successfully underwent tracheal stent placement for respiratory distress caused by the thyroid goiter and following two radiofrequency (RF) ablation sessions performed for thyroid volume reduction. This sequential treatment allowed elective stent removals four weeks after the second RF ablation session because the thyroid volume had been progressively reduced. Combination therapy of temporary airway stenting and RF ablation for the treatment of thyroid goiter has two advantages, i.e., immediate reliefs of dyspnea with airway stenting and reductions of the thyroid volume with RF ablation, and thus, allowing symptom reliefs even after the stent removals.

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

    Science.gov (United States)

    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.

  3. Efficacy and survival analysis of percutaneous radiofrequency versus microwave ablation for hepatocellular carcinoma: an Egyptian multidisciplinary clinic experience.

    Science.gov (United States)

    Abdelaziz, Ashraf; Elbaz, Tamer; Shousha, Hend Ibrahim; Mahmoud, Sherif; Ibrahim, Mostafa; Abdelmaksoud, Ahmed; Nabeel, Mohamed

    2014-12-01

    Hepatocellular carcinoma (HCC) is a primary tumor of the liver with poor prognosis. For early stage HCC, treatment options include surgical resection, liver transplantation, and percutaneous ablation. Percutaneous ablative techniques (radiofrequency and microwave techniques) emerged as best therapeutic options for nonsurgical patients. We aimed to determine the safety and efficacy of radiofrequency and microwave procedures for ablation of early stage HCC lesions and prospectively follow up our patients for survival analysis. One Hundred and 11 patients with early HCC are managed in our multidisciplinary clinic using either radiofrequency or microwave ablation. Patients are assessed for efficacy and safety. Complete ablation rate, local recurrence, and overall survival analysis are compared between both procedures. Radiofrequency ablation group (n = 45) and microwave ablation group (n = 66) were nearly comparable as regards the tumor and patients characteristics. Complete ablation was achieved in 94.2 and 96.1% of patients managed by radiofrequency and microwave ablation techniques, respectively (p value 0.6) with a low rate of minor complications (11.1 and 3.2, respectively) including subcapsular hematoma, thigh burn, abdominal wall skin burn, and pleural effusion. Ablation rates did not differ between ablated lesions ≤ 3 and 3-5 cm. A lower incidence of local recurrence was observed in microwave group (3.9 vs. 13.5% in radiofrequency group, p value 0.04). No difference between both groups as regards de novo lesions, portal vein thrombosis, and abdominal lymphadenopathy. The overall actuarial probability of survival was 91.6% at 1 year and 86.1% at 2 years with a higher survival rates noticed in microwave group but still without significant difference (p value 0.49). Radiofrequency and microwave ablations led to safe and equivalent ablation and survival rates (with superiority for microwave ablation as regards the incidence of local recurrence).

  4. Effect of Change in Portal Vein Flow Rates on Hepatic Ablations Created with a Bipolar Radiofrequency Ablation Device.

    Science.gov (United States)

    Dodd, Gerald D; Lanctot, Anthony C; Lind, Kimberly E

    2017-05-01

    Purpose To investigate the effect of change in portal vein flow rates on the size and shape of ablations created by a bipolar radiofrequency (RF) ablation device. Materials and Methods This study was exempt from institutional animal care and use committee review. An in vitro bovine liver model perfused with autologous blood via the portal vein at three flow rates (60, 80, 100 mL/min per 100 g of liver) was used. Four ablations, two bipolar and two monopolar (control probe), were made in each of five livers perfused at each flow rate. Short- and long-axis diameters were measured from gross specimens, and volume and sphericity index were calculated for each ablation. A general linear mixed model accounting for correlation within the liver was used to evaluate the effects of flow on ablations. Analyses were performed by using software. Results There was no significant difference in the size or shape of ablations created by the bipolar device at the different flow rates (P > .05 for all outcomes). The monopolar device demonstrated the expected inverse association between ablation size and change in flow (P flow rates does not have a statistically significant effect on the size or shape of ablations created by the bipolar RF ablation device tested. (©) RSNA, 2016.

  5. Right atrial mass following transcatheter radiofrequency ablation for recurrent atrial fibrillation: thrombus, endocarditis or mixoma?

    Science.gov (United States)

    Ancona, Roberta; Comenale Pinto, Salvatore; Caso, Pio; Di Palma, Vito; Pisacane, Francesca; Martiniello, Alfonso Roberto; Quarto, Cesare; De Rosa, Nicla; Pisacane, Carlo; Calabrò, Raffaele

    2009-03-01

    We report a case of an asymptomatic patient in whom a right atrial mass was fortuitously documented by echocardiography few months after a transcatheter radiofrequency catheter ablation for recurrent AF. No masses were seen in the cardiac chambers before the ablative procedure, raising important diagnostic and decision-making issues. The patient was referred to the surgeon and a diagnosis of right atrial myxoma was made.

  6. Treatment of Osteoid Osteomas Using a Navigational Bipolar Radiofrequency Ablation System

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, Adam N., E-mail: wallacea@mir.wustl.edu; Tomasian, Anderanik, E-mail: tomasiana@mir.wustl.edu [Washington University School of Medicine, Mallinckrodt Institute of Radiology (United States); Chang, Randy O., E-mail: changr@wusm.wustl.edu [Washington University School of Medicine (United States); Jennings, Jack W., E-mail: jenningsj@mir.wustl.edu [Washington University School of Medicine, Mallinckrodt Institute of Radiology (United States)

    2016-05-15

    BackgroundPercutaneous CT-guided radiofrequency ablation is a safe and effective minimally invasive treatment for osteoid osteomas. This technical case series describes the use of a recently introduced ablation system with a probe that can be curved in multiple directions, embedded thermocouples for real-time monitoring of the ablation volume, and a bipolar design that obviates the need for a grounding pad.MethodsMedical records of all patients who underwent radiofrequency ablation of an osteoid osteoma with the STAR Tumor Ablation System (DFINE; San Jose, CA) were reviewed. The location of each osteoid osteoma, nidus volume, and procedural details were recorded. Treatment efficacy and long-term complications were assessed at clinical follow-up.ResultsDuring the study period, 18 osteoid osteomas were radiofrequency ablated with the multidirectional bipolar system. Lesion locations included the femur (50 %; 9/18), tibia (22 %; 4/18), cervical spine (11 %; 2/18), calcaneus (5.5 %; 1/18), iliac bone (5.5 %; 1/18), and fibula (5.5 %; 1/18). The median nidus volume of these cases was 0.33 mL (range 0.12–2.0 mL). All tumors were accessed via a single osseous channel. Median cumulative ablation time was 5 min and 0 s (range 1 min and 32 s–8 min and 50 s). All patients with clinical follow-up reported complete symptom resolution. No complications occurred.ConclusionSafe and effective CT-guided radiofrequency ablation of osteoid osteomas can be performed in a variety of locations using a multidirectional bipolar system.

  7. Heat sink phenomenon of bipolar and monopolar radiofrequency ablation observed using polypropylene tubes for vessel simulation.

    Science.gov (United States)

    Al-Alem, Ihssan; Pillai, Krishna; Akhter, Javed; Chua, Terence C; Morris, David L

    2014-06-01

    Radiofrequency ablation (RFA) is widely used for treating liver tumors; recurrence is common owing to proximity to blood vessels possibly due to the heat sink effect. We seek to investigate this phenomenon using unipolar and bipolar RFA on an egg white tumor tissue model and an animal liver model. Temperature profiles during ablation (with and without vessel simulation) were studied, using both bipolar and unipolar RFA probes by 4 strategically placed temperature leads to monitor temperature profile during ablation. The volume of ablated tissue was also measured. The volume ablated during vessel simulation confirmed the impact of the heat sink phenomenon. The heat sink effect of unipolar RFA was greater compared with bipolar RFA (ratio of volume affected 2:1) in both tissue and liver models. The volume ablated using unipolar RFA was less than the bipolar RFA (ratio of volume ablated = 1:4). Unipolar RFA achieved higher ablation temperatures (122°C vs 98°C). Unipolar RFA resulted in tissue damage beyond the vessel, which was not observed using bipolar RFA. Bipolar RFA ablates a larger tumor volume compared with unipolar RFA, with a single ablation. The impact of heat sink phenomenon in tumor ablation is less so with bipolar than unipolar RFA with sparing of adjacent vessel damage. © The Author(s) 2013.

  8. Outcomes after resection and/or radiofrequency ablation for recurrence after treatment of colorectal liver metastases

    NARCIS (Netherlands)

    Hof, J.; Wertenbroek, M. W. J. L. A. E.; Peeters, P. M. J. G.; Widder, J.; Sieders, E.; de Jong, K. P.

    Background: Repeat liver resection for colorectal liver metastases (CRLMs) is possible in a limited number of patients, with radiofrequency ablation (RFA) as an alternative for unresectable CRLMs. The aim of this study was to analyse survival rates with these interventions. Methods: This was a

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

    NARCIS (Netherlands)

    Boone, Judith; Bex, Axel; Prevoo, Warner

    2012-01-01

    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

  10. Multipolar radiofrequency ablation for colorectal liver metastases close to major hepatic vessels

    NARCIS (Netherlands)

    Snoeren, Nikol; Nijkamp, Maarten W.; Berendsen, Tim; Govaert, Klaas M.; van Kessel, Charlotte S.; Borel Rinkes, Inne H M; Van Hillegersberg, Richard

    2015-01-01

    Background: Resection of colorectal liver metastases (CRLM) is often hindered by their location close to the major hepatic vessels. So far, radiofrequency ablation for perivascular tumours was thought to be ineffective and unsafe due to either the heat sink effect or vascular thrombosis. The aim of

  11. Increased resting heart rate following radiofrequency catheter ablation for atrial fibrillation

    DEFF Research Database (Denmark)

    Nilsson, Brian; Chen, Xu; Pehrson, Steen

    2005-01-01

    AIM: Sinus tachycardia has been observed following radiofrequency (RF) catheter ablation for various kinds of supraventricular tachycardia. This study is aimed at determining the occurrence of changes in sinus-rhythm heart rate (HR) after pulmonary vein (PV) isolation in patients with paroxysmal...

  12. Hip fracture after radiofrequency ablation therapy for bone tumors : two case reports

    NARCIS (Netherlands)

    Dierselhuis, Edwin F.; Jutte, Paul C.; van der Eerden, Pepijn J. M.; Suurmeijer, Albert J. H.; Bulstra, Sjoerd K.

    2010-01-01

    Radiofrequency ablation (RFA) has become a valuable therapeutic modality in cancer treatment over the last decade. In orthopedic surgery, RFA is used for the treatment of benign bone tumors and bone metastases. Complications are rare and, to our knowledge, bone fracture as a complication due solely

  13. Assessment of ablative margin by MRI with ferucarbotran in radiofrequency ablation for liver cancer: comparison with enhanced CT.

    Science.gov (United States)

    Tokunaga, S; Koda, M; Matono, T; Sugihara, T; Nagahara, T; Ueki, M; Murawaki, Y; Kakite, S; Yamashita, E

    2012-06-01

    Our aim was to determine whether ablated liver parenchyma surrounding a tumour can be assessed by MRI with ferucarbotran administered prior to radiofrequency ablation (RFA) compared with enhanced CT. 55 hepatocellular carcinomas (HCCs) in 42 patients and 5 metastatic liver cancers in 3 patients were treated by RFA after ferucarbotran administration. We then performed T(2)* weighted MRI after 1 week and enhanced CT after 1 month. T(2)* weighted MRI demonstrated the ablated parenchyma as a low-intensity rim around the high intensity of the ablated tumour in these cases. The assessment was allocated to one of three grades: margin (+), high-intensity area with continuous low-intensity rim; margin zero, high-intensity area with discontinuous low-intensity rim; and margin (-), high-intensity area extending beyond the low-intensity rim. Margin (+), margin zero and margin (-) were found in 17, 35 and 5 nodules, respectively. All 17 nodules with margin (+) and 13 of those with margin zero were assessed as having sufficient ablative margins on CT. The remaining 22 nodules with margin zero had insufficient margins on CT. The overall agreement between MRI and CT for the diagnosis of the ablative margin was moderate (κ = 0.507, p ablative margin to be visualised as a low-intensity rim, and also enables the evaluation of the ablative margin to be made earlier and more easily than with enhanced CT.

  14. Histopathology of breast cancer after magnetic resonance-guided high-intensity focused ultrasound and radiofrequency ablation

    NARCIS (Netherlands)

    Knuttel, Floor; Waaijer, Laurien; Merckel, LG; van den Bosch, Maurice A A J; Witkamp, Arjen J.; Deckers, Roel; van Diest, Paul J.

    AIMS: Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation and radiofrequency ablation (RFA) are being researched as possible substitutes for surgery in breast cancer patients. The histopathological appearance of ablated tissue has not been studied in great detail. This

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

    Science.gov (United States)

    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

  16. Tissue temperatures and lesion size during irrigated tip catheter radiofrequency ablation: an in vitro comparison of temperature-controlled irrigated tip ablation, power-controlled irrigated tip ablation, and standard temperature-controlled ablation

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, A

    2000-01-01

    The limited success rate of radiofrequency catheter ablation in patients with ventricular tachycardias related to structural heart disease may be increased by enlarging the lesion size. Irrigated tip catheter ablation is a new method for enlarging the size of the lesion. It was introduced...... temperature-controlled ablation and power-controlled irrigated tip ablation. In vitro strips of porcine left ventricular myocardium were ablated. Temperature-controlled irrigated tip ablation at target temperatures 60 degrees C, 70 degrees C, and 80 degrees C with infusion of 1 mL saline/min were compared...

  17. Outcomes of Radiofrequency Ablation for Dysplastic Barrett’s Esophagus: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Carmelo Luigiano

    2016-01-01

    Full Text Available Barrett’s esophagus is a condition in which the normal squamous lining of the esophagus has been replaced by columnar epithelium containing intestinal metaplasia induced by recurrent mucosal injury related to gastroesophageal reflux disease. Barrett’s esophagus is a premalignant condition that can progress through a dysplasia-carcinoma sequence to esophageal adenocarcinoma. Multiple endoscopic ablative techniques have been developed with the goal of eradicating Barrett’s esophagus and preventing neoplastic progression to esophageal adenocarcinoma. For patients with high-grade dysplasia or intramucosal neoplasia, radiofrequency ablation with or without endoscopic resection for visible lesions is currently the most effective and safe treatment available. Recent data demonstrate that, in patients with Barrett’s esophagus and low-grade dysplasia confirmed by a second pathologist, ablative therapy results in a statistically significant reduction in progression to high-grade dysplasia and esophageal adenocarcinoma. Treatment of dysplastic Barrett’s esophagus with radiofrequency ablation results in complete eradication of both dysplasia and of intestinal metaplasia in a high proportion of patients with a low incidence of adverse events. A high proportion of treated patients maintain the neosquamous epithelium after successful treatment without recurrence of intestinal metaplasia. Following successful endoscopic treatment, endoscopic surveillance should be continued to detect any recurrent intestinal metaplasia and/or dysplasia. This paper reviews all relevant publications on the endoscopic management of Barrett’s esophagus using radiofrequency ablation.

  18. The effect of radiofrequency ablation on different organs: Ex vivo and in vivo comparative studies

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoo Na [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Rhim, Hyunchul, E-mail: rhimhc@skku.edu [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Choi, Dongil; Kim, Young-sun; Lee, Min Woo; Chang, Ilsoo; Lee, Won Jae; Lim, Hyo K. [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of)

    2011-11-15

    Objective: The purposes of this study are to evaluate the ex vivo and in vivo efficacy of radiofrequency ablation (RFA) on different porcine tissues by the ablation of three different sites simultaneously. Materials and methods: A multichannel RFA system, enables three separate tumors to be ablated simultaneously, was used. RFA procedures were applied to normal porcine liver, kidney, and muscle together ex vivo (n = 12) and in vivo (n = 17). Pre-impedances, defined as baseline systemic impedances of tissues before beginning RFA, and the areas of ablation zones were measured and compared. Results: The areas of ablation zones among three organs had a significant difference in decreasing order as follows: liver, muscle, and kidney in the ex vivo study (p = 0.001); muscle, liver, and kidney in the in vivo study (p < 0.0001). The areas of ablation zones between ex vivo and in vivo had a significant difference in the liver and muscle (each p < 0.05). There was no significant correlation between the areas of ablation zones and pre-impedances in both studies. Conclusions: Renal RFA produced the smallest ablation zone in both in vivo and ex vivo studies. Muscular RFA demonstrated the largest ablation zone in the in vivo study, and hepatic RFA showed the largest ablation zone in the ex vivo study. This variability in the tissues should be considered for performing an optimized RFA for each organ site.

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

    DEFF Research Database (Denmark)

    Weber, Britta; Liu, Mitchell; Sobkin, Paul

    2016-01-01

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

  20. Interactive In-Vitro Training In Physics Of Radiofrequency Ablation For Physicians And Medical Engineering Students.

    Science.gov (United States)

    Haber, T; Kleister, G; Selman, B; Härtig, J; Melichercik, J; Ismer, B

    2016-01-01

    Radiofrequency (RF) ablation requires a complex set of devices as well as profound electrophysiological experience and substantial knowledge of physical science basics. To establish RF ablation in-vitro teaching-system, six workstations were equipped with computer-controlled RF ablation generators. Universal connection boxes allow ablation-essays with catheters of different make and model. Special wetlabs were developed combining a basin containing isotonic saline solution with a thermostat and a pump to simulate blood flow. This hands-on teaching system can be used to demonstrate differences in lesion-forming dependent on tip-electrodes, sensor technology and ablation techniques, influence of blood flow and electrode-angle to the myocardium. It was also utilized to reproduce industrial in-vitro tests.

  1. Clinical evaluation of a novel bipolar radiofrequency ablation system for renal masses.

    Science.gov (United States)

    Okhunov, Zhamshid; Roy, Ornob; Duty, Brian; Waingankar, Nikhil; Herati, Amin; Morgenstern, Nora; Sheikh-Fayyaz, Silvat; Kavoussi, Louis R

    2012-09-01

    What's known on the subject? and What does the study add? With the advancement of minimally invasive surgery, the management of small renal masses (SRM) has dramatically changed. Ablative technology such as radiofrequency ablation (RFA) and cryoablation have emerged as viable alternative modalities to extirpative surgery. RFA is one of the most studied and applied energy-based, needle-ablative treatment modalities, with encouraging mid- and long-term oncological outcomes. Monopolar devices have several shortcomings. The electrodes are susceptible to the cooling effect of nearby blood vessels that act as a 'heat sink', limiting the extent of tissue ablation and forming lesions with asymmetric borders and 'skip lesions'. Therefore, it is difficult to monitor and accurately predict the size of ablated lesions. A novel bipolar radiofrequency ablation (BRFA) device has been recently developed to address concerns with monopolar systems (Trod Medical, Paris, France). The BRFA system addresses the limitations of monopolar RFA, in terms of lesion size, targeting, consistency and concerns about cell death in the ablated area. We evaluated the BRFA device in 10 patients undergoing laparoscopic partial or radical nephrectomy. The present study demonstrates the safety and efficacy of a novel BRFA device. A BRFA device can produce a defined reproducible lesion with a precise transition zone to normal tissue. The area of ablated tissue exhibited completely devitalized cells and precise transition zone. With these characteristics, the potential advantages of this new technology during RFA ablation of SRM include less collateral damage and more complete ablation without skip lesions. This has the potential to lower rates of local recurrence and reduce incidence of skin burns. Further follow-up studies are necessary to determine its oncological efficacy. To evaluate a novel bipolar radiofrequency ablation (BRFA) system for the destruction of kidney tumours in patients. Bipolar

  2. Insufficient ablative margin determined by early computed tomography may predict the recurrence of hepatocellular carcinoma after radiofrequency ablation.

    Science.gov (United States)

    Teng, Wei; Liu, Ka-Wai; Lin, Chen-Chun; Jeng, Wen-Juei; Chen, Wei-Ting; Sheen, I-Shyan; Lin, Chun-Yen; Lin, Shi-Ming

    2015-03-01

    Tumor recurrence in hepatocellular carcinoma (HCC) patients after radiofrequency ablation (RFA) remains common; some studies have reported that insufficient ablative margin after RFA might contribute to HCC recurrence. The aim of this study was to investigate whether insufficient ablative safety margins determined by early computed tomography (CT) predicts HCC recurrence after RFA. This retrospective study recruited patients with a single HCC lesion after RFA in our department between May 2013 and March 2014. Early follow-up CT was performed within 7 days after RFA. An adequate ablative margin assessed by follow-up CT was defined as (maximum post-RFA CT radius)(3)/(maximum pre-RFA CT radius + 5 mm)(3)> 1. All patients in whom complete ablation was achieved underwent a CT scan every 3 months for early detection of HCC recurrence. In total, 72 patients (48 male, mean age 69.4 years) were analyzed. Of these, eight patients had local tumor progression, four had intra-hepatic distant recurrence, and two had extra-hepatic metastasis. Insufficient ablative margin, defined as an ablative volume with a safety margin of less than 5 mm, was an important predictor of local tumor progression (LTP) (p = 0.015) and overall recurrence (p = 0.012). The sensitivity, specificity, and positive and negative predictive values of an insufficient ablative margin for predicting LTP and overall recurrence were 36.4%, 97.2%, 50.0%, and 87.9%, and 46.2%, 89.7%, 42.9%, and 87.9%, respectively. An ablative volume with an ablative margin of less than 5 mm is associated with higher rates of both LTP and overall recurrence in HCC after RFA.

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

    Science.gov (United States)

    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.

  4. Osteoid osteoma of the spine: CT-guided monopolar radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Martel, Jose [Departamento de Diagnostico por Imagen, Fundacion Hospital Alcorcon, Alcorcon, Madrid (Spain)], E-mail: jmartel@fhalcorcon.es; Bueno, Angel [Departamento de Diagnostico por Imagen, Fundacion Hospital Alcorcon, Alcorcon, Madrid (Spain); Nieto-Morales, M Luisa [Servicio de Radiologia, Hospital Universitario de Tenerife (Spain); Ortiz, Eduardo J. [Departamento de Cirugia Ortopedica, Fundacion Hospital Alcorcon, Alcorcon, Madrid (Spain)

    2009-09-15

    CT-guided percutaneous radiofrequency ablation and laser photocoagulation have become the methods of choice for the treatment of all osteoid osteomas except those in contact with neural structures. We report 10 patients with spinal osteoid osteoma adjacent to the neural elements treated with 12 sessions of CT-guided monopolar radiofrequency ablation. The size range of the lesion was 3-14 mm (mean, 7.5 mm) and the distance between the nidus and the adjacent spinal cord or nerve root was 2-12 mm (mean, 5 mm). No intact cortex between the tumor and the spinal cord or nerve roots constituted an exclusion criterion because of a higher risk of undesirable neurotoxic effects. Patients were under general anesthesia. After location of the lesion, a 11G-bone biopsy was introduced into the nidus. The radiofrequency electrode was inserted through the biopsy needle and heated at 90 deg. C for 4 min. Primary success was obtained in eight patients. At follow-up (mean, 19.5 months; range, 6-24 months), pain persisted in two patients after 2 months. Both of them were re-treated. All patients are currently pain-free and complications were not detected. In our opinion, radiofrequency ablation can also be considered the treatment of choice for spinal osteoid osteoma.

  5. Should fat in the radiofrequency ablation zone of hepatocellular adenomas raise suspicion for residual tumour?

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Andreu F. [University Health Network and Mount Sinai Hospital, University of Toronto, Joint Department of Medical Imaging, Toronto, Ontario (Canada); Dalhousie University, Department of Diagnostic Radiology, QE II Health Sciences Centre - VG Site, Halifax, Nova Scotia (Canada); Kajal, Dilkash; Pereira, Andre; Atri, Mostafa [University Health Network and Mount Sinai Hospital, University of Toronto, Joint Department of Medical Imaging, Toronto, Ontario (Canada)

    2017-04-15

    To assess the significance of fat in the radiofrequency ablation (RFA) zone of hepatocellular adenomas (HCA), and its association with tumoral fat and hepatic steatosis. The radiological archive was searched for patients with ablated HCAs and follow-up magnetic resonance imaging between January 2008 and June 2014. Age, sex, risk factors and duration of clinical and imaging follow-up were recorded. Pre-RFA imaging was assessed for tumour size, intra-tumoral fat and steatosis. Post-RFA imaging was reviewed for size, enhancement and intra-ablational fat. Intra-ablational fat was classified as peripheral, central or mixed; the association of these distributions with steatosis and tumoral fat was assessed using Fisher's exact test. Sixteen patients with 26 ablated HCAs were included. Fat was present in 23/26 (88 %) ablation zones. Only 1/26 (4 %) showed serial enlargement and enhancement suggestive of residual disease; the enhancing area did not contain fat. All remaining ablations showed involution and/or diminishing fat content without suspicious enhancement (mean follow-up, 27 months; range, 2-84 months). The peripheral and mixed/central patterns of intra-ablational fat were associated with steatosis (P = 0.0005) and tumoral fat (P = 0.0003), respectively. Fat in the ablation zone of HCAs is a common finding which, in isolation, does not indicate residual tumour. (orig.)

  6. Liver tumor gross margin identification and ablation monitoring during liver radiofrequency treatment.

    Science.gov (United States)

    Hsu, Christopher P; Razavi, Mahmood K; So, Samuel K; Parachikov, Ilian H; Benaron, David A

    2005-11-01

    To determine whether tissue visible light spectroscopy (VLS) used during radiofrequency (RF) ablation of liver tumors could aid in detecting when tissue becomes adequately ablated, locate grossly ablated regions long after temperature and hydration measures would no longer be reliable, and differentiate tumor from normal hepatic tissue based on VLS spectral characteristics. Studies were performed on human liver in vivo and animal liver ex vivo. In three ex vivo cow livers, RF-induced lesions were created at 80 degrees C. A 28-gauge needle embedded with VLS optical fibers was inserted alongside an RF ablation array, and tissue spectral characteristics were recorded throughout ablation. In one anesthetized sheep in vivo, a VLS needle probe was passed through freshly ablated liver lesions, and ablated region spectral characteristics were recorded during probe transit. In two human subjects, a VLS needle probe was passed through liver tumors in patients undergoing hepatic tumor resection without ablation, and tumor spectral characteristics were recorded during probe transit. In bovine studies, there was significant change in baseline absorbance (P gross ablation margins were clearly defined with millimeter resolution during needle transit through the region, suggesting that VLS is sensitive to gross margins of ablation, even after the temperature has normalized. In humans, absorbance decreased as the needle passed from normal tissue into tumor and normalized after emerging from the tumor, suggesting that absence of native liver pigment may serve as a marker for the gross margins and presence of tumors of extrahepatic origin. In human subjects, VLS during RF liver tumor ablation depicted gross hepatic tumor margins in real time; in animal subjects, VLS achieved monitoring of when and where RF ablation endpoints were achieved, even long after the tissue cooled. Real-time in vivo monitoring and treatment feedback may be possible with the use of real-time VLS sensors

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

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jonathan K., E-mail: jonathan.park09@gmail.com [David Geffen School of Medicine at UCLA, Department of Radiology (United States); Al-Tariq, Quazi Z., E-mail: qat200@gmail.com [Stanford University School of Medicine, Department of Radiology (United States); Zaw, Taryar M., E-mail: taryar.zaw@gmail.com; Raman, Steven S., E-mail: sraman@mednet.ucla.edu; Lu, David S.K., E-mail: dlu@mednet.ucla.edu [David Geffen School of Medicine at UCLA, Department of Radiology (United States)

    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.

  8. Percutaneous treatment of hepatocellular carcinoma in patients with cirrhosis: A comparison of the safety of cryoablation and radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Dunne, Ruth M., E-mail: rmdunne@partners.org [Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Shyn, Paul B., E-mail: pshyn@partners.org [Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Sung, Jeffrey C., E-mail: jcsung@gmail.com [Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Tatli, Servet, E-mail: statli@partners.org [Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Morrison, Paul R. [Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Catalano, Paul J., E-mail: pcata@jimmy.harvard.edu [Department of Biostatistics and Computational Biology, Dana Farber Cancer Institute, 450 Brookline Avenue, CLSB 11007, Boston, MA 02215 (United States); Department of Biostatistics, Harvard School of Public Health, Boston, MA 02215 (United States); Silverman, Stuart G., E-mail: sgsilverman@partners.org [Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States)

    2014-04-15

    Purpose: To compare the safety of image-guided percutaneous cryoablation and radiofrequency ablation in the treatment of hepatocellular carcinoma in patients with cirrhosis. Materials and methods: This retrospective HIPAA-compliant study received institutional review board approval. Forty-two adult patients with cirrhosis underwent image-guided percutaneous ablation of hepatocellular carcinoma from 2003 to 2011. Twenty-five patients underwent 33 cryoablation procedures to treat 39 tumors, and 22 underwent 30 radiofrequency ablation procedures to treat 39 tumors. Five patients underwent both cryoablation and radiofrequency ablation procedures. Complication rates and severity per procedure were compared between the ablation groups. Potential confounding patient, procedure, and tumor-related variables were also compared. Statistical analyses included Kruskal–Wallis, Wilcoxon rank sum, and Fisher's exact tests. Two-sided P-values <0.05 were considered significant. Results: The overall complication rates, 13 (39.4%) of 33 cryoablation procedures versus eight (26.7%) of 30 radiofrequency ablation procedures and severe/fatal complication rates, two (6.1%) of 33 cryoablation procedures versus one (3.3%) of 30 radiofrequency ablation procedures, were not significantly different between the ablation groups (both P = 0.26). Severe complications included pneumothoraces requiring chest tube insertion during two cryoablation procedures. One death occurred within 90 days of a radiofrequency ablation procedure; all other complications were managed successfully. Conclusion: No significant difference was seen in the overall safety of image-guided percutaneous cryoablation and radiofrequency ablation in the treatment of hepatocellular carcinoma in patients with cirrhosis.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mizandari, Malkhaz [Tbilisi State Medical University, Department of Radiology (Georgia); Pai, Madhava, E-mail: madhava.pai@imperial.ac.uk; Xi Feng [Imperial College, London, Hammersmith Hospital Campus, Department of Surgery (United Kingdom); Valek, Vlastimil; Tomas, Andrasina [University Hospital Brno Bohunice, Department of Radiology (Czech Republic); Quaretti, Pietro [IRCCS Policlinico San Matteo, Department of Radiology (Italy); Golfieri, Rita; Mosconi, Cristina [University of Bologna, Department of Radiology, Policlinico S. Orsola-Malpighi (Italy); Ao Guokun [The 309 Hospital of Chinese PLA, Department of Radiology (China); Kyriakides, Charis [Imperial College, London, Hammersmith Hospital Campus, Department of Surgery (United Kingdom); Dickinson, Robert [Imperial College London, Department of Bioengineering (United Kingdom); Nicholls, Joanna; Habib, Nagy, E-mail: nagy.habib@imperial.ac.uk [Imperial College, London, Hammersmith Hospital Campus, Department of Surgery (United Kingdom)

    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.

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

    NARCIS (Netherlands)

    Bergman, Jacques J. G. H. M.; Zhang, Yue-Ming; He, Shun; Weusten, Bas; Xue, Liyan; Fleischer, David E.; Lu, Ning; Dawsey, Sanford M.; Wang, Gui-Qi

    2011-01-01

    Radiofrequency ablation (RFA) is safe and effective for eradicating neoplasia in Barrett's esophagus. To evaluate RFA for eradicating early esophageal squamous cell neoplasia (ESCN) defined as moderate-grade squamous intraepithelial neoplasia (MGIN) and high-grade squamous intraepithelial neoplasia

  11. Combined use of radioiodine therapy and radiofrequency ablation in treating postsurgical thyroid remnant of differentiated thyroid carcinoma

    Directory of Open Access Journals (Sweden)

    Bin Long

    2015-01-01

    Conclusion: Combined use of RAI therapy and radiofrequency ablation in treating excessive postsurgical thyroid remnant of DTC can be an effective approach and avoids re-operation. Long-term efficacy monitoring would further determine its feasibility.

  12. Diluted hydrochloric acid generates larger radiofrequency ablation lesions in excised porcine livers.

    Science.gov (United States)

    Luo, Rong-Guang; Fao, Fei; Huang, Jin-Hua; Gu, Yang-Kui; Jiang, Xiong-Ying; Huang, Ying-Jie

    2013-01-01

    This study evaluated the influence of continuous infusion of diluted hydrochloric acid during radiofrequency ablation (RFA) on the size of ablated lesions. Experiments were performed in 20 excised porcine livers using three different treatment modalities: (1) normal saline-enhanced RFA (NS-RFA), which was normal saline pumped into ablated tissue during RFA; (2) diluted hydrochloric acid ablation (DHAA), which was 3 mol/L diluted hydrochloric acid (HCl) injected into hepatic tissue without RFA; and (3) HCl-enhanced RFA (HCl-RFA), which was 3 mol/L diluted HCl continuously infused into ablated tissue during RFA. We produced 20 HCl-RFA and NS-RFA lesions, respectively, using a monopolar perfusion electrode connected to a commercially available radiofrequency generator, and 20 DHAA lesions using an 18-gauge Chiba needle. The ablated lesions were evaluated both macroscopically and histologically. Dimensions of lesions were compared among HCl-RFA, NS-RFA, and DHAA. The ablated lesions had an elliptical-like shape and were well-demarcated with normal liver tissue. The mean volume, longitudinal diameter, and transverse diameter of NS-RFA lesions were 11.24±0.29 cm(3), 3.4±0.07 cm, and 2.48±0.03 cm, those of HCl-RFA lesions were 58.14±3.05 cm(3), 5.51±0.05 cm, and 4.49±0.11 cm, and those of DHAA lesions were 4.41±0.16 cm(3), 2.43±0.08 cm, and 1.8±0.03 cm, respectively. The mean dimensions of HCl-RFA lesions were the largest among the three types of ablation (P < 0.001). Under the present experimental conditions, the continuous infusion of diluted HCl during RFA can generate larger ablated lesions than NS-RFA or DHAA in excised porcine livers.

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

    Science.gov (United States)

    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

  14. Percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation

    Energy Technology Data Exchange (ETDEWEB)

    Akhlaghpoor, S. [Noor Medical Imaging Center, Tehran (Iran, Islamic Republic of)]. E-mail: akhlaghpoor@nmri-ir.com; Tomasian, A. [Noor Medical Imaging Center, Tehran (Iran, Islamic Republic of); Arjmand Shabestari, A. [Noor Medical Imaging Center, Tehran (Iran, Islamic Republic of); Ebrahimi, M. [Noor Medical Imaging Center, Tehran (Iran, Islamic Republic of); Alinaghizadeh, M.R. [Noor Medical Imaging Center, Tehran (Iran, Islamic Republic of)

    2007-03-15

    Aim: To assess the efficacy of percutaneous osteoid osteoma treatment using a combination of radiofrequency ablation (RFA) and alcohol ablation with regard to technical and long-term clinical success. Materials and methods: From December 2001 to November 2004, RFA and subsequent alcohol ablation was performed on 54 patients with osteoid osteoma, diagnosed clinically using radiography, computed tomography (CT) and symptoms. Under general anaesthesia, treatment was performed via percutaneous access under thin section (2 mm) spiral CT guidance in all cases with an 11 G radiofrequency-compatible coaxial needle and 2 mm coaxial drill system and 1.0 cm active tip 17 G non-cooled radiofrequency needle. RFA was performed at 90 {sup o}C for a period of 6 min. After needle removal, 0.5-1.0 ml absolute alcohol (99.8% concentration) was injected directly into the nidus using a 20 G needle. Patients were discharged within 24 h and followed up clinically (at 1 week, 1 month and every 3 months thereafter). Results: The technical success rate was 100%. Complications occurred in two patients consisting of local mild cellulitis in entry site and peripheral small zone paresthesia on the anterior part of leg. The follow-up period range was 13-48 months (mean {+-} SD, 28.2 {+-} 7.4 months). Prompt pain relief and return to normal activities were observed in 52 of 54 patients. Recurrent pain occurred in two patients after a 1 and 3 months period of being pain free, respectively; a second RFA and alcohol ablation was performed achieving successful results. Primary and secondary clinical success rates were 96.3% (52/54 patients) and 100% (2/2 patients), respectively. Conclusion: Percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation is safe, effective and minimally invasive with high primary and secondary success rates. Persistent or recurrent lesions can be effectively re-treated.

  15. Assessment of ablative margin by MRI with ferucarbotran in radiofrequency ablation for liver cancer: comparison with enhanced CT

    Science.gov (United States)

    Tokunaga, S; Koda, M; Matono, T; Sugihara, T; Nagahara, T; Ueki, M; Murawaki, Y; Kakite, S; Yamashita, E

    2012-01-01

    Objectives Our aim was to determine whether ablated liver parenchyma surrounding a tumour can be assessed by MRI with ferucarbotran administered prior to radiofrequency ablation (RFA) compared with enhanced CT. Methods 55 hepatocellular carcinomas (HCCs) in 42 patients and 5 metastatic liver cancers in 3 patients were treated by RFA after ferucarbotran administration. We then performed T2* weighted MRI after 1 week and enhanced CT after 1 month. T2* weighted MRI demonstrated the ablated parenchyma as a low-intensity rim around the high intensity of the ablated tumour in these cases. The assessment was allocated to one of three grades: margin (+), high-intensity area with continuous low-intensity rim; margin zero, high-intensity area with discontinuous low-intensity rim; and margin (−), high-intensity area extending beyond the low-intensity rim. Results Margin (+), margin zero and margin (−) were found in 17, 35 and 5 nodules, respectively. All 17 nodules with margin (+) and 13 of those with margin zero were assessed as having sufficient abalative margins on CT. The remaining 22 nodules with margin zero had insufficient margins on CT. The overall agreement between MRI and CT for the diagnosis of the ablative margin was moderate (κ=0.507, pablative margin to be visualised as a low-intensity rim, and also enables the evaluation of the ablative margin to be made earlier and more easily than with enhanced CT. PMID:21385915

  16. Temperature-controlled irrigated tip radiofrequency catheter ablation: comparison of in vivo and in vitro lesion dimensions for standard catheter and irrigated tip catheter with minimal infusion rate

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, A

    1998-01-01

    In patients with ventricular tachycardias due to structural heart disease, catheter ablation cures <60% partly due to the limited lesion size after conventional radiofrequency ablation. Irrigated tip radiofrequency ablation using power control and high infusion rates enlarges lesion size, but has...

  17. Effect of nonparallel placement of in-circle bipolar radiofrequency ablation probes on volume of tissue ablated with heat sink.

    Science.gov (United States)

    Pillai, Krishna; Al-Alem, Ihssan; Akhter, Javed; Chua, Terence C; Shehata, Mena; Morris, David L

    2015-06-01

    Percutaneous bipolar radiofrequency ablation (RFA) is a minimally invasive technique for treating liver tumors. It is not always possible to insert the bipolar probes parallel to each other on either side of tumor, since it restricts maneuverability away from vital structures or ablate certain tumor shape. Therefore, we investigated how nonparallel placement of probes affected ablation. Bipolar RFA in parallel and in divergent positions were submerged in tissue model (800 mL egg white) at 37°C and ablated. Temperature probes, T1 and T2 were placed 8.00 mm below the tip of the probes, T3 in between the probe coil elements and T4 and T5 at water inlet and outlet, respectively. Both models with heat sink (+HS) and without (-HS) were investigated. The mean ablated tissue volume, mass, density and height increased linearly with unit angle increase for -HS model. With +HS, a smaller increase in mean volume and mass, a slightly greater increase in mean density but a reduction in height of tissue was seen. The mean ablation time and duration of maximum temperature with +HS was slightly larger, compared with -HS, while -HS ablated at a slightly higher temperature. The heat sink present was minimal for probes in parallel position compared to nonparallel positions. Divergence from parallel insertion of bipolar RFA probes increased the mean volume, mass, and density of tissue ablated. However, the presence of large heat sinks may limit the application of this technique, when tumors border on larger vessels. © The Author(s) 2014.

  18. Submucosal resection of a microcystic oropharyngeal lymphatic malformation using radiofrequency ablation.

    Science.gov (United States)

    Thottam, Prasad John; Al-Barazi, Randa; Madgy, David N; Rozzelle, Arlene

    2013-09-01

    Lymphatic malformations (LMs) are uncommon congenital anomalies noted to have a prevalence of 1 per 5000 births and comprise roughly 6% of all pediatric soft tissue lesions. Recently radiofrequency ablation has been described as a surgical option for the treatment microcystic LMs in the oral cavity, more specifically the tongue. The following case describes the use of radiofrequency ablation for the submucosal removal of a large obstructing pharyngeal LM in a 4-year-old female. The mucosal sparing approach and surgical method of extirpation are discussed in detail. To the authors' knowledge this is the first description of a submucosal coblation technique being used as treatment for pharyngeal LMs. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Value of radiofrequency ablation in the management of retropharyngeal lymphatic malformation.

    Science.gov (United States)

    Lisan, Quentin; Villepelet, Aude; Parodi, Marine; Garabedian, Eréa-Noël; Blouin, Marie Julie; Couloigner, Vincent; Leboulanger, Nicolas

    2016-04-01

    Lymphatic malformations are benign malformations frequently occurring in the head and neck. Retropharyngeal location is rare, can be life threating and its management is particularly challenging. Over a three-year period, three patients presented with symptomatic (dyspnea and/or dysphagia) retropharyngeal lymphatic malformation. All were treated using a radiofrequency ablation of lymphatic malformation through a trans-oral approach. No major complications occurred following the surgery. During the follow-up, no recurrence was noted and all patients were asymptomatic. Radiofrequency ablation in the management of retropharyngeal lymphatic malformations is a simple technique with very good results and allows a fast recovery with minimum morbidity and a short hospital stay. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Percutaneous radiofrequency ablation of liver cancer in the hepatic dome using the intrapleural fluid infusion technique.

    Science.gov (United States)

    Kondo, Y; Yoshida, H; Tateishi, R; Shiina, S; Kawabe, T; Omata, M

    2008-08-01

    Intrapleural fluid infusion improves ultrasonographic visualization of tumours in the hepatic dome. The aim of this study was to assess the safety and long-term efficacy of ultrasonographically guided percutaneous radiofrequency ablation for tumours in the hepatic dome with intrapleural infusion. Of 2575 patients with hepatocellular carcinoma or hepatic metastases treated with radiofrequency ablation, intrapleural fluid infusion was performed in 587 patients for tumours in the hepatic dome. After the tip of a 14-G metallic needle was positioned in the pleural cavity under ultrasonographic guidance, 500-1000 ml of 5 per cent glucose solution was infused in 5-15 min. Radiofrequency ablation was performed using an internally cooled electrode. Long-term results were evaluated in 347 patients with a single hepatocellular carcinoma who were naive to any treatment. Intrapleural fluid infusion was successfully performed in all 587 patients. The major complication rate on a per tumour basis was similar for patients treated with and without intrapleural infusion (1.6 versus 1.6 per cent; P = 0.924). The overall and recurrence-free survival were both similar for naive patients with a single hepatocellular carcinoma treated with and without intrapleural infusion (P = 0.429 and P = 0.109 respectively). Intrapleural infusion was not associated with lower overall survival in multivariable analysis. With intrapleural fluid infusion, radiofrequency ablation for tumours in the hepatic dome was safe and effective, resulting in satisfactory overall and recurrence-free survival. Copyright (c) 2008 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

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

    Directory of Open Access Journals (Sweden)

    Salem Bauones

    2015-01-01

    Full Text Available 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.

  2. New horizons in MR-controlled and monitored radiofrequency ablation of liver tumours

    OpenAIRE

    Cernicanu, Alexandru; Lepetit-Coiff?, Matthieu; Viallon, Magalie; Terraz, Sylvain; Becker, Christoph D.

    2007-01-01

    Abstract There is a sustained interest in using magnetic resonance (MR) thermometry to monitor the radiofrequency ablation of liver tumours as a means of visualizing the progress of the thermal coagulation and deciding the optimal end-point. Despite numerous technical challenges, important progress has been made and demonstrated in animal studies. In addition to MR thermometry, MR can now be used for the guidance of the tumour targeting with ?fluoroscopic? rapid image acquisition, and it can ...

  3. Biliary peritonitis after radiofrequency ablation diagnosed by gadoxetic acid-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Akihiro; Isoda, Hiroyoshi; Togashi, Kaori [Dept. of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto (Japan); Koyama, Takashi; Todo, Giro; Osaki, Yukio [Osaka Red Cross Hospital, Osaka (Japan)

    2013-12-15

    This study describes the first case of biliary peritonitis after radiofrequency ablation diagnosed by magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA), a hepatocyte-specific MR imaging contrast agent. The image acquired 300 minutes after the administration of Gd-EOB-DTPA was useful to make a definite diagnosis and to identify the pathway of bile leakage. It is important to decide on the acquisition timing with consideration of the predicted location of bile duct injury.

  4. Radiofrequency ablation of a cervical osteoid osteoma: a trans-thyroid approach

    Energy Technology Data Exchange (ETDEWEB)

    Sutphen, Sean A.; Murakami, James W. [Columbus Children' s Hospital, Children' s Radiological Institute, Columbus, OH (United States)

    2007-01-15

    We present a 16-year-old girl with an osteoid osteoma in the vertebral body of C5. Given the difficulty of surgically treating the lesion, radiofrequency ablation was used. Percutaneous needle access to this lesion in the anterior aspect of the cervical vertebral body was limited by the many critical adjacent structures. We present our successful treatment of this lesion utilizing a transthyroid needle approach. (orig.)

  5. [The new technology of enhanced radiofrequency ablation is safe and effective for treating giant hepatic hemangioma].

    Science.gov (United States)

    Zou, Hua; Yan, Jun; Wu, Yan-xia; Ou, Xia; Li, Xiao-wu; Xia, Feng; Ma, Kuan-sheng; Bie, Ping

    2012-04-01

    To determine the safety and efficacy of the enhanced radiofrequency ablation (RFA) new technology for treatment of giant hepatic hemangiomas. From August 2010 to September 2011, 30 patients with giant hepatic hemangiomas (average diameter: 7.7+/-1.9 cm, range: 5.0 to 12.8 cm) were treated with enhanced RFA. The original lesion diameter, enhanced radiofrequency duration, and cases of RFA-induced burning were recorded. Cases requiring a second RFA treatment were also recorded. Correlation analysis was carried out to determine the association of enhanced RFA with adverse events and change in lesion diameter. The rate of completely destroyed lesions by enhanced RFA was 70.96%, and the total rate of reduced lesions was 87.1%. No severe adverse events occurred. The duration of enhanced radiofrequency correlated positively with the original lesion diameter (r=0.687, P less than 0.01). The enhanced RFA treatment significantly reduced the average lesion diameter (follow-up: 6.2+/-1.8 cm; t=6.417, P less than 0.01). The new minimally-invasive technology of enhanced radiofrequency ablation is effective and safe for treating giant hepatic hemangiomas and produces an obvious, short-term curative effect.

  6. Bipolar radiofrequency ablation of liver metastases during laparotomy. First clinical experiences with a new multipolar ablation concept.

    Science.gov (United States)

    Ritz, Joerg-Peter; Lehmann, Kai S; Reissfelder, Christoph; Albrecht, Thomas; Frericks, Bernd; Zurbuchen, Urte; Buhr, Heinz J

    2006-01-01

    Radiofrequency ablation (RFA) is a promising method for local treatment of liver malignancies. Currently available systems for radiofrequency ablation use monopolar current, which carries the risk of uncontrolled electrical current paths, collateral damages and limited effectiveness. To overcome this problem, we used a newly developed internally cooled bipolar application system in patients with irresectable liver metastases undergoing laparotomy. The aim of this study was to clinically evaluate the safety, feasibility and effectiveness of this new system with a novel multipolar application concept. Patients with a maximum of five liver metastases having a maximum diameter of 5 cm underwent laparotomy and abdominal exploration to control resectability. In cases of irresectability, RFA with the newly developed bipolar application system was performed. Treatment was carried out under ultrasound guidance. Depending on tumour size, shape and location, up to three applicators were simultaneously inserted in or closely around the tumour, never exceeding a maximum probe distance of 3 cm. In the multipolar ablation concept, the current runs alternating between all possible pairs of consecutively activated electrodes with up to 15 possible electrode combinations. Post-operative follow-up was evaluated by CT or MRI controls 24-48 h after RFA and every 3 months. In a total of six patients (four male, two female; 61-68 years), ten metastases (1.0-5.5 cm) were treated with a total of 14 RF applications. In four metastases three probes were used, and in another four and two metastases, two and one probes were used, respectively. During a mean ablation time of 18.8 min (10-31), a mean energy of 48.8 kJ (12-116) for each metastases was applied. No procedure-related complications occurred. The patients were released from the hospital between 7 and 12 days post-intervention (median 9 days). The post-interventional control showed complete tumour ablation in all cases. Bipolar

  7. Mathematical 3D modelling and sensitivity analysis of multipolar radiofrequency ablation in the spine.

    Science.gov (United States)

    Matschek, Janine; Bullinger, Eric; von Haeseler, Friedrich; Skalej, Martin; Findeisen, Rolf

    2017-02-01

    Radiofrequency ablation is a valuable tool in the treatment of many diseases, especially cancer. However, controlled heating up to apoptosis of the desired target tissue in complex situations, e.g. in the spine, is challenging and requires experienced interventionalists. For such challenging situations a mathematical model of radiofrequency ablation allows to understand, improve and optimise the outcome of the medical therapy. The main contribution of this work is the derivation of a tailored, yet expandable mathematical model, for the simulation, analysis, planning and control of radiofrequency ablation in complex situations. The dynamic model consists of partial differential equations that describe the potential and temperature distribution during intervention. To account for multipolar operation, time-dependent boundary conditions are introduced. Spatially distributed parameters, like tissue conductivity and blood perfusion, allow to describe the complex 3D environment representing diverse involved tissue types in the spine. To identify the key parameters affecting the prediction quality of the model, the influence of the parameters on the temperature distribution is investigated via a sensitivity analysis. Simulations underpin the quality of the derived model and the analysis approach. The proposed modelling and analysis schemes set the basis for intervention planning, state- and parameter estimation, and control. Copyright © 2016. Published by Elsevier Inc.

  8. Effects of Arsenic Trioxide on Radiofrequency Ablation of VX2 Liver Tumor: Intraarterial versus Intravenous Administration

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Nak Jong; Yoon, Chang Jin; Kang, Sung Gwon [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Chung, Jin Wook; Kim, Hyo Cheol; Park, Jae Hyung [Seoul National University Hospital, Seoul (Korea, Republic of)

    2012-03-15

    Arsenic trioxide (As{sub 2}O{sub 3}) can be used as a possible pharmaceutical alternative that augments radiofrequency (RF) ablation by reducing tumor blood flow. The aim of this study was to assess the effect of intraarterial and intravenous administration of As{sub 2}O{sub 3} on RF-induced ablation in an experimentally induced liver tumor. VX2 carcinoma was grown in the livers of 30 rabbits. As{sub 2}O{sub 3} (1 mg/kg) was administered through the hepatic artery (n = 10, group A) or ear vein (n = 10, group B), 30 minutes before RF ablation (125 mA {+-} 35; 90 {+-} 5 degrees Celsius). As a control group, 10 rabbits were treated with RF ablation alone (group C). RF was intentionally applied to the peripheral margin of the tumor so that ablation can cover the tumor and adjacent hepatic parenchyma. Ablation areas of the tumor and adjacent parenchymal changes among three groups were compared by the Kruskal-Wallis and Mann-Whitney U test. The overall ablation areas were 156 {+-} 28.9 mm{sup 2} (group A), 119 {+-} 31.7 (group B), and 92 {+-} 17.4 (group C, p < 0.04). The ablation area of the tumor was significantly larger in group A (73 {+-} 19.7 mm{sup 2}) than both group B (50 {+-} 19.4, p = 0.02) and group C (28 {+-} 2.2, p < 0.01). The ratios of the tumoral ablation area to the overall ablation area were larger in group A (47 {+-} 10.5%) than that of the other groups (42 {+-} 7.3% in group B and 32 {+-} 5.6% in group C) (p < 0.03). Radiofrequency-induced ablation area can be increased with intraarterial or intravenous administration of As{sub 2}O{sub 3}. The intraarterial administration of As{sub 2}O{sub 3} seems to be helpful for the selective ablation of the tumor.

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

    Science.gov (United States)

    Steinbeck, G

    1993-03-01

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

  10. Treatment of trigeminal neuralgia: role of radiofrequency ablation

    Directory of Open Access Journals (Sweden)

    Dessy R Emril

    2010-12-01

    Full Text Available Dessy R Emril1 Kok-Yuen Ho21Neurology Department, Syiah Kuala University/Dr Zainoel Abidin Hospital, Banda Aceh, Indonesia; 2Pain Management Centre, Raffles Hospital, SingaporeAbstract: Trigeminal neuralgia (TN is a neuropathic pain condition affecting the face. It has a significant impact on the quality of life and physical function of patients. Evidence suggests that the likely etiology is vascular compression of the trigeminal nerve leading to focal demyelination and aberrant neural discharge. Secondary causes such as multiple sclerosis or brain tumors can also produce symptomatic TN. Treatment must be individualized to each patient. Carbamazepine remains the drug of choice in the first-line treatment of TN. Minimally invasive interventional pain therapies and surgery are possible options when drug therapy fails. Younger patients may benefit from microvascular decompression. Elderly patients with poor surgical risk may be more suitable for percutaneous trigeminal nerve rhizolysis. The technique of radiofrequency rhizolysis of the trigeminal nerve is described in detail in this review.Keywords: interventional treatment, minimally invasive, pain management, radiofrequency rhizolysis, trigeminal neuralgia 

  11. Laser Guidance in C-Arm Cone-Beam CT-Guided Radiofrequency Ablation of Osteoid Osteoma Reduces Fluoroscopy Time

    NARCIS (Netherlands)

    Kroes, M.W.; Busser, W.M.H.; Hoogeveen, Y.L.; Lange, F. de; Schultze Kool, L.J.

