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At least 19 recordsLinked to original sources
PubMed2005

Hepatic hemorrhage caused by percutaneous tumor ablation: radiofrequency ablation versus cryoablation in a porcine model.

PURPOSE: To determine the extent of hepatic hemorrhage caused by percutaneous cryoablation performed with a small-diameter cryoablation probe compared with that caused by percutaneous radiofrequency (RF) ablation in a porcine model. MATERIALS AND METHODS: The study was pre-approved by the institutional research animal care and use committee, and husbandry and experiments complied with National Institutes of Health standards for care and use of laboratory animals. Percutaneous hepatic ablation was performed in 18 domestic pigs (mean weight, 45 kg) by using a 17-gauge (1.5-mm-diameter) RF electrode (n = 6), a cluster of three RF electrodes (n = 6), or a 13-gauge (2.4 mm-diameter) cryoprobe (n = 6). Ablation was performed in four sites per liver. Total blood loss, minimum lesion diameter, maximum lesion diameter, and lesion volume were determined for each group and compared by using analysis of variance. RESULTS: Mean blood loss was 11.11 mL +/- 11.47 (standard deviation), 105.29 mL +/- 175.58, and 28.06 mL +/- 30.97 with the single RF electrode, RF electrode cluster, and cryoablation probe, respectively. Mean minimum and maximum lesion diameters were largest with the RF electrode cluster (2.40 and 3.98 cm, respectively), followed by the cryoablation probe (2.38 and 3.94 cm) and single RF electrode (1.49 and 2.63 cm). Mean minimum and maximum lesion diameters were significantly different between the single RF electrode and the RF electrode cluster, as well as between the single RF electrode and the cryoablation probe (P < .001). Mean lesion volume was largest for the RF electrode cluster (24.03 cm3), followed by those for the cryoablation probe (17.46 cm3) and single RF electrode (9.05 cm3) (single RF electrode vs cryoablation probe, P < .05). Lesion volumes were not significantly different with the RF electrode cluster versus the single RF electrode (P = .052) or with the RF electrode cluster versus the cryoablation probe (P = .381). CONCLUSION: Mean blood loss from percutaneous cryoablation in this model was between that for RF ablation with the single electrode and that for RF ablation with the electrode cluster.

Analysis of Variance↗
PubMedDate not supplied

Comparison of wet radiofrequency ablation with dry radiofrequency ablation and radiofrequency ablation using hypertonic saline preinjection: ex vivo bovine liver.

OBJECTIVE: We wished to compare the in-vitro efficiency of wet radiofrequency(RF) ablation with the efficiency of dry RF ablation and RF ablation with preinjection of NaCl solutions using excised bovine liver. MATERIALS AND METHODS: Radiofrequency was applied to excised bovine livers in a monopolar mode for 10 minutes using a 200 W generator and a perfused-cooled electrode with or without injection or slow infusion of NaCl solutions. After placing the perfused-cooled electrode in the explanted liver, 50 ablation zones were created with five different regimens: group A; standard dry RF ablation, group B; RF ablation with 11 mL of 5% NaCl solution preinjection, group C; RF ablation with infusion of 11 mL of 5% NaCl solution at a rate of 1 mL/min, group D; RFA with 6 mL of 36% NaCl solution preinjection, group E; RF ablation with infusion of 6 mL of 36% NaCl solution at a rate of 0.5 mL/min. In groups C and E, infusion of the NaCl solutions was started 1 min before RF ablation and then maintained during RF ablation (wet RF ablation). During RF ablation, we measured the tissue temperature at 15 mm from the electrode. The dimensions of the ablation zones and changes in impedance, current and liver temperature during RF ablation were then compared between the groups. RESULTS: With injection or infusion of NaCl solutions, the mean initial tissue impedance prior to RF ablation was significantly less in groups B, C, D, and E (43-75 ohm) than for group A (80 ohm) (p < 0.05). During RF ablation, the tissue impedance was well controlled in groups C and E, but it was often rapidly increased to more than 200 ohm in groups A and B. In group D, the impedance was well controlled in six of ten trials but it was increased in four trials (40%) 7 min after starting RF ablation. As consequences, the mean current was higher for groups C, D, and E than for the other groups: 401+/-145 mA in group A, 287+/-32 mA in group B, 1907+/-96 mA in group C, 1649+/-514 mA in group D, and 1968+/-108 mA in group E (p< 0.05). In addition, the volumes of RF-induced coagulation necrosis were greater in groups C and E than in group D, which was greater than in groups A and B than in group E (p < 0.05); 14.3+/-3.0 cm(3) in group A; 12.4+/-3.8 cm(3) in group B; 80.9+/-9.9 cm(3) in group C; 45.3+/-11.3 cm(3) in group D and 81.6+/-8.6 cm(3) in group E. The tissue temperature measured at 15 mm from the electrode was higher in groups C, D and E than other groups (p < 0.05): 53+/-12 degrees C in group A, 42+/-2 degrees C in group B, 93+/-8 degrees C in group C; 79+/-12 degrees C in group D and 83+/-8 degrees C in group E. CONCLUSION: Wet RF ablation with 5% or 36% NaCl solutions shows better efficiency in creating a large ablation zone than does dry RF ablation or RF ablation with preinjection of NaCl solutions.

