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Sample records for endovenous radiofrequency ablation

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

    PubMed

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

    2014-03-01

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

  2. Postoperative Venous Thromboembolism in Patients Undergoing Endovenous Laser and Radiofrequency Ablation of the Saphenous Vein

    PubMed Central

    Hirokawa, Masayuki; Yamamoto, Takashi

    2016-01-01

    Objective: Endovenous laser ablation (EVLA) and radiofrequency ablation (RFA) are safe and effective treatments for varicose veins caused by saphenous reflux. Deep venous thrombosis (DVT) and endovenous heat-induced thrombosis (EHIT) are known complications of these procedures. The purpose of this article is to investigate the incidence of postoperative DVT and EHIT in patients undergoing EVLA and RFA. Methods: The patients were assessed by clinical examination and venous duplex ultrasonography before operation and at 24–72 hours, 1 month, and 1 year follow-up after operation. Endovenous ablation (EVA) had been treated for 1026 limbs (835 patients) using an RFA; 1174 limbs (954 patients) using a 1470-nm wavelength diode laser with radial two-ring fiber (1470R); and 6118 limbs (5513 patients) using a 980-nm wavelength diode laser with bare-tip fiber (980B). Results: DVT was detected in 3 legs (0.3%) of RFA, 5 legs (0.4%) of 1470R, and 27 legs (0.4%) of 980B. One patient in three symptomatic DVT treated with 980B developed asymptomatic pulmonary embolus. In all, 31 of the 35 DVTs were confined to the calf veins. The incidence of EHIT classes 2 and 3 was 2.7% following RFA procedure, 6.7% after 1470R, and 7.5% after 980B. Conclusion: The incidence of EHIT following EVA was low, especially the RFA procedure. EHIT resolves within 2–4 weeks in most patients. DVT rates after EVA were compared with those published for saphenous vein stripping. (This is a translation of J Jpn Coll Angiol 2015; 55: 153–161.) PMID:28018495

  3. Radiofrequency Ablation of Liver Tumors

    MedlinePlus

    ... Site Index A-Z Radiofrequency Ablation (RFA) of Liver Tumors Radiofrequency ablation (RFA) is a treatment that ... of Liver Tumors? What is Radiofrequency Ablation of Liver Tumors? Radiofrequency ablation, sometimes referred to as RFA, ...

  4. Radiofrequency Ablation of Cancer

    SciTech Connect

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

    2004-09-15

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

  5. Positioning for Endovenous Laser Ablation: Comparative Study with Thigh Stripping

    PubMed Central

    Masaki, Hisao; Yunoki, Yasuhiro; Watanabe, Yoshiko; Furukawa, Hiroshi; Yamasawa, Takahiko; Takiuchi, Hiroki; Honda, Takeshi; Kuwada, Noriaki; Kojima, Kenji; Tanemoto, Kazuo

    2016-01-01

    We performed a comparative study of surgical outcomes and venous functions between endovenous laser ablation with a 980-nm diode laser (EV group) and thigh stripping (ST group). There were no severe complications and initial success rates were 100% in both groups. In the EV group, preoperative symptoms improved in 94.3% of cases, the venous occlusion rate was 98%, and endovenous heat induced thrombosis had occurred in 11.9% (Class 3: 0.7%) at 12 months after the operation. Although comparative study of postoperative venous function by air plethysmography showed significant improvement in both groups, there was less recovery of postoperative venous function in the EV than in the ST group. (This article is a translation of J Jpn Coll Angiol 2015; 55: 13–20.) PMID:27738455

  6. Outcome of Endovenous Laser Ablation of Varicose Veins

    PubMed Central

    Rustempasic, Nedzad; Cvorak, Alemko; Agincic, Alija

    2014-01-01

    ABSTRACT Introduction: In Bosnia and Herzegovina according to available data, treatment of incompetent superficial lower extremity varicose veins by endovenous laser ablation (EVLA) has been introduced two years ago and so far no paper has been published regarding results of EVLA treatment of patients from our country. We wanted to present our results with EVLA treatment. Aim of study: to evaluate and compare primary posttreatment outcomes of endovenous laser ablation (EVLA) with classical surgical method of varicose vein treatment. Patients and methods: The study was clinical and prospective. It was carried out at Clinic for vascular surgery in Sarajevo where fifty-eight (58) patients received surgical treatment for varicose veins and in Aesthetic Surgery Center “Nasa mala klinika” in Sarajevo were sixty-one (61) patients with varicose veins were treated by endovenous laser ablation. Total 119 patients (limbs) with pathologic reflux only in great saphenous vein were evaluated between 1st of January 2013 and 31st of April 2014. Following primary outcome endpoints were evaluated smean day of return to normal everyday activities, patient subjective quantification of pain during first seven days after intervention, incidence of deep venous thrombosis (DVT), incidence of wound bleeding requiring surgical intervention, incidence of peri-saphenous vein hematoma and infection rate. Results: Mean of return to normal activities (expressed in days after intervention); EVLA vs. stripping (surgery) =1.21vs12.24, T test 13,619; p=0, 000, p<0,05. T test was used for comparing Mean value of visual pain analog scale for the first 7 days between groups, for all seven days pain was significantly higher in surgical group of patients as compared to EVLA group; p<0,05. Incidence of hematoma greater than 1% of total body surface area was significantly higher in patients receiving surgical treatment; Pearson Chi Square=23,830, p<0,05; odds ratio:10,453. Incidences of infection, deep

  7. Endovenous Laser Ablation as a Treatment for Postsurgical Recurrent Saphenous Insufficiency

    SciTech Connect

    Anchala, Praveen R.; Wickman, Christopher; Chen, Richard; Faundeen, Tonya; Pearce, William; Narducy, Lisa; Resnick, Scott A.

    2010-10-15

    The purpose of this study was to investigate the safety and efficacy of endovenous laser ablation as a treatment for recurrent symptomatic saphenous insufficiency occurring after saphenous vein ligation and stripping. A single-center retrospective review of patients who received endovenous laser ablation as a treatment for recurrent symptomatic saphenous insufficiency after ligation and stripping between November 2003 and October 2006 was performed. Fifty-six insufficient saphenous systems were identified in 38 patients. Follow-up consisted of a clinical examination in all patients as well as selective lower-extremity duplex ultrasound as clinically indicated. All 38 patients demonstrated complete closure of the insufficient saphenous vein by clinical examination and/or duplex ultrasound evaluation. Preoperative symptoms resolved after treatment in all 38 patients. No major complications were identified. Endovenous laser ablation of recurrent symptomatic saphenous venous insufficiency is a safe and effective treatment in patients who develop recurrent symptoms after saphenous vein ligation and stripping.

  8. Radiofrequency Ablation for Liver Cancer.

    PubMed

    Jacobs, Amy

    2015-01-01

    Interventional ablative technologies aided by imaging techniques such as ultrasonography, computed tomography, and magnetic resonance imaging have been crucial in managing patients with primary liver cancer and liver metastases over the past 20 years. Several ablative technologies have been used to treat liver cancer; however, radiofrequency ablation (RFA) has emerged as the most common ablative therapy for hepatic lesions, both in the United States and globally. RFA is the treatment of choice for patients who cannot have surgical resection of the liver. This article focuses on the role of imaging in RFA treatment of primary and metastatic hepatic lesions.

  9. US-Guided Femoral and Sciatic Nerve Blocks for Analgesia During Endovenous Laser Ablation

    SciTech Connect

    Yilmaz, Saim Ceken, Kagan; Alimoglu, Emel; Sindel, Timur

    2013-02-15

    Endovenous laser ablation may be associated with significant pain when performed under standard local tumescent anesthesia. The purpose of this study was to investigate the efficacy of femoral and sciatic nerve blocks for analgesia during endovenous ablation in patients with lower extremity venous insufficiency. During a 28-month period, ultrasound-guided femoral or sciatic nerve blocks were performed to provide analgesia during endovenous laser ablation in 506 legs and 307 patients. The femoral block (n = 402) was performed at the level of the inguinal ligament, and the sciatic block at the posterior midthigh (n = 124), by injecting a diluted lidocaine solution under ultrasound guidance. After the blocks, endovenous laser ablations and other treatments (phlebectomy or foam sclerotherapy) were performed in the standard fashion. After the procedures, a visual analogue pain scale (1-10) was used for pain assessment. After the blocks, pain scores were 0 or 1 (no pain) in 240 legs, 2 or 3 (uncomfortable) in 225 legs, and 4 or 5 (annoying) in 41 legs. Patients never experienced any pain higher than score 5. The statistical analysis revealed no significant difference between the pain scores of the right leg versus the left leg (p = 0.321) and between the pain scores after the femoral versus sciatic block (p = 0.7). Ultrasound-guided femoral and sciatic nerve blocks may provide considerable reduction of pain during endovenous laser and other treatments, such as ambulatory phlebectomy and foam sclerotherapy. They may make these procedures more comfortable for the patient and easier for the operator.

  10. Esophageal papilloma: Flexible endoscopic ablation by radiofrequency

    PubMed Central

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

    2015-01-01

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

  11. Laser Navigation for Radiofrequency Ablation

    SciTech Connect

    Varro, Zoltan; Locklin, Julia K. Wood, Bradford J.

    2004-09-15

    A 45-year-old male with renal cell carcinoma secondary to von-Hippel Lindau (VHL) disease presented for radiofrequency ablation (RFA) of kidney tumors. Due to his prior history of several partial nephrectomies and limited renal reserve, RFA was chosen because of its relatively nephron-sparing nature. A laser guidance device was used to help guide probe placement in an attempt to reduce procedure time and improve targeting accuracy. The device was successful at guiding needle placement, as both tumors were located with a single pass. Follow-up CT scan confirmed accurate needle placement, showing an area of coagulation necrosis covering the previously seen tumor.

  12. [Endovenous thermal treatment of varices of the lower extremities].

    PubMed

    Bækgaard, Niels; Schroeder, Torben V

    2011-03-28

    Using a systematic review process, we identified 15 randomised controlled trials comparing either of the two endovenous thermal techniques, radiofrequency or laser ablation, with conventional open surgery for great saphenous varicose veins. The majority of trials were small and had short-term follow-up only. In general, we found no difference in reflux or recurrences in the short term. Endovenously treated patients seemed to be on sick leave for a shorter period of time than patients having undergone open surgery.

  13. Radiofrequency Ablation: A Nursing Perspective

    PubMed Central

    Locklin, Julia K.; Wood, Bradford J.

    2008-01-01

    Radiofrequency ablation (RFA) has emerged as a safe and predictable technology for treating certain patients with cancer who otherwise have few treatment options. Nurses need to be familiar with all phases of the RFA procedure to create an optimal environment for patients. This article offers a brief review of the RFA procedure and nurses' responsibilities in caring for these patients. Before RFA, nurses should focus on patient education and aggressive hydration. During the procedure, nurses can prevent injury by placing grounding pads appropriately, monitoring vital signs, and medicating patients as needed. After RFA, nurses should assess the skin puncture site, provide adequate pain relief, and, again, hydrate patients. Nurses who care appropriately for RFA recipients may help to improve patient outcomes and make an otherwise frightening procedure more comfortable. PMID:15973845

  14. Radiofrequency Ablation Beyond the Liver

    PubMed Central

    Neeman, Ziv; Wood, Bradford J.

    2008-01-01

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

  15. Endovenous laser ablation (EVLA): a review of mechanisms, modeling outcomes, and issues for debate.

    PubMed

    Malskat, Wendy S J; Poluektova, Anna A; van der Geld, Cees W M; Neumann, H A Martino; Weiss, Robert A; Bruijninckx, Cornelis M A; van Gemert, Martin J C

    2014-03-01

    Endovenous laser ablation (EVLA) is a commonly used and very effective minimally invasive therapy to manage leg varicosities. Yet, and despite a clinical history of 16 years, no international consensus on a best treatment protocol has been reached so far. Evidence presented in this paper supports the opinion that insufficient knowledge of the underlying physics amongst frequent users could explain this shortcoming. In this review, we will examine the possible modes of action of EVLA, hoping that better understanding of EVLA-related physics stimulates critical appraisal of claims made concerning the efficacy of EVLA devices, and may advance identifying a best possible treatment protocol. Finally, physical arguments are presented to debate on long-standing, but often unfounded, clinical opinions and habits. This includes issues such as (1) the importance of laser power versus the lack of clinical relevance of laser energy (Joule) as used in Joule per centimeter vein length, i.e., in linear endovenous energy density (LEED), and Joule per square centimeter vein wall area, (2) the predicted effectiveness of a higher power and faster pullback velocity, (3) the irrelevance of whether laser light is absorbed by hemoglobin or water, and (4) the effectiveness of reducing the vein diameter during EVLA therapy.

  16. Suitability of Varicose Veins for Endovenous Treatments

    SciTech Connect

    Goode, S. D.; Kuhan, G.; Altaf, N.; Simpson, R.; Beech, A.; Richards, T.; MacSweeney, S. T.; Braithwaite, B. D.

    2009-09-15

    The aim of the study was to assess the suitability of radiofrequency ablation (RFA), endovenous laser ablation (EVLA), and foam sclerotherapy (FS) for patients with symptomatic varicose veins (VVs). The study comprised 403 consecutive patients with symptomatic VVs. Data on 577 legs from 403 consecutive patients with symptomatic VVs were collected for the year 2006. Median patient age was 55 years (interquartile range 45-66), and 62% patients were women. A set of criteria based on duplex ultrasonography was used to select patients for each procedure. Great saphenous vein (GSV) reflux was present in 77% (446 of 577) of legs. Overall, 328 (73%) of the legs were suitable for at least one of the endovenous options. Of the 114 legs with recurrent GSV reflux disease, 83 (73%) were suitable to receive endovenous therapy. Patients with increasing age were less likely to be suitable for endovenous therapy (P = 0.03). Seventy-three percent of patients with VVs caused by GSV incompetence are suitable for endovenous therapy.

  17. The heat-pipe resembling action of boiling bubbles in endovenous laser ablation.

    PubMed

    van der Geld, Cees W M; van den Bos, Renate R; van Ruijven, Peter W M; Nijsten, Tamar; Neumann, H A Martino; van Gemert, Martin J C

    2010-11-01

    Endovenous laser ablation (EVLA) produces boiling bubbles emerging from pores within the hot fiber tip and traveling over a distal length of about 20 mm before condensing. This evaporation-condensation mechanism makes the vein act like a heat pipe, where very efficient heat transport maintains a constant temperature, the saturation temperature of 100 degrees C, over the volume where these non-condensing bubbles exist. During EVLA the above-mentioned observations indicate that a venous cylindrical volume with a length of about 20 mm is kept at 100 degrees C. Pullback velocities of a few mm/s then cause at least the upper part of the treated vein wall to remain close to 100 degrees C for a time sufficient to cause irreversible injury. In conclusion, we propose that the mechanism of action of boiling bubbles during EVLA is an efficient heat-pipe resembling way of heating of the vein wall.

  18. Characterization of tracked radiofrequency ablation in phantom

    SciTech Connect

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

    2007-10-15

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

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

    PubMed

    Plasencia Martínez, J M

    2015-01-01

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

  20. Effects of endovenous laser ablation on vascular tissue: molecular genetics approach

    PubMed Central

    Alur, İhsan; Dodurga, Yavuz; Güneş, Tevfik; Eroglu, Canan; Durna, Fırat; Türk, Nilay Şen; Adıgüzel, Esat; Emrecan, Bilgin

    2015-01-01

    Background: Endovenous laser ablation (EVLA) is a treatment option for lower extremity varicose veins. In the present study, we investigate to the genetic changes and possibility of living tissue in the saphenous vein wall after the EVLA procedure. Methods: Eleven saphenous vein grafts were randomized in two groups: (1) 4 cm SVG segments of performed EVLA procedure in study group, (2) 4 cm segments of SVG none performed EVLA procedure in control group. SVG were taken from the remnants of distal saphenous vein grafts prepared for the bypass procedure but not used. SVG was approximately 8 cm in length and was divided into two parts 4 cm in length. One half was exposed to laser energy, while the other half of the same vein graft was untreated as a control. EVLA was performed on complete saphenous veins in the study group. Abnormal genetic changes of the SVG were observed with a Tri-Reagent method and quantified with a Nanodrop™ spectrophotometer. Results: Histopathological changes indicated that the intima including the endothelium was completely necrotized in the study group. It was observed that intimal thermal-energy-induced injury did not reach the media. Histopathological examination showed that homogenous eosinophilic discoloration and coagulation necrosis characterized the laser related thermal damage as well. Conclusions: In this preliminary study, we found that living tissue remained in the SVG wall after application of laser ablation, and we also detected abnormal genetic changes in the study group compared with the control group. PMID:26379903

  1. Endovenous Laser Ablation and Concomitant Foam Sclerotherapy: Experience in 504 Patients

    SciTech Connect

    Yilmaz, Saim Ceken, Kagan; Alparslan, Ahmet; Durmaz, Sedat; Sindel, Timur

    2012-12-15

    Purpose: To investigate the value of endovenous laser ablation (ELA) and concomitant ultrasound-guided foam sclerotherapy (USGFS) in patients with chronic venous insufficiency. Methods: During a 6-year period, concomitant USGFS of the varicose veins were performed in 504 out of 610 patients who underwent ELA for truncal or perforating vein insufficiency. In these 504 patients (944 legs; bilateral in 440 patients), the incompetent veins were greater saphenous vein in 615 legs, small saphenous vein in 118 veins, perforating veins in 42 legs, and a combination of these in 169 legs. In all patients, after ELA of the incompetent veins, USGFS was performed for the remaining varicosities with 1-3% polidocanol foam. Patients were followed up clinically and with color Doppler ultrasound at 1, 6, and 12 months. Results: ELA was technically successful in all cases, although another venous puncture was necessary in 29 legs. Concomitant USGFS was also technically successful in all cases, but one to three additional sclerotherapy sessions were performed in 203 legs with persistent varicosities. During the follow-up, recanalization of the laser-ablated refluxing veins occurred in 16 legs (1.7%) and was treated with repeat ELA or USGFS. Major complications occurred in 1.4% of the treated legs and included skin necrosis and calf vein thrombosis. Conclusion: ELA and concomitant foam sclerotherapy is feasible and effective. The procedures are associated with a low complication rate and can be performed in both legs in the same session. Concomitant use of laser and foam may potentially decrease the recanalization rate of laser-ablated vessels.

  2. The heat-pipe resembling action of boiling bubbles in endovenous laser ablation

    PubMed Central

    van den Bos, Renate R.; van Ruijven, Peter W. M.; Nijsten, Tamar; Neumann, H. A. Martino; van Gemert, Martin J. C.

    2010-01-01

    Endovenous laser ablation (EVLA) produces boiling bubbles emerging from pores within the hot fiber tip and traveling over a distal length of about 20 mm before condensing. This evaporation-condensation mechanism makes the vein act like a heat pipe, where very efficient heat transport maintains a constant temperature, the saturation temperature of 100°C, over the volume where these non-condensing bubbles exist. During EVLA the above-mentioned observations indicate that a venous cylindrical volume with a length of about 20 mm is kept at 100°C. Pullback velocities of a few mm/s then cause at least the upper part of the treated vein wall to remain close to 100°C for a time sufficient to cause irreversible injury. In conclusion, we propose that the mechanism of action of boiling bubbles during EVLA is an efficient heat-pipe resembling way of heating of the vein wall. PMID:20644976

  3. [Effect of pharmacotherapy on course of postoperative period after endovenous thermal ablation].

    PubMed

    Stoiko, Yu M; Mazaishvili, K V; Khlevtova, T V; Tsyplyashchuk, A V; Kharitonova, S E; Akimov, S S

    2015-01-01

    The authors assessed the effect of a micronized purified flavonoid fraction (MPFF) on the course of the postoperative period after endovenous thermal ablation (EVTA). The patients of the Study Group matching by the main studied parameters to the Control Group patients were given the MPFF according to the suggested regimen for 7 days. The obtained results were analysed by means of questionnaires (CIVIQ, VCSS, VAS) and ultrasound angioscanning. The obtained findings were statistically processed by means of the program Statistica 6.0 and reliability of the results was assessed with the help of the Student t-test. Patients of the both groups showed complete stable obliteration of the target veins. No statistically significant differences of the items of the questionnaires CIVIQ and VCSS at the beginning of the study and at the last examination were revealed, differences were noted on days 2-14 after EVTA and were not statistically significant (p>0.05). Phlebotrophic therapy in the postoperative period after EVTA helps to decrease phlebitic alterations in the coagulated vein, to improve motor activity and mental psychoemotional state of the patients.

  4. Photoacoustic characterization of radiofrequency ablation lesions

    NASA Astrophysics Data System (ADS)

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

    2012-02-01

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

  5. Radiofrequency ablation for benign thyroid nodules.

    PubMed

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

    2016-09-01

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

  6. Radiofrequency thermal ablation of hepatocellular carcinoma.

    PubMed

    Allgaier, H P; Galandi, D; Zuber, I; Blum, H E

    2001-01-01

    Hepatocellular carcinoma (HCC) is one of the major malignancies worldwide. Due to advanced or decompensated liver cirrhosis, comorbidity and multicentricity of the tumor lesions, 70-80% of HCC patients are inoperable at the time of diagnosis. Radiofrequency thermal ablation (RFTA) is a new minimally invasive and sage technique for the nonsurgical treatment of HCCs. Similar to other ablation techniques, the treatment strategy depends on several factors, including the patient's clinical status, the stage of liver cirrhosis and of the HCC. RFTA can be performed percutaneously, laparoscopically or after laparotomy. Advanced RFTA equipment, refined techniques of modifying tumor tissue response to RFTA, and combined treatment strategies should lead to better response rates even in larger HCCs.

  7. Palliative Radiofrequency Ablation for Recurrent Prostate Cancer

    SciTech Connect

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

    2006-06-15

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

  8. Optical-thermal mathematical model for endovenous laser ablation of varicose veins.

    PubMed

    van Ruijven, Peter W M; Poluektova, Anna A; van Gemert, Martin J C; Neumann, H A Martino; Nijsten, Tamar; van der Geld, Cees W M

    2014-03-01

    Endovenous laser ablation (EVLA) is successfully used to treat varicose veins. However, the exact working mechanism is still not fully identified and the clinical procedure is not yet standardized. Mathematical modeling of EVLA could strongly improve our understanding of the influence of the various EVLA processes. The aim of this study is to combine Mordon's optical-thermal model with the presence of a strongly absorbing carbonized blood layer on the fiber tip. The model anatomy includes a cylindrically symmetric blood vessel surrounded by an infinite homogenous perivenous tissue. The optical fiber is located in the center of the vessel and is withdrawn with a pullback velocity. The fiber tip includes a small layer of strongly absorbing material, representing the layer of carbonized blood, which absorbs 45% of the emitted laser power. Heat transfer due to boiling bubbles is taken into account by increasing the heat conduction coefficient by a factor of 200 for temperatures above 95 °C. The temperature distribution in the blood, vessel wall, and surrounding medium is calculated from a numerical solution of the bioheat equation. The simulations were performed in MATLAB™ and validated with the aid of an analytical solution. The simulations showed, first, that laser wavelength did virtually not influence the simulated temperature profiles in blood and vessel wall, and, second, that temperatures of the carbonized blood layer varied slightly, from 952 to 1,104 °C. Our improved mathematical optical-thermal EVLA model confirmed previous predictions and experimental outcomes that laser wavelength is not an important EVLA parameter and that the fiber tip reaches exceedingly high temperatures.

  9. Fascicular ventricular tachycardia: experience with radiofrequency ablation.

    PubMed

    Magalhaes, Sónia; Gonçalves, Helena; Primo, João; Sá, Ana Paula; Silva, Paula; Rosas, Rui; Gama, Vasco

    2006-05-01

    at the tachycardia exit site failing, with no complications. If we include the success of a repeated case with three-dimensional mapping, the overall success rate was 80%. Ablation of fascicular tachycardia appears to be a good therapeutic option with a good success rate and without significant adverse events. The poor reproducibility as a consequence of contact inhibition during endocardial left ventricular mapping is the principal limiting factor. With the help of currently available mapping systems, we hope that this limitation will disappear, as it is now possible with some devices to acquire accurate information on suitable sites for subsequent radiofrequency application with little or no contact, facilitating the ablation procedure. Ablation at a site with simultaneous recording of DP and PP is considered by most authors to be more effective than that performed at the tachycardia exit site.

  10. Emerging indications of endoscopic radiofrequency ablation

    PubMed Central

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

    2015-01-01

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

  11. Radiofrequency Ablation Therapy for Solid Tumors

    SciTech Connect

    Kam, Anthony

    2002-12-04

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

  12. Radiofrequency Ablation of Intrahepatic Cholangiocarcinoma: Preliminary Experience

    SciTech Connect

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

    2010-08-15

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

  13. Laparoscopic radiofrequency ablation of neuroendocrine liver metastases.

    PubMed

    Berber, Eren; Flesher, Nora; Siperstein, Allan E

    2002-08-01

    We previously reported on the safety and efficacy of laparoscopic radiofrequency thermal ablation (RFA) for treating hepatic neuroendocrine metastases. The aim of this study is to report our 5-year RFA experience in the treatment of these challenging group of patients. Of the 222 patients with 803 liver primary and secondary tumors undergoing laparoscopic RFA between January 1996 and August 2001, a total of 34 patients with 234 tumors had neuroendocrine liver metastases. There were 25 men and 9 women with a mean +/- SEM age of 52 +/- 2 years who underwent 42 ablations. Primary tumor types included carcinoid tumor in 18 patients, medullary thyroid cancer in 7, secreting islet cell tumor in 5, and nonsecreting islet cell tumor in 4. There was no mortality, and the morbidity was 5%. The mean hospital stay was 1.1 days. Symptoms were ameliorated in 95%, with significant or complete symptom control in 80% of the patients for a mean of 10+ months (range 6-24 months). All patients were followed for a mean +/- SEM of 1.6 +/- 0.2 years (range 1.0-5.4 years). During this period new liver lesions developed in 28% of patients, new extrahepatic disease in 25%, and local liver recurrence in 13%; existing liver lesions progressed in 13%. Overall 41% of patients showed no progression of their cancer. Nine patients (27%) died. Mean +/- SEM survivals after diagnosis of primary disease, detection of liver metastases, and performance of RFA were 5.5 +/- 0.8 years, 3.0 +/- 0.3 years, and 1.6 +/- 0.2 years, respectively. Sixty-five percent of the patients demonstrated a partial or significant decrease in their tumor markers during follow-up. In conclusion, RFA provides excellent local tumor control with overnight hospitalization and low morbidity in the treatment of liver metastases from neuroendocrine tumors. It is a useful modality in the management of these challenging group of patients.

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

    PubMed Central

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

    2015-01-01

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

  15. Some controversies in endovenous laser ablation of varicose veins addressed by optical-thermal mathematical modeling.

    PubMed

    Poluektova, Anna A; Malskat, Wendy S J; van Gemert, Martin J C; Vuylsteke, Marc E; Bruijninckx, Cornelis M A; Neumann, H A Martino; van der Geld, Cees W M

    2014-03-01

    Minimally invasive treatment of varicose veins by endovenous laser ablation (EVLA) becomes more and more popular. However, despite significant research efforts performed during the last years, there is still a lack of agreement regarding EVLA mechanisms and therapeutic strategies. The aim of this article is to address some of these controversies by utilizing optical-thermal mathematical modeling. Our model combines Mordon's light absorption-based optical-thermal model with the thermal consequences of the thin carbonized blood layer on the laser fiber tip that is heated up to temperatures of around 1,000 °C due to the absorption of about 45% of the laser light. Computations were made in MATLAB. Laser wavelengths included were 810, 840, 940, 980, 1,064, 1,320, 1,470, and 1,950 nm. We addressed (a) the effect of direct light absorption by the vein wall on temperature behavior, comparing computations by using normal and zero wall absorption; (b) the prediction of the influence of wavelength on the temperature behavior; (c) the effect of the hot carbonized blood layer surrounding the fiber tip on temperature behavior, comparing wall temperatures from using a hot fiber tip and one kept at room temperature; (d) the effect of blood emptying the vein, simulated by reducing the inside vein diameter from 3 down to 0.8 mm; (e) the contribution of absorbed light energy to the increase in total energy at the inner vein wall in the time period where the highest inner wall temperature was reached; (f) the effect of laser power and pullback velocity on wall temperature of a 2-mm inner diameter vein, at a power/velocity ratio of 30 J/cm at 1,470 nm; (g) a comparison of model outcomes and clinical findings of EVLA procedures at 810 nm, 11 W, and 1.25 mm/s, and 1,470 nm, 6 W, and 1 mm/s, respectively. Interestingly, our model predicts that the dominating mechanism for heating up the vein wall is not direct absorption of the laser light by the vein wall but, rather, heat flow to the

  16. Endovascular Radiofrequency Ablation for Varicose Veins

    PubMed Central

    2011-01-01

    Executive Summary Objective 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. Background 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

  17. Comparison of Bare-Tip and Radial Fiber in Endovenous Laser Ablation with 1470 nm Diode Laser

    PubMed Central

    Kurihara, Nobuhisa

    2014-01-01

    Objective: Major side effects after endovenous laser ablation (EVLA) are pain and bruising. The aim of this study was to compare outcome and side effects after EVLA for primary varicose veins with 1470 nm diode laser using bare-tip orradial fiber. Methods: From October 2007 to December 2010, 385 patients (453 limbs) with primary varicose veins treated with 1470 nm laser were studied. Bare-tip fiber was used in 215 patients (242 limbs) (BF group) and radial fiber (ELVeSTMRadial, Biolitec AG, Germany) was used in 177 patients (211 limbs) (RF group). This study is a retrospective study and radial fiber was started for use from November 2008. Laser energy was administered at 6–12 W of power in the BF group and 10 W of power in the RF group with constant pullback of laser fiber under tumescent local anesthesia. The patients were assessed by clinical examination and venous duplex ultrasonography at 24–48 h, one week, one month, 4 months and one year follow-up postoperatively. Results: Mean operating time, length of treated vein and linear endovenous laser energy of all cases were 42.6 min, 36.2 cm and 83.4 J/cm, respectively. Major complications such as deep vein thrombosis and skin burns were not noted. Bruising (1.9% vs. 19.4%) and pain (0.9% vs. 7.4%) were significantly lower in the RF group. Cumulative occlusion rates by Kaplan-Meier method were 100% at 32 months in the RF group and 99.5% at 4 years in the BF group. Conclusion: EVLA using 1470 nm laser with the radial fiber minimized adverse effects compared with bare-tip laser fiber. (*English translation of Jpn J Vasc Surg 2013; 22: 615-621) PMID:25298824

  18. Anesthetic Management in Radiofrequency Catheter Ablation of Ventricular Tachycardia

    PubMed Central

    Naeini, Payam S.; Razavi, Mehdi; Collard, Charles D.; Tolpin, Daniel A.; Anton, James M.

    2016-01-01

    Radiofrequency catheter ablation is increasingly being used to treat patients who have ventricular tachycardia, and anesthesiologists frequently manage their perioperative care. This narrative review is intended to familiarize anesthesiologists with preprocedural, intraprocedural, and postprocedural implications of this ablation. Ventricular tachycardia typically arises from structural heart disease, most often from scar tissue after myocardial infarction. Many patients thus affected will benefit from radiofrequency catheter ablation in the electrophysiology laboratory to ablate the foci of arrhythmogenesis. The pathophysiology of ventricular tachycardia is complex, as are the technical aspects of mapping and ablating these arrhythmias. Patients often have substantial comorbidities and tenuous hemodynamic status, necessitating pharmacologic and mechanical cardiopulmonary support. General anesthesia and monitored anesthesia care, when used for sedation during ablation, can lead to drug interactions and side effects in the presence of ventricular tachycardia, so anesthesiologists should also be aware of potential perioperative complications. We discuss variables that can help anesthesiologists safely guide patients through the challenges of radiofrequency catheter ablation of ventricular tachycardia. PMID:28100967

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

    SciTech Connect

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

    2006-04-15

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

  20. Osteoid osteoma of the cuboid managed by percutaneous radiofrequency ablation.

    PubMed

    Chakraverty, Julian; Al-Mokhtar, Namir; James, Steven L

    2014-01-01

    We present details of a case of osteoid osteoma of the tarsal cuboid bone. Osteoid osteoma arising in the foot is not very common, and localization in the cuboid is rare. To our knowledge, this is the first case of osteoid osteoma of the cuboid bone treated successfully by percutaneous radiofrequency ablation.

  1. [Thrombus visualisation during radiofrequency catheter ablation. A case report].

    PubMed

    Maciag, Aleksander; Szwed, Hanna; Pytkowski, Mariusz; Kraska, Alicja; Sterliński, Maciej

    2005-10-01

    We report two patients in whom thrombus formation during radiofrequency catheter ablation was detected by echocardiography. Resolution of thrombus after intravenous use of heparin was observed in both patients. Transesophageal and intracardiac echocardiography may be useful in management of this complication.

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

    SciTech Connect

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

    2005-04-15

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

  3. Radiofrequency Ablation for Iatrogenic Thyroid Artery Pseudoaneurysm: Initial Experience.

    PubMed

    Jun, Ye Kyeong; Jung, So Lyung; Byun, Ho Kyun; Baek, Jung Hwan; Sung, Jin Yong; Sim, Jung Suk

    2016-10-01

    Eight iatrogenic thyroid pseudoaneurysms (ITPAs) after thyroid biopsy are reported. The mean ITPA diameter was 7.2 mm (range 4 to 12 mm). Ultrasound (US)-guided compression was initially performed at the neck of the ITPA in all cases. Among them, 4 ITPAs persisted (50%) in which radiofrequency (RF) ablation was performed. Mean RF ablation time and power were 13.5 seconds (range 5 to 24 seconds) and 20 W (range 10 to 50 W), respectively. All 4 cases were treated with RF ablation without any complications.

  4. A Complicated Postsurgical Echinococcal Cyst Treated with Radiofrequency Ablation

    SciTech Connect

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

    2008-01-15

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

  5. Irrigated Tip Catheters for Radiofrequency Ablation in Ventricular Tachycardia

    PubMed Central

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

    2015-01-01

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

  6. Microwave Ablation Compared to Radiofrequency Ablation for Hepatic Lesions: A Meta-Analysis.

    PubMed

    Huo, Ya Ruth; Eslick, Guy D

    2015-08-01

    To evaluate the efficacy and safety of microwave (MW) ablation compared with radiofrequency (RF) ablation for hepatic lesions by using meta-analytic techniques. Overall, 16 studies involving 2,062 patients were included. MW ablation was found to have significantly better 6-year overall survival than RF ablation (odds ratio, 1.64, 95% confidence interval, 1.15-2.35), but this was based on a few articles (n = 3 of 16). MW ablation and RF ablation had similar 1-5-year overall survival, disease-free survival, local recurrence rate, and adverse events. Based on similar safety and efficacy outcomes, either MW ablation or RF ablation may be used for effective local hepatic therapy.

  7. Effects of Fentanyl and Morphine on Shivering During Spinal Anesthesia in Patients Undergoing Endovenous Ablation of Varicose Veins

    PubMed Central

    Onk, Didem; Ayazoğlu, Tülin Akarsu; Kuyrukluyıldız, Ufuk; Aksüt, Mehmet; Bedir, Zehra; Küpeli, İlke; Onk, Oruç Alper; Alagöl, Ayşin

    2016-01-01

    Background We sought to investigate the effect of morphine and fentanyl on shivering when used adjunctively with bupivacaine during spinal anesthesia in patients undergoing varicose vein surgery on an outpatient basis. Material/Methods The study included a total of 90 patients, aged 25–45 years, ASA I–II, scheduled to undergo endovenous laser ablation under spinal anesthesia for lower extremity venous insufficiency/varicose vein disease. Patients were randomly allocated into 3 groups: Group M (morphine group) received 5 mg 0.5% hyperbaric bupivacaine + 0.1 mg morphine, Group F (fentanyl group) received 5 mg 0.5% hyperbaric bupivacaine + 25 μg fentanyl, and Group C (control group) received 5 mg 0.5% hyperbaric bupivacaine + physiologic saline. The level of sensory blockade was assessed with pin-prick test and the level of motor blockade was assessed with Bromage scale at 5-min intervals. Shivering grade and time to first postoperative analgesic requirement was recorded. Results Level and time of sensory block showed a slight but insignificant increase in the Morphine Group and Fentanyl Group. Time of postoperative analgesic requirement was significantly longer in patients who received morphine (p<0.05). Shivering was significantly less common in patients who received morphine and fentanyl than in patients who are in the Control Group (p<0.02). Conclusions Morphine or fentanyl may be used as adjunctives to spinal anesthesia to prevent shivering in patients undergoing venous surgery. PMID:26871238

  8. Radiofrequency Ablation of Persistent Atrial Fibrillation

    PubMed Central

    Hussein, Ayman A.; Saliba, Walid I.; Barakat, Amr; Bassiouny, Mohammed; Chamsi-Pasha, Mohammed; Al-Bawardy, Rasha; Hakim, Ali; Tarakji, Khaldoun; Baranowski, Bryan; Cantillon, Daniel; Dresing, Thomas; Tchou, Patrick; Martin, David O.; Varma, Niraj; Bhargava, Mandeep; Callahan, Thomas; Niebauer, Mark; Kanj, Mohamed; Chung, Mina; Natale, Andrea; Lindsay, Bruce D.; Wazni, Oussama M.