    2017-01-01

    PURPOSE: To assess whether laser guidance can reduce fluoroscopy and procedure time of cone-beam computed tomography (CBCT)-guided radiofrequency (RF) ablations of osteoid osteoma compared to freehand CBCT guidance. MATERIALS AND METHODS: 32 RF ablations were retrospectively analyzed, 17

  12. Atrial mapping and radiofrequency catheter ablation in patients with idiopathic atrial fibrillation. Electrophysiological findings and ablation results.

    Science.gov (United States)

    Gaita, F; Riccardi, R; Calò, L; Scaglione, M; Garberoglio, L; Antolini, R; Kirchner, M; Lamberti, F; Richiardi, E

    1998-06-02

    Knowledge of the electrophysiological substrates and the cure of atrial fibrillation (AF) is still unsatisfactory. The goal of this study was to evaluate the electrophysiological features of idiopathic AF and their relationship to the results of radiofrequency (RF) catheter ablation of AF and the safety and effectiveness of this procedure. Sixteen patients with idiopathic AF underwent atrial mapping during AF and then RF ablation in the right atrium. The atrial activation was simultaneously recorded in four regions in the right atrium: high lateral wall (HL), low lateral wall (LL), high septum (HS), and low septum (LS) and in the left atrium through the coronary sinus (CS). In these regions, we evaluated the atrial fibrillation intervals (FF) and the morphological features of AF recordings by Wells' classification. No complications occurred during RF ablation. Of the 16 patients, 9 (56%) without AF recurrences during the follow-up (11 +/- 4 months) were considered successfully ablated. These patients showed a significantly shorter mean FF interval in the HS and the LS (122 +/- 32 and 126 +/- 28 ms, respectively), than in the HL and LL (159 +/- 24 and 156 +/- 28 ms, respectively). Moreover, the septum had more irregular electrical activity with greater beat-to-beat changes in FF and a higher prevalence of type III AF than the lateral region. The CS had similar behavior to the septum. Conversely, patients with unsuccessful ablation had an irregular atrial activity in the lateral wall, septum, and CS with no significant differences between the different sites. Right atrial endocardial catheter ablation of AF is a safe procedure and may be effective in some patients with idiopathic AF. The atrial mapping during AF showed a more disorganized right atrial activation in the septum than in the lateral wall in patients with successful ablation.

  13. Insights into energy delivery to myocardial tissue during radiofrequency ablation through application of the first law of thermodynamics.

    Science.gov (United States)

    Bunch, T Jared; Day, John D; Packer, Douglas L

    2009-04-01

    The approach to catheter-based radiofrequency ablation of atrial fibrillation has evolved, and as a consequence, more energy is delivered in the posterior left atrium, exposing neighboring tissue to untoward thermal injury. Simultaneously, catheter technology has advanced to allow more efficient energy delivery into the myocardium, which compounds the likelihood of collateral injury. This review focuses on the basic principles of thermodynamics as they apply to energy delivery during radiofrequency ablation. These principles can be used to titrate energy delivery and plan ablative approaches in an effort to minimize complications during the procedure.

  14. Radiofrequency catheter ablation in patients with symptomatic atrial flutter/tachycardia after orthotopic heart transplantation.

    Science.gov (United States)

    Li, Yi-gang; Grönefeld, Gerian; Israel, Carsten; Lu, Shang-biao; Wang, Qun-shan; Hohnloser, Stefan H

    2006-12-20

    Atrial tachycardia or flutter is common in patients after orthotopic heart transplantation. Radiofrequency catheter ablation to treat this arrhythmia has not been well defined in this setting. This study was conducted to assess the incidence of various symptomatic atrial arrhythmias and the efficacy and safety of radiofrequency catheter ablation in these patients. Electrophysiological study and catheter ablation were performed in patients with symptomatic tachyarrhythmia. One Halo catheter with 20 poles was positioned around the tricuspid annulus of the donor right atrium, or positioned around the surgical anastomosis when it is necessary. Three quadripolar electrode catheters were inserted via the right or left femoral vein and positioned in the recipient atrium, the bundle of His position, the coronary sinus. Programmed atrial stimulation and burst pacing were performed to prove electrical conduction between the recipient and the donor atria and to induce atrial arrhythmias. Out of 55 consecutive heart transplantation patients, 6 males [(58 +/- 12) years] developed symptomatic tachycardias at a mean of (5 +/- 4) years after heart transplantation. Electrical propagation through the suture line between the recipient and the donor atrium was demonstrated during atrial flutter or during recipient atrium and donor atrium pacing in 2 patients. By mapping around the suture line, the earliest fragmented electrogram of donor atrium was assessed. This electrical connection was successfully ablated in the anterior lateral atrium in both patients. There was no electrical propagation through the suture line in the other 4 patients. Two had typical atrial flutter in the donor atrium which was successfully ablated by completing a linear ablation between the tricuspid annulus and the inferior vena cava. Two patients had atrial tachycardia which was ablated in the anterior septal and lateral donor atrium. There were no procedure-related complications. Patients were free of

  15. Prognostic impact of hs-CRP and IL-6 in patients undergoing radiofrequency catheter ablation for atrial fibrillation

    DEFF Research Database (Denmark)

    Henningsen, Kristoffer Mads Aaris; Nilsson, Brian; Bruunsgaard, Helle

    2008-01-01

    Aim. The aim of this study was to assess the predictive value of inflammatory markers in patients with paroxysmal/ persistent atrial fibrillation (AF) treated with radiofrequency (RF) catheter ablation. Methods. Forty-six consecutive patients, mean age 55 years (range 31 - 81 yrs), with paroxysmal...... of paroxysmal or persistent AF treated with RF catheter ablation, elevated levels of IL-6 and hs-CRP before ablation are independent predictors of recurrence of AF Udgivelsesdato: 2008/12/31...

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

    Science.gov (United States)

    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.

  17. Visualization and Attentive Behavior for Pain Reduction during Radiofrequency Ablation of Atrial Fibrillation

    DEFF Research Database (Denmark)

    Nørgaard, Marianne W; Werner, Anette; Abrahamsen, Randi

    2013-01-01

    pain, the amount of analgesics, anxiety, and adverse events. METHODS: A clinical controlled study with 71 patients in a control group (CG), receiving conventional care and treatment, and 76 patients in an intervention group (IG), receiving relaxation and visualization, combined with a structured......BACKGROUND: Radiofrequency (RF) ablation of atrial fibrillation (AF) can be accompanied by pain and anxiety when light conscious sedation is used. We sought to determine how visualization and structured attentive behavior during ablation of AF could reduce pain intensity, spontaneously expressed...... of anxiety, mean anxiety: CG (0.10-1.84), IG (0.9-2.03)(NS), and the number of adverse events (P = 0.241). CONCLUSION: Visualization and structured attentive behavior was shown to reduce the amount of analgesics during the RF ablation of AF. There was no difference in perception of pain intensity...

  18. Comprehensive preclinical evaluation of a multi-physics model of liver tumor radiofrequency ablation.

    Science.gov (United States)

    Audigier, Chloé; Mansi, Tommaso; Delingette, Hervé; Rapaka, Saikiran; Passerini, Tiziano; Mihalef, Viorel; Jolly, Marie-Pierre; Pop, Raoul; Diana, Michele; Soler, Luc; Kamen, Ali; Comaniciu, Dorin; Ayache, Nicholas

    2017-09-01

    We aim at developing a framework for the validation of a subject-specific multi-physics model of liver tumor radiofrequency ablation (RFA). The RFA computation becomes subject specific after several levels of personalization: geometrical and biophysical (hemodynamics, heat transfer and an extended cellular necrosis model). We present a comprehensive experimental setup combining multimodal, pre- and postoperative anatomical and functional images, as well as the interventional monitoring of intra-operative signals: the temperature and delivered power. To exploit this dataset, an efficient processing pipeline is introduced, which copes with image noise, variable resolution and anisotropy. The validation study includes twelve ablations from five healthy pig livers: a mean point-to-mesh error between predicted and actual ablation extent of 5.3 ± 3.6 mm is achieved. This enables an end-to-end preclinical validation framework that considers the available dataset.

  19. Guidelines for predicting lesion size at common endocardial locations during radio-frequency ablation.

    Science.gov (United States)

    Tungjitkusolmun, S; Vorperian, V R; Bhavaraju, N; Cao, H; Tsai, J Z; Webster, J G

    2001-02-01

    We used the finite element method to study the effect of radio-frequency (RF) catheter ablation on tissue heating and lesion formation at different intracardiac sites exposed to different regional blood velocities. We examined the effect of application of RF current in temperature- and power-controlled mode above and beneath the mitral valve annulus where the regional blood velocities are high and low respectively. We found that for temperature-controlled ablation, more power was delivered to maintain the preset tip temperature at sites of high local blood velocity than at sites of low local blood velocity. This induced more tissue heating and larger lesion volumes than ablations at low velocity regions. In contrast, for power-controlled ablation, tissue heating was less at sites of high compared with low local blood velocity for the same RF power setting. This resulted in smaller lesion volumes at sites of low local velocity. Our numerical analyzes showed that during temperature-controlled ablation at 60 degrees C, the lesion volumes at sites above and underneath the mitral valve were comparable when the duration of RF current application was 10 s. When the duration of RF application was extended to 60 s and 120 s, lesion volumes were 33.3% and 49.4% larger above the mitral valve than underneath the mitral valve. Also, with temperature-controlled ablation, tip temperature settings of 70 degrees C or greater were associated with a risk of tissue overheating during long ablations at high local blood velocity sites. In power-controlled ablation (20 W), the lesion volume formed underneath the mitral valve was 165.7% larger than the lesion volume above the mitral valve after 10 s of ablation. We summarized the guidelines for energy application at low and high flow regions.

  20. Radiofrequency ablation of lung metastases close to large vessels during vascular occlusion: preliminary experience.

    Science.gov (United States)

    de Baere, Thierry; Robinson, Joey Marie; Rao, Pramod; Teriitehau, Christophe; Deschamps, Frederic

    2011-06-01

    To report an initial prospective evaluation of the technical feasibility, efficacy, and safety of combining percutaneous temporary balloon occlusion (PBO) of a large pulmonary artery adjacent to a metastatic lung tumor treated with percutaneous radiofrequency (RF) ablation. In six patients, lung RF ablation with a multitined, expandable electrode with simultaneous PBO via femoral access was attempted with the use of digital angiography and multidetector computed tomography (CT). Follow-up imaging was obtained immediately after treatment, at 1-2 days, and at 2, 6, 9, and 12 months; positron emission tomography/CT was performed at 4 months. Metastases targeted measured 17-37 mm (22 ± 8) and were in contact with a pulmonary artery 3-5 mm. Temporary occlusion of the pulmonary arterial branch in contact with the tumor was technically possible in five of six patients. Postablation CT scans obtained within 2 days of the procedure showed ablation zones measuring 37-57 mm (47 ± 8) in their shortest diameter. Three patients developed lung infarction within 1 month after RF ablation, and two had to be readmitted. At 3 months after the procedure, four patients had persistent occlusion of the balloon-occluded vessel. No uptake was demonstrated 4 months after ablation; at 12 months, all tumors showed complete ablation on CT. RF ablation of lung tumors with PBO is a feasible technique, but it induces atelectasia and long-lasting vascular occlusion responsible for a high rate of readmission. The results of this small study warrant careful further exploration of the benefits of the technique, compared with RF ablation without PBO or other methods of ablative therapy. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  1. Advances in radiofrequency ablation of the cerebral cortex in primates using the venous system: Improvements for treating epilepsy with catheter ablation technology.

    Science.gov (United States)

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

    2014-08-01

    Pharmacology frequently fails for the treatment of epilepsy. Although surgical techniques are effective, these procedures are highly invasive. We describe feasibility and efficacy of minimally invasive mapping and ablation for the treatment of epilepsy. Mapping and radiofrequency ablations were performed via the venous system in eleven baboons and three dogs. Mapping in deep cerebral areas was obtained in all animals. High-frequency pacing was able to induce seizure activity of local cerebral tissue in 72% of our attempts. Cerebral activity could be seen during mapping. Ablative lesions were deployed at deep brain sites without steam pops or sudden impedance rise. Histologic analysis showed necrosis at the sites of ablation in all primates. Navigation through the cerebral venous system to map seizure activity is feasible. Radiofrequency energy can be delivered transvenously or transcortically to successfully ablate cortical tissue in this animal model using this innovative approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Considering Angle Selection When Using Ultrasound Electrode Displacement Elastography to Evaluate Radiofrequency Ablation of Tissues

    Directory of Open Access Journals (Sweden)

    Jingjing Xia

    2014-01-01

    Full Text Available Percutaneous radiofrequency ablation (RFA is a minimally invasive treatment to thermally destroy tumors. Ultrasound-based electrode-displacement elastography is an emerging technique for evaluating the region of RFA-induced lesions. The angle between the imaging probe and the RFA electrode can influence electrode-displacement elastography when visualizing the ablation zone. We explored the angle effect on electrode-displacement elastography to measure the ablation zone. Phantoms embedded with meatballs were fabricated and then ablated using an RFA system to simulate RFA-induced lesions. For each phantom, a commercial ultrasound scanner with a 7.5 MHz linear probe was used to acquire raw image data at different angles, ranging from 30° to 90° at increments of 10°, to construct electrode-displacement images and facilitate comparisons with tissue section images. The results revealed that the ablation regions detected using electrode-displacement elastography were highly correlated with those from tissue section images when the angle was between 30° and 60°. However, the boundaries of lesions were difficult to distinguish, when the angle was larger than 60°. The experimental findings suggest that angle selection should be considered to achieve reliable electrode-displacement elastography to describe ablation zones.

  3. Ultrasound-guided percutaneous radiofrequency ablation of liver tumors: How we do it safety and completely

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Woong; Shin, Sang Soo; Heo, Suk Hee; Hong, Jun Hyung; Lim, Hyo Soon; Seon, Hyun Ju; Hur, Young Hoe; Park, Chang Hwan; Jeong, Yong Yeon; Kang, Heoung Keun [Chonnam National University Medical School, Gwangju (Korea, Republic of)

    2015-12-15

    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.

  4. The combined effect of radiofrequency and ethanol ablation in the management of large hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sakr, Ayman A. [Department of Radiation Sciences, Radiology Unit, Medical Research Institute, University of Alexandria, 165 Horreya Avenue, El Hadara, Alexandria (Egypt)]. E-mail: aymansakr12345@hotmail.com; Saleh, Alaa Ahmed [Department of Radiation Sciences, Radiology Unit, Medical Research Institute, University of Alexandria, 165 Horreya Avenue, El Hadara, Alexandria (Egypt); Moeaty, Amr Ali Abdel [Department of Internal Medicine, Faculty of Medicine, University of Alexandria, Alexandria (Egypt); Moeaty, Ali Abdel [Department of Internal Medicine, Faculty of Medicine, University of Alexandria, Alexandria (Egypt)

    2005-06-01

    Only a small percentage of patients with large hepatocellular carcinoma (HCC) may benefit out of surgical resection. Thus, most of these patients are in need of a form of local control, such as ethanol ablation, transarterial chemoembolization (TACE), radiofrequency thermal ablation (RF), or laser induced thermotherapy (LITT). The purpose of this study was to assess the short-term effect of sequential RF and ethanol ablation in the management of large HCC (>5 cm). Our series included 40 patients with large HCC tumors (>5 cm in diameter). We adopted a protocol of overlapping RF applications, followed by repeated ethanol ablation sessions. Our results showed that the volume of tumor coagulative necrosis initially induced by RF has significantly risen after adjuvant ethanol ablation sessions (P < 0.001). Patients who achieved complete tumor necrosis after RF ablation were 52.5% of the series. This percent has jumped to 80% of the series at the end of the protocol. This indicates that such combined protocol is more effective than RF alone. Besides, it is valuable in reducing the number of RF sessions.

  5. No-touch radiofrequency ablation: A comparison of switching bipolar and switching monopolar ablation in Ex Vivo bovine liver

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Won; Lee, Jeong Min; Lee, Sang Min; Hank, Joon Koo [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2017-04-15

    To evaluate the feasibility, efficiency, and safety of no-touch switching bipolar (SB) and switching monopolar (SM) radiofrequency ablation (RFA) using ex vivo bovine livers. A pork loin cube was inserted as a tumor mimicker in the bovine liver block; RFA was performed using the no-touch technique in the SM (group A1; 10 minutes, n = 10, group A2; 15 minutes, n = 10) and SB (group B; 10 minutes, n = 10) modes. The groups were compared based on the creation of confluent necrosis with sufficient safety margins, the dimensions, and distance between the electrode and ablation zone margin (DEM). To evaluate safety, small bowel loops were placed above the liver surface and 30 additional ablations were performed in the same groups. Confluent necroses with sufficient safety margins were created in all specimens. SM RFA created significantly larger volumes of ablation compared to SB RFA (all p < 0.001). The DEM of group B was significantly lower than those of groups A1 and A2 (all p < 0.001). Although thermal injury to the small bowel was noted in 90%, 100%, and 30% of the cases in groups A1, A2, and B, respectively, full depth injury was noted only in 60% of group A2 cases. The no-touch RFA technique is feasible in both the SB and SM modes; however, SB RFA appears to be more advantageous compared to SM RFA in the creation of an ablation zone while avoiding the unnecessary creation of an adjacent parenchymal ablation zone or adjacent small bowel injuries.

  6. Diffusion-weighted imaging during MR-guided radiofrequency ablation of hepatic malignancies: analysis of immediate pre- and post-ablative diffusion characteristics.

    Science.gov (United States)

    Hoffmann, Rüdiger; Rempp, Hansjörg; Schraml, Christina; Schwenzer, Nina; Grözinger, Gerd; Blumenstock, Gunnar; Rothgang, Eva; Pereira, Philippe L; Claussen, Claus D; Clasen, Stephan

    2015-08-01

    Previous studies have shown a benefit of magnetic resonance (MR)-diffusion-weighted imaging (DWI) for follow-up after liver radiofrequency (RF) ablation. However, no data are available concerning acute changes of DWI characteristics immediately after RF ablation. To analyze and compare the MR-diffusion characteristics of pre-interventional hepatic malignancies and the ablation zone during successful MR-guided RF ablation. This retrospective study was conducted in accordance with the guidelines of the local institutional review board. Forty-seven patients with 29 HCC (24 patients) and 30 hepatic metastases (23 patients) underwent MR-guided radiofrequency ablation including DWI before and immediately after ablation (b =  0, 400, 800 s/mm(2)). Two reviewers (A and B) analyzed DWI with focus on detectability of the tumor before ablation and characteristics of the coagulative area after treatment. Mean apparent diffusion coefficient (ADC) was compared between liver, untreated tumor, and hyperintense areas in post-ablative DWI (b = 800 s/mm(2)) with the paired Student's t-test. Pre-ablative: the reviewers classified 19/29 (A) and 23/29 (B) HCC and 25/30 (A and B) metastases as detectable in DWI. Post-ablative: a hyperintense rim surrounding the ablation zone was observed in 28/29 treated HCC and 30/30 treated metastases (A and B). A homogenous hypointense central ablation zone was found in 18/29 (A) and 20/29 (B) treated HCC and 17/30 (A & B) treated metastases in DWI. ADC of the rim was significantly lower than ADC of the liver (P ablation in most cases. A common post-ablative DWI finding is a hyperintense rim with decreased ADC surrounding the ablation zone. © The Foundation Acta Radiologica 2014.

  7. Treatment of hemicrania continua with radiofrequency ablation and long-term follow-up.

    Science.gov (United States)

    Beams, Jennifer L; Kline, Matthew T; Rozen, Todd D

    2015-11-01

    The objective of this research is to describe novel procedural treatments for hemicrania continua that allow patients to remain off indomethacin. Case reports are presented. We describe four distinct patients with indomethacin-responsive hemicrania continua who were unable to discontinue the use of indomethacin without headache recurrence. No other medications were effective for their syndrome. Secondary causes of headache were ruled out in each case. Each patient underwent diagnostic blockade of either the atlanto-axial joint, C2 dorsal root ganglion or sphenopalantine ganglion depending on their clinical examination and presence of cranial autonomic symptoms. A positive response led to a radiofrequency ablation of the C2 ventral ramus, C2 dorsal root ganglion or sphenopalantine ganglion, which provided headache relief in all case patients as complete as indomethacin. Long-term follow-up of these patients has shown that all have remained essentially headache free without the need for indomethacin. One patient has needed repeat radiofrequency procedures with consistent response. Hemicrania continua is defined by its sensitivity to indomethacin but very few patients are able to discontinue the medication without headache recurrence. As the risks of chronic indomethacin use are substantial, alternative treatments are necessary to protect patient health. We are now able to suggest several radiofrequency ablation procedures as effective as indomethacin with long-term follow-up. © International Headache Society 2015.

  8. Cost-effectiveness of radiofrequency catheter ablation for atrial fibrillation.

    Science.gov (United States)

    Chan, Paul S; Vijan, Sandeep; Morady, Fred; Oral, Hakan

    2006-06-20

    We sought to compare the cost-effectiveness of left atrial catheter ablation (LACA), amiodarone, and rate control therapy in the management of atrial fibrillation (AF). Left atrial catheter ablation has been performed to eliminate AF, but its cost-effectiveness is unknown. We developed a decision-analytic model to evaluate the cost-effectiveness of LACA in 55- and 65-year-old cohorts with AF at moderate and low stroke risk. Costs, health utilities, and transition probabilities were derived from published literature and Medicare data. We performed primary threshold analyses to determine the minimum level of LACA efficacy and stroke risk reduction needed to make LACA cost-effective at 50,000 dollars and 100,000 dollars per quality-adjusted life-year (QALY) thresholds. In 65-year-old subjects with AF at moderate stroke risk, relative reduction in stroke risk with an 80% LACA efficacy rate for sinus rhythm restoration would need to be > or =42% and > or =11% to yield incremental cost-effectiveness ratios (ICERs) LACA efficacy rates would require correspondingly lower and higher stroke risk reduction for equivalent ICER thresholds. In the 55-year-old moderate stroke risk cohort, lower LACA efficacy rates or stroke risk reduction would be needed for the same ICER thresholds. In patients at low stroke risk, LACA was unlikely to be cost-effective. The use of LACA may be cost-effective in patients with AF at moderate risk for stroke, but it is not cost-effective in low-risk patients. Our threshold analyses may provide a framework for the design of future clinical trials by providing effect size estimates for LACA efficacy needed.

  9. Modified phased radiofrequency ablation of atrial fibrillation reduces the number of cerebral microembolic signals.

    Science.gov (United States)

    Zellerhoff, Stephan; Ritter, Martin A; Kochhäuser, Simon; Dittrich, Ralf; Köbe, Julia; Milberg, Peter; Korsukewitz, Catharina; Dechering, Dirk G; Pott, Christian; Wasmer, Kristina; Leitz, Patrick; Güner, Fatih; Eckardt, Lars; Mönnig, Gerold

    2014-03-01

    Phased radiofrequency (RF) ablation for atrial fibrillation is associated with an increased number of silent cerebral lesions on magnetic resonance imaging and cerebral microembolic signals (MESs) on transcranial Doppler ultrasound imaging compared with irrigated RF. The increased rate of embolic events may be due to a specific electrical interference of ablation electrodes attributed to the catheter design. The purpose of this study was to elucidate the effect of deactivating the culprit electrodes on cerebral MESs. Twenty-nine consecutive patients (60 ± 11 years, 10 female) underwent their first pulmonary vein isolation using phased RF energy. Electrode pairs 1 or 5 were deactivated to avoid electrical interference between electrodes 1 and 10 ('modified'). Detection of MESs by transcranial Doppler ultrasound was performed throughout the procedure to assess cerebral microembolism. Results were compared with the numbers of MESs in 31 patients ablated using all available electrodes ('conventional') and to 30 patients undergoing irrigated RF ablation of a previous randomized study. Ablation with 'modified' phased RF was associated with a marked decrease in MESs when compared with 'conventional' phased RF (566 ± 332 vs. 1530 ± 980; P ablation (646 ± 449; P = 0.7). Total procedure duration as well as time of RF delivery was comparable between phased RF groups. Both times, however, were significantly shorter compared with the irrigated RF group (123 ± 28 vs. 195 ± 38; 15 ± 4 vs. 30 ± 9; P ablation impulses, supporting the significance of electrical interference between ablation electrodes 1 and 10. Deactivation of electrode pairs 1 or 5 might increase the safety of this approach without an increase in procedure duration or RF delivery time.

  10. Endoscopic Ultrasound-Guided Radiofrequency Ablation (EUS-RFA of the Pancreas in a Porcine Model

    Directory of Open Access Journals (Sweden)

    Monica Gaidhane

    2012-01-01

    Full Text Available Backgrounds. Limited effective palliative treatments exist for pancreatic cancer which includes surgery or chemotherapy. Radiofrequency ablation (RFA uses high frequency alternating current to ablate diseased tissue and has been used to treat various tumors. In this study, we evaluated a prototype probe adjusted to the EUS-needle to perform EUS-RFA to permit coagulative necrosis in the pancreas. Methods. Five Yucatan pigs underwent EUS-guided radiofrequency ablation of the head of their pancreas. Using an EUS-needle, RFA was applied with 6 mm and then 10 mm of the probe exposed at specific wattage for preset durations. Results. Only one pig showed moderate levels of pancreatitis (20% proximal pancreatitis. The other animals showed much lower areas of tissue damage. In 3 of the 5 pigs, the proximal pancreas showed greater levels of tissue injury than the distal pancreas, consistent with the proximity of the tissue to the procedure site. In 1 pig, both proximal and distal pancreas showed minimal pancreatitis (1%. There was minimal evidence of fat necrosis in intra-pancreatic and/or extra-pancreatic adipose tissue. Conclusion. EUS-guided RFA of the pancreatic head with the monopolar probe through a 19-gauge needle was well tolerated in 5 Yucatan pigs and with minimal amount of pancreatitis.

  11. Radiofrequency ablation of rabbit liver. Correlation between dual CT findings and pathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Tsuda, Masashi [National Sendai Hospital (Japan); Rikimaru, Yuya; Saito, Haruo; Ishibashi, Tadashi; Takahashi, Shyoki; Miyachi, Hideo; Yamada, Syogo [Tohoku Univ., Sendai (Japan). School of Medicine

    2002-12-01

    The purpose of this study was to present the time-related imaging findings and correlative pathologic findings of radiofrequency pulse-irradiated regions of the liver. Radiofrequency (RF) ablation was performed in 22 rabbit livers with 15-gauge RF probes inserted percutaneously. Regions were imaged with dual-phase CT at 3 days (n=6), 2 weeks (n=6), 4 weeks (n=6), and 12 weeks (n=4) after RF ablation. At 3 days, the regions showed a two-zone structure on plain CT and peripheral enhancement. The regions presented a three-zone structure on pathological study. Hepatocytes appeared as acidophilic bodies, and nuclei were pyknotic at the inner necrotic zone. The middle whitish zone showed enlarged sinusoids. The marginal zone was a regenerative band. At 2 weeks, the two-zone structure was obscured on unenhanced CT. The region showed a two-zone structure on pathological study. At the inner zone, acidophilic degeneration had progressed, however, cell structure remained. The marginal zone showed fibrous tissue bundles. At 12 weeks, the region was obscured on plain CT. Nuclei and cell structures had disappeared almost completely at the inner zone. Collagen fiber had replaced the marginal zone. Zone structural CT findings reflect the pathological findings and time-related changes after RF ablation. Peripheral enhancement in the arterial phase reflects the granulation tissue layer, and its time-related decrease reflects replacement by fibrous tissue. (author)

  12. Assessment of ablative margin after radiofrequency ablation for hepatocellular carcinoma; comparison between magnetic resonance imaging with ferucarbotran and enhanced CT with iodized oil deposition.

    Science.gov (United States)

    Koda, Masahiko; Tokunaga, Shiho; Fujise, Yuki; Kato, Jun; Matono, Tomomitsu; Sugihara, Takaaki; Nagahara, Takakazu; Ueki, Masaru; Murawaki, Yoshikazu; Kakite, Suguru; Yamashita, Eijiro

    2012-07-01

    Our aim was to investigate whether magnetic resonance imaging (MRI) with ferucarbotran administered prior to radiofrequency ablation could accurately assess ablative margin when compared with enhanced computed tomography (CT) with iodized oil marking. We enrolled 27 patients with 32 hepatocellular carcinomas in which iodized oil deposits were visible throughout the nodule after transcatheter arterial chemoembolization. For these nodules, radiofrequency ablation was performed after ferucarbotran administration. We then performed T2-weighted MRI after 1 week and enhanced CT after 1 month. T2-weighted MRI demonstrated the ablative margin as a low-intensity rim. We classified the margin into three grades; margin (+): high-intensity area with a continuous low-intensity rim; margin zero: high-intensity area with a discontinuous low-intensity rim; and margin (-): high-intensity area extending beyond the low-intensity rim. In 28 (86%) of 32 nodules, there was agreement between MRI and CT. The overall agreement between for the two modalities in the assessment of ablative margin was good (κ=0.759, 95% confidence interval: 0.480-1.000, pablative margins on MRI were underestimated by one grade compared with CT. MRI using ferucarbotran is less invasive and allows earlier assessment than CT. The MRI technique performed similarly to enhanced CT with iodized oil marking in evaluating the ablative margin after radiofrequency ablation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  13. Performance of a novel dual-electrode bipolar radiofrequency ablation device: a chronic porcine study.

    Science.gov (United States)

    Voeller, Rochus K; Zierer, Andreas; Schuessler, Richard B; Damiano, Ralph J

    2011-01-01

    : Over recent years, a variety of energy sources, including bipolar radiofrequency, have been used to replace the traditional incisions of the Cox-Maze procedure for the surgical treatment of atrial fibrillation (AF). The purpose of this study was to evaluate the safety and efficacy of a novel dual-electrode bipolar radiofrequency ablation device Synergy (Atricure, Inc., Cincinnati, OH USA) for AF in a chronic porcine model. : Six domestic pigs underwent a modified Cox-Maze IV procedure without cardiopulmonary bypass using the Synergy device. Animals survived for 30 days. Each pig then underwent induction of AF and was killed to remove the heart en bloc for histologic assessment. Each ablation line was dissected perpendicularly at 5-mm intervals to assess the lesion width, depth, and transmurality. : All animals survived the operation. Electrical isolation of the left atrial appendage and the pulmonary veins were documented by pacing acutely and at 30 days after the operation in all six animals. All animals failed to be induced in AF at 30 days. There was no gross evidence of intra-atrial thrombus formation or stricture of the pulmonary veins. All ablations (n = 209) examined were discrete, linear, and transmural, with a mean lesion width of 3.0 ± 0.7 mm and a mean lesion depth of 5.4 ± 3.3 mm. The mean ablation time was 16.3 ± 4.4 seconds, with a mean total energy delivery of 238 ± 170 J. : The Atricure Synergy was able to create reliable chronic transmural lesions of the modified Cox-Maze IV procedure on a porcine beating heart without cardiopulmonary bypass. The ablation lines were significantly wider when compared with its predecessor, the Isolator II.

  14. Efficacy of Bipolar Radiofrequency Endometrial Ablation vs Thermal Balloon Ablation for the Management of Menorrhagia: A Population-Based Cohort

    Science.gov (United States)

    El-Nashar, Sherif A.; Hopkins, Matthew R.; Creedon, Douglas J.; Cliby, William A.; Famuyide, Abimbola O.

    2009-01-01

    Study Objective: To compare the efficacy of bipolar radiofrequency ablation (RFA) and thermal balloon ablation (TBA) using treatment failure and postprocedure amenorrhea as outcome measures. Design: A population-based cohort study (Canadian Task Force classification II-2). Setting: Two medical centers in the Upper Midwest. Patients: Using the medical records linkage system of the Rochester Epidemiology Project, we identified 455 residents of Olmsted County, Minnesota, who underwent global endometrial ablation for menorrhagia from January 1, 1998, through December 31, 2005. Amenorrhea was defined as complete cessation of menstruation that started immediately after ablation and lasted at least 12 months. Treatment failure was defined as re-ablation or hysterectomy for persistent bleeding or pain. Time to treatment failure for each procedure was compared using Kaplan-Meier plots. Relevant clinical data and complications were abstracted from medical records. Risk adjustments were performed using Cox and logistic regression models. Interventions: RFA (n=255) and TBA (n=200). Measurements and Main Results: Mean (SD) patient age was 43.3 (5.5) years, and median follow-up was 2.2 years. The 3-year cumulative failure rate was 9% (95% confidence interval [CI], 5%-16%) for RFA and 12% (95% CI, 7%-16%) for TBA (P=.26). The difference remained nonsignificant after adjusting for known predictors of treatment failure such as age, parity, pretreatment dysmenorrhea, and tubal ligation (adjusted hazard ratio, 0.7; 95% CI, 0.4-1.4; P=.31). However, women had significantly higher amenorrhea rates after RFA when compared with TBA (32% vs 14%, Pmenorrhagia in a population-based cohort. However, women who underwent RFA were 3 times more likely to have postprocedure amenorrhea. PMID:19896595

  15. Three-dimensional comparison of interventional MR radiofrequency ablation images with tissue response.

    Science.gov (United States)

    Breen, Michael S; Lazebnik, Roee S; Nour, Sherif G; Lewin, Jonathan S; Wilson, David L

    2004-01-01

    Solid tumors are being treated using radiofrequency (RF) ablation under interventional magnetic resonance imaging (MRI) guidance. We are investigating the ability of MRI to monitor ablation treatments by comparing MR images of thermal lesions to histologically assayed tissue damage. An open MRI system was used to guide an ablation electrode into five rabbit thigh muscles and acquire post-ablation MR image volumes. We developed a methodology using a 3D computer registration to make spatial correlations. After MR and histology images were registered with an accuracy of 1.32+/-0.39 mm (mean+/-SD), a boundary of necrosis identified in the histology was compared with the outer boundary of the hyperintense region in MR images. For 14 T2-weighted MR images, the absolute distance between boundaries was 0.96+/-0.34 mm (mean+/-SD). Since the small discrepancy between boundaries is comparable to our registration accuracy, the boundaries may match exactly. Similar correlations to histology were obtained with a deformable model segmentation method. This is good evidence that MR thermal lesion images can be used during RF ablation treatments to accurately localize the zone of necrosis at the lesion margin.

  16. Radiofrequency ablation of pancreas and optimal cooling of peripancreatic tissue in an ex-vivo porcine model

    Directory of Open Access Journals (Sweden)

    Michal Crha

    2011-01-01

    Full Text Available Radiofrequency ablation is a possible palliative treatment for patients suffering from pancreatic neoplasia. However, radiofrequency-induced damage to the peripancreatic tissues during pancreatic ablation might cause fatal complications. The aim of this experimental ex vivo study on pigs was to verify ablation protocols and evaluate whether or not the cooling of peripancereatic tissues during pancreatic ablation has any benefit for their protection against thermal injury. Radiofrequency ablation was performed on 52 pancreatic specimens obtained from pigs. During each pancreatic ablation, continuous measurements of the temperature in the portal vein and duodenal lumen were performed. Peripancreatic tissues were either not cooled or were cooled by being submerged in 14 °C water, or by a perfusion of the portal vein and duodenum with 14 °C saline. The effects of variation in target temperature of the ablated area (90 °C and 100 °C, duration of ablation (5 and 10 min and the effect of peripancreatic tissues cooling were studied. We proved that optimal radiofrequency ablation of the porcine pancreas can be reached with the temperature of 90  °C for 5 min in the ablated area. The perfusion of the duodenal and portal vein by 14 °C saline was found to be the most effective cooling method for minimizing damage to the walls. Continuous measurement of temperatures in peripancreatic tissues will provide useful feedback to assist in their protection against thermal injury. This therapy could be used in the treatment of pancreatic tumours.

  17. Pulsed Radiofrequency Ablation of Pudendal Nerve for Treatment of a Case of Refractory Pelvic Pain.

    Science.gov (United States)

    Petrov-Kondratov, Vadim; Chhabra, Avneesh; Jones, Stephanie

    2017-03-01

    Pudendal neuralgia (PN) is a result of pudendal nerve entrapment or injury, also called "Alcock syndrome." Pain that develops is often chronic, and at times debilitating. If conservative measures fail, invasive treatment modalities can be considered. The goal of this case report is to add to a small body of literature that a pulsed radiofrequency (PRF) ablation can be effectively used to treat PN and to show that high resolution MR neurography imaging can be used to detect pudendal neuropathy. We present a case of a 51-year-old woman with 5 years of worsening right groin and vulva pain. Various medication trials only lead to limited improvement in pain. The first diagnostic right pudendal nerve block was done using 3 mL of 0.25% bupivacaine with 6mg of betamethasone using a transgluteal technique and a target of the right ischial spine; this procedure resulted in ~8 hours of > 50% pain relief. The patient was then referred for MR neurography of the lumbosacral plexus. This study revealed increased signal of the right pudendal nerve at the ischial spine and in the pudendal canal, findings consistent with the clinical picture of PN. Six weeks after the initial block, the patient underwent a second right transgluteal pudendal nerve block, utilizing 3 mL of 0.25% bupivacaine with 40 mg of triamcinolone acetonide; this procedure resulted in ~8 hours of 100% pain relief. Satisfied with these results the patient decided to undergo pudendal nerve PRF ablation for possible long-term relief. For this therapeutic procedure, a right transgluteal approach was again utilized. PRF ablation was performed for 240 seconds at 42° Celsius. Following this ablation the patient reported at least 6 weeks of significant (> 50%) pain relief. In this paper we presented a case of successful treatment of PN with PRF ablation and detection of pudendal neuropathy on MR neurography. We believe that transgluteal PRF ablation for PN might be an effective, minimally invasive option for those

  18. A measure to assess the ablative margin using 3D-CT image fusion after radiofrequency ablation of hepatocellular carcinoma

    Science.gov (United States)

    Tang, Hui; Tang, Yunqiang; Hong, Jian; Chen, Tiejun; Mai, Cong; Jiang, Peng

    2015-01-01

    Objectives To examine the feasibility of three-dimensional computed tomography (3D-CT) image fusion in facilitating assessment of the ablative margin (AM) after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). Methods This study involved 75 patients with solitary HCC who underwent RFA. The AM was evaluated using 3D-CT image fusion. All cases were categorized into two groups based on the extent of the AM: in Group A, sufficient AM was obtained, which was greater than or equal to 5 mm; in Group B, the lesion was also ablated successfully, but a 5 mm AM was not obtained. Results 3D-CT Image Fusion was performed on 36 and 39 patients in Group A and Group B, respectively. The 1, 3, 5 year RFS was 87.6%, 63.2%, 50.6% for Group A, and 77.2%, 51.5%, 35.6% for Group B, respectively (P = 0.042); the corresponding OS was 94.3%, 73.8%, 64.6%, and 86.2%, 60.5%, 47.6%, respectively (P = 0.046). Multivariate analysis showed that the AM (P = 0.048, HR = 2.15, 95% CI 1.01–4.60) and Pre-NLR were independent prognostic factors for PFS. Conclusions 3D-CT image fusion is a feasible and useful method to evaluate the AM after RFA of HCC. PMID:25346478

  19. Treatment of osteoid osteoma using CT-guided radiofrequency ablation versus MR-guided laser ablation: A cost comparison

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, M.H., E-mail: martin.maurer@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany); Gebauer, B., E-mail: bernhard.gebauer@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany); Wieners, G., E-mail: gero.wieners@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany); De Bucourt, M., E-mail: maximilian.de-bucourt@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany); Renz, D.M., E-mail: diane.renz@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany); Hamm, B., E-mail: bernd.hamm@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany); Streitparth, F., E-mail: florian.streitparth@charite.de [Charite - Universitaetsmedizin Berlin, Department of Radiology, Augustenburger Platz 1, 13353 Berlin (Germany)

    2012-11-15

    Objective: To compare the costs of CT-guided radiofrequency ablation (RFA) and MR-guided laser ablation (LA) for minimally invasive percutaneous treatment of osteoid osteoma. Materials and methods: Between November 2005 and October 2011, 20 patients (14 males, 6 females, mean age 20.3 {+-} 9.1 years) underwent CT-guided RFA and 24 patients (18 males, 6 females; mean age, 23.8 {+-} 13.8 years) MR-guided LA (open 1.0 Tesla, Panorama HFO, Philips, Best, Netherlands) for osteoid osteoma diagnosed on the basis of clinical presentation and imaging findings. Prorated costs of equipment use (purchase, depreciation, and maintenance), staff costs, and expenditure for disposables were identified for CT-guided RFA and MR-guided LA procedures. Results: The average total costs per patient were EUR 1762 for CT-guided RFA and EUR 1417 for MR-guided LA. These were (RFA/LA) EUR 92/260 for equipment use, EUR 149/208 for staff, and EUR 870/300 for disposables. Conclusion: MR-guided LA is less expensive than CT-guided RFA for minimally invasive percutaneous ablation of osteoid osteoma. The higher costs of RFA are primarily due to the higher price of the disposable RFA probes.

  20. CT-guided radiofrequency ablation of osteoid osteoma using a novel battery-powered drill

    Energy Technology Data Exchange (ETDEWEB)

    Schnapauff, Dirk; Streitparth, Florian; Wieners, Gero; Collettini, Federico; Hamm, Bernd; Gebauer, Bernhard [Charite Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Joehrens, Korinna [Charite Universitaetsmedizin Berlin, Department of Pathology, Berlin (Germany)

    2015-05-01

    To evaluate the use of a novel battery-powered drill, enabling specimen requirement while drilling, in radiofrequency ablation of osteoid osteoma as an alternative to conventional orthopedic drills. Between 2009 and 2013, altogether 33 patients underwent CT-guided radiofrequency ablation of an osteoid osteoma at our institution. To access the nidus of the clinically and radiologically suspected osteoid osteoma, a channel was drilled using the OnControl Bone Marrow Biopsy System (OBM, Arrow OnControl, Teleflex, Shavano Park, TX, USA) and a biopsy was taken. Procedure time (i.e., drilling including local anesthesia), amount of scans (i.e., single-shot fluoroscopy), radiation exposure, and the results of biopsy were investigated and compared retrospectively to a classical approach using either a manual bone biopsy system or a conventional orthopedic drill (n = 10) after ethical review board approval. Drilling the tract into the nidus was performed without problems in 22 of the 23 OBM cases. Median procedure time was 7 min compared to 13 min using the classical approach (p < 0.001). Median amount CT scans, performed to control correct positioning of the drill was comparable with 26 compared to 24.5 (p = NS) scans. Histologically, the diagnosis of osteoid osteomas could be determined in all 17 cases where a biopsy was taken. Radiofrequency ablation could be performed without problems in any case. The use of the battery-powered drill was feasible and facilitated the access to the osteoid osteoma's nidus offering the possibility to extract a specimen in the same step. (orig.)

  1. Efficacy of percutaneous intraductal radiofrequency ablation combined with biliary stenting in treatment of malignant biliary obstruction

    Directory of Open Access Journals (Sweden)

    ZHANG Kai

    2015-05-01

    Full Text Available ObjectiveTo investigate the safety and feasibility of percutaneous intraductal radiofrequency ablation (palliative therapy in the treatment of malignant obstructive jaundice. MethodsThis study included 20 patients with unresectable malignant obstructive jaundice, who were treated in the First Affiliated Hospital of Zhengzhou University from January 2013 to March 2014. Nine of them (test group underwent percutaneous intraductal radiofrequency ablation plus metallic biliary stent placement. The other 11 similar cases (control group underwent metallic biliary stent placement alone after successful percutaneous transhepatic cholangiography. Operative complications and remission of jaundice were observed, and the stent patency after at 3 and 6 months after operation was evaluated and compared between the two groups. ResultsAll patients were followed completely by outpatient or telephone. The stent patency rate at 3 months after operation was 9/9 in the test group and 8/11 in the control group (χ2=2.888, P=0.218, and the stent patency rates at 6 months were 7/8 and 3/11, respectively (χ2=6.739, P=0.02. During follow-up, one case in the test group died of gastrointestinal bleeding at 113 d after operation; one case in the control group died of liver failure at 57 d after operation and one case died of disseminated intravascular coagulation at 142 d. ConclusionPercutaneous intraductal radiofrequency ablation is safe and feasible in the treatment of malignant biliary obstruction, and the preliminary efficacy in prolonging the patency of self-expanding metallic stent is satisfactory. However, this therapy needs to be further verified via large-sample randomized controlled studies.

  2. The cost-effectiveness of radiofrequency catheter ablation as first-line treatment for paroxysmal atrial fibrillation

    DEFF Research Database (Denmark)

    Aronsson, Mattias; Walfridsson, Håkan; Janzon, Magnus

    2014-01-01

    AIM: The aim of this prospective substudy was to estimate the cost-effectiveness of treating paroxysmal atrial fibrillation (AF) with radiofrequency catheter ablation (RFA) compared with antiarrhythmic drugs (AADs) as first-line treatment. METHODS AND RESULTS: A decision-analytic Markov model......, based on MANTRA-PAF (Medical Antiarrhythmic Treatment or Radiofrequency Ablation in Paroxysmal Atrial Fibrillation) study data, was developed to study long-term effects and costs of RFA compared with AADs as first-line treatment. Positive clinical effects were found in the overall population, a gain......-effectiveness ratio of €3434/QALY in ≤50-year-old patients respectively €108 937/QALY in >50-year-old patients. CONCLUSION: Radiofrequency catheter ablation as first-line treatment is a cost-effective strategy for younger patients with paroxysmal AF. However, the cost-effectiveness of using RFA as first-line therapy...

  3. Computational modeling of radiofrequency ablation: evaluation on ex vivo data using ultrasound monitoring

    Science.gov (United States)

    Audigier, Chloé; Kim, Younsu; Dillow, Austin; Boctor, Emad M.

    2017-03-01

    Radiofrequency ablation (RFA) is the most widely used minimally invasive ablative therapy for liver cancer, but it is challenged by a lack of patient-specific monitoring. Inter-patient tissue variability and the presence of blood vessels make the prediction of the RFA difficult. A monitoring tool which can be personalized for a given patient during the intervention would be helpful to achieve a complete tumor ablation. However, the clinicians do not have access to such a tool, which results in incomplete treatment and a large number of recurrences. Computational models can simulate the phenomena and mechanisms governing this therapy. The temperature evolution as well as the resulted ablation can be modeled. When combined together with intraoperative measurements, computational modeling becomes an accurate and powerful tool to gain quantitative understanding and to enable improvements in the ongoing clinical settings. This paper shows how computational models of RFA can be evaluated using intra-operative measurements. First, simulations are used to demonstrate the feasibility of the method, which is then evaluated on two ex vivo datasets. RFA is simulated on a simplified geometry to generate realistic longitudinal temperature maps and the resulted necrosis. Computed temperatures are compared with the temperature evolution recorded using thermometers, and with temperatures monitored by ultrasound (US) in a 2D plane containing the ablation tip. Two ablations are performed on two cadaveric bovine livers, and we achieve error of 2.2 °C on average between the computed and the thermistors temperature and 1.4 °C and 2.7 °C on average between the temperature computed and monitored by US during the ablation at two different time points (t = 240 s and t = 900 s).

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

    Directory of Open Access Journals (Sweden)

    Chinmoy Roy

    2014-01-01

    Full Text Available 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.

  5. Pulsed radiofrequency ablation for treatment of severe pain after shoulder arthroplasty (case report

    Directory of Open Access Journals (Sweden)

    D. V. Zabolotsky

    2015-01-01

    Full Text Available A case of refractory neuropathic pain syndrome in patient who underwent monopolar shoulder replacement is presented. The patient had right lung tumor metastasis in the right humeral head. Severe neuropathic pain syndrome, not responding to 6-months conservative treatment, developed in post-operative period. Pulsed radiofrequency ablation of C4-C6 nerve roots via interscalene access was performed. The procedure allowed the patient to stop taking painkillers and improved his quality of life. The patient was monitored for 2 months.

  6. Prevention and treatment of complications after radiofrequency ablation for hepatic tumors in high-risk locations

    Directory of Open Access Journals (Sweden)

    SONG Li

    2017-04-01

    Full Text Available Percutaneous radiofrequency ablation (RFA has been widely used in the treatment of malignant hepatic tumors and has achieved satisfactory effects. Complications after RFA have been taken seriously and the risk of the development of complications is closely associated with tumor location. It is a great challenge for physicians to perform RFA for hepatic tumors in high-risk locations due to related difficulties and risks. This article reviews the complications after RFA for hepatic tumors in high-risk locations and analyzes related control strategies.

  7. Tumor lysis syndrome following endoscopic radiofrequency interstitial thermal ablation of colorectal liver metastases.

    LENUS (Irish Health Repository)

    Barry, B D

    2012-02-03

    Radiofrequency interstitial thermal ablation (RITA) provides a palliative option for patients suffering from metastatic liver disease. This procedure can be performed using a laparoscopic approach with laparoscopic ultrasound used to position the RITA probe. We describe a case of laparoscopic RITA performed for colorectal liver metastasis that was complicated by tumor lysis syndrome (TLS) following treatment. We consider RITA to be a safe procedure, as supported by the literature, but where intracorporal tumor lysis is the treatment goal we believe that the systemic release of tumor products can overwhelm the excretory capacity; therefore, TLS is an inevitable consequence in some patients.

  8. Donor Kidney With Renal Cell Carcinoma Successfully Treated With Radiofrequency Ablation

    DEFF Research Database (Denmark)

    Christensen, S F; Hansen, Jesper Melchior

    2015-01-01

    BACKGROUND: The risk of donor-transmitted cancer is evident. CASE REPORT: We report the case of a 69-year-old woman who was transplanted with a kidney from a deceased donor. Four days after transplantation a routine ultrasound scan revealed a 3-cm tumor in the middle-upper pole of the allograft....... A biopsy showed the tumor to be papillary renal cell carcinoma. The patient was treated with radiofrequency ablation. This procedure was complicated by the development of a cutaneous fistula and open surgery was done with resection of an area of necrosis in the kidney and of the fistula. The maintenance...

  9. Percutaneous radiofrequency thermal ablation of lung VX2 tumors in a rabbit model: evaluation with helical CT findings for the complete and partal ablation

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Gong Yong; Han, Young Min; Lim, Yeong Su; Jang, Kyu Yun; Lee, Sang Yong; Chung, Gyung Ho [School of Medicine, Chonbuk National Univ., Chonju (Korea, Republic of)

    2004-05-01

    To evaluate the radiologic findings for complete and partial ablation after percutaneous CT-guided transthoracic radiofrequency ablation (RFA) of lung VX2 tumor implanted in rabbits. Thirteen rabbits with successfully implanted lung VX2 were used. Three rabbits as controls did not receive RFA while the other ten rabbits underwent RFA; 5 complete and 5 partial. RFA was performed using an internally cooled, 17-gauge electrode (Radionics, Burlington, MA) with a 1-cm active tip under CT guidance. Postprocedural CT was performed within 3 days, and we analyzed the ablated size, enhancement pattern, shape, margin, and complications of the complete and partial ablation groups. Rabbits were sacrificed after postprocedural CT with an overdose of ketamine, and pathologic findings of the ablated groups were compared with those of the control group. The size of the ablated lesions and the enhancement pattern differed between the completely and partially ablated groups on chest CT. The size of the ablated lesions was increased by 47.1% in the completely ablated group and by 2.1% in the partially ablated group. In the completely ablated group, VX2 tumor showed absolutely no enhancement, whereas only ablated pulmonary parenchyma outside VX2 showed mild enhancement on enhanced CT. In the partial ablated group, a part of VX2 became strongly enhanced on enhanced CT. On microscopic examination, the completely ablated group demonstrated that a viable tumor cell was not visible. In the partially ablated group, however, a viable tumor cell within the surrounding fibrous capsule on the peripheral area of the VX2 was observed. The important CT findings for evaluation of complete and partial RFA are the ablated size and enhancement pattern of the ablated lesion.

  10. Is radiofrequency ablation or stereotactic ablative radiotherapy the best treatment for radically treatable primary lung cancer unfit for surgery?

