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Zidde DH, Sampaio FJ, De Souza DB, Pereira-Sampaio MA. The bovine kidney as an experimental model: Simulated partial nephrectomy of the cranial pole and proportional analysis of the arterial segments. Anat Rec (Hoboken) 2020; 304:1266-1274. [PMID: 33103359 DOI: 10.1002/ar.24552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/03/2020] [Accepted: 09/12/2020] [Indexed: 11/09/2022]
Abstract
Previous studies have shown that the pig kidney is not a good model for some procedures. This study aimed to describe the relationship between the collecting system and the intrarenal arteries, the arterial segments, and to evaluate the bovine kidney as an experimental model for partial nephrectomy of the cranial pole. Polyester resin endocasts of the kidney collecting system together with the intrarenal arteries were prepared. Thirty-two kidneys were used to evaluate the relationship between the collecting system and the intrarenal arteries, while 25 kidneys were transversally sectioned at different points to simulate partial nephrectomy of the cranial pole. Polyester resin of different colors was injected into each segmental artery of the 24 kidneys to evaluate the arterial segments proportionally. The renal artery was divided into cranial and caudal primary branches in 75% of the cases. The cranioventral branch curved on the cranial pole and ran toward the ventral mid-zone in 56.3% of the cases, resembling the retropelvic artery of the human kidney. The kidney was divided into two (25%) or three (75%) arterial segments. The caudal arterial segment had the highest proportional volume (62%). The cranioventral branch was damaged in 28.6% of the kidneys sectioned 1 cm inside the hilum. The arterial branching pattern, the arterial segmentation, and the impairment of the arterial supply after the simulated partial nephrectomy of the cranial pole are quite different from those found in humans. Thus, all differences should be taken into account when using the bovine kidney as a model.
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Affiliation(s)
- Daniel H Zidde
- Urogenital Research Unit, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Francisco J Sampaio
- Urogenital Research Unit, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Diogo B De Souza
- Urogenital Research Unit, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marco A Pereira-Sampaio
- Urogenital Research Unit, State University of Rio de Janeiro, Rio de Janeiro, Brazil.,Department of Morphology, Fluminense Federal University, Rio de Janeiro, Brazil
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Testoni SGG, Healey AJ, Dietrich CF, Arcidiacono PG. Systematic review of endoscopy ultrasound-guided thermal ablation treatment for pancreatic cancer. Endosc Ultrasound 2020; 9:83-100. [PMID: 32295966 PMCID: PMC7279078 DOI: 10.4103/eus.eus_74_19] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The development of curvilinear-array EUS and EUS-guided fine-needle aspiration (EUS-FNA) has led these approaches to become interventional procedures rather than purely diagnostic, as a minimally invasive antitumor therapeutic alternative to radiological and surgical treatments. The possibility to accurately position needle devices and to reach a deep target like the pancreas gland under real-time imaging guidance has expanded the use of EUS to ablate tumors. Currently, a variety of probes specifically designed for EUS ablation are available, including radiofrequency, hybrid cryothermal ablation (combining radiofrequency with cryotechnology), photodynamic therapy, and laser ablation. To date, several studies have demonstrated the safety and feasibility of these ablation techniques in the pancreatic setting, but only a few small series on pancreatic thermal ablation under EUS guidance are available. EUS-guided thermal ablation is primarily used for pancreatic cancer. It is well suited to this disease because of its superior anatomical access compared with other imaging modalities and the dismal prognosis despite improvements in chemoradiotherapy and surgery in the management of pancreatic cancer. Other targets are pancreatic neuroendocrine tumors and pancreatic cystic neoplasms, which are curable by surgical resection, but some patients are poor surgical candidates or prefer conservative management. This is a literature review of previously published clinical studies on EUS-guided thermal ablative therapies. Data on the long-term efficacy of EUS-guided antitumor thermal ablation therapy and large prospective randomized studies are still needed to confirm the real clinical benefits of these techniques for the management of pancreatic neoplasms.