    2017-01-01

    Background Various ablation strategies of persistent atrial fibrillation (PersAF) have had disappointing outcomes, despite concerted clinical and research efforts, which could reflect progressive atrial fibrillation–related atrial remodeling. Methods and Results Two-year outcomes were assessed in 1241 consecutive patients undergoing first-time ablation of PersAF (2005–2012). The time intervals between the first diagnosis of PersAF and the ablation procedures were determined. Patients had echocardiograms and measures of B-type natriuretic peptide and C-reactive protein before the procedures. The median diagnosis-to-ablation time was 3 years (25th–75th percentiles 1–6.5). With longer diagnosis-to-ablation time (based on quartiles), there was a significant increase in recurrence rates in addition to an increase in B-type natriuretic peptide levels (P=0.01), C-reactive protein levels (P<0.0001), and left atrial size (P=0.03). The arrhythmia recurrence rates over 2 years were 33.6%, 52.6%, 57.1%, and 54.6% in the first, second, third, and fourth quartiles, respectively (Pcategorical<0.0001). In Cox Proportional Hazard analyses, B-type natriuretic peptide levels, C-reactive protein levels, and left atrial size were associated with arrhythmia recurrence. The diagnosis-to-ablation time had the strongest association with the ablation outcomes which persisted in multivariable Cox analyzes (hazard ratio for recurrence per +1Log diagnosis-to-ablation time 1.27, 95% confidence interval 1.14–1.43; P<0.0001; hazard ratio fourth versus first quartile 2.44, 95% confidence interval 1.68–3.65; Pcategorical<0.0001). Conclusions In patients with PersAF undergoing ablation, the time interval between the first diagnosis of PersAF and the catheter ablation procedure had a strong association with the ablation outcomes, such as shorter diagnosis-to-ablation times were associated with better outcomes and in direct association with markers of atrial remodeling. PMID:26763227

  9. The Efficacy of Femoral Block and Unilateral Spinal Anaesthesia on Analgesia, Haemodynamics and Mobilization in Patients undergoing Endovenous Ablation in the Lower Extremity

    PubMed Central

    Öztürk, Tülün; Çevikkalp, Eralp; Nizamoglu, Funda; Özbakkaloğlu, Alper; Topcu, İsmet

    2016-01-01

    Objective This study aimed to investigate the efficacy of femoral block and unilateral spinal anaesthesia on analgesia, haemodynamics and mobilization during endovenous ablation in patients with lower extremity venous insufficiency. Methods Forty patients of ASA physical status I and II, with ages ranging between 30 and 45 years, and who were scheduled for endovenous laser ablation for varicose veins were prospectively enrolled in this study. Patients were randomized into a unilateral spinal anaesthesia group (group HS, n=20) or a femoral block group (group F, n=20). Group HS received 7.5–10 mg of heavy bupivacaine for unilateral spinal anaesthesia, while group F received 100 mg prilocaine for femoral block with ultrasound guidance. The level of motor blockage (Bromage score), visual pain score, mean heart rate and mean arterial pressures were recorded at postoperative 0, 1, 2, 3d and 6 h, respectively. Results Perioperative visual pain score values in both groups were <4. None of the groups required an additional analgesic agent. Bromage scores were significantly lower in group F than in group HS during the postoperative period (p<0.01). Motor function returned to normal in all patients at 3 h in group F and at 6 h in group HS. Postoperative mean heart rate and arterial pressure did not differ between the groups (p>0.05). Conclusion In patients with lower extremity venous insufficiency who were undergoing endovenous laser ablation, an ultrasound-guided femoral block provided similar analgesia with that of unilateral spinal anaesthesia. In group F, the duration of anaesthesia and mobilization time was shorter. PMID:27366565

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

    SciTech Connect

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

    2012-08-15

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

  11. Endometrial ablation

    MedlinePlus

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

  12. Diaphragmatic Hernia After Radiofrequency Ablation for Hepatocellular Carcinoma

    SciTech Connect

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

    2011-02-15

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

  13. Model-based optimal planning of hepatic radiofrequency ablation.

    PubMed

    Chen, Qiyong; Müftü, Sinan; Meral, Faik Can; Tuncali, Kemal; Akçakaya, Murat

    2016-07-19

    This article presents a model-based pre-treatment optimal planning framework for hepatic tumour radiofrequency (RF) ablation. Conventional hepatic radiofrequency (RF) ablation methods rely on pre-specified input voltage and treatment length based on the tumour size. Using these experimentally obtained pre-specified treatment parameters in RF ablation is not optimal to achieve the expected level of cell death and usually results in more healthy tissue damage than desired. In this study we present a pre-treatment planning framework that provides tools to control the levels of both the healthy tissue preservation and tumour cell death. Over the geometry of tumour and surrounding tissue, we formulate the RF ablation planning as a constrained optimization problem. With specific constraints over the temperature profile (TP) in pre-determined areas of the target geometry, we consider two different cost functions based on the history of the TP and Arrhenius index (AI) of the target location, respectively. We optimally compute the input voltage variation to minimize the damage to the healthy tissue while ensuring a complete cell death in the tumour and immediate area covering the tumour. As an example, we use a simulation of a 1D symmetric target geometry mimicking the application of single electrode RF probe. Results demonstrate that compared to the conventional methods both cost functions improve the healthy tissue preservation.

  14. Mathematical Modeling of Radiofrequency Ablation for Varicose Veins

    PubMed Central

    Choi, Sun Young; Kwak, Byung Kook

    2014-01-01

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

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

    PubMed Central

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

    2001-01-01

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


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

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

    PubMed

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

    2016-02-23

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

  17. Radiofrequency thermal ablation in painful myeloma of the clavicle.

    PubMed

    Gharaei, Helen; Imani, Farnad; Vakily, Masoud

    2014-01-01

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

  18. Radiofrequency Thermal Ablation in Painful Myeloma of the Clavicle

    PubMed Central

    Imani, Farnad; Vakily, Masoud

    2014-01-01

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

  19. Incidence and Cause of Hypertension During Adrenal Radiofrequency Ablation

    SciTech Connect

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

    2012-12-15

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

  20. Chronic incomplete atrioventricular block induced by radiofrequency catheter ablation

    SciTech Connect

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

    1989-10-01

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

  1. Cost analysis of radiofrequency catheter ablation for atrial fibrillation.

    PubMed

    Gorenek, Bulent; Kudaiberdieva, Gulmira

    2013-09-10

    Atrial fibrillation is the most common arrhythmia associated with increased mortality and morbidity. Its management requires high healthcare expenditures; 52%-70% of expenses for AF care are constituted by hospitalization costs. The current management strategies of pharmacological rhythm control and pharmacological or invasive rate control show no difference in impact on major outcomes in patients with AF. Radiofrequency catheter ablation (RFA) has been shown to reduce the risk of AF recurrence, improve quality of life and reduce hospitalization rate as compared to pharmacological rhythm control and rate control strategies. This review summarizes current knowledge on cost and cost-effectiveness analysis of RFA for patients with atrial fibrillation.

  2. Treatment of bone tumours by radiofrequency thermal ablation.

    PubMed

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

    2009-03-01

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

  3. Bronchopleural Fistula After Radiofrequency Ablation of Lung Tumours

    SciTech Connect

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

    2011-02-15

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

  4. [Radiofrequency ablation of a symptomatic benign thyroid nodule].

    PubMed

    van Ginhoven, T M; Massolt, E T; Bijdevaate, D C; Peeters, R P; Burgers, J W A; Moelker, A

    2016-01-01

    Radiofrequency ablation (RFA) enables the ablation of selected tissue by means of heat. For the first time in the Netherlands, RFA is being used to treat patients with benign thyroid nodules. RFA is able to reduce the volume of a nodule that may be causing cosmetic complaints or problems due to mass effect. This avoids the need for surgery or treatment with radioactive iodine in this benign condition. The average reduction in size is 80% in the first year, leading to a considerable decrease in both symptomatic and cosmetic complaints. At Erasmus Medical Centre, Rotterdam, the Netherlands, this technique has been introduced in accordance with current guidelines, and it is expected that other centres of excellence will follow in implementing it. It is important that the initial experiences with this technique in the Netherlands in terms of effectiveness, risks and patient satisfaction should be monitored before RFA becomes routine treatment.

  5. Endovenous Laser Ablation of Varicose Veins Preserves Biological Properties of Vascular Endothelium and Modulates Proinflammatory Agent Profile More Favorably Than Classic Vein Stripping

    PubMed Central

    Uruski, Paweł; Aniukiewicz, Krzysztof; Mikuła-Pietrasik, Justyna; Sosińska, Patrycja; Tykarski, Andrzej; Krasiński, Zbigniew

    2017-01-01

    Here we compared effect of serum from varicose patients undergoing endovenous laser ablation (EVLA) and classic vein stripping (CVS) on biological properties of endothelial cells and on the local and systemic profiles of proinflammatory agents. Results showed that serum from EVLA patients improved proliferation and reduced senescence and oxidative stress in the endothelial cells, as compared with the serum from CVS patients. These effects were related to a suppressed activity of TGF-β1, the level of which in the serum from the EVLA patients was decreased. Medium generated by the cells subjected to EVLA serum contained decreased amounts of ICAM-1, VCAM-1, and E-selectin and increased amount of uPA, whereas the serum itself contained decreased concentrations of ICAM-1, E-selectin, and P-selectin and increased concentrations of uPA, PAI-1, and TFPI. Both EVLA and CVS resulted in diversified patients' reaction with respect to a direction of postprocedure changes in proinflammatory factors' serum level. Analysis of proportions showed that the groups differed remarkably in case of ICAM-1 and ET-1, the level of which declined in a higher fraction of patients treated endovenously. Our findings indicate that EVLA preserves better than CVS the functionality of vascular endothelium and modulates better both local and systemic profile of proinflammatory mediators. PMID:28316983

  6. Radiofrequency ablation of hepatocellular carcinoma: pros and cons.

    PubMed

    Rhim, Hyunchul; Lim, Hyo K

    2010-09-01

    Among locoregional treatments for hepatocellular carcinoma (HCC), radiofrequency ablation (RFA) has been accepted as the most popular alternative to curative transplantation or resection, and it shows an excellent local tumor control rate and acceptable morbidity. The benefits of RFA have been universally validated by the practice guidelines of international societies of hepatology. The main advantages of RFA include 1) it is minimally invasive with acceptable morbidity, 2) it enables excellent local tumor control, 3) it has promising long-term survival, and 4) it is a multimodal approach. Based on these pros, RFA will play an important role in managing the patient with early HCC (smaller than 3 cm with fewer than four tumors). The main limitations of current RFA technology in hepatic ablation include 1) limitation of ablation volume, 2) technically infeasible in some tumors due to conspicuity and dangerous location, and 3) the heat-sink effect. Many technical approaches have been introduced to overcome those limitations, including a novel guiding modality, use of artificial fluid or air, and combined treatment strategies. RFA will continue to play a role as a representative ablative modality in the management of HCC, even in the era of targeted agents.

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

    PubMed

    Varghese, T; Daniels, M J

    2004-07-01

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

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

    PubMed Central

    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

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

    SciTech Connect

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

    2006-04-15

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

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

    SciTech Connect

    Baere, Thierry de

    2011-04-15

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

  11. Bilateral Intra-Articular Radiofrequency Ablation for Cervicogenic Headache

    PubMed Central

    Tang, Teresa; Taftian, David; Chhatre, Akhil

    2017-01-01

    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. PMID:28149652

  12. Quality Improvement Guidelines for Radiofrequency Ablation of Liver Tumours

    SciTech Connect

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

    2010-02-15

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

  13. Thermal ablation of liver metastases from colorectal cancer: radiofrequency, microwave and laser ablation therapies.

    PubMed

    Vogl, Thomas J; Farshid, Parviz; Naguib, Nagy N N; Darvishi, Abbas; Bazrafshan, Babak; Mbalisike, Emmanuel; Burkhard, Thorsten; Zangos, Stephan

    2014-07-01

    Surgery is currently considered the treatment of choice for patients with colorectal cancer liver metastases (CRLM) when resectable. The majority of these patients can also benefit from systemic chemotherapy. Recently, local or regional therapies such as thermal ablations have been used with acceptable outcomes. We searched the medical literature to identify studies and reviews relevant to radiofrequency (RF) ablation, microwave (MW) ablation and laser-induced thermotherapy (LITT) in terms of local progression, survival indexes and major complications in patients with CRLM. Reviewed literature showed a local progression rate between 2.8 and 29.7 % of RF-ablated liver lesions at 12-49 months follow-up, 2.7-12.5 % of MW ablated lesions at 5-19 months follow-up and 5.2 % of lesions treated with LITT at 6-month follow-up. Major complications were observed in 4-33 % of patients treated with RF ablation, 0-19 % of patients treated with MW ablation and 0.1-3.5 % of lesions treated with LITT. Although not significantly different, the mean of 1-, 3- and 5-year survival rates for RF-, MW- and laser ablated lesions was (92.6, 44.7, 31.1 %), (79, 38.6, 21 %) and (94.2, 61.5, 29.2 %), respectively. The median survival in these methods was 33.2, 29.5 and 33.7 months, respectively. Thermal ablation may be an appropriate alternative in patients with CRLM who have inoperable liver lesions or have operable lesions as an adjunct to resection. However, further competitive evaluation should clarify the efficacy and priority of these therapies in patients with colorectal cancer liver metastases.

  14. Percutaneous Radiofrequency Ablation for Treatment of Recurrent Retroperitoneal Liposarcoma

    SciTech Connect

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

    2008-07-15

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

  15. Primary papillary thyroid carcinoma previously treated incompletely with radiofrequency ablation.

    PubMed

    Kim, Hoon Yub; Ryu, Woo Sang; Woo, Sang Uk; Son, Gil Soo; Lee, Eun Sook; Lee, Jae Bok; Bae, Jeoung Won

    2010-01-01

    Radiofrequency ablation (RFA) recently has been applied to benign thyroid nodules, mainly for the cosmetic reasons, and limited cases of local recurrences or focal distant metastases of well-differentiated thyroid cancer, in the high-risk reoperative condition or for the palliative purpose. But no report has been made on the RFA for primary thyroid cancer to date. We report on a patient with primary papillary carcinoma of thyroid gland who had undergone RFA before the cytological diagnosis of malignancy, later referred and treated with robotic surgery successfully. We can learn the following lessons from our case; (1) the RFA for operable primary thyroid malignancy should be avoided, because of the possibility of remnant viable cancer and undetectable nodal metastasis, and (2) robotic or endoscopic thyroid surgery may be a feasible operative method for benign or malignant thyroid nodules previously treated with RFA.

  16. Stereotactic Radiofrequency Ablation of Unresectable Intrahepatic Cholangiocarcinomas: A Retrospective Study

    SciTech Connect

    Haidu, Marion; Dobrozemsky, Georg; Schullian, Peter Widmann, Gerlig; Klaus, Alexander Weiss, Helmut Margreiter, Raimund; Bale, Reto

    2012-10-15

    Purpose: To evaluate treatment effects, complications, and outcome of percutaneous stereotactic radiofrequency ablation (SRFA) of intrahepatic cholangiocarcinoma (ICC). Patients and Methods: Eleven consecutive patients (nine men and two women) with a total of 36 inoperable ICCs (18 initial lesions, 16 lesions newly detected during follow-up, and two local recurrences) underwent SRFA between December 2004 and June 2010. Two different radiofrequency ablation (RFA) devices with internally cooled electrodes were used. Tumor diameters ranged from 0.5 to 10 cm (median 3.0 cm). A total of 23 SRFA sessions were performed. The efficacy of SRFA was evaluated by contrast-enhanced computed tomography or magnetic resonance imaging 1 month after treatment and then every 3 months. Results: Primary technical effectiveness rate was 92%. Further follow-up every 3 months revealed three local recurrences (8%), two of which were successfully retreated, resulting in a secondary technical effectiveness rate of 98%. After a total of 23 RFA sessions, three major complications occurred (13%) that could be managed interventionally. Mean follow-up time was 35 months (range 12-81 months). One- and 3-year overall survival rates were 91 and 71%, respectively. The median overall survival was 60 months (according to the life table method). Eight (73%) of 11 patients were still alive at the end of follow-up. Conclusion: SRFA is effective in the treatment of unresectable ICC even if the tumor is large and located close to major vessels. SRFA shows a survival benefit compared to other palliative treatment options and may also be considered as the first-line local treatment of ICCs in selected patients.

  17. Value of radiofrequency ablation in the treatment of hepatocellular carcinoma

    PubMed Central

    Feng, Kai; Ma, Kuan-Sheng

    2014-01-01

    Hepatocellular carcinoma (HCC) is a malignant disease that substantially affects public health worldwide. It is especially prevalent in east Asia and sub-Saharan Africa, where the main etiology is the endemic status of chronic hepatitis B. Effective treatments with curative intent for early HCC include liver transplantation, liver resection (LR), and radiofrequency ablation (RFA). RFA has become the most widely used local thermal ablation method in recent years because of its technical ease, safety, satisfactory local tumor control, and minimally invasive nature. This technique has also emerged as an important treatment strategy for HCC in recent years. RFA, liver transplantation, and hepatectomy can be complementary to one another in the treatment of HCC, and the outcome benefits have been demonstrated by numerous clinical studies. As a pretransplantation bridge therapy, RFA extends the average waiting time without increasing the risk of dropout or death. In contrast to LR, RFA causes almost no intra-abdominal adhesion, thus producing favorable conditions for subsequent liver transplantation. Many studies have demonstrated mutual interactions between RFA and hepatectomy, effectively expanding the operative indications for patients with HCC and enhancing the efficacy of these approaches. However, treated tumor tissue remains within the body after RFA, and residual tumors or satellite nodules can limit the effectiveness of this treatment. Therefore, future research should focus on this issue. PMID:24876721

  18. Palliation of Soft Tissue Cancer Pain With Radiofrequency Ablation

    PubMed Central

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

    2008-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  20. Palliative Treatment of Rectal Carcinoma Recurrence Using Radiofrequency Ablation

    SciTech Connect

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

    2012-08-15

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  3. Treatment of Uterine Myomas by Radiofrequency Thermal Ablation

    PubMed Central

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

    2015-01-01

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

  4. Outcome after Radiofrequency Ablation of Sarcoma Lung Metastases

    SciTech Connect

    Koelblinger, Claus; Strauss, Sandra; Gillams, Alice

    2013-05-14

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

  5. Use of radiofrequency ablation in benign thyroid nodules: a literature review and updates.

    PubMed

    Wong, Kai-Pun; Lang, Brian Hung-Hin

    2013-01-01

    Successful thermal ablation using radiofrequency has been reported in various tumors including liver or kidney tumors. Nonsurgical minimally invasive ablative therapy such as radiofrequency ablation (RFA) has been reported to be a safe and efficient treatment option in managing symptomatic cold thyroid nodules or hyperfunctioning thyroid nodules. Pressure and cosmetic symptoms have been shown to be significantly improved both in the short and long terms after RFA. For hyperfunctioning thyroid nodules, RFA is indicated for whom surgery or radioiodine are not indicated or ineffective or for those who refuse surgery or radio-iodine. Improvement of thyroid function with decreased need for antithyroid medications has been reported. Complication rate is relatively low. By reviewing the current literature, we reported its efficacy and complications and compared the efficacy of RFA relative to other ablative options such as ethanol ablation and laser ablation.

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

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  7. Radiofrequency ablation to treat non-small cell lung cancer and pulmonary metastases.

    PubMed

    Fernando, Hiran C

    2008-02-01

    Radiofrequency ablation is being reported with increasing frequency for the treatment of lung tumors. Several studies have demonstrated that this is a feasible and safe approach. Intermediate outcomes are now becoming available. Although tumors up to 5 cm in size can be effectively treated with radiofrequency ablation, results are better for smaller tumors (3 cm or less). This review describes the techniques, available ablation devices, and the potential role of radiofrequency ablation for non-small cell lung cancer (NSCLC) and pulmonary metastases. Resection (lobar or sublobar) should remain the standard therapy for NSCLC. Radiofrequency ablation may be better than conventional external-beam radiation for the treatment of the high-risk individual with NSCLC. Preliminary results for pulmonary metastases are similar to those reported after resection. In addition, patients with pulmonary metastases have been demonstrated to develop recurrences even after thoracotomy and bimanual palpation of the lung. Radiofrequency ablation may be an alternative to resection for the patient with small-diameter pulmonary metastases, and future study of this may be indicated.

  8. Percutaneous treatment of bone tumors by radiofrequency thermal ablation.

    PubMed

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

    2011-01-01

    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.

  9. PET guidance for liver radiofrequency ablation: an evaluation

    NASA Astrophysics Data System (ADS)

    Lei, Peng; Dandekar, Omkar; Mahmoud, Faaiza; Widlus, David; Malloy, Patrick; Shekhar, Raj

    2007-03-01

    Radiofrequency ablation (RFA) is emerging as the primary mode of treatment of unresectable malignant liver tumors. With current intraoperative imaging modalities, quick, precise, and complete localization of lesions remains a challenge for liver RFA. Fusion of intraoperative CT and preoperative PET images, which relies on PET and CT registration, can produce a new image with complementary metabolic and anatomic data and thus greatly improve the targeting accuracy. Unlike neurological images, alignment of abdominal images by combined PET/CT scanner is prone to errors as a result of large nonrigid misalignment in abdominal images. Our use of a normalized mutual information-based 3D nonrigid registration technique has proven powerful for whole-body PET and CT registration. We demonstrate here that this technique is capable of acceptable abdominal PET and CT registration as well. In five clinical cases, both qualitative and quantitative validation showed that the registration is robust and accurate. Quantitative accuracy was evaluated by comparison between the result from the algorithm and clinical experts. The accuracy of registration is much less than the allowable margin in liver RFA. Study findings show the technique's potential to enable the augmentation of intraoperative CT with preoperative PET to reduce procedure time, avoid repeating procedures, provide clinicians with complementary functional/anatomic maps, avoid omitting dispersed small lesions, and improve the accuracy of tumor targeting in liver RFA.

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

    PubMed Central

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

    2015-01-01

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

  11. Supercomputer Simulation of Radio-frequency Hepatic Tumor Ablation

    NASA Astrophysics Data System (ADS)

    Kosturski, N.; Margenov, S.

    2010-11-01

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

  12. Aggressive tumor recurrence after radiofrequency ablation for hepatocellular carcinoma.

    PubMed

    Kang, Tae Wook; Lim, Hyo Keun; Cha, Dong Ik

    2017-03-01

    Image-guided radiofrequency ablation (RFA) is an evolving and growing treatment option for patients with hepatocellular carcinoma (HCC) and hepatic metastasis. RFA offers significant advantages as it is less invasive than surgery and carries a low risk of major complications. However, serious complications, including aggressive tumor recurrence, may be observed during follow-up, and recently, mechanical or thermal damage during RFA has been proposed to be one of the causes of this kind of recurrence. Although the exact mechanism of this still remains unclear, physicians should be familiar with the imaging features of aggressive tumor recurrence after RFA for HCC and its risk factors. In addition, in order to prevent or minimize this newly recognized tumor recurrence, a modified RFA technique, combined RFA treatments with transarterial chemoembolization, and cryoablation can be used as alternative treatments. Ultimately, combining an understanding of this potential complication of RFA with an understanding of the possible risk factors for aggressive tumor recurrence and choosing alternative treatments are crucial to optimize clinical outcomes in each patient with HCC.

  13. Aggressive tumor recurrence after radiofrequency ablation for hepatocellular carcinoma

    PubMed Central

    Kang, Tae Wook; Lim, Hyo Keun; Cha, Dong Ik

    2017-01-01

    Image-guided radiofrequency ablation (RFA) is an evolving and growing treatment option for patients with hepatocellular carcinoma (HCC) and hepatic metastasis. RFA offers significant advantages as it is less invasive than surgery and carries a low risk of major complications. However, serious complications, including aggressive tumor recurrence, may be observed during follow-up, and recently, mechanical or thermal damage during RFA has been proposed to be one of the causes of this kind of recurrence. Although the exact mechanism of this still remains unclear, physicians should be familiar with the imaging features of aggressive tumor recurrence after RFA for HCC and its risk factors. In addition, in order to prevent or minimize this newly recognized tumor recurrence, a modified RFA technique, combined RFA treatments with transarterial chemoembolization, and cryoablation can be used as alternative treatments. Ultimately, combining an understanding of this potential complication of RFA with an understanding of the possible risk factors for aggressive tumor recurrence and choosing alternative treatments are crucial to optimize clinical outcomes in each patient with HCC. PMID:28349677

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    SciTech Connect

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

    2009-07-15

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

  17. Paroxysmal atrial fibrillation ablation: Achieving permanent pulmonary vein isolation by point-by-point radiofrequency lesions

    PubMed Central

    Pedrote, Alonso; Acosta, Juan; Jáuregui-Garrido, Beatriz; Frutos-López, Manuel; Arana-Rueda, Eduardo

    2017-01-01

    Pulmonary vein isolation by point-by-point radiofrequency catheter ablation constitutes the cornerstone of catheter ablation strategies for the treatment of atrial fibrillation. However, despite advances in pulmonary vein isolation ablation strategies, long-term success rates after ablation remain suboptimal, which highlights the need to develop techniques to achieve more durable lesions. Strategies proposed to improve the durability of pulmonary vein isolation can be divided into two groups: Those addressed to improving the quality of the lesion and those that optimize the detection of acute PV reconnection during the ablation procedure. This manuscript reviews the role and potential benefits of these techniques according to current clinical evidence.

  18. ClariVein® – Early results from a large single-centre series of mechanochemical endovenous ablation for varicose veins

    PubMed Central

    Kam, JW; Gaunt, ME

    2016-01-01

    Objectives This study assessed the effectiveness and patient experience of the ClariVein® endovenous occlusion catheter for varicose veins from a large single-centre series in the UK. Methods A total of 300 patients (371 legs) underwent ClariVein® treatment for their varicose veins; 184 for great saphenous vein (GSV) incompetence, 62 bilateral GSV, 23 short saphenous vein (SSV), 6 bilateral SSV and 25 combined unilateral great saphenous vein and SSV. Patients were reviewed at an interval of two months post procedure and underwent Duplex ultrasound assessment. Postoperative complications were recorded along with patient satisfaction. Results All 393 procedures were completed successfully under local anaesthetic. Complete occlusion of the treated vein was initially achieved in all the patients, but at eight weeks’ follow-up, there was only partial obliteration in 13/393 (3.3%) veins. These were all successfully treated with ultrasound-guided foam sclerotherapy. Procedures were well tolerated with a mean pain score of 0.8 (0–10). No significant complications were reported. Conclusions ClariVein® can be used to ablate long and short saphenous varicose veins on a walk-in–walk-out basis. Bilateral procedures can be successfully performed, and these are well tolerated as can multiple veins in the same leg. Early results are promising but further evaluation and longer term follow-up are required. PMID:26908638

  19. Improvements of deep vein reflux following radiofrequency ablation for saphenous vein incompetence.

    PubMed

    Kim, Suh Min; Jung, In Mok; Chung, Jung Kee

    2017-02-01

    Objectives The aim of this study was to describe the changes of deep vein reflux after radiofrequency ablation for great saphenous vein incompetence. Method The data on 139 limbs which were treated with radiofrequency ablation for great saphenous vein incompetence were prospectively collected and reviewed. Results Deep vein reflux was present in 43 of 139 limbs (30.9%). There were no significant differences in the rate of successful closure, the incidence of procedure-related complications, and the improvements of symptoms and quality of life between the limbs with or without deep vein reflux. With a mean follow-up of 5.9 months, the peak reflux velocity and duration of reflux were improved in all limbs with deep vein reflux and it was completely corrected in 13 limbs (30.2%) after radiofrequency ablation. Conclusions The presence of deep vein reflux does not affect the treatment outcomes of radiofrequency ablation for great saphenous vein incompetence and is improved in all patients. Deep vein reflux is not a barrier to performing radiofrequency ablation.

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

    PubMed

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

    2014-04-01

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

  1. Endoscopic Resection and Radiofrequency Ablation for Early Esophageal Neoplasia

    PubMed Central

    Belghazi, Kamar; Bergman, Jacques; Pouw, Roos E.

    2016-01-01

    Background In the last few decades, endoscopic treatment of early neoplastic lesions in the esophagus has established itself as a valid and less invasive alternative to surgical resection. Endoscopic resection (ER) is the cornerstone of endoscopic therapy. Next to the curative potential of ER, by removing neoplastic lesions, ER may also serve as a diagnostic tool. The relatively large tissue specimens obtained with ER enable accurate histological staging of a lesion, allowing for optimal decision-making for further patient management. ER was pioneered in Japan, mainly for the resection of gastric lesions and squamous esophageal neoplasia, and also Western countries have been increasingly implementing ER in the treatment of early gastroesophageal neoplasia, mostly associated with Barrett's esophagus (BE). In BE, however, there is still a risk of metachronous lesions in the remainder of the Barrett's after focal ER. Additional treatment of all Barrett's mucosa is therefore advised. Currently, the most effective method for this is by using radiofrequency ablation (RFA). This review will provide an overview of indications for ER and RFA. Key Messages and Conclusions Endoscopic management of early esophageal neoplasia is a safe and valid alternative to surgery and is nowadays the treatment of choice. ER is the mainstay of endoscopic management of early esophageal neoplasia since it allows for removal of neoplastic lesions and provides a large tissue specimen for histological evaluation. In case of early neoplasia in BE, focal ER should be complemented by eradication of the remaining Barrett's mucosa. RFA has proven to be a safe and effective modality to achieve complete eradication of Barrett's mucosa. PMID:27333327

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

    PubMed Central

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

    2014-01-01

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

  3. Single-Session Radiofrequency Ablation of Bilateral Lung Metastases

    SciTech Connect

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

    2012-08-15

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

  4. Preoperative radiofrequency ablation in painful osteolytic long bone metastases.

    PubMed

    Di Francesco, Alexander; Flamini, Stefano; Zugaro, Luigi; Zoccali, Carmine

    2012-08-01

    This study aimed to determine whether Radiofrequency Ablation (RFA) followed by prophylactic internal fixation produces better palliation in terms of pain and reduces the need for blood transfusion more than radiotherapy and surgical stabilization (RT-SS). Patients with solitary long bone metastases and a pain score of 5 or more on the VAS scale were selected. Fifteen patients were treated with RFA and surgical stabilization (RFA-SS) and were compared with a matched group (15 subjects) treated by radiotherapy and surgical stabilization (RT-SS). A complete response in terms of pain relief at 12 weeks was documented in 20% (3/15) and 533% (8/15) of the subjects treated by RT-SS or RFA-SS, respectively (p = 0.027). The overall response rate at 12 weeks was 93.3% (14 patients) in the group treated by RFA-SS and 59.9% (9 patients) in the group treated by RT-SS (p = 0.048). Although recurrent pain was documented more frequently after RT-SS (26.6%) than after RFA-SS (6.7%) the difference did not reach statistical significance. The morbidity related to RT-SS did not significantly differ when the treatment was associated with RFA. We observed a reduction in blood transfusion, as 3 patients in the RT-SS group required a blood transfusion, versus none in the RFA-SS group. Our results suggest that RFA-SS is safe and is more effective than RT-SS; furthermore, RFA may become an option for patients with metastases of the long bones to prevent tumour dissemination and reduce intraoperative blood loss. The findings described here should serve as a framework around which to design future clinical trials.

  5. Local ablative therapies in HCC: percutaneous ethanol injection and radiofrequency ablation.

    PubMed

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

    2009-01-01

    Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy. Surgery and transarterial chemoembolization have for many years dominated the local treatment of HCC. The introduction of image-guided percutaneous techniques for local tumor ablation changed the treatment of liver cancer. Percutaneous ethanol injection (PEI) and radiofrequency ablation (RFA) have both successfully been employed in the treatment of HCC. In current guidelines both techniques are recommended as standard therapy in limited liver cancer. From the current literature both techniques have to be considered safe and effective in the treatment of HCC. Several randomized trials showed RFA to be superior to PEI for treating small HCC. Moreover, several studies analyzed survival after PEI or RFA in comparison with surgery, proving interventional therapy to be a serious competitor of resection. With introduction of combined interventional therapies including transarterial chemoembolization, PEI and RFA survival was improved further. In this article, we provide an insight into the technical basics of PEI and RFA and review the clinical results and indications of these interventional techniques in the treatment of HCC.

  6. Radiofrequency energy ablation in a child with an implanted vagus nerve stimulator.

    PubMed

    Radolec, Mackenzy M; Beerman, Lee B; Arora, Gaurav

    2015-10-01

    An 8-year-old girl with supraventricular tachycardia and an implanted vagus nerve stimulator underwent radiofrequency ablation of her supraventricular tachycardia substrate. No known literature exists addressing the potential interaction of these two technologies, although there are reported cases of interaction between radiofrequency and other implanted stimulating devices such as pacemakers. The procedure was performed successfully without observed interaction, and the patient's family reported no significant change in frequency of seizure control.

  7. Stereotactic radiofrequency ablation for the treatment of gelastic seizures associated with hypothalamic hamartoma. Case report.

    PubMed

    Parrent, A G

    1999-11-01

    The author presents the case of a patient with gelastic seizures associated with a hypothalamic hamartoma, in whom partial resection of the hamartoma followed by temporal lobectomy and orbitofrontal corticectomy failed to reduce the seizures. Subsequent stereotactic radiofrequency ablation of the hamartoma resulted in progressive improvement in the seizure disorder during a 28-month follow-up period. There is support in the literature for the concept that gelastic seizures originate directly from the hamartoma; however, direct surgical approaches to these lesions pose significant risks. It is proposed that the technique of radiofrequency ablation provides a minimally invasive, low-risk approach for the treatment of hypothalamic hamartomas.

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

    SciTech Connect

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

    2006-06-15

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

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

    SciTech Connect

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

    2009-01-15

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

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

    PubMed

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

    2015-01-01

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

  11. Radiofrequency ablation of spinal osteoid osteoma: a prospective study.

    PubMed

    Faddoul, Joe; Faddoul, Yara; Kobaiter-Maarrawi, Sandra; Moussa, Ronald; Rizk, Tony; Nohra, Georges; Okais, Nabil; Samaha, Elie; Maarrawi, Joseph

    2017-03-01

    OBJECTIVE Surgery has been considered the standard treatment for spinal osteoid osteomas that are refractory to analgesic agents. Radiofrequency ablation (RFA) is a less invasive technique with established efficiency for the treatment of peripheral osteoid osteomas. The main objectives of this study are to evaluate the safety of RFA based on the results of a previous experimental study in rats conducted in the authors' laboratory and to identify its short- and long-term efficiency in the treatment of spinal osteoid osteomas. METHODS Between March 2009 and July 2016, 8 consecutive patients with spinal osteoid osteomas were enrolled in the study and underwent 9 CT-guided RFA procedures. All patients presented with spinal pain (median preoperative visual analog scale [VAS] score 7.55, range 6-8.8) predominantly during the night, and they all had normal neurological examination results before the procedure. Pain (according to the VAS score) and neurological status were reassessed immediately before discharge, with further follow-up at 1, 6, and 12 months after the procedure. At the final follow-up, VAS score, neurological examination, patient satisfaction, and a radiological control (CT scan) were documented (median 48 months, range 12-84 months). VAS scores before and after the procedure were compared during the 3 days before surgery (D0), on the day of the surgery, Day 1 (D1), and at the final follow-up. RESULTS No neurological deficit was documented following the procedure or at the final follow-up. A statistically significant reduction in the VAS score was observed on Day 1 (mean 2.56 ± 0.68, p = 0.005) compared with D0. At the final follow-up, all patients reported a VAS score of 0 and a satisfaction rate of 100%. Only 1 patient had recurrent symptoms (pain, VAS score 8.1) 6 months after the initial RFA. A second procedure was performed, and the patient was subsequently symptom free at the final follow-up. CT scanning performed in all patients (12-84 months post

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

    PubMed Central

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

    2015-01-01

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

  13. CT-Guided Radiofrequency Ablation of a Pulmonary Metastasis Followed by Surgical Resection

    SciTech Connect

    Steinke, Karin; Habicht, James M.; Thomsen, Sharon; Soler, Markus; Jacob, Augustinus L.

    2002-12-15

    Outpatient CT-guided radiofrequency ablation (RFA)of a pulmonary metastasis followed by surgical resection and histopathological analysis was performed in a 72-year-old lady suffering from a peritoneal leiomyosarcoma. Histological workup 3 weeks post-ablation showed complete devitalization of the metastasis. This case report demonstrates that complete thermal destruction of a pulmonary metastasis by percutaneous image-guided RFA is possible.

  14. Early Diagnosis of Intrahepatic Pseudoaneurysm during Radiofrequency Ablation using Contrast-Enhanced Ultrasound

    PubMed Central

    Kumar, S Krishna; Oon, Ong Keh; Horgan, Paul; Leen, Edward

    2015-01-01

    Radiofrequency ablation is one of the more established forms of local treatment in patients with unresectable tumours, including colorectal hepatic metastases. Complications associated with this method of intervention include thermal and mechanical injuries, including vascular insults resulting in haemorrhage or pseudoaneurysm formation. This is the first case demonstrating the detection of post-ablation acute pseudoaneurysm formation identified on the table using contrast-enhanced ultrasound (CEUS) and the subsequent successful management. PMID:28223887

  15. Management of complications following radiofrequency ablation of a pedicle osteoid osteoma.

    PubMed

    Owen, Joseph W; Bridwell, Keith H; Gilula, Louis A

    2014-06-01

    Radiofrequency ablation (RFA) has become an accepted first-line treatment for osteoid osteomas. Ablation of spinal osteoid osteomas has presented a particular challenge because of their proximity to delicate neural structures. Although many case series have reported multiple successfully treated spinal osteoid osteomas, there are no reports of thermal injury or insufficiency fracture associated with RFA of spinal osteoid osteomas. We report the management of complications that result from treating a spinal osteoid osteoma within a pedicle.