    Science.gov (United States)

    Renaud, Stéphane; Falcoz, Pierre-Emmanuel; Olland, Anne; Massard, Gilbert

    2013-01-01

    A best evidence topic was constructed according to a structured protocol. The question addressed was whether radiofrequency (RF) offers better results than stereotactic ablative therapy in patients suffering from primary non-small-cell lung cancer (NSCLC) unfit for surgery. Of the 90 papers found using a report search for RF, 5 represented the best evidence to answer this clinical question. Concerning stereotactic ablative therapy, of the 112 papers found, 10 represented the best evidence to answer this clinical question. A manual search of the reference lists permitted us to include seven more articles. The authors, journal, date, country of publication, study type, group studied, relevant outcomes and results of these papers are given. We conclude that, on the whole, the 23 retrieved studies clearly support the use of stereotactic ablative therapy rather than RF in patients suffering from primary NSCLC unfit for surgery. Indeed, stereotactic ablative therapy offered a 5-year local control rate varying between 83 and 89.5%, whereas the local control rate after RF ranges from 58 to 68%, with a short follow-up of ∼18 months. Furthermore, both overall survival and cancer-specific survival were better with stereotactic ablative therapy, with a 3-year overall survival ranging from 38 to 84.7% and the 3-year cancer-specific survival from 64 to 88%, whereas the 3-year OS, only reported in two studies, ranged from 47 to 74% for RF. Moreover, the post-interventional morbidity was superior for RF ranging from 33 to 100% (mainly composed by pneumothorax), whereas radiation pneumonitis and rib fracture, ranging, respectively, from 3 to 38% and 1.6 to 4%, were the primary complications following stereotactic ablative therapy. Hence, the current evidence shows that stereotactic ablative therapy is a safe and effective procedure and should be proposed first to patients suffering from primary NSCLC unfit for surgery. However, the published evidence is quite limited, mainly

  11. Radiofrequency thermal ablation of hepatocellular carcinoma: using contrast-enhanced harmonic power doppler sonography to assess treatment outcome.

    Science.gov (United States)

    Cioni, D; Lencioni, R; Rossi, S; Garbagnati, F; Donati, F; Crocetti, L; Bartolozzi, C

    2001-10-01

    We evaluated the accuracy of contrast-enhanced harmonic power Doppler sonography in assessing the outcome of radiofrequency thermal ablation of hepatocellular carcinoma. Fifty patients with 65 hepatocellular carcinoma nodules (1-5 cm in diameter; mean diameter, 2.5 cm) were studied using unenhanced and contrast-enhanced harmonic power Doppler sonography before and after IV administration of a microbubble contrast agent. The examinations were repeated after treatment of the tumors with radiofrequency ablation. Findings of the Doppler studies were compared with those of dual-phase helical CT, which were used as points of reference for assessing treatment outcome. Before radiofrequency treatment, intratumoral blood flow was revealed by unenhanced power Doppler sonography in 48 (74%) of 65 hepatocellular carcinoma nodules. After injection of the contrast agent, intratumoral enhancement was observed in 61 (94%) of 65 hepatocellular carcinomas (p enhancement on power Doppler sonograms. In nine of the 10 lesions that showed a residual viable tumor on helical CT scans, persistent intratumoral enhancement-matching the enhancing areas on helical CT images-was revealed by power Doppler sonography. These nine hepatocellular carcinomas were subjected to repeated radiofrequency thermal ablation with the guidance of contrast-enhanced power Doppler sonography. Complete necrosis was seen after the second treatment session in six of the nine lesions. Contrast-enhanced harmonic power Doppler sonography is an accurate technique for assessing the outcome of radiofrequency thermal ablation of hepatocellular carcinoma and may be useful in guiding additional treatment in patients with incomplete response to initial efforts.

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

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Il [Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul 03722 (Korea, Republic of); Kim, Il Jung [Department of Radiology, Bucheon St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Bucheon 14647 (Korea, Republic of); Lee, Shin Jae [Department of Radiology, CHA Bundang Medical Center, CHA University, Seongnam 13496 (Korea, Republic of); Shin, Min Woo; Shin, Won Sun; Chung, Yong Eun; Kim, Gyoung Min; Kim, Man Deuk; Won, Jong Yun; Lee, Do Yun [Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul 03722 (Korea, Republic of); Choi, Jin Sub [Department of Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul 03722 (Korea, Republic of); Han, Kwang-Hyub [Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722 (Korea, Republic of)

    2016-11-01

    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. 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. 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. 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.

  13. Angled cool-tip electrode for radiofrequency ablation of small superficial subcapsular tumors in the liver: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Il; Shin, Min Woo; Shin, Won Seon [Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); and others

    2016-09-15

    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. 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. 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. 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.

  14. Role of percutaneous computed tomography-guided radiofrequency ablation in treatment of osteoid osteoma

    Directory of Open Access Journals (Sweden)

    Ajay R Upadhyay

    2017-01-01

    Full Text Available Aim: The aim of the study was to evaluate efficacy of percutaneous computed tomography (CT-guided radiofrequency ablation (RFA of nidus in osteoid osteoma (OO. Materials and Methods: RFA was performed on fifty patients with clinically and radiologically diagnosed OO. RFA was done in the department of radio-diagnosis in our institute (a tertiary care providing institute in Ahmedabad, Western India. Ablation was performed by putting at an electrode tip (3–5 mm into nidus under CT guidance with targeted temperature of 90°C for 3 min. Results: All procedures were technically successful. No immediate major or minor complications were observed. Complete clinical success was achieved in 46 patients. Only four patients required second intervention. Conclusion: Our experience indicates a 98% success rate. No major complications were noted.

  15. Update on the role of ultrasound guided radiofrequency ablation for thyroid nodule treatment

    DEFF Research Database (Denmark)

    Radzina, Maija; Cantisani, Vito; Rauda, Madara

    2017-01-01

    with other ablation techniques has been provided as well. US guided Radiofrequency ablation has been proved to be effective and safe in cases of benign thyroid nodules and a promising treatment method alternative to surgery for patients with recurrent papillary thyroid cancer. It's major role lies......Thyroid nodules can be frequently detected in general population, most of them are benign, however malignant cases are rising in the past decades. Ultrasound (US) is the most common imaging modality to assess thyroid nodular lesions, plan patient work-up and guide minimally invasive treatment...... in significant reduction of thyroid nodule mean volume and improvement of the patient symptoms. However, future multicenter studies are warranted to better clarify the multi-parametric patient selection criteria and evaluate RFA technique efficacy, advantages and limitations in the variety of thyroid nodular...

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

    Science.gov (United States)

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

    2015-01-01

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

  17. Epicardial radiofrequency ablation for left ventricular aneurysm related ventricular arrhythmias during off-pump coronary artery bypass surgery.

    Science.gov (United States)

    Yu, Yang; Gao, Ming-Xin; Li, Hai-Tao; Zhang, Fan; Gu, Cheng-Xiong

    2012-11-01

    Left ventricular aneurysm (LVA) is one of the serious complications after acute myocardial infarction. We attempted to evaluate the preliminary efficacy of LVA repair combined with epicardial radiofrequency ablation for ventricular arrhythmia during off-pump coronary artery bypass grafting (OPCAB). From June 2009 to April 2011, 31 patients with LVA had angina symptoms and ventricular arrhythmia. In all patients, circular and cross-shaped radiofrequency epicardial ablations were performed using unipolar ablation pen along the border between the aneurysm wall and normal cardiac tissue and in the central zone of the aneurysms, followed by a linear placation of ventricular aneurysms on beating heart. All the patients showed complete recovery. The average number of grafted vessels was 2.7 ± 1.3. Intraoperative examinations revealed that the ventricular arrhythmia was effectively controlled by radiofrequency ablation. All cases had been followed up for one year. Holter monitoring revealed a significant reduction in ventricular arrhythmias (P aneurysm and preoperative malignant arrhythmia, aneurysm repair plus epicardial radiofrequency ablation in OPCAB was found to be an effective and feasible therapeutic technique. However, medium- to long-term therapeutic efficacy of this method remains to be determined by future studies and observations.

  18. Radiofrequency and microwave tumor ablation in patients with implanted cardiac devices: Is it safe?

    Energy Technology Data Exchange (ETDEWEB)

    Skonieczki, Brendan D., E-mail: bskonieczki@lifespan.org [Department of Diagnostic Imaging, Warren Alpert Medical School of Brown University/Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 (United States); Wells, Catherine, E-mail: cwells1@bidmc.harvard.edu [Department of Radiology, Harvard Medical School/Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States); Wasser, Elliot J., E-mail: ewasser@lifespan.org [Department of Diagnostic Imaging, Warren Alpert Medical School of Brown University/Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 (United States); Dupuy, Damian E., E-mail: ddupuy@lifespan.org [Department of Diagnostic Imaging, Warren Alpert Medical School of Brown University/Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 (United States)

    2011-09-15

    Purpose: To identify malfunction of implanted cardiac devices during or after thermal ablation of tumors in lung, kidney, liver or bone, using radiofrequency (RF) or microwave (MW) energy. Materials and methods: After providing written consent, 19 patients (15 men and 4 women; mean age 78 years) with pacemakers or pacemaker/defibrillators underwent 22 CT image-guided percutaneous RF or MW ablation of a variety of tumors. Before and after each procedure, cardiac devices were interrogated and reprogrammed by a trained cardiac electrophysiology fellow. Possible pacer malfunctions included abnormalities on electrocardiographic (EKG) monitoring and alterations in device settings. Our institutional review board approved this Health Insurance Portability and Accountability Act-compliant study. Informed consent for participation in this retrospective study was deemed unnecessary by our review board. Results: During 20 of 22 sessions, no abnormalities were identified in continuous, EKG tracings or pacemaker functions. However, in two sessions significant changes, occurred in pacemaker parameters: inhibition of pacing during RF application in one, session and resetting of mode by RF energy in another session. These changes did not, result in hemodynamic instability of either patient. MW ablation was not associated with, any malfunction. In all 22 sessions, pacemakers were undamaged and successfully reset to original parameters. Conclusion: RF or MW ablation of tumors in liver, kidney, bone and lung can be performed safely in patients with permanent intra-cardiac devices, but careful planning between radiology and cardiology is essential to avoid adverse outcomes.

  19. Duodenopleural Fistula Formation After Percutaneous Radiofrequency Ablation for Recurrent Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Fion S. Chan

    2007-10-01

    Full Text Available Radiofrequency ablation (RFA is a treatment option in the management of unresectable or recurrent hepatocellular carcinoma (HCC. It can be performed either through laparotomy or in a minimally invasive manner by percutaneous, laparoscopic or thoracoscopic routes. Percutaneous RFA is associated with reduced surgical trauma and thus can be performed in patients with significant comorbidities. The procedure can be repeated after short intervals for sequential ablation of multiple liver lesions. However, the associated risks should not be underestimated. This is the first report of a rare complication of duodenopleural fistula after percutaneous RFA of a recurrent subcapsular HCC. The risk of bowel perforation during the ablation of subcapsular HCC requires special attention, since only the position of the tip of the electrode, but not the zone of ablation, can be assessed accurately by imaging during the procedure. Our case demonstrated that there was leakage of bowel content from the duodenal injury site into the pleural cavity through the RFA track. Subsequent uncontrolled infection resulted in empyema thoracis and led to the death of the patient.

  20. Transseptal versus transaortic approach for radiofrequency ablation in patients with cardioverter-defibrillator and electrical storm.

    Science.gov (United States)

    Pluta, Slawomir; Lenarczyk, Radoslaw; Pruszkowska-Skrzep, Patrycja; Kowalski, Oskar; Sokal, Adam; Sredniawa, Beata; Mazurek, Michal; Kalarus, Zbigniew

    2010-06-01

    Radiofrequency current ablation (RFCA) of ventricular tachycardia (VT) is usually performed using a retrograde transaortic approach. We compared the mapping accuracy, procedural course, safety, and results of VT ablation using transseptal and transaortic route. Twenty-one consecutive patients with ischemic cardiomyopathy and history of electrical storm underwent RFCA with electro-anatomic mapping system. In six patients, ablation was performed with transseptal approach (transseptal group); in 15, retrograde approach to the left ventricle was used (retrograde group). The endocardial surface of the left ventricle was similarly accessible in both methods. Less detailed maps of interventricular septum were constructed with the use of transseptal approach. The RFCA success rate was similar in the transseptal and retrograde groups (83 vs. 80%, p = NS). The median procedural time was 112 min in transseptal vs. 145 min in the retrograde group; radiation exposure was 200 vs. 67 mGy, respectively (both p ablation in patients with malignant, recurrent ventricular arrhythmias. However, limited access to the septal regions with the use of this method has to be remembered. Transseptal approach may be considered as an alternative to the transaortic route in patients with contraindication to the latter.

  1. Radiofrequency Ablation of Functioning Adrenal Adenomas: Preliminary Clinical and Laboratory Findings.

    Science.gov (United States)

    Szejnfeld, Denis; Nunes, Thiago Franchi; Giordano, Endrigo Emanuel; Freire, Fabio; Ajzen, Sergio Aron; Kater, Claudio Elias; Goldman, Suzan Menasce

    2015-10-01

    To evaluate clinical and laboratory findings in patients undergoing radiofrequency (RF) ablation for functioning adrenal adenomas. Eleven adult patients, nine with Conn syndrome and two with Cushing syndrome, underwent percutaneous computed tomography-guided RF ablation for benign adrenal neoplasms. Systolic, diastolic, and mean blood pressure and the number of classes of antihypertensive drugs used by each patient were analyzed before and 1, 4, and 12 weeks after the procedure. Serum hormone levels were analyzed within 30 days before and 12 weeks after the procedure. Of the nine patients with Conn syndrome, eight showed normal serum aldosterone levels after the procedure and one patient had a nodule located very close to the inferior vena cava, resulting in incomplete ablation. The two patients with Cushing syndrome had normal serum and salivary cortisol levels after the procedure. Mean aldosterone concentration at baseline was 63.3 ng/dL ± 28.0 and decreased to 13.3 ng/dL ± 13.5 at 12 weeks postoperatively (P = .008). Systolic, diastolic, and mean blood pressures decreased significantly in the first week after the procedure (P < .001) and remained stable during further follow-up. In patients with Conn syndrome or Cushing syndrome, percutaneous RF ablation of functioning adrenal adenomas may result in normalization of hormone secretion, improvement in blood pressure, and reduced need for antihypertensive drugs. Copyright © 2015 SIR. Published by Elsevier Inc. All rights reserved.

  2. Analysis of factors affecting local tumor progression of colorectal cancer liver metastasis after radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong Hee; Cho, Yun Ku; Choi, Seung A; Kim, Mi Young; Lee, Ho Suk [Veterans Health Service Medical Center, Seoul (Korea, Republic of)

    2017-03-15

    The purpose of this study was to evaluate the independent predictive factors for local tumor progression (LTP) of colorectal liver metastasis (CRLM) after radiofrequency ablation (RFA). Patients with CRLM were included in the analysis if nodules were up to five in number, each nodule was ≤ 5 cm, and RFA was performed in our center from January 2006 to December 2015. Univariate and multivariate analyses to identify the predictors of LTP were performed by using a Cox proportional hazard model. Overall, 58 tumors from 38 patients were included in this study. LTP occurred in 14 tumors from 9 patients. The overall 1- and 3-year LTP rates were 23.5% and 29.4%, respectively. Multivariate analysis showed that tumor size > 2 cm and insufficient ablative margin were two independently significant adverse prognostic factors for LTP (p = 0.045 and 0.022, respectively). The 3-year LTP rates for 33 and 25 tumors with and without sufficient ablative margin were 4.5% and 61.2%, respectively. The difference was statistically significant (p < 0.001). The difference in the 3-year LTP rates according to the tumor size was not statistically significant (p = 0.791). Insufficient ablative margin seems to be the most potent predictor of LTP after RFA of CRLM.

  3. Local release of dexamethasone from polymer millirods effectively prevents fibrosis after radiofrequency ablation.

    Science.gov (United States)

    Blanco, Elvin; Weinberg, Brent D; Stowe, Nicholas T; Anderson, James M; Gao, Jinming

    2006-01-01

    Recent studies show that after radiofrequency (RF) ablation, fibrosis occurs at the ablation boundary, hindering anticancer drug transport from a locally implanted polymer depot to the ablation margin, where tumors recur. The purpose of this study is to investigate strategies that can effectively deliver dexamethasone (DEX), an anti-inflammatory agent, to prevent fibrosis. Polymer millirods consisting of poly(D,L-lactide-co-glycolide) (PLGA) were loaded with either DEX complexed with hydroxypropyl beta-cyclodextrin (HPbeta-CD), or an NaCl and DEX mixture. In vitro release studies show that DEX complexed with HPbeta-CD released 95% of the drug after 4 days, compared to 14% from millirods containing NaCl and DEX. Rat livers underwent RF ablation and received either DEX-HPbeta-CD-loaded millirods, PLGA millirods with an intraperitoneal (i.p.) DEX injection, or control PLGA millirods alone. After 8 days in vivo, heightened inflammation and the appearance of a well-defined fibrous capsule can be observed in both the control experiments and those receiving a DEX injection (0.29 +/- 0.08 and 0.26 +/- 0.07 mm in thickness, respectively), with minimal inflammation and fibrosis present in livers receiving DEX millirods (0.04 +/- 0.01 mm). Results from this study show that local release of DEX prevents fibrosis more effectively than a systemic i.p. injection. (c) 2005 Wiley Periodicals, Inc

  4. Ultrasonography-guided percutaneous radiofrequency ablation for cervical lymph node metastasis from thyroid carcinoma

    Directory of Open Access Journals (Sweden)

    Liping Wang

    2014-01-01

    Full Text Available Purpose: The aim was to explore the efficacy and safety of ultrasonography-guided percutaneous radiofrequency ablation (RFA for cervical lymph node metastases from thyroid carcinoma. Materials and Methods: Eight patients with previous total thyroidectomy and radioiodine therapy were enrolled in this study. A total of 20 cervical lymph node metastases were confirmed by percutaneous biopsy. Participants underwent ultrasonography-guided RFA treatment for all confirmed metastatic lymph nodes. Contrast-enhanced ultrasound (CEUS and sonoelastography were performed to rapidly evaluate treatment responses before and shortly after RFA. Routine follow-up consisted of conventional US, CEUS, sonoelastography, thyroglobulin level, and necessary fine needle aspiration cytology. Results: All eight patients were successfully treated without obvious complications. Post-RFA CEUS showed that total metastatic lymph nodes were ablated. The sonoelastographic score of ablated area elevated significantly shortly after RFA (P < 0.001. With a mean follow-up of 9.4 ± 5.1 months, there were no evidences of recurrence at ablated sites; however, two new cervical recurrent lymph nodes occurred in one case, which was successfully ablated as well. The mass volume shrinkages of the ablated nodes were observed in all cases. We found that 5 treated lymph nodes disappeared, 4 were reduced more than 80%, 9 were reduced between 50% and 80%, and 2 were reduced less than 50%. At the last follow-up evaluation, the serum thyroglobulin levels had decreased in 6 of 8 patients. Conclusion: Ultrasonography-guided percutaneous RFA for cervical lymph node metastasis of thyroid malignancy is a feasible, effective, and safe therapy. This procedure shows a nonsurgical therapeutic option for metastatic lymph nodes in patients with difficult reoperations or inoperations, it may reduce or delay a large number of highly invasive repeated neck dissections.

  5. CT-guided percutaneous radiofrequency ablation of osteoid osteoma: Our experience in 87 patients

    Directory of Open Access Journals (Sweden)

    Anurag Chahal

    2017-01-01

    Full Text Available Purpose: To evaluate the technical and clinical success of radiofrequency ablation of osteoid osteoma and analyze the factors responsible for clinical success. We also tried to investigate the role of follow-up computed tomography (CT imaging. Materials and Methods: This is a prospective study approved by the institute's ethics committee involving 87 patients with appendicular osteoid osteoma. CT-guided radio frequency ablation was performed using a bipolar ablation system. Patients were followed up over 15.4 (4–24 months for pain, and clinical success/failure was determined using established criteria. Patients with clinical failure were taken for repeat ablation. Follow-up CT was obtained at 6 months and correlated with clinical success. Procedural scans were later reviewed for technical success in a blinded manner and correlated with clinical success along with other imaging and patient characteristics. Results: Mean pre-procedure visual analog scale (VAS score was 7.0 ± 0.8. Primary success rate after single session was 86.2%(75/87 patients, and overall success rate after one/two sessions was 96.6%(84/87. No major complications were noted. Technical success rate was 89.7%(78/87. All 9 patients who had a suboptimal needle positioning had recurrence where as three patients had recurrence despite technical success. None of the imaging characteristics or history of prior intervention was significantly associated with clinical success. Follow-up CT showed advanced bone healing in 48 lesions, and was confined to the treatment success group. Alternately, minimal/absent bone healing was seen in all (12 patients of primary treatment failure and 27 patients with treatment success. Conclusions: CT-guided percutaneous radio frequency ablation is a safe and highly effective treatment for osteoid osteomas even in recurrent and residual cases. Technical success is the most important parameter affecting the outcome. Post radio frequency ablation CT

  6. Percutaneous radiofrequency ablation of hepatocellular carcinoma: analysis of 80 patients treated with two consecutive sessions

    Energy Technology Data Exchange (ETDEWEB)

    Rhim, Hyunchul; Kim, Young-sun; Choi, Dongil; Lim, Hyo K.; Park, KoWoon [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea)

    2008-07-15

    This study investigated the reasons for some patients requiring two consecutive sessions of percutaneous radiofrequency (RF) ablation of hepatocellular carcinoma (HCC). We reviewed our database of 1,179 patients (1,624 treatments) with HCCs treated by percutaneous ultrasound (US)-guided RF ablation over 6 years. We retrospectively evaluated 80 patients who required a second session after the first session. The medical records and follow-up CTs were studied. We assessed the reasons for the second session and the patient outcomes. A second session was required in 80 (4.8%) out of 1,642 treatments of percutaneous RF ablation for HCC. The reason for the second session included technical failure related to the patient or the procedure (n=26), technical failure due to residual (n=40), newly detected (n=11) or missed (n=3) tumors found at the immediate follow-up CT. All patients were retreated with a second RFA session the next day. Seventy-five (93%) of 80 patients achieved complete ablation after the second session. The remaining five patients were treated by TACE (n=1), additional RFA (as second treatment at next admission) (n=3), or were lost to follow-up (n=1). After 1 month follow-up, 72 patients (96%) showed complete ablation after the second session. The interventional oncologist should understand the technical reasons for a patient requiring a second session of RF ablation when providing treatment for HCCs and perform careful pre-procedural planning to minimize the need for multi-session procedures. (orig.)

  7. Combined cementoplasty and radiofrequency ablation in the treatment of painful neoplastic lesions of bone.

    Science.gov (United States)

    Munk, Peter L; Rashid, Faisal; Heran, Manraj K; Papirny, Michael; Liu, David M; Malfair, David; Badii, Maziar; Clarkson, Paul W

    2009-07-01

    To assess the safety and effectiveness of combined radiofrequency (RF) ablation and cementoplasty in the treatment of painful neoplastic lesions of bone. The authors performed a retrospective analysis of 25 combined treatments comprising RF ablation followed by injection of polymethylmethacrylate cement performed in 19 patients during a 22-month period. Patients ranged in age from 42 to 82 years (mean, 58.9 years) and included five women and 14 men. Eleven vertebrae (eight lumbar and three thoracic), nine acetabulae, three sacra, one pubis, and one humerus were treated with a total of 36 RF ablations (in several instances, overlapping ablations were used). The location of the primary neoplasm, lesion size, pain before and after the procedure (as determined with a 10-point visual analog scale [VAS]), number of RF treatments, type of device used for cementoplasty, RF time, cement volume, and extravasation were documented. A total of 25 combined RF ablations and cementoplasties were performed. The technical success rate was 100% (25 of 25 treatments). There were seven minor complications: six limited cement extravasations and a transient thermal nerve injury. The mean RF time was 9.1 minutes (range, 6-12 minutes). The mean cement volume injected was 6.1 mL (range, 0.8-16 mL). The mean preprocedure pain (as measured with a VAS) was 7.9 (range, 7.0-9.0) and the mean posttreatment pain was 4.2 (range, 0-6); the difference was statistically significant (mean score, 4.08; 95% confidence interval: 3.92, 4.87; P < .0001) using a paired t test. Combined RF ablation and cementoplasty appears to be safe and effective in the treatment of painful neoplastic lesions of bone.

  8. Imaging Features of Radiofrequency Ablation with Heat-Deployed Liposomal Doxorubicin in Hepatic Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Cheng William, E-mail: williamhongcheng@gmail.com; Chow, Lucy, E-mail: lucychow282@gmail.com [National Institutes of Health, Center for Interventional Oncology, Clinical Center (United States); Turkbey, Evrim B., E-mail: evrimbengi@yahoo.com [National Institutes of Health, Radiology and Imaging Sciences, Clinical Center (United States); Lencioni, Riccardo, E-mail: riccardo.lencioni@med.unipi.it [Pisa University Hospital, Division of Diagnostic Imaging and Intervention, Department of Hepatology and Liver Transplantation (Italy); Libutti, Steven K., E-mail: slibutti@montefiore.org [Albert Einstein College of Medicine, Montefiore-Einstein Center for Cancer Care, Department of Surgery (United States); Wood, Bradford J., E-mail: bwood@nih.gov [National Institutes of Health, Center for Interventional Oncology, Clinical Center (United States)

    2016-03-15

    IntroductionThe imaging features of unresectable hepatic malignancies in patients who underwent radiofrequency ablation (RFA) in combination with lyso-thermosensitive liposomal doxorubicin (LTLD) were determined.Materials and MethodsA phase I dose escalation study combining RFA with LTLD was performed with peri- and post- procedural CT and MRI. Imaging features were analyzed and measured in terms of ablative zone size and surrounding penumbra size. The dynamic imaging appearance was described qualitatively immediately following the procedure and at 1-month follow-up. The control group receiving liver RFA without LTLD was compared to the study group in terms of imaging features and post-ablative zone size dynamics at follow-up.ResultsPost-treatment scans of hepatic lesions treated with RFA and LTLD have distinctive imaging characteristics when compared to those treated with RFA alone. The addition of LTLD resulted in a regular or smooth enhancing rim on T1W MRI which often correlated with increased attenuation on CT. The LTLD-treated ablation zones were stable or enlarged at follow-up four weeks later in 69 % of study subjects as opposed to conventional RFA where the ablation zone underwent involution compared to imaging acquired immediately after the procedure.ConclusionThe imaging features following RFA with LTLD were different from those after standard RFA and can mimic residual or recurrent tumor. Knowledge of the subtle findings between the two groups can help avoid misinterpretation and proper identification of treatment failure in this setting. Increased size of the LTLD-treated ablation zone after RFA suggests the ongoing drug-induced biological effects.

  9. Temperature-controlled radiofrequency ablation of different tissues using two-compartment models.

    Science.gov (United States)

    Singh, Sundeep; Repaka, Ramjee

    2016-08-30

    This study aims to analyse the efficacy of temperature-controlled radiofrequency ablation (RFA) in different tissues. A three-dimensional, 12 cm cubical model representing the healthy tissue has been studied in which spherical tumour of 2.5 cm has been embedded. Different body sites considered in the study are liver, kidney, lung and breast. The thermo-electric analysis has been performed to estimate the temperature distribution and ablation volume. A programmable temperature-controlled RFA has been employed by incorporating the closed-loop feedback PID controller. The model fidelity and integrity have been evaluated by comparing the numerical results with the experimental in vitro results obtained during RFA of polyacrylamide tissue-mimicking phantom gel. The results revealed that significant variations persist among the input voltage requirements and the temperature distributions within different tissues of interest. The highest ablation volume has been produced in hypovascular lungs whereas least ablation volume has been produced in kidney being a highly perfused tissue. The variation in optimal treatment time for complete necrosis of tumour along with quantification of damage to the surrounding healthy tissue has also been reported. The results show that the surrounding tissue environment significantly affects the ablation volume produced during RFA. The optimal treatment time for complete tumour ablation can play a critical role in minimising the damage to the surrounding healthy tissue and ensuring safe and risk free application of RFA. The obtained results emphasise the need for developing organ-specific clinical protocols and systems during RFA of tumour.

  10. Ultrasound-Guided Genicular Nerve Thermal Radiofrequency Ablation for Chronic Knee Pain

    Directory of Open Access Journals (Sweden)

    Joshua Wong

    2016-01-01

    Full Text Available Osteoarthritis (OA of the knee is one of the most common joint diseases affecting adults in the United States. For elderly patients with multiple medical comorbidities who do not wish to undergo total knee arthroplasty (TKA, lifestyle modification, pharmacologic management, and injections are the mainstay of therapy. Previously, pain management interventions were limited to intra-articular joint injections and viscosupplementation with hyaluronic acid. Fluoroscopic-guided techniques for radiofrequency ablation (RFA of the genicular nerves have been previously described and a recent cadaveric study suggests that ultrasound-guided genicular nerve blocks can be performed accurately. We performed an ultrasound-guided radiofrequency ablation of the genicular nerves in 88-year-old woman who had deferred surgical management given her age. Following successful ultrasound guided diagnostic genicular nerve blocks, she proceeded to RFA using the same ultrasound guided technique. The procedure resulted in significant pain relief and improvement in overall function for greater than 6 months. The use of ultrasound provides a relatively rapid and noninvasive method to directly visualize genicular nerves and surrounding vasculature. Our case suggests that, for genicular nerve blockade and RFA, ultrasound may be a useful alternative to fluoroscopy. Not only did the procedure result in significant pain relief that has persisted for greater than 6 months but also more importantly her function status and quality of life were improved.

  11. Ultrasound-Guided Genicular Nerve Thermal Radiofrequency Ablation for Chronic Knee Pain.

    Science.gov (United States)

    Wong, Joshua; Bremer, Nicholas; Weyker, Paul D; Webb, Christopher A J

    2016-01-01

    Osteoarthritis (OA) of the knee is one of the most common joint diseases affecting adults in the United States. For elderly patients with multiple medical comorbidities who do not wish to undergo total knee arthroplasty (TKA), lifestyle modification, pharmacologic management, and injections are the mainstay of therapy. Previously, pain management interventions were limited to intra-articular joint injections and viscosupplementation with hyaluronic acid. Fluoroscopic-guided techniques for radiofrequency ablation (RFA) of the genicular nerves have been previously described and a recent cadaveric study suggests that ultrasound-guided genicular nerve blocks can be performed accurately. We performed an ultrasound-guided radiofrequency ablation of the genicular nerves in 88-year-old woman who had deferred surgical management given her age. Following successful ultrasound guided diagnostic genicular nerve blocks, she proceeded to RFA using the same ultrasound guided technique. The procedure resulted in significant pain relief and improvement in overall function for greater than 6 months. The use of ultrasound provides a relatively rapid and noninvasive method to directly visualize genicular nerves and surrounding vasculature. Our case suggests that, for genicular nerve blockade and RFA, ultrasound may be a useful alternative to fluoroscopy. Not only did the procedure result in significant pain relief that has persisted for greater than 6 months but also more importantly her function status and quality of life were improved.

  12. Treatment of pathologic spinal fractures with combined radiofrequency ablation and balloon kyphoplasty

    Directory of Open Access Journals (Sweden)

    Tzanakakis George

    2009-11-01

    Full Text Available Abstract Background In oncologic patients with metastatic spinal disease, the ideal treatment should be well tolerated, relieve the pain, and preserve or restore the neurological function. The combination of fluoroscopic guided radiofrequency ablation (RFA and kyphoplasty may fulfill these criteria. Methods We describe three pathological vertebral fractures treated with a combination of fluoroscopic guided RFA and kyphoplasty in one session: a 62-year-old man suffering from a painful L4 pathological fracture due to a plasmocytoma, a 68-year-old man with a T12 pathological fracture from metastatic hepatocellular carcinoma, and a 71-year-old man with a Th12 and L1 pathological fracture from multiple myeloma. Results The choice of patients was carried out according to the classification of Tomita. Visual analog score (VAS and Oswestry disability index (ODI were used for the evaluation of the functional outcomes. The treatment was successful in all patients and no complications were reported. The mean follow-up was 6 months. Marked pain relief and functional restoration was observed. Conclusion In our experience the treatment of pathologic spinal fractures with combined radiofrequency ablation and balloon kyphoplasty is safe and effective for immediate pain relief in painful spinal lesions in neurologically intact patients.

  13. Catheter based radiofrequency ablation of renal nerves for the treatment of resistant hypertension

    Directory of Open Access Journals (Sweden)

    Markus P. Schlaich

    2013-03-01

    Full Text Available Introduction Resistant hypertension is a common and growing clinical problem characterized by the failure to attain target blood pressure levels despite adequate use of at least three antihypertensive agents. Objectives The aim of this article is to emphasize the role of novel approaches to treat resistant hypertension. Materials and methods After an excursus on the physiological role of renal nerves on kidney function, volume homeostasis and blood pressure control, this article describes the radiofrequency ablation technology to obtain kidneys denervation. Results Activation of the sympathetic nervous system plays a prominent role as a major regulator of circulatory and metabolic control. The kidneys have a particularly dense afferent sensory and efferent sympathetic innervation and are thereby strategically positioned to be origin as well as target of sympathetic activation. In this context, recent evidence suggests that a novel catheter-based approach to functionally denervate the human kidneys using radiofrequency ablation technology may provide a safe and effective treatment alternative for resistant hypertension and its adverse consequences. Conclusions Despite the availability of numerous safe and effective pharmacological therapies to treat elevated blood pressure, novel therapeutic approaches are warranted to improve the management and prognosis of patients with refractory hypertension. Several clinical trials are currently conducted and planned to further substantiate the blood pressure lowering efficacy of this novel renal denervation procedure.

  14. Nursing and quality of life in patients with atrial fibrillation before and after radiofrequency ablation.

    Science.gov (United States)

    Pavelková, Zdeňka; Bulava, Alan

    2014-01-01

    The importance of nursing and patient quality of life is a top concern for medical professionals. Therefore, participation by medical professionals in raising awareness and continuously supporting improvements in nursing care is an essential part of improving patient quality of life. Modern medical techniques and procedures are changing rapidly, particularly in the field of cardiology. This has resulted in changing roles and increased responsibility for nurses and confirms the necessity for changing the perception of nurses relative to their role in the medical environment and to patient care. This paper presents the results from the first phase of a research project and focuses on quality of life and problematic areas associated with the needs of patients with atrial fibrillation before and after radiofrequency catheter ablation. Atrial fibrillation is one of the most common supraventricular arrhythmias. Its incidence in the general population has risen significantly over the last twenty years. The objective of this research was to assess those areas, which are considered by patients to be problematic before therapeutic intervention. The research was realized through a quantitative survey using a modified questionnaire. Results showed that AF reduced the quality of life both physically and psychologically (i.e. increased levels of anxiety and depression). Results also showed that radiofrequency catheter ablation was able to alleviate symptoms associated with AF and was also able to increase patient quality of life.

  15. Cardiac ablation procedures

    Science.gov (United States)

    Catheter ablation; Radiofrequency catheter ablation; Cryoablation - cardiac ablation; AV nodal reentrant tachycardia - cardiac ablation; AVNRT - cardiac ablation; Wolff-Parkinson-White Syndrome - cardiac ablation; Atrial fibrillation - cardiac ablation; Atrial flutter - ...

  16. Temperature-controlled radiofrequency ablation of cardiac tissue: an in vitro study of the impact of electrode orientation, electrode tissue contact pressure and external convective cooling

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, A

    1999-01-01

    A variety of basic factors such as electrode tip pressure, flow around the electrode and electrode orientation influence lesion size during radiofrequency ablation, but importantly is dependent on the chosen mode of ablation. However, only little information is available for the frequently used...... temperature-controlled mode. The purpose of the present experimental study was to evaluate the impact during temperature-controlled radiofrequency ablation of three basic factors regarding electrode-tissue contact and convective cooling on lesion size....

  17. Percutaneous Renal Tumor Ablation: Radiation Exposure During Cryoablation and Radiofrequency Ablation

    Energy Technology Data Exchange (ETDEWEB)

    McEachen, James C., E-mail: james.mceachen2@gmail.com [Mayo Clinic, Division of Preventive, Occupational, and Aerospace Medicine (United States); Leng, Shuai; Atwell, Thomas D. [Mayo Clinic, Department of Radiology (United States); Tollefson, Matthew K. [Mayo Clinic, Department of Urology (United States); Friese, Jeremy L. [Mayo Clinic, Department of Radiology (United States); Wang, Zhen; Murad, M. Hassan [Mayo Clinic, Division of Preventive, Occupational, and Aerospace Medicine (United States); Schmit, Grant D. [Mayo Clinic, Department of Radiology (United States)

    2016-02-15

    IntroductionOnce reserved solely for non-surgical cases, percutaneous ablation is becoming an increasingly popular treatment option for a wider array of patients with small renal masses and the radiation risk needs to be better defined as this transition continues.Materials and MethodsRetrospective review of our renal tumor ablation database revealed 425 patients who underwent percutaneous ablation for treatment of 455 renal tumors over a 5-year time period. Imparted radiation dose information was reviewed for each procedure and converted to effective patient dose and skin dose using established techniques. Statistical analysis was performed with each ablative technique.ResultsFor the 331 cryoablation procedures, the mean DLP was 6987 mGycm (SD = 2861) resulting in a mean effective dose of 104.7 mSv (SD = 43.5) and the mean CTDI{sub vol} was 558 mGy (SD = 439) resulting in a mean skin dose of 563.2 mGy (SD = 344.1). For the 124 RFA procedures, the mean DLP was 3485 mGycm (SD = 1630) resulting in a mean effective dose of 50.3 mSv (SD = 24.0) and the mean CTDI{sub vol} was 232 mGy (SD = 149) resulting in a mean skin dose of 233.2 mGy (SD = 117.4). The difference in patient radiation exposure between the two renal ablation techniques was statistically significant (p < 0.001).ConclusionBoth cryoablation and RFA imparted an average skin dose that was well below the 2 Gy deterministic threshold for appreciable sequela. Renal tumor cryoablation resulted in a mean skin and effective radiation dose more than twice that for RFA. The radiation exposure for both renal tumor ablation techniques was at the high end of the medical imaging radiation dose spectrum.

  18. Case Experience of Radiofrequency Ablation for Benign Thyroid Nodules: From an Ex Vivo Animal Study to an Initial Ablation in Taiwan

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    Ming-Tsang Lee

    2016-03-01

    Full Text Available Radiofrequency ablation (RFA is a minimally invasive technique, used with ultrasound or computed tomography guidance, which can produce tissue coagulation necrosis in various kinds of tumors in the human body. In the past 10 years, numerous studies about RFA in benign thyroid nodules have been published. Reviewing these studies, we noticed that the effectiveness of ablation was higher when it was performed with the “moving-shot technique” via an internally cooled electrode. A consensus statement published from the Korean Society of Radiology also suggested the moving-shot technique as a standard ablation procedure for benign thyroid nodule ablation in Korea. In Taiwan, most symptomatic benign nodules are currently treated with surgical removal. RFA for mass lesions is primarily performed for the treatment of metastatic hepatic tumors. In our case, we have attempted to introduce RFA for benign thyroid nodules in Taiwan. Because endocrinologists in Taiwan were not familiar with this technique, we adopted a stepwise approach in learning how to perform RFA. We conducted ex vivo animal ablation exercises to gain experience in setting the radiofrequency generator for the right ablation mode and appropriate power output. The thyroid nodule volume reduction rate after 1 year of follow up was approximately 50% in this case. The most important thing we learned from this trial is that we confirmed the safety of thyroid nodule ablation. To the best of our knowledge, this is the first reported study of RFA of a thyroid nodule in Taiwan.

  19. 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

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    Maryam Moshkani Farahani

    2011-02-01

    Full Text Available 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

  20. Selective Angiography Using the Radiofrequency Catheter: An Alternative Technique for Mapping and Ablation in the Aortic Cusps.

    Science.gov (United States)

    Roca, Ivo; Rivas, Nuria; Francisco, Jaume; Perez, Jordi; Acosta, Gabriel; Oristrell, Gerard; Terricabres, Maria; Garcia-Dorado, David; Moya, Angel

    2017-01-01

    Ablation in aortic cusps could be necessary in up to 15% of the patients, especially in para-Hisian atrial tachycardia and ventricular arrhythmias arising from outflow tracts. Risk of coronary damage has led to recommendation of systematic coronary angiography (CA) during the procedure. Other image tests as intravascular (ICE) or transesophageal echocardiography (TEE) have been proposed. Both methods have limitations: additional vascular access for ICE and need for additional CA in some patients in case of TEE. We describe an alternative method to assess relation of catheter tip and coronary ostia during ablation in aortic cusps without additional vascular accesses by performing selective angiography with the ablation catheter. We prospectively evaluated 12 consecutive patients (69.3 ± 8.5, 6 female) who underwent ablation in right (1), left (5), and noncoronary cusps (6). We performed angiography through the ablation cooled tip radiofrequency catheter at the ablation site. Ablation was effective in 91.6% of the patients (3 patients needed additional ablation out of coronary cusps: pulmonary cusp, right ventricular outflow tract (RVOT), and coronary sinus and 1 patient underwent a second procedure because recurrence). No complications occurred neither during procedure nor follow-up (6.2 ± 3.8 months). No technical problems occurred with the ablation catheter after contrast injection. Selective angiography through a cooled-tip radiofrequency ablation catheter is feasible to assess relation of coronary ostia and ablation site when ablation in aortic cusps. It allows continuous real-time assessment of this relation, avoids the need for additional vascular accesses and no complications occurred in our series. © 2016 Wiley Periodicals, Inc.

  1. [Percutaneous radiofrequency ablation therapy with left single lung ventilation for liver carcinoma in the hepatic dome].

    Science.gov (United States)

    Sun, Wen-bing; Wang, Zhen-yuan; Zhang, Yan-feng; Ding, Xue-mei; Wang, Bao-qiang

    2007-09-01

    To evaluate the advantages of percutaneous radiofrequency ablation (PRFA) therapy with contralateral single lung ventilation (SLV) for liver carcinoma in the hepatic dome (LCHD). The clinical data of 10 patients (the SLV group) with LCHD consecutively treated from January to December 2006 were retrospectively analyzed. And another 10 cases (the control group) with LCHD treated from January 2004 to December 2005 were selected with a strict inclusion criterion for compared test according to rules of same diagnosis, similar tumor bulk and site, same sex, similar age and liver function. The patients' ages and tumor diameters of the 2 groups were compared with t-test and the rates of complications and incomplete tumor ablation were compared with chi2-test. There was no statistical difference in ages and tumor diameters between the 2 groups (P > 0.05). The average number of radiofrequency ablation needle punctures in the SLV group was significantly less than the control group (3.4 +/- 0.4 vs. 6.1 +/- 0.8, P pleural effusion (n = 1). There was no mortality in the 2 groups. Though the rate of incomplete tumor necrosis in the SLV group was not statistically lower than that in the control group (10% vs. 40%), the occurrence rate of the undesirable event (complication and incomplete tumor necrosis) of the SLV group was significantly lower than that of the control group (10% vs. 60%, P < 0.05). The durations and costs of operating procedure were not significantly different between the 2 groups. Left SLV makes PRFA for LCHD more efficient, effective and safe.

  2. CT-guided radiofrequency ablation in osteoid osteoma: Result from a tertiary cancer centre in India

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    Suyash S Kulkarni

    2017-01-01

    Full Text Available Aims: The aim of this study is to evaluate the clinical efficacy of computed tomography (CT-guided radiofrequency (RF ablation as a minimally invasive therapy for osteoid osteoma. Materials and Methods: This is a retrospective analysis of prospectively maintained data of 43 symptomatic osteoid osteoma patients who were treated by radiofrequency ablation (RFA. Forty out of 43 patients were naive cases and underwent primary treatment for osteoid osteoma with RFA, whereas 3 patients included in the study underwent RFA for local recurrence after having undergone surgical treatment. Diagnosis was based on clinical and characteristic imaging findings, and biopsy was done for cases with atypical presentation. Pre and post procedure Visual Analog Score (VAS was documented in all cases. Monopolar RFA system was used in all patients, and the electrode was placed within the lesion nidus under CT guidance coaxially through 11G introducer needle. Ablation was performed at 90° C for 5 min. Results: Technical success rate of intranidal placement of electrode was 100%. The primary clinical success in our study was 97.7% (42 of 43, and the secondary clinical success was 100%.Pre and postprocedure VAS score in our study group was 7.8 and 0.4, respectively. Mean follow-up period in our study was 48 months (Range: 4–129 months.One patient had recurrence of pain 4 years after treatment and was treated successfully by a second session. Minor complications were seen in 3 patients with two cases of RF pad burns and one case of skin burn at the treatment site, and these were managed conservatively. No patients developed temporary/permanent neurological deficits, and no procedure-related mortality was seen in our study. Conclusion: CT-guided percutaneous RFA is a simple, safe, minimally invasive, and highly effective treatment option for osteoid osteoma with good long-term pain control and potentially low disease recurrence.

  3. In vivo experimental study on the effects of fluid in increasing the efficiency of radiofrequency ablation.

    Science.gov (United States)

    Sun, Yi-Xin; Cheng, Wen; Han, Xue; Liu, Zhao; Wang, Qiu-Cheng; Shao, Hua

    2014-01-01

    Radiofrequency ablation (RFA) is the most widely used and studied method internationally for the local treatment of liver tumors. However, the extension of coagulation necrosis in one RFA procedure is limited and incomplete coverage of the damaged area can lead to a high local recurrence rate. In this study, we compared the effects of different solutions in enhancing hepatic radiofrequency by establishing a rabbit VX2 liver cancer model. We also determined the optimal solution to maximise effects on the extent of RFA-induced coagulation necrosis. Thirty VX2 tumor rabbits were randomly assigned to five groups: group A, RFA alone; group B, RFA with anhydrous ethanol injection; group C, RFA with 5% hypertonic saline injection; group D, RFA with lidocaine injection; and group E, RFA with a mixed solution. Routine ultrasound examinations and contrast-enhanced ultrasound (CEUS) of the ablation areas were performed after RFA. Then, we measured the major axis and transverse diameter and compared the areas of coagulation necrosis induced by RFA. The mean ablation area range increased in groups B, C and especially E, and the scopes were greater compared with group A. Preoperative application of anhydrous ethanol, hypertonic saline, lidocaine and the mixed solution (groups B, C, D and E, respectively) resulted in larger coagulation necrosis areas than in group A (p<0.05). Among the groups, the coagulation necrosis areas in group E was largest, and the difference was statistically significant compared with other groups (p<0.05). Pathological findings were consistent with imaging results. A mixture of dehydrated alcohol, hypertonic saline and lidocaine injected with RFA increases the extent of coagulation necrosis in the liver with a single application, and the mixed solution is more effective than any other injection alone.

  4. Safety of the open-irrigated ablation catheter for radiofrequency ablation: safety analysis from six clinical studies.

    Science.gov (United States)

    Waldo, Albert L; Wilber, David J; Marchlinski, Francis E; Stevenson, William G; Aker, Brenda; Boo, Lee Ming; Jackman, Warren M

    2012-09-01

    The open-irrigated catheter is used most frequently for atrial and ventricular radiofrequency ablation (RFA), and is often considered as the standard by which new ablation systems are compared. But few data have been published concerning its safety. This report provides a comprehensive safety analysis of the use of an open-irrigated catheter for RFA of atrial flutter, ventricular tachycardia, and atrial fibrillation in 1,275 patients in six rigorously monitored, prospective, multicenter studies. This analysis is of data from six studies conducted as part of both Food and Drug Administration-mandated investigational device exemption studies and postapproval studies. The six studies span a period of more than 10 years. All serious RFA complications and vascular access complications that occurred within seven days postprocedure were included. The number of patients who experienced any acute serious RFA complication in these studies combined was 4.9% (63/1,275). The two earliest studies were conducted when the open-irrigated catheter was first introduced, and accounted for 55.6% of the complications. In the first atrial flutter ablation study, RFA complications decreased by 60% (15.4%-6.2%) after a proctoring program was initiated during the study. For all studies, vascular access complications ranged between from 0.5%-4.7%, and no stroke or transient ischemic attack was reported within 7 days postprocedure. No significant pulmonary vein stenosis was reported from the atrial fibrillation studies. A proctoring program, careful fluid management, and absence of char and coagulum contributed to the safe use of the open-irrigated RFA catheter. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

  5. Transarterial Chemoembolization Combined with Either Radiofrequency or Microwave Ablation in Management of Hepatocellular Carcinoma

    Science.gov (United States)

    Abdelaziz, Ashraf Omar; Abdelmaksoud, Ahmed Hosni; Nabeel, Mohamed Mahmoud; Shousha, Hend Ibrahim; Cordie, Ahmed Abdelmonem; Mahmoud, Sherif Hamdy; Medhat, Eman; Omran, Dalia; Elbaz, Tamer Mahmoud

    2017-01-01

    Introduction: Local ablative therapy and trans arterial chemoembolization (TACE) are applied to ablate non resectable hepatocellular carcinoma (HCC). Combination of both techniques has proven to be more effective. We aimed to study combined ablation techniques and assess survival benefit comparing TACE with radiofrequency (RFA) versus TACE with microwave (MWA) techniques. Methods: We retrospectively studied 22 patients who were ablated using TACE-RFA and 45 with TACE-MWA. All were classified as Child A-B and lesions did not exceed 5 cm in diameter. TACE was followed within two weeks by either RFA or MWA. We recorded total and partial ablation rates and complication rates. Survival analysis was then performed. Results: TACE-MWA showed a higher tendency to provide complete response rates than TACE-RFA (P 0.06). This was particularly evident with lesions sized 3-5 cm (P 0.01). Rates of complications showed no significant difference between the groups. Overall median survival was 27 months. The overall actuarial probability of survival was 80.1% at 1 year, 55% at 2 years, and 36.3% at 3 years. The recurrence free survival at 1 year, 2years and 3 years for the TACE-RFA group was 70%, 42% and 14% respectively and for TACE-MWA group 81.2%, 65.1% and 65.1% without any significant difference (P 0.1). In relation to the size of focal lesions, no statistically significant difference in the survival rates was detected between the groups. Conclusion: TACE-MWA led to better response rates than TACE-RFA with tumors 3-5 cm, with no difference in survival rates. Creative Commons Attribution License

  6. Temperature-Controlled Radiofrequency Ablation for Pulmonary Vein Isolation in Patients With Atrial Fibrillation.

    Science.gov (United States)

    Iwasawa, Jin; Koruth, Jacob S; Petru, Jan; Dujka, Libor; Kralovec, Stepan; Mzourkova, Katerina; Dukkipati, Srinivas R; Neuzil, Petr; Reddy, Vivek Y

    2017-08-01

    Saline irrigation improved the safety of radiofrequency (RF) ablation, but the thermal feedback for energy titration is absent. To allow temperature-controlled irrigated ablation, a novel irrigated RF catheter was designed with a diamond-embedded tip (for rapid cooling) and 6 surface thermocouples to reflect tissue temperature. High-resolution electrograms (EGMs) from the split-tip electrode allowed rapid lesion assessment. The authors evaluated the preclinical and clinical performance of this catheter for pulmonary vein (PV) isolation. Using the DiamondTemp (DT) catheter, pigs (n = 6) underwent discrete atrial ablation in a temperature control mode (60°C/50 W) until there was ∼80% EGM amplitude reduction. In a single-center clinical feasibility study, 35 patients underwent PV isolation with the DT catheter (study group); patients were planned for PV remapping after 3 months, regardless of symptomatology. A control group included 35 patients who underwent PV isolation with a standard force-sensing catheter. Porcine lesion histology revealed transmurality in 51 of 55 lesions (92.7%). In patients, all PVs were successfully isolated; no char or thrombus formation was observed. Compared with the control group, the study cohort had shorter mean RF application duration (26.3 ± 5.2 min vs. 89.2 ± 27.2 min; p PV reconduction (0 of 35 vs. 5 of 35; p = 0.024). At 3 months, 23 patients underwent remapping: 39 of 46 PV pairs (84.8%) remained durably isolated in 17 of these patients (73.9%). This first-in-human series demonstrated that temperature-controlled irrigated ablation produced rapid, efficient, and durable PV isolation. (ACT DiamondTemp Temperature-Controlled and Contact Sensing RF Ablation Clinical Trial for Atrial Fibrillation [TRAC-AF]; NCT02821351). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  7. CT-guided radiofrequency ablation of osteoid osteoma: long-term results

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    Cioni, Roberto; Armillotta, Nicola; Bargellini, Irene; Zampa, Virna; Cappelli, Carla; Vagli, Paola; Bartolozzi, Carlo [Department of Oncology, Transplants and Advanced Technologies in Medicine, Division of Diagnostic and Interventional Radiology, University of Pisa, Via Roma 67, 56126, Pisa (Italy); Boni, Giuseppe [Division of Nuclear Medicine, University of Pisa, Via Roma 67, 56126, Pisa (Italy); Marchetti, Stefano; Consoli, Vincenzo [Department of Orthopedics, University of Pisa, Via Roma 67, 56126, Pisa (Italy)

    2004-07-01

    The aim of the study was to assess the safety and efficacy of CT-guided percutaneous radiofrequency (RF) ablation of osteoid osteoma (OO). From 1997 to 2001, RF ablation was performed on 38 patients with OO, diagnosed clinically and by radiography, scintigraphy, contrast-enhanced MRI, and CT. Treatment was performed via percutaneous (n=29) or surgical (n=9) access, under CT guidance in all cases, with an 18-gauge straight electrode. Patients were discharged within 24 h and followed up clinically (at 1 week and every 6-12 months) and with MRI (at 6 months) and scintigraphy (after 1 year). The technical success rate was 100%. Complications occurred in two patients, consisting in local skin burns. The follow-up range was 12-66 months (mean {+-} SD, 35.5{+-}7.5 months). Prompt pain relief and return to normal activities were observed in 30 of 38 patients. Persistent pain occurred in eight patients; two patients refused further RF ablation and were treated surgically; RF ablation was repeated in six cases achieving successful results in five. One patient reported residual pain and is being evaluated for surgical excision. Primary and secondary clinical success rates were 78.9 (30/38 patients) and 97% (35/36 patients), respectively. CT-guided RF ablation of OO is safe and effective. Persistent lesions can be effectively re-treated. Several imaging modalities are needed for the diagnosis of OO and for the follow-up after treatment, particularly in patients with persistent symptoms. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Panagiotis Paliogiannis

    2014-01-01

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

  9. CD95 is a key mediator of invasion and accelerated outgrowth of mouse colorectal liver metastases following radiofrequency ablation

    NARCIS (Netherlands)

    Nijkamp, Maarten W.; Hoogwater, Frederik J. H.; Steller, Ernst J. A.; Westendorp, B. Florien; van der Meulen, Taco A.; Leenders, Martijn W. H.; Borel Rinkes, Inne H. M.; Kranenburg, Onno

    2010-01-01

    Recently, we have shown that micro-metastases, in the hypoxic transition zone surrounding lesions generated by radiofrequency ablation (RFA), display strongly accelerated outgrowth. CD95 is best known for its ability to induce apoptosis but can also promote tumorigenesis in apoptosis-resistant tumor

  10. Endoscopic radiofrequency ablation for early esophageal squamous cell neoplasia: report of safety and effectiveness from a large prospective trial

    NARCIS (Netherlands)

    He, Shun; Bergman, Jacques; Zhang, Yueming; Weusten, Bas; Xue, Liyan; Qin, Xiumin; Dou, Lizhou; Liu, Yong; Fleischer, David; Lu, Ning; Dawsey, Sanford M.; Wang, Gui-Qi

    2015-01-01

    Endoscopic radiofrequency ablation (RFA) is an established therapy for Barrett's esophagus. Preliminary reports, limited by low patient numbers, also suggest a possible role for RFA in early esophageal squamous cell neoplasia (ESCN). The aim of this study was to evaluate the safety and effectiveness

  11. Radiofrequency ablation for the endoscopic eradication of esophageal squamous high grade intraepithelial neoplasia and mucosal squamous cell carcinoma

    NARCIS (Netherlands)

    van Vilsteren, F. G.; Alvarez Herrero, L.; Pouw, R. E.; ten Kate, F. J.; Visser, M.; Seldenrijk, C. A.; van Berge Henegouwen, M. I.; Weusten, B. L.; Bergman, J. J.