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Affiliation(s)
- Sabrina Gloria Giulia Testoni
- Division of Pancreato-Biliary Endoscopy and Endosonography, Pancreas Translational and Clinical Research Center, San Raffaele Scientific Institute IRCCS, Vita-Salute San Raffaele University, Milan, Italy
| | - Andrew James Healey
- Department of Clinical Surgery, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, Scotland
| | - Christoph F Dietrich
- Department of Internal Medicine, Hirslanden Hospitals Berne Beau Site, Salem and Permanence, Berne, Switzerland
| | - Paolo Giorgio Arcidiacono
- Division of Pancreato-Biliary Endoscopy and Endosonography, Pancreas Translational and Clinical Research Center, San Raffaele Scientific Institute IRCCS, Vita-Salute San Raffaele University, Milan, Italy
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Chaudhary S, Sun SY. Endoscopic ultrasound-guided radiofrequency ablation in gastroenterology: New horizons in search. World J Gastroenterol 2017; 23:4892-4896. [PMID: 28785143 PMCID: PMC5526759 DOI: 10.3748/wjg.v23.i27.4892] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 04/30/2017] [Accepted: 06/12/2017] [Indexed: 02/06/2023] Open
Abstract
Radiofrequency ablation (RFA) has been widely used for the treatment of various solid organ malignancies. Over the last decade, endosonographers have gradually shifted the application of RFA from porcine models to humans to treat a spectrum of diseases. RFA is performed in patients with pancreatic carcinoma who are not candidates for surgery. In this paper, we will discuss various indications for RFA, its procedural details and complications. At present, endoscopic ultrasound-guided RFA is gradually incorporated into the management of various diseases and opens a new avenue for disease treatment.
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Signoretti M, Valente R, Repici A, Delle Fave G, Capurso G, Carrara S. Endoscopy-guided ablation of pancreatic lesions: Technical possibilities and clinical outlook. World J Gastrointest Endosc 2017; 9:41-54. [PMID: 28250896 PMCID: PMC5311472 DOI: 10.4253/wjge.v9.i2.41] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 10/12/2016] [Accepted: 12/09/2016] [Indexed: 02/05/2023] Open
Abstract
Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP)-guided ablation procedures are emerging as a minimally invasive therapeutic alternative to radiological and surgical treatments for locally advanced pancreatic cancer (LAPC), pancreatic neuroendocrine tumours (PNETs), and pancreatic cystic lesions (PCLs). The advantages of treatment under endoscopic control are the real-time imaging guidance and the possibility to reach a deep target like the pancreas. Currently, radiofrequency probes specifically designed for ERCP or EUS ablation are available as well as hybrid cryotherm probe combining radiofrequency with cryotechnology. To date, many reports and case series have confirmed the safety and feasibility of that kind of ablation technique in the pancreatic setting. Moreover, EUS-guided fine-needle injection is emerging as a method to deliver ablative and anti-tumoral agents inside the tumuor. Ethanol injection has been proposed mostly for the treatment of PCLs and for symptomatic functioning PNETs, and the use of gemcitabine and paclitaxel is also interesting in this setting. EUS-guided injection of chemical or biological agents including mixed lymphocyte culture, oncolytic viruses, and immature dendritic cells has been investigated for the treatment of LAPC. Data on the long-term efficacy of these approaches, and large prospective randomized studies are needed to confirm the real clinical benefits of these techniques for the management of pancreatic lesions.
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Estimation of saline-mixed tissue conductivity and ablation lesion size. Comput Biol Med 2013; 43:504-12. [DOI: 10.1016/j.compbiomed.2013.02.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 12/13/2012] [Accepted: 02/18/2013] [Indexed: 12/27/2022]
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Endoscopic Ultrasound-Guided Radiofrequency Ablation (EUS-RFA) of the Pancreas in a Porcine Model. Gastroenterol Res Pract 2012; 2012:431451. [PMID: 23049547 PMCID: PMC3459266 DOI: 10.1155/2012/431451] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 08/21/2012] [Indexed: 02/07/2023] Open
Abstract
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.