Animals↗
PubMedDate not supplied

Scope and efficacy of complex radiofrequency ablation.

Radiofrequency ablation is an effective treatment for various tachycardias. In some patients undergoing radiofrequency ablation, there are additional complexities. Of 254 consecutive patients (161 males, 93 females, aged 38 +/- 15 years) who underwent radiofrequency ablation, two groups were identified. Patients with structural heart disease, multiple accessory pathways, multifocal idiopathic ventricular tachycardia, parahisian accessory pathways, and multiple mechanisms of tachycardia were considered as complex radiofrequency ablation (Group I) and the remaining as non-complex radiofrequency ablation (Group II). There were 23 patients in Group I. The overall success rate was not different in the two groups: 20/23 (87%) vs 208/231 (90%) in groups I and II, respectively. The procedure and fluoroscopy time (212 +/- 91 min vs 136 +/- 45 min; p = 0.0001; and 55 +/- 31 min vs 31 +/- 21 min; p = 0.001, respectively) were significantly longer in Group I. There was a higher recurrence rate in Group I (6/20, 30% vs 20/208, 9.6%; p = 0.02); repeat radiofrequency ablation was successfully performed in four patients with recurrence in Group I. Complications were rare in both the groups. There was no mortality. Thus radiofrequency ablation in complex situations was effective, though more demanding than non-complex radiofrequency ablation and associated with higher recurrence.

Adolescent↗
PubMed2005

Comparison between combination therapy of percutaneous ethanol injection and radiofrequency ablation and radiofrequency ablation alone for patients with hepatocellular carcinoma.

AIM: In the present study, the characteristics of PEI-RFA treatment were further elucidated by analyzing the relationship between the volume of coagulated necrosis and the energy requirement for ablation or the amount of ethanol injected into HCC. METHODS: The volume of coagulated necrosis, total energy requirement and energy requirement for coagulation of per unit volume were examined in the groups of PEI-RFA and RFA alone using the Cool-tip RF system. RESULTS: The results showed that the volume of coagulated necrosis induced was significantly larger in PEI-RFA group than in routine RFA group, when the total energy administered was comparable in both groups. In PEI-RFA, enlargement of coagulated necrosis was admitted in 3 dimensions and the amount of energy requirement per unit volume of coagulated necrosis was negatively correlated with the amount of ethanol injected into HCC. CONCLUSION: These results suggest that, compared to RFA alone, PEI-RFA enables to induce comparable coagulated necrosis with smaller energy requirement, and that PEI-RFA is likely to be less invasive than RFA alone irrespective of inducing enhanced coagulated necrosis. Thus, simple prior injection of ethanol may make RFA treatment more effective and less invasive for the treatment of patients with HCC.

Administration, Cutaneous↗
PubMedDate not supplied

Development of an in vivo tumor-mimic model for learning radiofrequency ablation.