    2011-01-01

    Background and study aims: Radiofrequency ablation (RFA) with or without prior endoscopic resection safely and effectively removes early neoplasia in Barrett's esophagus. We speculated that this approach might also be suited for early squamous neoplasia of the esophagus. The aim of the study was to

  12. The Mid-Term Results of Patients who Underwent Radiofrequency Atrial Fibrillation Ablation Together with Mitral Valve Surgery

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    Abdurrahim Çolak

    Full Text Available Abstract Objetive: Saline-irrigated radiofrequency ablation, which has been widely used for surgical treatment of atrial fibrillation in recent years, is 80-90% successful in achieving sinus rhythm. In our study, our surgical experience and mid-term results in patients who underwent mitral valve surgery and left atrial radiofrequency ablation were analyzed. Methods: Forty patients (15 males, 25 females; mean age 52.05±9.9 years; range 32-74 underwent surgery for atrial fibrillation associated with mitral valvular disease. All patients manifested atrial fibrillation, which started at least six months before the surgical intervention. The majority of patients (36 patients, 90% were in NYHA class III; 34 (85% patients had rheumatic heart disease. In addition to mitral valve surgery and radiofrequency ablation, coronary artery bypass, DeVega tricuspid annuloplasty, left ventricular aneurysm repair, and left atrial thrombus excision were performed. Following discharge from the hospital, patients' follow-up was performed as outpatient clinic examinations and the average follow-up period of patients was 18±3 months. Results: While the incidence of sinus rhythm was 85.3% on the first postoperative day, it was 80% during discharge and 71% in the 1st year follow-up examination. Conclusion: Radiofrequency ablation is an effective method when it is performed by appropriate surgical technique. Its rate for returning to sinus rhythm is as high as the rate of conventional surgical procedure.

  13. Real-time in vivo assessment of radiofrequency ablation of human colorectal liver metastases using diffuse reflectance spectroscopy

    NARCIS (Netherlands)

    Tanis, E.; Spliethoff, Jarich; Evers, Daniel; Evers, D.J.; Langhout, G.C.; Snaebjornsson, P.; Prevoo, W.; Hendriks, B.H.; Ruers, Theo J.M.

    2016-01-01

    Background The success of radiofrequency (RF) ablation is limited by the inability to assess thermal tissue damage achieved during or immediately after the procedure. The goal of this proof-of-principle study was to investigate whether diffuse reflectance (DR) spectroscopy during and after RF

  14. Safety of pulmonary vein isolation and left atrial complex fractionated atrial electrograms ablation for atrial fibrillation with phased radiofrequency energy and multi-electrode catheters

    NARCIS (Netherlands)

    Mulder, A.A.W.; Balt, J.C.; Wijffels, M.C.; Wever, E.F.; Boersma, L.V.

    2012-01-01

    AIMS: Recently, a multi-electrode catheter system using phased radiofrequency (RF) energy was developed specifically for atrial fibrillation (AF) ablation: the pulmonary vein ablation catheter (PVAC), the multi-array septal catheter (MASC), and the multi-array ablation catheter (MAAC). Initial

  15. Hydrochloric acid-enhanced radiofrequency ablation for treating a large hepatocellular carcinoma with spontaneous rapture: a case report.

    Science.gov (United States)

    Huang, Jin-Hua; Morelli, John N; Ai, Fei; Zou, Ru-Hai; Gu, Yang-Kui; Gao, Fei; Zhang, Tian-Qi; Yao, Wang; Jiang, Xiong-Ying; Zhang, Yan-Yang

    2017-01-07

    A ruptured hepatocellular carcinoma (HCC) is often fatal. In addition to surgery and transarterial embolization, radiofrequency ablation (RFA) might be another option for treating a ruptured HCC. Unfortunately, conventional RFA has a limited ablation zone; as such, it is rarely used to treat ruptured tumors. This case was a 60-year-old man who had a large, ruptured HCC in which hydrochloric acid (HCl)-enhanced RFA successfully controlled the bleeding and made the tumor completely necrotic. Considering the effectiveness of HCl-enhanced RFA in achieving hemostasis and tumor ablation, it might be a new option for treating large, ruptured HCCs.

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

    Science.gov (United States)

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

    2004-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Dos Santos, Icaro; Da Rocha, Adson Ferreira; Menezes, Leonardo Rax [Department of Electrical Engineering, University of Brasilia, Brasilia, DF 70910-900 (Brazil); Haemmerich, Dieter; Schutt, David [Division of Pediatric Cardiology, Medical University of South Carolina, 165 Ashley Ave., Charleston, SC 29425 (United States)], E-mail: icaro@ieee.org

    2009-02-07

    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 cm{sup 3}, 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.

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

    Directory of Open Access Journals (Sweden)

    Tomoko Saito

    2015-05-01

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

  19. Radiofrequency Ablation of Renal Tumors: Four-Year Follow-Up Results in 47 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soo Dong; Yoon, Seong Guk; Sung, Gyung Tak [Dong-A University College of Medicine, Busan (Korea, Republic of)

    2012-09-15

    To retrospectively evaluate the intermediate results of radiofrequency ablation (RFA) of small renal masses (SRMs). Percutaneous or laparoscopic RFA was performed on 48 renal tumors in 47 patients. The follow-up studies included a physical examination, chest radiography, creatinine level, and contrast-enhanced CT or MRI. To confirm the pathologic criteria of complete ablation, 35 patients underwent a follow-up biopsy. Recurrence was defined as contrast enhancement on imaging studies after 3 months, lesion growth at subsequent imaging, or viable cancer cells on follow-up biopsy. Technical success was achieved in 43 (89.6%) of 48 renal tumors. The mean tumor size was 2.3 cm and the mean follow-up period was 49.6 months. Repeated RFA was necessary in 5 tumors due to incomplete ablation. The overall complication rate was 35.8%, of which 96.2% were mild complications. Serum creatinine levels at 12 months after RFA did not differ from those before RFA (1.28 vs. 1.36 mg/dL). Four patients were found to have recurrence at various follow-up intervals, and distant metastasis was not found in any cases. RFA appears to be a useful treatment for selected patients with SRMs. Our 4-year follow-up results disclose an excellent therapeutic outcome with RFA, while achieving effective local tumor control.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Gustavo Glotz de, E-mail: gglima.pesquisa@gmail.com; Gomes, Daniel Garcia; Gensas, Caroline Saltz; Simão, Mariana Fernandez; Rios, Matheus N.; Pires, Leonardo Martins; Kruse, Marcelo Lapa; Leiria, Tiago Luiz Luz [Instituto de Cardiologia, Fundação Universitária de Cardiologia, Porto Alegre, RS (Brazil)

    2013-11-15

    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. To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation. 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. 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. 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.

  1. Percutaneous radiofrequency ablation of osteoid osteomas. Technique and results; Perkutane Radiofrequenzablation von Osteoidosteomen. Technik und Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Bruners, P.; Penzkofer, T. [Lehrstuhl fuer Angewandte Medizintechnik, Helmholtz Inst. fuer Biomedizinische Technik, RWTH Aachen (Germany); Guenther, R. W.; Mahnken, A. [Klinik fuer Radiologische Diagnostik, Universitaetsklinikum RWTH Aachen (Germany)

    2009-08-15

    Purpose: Osteoid osteoma is a benign primary bone tumor that typically occurs in children and young adults. Besides local pain, which is often worse at night, prompt relief due to medication with acetylsalicylic acid (ASS) is characteristic for this bone lesion. Because long-term medication with ASS does not represent an alternative treatment strategy due to its potentially severe side effects, different minimally invasive image-guided techniques for the therapy of osteoid osteoma have been developed. In this context radiofrequency (RF) ablation in particular has become part of the clinical routine. The technique and results of image-guided RF ablation are compared to alternative treatment strategies. Materials and Methods: Using this technique, an often needle-shaped RF applicator is percutaneously placed into the tumor under image guidance. Then a high-frequency alternating current is applied by the tip of the applicator which leads to ionic motion within the tissue resulting in local heat development and thus in thermal destruction of the surrounding tissue including the tumor. Results: The published primary and secondary success rates of this technique are 87 and 83%, respectively. Surgical resection and open curettage show comparable success rates but are associated with higher complication rates. In addition image-guided RF ablation of osteoid osteomas is associated with low costs. (orig.)

  2. Efficacy and safety of radiofrequency ablation combined with transcatheter arterial chemoembolization for hepatocellular carcinomas compared with radiofrequency ablation alone: A time to event meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin; Hu, Yanan; Ren, Mudan; Lu, Xin Lan; Lu, Gui Fang; He, Shui Xiang [Dept. of Gastroenterology, First Affiliated Hospital of Xi' an Jiaotong University, Xi' an (China)

    2016-02-15

    To compare the efficacy and safety of combined radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) with RFA alone for hepatocellular carcinomas (HCC). Randomized controlled trial (RCT) studies that compared the clinical or oncologic outcomes of combination therapy of TACE and RFA versus RFA for the treatment of HCC were identified through literature searches of electronic databases (Pubmed, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure, and Google Scholar). Hazard ratios (HRs) or odds ratios (ORs) with their corresponding 95% confidence interval (CI) were combined as the effective value to assess the summary effects. The strength of evidence was rated by the Grading of Recommendations Assessment, Development, and Evaluation system. Six RCTs with 534 patients were eligible for inclusion in this meta-analysis. The meta-analysis showed that the combination of TACE and RFA is associated with a significantly longer overall survival (HR = 0.62, 95% CI: 0.49-0.78, p < 0.001) and recurrence-free survival (HR = 0.55, 95% CI: 0.40-0.76, p < 0.001) in contrast with RFA monotherapy. The seemingly higher incidence of major complications in the combination group compared with RFA group did not reach statistical significance (OR = 1.17, 95% CI: 0.39-3.55, p = 0.78). In patients with HCC, the combination of TACE and RFA is associated with significantly higher overall survival and recurrence-free survival, as compared with RFA monotherapy, without significant difference in major complications.

  3. Ultrasound-guided radiofrequency thermal ablation of normal kidney in a rabbit model: correlation with CT and histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Won; Lee, Jeong Min; Kin, Chong Soo; Lee, Sang Hun [College of Medicine, Chonbuk National Univ., Chonju (Korea, Republic of)

    2002-01-01

    To assess the feasibility and safety of using a cooled-tip electrode to perform percutaneous radiofrequency ablation of kidney tissue in rabbits, and to evaluate the ability of CT to reveal the appearance and extent of tissue necrosis during follow-up after ablation. Using ultrasound guidance, a 17-G cooled-tip electrode was inserted into the right lower portion of the kidney in 26 New Zealand White rabbits. Radiofrequency was applied for 2 mins, and biphasic helical CT scanning was used to assess tissue destruction and the presence or absence of complications immediately after the procedure and at 24 hrs, 2 and 3 days, and 1,2,3,4,5,6 and 7 weeks. The study had three phases: acute (immediately killed : N=10); subacute (killed at 24 hrs (n=3), 2 days (n=3), 3 days (n=1) : N=7); chronic (killed at 1 week (n=4), 2 weeks (n=2), 4 weeks (n=1), 7 weeks (n=1): N=8). After the animals were killed, their kidneys were histopathologically examined and the radiologic and pathologic findings of lesion size and configuration were correlated. In each instance, ultrasound-guided radiofrequency ablations of the lower pole of the kidney were technically successful. Contrast-enhanced biphasic helical CT revealed regions of hypoattenuation devoid of parenchymal enhancement, and these correlated closely with true pathologic lesion size (r=0.884; p>0.05). In subacute and chronic models, CT scanning revealed gradual spontaneous resorption of the ablated lesion and the presence of perilesional calcification. Histopathologically, in the acute phase the ablated lesion showed coagulative necrosis and infiltration of inflammatory cells, and in the chronic phase there was clear cut necrosis of glomeruli, tubules and renal interstitium, with diminishing inflammatory response and peripheral fibrotic tissue formation. Ultrasound-guided renal radiofrequency ablation is technically feasible and safe. In addition, the avascular lesion measured at contrast-enhanced helical CT closely correlated with

  4. Histopathology of breast cancer after magnetic resonance-guided high-intensity focused ultrasound and radiofrequency ablation.

    Science.gov (United States)

    Knuttel, Floortje M; Waaijer, Laurien; Merckel, Laura G; van den Bosch, Maurice A A J; Witkamp, Arjen J; Deckers, Roel; van Diest, Paul J

    2016-08-01

    Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation and radiofrequency ablation (RFA) are being researched as possible substitutes for surgery in breast cancer patients. The histopathological appearance of ablated tissue has not been studied in great detail. This study aimed to compare histopathological features of breast cancer after MR-HIFU ablation and RFA. MR-HIFU ablation and RFA were performed in- and ex-vivo. Tumours in six mastectomy specimens were partially ablated with RFA or MR-HIFU. In-vivo MR-HIFU ablation was performed 3-6 days before excision; RFA was performed in the operation room. Tissue was fixed in formalin and processed to haematoxylin and eosin (H&E) and cytokeratin-8 (CK-8)-stained slides. Morphology and cell viability were assessed. Ex-vivo ablation resulted in clear morphological changes after RFA versus subtle differences after MR-HIFU. CK-8 staining was decreased or absent. H&E tended to underestimate the size of thermal damage. In-vivo MR-HIFU resulted in necrotic-like changes. Surprisingly, some ablated lesions were CK-8-positive. Histopathology after in-vivo RFA resembled ex-vivo RFA, with hyper-eosinophilic stroma and elongated nuclei. Lesion borders were sharp after MR-HIFU and indistinct after RFA. Histopathological differences between MR-HIFU-ablated tissue and RF-ablated tissue were demonstrated. CK-8 was more reliable for cell viability assessment than H&E when used directly after ablation, while H&E was more reliable in ablated tissue left in situ for a few days. Our results contribute to improved understanding of histopathological features in breast cancer lesions treated with minimally invasive ablative techniques. © 2016 John Wiley & Sons Ltd.

  5. Impact of cavotricuspid isthmus morphology in CRYO versus radiofrequency ablation of typical atrial flutter.

    Science.gov (United States)

    Saygi, Serkan; Bastani, Hamid; Drca, Nikola; Insulander, Per; Wredlert, Christer; Schwieler, Jonas; Jensen-Urstad, Mats

    2017-04-01

    Cryoablation (CRYO) is an alternative to radiofrequency (RF) for catheter ablation of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL). We aimed to study whether different CTI morphologies had different impacts on procedural success for CRYO and RF. This study randomized 153 patients with CTI-dependent AFL (median age 65 years; range 34-82) to RF or CRYO (78 CRYO; 75 RF). Biplane angiography (RAO 30° and LAO 60°) was done before the ablation procedure and isthmuses were classified as straight (n = 81), concave (n = 43) or pouch-like (n = 29). RF was performed with a 3.5-mm open-irrigated tip catheter and CRYO was performed with a 9 F, 8-mm tip catheter. The ablation endpoint was bidirectional block of CTI. Acute procedural success was achieved in 70/75 patients in the RF group and in 72/78 patients in the CRYO group. With regard to CRYO or RF, acute procedural success rates were similar between the three isthmus types: straight: CRYO (92%) and RF (96%); concave: CRYO (92%) and RF (94%); and pouch-like: CRYO (94%) and RF (85%). There were no significant differences regarding success rate between the different morphologies in the CRYO or the RF group. The CTI was longer in patients with acute failure compared to the patients with acute success (38 ± 7 mm versus 33 ± 6 mm, p = 0.045). The CTI morphology did not influence the acute success rate for either the CRYO or the RF ablation of CTI-dependent AFL. A longer CTI was associated with a lower success rate regardless of energy source.

  6. Treatment of metastatic spinal lesions with a navigational bipolar radiofrequency ablation device: a multicenter retrospective study.

    Science.gov (United States)

    Anchala, Praveen R; Irving, Winston D; Hillen, Travis J; Friedman, Michael V; Georgy, Bassem A; Coldwell, Douglass M; Tran, Nam D; Vrionis, Frank D; Brook, Allan; Jennings, Jack W

    2014-01-01

    Spinal metastatic lesions are a common occurrence among oncology patients and contribute to significant morbidity. Treatment options have been limited in their effectiveness and scope to this point. This study aims to report the safety and efficacy of radiofrequency ablation (RFA) of malignant spinal lesions using a novel RFA bipolar tumor ablation system which includes a navigational electrode containing 2 active thermocouples. IRB approved multicenter retrospective review of patients receiving RFA as a treatment of metastatic osseous lesions between March 2012 and March 2013. This study consists of patients from 5 large academic centers. One hundred twenty-eight metastatic lesions were identified in 92 patients who underwent a total of 96 procedures. Cement augmentation was performed when the vertebral body was at risk or had a pathological fracture. Visual analogue scale (VAS) scores were obtained preoperatively as well as postoperatively at the one week, one month, and 6 month time points. Interval change in the patients' pain medications was recorded. Postoperative imaging was used to assess tumor burden at the treated level when available. RFA was technically successful in all of the lesions without complication or thermal injury. Our study demonstrated significant (P postoperatively. In our largest center, 54% of our patients experienced a decrease and 30% had no change in their pain medications postoperatively. Sixty-two percent of the spinal lesions in this largest institution were located in the posterior vertebral body. Post-ablation imaging confirmed size of ablation zones consistent with that measured by the thermocouples. The main limitations of this study are the heterogeneous patient population, data set, and potential confounding variable of concurrent cement augmentation. The STAR System is an RFA device that was safely and effectively used in the treatment of spine metastatic osseous lesions. This new device allows RFA treatment of previously

  7. Robot-assisted radiofrequency ablation of primary and secondary liver tumours: early experience

    Energy Technology Data Exchange (ETDEWEB)

    Abdullah, Basri Johan Jeet [University of Malaya, Department of Biomedical Imaging, Faculty of Medicine, Kuala Lumpur (Malaysia); Yeong, Chai Hong [University of Malaya, University of Malaya Research Imaging Centre, Faculty of Medicine, Kuala Lumpur (Malaysia); Goh, Khean Lee [University of Malaya, Department of Internal Medicine, Faculty of Medicine, Kuala Lumpur (Malaysia); Yoong, Boon Koon [University of Malaya, Department of Surgery, Faculty of Medicine, Kuala Lumpur (Malaysia); Ho, Gwo Fuang [University of Malaya, Department of Oncology, Faculty of Medicine, Kuala Lumpur (Malaysia); Yim, Carolyn Chue Wai [University of Malaya, Department of Anesthesia, Faculty of Medicine, Kuala Lumpur (Malaysia); Kulkarni, Anjali [Perfint Healthcare Corporation, Florence, OR (United States)

    2014-01-15

    Computed tomography (CT)-compatible robots, both commercial and research-based, have been developed with the intention of increasing the accuracy of needle placement and potentially improving the outcomes of therapies in addition to reducing clinical staff and patient exposure to radiation during CT fluoroscopy. In the case of highly inaccessible lesions that require multiple plane angulations, robotically assisted needles may improve biopsy access and targeted drug delivery therapy by avoidance of the straight line path of normal linear needles. We report our preliminary experience of performing radiofrequency ablation of the liver using a robotic-assisted CT guidance system on 11 patients (17 lesions). Robotic-assisted planning and needle placement appears to have high accuracy, is technically easier than the non-robotic-assisted procedure, and involves a significantly lower radiation dose to both patient and support staff. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Shungo Yukumi

    2015-01-01

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

  9. Current status of transcatheter arterial chemoembolization combined with radiofrequency ablation in treatment of primary liver cancer

    Directory of Open Access Journals (Sweden)

    LYU Tianshi

    2016-01-01

    Full Text Available In recent years, more and more therapeutic methods have been applied for the treatment of primary liver cancer; however, since most lesions develop from progressive liver disease or liver cirrhosis, primary liver cancer is still a refractory malignant tumor. Although surgical resection and liver transplantation are radical therapeutic methods, they are not applicable to most patients due to complex issues related to transplantation and insidious onset of such disease. With the improvement in equipment and technology, the interventional therapies for primary liver cancer have been taken more seriously, especially transcatheter arterial chemoembolization and percutaneous radiofrequency ablation. This article investigates the effect and feasibility of the combination of these two therapies for primary liver cancer and introduces the research advances in interventional therapy for primary liver cancer.

  10. Which patients will benefit from percutaneous radiofrequency ablation of colorectal liver metastases? Critically appraised topic.

    LENUS (Irish Health Repository)

    McGrane, Siobhan

    2012-02-03

    In clinical radiology, there are numerous examples of new techniques that were initially enthusiastically promoted and then subsequently abandoned when early promise was not realized in routine patient care. Appropriateness of new or established interventional radiology techniques to specific clinical conditions must be determined from clinical experience, from communication with experts in the field and\\/or careful review of available medical literature, and on an individual patient basis by means of review of clinical notes and diagnostic imaging studies. For patients with liver neoplasms, regional techniques such as radiofrequency ablation (RFA) have been developed and are now the subject of ongoing research. This article describes the utilization of Evidence-Based Practice (EBP) techniques as a means of deciding the appropriateness of percutaneous RFA in treating colorectal liver metastases (CLM).

  11. ANALYSIS OF FACTORS AFFECTING OUTCOME OF ULTRASOUND-GUIDED RADIOFREQUENCY HEAT ABLATION FOR TREATMENT OF PRIMARY HYPERPARATHYROIDISM IN DOGS.

    Science.gov (United States)

    Bucy, Daniel; Pollard, Rachel; Nelson, Richard

    2017-01-01

    Radiofrequency (RF) parathyroid ablation is a noninvasive treatment for hyperparathyroidism in dogs. There are no published data assessing factors associated with RF parathyroid ablation success or failure in order to guide patient selection and improve outcome. The purpose of this retrospective analytical study was to determine whether imaging findings, biochemical data, or concurrent diseases were associated with RF heat ablation treatment failure. For inclusion in the study, dogs must have had a clinical diagnosis of primary hyperparathyroidism, undergone cervical ultrasound and RF ablation of abnormal parathyroid tissue, and must have had at least 3 months of follow-up information available following the date of ultrasound-guided parathyroid ablation. Dogs were grouped based on those with recurrent or persistent hypercalcemia and those without recurrent or persistent hypercalcemia following therapy. Parathyroid nodule size, thyroid lobe size, nodule location, and presence of concurrent disease were recorded. Recurrence of hypercalcemia occurred in 9/32 dogs that had ablation of abnormal parathyroid tissue (28%) and one patient had persistent hypercalcemia (3%) following parathyroid ablation. Nodule width (P = 0.036), height (P = 0.028), and largest cross-sectional area (P = 0.023) were larger in dogs that had recurrent or persistent hypercalcemia following ablation. Hypothyroidism was more common in dogs with recurrent disease (P = 0.044). Radiofrequency ablation was successful in 22/32 (69%) dogs. Larger parathyroid nodule size and/or concurrent hypothyroidism were associated with treatment failure in dogs that underwent ultrasound-guided RF parathyroid nodule ablation. © 2016 American College of Veterinary Radiology.

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

    Science.gov (United States)

    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. Copyright © 2015 Elsevier Ltd. All

  13. Radiofrequency ablation to treat loco-regional recurrence of well-differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Jung, So Lyung; Kim, Bum Soo; Ahn, Kook Jin [Dept. of Radiology, eoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); and others

    2014-12-15

    To evaluate the efficacy of radiofrequency ablation (RFA) in the treatment of loco-regional, recurrent, and well-differentiated thyroid carcinoma. 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. 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 mm{sup 3} to 6.2 +/- 27.9 mm{sup 3}, 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%). Radiofrequency ablation can be effective in treating loco-regional, recurrent, and well-differentiated thyroid carcinoma in patients at high surgical risk.

  14. Hysterosalpingography After Radiofrequency Endometrial Ablation and Hysteroscopic Sterilization as a Concomitant Procedure.

    Science.gov (United States)

    Hopkins, Matthew R; Laughlin-Tommaso, Shannon K; Wall, Darci J; Breitkopf, Daniel M; Creedon, Douglas J; El-Nashar, Sherif A; Famuyide, Abimbola O

    2015-09-01

    To evaluate the accuracy of hysterosalpingography (HSG) in patients who underwent concomitant radiofrequency endometrial ablation and hysteroscopic sterilization. This historical cohort study was conducted at a midwestern academic medical center. A total of 186 women (94 with combined procedure and 92 with sterilization alone) were identified as having undergone intervention between January 1, 2003, and June 30, 2011. Two reviewers blinded to the surgical procedure interpreted the standard clinically indicated HSGs in each group. The primary outcome assessed was the inability to rely on the microinserts for contraception based on HSG interpretation using manufacturers' guidelines (unsatisfactory HSG). Position of the devices and occlusion of tubes were assessed on all 3-month and, when available, all 6-month repeat HSGs. At the 3-month HSG, 5 of 76 (6.6%, 95% confidence interval [CI] 2.2-14.7%) in the sterilization-only group had unsatisfactory HSG compared with 13 of 71 (18.3%, 95% CI 10.1-29.3%) in the combined group (P=.03). After accounting for the seven patients who underwent repeat HSG at 6 months, 3 of 76 (3.95%, 95% CI 0.8-11.1%) in the sterilization-only group had unsatisfactory HSG compared with 13 of 71 (18.31%, 95% CI 10.1-29.3%) in the combined group (P=.005). After completing all clinically indicated HSGs, patients who undergo concomitant radiofrequency endometrial ablation and hysteroscopic sterilization have an approximate fivefold increase (odds ratio 5.45, 95% CI 1.48-20.0) in the rate of unsatisfactory HSG for purposes of documenting tubal occlusion. II.

  15. Safety and feasibility of endoscopic biliary radiofrequency ablation treatment of extrahepatic cholangiocarcinoma.

    Science.gov (United States)

    Laquière, A; Boustière, C; Leblanc, S; Penaranda, G; Désilets, E; Prat, F

    2016-03-01

    Biliary bipolar radiofrequency ablation (RFA) is a new treatment for extrahepatic cholangiocarcinoma (CCA) currently under evaluation. The purpose of this study was to evaluate the safety, particularly biliary fistula occurrence, and the feasibility of biliary RFA in a homogeneous group of patients treated using the same RFA protocol. Twelve patients with inoperable or unresectable CCA were included in a bicentric case series study. After removal of biliary plastic stents, a radiofrequency treatment with a new bipolar probe (Habib™ EndoHBP) was applied. The energy was delivered by a RFA generator (VIO 200 D), supplying electrical energy at 350 kHz and 10 W for 90 s. At the end of the procedure, one or more biliary stents were left in place. Adverse events were assessed per-procedure and during follow-up visits. CCA was confirmed in all patients by histology (66%), locoregional evolution or metastatic evolution. The types of CCA were Bismuth I stage (N = 4), Bismuth II stage (N = 3), Bismuth III stage (N = 2) and Bismuth IV stage (N = 3). No serious adverse events occurred within 30 days following endoscopic treatment: One patient had a sepsis due to bacterial translocation on day 1 and another had an acute cholangitis on day 12 due to early stent migration. No immediate or delayed biliary fistula was reported. The ergonomics of the probe made treatment easy in 100 % of cases. Mean survival was 12.3 months. Endoscopic radiofrequency treatment of inoperable CCA appears without major risks and is feasible. No major adverse events or biliary fistula were identified.

  16. Endovascular radiofrequency ablation. Effect on the vein diameter using the ClosureFast(®) catheter.

    Science.gov (United States)

    Bauzá Moreno, Hernán; Dotta, Mariana; Katsini, Roxana; Marquez Fosser, Carolina; Rochet, Sofía; Pared, Carlos; Martinez, Hugo

    2016-01-01

    Endovascular radiofrequency with first generation catheters was not successful due to its technical difficulty and restrictions in veins with diameters larger than 12mm. However, using the new catheter there is not enough scientific evidence to affirm that the diameter represents a technical limitation. The aim of this study was to evaluate and compare pre and post-operative venous trunks diameter, aiming at the reduction of size after 6 months with last generation catheters. Retrospective observational and descriptive study on a cohort of patients with insufficiency of the great saphenous vein, small saphenous vein and anterior accessory vein operated on with last generation radiofrequency catheters. The diameters were evaluated in the pre and post-operative period with ultrasound. Between 2007 and 2014 a total of 365 ablations were performed in veins with an average diameter of 9±3.1mm showing a reduction of it after 6 months with a mean value of 5.2±0.8mm (P<.0001). Total occlusion was also observed in 100% of cases and complications such as deep vein thrombosis in 0.5% and heat-induced thrombosis in 1.1%. A significant reduction in venous diameter after endovascular treatment with the new ClosureFast(®) catheters was checked, even in veins with diameters greater than 12mm. Copyright © 2016 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. A comparison of microwave ablation and bipolar radiofrequency ablation both with an internally cooled probe: Results in ex vivo and in vivo porcine livers

    Energy Technology Data Exchange (ETDEWEB)

    Yu Jie, E-mail: bqyjbb@sina.com.cn [Department of Interventional Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Liang Ping, E-mail: liangping301@hotmail.com [Department of Interventional Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Yu Xiaoling, E-mail: dyuxl301@yahoo.com.cn [Department of Interventional Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Liu Fangyi, E-mail: fangyi0317@163.com [Department of Interventional Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Chen Lei, E-mail: Chenlei301@hotmail.com [Department of Otolaryngology, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Wang Yang, E-mail: wangyang301@hotmail.com [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China)

    2011-07-15

    Purpose: The purpose of this study was to compare the effectiveness of microwave (MW) ablation and radiofrequency (RF) ablation using a single internally cooled probe in a hepatic porcine model. Materials and methods: In the ex vivo experiment, MW ablations (n = 40) were performed with a 2450 MHz and 915 MHz needle antenna, respectively at 60 W, 70 W power settings. Bipolar RF ablations (n = 20) were performed with a 3-cm (T30) and 4-cm (T40) active tip needle electrodes, respectively at a rated power 30 W and 40 W according to automatically systematic power setting. In the in vivo experiment, the 2450 MHz and 915 MHz MW ablation both at 60 W and T30 bipolar RF ablation at 30 W were performed (n = 30). All of the application time were 10 min. Long-axis diameter (Dl), short-axis diameter (Ds), ratio of Ds/Dl, the temperature data 5 mm from the needle and the time of temperature 5 mm from the needle rising to 54 deg. C were measured. Results: Both in ex vivo and in vivo models, Ds and Dl of 915 MHz MW ablations were significantly larger than all the RF ablations (P < 0.05); the Ds for all the 2450 MHz MW ablations were significantly larger than that of T30 RF ablations (P < 0.05). 2450 MHz MW and T30 RF ablation tended to produce more elliptical-shaped ablation zone. Tissue temperatures 5 mm from the needle were considerably higher with MW ablation, meanwhile MW ablation achieved significantly faster rate of temperature rising to 54 deg. C than RF ablation. For in vivo study after 10 min of ablation, the Ds and Dl of 2450 MHz MW, 915 MHz MW and Bipolar RF were 2.35 {+-} 0.75, 2.95 {+-} 0.32, 1.61 {+-} 0.33 and 3.86 {+-} 0.81, 5.79 {+-} 1.03, 3.21 {+-} 0.51, respectively. Highest tissue temperatures 5 mm from the needle were 80.07 {+-} 12.82 deg. C, 89.07 {+-} 3.52 deg. C and 65.56 {+-} 15.31 deg. C and the time of temperature rising to 54 deg. C were respectively 37.50 {+-} 7.62 s, 24.50 {+-} 4.09 s and 57.29 {+-} 23.24 s for three applicators. Conclusion: MW

  18. Ultrasonography-guided percutaneous radiofrequency ablation of hepatocellular carcinomas: A feasibility scoring system for planning sonography

    Energy Technology Data Exchange (ETDEWEB)

    Rhim, Hyunchul, E-mail: rhimhc@skku.ed [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Choi, Dongil; Kim, Young-sun; Lim, Hyo K. [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Choe, Bong-Keun [Department of Preventive Medicine, Kyung Hee University School of Medicine, Seoul (Korea, Republic of)

    2010-08-15

    Purpose: This study was designed to evaluate whether a feasibility scoring system for planning sonography is a reliable predictor of a safe and complete ablation in ultrasonography (US)-guided percutaneous radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs). Materials and methods: We retrospectively evaluated the therapeutic outcomes of 108 consecutive patients (M:F, 78:30; mean age, 57.4 years) with a single nodular HCC (mean diameter, 2.0 cm) treated by percutaneous RFA. All patients were assessed for the feasibility of performing an RFA at planning sonography prior to the ablation. The feasibility scoring system consisted of five categories: the safe electrode path (P); the vital organs adjacent to the RFA zone (O); tumor size (S); tumor conspicuity (C); and the heat-sink effect (H). Each category was divided into a four-point scale [1-4]. If a score of 4 in any category was determined, the patient was not considered to be a suitable candidate for percutaneous RFA. We assessed if the score of each category, safety score (P + O), and curability score (S + C + H) correlated with a safe and complete ablation using the chi-squared test and likelihood ratio test for trend. Results: The technical success rate was 100% (108/108) based on CT images obtained immediately after ablation. There was no 30-day mortality after RFA. There were major complications (one case of severe vasovagal reflex, one case of hemoperitoneum and one case of a pseudoaneurysm) in three (2.7%) patients, and minor complications (one case of a biloma, one case of subsegmental infarction and one case of abscess) in three (2.7%) patients. Post-ablation syndrome as a side effect was noted in 38 (35.1%) of 108 patients. The primary technique effectiveness rate at 1 month was 95.1% (105/108). Local tumor progression was noted in eight (7.6%) of 105 patients during the follow-up period (range, 3.0-11.5 months; median, 5.8 months; mean, 5.7 months). There was no significant single category

  19. Radiofrequency Atrial Fibrillation Ablation Technique in Patients with Mitral Valve Surgery and Left Atrial Reduction Procedures

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    Pouya Nezafati1

    2015-10-01

    Full Text Available Background: About half of all patients who undergo mitral valve surgery suffer from atrial fibrillation (AF. Cox described the surgical cut-and-sew Maze procedure, which is an effective surgical method but has some complications. This study was designed to evaluate the efficacy of a substitution method of radiofrequency ablation (RFA for patients undergoing mitral valve surgery with AF.Methods: We evaluated 50 patients, comprising 40 men and 10 women at a mean age of 61.8 ± 7.5 years, who underwent mitral valve surgery with RFA between March 2010 and August 2013. All the patients had permanent AF with an enlarged left atrium (LA. The first indication for surgery was underlying organic lesions. Mitral valve replacement or repair was performed in the patients as a single procedure or in combination with aortic valve replacement or coronary artery bypass grafting. Radiofrequency energy was used to create continuous endocardial lesions mimicking most incisions and sutures. We evaluated the pre- and postoperative LA size, duration of aortic cross-clamping, cardiopulmonary bypass time, intensive care unit stay, and total hospital stay.Results: The mean preoperative and postoperative LA sizes were 7.5 ± 1.4 cm and 4.3 ± 0.7 cm (p value = 0.0001, respectively. The mean cardiopulmonary bypass time and the aortic cross-clamping time were 134.3 ± 33.7 minand 109.0 ± 28.4 min, respectively. The average stay at the intensive care unit was 2.1 ± 1.2 days, and the total hospital stay was 8.3 ± 2.4 days. Rebleeding was the only complication, found in one patient. There was no early or late mortality. Eighty-two percent of the patients were discharged in normal sinus rhythm. Five other patients had normal sinus rhythm at 6months' follow-up, and the remaining 4 patients did not have a normal sinus rhythm after 6 months.Conclusion: Radiofrequency ablation, combined with LA reduction, is an effective option for the treatment of permanent AF concomitant with

  20. Efficacy evaluation of laparoscopy assisted ultrasound guided radiofrequency ablation in the treatment of hepatocellular carcinoma beneath the diaphragm

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    Song WANG

    2017-06-01

    Full Text Available Objective To explore the feasibility, safety and efficacy of laparoscopy assisted ultrasound guided radiofrequency ablation (RFA in the treatment of hepatocellular carcinoma (HCC beneath the diaphragm. Methods Twenty- three consecutive patients with solitary HCC beneath the diaphragm were treated by laparoscopy assisted ultrasound guided RFA in the Chinese PLA General Hospital from January 2013 to March 2016. We observed the perioperative complications and followed- up long-term effect. Results All the 23 patients successfully underwent laparoscopy assisted ultrasound guided radiofrequency ablation. No serious complications such as massive hemorrhage, biliary fistula and severe pleural effusion, hemopneumothorax occurred in the patients during perioperative period. CT examination 2-3 days after the operation revealed that the tumor was completely covered by the ablation area. Besides, the survival condition was satisfactory during follow-up period of 9-38 months. Conclusion Laparoscopy-assisted ultrasound-guided radiofrequency ablation is effective and safe for HCC beneath the diaphragm. DOI: 10.11855/j.issn.0577-7402.2017.05.16

  1. Early Stage Hepatocellular Carcinomas Not Feasible for Ultrasound-Guided Radiofrequency Ablation: Comparison of Transarterial Chemoembolization Alone and Combined Therapy with Transarterial Chemoembolization and Radiofrequency Ablation

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, Dongho; Cho, Sung Ki, E-mail: chosk@skku.edu; Shin, Sung Wook; Park, Kwang Bo; Park, Hong Suk; Choo, Sung Wook; Do, Young Soo; Choo, In-wook; Lee, Min Woo; Rhim, Hyunchul; Lim, Hyo Keun [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center (Korea, Republic of)

    2016-03-15

    PurposeTo report the results of combined therapy with transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) for early stage hepatocellular carcinoma (HCC) considered infeasible for ultrasound (US)-guided RFA in comparison with those of TACE monotherapy.MethodsFrom January 2007 through December 2010, 91 patients with early or very early stage HCC infeasible for US-guided RFA received either TACE alone (TACE group; n = 54) or TACE immediately followed by RFA (TACE–RFA group; n = 37) as a first-line treatment. 1-month tumor response, time to progression (TTP), and overall survival (OS) rates were calculated. Univariate and multivariate analyses were performed to identify prognostic factors.ResultsTACE–RFA group showed a better 1-month tumor response than TACE group (P < .001). The mean TTP was 29.7 ± 3.4 months (95 % confidence intervals [CIs] 23.0–36.5) in TACE group and 34.9 ± 2.8 months (95 % CIs 29.4–40.4) in TACE–RFA group. TACE–RFA group had a significantly longer TTP (P = .014). Cumulative 1-, 2-, and 3-year OS rates in the TACE and TACE–RFA groups were 91, 79, and 71 % and 100, 97, and 93 %, respectively (P = .008). Initial treatment of TACE was found to be the only significant risk factor for tumor progression and OS in multivariate analysis.ConclusionTACE–RFA combination therapy appears superior to TACE monotherapy in terms of 1-month tumor response, TTP, and OS when performed for early stage HCC infeasible for US-guided RFA.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  4. Adrenal radiofrequency ablation in swine: change in blood pressure and histopathologic analysis.

    Science.gov (United States)

    Yamakado, Koichiro; Takaki, Haruyuki; Uchida, Katsunori; Nakatsuka, Atsuhiro; Shiraishi, Taizo; Takeda, Kan

    2011-08-01

    To evaluate changes in blood pressure during adrenal radiofrequency ablation (RFA) and analyze histopathologic outcomes in swine adrenal glands. Animal Care Committee approval was obtained for this study. After laparotomy, a single adrenal gland was ablated from each of six animals (six RF sessions total). An internally cooled-tip RF electrode was placed along the long axis of the adrenal gland, and RF energy was applied for 10 min in each adrenal gland. Blood pressure and heart rate were monitored, and serum epinephrine, norepinephrine, and cortisol levels were measured before, during, and after RFA. Histological study was performed using hematoxylin-eosin staining. RFA was completed according to a planned protocol in all adrenal glands. Blood pressure increased to >200 mm Hg after an increase in heart rate during all six RF sessions. Mean serum epinephrine and norepinephrine levels increased significantly during RFA. However, mean cortisol levels showed no significant increase during or after RFA. Histological studies showed adrenal cell necrosis throughout the adrenal glands in all but one pig, with the mean necrosis rate being 99.1 ± 2.3% (range 94.3-100%). Adrenal RFA causes extensive adrenal cell damage and causes catecholamine-induced hypertension.

  5. 27.12 MHz Radiofrequency Ablation for Benign Cutaneous Lesions

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    Dong Hyun Kim

    2016-01-01

    Full Text Available 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.

  6. Potential of Radiofrequency Ablation in Combination with Immunotherapy in the Treatment of Hepatocellular Carcinoma

    Science.gov (United States)

    Li, Guangfu; Staveley-O’Carroll, Kevin F; Kimchi, Eric T

    2016-01-01

    Radiofrequency ablation (RFA) is an important treatment option for patients with early hepatocellular carcinoma (HCC). RFA offers a reliable, reproducible modality to effectively treat hepatic lesions with minimal collateral damage to the surrounding hepatic parenchyma. In addition to traditional open operative techniques, RFA can be performed percutaneously or laparoscopically to minimize the physiologic insult to the patient. Due to the concomitant hepatic damage and dysfunction that often is present in patients with HCC these factors make RFA a frequently utilized therapeutic option. However, RFA is most efficacious in treating smaller tumors (≤ 2 cm), particularly when an ablation margin of ≥ 4–5 mm can be obtained. RFA has diminishing utility in larger tumors, resulting in reduced three and five year overall survival rates when compared to surgical resection. Multimodal approaches to include RFA with other standard and investigational approaches have become a subject of recent interest. RFA capably produces cellular destruction causing liberation of a substantial amount of antigens, many of which are tumor-specific providing a favorable environment for immune recognition. We propose that utilizing an immunotherapeutic approach in conjunction with RFA is the next logical step in the treatment of HCC. In this review, we summarize how RFA modulates antitumor immunity and works in concert with immunotherapy in the treatment of HCC. The information provided is expected to help the future design of novel RFA-integrated immunotherapies which are able to generate durable and powerful antitumor immune response to achieve optimal tumor control. PMID:28042519

  7. Treatment of atrial fibrillation with radiofrequency ablation and simultaneous multipolar mapping of the pulmonary veins.

    Science.gov (United States)

    Rocha Neto, A C; Farias, R L; de Paola, A A

    2001-11-01

    To demonstrate the feasibility and safety of simultaneous catheterization and mapping of the 4 pulmonary veins for ablation of atrial fibrillation. Ten patients, 8 with paroxysmal atrial fibrillation and 2 with persistent atrial fibrillation, refractory to at least 2 antiarrhythmic drugs and without structural cardiopathy, were consecutively studied. Through the transseptal insertion of 2 long sheaths, 4 pulmonary veins were simultaneously catheterized with octapolar microcatheters. After identification of arrhythmogenic foci radiofrequency was applied under angiographic or ultrasonographic control. During 17 procedures, 40 pulmonary veins were mapped, 16 of which had local ectopic activity, related or not with the triggering of atrial fibrillation paroxysms. At the end of each procedure, suppression of arrhythmias was obtained in 8 patients, and elimination of pulmonary vein potentials was accomplished in 4. During the clinical follow-up of 9.6+/-3 months, 7 patients remained in sinus rhythm, 5 of whom were using antiarrhythmic drugs that had previously been ineffective. None of the patients had pulmonary hypertension or evidence of stenosis in the pulmonary veins. Selective and simultaneous catheterization of the 4 pulmonary veins with microcatheters for simultaneous recording of their electrical activity is a feasible and safe procedure that may help ablation of atrial fibrillation.

  8. Drug-refractory ventricular tachycardias after myocarditis: endocardial and epicardial radiofrequency catheter ablation.

    Science.gov (United States)

    Dello Russo, Antonio; Casella, Michela; Pieroni, Maurizio; Pelargonio, Gemma; Bartoletti, Stefano; Santangeli, Pasquale; Zucchetti, Martina; Innocenti, Ester; Di Biase, Luigi; Carbucicchio, Corrado; Bellocci, Fulvio; Fiorentini, Cesare; Natale, Andrea; Tondo, Claudio

    2012-06-01

    Ventricular tachycardia (VT) is a significant therapeutic challenge in patients with myocarditis. This study aimed to assess the efficacy and safety of radiofrequency catheter ablation (RFCA) of VT in patients with myocarditis. We enrolled 20 patients (15 men; age, 42 [28-52] years) with a history of biopsy-proven viral myocarditis and drug-refractory VT; 5 patients presented with electrical storm. The median left ventricular ejection fraction was 55% (45-60%). All patients underwent endocardial RFCA with an irrigated catheter, using contact electroanatomic mapping. Recurrence of sustained VT after endocardial RFCA was treated with additional epicardial RFCA. Endocardial RFCA was acutely successful in 14 patients (70%) while in the remaining 6 (30%) clinical VT was successfully ablated by epicardial RFCA. In 1 patient, hemodynamic instability required an intra-aortic balloon pump to complete RFCA. No major complication occurred during or after RFCA. Over a median follow-up time of 28 (11-48) months, 18 patients (90%) remained free of sustained VT; 2 patients (10%, both with baseline left ventricular ejection fraction≤35%) died of acute heart failure unrelated to ventricular arrhythmias. In patients with myocarditis, RFCA of drug-refractory VT is feasible, safe, and effective. Epicardial RFCA should be considered as an important therapeutic option to increase success rate.

  9. Treatment of atrial fibrillation with radiofrequency ablation and simultaneous multipolar mapping of the pulmonary veins

    Directory of Open Access Journals (Sweden)

    Rocha Neto Almino C.

    2001-01-01

    Full Text Available OBJECTIVE: To demonstrate the feasibility and safety of simultaneous catheterization and mapping of the 4 pulmonary veins for ablation of atrial fibrillation. METHODS: Ten patients, 8 with paroxysmal atrial fibrillation and 2 with persistent atrial fibrillation, refractory to at least 2 antiarrhythmic drugs and without structural cardiopathy, were consecutively studied. Through the transseptal insertion of 2 long sheaths, 4 pulmonary veins were simultaneously catheterized with octapolar microcatheters. After identification of arrhythmogenic foci radiofrequency was applied under angiographic or ultrasonographic control. RESULTS: During 17 procedures, 40 pulmonary veins were mapped, 16 of which had local ectopic activity, related or not with the triggering of atrial fibrillation paroxysms. At the end of each procedure, suppression of arrhythmias was obtained in 8 patients, and elimination of pulmonary vein potentials was accomplished in 4. During the clinical follow-up of 9.6±3 months, 7 patients remained in sinus rhythm, 5 of whom were using antiarrhythmic drugs that had previously been ineffective. None of the patients had pulmonary hypertension or evidence of stenosis in the pulmonary veins. CONCLUSION: Selective and simultaneous catheterization of the 4 pulmonary veins with microcatheters for simultaneous recording of their electrical activity is a feasible and safe procedure that may help ablation of atrial fibrillation.

  10. Transient proarrhythmic state following atrioventricular junction radiofrequency ablation: pathophysiologic mechanisms and recommendations for management.

    Science.gov (United States)

    Nowinski, Karolina; Gadler, Fredrik; Jensen-Urstad, Mats; Bergfeldt, Lennart

    2002-11-01

    The induction of complete heart block by radiofrequency ablation of the atrioventricular junction combined with pacemaker implantation has become an established therapy for rate control in patients with atrial fibrillation who are unresponsive to drugs. Reports of ventricular arrhythmias and sudden death after ablation have, however, raised concerns about safety. Ventricular arrhythmias are usually polymorphic and related to a phase of electrical instability due to an initial prolongation and then slow adaptation of repolarization caused by the change in heart rate and activation sequence. Structural heart disease, and other factors that predispose for the acquired long QT syndrome, seem to add to the risk. Ventricular activation and repolarization stabilize during the first week after the procedure. Routine pacing at 80 beats per minute during this phase is recommended, as well as in hospital monitoring for at least 48 hours. Patients with high-risk features for arrhythmias, such as congestive heart failure or impaired left ventricular function, may require pacing at higher rates. Adjustment of the pacing rate-although rarely below 70 beats per minute-is usually undertaken after a week in most patients, preferably after an electrocardiographic evaluation for repolarization abnormalities at the lower rate.

  11. Radiofrequency versus ethanol ablation for treating predominantly cystic thyroid nodules:A randomized clinical trial

    Energy Technology Data Exchange (ETDEWEB)

    Beak, Jung Hwan; Ha, Eun Ju; Choi, Young Jun; Shong, Young Kee [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Sung, Jin Yong [Dept. of Radiology, Thyroid Center, Daerim St. Mary' s Hospital, Seoul (Korea, Republic of); Kim, Jae Kyun [Dept. of Radiology, Chung Ang University College of Medicine, Seoul (Korea, Republic of)

    2015-12-15

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

  12. Radiofrequency ablation in the treatment of osteoid osteoma: results and complications

    Energy Technology Data Exchange (ETDEWEB)

    Earhart, Jeffrey [Case Western Reserve University, Department of Orthopaedic Surgery, MetroHealth Medical Center, Cleveland, OH (United States); Wellman, David [Hospital for Special Surgery, Department of Orthopaedic Surgery, New York, NY (United States); Donaldson, James [Feinberg School of Medicine at Northwestern University, Department of Medical Imaging, Ann and Robert H. Lurie Children' s Hospital of Chicago, Chicago, IL (United States); Chesterton, Julie [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); King, Erik [Northwestern University Feinberg School of Medicine, Department of Orthopaedic Surgery, Ann and Robert H. Lurie Children' s Hospital of Chicago, Chicago, IL (United States); Janicki, Joseph A. [Northwestern University Feinberg School of Medicine, Department of Orthopaedic Surgery, Children' s Hospital of Chicago, Chicago, IL (United States); Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Orthopaedic Surgery, Chicago, IL (United States)

    2013-07-15

    Percutaneous radiofrequency ablation (RFA) for treatment of osteoid osteoma is effective and avoids the potential complications of open surgical resection. This study evaluates the efficacy of RFA at a single tertiary-care pediatric hospital and highlights an important complication. The medical records of 21 cases of RFA in 21 children between 2004 and 2010 were reviewed retrospectively for demographic data, lesion site, access point and technique for ablation, clinical outcome and complications. Clinical follow-up was available for 17/21 children (81%) at an average of 17.0 months (range 0.5-86.1 months). No persistence or recurrence of pre-procedural pain was noted. Two children (9.5%) had a complication, including a burn to the local skin and muscle requiring local wound care, and a late subtrochanteric femur fracture treated successfully with open reduction internal fixation. RFA is a safe and effective alternative to surgical resection of the osteoid osteoma nidus. When accessing the proximal femur, the risk of late post-procedural fracture must be considered and discussed with the family. An understanding of biomechanical principles in the proximal femur might provide an effective strategy for limiting this risk. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Shivank Bhatia

    2016-01-01

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

  14. Radiofrequency ablation - is a technique finished?; Radiofrequenzablation - ist eine Technik am Ende

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    Wiggermann, P.; Jung, E.M.; Stroszczynski, C. [Klinikum der Universitaet Regensburg (Germany). Institut fuer Roentgendiagnostik

    2012-01-15

    According to current scientific investigations radiofrequency ablation (RFA) as a local ablative tumor therapy for unresectable liver malignancies is currently accepted as the best therapeutic choice. The results of randomized trials justify RFA for small hepatocellular carcinomas (HCC) and RFA is considered to be a viable alternative to resection for inoperable patients with limited hepatic metastatic disease, especially from colorectal cancer (CRC LM). However, surgical resection still remains the gold standard for resectable CRC LM. The intraprocedural image guidance modality of choice is computed tomography (CT) alongside CT fluoroscopy. Contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) are used for preprocedural lesion detection and differentiation as well as for follow-up and can be used to perform RFA procedures as well. This article highlights new developments in RFA. (orig.) [German] Aktuellen wissenschaftlichen Untersuchungen entsprechend stellt die Radiofrequenzablation (RFA) das derzeit kurativste Verfahren zur Behandlung maligner Leberlaesionen dar, wenn eine chirurgische Resektion bzw. Transplantation nicht moeglich ist. Voraussetzung fuer eine erfolgreiche Radiofrequenzablation sind maximal 6 Tumorlaesionen bis zu einer Groesse von maximal 3 cm. Die haeufigsten Indikationen zur RFA-Behandlung sind das hepatozellulaere Karzinom bzw. Lebermetastasen des kolorektalen Karzinoms. Bildgebendes Verfahren der Wahl ist eine kontrastmittelverstaerkte dynamische Spiral-CT, zur Interventionsdurchfuehrung eine CT-Fluoroskopie; alternativ zu letzterer kann eine Ultraschalluntersuchung eingesetzt werden. Die kontrastmittelverstaerkte MRT dient vorwiegend der Tumordetektion und Charakterisierung sowie der postinterventionellen Kontrolle, selten zur Durchfuehrung der RFA. Die aktuelle Arbeit stellt die neuesten Entwicklungen bzgl. der RFA dar. (orig.)