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CT-guided Bipolar and Multipolar Radiofrequency Ablation (RF Ablation) of Renal Cell Carcinoma: Specific Technical Aspects and Clinical Results. Cardiovasc Intervent Radiol 2012; 36:731-7. [DOI: 10.1007/s00270-012-0468-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 07/29/2012] [Indexed: 12/16/2022]
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Yarmolenko PS, Moon EJ, Landon C, Manzoor A, Hochman DW, Viglianti BL, Dewhirst MW. Thresholds for thermal damage to normal tissues: an update. Int J Hyperthermia 2011; 27:320-43. [PMID: 21591897 DOI: 10.3109/02656736.2010.534527] [Citation(s) in RCA: 415] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The purpose of this review is to summarise a literature survey on thermal thresholds for tissue damage. This review covers published literature for the consecutive years from 2002-2009. The first review on this subject was published in 2003. It included an extensive discussion of how to use thermal dosimetric principles to normalise all time-temperature data histories to a common format. This review utilises those same principles to address sensitivity of a variety of tissues, but with particular emphasis on brain and testis. The review includes new data on tissues that were not included in the original review. Several important observations have come from this review. First, a large proportion of the papers examined for this review were discarded because time-temperature history at the site of thermal damage assessment was not recorded. It is strongly recommended that future research on this subject include such data. Second, very little data is available examining chronic consequences of thermal exposure. On a related point, the time of assessment of damage after exposure is critically important for assessing whether damage is transient or permanent. Additionally, virtually no data are available for repeated thermal exposures which may occur in certain recreational or occupational activities. For purposes of regulatory guidelines, both acute and lasting effects of thermal damage should be considered.
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Affiliation(s)
- Pavel S Yarmolenko
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
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Pozzi-Mucelli R, Faccioli N, Manfredi R. Imaging findings of genitourinary tumors in the elderly. Radiol Clin North Am 2008; 46:773-84, vi. [PMID: 18922292 DOI: 10.1016/j.rcl.2008.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Aging-correlated pathologies are atherosclerosis, arterial hypertension, diabetes mellitus, bacterial infections, and malnutrition. The progressive impairment of renal function is the cause of the drug-induced renal pathologies: direct damage induced by nephrotoxic drugs or indirect damage induced by decreased renal excretion of serum molecules. In the elderly, an increase in different pathologies occurs in the genitourinary tract. Among these pathologies, an increase in neoplastic disorders is present; at the same time, several non-neoplastic pathologies are more frequent in old patients. This article considers first the neoplastic genitourinary pathologies and second the non-neoplastic genitourinary pathologies.
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Affiliation(s)
- Roberto Pozzi-Mucelli
- Department of Radiology, G.B. Rossi Hospital, University of Verona, Piazzale Scuro 10, 37134 Verona, Italy.