Radiofrequency ablation requires accurate probe placement using ultrasound guidance. The purpose of this study was to develop an in vivo tumor-mimic model for learning open and laparoscopic radiofrequency ablation. Tumor-mimics were created in ex vivo porcine livers by injecting a mixture of 3% agarose, 3% cellulose, 7% glycerol, and 0.05% methylene blue, which formed 1 cm hyperechoic, discrete lesions on ultrasound. Open and laparoscopic (using a box-trainer) ablation techniques were practiced. In vivo experiments were then conducted in 10 pigs. Three tumor-mimics were created in each animal using a laparoscopic approach. Lesions were characterized sonographically, ablated using an open (n = 5) or laparoscopic (n = 5) approach, and examined pathologically. An ablation in normal liver tissue was performed as a control. Tissue impedance was recorded. Target creation took 81 minutes per animal and 96% of injections were successful. Tissue impedance (48.8 +/- 5.8 vs. 49.6 +/- 5.4) and ablation size (25.1 +/- 3.4 vs. 24.3 +/- 5.1) were not significantly different for controls (n = 8) and tumor-mimics (n = 26), respectively. One animal died of a pulmonary embolism following injection of agarose into a hepatic vein. The agarose-based tissue-mimic creates realistic sonographic targets for learning ultrasound-guided open and laparoscopic radiofrequency ablation in an in vivo model.

Animals↗
PubMed2000

Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm.

BACKGROUND: Thermal ablation of unresectable hepatic tumors can be achieved by cryosurgical ablation (CSA) or radiofrequency ablation (RFA). The relative advantages and disadvantages of each technique have not yet been determined. HYPOTHESIS: Radiofrequency ablation of malignant hepatic neoplasms can be performed safely, but is currently limited by size. Cryosurgical ablation, while associated with higher morbidity, is more effective for larger unresectable hepatic malignant neoplasms. DESIGN: Retrospective analysis of prospective patient database. PATIENTS AND METHODS: Between July 1992 and September 1999, 308 patients with liver tumors not amenable to curative surgical resection were treated with CSA and/or RFA (percutaneous, laparoscopic, celiotomy). No patient had preoperative evidence of extrahepatic disease. All patients underwent laparoscopy with intraoperative ultrasound if technically possible. Both RFA and CSA were performed under ultrasound guidance. Resection, as an adjunctive procedure, was combined with ablation in certain patients. RESULTS: Laparoscopy identified extrahepatic disease in 12% of patients, and intraoperative hepatic ultrasound identified additional lesions in 33% of patients, despite extensive preoperative imaging. Radiofrequency ablation alone or combined with resection or CSA resulted in reduced blood loss (P<.05), thrombocytopenia (P<.05), and shorter hospital stay compared with CSA alone (P<.05). Median ablation times for lesions greater than 3 cm were 60 minutes with RFA and 15 minutes with CSA (P<.001). Local recurrence rates for lesions greater than 3 cm were also greater with RFA (38% vs 17%). CONCLUSIONS: Laparoscopy and intraoperative ultrasound are essential in staging patients with hepatic malignant neoplasms. Radiofrequency ablation when combined with CSA reduces the morbidity of multiple freezes. Although RFA is safer than CSA and can be performed via different approaches (percutaneously, laparoscopically, or at celiotomy), it is limited by tumor size (<3 cm). Percutaneous RFA should be considered in high-risk patients or those with small local recurrences.

Catheter Ablation↗
PubMedDate not supplied

Saline infusion markedly reduces impedance and improves efficacy of pulmonary radiofrequency ablation.

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 ohms, respectively. With the saline infusion the impedance was 71.3 +/- 22 ohms and 103.6 +/- 37.5 ohms. The effect of this was significantly larger volume of ablation using the saline infusion during percutaneous RFA (90.6 +/- 23 cm3 vs 10.47 +/- 2.9 cm3, p = 0.01) and open RFA (107.8 +/- 25.8 cm3 vs 24.9 +/- 19.3 cm3, p = 0.0002). Saline infusion during RFA is associated with lower impedance, higher power delivery and larger lesion size.

Animals↗
PubMed2006

A case of splenic abscess after radiofrequency ablation.