  15. Complications following radiofrequency ablation of the porcine liver through portal vein penetration: radiological findings

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    Kim, Seung Hoon; Lim, Hyo K.; Choi, Dong Gil [Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Jeon, Yong Hwan [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of); Park, Kil Sun [Chungbuk National University College of Medicine, Cheongju (Korea, Republic of)

    2007-07-15

    To evaluate complications after radiofrequency ablation (RFA) of the porcine liver through portal vein penetration. Twelve pigs were divided into two groups. In group I (n = 11) animals, the portal veins were directly penetrated with an electrode, and in the group II (n = 16) animals, the portal veins were located within the expected ablation area. For the group I pigs, RFA were performed for seven minutes after complete portal vein passing of the exposed tip. Gray-scale and Doppler ultrasonography, and CT were performed before and after RFA on the procedure day, and on day two. If any complications were found, the same studies were performed at day seven. We analyzed the presence and extent of thrombotic occlusion, the vascular stricture, the arterioportal shunt, and the presence of an intra-abdominal hemorrhage. We applied Fisher's exact test to compare the complication rate between the two groups; a value was considered statistically significant if the p-value was less than 0.05. In the group I animals (n = 11), three had complete thrombotic occlusion of the portal vein. Among these three animals, one had a segmental infarction, and one animal showed a partial occlusion. In the group II animals (n = 16), complications were not identified. Statistical analysis revealed the complication rate of group I was significantly higher than that of group II ({rho} = .019). The portal vein occlusion rate was significantly higher in the portal vein penetrating group than in the non-penetrating group.

  16. Image-guided multipolar radiofrequency ablation of liver tumours: initial clinical results

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    Terraz, Sylvain; Constantin, Christophe; Becker, Christoph D. [Geneva University Hospital, Department of Radiology, Geneva 14 (Switzerland); Majno, Pietro Edoardo; Mentha, Gilles [Geneva University Hospital, Department of Surgery, Geneva 14 (Switzerland); Spahr, Laurent [Geneva University Hospital, Department of Gastroenterology, Geneva 14 (Switzerland)

    2007-09-15

    The local effectiveness and clinical usefulness of multipolar radiofrequency (RF) ablation of liver tumours was evaluated. Sixty-eight image-guided RF sessions were performed using a multipolar device with bipolar electrodes in 53 patients. There were 45 hepatocellular carcinomas (HCC) and 42 metastases with a diameter {<=}3 cm (n = 55), 3.1-5 cm (n = 29) and >5 cm (n = 3); 26 nodules were within 5 mm from large vessels. Local effectiveness and complications were evaluated after RF procedures. Mean follow-up was 17 {+-} 10 months. Recurrence and survival rates were analysed by the Kaplan-Meier method. The primary and secondary technical effectiveness rate was 82% and 95%, respectively. The major and minor complication rate was 2.9%, respectively. The local tumour progression at 1- and 2-years was 5% and 9% for HCC nodules and 17% and 31% for metastases, respectively; four of 26 nodules (15%) close to vessels showed local progression. The survival at 1 year and 2 years was 97% and 90% for HCC and 84% and 68% for metastases, respectively. Multipolar RF technique creates ablation zones of adequate size and tailored shape and is effective to treat most liver tumours, including those close to major hepatic vessels. (orig.)

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Daniels, Matthew J.; Varghese, Tomy

    2010-08-01

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

  19. Clinical significance of vagus nerve variation in radiofrequency ablation of thyroid nodules

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    Ha, Eun Ju; Baek, Jung Hwan; Lee, Jeong Hyun; Shong, Young Kee [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Kim, Jae Kyun [Chung-Ang University College of Medicine, Department of Radiology, Seoul (Korea, Republic of)

    2011-10-15

    To evaluate the types and incidence of vagus nerve variations and to assess factors related to the vulnerability of vagus nerves during the radiofrequency (RF) ablation of thyroid nodules. Bilateral vagus nerves of 304 consecutive patients who underwent ultrasound of the neck were assessed. Two radiologists evaluated vagus nerve type (types 1-4; lateral/anterior/medial/posterior), the shortest distance between the thyroid gland and vagus nerve, and thyroid contour. Vagus nerve vulnerability was defined as a vagus nerve located within 2 mm of the thyroid gland through the ex vivo experiments, and factors associated with vulnerability were assessed. We were unable to find one vagus nerve. Of the 607 vagus nerves, 467 (76.9%) were type 1, 128 (21.1%) were type 2, 10 (1.6%) were type 3, and 2 (0.3%) were type 4, with 81 (13.3%) being vulnerable. Univariate analysis showed that sex, location, thyroid contour and type were significantly associated with vagus nerve vulnerability. Multivariate analysis showed that bulging contour caused by thyroid nodules (P = 0.001), vagus nerve types 2/4 (P < 0.001) and type 3 (P < 0.001) were independent predictors. The operator should pay attention to anatomical variations and the resulting vagus nerve injury during RF ablation of bulging thyroid nodules. (orig.)

  20. A randomized prospective long-term (>1 year) clinical trial comparing the efficacy and safety of radiofrequency ablation to 980 nm laser ablation of the great saphenous vein.

    Science.gov (United States)

    Sydnor, Malcolm; Mavropoulos, John; Slobodnik, Natalia; Wolfe, Luke; Strife, Brian; Komorowski, Daniel

    2017-07-01

    Purpose To compare the short- and long-term (>1 year) efficacy and safety of radiofrequency ablation (ClosureFAST™) versus endovenous laser ablation (980 nm diode laser) for the treatment of superficial venous insufficiency of the great saphenous vein. Materials and methods Two hundred patients with superficial venous insufficiency of the great saphenous vein were randomized to receive either radiofrequency ablation or endovenous laser ablation (and simultaneous adjunctive therapies for surface varicosities when appropriate). Post-treatment sonographic and clinical assessment was conducted at one week, six weeks, and six months for closure, complications, and patient satisfaction. Clinical assessment of each patient was conducted at one year and then at yearly intervals for patient satisfaction. Results Post-procedure pain ( p ablation group. Improvements in venous clinical severity score were noted through six months in both groups (endovenous laser ablation 6.6 to 1; radiofrequency ablation 6.2 to 1) with no significant difference in venous clinical severity score ( p = 0.4066) or measured adverse effects; 89 endovenous laser ablation and 87 radiofrequency patients were interviewed at least 12 months out with a mean long-term follow-up of 44 and 42 months ( p = 0.1096), respectively. There were four treatment failures in each group, and every case was correctable with further treatment. Overall, there were no significant differences with regard to patient satisfaction between radiofrequency ablation and endovenous laser ablation ( p = 0.3009). There were no cases of deep venous thrombosis in either group at any time during this study. Conclusions Radiofrequency ablation and endovenous laser ablation are highly effective and safe from both anatomic and clinical standpoints over a multi-year period and neither modality achieved superiority over the other.

  1. Insufficient radiofrequency ablation promotes angiogenesis of residual hepatocellular carcinoma via HIF-1α/VEGFA.

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    Jian Kong

    Full Text Available 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.

  2. The impact of general anesthesia on radiofrequency ablation of hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Yuan-Hung Kuo

    2014-11-01

    Full Text Available This study investigates the impact of general anesthesia (GA on percutaneous radiofrequency ablation (RFA of hepatocellular carcinoma (HCC. A total of 118 treatment-naïve HCC patients in Barcelona Clinic Liver Cancer curative stage were enrolled. Patients who underwent RFA with GA were designated as the GA group, and the others were identified as the non-GA group. All the percutaneous RFA procedures were performed by the same hepatologist. The GA group comprised 42 (44.1% patients with 71 tumors (mean size, 2.53 cm and the non-GA group had 66 patients (55.9% with 90 tumors (mean size, 2.35 cm. Complete tumor ablation was achieved after one session in 92.3% of the 52 GA patients, and after one to three sessions in 92.4% of 66 non-GA patients. The GA group required significantly fewer RFA sessions to obtain a similar treatment effect (p < 0.001 and the duration of hospitalization was also shortened among the GA patients (4.4 ± 0.9 days vs. 5.1 ± 1.9 days, p = 0.044. The 2-year overall survival and recurrence-free survival rates were not significantly different between the two groups. Overall, performing RFA with GA can decrease the number of sessions required to achieve complete tumor ablation in early stage HCC patients and shorten the hospitalization duration.

  3. Direct current combined with bipolar radiofrequency ablation: an ex vivo feasibility study.

    Science.gov (United States)

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

    2011-06-01

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

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    Gupta, Pushpender, E-mail: pugupta@wakehealth.edu; Allen, Brian C., E-mail: bcallen2@wakehealth.edu; Chen, Michael Y., E-mail: mchen@wakehealth.edu; Childs, David D., E-mail: dchilds@wakehealth.edu; Kota, Gopi, E-mail: gkota@wakehealth.edu; Zagoria, Ronald J., E-mail: rzagoria@wakehealth.edu [Wake Forest University School of Medicine, Department of Radiology (United States)

    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.

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

    Science.gov (United States)

    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.

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

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    Tanaka, Toshihiro, E-mail: toshihir@bf6.so-net.ne.jp [Nara Medical University, Department of Radiology (Japan); Isfort, Peter, E-mail: isfort@hia.rwth-aachen.de [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany); Braunschweig, Till, E-mail: tbraunschweig@ukaachen.de; Westphal, Saskia, E-mail: swestphal@ukaachen.de [RWTH Aachen University, Department of Pathology, Aachen University Hospital (Germany); Woitok, Anna, E-mail: awoitok@ukaachen.de [RWTH Aachen University, Institute for Laboratory Animal Science (Germany); Penzkofer, Tobias, E-mail: penzkofer@rad.rwth-aachen.de; Bruners, Philipp, E-mail: bruners@rad.rwth-aachen.de [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany); Kichikawa, Kimihiko, E-mail: kkichika@naramed-u.ac.jp [Nara Medical University, Department of Radiology (Japan); Schmitz-Rode, Thomas, E-mail: smiro@hia.rwth-aachen.de; Mahnken, Andreas H., E-mail: mahnken@rad.rwth-aachen.de [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany)

    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.

  7. Osteoid osteoma treated with percutaneous radiofrequency ablation: MR imaging follow-up

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    Lee, Min Hee [Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 108 Pyung-dong, Jongro-gu, Seoul 110-746 (Korea, Republic of)], E-mail: min.h.lee@samsung.com; Ahn, Joong Mo; Chung, Hye Won; Lim, Hyo K.; Suh, Jae Gon; Kwag, Hyon Joo; Hong, Hyun Pyo; Kim, Byung Moon [Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 108 Pyung-dong, Jongro-gu, Seoul 110-746 (Korea, Republic of)

    2007-11-15

    Purpose: We evaluated follow-up magnetic resonance (MR) images for osteoid osteoma treated with percutaneous radiofrequency ablation (RFA). Materials and methods: Sixteen patients with osteoid osteoma treated with RFA underwent follow-up MR imaging. The protocol included T1, T2 and contrast-enhanced (CE) T1-weighted images with fat saturation at each visit immediately for 17 months after the treatment. MR images were jointly reviewed by two radiologists, regarding the appearance of treated areas, presence of complications, and the best sequence for visualization of signal intensity (SI) changes. The therapeutic response was evaluated to be a clinical success with the relief of pain. Results: The treated areas had a target-like appearance on MR images: a central ablated zone (Z1) surrounded by a band (Z2), and a peripheral area (Z3). Z1 was a non-enhancing, hypointense core on T1, T2WI. Z2 was a well-enhancing, hyperintense rim on T2WI. Z3 was less hyperintense and less enhanced than Z2. All nidi were within Z1. This appearance became evident from 1 week to 1 and 2 months. Following up after 2 months, Z2 showed progressive inward enhancement from the periphery, resulting in almost complete enhancement of Z1 and Z2 with a diminishing size. Z3 gradually showed a decrease in signal change and enhancement. No complications were found. CE-T1WI was the best for visualizing SI changes. The clinical success was achieved in all patients except for one patient with a recurrence at 17 months following treatment that had a second ablation. Conclusion: MR imaging demonstrated a characteristic appearance and subsequent changes of treated areas for osteoid osteoma following RFA.

  8. Ablative safety margin depicted by fusion imaging with post-treatment contrast-enhanced ultrasound and pre-treatment CECT/CEMRI after radiofrequency ablation for liver cancers.

    Science.gov (United States)

    Bo, Xiao-Wan; Xu, Hui-Xiong; Guo, Le-Hang; Sun, Li-Ping; Li, Xiao-Long; Zhao, Chong-Ke; He, Ya-Ping; Liu, Bo-Ji; Li, Dan-Dan; Zhang, Kun; Wang, Dan

    2017-10-01

    To evaluate the value of fusion imaging with post-treatment contrast-enhanced ultrasound (CEUS) and pre-treatment contrast-enhanced CT/MRI (CECT/CEMRI) in evaluating ablative safety margin after percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) for liver cancers. 34 consecutive patients with 47 liver lesions who had undergone RFA were included. Fusion imaging with post-treatment CEUS and pre-treatment CECT/CEMRI was carried out to evaluate local treatment response and ablative safety margin within 1-3 days after RFA. The minimal ablative safety margins of the ablation zones were recorded. The complete response (CR) rate was calculated with reference to CECT/CEMRI results 1 month after RFA. The local tumour progression (LTP) was also recorded. Of the 47 ablation zones, 47 (100%) were clearly depicted with CEUS-CECT/CEMRI fusion imaging, 36 (76.6%) with US-CECT/CEMRI fusion imaging and 21 (44.7%) with conventional US (both p ablative safety margins were great than or equal to 5 mm in 28 ablation zones, between 0 and 5 mm in 15, and less than 0 mm in 4. For the four lesions without enough ablative safety margin, three were referred to follow-up because CEUS showed larger ablation zones than pre-treatment lesions and the remaining lesion was subject to additional RFA 5 days after the first RFA. The CR rate was 95.7% (45/47) with reference to CECT/CEMRI results 1 month after RFA. During 2 to 34 months follow-up, LTP was found in two (4.4%) of 45 lesions with CR. Insufficient ablative safety margin was more commonly found in those lesions with LTP than those without LTP (1/4 vs 1/43, p ablative safety margin accurately after RFA. Inadequate ablative safety margin is associated with LTP. Depiction of ablative safety margin by fusion imaging after ablation might be considered as a routine procedure to assess the treatment response of RFA. Advances in knowledge: Fusion imaging with post-treatment CEUS and pre-treatment CECT/CEMRI is an effective method to

  9. Monitoring radiofrequency ablation using real-time ultrasound Nakagami imaging combined with frequency and temporal compounding techniques.

    Directory of Open Access Journals (Sweden)

    Zhuhuang Zhou

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

  10. The minimal ablative margin of radiofrequency ablation of hepatocellular carcinoma (> 2 and < 5 cm) needed to prevent local tumor progression: 3D quantitative assessment using CT image fusion.

    Science.gov (United States)

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

    2010-09-01

    The aim of this study was to elucidate the minimal ablative margin for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) (> 2 and ablative margin quantitatively. Risk factors for local tumor progression (the thinnest ablative margin, tumor size, and the effect of hepatic vessels) were assessed by multivariate analysis. Patients underwent follow-up for 12.9-46.6 months (median, 28.1 months). The tumors were 2.1-4.8 cm (mean +/- SD, 2.7 +/- 0.6 cm) in diameter. The thinnest ablative margins ranged from 0 to 6 mm (1.0 +/- 1.4 mm). A 5-mm safety margin was achieved in only 2.7% (3/110) of cases. In 47.3% (52/110) of cases, vessel-induced indentation of the ablation zone contributed to the thinnest ablative margins. Local tumor progression was detected in 27.3% (30/110) of cases. Concordance between local tumor progression and the thinnest margin was observed in 83.3% (25/30) of cases. The incidence of concordant local tumor progression was 22.7% (25/110), 18.9% (10/53), 5.9% (2/34), and 0% (0/15) in tumors with the thinnest ablative margin of > or = 0, > or = 1, > or = 2, and > or = 3 mm, respectively. An insufficient ablative margin was the sole significant factor associated with local tumor progression. When the thickness of the ablative margin is evaluated by CT image fusion, a margin of 3 mm or more appears to be associated with a lower rate of local tumor progression after percutaneous RFA of HCC.

  11. [Intraoperative treatment for atrial fibrillation using bi-polar radiofrequency ablation system: a clinical report of 91 cases].

    Science.gov (United States)

    Cui, Yong-qiang; Meng, Xu; Li, Yan; Wang, Jian-gang; Zeng, Wen; Gao, Feng; Xu, Chun-lei

    2009-04-01

    To observe the short and mid-term therapeutic effects of Bi-polar ablation systems for intraoperative treatment of atrial fibrillation (AF). From March 2005 to January 2007, 91 patients received intraoperative treatment of atrial fibrillation with Bi-polar ablation systems, including 5 cases of paroxysmal atrial fibrillation and 86 persistent/permanent cases. The main concomitant heart diseases were rheumatic mitral valve diseases. Atricure Dry Ablation System was used for 37 cases and Cardioblate Irrigated Ablation System for 54 cases. The ablation lesion patterns included Cox-maze III, Modified Cox Mini-maze and Left-sided Maze. Mean ablation time was (14.1+/-6.7) min. No ablation-related complications occurred. Three patients died perioperatively. Two patients had permanent pacemaker implantation 3 months after operation. One case suffered from stroke and lower limb thrombosis 2.5 years after operation. Follow-up lasted for 6 to 29 months. The none-AF rhythm were 62.5%, 85.2%, 79.0% and 74.5% at discharge, 3 months, 6 months, and>or=12 months respectively. Compared to Uni-polar Ablation therapy group, the restoration of sinus rhythm in Bi-polar group were significantly higher at 6 months and>or=12 months postoperatively. The latest follow-up results indicated that 100% of preoperative paroxysmal atrial fibrillation patients restored sinus rhythm and 75.3% of persistent/permanent patients were free from atrial fibrillation. The none-AF rhythm of Atricure group (81.1%) showed no difference from the Cardioblate (77.5%). Meanwhile there were no significant differences among the three ablation lesion groups. Intraoperative radiofrequency ablation with Bi-polar systems is a feasible, safe and highly effective surgical option compared to the Uni-polar ablation technique.

  12. Aspirin in Preventing Disease Recurrence in Patients With Barrett Esophagus After Successful Elimination by Radiofrequency Ablation | Division of Cancer Prevention

    Science.gov (United States)

    This randomized phase II trial studies the safety of and how well aspirin works in preventing Barrett's esophagus from returning after it has been successfully eliminated by radiofrequency ablation. Studying samples of tissue from patients with Barrett's esophagus for the levels of a specific protein that is linked to developing Barrett's esophagus may help doctors learn whether aspirin can prevent it from returning after it has been successfully treated. |

  13. Iatrogenic intra-atrial macro-reenterant tachycardia following transcatheter closure of atrial septal defect treated by radiofrequency ablation

    Directory of Open Access Journals (Sweden)

    Ibrahim Marai

    2011-01-01

    Full Text Available Percutaneous closure of an atrial septal defect (ASD has been established as a safe and effective alternative to surgical management. We describe a case of a 41-year-old patient in whom an Amplatzer septal occluder device was used to close a moderately large ASD and who subsequently developed incessant intra-atrial macro-reenterant tachycardia. The tachycardia was terminated by radiofrequency ablation guided by electroanatomical mapping.

  14. Assessing Temperature-Controlled Radiofrequency Tonsil Ablation for Treatment of Halitosis Caused by Chronic Tonsillitis with Caseum

    Directory of Open Access Journals (Sweden)

    F. Hashemian

    2015-10-01

    Full Text Available Introduction & Objective: Chronic tonsillitis with caseum has been proven to be the cause of halitosis. The objective of this study was to evaluate the efficacy and safety of temperature-controlled radiofrequency tonsil ablation in the treatment of halitosis caused by chronic tonsil-litis with caseum. Materials & Methods: In this clinical trial study 28 adult patients with halitosis due to chronic tonsillitis with caseum were treated by temperature-controlled radiofrequency tonsil ablation and efficacy and complications of procedure were recorded and the data were analyzed by Spss software and paired t-test. Results: The difference between the amount of halitosis was statistically significant before and after the procedure (P <0.001. Patients’ pain were mild to moderate .Mild bleeding occurred in 21% of patients and 79% had no bleeding. In average 3.14 days after the procedure patients tolerated regular diet and after 1.96 days they could do their daily routines. Conclusion: Temperature-controlled radiofrequency tonsil ablation is a safe and effective method for treatment of halitosis due to chronic tonsillitis with caseum and have several ad-vantages compared to conventional tonsillectomy such as reduced post-operative pain and bleeding, shorter recovery time and convenience of an office procedure. (Sci J Hamadan Univ Med Sci 2015; 22 (3: 179-186

  15. Impact of irrigation flow rate and intrapericardial fluid on cooled-tip epicardial radiofrequency ablation.

    Science.gov (United States)

    Aryana, Arash; O'Neill, Padraig Gearoid; Pujara, Deep K; Singh, Steve K; Bowers, Mark R; Allen, Shelley L; d'Avila, André

    2016-08-01

    The optimal irrigation flow rate (IFR) during epicardial radiofrequency (RF) ablation has not been established. This study specifically examined the impact of IFR and intrapericardial fluid (IPF) accumulation during epicardial RF ablation. Altogether, 452 ex vivo RF applications (10 g for 60 seconds) delivered to the epicardial surface of bovine myocardium using 3 open-irrigated ablation catheters (ThermoCool SmartTouch, ThermoCool SmartTouch-SF, and FlexAbility) and 50 in vivo RF applications delivered (ThermoCool SmartTouch-SF) in 4 healthy adult swine in the presence or absence of IPF were examined. Ex vivo, RF was delivered at low (≤3 mL/min), reduced (5-7 mL/min), and high (≥10 mL/min) IFRs using intermediate (25-35 W) and high (35-45 W) power. In vivo, applications were delivered (at 9.3 ± 2.2 g for 60 seconds at 39 W) using reduced (5 mL/min) and high (15 mL/min) IFRs. Ex vivo, surface lesion diameter inversely correlated with IFR, whereas maximum lesion diameter and depth did not differ. While steam pops occurred more frequently at low IFR using high power (ThermoCool SmartTouch and ThermoCool SmartTouch-SF), tissue disruption was rare and did not vary with IFR. In vivo, charring/steam pop was not detected. Although there were no discernible differences in lesion size with IFR, surface lesion diameter, maximum diameter, depth, and volume were all smaller in the presence of IPF at both IFRs. Cooled-tip epicardial RF ablation created using reduced IFRs (5-7 mL/min) yields lesion sizes similar to those created using high IFRs (≥10 mL/min) without an increase in steam pop/tissue disruption, whereas the presence of IPF significantly reduces the lesion size. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  16. The Results of Ultrasonography-Guided Percutaneous Radiofrequency Ablation in Hyperparathyroid Patients in Whom Surgery Is Not Feasible

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    Sormaz, Ismail Cem, E-mail: icsormaz@gmail.com [Istanbul University, Istanbul Faculty of Medicine, Department of General Surgery (Turkey); Poyanlı, Arzu, E-mail: arzupoyanli@yahoo.com [Istanbul University, Istanbul Faculty of Medicine, Department of Radiology (Turkey); Açar, Sami, E-mail: acarrsami@gmail.com [Istanbul University, Istanbul Faculty of Medicine, Department of General Surgery (Turkey); İşcan, Ahmet Yalın, E-mail: yaliniscan@gmail.com [Fatih Sultan Mehmet Research and Education Hospital, Department of General Surgery (Turkey); Ozgur, İlker, E-mail: dr.ilkerozgur@gmail.com; Tunca, Fatih, E-mail: drfatihtunca@yahoo.com; Senyürek, Yasemin Giles, E-mail: yasemin.senyurek@gmail.com [Istanbul University, Istanbul Faculty of Medicine, Department of General Surgery (Turkey)

    2017-04-15

    BackgroundThe aim of the study was to evaluate the results of ultrasonography (US)-guided percutaneous radiofrequency ablation (RFA) in hyperparathyroid patients who refused surgery or had high surgical risks.Patients and MethodsFive patients with hyperparathyroidism (HPT) underwent US-guided RFA for a single hyperfunctioning parathyroid lesion. Post-ablation serum calcium and parathormone (PTH) assays were performed. All patients underwent imaging studies 6 months after the ablation to visualize the post-ablation change in the size of the treated parathyroid lesions.ResultsAll patients were normocalcemic on the post-ablation 1st day and 6th month. The post-ablation PTH levels were normal in three patients but remained elevated in two patients. The size of the parathyroid lesion was ≥30 mm in the two patients with elevated PTH, whereas the lesion was smaller than 30 mm in those with normal post-ablation PTH values.ConclusionAlthough this is a limited case series, it demonstrates the potential feasibility of RFA for HPT. Benefits were achieved particularly in patients with small parathyroid lesions.

  17. The contemporary role of ablative treatment approaches in the management of renal cell carcinoma (RCC): focus on radiofrequency ablation (RFA), high-intensity focused ultrasound (HIFU), and cryoablation.

    Science.gov (United States)

    Klatte, Tobias; Kroeger, Nils; Zimmermann, Uwe; Burchardt, Martin; Belldegrun, Arie S; Pantuck, Allan J

    2014-06-01

    Currently, most of renal tumors are small, low grade, with a slow growth rate, a low metastatic potential, and with up to 30 % of these tumors being benign on the final pathology. Moreover, they are often diagnosed in elderly patients with preexisting medical comorbidities in whom the underlying medical conditions may pose a greater risk of death than the small renal mass. Concerns regarding overdiagnosis and overtreatment of patients with indolent small renal tumors have led to an increasing interest in minimally invasive, ablative as an alternative to extirpative interventions for selected patients. To provide an overview about the state of the art in radiofrequency ablation (RFA), high-intensity focused ultrasound, and cryoablation in the clinical management of renal cell carcinoma. A PubMed wide the literature search of was conducted. International consensus panels recommend ablative techniques in patients who are unfit for surgery, who are not considered candidates for or elect against elective surveillance, and who have small renal masses. The most often used techniques are cryoablation and RFA. These ablative techniques offer potentially curative outcomes while conferring several advantages over extirpative surgery, including improved patient procedural tolerance, faster recovery, preservation of renal function, and reduction in the risk of intraoperative and postsurgical complications. While it is likely that outcomes associated with ablative modalities will improve with further advances in technology, their application will expand to more elective indications as longer-term efficacy data become available. Ablative techniques pose a valid treatment option in selected patients.

  18. Percutaneous radiofrequency ablation of lung tumors: evaluation of the literature using evidence-based techniques.

    LENUS (Irish Health Repository)

    Chan, Victoria O

    2012-02-01

    PURPOSE: The aim of this study was to evaluate the literature for articles assessing radiofrequency ablation (RFA) for pulmonary malignancy. MATERIALS AND METHODS: The "bottom-up" approach to evidence-based practice was applied by 2 reviewers to the retrieval and appraisal of original research articles published on pulmonary RFA between 2002 and 2009. Primary lung cancer and pulmonary metastases data were analyzed separately. The relationship between the percentage of local recurrence rate and lesion size, patient age, follow-up duration, and time to local recurrence was assessed using Spearman\\'s rank correlation. Discrete time series were used to evaluate time trends. RESULTS: Secondary evidence yielded 1 review of 26 observational studies. Primary evidence yielded 46 studies that seemed suitable for detailed appraisal. A total of 2905 ablations were performed in 1584 patients. Eight studies evaluated primary lung cancers alone, 11 evaluated pulmonary metastases alone, 25 evaluated both, and 2 did not specify the histology. Results revealed trends toward increasing use of conscious sedation over general anesthesia, increasing use of multitined probes, decreasing size of nodule selection, and use of positron emission tomography\\/computed tomography as the optimal follow-up tool. Mean morbidity was 24.6%. The most prevalent side effects included pneumothorax (28.3%), pleural effusions (14.8%), and pain (14.1%). Procedure-related mortality ranged from 0 to 5.6, with an overall procedure-related mortality rate of 0.21%. There were 282 (12.2%) local recurrences occurring at a mean of 13 months. The mean overall survival rate was 59.4%, and the cancer-specific survival rate was 82.6%. CONCLUSIONS: This evidence-based practice review of pulmonary RFA shows it to be a promising treatment for pulmonary malignancy in carefully selected patient populations. Studies with higher levels of evidence, including case-control, prospective nonrandomized and randomized trials

  19. Minimal vascular flows cause strong heat sink effects in hepatic radiofrequency ablation ex vivo.

    Science.gov (United States)

    Lehmann, Kai S; Poch, Franz G M; Rieder, Christian; Schenk, Andrea; Stroux, Andrea; Frericks, Bernd B; Gemeinhardt, Ole; Holmer, Christoph; Kreis, Martin E; Ritz, Jörg P; Zurbuchen, Urte

    2016-08-01

    The present paper aims to assess the lower threshold of vascular flow rate on the heat sink effect in bipolar radiofrequency ablation (RFA) ex vivo. Glass tubes (vessels) of 3.4 mm inner diameter were introduced in parallel to bipolar RFA applicators into porcine liver ex vivo. Vessels were perfused with flow rates of 0 to 1,500 ml/min. RFA (30 W power, 15 kJ energy input) was carried out at room temperature and 37°C. Heat sink effects were assessed in RFA cross sections by the decrease in ablation radius, area and by a high-resolution sector planimetry. Flow rates of 1 ml/min already caused a significant cooling effect (P ≤ 0.001). The heat sink effect reached a maximum at 10 ml/min (18.4 mm/s) and remained stable for flow rates up to 1,500 ml/min. Minimal vascular flows of ≥1 ml/min cause a significant heat sink effect in hepatic RFA ex vivo. A lower limit for volumetric flow rate was not found. The maximum of the heat sink effect was reached at a flow rate of 10 ml/min and remained stable for flow rates up to 1,500 ml/min. Hepatic inflow occlusion should be considered in RFA close to hepatic vessels. © 2016 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

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

    Science.gov (United States)

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

    2008-01-01

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

  1. Percutaneous CT-guided radiofrequency ablation of solitary small renal masses. A single center experience

    Energy Technology Data Exchange (ETDEWEB)

    Pieper, C.C.; Fischer, S.; Strunk, H.; Meyer, C.; Thomas, D.; Willinek, W.A.; Schild, H. [Univ. Bonn (Germany). Dept. of Radiology; Hauser, S. [Univ. Bonn (Germany). Dept. of Urology; Nadal, J. [Univ. Bonn (Germany). Inst. for Medical Biometry; Wilhelm, K. [Johanniter Hospital Bonn (Germany). Dept. of Radiology

    2015-07-15

    To analyze the outcome of patients undergoing percutaneous CT-guided radiofrequency ablation (RFA) of small renal masses (SRM) at a single center during a ten-year time period. Patient records of renal RFAs (07/2003 - 11/2013) were reviewed. Indications were SRM suspicious of malignancy on imaging and one of the following: severe comorbidity; old age; solitary kidney; impaired renal function; patient wish. Biopsy was performed at the time of RFA. Patients were excluded if no follow-up was available. Patient and procedural characteristics were recorded. Survival rates were calculated using the Kaplan-Meier's method and compared with log-rank or cox tests. 38 patients (16 females, mean age 70.0 years [range 52 - 87]) presenting with a solitary SRM were included in the study. Biopsy showed malignancy in 29 patients; 9 had benign tumors. 26 patients suffered from cardiovascular, respiratory or hepatic comorbidities. Technical success (complete ablation on first follow-up) was achieved in 95 % of cases. Two major complications (bowel perforation; hematothorax) occurred. The 3- and 7-year overall survival (OS) [any cause] rates were 73.4 ± 0.8 % and 50.3 ± 1.0 %, respectively (mean follow-up 54.6 months, range 1 - 127). 4 recurrences and 2 metastases were observed. The presence of comorbidities was the only independent predictor of OS. There was no difference in survival between patients with benign and malignant tumors. RFA of SRM is successful in a large percentage of cases with a low complication rate and durable local control. As RFA is typically performed in multimorbid patients, overall survival seems to depend primarily on comorbidities rather than cancer progression.

  2. Therapeutic outcome of CT-guided radiofrequency ablation in patients with osteoid osteoma

    Energy Technology Data Exchange (ETDEWEB)

    Lassalle, Louis; Campagna, R.; Corcos, G.; Feydy, A. [Hopital Cochin-APHP Paris Universite Paris Descartes, Service de Radiologie Osteo-Articulaire, Paris (France); Babinet, A. [Hopital Cochin-APHP Paris Universite Paris Descartes, Service de Chirurgie Orthopedique, Paris (France); Larousserie, F. [Hopital Cochin-APHP Paris Universite Paris Descartes, Service d' Anatomo-Pathologie, Paris (France); Stephanazzi, J. [Hopital Cochin-APHP Paris Universite Paris Descartes, Service d' Anesthesie, Paris (France)

    2017-07-15

    To assess the long-term outcome of computed tomography-guided radiofrequency ablation (CT-guided RFA) in patients with suspected osteoid osteoma (OO). Single-center retrospective study. Patients with clinical suspicion and imaging diagnosis of osteoid osteoma were treated by CT-guided RFA using the same device with either a 7- or 10-mm active tip electrode. Specific precautions were applied in case of articular or spinal OO. Patients were contacted by phone to evaluate the long-term outcome in terms of pain, ability to perform daily activities (including sports), and long-term complications. Success was defined as the absence of residual pain and ability to perform daily activities normally. From 2008 to 2015, 126 patients were treated by CT-guided RFA for OO in our institution. Mean patient age was 26.1 years (SD = 11, range 1-53); mean delay to diagnosis was 16.9 months (SD = 15.2, range 1-120). Among patients who answered the follow-up call (n = 88), the overall success rate was 94.3%: 79/88 (89.8%) had primary success of the procedure, and 4/88 (4.5%) had a secondary success (repeat-RFA after pain recurrence). Mean follow-up time was 34.6 months (SD = 24.7, range 3-90). Few complications occurred: two mild reversible peripheral nerve injuries, one brachial plexus neuropathy, one broken electrode tip fragment, and one muscular hematoma. Osteoid osteoma can be effectively and safely treated by CT-guided RFA using the presented ablation protocol. Beneficial effects of the treatment persist at long-term follow-up. (orig.)

  3. Intraductal Cooling via a Nasobiliary Tube During Radiofrequency Ablation of Central Liver Tumors Reduces Biliary Injuries.

    Science.gov (United States)

    Felker, Ely R; Lee-Felker, Stephanie A; Ajwichai, Khobkhoon; Tan, Nelly; Lu, David S; Durazo, Francisco A; Raman, Steven S

    2015-06-01

    The objective of our study was to determine the safety and efficacy of intraductal perfusion of chilled 5% dextrose in water (D5W) via an endoscopic nasobiliary tube (NBT) for the prevention of thermal bile duct injury in patients undergoing percutaneous radiofrequency ablation (RFA) of central liver tumors. We performed a retrospective study comparing outcomes of 32 consecutive patients who underwent percutaneous RFA of central liver tumors without intraductal perfusion of chilled D5W (control cohort) and 14 consecutive patients who underwent temporary intraductal perfusion of chilled D5W at 2 mL/s via endoscopic NBT placement before RFA (endoscopic NBT cohort). The primary and secondary outcomes were the rate of biliary complications and local tumor progression, respectively. All patients tolerated the procedures well. There was a significantly lower rate of biliary complications in the endoscopic NBT cohort (0/14 patients, 0%) than in the control cohort (10/32 patients, 31%) (p NBT cohort (12/14 patients, 86%) compared with the control cohort (20/32 patients, 62%) (p = 0.05). There was no difference in the rate of local tumor progression between the endoscopic NBT cohort (4/19 tumors, 21%) and the control cohort (9/39 tumors, 23%) (p = 1.0). Perfusion of chilled water through an endoscopic NBT helps prevent thermal biliary injury during RFA of central liver tumors without increasing rates of local tumor progression.

  4. Comparison of Noninvasive High-Intensity Focused Ultrasound with Radiofrequency Ablation of Osteoid Osteoma.

    Science.gov (United States)

    Sharma, Karun V; Yarmolenko, Pavel S; Celik, Haydar; Eranki, Avinash; Partanen, Ari; Smitthimedhin, Anilawan; Kim, Aerang; Oetgen, Matthew; Santos, Domiciano; Patel, Janish; Kim, Peter

    2017-11-01

    To evaluate clinical feasibility and safety of magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) treatment of symptomatic osteoid osteoma and to compare clinical response with standard of care treatment. Nine subjects with radiologically confirmed, symptomatic osteoid osteoma were treated with MR-HIFU in an institutional review board-approved clinical trial. Treatment feasibility and safety were assessed. Clinical response was evaluated in terms of analgesic requirement, visual analog scale pain score, and sleep quality. Anesthesia, procedure, and recovery times were recorded. This MR-HIFU group was compared with a historical control group of 9 consecutive patients treated with radiofrequency ablation. Nine subjects (7 male, 2 female; 16 ± 6 years) were treated with MR-HIFU without technical difficulties or any serious adverse events. There was significant decrease in their median pain scores 4 weeks within treatment (6 vs 0, P HIFU treatment of osteoid osteoma refractory to medical therapy is feasible and can be performed safely in pediatric patients. Clinical response is comparable with standard of care treatment but without any incisions or exposure to ionizing radiation. ClinicalTrials.govNCT02349971. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Glomerular Loss After Renal Radiofrequency Ablation Are Comparable to 30 Minutes of Warm Ischemia.

    Science.gov (United States)

    Abreu, Leonardo Albuquerque Dos Santos; Damasceno-Ferreira, José Aurelino; Costa, Waldemar Silva; Pereira-Sampaio, Marco Aurélio; Sampaio, Francisco José Barcellos; de Souza, Diogo Benchimol

    2017-05-01

    To compare, with stereological methods, the glomerular loss in kidneys submitted to radiofrequency ablation (RFA) or warm ischemia. Twenty-six male pigs were divided into three groups. Eight animals were allocated in the sham group, which was submitted to laparoscopic dissection of the left renal hilum, without renal ischemia. Eight animals were allocated in the ischemia group, which had the left renal hilum clamped for 30 minutes under laparoscopic access. Ten animals were submitted to RFA of the left kidney lower pole, under laparoscopic visualization. Animals were euthanized 21 days after surgery, when kidneys were collected. Fragments of the upper pole of the left kidney were processed for morphometric analysis. Right kidney was used as self-controls for each animal. Glomerular volumetric density (Vv[glom]); volume-weighted glomerular volume (VWGV); and glomerular density were quantified by stereological methods and compared by Student's t-test and one-way-analysis of variance with Dunnett's post-test. Three animals in the RFA group developed postoperative complications (Urinoma/Hydronephrosis) and were excluded from the analysis. No difference was found among the kidneys submitted to RFA and warm ischemia for all parameters. However, these kidneys showed lower Vv[glom] and glomerular density when compared to its self-controls (right kidneys), and when compared to sham-operated animals (p comparable to that observed in kidneys submitted to 30 minutes of warm ischemia.

  6. Incidence of neuropathic pain after cooled radiofrequency ablation of sacral lateral branch nerves.

    Science.gov (United States)

    Stolzenberg, David; Gordin, Vitaly; Vorobeychik, Yakov

    2014-11-01

    To determine the incidence of neuropathic pain after cooled radiofrequency ablation (RFA) of the sacral lateral branches for the treatment of chronic posterior sacroiliac joint complex pain. Retrospective chart review of all patients with chronic posterior sacroiliac joint complex pain who underwent cooled RFA of the sacral lateral branches in our practice between July 2011 and February 2014. Single academic pain practice at a tertiary care medical center. Thirty-six patients with chronic posterior sacroiliac joint complex pain. All charts were reviewed to determine the procedure date, unilateral or bilateral, number of levels treated, and number of individual lesions. Side effects were assessed for their presence or absence, character, intensity, duration, and whether treatment was initiated or symptoms resolved spontaneously. Forty-eight separate procedures were performed, with a total of 193 levels and 430 lesions. Three patients had transient postprocedure neuropathic pain yielding a 0.7% (95% confidence interval [CI]± 0.4%) rate of this complication per lesion. This proportion increases to 6.2% (95% CI ± 3.5%) per procedure and to 9.4% (95% CI ± 5.2%) per patient. The incidence of postprocedural neuropathic pain after cooled RFA for posterior sacroiliac joint complex denervation is low and in a similar range to that in the lumbar spine. We consider this procedure safe to be utilized by pain medicine practitioners. Wiley Periodicals, Inc.

  7. In vitro evaluation of ice-cold saline irrigation during catheter radiofrequency ablation.

    Science.gov (United States)

    Squara, Fabien; Maeda, Shingo; Aldhoon, Bashar; Marginiere, Julie; Santangeli, Pasquale; Chik, William W; Michele, John; Zado, Erica; Marchlinski, Francis E

    2014-10-01

    Irrigated radiofrequency (RF) catheters allow tissue-electrode interface cooling, decreasing thrombus risk while enabling higher RF power delivery. The impact of irrigation with ice-cold saline (ICS) instead of conventional ambient-temperature saline (ATS) on lesion formation is unknown. We performed 120 RF ablations in vitro on porcine left ventricles, using ICS (saline at the catheter's tip. We applied 20 g of contact force, and delivered 20 W (irrigation 8 or 17 mL/min) or 30 W (irrigation 17 or 30 mL/min) RF power. Temperatures at tissue-electrode interface and 3-mm depth were assessed by fluoroptic probes. Lesion dimensions were assessed. ICS irrigation cooled the tissue-electrode interface better than ATS (53.9 ± 9.6 °C vs. 63 ± 11.4 °C, P saline volume load. However at lower RF power, ICS reduced lesion size compared to ATS. © 2014 Wiley Periodicals, Inc.

  8. Initial experience using a bipolar radiofrequency ablation device for hemostasis during thyroidectomy.

    Science.gov (United States)

    Baldwin, Keith; Haniff, Michelle; Somasundar, Ponnandai

    2013-01-01

    The purpose of this study was to evaluate a novel bipolar radiofrequency ablation (BRFA) device using nanotechnology for division of all named vessels during thyroidectomy. All thyroidectomies from January 2008 to July 2010 at a single institution used the BRFA device (EnSeal, Ethicon Endo-Surgery, Cincinnati, OH) for hemostasis. Clinicopathologic data and complications were recorded and compared with existing literature using other energy devices. Fifty-eight thyroidectomies were performed. Mean age was 54.7 years, and mean operating room time was 81 minutes. The average estimated blood loss was 46 mL. Ninety percent of patients were discharged in <23 hours. There were no hemorrhages. There was 1 recurrent laryngeal nerve (RLN) injury, and 1 case of transient hypocalcemia. This first small series using the BRFA device reveals initial safety and effectiveness for thyroid hemostasis, and warrants further study. The minimal thermal spread inherent in this device may make it an attractive option when structures such as the RLN may be near the zone of hemostasis. Copyright © 2011 Wiley Periodicals, Inc.

  9. Radiofrequency ablation of osteoid osteoma in common and technically challenging locations in pediatric population

    Directory of Open Access Journals (Sweden)

    Shaileshkumar Garge

    2017-01-01

    Full Text Available Context: Percutaneous radiofrequency ablation (RFA of osteoid osteoma has a high technical and clinical success rate. However, there is limited data on its use in the pediatric population, especially in technically challenging locations. Objective: To assess the safety and efficacy of computed tomography (CT-guided percutaneous RFA of osteoid osteoma in pediatric population. Patients and Methods: From June 2009 to May 2014, 30 patients with osteoid osteoma were treated with CT-guided RFA in common (25 cases and technically challenging (five cases: four near articular surface and one in sacrum locations. Therapy was performed under general anesthesia with a three-array expandable RF probe for 6 min at 90°C and power of 60–100 W. The patients were discharged next day under instruction. The treatment success was evaluated in terms of pain relief before and after (1 day, 1 month, and 6 months treatment. Results: Technical success was achieved in all patients (100%. Primary clinical success was 96.66% (29 of total 30 patients, despite the pediatric population and atypical location. One patient had persistent pain after 1 month and was treated successfully with a second procedure (secondary success rate was 100%. One patient had immediate complication of weakness of right hand and fingers extension. No delayed complications were observed. Conclusions: CT-guided RFA is relatively safe and highly effective for treatment of osteoid osteoma in pediatric population, even in technically difficult locations.

  10. A synchronous hepatocellular carcinoma and renal cell carcinoma treated with radio-frequency ablation

    Directory of Open Access Journals (Sweden)

    Yoon Serk Lee

    2014-09-01

    Full Text Available Radio-frequency ablation (RFA is a curative treatment for hepatocellular carcinoma (HCC. Percutaneous RFA has been shown to be beneficial for patients with small renal cell carcinoma (RCC lacking indications for resection. We experienced the case of a 53-year-old male who had conditions that suggested HCC, RCC, and alcoholic liver cirrhosis. Abdominal contrast-enhanced computed tomography (CT and magnetic resonance image showed liver cirrhosis with 2.8 cm ill-defined mass in segment 2 of the liver and 1.9 cm hypervascular mass in the left kidney. These findings were compatible with the double primary cancers of HCC and RCC. Transarterial chemoembolization (TACE was performed to treat the HCC. After the TACE, a focal lipiodol uptake defect was noticed on a follow up CT images and loco-regional treatment was recommended. Therefore, we performed RFAs to treat HCC and RCC. There was no evidence of recurrence in the follow up image after 1 month.

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

    Directory of Open Access Journals (Sweden)

    J R Doctor

    2016-01-01

    Full Text Available 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.

  12. Optical fiber sensors-based temperature distribution measurement in ex vivo radiofrequency ablation with submillimeter resolution

    Science.gov (United States)

    Macchi, Edoardo Gino; Tosi, Daniele; Braschi, Giovanni; Gallati, Mario; Cigada, Alfredo; Busca, Giorgio; Lewis, Elfed

    2014-11-01

    Radiofrequency thermal ablation (RFTA) induces a high-temperature field in a biological tissue having steep spatial (up to 6°C/mm) and temporal (up to 1°C/s) gradients. Applied in cancer care, RFTA produces a localized heating, cytotoxic for tumor cells, and is able to treat tumors with sizes up to 3 to 5 cm in diameter. The online measurement of temperature distribution at the RFTA point of care has been previously carried out with miniature thermocouples and optical fiber sensors, which exhibit problems of size, alteration of RFTA pattern, hysteresis, and sensor density worse than 1 sensor/cm. In this work, we apply a distributed temperature sensor (DTS) with a submillimeter spatial resolution for the monitoring of RFTA in porcine liver tissue. The DTS demodulates the chaotic Rayleigh backscattering pattern with an interferometric setup to obtain the real-time temperature distribution. A measurement chamber has been set up with the fiber crossing the tissue along different diameters. Several experiments have been carried out measuring the space-time evolution of temperature during RFTA. The present work showcases the temperature monitoring in RFTA with an unprecedented spatial resolution and is exportable to in vivo measurement; the acquired data can be particularly useful for the validation of RFTA computational models.

  13. Is percutaneous radiofrequency thermal ablation of hepatocellular carcinoma a safe procedure?

    Science.gov (United States)

    Zavaglia, Claudio; Corso, Rocco; Rampoldi, Antonio; Vinci, Maria; Belli, Luca Saverio; Vangeli, Marcello; Solcia, Marco; Castoldi, Chiara; Prisco, Cleofe; Vanzulli, Angelo; Pinzello, Giovambattista

    2008-03-01

    To assess the safety and efficacy of percutaneous radiofrequency thermal ablation (RFA) in the treatment of nonsurgical hepatocellular carcinoma (HCC) in daily practice. A total of 63 consecutive patients with HCC (solitary nodule electrical generator connected to an expandable 10-hook electrode. Seventy-one lesions were treated in 80 sessions. Sixteen patients required adjuvant chemoembolization. Mean follow-up was 18+/-12 months. An objective response was achieved in 87% of patients who underwent primary/adjuvant treatment. Complete histological necrosis was found in 38% of patients who underwent liver transplantation. One, 2 and 3-year survival rates were 95, 76 and 72%, respectively in patients who underwent primary/adjuvant therapy and 82, 68 and 51%, respectively in patients who underwent palliative therapy. Major complications (hemoperitoneum, pleuritis, pneumothorax and sepsis) were observed in 6.3% of the patients. Notably, rapid neoplastic progression was observed in two patients within 2 months after a single RFA session (neoplastic portal thrombosis and plurifocal HCC in one patient and cutaneous seeding and lung metastases in another patient). Majority of the HCC patients treated by percutaneous RFA can achieve local control of the tumor in HCCs less than or equal to 3 cm. As the procedure can be associated with major complications and cases of rapid neoplastic dissemination may occur, a more accurate selection of candidates to RFA treatment is advisable.

  14. Time-related prevalence of postoperative atrial fibrillation after stand-alone minimally invasive radiofrequency ablation.

    Science.gov (United States)

    La Meir, Mark; Gelsomino, Sandro; Luca, Fabiana; Pison, Laurent; Chambille, Pol; Parise, Orlando; Crijns, Harry J; Maessen, Jos G

    2011-07-01

    We present our results with minimally invasive surgical treatment of lone atrial fibrillation (LAF) employing a radiofrequency (RF) source through a bilateral thoracoscopy. Between January 2007 and January 2011, 28 consecutive patients (85.7% male, mean age 67.1 ± 9.1 years) with LAF underwent video-assisted bilateral RF ablation. Fourteen patients (50%) had paroxysmal, five (17.8%) persistent, and nine (32.2%) long-persistent LAF. All patients were followed-up according to the Heart Rhythm Society/ European Heart Rhythm Association/European Cardiac Arrhythmia Society (HRS/EHRA/ECA) and success/failure was reported as suggested by Society of Thoracic Surgeon (STS) guidelines. Mean follow-up was 27.8 ± 8.6 months. Time-related prevalence of postoperative AF was 4.5% at 36 months. Success was much more likely in subjects with paroxysmal (3-year prevalence, 0%) or persistent (3-year prevalence, 0%) than long-standing persistent LAF (3-year prevalence, 8.3%). At 36 months the estimated prevalence of antiarrhythmic drugs was 11.3% (8.8 to 13.7). No major thromboembolic events were detected during the follow-up period and 36-month prevalence of Warfarin use was 15.2% (11.5 to 18.1). Finally, no patient underwent electrical cardioversion. This approach yielded satisfactory results with a high degree of safety. Further larger studies are necessary to confirm our findings.  © 2011 Wiley Periodicals, Inc.

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

    Science.gov (United States)

    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.

  16. Early diffuse recurrence of hepatocellular carcinoma after percutaneous radiofrequency ablation: analysis of risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hee Young; Rhim, Hyunchul; Lee, Min Woo; Kim, Young-sun; Choi, Dongil; Park, Min Jung; Kim, Young Kon; Kim, Seong Hyun; Lim, Hyo Keun [Samsung Medical Center, Sungkyunwan University, School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of)

    2013-01-15

    To evaluate the risk factors affecting early diffuse recurrence within 1 year of percutaneous ultrasound-guided radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Out of 146 patients who received transcatheter arterial chemoembolisation (TACE) for treatment of recurrent HCC after percutaneous ultrasound-guided RFA, we selected 23 patients with early diffuse recurrence. Early diffuse recurrence was defined as three or more new recurrent HCCs within 1 year of initial RFA. As a control group, we selected 23 patients, matched exactly for age and sex, in which there was no local tumour progression or new recurrence after RFA. To analyse the risk factors, we examined patient factors and tumour factors. Recurrent tumours occurred from 30 to 365 days after RFA (median time, 203 days). Univariate analysis indicated that larger tumour size and poorly defined margin were significant risk factors (P < 0.05). Multivariate analysis indicated that poorly defined margin was a significant risk factor (P < 0.05). Larger tumour size and poorly defined margin may be risk factors for early diffuse recurrence of HCC within 1 year of RFA. Tumours with such risk factors should be treated with a combination of TACE to minimise the potential for therapeutic failure. (orig.)