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Lee JM, Han JK, Kim SH, Son KR, Kim HC, Kim SJ, Choi BI. In Vivo Efficiency of Multipolar Radiofrequency Ablation with Two Bipolar Electrodes: A Comparative Experimental Study in Pig Kidney. J Vasc Interv Radiol 2007; 18:1553-60. [DOI: 10.1016/j.jvir.2007.08.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Ni Y, Mulier S, Chen F, Lescroart O, Roelants I, Marchal G. Radiofrequency ablation: the use of appropriate terms and the citation of prior art. Acad Radiol 2006; 13:1047-8; author reply 1048-9. [PMID: 16843859 DOI: 10.1016/j.acra.2006.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Revised: 03/23/2006] [Accepted: 06/15/2006] [Indexed: 01/17/2023]
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Lee JM, Han JK, Chang JM, Chung SY, Kim SH, Lee JY, Choi BI. Radiofrequency ablation in pig lungs: in vivo comparison of internally cooled, perfusion and multitined expandable electrodes. Br J Radiol 2006; 79:562-71. [PMID: 16823060 DOI: 10.1259/bjr/51844219] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The purpose of this study was to compare the amounts of in vivo coagulation obtained by radiofrequency (RF) ablation in porcine lung, using three types of electrodes. 15 in vivo ablation procedures were performed in the lungs of five pigs using three kinds of currently available RF devices under CT guidance. After placing an electrode in the lung, three ablation zones were created at each of three different regimens: Group A: RF ablation with an internally cooled electrode; Group B: RF ablation with a perfusion electrode, with instillation of 0.9% NaCl solution at a rate of 1.5 ml min(-1); Group C: RF ablation with a multitined expandable electrode. According to the manufacturer's recommendations, RF application times were 12 min in group A and 20 min in group B. In group C, RF energy was delivered for 7 min after a mean temperature of 110 degrees C was reached at 5 cm deployment. 36 min after the procedures, contrast-enhanced CT scans were obtained to evaluate the volume of zone of coagulation, and lungs were harvested for gross measurements. After macroscopic and histopathological analyses of 5 mm-thick lung sections, diameters, volumes and variation coefficients of regions of central coagulation were assessed. During RF ablation, the perfusion electrode allowed a larger energy delivery than the internally cooled or the multitined expandable electrodes, i.e. 33.6+/-4.7 kJ in group A, 40.0+/-8.2 kJ in group B and 23.5+/-6.1 kJ in group C (p<0.05). On gross observation, the cut surface of the gross specimen containing RF-induced coagulation showed that the ablated tissue appeared to be a central, firm, dark-brown area surrounded by an irregular outer margin (approximately 3-10 mm thick) of bright red tissue. In vivo studies showed that RF ablation using the perfusion electrode achieved larger coagulation volume than RF ablation using the other electrodes (p<0.05): 7.2+/-4.1 cm3 in group A; 16.9+/-5.5 cm3 in group B; 7.5+/-3.3 cm3 in group C. The corresponding variation coefficients were 0.55, 0.31, and 0.45, respectively. Our study shows that RF ablation using a perfusion electrode achieves a larger coagulation volume with an irregular margin than RF ablation using internally cooled or multitined expandable electrodes in the porcine lung.
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Affiliation(s)
- J M Lee
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744
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Lee JM, Han JK, Lee JY, Kim SH, Choi JY, Lee MW, Choi SH, Eo H, Choi BI. Hepatic radiofrequency ablation using multiple probes: ex vivo and in vivo comparative studies of monopolar versus multipolar modes. Korean J Radiol 2006; 7:106-17. [PMID: 16799271 PMCID: PMC2667583 DOI: 10.3348/kjr.2006.7.2.106] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2005] [Accepted: 12/16/2005] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE We wanted to compare the efficiency of multipolar radiofrequency ablation (RFA) using three perfused-cooled electrodes with multiple overlapping and simultaneous monopolar techniques for creating an ablation zone in ex vivo bovine livers and in in vivo porcine livers. MATERIALS AND METHODS In the ex vivo experiments, we used a 200 W generator (Valleylab, CC-3 model) and three perfused-cooled electrodes or internally cooled electrodes to create 30 coagulation zones by performing consecutive monopolar RFA (group A, n = 10), simultaneous monopolar RFA (group B, n = 10) or multipolar RFA (group C, n = 10) in explanted bovine livers. In the consecutive mode, three ablation spheres were created by sequentially applying 150 watts radiofrequency (RF) energy to the internally cooled electrodes for 12 minutes each for a total of 36 minutes. In the simultaneous monopolar and multipolar modes, RF energy was concurrently applied to the three perfused-cooled electrodes for 20 minutes at 150 watt with instillation of 6% hypertonic saline at 2 mL/min. During RFA, we measured the temperatures of the treated area at its center. The changes in impedance, the current and liver temperature during RFA, as well as the dimensions of the thermal ablation zones, were compared among the three groups. In the in vivo experiments, three coagulations were created by performing multipolar RFA in a pig via laparotomy with using same parameter as the ex vivo study. RESULTS In the ex vivo experiments, the impedance was gradually decreased during the RFA in groups B and C, but in group A, the impedance was increased during RFA and this induced activation by the pulsed RF technique. In groups A, B and C, the mean final-temperature values were 80+/-10 degrees C, 69+/-18 degrees C and 79+/-12 degrees C, respectively (p < 0.05). The multipolar mode created a larger volume of ablation than did the other modes: 37.6+/-4.0 cm3 (group A); 44.9+/-12.7 cm3 (group B); and 78.9+/-6.9 cm3 (group C) (p < 0.05). In the in vivo experiment, the pig well tolerated the RFA procedure and no major complications occurred during the 4 days of the follow-up period. The mean volume of coagulations produced by multipolar RFA in the pig liver was 60.5+/-17.9 cm3. CONCLUSION For the multiple probe RFA, the multipolar mode with hypertonic saline instillation was more efficient in generating larger areas of thermal ablation than either the consecutive or simultaneous monopolar modes.