Radiofrequency ablation (RFA) is an innovative technique used primarily for the palliative treatment of unresectable liver tumors. Its therapeutic indications however, have been expanded and now include various other organs and diseases. There is a paucity of data regarding technical details and complications of the use of RFA in the spleen. We report a case of partial splenectomy using radiofrequency ablation for splenic hydatid disease, complicated by an abscess formation.

Abscess↗
PubMed2003

Catheter intramural needle radiofrequency ablation creates deeper lesions than irrigated tip catheter ablation.

Radiofrequency ablation of the left ventricle using an endocardially placed electrode is unable to reliably create transmural lesions even with active electrode cooling. To produce deeper radiofrequency lesions, the authors developed and tested a prototype intramural needle ablation catheter that had a distal 1.1-mm diameter straight needle that could be advanced 12 mm into the myocardium. Freshly excised hearts from eight male sheep were perfused and superfused with oxygenated ovine blood. Ablations were performed for 60 seconds with the prototype catheter and a conventional 5-mm irrigated tip ablation catheter at target temperatures of 90 degrees C and 50 degrees C, respectively. The ablation lesions were bisected and stained with blue tetrazolium to assess lesion geometry. The irrigated tip ablation catheter required significantly more power than the intramural needle ablation catheter (37.7 +/- 7.3 vs 6.4 +/- 2.1 W, P < 0.01). Intramural needle lesions were significantly deeper (12.5 +/- 3.0 mm vs 8.3 +/- 2.1 mm, P < 0.01) but less wide (3.9 +/- 1.1 mm vs 11.5 +/- 2.0 mm, P < 0.01) than irrigated tip lesions. There was a high incidence of crater formation (74%), popping (45%), and myocardial charring (29%) during irrigated tip ablation; these phenomena were not observed during intramural needle ablation. The intramural needle ablation catheter creates significantly deeper but narrower lesions without evidence of tissue boiling. This technology may be particularly useful for ablation of ventricular tachycardia originating from regions where tissue depth is increased, like the ventricular septum.

Analysis of Variance↗
PubMedDate not supplied

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

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

Animals↗
PubMed2004

Real-time calibration of temperature estimates during radiofrequency ablation.

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.

Algorithms↗
PubMedDate not supplied

Influencing factors for recurrence of hepatocellular carcinoma treated with radiofrequency ablation.

Radiofrequency ablation (RFA), a new local therapy, has recently been developed for hepatocellular carcinoma (HCC). In this study, we have checked for the factors influencing the recurrence of HCC following RFA. We gave special emphasis to complete coagulation. The study population was comprised of 47 patients (80 tumors) with HCC with tumor size of <3 cm in maximal diameter. The patients were observed for a period of 2-3 years (average 865 days). The local recurrence rate was 19% at the end of 1 year, and 21% by the end of 2 years. The patients with local recurrence received significantly fewer RFA sessions (P<0.05) compared to patients with no recurrence. The frequencies of complete coagulation were significantly less (P<0.05) in patients with local recurrence than patients without local recurrence. The distant recurrence rate was 38% at 1 year, and 60% at 2 years. Patients with distant recurrence had significantly increased number of tumors (2.0+/-1.4) (P<0.05) compared to patients without distant recurrence (1.2+/-0.4). In conclusion, obtaining complete coagulation is an important factor to prevent local recurrence and the number of tumors predicted the distant recurrence in patients with HCC undergoing RFA.

Adult↗
PubMed2026

Comparing the Efficacy of Mechanochemical Ablation Versus Radiofrequency Ablation for Treating Great Saphenous Vein Incompetence: A Meta-Analysis.