  17. Efficacy of computed tomography guided radiofrequency ablation forosteoid osteomas in 31 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hoon; Ahn, Joong Mo; Lee, Joon Woo; Lee, Guen Young; Lee, Eu Gene; Oh, Joo Han; Cho, Hwan Seong; Kang, Heung Sik [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2015-04-15

    To present the clinical outcome of computed tomography (CT) guided radiofrequency ablation (RFA) for osteoid osteoma. Thirty-one patients (M:F = 23:8, mean age: 20 years, range: 4-54 years) who underwent RFA for clinically suspected osteoid osteoma from May 2004 to December 2013 were retrospectively reviewed. RFA was done in all cases under CT guidance by one of three radiologists in our department. Electronic medical records and images were retrospectively reviewed in all patients. Lesions were located in femur (n = 20), tibia (n = 5), fibula (n = 2), humerus (n = 3), talus (n = 2), and calcaneus (n = 1). On discharge, 27 of 33 cases showed complete remission of pain (82%). One major complication (compartment syndrome) and 2 minor complications (reactive synovitis, minimal skin burn at electrode insertion site) were observed. On the last follow-up (0-78 months, mean: 12.6 months) 27 of 33 cases were successfully treated (82%) and had no more complaints. 3 cases presented remaining pain (9%). In 3 cases relapse occurred (9%) and RFA was repeated in 1 case. The repeated treatment was successful. CT-guided RFA is an effective method for the treatment of osteoid osteoma.

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

    Science.gov (United States)

    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.

  19. Analysis by MRI of residual tumor after radiofrequency ablation for early stage breast cancer.

    Science.gov (United States)

    Vilar, Vanessa Sales; Goldman, Suzan Menasce; Ricci, Marcos Desidério; Pincerato, Katia; Oliveira, Helio; Abud, Thiago Giansante; Ajzen, Sergio; Baracat, Edmund Chada; Szejnfeld, Jacob

    2012-03-01

    The objective of our study was to evaluate the effectiveness of MRI in the detection of possible residual lesions after radiofrequency ablation (RFA) in the treatment of breast cancer. We prospectively evaluated 14 patients who had undergone ultrasound-guided core biopsies diagnostic of invasive ductal carcinoma (IDC; range of diameters, 1.0-3.0 cm) and then ultrasound-guided percutaneous RFA with sentinel node biopsy as the primary treatment. Breast MRI was performed 1 week before RFA to evaluate tumor extension and again 3 weeks after RFA to verify the presence of possible residual lesions. Conventional surgical resection of the tumors was performed 1 week after RFA. The MRI findings were compared with histopathologic analyses to confirm the presence or absence of residual tumor. There was no residual enhancement in seven lesions on the postablation breast MRI scans. These findings were confirmed by negative histopathologic findings in the surgical specimens. The MRI scans of five patients showed small areas of irregular enhancement that corresponded to residual lesions. In the two remaining patients, we observed enhancement of almost the entire lesion, indicating that RFA had failed. Breast MRI is effective in detecting residual lesions after RFA in patients with IDC.

  20. High-amplitude pace mapping increases safety of radiofrequency catheter ablation of parahisian ectopic foci.

    Science.gov (United States)

    Mamchur, Sergey E; Kurilin, Mikhail Y

    2012-12-01

    The objective of the study is to assess the efficacy of high-amplitude pace mapping in terms of the atrioventricular (AV) block risk after radiofrequency catheter ablation (RCA) of parahisian ectopic foci. Twenty patients aged 38 ± 14 years with no structural heart disease underwent RCA of parahisian ectopic foci. All the patients were randomized into two groups: Group I (n = 11) had RCA performed in the region defined as ectopic focus by electrophysiology study and Group II (n = 9) had high-amplitude pacing performed in the region of "perfect" mapping. RCA was done only at the sites where high-amplitude pacing revealed the absence of His bundle capture. In group I, the efficacy of RCA was 54.5% and it was 100% in group II (P = 0.0195). Group II had no complications; in group I there were 27% of AV blocks (P = 0.0893). The late recurrence of ectopic activity was comparable in both groups: 3 (27%) and 2 (22%), respectively (P = 0.7953). In all the cases of recurrent ectopic activity and in all the cases of ineffective primary procedure, group I had effective reablation procedures performed using high-amplitude pace mapping. The overall efficacy in terms of repeated procedures was 90%. High-amplitude pace mapping increases primary and secondary efficacy of parahisian ectopic foci RCA and decreases the risk of AV block development. (PACE 2012;35:1458-1463). ©2012, The Authors. Research Institute for complex issues of Cardiovascular.

  1. Efficiency of radiofrequency ablation of pulmonary vein ostium for patients with atrial fibrillation and metabolics

    Directory of Open Access Journals (Sweden)

    E. L. Zaslavskaya

    2016-01-01

    Full Text Available The aim of this study is determination of predictors of efficiency of radiofrequency ablation (RFA in patients with atrial fibrillation (AF and metabolic syndrome (MS. Material and methods. 98 patients with AF (78 patients with AF and MS (IDF, 2005 and 20 patients without MS have been examined. Comparison groups included 50 patients with MS without arrhythmia and 50 practically healthy subjects. RFA was performed with Carto 3 navigation system. Follow-up period after RFA was 12 months. Epicardial fat thickness (EFT was measured with help of echo-cardiography. Results: patients with AF relapse had more MS components than those with effective procedure (3.21±1.18 and 1.73±1.14, accordingly, p<0.001. Initially, EFT of patients with AF relapse after RFA was larger that in patients without arrhythmia after exposure. EFT in patients with AF more than3.5 mmincreases probability of arrhythmia relapse in 1.87 times (OR: 1.87, 95 % CI 1.03 — 3.41, р = 0.04. Conclusion: determination of EFT with echo-cardiogaphy can be used in estimation of AF relapse risk after RFA.

  2. The Problems of Radiofrequency Ablation as an Approach for Advanced Unresectable Ductal Pancreatic Carcinoma

    Directory of Open Access Journals (Sweden)

    Raffaele Pezzilli

    2010-07-01

    Full Text Available Advanced ductal pancreatic carcinoma (PC remains a challenge for current surgical and medical approaches. It has recently been claimed that radiofrequency ablation (RFA may be beneficial for patients with locally advanced or metastatic PC. Using the MEDLINE database, we found seven studies involving 106 patients in which PC was treated using RFA. The PC was mainly located in the pancreatic head (66.9% with a median size of 4.6 cm. RFA was carried out in 85 patients (80.1% with locally advanced PC and in 21 (19.9% with metastatic disease. Palliative surgical procedures were carried out in 41.5% of the patients. The average temperature used was 90 °C (with a temperature range of 30–105 °C and the ratio between the number of passes of the probe and the size of the tumor in centimeters was 0.5 (range of 0.36–1. The median postoperative morbidity and mortality were 28.3% and 7.5%, respectively; the median survival was 6.5 months (range of 1–33 months. In conclusion, RFA is a feasible technique: however, its safety and long-term results are disappointing; Thus, the RFA procedure should not be recommended in clinical practice for a PC patient.

  3. PET-CT after radiofrequency ablation of colorectal liver metastases: Suggestions for timing and image interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Karin, E-mail: k.nielsen@vumc.nl [Department of Surgery, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Tilborg, Aukje A.J.M. van, E-mail: a.vantilborg@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Scheffer, Hester J., E-mail: hj.scheffer@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Meijerink, Martijn R., E-mail: mr.meijerink@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Lange-de Klerk, Elly S.M. de, E-mail: esm.delange@vumc.nl [Department of Epidemiology and Biostatistics, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Meijer, Sybren, E-mail: s.meijer@vumc.nl [Department of Surgery, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Comans, Emile F.I., E-mail: efi.comans@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands); Tol, M.Petrousjka van den, E-mail: mp.vandentol@vumc.nl [Department of Surgery, VU University Medical Centre, Boelelaan 1117, 1081 HV, Amsterdam (Netherlands)

    2013-12-01

    Introduction. The main area of concern regarding radiofrequency ablation (RFA) of colorectal liver metastases is the risk of developing a local site recurrence (LSR). Reported accuracy of PET-CT in detecting LSR is high compared to morphological imaging alone, but no internationally accepted criteria for image interpretation have been defined. Our aim was to assess criteria for FDG PET-CT image interpretation following RFA, and to define a timetable for follow-up detection of LSR. Methods. Patients who underwent RFA for colorectal liver metastases between 2005 and 2011, with FDG-PET follow-up within one year after treatment were included. Results of repeat FDG-PET scans were evaluated until a LSR was diagnosed. Results. One hundred-seventy scans were obtained for 79 patients (179 lesions), 57 scans (72%) were obtained within 6 months of treatment. Thirty patients developed local recurrence; 29 (97%) within 1 year. Only 2% of lesions of <1 cm and 4% of <2 cm showed a LSR. Conclusion. The majority of local site recurrences are diagnosed within one year after RFA. Regular follow-up using FDG PET-CT within this period is advised, so repeated treatment can be initiated. Rim-shaped uptake may be present until 4–6 months, complicating evaluation. The benefit in the follow-up of lesions <2 cm may be limited.

  4. Radiofrequency ablation to treat loco-regional recurrence of well-differentiated thyroid carcinoma.

    Science.gov (United States)

    Lee, Sun Jin; Jung, So Lyung; 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

    To evaluate the efficacy of radiofrequency ablation (RFA) in the treatment of loco-regional, recurrent, and well-differentiated thyroid carcinoma. 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. 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 loco-regional, recurrent, and well-differentiated thyroid carcinoma in patients at high surgical risk.

  5. Histological evaluation of drill fragments obtained during osteoid osteoma radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Akhlaghpoor, Shahram [Noor Medical Imaging Center, Tehran (Iran); Tehran University of Medical Sciences, Sina Hospital, Tehran (Iran); Aziz Ahari, Alireza; Ahmadi, Seyed Ali; Gohari Moghaddam, Katayoun [Tehran University of Medical Sciences, Sina Hospital, Tehran (Iran); Arjmand Shabestari, Abbas [Noor Medical Imaging Center, Tehran (Iran); Shahid Beheshti Medical University, Modrarres Hospital, Tehran (Iran); Alinaghizadeh, Mohammad Reza [Noor Medical Imaging Center, Tehran (Iran)

    2010-05-15

    Osteoid osteoma (OO) is a benign bone tumor diagnosed mainly on the basis of the patient's history and radiological data. Histological evaluation may not be available before treatment. The aim of this study was to assess the diagnostic value of a histological evaluation of the bone fragments obtained during radiofrequency ablation (RFA). During a 2-year period, 39 patients diagnosed clinically with OO were entered into this study. The procedure was performed under computed tomography (CT) guidance. An 11-gauge needle was initially placed as a coaxial guide. After drill removal, RFA was performed. Bone fragments collected from the drill were examined by two experienced pathologists, independently. There was strong association between pathologists' reports (P <0.001). In 27 cases (69.2%) this diagnosis was confirmed pathologically. No significant relationship was found between nidus diameter and positive histological findings (P = 0.35). Histological confirmation of OO based on drill fragments is similarly frequent as previously reported for standard bone biopsy. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Schalte, Gereon; Waning, Christian; Rossaint, Rolf; Mahnken, Andreas H. [University Hospital, RWTH Aachen, Aachen, (Germany); Henzler, Dietrich [Dalhousie University, Queen Elisabeth II Health Sciences Center, Halifax (Canada); Tacke, Josef [Interventional Radiology, Klinikum Passau, Passau (Germany)

    2010-12-15

    To investigate the effects of hepatic radiofrequency ablation (RFA) in patients with malignant liver disease with respect to inflammation activation and stress response. 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. TNF{alpha}, 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). 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 ({gamma} = 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. 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

  7. Mathematical and Ex Vivo Thermal Modeling for Renal Tumor Radiofrequency Ablation with Pyeloperfusion.

    Science.gov (United States)

    Glamore, Michael; Masterson, Thomas; Pease, Karli J; Lorber, Gideon; Nella, Kevin; Salas, Nelson; Leveillee, Raymond J

    2015-06-01

    Radiofrequency ablation (RFA) is an effective technique for the treatment of patients with small renal tumors, although it is often limited to tumors at least 2 cm from the renal pelvis or ureter. Retrograde pyeloperfusion (PPF) of the pelvis with cold saline during RFA may protect the pelvis and ureter. We designed a mathematical and ex vivo model of RFA to investigate the effects of PPF. Our theoretical model uses heat transfer principles simplifying the RFA probe to a heat-emitting cylinder within a material. In the ex vivo model, an RFA probe was placed 18 mm from the pelvis in porcine kidneys and with temperature probes on either side of the RFA probe. Control trials with no PPF were compared with either cold saline (2°C), warm saline (38°C), or antifreeze (-20°C) pumped into the renal calix at a rate of 60 mL/min. Ablated volumes were measured and confirmed histologically. The average steady state temperatures at each probe were highest with no PPF, followed by warm saline, cold saline, then antifreeze. Compared with no PPF, temperatures were significantly (Psaline (-8.4°C), cold saline (-18°C), and significantly colder at the calix (warm -14°C, cold -27°C). While RFA output a constant voltage, significantly lower resistances in warm (171Ω) and cold (124Ω) PPF vs no PPF (363Ω) translated to significantly greater power outputs in warm (40 W) and cold (42 W) vs no PPF (14 W). The ablated volumes were significantly higher in warm saline (2.3 cm(3)) vs cold saline (0.84 cm(3)) and no PPF (1.1 cm(3)). Mathematical modeling produced a predictive temperature curve with R2=0.44. PPF lowers temperatures throughout the entire kidney during RFA, most notably near the collecting system and is dependent on the temperature of the liquid used. In addition, PPF may cause less charring of the tissue around the probe resulting in lower resistance and higher power outputs.

  8. Evaluation of a tissue-mimicking thermochromic phantom for radiofrequency ablation.

    Science.gov (United States)

    Mikhail, Andrew S; Negussie, Ayele H; Graham, Cole; Mathew, Manoj; Wood, Bradford J; Partanen, Ari

    2016-07-01

    This work describes the characterization and evaluation of a tissue-mimicking thermochromic phantom (TMTCP) for direct visualization and quantitative determination of temperatures during radiofrequency ablation (RFA). TMTCP material was prepared using polyacrylamide gel and thermochromic ink that permanently changes color from white to magenta when heated. Color vs temperature calibration was generated in matlab by extracting RGB color values from digital photographs of phantom standards heated in a water bath at 25-75 °C. RGB and temperature values were plotted prior to curve fitting in mathematica using logistic functions of form f(t) = a + b/(1 + e((c(t-d)))), where a, b, c, and d are coefficients and t denotes temperature. To quantify temperatures based on TMTCP color, phantom samples were heated to temperatures blinded to the investigators, and two methods were evaluated: (1) visual comparison of sample color to the calibration series and (2) in silico analysis using the inverse of the logistic functions to convert sample photograph RGB values to absolute temperatures. For evaluation of TMTCP performance with RFA, temperatures in phantom samples and in a bovine liver were measured radially from an RF electrode during heating using fiber-optic temperature probes. Heating and cooling rates as well as the area under the temperature vs time curves were compared. Finally, temperature isotherms were generated computationally based on color change in bisected phantoms following RFA and compared to temperature probe measurements. TMTCP heating resulted in incremental, permanent color changes between 40 and 64 °C. Visual and computational temperature estimation methods were accurate to within 1.4 and 1.9 °C between 48 and 67 °C, respectively. Temperature estimates were most accurate between 52 and 62 °C, resulting in differences from actual temperatures of 0.6 and 1.6 °C for visual and computational methods, respectively. Temperature measurements

  9. Chronological changes of radiofrequency ablation zone in rabbit liver: an in vivo correlation between gross pathology and histopathology.

    Science.gov (United States)

    Song, Kyoung D; Lee, Min Woo; Rhim, Hyunchul; Kang, Tae Wook; Cha, Dong Ik; Yang, Jehoon

    2017-03-01

    To examine the gross pathology and histopathology of ablation zones created from radiofrequency (RF) ablation and to correlate their chronological changes. A total of 48 in vivo ablation zones (16 rabbit livers) were obtained immediately after and also 30 min, 1 h and 2 h after RF ablation and were subjected to haematoxylin and eosin (H&E) staining, nicotinamide adenine dinucleotide (NADH) diaphorase staining, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining. Chronological changes in gross pathology and histopathology were evaluated and correlated with each other. Peripheral red zones on gross pathology correlated with peripheral zones on H&E staining, lightly stained peripheral zones on NADH staining and peripheral positive zones on TUNEL staining. Central white zones on gross pathology correlated with combined central and border zones on H&E staining, central negative zones on NADH staining and combined central-positive and middle-negative zones on TUNEL staining. Boundary visibility between central white and peripheral red zones on gross pathology was significantly higher at 1 and 2 h than immediately after RF ablation. As time increased after RF ablation, visibility of the border zone on H&E staining and the grade of positively stained hepatocytes in the peripheral zone on TUNEL staining increased. Chronological changes in gross pathology of RF ablation zones correlated well with histopathology. The boundary between the central white and peripheral red zones tended to become clear at 1 h after RF ablation. Advances in knowledge: (1) RF ablation zones show chronological changes on gross pathology and histopathology. (2) Gross pathology and histopathology correlate well with each other.

  10. Effect of hiatal hernia size and columnar segment length on the success of radiofrequency ablation for Barrett's esophagus: a single-center, phase II clinical trial.

    Science.gov (United States)

    Korst, Robert J; Santana-Joseph, Sobeida; Rutledge, John R; Antler, Arthur; Bethala, Vivian; DeLillo, Anthony; Kutner, Donald; Lee, Benjamin E; Pazwash, Haleh; Pittman, Robert H; Rahmin, Michael; Rubinoff, Mitchell

    2011-11-01

    Hiatal hernia is common in patients with Barrett's esophagus. We sought to evaluate the effect of hiatal hernia size and initial columnar segment length on the success of radiofrequency ablation of Barrett's esophagus. A phase II clinical trial was conducted aimed at evaluating the success of radiofrequency ablation in eradicating Barrett's esophagus. Success was defined as complete replacement of the columnar lining with squamous mucosa and lack of intestinal metaplasia using light microscopy. Hiatal hernia size and columnar segment length were measured endoscopically. Sixty-seven patients were accrued to the protocol. In the 55 patients who completed radiofrequency ablation (43 successes, 12 failures), the mean hiatal hernia size was 3.3 cm (range, 0-10 cm), and the mean columnar segment length was 5.4 cm (range, 1-18 cm). The median length of the columnar segment was 3 cm in the successful cases and 8.5 cm in the failed cases (P = .002). Although the median hiatal hernia size was identical in the successful and failed cases (3 cm, P = .38), the median hiatal hernia size was 7 cm (P = .001) in the 6 patients who experienced nonhealing after the initial ablation. Patients who were successfully ablated but had larger hiatal hernias and longer columnar segment lengths required significantly more radiofrequency ablation sessions than those with smaller hernias and shorter segments (P = .003 and P = .007, respectively). Patients with larger hiatal hernias and longer columnar segments are more likely to experience failure or nonhealing after radiofrequency ablation. These patients also require more radiofrequency ablation treatments to achieve successful eradication of Barrett's esophagus. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  11. Combined use of radioiodine therapy and radiofrequency ablation in treating postsurgical thyroid remnant of differentiated thyroid carcinoma.

    Science.gov (United States)

    Long, Bin; Li, Linfa; Yao, Lifang; Chen, Shoucong; Yi, Heqing; Ye, Xuemei; Xu, Dong; Wu, Peng

    2015-11-01

    To determine whether postoperative radioiodine (RAI) combined with radiofrequency ablation (RFA) is an effective, safe, and feasible method for elimination of excessive postsurgical thyroid remnant for differentiated thyroid carcinoma (DTC). We took a prospective study and treated 12 DTC patients (4 males, 8 females, age 20-78 years) who underwent thyroidectomy for RFA followed by 131 I ablation. The pretreatment requires iodine-free diet and thyroid hormone withdrawal for 3-4 week. All the patients showed the level of serum thyroid-stimulating hormone (TSH) thyroid remnant in 99m Technetium (99m Tc) imaging. Serum TSH level was determined 1 day before RFA and on days 1, 7, 14 after RFA, and 99m Tc imaging was performed on day 14 after RFA. Subsequently, the patients were given an oral dosage of 3700 MBq 131 I for remnant ablation, and posttreatment whole body scan was performed on day 5 after ablation. Efficacy evaluation was done 4-6 months after treatment. The changes of variants before and after RFA were analyzed using Wilcoxon signed rank sum test. Serum TSH was thyroid remnant ablation was 91.7% (11/12), which was assessed 4-6 months after treatment. All patients reported neck discomfort and some are self-limiting, with no hoarseness, choking, or radiation thyroiditis symptoms. Five patients had puncture area pain, among which one patient had neck edema, which was relieved after prednisone treatment. Combined use of RAI therapy and radiofrequency ablation in treating excessive postsurgical thyroid remnant of DTC can be an effective approach and avoids re-operation. Long-term efficacy monitoring would further determine its feasibility.

  12. Quantitative magnetic resonance temperature mapping for real-time monitoring of radiofrequency ablation of the liver: an ex vivo study

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    Seror, Olivier [ERT CNRS/Universite Victor Segalen Bordeaux 2, Laboratoire d' Imagerie Moleculaire et Fonctionnelle, Bordeaux (France); Assistance Publique-Hopitaux de Paris/CHU Paris XIII, Service de Radiologie Hopital Jean Verdier, Bondy (France); Universite Paris 13, UPRES EA 3409, UFR SMBH, Bobigny (France); Lepetit-Coiffe, Matthieu; Quesson, Bruno; Moonen, Chrit T.W [ERT CNRS/Universite Victor Segalen Bordeaux 2, Laboratoire d' Imagerie Moleculaire et Fonctionnelle, Bordeaux (France); Trillaud, Herve [ERT CNRS/Universite Victor Segalen Bordeaux 2, Laboratoire d' Imagerie Moleculaire et Fonctionnelle, Bordeaux (France); Hopital Saint-Andre, CHU Bordeaux, Service de Radiologie, Bordeaux (France)

    2006-10-15

    We evaluated the feasibility and accuracy of real-time magnetic resonance (MR) thermometry for monitoring radiofrequency (RF) ablation in the liver. Continuous MR temperature mapping was used to monitor bipolar RF ablations performed in ex vivo livers with and without flow using two parallel electrodes. Macroscopic inspection of ablation zones was compared with thermal dose maps (TDm) and T1-weighted inversion recovery turbo spin echo (IR-TSE) images for their size and shape and the influence of flow. Pearson's correlation (r), Bland and Altman tests and kappa ({chi}K) tests were performed. The mean differences in ablation zone size between macroscopic and TDm and IR-TSE measurements were +4 mm and -2 mm, respectively. TDm was well correlated with macroscopy (r=0.77 versus r=0.44 for IR-TSE). TDm was found to be more precise for shape recognition ({chi}K=0.73 versus {chi}K=0.55 for IR-TSE) and for detection of an intact ring of liver due to the cooling effect of flow which was impossible with IR-TSE. Simultaneous monitoring of RF ablation by MR thermometry is feasible and reliable for predicting the shape of ablation zones and the impact of the heat-sink effect of flow. Further studies are needed to confirm these results in vivo. (orig.)

  13. Comparison of heat induced damage at the saphenofemoral junction after ablation with 1,470 nm laser or radiofrequency.

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    Ozcinar, Evren; Cakici, Mehmet; Korun, Oktay; Han, Unsal; Kiziltepe, Ugursay

    2017-03-01

    The aim of this study was to evaluate the heat induced damage at the saphenofemoral junction level according to histopathological changes after radiofrequency or 1,470 nm radial tip laser ablation. Varicose vein segments of 6-10 mm in diameter were exposed to radiofrequency (Closure Fast catheter, 7 cm heat segment, one cycle, 15 seconds, 10 Watt, 120 °C) or laser ablation (1,470 nm radial tip, continuous wave, vein diameter: 6 cm/8 cm/10 cm-power: 10 Watt-pullback speed: 2.2 mm/s, 1.7 mm/s, 1.3 mm/s-LEED: 45J/cm, 60J/cm, 75J/cm-EFE 25J/cm(2), respectively). Approximate 2 cm segments of the vein were left untreated, then histopathological examinations of the untouched segments (5 slices: level 1 - furthest segment, level 2 - nearest segment) for heat induced damage were performed. A total damage scoring system was established, including the presence of endothelial swelling, intimal thickening, cellular vacuolisation in the muscle layer, oedema in the tunica media, and extent of necrosis. At level 1, the furthest segment of the specimen, there was no significant difference between the laser and control group, while the total damage score of the radiofrequency group was significantly higher than the control group (p laser group at level 1 (p ablation seems to cause more histological damage than laser ablation in this ex vivo study. Further in vivo studies are necessary, in order to validate these findings.

  14. Analysis of the effect of renal excretory system cooling during thermal radiofrequency ablation in an animal model

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    Andre Meireles

    2014-01-01

    Full Text Available Objective: Analysis of renal excretory system integrity and efficacy of radiofrequency ablation with and without irrigation with saline at 2 o C (SF2. Materials and Methods: The median third of sixteen kidneys were submitted to radiofrequency (exposition of 1 cm controlled by intra-surgical ultrasound, with eight minutes cycles and median temperature of 90 o C in eight female pigs. One excretory renal system was cooled with SF2, at a 30ml/min rate, and the other kidney was not. After 14 days of post-operatory, the biggest diameters of the lesions and the radiological aspects of the excretory system were compared by bilateral ascending pyelogram and the animals were sacrificed in order to perform histological analysis. Results: There were no significant differences between the diameters of the kidney lesions whether or not exposed to cooling of the excretory system. Median diameter of the cooled kidneys and not cooled kidneys were respectively (in mm: anteroposterior: 11.46 vs. 12.5 (p = 0.23; longitudinal: 17.94 vs. 18.84 (p = 0.62; depth: 11.38 vs. 12.25 (p = 0.47. There was no lesion of the excretory system or signs of leakage of contrast media or hydronephrosis at ascending pyelogram. Conclusion: Cooling of excretory system during radiofrequency ablation does not significantly alter generated coagulation necrosis or affect the integrity of the excretory system in the studied model.

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

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    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.

  16. [The application of Atricure bipolar radiofrequency system in ablation of different parts and different times of pig heart atrium and the analysis of transmural lesions].

    Science.gov (United States)

    Liu, Pei-sheng; Chen, Xin; Liu, Ming

    2010-12-15

    To analyze the transmural lesions of different parts of the pig heart atrium received different times of ablation applied with Atricure bipolar radiofrequency system. Six fresh (ex vivo timepig hearts with atrium preserved intact were used as the experimental objects and experimental groups were divided according to the ablation position. The Atricure bipolar radiofrequency system was applied in the ablation of the parts of the atrium, such as posterior wall of left atrium, anterior wall of left atrium, anterior wall of right atrium and posterior wall of left atrium close to mitral posterior ring. Ablate the position of the atrium lengthened about 2.0 cm with the same thickness with an interval of 0.5 cm for 4 times respectively, also recording the time of every ablation. For each part and each time of ablation, the ablated atrial tissue was preserved with 4% formaldehyde and 5% glutaraldehyde, and was sent for observation under light microscope and transmission electron microscope. The ablation time and lesion were analyzed statistically. In the same position of the atrium, ablation time decreased with the times of the ablation, in different position of the atrium with same time of ablation, time showed a positive proportion with the thickness of the atrium. Atricure bipolar radiofrequency system is very safe and efficient, also convenient for manipulation. With regard to the relatively thinner part of the atrium, such as posterior wall and anterior wall of left atrium, at least two times of ablation can ensure transmural lesion of the atrial tissue, but to the position of the atrium such as anterior wall of right atrium and posterior wall of left atrium close to mitral posterior ring, 3 to 4 times of ablation can ensure transmural lesion of the atrial tissue.

  17. Pathomorphologic evaluation of pulmonary radiofrequency ablation: proof of cell death is characterized by DNA fragmentation and apoptotic bodies.

    Science.gov (United States)

    Clasen, Stephan; Krober, Stefan-Martin; Kosan, Bora; Aebert, Hermann; Fend, Falko; Bomches, Andrea; Claussen, Claus D; Pereira, Philippe L

    2008-12-01

    Radiofrequency (RF) ablation is an increasingly applied technique. Promising results of hepatic RF ablation raised expectations of its capabilities for treatment of primary and secondary lung tumors. Because of different thermal and electrical properties of lung tissue, compared with liver tissue, a simple analogy of tissue response is not possible. The authors aimed to evaluate the effectiveness of image-guided pulmonary RF ablation and to characterize pathomorphology of tissue response. RF ablations of 11 pulmonary malignancies in 9 patients were performed under computed tomography (CT)-guidance. Three days after RF ablation, surgical resection was performed followed by pathologic examination. Specimens were evaluated macroscopically, histologically by hematoxylin and eosin (H & E) staining, terminal deoxy-nucleotidyl transferase-mediated nick end-labeling (TUNEL), and electron microscopy. Tumor tissues and adjacent lung tissues were characterized by double-strand fragmentation as determined by TUNEL. Ultrastructurally apoptotic bodies were found, indicating apoptotic cells. Criteria for tissue necrosis were not fulfilled by standard histological staining (H & E), showing preserved tissue architecture and only few microscopic cellular details suggestive of tumor regression. Because of DNA fragmentation, as determined by TUNEL and results from electron microscopy, the authors confirmed the tumor tissue to be completely ablated in 10 (90.9%) cases. However, in 2 cases, a safety margin was absent. CT-guided pulmonary RF ablation of pulmonary malignancies is a locally effective treatment. Three days after RF ablation, tumor tissue seemed to be thermally fixed still showing characteristics of vital tumor tissue in standard histological staining; however the tissue proved to be in regression toward coagulative necrosis verified ultrastructurally and by TUNEL. (c) 2008 American Cancer Society

  18. Intermediate outcomes and predictors of efficacy in the radiofrequency ablation of 100 pathologically proven renal cell carcinomas.

    Science.gov (United States)

    McClure, Timothy D; Chow, Daniel S; Tan, Nelly; Sayre, James A; Pantuck, Allan J; Raman, Steven S

    2014-11-01

    To determine oncologic outcomes and predictors of primary efficacy, including RENAL nephrometry scores (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines), after percutaneous radiofrequency (RF) ablation of proven renal cell carcinoma (RCC). Patients who underwent percutaneous computed tomography- and ultrasound-guided RF ablation for histologically proven RCC from 2004 to 2011 were evaluated. Clinical data, pathologic findings, technical details, and outcomes were reviewed. Univariate and multivariate logistic regression analysis was performed to determine predictors of primary technique effectiveness and complications. Local tumor progression-free, metastasis-free, and overall survival were calculated. One hundred RCC lesions underwent 115 RF ablation sessions in 84 patients. Median follow-up was 24 months (mean, 27 mo; range, 1-106 mo). Efficacy of RF ablation was defined per International Working Group of Image-Guided Tumor Ablation criteria. Total, primary, and secondary technique effectiveness rates were 95% (95 of 100), 86% (86 of 100), and 9% (nine of 100), respectively. Primary efficacy was associated with size (P < .001), proximity to collecting system (P = .001), RENAL nephrometry score (P < .001), and number of ablation zones (P < .001). Complications occurred in 13% of patients, without procedure-related deaths. The median 2.1-year local progression-free, metastasis-free, disease-specific, and overall survival rates were 86%, 98.7%, 100%, and 97.6%, respectively. Percutaneous image-guided RF ablation for RCC provides excellent intermediate oncologic control. Location, size, proximity to the collecting system, low RENAL nephrometry score, and number of ablation zones predict primary efficacy. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  19. Endovascular radiofrequency ablation for varicose veins: an evidence-based analysis.

    Science.gov (United States)

    2011-01-01

    The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and cost-effectiveness of endovascular radiofrequency ablation (RFA) for the treatment of primary symptomatic varicose veins. The Ontario Health Technology Advisory Committee (OHTAC) met on August 26th, 2010 to review the safety, effectiveness, durability, and cost-effectiveness of RFA for the treatment of primary symptomatic varicose veins based on an evidence-based review by the Medical Advisory Secretariat (MAS). CLINICAL CONDITION: Varicose veins (VV) are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins). SYMPTOMS TYPICALLY AFFECT THE LOWER EXTREMITIES AND INCLUDE (BUT ARE NOT LIMITED TO): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad or worse as other chronic diseases such

  20. Multipolar radiofrequency ablation with internally cooled electrodes: experimental study in ex vivo bovine liver with mathematic modeling.

    Science.gov (United States)

    Clasen, Stephan; Schmidt, Diethard; Boss, Andreas; Dietz, Klaus; Kröber, Stefan M; Claussen, Claus D; Pereira, Philippe L

    2006-03-01

    To evaluate the size and geometry of thermally induced coagulation by using multipolar radiofrequency (RF) ablation and to determine a mathematic model to predict coagulation volume. Multipolar RF ablations (n = 80) were performed in ex vivo bovine livers by using three internally cooled bipolar applicators with two electrodes on the same shaft. Applicators were placed in a triangular array (spacing, 2-5 cm) and were activated in multipolar mode (power output, 75-225 W). The size and geometry of the coagulation zone, together with ablation time, were assessed. Mathematic functions were fitted, and the goodness of fit was assessed by using r(2). Coagulation volume, short-axis diameter, and ablation time were dependent on power output and applicator distance. The maximum zone of coagulation (volume, 324 cm(3); short-axis diameter, 8.4 cm; ablation time, 193 min) was induced with a power output of 75 W at an applicator distance of 5 cm. Coagulation volume and ablation time decreased as power output increased. Power outputs of 100-125 W at applicator distances of 2-4 cm led to a reasonable compromise between coagulation volume and ablation time. At 2 cm (100 W), coagulation volume, short-axis diameter, and ablation time were 66 cm(3), 4.5 cm, and 19 min, respectively; at 3 cm (100 W), 90 cm(3), 5.2 cm, and 22 min, respectively; at 4 cm (100 W), 132 cm(3), 6.1 cm, and 27 min, respectively; at 2 cm (125 W), 56 cm(3), 4.2 cm, and 9 min, respectively; at 3 cm (125 W), 73 cm(3), 4.9 cm, and 12 min, respectively; and at 4 cm (125 W), 103 cm(3), 5.5 cm, and 16 min, respectively. At applicator distances of 4 cm (>125 W) and 5 cm (>100 W), the zones of coagulation were not confluent. Coagulation volume (r(2) = 0.80) and RF ablation time (r(2) = 0.93) were determined by using the mathematic model. Multipolar RF ablation with three bipolar applicators may produce large volumes of confluent coagulation ex vivo. A compromise is necessary between prolonged RF ablations at lower

  1. The quest for durable lesions in catheter ablation of atrial fibrillation - technological advances in radiofrequency catheters and balloon devices.

    Science.gov (United States)

    Maurer, Tilman; Kuck, Karl-Heinz

    2017-08-01

    Atrial fibrillation is the most common cardiac arrhythmia and represents a growing clinical, social and economic challenge. Catheter ablation for symptomatic atrial fibrillation has evolved from an experimental procedure into a widespread therapy and offers a safe and effective treatment option. A prerequisite for durable PVI are transmural and contiguous circumferential lesions around the pulmonary veins. However, electrical reconnection of initially isolated pulmonary veins remains a primary concern and is a dominant factor for arrhythmia recurrence during long-term follow up. Areas covered: This article discusses the physiology of lesion formation using radiofrequency-, cryo- or laser- energy for pulmonary vein isolation and provides a detailed review of recent technological advancements in the field of radiofrequency catheters and balloon devices. Finally, future directions and upcoming developments for the interventional treatment of atrial fibrillation are discussed. Expert commentary: Durable conduction block across deployed myocardial lesions is mandatory not only for PVI but for any other cardiac ablation strategy as well. A major improvement urgently expected is the intraprocedural real-time distinction of durable lesions from interposed gaps with only transiently impaired electrical conduction. Furthermore, a simplification of ablation tools used for PVI is required to reduce the high technical complexity of the procedure.

  2. HRV changes before and after radiofrequency ablation in patients with different origin of right ventricular outflow tract ventricular premature contraction

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    Yi-Ming Ma

    2017-04-01

    Full Text Available Objective: To observe the HRV changes before and after the radiofrequency current catheter ablationventricular premature beats originated from different site of right ventricular outflow tract. Methods: A total of 102 patients with frequent RVOT-VPC admitted to our hospital were accepted radiofrequency current catheter ablation (RF. According to the origin of RVOT-VPC, it was divided into 2 groups, one is from ventricular septum, and the other one is from free wall, and in each group, male and female are observed separately. Results: (1 HRV before RF ablation: 1 rMSSD in the female patients with RVOT-VPC from free wall was significantly lower than those from septum; 2 frequency domain index (W, LF were higher than normal range, and in male patients, LF/HF1. (2 HRV after RF ablation: 1 Significant changes were found in female patients with RVOT-VPC from septum, rMSSD, PNN50, HF and LF decreased; 2 In female patients with RVOT-VPC from free wall, rMSSD decreased; 3 In male patients, there were no significant HRV changes found before and after RF ablation. (3 Heart rate changes: 1 In female patients with RVOT-VPC from septum, heart rate decreased significantly [(76.47±9.47 bpm vs (69.29±14.59 bpm]. 2 No significant changes were found in male patients. Conclusion: In patients with RVOT-PVC sympathetic and vagus excitability increased, and after catheter ablation, in female patients with RVOT-PVC originated from septum, the HRV index relating to sympathetic and vagus excitability significantly decreased.

  3. Percutaneous dual-switching monopolar radiofrequency ablation using a separable clustered electrode: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Tae Won; Lee, Jeong Min; Lee, Dong Ho; Lee, Jeong Hoon; Yu, Su Jong; Kim, Yoon Jun; Yoon, Jung Hwan; Han, Joon Koo [Seoul National University Hospital, Seoul (Korea, Republic of)

    2017-09-15

    To prospectively evaluate the safety and therapeutic effectiveness of dual-switching monopolar (DSM) radiofrequency ablation (RFA) for the treatment of hepatocellular carcinoma (HCC), and to retrospectively compare the results with those of single-switching monopolar (SSM) RFA in a historical control group. This study was approved by the Institutional Review Board, with informed consent obtained from all patients. Fifty-two HCC patients who underwent DSM-RFA using a separable clustered electrode and dual-generators were prospectively enrolled. Technical parameters, complications, technical success, technical effectiveness, and local tumor progression (LTP) rates were evaluated by means of post-procedural and follow-up imaging. Thereafter, the outcome of DSM-RFA was compared with those of 249 retrospectively included HCC patients treated with SSM-RFA.There were two major complications (3.8%, 2/52) including pleural and pericardial effusion in the DSM-RFA group. The DSM-RFA yielded a 100% technical success rate, a 98.1% technical effectiveness rate, and a 4.3% 2-year LTP rate. In a retrospective comparison between the two groups, DSM-RFA created significantly larger ablation volume (4.20 ± 2.07 cm{sup 3}/min vs. 3.03 ± 1.99 cm{sup 3}/min, p < 0.01), and delivered higher energy (1.43 ± 0.37 kcal/min vs. 1.25 ± 0.50 kcal/min, p < 0.01) per given time, than SSM-RFA. There was no significant difference in major procedure-related complications (3.8% vs. 4.4%) and technical effectiveness rate (98.1% vs. 96.4%) between the two groups (p = 1.00). In addition, the 2-year LTP rate of DSM-RFA and SSM-RFA were 4.3% and 10.1%, respectively (p = 0.15). DSM-RFA using a separable clustered electrode is safe and provides high local tumor control and good preliminary clinical outcome for small HCCs, which are at least comparable to those of SSM-RFA.

  4. 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

    Directory of Open Access Journals (Sweden)

    Bischoff-Everding C

    2016-01-01

    Full Text Available Christoph Bischoff-Everding,1 Ruediger Soeder,2 Benno Neukirch3 1HGC GesundheitsConsult GmbH, Duesseldorf, Germany; 2Gynecological Joint Practice, Mainz, Germany; 3Faculty of Health Care, Hochschule Niederrhein – University of Applied Sciences, Krefeld, Germany 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

  5. Fiber-Optic Temperature and Pressure Sensors Applied to Radiofrequency Thermal Ablation in Liver Phantom: Methodology and Experimental Measurements

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    Daniele Tosi

    2015-01-01

    Full Text Available Radiofrequency thermal ablation (RFA is a procedure aimed at interventional cancer care and is applied to the treatment of small- and midsize tumors in lung, kidney, liver, and other tissues. RFA generates a selective high-temperature field in the tissue; temperature values and their persistency are directly related to the mortality rate of tumor cells. Temperature measurement in up to 3–5 points, using electrical thermocouples, belongs to the present clinical practice of RFA and is the foundation of a physical model of the ablation process. Fiber-optic sensors allow extending the detection of biophysical parameters to a vast plurality of sensing points, using miniature and noninvasive technologies that do not alter the RFA pattern. This work addresses the methodology for optical measurement of temperature distribution and pressure using four different fiber-optic technologies: fiber Bragg gratings (FBGs, linearly chirped FBGs (LCFBGs, Rayleigh scattering-based distributed temperature system (DTS, and extrinsic Fabry-Perot interferometry (EFPI. For each instrument, methodology for ex vivo sensing, as well as experimental results, is reported, leading to the application of fiber-optic technologies in vivo. The possibility of using a fiber-optic sensor network, in conjunction with a suitable ablation device, can enable smart ablation procedure whereas ablation parameters are dynamically changed.

  6. Efficacy of multi-electrode duty-cycled radiofrequency ablation in patients with paroxysmal and persistent atrial fibrillation.

    Science.gov (United States)

    Koźluk, Edward; Balsam, Paweł; Peller, Michał; Kiliszek, Marek; Lodziński, Piotr; Piątkowska, Agnieszka; Małkowska, Sylwia; Rodkiewicz, Dariusz; Kochanowski, Janusz; Opolski, Grzegorz

    2013-01-01

    Radiofrequency (RF) catheter ablation is a first-line therapy for patients withdrug-refractory atrial fibrillation (AF). Complete isolation of electrical potentials at the ostium of pulmonary vein (PV) is a challenging procedure. There are different techniques and devicesused for PV isolation (PVI). The objective of this study was to evaluate the efficacy and safety of PV ablation catheter (PVAC). A total of 67 consecutive patients with paroxysmal and persistent AF were treated with the PVAC. The patients' information were obtained from clinical charts. Follow-up was obtained by one day Holter monitoring at 2, 4, 6, 8, 10 and 12 months after ablation and ECG registration if any symptoms or arrhythmia occurred. The median follow-up duration was 16 months (IQR: 12-20 months). In the population which was available at follow-up (n = 60), 22 (36.7%) patients were in sustained sinus rhythm (SR) without anti-arrhythmic drugs (AAD). Overall 26 (43.3%) patients were in sustained SR with and without AAD. In the paroxysmal AF group, after a single PVAC ablation procedure (n = 39), 19 (48.7%) patients had sustained SR without AAD. In the persistent AF group (n = 15), after the single PVAC ablation, 2 (13.3%) patients had sustained SR without AAD. PVI with PVAC is a safe procedure with 48.7% efficacy in patients with paroxysmal AF. The efficacy of PVAC in patients with persistent or long-standing persistent AF is not acceptable.

  7. Intraprocedural contrast-enhanced ultrasound (CEUS) in liver percutaneous radiofrequency ablation: clinical impact and health technology assessment.

    Science.gov (United States)

    Mauri, Giovanni; Porazzi, Emanuele; Cova, Luca; Restelli, Umberto; Tondolo, Tania; Bonfanti, Marzia; Cerri, Anna; Ierace, Tiziana; Croce, Davide; Solbiati, Luigi

    2014-04-01

    To assess the clinical and the economic impacts of intraprocedural use of contrast-enhanced ultrasound (CEUS) in patients undergoing percutaneous radiofrequency ablation for small (impact, cost effectiveness, and budget, organisational and equity impacts were evaluated and compared with standard treatment without intraprocedural CEUS using the health technology assessment approach. Intraprocedural CEUS detected incomplete ablation in 34/93 (36.5 %) patients, who underwent additional treatment during the same session. At 24-h, complete ablation was found in 88/93 (94.6 %) patients. Thus, a second session of treatment was spared in 29/93 (31.1 %) patients. Cost-effectiveness analysis revealed an advantage for the use of intraprocedural CEUS in comparison with standard treatment (4,639 vs 6,592) with a 21.9 % reduction of the costs to treat the whole sample. Cost per patient for complete treatment was  4,609 versus  5,872 respectively. The introduction of intraprocedural CEUS resulted in a low organisational impact, and in a positive impact on equity Intraprocedural use of CEUS has a relevant clinical impact, reducing the number of re-treatments and the related costs per patient. • CEUS allows to immediately asses the result of ablation. • Intraprocedural CEUS decreases the number of second ablative sessions. • Intraprocedural CEUS may reduce cost per patient for complete treatment. • Use of intraprocedural CEUS may reduce hospital budget. • Its introduction has low organisational impact, and relevant impact on equity.

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

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    Ho-Su Kim

    2013-09-01

    Full Text Available 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.

  9. Computed tomography-guided transpulmonary radiofrequency ablation for hepatocellular carcinoma located in hepatic dome.

    Science.gov (United States)

    Toyoda, Mitsuo; Kakizaki, Satoru; Horiuchi, Katsuhiko; Katakai, Kenji; Sohara, Naondo; Sato, Ken; Takagi, Hitoshi; Mori, Masatomo; Nakajima, Takahito

    2006-01-28

    To determine the feasibility of performing computed tomography (CT)-guided transpulmonary radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) located in the hepatic dome. A total of seven patients with HCC comprising seven nodules located in the hepatic dome were treated from April 2004 to December 2004. CT-guided transpulmonary RFA was performed using a cool-tip type electrode (Radionics Company) based on a standardized energy protocol. All tumors located in the hepatic dome were not detectable by the usual ultrasound (US) methods. The lesion diameters ranged from 15 to 27 mm. RFA was technically feasible in all the patients. The puncture procedure was performed twice or less and the total average performance time was 40.6 min. Local tumor control was achieved in all the patients. The necrosis diameter ranged from 25 to 35 mm. The mean follow-up period was 9.6 (7-14 mo) mo. There was no local recurrence at the follow-up points. Pneumothorax requiring pleural drainage was the main complication, which was observed in two of the seven patients (28.6%). However, it improved with chest drainage tube, and the tube could be removed within 2-3 d. No other major complications were observed. CT-guided puncture is useful for the treatment of tumors located in the hepatic dome which are hardly detectable by US, even though pneumothorax sometimes may occur as a complication. In the cases with adhesion in the pleura for which artificial pleural effusion methods are not appropriate, CT-guided RFA is thus considered to be an alternative treatment for HCC located in the hepatic dome.

  10. Quality of Life Following Radiofrequency Ablation of Dysplastic Barrett’s Esophagus

    Science.gov (United States)

    Shaheen, Nicholas J.; Peery, Anne F.; Hawes, Robert H.; Rothstein, Richard I.; Spechler, Stuart J.; Galanko, Joseph A.; Campbell, Marci; Carr, Carol; Fowler, Beth; Walsh, Joan; Siddiqui, Ali A; Infantolino, Anthony; Wolfsen, Herbert C.

    2011-01-01

    Background and study aims The impact of the diagnosis and treatment of dysplastic Barrett’s esophagus (BE) on quality of life (QoL) is poorly understood. This study assessed the influence of dysplastic BE on QoL and evaluated if endoscopic treatment of dysplastic BE with radiofrequency ablation (RFA) improves QoL. Patients and methods We analyzed changes in QoL in the AIM Dysplasia Trial—a multicenter study of patients with dysplastic BE randomized to RFA therapy or a sham intervention. We developed a 10-item questionnaire to assess the influence of dysplastic BE on QoL. The questionnaire was completed by subjects at baseline and 12 months. Results One hundred and twenty-seven patients were randomized to RFA (n=84) or sham (n=43). At baseline, the majority of subjects reported esophageal cancer worry (71% RFA, 85% sham) and esophagectomy worry (61% RFA, 68% sham). Subjects reported depression, impaired QoL, worry, stress and dissatisfaction with the condition of their esophagus. Of those randomized, 117 subjects completed the 12 month endpoint. Compared to sham, subjects treated with RFA had significantly reduced esophageal cancer worry (p=0.003) and esophagectomy worry (p=0.009). They also had significantly reduced depression (p=0.02), general worry with the condition of their esophagus (p≤0.001), impact on daily QoL (p=0.009), stress (p=0.03), dissatisfaction with the condition of their esophagus (p≤0.001) and impact on work and family life (p=0.02). Conclusions Inclusion in the treatment group of this randomized, sham-controlled trial of RFA was associated with improvement in disease-specific health-related quality of life. This improvement appears secondary to a perceived decrease in the risk of cancer. PMID:20886398

  11. Frequency of and predictive factors for vascular invasion after radiofrequency ablation for hepatocellular carcinoma.

    Science.gov (United States)

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

    2014-01-01

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

  12. An efficient cardiac mapping strategy for radiofrequency catheter ablation with active learning.

    Science.gov (United States)

    Feng, Yingjing; Guo, Ziyan; Dong, Ziyang; Zhou, Xiao-Yun; Kwok, Ka-Wai; Ernst, Sabine; Lee, Su-Lin

    2017-07-01

    A major challenge in radiofrequency catheter ablation procedures is the voltage and activation mapping of the endocardium, given a limited mapping time. By learning from expert interventional electrophysiologists (operators), while also making use of an active-learning framework, guidance on performing cardiac voltage mapping can be provided to novice operators or even directly to catheter robots. A learning from demonstration (LfD) framework, based upon previous cardiac mapping procedures performed by an expert operator, in conjunction with Gaussian process (GP) model-based active learning, was developed to efficiently perform voltage mapping over right ventricles (RV). The GP model was used to output the next best mapping point, while getting updated towards the underlying voltage data pattern as more mapping points are taken. A regularized particle filter was used to keep track of the kernel hyperparameter used by GP. The travel cost of the catheter tip was incorporated to produce time-efficient mapping sequences. The proposed strategy was validated on a simulated 2D grid mapping task, with leave-one-out experiments on 25 retrospective datasets, in an RV phantom using the Stereotaxis Niobe ® remote magnetic navigation system, and on a tele-operated catheter robot. In comparison with an existing geometry-based method, regression error was reduced and was minimized at a faster rate over retrospective procedure data. A new method of catheter mapping guidance has been proposed based on LfD and active learning. The proposed method provides real-time guidance for the procedure, as well as a live evaluation of mapping sufficiency.

  13. The procedure outcome of laparoscopic resection for 'small' hepatocellular carcinoma is comparable to vlaparoscopic radiofrequency ablation.

    Science.gov (United States)

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

    2015-01-01

    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). 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. 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. 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.

  14. Radiofrequency Ablation for the Treatment of Lung Neoplasms: 
A Retrospective Study of 329 Cases

    Directory of Open Access Journals (Sweden)

    Qiang LU

    2011-11-01

    Full Text Available Background and objective In recent years, radiofrequency ablation (RFA has been increasingly utilized as a non-surgical treatment option for patients with primary and metastatic lung tumors. The aim of this study is to evaluate the safety and therapeutic effects of RFA among patients with pulmonary neoplasms. Methods Patients with lung tumors treated with RFA from October 1999 to July 2006 in this hospital were enrolled into the study. A total of 329 cases, 237 primary lung tumors and 92 metastatic tumors, were retrospectively analyzed and evaluated for complications, local progression, and overall survival after one, two, and five years after RFA. Results The complications of RFA with surgery included 63 (19.1% patients with pneumothorax, 14 (4.2% with hemoptysis (one death, 10 (3.0% with hemothorax, 15 (4.5% with pneumonia, and three (0.9% with pericardial tamponade (one death. The mortality within 30 days was 0.6%. Needle tract tumors were observed in 6 patients (1.8%. The median time for progression was 21.6 months. The overall survival rates at one, two, and five years after RFA were 68.2%, 35.3% and 20.1%, respectively. Up to 78 (23.7% patients with tumors that exceed 4 cm developed local progression, and a significant difference was found. No significant difference was found among patients with tumors less than 3 cm and among those with 3 cm-4 cm tumors. Conclusion RFA is a well-tolerated, reliable, and safe method for the treatment of lung malignancies.

  15. Radiofrequency ablation of surface v/s intraparenchymal hepatocellular carcinoma in cirrhotic patients

    Directory of Open Access Journals (Sweden)

    Yashwant Patidar

    2017-01-01

    Full Text Available Objective: To retrospectively evaluate the safety and technical efficacy of percutaneous radiofrequency ablation (RFA of surface hepatocellular carcinoma (HCC in comparison to intraparenchymal HCC in cirrhotic patients. Materials and Methods: Surface lesions were defined as tumours located or reaching within 1cm of liver capsule including exophytic lesions. Seventy-four surface HCC including 21 exophytic in 58 patients (surface group and 60 intraparenchymal HCC in 54 patients (intraparenchymal group measuring up to 4 cm in maximum extent underwent percutaneous [ultrasound (US or computed tomography-guided (CT-guided] RFA. The response to the treatment was assessed by contrast enhanced CT/magnetic resonance imaging (MRI done at 1, 3, 6, 9, and 12 months of RFA and thereafter every 4–6 months. In case of features suggesting residual disease, a repeat RFA was performed. The technical success after single-session RFA, complications and disease recurrence rates were calculated and compared between two groups. Results: Technical success achieved after first session of RFA in surface HCC was 95% (70/74 and intraparenchymal HCC was 97% (58/60. Hundred percent secondary success rate was achieved in both groups after second repeat RFA in residual lesion. No major difference in complication and local recurrence rate in both group on follow-up in surface HCC and intraparenchymal HCC. No case of needle track, peritoneal seeding, and treatment mortality was found. Conclusions: The complication rate and efficacy of RFA for surface and exophytic HCC's were comparable to that of intraparenchymal HCC. Hence surface and exophytic lesions should not be considered a contraindication for RFA in cirrhotic patients.