  16. Impact of Laser Fiber Design on Outcome of Endovenous Ablation of Lower-Extremity Varicose Veins: Results from a Single Practice

    SciTech Connect

    Prince, Ethan A. Soares, Gregory M.; Silva, MaryLou; Taner, Anil; Ahn, SunHo; Dubel, Gregory J.; Jay, Bryan S.

    2011-06-15

    The design of laser fibers used for endovenous laser ablation (EVLA) in the management of lower-extremity varicose vein disease may affect treatment success. The purpose of this investigation is to report our experience using the gold-tip NeverTouch VenaCure laser fiber (AngioDynamics, Queensbury, NY) and to compare that to our experience with standard bare-tip fibers. A retrospective chart review of 363 consecutive EVLA treatments using the gold-tip laser fiber was performed. Demographic data including patient age, sex, history of previous varicose vein stripping, vein identity, laterality, treatment length, total applied energy in joules (J), use of adjuvant sclerotherapy and ambulatory phlebectomy, treatment-related complications, and treatment failure, which was defined as recanalization of any portion of the treated vein during follow-up as assessed by duplex ultrasound examination-were entered into a spreadsheet. These data were compared with a control group of 471 EVLA treatments performed with a standard bare-tip laser fiber. Data were analyzed using independent-samples Student's t test, chi-square test, and multivariate analysis. Demographic data were similar between the two groups. Treatments with the gold-tip fiber had a failure rate of 11.1%, whereas treatment with a bare-tip fiber had a failure rate of 2.3% during a similar follow-up period. This difference was highly statistically significant (p < 0.0001). Multivariate analysis showed fiber type as the most significant factor associated with treatment failure. We conclude that laser fiber design has a significant effect on treatment success in the performance of EVLA.

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

    NASA Astrophysics Data System (ADS)

    Patel, Vipul; Thaly, Rahul; Shah, Ketul

    2007-02-01

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

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

    SciTech Connect

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

    2011-06-15

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

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

    SciTech Connect

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

    2011-02-15

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

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

    SciTech Connect

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

    1991-08-01

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

  1. Extending the Frontiers Beyond Thermal Ablation by Radiofrequency Ablation: SBRT, Brachytherapy, SIRT (Radioembolization).

    PubMed

    Hass, Peter; Mohnike, Konrad

    2014-08-01

    Metastatic spread of the primary is still defined as the systemic stage of disease in treatment guidelines for various solid tumors. This definition is the rationale for systemic therapy. Interestingly and despite the concept of systemic involvement, surgical resection as a local treatment has proven to yield long-term outcomes in a subset of patients with limited metastatic disease, supporting the concept of oligometastatic disease. Radiofrequency ablation has yielded favorable outcomes in patients with hepatocellular carcinoma and colorectal metastases, and some studies indicate its prognostic potential in combined treatments with systemic therapies. However, some significant technical limitations apply, such as size limitation, heat sink effects, and unpredictable heat distribution to adjacent risk structures. Interventional and non-invasive radiotherapeutic techniques may overcome these limitations, expanding the options for oligometastatic patients and cytoreductive concepts. Current data suggest very high local control rates even in large tumors at any given location in the human body. The article focusses on the characteristics and possibilities of stereotactic body radiation therapy, interstitial high-dose-rate brachytherapy, and Yttrium-90 radioembolization. In this article, we discuss the differences of the technical preferences as well as their impact on indications. Current data is presented and discussed with a focus on application in oligometastatic or cytoreductive concepts in different tumor biologies.

  2. Extending the Frontiers Beyond Thermal Ablation by Radiofrequency Ablation: SBRT, Brachytherapy, SIRT (Radioembolization)

    PubMed Central

    Hass, Peter; Mohnike, Konrad

    2014-01-01

    Summary Metastatic spread of the primary is still defined as the systemic stage of disease in treatment guidelines for various solid tumors. This definition is the rationale for systemic therapy. Interestingly and despite the concept of systemic involvement, surgical resection as a local treatment has proven to yield long-term outcomes in a subset of patients with limited metastatic disease, supporting the concept of oligometastatic disease. Radiofrequency ablation has yielded favorable outcomes in patients with hepatocellular carcinoma and colorectal metastases, and some studies indicate its prognostic potential in combined treatments with systemic therapies. However, some significant technical limitations apply, such as size limitation, heat sink effects, and unpredictable heat distribution to adjacent risk structures. Interventional and non-invasive radiotherapeutic techniques may overcome these limitations, expanding the options for oligometastatic patients and cytoreductive concepts. Current data suggest very high local control rates even in large tumors at any given location in the human body. The article focusses on the characteristics and possibilities of stereotactic body radiation therapy, interstitial high-dose-rate brachytherapy, and Yttrium-90 radioembolization. In this article, we discuss the differences of the technical preferences as well as their impact on indications. Current data is presented and discussed with a focus on application in oligometastatic or cytoreductive concepts in different tumor biologies. PMID:26288597

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

    PubMed

    Boronyak, Steven M; Merryman, W David

    2014-03-21

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

  4. Subclinical Breast Cancer: Minimally Invasive Approaches. Our Experience with Percutaneous Radiofrequency Ablation vs. Cryotherapy

    PubMed Central

    Manenti, Guglielmo; Scarano, Angela L.; Pistolese, Chiara A.; Perretta, Tommaso; Bonanno, Elena; Orlandi, Augusto; Simonetti, Giovanni

    2013-01-01

    Summary Background The aim of this study was to compare the efficacy of radiofrequency ablation vs. cryoablation in the treatment of early breast cancer. Patients and Methods 80 women (mean age 73 ± 5 years) with early breast cancer were retrospectively evaluated. 40 patients underwent cryoablation and 40 patients underwent radiofrequency ablation, both with sentinel lymph node excision. Tumor volume and histopatological data were compared by means of postprocedural 3.0-T magnetic resonance imaging (MRI). 30–45 days after the percutaneous ablation, all patients underwent surgical resection of the tumor. The mean follow-up was 18 months without any local recurrences. Results Both techniques allow good correlation with histopathological data. In 75 patients (93.8%) we observed complete necrosis; in 5 cases there was residual disease in the postprocedural MRI and postoperative histological examination. There was a good correlation between MRI volume and histologic samples. Cosmetic results were good in all patients but 2. Conclusion Both percutaneous radiofrequency ablation and cryotherapy are minimally invasive techniques with a good clinical and cosmetic outcome in selected cases. MRI examination is an ideal method to assess breast neoplasms in terms of quality and quantity as well as residual tumor extent after percutaneous ablation. Cryotherapy is the preferred method because of the analgesic effect of freezing with better patients compliance. PMID:24415989

  5. Outcomes of Radiofrequency Ablation for Dysplastic Barrett's Esophagus: A Comprehensive Review

    PubMed Central

    Iabichino, Giuseppe; Arena, Monica; Consolo, Pierluigi; Morace, Carmela; Opocher, Enrico; Mangiavillano, Benedetto

    2016-01-01

    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. PMID:28070182

  6. Nonfluoroscopic Imaging as Guidance for Radiofrequency Ablation of Atrioventricular Nodal Reentrant Tachycardia after Mustard Repair

    PubMed Central

    Nguyen, Dinh Q.; Sobczak, Henrik; Brandts, Bodo

    2017-01-01

    Most tachycardias in the pulmonary venous atrium are inaccessible by direct means and require either a retrograde approach or a transseptal approach for ablation. We present a case in which successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia was accomplished via a retrograde transaortic approach guided by nonfluoroscopic mapping with use of the NavX™ mapping system. The patient was a 49-year-old woman who at the age of 4 years had undergone Mustard repair for complete dextrotransposition of the great arteries. Three-dimensional reconstructions of the ascending aorta, right ventricle, systemic venous atrium, left ventricle, and superior vena cava–inferior vena cava baffle complex were created, and the left-sided His bundle was marked. After a failed attempt at ablation from the systemic venous side, we eliminated the atrioventricular nodal reentrant tachycardia by ablation from the pulmonary venous side. This case is, to our knowledge, the first report of successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia after Mustard repair for this congenital cardiac malformation in which ablation was guided by 3-dimensional nonfluoroscopic imaging. This imaging technique enabled accurate anatomic location of the ablation catheters in relation to the His bundle marked from the systemic venous side. PMID:28265215

  7. Acute myocardial infarction after radiofrequency catheter ablation of typical atrial flutter.

    PubMed

    Yune, Sehyo; Lee, Woo Joo; Hwang, Ji-won; Kim, Eun; Ha, Jung Min; Kim, June Soo

    2014-02-01

    A 53-yr-old man underwent radiofrequency ablation to treat persistent atrial flutter. After the procedure, the chest pain was getting worse, and the electrocardiogram showed ST-segment elevation in inferior leads with reciprocal changes. Immediate coronary angiography showed total occlusion with thrombi at the distal portion of the right coronary artery, which was very close to the ablation site. Intervention with thrombus aspiration and balloon dilatation was successful, and the patient recovered without any kind of sequelae. Although the exact mechanism is obscure, the most likely explanation is a thermal injury to the vascular wall that ruptured into the lumen and formed thrombus. Vasospasm and thromboembolism can also be other possibilities. This case raise the alarm to cardiologists who perform radiofrequency ablation to treat various kinds of cardiac arrhythmias, in that myocardial infarction has been rarely considered one of the complications.

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

    SciTech Connect

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

    2013-06-15

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

  9. Laparoscopic vs computerized tomography-guided radiofrequency ablation for large hepatic hemangiomas abutting the diaphragm

    PubMed Central

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

    2015-01-01

    AIM: To compare safety and therapeutic efficacy of laparoscopic radiofrequency (RF) ablation vs computed tomography (CT)-guided RF ablation for large hepatic hemangiomas abutting the diaphragm. METHODS: We retrospectively reviewed our sequential experience of treating 51 large hepatic hemangiomas abutting the diaphragm in 51 patients by CT-guided or laparoscopic RF ablation due to either the presence of symptoms and/or the enlargement of hemangioma. Altogether, 24 hemangiomas were ablated via a CT-guided percutaneous approach (CT-guided ablation group), and 27 hemangiomas were treated via a laparoscopic approach (laparoscopic ablation group). RESULTS: The mean diameter of the 51 hemangiomas was 9.6 ± 1.8 cm (range, 6.0-12.0 cm). There was no difference in the diameter of hemangiomas between the two groups (P > 0.05). RF ablation was performed successfully in all patients. There was no difference in ablation times between groups (P > 0.05). There were 23 thoracic complications in 17 patients: 15 (62.5%, 15/24) in the CT-guided ablation group and 2 (7.4%, 2/27) in the laparoscopic ablation group (P < 0.05). According to the Dindo-Clavien classification, two complications (pleural effusion and diaphragmatic rupture grade III) were major in two patients. All others were minor (grade I). Both major complications occurred in the CT-guided ablation group. The minor complications were treated successfully with conservative measures, and the two major complications underwent treatment by chest tube drainage and thoracoscopic surgery, respectively. Complete ablation was achieved in 91.7% (22/24) and 96.3% (26/27) in the CT-guided and the laparoscopic ablation groups, respectively (P > 0.05). CONCLUSION: Laparoscopic RF ablation therapy should be used as the first-line treatment option for large hepatic hemangiomas abutting the diaphragm. It avoids thermal injury to the diaphragm and reduces thoracic complications. PMID:26019459

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

    PubMed

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

    2015-03-01

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

  11. Tracked 3D ultrasound in radio-frequency liver ablation

    NASA Astrophysics Data System (ADS)

    Boctor, Emad M.; Fichtinger, Gabor; Taylor, Russell H.; Choti, Michael A.

    2003-05-01

    Recent studies have shown that radio frequency (RF) ablation is a simple, safe and potentially effective treatment for selected patients with liver metastases. Despite all recent therapeutic advancements, however, intra-procedural target localization and precise and consistent placement of the tissue ablator device are still unsolved problems. Various imaging modalities, including ultrasound (US) and computed tomography (CT) have been tried as guidance modalities. Transcutaneous US imaging, due to its real-time nature, may be beneficial in many cases, but unfortunately, fails to adequately visualize the tumor in many cases. Intraoperative or laparoscopic US, on the other hand, provides improved visualization and target imaging. This paper describes a system for computer-assisted RF ablation of liver tumors, combining navigational tracking of a conventional imaging ultrasound probe to produce 3D ultrasound imaging with a tracked RF ablation device supported by a passive mechanical arm and spatially registered to the ultrasound volume.

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

    SciTech Connect

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

    2015-10-15

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

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

    SciTech Connect

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

    2010-02-15

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

  14. [Endocavitary ablation for arrhythmias. New modalities of radiofrequency applications. New energy types].

    PubMed

    Cauchemez, B; Lavergne, Th; Extramiana, F; Siliste, C; Leenhardt, A; Coumel, Ph

    2002-04-01

    Radiofrequency remains the reference energy type for catheter ablation of rhythm disorders. In the classic indications, which are atrial flutter or tachycardia, nodal re-entry and Wolff-Parkinson-White syndrome, this energy source has the best cost-efficiency-safety ratio, subject to strict conditions of use. Some new modalities of application have further improved performance, especially active irrigation of the electrode which allows induction of deeper lesions which is very useful for the ablation of difficult atrial flutters, epicardial fascicles of Kent and ischaemic ventricular tachycardias. The only emerging alternative energy type, in the framework of classical ablation, is cold, for which the principal advantages are the homogenous and slightly thrombogenic character for the lesion involved, and the possibility of reversible applications tests which are especially useful in the ablation of structures at risk. The situation is more open-ended concerning research on ablation for atrial fibrillation or the so-called new energy types, such as ultrasound and laser, whilst recognising a renewal in interest, especially for circumferential ablation of the pulmonary veins to isolate the ectopic venous foci. Mechanical energy such as luminous energy is emitted across a catheter balloon deployed at the orifice of the vein, perpendicular to its axis, aiming to reach a continuous circumferential lesion with a minimum of applications. Equally radiofrequency has been undergoing significant evolution for this application, such as by the development of porous catheter balloons with a liquid electrode, as well as by the development of deployable circumferential catheters. Ablation is use for atrial fibrillation, by endocavity atrial segmentation remains a field of research in which radiofrequency retains an important place. It is delivered via multi-electrode catheters according to the new application modalities, either pulsed or by phase interval, which secure better

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

    PubMed Central

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

    2015-01-01

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

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

    SciTech Connect

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

    2013-06-15

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

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

    SciTech Connect

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

    2013-06-15

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

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

    SciTech Connect

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

    2010-08-15

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

  19. Towards patient-specific modelling of lesion formation during radiofrequency catheter ablation for atrial fibrillation

    PubMed Central

    Soor, Navjeevan; Morgan, Ross; Varela, Marta; Aslanidi, Oleg V.

    2017-01-01

    Radiofrequency catheter ablation procedures are a first-line method of clinical treatment for atrial fibrillation. However, they suffer from suboptimal success rates and are also prone to potentially serious adverse effects. These limitations can be at least partially attributed to the inter- and intra- patient variations in atrial wall thickness, and could be mitigated by patient-specific approaches to the procedure. In this study, a modelling approach to optimising ablation procedures in subject-specific 3D atrial geometries was applied. The approach enabled the evaluation of optimal ablation times to create lesions for a given wall thickness measured from MRI. A nonliner relationship was revealed between the thickness and catheter contact time required for fully transmural lesions. Hence, our approach based on MRI reconstruction of the atrial wall combined with subject-specific modelling of ablation can provide useful information for improving clinical procedures.

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

    PubMed

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

    1998-09-01

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

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

    SciTech Connect

    Gananadha, Sivakumar Morris, David Lawson

    2004-08-15

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

  2. Restoration of Atrial Mechanical Function after Successful Radio-Frequency Catheter Ablation of Atrial Flutter

    PubMed Central

    Rhee, Kyoung-Suk; Kang, Duk-Hyun; Song, Jae-Kwan; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho

    2001-01-01

    Background: Atrial mechanical dysfunction and its recovery time course after successful radiofrequency ablation of chronic atrial flutter (AFL) has been largely unknown. We serially evaluated left atrial function by echocardiography after successful ablation of chronic atrial flutter. Methods: In 13 patients with chronic AFL, mitral E wave A wave, and the ratio of A/E velocity were measured at 1 day, 1 month, 3 months and 6–12 months after successful radiofrequency (RF) ablation. Doppler tissue imaging (DTI) technique was also used to avoid load-dependent variation in the flow velocity pattern. Results: Left atrial mechanical function, assessed by A wave velocity and the annular motion, was depressed at 1 day, but improved significantly at 1 month and maintained through 6–12 months after the ablation. Left atrial size did not change significantly. Conclusion: Left atrial mechanical function was depressed immediately after successful RF ablation of chronic AFL, but it improved significantly after 1 month and was maintained over one year. PMID:11590904

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

    SciTech Connect

    Boone, Judith; Bex, Axel; Prevoo, Warner

    2012-06-15

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

  4. Ultrasound simulation of real-time temperature estimation during radiofrequency ablation using finite element models.

    PubMed

    Daniels, M J; Jiang, J; Varghese, T

    2008-03-01

    Radiofrequency ablation is the most common minimally invasive therapy used in the United States to treat hepatocellular carcinoma and liver metastases. The ability to perform real-time temperature imaging while a patient is undergoing ablation therapy may help reduce the high recurrence rates following ablation therapy. Ultrasound echo signals undergo time shifts with increasing temperature due to sound speed and thermal expansion, which are tracked using both 1D cross correlation and 2D block matching based speckle tracking methods. In this paper, we present a quantitative evaluation of the accuracy and precision of temperature estimation using the above algorithms on both simulated and experimental data. A finite element analysis simulation of radiofrequency ablation of hepatic tissue was developed. Finite element analysis provides a method to obtain the exact temperature distribution along with a mapping of the tissue displacement due to thermal expansion. These local displacement maps were combined with the displacement due to speed of sound changes and utilized to generate ultrasound radiofrequency frames at specified time increments over the entire ablation procedure. These echo signals provide an ideal test-bed to evaluate the performance of both speckle tracking methods, since the estimated temperature results can be compared directly to the exact finite element solution. Our results indicate that the 1D cross-correlation (CC) method underestimates the cumulative displacement by 0.20mm, while the underestimation with 2D block matching (BM) is about 0.14 mm after 360 s of ablation. The 1D method also overestimates the size of the ablated region by 5.4% when compared to 2.4% with the 2D method after 720 s of ablation. Hence 2D block matching provides better tracking of temperature variations when compared to the 1D cross-correlation method over the entire duration of the ablation procedure. In addition, results obtained using 1D cross-correlation diverge from

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

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

    SciTech Connect

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

    2011-02-15

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

  7. [Radiofrequency ablation of atrioventricular conduction during the 5th month of pregnancy].

    PubMed

    Gras, D; Mabo, P; Kermarrec, A; Bazin, P; Varin, C; Daubert, C

    1992-12-01

    The authors report the case of radiofrequency ablation of atrioventricular conduction in a 5 months pregnant woman who had hypertrophic cardiomyopathy. The indication of this procedure was a poorly tolerated resistant supraventricular tachycardia with foetal distress. A dual-chamber rate-assisted pacemaker programmed in the VVIR mode was implanted during the same procedure normally, with normal delivery of a healthy child at 8 months' gestation.

  8. Laser ablation of liver tumors: An ancillary technique, or an alternative to radiofrequency and microwave?

    PubMed Central

    Sartori, Sergio; Di Vece, Francesca; Ermili, Francesca; Tombesi, Paola

    2017-01-01

    Radiofrequency ablation (RFA) is currently the most popular and used ablation modality for the treatment of non surgical patients with primary and secondary liver tumors, but in the last years microwave ablation (MWA) is being technically improved and widely rediscovered for clinical use. Laser thermal ablation (LTA) is by far less investigated and used than RFA and MWA, but the available data on its effectiveness and safety are quite good and comparable to those of RFA and MWA. All the three hyperthermia-based ablative techniques, when performed by skilled operators, can successfully treat all liver tumors eligible for thermal ablation, and to date in most centers of interventional oncology or interventional radiology the choice of the technique usually depends on the physician’s preference and experience, or technical availability. However, RFA, MWA, and LTA have peculiar advantages and limitations that can make each of them more suitable than the other ones to treat patients and tumors with different characteristics. When all the three thermal ablation techniques are available, the choice among RFA, MWA, and LTA should be guided by their advantages and disadvantages, number, size, and location of the liver nodules, and cost-saving considerations, in order to give patients the best treatment option.

  9. Rupture of benign thyroid tumors after radio-frequency ablation.

    PubMed

    Shin, J H; Jung, S L; Baek, J H; Kim, J-H

    2011-12-01

    Rupture of benign thyroid tumors after RFA is very rare. We experienced 6 cases in 4 institutions. All patients presented with abrupt neck swelling and pain between 9 and 60 days after RFA. Imaging and clinical findings of the ruptured tumors were anterior subcapsular location, mixed composition, large size, and repeated ablations. Conservative treatment was sufficient in 3 cases, whereas surgical management was required in 3.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-04-01

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

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

    SciTech Connect

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

    2009-01-15

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

  13. CT-guided radiofrequency ablation in patients with hepatic metastases from breast cancer.

    PubMed

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

    2009-01-01

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

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

    PubMed

    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.

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

    SciTech Connect

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

    2012-08-15

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

  16. Pathological proof of cellular death in radiofrequency ablation therapy and correlation with flash echo imaging--an experiment study.

    PubMed

    Fujiki, Kei

    2004-01-01

    The aims of this study were to clarify the geographic distribution of complete cell death in the radiofrequency ablated area in a porcine liver experiment, and to evaluate the efficacy of ultrasonography using contrast media in detecting the area of Radiofrequency-induced cell death. Radiofrequency ablation was performed at 3 sites in each liver in seven swine with a RF2000TM radiofrequency generator using an expandable type needle electrode. The ablation area was investigated histologically by Hematoxylin-Eosin staining and NADH staining. The area of radiofrequency-induced cell death was correlated to the ultrasonographic findings using contrast media, by means of contrast harmonic imaging, flash echo imaging-subtraction and flash echo imaging-power Doppler. The ablation area showed three distinct regions. Although the HE staining did not indicate necrosis, the NADH staining showed a complete loss of cellular activity in the inner and middle layers of the ablation area. However, in the outer layer cells displaying cellular integrity were intermingled with the necrotic cells, indicating that some of the cells in this layer had a chance to survive. Further, in some cases the outer layer of the ablated area had irregular margins. The flash-echo power-doppler images were accurately correlated in size and shape to the pathologically proved region of complete cell death in the radiofrequency-induced lesions. In the marginal part of the radiofrequency ablation area, cell death was incomplete. Flash echo imaging-power doppler was a useful and sensitive real time imaging technique for accurate evaluation of the region of complete cell death.

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

    PubMed

    Benito Bartolomé, F; Sánchez Fernández-Bernal, C

    2001-08-01

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

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

    SciTech Connect

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

    2011-04-15

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

  19. CT Mapping of the Distribution of Saline During Radiofrequency Ablation with Perfusion Electrodes

    SciTech Connect

    Gillams, A.R. Lees, W.R.

    2005-05-15

    Purpose. During radiofrequency (RF) ablation, adjunctive saline increases the size of the ablation zone and therefore electrodes that simultaneously deliver current and saline have been developed, but the addition of saline also results in an irregular ablation zone. Our aim was to study the distribution of saline during RF ablation. Methods. Four patients were treated: 3 with liver metastases and 1 with hepatocellular carcinoma (HCC). Two different perfusion electrodes were used: a high-perfusion-rate, straight electrode (Berchtold, Germany) and a low-perfusion-rate, expandable electrode (RITA Medical Systems, USA). The saline perfusate was doped with non-ionic contrast medium to render it visible on CT and the electrical conductivity was measured. CT scans were obtained of each electrode position prior to ablation and repeated after ablation. Contrast-enhanced CT was performed 18-24 hr later to demonstrate the ablation zone. All treatments were carried out according to the manufacturer's recommended protocol. Results. The addition of a small quantity of non-ionic contrast did not alter the electrical conductivity of the saline. Contrast-doped saline extravasated beyond the tumor in all 3 patients with metastases but was limited in the patient with HCC. In some areas where saline had extravasated there was reduced enhancement on contrast-enhanced CT consistent with tissue ablation. One patient treated with the high-perfusion-rate system sustained a jejunal perforation requiring surgery. Conclusion. Saline can extravasate beyond the tumor and with the high-perfusion-rate system this resulted in an undesirable extension of the ablation zone and a complication.

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

    PubMed Central

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

    2016-01-01

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

  1. Local tumor progression patterns after radiofrequency ablation of colorectal cancer liver metastases

    PubMed Central

    Napoleone, Marc; Kielar, Ania Z.; Hibbert, Rebecca; Saif, Sameh; Kwan, Benjamin Y.M.

    2016-01-01

    PURPOSE We aimed to evaluate patterns of local tumor progression (LTP) after radiofrequency ablation (RF ablation) of colorectal cancer liver metastases (CRCLM) and to highlight the percentage of LTP not attributable to lesion size or RF ablation procedure-related factors (heat sink or insufficient ablation margin). METHODS CRCLM treated by RF ablation at a single tertiary care center from 2004–2012, with a minimum of six months of postprocedure follow-up, were included in this retrospective study. LTP morphology was classified as focal nodular (<90° of ablation margin), circumferential (>270°), or crescentic (90°–270°). Initial metastasis size, minimum ablation margin size, morphology of LTP, presence of a heat sink, and time to progression were recorded independently by two radiologists. RESULTS Thirty-two of 127 RF ablation treated metastases (25%) with a mean size of 23 mm (standard deviation 12 mm) exhibited LTP. Fifteen of 32 LTPs (47%) were classified as focal nodular, with seven having no procedure-related factor to explain recurrence. Ten of 32 LTPs (31%) were circumferential, with four having no procedure-related factor to explain recurrence. Seven of 32 LTPs (22%) were crescentic, with two having no procedure-related factor to explain recurrence. Of the 13 lesions without any obvious procedure-related reason for LTP, six (46%) were <3 cm in size. CONCLUSION Although LTP in RF ablation treated CRCLM can often be explained by procedure-related factors or size of the lesion, in this study up to six (5%) of the CRCLM we treated showed LTP without any reasonable cause. PMID:27705879

  2. Increasing power versus duration for radiofrequency ablation with a high superfusate flow: implications for pulmonary vein ablation?

    PubMed

    Guy, Duncan J R; Boyd, Anita; Thomas, Stuart P; Ross, David L

    2003-06-01

    Radiofrequency (RF) ablation of pulmonary veins (PVs) is a new treatment for atrial fibrillation. Low energy ablation is usually used for this procedure. The effect of superfusate flow on lesion formation in this setting has not been studied previously. We examined lesion dimensions and intramural temperatures with varying powers and duration of RF application in this high flow environment. Ablation of fresh bovine hearts was performed with a 4-mm tip RF catheter in temperature control mode, target temperature 50 degrees C. At power levels of 20 W, 30 W, 40 W, and 50 W, effects of PV flow (no flow or 1 L/min) and 60- and 120-second durations were tested. Tissue temperatures were recorded at depths of 1, 4, 7, and 10 mm. Without flow, no lesions were created. The lowest power setting for lesion creation was 30 W at 60 seconds and 20 W at 120 seconds. Increasing power from 30 W to 50 W for 60 seconds increased lesion depth 0.7 mm (SE 0.3), P = 0.03 and 2.5 mm (SE 0.6), P = 0.003, at 120 seconds. Increasing RF application duration from 60 to 120 seconds increased depth for 30 W by 0.9 mm (SE 0.5), P = NS, 40 W 1.7 mm (SE 0.4), P = 0.002, and 50 W 2.6 mm (SE 0.5), P < 0.001. Power of 50 W for 60 seconds and >30 W for 120 seconds created lesions deeper than the wall thickness of a PV. Flow is necessary for creation of lesions with low power, low tip temperature RF ablation. When a resistant site to ablation is encountered, increasing duration of ablation is best for increasing lesion depth. Higher power has the potential to create lesions deeper than the PV wall and may increase the risk of complications.

  3. No-Touch Radiofrequency Ablation: A Comparison of Switching Bipolar and Switching Monopolar Ablation in Ex Vivo Bovine Liver

    PubMed Central

    Chang, Won; Lee, Sang Min; Han, Joon Koo

    2017-01-01

    Objective 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. Materials and Methods 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. Results 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. Conclusion 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. PMID:28246508

  4. Percutaneous radiofrequency ablation of benign thyroid nodules assisted by a virtual needle tracking system.

    PubMed

    Turtulici, Giovanni; Orlandi, Davide; Corazza, Angelo; Sartoris, Riccardo; Derchi, Lorenzo Egildo; Silvestri, Enzo; Baek, Jung Hwan

    2014-07-01

    Our aim was to assess the feasibility and outcome of ultrasound (US)-guided percutaneous radiofrequency (RF) ablation of benign thyroid nodules assisted by a real-time virtual needle tracking (VT) system. Forty-five patients (34 females, mean age ± standard deviation (SD): 44 ± 16 y, range: 29-68 y) with 45 benign non-functioning thyroid nodules (mean volume ± SD: 13.5 ± 6.7 mL, range: 12-22 mL) underwent VT-assisted US-guided RF ablation. Nodule volume was evaluated before treatment and during 6-mo of follow-up. Complication rates and patient satisfaction after treatment were also evaluated. By use of the VT system, the tip of the RF electrode was identified during all ablation procedures. The overall mean volume reduction and complication rate were 72.6 ± 11.3% and 2.5%, respectively. Overall satisfaction at the 6-mo follow-up was rated by patients as positive in 42 cases (93%). The VT system could be useful in thyroid nodule ablation procedures because it is able to track the RF electrode tip even when the tip is obscured by the bubbles produced by the ablative process. VT-assisted RF ablation can be a tolerable, non-surgical treatment for patients with benign non-functioning thyroid nodules.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

    Li, Qiang; Chen, Pin-Yu; Wang, Chiao-Yin; Liu, Hao-Li; Teng, Jianfu

    2014-01-01

    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. PMID:24971347

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

    SciTech Connect

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

    2010-10-15

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

  8. Varicose vein - noninvasive treatment

    MedlinePlus

    Sclerotherapy; Laser therapy - varicose veins; Radiofrequency vein ablation; Endovenous thermal ablation; Ambulatory phlebectomy; Transilluminated power phlebotomy; Endovenous laser ablation; Varicose vein ...

  9. Unguarded tricuspid orifice with pulmonary atresia: successful radiofrequency ablation of an accessory pathway in an infant

    PubMed Central

    Magee, A.; Rosenthal, E.; Bostock, J.; Gill, J.

    1998-01-01

    A male infant with the rare lesion of unguarded tricuspid orifice in the setting of pulmonary valve atresia, intact ventricular septum, and a hypoplastic right ventricle is described. The patient presented with cyanosis at 1 day old; transcutaneous oxygen saturations were between 20% and 30% in room air, and 60% in 100% inspired oxygen. Pre-excitation was found incidentally on the ECG and the potential for rapid antegrade conduction of atrial tachyarrhythmias, after eventual extended palliation with the Fontan procedure, was demonstrated at electrophysiological study. By 11 months old the patient was becoming increasingly cyanosed and interim palliation with a bidirectional cavopulmonary shunt was proposed. Successful radiofrequency ablation of the accessory pathway was performed before bidirectional cavopulmonary shunt, which would have prevented access to the heart via the superior vena cava. Difficulty with femoral venous access because of previous occlusion of a femoral vein was overcome by the use of 2 F pacing electrodes and a 5 F ablation catheter.

 Keywords: radiofrequency ablation;  accessory pathway;  unguarded tricuspid orifice PMID:9505931

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

    PubMed Central

    Gaidhane, Monica; Smith, Ioana; Ellen, Kristi; Gatesman, Jeremy; Habib, Nagy; Foley, Patricia; Moskaluk, Christopher; Kahaleh, Michel

    2012-01-01

    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. PMID:23049547

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

    Berjano, Enrique J

    2006-01-01

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

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

    SciTech Connect

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

    2013-02-15

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

  14. Effect of Ultrasound-Guided Radiofrequency Ablation in Incompletely Treated Hepatocellular Carcinoma after Transcatheter Arterial Chemoembolization

    PubMed Central

    Chang, Nam Kyu; Kim, Jin Woong; Kim, Hyung Jun; Jeong, Yong Yeon; Heo, Suk Hee; Kim, Jae Kyu; Kang, Heoung Keun

    2012-01-01

    Objective To evaluate the effectiveness of ultrasound-guided radiofrequency (RF) ablation in patients with incompletely treated hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) and to evaluate possible prognostic factors for this therapy. Subjects and Methods Thirty nine patients with incompletely treated single HCC (≤ 5 cm) after TACE were treated with RF ablation. All patients were evaluated for complete tumor ablation rate, local recurrence-free rate, overall survival rate, and complications. Local recurrence-free rate and overall survival rate were calculated using the Kaplan-Meier method. The possible prognostic factors of local recurrence-free rate and survival rate were analyzed using Cox proportional-hazards regression model. Results The complete tumor ablation rate was 92.3%. Local recurrence-free rates for 1-, 2-, 3-, and 5-years were 81.7%, 63.1%, 53.6%, and 35.7%, respectively. One-, 2-, 3-, and 5-year overall survival rates were 96.9%, 82.9%, 67.8%, and 48.4%, respectively. Among prognostic factors included in the analysis, only tumor diameter (≤ 2 cm versus > 2 cm) was statistically significant in terms of predicting local recurrence. Complications were observed in two patients, one with liver abscess and the other with portal venous thrombosis. Conclusion Ultrasound-guided RF ablation could be effective and safe in treating incompletely treated HCC after TACE. The diameter of HCC was a significant prognostic factor for local recurrence. PMID:22563280

  15. [Does radiofrequency ablation of the bundle of Kent results in a lower risk of atrial fibrillation?].

    PubMed

    Brembilla-Perrot, B; Beurrier, D; Houriez, P

    2002-02-01

    Radiofrequency ablation of the Bundle of Kent is a common method of treating malignant forms of the Wolff-Parkinson-White syndrome and the paroxysmal junctional tachycardia which may complicate this condition. The aim of this study was to investigate the effects of ablation of a latent or patent Bundle of Kent on the prevention of atrial fibrillation. One hundred and thirty eight patients aged 15 to 81 years of age with one or more patent (Group I) (n = 96) or latent Bundles of Kent (Group II) (n = 42) underwent successful ablation of the Bundle of Kent. Five patients in Group I (5%) and 4 in Group II (9.5%) had spontaneous paroxysmal atrial fibrillation before ablation. During electrophysiological investigation, AF was induced in 7 patients, 2 of whom had spontaneous AF in Group I and 3 in Group II. During follow-up (3 +/- 1 years), 3 patients of Group I went on to develop AF: 2 of them had never had the arrhythmia before: 4 patients of Group II, including 2 with previous AF, went on to develop AF. The risk of spontaneous AF was correlated to older ages. The authors conclude that persistence of the risk of spontaneous AF after ablation of a Bundle of Kent should be investigated especially in patients over 45 years of age.

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

    PubMed

    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.

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

    SciTech Connect

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

    2008-05-15

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

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

    PubMed

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

    2016-04-01

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

  19. [Contrast-enhanced sonography. Therapy control of radiofrequency ablation and transarterial chemoembolization of hepatocellular carcinoma].

    PubMed

    Jung, E M; Uller, W; Stroszczynski, C; Clevert, D-A

    2011-06-01

    Due to the imaging of dynamic perfusion, hepatocellular carcinoma can be detected with a sensitivity of >90% using contrast-enhanced sonography. The characterization of liver tumors with contrast-enhanced sonography is comparable to the diagnostic accuracy of contrast-enhanced computed tomography. The dynamic detection of microvascularization with contrast-enhanced sonography allows the differentiation between vascularized tumors and non-vascularized necrotic lesions before, during and after transarterial chemoembolization or percutaneous radiofrequency ablation. Image fusion with volume navigation can be useful in the followup control.

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

    PubMed

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

    2014-08-01

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

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

    PubMed

    Artner, J; Klessinger, S

    2015-10-01

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

  2. [Successful radiofrequency catheter ablation of the symptomatic ventricular tachycardia in structurally normal heart. Case report].

    PubMed

    Maciag, Aleksander; Sterliński, Maciej; Pytkowski, Mariusz; Jankowska, Agnieszka; Szwed, Hanna

    2003-12-01

    Radiofrequency catheter ablation (RFA) in structurally normal heart ventricular arrhythmias has been found to be promising direction of develop. Authors presented the case of successful RFA of symptomatic ventricular tachycardia originating from right ventricle outflow tract (RVOT). Arrhythmogenic locus was localised basing on ECG pattern, analyze of endocardial potentials and pace mapping method. In two-year follow up she was free of symptoms and ventricular arrhythmia, no medication needed. RFA is an effective and safe therapy in ventricular tachycardia in structurally normal heart.