BACKGROUND: The objective of this meta-analysis was to compare the efficacy of mechanochemical ablation (MOCA) and radiofrequency ablation (RFA) in the treatment of great saphenous vein (GSV) incompetence. METHODS: Online databases including PubMed, Cochrane Library, Embase, and Web of Science were searched to collect randomized controlled trials (RCTs) and cohort studies comparing MOCA and RFA in the treatment of varicose veins in lower extremities from database inception to October 2025. Primary outcome was anatomic success. Secondary outcomes were visual analog scale (VAS), Aberdeen Varicose Vein Questionnaire score (AVVQ), and complications. Two reviewers independently screened the retrieved literature, extracted data, and assessed the risk of bias in the included studies. Subsequent analysis was performed using RevMan 5.3. RESULTS: A total of four RCTs, one cohort study and retrospective cross-sectional study involving 737 patients (380 MOCA patients and 357 RFA patients) were included. The meta-analysis results showed that the RFA group was significantly better than the MOCA group in short term and long term of anatomical success rate [(odds ratio [OR] = 0.38; 95% confidence interval [CI] (0.20, 0.71), P = 0.003), (OR = 0.17, 95% CI (0.06, 0.45), P = 0.0003)], but patients in the MOCA group had significantly lower perioperative period pain (mean difference [MD] = -4.48, 95% CI (-7.58, -1.37), P = 0.005] and required fewer days to return to normal activities (MD = -0.76, 95% CI, (-0.95, -0.57), P < 0.001). No significant differences were observed between the two groups in minor and major complications [(OR = 0.93, 95% CI (0.66, 1.33), P = 0.70), (OR = 1.30, 95% CI (0.32, 5.28), P = 0.72)] or quality of life scores (MD = -0.45, 95% CI (-2.53 to 1.63), P = 0.67). CONCLUSION: MOCA of GSV incompetence is an effective and safe method. Compared with RFA, it has lower postoperative pain score and faster recovery time. However, the anatomical success rates were significantly lower with MOCA than with RFA. Therefore, long-term follow-up to evaluate the impact on clinical results is required.

Humans↗
PubMed2003

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

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.

Animals↗
PubMed2005

Concepts, considerations, and concerns on the cutting edge of radiofrequency ablation.

Radiofrequency (RF) ablation is rapidly expanding from a tool to treat isolated hepatic malignancy to a therapy for patients with renal, adrenal, skeletal, breast, lung, and other soft-tissue neoplasms. The purpose of this article is to review the status of RF ablation outside the liver and lung and compare outcomes with current clinical standards when appropriate. The author also reviews how differences in local tissue environments play a role in creation of a thermal lesion and achievement of subsequent clinical success.

Catheter Ablation↗
PubMed2006

Lung cancer and radiofrequency ablation.

Radiofrequency (RF) ablation is a recently developed technique for image-guided local destruction of selected tumors. Because the lung is a common site for cancer and usually has substantial functional reserve, RF ablation of lung cancers is an attractive option for minimally invasive treatment. The primary goal of the present review is to describe the natural history, staging systems, and conventional therapies for primary and secondary treatment of lung cancer, as well as the results of RF ablation in animal models and in humans for pulmonary applications, to clarify the appropriate role and limitations of this technology. The secondary goals are to review the principles of how RF works and to describe RF ablation techniques to familiarize interventionalists who may consider incorporating this technology into their practice and inform diagnostic radiologists of expected imaging findings and clinicians of their patients' anticipated courses and outcomes.

Animals↗
PubMed2006

Investigation of the influence of blood flow rate on large vessel cooling in hepatic radiofrequency ablation.

Radiofrequency (RF) ablation using high-frequency current has become an important treatment method for patients with non-resectable liver tumors. Tumor recurrence is associated with tissue cooling in the proximity of large blood vessels. This study investigated the influence of blood flow rate on tissue temperature and lesion size during monopolar RF ablation at a distance of 10 mm from single 4- and 6-mm vessels using two different approaches: 1) an ex vivo blood perfusion circuit including an artificial vessel inserted into porcine liver tissue was developed; and 2) a finite element method (FEM) model was created using a novel simplified modeling technique for large blood vessels. Blood temperatures at the inflow/outflow of the vessel and tissue temperatures at 10 and 20 mm from the electrode tip were measured in the ex vivo set-up. Tissue temperature, blood temperature and lesion size were analyzed under physiological, increased and reduced blood-flow conditions. The results show that changes in blood flow rate in large vessels do not significantly affect tissue temperature and lesion size far away from the vessel. Monopolar ablation could not produce lesions surrounding the vessel due to the strong heat-sink effect. Simulated tissue temperatures correlated well with ex vivo measurements, supporting the FEM model.

Animals↗