  16. Percutaneous Endovascular Radiofrequency Ablation for Malignant Portal Obstruction: An Initial Clinical Experience

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tian-Tian, E-mail: matthewwu1979@126.com [The 309th Hospital of PLA, Hepatobiliary Surgery Department (China); Li, Hu-Cheng, E-mail: hucheng-li-surgery@126.com [The 307th Hospital of PLA, General Surgery Department (China); Zheng, Fang, E-mail: fang-zheng-surgery@126.com [The 309th Hospital of PLA, Hepatobiliary Surgery Department (China); Ao, Guo-Kun, E-mail: guokun-ao-radiology@126.com; Lin, Hu, E-mail: hu-lin-radiology@126.com [The 309th Hospital of PLA, Radiology Department (China); Li, Wei-Min, E-mail: weimin-li-surgery@126.com [The 309th Hospital of PLA, Hepatobiliary Surgery Department (China)

    2016-07-15

    PurposeThe Habib™ VesOpen Catheter is a new endovascular radiofrequency ablation (RFA) device used to treat malignant portal obstruction. The purpose of this study was to evaluate the clinical feasibility and safety of RFA with this device.MethodsWe collected the clinical records and follow-up data of patients with malignant portal obstruction treated with percutaneous endovascular portal RFA using the Habib™ VesOpen Catheter. Procedure-related complications, improvement of symptoms, portal patency, survival, and postoperative biochemical tests were investigated.ResultsThe 31 patients enrolled in the study underwent 41 successful endovascular portal RFA procedures. Patients were divided into a portal-stenting (PS) group (n = 13), which underwent subsequent portal stenting with self-expandable metallic stents, and a non-stenting (NS) group (n = 18), which did not undergo stenting. No procedure-related abdominal hemorrhage or portal rupture occurred. Postablation complications included abdominal pain (n = 26), fever (n = 13), and pleural effusion (n = 15). Improvements in clinical manifestations were observed in 27 of the 31 patients. Of the 17 patients experiencing portal restenosis, 10 underwent successful repeat RFA. The rate of successful repeat RFA was significantly higher in the NS group than in the PS group. Median portal patency was shorter in the PS group than in the NS group. No mortality occurred during the 4 weeks after percutaneous endovascular portal RFA.ConclusionsPercutaneous endovascular portal RFA is a feasible and safe therapeutic option for malignant portal obstruction. Prospective investigations should be performed to evaluate clinical efficacy, in particular, the need to evaluate the necessity for subsequent portal stenting.

  17. Comparison of Mono- and Bipolar Radiofrequency Ablation in Benign Thyroid Disease.

    Science.gov (United States)

    Korkusuz, Yücel; Mader, Alexander; Gröner, Daniel; Ahmad, Shadi; Mader, Oscar Maximilian; Grünwald, Frank; Happel, Christian

    2017-05-04

    Radiofrequency ablation (RFA) is an approved minimal invasive method for the treatment of benign thyroid nodules. Several experimental, mainly ex vivo animal studies have compared the effectiveness of different RFA procedures in liver tissue. The aim of this retrospective clinical study was to evaluate the difference between monopolar and bipolar RFA in thyroid tissue considering thyroid volume reduction, patient discomfort and ultrasound evaluation. Eighteen patients with symptomatic complex benign thyroid nodules were treated in a single RFA session. Nine patients were treated with monopolar RFA, and nine other patients were treated with bipolar RFA. All patients underwent assessments before therapy and at 3-month follow-up (3MFU) including a complete hormone status (T3, T4, TSH, TG, TPOAb, TgAb, TRAb) and several ultrasound (US) evaluations using B-mode and color-coded Doppler imaging. The US evaluations contained measurement of volume, US Doppler, US echogenicity and US elastography. Additionally, applied energy (kJ), power output (W), number of shots (N) and total treatment time (s) were recorded in every case. Monopolar RFA resulted in a significant (p  0.05). Monopolar RFA did not lead to any significant changes concerning the US scores, whereas bipolar RFA led to a significant (p applied energy, treatment time, power output and number of shots (p > 0.05). Bipolar RFA did not show any disadvantages in comparison with monopolar RFA in the treatment of benign thyroid nodules. It shows better performance in terms of volume reduction and is superior when it comes to feasibility and patient discomfort. The recent study confirms the good ex vivo results for bipolar RFA.

  18. Frequency of and predictive factors for vascular invasion after radiofrequency ablation for hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Yoshinari Asaoka

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

  19. Cost-effectiveness of hepatic resection versus percutaneous radiofrequency ablation for early hepatocellular carcinoma.

    Science.gov (United States)

    Cucchetti, Alessandro; Piscaglia, Fabio; Cescon, Matteo; Colecchia, Antonio; Ercolani, Giorgio; Bolondi, Luigi; Pinna, Antonio D

    2013-08-01

    Both hepatic resection and radiofrequency ablation (RFA) are considered curative treatments for hepatocellular carcinoma (HCC), but their economic impact still remains not determined. Aim of the present study was to analyze the cost-effectiveness (CE) of these two strategies in early stage HCC (Milan criteria). As first step, a meta-analysis of the pertinent literature of the last decade was performed. Seventeen studies fulfilled the inclusion criteria: 3996 patients underwent resection and 4424 underwent RFA for early HCC. Data obtained from the meta-analysis were used to construct a Markov model. Costs were assessed from the health care provider perspective. A Monte Carlo probabilistic sensitivity analysis was used to estimate outcomes with distribution samples of 1000 patients for each treatment arm. In a 10-year perspective, for very early HCC (single nodule cost than resection and was the most cost-effective therapeutic strategy. For single HCCs of 3-5 cm, resection provided better life-expectancy and was more cost-effective than RFA, at a willingness-to-pay above €4200 per quality-adjusted life-year. In the presence of two or three nodules ≤3 cm, life-expectancy and quality-adjusted life-expectancy were very similar between the two treatments, but cost-effectiveness was again in favour of RFA. For very early HCC and in the presence of two or three nodules ≤3 cm, RFA is more cost-effective than resection; for single larger early stage HCCs, surgical resection remains the best strategy to adopt as a result of better survival rates at an acceptable increase in cost. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  20. A methodology for constraining power in finite element modeling of radiofrequency ablation.

    Science.gov (United States)

    Jiang, Yansheng; Possebon, Ricardo; Mulier, Stefaan; Wang, Chong; Chen, Feng; Feng, Yuanbo; Xia, Qian; Liu, Yewei; Yin, Ting; Oyen, Raymond; Ni, Yicheng

    2017-07-01

    Radiofrequency ablation (RFA) is a minimally invasive thermal therapy for the treatment of cancer, hyperopia, and cardiac tachyarrhythmia. In RFA, the power delivered to the tissue is a key parameter. The objective of this study was to establish a methodology for the finite element modeling of RFA with constant power. Because of changes in the electric conductivity of tissue with temperature, a nonconventional boundary value problem arises in the mathematic modeling of RFA: neither the voltage (Dirichlet condition) nor the current (Neumann condition), but the power, that is, the product of voltage and current was prescribed on part of boundary. We solved the problem using Lagrange multiplier: the product of the voltage and current on the electrode surface is constrained to be equal to the Joule heating. We theoretically proved the equality between the product of the voltage and current on the surface of the electrode and the Joule heating in the domain. We also proved the well-posedness of the problem of solving the Laplace equation for the electric potential under a constant power constraint prescribed on the electrode surface. The Pennes bioheat transfer equation and the Laplace equation for electric potential augmented with the constraint of constant power were solved simultaneously using the Newton-Raphson algorithm. Three problems for validation were solved. Numerical results were compared either with an analytical solution deduced in this study or with results obtained by ANSYS or experiments. This work provides the finite element modeling of constant power RFA with a firm mathematical basis and opens pathway for achieving the optimal RFA power. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Radiofrequency ablation for early oesophageal squamous neoplasia: Outcomes form United Kingdom registry

    Science.gov (United States)

    Haidry, Rehan J; Butt, Mohammed A; Dunn, Jason; Banks, Matthew; Gupta, Abhinav; Smart, Howard; Bhandari, Pradeep; Smith, Lesley Ann; Willert, Robert; Fullarton, Grant; John, Morris; Di Pietro, Massimo; Penman, Ian; Novelli, Marco; Lovat, Laurence B

    2013-01-01

    AIM: To report outcomes on patients undergoing radiofrequency ablation (RFA) for early oesophageal squamous neoplasia from a National Registry. METHODS: A Prospective cohort study from 8 tertiary referral centres in the United Kingdom. Patients with squamous high grade dysplasia (HGD) and early squamous cell carcinoma (ESCC) confined to the mucosa were treated. Visible lesions were removed by endoscopic mucosal resection (EMR) before RFA. Following initial RFA treatment, patients were followed up 3 monthly. Residual flat dysplasia was treated with RFA until complete reversal dysplasia (CR-D) was achieved or progression to invasive Squamous cell cancer defined as infiltration into the submucosa layer or beyond. The main outcome measures were CR-D at 12 mo from start of treatment, long term durability, progression to cancer and adverse events. RESULTS: Twenty patients with squamous HGD/ESCC completed treatment protocol. Five patients (25%) had EMR before starting RFA treatment. CR-D was 50% at 12 mo with a median of 1 RFA treatment, mean 1.5 (range 1-3). Two further patients achieved CR-D with repeat RFA after this time. Eighty per cent with CR-D remain dysplasia free at latest biopsy, with median follow up 24 mo (IQR 17-54). Six of 20 patients (30%) progressed to invasive cancer at 1 year. Four patients (20%) required endoscopic dilatations for symptomatic structuring after treatment. Two of these patients have required serial dilatations thereafter for symptomatic dysphagia with a median of 4 dilatations per patient. The other 2 patients required only a single dilatation to achieve an adequate symptomatic response. One patient developed cancer during follow up after end of treatment protocol. CONCLUSION: The role of RFA in these patients remains unclear. In our series 50% patients responded at 12 mo. These figures are lower than limited published data. PMID:24106401

  2. Radiofrequency thermal ablation for pain control in patients with single painful bone metastasis from hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Carrafiello, Gianpaolo [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: gcarraf@tin.it; Lagana, Domenico [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: donlaga@gmail.com; Ianniello, Andrea [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: ianand@libero.it; Nicotera, Paolo [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: paolonicotera@virgilio.it; Fontana, Federico [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: fede.fontana@libero.it; Dizonno, Massimiliano [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: massimilianodizonno@libero.it; Cuffari, Salvatore [Service of Anaesthesiology and Palliative Care, University of Insubria, 21100 Varese (Italy)], E-mail: salvatore.cuffari@libero.it; Fugazzola, Carlo [Department of Radiology, Vascular and Interventional Radiology, University of Insubria, 21100 Varese (Italy)], E-mail: carlo.fugazzola@ospedale.varese.it

    2009-08-15

    Objective: The aim of this study was to assess the safety and the efficacy of radiofrequency thermal ablation (RFA) for pain relief and analgesics use reduction in two patients with painful bone metastases from hepatocellular carcinoma (HCC). Materials and methods: Two patients with lytic metastases from HCC located at the left superior ileo-pubic branch and at the middle arch of VII rib, performed RFA displacing a LeVeen Needle (3.5 and 4.0 cm diameter) under US (ultrasonography) and fluoroscopic guidance. Two methods were used to determine the response of both patients: the first method was to measure patient's worst pain with a Brief Pain Inventory (BPI) 1 day after the procedure, every week for 1 month, and thereafter at week 8 and 12 (total follow-up 3 months); Second method was to evaluate patient's analgesics use recorded at week 1, 4, 8 and 12. Analgesic medication use was translated into a morphine-equivalent dose. Results: The RFA were well tolerated by the patients who did not develop any complication. Both patients obtained substantial reduction of pain, which decreased from a mean score of 8 to approximately 2 in 4 weeks. In both patients we observed a reduction in the use of morphine dose-equivalent after a peak at week 1. CT (computed tomography) imaging, performed at 1 month after RFA, demonstrated that both procedures were technically successful and safe because consistent necrosis and no evidence for complications were observed. Conclusion: RFA provides a potential alternative method for palliation of painful osteolytic metastases from HCC; the procedure is safe, and the pain relief is substantial.

  3. Radiofrequency ablation in the treatment of osteoid osteoma-5-year experience

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Ralf-Thorsten [Institute of Clinical Radiology, Ludwig Maximilians-University, Campus Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)], E-mail: rthoffma@med.uni-muenchen.de; Jakobs, Tobias F. [Institute of Clinical Radiology, Ludwig Maximilians-University, Campus Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)], E-mail: tobias.jakobs@med.uni-muenchen.de; Kubisch, Constanze H. [Department of Medicine/Gastroenterology, Ludwig Maximilians-University, Campus Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)], E-mail: constanze.kubisch@med.uni-muenchen.de; Trumm, Christoph G. [Institute of Clinical Radiology, Ludwig Maximilians-University, Campus Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)], E-mail: christoph.trumm@med.uni-muenchen.de; Weber, Christof [Institute of Diagnostic and Interventional Radiology, Klinikum - Deggendorf, Perlasbergerstr. 41, 94469 Deggendorf (Germany)], E-mail: privat@christofweber.de; Duerr, Hans-Roland [Department of Orthopedic Surgery, Ludwig Maximilians-University, Campus Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)], E-mail: hduerr@med.uni-muenchen.de; Helmberger, Thomas K. [Institute of Radiology and Nuclear Medicine, Klinikum Bogenhausen, Englschalkinger Str. 77, 81925 Munich (Germany)], E-mail: thomas.helmberger@kh-bogenhausen.de; Reiser, Maximilian F. [Institute of Clinical Radiology, Ludwig Maximilians-University, Campus Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)], E-mail: maximilian.reiser@med.uni-muenchen.de

    2010-02-15

    Purpose: This study aimed to determine the success and complication rates of radiofrequency ablation (RFA) in treatment of osteoid osteoma (OO) and duration of pain relief. Furthermore value of bone biopsy prior to the RFA was evaluated. Materials and methods: Within 61 months 39 patients (23 male, 16 female, 7-53 years, mean 18.7 years, median 17 years) suffering from osteoid osteoma were treated. Lesions were located in femur (n = 20), tibia (n = 10), spine (n = 5), humerus (n = 1), radius (n = 1), talus (n = 1) and pelvis (n = 1). In children, RFA was performed under general anaesthesia, in adults conscious sedation was preferred. In 29 of 39 (74%) lesion biopsies were obtained. Cooling of skin was performed in OOs located in bones with minor soft tissue covering (tibia, radius) and saline flushing via an additional needle was performed if the OO was adjacent to nerval structures. Primary success rate, complications, symptom-free interval, follow-up and biopsy results were evaluated. Results: Within observation period (1-61 months; median: 32 months) 38 of 39 patients were successfully treated and had no more complaints. In 3 of 38 patients relapse occurred after 1, 14 and 32 months and RFA was repeated. Two major complications (broken drill, infection) and 2 minor complications (hematoma, prolonged pain) were observed. Biopsy was able to prove diagnosis in 14 of 29 (48%) cases. Conclusions: Biopsy prior to treatment is not mandatory due to a remarkable amount of false negative findings in clinically and morphologically unambiguous cases of OO. RFA is a highly effective, efficient, minimally invasive and safe method for the treatment of OO.

  4. Multicenter Prospective Clinical Series Evaluating Radiofrequency Ablation in the Treatment of Painful Spine Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Bagla, Sandeep, E-mail: sandeep.bagla@gmail.com [Vascular Institute of Virginia, LLC (United States); Sayed, Dawood [University of Kansas Medical Center (United States); Smirniotopoulos, John [New York Presbyterian Hospital/Weill Cornell Medical Center (United States); Brower, Jayson [Providence Sacred Heart Medical Center and Children’s Hospital (United States); Neal Rutledge, J. [Seton Medical Center (United States); Dick, Bradley [Suburban Hospital (United States); Carlisle, James [St. Mark’s Hospital (United States); Lekht, Ilya [University of Southern California (United States); Georgy, Bassem [San Diego Imaging (United States)

    2016-09-15

    BackgroundRadiofrequency ablation (RFA) of vertebral body metastases (VBM) has been reported as safe and effective in retrospective studies. This single-arm prospective multicenter clinical study evaluates RFA in the treatment of painful VBM.MethodsFifty patients with VBM were prospectively enrolled during a 13-month period at eight US centers under an IRB-approved study. Percutaneous RFA was performed under imaging guidance with cement augmentation at the discretion of the operator. Pain, disability and quality of life were evaluated at baseline, prior to discharge, days 3, 7, 30 and 90 using the Numerical Pain Rating Scale, Oswestry Disability Index (ODI), the Functional Assessment of Cancer Therapy-General 7 (FACT-G7) and Functional Assessment of Cancer Therapy Quality-of-Life Measurement in Patients with Bone Pain (FACT-BP). Adverse events were monitored throughout this time interval.ResultsTwenty-six male and 24 female patients (mean age 61.0) underwent 69 treatments (30 thoracic and 39 lumbar). Cement augmentation was performed in 96 % of reported levels. Significant improvement in mean scores for pain, disability and cancer-specific health-related quality of life from baseline to all time intervals was seen. NRPS improved from 5.9 to 2.1 (p < 0.0001). ODI improved from 52.9 to 37.0 (p < 0.08). FACT-G7 improved form 10.9 to 16.2 (p = 0.0001). FACT-BP improved from 22.6 to 38.9 (p < 0.001). No complications related to the procedure were reported.ConclusionRFA with cement augmentation safely and effectively reduces pain and disability rapidly, while increasing quality of life in patients suffering from vertebral body metastases.

  5. Successful Interventional Treatment for Arterioportal Fistula Caused by Radiofrequency Ablation for Hepatocellular Carcinoma

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    Naoya Kanogawa

    2014-12-01

    Full Text Available Radiofrequency ablation (RFA is commonly used as a treatment for small hepatocellular carcinoma (HCC. Although several complications such as intraperitoneal bleeding are often observed after RFA, hepatic arterioportal fistula (APF is a less frequently occurring complication. In this study, we describe two cases of APF caused by RFA, which was successfully occluded by an interventional approach. Case 1 involved a 68-year-old man with solitary HCC in segment VIII of the liver. Both contrast-enhanced computed tomography and color Doppler sonography indicated an APF between the anterosuperior branch of the right hepatic artery (A8 and the portal branch (P8. Concordant with these findings, digital subtraction angiography (DSA revealed an APF in segment VIII of the liver. Subsequently, the APF was successfully occluded by transarterial embolization (TAE using gelatin sponge particles. Case 2 involved a 67-year-old man with solitary HCC in segment VII of the liver. Although he developed obstructive jaundice because of hemobilia after RFA, it was improved by endoscopic nasobiliary drainage and the systemic administration of antibiotics. In addition, color Doppler sonography revealed a disturbed flow of the right branch of the portal vein. Similar to case 1, DSA showed an APF between A8 and P8. The APF was successfully embolized by TAE using microcoils. In conclusion, it appears that the formation of APF should be checked after RFA. It is preferable to treat RFA-induced APF promptly by an interventional approach to avoid secondary complications such as portal hypertension and liver dysfunction.

  6. Percutaneous radiofrequency ablation (RFA) or robotic radiosurgery (RRS) for salvage treatment of colorectal liver metastases

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    Stintzing, Sebastian; Hendrich, Saskia; Heinemann, Volker [Dept. of Medical Oncology and Comprehensive Cancer Center, Klinikum Grosshadern, LMU, Munich (Germany)], E-mail: sebastian.stintzing@med.uni-muenchen.de; Grothe, Alexander; Trumm, Christoph G. [Dept. of Clinical Radiology, Univ. Hospital Grosshadern, LMU Munich, Munich (Germany); Hoffmann, Ralf-Thorsten [Dept. and Policlinics of Diagnostic Radiology, Universitaetsklinikum Carl Gustav Carus Dresden (Germany); Rentsch, Markus [Dept. of Surgery, Univ. Hospital Grosshadern, LMU Munich, Munich (Germany); Fuerweger, Christoph; Muacevic, Alexander [European Cyberknife Center Munich, Munich (Germany)

    2013-06-15

    Background. Stereotactic radiation therapy is an evolving modality to treat otherwise unresectable liver metastases. In this analysis, two local therapies: 1) single session robotic radiosurgery (RRS) and 2) percutaneous radiofrequency ablation (RFA) were compared in a total of 60 heavily pretreated colorectal cancer patients. Methods. Thirty patients with a total of 35 colorectal liver metastases not qualifying for surgery that were treated in curative intent with RRS were prospectively followed. To compare efficacy of both treatment modalities, patients treated with RFA during the same period of time were matched according to number and size of the treated lesions. Local tumor control, local disease free survival (DFS), and freedom from distant recurrence (FFDR) were analyzed for effi cacy. Treatment-related side effects were recorded for comparison. Results. The median diameter of the treated lesions was 33 mm (7-53 mm). Baseline characteristics did not differ significantly between the groups. One- and two-year local control rates showed no signifi cant difference but favored RRS (85% vs. 65% and 80% vs. 61%, respectively). A signifi cantly longer local DFS of patients treated with RRS compared to RFA (34.4 months vs. 6.0 months; p 0.001) was found. Both, median FFDR (11.4 months for RRS vs. 7.1 months for RFA p=0.25) and the recurrence rate (67% for RRS and 63% for RFA, p>0.99) were comparable. Conclusion. Single session RRS is a safe and effective method to treat colorectal liver metastases. In this analysis, a trend towards longer DFS was seen in patients treated with RRS when compared to RFA.

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

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    Narayanan, Govindarajan, E-mail: gnarayanan@med.miami.edu; Froud, Tatiana, E-mail: tfroud@med.miami.edu [Miller School of Medicine, University of Miami, Department of Vascular and Interventional Radiology (United States); Lo, Kaming, E-mail: KLo@biostat.med.miami.edu [Miller School of Medicine, University of Miami, Department of Epidemiology and Public Health (United States); Barbery, Katuska J., E-mail: kbarbery@med.miami.edu; Perez-Rojas, Evelyn, E-mail: eprojas@med.miami.edu; Yrizarry, Jose, E-mail: jyrizarr@med.miami.edu [Miller School of Medicine, University of Miami, Department of Vascular and Interventional Radiology (United States)

    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.

  8. Frequency, risk factors and survival associated with an intrasubsegmental recurrence after radiofrequency ablation for hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Ryosuke Tateishi

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

  9. Prospective study of percutaneous radiofrequency nerve ablation for chronic plantar fasciitis.

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    Erken, H Yener; Ayanoglu, Semih; Akmaz, Ibrahim; Erler, Kaan; Kiral, Ahmet

    2014-02-01

    Chronic plantar heel pain is one of the most painful foot conditions and is generally associated with plantar fasciitis. This study reports 2-year follow-up results of radiofrequency nerve ablation (RFNA) of the calcaneal branches of the inferior calcaneal nerve in patients with chronic heel pain associated with plantar fasciitis. After receiving approval from the institutional review board, we prospectively evaluated the results of the RFNA of the calcaneal branches of the inferior calcaneal nerve on 35 feet in 29 patients with plantar heel pain between 2008 and 2011. All of the patients who were treated had been complaining of heel pain for more than 6 months and had failed conservative treatment. All of the patients were evaluated (quantitatively) using the average 10-point Visual Analog Scale (VAS) before treatment, as well as at their 1-month, 1-year, and 2-year follow-up after the procedure. We also evaluated 26 feet in 20 patients with American Orthopaedic Foot and Ankle Society scale (AOFAS) scores before the treatment, as well as at their 1-month, 1-year, and 2-year follow-up after the procedure. The average VAS score of the feet was 9.2 ± 1.9 before treatment, 0.5 ± 1.3 at 1 month after the procedure, 1.5 ± 2.1 at 1-year follow-up, and 1.3 ± 1.8 at 2-year follow-up (P plantar fasciitis that did not respond to other conservative treatment options. Level IV, retrospective case series.

  10. Effects and Mechanisms of Radiofrequency Ablation of Renal Sympathetic Nerve on Anti-Hypertension in Canine

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    Wei Chen

    Full Text Available Abstract Background: Radiofrequency ablation of renal sympathetic nerve (RDN shows effective BP reduction in hypertensive patients while the specific mechanisms remain unclear. Objective: We hypothesized that abnormal levels of norepinephrine (NE and changes in NE-related enzymes and angiotensinconverting enzyme 2 (ACE2, angiotensin (Ang-(1-7 and Mas receptor mediate the anti-hypertensive effects of RDN. Methods: Mean values of systolic blood pressure (SBP, diastolic blood pressure (DBP and mean arterial pressure (MAP were assessed at baseline and follow-up. Plasma and renal norepinephrine (NE concentrations were determined using highperformance liquid chromatography with electrochemical detection, and levels of NE-related enzyme and ACE2-Ang(1-7- Mas were measured using real time PCR, Western blot and immunohistochemistry or Elisa in a hypertensive canine model fed with high-fat diet and treated with RDN. The parameters were also determined in a sham group treated with renal arteriography and a control group fed with normal diet. Results: RDN decreased SBP, DBP, MAP, plasma and renal NE. Compared with the sham group, renal tyrosine hydroxylase (TH expression was lower and renalase expression was higher in the RDN group. Compared with the control group, renal TH and catechol-o-methyl transferase (COMT were higher and renalase was lower in the sham group. Moreover, renal ACE2, Ang-(1-7 and Mas levels of the RDN group were higher than those of the sham group, which were lower than those of the control group. Conclusion: RDN shows anti-hypertensive effect with reduced NE and activation of ACE2-Ang(1-7-Mas, indicating that it may contribute to the anti-hypertensive effect of RDN.

  11. Serum alpha-fetoprotein response can predict prognosis in hepatocellular carcinoma patients undergoing radiofrequency ablation therapy

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    Kao, W.-Y. [Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taiwan (China); Chiou, Y.-Y., E-mail: yychiou@vghtpe.gov.tw [Department of Radiology, Taipei Veterans General Hospital, Taiwan (China); Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Hung, H.-H. [Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taiwan (China); Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Su, C.-W., E-mail: cwsu2@vghtpe.gov.tw [Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taiwan (China); Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Chou, Y.-H. [Department of Radiology, Taipei Veterans General Hospital, Taiwan (China); Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Wu, J.-C. [Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Medical Research and Education, Taipei Veterans General Hospital, Taiwan (China); Huo, T.-I. [Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Huang, Y.-H. [Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taiwan (China); Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Wu, W.-C. [Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taiwan (China)

    2012-05-15

    Aims: To evaluate the clinical inference of serum alpha-fetoprotein (AFP) response in hepatocellular carcinoma (HCC) patients undergoing percutaneous radiofrequency ablation (RFA). Materials and methods: Three hundred and thirteen previously untreated HCC patients were enrolled in the study. The optimal AFP response was defined as >20% decrease from baseline after 1 month of RFA for those with a baseline AFP level of {>=}100 ng/ml. The impact of AFP response on prognosis was analysed and prognostic factors were assessed. Results: After a median follow-up of 26.7 {+-} 19.1 months, 49 patients died and 264 patients were alive. The cumulative 5 year survival rates were 75.3 and 57.4% in patients with an initial AFP of <100 ng/ml and {>=}100 ng/ml, respectively (p = 0.003). In the 58 patients with a baseline AFP of {>=}100 ng/ml and initial completed tumour necrosis after RFA, the cumulative 5 year survival rates were 62.4 and 25.7% in optimal and non-optimal AFP responders, respectively (p = 0.001). By multivariate analysis, the prothrombin time international normalized ratio >1.1 (p = 0.009), non-optimal AFP response (p = 0.023), and creatinine >1.5 mg/dl (p = 0.021) were independent risk factors predictive of poor overall survival. Besides, the cumulative 5 year recurrence rates were 83.4 and 100% in optimal and non-optimal AFP responders, respectively (p < 0.001). Multivariate analysis demonstrated platelet count {<=}10{sup 5}/mm{sup 3} (p = 0.048), tumour size >2 cm (p = 0.027), and non-optimal AFP response (p < 0.001) were independent risk factors associated with tumour recurrence after RFA. Conclusions: Serum AFP response may be a useful marker for predicting prognosis in HCC patients undergoing RFA.

  12. Low-power bipolar radiofrequency ablation and vertebral augmentation for the palliative treatment of spinal malignancies.

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    Cazzato, Roberto Luigi; Garnon, Julien; Caudrelier, Jean; Rao, Pramod Prabhakar; Koch, Guillaume; Gangi, Afshin

    2018-01-18

    To investigate the analgesic properties and the safety of low power bipolar radiofrequency ablation (RFA) performed with internally cooled electrodes and vertebral augmentation for the treatment of painful spinal malignancies. Consent was waived for retrospective study participation. Review of electronic records identified 11 consecutive patients (6 females; 5 males; mean age 61.3 ± 11.6 years) with one-index painful spinal tumour, who were treated between June 2016 and October 2017 with bipolar RFA and vertebral augmentation. Patients were treated if they presented with focal pain (≥4/10 on a 0-10 visual analogic scale in the 24-h period) corresponding to a metastatic vertebral level on cross sectional imaging. The Wilcoxon test was used to evaluate the significance of the post-operative pain. Lumbar levels were treated in 72.7% cases; metastatic epidural involvement was noted in 81.8% cases; 54.5% patients received associated treatments in addition to RFA, which was coupled to vertebral augmentation in all cases. Two (18.2%) complications were noted. Mean pain score measured at last clinical follow-up available (mean 1.9 ± 1.4 months) was 3.5 ± 2 (versus 7.8 ± 1.1 at baseline; p <0.01). Low-power bipolar RFA performed with internally cooled electrodes and coupled to vertebral augmentation provides safe and effective early analgesia in patients affected by painful spinal malignancies.

  13. Effect of Radiofrequency Thermal Ablation Treatment on Nasal Ciliary Motility: A Study with Phase-Contrast Microscopy.

    Science.gov (United States)

    Rosato, Chiara; Pagliuca, Giulio; Martellucci, Salvatore; de Vincentiis, Marco; Greco, Antonio; Fusconi, Massimo; De Virgilio, Armando; Gallipoli, Camilla; Simonelli, Marilia; Gallo, Andrea

    2016-04-01

    To investigate the efficacy of nasal ciliary motility after radiofrequency ablation treatment in patients with isolated inferior turbinate hypertrophy and to clarify how long until normal ciliary function is restored. Prospective, single-group, pretest-posttest design. Academic tertiary care medical center. This study involved 34 adult patients affected by nasal obstruction due to inferior turbinate hypertrophy who underwent radiofrequency ablation treatment between June and December 2014. Diagnosis was assessed according to clinical history, nasal endoscopy, and active anterior rhinomanometry. Cytologic samples were collected by nasal scraping before surgery and 1, 2, and 3 months after surgery. Ciliary motility was evaluated by nasal cytology with phase-contrast microscopy. Functional aspects of nasal mucosa were studied, with a focus on 3 parameters: (1) nasal mucociliary clearance, assessed by saccharin nasal transit time test; (2) percentage of ciliated cell motility, measured as the ratio between cells with motility and cells without motility; and (3) efficacy of ciliary motility, measured as the ratio between cells with valid motility and cells with hypovalid motility. Ciliary motility and ciliary efficacy showed a significant reduction after 1 and 2 months from surgery, returning to normal values within 3 months. No significant changes in saccharin nasal transit time were recorded during the follow-up. The outcomes of this study suggest that radiofrequency ablation treatment causes ciliary motility changes of nasal mucosa that are completely restored after at least 3 months after surgery. These cytologic abnormalities do not affect nasal functionality. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  14. CT-guided radiofrequency (RF) ablation of osteoid osteoma. Clinical long-term results; CT-gesteuerte Radiofrequenz(RF)-Ablation von Osteoidosteomen. Klinische Langzeitergebnisse

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    Schmidt, Diethard; Clasen, S.; Schaefer, J.F.; Rempp, H.; Koenig, C.W.; Claussen, C.D. [Universitaetsklinikum Tuebingen (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Duda, S.; Truebenbach, J. [Juedisches Krankenhaus, Berlin (Germany). Radiologen Praxis; Erdtmann, B. [Radiologie Zentrum Stuttgart, Bad Cannstatt (Germany). Praxis; Pereira, P.L. [SLK-Kliniken, Heilbronn (Germany). Klinik fuer Radiologie, Minimal-Invasive Therapien und Nuklearmedizin

    2011-04-15

    Purpose: To evaluate CT-guided radiofrequency (RF) ablation of osteoid osteoma using internally cooled monopolar RF electrodes for technical success, complications and clinical long-term success. Materials and Methods: Between April 1999 and July 2009, 23 patients were treated under general anesthesia with CT-guided RF ablation using an internally cooled monopolar single RF electrode (Cool-tip, Valleylab, TycoHealthcare, Boulder, USA; active tip: 10 mm). For the removal of the nidus, we used either a manual or an automated drill. The technical success was evaluated by a CT scan (MSCT, Siemens Medical Solutions, Forchheim). The clinical long-term success was investigated by questioning patients prior to discharge, and after 6, 12 and 18 months. After 18 months, patients were interviewed on an annual basis. Results: The technical success rate was 100 %. The nidus was located in n = 19 cases at the lower extremity and in n = 4 cases at the upper extremity. Minor complications were observed for n = 2 patients. The mean hospitalization time was 1.5 d (1-2 d). The mean follow-up was 75.9 months (18-120 months) for n = 23 patients. No local recurrence was observed. One patient had intermediate pain one week after RF ablation without recurrent symptoms. Conclusion: CT-guided RF ablation using an internally cooled monopolar single RF electrode is an effective and safe minimally invasive method for the treatment of osteoid osteoma with excellent clinical long-term success. (orig.)

  15. Cold saline irrigation of the renal pelvis during Radiofrequency Ablation of a central renal neoplasm: a case report

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    Morales Jose P

    2008-02-01

    Full Text Available Abstract Introduction Thermal destruction mediated by radiofrequency ablation (RFA is gaining attention as an alternative treatment for patients with renal cell carcinoma (RCC, particularly in those who are not candidates for open surgery. Treatment of central tumours is occasionally associated with complications such as ureteric stricture, injury to the psoas muscle, haematuria and vascular laceration. Case presentation We have used infusion of cold saline during RFA, through a retrograde ureteric catheter with its tip in the renal pelvis, in a patient with a central renal tumour. Conclusion We believe this process to have successfully avoided the risk of thermal injury.

  16. How I do it-optimizing radiofrequency ablation in spinal metastases using iCT and navigation.

    Science.gov (United States)

    Kavakebi, Pujan; Freyschlag, C F; Thomé, C

    2017-10-01

    Exact positioning of the radiofrequency ablation (RFA) probe for tumor treatment under fluoroscopic guidance can be difficult because of potentially small inaccessible lesions and the radiation dose to the medical staff in RFA. In addition, vertebroplasty (VP) can be significantly high. Description and workflow of RFA in spinal metastasis using iCT (intraoperative computed tomography) and 3D-navigation-based probe placement followed by VP. RFA and VP can be successfully combined with iCT-based navigation, which leads to a reduction of radiation to the staff and optimal probe positioning due to 3D navigation.

  17. Idiopathic left ventricular tachycardia with a change from left to right axis deviation during radiofrequency catheter ablation.

    Science.gov (United States)

    Okumura, Yasuo; Watanabe, Ichiro; Ohkubo, Kimie; Hashimoto, Kenichi; Ashino, Sonoko; Kofune, Masayoshi; Sugimura, Hidezou; Shindo, Atsushi; Nakai, Toshiko; Saito, Satoshi

    2006-05-01

    A 62 year-old-woman presented with a right bundle branch block (RBBB) and left axis deviation (LAD) tachycardia. Radiofrequency (RF) energy was delivered to the left posterior fascicle (LPF) where 2 presystolic Purkinje potentials (P1 and P2) preceding onset of the QRS complex were recorded. During RF energy applications, the QRS morphology of the tachycardia changed from RBBB and LAD to RBBB and right axis deviation without termination of the tachycardia. The Purkinje potential was observed following the QRS complex during the tachycardia because of conduction block of the LPF distal to the reentry circuit due to RF catheter ablation.

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

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    Aksu T

    2015-02-01

    Full Text Available Tolga Aksu, Tumer Erdem Guler, Ebru Golcuk, Ismail Erden, Kazim Serhan Ozcan Department of Cardiology, Kocaeli Derince Education and Research Hospital, Derince, Kocaeli, Turkey Abstract: 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. Keywords: dextrocardia, AVNRT, ablation, pulmonary agenesis

  19. Recovery of cardiomyopathy induced by ventricular premature beats of paraHisian origin after successful radiofrequency catheter ablation.

    Science.gov (United States)

    Aksan, Gökhan; Elitok, Ali; Tezcan, Mehmet; Bilge, Ahmet Kaya; Adalet, Kamil

    2017-12-01

    A 51-year-old male patient presented with frequent and symptomatic premature ventricular complexes (PVCs) that had induced cardiomyopathy. Radiofrequency (RF) catheter ablation of the origin of the PVCs was planned and the patient underwent electrophysiological study. During activation mapping, the earliest ventricular activation was identified at the His bundle region. Small His bundle electrogram recording by the distal ablation electrode during sinus rhythm revealed that the earliest ventricular activation during PVC preceded the QRS onset by 58 milliseconds. The PVCs were successfully eliminated without occurrence of atrioventricular block using incremental application of RF energy to the para-Hisian region. At the conclusion of a 5-month follow-up period, the patient remained asymptomatic and transthoracic echocardiography demonstrated an improvement in left ventricular ejection fraction.

  20. Massive Hepatic Infarction After Pure Ethanol Injection and Radiofrequency Ablation Therapy for Hepatocellular Carcinoma: A Case Report

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    Yen-Cheng Chiu

    2009-03-01

    Full Text Available Hepatic infarction is a rare complication of radiofrequency ablation (RFA for hepatocellular carcinoma. Hepatic infarction is thought to be caused by injury to either the hepatic arterial system or to both the hepatic arterial and portal venous supply. The efficacy of RFA is reduced in the presence of nearby vessels larger than 3 mm in diameter due to a heat-sink effect. Such an effect can be diminished by performing percutaneous pure ethanol injection prior to RFA. Although larger vessels are unlikely to be ablated or obliterated by RFA alone, it can happen and cause massive liver damage, particularly if RFA was preceded by other therapies such as percutaneous pure ethanol injection and/or transcatheter arterial embolization. Here, we report a case of massive liver infarction after sequential use of both treatment modalities for hepatocellular carcinoma.

  1. Fiber-optic combined FPI/FBG sensors for monitoring of radiofrequency thermal ablation of liver tumors: ex vivo experiments.

    Science.gov (United States)

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

    2014-04-01

    We present a biocompatible, all-glass, 0.2 mm diameter, fiber-optic probe that combines an extrinsic Fabry-Perot interferometry and a proximal fiber Bragg grating sensor; the probe enables dual pressure and temperature measurement on an active 4 mm length, with 40 Pa and 0.2°C nominal accuracy. The sensing system has been applied to monitor online the radiofrequency thermal ablation of tumors in liver tissue. Preliminary experiments have been performed in a reference chamber with uniform heating; further experiments have been carried out on ex vivo porcine liver, which allowed the measurement of a steep temperature gradient and monitoring of the local pressure increase during the ablation procedure.

  2. Teflon-buttressed sutures plus pericardium patch repair left ventricular rupture caused by radiofrequency catheter ablation: A case report.

    Science.gov (United States)

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

    2016-09-01

    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. 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. 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. Timely surgical intervention under CPB facilitated the survival of the patient. Teflon-buttressed sutures plus pericardium patch achieved the successful repair of the rupture.

  3. Biliary obstruction caused by intra-biliary tumor growth from recurred hepatocellular carcinoma after radiofrequency ablation: Case report

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    Yi, Ji Hyun; Kim, Jae Won [Dept. of Radiology, Yeungnam University College of Medicine, Daegu (Korea, Republic of)

    2014-04-15

    A 59-year-old man with a known central hepatocellular carcinoma (HCC) underwent a trans-arterial-chemo-embolization (TACE) and a post-TACE percutaneous radiofrequency ablation (PRFA). Two months after the PRFA, the patient presented jaundice and an abdominal computed tomography was obtained. An arterial enhancing mass adjacent to the ablated necrotic lesion with a continuously coexisting mass inside the right hepatic duct, suggestive of a HCC recurrence with a direct extension to the biliary tract was found. Finally a biliary tumor obstruction has been developed and a percutaneous transhepatic biliary drainage was performed. This case of biliary obstruction caused by directly invaded recurred HCC after PRFA will be reported because of its rare occurrence.

  4. Percutaneous ultrasound-guided radiofrequency ablation with artificial pleural effusion for hepatocellular carcinoma in the hepatic dome.

    Science.gov (United States)

    Minami, Yasunori; Kudo, Masatoshi; Kawasaki, Toshihiko; Chung, Hobyung; Ogawa, Chikara; Inoue, Tatsuo; Sakaguchi, Yasuhiro; Sakamoto, Hiroki; Shiozaki, Hitoshi

    2003-01-01

    Nodules of hepatocellular carcinoma (HCC) located in the hepatic dome cannot be depicted on ultrasography because of pulmonary air. Therefore, percutaneous treatment is not possible in such cases. The purpose of this study was to clarify the feasibility and safety of percutaneous sonographically guided radiofrequency (RF) ablation with the concurrent use of artificial pleural effusion for HCC located in the right subphrenic region. Between May 2001 and June 2002, 24 patients with 28 HCC nodules located directly below the diaphragm were enrolled in this study. The patient population included 17 men and 7 women (age range, 51-87 years; mean age, 66.5 years). The maximum diameter of the HCC nodules ranged from 1.0 cm to 4 cm (mean +/- SD, 2.1 +/- 0.8 cm). We infused 200-1100 ml of 5% glucose solution intrathoracically to separate the lung and liver; thus, obtaining an image of the whole tumor was impossible on gray-scale sonography. Complete tumor necrosis was achieved in a single session of RF ablation in 27 (96.4%) of the 28 lesions, while two sessions of RF ablation were required for the remaining lesion (3.6%). During treatment, no dyspnea or other complications concerned with the respiratory system were observed. Clinical courses have been satisfactory without recurrences at 1-13 months after treatment (mean, 7.9 months). Percutaneous RF ablation with artificial pleural effusion in patients with HCC in the hepatic dome may be a safe and feasible therapy.

  5. Unintended Thermal Injuries from Radiofrequency Ablation: Organ Protection with an Angioplasty Balloon Catheter in an Animal Model

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    Martha-Grace Knuttinen

    2014-01-01

    Full Text Available Objectives: The aim of this study was to investigate a novel approach of using a balloon catheter as a protective device to separate liver from the diaphragm or nearby bowel during radiofrequency ablation (RFA of hepatic dome tumors in an animal model. Materials and Methods: All experimental procedures were approved by animal Institutional Review Board. Using a 3 cm RF needle electrode, 70 hepatic ablation zones were created using ultrasound in 7 pigs. 50 lesions were created using balloon interposition between liver and diaphragm; 20 lesions were created using the balloon device interposed posteriorly between liver and bowel. Additional 21 control lesions were performed. Animals were sacrificed immediately; diaphragm and bowel were then visually inspected and sectioned. Diaphragmatic and bowel injury was then classified according to the depth of thickness. Results: Control lesions caused full thickness injury, either to diaphragm or bowel. During ablation of lesions with balloon interposition, there was significantly less diaphragmatic injury, P < 0.001 and less bowel injury, P < 0.01. Conclusion: Using balloon interposition as a protective device has advantages over previous saline infusion or CO 2 insufflation, providing a safe way to expand percutaneous RFA of liver tumors located on the undersurface of the diaphragm. In addition, this method may be used in protection of other organs adjacent to areas being ablated.

  6. Radiofrequency ablation of small liver malignancies under magnetic resonance guidance: progress in targeting and preliminary observations with temperature monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Terraz, Sylvain; Cernicanu, Alexandru; Lepetit-Coiffe, Matthieu; Viallon, Magalie; Salomir, Rares; Becker, Christoph D. [University Hospitals of Geneva, Department of Radiology, Geneva 14 (Switzerland); Mentha, Gilles [University Hospitals of Geneva, Department of Visceral Surgery and Transplantation, Geneva (Switzerland)

    2010-04-15

    To evaluate the feasibility and effectiveness of magnetic resonance (MR)-guided radiofrequency (RF) ablation for small liver tumours with poor conspicuity on both contrast-enhanced ultrasonography (US) and computed tomography (CT), using fast navigation and temperature monitoring. Sixteen malignant liver nodules (long-axis diameter, 0.6-2.4 cm) were treated with multipolar RF ablation on a 1.5-T wide-bore MR system in ten patients. Targeting was performed interactively, using a fast steady-state free precession sequence. Real-time MR-based temperature mapping was performed, using gradient echo-echo planar imaging (GRE-EPI) and hardware filtering. MR-specific treatment data were recorded. The mean follow-up time was 19 {+-} 7 months. Correct placement of RF electrodes was obtained in all procedures (image update, <500 ms; mean targeting time, 21 {+-} 11 min). MR thermometry was available for 14 of 16 nodules (88%) with an accuracy of 1.6 C in a non-heated region. No correlation was found between the size of the lethal thermal dose and the ablation zone at follow-up imaging. The primary and secondary effectiveness rates were 100% and 91%, respectively. RF ablation of small liver tumours can be planned, targeted, monitored and controlled with MR imaging within acceptable procedure times. Temperature mapping is technically feasible, but the clinical benefit remains to be proven. (orig.)

  7. Effect of variable heat transfer coefficient on tissue temperature next to a large vessel during radiofrequency tumor ablation

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    Pinheiro Cleber

    2008-07-01

    Full Text Available Abstract Background One of the current shortcomings of radiofrequency (RF tumor ablation is its limited performance in regions close to large blood vessels, resulting in high recurrence rates at these locations. Computer models have been used to determine tissue temperatures during tumor ablation procedures. To simulate large vessels, either constant wall temperature or constant convective heat transfer coefficient (h have been assumed at the vessel surface to simulate convection. However, the actual distribution of the temperature on the vessel wall is non-uniform and time-varying, and this feature makes the convective coefficient variable. Methods This paper presents a realistic time-varying model in which h is a function of the temperature distribution at the vessel wall. The finite-element method (FEM was employed in order to model RF hepatic ablation. Two geometrical configurations were investigated. The RF electrode was placed at distances of 1 and 5 mm from a large vessel (10 mm diameter. Results When the ablation procedure takes longer than 1–2 min, the attained coagulation zone obtained with both time-varying h and constant h does not differ significantly. However, for short duration ablation (5–10 s and when the electrode is 1 mm away from the vessel, the use of constant h can lead to errors as high as 20% in the estimation of the coagulation zone. Conclusion For tumor ablation procedures typically lasting at least 5 min, this study shows that modeling the heat sink effect of large vessels by applying constant h as a boundary condition will yield precise results while reducing computational complexity. However, for other thermal therapies with shorter treatment using a time-varying h may be necessary.

  8. Effect of Radiofrequency Catheter Ablation on Quality of Life in Patients with Wolff-Parkinson-White Syndrome

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    Shokhrukh Erkaboev

    2015-09-01

    Full Text Available Wolff-Parkinson-White (WPW syndrome is one of several disorders of the conduction system of the heart that are commonly referred to as pre-excitation syndromes. As the syndrome significantly reduces the patients’ quality of life (QoL, the purpose of the current study was to compare QoL scores in patients with WPW syndrome before and after a radiofrequency catheter ablation (RFA procedure. To assess the patients’ QoL, the MOS 36-Item Short-Form Health Survey was used. Immediate and long-term outcomes of radiofrequency catheter ablation were analyzed in 60 patients diagnosed with WPW syndrome, 41(68.3% men and 19(31.7% women. As compared with the controls (28 apparently healthy persons, patients with WPW syndrome before RFA experienced significant reduction in both physical and mental health components. RFA was found effective in 93.3% of patients with WPW syndrome. At 3 months after RFA, patients showed significant improvement in both physical (13.5% and mental (17.2% health components; at 12 months, QoL parameters reached those of the controls.

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

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    Robinson, Trevor J G; 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.

  10. Comparison of percutaneous radiofrequency thermal ablation and surgical resection for small hepatocellular carcinoma

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    Nishikawa Hiroki

    2011-12-01

    Full Text Available Abstract Background The purpose of this investigation was to compare the outcome of percutaneous radiofrequency thermal ablation therapy (PRFA with surgical resection (SR in the treatment of single and small hepatocellular carcinoma (HCC. Methods We conducted a retrospective cohort study on 231 treatment naive patients with a single HCC ≤ 3 cm who had received either curative PRFA (162 patients or curative SR (69 patients. All patients were regularly followed up after treatment at our department with blood and radiologic tests. Results The 1-, 3- and 5-year overall survival rates after PRFA and SR were 95.4%, 79.6% and 63.1%, respectively in the PRFA group and 100%, 81.4% and 74.6%, respectively in the SR group. The corresponding recurrence free survival rates at 1, 3 and 5 years after PRFA and SR were 82.0%, 38.3% and 18.0%, respectively in the PRFA group and 86.0%, 47.2% and 26.0%, respectively in the SR group. In terms of overall survival and recurrence free survival, there were no significant differences between these two groups. In comparison of PRFA group patients with liver cirrhosis (LC (n = 127 and SR group patients with LC (n = 50 and in comparison of PRFA group patients without LC (n = 35 and SR group patients without LC (n = 19, there were also no significant differences between two groups in terms of overall survival and recurrence free survival. In the multivariate analysis of the risk factors contributing to overall survival, serum albumin level was the sole significant factor. In the multivariate analysis of the risk factors contributing to recurrence free survival, presence of LC was the sole significant factor. The rate of serious adverse events in the SR group was significantly higher than that in the PRFA group (P = 0.023. Hospitalization length in the SR group was significantly longer than in the PRFA group (P = 0.013. Conclusions PRFA is as effective as SR in the treatment of single and small HCC, and is less invasive

  11. Radiofrequency ablation versus resection for colorectal cancer liver metastases: a meta-analysis.

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    Mingzhe Weng

    Full Text Available BACKGROUND: No randomized controlled trial (RCT has yet been performed to provide the evidence to clarify the therapeutic debate on liver resection (LR and radiofrequency ablation (RFA in treating colorectal liver metastases (CLM. The meta-analysis was performed to summarize the evidence mostly from retrospective clinical trials and to investigate the effect of LR and RFA. METHODOLOGY/PRINCIPAL FINDINGS: Systematic literature search of clinical studies was carried out to compare RFA and LR for CLM in Pubmed, Embase and the Cochrane Library Central databases. The meta-analysis was performed using risk ratio (RR and random effect model, in which 95% confidence intervals (95% CI for RR were calculated. Primary outcomes were the overall survival (OS and disease-free survival (DFS at 3 and 5 years plus mortality and morbidity. 1 prospective study and 12 retrospective studies were finally eligible for meta-analysis. LR was significantly superior to RFA in 3 -year OS (RR 1.377, 95% CI: 1.246-1.522; 5-year OS (RR: 1.474, 95%CI: 1.284-1.692; 3-year DFS (RR 1.735, 95% CI: 1.483-2.029 and 5-year DFS (RR 2.227, 95% CI: 1.823-2.720. The postoperative morbidity was higher in LR (RR: 2.495, 95% CI: 1.881-3.308, but no significant difference was found in mortality between LR and RFA. The data from the 3 subgroups (tumor<3 cm; solitary tumor; open surgery or laparoscopic approach showed significantly better OS and DFS in patients who received surgical resection. CONCLUSIONS/SIGNIFICANCES: Although multiple confounders exist in the clinical trials especially the bias in patient selection, LR was significantly superior to RFA in the treatment of CLM, even when conditions limited to tumor<3 cm, solitary tumor and open surgery or laparoscopic (lap approach. Therefore, caution should be taken when treating CLM with RFA before more supportive evidences for RFA from RCTs are obtained.