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

    PubMed Central

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

    2015-01-01

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

  4. Needle track seeding after radiofrequency ablation for hepatocellular carcinoma: prevalence, impact, and management challenge

    PubMed Central

    Francica, Giampiero

    2017-01-01

    Neoplastic seeding may arise after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). A low risk of seeding after RFA (0–1.1%) has been reported, which may rise up to 2.5% if ablation followed diagnostic biopsy. Needle track seeding presents with one or multiple rounded nodules along the needle track located within the peritoneum, along the abdominal muscles, which were penetrated by the needle, pleural surface, or in the subcutaneous and cutaneous tissues. The most widely used method for the assessment of seeding nodules is ultrasound (US), which usually displays hypoechoic nodules with intralesional vascularization. Fine needle aspiration biopsy of the nodule suspicious for malignant implant is mandatory to confirm the diagnosis and plan therapy. Wide surgical excision is the treatment of choice for neoplastic seeding. Thanks to early diagnosis and prompt treatment, development of needle track seeding is not likely to affect the long-term survival of patients. PMID:28176952

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

    PubMed

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

    2016-03-21

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

  6. Laparoscopic Repair of a Diaphragmatic Hernia Associated with Radiofrequency Ablation for Hepatocellular Carcinoma: Lessons from a Case and the Review of the Literature

    PubMed Central

    Nomura, Ryohei; Tokumura, Hiromi; Furihata, Makoto

    2014-01-01

    We describe the case of a patient with a diaphragmatic hernia associated with radiofrequency ablation for hepatocellular carcinoma who was successfully treated by laparoscopic surgery. A 62-year-old man with a long history of hepatitis C-induced liver cirrhosis was admitted to our institution because of recurrent postprandial periumbilical pain. Eight years earlier, he had undergone radiofrequency ablation for hepatocellular carcinoma at hepatic segment VIII. Computed tomography, gastrografin enema examination revealed transverse colon obstruction because of a diaphragmatic hernia. We diagnosed diaphragmatic hernia associated with the prior radiofrequency ablation treatment. The patient underwent laparoscopic repair of the diaphragmatic hernia. Though the patient experienced the recurrence once, relaparoscopic treatment has improved the patient's conditions. Thus, diaphragmatic hernia can develop as a complication of radiofrequency ablation treatment. A laparoscopic approach is safe, feasible, and minimally invasive, even in patients with cirrhosis who develop iatrogenic diaphragmatic hernia as a complication of radiofrequency ablation treatment. PMID:25058770

  7. Laparoscopic repair of a diaphragmatic hernia associated with radiofrequency ablation for hepatocellular carcinoma: lessons from a case and the review of the literature.

    PubMed

    Nomura, Ryohei; Tokumura, Hiromi; Furihata, Makoto

    2014-01-01

    We describe the case of a patient with a diaphragmatic hernia associated with radiofrequency ablation for hepatocellular carcinoma who was successfully treated by laparoscopic surgery. A 62-year-old man with a long history of hepatitis C-induced liver cirrhosis was admitted to our institution because of recurrent postprandial periumbilical pain. Eight years earlier, he had undergone radiofrequency ablation for hepatocellular carcinoma at hepatic segment VIII. Computed tomography, gastrografin enema examination revealed transverse colon obstruction because of a diaphragmatic hernia. We diagnosed diaphragmatic hernia associated with the prior radiofrequency ablation treatment. The patient underwent laparoscopic repair of the diaphragmatic hernia. Though the patient experienced the recurrence once, relaparoscopic treatment has improved the patient's conditions. Thus, diaphragmatic hernia can develop as a complication of radiofrequency ablation treatment. A laparoscopic approach is safe, feasible, and minimally invasive, even in patients with cirrhosis who develop iatrogenic diaphragmatic hernia as a complication of radiofrequency ablation treatment.

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

    PubMed Central

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

    2016-01-01

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

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

    SciTech Connect

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

    2011-02-15

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

  10. Results of a comparative study of low energy direct current with radiofrequency ablation in patients with the Wolff-Parkinson-White syndrome.

    PubMed Central

    Lemery, R; Talajic, M; Roy, D; Lavoie, L; Coutu, B; Hii, J T; Radzik, D; Lavallee, E; Cartier, R

    1993-01-01

    OBJECTIVE--To compare two new power sources for catheter ablation in patients with the Wolff-Parkinson-White syndrome. DESIGN--120 consecutive patients with accessory pathways had catheter ablation. Low energy direct current (DC) was used in the first 60 patients and radio-frequency current in the next 60 patients. SETTING--Electrophysiological laboratory of a large heart institute. PATIENTS--72 men and 48 women (mean (SD) age 35 (14) years (range 9-75)). The accessory pathways were in the left free wall in 73 patients. They were posteroseptal in 35 patients, in the right free wall in five, and anteroseptal in seven. There was no significant difference in the clinical or electrophysiological variables between the two ablation groups. RESULTS--Catheter ablation with low energy direct current was successful in 55/60 patients (92%) and radiofrequency energy was successful in 52/60 patients (87%). Low energy direct current was also successful in four of the eight patients in whom radiofrequency ablation had failed. Radiofrequency ablation was successful in two of the five patients in whom low energy direct current ablation had failed. The mean (SD) procedure and fluoroscopy times for successful ablation were 3.2 (1.5) h and 61 (40) min respectively. These times were similar for both power sources. Accessory pathway conduction recurred in 17 patients (28%) who had low energy direct current and four patients (7%) who received radiofrequency energy (p < 0.004). All patients with recurrence of an accessory pathway had successful re-ablation. CONCLUSIONS--Both new power sources successfully ablated accessory pathways, (overall success rate 94% (113/120 patients)). Radiofrequency ablation, however, did not require general anaesthesia and was associated with a significantly lower rate of recurrence of accessory pathway conduction. Therefore radiofrequency should be used initially for ablation. Low energy direct current may be most useful as a back-up in patients in whom

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

    NASA Astrophysics Data System (ADS)

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

    2010-07-01

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

  12. Intracardiac rhabdomyomas producing symptoms in infancy: the role of radiofrequency catheter ablation

    PubMed Central

    Emmel, M.; Brockmeier, K.; Sreeram, N.

    2006-01-01

    Background Cardiac rhabdomyomas, although benign, may produce symptoms related to arrhythmia or mechanical obstruction. Surgical excision is the therapy of choice for symptomatic rhabdomyomas in infancy. Patients and Methods Two infants with intracardiac rhabdomyomas producing symptoms underwent radiofrequency catheter ablation of the tumour. In patient 1 the diagnosis of multiple rhabdomyomas associated with recurrent supraventricular tachyarrhythmias and foetal hydrops was made in utero. After birth, several antiarrhythmic agents were administered, without successful suppression of the tachyarrhythmia. At seven months of age, the infant had one large residual tumour on the left atrial aspect of the anterior mitral valve leaflet with associated pre-excitation and re-entrant supraventricular tachyarrhythmia suggestive of a left-sided pathway. Catheter ablation of the accessory pathway was performed via a retrograde femoral arterial approach, targeting the earliest site of ventricular activation. Patient 2 presented as a neonate with multiple rhabdomyomas, one of which, measuring 15 mm × 15 mm, was producing severe mitral valve inflow obstruction resulting in symptoms of heart failure due to a large left-to-right shunt at atrial level and persistent pulmonary hypertension. Via the femoral vein, a 5F ablation catheter was advanced across the atrial septum, and the tumour directly ablated. Results Echocardiography performed 24 hours later demonstrated alteration in tumour morphology, with the development of a large central echolucent area, followed by progressive tumour shrinkage in both infants. Patient 1 was discharged at 24 hours, and patient 2 at seven days post-ablation, without symptoms. Follow-up at four weeks confirmed further tumour shrinkage. Conclusion Transcatheter tumour ablation may be beneficial in selected infants and children. ImagesFigure 2AFigure 2BFigure 2CFigure 3AFigure 3BFigure 3C PMID:25696636

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

    PubMed Central

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

    2012-01-01

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

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

    SciTech Connect

    Hong, Cheng William Chow, Lucy; Turkbey, Evrim B.; Lencioni, Riccardo; Libutti, Steven K.; Wood, Bradford J.

    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.

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

    PubMed Central

    2016-01-01

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

  16. [Experience with radiofrequency ablation in the treatment of unresectable pelvic recurrence of rectal cancer].

    PubMed

    Mátrai, Zoltán; Fehér, István; Péley, Gábor; Rényi Vámos, Ferenc; Farkas, Emil; Sulyok, Zoltán; Kovács, Tibor; Köves, István

    2005-02-01

    More than half of colorectal cancers are located in the rectum, and the number of such cancers is increasing. In Hungary colorectal cancers are diagnosed predominantly in advanced stages. In the last five years 736 patients with colorectal cancer were operated on at our Department, with the following stage distribution: Dukes A 10%, BI 10%, B2 31%, C 36% and D 13%. The local recurrence rate is decreasing since the introduction of total mesorectal excision and preoperative radiation. Effective treatment options are however poor for unresectable pelvic recurrences. Chemo- and radiotherapy have severe limitations in this advanced stage cancer. In recent years there are a few publications on the minimal-invasive radiofrequency tumour ablation (RFTA) technique, which is an effective treatment for primary and metastatic liver carcinomas and is a new palliative for the local treatment of pelvic recurrence. The aim of this study was to assess the response to treatment using ultrasound-guided radiofrequency ablation in two patients with unresectable pelvic recurrent rectal cancer.

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

    PubMed Central

    Wong, Joshua; Weyker, Paul D.

    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. PMID:27822391

  18. Radiofrequency Ablation and Excision of Multiple Cutaneous Lesions in Neurofibromatosis Type 1

    PubMed Central

    Kim, Seong-Hun; Lee, Nae-Ho; Yang, Kyung-Moo

    2013-01-01

    Background Von Recklinghausen disease or neurofibromatosis type 1 is an autosomal dominant genetic disorder of chromosome 17q11.2. The most common characteristic findings of NF 1 include multiple and recurrent cutaneous neurofibromas associated with psychosocial distress. Methods Sixteen patients (9 female, 7 male; average age, 31 years; range, 16 to 67 years) with multiple cutaneous neurofibromas between March 2010 and February 2012 were included in the study. All patients were treated with radiosurgical ablation and excision under general anesthesia. Results All 16 patients were satisfied with the results, when questioned directly during the outpatient department follow-up. The only complaint from a few patients was minimal scarring, but acceptable results were obtained in the end. Conclusions The radiofrequency procedure is almost bloodless and quick, creating a smaller necrotizing zone. Therefore, instead of employing the time consuming traditional surgery, such as laser therapy and electrosurgical excision, that produces uncertain results and can affect normal adjacent tissue, treatment of neurofibromas with radiofrequency ablation and excision can be an alternative choice of treatment for patients with a large number of neurofibromas. PMID:23362481

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

    SciTech Connect

    McEachen, James C.; Leng, Shuai; Atwell, Thomas D.; Tollefson, Matthew K.; Friese, Jeremy L.; Wang, Zhen; Murad, M. Hassan; Schmit, Grant D.

    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.

  20. Percutaneous computed tomography-guided radiofrequency thermal ablation of small unresectable lung tumours.

    PubMed

    Rossi, S; Dore, R; Cascina, A; Vespro, V; Garbagnati, F; Rosa, L; Ravetta, V; Azzaretti, A; Di Tolla, P; Orlandoni, G; Pozzi, E

    2006-03-01

    The aim of the current study was to evaluate the safety and the efficacy of radiofrequency thermal ablation (RFTA) for the treatment of nonsmall cell lung cancer (NSCLC) and isolated pulmonary metastases (METs) from colorectal cancer (CRC). A total of 31 patients (15 with NSCLCs and 16 with CRC lung METs), with 36 lung tumour nodules (mean+/-sd diameter: 22+/-8 mm, range: 10-35 mm) underwent computed tomography (CT)-guided RFTA using expandable electrodes. Contrast-enhanced CT was performed before and after (immediately and 30+/-5 days) each RFTA session to assess immediate results and complications and repeated 3 and 6 months post-RFTA, as well as every 6 months thereafter, to evaluate long-term results. Complete radiological necrosis was defined as a nonenhancing area at the tumour site that was equal to or larger than the treated tumour; persistence of enhancement at the tumour site indicated incomplete treatment. Local recurrence was defined as an increase in tumour size and/or enhancing tissue at the tumour site. Complete radiological necrosis of the 36 tumours was achieved with 39 RFTA sessions and 42 electrode insertions. No major complications or deaths were observed. Six patients experienced mild-to-moderate pain during the procedure. There were five cases of pneumothorax, none requiring drainage and four cases of pneumonia, which were successfully treated with antibiotics. After a mean follow-up of 11.4+/-7.7 months (range of 3-36 months), the overall local recurrence rate was 13.9% (20 and 9.5% for NSCLC and CRC-METs patients, respectively). Nineteen of the 31 (61.3%) patients were alive (15 apparently disease free) and 12 (38.7%) had died (three from causes unrelated to their cancer). Radiofrequency thermal ablation seems to be a safe, effective method for producing complete ablation of small nonsmall cell lung cancers and pulmonary colorectal cancer metastases.

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

    SciTech Connect

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

    2005-12-15

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

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

    PubMed Central

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

    2015-01-01

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

  3. Short-Term Results of Laparoscopic Radiofrequency Ablation Using a Multipolar System for Localized Hepatocellular Carcinoma

    PubMed Central

    Morimoto, Naoki; Isoda, Norio; Takaoka, Yoshinari; Hirosawa, Takuya; Watanabe, Shunji; Otake, Toshiya; Murayama, Kozue; Fujieda, Takeshi; Tsukui, Mamiko; Miyata, Natsumi; Ono, Kohei; Yamaguchi, Shota; Yamamoto, Hironori

    2017-01-01

    Background and Aim Multipolar radiofrequency ablation (RFA) is feasible for the treatment of hepatocellular carcinoma (HCC) for which a large ablative area is planned, and it imposes a light physical burden on patients. Multipolar RFA via the percutaneous approach is performed in the majority of cases, but the efficacy of multipolar RFA with a laparoscopic approach has rarely been studied. This study aimed to evaluate the efficacy and safety of multipolar laparoscopic RFA (LRA) for localized HCC over the short term. Methods From January 2014 to January 2016, 77 consecutive patients with 130 HCCs treated by multipolar LRA were assessed. One to three bipolar needle applicators were inserted under laparoscopic ultrasonography guidance, regardless of tumor location. We intended to achieve parallel insertions and no-touch ablation as much as possible. Results The median size of the main tumor was 22 mm (range, 10-42 mm). The median follow-up time was 13.6 months (range, 3.1-24.8 months). In all cases, a sufficient ablative area was obtained as planned, without thermal injury of adjacent organs. During the follow-up period, all patients were alive with no local tumor progression, while intrahepatic recurrence distant from the primary site occurred in 7 patients. The 2-year local tumor progression-free survival rate and overall cancer-free survival rate were 100 and 81.6%, respectively. There were no procedural major complications caused prolonging the hospitalization, and all patients were discharged without subjective symptoms 4-7 days after LRA. Conclusions Multipolar LRA was efficacious in the treatment of localized HCCs by safely achieving a good ablative area. PMID:28275580

  4. Radiofrequency ablation of numerous premature ventricular contractions in a cardiac resynchronisation therapy patient: a long-term follow-up.

    PubMed

    Farkowski, Michał Mirosław; Chwyczko, Tomasz; Sterliński, Maciej; Syska, Paweł; Szwed, Hanna; Pytkowski, Mariusz

    2013-01-01

    We present a case study of a patient with dilated cardiomyopathy and a cardiac resynchronisation therapy (CRT) device who was repeatedly hospitalised due to heart failure (HF) exacerbations. A successful radiofrequency ablation of numerous premature ventricular contractions enabled the proper action of CRT and stabilised the patient's condition in NYHA II without HF subsequent hospitalisations during a 30 month follow-up.

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

    PubMed Central

    Çolak, Abdurrahim; Kaya, Ugur; Ceviz, Munacettin; Becit, Necip; Kocak, Hikmet

    2016-01-01

    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. PMID:27849303

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

    PubMed Central

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

    2009-01-01

    The main limitation of radiofrequency (RF) ablation numerical simulations reported in the literature is their failure to provide statistical results based on the statistical variability of tissue thermal–electrical parameters. This work developed an efficient probabilistic approach to hepatic RF ablation in order to statistically evaluate the effect of four thermal–electrical properties of liver tissue on the uncertainty of the ablation zone dimensions: thermal conductivity, specific heat, blood perfusion and electrical conductivity. A deterministic thermal–electrical finite element model of a monopolar electrode inserted in the liver was coupled with the unscented transform method in order to obtain coagulation zone confidence intervals, probability and cumulative density functions. The coagulation zone volume, diameter and length were 10.96 cm3, 2.17 cm and 4.08 cm, respectively (P < 0.01). Furthermore, a probabilistic sensitivity analysis showed that perfusion and thermal conductivity account for >95% of the variability in coagulation zone volume, diameter and length. PMID:19124948

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

    PubMed

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

    2014-01-01

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

  8. Endoscopic radiofrequency ablation combined with fully covered self-expandable metal stent for inoperable periampullary carcinoma in a liver transplant patient

    PubMed Central

    Tian, Qing; Wang, Guijie; Zhang, Yamin; Jin, Yan; Cui, Zilin; Sun, Xiaoye; Shen, Zhongyang

    2017-01-01

    Abstract Rationale: Postliver transplant periampullary carcinoma is an extremely uncommon disease. Patient concerns: Cutaneous jaundice in a patient who had received a liver transplant 4 years earlier. Diagnosis: Periampullary carcinoma. Interventions: Radiofrequency ablation plus fully covered self-expanding metal stents (FCSEMS). Outcomes: The treatment of malignant neoplasm of the ampulla of Vater is the patient by radiofrequency ablation plus FCSEMS placement was successful. No complications occurred. Lessons: This is the first reported case of a liver transplant patient with inoperable periampullary carcinoma successfully treated by radiofrequency ablation plus FCSEMS placement. Our experience will be useful to other surgeons in managing similar patients in the future. PMID:28151854

  9. Visualization of risk structures for interactive planning of image guided radiofrequency ablation of liver tumors

    NASA Astrophysics Data System (ADS)

    Rieder, Christian; Schwier, Michael; Weihusen, Andreas; Zidowitz, Stephan; Peitgen, Heinz-Otto

    2009-02-01

    Image guided radiofrequency ablation (RFA) is becoming a standard procedure as a minimally invasive method for tumor treatment in the clinical routine. The visualization of pathological tissue and potential risk structures like vessels or important organs gives essential support in image guided pre-interventional RFA planning. In this work our aim is to present novel visualization techniques for interactive RFA planning to support the physician with spatial information of pathological structures as well as the finding of trajectories without harming vitally important tissue. Furthermore, we illustrate three-dimensional applicator models of different manufactures combined with corresponding ablation areas in homogenous tissue, as specified by the manufacturers, to enhance the estimated amount of cell destruction caused by ablation. The visualization techniques are embedded in a workflow oriented application, designed for the use in the clinical routine. To allow a high-quality volume rendering we integrated a visualization method using the fuzzy c-means algorithm. This method automatically defines a transfer function for volume visualization of vessels without the need of a segmentation mask. However, insufficient visualization results of the displayed vessels caused by low data quality can be improved using local vessel segmentation in the vicinity of the lesion. We also provide an interactive segmentation technique of liver tumors for the volumetric measurement and for the visualization of pathological tissue combined with anatomical structures. In order to support coagulation estimation with respect to the heat-sink effect of the cooling blood flow which decreases thermal ablation, a numerical simulation of the heat distribution is provided.

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

    NASA Astrophysics Data System (ADS)

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

    2010-02-01

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

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

    SciTech Connect

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

    2005-06-15

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

  12. Radiofrequency ablation therapy combined with cementoplasty for painful bone metastases: initial experience.

    PubMed

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

    2005-01-01

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

  13. Efficacy and safety of intraoperative radiofrequency ablation in management of hepatocellular carcinoma.

    PubMed

    Rizk, Hesham; Magdy, Mohamed; Reda, Mahmoud; Alaa, Taha; El-Shafie, M Mohamed; Ghanem, Mahmoud; Saed, Tarek

    2008-12-01

    The present study is a prospective one involving 15 consecutive patients with hepatocellular carcinoma (HCC) from January 2003 to December 2005. Clinical and laboratory examinations, abdominal ultrasonography & spiral CT scanning were performed. All patients were subjected to intraoperative radiofrequency ablation of HCC after confirmation by core biopsy. Enhanced dynamic CT was done at 1 month postoperative and every 3 months during follow-up period. Males were 12 with age of 41-69 year (53.2 +/- 7.4). Underlying cirrhosis due to viral hepatitis was in all, and HCV was the most common (75%), and patients (85%) werecategorized in Child B classification. Serum alpha feto protein was above 400 ng/ml in 60%. 12 patients had unifocal HCC (nodules mean diameter of less than 3 cm in 6, 3 to 5 cm in 4, and more than 5 cm in 2), and 3 patients had multifocal HCC (nodules mean number of less than 3 cm in 2 and 3 to 5 cm in 1). The mean number of RF application session to achieve complete necrosis in patients with were 1.52 (unifocal) & 2.49 (multifocal HCC). The mean hospital stay was 14.9 days, with neither mortality nor major complications, but Minor complications in 30%. After one month, complete ablation of HCC nodules was achieved in 10 patients with reduction of alpha fetoprotein in 11 patients. 2/5 with partial ablation were multifocal nodules. Total mortality during follow-up in late post-operative period (1 year) was 6 out of 15 patients. 5 of them are the patients with partial ablation. 3 patients out of 9 patients developed evidence of local recurrence detected by enhanced dynamic CT & raising of serum alpha fetoprotein.

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

    PubMed

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

    2014-06-01

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

  15. Combined hepatectomy and radiofrequency ablation for multifocal hepatocellular carcinoma: a case report

    PubMed Central

    Cipolla, Calogero; Soresi, Maurizio; Re, Giuseppe Lo; Latteri, Federica; Lombardo, Giuseppina; Bova, Valentina; Latteri, Mario Adelfio

    2009-01-01

    Introduction At the present time, the best possible choice for the local management of a multifocal hepatocellular carcinoma (HCC) developing on liver cirrhosis is multimodal treatment of the disease. Combined approach based on simultaneous radiofrequency ablation (RFA) together with limited surgical resection represents a valid choice of treatment. Case presentation A 75-year-old white female patient affected of HCV-associated cirrhosis in Child-Pugh’s functional class A5, developed a bifocal HCC. The patient had undergone a limited surgical resection together with simultaneous RFA, without intraoperative and postoperative surgical complications. At 36 months after surgery, still shows no sign of disease relapse. Conclusion This strategy directed at the management of multifocal HCC, may prove more useful for the reduction of surgical risk and post-operative progression of the liver cirrhosis than large-scale hepatectomy, since it presents no peri-operative mortality and a complication rate of less than 10%. PMID:19830036

  16. Rectouterine fistula after laparoscopic ultrasound-guided radiofrequency ablation of a uterine fibroid

    PubMed Central

    Jeong, Hyo Joo; Kwon, Byung-Su; Choi, Young Joon

    2014-01-01

    In the conservative management of uterine fibroids is radiofrequency ablation (RFA) considered to be one of the safe, effective and minimal invasive approaches in selected women who desire to retain their uterus. Few studies were conducted on its adverse outcomes and most of the reported complications were minor events such as pain, discharge, adhesion which didn't require any intervention. However, although safe and effective, the RFA of a uterine myoma can be the cause for severe complications such as penetration and burn injuries of pelvic organs. In general, a rectouterine fistula is one of the rarest complications but can lead to serious adverse outcomes. Herein, to our knowledge, we report the first case involving a rectouterine fistula after laparoscopic ultrasound-guided RFA of a uterine myoma with pelvic endometriosis. In addition, we provide a brief review of the relevant literature. PMID:25469349

  17. Rectouterine fistula after laparoscopic ultrasound-guided radiofrequency ablation of a uterine fibroid.

    PubMed

    Jeong, Hyo Joo; Kwon, Byung-Su; Choi, Young Joon; Huh, Chu Yeop

    2014-11-01

    In the conservative management of uterine fibroids is radiofrequency ablation (RFA) considered to be one of the safe, effective and minimal invasive approaches in selected women who desire to retain their uterus. Few studies were conducted on its adverse outcomes and most of the reported complications were minor events such as pain, discharge, adhesion which didn't require any intervention. However, although safe and effective, the RFA of a uterine myoma can be the cause for severe complications such as penetration and burn injuries of pelvic organs. In general, a rectouterine fistula is one of the rarest complications but can lead to serious adverse outcomes. Herein, to our knowledge, we report the first case involving a rectouterine fistula after laparoscopic ultrasound-guided RFA of a uterine myoma with pelvic endometriosis. In addition, we provide a brief review of the relevant literature.

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

    NASA Astrophysics Data System (ADS)

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

    2011-11-01

    We simulate the thermal and electrical processes, involved in the radio-frequency ablation procedure. In this study, we take into account the observed fact, that the electrical conductivity of the hepatic tissue varies during the procedure. With the increase of the tissue temperature to a certain level, a sudden drop of the electrical conductivity is observed. This variation was neglected in some previous studies. The mathematical model consists of two parts—electrical and thermal. The energy from the applied AC voltage is determined first, by solving the Laplace equation to find the potential distribution. After that, the electric field intensity and the current density are directly calculated. Finally, the heat transfer equation is solved to determine the temperature distribution. Heat loss due to blood perfusion is also accounted for. The simulations were performed on the IBM Blue Gene/P massively parallel computer.

  19. Inappropriate Sinus Tachycardia Diagnosed and Treated as Depression Successfully Treated by Radiofrequency Catheter Ablation.

    PubMed

    Masumoto, Akihiro; Takemoto, Masao; Mito, Takahiro; Tanaka, Atsushi; Kawano, Yuki; Kumeda, Hiroshi; Kang, Honsa; Matsuo, Atsutoshi; Hida, Satoru; Okazaki, Teiji; Tayama, Kei-Ichiro; Yoshitake, Kiyonobu; Kosuga, Kenichi

    2017-01-01

    We experienced a man in his 20s with inappropriate sinus tachycardia (IST) initially diagnosed and treated as depression who was steadily treated with radiofrequency catheter ablation (RFCA) using an EnSite™ system. The patient has remained well without any symptoms or medications, including antidepressants, for two years since the RFCA. To avoid missing IST and treating it as an emotional problem and/or mental illness such as depression, physicians - including cardiologists - should be aware of these conditions when examining patients with multiple and incapacitating complaints including palpitations and general fatigue and/or tachycardia, especially characterized by an elevated resting heart rate or a disproportionate increase in the heart rate with minimal exertion.

  20. Latent Mahaim fiber as a cause of antidromic reciprocating tachycardia: recognition and successful radiofrequency ablation.

    PubMed

    Davidson, Neil C; Morton, Joseph B; Sanders, Prashanthan; Kalman, Jonathan

    2002-01-01

    The term "Mahaim fiber" usually is applied to an atriofascicular fiber that inserts distally into the right bundle branch and forms the anterograde limb of a reciprocating tachycardia. One of the features that has been used to describe the physiology of Mahaim fibers is the presence of anterograde preexcitation. We describe two patients who had a clinical tachycardia consistent with a "Mahaim tachycardia" in whom there was no evidence or minimal evidence of anterograde preexcitation during sinus rhythm or atrial pacing. In both patients, the tachycardia was rendered noninducible by radiofrequency ablation at the site of Mahaim potentials at the tricuspid annulus, and a long-term cure was achieved. This is the first description of a "latent Mahaim fiber" that does not cause preexcitation but which can support antidromic reciprocating tachycardia.

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

    PubMed Central

    Chen, Luming; Sun, Jihong; Yang, Xiaoming

    2015-01-01

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

  2. When to Perform Surgical Resection or Radiofrequency Ablation for Early Hepatocellular Carcinoma?

    PubMed Central

    Liu, Po-Hong; Hsu, Chia-Yang; Lee, Yun-Hsuan; Hsia, Cheng-Yuan; Huang, Yi-Hsiang; Su, Chien-Wei; Chiou, Yi-You; Lin, Han-Chieh; Huo, Teh-Ia

    2015-01-01

    Abstract Radiofrequency ablation (RFA) is indicated for early-stage hepatocellular carcinoma (HCC), but the comparative efficacy between RFA and surgical resection (SR) is inconclusive. We aim to develop a prognostic nomogram for predicting recurrence-free survival (RFS) after RFA. We also evaluate the possibility of using nomogram in improving treatment algorithm. We retrospectively enrolled 836 patients with Barcelona Clínic Liver Cancer very-early/early-stage HCC receiving SR or RFA. A visually-orientated nomogram was constructed with Cox proportional hazards model, and number and size of tumor, platelet count, albumin level, and model for end-stage liver disease score were included. The concordance index of the nomogram was 0.69. Radiofrequency ablation patients were stratified into low and high-risk groups by the median of nomogram scores. The RFS and overall survival (OS) of 2 risk groups were compared with SR patients with propensity score matching analysis. SR provided better RFS and OS compared with high-risk (nomogram score ≥9.8) RFA patients in the propensity model. The 5-year RFS rates were 36% versus 11%, whereas the 5-year OS rates were 74% versus 60% for SR and high-risk RFA groups, respectively (both P < 0.05). However, SR was associated with better RFS (5-year RFS rates 41% vs 29%), but similar OS (5-year OS rates 80% vs 81%), compared with low-risk (nomogram score <9.8) RFA patients in the propensity model (P < 0.05 and P > 0.05, respectively). In conclusion, this user-friendly nomogram offers individualized recurrence risk estimation and stratification for early HCC patients receiving curative RFA. The nomogram can be integrated into current treatment algorithm. SR should be considered the first-line treatment for high-risk patients to achieve better long-term survival. PMID:26512576

  3. Comparison of 1470 nm Laser and Radial 2ring Fiber with 980 nm Laser and Bare-Tip Fiber in Endovenous Laser Ablation of Saphenous Varicose Veins: A Multicenter, Prospective, Randomized, Non-Blind Study

    PubMed Central

    Ogawa, Tomohiro; Sugawara, Hiromitsu; Shokoku, Shintaro; Sato, Shoji

    2015-01-01

    Objective: The aim of this study is to compare the clinical efficacy and safety of two laser wavelengths and fiber types in endovenous laser ablation (EVLA) of saphenous varicose veins of the lower limb. Design: Multi-center prospective randomized non-blind clinical trial. Patients and Methods: From January 2007 to December 2011, 113 patients (113 limbs) with primary varicose veins were randomized into two groups. They were treated with radial 2ring fiber and 1470 nm laser in Group I (57 limbs) and bare-tip fiber and 980 nm laser in Group E (56 limbs) in order to ablate the saphenous vein. Vein occlusion rates at 12 weeks and pain in treated region were recorded as primary endpoint. Visual analogue scale (VAS) for assessment of pain, rates of bruising, complications and equipment failure were recorded as secondary endpoint of safety. Results: Occlusion rates at 12 weeks were 100% in both groups. Rates of pain (0% vs. 25.0%) and bruising (7.0% vs. 57.1%) were significantly lower in Group I (p <0.0001). VAS of pain was significantly lower on postoperative day 1, day 5 and 2nd week in Group I. Conclusion: Treatment of saphenous varicose veins by EVLA using a 1470 nm laser and a radial 2ring fiber resulted in comparable occlusion rates at 12 weeks and less postoperative pain and bruising than EVLA with a 980 nm laser and a bare-tip fiber. (This article is a translation of Jpn J Vasc Surg 2014; 23: 964–971.) PMID:26730252

  4. 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

    PubMed Central

    Wang, Xin; Hu, Yanan; Ren, Mudan; Lu, Xinlan; Lu, Guifang

    2016-01-01

    Objective To compare the efficacy and safety of combined radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) with RFA alone for hepatocellular carcinomas (HCC). Materials and Methods 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. Results 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). Conclusion 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. PMID:26798221

  5. 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

    SciTech Connect

    Hyun, Dongho; Cho, Sung Ki 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

    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.

  6. 27.12 MHz Radiofrequency Ablation for Benign Cutaneous Lesions

    PubMed Central

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

    2016-01-01

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

  7. Radiofrequency ablation of benign thyroid nodules: safety and imaging follow-up in 236 patients.

    PubMed

    Jeong, Woo Kyoung; Baek, Jung Hwan; Rhim, Hyunchul; Kim, Yoon Suk; Kwak, Min Sook; Jeong, Hyun Jo; Lee, Ducky

    2008-06-01

    This study evaluated the safety and volume reduction of ultrasonography (US)-guided radiofrequency ablation (RFA) for benign thyroid nodules, and the factors affecting the results obtained. A total of 302 benign thyroid nodules in 236 euthyroid patients underwent RFA between June 2002 and January 2005. RFA was carried out using an internally cooled electrode under local anesthesia. The volume-reduction ratio (VRR) was assessed by US and safety was determined by observing the complications during the follow-up period (1-41 months). The correlation between the VRR and several factors (patient age, volume and composition of the index nodule) was evaluated. The volume of index nodules was 0.11-95.61 ml (mean, 6.13 +/- 9.59 ml). After ablation, the volume of index nodules decreased to 0.00-26.07 ml (mean, 1.12 +/- 2.92 ml) and the VRR was 12.52-100% (mean, 84.11 +/- 14.93%) at the last follow-up. A VRR greater than 50% was observed in 91.06% of nodules, and 27.81% of index nodules disappeared. The complications encountered were pain, hematoma and transient voice changes. In conclusion, RFA is a safe modality effective at reducing volume in benign thyroid nodules.

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

    PubMed

    Jin, Chao; He, Zhizhu; Liu, Jing

    2014-02-01

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

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

    NASA Astrophysics Data System (ADS)

    Daniels, Matthew J.; Varghese, Tomy

    2010-08-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-10-01

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

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

    SciTech Connect

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

    2013-10-15

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

  14. Ablation of large HCCs using a new saline-enhanced expandable radiofrequency device☆

    PubMed Central

    Tarantino, L.; Sordelli, I.; Nocera, V.; Piscopo, A.; Ripa, C.; Parmeggiani, D.; Sperlongano, P.

    2009-01-01

    Purpose Evaluation of a new device designed to achieve large volumes of necrosis in hepatocellular carcinoma (HCC) nodules by application of radiofrequency ablation (RFA). Materials and Methods 29 consecutive patients with 31 HCC nodules ≥3 cm in diameter (range 3–7.5 cm; mean diameter 5.5 cm) underwent ultrasound (US) guided percutaneous RFA using an expandable electrode with 7 active arrays and saline injection designed to create tissue ablation in areas of up to 7 cm (Starburst XLi-enhanced RFA device). Treatment was performed in general anesthesia (6 patients) or deep sedation (23 patients). Treatment efficacy was assessed by three-phase contrast-enhanced computed tomography (CT) and bimonthly US follow-up. Results One to three electrode insertions (mean number 1.6) were performed in each patient. CT showed complete necrosis in 23/31 HCC nodules (74%) in 22 patients. Follow-up of these 22 patients ranged from 2 to 15 months (mean time 8.3 months). In 6/22 patients (28%) intrahepatic recurrence occurred within 5–10 months (mean time 8.3 months). Major complications were post-ablation syndrome in 7/29 (24%), peritoneal effusion in 4/29 (14%), pleural effusion in 2/29 (7%) and transient obstructive jaundice in 1/29 (3.4%) patients. One patient died 6 months after treatment because of tumor progression. Conclusions In the treatment of large HCC nodules, Starburst XLi-enhanced is an effective and safe device. PMID:23396886

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

    SciTech Connect

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

    2013-06-15

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

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

    SciTech Connect

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

    2013-06-15

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

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

    PubMed Central

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

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

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

    SciTech Connect

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

    2011-06-15

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

  20. Percutaneous thrombin injection treatment of a gluteal pseudoaneurysm following radiofrequency ablation of a hip osteoid osteoma in a 6-year-old boy.

    PubMed

    Kumar, Abhishek; Ramchand, Tekchand; Contractor, Sohail

    2014-12-01

    Osteoid osteomas are benign bone lesions that present with bone pain in children and young adults. Over the last 2 decades, radiofrequency ablation has become the mainstay of treatment and is now preferred over surgical resection. Major complications of the procedure are very rare, consisting mostly of local skin burns. We present a case of a child presenting with a gluteal pseudoaneursym following CT-guided radiofrequency ablation of an acetabular osteoid osteoma, which was then treated successfully with percutaneous thrombin injection.