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Affiliation(s)
- Jeong Min Lee
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Joon Koo Han
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Jae Young Lee
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Se Hyung Kim
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Jin Young Choi
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Min Woo Lee
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Seung Hong Choi
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Hong Eo
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
| | - Byung Ihn Choi
- Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine; Clinical Research Institute, Seoul National University Hospital, Seoul 110-744, Korea
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Lee JM, Han JK, Chang JM, Chung SY, Son KR, Kim SH, Lee JY, Choi BI. Radiofrequency Renal Ablation: In Vivo Comparison of Internally Cooled, Multitined Expandable and Internally Cooled Perfusion Electrodes. J Vasc Interv Radiol 2006; 17:549-56. [PMID: 16567680 DOI: 10.1097/01.rvi.0000202713.07943.fc] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To evaluate the in vivo efficiency of radiofrequency ablation using an internally cooled-perfusion (ICP) electrode for inducing coagulation necrosis compared with those of RFA using internally cooled or multitined expandable electrodes in porcine kidneys. MATERIALS AND METHODS Using a 200 W generator and internally cooled and ICP electrodes or a 150 W generator and a multitined expandable electrode, a total of 15 radiofrequency ablations were performed in the kidneys of nine pigs. After placement of an electrode in the lower pole of a kidney, one ablation zone was created using one of three different regimens: group A, radiofrequency ablation using an internally cooled electrode; group B, radiofrequency ablation using an ICP electrode with 14.6% NaCl solution instillation at 1 mL/minute; group C, radiofrequency ablation using a multitined expandable electrode. Three days after the procedures, contrast-enhanced CT scans were obtained to evaluate ablation region volumes, and kidneys were harvested for gross measurements. The three groups were compared with respect to technical parameters such as changes in impedance and current during radiofrequency ablation. The dimensions of thermal ablation zones created in the three groups were compared histologically. RESULTS In vivo study showed that ICP electrode allowed a greater energy delivery than internally cooled or multitined expandable electrode during radiofrequency ablation: 63.3 +/- 8.8 kJ in group A; 101 +/- 3.3 kJ in group B; and 61.8 +/- 12.5 kJ (P < .05). In vivo studies showed radiofrequency ablation using ICP electrode achieved larger mean coagulation volumes than radiofrequency ablation using the other electrodes: 12.0 +/- 3.9 cm(3) in group A; 30.5 +/- 7.6 cm(3) in group B; and 11.6 +/- 6.7 cm(3) in group C (P < .05). In addition, group B had a larger mean short-axis diameter of radiofrequency-induced coagulation necrosis than groups A or C: 2.6 +/- 0.5 cm in group A; 3.6 +/- 0.4 cm in group B; and 2.4 +/- 0.7 cm in group C (difference between groups B and C: P < .05). CONCLUSIONS Radiofrequency ablation using an ICP electrode showed better performance at creating coagulation necrosis than radiofrequency ablation using internally cooled or multitined expandable electrodes in this porcine renal model.
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Affiliation(s)
- Jeong Min Lee
- Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Chongno-gu, Korea
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