  12. Real-time US-CT/MR fusion imaging for percutaneous radiofrequency ablation of hepatocellular carcinoma.

    Science.gov (United States)

    Ahn, Su Joa; Lee, Jeong Min; Lee, Dong Ho; Lee, Sang Min; Yoon, Jung-Hwan; Kim, Yoon Jun; Lee, Jeong-Hoon; Yu, Su Jong; Han, Joon Koo

    2017-02-01

    Although ultrasonography (US) guided radiofrequency ablation (RFA) is a commonly used treatment option for early hepatocellular carcinoma (HCC), inconspicuous tumors on US limits its feasibility. Thus, we prospectively determined whether real-time US-CT/MR fusion imaging can improve the technical feasibility of RFA compared with B-mode US, and help predict local tumor progression after RFA in patients with HCC. A total of 216 patients with 243 HCCs ⩽5cm referred for RFA were prospectively enrolled. Prior to RFA, the operators scored the visibility of tumors, and technical feasibility on a 4-point scale at both B-mode US and fusion imaging. RFA was performed with a switching monopolar system using a separable cluster electrode under fusion imaging guidance. Technique effectiveness, local tumor progression and intrahepatic remote recurrences were evaluated. Tumor visibility and technical feasibility were significantly improved with fusion imaging compared with B-mode US (pfusion imaging guidance, the technique effectiveness of RFA for invisible tumors on B-mode US was similar to those for visible tumors (96.1% vs. 97.6%, p=0.295). Estimated cumulative incidence of local tumor progression at 24months was 4.7%, and previous treatment for other hepatic tumors (p=0.01), higher expected number of electrode insertions needed and lower technical feasibility scores (pfusion imaging were significant negative predictive factors for local tumor progression. Real-time fusion imaging guidance significantly improved the tumor visibility and technical feasibility of RFA in patients with HCCs compared with B-mode US, and low feasibility scores on fusion imaging was a significant negative predictive factor for local tumor progression. US/CT-MR fusion imaging guidance improved the tumor visibility and technical feasibility of RFA in patients with HCCs. In addition, fusion imaging guided RFA using multiple electrodes demonstrated a high technique effectiveness rate and a low local

  13. Performance of a novel bipolar/monopolar radiofrequency ablation device on the beating heart in an acute porcine model.

    Science.gov (United States)

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

    2013-01-01

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

  14. Intratumoral coagulation by radiofrequency ablation facilitated the laparoscopic resection of giant hepatic hemangioma: a surgical technique report of two cases.

    Science.gov (United States)

    Wang, Shaohong; Gao, Jun; Yang, Mengmeng; Ke, Shan; Ding, Xuemei; Kong, Jian; Xu, Li; Sun, Wenbing

    2017-08-01

    Traditionally, open hepatic resection is the first choice of treatment for symptomatic enlarging hepatic hemangiomas, which requires a large abdominal incision and is associated with substantial recovery time and morbidity. Minimally invasive laparoscopic resection has been used recently in liver surgery for treating selected hepatic hemangiomas. However, laparoscopic liver surgery poses the significant technical challenges and high rate of conversion. Radiofrequency (RF) ablation has been proved feasible in the treatment of hepatic hemangiomas with a size range of 5.0-9.9 cm. It is controversial to treat giant hepatic hemangiomas (≥10.0 cm) by means of RF ablation, due to the low technique success rate and high incidence of ablation-related complications. We aimed to assess the safety and efficacy of combined laparoscopic resection with intratumoral RF-induced coagulation for giant hepatic hemangiomas. We treated 2 patients with giant subcapsular hepatic hemangioma (12.0 cm and 13.1 cm in diameters respectively) by laparoscopic resection following intratumoral coagulation of the tumor with RF ablation. Blood loss during resection was 100 ml (case 1) and 300ml (case 2) respectively. No blood transfusion and dialysis were needed during perioperative period. The two patients were discharged 6 days (case 1) and 12 days (case 2) after surgery without any complications, respectively. Postoperative contrast-enhanced CT follow up showed there was no residual tumor. It is feasible to treat giant subcapsular hepatic hemangioma by laparoscopic tumor resection boosted by intratumoral coagulation using RF ablation, which may open a new avenue for treating giant hemangioma.

  15. Radiofrequency ablation assisted by real-time virtual sonography for hepatocellular carcinoma inconspicuous under sonography and high-risk locations

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    Cheng-Han Lee

    2015-08-01

    Full Text Available Radiofrequency ablation (RFA is an effective and real-time targeting modality for small hepatocellular carcinomas (HCCs. However, mistargeting may occur when the target tumor is confused with cirrhotic nodules or because of the poor conspicuity of the index tumor under ultrasonography (US. Real-time virtual sonography (RVS can provide the same reconstruction computed tomography images as US images. The aim of this study is to investigate the usefulness of RVS-assisted RFA for HCCs that are inconspicuous or conspicuous under US. A total of 21 patients with 28 HCC tumors—divided into US inconspicuous and high-risk subgroup (3 tumors in 3 patients, US inconspicuous and nonhigh-risk subgroup (5 tumors in 4 patients, US conspicuous and high-risk subgroup (16 tumors in 14 patients, and US conspicuous and nonhigh-risk subgroup (4 tumors in 3 patients—underwent RVS-assisted RFA between May 2012 and June 2014 in our institution. The mean diameter of the nodules was 2.0 ± 1.1 cm. The results showed that the complete ablation rate is 87.5% (7/8 in the US undetectable group and 75% (15/20 in the US detectable group. A comparison between six tumors with incomplete ablation and 22 tumors with complete ablation showed higher alpha-fetoprotein level (mean, 1912 ng/mL vs. 112 ng/mL and larger tumor size (mean diameter, 26 mm vs. 16 mm in the incomplete ablation nodules (both p < 0.05. In conclusion, RVS-assisted RFA is useful for tumors that are difficult to detect under conventional US and may also be useful for tumors in high-risk locations because it may prevent complication induced by mistargeting.

  16. Percutaneous radiofrequency ablation of osteoid osteomas with use of real-time needle guidance for accurate needle placement: a pilot study

    NARCIS (Netherlands)

    Busser, W.M.H.; Hoogeveen, Y.L.; Veth, R.P.H.; Schreuder, H.W.B.; Balguid, A.; Renema, W.K.J.; Schultze Kool, L.J.

    2011-01-01

    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

  17. Local recurrence rates after radiofrequency ablation or resection of colorectal liver metastases. Analysis of the European Organisation for Research and Treatment of Cancer #40004 and #40983

    NARCIS (Netherlands)

    Tanis, E.; Nordlinger, B.; Mauer, M.; Sorbye, H.; van Coevorden, F.; Gruenberger, T.M.; Schlag, P.M.; Punt, C.J.A.; Ledermann, J.; Ruers, Theo J.M.

    2014-01-01

    Aim The aim of this study is to describe local tumour control after radiofrequency ablation (RFA) and surgical resection (RES) of colorectal liver metastases (CLM) in two independent European Organisations for Research and Treatment of Cancer (EORTC) studies. Background Only 10–20% of patients with

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

    NARCIS (Netherlands)

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

    2015-01-01

    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

  19. Efficacy of a novel bipolar radiofrequency ablation device on the beating heart for atrial fibrillation ablation: a long-term porcine study.

    Science.gov (United States)

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

    2010-07-01

    Over recent years, a variety of energy sources have been used to replace the traditional incisions of the Cox maze procedure for the surgical treatment of atrial fibrillation. This study evaluated the safety and efficacy of a new bipolar radiofrequency ablation device for atrial ablation in a long-term porcine model. Six pigs underwent a Cox maze IV procedure on a beating heart off cardiopulmonary bypass using the AtriCure Isolator II bipolar ablation device (AtriCure, Inc, Cincinnati, Ohio). In addition, 6 pigs underwent median sternotomy and pericardiotomy alone to serve as a control group. All animals were allowed to survive for 30 days. Each pig underwent induction of atrial fibrillation and was then humanely killed to remove the heart en bloc for histologic assessment. Magnetic resonance imaging scans were also obtained preoperatively and postoperatively to assess atrial and ventricular function, pulmonary vein anatomy, valve function, and coronary artery patency. All animals survived the operation. Electrical isolation of the left atrial appendage and the pulmonary veins was documented by pacing acutely and at 30 days in all animals. No animal that underwent the Cox maze IV procedure was able to be induced into atrial fibrillation at 30 days postoperatively, compared with all the sham animals. All 257 ablations examined were discrete, linear, and transmural, with a mean lesion width of 2.2 +/- 1.1 mm and a mean lesion depth of 5.3 +/- 3.0 mm. The AtriCure Isolator II device was able to create reliable long-term transmural lesions of the modified Cox maze procedure on a beating heart without cardiopulmonary bypass 100% of the time. There were no discernible effects on ventricular or valvular function. 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  20. Acoustic signal emission monitoring as a novel method to predict steam pops during radiofrequency ablation: preliminary observations.

    Science.gov (United States)

    Chik, William W B; Kosobrodov, Roman; Bhaskaran, Abhishek; Barry, Michael Anthony Tony; Nguyen, Doan Trang; Pouliopoulos, Jim; Byth, Karen; Sivagangabalan, Gopal; Thomas, Stuart P; Ross, David L; McEwan, Alistair; Kovoor, Pramesh; Thiagalingam, Aravinda

    2015-04-01

    Steam pop is an explosive rupture of cardiac tissue caused by tissue overheating above 100 °C, resulting in steam formation, predisposing to serious complications associated with radiofrequency (RF) ablations. However, there are currently no reliable techniques to predict the occurrence of steam pops. We propose the utility of acoustic signals emitted during RF ablation as a novel method to predict steam pop formation and potentially prevent serious complications. Radiofrequency generator parameters (power, impedance, and temperature) were temporally recorded during ablations performed in an in vitro bovine myocardial model. The acoustic system consisted of HTI-96-min hydrophone, microphone preamplifier, and sound card connected to a laptop computer. The hydrophone has the frequency range of 2 Hz to 30 kHz and nominal sensitivity in the range -240 to -165 dB. The sound was sampled at 96 kHz with 24-bit resolution. Output signal from the hydrophone was fed into the camera audio input to synchronize the video stream. An automated system was developed for the detection and analysis of acoustic events. Nine steam pops were observed. Three distinct sounds were identified as warning signals, each indicating rapid steam formation and its release from tissue. These sounds had a broad frequency range up to 6 kHz with several spectral peaks around 2-3 kHz. Subjectively, these warning signals were perceived as separate loud clicks, a quick succession of clicks, or continuous squeaking noise. Characteristic acoustic signals were identified preceding 80% of pops occurrence. Six cardiologists were able to identify 65% of acoustic signals accurately preceding the pop. An automated system identified the characteristic warning signals in 85% of cases. The mean time from the first acoustic signal to pop occurrence was 46 ± 20 seconds. The automated system had 72.7% sensitivity and 88.9% specificity for predicting pops. Easily identifiable characteristic acoustic emissions

  1. Bipolar radiofrequency ablation using internally cooled electrodes in ex vivo bovine liver: prediction of coagulation volume from applied energy.

    Science.gov (United States)

    Clasen, Stephan; Schmidt, Diethard; Dietz, Klaus; Boss, Andreas; Kröber, Stefan M; Schraml, Christina; Fritz, Jan; Claussen, Claus D; Pereira, Philippe L

    2007-01-01

    We sought to evaluate the relationship between parameters of bipolar radiofrequency (RF) ablation using internally cooled electrodes. Bipolar RF ablations (n = 24) were performed in ex vivo bovine liver using an internally cooled applicator with 2 electrodes located on the same shaft. The power-output was systematically varied (20-75 W). On the basis of our experimental data, mathematical functions were fitted and the goodness-of-fit was assessed by the parameter R. The duration to induce an increase of tissue resistance and the amount of applied energy increased with a decreased power-output. The maximum short-axis was 4.5 cm (20 W) and required an application of 64 kilojoules (kJ). The volume of coagulation can be determined as a function of the duration of energy application (R = 0.954) and the amount of applied energy (R = 0.945). The amount of applied energy and the duration of energy application can predict the volume of induced coagulation and may be useful to control internally cooled bipolar RF ablation.

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

    Energy Technology Data Exchange (ETDEWEB)

    Pai, Madhava, E-mail: madhava.pai@imperial.ac.uk [Hammersmith Hospital, Imperial College, HPB Unit, Department of Surgery (United Kingdom); Valek, Vlastimil; Tomas, Andrasina [University Hospital Brno Bohunice, Department of Radiology (Czech Republic); Doros, Attila [Semmelweis University, Radiology Unit, Department of Transplantation and Surgery (Hungary); Quaretti, Pietro [IRCCS Policlinico San Matteo, Department of Radiology (Italy); Golfieri, Rita; Mosconi, Cristina [University of Bologna, Department of Radiology, Policlinico S. Orsola-Malpighi (Italy); Habib, Nagy, E-mail: nagy.habib@imperial.ac.uk [Hammersmith Hospital, Imperial College, HPB Unit, Department of Surgery (United Kingdom)

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

    Science.gov (United States)

    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.

  4. CT-guided radiofrequency ablation of spinal osteoid osteomas with concomitant perineural and epidural irrigation for neuroprotection

    Energy Technology Data Exchange (ETDEWEB)

    Klass, Darren [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom); Norfolk and Norwich University Hospital, Radiology Academy, Cotman Centre, Norwich (United Kingdom); Marshall, Tom; Toms, Andoni [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom)

    2009-09-15

    Here we report our experience of a neuroprotective adaptation of the technique of CT-guided radiofrequency (RF) ablation of spinal osteoid osteomas. Over 9 years seven patients underwent eight CT-guided RF treatments for osteoid osteoma. CT-guided RF ablation was performed with general anaesthesia. The lesion was heated to 90 C for 2 min for two cycles by using a Cosman SMK TC-10 RF electrode. This was preceded by a bolus of room temperature sterile water (10 ml) injected through a 26G curved spinal needle into the exit foramen and adjacent epidural space for neuroprotection. The age of the patient, sex, lesion location, biopsy results and complications were recorded. All the biopsies (n = 7) demonstrated histological features of osteoid osteoma. All the procedures were technically successful. Clinical success was assessed up to 3 years post procedure. There was an 85% clinical success rate (6 of the 7 patients), with recurrence of a lesion at 6 months, necessitating a repeat procedure (successful). CT-guided percutaneous RF ablation of spinal osteoid osteoma preceded by bolus of sterile water, injected through a spinal needle into the exit foramen and adjacent epidural space for neuroprotection, is a safe and effective procedure. (orig.)

  5. Randomized trial of radiofrequency ablation versus conventional surgery for superficial venous insufficiency: if you don’t tell, they won’t know

    Directory of Open Access Journals (Sweden)

    Cynthia de Almeida Mendes

    Full Text Available OBJECTIVES: This study compared radiofrequency ablation versus conventional surgery in patients who had not undergone previous treatment for bilateral great saphenous vein insufficiency, with each patient serving as his own control. METHOD: This was a randomized controlled trial that included 18 patients and was carried out between November 2013 and May 2015. Each of the lower limbs of each patient was randomly assigned to undergo either radiofrequency ablation or conventional surgery. Clinical features (hyperpigmentation, hematoma, aesthetics, pain, skin burn, nerve injury, and thrombophlebitis were evaluated at one week, one month, and six months postoperatively. Hemodynamic assessments (presence of resection or occlusion of the great saphenous vein and recurrent reflux in the sapheno-femoral junction and in the great saphenous vein were performed at one month, six months, and 12 months postoperatively. The independent observer (a physician not involved in the original operation, patient, and duplex ultrasonographer were not made aware of the treatment done in each case. Clinicaltrials.gov: NCT02588911. RESULTS: Among the clinical variables analyzed, only the aesthetic evaluation by the physicians was significant, with radiofrequency ablation being considered better than conventional surgery (average, 0.91 points higher: standard deviation: 0.31; 95% confidence interval: -1.51, -0.30; p=0.003. However, in our study, we observed primary success rates of 80% for radiofrequency ablation and 100% for conventional surgery. CONCLUSIONS: If the physician is not required to inform the patient as to the technique being performed, the patient will not be able to identify the technique based on the signs and symptoms. Our study revealed that both techniques led to high levels of patient satisfaction, but our results favor the choice of conventional surgery over radiofrequency ablation, as patients who underwent conventional surgery had better hemodynamic

  6. Percutaneous radiofrequency ablation for hepatic tumors abutting the diaphragm: clinical assessment of the heat-sink effect of artificial ascites.

    Science.gov (United States)

    Nam, Sang Yu; Rhim, Hyunchul; Kang, Tae Wook; Lee, Min Woo; Kim, Young-Sun; Choi, Dongil; Lee, Won Jae; Park, Yulri; Chang, Ilsoo; Lim, Hyo K

    2010-02-01

    This study was designed to assess whether artificial ascites has a heat-sink effect on the ablation zone for percutaneous radiofrequency ablation (RFA) of hepatic tumors abutting the diaphragm. We retrospectively assessed 28 patients who underwent percutaneous RFA for the treatment of a single nodular hepatic tumor that abutted the diaphragm from July 2000 to December 2006. All patients underwent ultrasound-guided RFA using internally cooled electrodes. A single ablation for 12 minutes was applied using 3-cm active-tip electrodes. We divided patients into two groups on the basis of whether artificial ascites was introduced before RFA: Group A consisted of patients who received artificial ascites with a mean of 760 mL of a 5% dextrose in water solution (n = 15) and group B consisted of patients who did not receive artificial ascites (n = 13). The volume of the ablation zone was measured on CT images obtained immediately after the ablation procedure, and imaging findings were compared for both groups using the Student's t test. We also compared the local tumor progression rate between both groups using the chi-square test (mean follow-up, 37.4 months). There was no significant difference between the two patient groups with regard to age, sex, Child-Pugh class, or tumor location (p > 0.05). The tumors were significantly smaller in group A patients (mean +/- SD, 1.6 +/- 0.5 cm) than in group B patients (2.1 +/- 0.7 cm) (p = 0.019). The mean volume of the RFA zone was 31.6 +/- 11.9 cm(3) in group A patients and 30.9 +/- 11.0 cm(3) in group B patients. There was no significant difference between the groups in the ablation volume (p = 0.871). Local tumor progression was noted in four patients (26.7%) in group A and in three patients (23.1%) in group B. There was no significant difference in the local tumor progression rate between the two groups (p = 0.83). Artificial ascites did not show a heat-sink effect on the volume of the ablation zone after percutaneous RFA for the

  7. Percutaneous radiofrequency ablation for a recurrent metastasis after resection of liver metastases from an ileal clear-cell sarcoma: Long-term local tumor control

    Directory of Open Access Journals (Sweden)

    Jung Wook Seo, MD

    2017-12-01

    Full Text Available Clear-cell sarcomas (CCSs in the gastrointestinal tract are extremely rare and aggressive tumors. We present the first case of a CCS arising in the ileum and metastasizing to the liver; our patient was a 60-year-old man. After the resection of the CCS and the liver metastases, a new liver metastasis developed, which was treated via percutaneous radiofrequency ablation only. At the 5-year follow-up, the ablated region was stable without local tumor progression. Percutaneous radiofrequency ablation is a viable local treatment option for recurrent metastases from an ileal CCS if they are detected when small and at an early stage in follow-up studies.

  8. Efficacy and Safety of Strict Voltage-based Substrate Mapping and Radiofrequency Catheter Ablation in Electrical Storms—Review of Substrate-mapping Guided Ablation in Frequent Appropriate Shocks

    OpenAIRE

    Arimoto, Takanori; Tada, Hiroshi; Sekiguchi, Yukio; Koyama, Takashi; Igarashi, Miyako; Yamasaki, Hiro; Machino, Takeshi; Kuroki, Kenji; Kuga, Keisuke; Aonuma, Kazutaka

    2009-01-01

    Background: We investigated the efficacy and safety of strict voltage-based substrate mapping and radiofrequency catheter ablation (SV-substrate-map ablation) in patients with electrical storm. Methods and Results: SV-substrate-map ablation was performed in 15 patients suffering from multiple appropriate shocks (6.0 ± 3.8/day) from implantable cardioverter defibrillators (ICDs). Strict voltage criteria were defined as: non-arrhythmogenic areas, >0.6mV; low voltage areas, >0.1 to ≤0.6 mV; a...

  9. Lesion dimensions during temperature-controlled radiofrequency catheter ablation of left ventricular porcine myocardium

    DEFF Research Database (Denmark)

    Høgh Petersen, H; Chen, X; Pietersen, Adrian

    1999-01-01

    the effect of catheter-tip length, ablation site, and convective cooling on lesion dimensions. METHODS AND RESULTS: In vitro strips of porcine left ventricular myocardium during different levels of convective cooling and in vivo pig hearts at 2 or 3 left ventricular sites were ablated with 2- to 12-mm...

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

    Science.gov (United States)

    Glazer, Evan S; Curley, Steven A

    2011-10-01

    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.

  11. Alteration of laboratory findings after radiofrequency ablation of hepatocellular carcinoma: relationship to severity of the underlying liver disease and the ablation volume

    Directory of Open Access Journals (Sweden)

    Sang-Wook Shin

    2015-03-01

    Full Text Available Background/AimsTo investigate sequential changes in laboratory markers after radiofrequency ablation (RFA of hepatocellular carcinoma (HCC and the relationship of these changes to the severity of the underlying liver disease.MethodsThis retrospective analysis included 65 patients (44 males, 21 females who underwent RFA of HCC. Hematologic and biochemical markers were assessed at the pre-RFA period and 1 day, 2-3 days, and 1-2 weeks after RFA. We classified the subjects into two groups: Child-Pugh A (n=41 and Child-Pugh B (n=24. The ablative margin volume (AMV of each patient was measured. We analyzed the changes in laboratory profiles from the baseline, and investigated whether these laboratory changes were correlated with the AMV and the Child-Pugh classification.ResultsMost of the laboratory values peaked at 2-3 days after RFA. AMV was significantly correlated with changes in WBC count, hemoglobin level, and serum total bilirubin level (Pearson's correlation coefficient, 0.324-0.453; P<0.05. The alanine aminotransferase (ALT level varied significantly over time (P=0.023.ConclusionsMost of the measured laboratory markers changed from baseline, peaking at 2-3 days. The ALT level was the only parameter for which there was a significant difference after RFA between Child-Pugh A and B patients: it increased significantly more in the Child-Pugh A patients.

  12. Transepidermal retinoic acid delivery using ablative fractional radiofrequency associated with acoustic pressure ultrasound for stretch marks treatment.

    Science.gov (United States)

    Issa, Maria Cláudia Almeida; de Britto Pereira Kassuga, Luiza Erthal; Chevrand, Natalia Stroligo; do Nascimento Barbosa, Livia; Luiz, Ronir Raggio; Pantaleão, Luciana; Vilar, Enoi Guedes; Rochael, Mayra Carrijo

    2013-02-01

    Striae distensae (SD) treatment still remains a therapeutic challenge to dermatologists. Ablative fractional laser and radiofrequency (RF) enhance skin-drug permeability for SD treatment. To clinically evaluate the efficacy and safety as well as patient's satisfaction in relation to a method using ablative fractional RF associated with retinoic acid 0.05% cream and an acoustic pressure wave ultrasound (US) in patients with alba-type SD on the breast. Eight patients with alba-type SD on the breast were treated with three step procedure: (1) fractional ablative RF for skin perforation; (2) topical application of retinoic acid 0.05% on the perforated skin; and (3) US was applied to enhance the retinoic acid penetration into the skin. Other eight patients with alba-type SD on the abdominal area were submitted to RF treatment isolated without retinoic acid or US. Three of them were submitted to skin biopsies. Three patients with SD on the breast area improved from "severe" to "moderate;" two patients improved from "severe" to "mild;" two patients from "moderate" to "mild;" one patient from "marked" to "mild." Clinical assessment demonstrated significant improvement in the appearance of SD in all patients treated with RF associated with retinoic acid 0.05% cream and US (P = 0.008), with low incidence of side effects and high level of patient's satisfaction. Among the patients treated only with RF, two patients improved from "severe" to "marked;" one patient from "marked" to "moderate;" and one patient improved from "marked" to "mild." Four patients did not show any sort of improvement. Clinical assessment demonstrated no significant improvement in the appearance of SD treated with RF isolated with low incidence of side effects, but low-level of patient's satisfaction. Ablative fractional RF and acoustic pressure US associated with retinoic acid 0.05% cream is safe and effective for alba-type SD treatment. Copyright © 2012 Wiley Periodicals, Inc.

  13. Cardiac CT assessment of tissue thickness at the ostium of the left atrial appendage predicts acute success of radiofrequency ablation.

    Science.gov (United States)

    Whitaker, John; Panikker, Sandeep; Fastl, Thomas; Corrado, Cesare; Virmani, Renu; Kutys, Robert; Lim, Eric; O'Nei, Markll; Nicol, Ed; Niederer, Steven; Wong, Tom

    2017-09-21

    Tissue thickness at the site of ablation is a determinant of lesion transmurality. We reported the feasibility, safety and efficacy of long-standing persistent atrial fibrillation (PsAF) ablation, incorporating deliberate LAA isolation and occlusion and identified systematic differences in ostial LAA tissue thickness in a matched cohort of cadaveric specimens. Pre-procedural CCT scans were acquired from 22 patients undergoing LAA isolation and subsequent occlusion. Using a novel CCT wall thickness algorithm, LAA ostial wall thickness was assessed in vivo, compared with measurements from the cadaveric specimens and analysed for differences between regions that demonstrated acute electrical reconnection and those that did not. Mean tissue thickness calculated for each LAA ostial quadrant was 2.1(+/-0.6)mm (anterior quadrant), 1.9(+/-0.4)mm (superior quadrant), 1.5(+/-0.4)mm (posterior quadrant) and 1.8(+/-0.7)mm (inferior quadrant). Tissue was significantly thicker in the anterior (p = 0.004) and superior quadrants (p = 0.014) than the posterior quadrant. Higher thickness measurements were recorded from quadrants demonstrated to be thicker from histology. Tissue was significantly thicker in regions that demonstrated acute electrical reconnection (1.9(+/-0.6)mm) when compared with those that did not (1.6(+/-0.5)mm) (p = 0.008). CCT imaging may be used to detect differences in wall thickness at different atrial locations and success of LAA ablation may be affected by local tissue thickness. Atrial wall thickness may need to be considered as a metric to guide titration of radiofrequency (RF) energy for safe and successful ablation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. A novel approach in the use of radiofrequency catheter ablation of septal hypertrophy in hypertrophic obstructive cardiomyopathy.

    Science.gov (United States)

    Shelke, Abhijeet B; Menon, Rajeev; Kapadiya, Anuj; Yalagudri, Sachin; Saggu, Daljeet; Nair, Sandeep; Narasimhan, C

    Alcohol septal ablation (ASA) is a therapeutic alternative to surgical myectomy in patients with hypertrophic obstructive cardiomyopathy (HOCM). However, the anatomical variability of the septal branch, risk of complete heart block, and late onset ventricular arrhythmias are limitations to its therapeutic usage. There is recent interest in the use of radiofrequency catheter ablation (RFCA) as a therapeutic option in HOCM. We aimed to assess the safety and efficacy of RFCA in the treatment of symptomatic HOCM. Seven patients with symptomatic HOCM (mean age 43.7±15.6 years, five males), and significant left ventricular outflow tract (LVOT) gradient despite optimal drug therapy, underwent ablation of the hypertrophied interventricular septum. These patients had unfavorable anatomy for ASA. Ablation was performed under 3D electro-anatomical system guidance using an open irrigated tip catheter. The region of maximal LV septal bulge as seen on intracardiac echocardiography was targeted. Patients were followed up at 1, 6, and 12 months post-procedure. The mean baseline LVOT gradient by Doppler echocardiography was 81±14.8mm of Hg which reduced to 48.5±22.6 (p=0.0004), 49.8±19.3 (p=0.0004), and 42.8±26.1mm of Hg (p=0.05) at 1, 6, and 12 months respectively. Symptoms improved at least by one NYHA class in all but one patient. One patient developed transient pulmonary edema post-RFA. There were no other complications. RFCA of the hypertrophied septum causes sustained reduction in the LVOT gradient and symptomatic improvement among patients with HOCM. Electroanatomical mapping helps to perform the procedure safely. Copyright © 2016 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  15. Analytical validation of COMSOL Multiphysics for theoretical models of Radiofrequency ablation including the Hyperbolic Bioheat transfer equation.

    Science.gov (United States)

    Rivera, Maria J; López Molina, Juan A; Trujillo, Macarena; Romero-Garcia, Vicente; Berjano, Enrique J

    2010-01-01

    In this paper we outline our main findings about the differences between the use of the Bioheat Equation and the Hyperbolic Bioheat Equation in theoretical models for Radiofrequency (RF) ablation. At the moment, we have been working on the analytical approach to solve both equations, but more recently, we have considered numerical models based on the Finite Element Method (FEM). As a first step to use FEM, we conducted a comparative study between the temperature profiles obtained from the analytical solutions and those obtained from FEM. Regarding the differences between both methods, we obtain agreement in less than 5% of relative differences. Then FEM is a good alternative to model heating of biological tissues using BE and HBE in, for example, more complex and realistic geometries.

  16. Ultrasound-guided alcohol neurolysis and radiofrequency ablation of painful stump neuroma: effective treatments for post-amputation pain

    Directory of Open Access Journals (Sweden)

    Zhang X

    2017-02-01

    Full Text Available Xin Zhang, Yongming Xu, Jin Zhou, Shaofeng Pu, Yingying Lv, Yueping Chen, Dongping Du Pain Management Center, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China Background: Post-amputation pain (PAP is highly prevalent after limb amputation, and stump neuromas play a key role in the generation of the pain. Presently, PAP refractory to medical management is frequently treated with minimally invasive procedures guided by ultrasound, such as alcohol neurolysis and radiofrequency ablation (RFA.Objective: To record the immediate and long-term efficacy of alcohol neurolysis and RFA. We first used alcohol neurolysis and then, when necessary, we performed RFA on PAP patients.Study design: Prospective case series.Setting: Pain management center.Methods: Thirteen subjects were treated with ultrasound-guided procedures.Results: All patients were treated with neurolysis using alcohol solutions guided by ultrasound. Seven (54% of 13 subjects achieved pain relief after 1–3 alcohol injection treatments. The remaining 6 subjects obtained pain relief after receiving 2 administrations of ultrasound-guided RFA. After a 6-month follow-up evaluation period, pain quantities were also assessed. Both stump pain (including intermittent sharp pain and continuous burning pain and phantom pain were relieved. The frequency of intermittent sharp pain was decreased, and no complications were noted during the observation.Conclusion: The use of ultrasound guidance for alcohol injection and RFA of painful stump neuromas is a simple, radiation-free, safe, and effective procedure that provides sustained pain relief in PAP patients. In this case series, RFA was found to be an effective alternative to alcohol injection. Keywords: post-amputation pain, neuroma, ultrasound-guided, alcohol neurolysis, radiofrequency ablation

  17. Successful performance of Cox-Maze procedure on beating heart using bipolar radiofrequency ablation: a feasibility study in animals.

    Science.gov (United States)

    Gaynor, Sydney L; Ishii, Yosuke; Diodato, Michael D; Prasad, Sunil M; Barnett, Kara M; Damiano, Nicholas R; Byrd, Gregory D; Wickline, Samuel A; Schuessler, Richard B; Damiano, Ralph J

    2004-11-01

    The Cox-Maze procedure is the gold standard for the surgical treatment of atrial fibrillation with proven long-term efficacy. However, its application has been limited by its complexity and significant morbidity. The purpose of this study was to test the feasibility and safety of performing the Cox-Maze procedure using bipolar radiofrequency ablation on the beating heart without cardiopulmonary bypass. After median sternotomy, 6 Hanford mini-pigs underwent a modified Cox-Maze procedure using bipolar radiofrequency energy. The animals survived for 30 days. Atrial function, coronary artery, pulmonary vein anatomy, and valve function were assessed by magnetic resonance imaging. At reoperation, pacing documented electrical isolation of the pulmonary veins. Induction of atrial fibrillation was attempted by burst pacing with cholinergic stimulation. Histologic assessment was performed after sacrifice. There were no perioperative mortalities or neurologic events. At 30 days, atrial fibrillation was unable to be induced, and pulmonary vein isolation was confirmed by pacing. Magnetic resonance imaging assessment revealed no coronary artery or pulmonary vein stenoses. Although atrial ejection fraction decreased slightly from 0.344 +/- 0.0114 to 0.300 +/- 0.055 (p = 0.18), atrial contractility was preserved in every animal. Histologic assessment showed all lesions to be transmural, and there were no significant stenoses of the coronary vessels or injuries to the valves. Virtually all of the lesions of the Cox-Maze procedure can be performed without cardiopulmonary bypass using bipolar radiofrequency energy. There were no late stenoses of the pulmonary veins. Clinical trials of this new technology on the beating heart are warranted.

  18. Effect of heat sink on the recurrence of small malignant hepatic tumors after radiofrequency ablation

    Directory of Open Access Journals (Sweden)

    Zheng-Yu Lin

    2016-01-01

    Conclusions: The curative effect of MRI-guided RFA is better than those of US- and CT-guided ablation. The heat sink effect is an important factor affecting recurrence of hepatic malignant tumors after RFA.

  19. Percutaneous radiofrequency ablation guided by contrast-enhanced ultrasound in treatment of metastatic hepatocellular carcinoma after liver transplantation.

    Science.gov (United States)

    Dai, Xin; Zhao, Hong-Qiang; Liu, Run-Hao; Xu, Chang-Tao; Zheng, Fang; Yu, Li-Bao; Li, Wei-Min

    2012-01-01

    This study evaluated the advantages and applications of contrast-enhanced ultrasound (CEUS)-supported percutaneous radiofrequency ablation (RFA) in the treatment of metastatic hepatocellular carcinoma after liver transplantation, based on clinical details. CEUS-supported percutaneous RFA was adopted to treat 12 patients with hepatic metastatic carcinomas after liver transplantation. The diameters of the metastatic carcinomas varied from 1 cm to 5 cm, and the foci were discovered after 3 months to 12 months. Each focus was diagnosed and localised by CEUS for RFA once or twice. Curative effects were evaluated by CEUS or contrast-enhanced CT after the treatment. The re-examination results at 2 weeks post-treatment showed that the foci of 11 patients were ablated completely, whereas one patient with the largest focus required retreatment by RFA because of a partial residue. No local recurrence was found one month later in the re-examination. CEUS-supported percutaneous RFA in the treatment of hepatic metastatic carcinoma after liver transplantation has the advantages of accurate localisation, good efficacy, easy operation, and minimal invasion without any complications. Therefore, it can be recommended as the preferred therapy for hepatic metastatic carcinoma after liver transplantation.

  20. Osteoid osteoma and osteoid osteoma-mimicking lesions: biopsy findings, distinctive MDCT features and treatment by radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Becce, Fabio [Centre Hospitalier Universitaire Vaudois, Department of Diagnostic and Interventional Radiology, Lausanne (Switzerland); Universite Paris Descartes, Department of Radiology B, Hopital Cochin, AP-HP, Paris (France); Theumann, Nicolas [Centre Hospitalier Universitaire Vaudois, Department of Diagnostic and Interventional Radiology, Lausanne (Switzerland); Rochette, Antoine; Campagna, Raphael; Drape, Jean-Luc; Feydy, Antoine [Universite Paris Descartes, Department of Radiology B, Hopital Cochin, AP-HP, Paris (France); Larousserie, Frederique [Universite Paris Descartes, Department of Anatomic Pathology, Hopital Cochin, AP-HP, Paris (France); Cherix, Stephane; Mouhsine, Elyazid [Centre Hospitalier Universitaire Vaudois, Department of Orthopaedic and Traumatologic Surgery, Lausanne (Switzerland); Guillou, Louis [University Institute of Pathology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Anract, Philippe [Universite Paris Descartes, Department of Orthopaedic Surgery, Hopital Cochin, AP-HP, Paris (France)

    2010-10-15

    To report the biopsy findings of osteoid osteoma (OO) and OO-mimicking lesions, assess their distinctive multidetector computed tomography (MDCT) features and evaluate treatment by radiofrequency ablation (RFA). In this multicentric retrospective study, 80 patients (54 male, 26 female, mean age 24.1 years, range 5-48) with presumed (clinical and MDCT features) OO were treated by percutaneous RFA between May 2002 and June 2009. Per-procedural biopsies were always performed. The following MDCT features were assessed: skeletal distribution and location within the bone, size, central calcification, surrounding osteosclerosis and periosteal reaction. Clinical success of RFA was evaluated. Histopathological diagnoses were: 54 inconclusive biopsies, 16 OO, 10 OO-mimicking lesions (5 chronic osteomyelitis, 3 chondroblastoma, 1 eosinophilic granuloma, 1 fibrous dysplasia). OO-mimicking lesions were significantly greater in size (p = 0.001) and presented non-significant trends towards medullary location (p = 0.246), moderate surrounding osteosclerosis (p = 0.189) and less periosteal reaction (p = 0.197), compared with OO. Primary success for ablation of OO-mimicking lesions was 100% at 1 month, 85.7% at 6 and 12 months, and 66.7% at 24 months. Secondary success was 100%. Larger size, medullary location, less surrounding osteosclerosis and periosteal reaction on MDCT may help differentiate OO-mimicking lesions from OO. OO-mimicking lesions are safely and successfully treated by RFA. (orig.)

  1. Force-Sensing Catheters During Pediatric Radiofrequency Ablation: The FEDERATION Study.

    Science.gov (United States)

    Dalal, Aarti S; Nguyen, Hoang H; Bowman, Tammy; Van Hare, George F; Avari Silva, Jennifer N

    2017-05-17

    Based on data from studies of atrial fibrillation ablations, optimal parameters for the TactiCath (TC; St. Jude Medical, Inc) force-sensing ablation catheter are a contact force of 20 g and a force-time integral of 400 g·s for the creation of transmural lesions. We aimed to evaluate TC in pediatric and congenital heart disease patients undergoing ablation. Comprehensive chart and case reviews were performed from June 2015 to March 2016. Of the 102 patients undergoing electrophysiology study plus ablation, 58 (57%) underwent ablation initially with a force-sensing catheter. Patients had an average age of 14 (2.4-23) years and weight of 58 (18-195) kg with 15 patients having abnormal cardiac anatomy. Electrophysiology diagnoses for the +TC group included 30 accessory pathway-mediated tachycardia, 24 atrioventricular nodal reentrant tachycardia, and 7 other. Baseline generator settings included a power of 20 W, temperature of 40°, and 6 cc/min flow during lesion creation with 11 patients (19%) having alterations to parameters. Seventeen patients (30%) converted to an alternate ablation source. A total of 516 lesions were performed using the TC with a median contact force of 6 g, force-time integral of 149 g·s, and lesion size index of 3.3. Median-term follow-up demonstrated 5 (10%) recurrences with no acute or median-term complications. TactiCath can be effectively employed in the treatment of pediatric patients with congenital heart disease with lower forces than previously described in the atrial fibrillation literature. Patients with atrioventricular nodal reentrant tachycardia or atrioventricular reciprocating tachycardia may not require transmural lesions and the TC may provide surrogate markers for success during slow pathway ablation. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  2. Third Prize: Comparison of radical nephrectomy, laparoscopic microwave thermotherapy, cryotherapy, and radiofrequency ablation for destruction of experimental VX-2 renal tumors in rabbits.

    Science.gov (United States)

    Eichel, Louis; Kim, Issac Y; Uribe, Carlos; Khonsari, Sephir; Basillote, Jay; Steward, Earl; Coad, James; Bischof, John; Rudie, Eric; Kluge, Stan; McDougall, Elspeth M; Clayman, Ralph V

    2005-11-01

    Currently available minimally invasive renal tumor-ablation procedures include cryotherapy, radiofrequency ablation, and microwave thermotherapy. In this study, we investigated the ability of these three approaches to destroy experimental renal tumors in rabbits. The mechanism of potential tumor metastasis was also explored. The VX-2 tumor line is an aggressive rabbit epidermoid tumor with a high metastatic potential. An initial experiment comparing cooled-tip microwave thermotherapy with cryotherapy and radical nephrectomy for treatment of small VX-2 tumors revealed that all microwave-treated rabbits had local recurrence and that several also had diffuse intraperitoneal carcinomatosis. In view of these results, a second experiment was performed in which 45 New Zealand White rabbits were implanted laparoscopically with VX-2 xenografts underneath the kidney capsule and divided into five groups of 9 each. The test groups were microwave thermotherapy with a 3.5-mm cooled-tip probe, microwave thermotherapy with a 3.5-mm noncooled- tip probe, radiofrequency ablation with a 1.5-mm cooled-tip probe, radiofrequency ablation with a 1.5- mm non-cooled tip probe, and cryotherapy with a 2.3-mm cryoprobe. The control groups were five rabbits that were not treated, five rabbits with tumors that had the tumor pierced with a probe but were untreated, and five rabbits that underwent nephrectomy after piercing of the tumor. Treatment was initiated 5 days after tumor implantation. One month later, all animals were euthanized and autopsied. At 5 days after tumor implantation, laparoscopic inspection revealed no visible peritoneal metastases. At 1 month, in the cooled and non-cooled microwave-thermotherapy groups, carcinomatosis occurred in five and six of nine animals, respectively. In comparison, carcinomatosis was detected in two of nine animals in the cryotherapy group at autopsy. With respect to cooled and non-cooled radiofrequency ablation, carcinomatosis was observed in four of

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

    Science.gov (United States)

    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.

  4. Overcoming the heat-sink phenomenon: successful radiofrequency thermal ablation of liver tumors in contact with blood vessels.

    Science.gov (United States)

    Thanos, Loukas; Mylona, Sophia; Galani, Panagiota; Pomoni, Maria; Pomoni, Anastasia; Koskinas, Ioannis

    2008-03-01

    To evaluate the efficacy and safety of computed tomography (CT)-guided radiofrequency thermal ablation (RFA) of liver tumors (hepatocellular carcinoma and liver metastases) > 3 mm in diameter that were in contact with blood vessels. During a 3-year period RFA was performed in 28 patients (age range, 36-83 years; male/female ratio, 17:11) with liver tumors (primary and metastatic) that were in contact with blood vessels > 3 mm in diameter. Tumor diameter ranged from 1.7 to 5.1 cm. To evaluate the immediate response, dual-phase dynamic CT images were obtained after intravenous contrast material administration. Imaging follow-up was at 1, 3, 6, and 12 months post-RFA, and every year thereafter. All of 28 patients were treated with a total of 36 sessions. In 22 (79%) of the patients, complete ablation of the tumor was achieved. The remaining 6 (21%) patients showed irregular peripheral enhancement and underwent a second session. At 1-year follow-up 2 of the tumors showed a recurrent lesion and a new ablation was performed. The local tumor progression rate at 1-year follow-up was 8.7% and disease-free survival was achieved in 82.1% of the patients. Complications occurred in 4 patients (14.3%); 2 patients presented with a small sub-capsular hematoma, and 2 patients had a partial liver infarction. RFA is a safe and effective method, even with high-risk tumors adjacent to large blood vessels, which can lead to good results with minimal complications and a low rate of tumor progression.

  5. Clinical study of ultrasound-guided percutaneous radiofrequency ablation for primary hepatic carcinoma adjacent to the diaphragm

    Directory of Open Access Journals (Sweden)

    LI Meng

    2015-04-01

    Full Text Available ObjectiveTo investigate the safety and efficacy of ultrasound (US-guided percutaneous radiofrequency ablation (RFA for primary hepatic carcinoma adjacent to the diaphragm. MethodsThis study included 277 patients with 362 lesions of primary hepatic carcinoma managed with US-guided percutaneous RFA in 302 Hospital of PLA from January 2011 to October 2014. Sixty-six patients with 71 hepatocellular carcinomas (HCCs located less than 5 mm from the diaphragm were in study group, and 95 patients with 114 HCCs located more than 10 mm from the hepatic surface were in control group. The patients′ symptoms and complications were observed after the therapy. The complete ablation rate, local tumor progression rate, and complication rate were compared between the two groups. Comparison of continuous data between the two groups was made by independent-samples t test, while comparison of categorical data was made by chi-square test. ResultsAt one month after operation, 65 (91.5% of 71 tumors in the study group and 107 (93.9% of 114 tumors in the control group achieved complete ablation, according to contrast-enhanced CT and MRI, and there was no significant difference between the two groups (χ2=0.36, P=0.55. The postoperative follow-up showed that the local tumor progression rates in the study group and control group were 16.9% and 13.2%, respectively, without significant difference between the two groups (χ2=0.49, P=0.48. In the study group, 22 patients developed adverse reactions, versus 37 patients in the control group (χ2=2.60, P=0.11. ConclusionUS-guided percutaneous RFA is a safe and effective means for the treatment of primary hepatic carcinoma adjacent to the diaphragm.

  6. Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia: Success Rates and Complications during 14 Years of Experience

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    Mansour Moghaddam

    2010-05-01

    Full Text Available Background: Radiofrequency catheter ablation (RFCA has been introduced as the treatment of choice for supraventricular tachycardia. The aim of this study was to evaluate the success rate as well as procedural and in-hospital complications of RFCA for the treatment of atrioventricular nodal reentrant tachycardia (AVNRT.Methods: Between March 1995 and February 2009, 544 patients (75.9% female, age: 48.89 ± 13.19 years underwent 548 RFCAs for AVNRT in two large university hospitals. Echocardiography was performed for all the patients before and after the procedure. Electrocardiograms were recorded on digital multichannel systems (EP-Med or Bard EP system. Anticoagulation was initiated during the procedure.Results: From the 548 patients, 36 had associated arrhythmias, atrial flutter (4%, atrial fibrillation (0.7%, concurrent atrial fibrillation and atrial flutter (0.7%, and concealed atrioventricular pathway (0.4%. The overall success rate was 99.6%. There were 21 (3.9% transient III-degree AV blocks (up to a few seconds and 4 (0.7% prolonged II- or III-degree AV blocks, 2 (0.25% of which required permanent pacemaker insertion, 3(0.5% deep vein thrombosis, and one (0.2% arteriovenous fistula following the procedure. No difference was observed in the echocardiography parameters before and after the ablation.Conclusion: RFCA had a high success rate. The complication rate was generally low and in the above-mentioned centers it was similar to those in other large centers worldwide. Echocardiography showed no difference before and after the ablation. The results from this study showed that the risk of permanent II or III-degree AV block in patients undergoing RFCA was low and deep vein thrombosis was the second important complication. There was no risk of life-threatening complications.

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

    Science.gov (United States)

    Yan, Shengjie; Wu, Xiaomei; Wang, Weiqi

    2016-05-01

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

  8. High-Resolution Infrared Thermography of Esophageal Temperature During Radiofrequency Ablation of Atrial Fibrillation.

    Science.gov (United States)

    Daly, Matthew G; Melton, Iain; Roper, Graham; Lim, Gary; Crozier, Ian G

    2018-02-01

    Catheter ablation for atrial fibrillation has potential to cause esophageal thermal injury. Esophageal temperature monitoring during ablation is commonly used; however, it has not eliminated thermal injuries, possibly because conventional sensors have poor spatial sampling and response characteristics. To enhance understanding of temperature dynamics that may underlie esophageal injury, we tested a high-resolution, intrabody, infrared thermography catheter to continuously image esophageal temperatures during ablation. Atrial fibrillation ablation patients were instrumented with a flexible, 9F infrared temperature catheter inserted nasally (n=8) or orally (n=8) into the esophagus adjacent to the left atrium. Ablation was performed while the infrared catheter continuously recorded surface temperatures from 7680 points per second circumferentially over a 6-cm length of esophagus. Physicians were blinded to temperature data. Endoscopy was performed within 24 hours to document esophageal injury. Thermal imaging showed that most patients (10/16) experienced ≥1 events where peak esophageal temperature was >40°C. Three patients experienced temperatures >50°C; and 1 experienced >60°C. Analysis of temperature data for each subject's maximum thermal event revealed high gradients (2.3±1.4°C/mm) and rates of change (1.5±1.3°C/s) with an average length of esophageal involvement of 11.0±5.4 mm. Endoscopy identified 3 distinct thermal lesions, all in patients with temperatures >50°C; all resolved within 2 weeks. Infrared thermography provided dynamic, high-resolution mapping of esophageal temperatures during cardiac ablation. Esophageal thermal injury occurred with temperatures >50°C and was associated with large spatiotemporal gradients. Additional studies are warranted to determine the relationships between thermal parameters and esophageal injury. © 2018 American Heart Association, Inc.

  9. Radiofrequency tissue ablation with cooled-tip electrodes:an experimental study in a bovine liver model on variables influencing lesion size

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hyun Young [Eulgy Univ. Hospital, Seoul (Korea, Republic of); Lee, Jeong Min; Kim, Chong Soo [Chonbuk National Univ. Hospital, Chonju (Korea, Republic of)

    2001-03-01

    The purpose of this study was to determine the influence of various factors on the extent of thermal coagulation necrosis after radiofrequency (RF) tissue ablation using a cooled-tip electrode in bovine liver. RF ablation was induced by a monopolar 500 KHz-RF generator (CC-1; Radionics, Burlington, Mass., U.S.A.) and an 18-G cooled-tip with single or clustered electrodes. The ablation protocol involved a combination of varying current, ablation time, power output, gradual or abrupt increase of this out-put, and pulsed radiofrequency techniques. The maximum diameter of all thermal lesions which showed a color change was measured perpendicular to the electrode axis by two observers who reached their decisions by consensus. Twenty representative lesions were pathologically examined. With increasing current lesion diameter also increased, but above 1500 mA no further increase was induced. Extending the ablation time to 9 minutes for a single electrode and 15 minutes for a clustered electrode increased lesion diameter until a steady state was reached. Higher power levels caused larger lesions, but above 100 W no increase was observed. Ample exposure time coupled with a stepwise increase in power level induced a lesion larger than that resulting from an abrupt increase. Continuous pulsed RF with a high current led to increased coagulation necrosis diameter. These experimental findings may be useful thermotherapy. The data suggest that all involved factors significantly affect lesion size:if the factors are better understood, cancer thermotherapy can be better controlled.

  10. Simultaneous (18)F-FDOPA PET/CT-guided biopsy and radiofrequency ablation of recurrent neuroendocrine hepatic metastasis: further step toward a theranostic approach.

    Science.gov (United States)

    Imperiale, Alessio; Garnon, Julien; Bachellier, Philippe; Gangi, Afshin; Namer, Izzie Jacques

    2015-06-01

    PET/CT-guided biopsy may be useful to confirm the metabolic findings when conventional imaging fails to show morphological abnormalities. Herein, we report the results of simultaneous F-FDOPA (fluorodihydroxyphenylalanine) PET/CT-guided biopsy and RFA (radiofrequency ablation) in 1 patient with hepatic metastatic evolution of a well-differentiated ileal neuroendocrine tumor. Beyond FDG, FDOPA could be successfully recommended in patients with neuroendocrine tumor for planning PET/CT-guided diagnostic biopsy, ablative treatment, and immediate efficacy assessment in a 1-step examination.

  11. Ruptured common femoral vein pseudoaneurysm from a common femoral arteriovenous fistula presenting as lower extremity steal after radiofrequency ablation of the great saphenous vein.

    Science.gov (United States)

    Brumberg, Robert Scott; Davis, Cassie

    2017-07-01

    Radiofrequency ablation of the superficial venous systems has become one of the mainstays of minimally invasive approaches to varicose veins and chronic venous insufficiency. These procedures have high rates of success with scarce complications. This case report highlights a patient with a common femoral arteriovenous fistula presenting with lower extremity steal after radiofrequency ablation treatment of the great saphenous vein. During operative repair of the arteriovenous fistula, a pseudoaneurysm of the common femoral vein ruptured. We review the current literature and highlight the importance of expanding the scope of complications that can occur from seemingly straightforward minimally invasive venous procedures. Informed consent was obtained for publication of this report. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. 23 Lung Metastases Treated by Radiofrequency Ablation Over 10 Years in a Single Patient: Successful Oncological Outcome of a Metastatic Cancer Without Altered Respiratory Function

    Energy Technology Data Exchange (ETDEWEB)

    Crombé, Amandine, E-mail: amandine.crombe@ens-lyon.fr; Buy, Xavier [Institut Bergonié, Department of Radiology (France); Godbert, Yann [Institut Bergonié, Department of Nuclear Medicine (France); Alberti, Nicolas [Centre Hospitalier Alpes-Léman, Department of Radiology (France); Kind, Michèle [Institut Bergonié, Department of Radiology (France); Bonichon, Françoise [Institut Bergonié, Department of Nuclear Medicine (France); Palussière, Jean [Institut Bergonié, Department of Radiology (France)

    2016-12-15

    An 82-year-old man, who was diagnosed in 2002 with an oncocytic (Hürthle cell) thyroid carcinoma, was initially treated by local surgery and was refractory to radioiodine treatment. The patient had successive secondary recurrences from 2006 onwards. Metastases were suspected due to an elevation of thyroglobulin in serum. Hypermetabolic nodules were targeted using FDG PET as well as CT-guided radiofrequency ablations. Thyroglobulin levels decreased following each procedure. 10 years later, tolerance and efficacy are excellent; 23 lung metastases have been treated during 11 sessions without current relapse. Respiratory function and quality of life are not altered. This report illustrates how radiofrequency ablation can be efficiently integrated into the long-term management of poorly aggressive oligometastatic cancer, in combination with other local and/or systemic therapies.

  13. Radiofrequency ablation of liver metastases-software-assisted evaluation of the ablation zone in MDCT: tumor-free follow-up versus local recurrent disease.

    Science.gov (United States)

    Keil, Sebastian; Bruners, Philipp; Schiffl, Katharina; Sedlmair, Martin; Mühlenbruch, Georg; Günther, Rolf W; Das, Marco; Mahnken, Andreas H

    2010-04-01

    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 + or - 10.3 years) with 30 metastases stayed tumor-free (group 1), while the other group (n = 16 with 24 metastases; 62.0 + or - 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(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 free and local-recurrent ablation zones with respect to the corresponding size parameters. A new parameter (lnQ1//28/0(volume/RECIST/WHO/attenuation)) was introduced, which appears to be of prognostic value at early follow-up CT.

  14. In vitro artefact assessment of a new MR-compatible microwave antenna and a standard MR-compatible radiofrequency