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2014-06-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    SciTech Connect

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

    2010-02-15

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

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

    SciTech Connect

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

    2010-06-15

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

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

    Cancer.gov

    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. |

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2013-01-01

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

  10. Treatment of uterine myomas by radiofrequency thermal ablation: a 10-year retrospective cohort study.

    PubMed

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

    2015-05-01

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

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

    SciTech Connect

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

    2006-12-15

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

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

    PubMed Central

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

    2015-01-01

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

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

    SciTech Connect

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

    2007-11-15

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

  14. Clinical Assessment of Percutaneous Radiofrequency Ablation for Painful Metastatic Bone Tumors

    SciTech Connect

    Kojima, Hiroyuki Tanigawa, Noboru; Kariya, Shuji; Komemushi, Atsushi; Shomura, Yuzo; Sawada, Satoshi

    2006-12-15

    Purpose. To investigate the pain-alleviating effects of radiofrequency ablation (RFA) on metastatic bone tumors in relation to tumor size, combined therapy, and percent tumor necrosis rate following RFA. Methods. Subjects comprised 24 patients with 28 painful metastatic bone tumors. A 17G internally cooled electrode was inserted into the tumor for CT guidance and ablation was performed. Bone cement was injected following RFA for 4 tumors involving a weight-bearing bone, while 5 tumors were treated using combined RFA and external irradiation. Percent necrosis rate of the tumor was measured using contrast-enhanced computed tomography 1 week after RFA. Results. Improvement in the visual analog scale (VAS) score was 4.6 {+-} 2.2 for large tumors (>5 cm, n = 12), 3.7 {+-} 1.8 for medium-sized tumors (3.1-5.0 cm, n = 11), and 3.5 {+-} 1.7 for small tumors ({<=}3 cm, n = 4), with no significant differences noted among tumor sizes. Improvement in the VAS score was 3.5 {+-} 1.3 for the 4 tumors in the RFA + bone cement group, 3.2 {+-} 1.9 for the 5 tumors in the RFA + radiation therapy group, and 4.8 {+-} 2.2 for the 18 tumors in the RFA group. No significant differences were identified between groups. The improvement in the VAS score was 3.8 {+-} 2.3, 4.0 {+-} 1.9, and 4.7 {+-} 2.6 in patients with tumor necrosis rates of 0-49%, 50-74%, and 75-100%, respectively. No significant association was observed among these three groups. Conclusion. Percutaneous RFA therapy was effective in relieving pain due to metastatic bone tumors. No relationships appear to exist between initial response and tumor size, combined therapy, and percent tumor necrosis.

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

    SciTech Connect

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

    2011-10-15

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

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

    PubMed Central

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

    2015-01-01

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

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

    SciTech Connect

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

    2012-06-15

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

  18. CT-guided versus laparoscopic radiofrequency ablation in recurrent small hepatocellular carcinoma against the diaphragmatic dome

    PubMed Central

    Ding, Huaiyin; Su, Mu; Zhu, Chuandong; Wang, Lixue; Zheng, Qin; Wan, Yuan

    2017-01-01

    Computed tomography-guided radiofrequency ablation (CT-RFA) and laparoscopic RFA (L-RFA) have been used to treat intrahepatic recurrent small hepatocellular carcinoma (HCC) against the diaphragmatic dome. However, the therapeutic safety, efficacy, and hospital fee have never been compared between the two techniques due to scarcity of cases. In this retrospective study, 116 patients were divided into two groups with a total of 151 local recurrent HCC lesions abutting the diaphragm. We compared overall survival (OS), local tumor progression (LTP), postoperative complications, and hospital stay and fee between the two groups. Our findings revealed no significant differences in 5-year OS (36.7% vs. 44.6%, p = 0.4289) or 5-year LTP (73.3% vs. 67.9%, p = 0.8897) between CT-RFA and L-RFA. The overall hospital stay (2.8 days vs. 4.1 days, p < 0.0001) and cost (¥ 19217.6 vs. ¥ 25553.6, p < 0.0001) were significantly lower in the CT-RFA in comparison to that of L-RFA. In addition, we elaborated on the choice of percutaneous puncture paths depending on the locations of the HCC nodules and 11-year experience with CT-RFA. In conclusion, CT-RFA is a relatively easy and economic technique for recurrent small HCC abutting the diaphragm, and both CT-RFA and L-RFA are effective techniques. PMID:28291254

  19. Changes in emotional state of snoring and obstructive sleep apnea patients following radiofrequency tissue ablation.

    PubMed

    Uloza, Virgilijus; Balsevicius, Tomas; Sakalauskas, Raimundas; Miliauskas, Skaidrius; Zemaitiene, Nida

    2009-09-01

    A total of 37 primary snoring and obstructive sleep apnea hypopnea syndrome (OSAHS) patients were treated with two sessions of radiofrequency tissue ablation (RFTA) to assess the relationship among RFTA and sleepiness, anxiety and depression in patients with OSAHS. Patients' sleepiness was rated according to the Epworth sleepiness scale (ESS), anxiety--on Spielberg's trait-state anxiety inventory scale and depression degree--with Beck depression inventory-second edition scale and the patients' major complaints were evaluated using visual analog scales before and after the treatment. A remarkable decrease in patients' complaints, sleepiness and depression after RFTA was observed. The ESS mean score decreased from 9.3 +/- 3.4 to 7.14 +/- 3.2 points (P < 0.05) and Beck depression index mean value decreased from 14.2 +/- 10.8 to 8.7 +/- 7.6 points (P < 0.05), respectively. RFTA is a treatment of choice for snoring and mild to moderate OSAHS. Reduction of sleepiness and depression was statistically significant after RFTA.

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

    PubMed

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

    2014-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-01-01

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

  3. Radiofrequency ablation compared to surgery for the treatment of benign thyroid nodules.

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

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

    PubMed Central

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  8. Long-term risk of fatal malignancy following pediatric radiofrequency ablation.

    PubMed

    Clay, Mark A; Campbell, Robert M; Strieper, Margaret; Frias, Patricio A; Stevens, Mary; Mahle, William T

    2008-10-01

    Children undergoing radiofrequency ablation (RFA) are believed to be at increased risk of developing malignancy caused by radiation, although the magnitude of this risk is incompletely understood. We previously reported a strategy to reduce radiation exposure during pediatric RFA. In a cohort of 15 subjects (median age 12 years, range 9 to 17), radiation was measured using dosimeters at 5 sites. The risk of malignancy using measured radiation absorbed dose was calculated. International Council for Radiation Protection 60 risk estimates were applied to calculate absorbed organ doses. Median duration of combined biplane fluoroscopy was 14.4 minutes. Of the 5 dosimeter locations, the right scapular location had the highest median radiation exposure (43 mGy). Incorporating data from the 5 dosimeters, the risk model calculated that the organ with the greatest absorbed dose and at greatest risk of malignancy was the lung, followed by bone marrow, then breast. Thyroid and ovary exposures were negligible. The increased lifetime risk of fatal malignancy was 0.02% per single RFA procedure. In conclusion, with appropriate measures to reduce radiation exposure, the increased risk of malignancy after a single RFA procedure in children is low. These data should be of help counseling families and will contribute to analysis of the relative risk reduction benefits of such novel imaging approaches as a magnetic resonance imaging-based catheterization laboratory.

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

    PubMed Central

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

    2016-01-01

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

  10. CT-guided versus laparoscopic radiofrequency ablation in recurrent small hepatocellular carcinoma against the diaphragmatic dome.

    PubMed

    Ding, Huaiyin; Su, Mu; Zhu, Chuandong; Wang, Lixue; Zheng, Qin; Wan, Yuan

    2017-03-14

    Computed tomography-guided radiofrequency ablation (CT-RFA) and laparoscopic RFA (L-RFA) have been used to treat intrahepatic recurrent small hepatocellular carcinoma (HCC) against the diaphragmatic dome. However, the therapeutic safety, efficacy, and hospital fee have never been compared between the two techniques due to scarcity of cases. In this retrospective study, 116 patients were divided into two groups with a total of 151 local recurrent HCC lesions abutting the diaphragm. We compared overall survival (OS), local tumor progression (LTP), postoperative complications, and hospital stay and fee between the two groups. Our findings revealed no significant differences in 5-year OS (36.7% vs. 44.6%, p = 0.4289) or 5-year LTP (73.3% vs. 67.9%, p = 0.8897) between CT-RFA and L-RFA. The overall hospital stay (2.8 days vs. 4.1 days, p < 0.0001) and cost (¥ 19217.6 vs. ¥ 25553.6, p < 0.0001) were significantly lower in the CT-RFA in comparison to that of L-RFA. In addition, we elaborated on the choice of percutaneous puncture paths depending on the locations of the HCC nodules and 11-year experience with CT-RFA. In conclusion, CT-RFA is a relatively easy and economic technique for recurrent small HCC abutting the diaphragm, and both CT-RFA and L-RFA are effective techniques.

  11. Cost-Effectiveness of Radiofrequency Ablation for Supraventricular Tachycardia in Guatemala

    PubMed Central

    Rodriguez, Benjamin Cruz; Leal, Sergio; Calvimontes, Gonzalo; Hutton, David

    2015-01-01

    Background Radiofrequency ablation (RFA) is an established but expensive treatment alternative for many forms supraventricular tachycardia (SVT). Currently no studies exist on the cost-effectiveness of RFA compared to medical treatment (MT) in adult Latin American population. Methods Between 2007 and 2012, we identified 103 adults who underwent RFA for SVT in the National Unit of Cardiovascular Surgery (UNICAR) in Guatemala. A decision tree was developed with all clinical outcome parameter estimates obtained from the Adult Electrophysiology Clinic. Costs were obtained from UNICAR's administration. A cost-effectiveness analysis was conducted which evaluated costs and quality adjusted life years (QALYs) to compare interventions in terms of their incremental cost-effectiveness ratios (ICERs). Results The first RFA had 83% success and cumulative 94% success was achieved with a second one. The cost of the RFA procedure itself was $5,411. RFA gains 1.46 QALYs and saves $ 7,993 compared to of MT for patients with SVT. This demonstrates that in Guatemala, RFA dominates MT in the management of SVT. Using assumptions based largely on the outcomes in UNICAR, we found that the RFA is highly cost-effective. This is a consistent finding, even after varying assumptions about efficacy, complication rates and quality of life. Conclusions RFA dominates MT by improving quality of life and reducing expenditures when used to treat severely symptomatic patients with SVT in Guatemala. The robustness of these finding to variations in parameter assumptions, suggests these findings may hold in other similar settings. PMID:26543802

  12. Tachycardiomyopathy Induced by Ventricular Premature Complexes: Complete Recovery after Radiofrequency Catheter Ablation

    PubMed Central

    Rhee, Kyoung-Hoon; Jung, Ju-Young; Kim, Hyun-Sook; Chae, Jei-Keon; Kim, Won-Ho; Ko, Jae-Ki

    2006-01-01

    Ventricular premature complexes (VPCs) are known to be one of the most benign cardiac arrhythmias when they occur in structurally normal hearts. We experienced a 32-year old man who presented with dyspnea, palpitations and very frequent VPCs (31% of the total heart beats). Echocardiography revealed a dilated left ventricle (LV 66 mm at end-diastole and 57 mm at end-systole) and a decreased ejection fraction (34%). Very frequent VPCs had been detected 10 years previously and he underwent a failed radiofrequency catheter ablation (RFCA) procedure at that time. The patient had been treated with heart failure medications including betablockers, ACE inhibitors and spironolactone for the two most recent years. Six months after we eliminated these VPCs with a second RFCA procedure, the heart returned to normal function and size. Long standing and very frequent VPCs could be the cause of left ventricular dysfunction in a subset of patients who suffer with dilated cardiomyopathy, and RFCA should be the choice of therapy for these patients. PMID:17017676

  13. Comparable Outcomes of Ultrasound versus Computed Tomography in the Guidance of Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Lee, Lu-Hung; Hwang, Jen-I; Cheng, Yu-Chi; Wu, Chun-Ying; Lee, Shou-Wu; Yang, Sheng-Shun; Yeh, Hong-Zen; Chang, Chi-Sen; Lee, Teng-Yu

    2017-01-01

    Objectives To compare the efficacy and safety of ultrasound (US) and computed tomography (CT) in the guidance of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Materials and Methods We retrospectively analyzed consecutive treatment-naïve patients who received curative RFA for HCC from January 2008 to July 2013. Patients were divided into the US group or the CT group according to their RFA guidance instruments. Patients who were only suitable for US- or CT-guided RFA were excluded. Cumulative incidences of and hazard ratios for HCC recurrence were analyzed after adjusting for competing mortality risk. Results We recruited a total of 101 patients in the US group and 51 patients in the CT group. The baseline demographic characteristics were not significantly different in both groups. Initial response rates were similar between the two groups (US vs. CT: 89.1% vs. 92.2%, p = 0.54), and complete tumor ablation was finally achieved for all patients. However, more ablations per session were performed in US group (median 2.0 [1.0–3.0] vs. 1.0 [1.0–2.0]; p<0.01). The 1-, 2- and 3-year local tumor recurrence rates (US vs. CT: 13.0%, 20.9%, and 29.2% vs. 11.2%, 29.8% and 29.8%, respectively) and overall mortality rates (US vs. CT: 5.2%, 9.6% and 16.5% vs. 0%, 3.1% and 23.8%, respectively) were not significantly different. In multivariate analysis, tumor characteristics and underlying liver function, but not US or CT guidance, were independent prognostic factors. The complication rates were similar between the two groups (US vs. CT: 10.9% vs. 9.8%; p = 0.71), and there was no procedure-related mortality. Conclusions With comparable major outcomes, either US or CT can be used in the guidance of RFA in experience hands. PMID:28068369

  14. Radiofrequency Ablation of the Main Lesion of Hepatocellular Carcinoma and Bile Duct Tumor Thrombus as a Radical Therapeutic Alternative

    PubMed Central

    Gao, Jun; Zhang, Qingshuai; Zhang, Jun; Kong, Jian; Wang, Shaohong; Ding, Xuemei; Ke, Shan; Sun, Wenbing

    2015-01-01

    Abstract Hepatocellular carcinoma (HCC) with bile duct tumor thrombus (BDTT) formation is a rare entity found microscopically in 1% to 9.2% of resected specimens. The ideal treatment for HCC is surgical resection. However, because of poor hepatic functional reserve in patients with HCC, most tumors are unresectable. Here, we report 2 cases of HCC with BDTT type III accompanied by hepatic dysfunction that were successfully treated with radiofrequency (RF) ablation. We used RF ablation as both a radical therapeutic method and an efficient way to control bleeding from the origin of BDTT after BDTT removal. At the time of writing, the 2 patients have been disease-free for 16 and 12 months, respectively. Our results show that RF ablation may be used as a radical therapeutic alternative for HCC with BDTT in patients with liver cirrhosis and obstructive jaundice. PMID:26166111

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

    SciTech Connect

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

    2009-03-15

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

  16. Dual-energy CT after radiofrequency ablation of liver, kidney, and lung lesions: a review of features.

    PubMed

    Vandenbroucke, Frederik; Van Hedent, Steven; Van Gompel, Gert; Buls, Nico; Craggs, Gordon; Vandemeulebroucke, Jef; Ros, Pablo R; de Mey, Johan

    2015-06-01

    Early detection of residual tumour and local tumour progression (LTP) after radiofrequency (RF) ablation is crucial in the decision whether or not to re-ablate. In general, standard contrast-enhanced computed tomography (CT) is used to evaluate the technique effectiveness; however, it is difficult to differentiate post-treatment changes from residual tumour. Dual-energy CT (DECT) is a relatively new technique that enables more specific tissue characterisation of iodine-enhanced structures because of the isolation of iodine in the imaging data. Necrotic post-ablation zones can be depicted as avascular regions by DECT on greyscale- and colour-coded iodine images. Synthesised monochromatic images from dual-energy CT with spectral analysis can be used to select the optimal keV to achieve the highest contrast-to-noise ratio between tissues. This facilitates outlining the interface between the ablation zone and surrounding tissue. Post-processing of DECT data can lead to an improved characterisation and delineation of benign post-ablation changes from LTP. Radiologists need to be familiar with typical post-ablation image interpretations when using DECT techniques. Here, we review the spectrum of changes after RF ablation of liver, kidney, and lung lesions using single-source DECT imaging, with the emphasis on the additional information obtained and pitfalls encountered with this relatively new technique. Teaching Points •Technical success of RF ablation means complete destruction of the tumour. •Assessment of residual tumour on contrast-enhanced CT is hindered by post-ablative changes. •DECT improves material differentiation and may improve focal lesion characterisation. •Iodine maps delineate the treated area from the surrounding parenchyma well.

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

    PubMed Central

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

    2016-01-01

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

  18. Efficient loading of dendritic cells following cryo and radiofrequency ablation in combination with immune modulation induces anti-tumour immunity

    PubMed Central

    den Brok, M H M G M; Sutmuller, R P M; Nierkens, S; Bennink, E J; Frielink, C; Toonen, L W J; Boerman, O C; Figdor, C G; Ruers, T J M; Adema, G J

    2006-01-01

    Dendritic cells (DC) are professional antigen-presenting cells that play a pivotal role in the induction of immunity. Ex vivo-generated, tumour antigen-loaded mature DC are currently exploited as cancer vaccines in clinical studies. However, antigen loading and maturation of DC directly in vivo would greatly facilitate the application of DC-based vaccines. We formerly showed in murine models that radiofrequency-mediated tumour destruction can provide an antigen source for the in vivo induction of anti-tumour immunity, and we explored the role of DC herein. In this paper we evaluate radiofrequency and cryo ablation for their ability to provide an antigen source for DC and compare this with an ex vivo-loaded DC vaccine. The data obtained with model antigens demonstrate that upon tumour destruction by radiofrequency ablation, up to 7% of the total draining lymph node (LN) DC contained antigen, whereas only few DC from the conventional vaccine reached the LN. Interestingly, following cryo ablation the amount of antigen-loaded DC is almost doubled. Analysis of surface markers revealed that both destruction methods were able to induce DC maturation. Finally, we show that in situ tumour ablation can be efficiently combined with immune modulation by anti-CTLA-4 antibodies or regulatory T-cell depletion. These combination treatments protected mice from the outgrowth of tumour challenges, and led to in vivo enhancement of tumour-specific T-cell numbers, which produced more IFN-γ upon activation. Therefore, in situ tumour destruction in combination with immune modulation creates a unique, ‘in situ DC-vaccine' that is readily applicable in the clinic without prior knowledge of tumour antigens. PMID:16953240

  19. Successful segmental thermal ablation of varicose saphenous veins in a patient with confirmed vascular Ehlers-Danlos syndrome.

    PubMed

    Frank, Michael; Says, Jerome; Denarié, Nicolas; Sapoval, Marc; Messas, Emmanuel

    2016-04-01

    We describe here the successful scheduled treatment of varicose veins by radiofrequency segmental thermal ablation in a 43-year-old patient with vascular Ehlers-Danlos syndrome. Her venous disease started at the age of 16 years, 1 year prior to her first major Ehlers-Danlos syndrome-related event which led to the diagnosis of her genetic condition. Surgical stripping was contra-indicated because of Ehlers-Danlos syndrome at the age of 18 years. More than 20 years later, her venous disease had become highly symptomatic despite daily compression and pain medication. Venous reassessment evidenced incompetent right and left great saphenous and left small saphenous veins, with increased diameters of both sapheno-femoral and sapheno-popliteal junctions. Radiofrequency endovenous ablation rather than surgery was considered because of its minimally invasive nature and because of standardized energy delivery.All intended-to-be-treated incompetent saphenous vein segments were occluded successfully, followed by an important improvement of clinical disease severity at day 30, persistent at 1 year post-treatment. Duplex ultrasound confirmed closure and fibrotic retraction of all treated venous segments at 1 year. This report shows that radiofrequency endovenous ablation may be a safe and effective therapy of varicose veins in patients with diagnosed vascular Ehlers-Danlos syndrome.

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

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

    PubMed

    Keogh, Kenneth M; Smart, Neil J

    2016-01-01

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

  2. Feasibility of radiofrequency ablation as an alternative to surgical intervention in patients with huge multiloculated pyogenic liver abscesses

    PubMed Central

    Ke, Shan; Ding, Xue-Mei; Gao, Jun; Wang, Shao-Hong; Kong, Jian; Xu, Li; Sun, Wen-Bing

    2016-01-01

    Abstract This retrospective cohort study investigated the feasibility of radiofrequency (RF) ablation as an alternative to surgical intervention in patients with huge multiloculated pyogenic liver abscesses (PLAs). From August 2010 to April 2016, 83 patients with PLA were admitted to Beijing Chao-Yang Hospital, China. Four of these patients had huge multiloculated PLAs and underwent RF ablation plus antibiotics. The inclusion criteria for RF ablation were as follows: multiloculated PLA confirmed by computed tomography (CT) or magnetic resonance imaging (MRI), widest diameter of the PLA ≥5 cm, failure to respond to or not suitable to treatment with percutaneous drainage (PD), and patient refusal of surgery. The safety and effectiveness of RF ablation were initially assessed. All patients were commenced on antibiotics on admission to our hospital. CT-guided percutaneous catheter drainage was attempted in one patient but was unsuccessful. The main organism isolated from cultures of these patients’ blood or abscess samples was Klebsiella pneumoniae (3/4). RF ablation was performed as soon as eligibility according to the above criteria was established. RF ablation was technically successful in all 4 study patients, all PLAs being completely eradicated. The median duration of fever after RF ablation was 4.5 days. No abscesses recurred; thus, this strategy for managing PLA was 100% successful (4/4). No procedure-related deaths or major complications occurred. One patient had an asymptomatic right pleural effusion that resolved with conservative treatment including albumin infusion and diuretics. Our preliminary data indicate that RF ablation is a safe, feasible, and effective treatment for huge multiloculated PLAs. It should be considered as an alternative treatment for patients who fail to respond to or not suitable for PD plus antibiotics and refuse surgical intervention. PMID:27930527

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

    SciTech Connect

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

    2008-01-15

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2013-01-01

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

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

    SciTech Connect

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

    2011-02-15

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

  7. A methodology for constraining power in finite element modeling of radiofrequency ablation.

    PubMed

    Jiang, Yansheng; Possebon, Ricardo; Mulier, Stefaan; Wang, Chong; Chen, Feng; Feng, Yuanbo; Xia, Qian; Liu, Yewei; Yin, Ting; Oyen, Raymond; Ni, Yicheng

    2016-09-21

    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.

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

    PubMed Central

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

    2016-01-01

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

  9. Celon radiofrequency thermo-ablative palatoplasty for snoring - a pilot study.

    PubMed

    Tatla, T; Sandhu, G; Croft, C B; Kotecha, B

    2003-10-01

    A prospective non-randomized study was designed to investigate the effects of Celon radio-frequency thermo-ablation (RFTA) of the soft palate in patients with snoring/mild obstructive sleep apnoea. Ten patients, fulfilling various inclusion/exclusion criteria, underwent single operator sub-mucosal RFTA palatoplasty as an office procedure. Two separate procedures six weeks apart involved each patient receiving six distinct sub-mucosal lesions on each visit. Questionnaires including visual analogue scales (VAS) were used to evaluate post-operative pain and subjective snoring (scored by patient/partner). Polysomnography (PSG) was performed pre-operation and three months following the second procedure. Using non-parametric statistical analysis, a significant reduction in VAS snoring was noted from initial levels to those scored at six and 16 weeks in nine of 10 patients (p = 0.013 and p = 0.007 respectively). (Five of these nine showed a greater than 50 per cent reduction in score). Objectively, six of 10 patients had a reduction in the apnoea-hypopnea Index between the two PSGs, (four of these six showed a greater than 50 per cent reduction) however, this was not statistically significant. Subjective assessment of the PSG snoring signal by the senior author showed eight of 10 patients had either a reduced or much reduced signal at four months. VAS pain confirmed both procedures are well tolerated with minimal analgesia requirements. Minor complaints of transient mild palatal swelling, dry throat, catarrh and referred otalgia were noted and one patient developed mucosal ulceration following both procedures that healed within three weeks. Swallowing and speech were unaffected. These results confirm similar findings using the Somnus Unit, although the Celon device provides additional advantages including inherent safety in a bipolar electrode tip, auto-stop energy application and reduced procedure time.

  10. Radiofrequency ablation versus 125I-seed brachytherapy for painful metastases involving the bone

    PubMed Central

    Jiao, Dechao; Wu, Gang; Ren, Jianzhuang; Han, Xinwei

    2016-01-01

    This retrospective study aimed to demonstrate and compare the safety and effectiveness of computed tomography-guided radiofrequency ablation (RFA) and 125I-seed brachytherapy for painful bone metastases after failure of external beam radiotherapy (EBRT). From June 2013 to October 2015, 79 patients with moderate-to-severe pain caused by metastatic bone lesions who underwent either RFA (n = 41) or 125I-seed brachytherapy (n = 38) were enrolled. Pain in patients was measured using the brief pain inventory (BPI) before treatment, 1 week after treatment, and 3 months after treatment. Response rates were assessed by measuring the changes in pain and incorporation of changes in the analgesic requirements. At baseline, 1 week, and 3 months, the mean worst pain scores of BPI were 7.8, 5.4, and 2.7, respectively, for the RFA group and 7.7, 6.1, and 2.8, respectively, for the brachytherapy group. At 1 week, the complete and partial response rates were 12% and 59%, respectively, in the RFA group compared with 3% and 45%, respectively, in the brachytherapy group. At 3 months, the complete and partial response rates were 23% and 58%, respectively, in the RFA group compared with 24% and 52% in the brachytherapy group (p = 0.95). The response rates in the RFA group were significantly higher than those in the brachytherapy group at 1 week (p = 0.32), but comparable at 3 weeks (p = 0.95). Both groups had low rates of complications and no treatment-related mortality. In conclusion, the short-term curative efficiency of RFA was better than that of brachytherapy, but the log-term efficiency of both treatments was equal. PMID:27636995

  11. Durability and Predictors of Successful Radiofrequency Ablation for Barrett’s Esophagus

    PubMed Central

    Pasricha, Sarina; Bulsiewicz, William J.; Hathorn, Kelly E.; Komanduri, Srinadh; Muthusamy, V. Raman; Rothstein, Richard I.; Wolfsen, Herbert C.; Lightdale, Charles J.; Overholt, Bergein F.; Camara, Daniel S.; Dellon, Evan S.; Lyday, William D.; Ertan, Atilla; Chmielewski, Gary W.; Shaheen, Nicholas J.

    2014-01-01

    Background & Aims Following radiofrequency ablation (RFA), patients may experience recurrence of Barrett’s esophagus (BE) after complete eradication of intestinal metaplasia (CEIM). Rates and predictors of recurrence after successful eradication are poorly described. Methods We used the U.S. RFA Registry, a nationwide registry of BE patients receiving RFA, to determine rates and factors that predicted recurrence of IM. We assessed recurrence by Kaplan-Meier analysis for the overall cohort and by worst pretreatment histology. Characteristics associated with recurrence were included in a logistic regression model to identify independent predictors. Results Among 5521 patients, 3728 had biopsies ≥12 months after initiation of RFA. Of these, 3169 (85%) achieved CEIM, and 1634 (30%) met inclusion criteria. Average follow-up was 2.4 years after CEIM. IM recurred in 334 (20%), and was non-dysplastic or indefinite for dysplasia in 86% (287/334); the average length of recurrent BE was 0.6 cm. In Kaplan-Meier analysis, more advanced pretreatment histology was associated with an increased yearly recurrence rate. Compared to patients without recurrence, patients with recurrence were more likely, based on bi-variate analysis, to be older, have longer BE segments, be non-Caucasian, have dysplastic BE before treatment, and require more treatment sessions. In multivariate analysis, likelihood for recurrence was associated with increasing age and BE length, and non-Caucasian race. Conclusion BE recurred in 20% of patients followed for an average of 2.4 years after CEIM. Most recurrences were short segments and were non-dysplastic or indefinite for dysplasia. Older age, non-Caucasian race, and increasing length of BE length were all risk factors. These risk factors should be considered when planning post-RFA surveillance intervals. PMID:24815329

  12. Incidence of Esophageal Adenocarcinoma and Causes of Mortality in Barrett's Esophagus after Radiofrequency Ablation

    PubMed Central

    Wolf, W. Asher; Pasricha, Sarina; Cotton, Cary; Li, Nan; Triadafilopoulos, George; Muthusamy, V. Raman; Chmielewski, Gary W.; Corbett, F. Scott; Camara, Daniel S.; Lightdale, Charles J.; Wolfsen, Herbert; Chang, Kenneth J.; Overholt, Bergein F.; Pruitt, Ron E.; Ertan, Atilla; Komanduri, Srinadh; Infantolino, Anthony; Rothstein, Richard I.; Shaheen, Nicholas J.

    2016-01-01

    Background & Aims Radiofrequency ablation (RFA) is commonly used to treat Barrett's esophagus (BE). We assessed the incidence of esophageal adenocarcinoma (EAC) after RFA, predictors of EAC, and EAC-specific and all-cause mortality rates. Methods We assessed outcomes in a multicenter study of RFA for BE. Kaplan-Meier curves of EAC incidence were stratified by baseline histology. Crude EAC incidence and mortality (both all-cause and EAC-specific) rates were calculated, and adjusted all-cause mortality rates were assessed. Logistic regression models were constructed to assess predictors of EAC and all-cause mortality. Results Among 4982 patients, 100 (2%) developed EAC (7.8/1000 person-years (PY)), and 9 (0.2%) died of EAC (0.7/1000 PY) in a mean 2.7 ± 1.6 years. The incidence of EAC in non-dysplastic BE (NDBE) was 0.5/1000 PY. Overall, 157 (3%) patients died during follow-up (all-cause mortality 11.2/1000 PY). On multivariate logistic regression, baseline BE length (OR 1.1 per cm) and baseline histology (ORs of 5.8 and 50.3 for low grade dysplasia and high grade dysplasia (HGD) respectively) predicted EAC incidence. Among 9 EAC deaths, 6 (67%) had baseline HGD and 3 (33%) had baseline intramucosal EAC. The most common causes of death were cardiovascular (15%) and extra-esophageal cancers (15%). No deaths were associated with RFA. Conclusion In this multicenter registry of RFA for BE, death from EAC was rare. The incidence of EAC was markedly lower than natural history studies, with the greatest absolute benefit seen in HGD. PMID:26327132

  13. Effects of Learning Curve on Efficacy of Radiofrequency Ablation for Barrett’s Esophagus

    PubMed Central

    Pasricha, Sarina; Cotton, Cary; Hathorn, Kelly E.; Li, Nan; Bulsiewicz, William J.; Wolf, W. Asher; Muthusamy, V. Raman; Komanduri, Srinadh; Wolfsen, Herbert C.; Pruitt, Ron E.; Ertan, Atilla; Chmielewski, Gary W.; Shaheen, Nicholas J.

    2015-01-01

    Background & Aims Complete eradication of Barrett’s esophagus (BE) often requires multiple sessions of radiofrequency ablation (RFA). Little is known about the effects of case volume on the safety and efficacy of RFA, or the presence or contour of learning curves for this procedure. Methods We collected data from the US RFA Patient Registry (from 148 institutions) on patients who underwent RFA for BE from July 2007 to July 2011. We analyzed the effects of the number of patients treated by individual endoscopists and individual centers on safety and efficacy outcomes of RFA. Outcomes, including stricture, bleeding, hospitalization, and complete eradication of intestinal metaplasia (CEIM), were assessed using logistic regression. The effect of center and investigator experience on number of treatment sessions to achieve CEIM was examined using linear regression. Results After we controlled for potential confounders, we found that as case experience of endoscopists and centers increased, the numbers of treatment sessions required to achieve CEIM decreased. This relationship persisted after adjusting for patient age, sex, race, length of BE, and presence of pretreatment dysplasia (P<.01). Center experience was not significantly associated with overall rates of CEIM or complete eradication of dysplasia. We did not observe any learning curve with regard to risks of stricture, gastrointestinal bleeding, perforation, or hospitalization (P>.05). Conclusions Based on an analysis of a large multicenter registry, efficiency of the treatment, as measured by number of sessions needed to achieve CEIM, increased with case volume, indicating a learning curve effect. This trend began to disappear after treatment of approximately 30 patients by the center or individual endoscopist. However, there was no significant association between safety or efficacy outcomes and prior case volume. PMID:26116806

  14. Radiofrequency ablation suppresses distant tumour growth in a novel rat model of multifocal hepatocellular carcinoma.

    PubMed

    Erös de Bethlenfalva-Hora, Caroline; Mertens, Joachim C; Piguet, Anne-Christine; Kettenbach, Joachim; Schmitt, Johannes; Terracciano, Luigi; Weimann, Rosemarie; Dufour, Jean-François; Geier, Andreas

    2014-02-01

    RFA (radiofrequency ablation) is an established therapy for HCC (hepatocellular carcinoma). The multikinase inhibitor sorafenib prolongs survival in advanced HCC. We examined the effects of RFA alone and in combination with sorafenib on a bystanding tumour in a two-tumour rat model of HCC. A total of 80 rats were implanted with two liver tumours and randomized to four treatment groups: vehicle and sham operation (control), sorafenib and sham operation (Sora/Sham), vehicle and RFA (Vh/RFA), and sorafenib and RFA (Sora/RFA) (n=10/group per time point). RFA or sham-operation was performed on the left lobe tumour on day 15. Animals were killed at day 18 and day 30. Non-RFA-targeted right lobe tumours were analysed for angiogenesis, growth factors [HGF (hepatocyte growth factor), EGF (epidermal growth factor) and VEGF (vascular endothelial growth factor)] and infiltrating immune cells (CD3 and CD68). At day 30, the non-RFA-targeted tumours were significantly smaller in all three treatment groups compared with control (Sora/Sham P≤0.0001, Vh/RFA P=0.005 and Sora/RFA P≤0.0001). The smallest tumours were observed in animals treated with a combination of sorafenib and RFA, whereas the size reduction seen in the RFA-only group indicated an RFA-mediated distant suppression of tumour growth. Growth factor measurement revealed transiently decreased EGF levels after RFA (P=0.008), whereas sorafenib treatment decreased HGF levels (P=0.001). MVD (microvessel density) was reduced by sorafenib (P=0.002) despite increased VEGF levels (P≤0.0001). The immune parameters revealed augmented T-cells and IL-10 (interleukin 10) levels in all three treatment groups; sorafenib additionally increased macrophage numbers (P≤0.0001). RFA and sorafenib alone resulted in significant volume reduction of the non-RFA-targeted tumour; this effect was enhanced when both modalities were combined.

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

    PubMed Central

    Li, Yang; Wu, Zhong

    2016-01-01

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

  16. Effects of radiofrequency ablation on individual renal function: assessment by technetium-99m mercaptoacetyltriglycine renal scintigraphy.

    PubMed

    Mukai, Takashi; Sato, Shuhei; Iguchi, Toshihiro; Mimura, Hidefumi; Yasui, Kotaro; Gobara, Hideo; Saika, Takashi; Nasu, Yasutomo; Kumon, Hiromi; Kanazawa, Susumu

    2006-04-01

    We quantitatively evaluated total and individual renal function by technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renal scintigraphy before and after radiofrequency ablation (RFA) of renal tumors. Eleven patients who underwent Tc-99m MAG3 renal scintigraphy 1 week before and after RFA were evaluated (7 men and 4 women; age range: 23-83 years; mean age: 60.6 years). Five patients had solitary kidneys, and five had normally or minimally functioning contralateral kidneys. One patient had a renal cell carcinoma in the contralateral kidney. One patient with a solitary kidney underwent RFA a second time for a residual tumor. In patients with a solitary kidney, MAG3 clearance decreased after 5 of 6 RFAs, and in patients with a normally functioning contralateral kidney, MAG3 clearance decreased after 4 of 5 RFAs, but no significant differences were observed between before and after treatments. In addition to the total MAG3 clearance, the split MAG3 clearance was evaluated in patients with a normally functioning contralateral kidney. MAG3 clearance decreased in 4 of 5 treated kidneys, while it adversely increased in the contralateral kidneys after 4 of 5 RFAs. No significant differences, however, were observed between before and after treatments. The results of our study revealed no significant differences in sCr, BUN, CCr, or MAG3 clearance between pre- and post-RFA values. These results support data regarding the functional impact and safety of renal RFA in published reports. We evaluated total and individual renal function quantitatively using Tc-99m MAG3 renal scintigraphy before and after treatment. This scintigraphy was very useful in assessing the effects of RFA on renal function.

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

    SciTech Connect

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

    2015-04-15

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

  18. Early and Late Complications After Radiofrequency Ablation of Malignant Liver Tumors in 608 Patients

    PubMed Central

    Curley, Steven A.; Marra, Paolo; Beaty, Karen; Ellis, Lee M.; Vauthey, J Nicolas; Abdalla, Eddie K.; Scaife, Courtney; Raut, Chan; Wolff, Robert; Choi, Haesun; Loyer, Evelyne; Vallone, Paolo; Fiore, Francesco; Scordino, Fabrizio; De Rosa, Vincenzo; Orlando, Raffaele; Pignata, Sandro; Daniele, Bruno; Izzo, Francesco

    2004-01-01

    Background: Radiofrequency ablation (RFA) has become a common treatment of patients with unresectable primary and secondary hepatic malignancies. We performed this prospective analysis to determine early (within 30 days) and late (more than 30 days after) complication rates associated with hepatic tumor RFA. Methods: All patients treated between January 1, 1996 and June 30, 2002 with RFA for hepatic malignancies were entered into a prospective database. Patients were evaluated during RFA treatment, throughout the immediate post RFA course, and then every 3 months after RFA to assess for the development of treatment-related complications. Results: A total of 608 patients, 345 men (56.7%) and 263 women (43.3%), with a median age of 58 years (range 18–85 years) underwent RFA of 1225 malignant liver tumors. Open intraoperative RFA was performed in 382 patients (62.8%), while percutaneous RFA was performed in 226 (37.2%). The treatment-related mortality rate was 0.5%. Early complications developed in 43 patients (7.1%). Early complications were more likely to occur in patients treated with open RFA (33 [8.6%] of 382 patients) compared with percutaneous RFA (10 [4.4%] 226 patients, P < 0.01), and in patients with cirrhosis (25 [12.9%] complications in 194 patients) compared with noncirrhotic patients (31 [7.5%] complications in 414 patients, P < 0.05). Late complications arose in 15 patients (2.4%) with no difference in incidence between open and percutaneous RFA treatment. The combined overall early and late complication rate was 9.5%. Conclusions: Hepatic tumor RFA can be performed with low mortality and morbidity rates. Though relatively rare, late complications can develop and physicians performing hepatic RFA must be cognizant of these delayed treatment-related problems. PMID:15024305

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

    SciTech Connect

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

    2013-05-08

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

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

    SciTech Connect

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

    2013-02-15

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

  1. Long-Term Function, Pain and Medication Use Outcomes of Radiofrequency Ablation for Lumbar Facet Syndrome

    PubMed Central

    McCormick, Zachary L.; Marshall, Benjamin; Walker, Jeremy; McCarthy, Robert; Walega, David R.

    2015-01-01

    Objective Radiofrequency ablation (RFA) of the medial branch nerves for facet-mediated low back pain demonstrates clinical benefit for 6–12 months and possibly up to 2 years. This study investigated function, pain, and medication use outcomes of RFA for lumbar facet syndrome in a cohort with long-term follow-up. Methods Individuals evaluated in a tertiary academic pain practice between January, 2007–December, 2013, 18–60 years of age, with a clinical and radiologic diagnosis of lumbar facet syndrome, who underwent ≥1set of diagnostic medial branch blocks with resultant >75% pain relief and subsequent RFA were included. Outcomes measured were the proportion of individuals who reported ≥50% improvement in function, ≥50% improvement in pain; change in median NRS pain score, daily morphine equivalent consumption (DME), Medication Quantification Scale III (MSQ III) score and procedure complications. Results Sixty-two consecutive individuals with a median age and 25%–75% interquartile range (IQR) of 34 years (35, 52) met inclusion criteria. Seven individuals were lost to follow-up. Duration of pain was <2 years in 42%, 2–5 years in 40%, >5 years in 18% of individuals. Median duration of follow-up was 39 months (16, 60). Function and pain improved by ≥50% in 58% (CI 45%, 71%) and 53% (CI 40%, 66%) of individuals, respectively. The median reduction in MQS III score was 3.4 points (0, 8.8). No complications occurred in this cohort. Conclusions This study demonstrates a durable treatment effect of RFA for lumbar facet syndrome at long-term follow-up, as measured by improvement in function, pain, and analgesic use. PMID:26005713

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

    SciTech Connect

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

    2010-02-15

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

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

    PubMed Central

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

    2016-01-01

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

  4. [Ablation of accessory pathways by radiofrequency current. Towards a simplified approach of Wolff-Parkinson-White syndrome?].

    PubMed

    Atallah, G; Touboul, P; Zuloaga, C; Kirkorian, G; Lavaud, P; Moncada, E; Chevalier, P; Canu, G; Claudel, J P

    1993-06-01

    From December 1990 to April 1992, 41 consecutive patients (22 men and 19 women with an average age of 35 +/- 16 years -6-72) underwent ablation of accessory atrioventricular conduction pathways (Bundles of Kent) for poorly tolerated and/or medically resistant supraventricular tachycardias. In 33 cases, the arrhythmia was a paroxysmal SVT, in 7 cases atrial fibrillation, and in 1 patient incessant junctional tachycardia causing left ventricular dysfunction. The Wolff-Parkinson-White syndrome was apparent in 30 patients and concealed in 11 cases. The location of the Kent bundle was left lateral in 22 cases (53.7%), posterior paraseptal in 9 cases (21.9%), right lateral in 5 cases (12.2%) and anterior paraseptal in 5 cases (12.2%). The Kent bundles were ablated by radiofrequency currents in 38 cases (92.7%); in 2 patients (4.9%) in whom radiofrequency could not be used (increased impedance) high energy electrical shock was successful. In one patient (2.4%), it was not possible to suppress the Kent bundle. A single session of radiofrequency ablation was sufficient in 33 cases: 7 cases (17.5%) required 2 (4) or 3 (3) sessions. The average number of sites of application per patient was 8.8 +/- 8.8. The duration and intensity were respectively 32.2 +/- 9.3 (5-60) seconds and 25 +/- 15 (20-30) watts. With an average follow-up of tachycardia or of ventricular preexcitation have been observed in the 40 patients. In addition, in 36 patients, electrophysiological control studies confirmed the initial result with absence of any disturbance of nodohisian conduction.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Volumetric optoacoustic monitoring of endovenous laser treatments

    NASA Astrophysics Data System (ADS)

    Fehm, Thomas F.; Deán-Ben, Xosé L.; Schaur, Peter; Sroka, Ronald; Razansky, Daniel

    2016-03-01

    Chronic venous insufficiency (CVI) is one of the most common medical conditions with reported prevalence estimates as high as 30% in the adult population. Although conservative management with compression therapy may improve the symptoms associated with CVI, healing often demands invasive procedures. Besides established surgical methods like vein stripping or bypassing, endovenous laser therapy (ELT) emerged as a promising novel treatment option during the last 15 years offering multiple advantages such as less pain and faster recovery. Much of the treatment success hereby depends on monitoring of the treatment progression using clinical imaging modalities such as Doppler ultrasound. The latter however do not provide sufficient contrast, spatial resolution and three-dimensional imaging capacity which is necessary for accurate online lesion assessment during treatment. As a consequence, incidence of recanalization, lack of vessel occlusion and collateral damage remains highly variable among patients. In this study, we examined the capacity of volumetric optoacoustic tomography (VOT) for real-time monitoring of ELT using an ex-vivo ox foot model. ELT was performed on subcutaneous veins while optoacoustic signals were acquired and reconstructed in real-time and at a spatial resolution in the order of 200μm. VOT images showed spatio-temporal maps of the lesion progression, characteristics of the vessel wall, and position of the ablation fiber's tip during the pull back. It was also possible to correlate the images with the temperature elevation measured in the area adjacent to the ablation spot. We conclude that VOT is a promising tool for providing online feedback during endovenous laser therapy.

  6. Radiofrequency Ablation of Lung Tumors in Swine Assisted by a Navigation Device with Pre-procedural Volumetric Planning

    PubMed Central

    Banovac, Filip; Cheng, Patrick; Campos-Nanez, Enrique; Kallakury, Bhaskar; Popa, Teo; Wilson, Emmanuel; Abeledo, Hernan; Cleary, Kevin

    2009-01-01

    Purpose The purpose of the study was to develop an image guidance system that incorporates volumetric planning of spherical ablations and electromagnetic tracking of radiofrequency electrodes during insertion. Methods Simulated tumors were created in 3 live swine by percutaneously injecting agar nodules into the lung. A treatment plan was devised for each tumor using our optimization software to solve the planning problem. The desired output was the minimum number of overlapping ablation spheres necessary to ablate each tumor and the margin. The insertion plan was executed using the electromagnetic tracking system that guided the insertion of the probe into pre-computed locations. After a 72 hour survival, histopathologic sections of the tissue were examined for cell viability and burn pattern analysis. Results A planning algorithm to spherically cover the tumors and the margin was computed. Electromagnetic tracking allowed successful insertion of the instrument and impedance roll-off was reached in all ablations. Depending on their size, the tumors and the tumor margins were successfully covered with 2 to 4 ablation spheres. The image registration error was 1.0 ± 0.64mm. The overall error of probe insertion was 9.4 ± 3.0mm (n=8). Histopathologic sections confirmed successful ablations of the tissue. Conclusions Computer assisted RF ablation planning and electromagnetically tracked probe insertion were successful in 3 swine, thus validating the feasibility of electromagnetic tracking assisted tumor targeting. Image mis-registration due to respiratory motion and tissue deformation contributed to the overall error of probe insertion. PMID:19939704

  7. [Clinical analysis of 19 cases of pregnant women with rapid arrhythmia in the treatment of radiofrequency catheter ablation].

    PubMed

    Chu, L; Zhang, J; Li, Y N; Long, D Y

    2016-10-25

    Objective: To investigate the risk of radiofrequency catheter ablation and maternal and infant in pregnant women with rapid arrhythmia during pregnancy. Methods: The clinical data of the 19 cases of pregnancy complicated with rapid arrhythmia were retrospectively analyzed and followed up, including the gestational week, the type of arrhythmia, the treatment, and the outcome of the mother and child in Beijing Anzhen Hospital of Capital Medical University from January 2002 to March 2016. Results: (1)Clinical characteristics: the ages of the 19 cases were(31±4)years old(ranged from 26 to 35 years old), the onset gestational ages were(21±4)weeks(ranged from 15 to 32 weeks).

  8. Radiofrequency ablation for treatment for osteoid osteoma of the scapula using a new three-dimensional fluoroscopic navigation system.

    PubMed

    Okada, Kiyoshi; Myoui, Akira; Hashimoto, Nobuyuki; Takenaka, Satoshi; Moritomo, Hisao; Murase, Tsuyoshi; Yoshikawa, Hideki

    2014-02-01

    Osteoid osteoma is a relatively common benign skeletal tumor. The traditional standard treatment has been surgical resection of the nidus. Recently, computed tomography (CT)-guided radiofrequency ablation (RFA) has gained favor as a more precise alternative due to potentially less bone destruction. However, CT-guided RFA is limited in treatment for osteoid osteoma involving complex anatomic structures such as cervical spine, pelvis, or scapula because of difficulty in approach and proximity to neurovascular structures. To solve this problem, we investigated RFA using a new real-time three-dimensional fluoroscopic navigation system. We report its technical procedure and use in a rare case of osteoid osteoma of the scapula.

  9. Induction of ventricular tachycardia during radiofrequency ablation via pulmonary vein ablation catheter in a patient with an implanted pacemaker.

    PubMed

    Hammwöhner, Matthias; Stachowitz, Jörg; Willich, Tobias; Goette, Andreas

    2012-02-01

    Pulmonary vein isolation in a dual-chamber pacemaker patient using the pulmonary vein ablation catheter (PVAC) system resulted in perpetual induction of ventricular tachycardia (VT) during radio frequency energy application. Induction of VT was abolished by programming the PVAC-system to a pure bipolar ablation mode. Patients with implanted devices should be closely monitored when using the PVAC system in unipolar modes.

  10. Fiber-optic combined FPI/FBG sensors for monitoring of radiofrequency thermal ablation of liver tumors: ex vivo experiments.

    PubMed

    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.

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

    PubMed Central

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

    2016-01-01

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

  12. Sequential activation of a segmented ground pad reduces skin heating during radiofrequency tumor ablation: optimization via computational models.

    PubMed

    Schutt, David J; Haemmerich, Dieter

    2008-07-01

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

  13. The distribution of heat in bone during radiofrequency ablation of an ex vivo bovine model of osteoid osteoma.

    PubMed

    Greenberg, A; Berenstein Weyel, T; Sosna, J; Applbaum, J; Peyser, A

    2014-05-01

    Osteoid osteoma is treated primarily by radiofrequency (RF) ablation. However, there is little information about the distribution of heat in bone during the procedure and its safety. We constructed a model of osteoid osteoma to assess the distribution of heat in bone and to define the margins of safety for ablation. Cavities were drilled in cadaver bovine bones and filled with a liver homogenate to simulate the tumour matrix. Temperature-sensing probes were placed in the bone in a radial fashion away from the cavities. RF ablation was performed 107 times in tumours < 10 mm in diameter (72 of which were in cortical bone, 35 in cancellous bone), and 41 times in cortical bone with models > 10 mm in diameter. Significantly higher temperatures were found in cancellous bone than in cortical bone (p < 0.05). For lesions up to 10 mm in diameter, in both bone types, the temperature varied directly with the size of the tumour (p < 0.05), and inversely with the distance from it. Tumours of > 10 mm in diameter showed a trend similar to those of smaller lesions. No temperature rise was seen beyond 12 mm from the edge of a cortical tumour of any size. Formulae were developed to predict the expected temperature in the bone during ablation.

  14. Unintended Thermal Injuries from Radiofrequency Ablation: Organ Protection with an Angioplasty Balloon Catheter in an Animal Model

    PubMed Central

    Knuttinen, Martha-Grace; Van Ha, Thuong G.; Reilly, Christopher; Montag, Anthony; Straus, Christopher

    2014-01-01

    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 CO2 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. PMID:24678433

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

    PubMed Central

    Schutt, David J.; Haemmerich, Dieter

    2009-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  17. Effect of variable heat transfer coefficient on tissue temperature next to a large vessel during radiofrequency tumor ablation

    PubMed Central

    dos Santos, Icaro; Haemmerich, Dieter; Pinheiro, Cleber da Silva; da Rocha, Adson Ferreira

    2008-01-01

    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. PMID:18620566

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-01-01

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

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

    PubMed

    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.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2014-11-27

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

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

    PubMed Central

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

    2016-01-01

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

  4. Treatment efficacy and safety of ultrasound-guided percutaneous bipolar radiofrequency ablation for benign thyroid nodules

    PubMed Central

    Li, Xiao-long; Lu, Feng; Yue, Wen-wen; Sun, Li-ping; Bo, Xiao-wan; Guo, Le-hang; Xu, Jun-mei; Liu, Bo-ji; Li, Dan-dan; Qu, Shen

    2016-01-01

    Objective: To evaluate the therapeutic efficacy and safety of ultrasound-guided percutaneous bipolar radiofrequency ablation (BRFA) of benign thyroid nodules by comparison with a matched untreated control group. Methods: The therapeutic efficacy and safety in 35 patients who were subjected to a single session of ultrasound-guided percutaneous BRFA (Group A) for benign thyroid nodules were compared with those in 35 untreated patients (Group B) with benign nodules. The benign nature of all the nodules was confirmed by ultrasound-guided fine-needle aspiration biopsy (FNAB), and all the patients had normal thyroid functions. BRFA was performed with a bipolar electrode (CelonProSurge 150–T20) with an output power of 20 W. Nodule volume, thyroid function and clinical symptoms of all the patients were compared before treatment and during follow-up. Results: In Group A, the BRFA procedures were completed with a mean time of 10.02 ± 3.30 min (range, 5.47–16.03 min) and with a mean total energy deposition of 10.747 ± 3704 J (range, 5510–17.770 J). The procedures were tolerated well in all the patients without causing any major complications. At the 6-month follow-up, all of the nodule volume decreased significantly (from 8.81 ± 8.66 to 1.59 ± 1.55 ml, p < 0.001) in Group A, whereas the nodule volume increased from 6.90 ± 3.77 to 7.87 ± 3.95 ml in Group B (p < 0.001). All (100%) the 35 nodules in Group A had volume reduction ratios (VRRs) of >50%, among which 3 (8.57%) had VRRs >90%. In Group A, the clinical symptoms of the patients who had symptoms before BRFA disappeared, whereas in Group B, the patients had no resolution of clinical symptoms at the 6-month follow-up. Conclusion: Ultrasound-guided percutaneous BRFA seems to be an effective and safe method for the treatment of benign thyroid nodules. It may gain a wide use in clinical practice. Advances in knowledge: Based on the comparable efficacy and clinical

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

    PubMed

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

    2016-09-01

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

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

    PubMed Central

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

    2016-01-01

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

  7. Evaluation of the safety and efficacy of radiofrequency ablation for treating benign thyroid nodules

    PubMed Central

    Tang, Xiaoyin; Cui, Dan; Chi, Jiachang; Wang, Zhi; Wang, Tao; Zhai, Bo; Li, Ping

    2017-01-01

    Background: Radiofrequency ablation (RFA) is a relatively new procedure for treating benign thyroid nodules. The purpose of this study was to evaluate the safety and efficacy of RFA for treating benign thyroid nodules so as to serve as a reference for future clinical practice. Methods: This study retrospectively analyzed the clinical data of patients receiving percutaneous RFA for treating thyroid nodules from November 2014 to July 2015 in our medical center. One hundred and eight patients with a total of 380 nodules received ultrasound-guided RFA for treating thyroid nodules. Comparisons of the volume change of thyroid nodules before and after RFA treatment, post-treatment complication, and change of thyroid function, were carried out afterwards. Results: Before treatments, all patients received fine needle aspiration biopsy (FNA) which supported the diagnosis of benign tumor. There were 13 males and 95 females included in the study. Twenty-six cases (24.07%) had single nodule, and 82 cases (75.93%) had multiple nodules. Before treatments, the thyroid functions (FT3, FT4, and TSH) were normal originally or adjusted to normal range by endocrinology treatment. The preoperative nodules had minimum volume of 0.01mL, maximum volume of 70.89 mL, and mean volume of 1.02 ± 4.24mL. The volume of nodules one month and three months after RFA were 0.29 ± 0.72mL and 0.15 ± 0.87mL, respectively. In addition, volume reduction ratio (VRR) of nodules one month and three months after RFA were 64.12% and 85.54%, respectively. Both volume of nodules and VRR had statistically significant differences for pre-operative and post-operative comparison (P<0.05). Thyroid functions were in normal range after treatments, and there was no serious complications. Conclusions: Ultrasound-guided RFA treating benign thyroid nodules had the advantages of definite efficacy, safety, strong in control ability, no incision, less damage to surrounding normal tissues and no effect on thyroid function

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

    PubMed Central

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

    2013-01-01

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

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

    PubMed

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

    2016-08-01

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

  10. Radiofrequency Ablation in Combination with Embolization in Metachronous Recurrent Renal Cancer in Solitary Kidney after Contralateral Tumor Nephrectomy

    SciTech Connect

    Gebauer, Bernhard Werk, Michael; Lopez-Haenninen, Enrique; Felix, Roland; Althaus, Peter

    2007-07-15

    Purpose. To evaluate the feasibility and safety of minimally invasive, percutaneous techniques in metachronous recurrent renal cell cancers (RCCs) in solitary kidneys. Methods. In 4 patients, recurrent RCC was treated by radiofrequency ablation (RFA) (RITA, StarBurst) alone, and in 2 patients by RFA in combination with superselective transarterial particle-lipiodol embolization using 3 Fr microcatheters. RFA was guided by computed tomography in 5 patients, and by magnetic resonance imaging in 1 patient. Mean tumor diameter was 26.7 mm (range 10-45 mm). All interventions were technically successful; during follow-up 1 patient developed recurrent RCC, which was retreated by RFA after embolization. Results. No major peri- or postprocedural complications occurred. Changes in creatinine (pre- vs. post-intervention, 122 vs. 127 {mu}mol/l) and calculated creatinine clearance (pre- vs. post-intervention, 78 vs. 73 ml/min) after ablation were minimal. Conclusion. In single kidneys, percutaneous, minimally invasive techniques are safe and feasible. In large tumors, or where there are adjacent critical structures, we prefer a combination of embolization and thermal ablation (RFA)

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

    SciTech Connect

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

    2013-07-11

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

  12. Randomized trial of radiofrequency ablation versus conventional surgery for superficial venous insufficiency: if you don’t tell, they won’t know

    PubMed Central

    de Almeida Mendes, Cynthia; de Arruda Martins, Alexandre; Fukuda, Juliana Maria; Parente, José Ben-Hur Ferraz; Munia, Marco Antonio Soares; Fioranelli, Alexandre; Teivelis, Marcelo Passos; Varella, Andrea Yasbek Monteiro; Caffaro, Roberto Augusto; Kuzniec, Sergio; Wolosker, Nelson

    2016-01-01

    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 assessments

  13. Toward modeling of radio-frequency ablation lesions for image-guided left atrial fibrillation therapy: model formulation and preliminary evaluation.

    PubMed

    Linte, Cristian A; Camp, Jon J; Holmes, David R; Rettmann, Maryam E; Packer, Douglas L; Robb, Richard A

    2013-01-01

    In the context of image-guided left atrial fibrillation therapy, relatively very little work has been done to consider the changes that occur in the tissue during ablation in order to monitor therapy delivery. Here we describe a technique to predict the lesion progression and monitor the radio-frequency energy delivery via a thermal ablation model that uses heat transfer principles to estimate the tissue temperature distribution and resulting lesion. A preliminary evaluation of the model was conducted in ex vivo skeletal beef muscle tissue while emulating a clinically relevant tissue ablation protocol. The predicted temperature distribution within the tissue was assessed against that measured directly using fiberoptic temperature probes and showed agreement within 5°C between the model-predicted and experimentally measured tissue temperatures at prescribed locations. We believe this technique is capable of providing reasonably accurate representations of the tissue response to radio-frequency energy delivery.

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

    PubMed

    Seror, O

    2015-06-01

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

  15. A Newly Developed Perfused Umbrella Electrode for Radiofrequency Ablation: An Ex Vivo Evaluation Study in Bovine Liver

    SciTech Connect

    Bruners, Philipp Pfeffer, Jochen; Kazim, Rana M.; Guenther, Rolf W.; Schmitz-Rode, Thomas; Mahnken, Andreas H.

    2007-09-15

    The purpose of this study was to evaluate the effectiveness of a newly developed perfused monopolar radiofrequency (RF) probe with an umbrella-shaped array. A perfused umbrella-shaped monopolar RF probe based on a LeVeen electrode (Boston Scientific Corp., Natick, MA, USA) with a 3-cm array diameter was developed. Five different configurations of this electrode were tested: (a) perfusion channel/endhole, (b) perfusion channel/endhole + sideholes, (c) 1 cm insulation removed at the tip, (d) 1 cm insulation removed at the tip + perfusion channel/endhole, and (e) 1 cm insulation removed at the tip + perfusion channel/endhole + sideholes. An unmodified LeVeen electrode served as a reference standard. RF ablations were performed in freshly excised bovine liver using a commercial monopolar RF system with a 200-W generator (RF 3000; Boston Scientific Corp.). Each electrode was tested 10 times applying the vendor's recommended ablation protocol combined with the preinjection of 2 ml 0.9% saline. Volumes and shapes of the lesions were compared. Lesions generated with the original LeVeen electrode showed a mean volume of 12.74 {+-} 0.52 cm{sup 3}. Removing parts of the insulation led to larger coagulation volumes (22.65 {+-} 2.12 cm{sup 3}). Depending on the configuration, saline preinjection resulted in a further increase in coagulation volume (25.22 {+-} 3.37 to 31.28 {+-} 2.32 cm{sup 3}). Besides lesion volume, the shape of the ablation zone was influenced by the configuration of the electrode used. We conclude that saline preinjection in combination with increasing the active tip length of the umbrella-shaped LeVeen RF probe allows the reliable ablation of larger volumes in comparison to the originally configured electrode.

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

    PubMed Central

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

    2015-01-01

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

  17. Post-operative pericardial effusion following treatment of small hepatocellular carcinoma with radiofrequency ablation: A case report.

    PubMed

    Zhang, Zhebo; Zhuang, Zhuonan; Xu, Zhenjie; Mei, Qiang; Ma, Kuansheng; Li, Xiaowu; Bie, Ping

    2014-02-01

    Radiofrequency ablation (RFA) is a minimally invasive technique used to treat liver tumors. The current study presents the case of a patient with hepatocellular carcinoma who suffered from post-operative pericardial effusion following RFA treatment. We hypothesize that RFA thermal conduction may damage the diaphragm and pericardium, leading to local edema in the pericardium. RFA is a minimally invasive technique, however, adequate preparatory work must be performed prior to surgery, including a comprehensive assessment of the patient. During surgery, the location and extent of the region to receive RFA must be determined precisely in order to reduce the range of damage and to avoid post-operative complications. This study describes a case of pericardial effusion caused by RFA of liver cancer. We analyzed the causes and preventive measures for pericardial effusion in order to contribute to the prevention pericardial effusion that is complicated by RFA of liver cancer.

  18. Endomedullary radiofrequency ablation of metastatic lesion of the right femur 5 years after primary breast carcinoma: a case report.

    PubMed

    Majerović, Mate; Augustin, Goran; Jelincić, Zeljko; Buković, Damir; Burcar, Ivan; Smud, Dubravko; Kekez, Tihomir; Kinda, Emil; Matosević, Petar; Turcić, Josip

    2008-12-01

    Metastatic tumors of the long bones usually present with severe pain refractory to analgesic therapy. Pathologic fractures of the bone may lead to the significant decrease of patient's quality of life and necessitate further surgical therapy. We present 66 year old female with metastatic left breast carcinoma (T2N0M0) diagnosed 5 years before presentation of the metastatic lesion of the right femur causing severe pain in the middle of the right upper leg. Pain persisted after palliative irradiation therapy. We performed radiofrequency ablation of the metastatic lesion of the right femur using R.I.TA. Medical System Generator. This resulted in total necrosis of the tumor mass that caused osteolysis of the internal part of the femoral cortex. First three months after RFA procedure, the pain and tenderness were absent and normal daily activities were performed without restrictions.

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

    PubMed Central

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

    2015-01-01

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

  20. Adrenal-preserving minimally invasive surgery: the role of laparoscopic partial adrenalectomy, cryosurgery, and radiofrequency ablation of the adrenal gland.

    PubMed

    Munver, Ravi; Del Pizzo, Joseph J; Sosa, R Ernest

    2003-02-01

    Adrenalectomy has become the standard of care for the management of hormonally active adrenal masses. Various surgical therapies have been proposed to excise completely or destroy these adrenal lesions, which may be benign or malignant. New minimally invasive, adrenal-sparing procedures have recently been introduced, among them laparoscopic partial adrenalectomy, cryosurgery, and radiofrequency ablation. These procedures focus on reducing patient morbidity and hastening postoperative recovery while preserving normal adrenal tissue. However, questions remain about the risks and benefits associated with routine application of minimally invasive therapies for adrenal-sparing surgery in terms of complete tumor extirpation. Clearly, more experience and longer follow-up is necessary to validate these procedures. Herein we describe the surgical techniques and early results of treatment with adrenal-sparing surgery.

  1. Technique for creation of artificial pneumothorax for pain relief during radiofrequency ablation of peripheral lung tumors: report of seven cases.

    PubMed

    Hiraki, Takao; Gobara, Hideo; Shibamoto, Kentaro; Mimura, Hidefumi; Soda, Yuko; Uka, Mayu; Masaoka, Yoshihisa; Toyooka, Shinichi; Kanazawa, Susumu

    2011-04-01

    This report describes seven cases in which a pneumothorax was artificially created for relief from severe pain that occurred during radiofrequency (RF) ablation of peripheral lung tumors. In this procedure, the multitined probe surrounding the lesion was advanced into the chest, displacing the tines and the peripheral tumor away from the parietal pleura and the chest wall and resulting in pain relief in one patient; in the remaining patients, an intravenous catheter was also introduced, followed by the administration of carbon dioxide (CO(2)) into the space between the tumor and the parietal pleura. The pain decreased considerably immediately after this procedure. No complication related to the creation of the artificial pneumothorax was observed. Creation of an artificial pneumothorax is a safe and effective method for pain relief.

  2. Analytical validation of COMSOL Multiphysics for theoretical models of Radiofrequency ablation including the Hyperbolic Bioheat transfer equation.

    PubMed

    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.

  3. Effectiveness of various thermal ablation techniques for the treatment of nodular thyroid disease--comparison of laser-induced thermotherapy and bipolar radiofrequency ablation.

    PubMed

    Ritz, Jörg-Peter; Lehmann, Kai S; Schumann, Thomas; Knappe, Verena; Zurbuchen, Urte; Buhr, Heinz J; Holmer, Christoph

    2011-07-01

    Alternative minimally invasive treatment options such as radiofrequency ablation (RFA) or laser-induced thermotherapy (LITT) are at present under investigation for achieving a nonsurgical targeted cytoreduction in benign and malignant thyroid lesions. So far, studies have not been able to show a secure advantage for neither LITT nor RFA. The aim of this study was to compare the two ablation procedures in terms of their effectiveness. Thermal lesions were induced in porcine thyroid glands either by LITT or bipolar RFA ex vivo (n = 110 each) and in vivo (n = 10 each) using power settings between 10 and 20 W. Temperature spread during application was documented in 5- and 10-mm distance of the applicator. Postinterventional lesion diameters were measured and lesion size was calculated. Furthermore, enzyme histochemical analysis of the thyroid tissue was performed in vivo. Lesion volumes induced by LITT ranged between 0.74 ± 0.18 cm(3) (10 W) and 3.80 ± 0.41 cm(3) (20 W) with a maximum of 5.13 ± 0.16 cm(3) at 18 W. The inducible lesion volumes by RFA were between 2.43 ± 0.68 cm(3) (10 W) and 0.91 ± 0.71 cm(3) (20 W) with a maximum of 2.80 ± 0.85 cm(3) at 14 W. The maximum temperatures were 112.9 ± 9.2°C (LITT) and 61.6 ± 13.9°C (RFA) at a distance of 5 mm and 73.2 ± 6.7°C (LITT) and 53.5 ± 8.6°C (RFA) at a distance of 10 mm. The histochemical analysis demonstrates a complete loss of NADPH dehydrogenase activity in thermal lesions as a sign of irreversible cell damage both for LITT and RFA. This study is the first to compare the effectiveness of laser-induced thermotherapy and radiofrequency ablation of thyroid tissue. LITT as well as RFA are suitable for singular thyroid nodules and induces reproducible clinically relevant lesions in an appropriate application time. The maximum inducible lesion volumes by LITT are significantly larger than by RFA with the devices used herein.

  4. Percutaneous tumor ablation tools: microwave, radiofrequency, or cryoablation--what should you use and why?

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2013-11-01

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

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

    PubMed

    Smith, S L; Jennings, P E

    2015-02-01

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

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

    PubMed Central

    Wiest, Jennifer H.; Buckner, Gregory D.

    2014-01-01

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

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

    PubMed Central

    Jennings, P E

    2015-01-01

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

  10. Post-Ablation Endometrial Carcinoma (PAEC) Following Radiofrequency Endometrial Ablation: A Case Report and Its Implications for Management of Endometrial Ablation Failures.

    PubMed

    Wortman, Morris; Dawkins, Josette C

    2016-10-26

    Endometrial ablation (EA) has become one of the most commonly performed gynecologic procedures in the United States and other developed countries. Global endometrial ablation (GEA) devices have supplanted resectoscopic ablation primarily because they have brought with them technical simplicity and unprecedented safety. These devices, all of which received FDA approval between 1997 and 2001, are typically used to treat abnormal uterine bleeding (AUB) in premenopausal women. Several million women in the US who have undergone a previous EA procedure are about to enter the risk pool for the development of endometrial cancer (EC). Ours is the 18th reported case of post-ablation endometrial carcinoma (PAEC) in the English literature. This case underscores the diagnostic challenges faced in evaluating women with a history of a previous EA who cannot be properly evaluated with conventional techniques such as endometrial biopsy and sonohysterography.

  11. Image-based multi-scale modelling and validation of radio-frequency ablation in liver tumours.

    PubMed

    Payne, Stephen; Flanagan, Ronan; Pollari, Mika; Alhonnoro, Tuomas; Bost, Claire; O'Neill, David; Peng, Tingying; Stiegler, Philipp

    2011-11-13

    The treatment of cancerous tumours in the liver remains clinically challenging, despite the wide range of treatment possibilities, including radio-frequency ablation (RFA), high-intensity focused ultrasound and resection, which are currently available. Each has its own advantages and disadvantages. For non- or minimally invasive modalities, such as RFA, considered here, it is difficult to monitor the treatment in vivo. This is particularly problematic in the liver, where large blood vessels act as heat sinks, dissipating delivered heat and shrinking the size of the lesion (the volume damaged by the heat treatment) locally; considerable experience is needed on the part of the clinician to optimize the heat treatment to prevent recurrence. In this paper, we outline our work towards developing a simulation tool kit that could be used both to optimize treatment protocols in advance and to train the less-experienced clinicians for RFA treatment of liver tumours. This tool is based on a comprehensive mathematical model of bio-heat transfer and cell death. We show how simulations of ablations in two pigs, based on individualized imaging data, compare directly with experimentally measured lesion sizes and discuss the likely sources of error and routes towards clinical implementation. This is the first time that such a 'loop' of mathematical modelling and experimental validation in vivo has been performed in this context, and such validation enables us to make quantitative estimates of error.

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

    PubMed

    Yan, Shengjie; Wu, Xiaomei; Wang, Weiqi

    2016-05-01

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

  13. A preliminary study of the safety and efficacy of radiofrequency ablation with percutaneous kyphoplasty for thoracolumbar vertebral metastatic tumor treatment

    PubMed Central

    Zheng, Longpo; Chen, Zhengqi; Sun, Mengxiong; Zeng, Hui; Zuo, Dongqing; Hua, Yingqi; Cai, Zhengdong

    2014-01-01

    Background Thoracolumbar vertebral metastasis (TVM) affects a large number of cancer patients. However, safe and effective palliative care remains controversial. The aim of the present study was to investigate the safety and efficacy of minimally invasive image-guided radiofrequency ablation (RFA) with percutaneous kyphoplasty (PKP) for TVM treatment. Material/Methods A retrospective study of 26 patients (mean age: 59.31±11.62 years) was conducted, including 38 vertebral metastases at T11, T12, L1, L2, L3, L4, L5, and S1 with abundant blood vessels. Patients underwent RFA with PKP (4–6 min, 95±5°C, 150 W, effective electrode area of 1.5–2.0 cm) under general anesthesia from February 2005 to January 2009. Electrodes were inserted into the lesions and pre- and post-operative visual analog scale (VAS) scores and X-rays were collected on day 3, week 1, and months 1, 3, and 6. Tumor recurrence and pain level were also evaluated. Safety assessment was conducted based on complications and adverse events. The mean follow-up time was 8.4±2.1 months. Results A mean of 2.69±0.93 ablation was performed per patient. The ablation procedure required a mean of 15.08±4.64 min, while the injection of bone cement required a mean of 6.73±0.83 min, for a mean total operating time of 47.77±7.13 min. Postoperative VAS scores were significantly lower on day 3, week 1, and months 1, 3, and 6 (P<0.01), without any complications or tumor recurrence. Conclusions Image-guided RFA with PKP was safe and effective for TVM treatment when used with careful consideration of bone cement volume/viscosity, injection location, and temperature. PMID:24699431

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

    SciTech Connect

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

    2009-01-15

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

  15. Effect of sequential radiofrequency ablation lesions at fast and slow atrioventricular nodal pathway positions in patients with paroxysmal atrial fibrillation.

    PubMed Central

    Garratt, C. J.; Skehan, J. D.; Payne, G. E.; Stafford, P. J.

    1996-01-01

    OBJECTIVE: To examine the hypothesis that the anatomic equivalents of the fast and slow pathways identified in patients with atrioventricular (AV) nodal tachycardia may be universal and represent the principal sites of atrial input into the normal compact AV node. METHODS: 15 patients undergoing complete AV junction ablation for paroxysmal atrial fibrillation were studied. Radiofrequency energy was delivered first in the anterior "fast pathway" position so as to prolong the atrium to bundle of His (AH) interval by over 50% of baseline (protocol 1) and then to the "slow pathway" position using the anatomical technique (protocol 2). RESULTS: Ablation protocol 1 resulted in prolongation of AH interval in all patients. Subsequent lesions at the level of the coronary sinus produced complete heart block in four patients, and in five caused a further increase in AH interval above that produced by protocol 1. Four of these latter patients developed complete block after delivery of RF energy slightly anterior to the level of the coronary sinus os, as did three further patients in whom ablation at the level of the coronary sinus had no effect. In four patients complete heart block could not be achieved by protocol 2. CONCLUSIONS: A discrete anterior "fast" pathway and a posterior "slow" pathway or network of posterior pathways form the principal inputs to the compact AV node in most patients with atrial fibrillation. The absence of dual AV nodal physiology in the majority of these patients may be related to the functional properties of the individual components of this posterior network. PMID:8665345

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

    SciTech Connect

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

    2012-06-15

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

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

    PubMed

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

    2016-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2005-04-01

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

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

    PubMed

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

    2003-07-01

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

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

    PubMed Central

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

    2016-01-01

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

  1. Sequential activation of ground pads reduces skin heating during radiofrequency tumor ablation: in vivo porcine results.

    PubMed

    Schutt, David J; Swindle, M Michael; Helke, Kristi L; Bastarrika, Gorka; Schwarz, Florian; Haemmerich, Dieter

    2010-03-01

    Skin burns below ground pads during monopolar RF ablation are increasingly prevalent, thereby hindering the development of higher power RF generators capable of creating larger tumor ablation zones in combination with multiple or new applicators. Our goal was to evaluate reduction in skin temperatures via additional ground pads in an in vivo porcine model. Three ground pads placed on the animal's abdomen were activated either simultaneously or sequentially, where activation timing was adjusted to equilibrate skin temperature below each pad. Thirteen RF ablations (n = 4 simultaneous at 300 W, n = 5 sequential at 300 W, and n = 4 sequential at 375 W) were performed for 12 min via two internally cooled cluster electrodes placed in the gluteus maximus of domestic swine. Temperature rise at each pad and burn degree as determined via histology were compared. Ablation zone size was determined via T2-weighted MRI. Maximum temperature rise was significantly higher with simultaneous activation than with either of the sequential activation group (21.4 degrees C versus 8.1 degrees C or 9.6 degrees C, p < 0.01). Ablation zone diameters during simultaneous (300 W) and sequential activations (300 and 375 W) were and 6.9 +/- 0.3, 5.6 +/- 0.3, and 7.5 +/- 0.6 cm, respectively. Sequential activation of multiple ground pads results in significantly lower skin temperatures and less severe burns, as measured by histological examination.

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

    SciTech Connect

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

    2007-04-15

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

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

    SciTech Connect

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

    2006-12-15

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

  4. Use of intra-arterial carbon-dioxide-enhanced ultrasonography for guidance of radiofrequency ablation and transcatheter arterial chemoembolization in hepatocellular carcinoma.

    PubMed

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

    2006-01-01

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

  5. Fusion of Delayed-enhancement MR Imaging and Contrast-enhanced MR Angiography to Visualize Radiofrequency Ablation Scar on the Pulmonary Vein.

    PubMed

    Shigenaga, Yutaka; Kiuchi, Kunihiko; Ikeuchi, Kazushi; Ikeda, Takayuki; Okajima, Katsunori; Yasaka, Yoshinori; Kawai, Hiroya

    2015-01-01

    Delayed-enhancement magnetic resonance imaging (DE-MRI) is reported to detect the radiofrequency (RF) ablation scar of pulmonary vein isolation. However, the precise localization of RF scar is difficult to recognize due to the poor anatomical information of the 3-dimensionally reconstructed DE-MRI. We report 2 cases in which fusion of DE-MRI and contrast-enhanced MR angiography facilitated the identification of RF scar, and we detail our fusion method.

  6. [The influence of radiofrequency thermal ablation on the clinical course of hypertrophic rhinitis and histomorphology of the inferior turbinated bones].

    PubMed

    Talyshinskiĭ, A A; Siutaĭ, Semikh; Ozogul, Dzhandal; Talyshinskiĭ, A M

    2013-01-01

    The objective of the present work was to study the influence of radiofrequency thermal ablation (RFTA) of the inferior turbinated bones on the main functions of the nasal cavity in the patients suffering hypertrophic rhinitis. The secondary objective was to elucidate the histomorphological features of the inferior turbinated bones. A total of 40 patients presenting with nasal breathing disorders associated with the inferior turbinated bone hypertrophy were available for the examination. This work was supplemented by an experimental study with the use of rabbit the inferior turbinated bones. The influence of radiofrequency thermal energy on the hypertrophic the inferior turbinated bones was estimated based on dynamics of clinical symptoms and functional state of the nasal cavity before and after its application. The patients' complaints and the results of the objective evaluation were analysed and compared with the help of the visual-analog scale (VAS) before and 1-8 weeks after RFTA. The study has demonstrated that the size of the inferior turbinated bones and the severity of nasal obstruction significantly decreased within 28 days after RFTA whereas the patients' complaints of nasal stiffness and difficulty of nasal breathing totally disappeared. The inferior turbinated bones of the rabbits underwent a marked reduction of density and cilia growth in conjunction with the thickening of the basal membrane and the onset of subepithelial fibrosis within 7 days after RFTA. The structure of basal membrane was virtually normalized within 28 days after RFTA simultaneously with a rise in the number of cilia and the enhancement of their growth. It is concluded that the results of clinical and experimental studies give reason to consider RFTA as an effective method for the treatment of nasal stiffness caused by hypertrophy of the inferior turbinated bones. RFTA induces subepithelial fibrosis and thereby promotes the decrease of the inferior turbinated bone volume in the

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  8. Perinodal slow potential as a local guide for transcatheter radiofrequency ablation of atrioventricular nodal reentrant tachycardia: therapeutic efficacy and electrophysiological mechanisms of success.

    PubMed Central

    Lin, J. L.; Lin, F. Y.; Lo, H. M.; Tseng, C. D.; Cheng, T. F.; Chen, J. J.; Tseng, Y. Z.; Lien, W. P.

    1995-01-01

    BACKGROUND--A specific local indicator in the Koch's triangle could be critical to the complication-free treatment of atrioventricular nodal reentrant tachycardia by transcatheter radiofrequency ablation. Recording of perinodal slow potential reflects a slow conduction area, and probably indicates the location of the slow pathway component of the circuit. Specific ablation of the slow pathway would carry the least risk of atrioventricular block. METHOD AND RESULTS--Guided by the mapped perinodal slow potential, atrioventricular nodal reentrant tachycardia was successfully eliminated in all of 55 consecutive patients in one session. Fifty two patients (94.5%) had confirmed slow potential at the final success sites. Despite the good result, the underlying electrophysiological mechanisms of early success from slow-potential-guiding catheter ablation were heterogeneous: selective slow pathway eradication in 31 patients (56.4%, group A), selective slow pathway modification in 18 patients (32.7%, group B), inadvertent fast pathway damage in six patients (10.9%, group C). Group B patients had the preservation of dual atrioventricular nodal pathways, adequate atrio-Hisian delay, fast pathway facilitation, and a higher frequency of inducible, single non-conducted nodal echo (15/18, 83.3% v 6/31, 19.4% in group A, P << 0.001). The upper communicating path of the circuit was implicated as another site of radiofrequency destruction. Three recurrences were documented in follow up study. However, reablation by the same approach caused complete atrioventricular block in one patient (1.7%, 1/58 procedures). None of the local characteristics of ablation sites was an independent predictor of procedure outcome. CONCLUSIONS--Perinodal slow potential is not a specific slow pathway indicator in transcatheter radiofrequency ablation of atrioventricular nodal reentrant tachycardia. Multiple strategic sites of the reentry circuit may be damaged through similar local signals. PMID:7547021

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

    SciTech Connect

    Andreano, Anita; Brace, Christopher L.

    2013-04-15

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

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

    PubMed Central

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

    2015-01-01

    Abstract The location of the caudate lobe and its complex anatomy make caudate lobectomy and radiofrequency ablation (RFA) under ultrasound guidance technically challenging. The objective of the exploratory study was to introduce a novel modality of treatment of lesions in caudate lobe and discuss all details with our experiences to make this novel treatment modality repeatable and educational. The study enrolled 39 patients with liver caudate lobe tumor first diagnosed by computerized tomography (CT) or magnetic resonance imaging (MRI). After consultation of multi-disciplinary team, 7 patients with hepatic caudate lobe lesions were enrolled and accepted CT-guided percutaneous step-by-step RFA treatment. A total of 8 caudate lobe lesions of the 7 patients were treated by RFA in 6 cases and RFA combined with percutaneous ethanol injection (PEI) in 1 case. Median tumor diameter was 29 mm (range, 18–69 mm). A right approach was selected for 6 patients and a dorsal approach for 1 patient. Median operative time was 64 min (range, 59–102 min). Median blood loss was 10 mL (range, 8-16 mL) and mainly due to puncture injury. Median hospitalization time was 4 days (range, 2–5 days). All lesions were completely ablated (8/8; 100%) and no recurrence at the site of previous RFA was observed during median 8 months follow-up (range 3–11 months). No major or life-threatening complications or deaths occurred. In conclusion, percutaneous step-by-step RFA under CT guidance is a novel and effective minimally invasive therapy for hepatic caudate lobe lesions with well repeatability. PMID:26426638

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

    SciTech Connect

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

    2015-08-15

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

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

    SciTech Connect

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

    2012-12-15

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

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

    PubMed Central

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

    2015-01-01

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

  14. Safety and Efficacy of Switching Anticoagulation to Aspirin Three Months after Successful Radiofrequency Catheter Ablation of Atrial Fibrillation

    PubMed Central

    Uhm, Jae-Sun; Won, Hoyoun; Joung, Boyoung; Nam, Gi-Byoung; Choi, Kee-Joon; Lee, Moon-Hyoung; Kim, You-Ho

    2014-01-01

    Purpose Although current guidelines recommend continuing the same antithrombotic strategy regardless of rhythm control after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF), anticoagulation has a risk of major bleeding. We evaluated the safety of switching warfarin to aspirin in patients with successful AF ablation. Materials and Methods Among 721 patients who underwent RFCA of AF, 608 patients (age, 57.3±10.9 years; 77.0% male, 75.5% paroxysmal AF) who had no evidence of AF recurrence at 3 months post-RFCA were included. We compared the thromboembolic and hemorrhagic events in patients for whom warfarin was switched to aspirin (ASA group; n=296) and patients who were kept on warfarin therapy (W group; n=312). Results There were no significant differences in CHA2DS2-VASc or HAS-BLED scores between the groups. In 30 patients in the ASA group and 37 patients in W group, AF recurred and warfarin was restarted or maintained during the 18.0±12.2 months of follow-up. There were no significant differences in thromboembolic (0.3% vs. 1.0%, p=0.342) and major bleeding incidences (0.7% vs. 0.6%, p=0.958) between ASA and W groups during the follow-up period. In the 259 patients with a CHA2DS2-VASc score ≥2, there were no significant differences in thromboembolism (0.8% and 2.2%, p=0.380) or major bleeding incidences (0.8% and 1.4%, p=0.640) between ASA and W groups. Conclusion Switching warfarin to aspirin 3 months after successful RFCA of AF could be as safe and efficacious as long-term anticoagulation even in patients with CHA2DS2-VASc score ≥2. However, strict rhythm monitoring cannot be overemphasized. PMID:25048480

  15. The Role of Intravenous Dopamine on Hemodynamic Support during Radiofrequency Catheter Ablation of Poorly Tolerated Idiopathic Ventricular Tachycardia

    PubMed Central

    Ahn, Jinhee; Kim, Dong-Hyeok; Roh, Seung-Young; Lee, Kwang No; Lee, Dae-In; Shim, Jaemin; Choi, Jong-Il

    2017-01-01

    Background and Objectives Hemodynamically unstable idiopathic ventricular tachycardias (VTs) are a challenge for activation or entrainment mapping technique. Mechanical circulatory support is an option, but is not always readily available. In this study, we investigated the safety and efficacy of hemodynamic support using intravenous (IV) dopamine solely during radiofrequency catheter ablation (RFCA) of hemodynamically unstable VT. Subjects and Methods Seven out of 86 patients with hemodynamically unstable idiopathic VT underwent de novo RFCA using dopamine in our single center. They were included in the study and reviewed retrospectively to investigate the procedural characteristics and outcomes. Results All patients were male, and the mean age was 50.7±5.3 years. One patient had implantable cardioverter-defibrillator for the secondary prevention. No evidence of myocardial ischemia was found in all patients. During the procedure, the mean blood pressure during VT without dopamine was 52.3±4.1 mmHg and increased to 82.6±3.8 mmHg after administering dopamine (Δ28.8±3.2 mmHg; total average dopamine dosage was 1266.1±389.6 mcg/kg). In all patients, activation mapping was safely applied, and VTs were terminated during energy delivery. Non-inducibility of clinical VT was achieved in all cases. There was no evidence of deterioration due to hypoperfusion during the peri-procedural period. No recurrence of ventricular tachyarrhythmias was observed in any of the patients, during a median follow-up of 23.0±6.1 months. Conclusion Hemodynamic support using IV dopamine during RFCA of hemodynamically unstable idiopathic VT facilitated detailed mapping to guide successful ablation. PMID:28154593

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

    PubMed Central

    2013-01-01

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  19. Ultrasound-guided alcohol neurolysis and radiofrequency ablation of painful stump neuroma: effective treatments for post-amputation pain

    PubMed Central

    Zhang, Xin; Xu, Yongming; Zhou, Jin; Pu, Shaofeng; Lv, Yingying; Chen, Yueping; Du, Dongping

    2017-01-01

    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. PMID:28223839

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

    SciTech Connect

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

    2013-08-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2011-11-01

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

  3. Hyaluronic acid gel injection to prevent thermal injury of adjacent gastrointestinal tract during percutaneous liver radiofrequency ablation.

    PubMed

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

    2013-08-01

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

  4. Surgical resection and radiofrequency ablation initiate cancer in cytokeratin-19+- liver cells deficient for p53 and Rb.

    PubMed

    Matondo, Ramadhan B; Toussaint, Mathilda Jm; Govaert, Klaas M; van Vuuren, Luciel D; Nantasanti, Sathidpak; Nijkamp, Maarten W; Pandit, Shusil K; Tooten, Peter Cj; Koster, Mirjam H; Holleman, Kaylee; Schot, Arend; Gu, Guoqiang; Spee, Bart; Roskams, Tania; Rinkes, Inne Borel; Schotanus, Baukje; Kranenburg, Onno; de Bruin, Alain

    2016-08-23

    The long term prognosis of liver cancer patients remains unsatisfactory because of cancer recurrence after surgical interventions, particularly in patients with viral infections. Since hepatitis B and C viral proteins lead to inactivation of the tumor suppressors p53 and Retinoblastoma (Rb), we hypothesize that surgery in the context of p53/Rb inactivation initiate de novo tumorigenesis.We, therefore, generated transgenic mice with hepatocyte and cholangiocyte/liver progenitor cell (LPC)-specific deletion of p53 and Rb, by interbreeding conditional p53/Rb knockout mice with either Albumin-cre or Cytokeratin-19-cre transgenic mice.We show that liver cancer develops at the necrotic injury site after surgical resection or radiofrequency ablation in p53/Rb deficient livers. Cancer initiation occurs as a result of specific migration, expansion and transformation of cytokeratin-19+-liver (CK-19+) cells. At the injury site migrating CK-19+ cells formed small bile ducts and adjacent cells strongly expressed the transforming growth factor β (TGFβ). Isolated cytokeratin-19+ cells deficient for p53/Rb were resistant against hypoxia and TGFβ-mediated growth inhibition. CK-19+ specific deletion of p53/Rb verified that carcinomas at the injury site originates from cholangiocytes or liver progenitor cells.These findings suggest that human liver patients with hepatitis B and C viral infection or with mutations for p53 and Rb are at high risk to develop tumors at the surgical intervention site.

  5. Radiofrequency Ablation versus Liver Resection for Colorectal Cancer Liver Metastasis: An Updated Systematic Review and Meta-analysis

    PubMed Central

    Han, Yue; Yan, Dong; Xu, Fei; Li, Xiao; Cai, Jian-Qiang

    2016-01-01

    Background: Controversial results about the therapeutic value of radiofrequency ablation (RFA) and liver resection (LR) in the treatment of colorectal cancer liver metastasis (CRCLM) have been reported. Thus, we performed the present meta-analysis to summarize the related clinical evidences. Methods: A systematic literature search was conducted using PubMed (Medline), EMBASE, Cochrane Library, and Web of Science, for all years up to April 2016. Pooled analyses of the overall survival (OS), progression-free survival (PFS), and morbidity rates were performed. Results: A total of 14 studies were finally enrolled in the meta-analysis. Patients treated by LR gained a longer OS and PFS than those of patients treated by RFA. Patients in the RFA group had lower morbidity rates than those of patients in the LR group. Publication bias analysis revealed that there was no significant publication bias in the meta-analysis. Conclusions: Patients with CRCLM gained much more survival benefits from LR than that from RFA. RFA rendered lower rates of morbidities. More well-designed randomized controlled trails comparing the therapeutic value of LR and RFA are warranted. PMID:27958231

  6. Surgical resection and radiofrequency ablation initiate cancer in cytokeratin-19+- liver cells deficient for p53 and Rb

    PubMed Central

    Govaert, Klaas M; van Vuuren, Luciel D; Nantasanti, Sathidpak; Nijkamp, Maarten W; Pandit, Shusil K; Tooten, Peter CJ; Koster, Mirjam H; Holleman, Kaylee; Schot, Arend; Gu, Guoqiang; Spee, Bart; Roskams, Tania; Rinkes, Inne Borel; Schotanus, Baukje; Kranenburg, Onno; de Bruin, Alain

    2016-01-01

    The long term prognosis of liver cancer patients remains unsatisfactory because of cancer recurrence after surgical interventions, particularly in patients with viral infections. Since hepatitis B and C viral proteins lead to inactivation of the tumor suppressors p53 and Retinoblastoma (Rb), we hypothesize that surgery in the context of p53/Rb inactivation initiate de novo tumorigenesis. We, therefore, generated transgenic mice with hepatocyte and cholangiocyte/liver progenitor cell (LPC)-specific deletion of p53 and Rb, by interbreeding conditional p53/Rb knockout mice with either Albumin-cre or Cytokeratin-19-cre transgenic mice. We show that liver cancer develops at the necrotic injury site after surgical resection or radiofrequency ablation in p53/Rb deficient livers. Cancer initiation occurs as a result of specific migration, expansion and transformation of cytokeratin-19+-liver (CK-19+) cells. At the injury site migrating CK-19+ cells formed small bile ducts and adjacent cells strongly expressed the transforming growth factor β (TGFβ). Isolated cytokeratin-19+ cells deficient for p53/Rb were resistant against hypoxia and TGFβ-mediated growth inhibition. CK-19+ specific deletion of p53/Rb verified that carcinomas at the injury site originates from cholangiocytes or liver progenitor cells. These findings suggest that human liver patients with hepatitis B and C viral infection or with mutations for p53 and Rb are at high risk to develop tumors at the surgical intervention site. PMID:27323406

  7. Bone radiofrequency ablation combined with prophylactic internal fixation for metastatic bone tumor of the femur from hepatocellular carcinoma.

    PubMed

    Ogura, Koichi; Miyake, Ryoko; Shiina, Shuichiro; Shinoda, Yusuke; Okuma, Tomotake; Kobayashi, Hiroshi; Goto, Takahiro; Nakamura, Kozo; Kawano, Hirotaka

    2012-08-01

    A 64-year-old man with 6-year history of hepatocellular carcinoma (HCC) was referred to us regarding bone metastasis to the right proximal femur. Although he underwent radiotherapy for pain palliation and local tumor control, the pain persisted and the tumor relapsed 3 months after the radiotherapy and he was thought to be at high risk of pathologic fracture. Given hypervascularity and large tumor size, a prophylactic internal fixation combined with adjuvant radiofrequency ablation (RFA) was proposed to reduce blood loss and prevent viable tumor cells being disseminated. His postoperative course was uneventful without requiring blood transfusion and preoperative symptoms immediately disappeared after surgery. He became capable of weight-bearing walk with a single cane and was almost asymptomatic without local progression on the plain radiographs when he died 14 months after surgery. Combination therapy of RFA and internal fixation using intramedullary nailing for metastases of the long bones from HCC seems to be a very promising technique both for sufficient pain relief and for local control of the tumor. Adjuvant RFA may become a potential option for patients with metastases of the long bones for the purpose of prevention of tumor dissemination and reduction of intraoperative blood loss.

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

    PubMed Central

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

    2016-01-01

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

  9. Clinical course of arrhythmogenic right ventricular cardiomyopathy in the era of implantable cardioverter-defibrillators and radiofrequency catheter ablation.

    PubMed

    Komura, Masatoshi; Suzuki, Jun-Ichi; Adachi, Susumu; Takahashi, Atsushi; Otomo, Kenichiro; Nitta, Junichi; Nishizaki, Mitsuhiro; Obayashi, Tohru; Nogami, Akihiko; Satoh, Yasuhiro; Okishige, Kaoru; Hachiya, Hitoshi; Hirao, Kenzo; Isobe, Mitsuaki

    2010-01-01

    This study investigated the clinical course of arrhythmogenic right ventricular cardiomyopathy (ARVC) patients and in particular evaluated the contribution of radiofrequency catheter ablation (RFCA) and an implantable cardioverter-defibrillator (ICD) to the treatment of ARVC. ARVC is a myocardial disorder and a cause of sudden cardiac death due to ventricular tachycardia (VT). Little is known about its prognosis in Japanese ARVC patients. Thirty-five ARVC patients were studied. Mean age of patients whose onset of ARVC was congestive heart failure (CHF) (66.0 +/- 4.0 years) was significantly higher than those whose onset was VT (44.5 +/- 14.8 years, P < 0.05). ARVC patients with CHF onset showed significantly higher death rates compared to those with VT onset. ICD treatment significantly reduced episodes of hospitalization due to VT (0.1 +/- 0.4 episodes) in comparison to treatment by RFCA (1.7 +/- 2.2 episodes, P < 0.03). RFCA treatment did not reduce recurrence of VT in the follow-up period. ICD therapy showed comparable mortality to RFCA treatment. The prognosis of ARVC with CHF onset is poor. ICD therapy significantly reduced hospitalization due to VT compared with RFCA treatment. ICD implantation in combination with medication may be a better treatment for ARVC.

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

    PubMed Central

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

    2016-01-01

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

  11. Impact of Systemic Therapy and Recurrence Pattern on Survival Outcome after Radiofrequency Ablation for Colorectal Liver Metastases

    PubMed Central

    Stang, Axel; Donati, Marcello; Weilert, Hauke; Oldhafer, Karl Jürgen

    2016-01-01

    Background: Most patients undergoing radiofrequency ablation (RFA) of colorectal liver metastasases (CLM) develop disease recurrence, but little is known about the effect of recurrence patterns and/or systemic therapy on outcome. In this study, we examined the recurrence patterns and survival after systemic therapy plus RFA in patients with unresectable CLM without extrahepatic disease. The aims were to analyze the effect of recurrence patterns on survival and to assess the relative benefit contributed by systemic therapy and local ablation to disease control and patient outcome. Methods: From January 2002 to December 2012, 113 patients underwent RFA of liver-limited CLM after systemic therapy. Univariate and multivariate analyses for associations between clinical and/or treatment-related variables, recurrence-free survival (RFS), recurrence patterns, and overall survival (OS) were carried out. Results: Of 113 patients, 105 (92.8%) had disease recurrence (median RFS: 6.1 months). Lower post-recurrence OS was observed after early (≤6 months) than after late recurrence (8.5 versus 24.0 months, p < 0.001). Recurrence sites were RFA-sites only (4.8%), liver-only (57.1%), lung-only (10.5%), or multiple (27.6%); the corresponding post-recurrence OS was 21, 19, 39, and 7 months (p < 0.001), respectively. Response to pre-RFA systemic therapy was the strongest predictor for OS (hazard ratio [HR] 5.28), RFS (HR 3.30), early (odds ratio [OR] 6.34) and multiple-site recurrence (OR 3.83) (p < 0.01), respectively; only responders achieved 5-year OS and RFS (29% and 12% versus 0% and 0% for non-responders, p < 0.001, respectively). Conclusions: Survival after RFA for liver-limited CLM is strongly linked to the timing and pattern of non-local disease recurrence. Local ablation efficacy is necessary but not sufficient to obtain long-term disease control. Effective pre-RFA systemic therapy does favourably affect the incidence, timing and patterns of recurrence and long

  12. Monitoring radio-frequency thermal ablation with ultrasound by low frequency acoustic emissions--in vitro and in vivo study.

    PubMed

    Winkler, Itai; Adam, Dan

    2011-05-01

    The object of this study was to evaluate the monitoring of thermal ablation therapy by measuring the nonlinear response to ultrasound insonation at the region being treated. Previous reports have shown that during tissue heating, microbubbles are formed. Under the application of ultrasound, these microbubbles may be driven into nonlinear motion that produces acoustic emissions at sub-harmonic frequencies and a general increase of emissions at low frequencies. These low frequency emissions may be used to monitor ablation surgery. In this study, a modified commercial ultrasound system was used for transmitting ultrasound pulses and for recording raw RF-lines from a scan plane in porcine (in vitro) and rabbit (in vivo) livers during radio-frequency ablation (RFA). The transmission pulse was 15 cycles in length at 4 MHz (in vitro) and 3.6 MHz (in vivo). Thermocouples were used for monitoring temperatures during the RFA treatment.In the in vitro experiments, recorded RF signals (A-lines) were segmented, and the total energy was measured at two different frequency bands: at a low frequency band (LFB) of 1-2.5 MHz and at the transmission frequency band (TFB) of 3.5-4.5 MHz. The mean energy at the LFB and at the TFB increased substantially in areas adjacent to the RF needle. These energies also changed abruptly at higher temperatures, thus, producing great variance in the received energy. Mean energies in areas distant from RF needle showed little change and variation during treatment. It was also shown that a 3 dB increase of energy at the low frequency band was typically obtained in regions in which temperature was above 53.3 ± 5° C. Thus, this may help in evaluating regions undergoing hyperthermia. In the in vivo experiments, an imaging algorithm based on measuring the LFB energy was used. The algorithm performs a moving average of the LFB energies measured at segments within the scan plane.Results show that a colored region is formed on the image and that it is

  13. Successful Non-fluoroscopic Radiofrequency Ablation of Incessant Atrial Tachycardia in a High Risk Twin Pregnancy.

    PubMed

    Zuberi, Zia; Silberbauer, John; Murgatroyd, Francis

    2014-01-01

    We describe a patient presenting with incessant ectopic atrial tachycardia during a high risk twin pregnancy. Tachycardia was resistant to escalating doses of beta-blockade with digoxin. Because of increasing left ventricular dysfunction early in the third trimester, catheter ablation was performed successfully at 30 weeks gestation. Electro-anatomic mapping permitted the entire procedure to be conducted without the use of ionizing radiation. The pregnancy proceeded to successful delivery near term and after three years the patient remains recurrence free with normal left ventricular function, off all medication.

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

    PubMed

    Saidatul, A; Azlan, Ca; Megat Amin, Msa; Abdullah, Bjj; Ng, Kh

    2010-01-01

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

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

    SciTech Connect

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

    2010-04-15

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

  16. Radiofrequency ablation of liver metastases-software-assisted evaluation of the ablation zone in MDCT: tumor-free follow-up versus local recurrent disease.

    PubMed

    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 < 0.05). Furthermore, ln ratios corresponding to volume, RECIST, and WHO differed significantly between the two groups. Attenuation evaluations showed no significant differences, but there was a trend toward attenuation assessment for the parameter lnQ28/0(attenuation) (p = 0.0527), showing higher values for group 1 (-0.4 + or - 0.3) compared to group 2 (-0.2 + or - 0.2). In conclusion, hepatic metastases and their zone of coagulation necrosis after RFA differed significantly between tumor

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

    PubMed

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

    2009-04-01

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

  18. Percutaneous intraductal radiofrequency ablation for treatment of biliary stent occlusion: A preliminary result

    PubMed Central

    Xia, Ning; Gong, Ju; Lu, Jian; Chen, Zhi-Jin; Zhang, Li-Yun; Wang, Zhong-Min

    2017-01-01

    AIM To assess the feasibility and effectiveness of a novel application of percutaneous intraductal radiofrequency (RF) for the treatment of biliary stent obstruction. METHODS We specifically report a retrospective study presenting the results of percutaneous intraductal RF in patients with biliary stent occlusion. A total of 43 cases involving biliary stent obstruction were treated by placing an EndoHPB catheter and percutaneous intraductal RF was performed to clean stents. The stent patency was evaluated by cholangiography and follow-up by contrast enhanced computed tomography or ultrasound after the removal of the drainage catheter. RESULTS Following the procedures, of the 43 patients, 40 survived and 3 died with a median survival of 80.5 (range: 30-243) d. One patient was lost to follow-up. One patient had the stent patent at the time of last follow-up. Two patients with stent blockage at 35 d and 44 d after procedure underwent percutaneous transhepatic drain insertion only. The levels of bilirubin before and after the procedure were 128 ± 65 μmol/L and 63 ± 29 μmol/L, respectively. There were no related complications (haemorrhage, bile duct perforation, bile leak or pancreatitis) and all patients’ stent patency was confirmed by cholangiography after the procedure, with a median patency time of 107 (range: 12-180) d. CONCLUSION This preliminary clinical study demonstrated that percutaneous intraductal RF is safe and effective for the treatment of biliary stent obstruction, increasing the duration of stent patency, although randomized controlled trials are needed to confirm the effectiveness of this approach. PMID:28348491

  19. Infusion of hypertonic saline into the lung parenchyma during radiofrequency ablation of the lungs with multitined expandable electrodes: results using a porcine model.

    PubMed

    Iishi, Tatsuhiko; Hiraki, Takao; Mimura, Hidefumi; Gobara, Hideo; Kurose, Taichi; Fujiwara, Hiroyasu; Sakurai, Jun; Yanai, Hiroyuki; Yoshino, Tadashi; Kanazawa, Susumu

    2009-06-01

    The present study was performed to clarify the effect of hypertonic saline infusion into the lung parenchyma on radiofrequency ablation (RFA) of the lungs. A total of 20 ablation zones were created in 3 pigs. The ablation zones were divided into 3 groups. Group 1 (n=6) consisted of ablation zones created by applying smaller radiofrequency (RF) power without saline infusion; group 2 (n=5) zones were created by applying greater RF power without saline infusion;and group 3 (n=9) zones were created by applying greater RF power with saline infusion. The techniques of saline infusion included administration of hypertonic saline 1 ml before RFA, followed by continuous administration at a rate of 1 ml/min during the first 2 min after the initiation of RFA. The ablation parameters and coagulation necrosis volumes were compared among the groups. Group 3 had a tendency toward smaller mean impedance than group 1 (p=0.059) and group 2 (p=0.053). Group 3 showed significantly longer RF application time than group 2 (p=0.004) and significantly greater maximum RF power than group 1 (p=0.001) and group 2 (p=0.004). Group 3 showed significantly larger coagulation necrosis volume (mean, 1,421mm3) than group 2 (mean, 858 mm3, p=0.039) and had a tendency toward larger necrosis volume than group 1 (mean, 878 mm3, p=0.077). Although this small study had limited statistical power, hypertonic saline infusion during RFA appeared to enlarge coagulation necrosis of the lung parenchyma.

  20. Radiofrequency ablation of unresectable colorectal liver metastases: trends in management and outcome during a decade at a single center

    PubMed Central

    Schulz, Anselm; Drolsum, Anders; Guren, Marianne Grønlie; Kløw, Nils Einar; Bjørnbeth, Bjørn Atle

    2015-01-01

    Background Radiofrequency ablation (RFA) is widely used for treatment of colorectal liver metastases (CRLM). Purpose To evaluate the effect of increased experience in RFA of CRLM on morbidity and survival, and the trends in patient management and outcomes during the last decade. Material and Methods Hospital records of the initial 52 consecutive patients who underwent RFA (56 procedures/70 lesions) were retrospectively reviewed. The patients were divided into two groups according to time period of treatment, period I (2001–2006: n = 26) and period II (2007–2011: n = 26). Results Concomitant liver resection was performed in 15 patients in each period. Operative morbidity decreased from 47% to 19% (P = 0.047). Most complications were found in patients who underwent a concomitant liver resection and not related to the ablation per se. Local recurrence rate decreased from 19.4% to 12.9% (P = 0.526). At least one risk factor for recurrence was found in patients with local recurrence (n = 11): subcapsular localization (n = 4), tumor size >3 cm and subcapsular localization (n = 2), and perivascular localization (portal veins/hepatic veins) (n = 5). Median overall survival was 32 months in period I and 49 months in period II, whereas estimated 5-year survival was 19% and 36%, respectively (P = 0.09). Adjuvant chemotherapy was given to four patients (15.4%) in period I and 13 patients (50%) in period II (P = 0.017). Conclusion RFA alone or in combination with liver resection is a potentially curative treatment to selected patients with CRLM. Over time, the morbidity and survival have improved in RFA of CRLM. Although a possible effect of a learning curve should be taken into consideration in the appraisal of this improvement, it is more likely to be attributable to optimization of indication, development in surgical techniques, and increased use of perioperative chemotherapy. PMID:26346740

  1. [Examination of percutaneous microwave coagulation and radiofrequency ablation therapy for metastatic liver cancer].

    PubMed

    Ohkawa, Shinichi; Hirokawa, Satoru; Masaki, Takahiro; Miyakawa, Kaoru; Tarao, Kazuo; Akaike, Makoto; Sugimasa, Yukio; Takemiya, Shoji; Sairenji, Motonori; Motohashi, Hisahiko

    2002-11-01

    Percutaneous microwave coagulation therapy (PMCT) and radio frequency ablation therapy (RFA) as treatments for metastatic liver cancer were examined. PMCT or RFA was administered for 18 metastatic liver cancer lesions (primary lesion: 11 colon rectal cancer, one esophagus cancer, one thyroid cancer, one pancreatic cancer, one pheochromocytoma) in 16 patients from July 1999 to March 2002. RFA was performed 1 time for 12 minutes in principle, using a Cool-tip RF system from Radionics. Patients had a mean age of 58.8 years and the mean diameter of the neoplasms was about 22 mm. Critical complications were not seen. The rate of partial recurrence was 35.3% as of March, 2002, in an average observation period of 7.3 months. On the other hand, with the medical treatment for the hepatocellular carcinoma provided during this period, the rate of partial recurrence was 14.8%. The treatment of metastatic liver cancer by PMCT and RFA is associated with a high rate of a recurrence as compared with hepatocellular carcinoma, and needs to be examined to discover ways of adaptation and improvement of the technology.

  2. Treatment of osteolytic solitary painful osseous metastases with radiofrequency ablation or cryoablation: A retrospective study by propensity analysis

    PubMed Central

    ZUGARO, LUIGI; DI STASO, MARIO; GRAVINA, GIOVANNI LUCA; BONFILI, PIERLUIGI; GREGORI, LORENZO; FRANZESE, PIETRO; MARAMPON, FRANCESCO; TOMBOLINI, VINCENZO; DI CESARE, ERNESTO; MASCIOCCHI, CARLO

    2016-01-01

    The present study aimed to measure the improvement in pain relief and quality of life in patients with osteolytic solitary painful bone metastasis treated by cryoablation (CA) or radiofrequency ablation (RFA). Fifty patients with solitary osteolytic painful bone metastases were retrospectively studied and selected by propensity analysis. Twenty-five patients underwent CA and the remaining twenty-five underwent RFA. Pain relief, in terms of complete response (CR), the number of patients requiring analgesia and the changes in self-rated quality of life (QoL) were measured following the two treatments. Thirty-two percent of patients treated by CA experienced a CR at 12 weeks versus 20% of patients treated by RFA. The rate of CR increased significantly with respect to baseline only in the group treated by CA. In both groups there was a significant change in the partial response with respect to baseline (36% in the CA group vs. 44% in the RFA group). The recurrence rate in the CA and RFA groups was 12% and 8%, respectively. The reduction in narcotic medication requirements with respect to baseline was only significant in the group treated by CA. A significant improvement in self-rated QoL was observed in both groups. The present study seems to suggest that CA only significantly improves the rate of CR and decreases the requirement of narcotic medications. Both CA and RFA led to an improvement in the self-rated QoL of patients after the treatments. However, the results of the present study should be considered as preliminary and to serve as a framework around which future trials may be designed. PMID:26998106

  3. Laparoscopic resection vs laparoscopic radiofrequency ablation for the treatment of small hepatocellular carcinomas: A single-center analysis

    PubMed Central

    Casaccia, Marco; Santori, Gregorio; Bottino, Giuliano; Diviacco, Pietro; Andorno, Enzo

    2017-01-01

    AIM To compare survival and recurrence after laparoscopic liver resection (LLR) and laparoscopic radiofrequency ablation (LRFA) for the treatment of small hepatocellular carcinoma (HCC). METHODS Between June 1, 2005 and November 30, 2010, 46 patients (62.26 ± 8.55 years old; female/male: 12/34) treated for small HCC were enrolled following strict criteria. Patients with better liver function and larger tumors were referred for LLR (n = 24), while those with poorer liver function and multiple tumors were referred for LRFA (n = 22), and they were then followed for similar durations (44.74 ± 21.3 mo for LLR vs 40.27 ± 30.8 mo for LRFA). RESULTS The LLR and LRFA groups were homogeneous with regard to age, sex, etiology of liver cirrhosis, and AFP levels. The overall survival (OS) and disease-free survival (DFS) probability was 0.354 and 0.260, respectively. A significantly higher OS was observed in the LLR group (LLR: 0.442; LRFA: 0.261; P = 0.048), whereas no statistical difference was found for DFS (LLR: 0.206; LRFA: 0.286; P = 0.205). In the LRFA group was treated a greater number of nodules (LLR: 1.41 ± 0.77; LRFA: 2.72 ± 1.54; P < 0.001). Cox regression analysis found the number of intraoperative HCC nodules as the unique variable statistically significant for OS (hazard ratio: 2.225; P < 0.001). The rank-hazard plot showed a steeper increase of relative hazard for intraoperative nodules > 2. CONCLUSION Our preliminary results confirm the superiority of hepatic resection on thermoablation in the treatment of small HCC in selected patients, when both approaches are made laparoscopically. LLR showed better results compared to LRFA in terms of OS. These data need to be confirmed by further studies on a larger number of patients. PMID:28216972

  4. Radiofrequency ablation of hepatocellular carcinomas: A new spectrum of anesthetic experience at a tertiary care hospital in Pakistan

    PubMed Central

    Shamim, Faisal; Asghar, Ali; Tauheed, Saman; Yahya, Muhammad

    2017-01-01

    Background: Radiofrequency ablation (RFA) is a minimally invasive technique of tumor destruction for patients with hepatic cancer who are not candidates for conventional therapy. The therapy required general anesthesia (GA) or sedation to ensure patient safety and comfort. The study is aimed to report and evaluate factors that influenced the periprocedural anesthetic management, drugs used, and complications during and immediately after RFA procedure for hepatocellular carcinoma. Methods: For this retrospective study, we included 46 patients who underwent percutaneous RFA under GA or conscious sedation from January 2010 to June 2013 in Aga Khan University Hospital, Pakistan. The patients' characteristics, hepatic illness severity (Child-Pugh classification), anesthetic techniques, drugs, and complications of procedure were collected on a predesigned approved form. The data were assessed and summarized using descriptive statistics. Results: The majority of patients were female (57%) and mostly classified as American Society of Anesthesiologist III (65.2%). The preoperative hepatic illness severity in most patients was Child-Pugh Class A (76.10%). Thirty-eight patients (69.09%) had only single lesion and majority number of lesions were <3 cm (65.45). GA was the main anesthetic technique (87%) with laryngeal mask airway as an airway adjunct predominantly (70%). The mainly used anesthetic agents for hypnosis and analgesia were propofol and fentanyl, respectively. Pain was the only significant complaint in postoperative period but only in nine (19%) patients and mild in nature. Conclusions: Percutaneous RFA is a safe treatment of hepatocellular cancer. The procedure required good anesthetic support in the form of sedation-analgesia or complete GA that ensures maximum patient comfort and technical success of the procedure. PMID:28217048

  5. Prediction of very late arrhythmia recurrence after radiofrequency catheter ablation of atrial fibrillation: The MB-LATER clinical score.

    PubMed

    Mujović, Nebojša; Marinković, Milan; Marković, Nebojša; Shantsila, Alena; Lip, Gregory Y H; Potpara, Tatjana S

    2017-01-20

    Reliable prediction of very late recurrence of atrial fibrillation (VLRAF) occuring >12 months after catheter ablation (CA) in apparently "cured" patients could optimize long-term follow-up and modify decision-making regarding the discontinuation of oral anticoagulant therapy. In a single-centre cohort of consecutive patients post radiofrequency AFCA, we retrospectively derived a novel score for VLRAF prediction. Of 133 consecutive post AFCA patients (mean age 56.9 ± 11.8 years, 63.9% male, 69.2% with paroxysmal AF) who were arrhythmia-free at 12 months (excluding 3-month "blanking period"), 20 patients expirienced a VLRAF during a 29.1 ± 10.1-month follow-up, with a 3-year cumulative VLRAF rate of 31.1%. The MB-LATER score (Male, Bundle brunch block, Left atrium ≥47 mm, Type of AF [paroxysmal, persistent or long-standing persistent], and ER-AF = early recurrent AF), had better predictive ability for VLRAF (AUC 0.782) than the APPLE, ALARMc, BASE-AF2, CHADS2, CHA2DS2VASc or HATCH score (AUC 0.716, 0.671, 0.648, 0.552, 0.519 and 0.583, respectively), resulted in an improved net reclassification index (NRI) of 48.6-95.1% and better identified patients with subsequent VLRAF using decision-curve analysis (DCA). The MB-LATER score provides a readily available VLRAF risk assessment, and performs better than other scores. Validation of the MB-LATER score in other cohorts is underway.

  6. Prediction of very late arrhythmia recurrence after radiofrequency catheter ablation of atrial fibrillation: The MB-LATER clinical score

    PubMed Central

    Mujović, Nebojša; Marinković, Milan; Marković, Nebojša; Shantsila, Alena; Lip, Gregory Y. H.; Potpara, Tatjana S.

    2017-01-01

    Reliable prediction of very late recurrence of atrial fibrillation (VLRAF) occuring >12 months after catheter ablation (CA) in apparently “cured” patients could optimize long-term follow-up and modify decision-making regarding the discontinuation of oral anticoagulant therapy. In a single-centre cohort of consecutive patients post radiofrequency AFCA, we retrospectively derived a novel score for VLRAF prediction. Of 133 consecutive post AFCA patients (mean age 56.9 ± 11.8 years, 63.9% male, 69.2% with paroxysmal AF) who were arrhythmia-free at 12 months (excluding 3-month “blanking period”), 20 patients expirienced a VLRAF during a 29.1 ± 10.1-month follow-up, with a 3-year cumulative VLRAF rate of 31.1%. The MB-LATER score (Male, Bundle brunch block, Left atrium ≥47 mm, Type of AF [paroxysmal, persistent or long-standing persistent], and ER-AF = early recurrent AF), had better predictive ability for VLRAF (AUC 0.782) than the APPLE, ALARMc, BASE-AF2, CHADS2, CHA2DS2VASc or HATCH score (AUC 0.716, 0.671, 0.648, 0.552, 0.519 and 0.583, respectively), resulted in an improved net reclassification index (NRI) of 48.6–95.1% and better identified patients with subsequent VLRAF using decision-curve analysis (DCA). The MB-LATER score provides a readily available VLRAF risk assessment, and performs better than other scores. Validation of the MB-LATER score in other cohorts is underway. PMID:28106147

  7. Comparison of percutaneous radiofrequency ablation and CyberKnife® for initial solitary hepatocellular carcinoma: A pilot study

    PubMed Central

    Shiozawa, Kazue; Watanabe, Manabu; Ikehara, Takashi; Matsukiyo, Yasushi; Kogame, Michio; Kishimoto, Yui; Okubo, Yusuke; Makino, Hiroyuki; Tsukamoto, Nobuhiro; Igarashi, Yoshinori; Sumino, Yasukiyo

    2015-01-01

    AIM: To compare therapeutic outcomes and adverse events in initial solitary hepatocellular carcinoma (HCC) treated with radiofrequency ablation (RFA) and CyberKnife®. METHODS: Seventy three consecutive patients with initial solitary HCC treated with RFA (38 patients; RFA group) and CyberKnife® (35 patients; CK group) were enrolled in this study. Background factors were compared between the two groups. Local and intrahepatic distant recurrence control, and cumulative survival rates were compared between the two groups. These were determined using the Kaplan-Meier method, and the significance of differences was analyzed by log-rank test. The presence of more grade 3 on CTCAE ver. 4.0 early and late adverse events was investigated. RESULTS: In background factors, age was significantly higher (P = 0.005) and the tumor diameter was significantly larger (P = 0.001) in the CK group. The 1-year local recurrence control rates were 97.4% and 97.1% in the RFA and CK groups, respectively (P = 0.71); the 1-year intrahepatic distant recurrence control rates were 85.6% and 86.1%, respectively (P = 0.91); and the 1-year cumulative survival rates were 100% and 95.2%, respectively (P = 0.075), showing no significant difference in any rate between the two groups. There were no late adverse event in the RFA group, but 11.4% in the CK group had late adverse events. In the CK group, the Child-Pugh score at 12 mo after treatment was significantly higher than that in the RFA group (P = 0.003) and significantly higher than the score before treatment (P = 0.034). CONCLUSION: The occurrence of adverse events is a concern, but CyberKnife® treatment is likely to become an important option for local treatment of early HCC. PMID:26730160

  8. Clinical significance and predictive factors of early massive recurrence after radiofrequency ablation in patients with a single small hepatocellular carcinoma

    PubMed Central

    Cho, Ju-Yeon; Choi, Moon Seok; Lee, Gil Sun; Sohn, Won; Ahn, Jemma; Sinn, Dong-Hyun; Gwak, Geum-Youn; Paik, Yong-Han; Lee, Joon Hyeok; Koh, Kwang Cheol; Paik, Seung Woon

    2016-01-01

    Background/Aims Radiofrequency ablation (RFA) is one of the most frequently applied curative treatments in patients with a single small hepatocellular carcinoma (HCC). However, the clinical significance of and risk factors for early massive recurrence after RFA—a dreadful event limiting further curative treatment—have not been fully evaluated. Methods In total, 438 patients with a single HCC of size ≤3 cm who underwent percutaneous RFA as an initial treatment between 2006 and 2009 were included. Baseline patient characteristics, overall survival, predictive factors, and recurrence after RFA were evaluated. In addition, the incidence, impact on survival, and predictive factors of early massive recurrence, and initial recurrence beyond the Milan criteria within 2 years were also investigated. Results During the median follow-up of 68.4 months, recurrent HCC was confirmed in 302 (68.9%) patients, with early massive recurrence in 27 patients (6.2%). The 1-, 3-, and 5-year overall survival rates were 95.4%, 84.7%, and 81.8%, respectively, in patients with no recurrence, 99.6%, 86.4%, and 70.1% in patients with recurrence within the Milan criteria or late recurrence, and 92.6%, 46.5%, and 0.05% in patients with early massive recurrence. Multivariable analysis identified older age, Child-Pugh score B or C, and early massive recurrence as predictive of poor overall survival. A tumor size of ≥2 cm and tumor location adjacent to the colon were independent risk factors predictive of early massive recurrence. Conclusion Early massive recurrence is independently predictive of poor overall survival after RFA in patients with a single small HCC. Tumors sized ≥2 cm and located adjacent to the colon appear to be independent risk factors for early massive recurrence. PMID:28081587

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

    SciTech Connect

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

    2007-07-15

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

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

    PubMed Central

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

    2015-01-01

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

  11. Effectiveness of combined (131)I-chTNT and radiofrequency ablation therapy in treating advanced hepatocellular carcinoma.

    PubMed

    Tu, Jianfei; Ji, Jiansong; Wu, Fazong; Wang, Yonghui; Zhang, Dengke; Zhao, Zhongwei; Ying, Xihui

    2015-03-01

    To investigate the effectiveness of monoclonal antibody ((131)I-chTNT) and radiofrequency ablation (RFA) combination therapy in treating middle-advanced stage hepatocellular carcinoma (HCC). Thirty-four patients diagnosed with HCC patients, divided into two groups comprised of 22 and 12 cases were included in this retrospective study. The two groups received RFA with or without ((131)I-chTNT) therapy, respectively. The patients in these groups were followed up for a median of 31 and 35 months, respectively. Patient survival was evaluated using Kaplan-Meier method and safety profiles were determined by analyzing liver, thyroid, and bone marrow toxicities. This retrospective study showed that survival time of the patients who received combination therapy was significantly longer than that of the RFA group (P = 0.052). The median progress-free survival of patients in the two groups was 23 and 7 months, respectively, and the difference was significant (P = 0.04). Tumor recurred in 3.5-8.7 months in four of the combination group patients, among which three had newly developed lesions. The red blood cells and platelets counts were not altered on day 7 and 1 month of the treatment, however, number of white blood cells was significantly increased on day 7 which was reversed back to the normal range in 2 weeks. The ALT and AST were also not significantly altered on day 7 and 1 month of therapy. In middle-advanced stage HCC patients, the combination of (131)I-chTNT and RFA therapy was found to be significantly more effective than the RFA treatment alone as assessed in short-term follow-up. However, the dose we used was insufficient to completely block the local recurrence of the lesions with a diameter of 5 cm or larger.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  14. Impact of Radiofrequency Ablation-Induced Glisson’s Capsule-Associated Complications in Patients with Hepatocellular Carcinoma

    PubMed Central

    Chiba, Tetsuhiro; Yokoyama, Masayuki; Inoue, Masanori; Kanogawa, Naoya; Saito, Tomoko; Suzuki, Eiichiro; Ooka, Yoshihiko; Tawada, Akinobu; Yokosuka, Osamu

    2017-01-01

    Background Radiofrequency ablation (RFA) is commonly used to locally treat hepatocellular carcinoma (HCC). However, when tumors are close to the Glisson’s capsule, RFA may induce injury in this region, complicating therapeutic efforts. We investigated the impact of RFA-induced Glisson’s capsule-associated complications on liver function and prognosis of HCC patients. Methods We retrospectively reviewed our patient database and found 170 early-stage HCC patients treated via RFA from April 2004 to December 2012. We defined RFA-induced Glisson’s capsule-associated complication as lasting hepatic arterioportal (AP) fistula, major intrahepatic bile-duct dilatation (affecting two or more subsegments), or hepatic infarction. We also defined liver failure as initial occurrence of either total bilirubin increase (>3.0 mg/dL), uncontrolled ascites, or encephalopathy. Results In our cohort, 15 patients had RFA-induced Glisson’s capsule-associated complications (incidence of related complications, with some overlap: lasting AP fistula, n = 9; major intrahepatic bile-duct dilatation, n = 7; and hepatic infarction, n = 2). The cumulative incidence of liver failure before stage progression was significantly higher and the median overall survival (OS) was significantly lower (52.3 months) in HCC patients with Glisson’s capsule-associated complications than in those without Glisson’s capsule-associated complications (95.0 months). In addition, multivariate analysis demonstrated that Glisson’s capsule-associated complication was a significant independent factor associated with OS. Conclusions In this study, we have shown that early-stage HCC patients with RFA-induced Glisson’s capsule-associated complications may have higher risks in poor prognosis. PMID:28099460

  15. Catheter ablation.

    PubMed

    Fromer, M; Shenasa, M

    1991-02-01

    Catheter ablation is gaining increasing interest for the therapy of symptomatic, sustained arrhythmias of various origins. The scope of this review is to give an overview of the biophysical aspects and major characteristics of some of the most widely used energy sources in catheter ablation, e.g., the discharge of conventional defibrillators, modified defibrillators, laser light, and radiofrequency current application. Results from animal studies are considered to explain the basic mechanisms of catheter ablation. The recent achievements with the use of radiofrequency current to modify or ablate cardiac conduction properties are outlined in more detail.

  16. Effects of preceding endoscopic mucosal resection on the efficacy and safety of radiofrequency ablation for treatment of Barrett’s esophagus: results from the United States Radiofrequency Ablation Registry

    PubMed Central

    Li, N.; Pasricha, S.; Bulsiewicz, W. J.; Pruitt, R. E.; Komanduri, S.; Wolfsen, H. C.; Chmielewski, G. W.; Corbett, F. S.; Chang, K. J.; Shaheen, N. J.

    2016-01-01

    Summary The effects of preceding endoscopic mucosal resection (EMR) on the efficacy and safety of radiofrequency ablation (RFA) for treatment of nodular Barrett’s esophagus (BE) is poorly understood. Prior studies have been limited to case series from individual tertiary care centers. We report the results of a large, multicenter registry. We assessed the effects of preceding EMR on the efficacy and safety of RFA for nodular BE with advanced neoplasia (high-grade dysplasia or intramucosal carcinoma) using the US RFA Registry, a nationwide study of BE patients treated with RFA at 148 institutions. Safety outcomes included stricture, gastrointestinal bleeding, and hospitalization. Efficacy outcomes included complete eradication of intestinal metaplasia (CEIM), complete eradication of dysplasia (CED), and number of RFA treatments needed to achieve CEIM. Analyses comparing patients with EMR before RFA to patients undergoing RFA alone were performed with Student’s t-test, Chi-square test, logistic regression, and Kaplan–Meier analysis. Four hundred six patients were treated with EMR before RFA for nodular BE, and 857 patients were treated with RFA only for non-nodular BE. The total complication rates were 8.4% in the EMR-before-RFA group and 7.2% in the RFA-only group (P = 0.48). Rates of stricture, bleeding, and hospitalization were not significantly different between patients treated with EMR before RFA and patients treated with RFA alone. CEIM was achieved in 84% of patients treated with EMR before RFA, and 84% of patients treated with RFA only (P = 0.96). CED was achieved in 94% and 92% of patients in EMR-before-RFA and RFA-only group, respectively (P = 0.17). Durability of eradication did not differ between the groups. EMR-before-RFA for nodular BE with advanced neoplasia is effective and safe. The preceding EMR neither diminished the efficacy nor increased complication rate of RFA treatment compared to patients with advanced neoplasia who had RFA with no

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

    PubMed

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

    2008-01-01

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

  18. Radiofrequency Ablation of Renal Tumors with an Expandable Multitined Electrode: Results, Complications, and Pilot Evaluation of Cooled Pyeloperfusion for Collecting System Protection

    SciTech Connect

    Rouviere, Olivier Badet, Lionel; Murat, Francois Joseph; Marechal, Jean Marie; Colombel, Marc; Martin, Xavier; Lyonnet, Denis; Gelet, Albert

    2008-05-15

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

  19. An observational feasibility study to assess the safety and effectiveness of intranasal fentanyl for radiofrequency ablations of the lumbar facet joints

    PubMed Central

    Bartoszek, Michael W; McCoart, Amy; Hong, Kyung-soo Jason; Haley, Chelsey; Highland, Krista Beth; Plunkett, Anthony R

    2017-01-01

    Purpose The purpose of the present observational, feasibility study is to assess the preliminary safety and effectiveness of intranasal fentanyl for lumbar facet radiofrequency ablation procedures. Patients and methods This cohort observational study included 23 adult patients. Systolic and diastolic blood pressures, heart rate, oxygen saturation percent, Pasero Opioid-Induced Sedation Scale score, and the Defense and Veterans Pain Rating Scale pain score were assessed prior to the procedure and intranasal fentanyl (100 μg) administration and every 15 minutes after administration, up to 60 minutes post administration. Follow-up of patient satisfaction with pain control and treatment was assessed 24 hours after discharge. The primary outcome was safety as evidenced by adverse events. Secondary outcomes included the above-mentioned vital signs and pain ratings. Results No adverse events occurred in the present study and all participants maintained an acceptable level of awareness throughout the assessment period. One-way repeated measures analyses of covariance tests with Bonferroni-adjusted means indicated that oxygen saturation, blood pressure, and heart rate changed from baseline, whereas pain scores were lower at post-administration levels compared with baseline. Finally, the majority of participants reported being satisfied with pain control and treatment. Conclusion Preliminary evidence indicates that intranasal fentanyl is safe and effective for lumbar facet radiofrequency ablation procedures. Future rigorous randomized control trials are needed to confirm the present results and to examine the effects of intranasal fentanyl on intraoperative and postoperative opioid use. PMID:28243139

  20. Endoscopic Radiofrequency Ablation of the Sacroiliac Joint Complex in the Treatment of Chronic Low Back Pain: A Preliminary Study of Feasibility and Efficacy of a Novel Technique.

    PubMed

    Choi, Won-Suh; Kim, Jin-Sung; Ryu, Kyeong-Sik; Hur, Jung-Woo; Seong, Ji-Hoon; Cho, Hyun-Jin

    2016-01-01

    Background. Radiofrequency ablation (RFA) is a less invasive technique for treatment of sacroiliac joint (SIJ) pain. Objective. To evaluate the feasibility and efficacy of endoscope-guided RFA for the treatment of CLBP from the SIJ complex. Methods. In this retrospective study, the medical records of 17 patients who underwent endoscope-guided RFA of the SIJ complex were reviewed. A bipolar radiofrequency probe was used to lesion the posterior capsule of the SIJ as well as the lateral branches of S1, S2, S3, and the L5 dorsal ramus in multiple locations. We visualized the ablation area using endoscope. We assessed visual analogue scale (VAS) and the Oswestry disability index (ODI) preoperatively, immediately postop, and at 1-, 3-, and 6-month postop outpatient clinic visits. Patient satisfaction of the procedure was assessed in percentages. Results. The mean duration of operation was 20 to 50 minutes. The mean VAS and the ODI scores decreased significantly immediately after the procedure and were kept significantly lower than baseline levels during the follow-up periods. No complications occurred perioperatively and during the follow-up periods. 88.6% of patients were satisfied with the procedure. Conclusions. Our preliminary results suggest that endoscope-guided RFA may be alternative option to treat CLBP secondary to SIJ complex.

  1. Endoscopic Radiofrequency Ablation of the Sacroiliac Joint Complex in the Treatment of Chronic Low Back Pain: A Preliminary Study of Feasibility and Efficacy of a Novel Technique

    PubMed Central

    Ryu, Kyeong-Sik; Hur, Jung-Woo; Seong, Ji-Hoon; Cho, Hyun-Jin

    2016-01-01

    Background. Radiofrequency ablation (RFA) is a less invasive technique for treatment of sacroiliac joint (SIJ) pain. Objective. To evaluate the feasibility and efficacy of endoscope-guided RFA for the treatment of CLBP from the SIJ complex. Methods. In this retrospective study, the medical records of 17 patients who underwent endoscope-guided RFA of the SIJ complex were reviewed. A bipolar radiofrequency probe was used to lesion the posterior capsule of the SIJ as well as the lateral branches of S1, S2, S3, and the L5 dorsal ramus in multiple locations. We visualized the ablation area using endoscope. We assessed visual analogue scale (VAS) and the Oswestry disability index (ODI) preoperatively, immediately postop, and at 1-, 3-, and 6-month postop outpatient clinic visits. Patient satisfaction of the procedure was assessed in percentages. Results. The mean duration of operation was 20 to 50 minutes. The mean VAS and the ODI scores decreased significantly immediately after the procedure and were kept significantly lower than baseline levels during the follow-up periods. No complications occurred perioperatively and during the follow-up periods. 88.6% of patients were satisfied with the procedure. Conclusions. Our preliminary results suggest that endoscope-guided RFA may be alternative option to treat CLBP secondary to SIJ complex. PMID:28105414

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

    PubMed Central

    2012-01-01

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

  3. Insufficient radiofrequency ablation promotes epithelial-mesenchymal transition of hepatocellular carcinoma cells through Akt and ERK signaling pathways

    PubMed Central

    2013-01-01

    Background Residual tumor progression after insufficient radiofrequency ablation (RFA) has been recently reported. However, whether epithelial-mesenchymal transition (EMT), which is a key process that drives cancer metastasis, is involved in the tumor progression after insufficient RFA is not well understood. Methods Human hepatocellular carcinoma (HCC) cell lines SMMC7721 and Huh7 were used. Insufficient RFA was simulated using a water bath (47°C 5 min, 10 min, 15 min, 20 min and 25 min gradually). MTT assay was used to evaluate the proliferation of HCC cells in vitro. Migration and invasion of HCC cells were determined by transwell assay. The molecular changes in HCC cells after insufficient RFA were evaluated by western blot. LY294002 and PD98059 were used to treat HCC cells. An ectopic nude mice model and a tail vein metastatic assay were used to evaluate the growth and metastatic potential of SMMC7721 cells in vivo after insufficient RFA. Results SMMC7721 and Huh7 cells after insufficient RFA (named as SMMC7721-H and Huh7-H respectively) exhibited enhanced proliferation, migration and invasion (6.4% and 23.6%, 33.2% and 66.1%, and 44.1% and 57.4% increase respectively) in vitro. Molecular changes of EMT were observed in SMMC7721-H and Huh7-H cells. LY294002 and PD98059 inhibited the EMT of SMMC7721-H and Huh7-H cells. SMMC7721-H cells also exhibited larger tumor size (1440.8 ± 250.3 mm3 versus 1048.56 ± 227.6 mm3) and more lung metastasis (97.4% increase) than SMMC7721 cells in vivo. Higher expression of PCNA, N-cadherin and MMP-2 and MMP-9, was also observed in SMMC7721-H tumors. Conclusions Insufficient RFA could directly promote the invasiveness and metastasis of HCC cells. Insufficient RFA may promote the EMT of HCC cells through Akt and ERK signaling pathways. PMID:24168056

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

    PubMed Central

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

    2016-01-01

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

  5. Endovenous laser with miniphlebectomy for treatment of varicose veins and effect of different levels of laser energy on recanalization. A single center experience.

    PubMed

    Golbasi, Ilhan; Turkay, Cengiz; Erbasan, Ozan; Kemaloğlu, Cemal; Sanli, Suat; Turkay, Mehtap; Bayezid, Ömer

    2015-01-01

    Varicose veins, associated with great saphenous vein (GSV) incompetence, are traditionally treated with conventional surgery. In recent years, minimally invasive alternatives to surgical treatment such as the endovenous laser ablation (EVLA) and radiofrequency (RF) ablation have been developed with promising results. Residual varicose veins following EVLA, regress untouched, or phlebectomy or foam sclerotherapy can be concomitantly performed. The aim of the present study was to investigate the safety and efficacy of EVLA with different levels of laser energy in patients with varicose veins secondary to saphenous vein reflux. From February 2006 to August 2011, 740 EVLA, usually with concomitant miniphlebectomies, were performed in 552 patients. A total of 665 GSV, 53 small saphenous veins (SSV), and 22 both GSV and SSV were treated with EVLA under duplex USG. At 84 patients, bilateral intervention is made. In addition, miniphlebectomy was performed in 540 patients. A duplex ultrasound (US) is performed to patients preoccupying chronic venous insufficiency (with visible varicose veins, ankle edema, skin changes, or ulcer). Saphenous vein incompetence was diagnosed with saphenofemoral, saphenopopliteal, or truncal vein reflux in response to manual compression and release with patient standing. The procedures were performed under local anesthesia with light sedation or spinal anesthesia. Endovenous 980-nm diode laser source was used at a continuous mode. The mean energy applied per length of GSV during the treatment was 77.5 ± 17.0 J (range 60-100 J/cm). An US evaluation was performed at first week of the procedure. Follow-up evaluation and duplex US scanning were performed at 1 and 6 months, and at 1 and 2 years to assess treatment efficacy and adverse reactions. Average follow-up period was 32 ± 4 months (3-55 months). There were one patient with infection and two patients with thrombus extension into the femoral vein after EVLA. Overall occlusion rate was

  6. Incidence of metachronous visible lesions in patients referred for radiofrequency ablation (RFA) therapy for early Barrett's neoplasia: a single-centre experience

    PubMed Central

    Ortiz-Fernández-Sordo, J; Sami, S; Mansilla-Vivar, R; De Caestecker, J; Cole, A; Ragunath, K

    2016-01-01

    Objective Evaluate the incidence of metachronous visible lesions (VLs) in patients referred for radiofrequency ablation (RFA) for early Barrett's neoplasia. Design This study was conducted as part of the service evaluation audit. Setting Tertiary referral centre. Patients All patients with dysplastic Barrett's oesophagus referred for RFA were included for analysis. White light high-resolution endoscopy (HRE), autofluorescence imaging and narrow band imaging were sequentially performed. Endoscopic mucosal resection (EMR) was performed for all VL. Three to six months after EMR, all patients underwent initial RFA and then repeat RFA procedures at three monthly intervals. Interventions All endoscopy reports and final staging by EMR/surgery were evaluated and included for analysis. Results Fifty patients were analysed; median age 73 years, 84% men. 38/50 patients (76%) had a previous EMR due to the presence of VL before referred for ablation; twelve patients had no previous treatment. In total, 151 ablation procedures were performed, median per patient 2.68. Twenty metachronous VL were identified in 14 patients before the first ablation or during the RFA protocol; incidence was 28%. All metachronous lesions were successfully resected by EMR. Upstaging after rescue EMR compared with the initial histology was observed in four patients (28%). Conclusions In total, 28% of patients enrolled in the RFA programme were diagnosed to have metachronous lesions. This high-incidence rate highlights the importance of a meticulous examination to identify and resect any VL before every ablation session. RFA treatment for early Barrett's neoplasia should be performed in tertiary referral centres with HRE and EMR facilities and expertise. PMID:26834956

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

    PubMed Central

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

    2016-01-01

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

  8. Remote Magnetic versus Manual Navigation for Radiofrequency Ablation of Paroxysmal Atrial Fibrillation: Long-Term, Controlled Data in a Large Cohort

    PubMed Central

    Berte, Benjamin; Vandekerckhove, Yves; Tavernier, Rene

    2017-01-01

    Purpose. We aimed to study long-term outcome after pulmonary vein isolation (PVI) guided by remote magnetic navigation (RMN) and provided comparative data to outcome after manual navigation (MAN). Methods. Three hundred thirty-six patients with symptomatic paroxysmal AF underwent PVI by irrigated point-by-point radiofrequency (RF) ablation (RMN, n = 114 versus MAN, n = 222). Patients were followed up with symptom guided rhythm monitoring for a period up to 43 months. The end point of the study was freedom from repeat ablation after a single procedure and without antiarrhythmic drug treatment (ADT). Results. At the end of follow-up (median 26.3 months), freedom from repeat ablation was comparable between RMN and MAN (70.9% versus 69.5%, p = 0.61). At repeat, mean number of reconnected veins was 2.4 ± 1.2 in RMN versus 2.6 ± 1.0 in MAN (p = 0.08). The majority of repeat procedures occurred during the first year (82.1% in RMN versus 78.5% in MAN; p = 0.74). Conclusion. On the long term (up to 3 years) and in a large cohort of patients with paroxysmal AF, RMN-guided PVI is as effective as MAN guided PVI. In both strategies the majority of repeat procedures occurred during the first year after index procedure. PMID:28386560

  9. Automatic classification of scar tissue in late gadolinium enhancement cardiac MRI for the assessment of left-atrial wall injury after radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Perry, Daniel; Morris, Alan; Burgon, Nathan; McGann, Christopher; MacLeod, Robert; Cates, Joshua

    2012-03-01

    Radiofrequency ablation is a promising procedure for treating atrial fibrillation (AF) that relies on accurate lesion delivery in the left atrial (LA) wall for success. Late Gadolinium Enhancement MRI (LGE MRI) at three months post-ablation has proven effective for noninvasive assessment of the location and extent of scar formation, which are important factors for predicting patient outcome and planning of redo ablation procedures. We have developed an algorithm for automatic classification in LGE MRI of scar tissue in the LA wall and have evaluated accuracy and consistency compared to manual scar classifications by expert observers. Our approach clusters voxels based on normalized intensity and was chosen through a systematic comparison of the performance of multivariate clustering on many combinations of image texture. Algorithm performance was determined by overlap with ground truth, using multiple overlap measures, and the accuracy of the estimation of the total amount of scar in the LA. Ground truth was determined using the STAPLE algorithm, which produces a probabilistic estimate of the true scar classification from multiple expert manual segmentations. Evaluation of the ground truth data set was based on both inter- and intra-observer agreement, with variation among expert classifiers indicating the difficulty of scar classification for a given a dataset. Our proposed automatic scar classification algorithm performs well for both scar localization and estimation of scar volume: for ground truth datasets considered easy, variability from the ground truth was low; for those considered difficult, variability from ground truth was on par with the variability across experts.

  10. Radiofrequency ablation and percutaneous permanent iodine-125 implantation as salvage therapy for giant recurrent sclerosing epithelioid fibrosarcoma of the chest wall: A case report

    PubMed Central

    KE, SHAN; DING, XUE-MEI; GAO, JUN; WANG, SHAO-HONG; ZHANG, JUN; KONG, JIAN; SUN, WEN-BING

    2015-01-01

    Sclerosing epithelioid fibrosarcoma (SEF) is a rare soft-tissue sarcoma for which there is no standardized treatment regimen available. The current treatment options for SEF are resection, radiation and chemotherapy. Surgical resection remains the mainstay of therapy for SEF. However, SEF is an aggressive tumor that is prone to repeated local recurrence if not widely excised. Radiation and chemotherapy are less commonly used due to the insensitivity of SEF to these therapies. The treatment of recurrent SEF is even more challenging. The present study describes a patient who presented with a giant recurrent SEF arising from the chest wall that was accompanied by emergent bleeding. The patient was a 70-year-old male who had multiple comorbid diseases, including hypertension and chronic cardiac dysfunction. A computed tomography (CT) scan indicated the involvement of the sternum and anterior mediastinum. However, the patient refused any further surgery. Subsequent to careful discussion and consideration, radiofrequency (RF) ablation and percutaneous iodine-125 implantation was administered. The emergent bleeding was successfully stopped and the tumor was eliminated using RF ablation. Percutaneous iodine-125 implantation under CT guidance established effective control on the growth of the tumor involving the mediastinum. Despite this, the tumor recurred 6 months after treatment. The patient refused any further treatment and was discharged. In conclusion, RF ablation and percutaneous permanent iodine-125 implantation is a feasible and safe salvage therapy for patients with recurrent SEF of the chest wall. PMID:26137032

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

    PubMed Central

    WAN, JUN; WU, WEI; ZHANG, RENQUAN

    2016-01-01

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

  12. Automatic classification of scar tissue in late gadolinium enhancement cardiac MRI for the assessment of left-atrial wall injury after radiofrequency ablation.

    PubMed

    Perry, Daniel; Morris, Alan; Burgon, Nathan; McGann, Christopher; Macleod, Robert; Cates, Joshua

    2012-02-23

    Radiofrequency ablation is a promising procedure for treating atrial fibrillation (AF) that relies on accurate lesion delivery in the left atrial (LA) wall for success. Late Gadolinium Enhancement MRI (LGE MRI) at three months post-ablation has proven effective for noninvasive assessment of the location and extent of scar formation, which are important factors for predicting patient outcome and planning of redo ablation procedures. We have developed an algorithm for automatic classification in LGE MRI of scar tissue in the LA wall and have evaluated accuracy and consistency compared to manual scar classifications by expert observers. Our approach clusters voxels based on normalized intensity and was chosen through a systematic comparison of the performance of multivariate clustering on many combinations of image texture. Algorithm performance was determined by overlap with ground truth, using multiple overlap measures, and the accuracy of the estimation of the total amount of scar in the LA. Ground truth was determined using the STAPLE algorithm, which produces a probabilistic estimate of the true scar classification from multiple expert manual segmentations. Evaluation of the ground truth data set was based on both inter- and intra-observer agreement, with variation among expert classifiers indicating the difficulty of scar classification for a given a dataset. Our proposed automatic scar classification algorithm performs well for both scar localization and estimation of scar volume: for ground truth datasets considered easy, variability from the ground truth was low; for those considered difficult, variability from ground truth was on par with the variability across experts.

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

    SciTech Connect

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

    2007-02-15

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

  14. Treatment Failure After Image-Guided Percutaneous Radiofrequency Ablation (RFA) of Renal Tumors - A Systematic Review with Description of Type, Frequency, Risk Factors and Management.

    PubMed

    Vollherbst, Dominik; Bertheau, Robert; Kauczor, Hans-Ulrich; Radeleff, Boris Alexis; Pereira, Philippe L; Sommer, Christof-Matthias

    2017-03-01

    Background Radiofrequency ablation (RFA) is an established treatment for small renal tumors. The objective of this review is to systematically assess the type, frequency, risk factors and management of treatment failure after image-guided percutaneous RFA of renal tumors. Method 10 studies (967 patients, 1033 tumors) with a mean/median follow-up of ≥ 30 months were systematically identified and analyzed. Results and Conclusion Image-guided percutaneous RFA of localized renal tumors is very effective. The most common type of treatment failure is residual unablated tumor (5.9 %), followed by local tumor progression (4.7 %). De novo tumors in the kidneys occur in 1.3 % of cases and extra-renal metastases in 2.0 %. Local tumor progression, de novo tumors in the kidneys and extra-renal metastases occur predominantly later than 12 months after initial RFA. Tumor size > 3 cm and central tumor location are the major risk factors for treatment failure. In the case of treatment failure, repeated RFA shows high success rates (86.3 % for residual unablated tumors and 87.5 % for local tumor progression). Key Points: · Treatment failure can be subdivided into residual unablated tumor and local tumor progression.. · Residual unablated tumor occurs in 5.9 % of cases.. · Local tumor progression occurs in 4.7 % of cases.. · Tumor size and location are the major risk factors for treatment failure.. · Repeated RFA is effective and commonly used for management.. Citation Format · Vollherbst D, Bertheau R, Kauczor H et al. Treatment Failure After Image-Guided Percutaneous Radiofrequency Ablation (RFA) of Renal Tumors - A Systematic Review with Description of Type, Frequency, Risk Factors and Management. Fortschr Röntgenstr 2017; 189: 219 - 227.

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

    SciTech Connect

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

    2011-02-15

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

  16. “Edgeboost”: A Novel Technique to Extend the Ablation Zone Lateral to a Two-Probe Bipolar Radiofrequency Device

    SciTech Connect

    Huo, Ya Ruth Pillai, Krishna Akhter, Javed Morris, David L.

    2016-01-15

    BackgroundThe dual-electrode bipolar-RFA (B-RFA) is increasingly used to ablate large liver tumours (3–7 cm). However, the challenging aspect of B-RFA is the placement of the two electrodes around the tumour. Realignment often requires the electrodes to be extracted and reinserted.AimThe aim of this study is to examine “Edgeboost”, a novel technique to increase the lateral ablation dimension without requiring any realignment of the electrodes.Methods and MaterialsAn egg-white model and an ex vivo calf liver model were used compare the standard bipolar mode ablation to Edgeboost-1 (reaching full impedance in bipolar mode initially, then cycling in unipolar mode between left and right probes) and Edgeboost-2 (similar to Edgeboost-1 but not reaching full impedance initially in bipolar mode in order to minimize charring and, thus, to increase total ablation time).ResultsA significantly larger outer lateral ablation dimension to the probe was achieved with Edgeboost-1 compared to the standard method in the liver model (1.14 cm, SD: 0.16 vs. 0.44 cm, SD: 0.24, p = 0.04). Edgeboost-2 achieved the largest outer lateral ablation dimension of 1.75 cm (SD: 0.35). A similar association was seen in the egg model. Edgeboost-2 almost doubled the mass ablated with standard bipolar alone (mass ratio: 1:1.94 in egg white and 1:1.84 in liver).ConclusionThis study demonstrates that the novel “Edgeboost” technique can increase the outer lateral ablation dimension without requiring the two inserted electrodes to be reinserted. This would be beneficial for interventionists who use the dual B-RFA.

  17. Systemic inflammatory response and downmodulation of peripheral CD25+Foxp3+ T-regulatory cells in patients undergoing radiofrequency thermal ablation for lung cancer.

    PubMed

    Fietta, Anna Maria; Morosini, Monica; Passadore, Ileana; Cascina, Alessandro; Draghi, Paola; Dore, Roberto; Rossi, Sandro; Pozzi, Ernesto; Meloni, Federica

    2009-07-01

    Radiofrequency thermal ablation (RFTA) is a local tumor-destructing technique that can potentially modulate the host immune response through mechanisms that are not clearly defined. We assessed whether RFTA could affect multiple systemic inflammatory and immunological parameters, including CD25+Foxp+ cells, in patients with primary or metastatic lung tumors. Three days after RFTA, a moderate and temporary systemic inflammatory response developed, as demonstrated by the increase in peripheral neutrophils and monocytes and in plasma levels of proinflammatory chemokines (MIP-1alpha, MIP-1beta, eotaxin, and interleukin[IL]-8) and acute phase reactants (complement C3 and C4, serum amyloid, alpha1 antichymotrypsin, and C-reactive protein). Moreover, we found a concomitant release of the anti-inflammatory factor IL-10. Thirty days after RFTA, a significant reduction in CD25+Foxp3+ counts with an increase in CD4+ T-cell proliferation and number of interferon-gamma-secreting cells was observed. The reduction in CD25+Foxp3+ cells lasted up to 90 days after treatment. The use of RFTA in lung cancer patients has an immunomodulatory activity: it induces a self-limiting systemic inflammation early and later a reduction of circulating CD25+Foxp3+ Tregs. In addition to tumor ablation, downmodulation of this regulatory subset might be an important mechanism involved in the long-term clinical efficacy of RFTA.

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

    SciTech Connect

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

    2009-01-15

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

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

    PubMed Central

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

    2008-01-01

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

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

    PubMed Central

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

    2016-01-01

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